David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1 | #include <linux/kernel.h> |
| 2 | #include <linux/module.h> |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 3 | #include <linux/interrupt.h> |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 4 | #include <linux/irq.h> |
| 5 | #include <linux/spinlock.h> |
Alexandre Courbot | 1a989d0 | 2013-02-03 01:29:24 +0900 | [diff] [blame] | 6 | #include <linux/list.h> |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 7 | #include <linux/device.h> |
| 8 | #include <linux/err.h> |
| 9 | #include <linux/debugfs.h> |
| 10 | #include <linux/seq_file.h> |
| 11 | #include <linux/gpio.h> |
Anton Vorontsov | 391c970 | 2010-06-08 07:48:17 -0600 | [diff] [blame] | 12 | #include <linux/of_gpio.h> |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 13 | #include <linux/idr.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 14 | #include <linux/slab.h> |
Rafael J. Wysocki | 7b19981 | 2013-11-11 22:41:56 +0100 | [diff] [blame] | 15 | #include <linux/acpi.h> |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 16 | #include <linux/gpio/driver.h> |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 17 | |
Mika Westerberg | 664e3e5 | 2014-01-08 12:40:54 +0200 | [diff] [blame] | 18 | #include "gpiolib.h" |
| 19 | |
Uwe Kleine-König | 3f397c21 | 2011-05-20 00:40:19 -0600 | [diff] [blame] | 20 | #define CREATE_TRACE_POINTS |
| 21 | #include <trace/events/gpio.h> |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 22 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 23 | /* Implementation infrastructure for GPIO interfaces. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 24 | * |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 25 | * The GPIO programming interface allows for inlining speed-critical |
| 26 | * get/set operations for common cases, so that access to SOC-integrated |
| 27 | * GPIOs can sometimes cost only an instruction or two per bit. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 28 | */ |
| 29 | |
| 30 | |
| 31 | /* When debugging, extend minimal trust to callers and platform code. |
| 32 | * Also emit diagnostic messages that may help initial bringup, when |
| 33 | * board setup or driver bugs are most common. |
| 34 | * |
| 35 | * Otherwise, minimize overhead in what may be bitbanging codepaths. |
| 36 | */ |
| 37 | #ifdef DEBUG |
| 38 | #define extra_checks 1 |
| 39 | #else |
| 40 | #define extra_checks 0 |
| 41 | #endif |
| 42 | |
| 43 | /* gpio_lock prevents conflicts during gpio_desc[] table updates. |
| 44 | * While any GPIO is requested, its gpio_chip is not removable; |
| 45 | * each GPIO's "requested" flag serves as a lock and refcount. |
| 46 | */ |
| 47 | static DEFINE_SPINLOCK(gpio_lock); |
| 48 | |
| 49 | struct gpio_desc { |
| 50 | struct gpio_chip *chip; |
| 51 | unsigned long flags; |
| 52 | /* flag symbols are bit numbers */ |
| 53 | #define FLAG_REQUESTED 0 |
| 54 | #define FLAG_IS_OUT 1 |
Alexandre Courbot | 710b40e | 2013-02-02 23:44:06 +0900 | [diff] [blame] | 55 | #define FLAG_EXPORT 2 /* protected by sysfs_lock */ |
| 56 | #define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */ |
| 57 | #define FLAG_TRIG_FALL 4 /* trigger on falling edge */ |
| 58 | #define FLAG_TRIG_RISE 5 /* trigger on rising edge */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 59 | #define FLAG_ACTIVE_LOW 6 /* value has active low */ |
Alexandre Courbot | 710b40e | 2013-02-02 23:44:06 +0900 | [diff] [blame] | 60 | #define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */ |
| 61 | #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 62 | #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */ |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 63 | |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 64 | #define ID_SHIFT 16 /* add new flags before this one */ |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 65 | |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 66 | #define GPIO_FLAGS_MASK ((1 << ID_SHIFT) - 1) |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 67 | #define GPIO_TRIGGER_MASK (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE)) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 68 | |
| 69 | #ifdef CONFIG_DEBUG_FS |
| 70 | const char *label; |
| 71 | #endif |
| 72 | }; |
| 73 | static struct gpio_desc gpio_desc[ARCH_NR_GPIOS]; |
| 74 | |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 75 | #define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio) |
| 76 | |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 77 | static DEFINE_MUTEX(gpio_lookup_lock); |
| 78 | static LIST_HEAD(gpio_lookup_list); |
Alexandre Courbot | 1a989d0 | 2013-02-03 01:29:24 +0900 | [diff] [blame] | 79 | static LIST_HEAD(gpio_chips); |
| 80 | |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 81 | #ifdef CONFIG_GPIO_SYSFS |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 82 | static DEFINE_IDR(dirent_idr); |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 83 | #endif |
| 84 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 85 | static int gpiod_request(struct gpio_desc *desc, const char *label); |
| 86 | static void gpiod_free(struct gpio_desc *desc); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 87 | |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 88 | /* With descriptor prefix */ |
| 89 | |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 90 | #ifdef CONFIG_DEBUG_FS |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 91 | #define gpiod_emerg(desc, fmt, ...) \ |
| 92 | pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\ |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 93 | ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 94 | #define gpiod_crit(desc, fmt, ...) \ |
| 95 | pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 96 | ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 97 | #define gpiod_err(desc, fmt, ...) \ |
| 98 | pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 99 | ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 100 | #define gpiod_warn(desc, fmt, ...) \ |
| 101 | pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 102 | ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 103 | #define gpiod_info(desc, fmt, ...) \ |
| 104 | pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \ |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 105 | ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 106 | #define gpiod_dbg(desc, fmt, ...) \ |
| 107 | pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\ |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 108 | ##__VA_ARGS__) |
| 109 | #else |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 110 | #define gpiod_emerg(desc, fmt, ...) \ |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 111 | pr_emerg("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 112 | #define gpiod_crit(desc, fmt, ...) \ |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 113 | pr_crit("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 114 | #define gpiod_err(desc, fmt, ...) \ |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 115 | pr_err("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 116 | #define gpiod_warn(desc, fmt, ...) \ |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 117 | pr_warn("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 118 | #define gpiod_info(desc, fmt, ...) \ |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 119 | pr_info("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 120 | #define gpiod_dbg(desc, fmt, ...) \ |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 121 | pr_debug("gpio-%d: " fmt, desc_to_gpio(desc), ##__VA_ARGS__) |
Mark Brown | 7b17b59 | 2013-09-09 10:33:50 +0100 | [diff] [blame] | 122 | #endif |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 123 | |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 124 | /* With chip prefix */ |
| 125 | |
| 126 | #define chip_emerg(chip, fmt, ...) \ |
| 127 | pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) |
| 128 | #define chip_crit(chip, fmt, ...) \ |
| 129 | pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) |
| 130 | #define chip_err(chip, fmt, ...) \ |
| 131 | pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) |
| 132 | #define chip_warn(chip, fmt, ...) \ |
| 133 | pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) |
| 134 | #define chip_info(chip, fmt, ...) \ |
| 135 | pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) |
| 136 | #define chip_dbg(chip, fmt, ...) \ |
| 137 | pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__) |
| 138 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 139 | static inline void desc_set_label(struct gpio_desc *d, const char *label) |
| 140 | { |
| 141 | #ifdef CONFIG_DEBUG_FS |
| 142 | d->label = label; |
| 143 | #endif |
| 144 | } |
| 145 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 146 | /* |
| 147 | * Return the GPIO number of the passed descriptor relative to its chip |
| 148 | */ |
| 149 | static int gpio_chip_hwgpio(const struct gpio_desc *desc) |
| 150 | { |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 151 | return desc - &desc->chip->desc[0]; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 152 | } |
| 153 | |
| 154 | /** |
| 155 | * Convert a GPIO number to its descriptor |
| 156 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 157 | struct gpio_desc *gpio_to_desc(unsigned gpio) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 158 | { |
| 159 | if (WARN(!gpio_is_valid(gpio), "invalid GPIO %d\n", gpio)) |
| 160 | return NULL; |
| 161 | else |
| 162 | return &gpio_desc[gpio]; |
| 163 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 164 | EXPORT_SYMBOL_GPL(gpio_to_desc); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 165 | |
| 166 | /** |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 167 | * Convert an offset on a certain chip to a corresponding descriptor |
| 168 | */ |
| 169 | static struct gpio_desc *gpiochip_offset_to_desc(struct gpio_chip *chip, |
| 170 | unsigned int offset) |
| 171 | { |
Alexandre Courbot | b7d0a28 | 2013-12-03 12:31:11 +0900 | [diff] [blame] | 172 | if (offset >= chip->ngpio) |
| 173 | return ERR_PTR(-EINVAL); |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 174 | |
Alexandre Courbot | b7d0a28 | 2013-12-03 12:31:11 +0900 | [diff] [blame] | 175 | return &chip->desc[offset]; |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 176 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 177 | |
| 178 | /** |
| 179 | * Convert a GPIO descriptor to the integer namespace. |
| 180 | * This should disappear in the future but is needed since we still |
| 181 | * use GPIO numbers for error messages and sysfs nodes |
| 182 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 183 | int desc_to_gpio(const struct gpio_desc *desc) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 184 | { |
Alexandre Courbot | 8c0fca8 | 2013-10-04 10:59:57 -0700 | [diff] [blame] | 185 | return desc - &gpio_desc[0]; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 186 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 187 | EXPORT_SYMBOL_GPL(desc_to_gpio); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 188 | |
| 189 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 190 | /* Warn when drivers omit gpio_request() calls -- legal but ill-advised |
| 191 | * when setting direction, and otherwise illegal. Until board setup code |
| 192 | * and drivers use explicit requests everywhere (which won't happen when |
| 193 | * those calls have no teeth) we can't avoid autorequesting. This nag |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 194 | * message should motivate switching to explicit requests... so should |
| 195 | * the weaker cleanup after faults, compared to gpio_request(). |
David Brownell | 8a0cecf | 2009-04-02 16:57:06 -0700 | [diff] [blame] | 196 | * |
| 197 | * NOTE: the autorequest mechanism is going away; at this point it's |
| 198 | * only "legal" in the sense that (old) code using it won't break yet, |
| 199 | * but instead only triggers a WARN() stack dump. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 200 | */ |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 201 | static int gpio_ensure_requested(struct gpio_desc *desc) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 202 | { |
David Brownell | 8a0cecf | 2009-04-02 16:57:06 -0700 | [diff] [blame] | 203 | const struct gpio_chip *chip = desc->chip; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 204 | const int gpio = desc_to_gpio(desc); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 205 | |
David Brownell | 8a0cecf | 2009-04-02 16:57:06 -0700 | [diff] [blame] | 206 | if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0, |
| 207 | "autorequest GPIO-%d\n", gpio)) { |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 208 | if (!try_module_get(chip->owner)) { |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 209 | gpiod_err(desc, "%s: module can't be gotten\n", |
| 210 | __func__); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 211 | clear_bit(FLAG_REQUESTED, &desc->flags); |
| 212 | /* lose */ |
| 213 | return -EIO; |
| 214 | } |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 215 | desc_set_label(desc, "[auto]"); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 216 | /* caller must chip->request() w/o spinlock */ |
| 217 | if (chip->request) |
| 218 | return 1; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 219 | } |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 220 | return 0; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 221 | } |
| 222 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 223 | /** |
| 224 | * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs |
| 225 | * @desc: descriptor to return the chip of |
| 226 | */ |
| 227 | struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 228 | { |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 229 | return desc ? desc->chip : NULL; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 230 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 231 | EXPORT_SYMBOL_GPL(gpiod_to_chip); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 232 | |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 233 | /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
| 234 | static int gpiochip_find_base(int ngpio) |
| 235 | { |
Alexandre Courbot | 83cabe3 | 2013-02-03 01:29:28 +0900 | [diff] [blame] | 236 | struct gpio_chip *chip; |
| 237 | int base = ARCH_NR_GPIOS - ngpio; |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 238 | |
Alexandre Courbot | 83cabe3 | 2013-02-03 01:29:28 +0900 | [diff] [blame] | 239 | list_for_each_entry_reverse(chip, &gpio_chips, list) { |
| 240 | /* found a free space? */ |
| 241 | if (chip->base + chip->ngpio <= base) |
| 242 | break; |
| 243 | else |
| 244 | /* nope, check the space right before the chip */ |
| 245 | base = chip->base - ngpio; |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 246 | } |
| 247 | |
Alexandre Courbot | 83cabe3 | 2013-02-03 01:29:28 +0900 | [diff] [blame] | 248 | if (gpio_is_valid(base)) { |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 249 | pr_debug("%s: found new base at %d\n", __func__, base); |
Alexandre Courbot | 83cabe3 | 2013-02-03 01:29:28 +0900 | [diff] [blame] | 250 | return base; |
| 251 | } else { |
| 252 | pr_err("%s: cannot find free range\n", __func__); |
| 253 | return -ENOSPC; |
Anton Vorontsov | 169b6a7 | 2008-04-28 02:14:47 -0700 | [diff] [blame] | 254 | } |
Anton Vorontsov | 169b6a7 | 2008-04-28 02:14:47 -0700 | [diff] [blame] | 255 | } |
| 256 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 257 | /** |
| 258 | * gpiod_get_direction - return the current direction of a GPIO |
| 259 | * @desc: GPIO to get the direction of |
| 260 | * |
| 261 | * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. |
| 262 | * |
| 263 | * This function may sleep if gpiod_cansleep() is true. |
| 264 | */ |
| 265 | int gpiod_get_direction(const struct gpio_desc *desc) |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 266 | { |
| 267 | struct gpio_chip *chip; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 268 | unsigned offset; |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 269 | int status = -EINVAL; |
| 270 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 271 | chip = gpiod_to_chip(desc); |
| 272 | offset = gpio_chip_hwgpio(desc); |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 273 | |
| 274 | if (!chip->get_direction) |
| 275 | return status; |
| 276 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 277 | status = chip->get_direction(chip, offset); |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 278 | if (status > 0) { |
| 279 | /* GPIOF_DIR_IN, or other positive */ |
| 280 | status = 1; |
Alexandre Courbot | def6343 | 2013-02-15 14:46:15 +0900 | [diff] [blame] | 281 | /* FLAG_IS_OUT is just a cache of the result of get_direction(), |
| 282 | * so it does not affect constness per se */ |
| 283 | clear_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 284 | } |
| 285 | if (status == 0) { |
| 286 | /* GPIOF_DIR_OUT */ |
Alexandre Courbot | def6343 | 2013-02-15 14:46:15 +0900 | [diff] [blame] | 287 | set_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 288 | } |
| 289 | return status; |
| 290 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 291 | EXPORT_SYMBOL_GPL(gpiod_get_direction); |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 292 | |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 293 | #ifdef CONFIG_GPIO_SYSFS |
| 294 | |
| 295 | /* lock protects against unexport_gpio() being called while |
| 296 | * sysfs files are active. |
| 297 | */ |
| 298 | static DEFINE_MUTEX(sysfs_lock); |
| 299 | |
| 300 | /* |
| 301 | * /sys/class/gpio/gpioN... only for GPIOs that are exported |
| 302 | * /direction |
| 303 | * * MAY BE OMITTED if kernel won't allow direction changes |
| 304 | * * is read/write as "in" or "out" |
| 305 | * * may also be written as "high" or "low", initializing |
| 306 | * output value as specified ("out" implies "low") |
| 307 | * /value |
| 308 | * * always readable, subject to hardware behavior |
| 309 | * * may be writable, as zero/nonzero |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 310 | * /edge |
| 311 | * * configures behavior of poll(2) on /value |
| 312 | * * available only if pin can generate IRQs on input |
| 313 | * * is read/write as "none", "falling", "rising", or "both" |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 314 | * /active_low |
| 315 | * * configures polarity of /value |
| 316 | * * is read/write as zero/nonzero |
| 317 | * * also affects existing and subsequent "falling" and "rising" |
| 318 | * /edge configuration |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 319 | */ |
| 320 | |
| 321 | static ssize_t gpio_direction_show(struct device *dev, |
| 322 | struct device_attribute *attr, char *buf) |
| 323 | { |
Alexandre Courbot | def6343 | 2013-02-15 14:46:15 +0900 | [diff] [blame] | 324 | const struct gpio_desc *desc = dev_get_drvdata(dev); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 325 | ssize_t status; |
| 326 | |
| 327 | mutex_lock(&sysfs_lock); |
| 328 | |
Alexandre Courbot | 476171ce | 2013-02-04 17:42:04 +0900 | [diff] [blame] | 329 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 330 | status = -EIO; |
Alexandre Courbot | 476171ce | 2013-02-04 17:42:04 +0900 | [diff] [blame] | 331 | } else { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 332 | gpiod_get_direction(desc); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 333 | status = sprintf(buf, "%s\n", |
| 334 | test_bit(FLAG_IS_OUT, &desc->flags) |
| 335 | ? "out" : "in"); |
Alexandre Courbot | 476171ce | 2013-02-04 17:42:04 +0900 | [diff] [blame] | 336 | } |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 337 | |
| 338 | mutex_unlock(&sysfs_lock); |
| 339 | return status; |
| 340 | } |
| 341 | |
| 342 | static ssize_t gpio_direction_store(struct device *dev, |
| 343 | struct device_attribute *attr, const char *buf, size_t size) |
| 344 | { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 345 | struct gpio_desc *desc = dev_get_drvdata(dev); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 346 | ssize_t status; |
| 347 | |
| 348 | mutex_lock(&sysfs_lock); |
| 349 | |
| 350 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
| 351 | status = -EIO; |
| 352 | else if (sysfs_streq(buf, "high")) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 353 | status = gpiod_direction_output(desc, 1); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 354 | else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low")) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 355 | status = gpiod_direction_output(desc, 0); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 356 | else if (sysfs_streq(buf, "in")) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 357 | status = gpiod_direction_input(desc); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 358 | else |
| 359 | status = -EINVAL; |
| 360 | |
| 361 | mutex_unlock(&sysfs_lock); |
| 362 | return status ? : size; |
| 363 | } |
| 364 | |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 365 | static /* const */ DEVICE_ATTR(direction, 0644, |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 366 | gpio_direction_show, gpio_direction_store); |
| 367 | |
| 368 | static ssize_t gpio_value_show(struct device *dev, |
| 369 | struct device_attribute *attr, char *buf) |
| 370 | { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 371 | struct gpio_desc *desc = dev_get_drvdata(dev); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 372 | ssize_t status; |
| 373 | |
| 374 | mutex_lock(&sysfs_lock); |
| 375 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 376 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 377 | status = -EIO; |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 378 | else |
| 379 | status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc)); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 380 | |
| 381 | mutex_unlock(&sysfs_lock); |
| 382 | return status; |
| 383 | } |
| 384 | |
| 385 | static ssize_t gpio_value_store(struct device *dev, |
| 386 | struct device_attribute *attr, const char *buf, size_t size) |
| 387 | { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 388 | struct gpio_desc *desc = dev_get_drvdata(dev); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 389 | ssize_t status; |
| 390 | |
| 391 | mutex_lock(&sysfs_lock); |
| 392 | |
| 393 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
| 394 | status = -EIO; |
| 395 | else if (!test_bit(FLAG_IS_OUT, &desc->flags)) |
| 396 | status = -EPERM; |
| 397 | else { |
| 398 | long value; |
| 399 | |
Jingoo Han | a3d88c9 | 2013-07-19 16:12:50 +0900 | [diff] [blame] | 400 | status = kstrtol(buf, 0, &value); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 401 | if (status == 0) { |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 402 | gpiod_set_value_cansleep(desc, value); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 403 | status = size; |
| 404 | } |
| 405 | } |
| 406 | |
| 407 | mutex_unlock(&sysfs_lock); |
| 408 | return status; |
| 409 | } |
| 410 | |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 411 | static const DEVICE_ATTR(value, 0644, |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 412 | gpio_value_show, gpio_value_store); |
| 413 | |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 414 | static irqreturn_t gpio_sysfs_irq(int irq, void *priv) |
| 415 | { |
Tejun Heo | 324a56e | 2013-12-11 14:11:53 -0500 | [diff] [blame] | 416 | struct kernfs_node *value_sd = priv; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 417 | |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 418 | sysfs_notify_dirent(value_sd); |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 419 | return IRQ_HANDLED; |
| 420 | } |
| 421 | |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 422 | static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev, |
| 423 | unsigned long gpio_flags) |
| 424 | { |
Tejun Heo | 324a56e | 2013-12-11 14:11:53 -0500 | [diff] [blame] | 425 | struct kernfs_node *value_sd; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 426 | unsigned long irq_flags; |
| 427 | int ret, irq, id; |
| 428 | |
| 429 | if ((desc->flags & GPIO_TRIGGER_MASK) == gpio_flags) |
| 430 | return 0; |
| 431 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 432 | irq = gpiod_to_irq(desc); |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 433 | if (irq < 0) |
| 434 | return -EIO; |
| 435 | |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 436 | id = desc->flags >> ID_SHIFT; |
| 437 | value_sd = idr_find(&dirent_idr, id); |
| 438 | if (value_sd) |
| 439 | free_irq(irq, value_sd); |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 440 | |
| 441 | desc->flags &= ~GPIO_TRIGGER_MASK; |
| 442 | |
| 443 | if (!gpio_flags) { |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 444 | gpiod_unlock_as_irq(desc); |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 445 | ret = 0; |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 446 | goto free_id; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 447 | } |
| 448 | |
| 449 | irq_flags = IRQF_SHARED; |
| 450 | if (test_bit(FLAG_TRIG_FALL, &gpio_flags)) |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 451 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
| 452 | IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 453 | if (test_bit(FLAG_TRIG_RISE, &gpio_flags)) |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 454 | irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? |
| 455 | IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 456 | |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 457 | if (!value_sd) { |
Tejun Heo | 388975c | 2013-09-11 23:19:13 -0400 | [diff] [blame] | 458 | value_sd = sysfs_get_dirent(dev->kobj.sd, "value"); |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 459 | if (!value_sd) { |
| 460 | ret = -ENODEV; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 461 | goto err_out; |
| 462 | } |
| 463 | |
Tejun Heo | 62f516b | 2013-02-27 17:04:06 -0800 | [diff] [blame] | 464 | ret = idr_alloc(&dirent_idr, value_sd, 1, 0, GFP_KERNEL); |
| 465 | if (ret < 0) |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 466 | goto free_sd; |
Tejun Heo | 62f516b | 2013-02-27 17:04:06 -0800 | [diff] [blame] | 467 | id = ret; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 468 | |
| 469 | desc->flags &= GPIO_FLAGS_MASK; |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 470 | desc->flags |= (unsigned long)id << ID_SHIFT; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 471 | |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 472 | if (desc->flags >> ID_SHIFT != id) { |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 473 | ret = -ERANGE; |
| 474 | goto free_id; |
| 475 | } |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 476 | } |
| 477 | |
Daniel Gl?ckner | 364fadb3 | 2010-08-10 18:02:26 -0700 | [diff] [blame] | 478 | ret = request_any_context_irq(irq, gpio_sysfs_irq, irq_flags, |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 479 | "gpiolib", value_sd); |
Daniel Gl?ckner | 364fadb3 | 2010-08-10 18:02:26 -0700 | [diff] [blame] | 480 | if (ret < 0) |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 481 | goto free_id; |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 482 | |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 483 | ret = gpiod_lock_as_irq(desc); |
| 484 | if (ret < 0) { |
| 485 | gpiod_warn(desc, "failed to flag the GPIO for IRQ\n"); |
| 486 | goto free_id; |
| 487 | } |
| 488 | |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 489 | desc->flags |= gpio_flags; |
| 490 | return 0; |
| 491 | |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 492 | free_id: |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 493 | idr_remove(&dirent_idr, id); |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 494 | desc->flags &= GPIO_FLAGS_MASK; |
Daniel Gl?ckner | 5ba1821 | 2010-08-10 18:02:25 -0700 | [diff] [blame] | 495 | free_sd: |
| 496 | if (value_sd) |
| 497 | sysfs_put(value_sd); |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 498 | err_out: |
| 499 | return ret; |
| 500 | } |
| 501 | |
| 502 | static const struct { |
| 503 | const char *name; |
| 504 | unsigned long flags; |
| 505 | } trigger_types[] = { |
| 506 | { "none", 0 }, |
| 507 | { "falling", BIT(FLAG_TRIG_FALL) }, |
| 508 | { "rising", BIT(FLAG_TRIG_RISE) }, |
| 509 | { "both", BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE) }, |
| 510 | }; |
| 511 | |
| 512 | static ssize_t gpio_edge_show(struct device *dev, |
| 513 | struct device_attribute *attr, char *buf) |
| 514 | { |
| 515 | const struct gpio_desc *desc = dev_get_drvdata(dev); |
| 516 | ssize_t status; |
| 517 | |
| 518 | mutex_lock(&sysfs_lock); |
| 519 | |
| 520 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
| 521 | status = -EIO; |
| 522 | else { |
| 523 | int i; |
| 524 | |
| 525 | status = 0; |
| 526 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) |
| 527 | if ((desc->flags & GPIO_TRIGGER_MASK) |
| 528 | == trigger_types[i].flags) { |
| 529 | status = sprintf(buf, "%s\n", |
| 530 | trigger_types[i].name); |
| 531 | break; |
| 532 | } |
| 533 | } |
| 534 | |
| 535 | mutex_unlock(&sysfs_lock); |
| 536 | return status; |
| 537 | } |
| 538 | |
| 539 | static ssize_t gpio_edge_store(struct device *dev, |
| 540 | struct device_attribute *attr, const char *buf, size_t size) |
| 541 | { |
| 542 | struct gpio_desc *desc = dev_get_drvdata(dev); |
| 543 | ssize_t status; |
| 544 | int i; |
| 545 | |
| 546 | for (i = 0; i < ARRAY_SIZE(trigger_types); i++) |
| 547 | if (sysfs_streq(trigger_types[i].name, buf)) |
| 548 | goto found; |
| 549 | return -EINVAL; |
| 550 | |
| 551 | found: |
| 552 | mutex_lock(&sysfs_lock); |
| 553 | |
| 554 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
| 555 | status = -EIO; |
| 556 | else { |
| 557 | status = gpio_setup_irq(desc, dev, trigger_types[i].flags); |
| 558 | if (!status) |
| 559 | status = size; |
| 560 | } |
| 561 | |
| 562 | mutex_unlock(&sysfs_lock); |
| 563 | |
| 564 | return status; |
| 565 | } |
| 566 | |
| 567 | static DEVICE_ATTR(edge, 0644, gpio_edge_show, gpio_edge_store); |
| 568 | |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 569 | static int sysfs_set_active_low(struct gpio_desc *desc, struct device *dev, |
| 570 | int value) |
| 571 | { |
| 572 | int status = 0; |
| 573 | |
| 574 | if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value) |
| 575 | return 0; |
| 576 | |
| 577 | if (value) |
| 578 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| 579 | else |
| 580 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| 581 | |
| 582 | /* reconfigure poll(2) support if enabled on one edge only */ |
| 583 | if (dev != NULL && (!!test_bit(FLAG_TRIG_RISE, &desc->flags) ^ |
| 584 | !!test_bit(FLAG_TRIG_FALL, &desc->flags))) { |
| 585 | unsigned long trigger_flags = desc->flags & GPIO_TRIGGER_MASK; |
| 586 | |
| 587 | gpio_setup_irq(desc, dev, 0); |
| 588 | status = gpio_setup_irq(desc, dev, trigger_flags); |
| 589 | } |
| 590 | |
| 591 | return status; |
| 592 | } |
| 593 | |
| 594 | static ssize_t gpio_active_low_show(struct device *dev, |
| 595 | struct device_attribute *attr, char *buf) |
| 596 | { |
| 597 | const struct gpio_desc *desc = dev_get_drvdata(dev); |
| 598 | ssize_t status; |
| 599 | |
| 600 | mutex_lock(&sysfs_lock); |
| 601 | |
| 602 | if (!test_bit(FLAG_EXPORT, &desc->flags)) |
| 603 | status = -EIO; |
| 604 | else |
| 605 | status = sprintf(buf, "%d\n", |
| 606 | !!test_bit(FLAG_ACTIVE_LOW, &desc->flags)); |
| 607 | |
| 608 | mutex_unlock(&sysfs_lock); |
| 609 | |
| 610 | return status; |
| 611 | } |
| 612 | |
| 613 | static ssize_t gpio_active_low_store(struct device *dev, |
| 614 | struct device_attribute *attr, const char *buf, size_t size) |
| 615 | { |
| 616 | struct gpio_desc *desc = dev_get_drvdata(dev); |
| 617 | ssize_t status; |
| 618 | |
| 619 | mutex_lock(&sysfs_lock); |
| 620 | |
| 621 | if (!test_bit(FLAG_EXPORT, &desc->flags)) { |
| 622 | status = -EIO; |
| 623 | } else { |
| 624 | long value; |
| 625 | |
Jingoo Han | a3d88c9 | 2013-07-19 16:12:50 +0900 | [diff] [blame] | 626 | status = kstrtol(buf, 0, &value); |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 627 | if (status == 0) |
| 628 | status = sysfs_set_active_low(desc, dev, value != 0); |
| 629 | } |
| 630 | |
| 631 | mutex_unlock(&sysfs_lock); |
| 632 | |
| 633 | return status ? : size; |
| 634 | } |
| 635 | |
| 636 | static const DEVICE_ATTR(active_low, 0644, |
| 637 | gpio_active_low_show, gpio_active_low_store); |
| 638 | |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 639 | static const struct attribute *gpio_attrs[] = { |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 640 | &dev_attr_value.attr, |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 641 | &dev_attr_active_low.attr, |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 642 | NULL, |
| 643 | }; |
| 644 | |
| 645 | static const struct attribute_group gpio_attr_group = { |
| 646 | .attrs = (struct attribute **) gpio_attrs, |
| 647 | }; |
| 648 | |
| 649 | /* |
| 650 | * /sys/class/gpio/gpiochipN/ |
| 651 | * /base ... matching gpio_chip.base (N) |
| 652 | * /label ... matching gpio_chip.label |
| 653 | * /ngpio ... matching gpio_chip.ngpio |
| 654 | */ |
| 655 | |
| 656 | static ssize_t chip_base_show(struct device *dev, |
| 657 | struct device_attribute *attr, char *buf) |
| 658 | { |
| 659 | const struct gpio_chip *chip = dev_get_drvdata(dev); |
| 660 | |
| 661 | return sprintf(buf, "%d\n", chip->base); |
| 662 | } |
| 663 | static DEVICE_ATTR(base, 0444, chip_base_show, NULL); |
| 664 | |
| 665 | static ssize_t chip_label_show(struct device *dev, |
| 666 | struct device_attribute *attr, char *buf) |
| 667 | { |
| 668 | const struct gpio_chip *chip = dev_get_drvdata(dev); |
| 669 | |
| 670 | return sprintf(buf, "%s\n", chip->label ? : ""); |
| 671 | } |
| 672 | static DEVICE_ATTR(label, 0444, chip_label_show, NULL); |
| 673 | |
| 674 | static ssize_t chip_ngpio_show(struct device *dev, |
| 675 | struct device_attribute *attr, char *buf) |
| 676 | { |
| 677 | const struct gpio_chip *chip = dev_get_drvdata(dev); |
| 678 | |
| 679 | return sprintf(buf, "%u\n", chip->ngpio); |
| 680 | } |
| 681 | static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL); |
| 682 | |
| 683 | static const struct attribute *gpiochip_attrs[] = { |
| 684 | &dev_attr_base.attr, |
| 685 | &dev_attr_label.attr, |
| 686 | &dev_attr_ngpio.attr, |
| 687 | NULL, |
| 688 | }; |
| 689 | |
| 690 | static const struct attribute_group gpiochip_attr_group = { |
| 691 | .attrs = (struct attribute **) gpiochip_attrs, |
| 692 | }; |
| 693 | |
| 694 | /* |
| 695 | * /sys/class/gpio/export ... write-only |
| 696 | * integer N ... number of GPIO to export (full access) |
| 697 | * /sys/class/gpio/unexport ... write-only |
| 698 | * integer N ... number of GPIO to unexport |
| 699 | */ |
Andi Kleen | 28812fe | 2010-01-05 12:48:07 +0100 | [diff] [blame] | 700 | static ssize_t export_store(struct class *class, |
| 701 | struct class_attribute *attr, |
| 702 | const char *buf, size_t len) |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 703 | { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 704 | long gpio; |
| 705 | struct gpio_desc *desc; |
| 706 | int status; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 707 | |
Jingoo Han | a3d88c9 | 2013-07-19 16:12:50 +0900 | [diff] [blame] | 708 | status = kstrtol(buf, 0, &gpio); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 709 | if (status < 0) |
| 710 | goto done; |
| 711 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 712 | desc = gpio_to_desc(gpio); |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 713 | /* reject invalid GPIOs */ |
| 714 | if (!desc) { |
| 715 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); |
| 716 | return -EINVAL; |
| 717 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 718 | |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 719 | /* No extra locking here; FLAG_SYSFS just signifies that the |
| 720 | * request and export were done by on behalf of userspace, so |
| 721 | * they may be undone on its behalf too. |
| 722 | */ |
| 723 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 724 | status = gpiod_request(desc, "sysfs"); |
Mathias Nyman | ad2fab3 | 2012-10-25 14:03:03 +0300 | [diff] [blame] | 725 | if (status < 0) { |
| 726 | if (status == -EPROBE_DEFER) |
| 727 | status = -ENODEV; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 728 | goto done; |
Mathias Nyman | ad2fab3 | 2012-10-25 14:03:03 +0300 | [diff] [blame] | 729 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 730 | status = gpiod_export(desc, true); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 731 | if (status < 0) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 732 | gpiod_free(desc); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 733 | else |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 734 | set_bit(FLAG_SYSFS, &desc->flags); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 735 | |
| 736 | done: |
| 737 | if (status) |
| 738 | pr_debug("%s: status %d\n", __func__, status); |
| 739 | return status ? : len; |
| 740 | } |
| 741 | |
Andi Kleen | 28812fe | 2010-01-05 12:48:07 +0100 | [diff] [blame] | 742 | static ssize_t unexport_store(struct class *class, |
| 743 | struct class_attribute *attr, |
| 744 | const char *buf, size_t len) |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 745 | { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 746 | long gpio; |
| 747 | struct gpio_desc *desc; |
| 748 | int status; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 749 | |
Jingoo Han | a3d88c9 | 2013-07-19 16:12:50 +0900 | [diff] [blame] | 750 | status = kstrtol(buf, 0, &gpio); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 751 | if (status < 0) |
| 752 | goto done; |
| 753 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 754 | desc = gpio_to_desc(gpio); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 755 | /* reject bogus commands (gpio_unexport ignores them) */ |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 756 | if (!desc) { |
| 757 | pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); |
| 758 | return -EINVAL; |
| 759 | } |
| 760 | |
| 761 | status = -EINVAL; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 762 | |
| 763 | /* No extra locking here; FLAG_SYSFS just signifies that the |
| 764 | * request and export were done by on behalf of userspace, so |
| 765 | * they may be undone on its behalf too. |
| 766 | */ |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 767 | if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) { |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 768 | status = 0; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 769 | gpiod_free(desc); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 770 | } |
| 771 | done: |
| 772 | if (status) |
| 773 | pr_debug("%s: status %d\n", __func__, status); |
| 774 | return status ? : len; |
| 775 | } |
| 776 | |
| 777 | static struct class_attribute gpio_class_attrs[] = { |
| 778 | __ATTR(export, 0200, NULL, export_store), |
| 779 | __ATTR(unexport, 0200, NULL, unexport_store), |
| 780 | __ATTR_NULL, |
| 781 | }; |
| 782 | |
| 783 | static struct class gpio_class = { |
| 784 | .name = "gpio", |
| 785 | .owner = THIS_MODULE, |
| 786 | |
| 787 | .class_attrs = gpio_class_attrs, |
| 788 | }; |
| 789 | |
| 790 | |
| 791 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 792 | * gpiod_export - export a GPIO through sysfs |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 793 | * @gpio: gpio to make available, already requested |
| 794 | * @direction_may_change: true if userspace may change gpio direction |
| 795 | * Context: arch_initcall or later |
| 796 | * |
| 797 | * When drivers want to make a GPIO accessible to userspace after they |
| 798 | * have requested it -- perhaps while debugging, or as part of their |
| 799 | * public interface -- they may use this routine. If the GPIO can |
| 800 | * change direction (some can't) and the caller allows it, userspace |
| 801 | * will see "direction" sysfs attribute which may be used to change |
| 802 | * the gpio's direction. A "value" attribute will always be provided. |
| 803 | * |
| 804 | * Returns zero on success, else an error. |
| 805 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 806 | int gpiod_export(struct gpio_desc *desc, bool direction_may_change) |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 807 | { |
| 808 | unsigned long flags; |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 809 | int status; |
Uwe Kleine-König | 6215499 | 2010-05-26 14:42:17 -0700 | [diff] [blame] | 810 | const char *ioname = NULL; |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 811 | struct device *dev; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 812 | int offset; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 813 | |
| 814 | /* can't export until sysfs is available ... */ |
| 815 | if (!gpio_class.p) { |
| 816 | pr_debug("%s: called too early!\n", __func__); |
| 817 | return -ENOENT; |
| 818 | } |
| 819 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 820 | if (!desc) { |
| 821 | pr_debug("%s: invalid gpio descriptor\n", __func__); |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 822 | return -EINVAL; |
| 823 | } |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 824 | |
| 825 | mutex_lock(&sysfs_lock); |
| 826 | |
| 827 | spin_lock_irqsave(&gpio_lock, flags); |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 828 | if (!test_bit(FLAG_REQUESTED, &desc->flags) || |
| 829 | test_bit(FLAG_EXPORT, &desc->flags)) { |
| 830 | spin_unlock_irqrestore(&gpio_lock, flags); |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 831 | gpiod_dbg(desc, "%s: unavailable (requested=%d, exported=%d)\n", |
| 832 | __func__, |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 833 | test_bit(FLAG_REQUESTED, &desc->flags), |
| 834 | test_bit(FLAG_EXPORT, &desc->flags)); |
Dan Carpenter | 529f2ad | 2012-10-26 09:59:43 +0300 | [diff] [blame] | 835 | status = -EPERM; |
| 836 | goto fail_unlock; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 837 | } |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 838 | |
| 839 | if (!desc->chip->direction_input || !desc->chip->direction_output) |
| 840 | direction_may_change = false; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 841 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 842 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 843 | offset = gpio_chip_hwgpio(desc); |
| 844 | if (desc->chip->names && desc->chip->names[offset]) |
| 845 | ioname = desc->chip->names[offset]; |
Daniel Silverstone | 926b663 | 2009-04-02 16:57:05 -0700 | [diff] [blame] | 846 | |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 847 | dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0), |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 848 | desc, ioname ? ioname : "gpio%u", |
| 849 | desc_to_gpio(desc)); |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 850 | if (IS_ERR(dev)) { |
| 851 | status = PTR_ERR(dev); |
| 852 | goto fail_unlock; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 853 | } |
| 854 | |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 855 | status = sysfs_create_group(&dev->kobj, &gpio_attr_group); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 856 | if (status) |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 857 | goto fail_unregister_device; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 858 | |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 859 | if (direction_may_change) { |
| 860 | status = device_create_file(dev, &dev_attr_direction); |
| 861 | if (status) |
| 862 | goto fail_unregister_device; |
| 863 | } |
| 864 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 865 | if (gpiod_to_irq(desc) >= 0 && (direction_may_change || |
Ryan Mallon | fc4e251 | 2012-10-22 11:39:12 +1100 | [diff] [blame] | 866 | !test_bit(FLAG_IS_OUT, &desc->flags))) { |
| 867 | status = device_create_file(dev, &dev_attr_edge); |
| 868 | if (status) |
| 869 | goto fail_unregister_device; |
| 870 | } |
| 871 | |
| 872 | set_bit(FLAG_EXPORT, &desc->flags); |
| 873 | mutex_unlock(&sysfs_lock); |
| 874 | return 0; |
| 875 | |
| 876 | fail_unregister_device: |
| 877 | device_unregister(dev); |
| 878 | fail_unlock: |
| 879 | mutex_unlock(&sysfs_lock); |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 880 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 881 | return status; |
| 882 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 883 | EXPORT_SYMBOL_GPL(gpiod_export); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 884 | |
Michał Mirosław | 9f3b795 | 2013-02-01 20:40:17 +0100 | [diff] [blame] | 885 | static int match_export(struct device *dev, const void *data) |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 886 | { |
| 887 | return dev_get_drvdata(dev) == data; |
| 888 | } |
| 889 | |
| 890 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 891 | * gpiod_export_link - create a sysfs link to an exported GPIO node |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 892 | * @dev: device under which to create symlink |
| 893 | * @name: name of the symlink |
| 894 | * @gpio: gpio to create symlink to, already exported |
| 895 | * |
| 896 | * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN |
| 897 | * node. Caller is responsible for unlinking. |
| 898 | * |
| 899 | * Returns zero on success, else an error. |
| 900 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 901 | int gpiod_export_link(struct device *dev, const char *name, |
| 902 | struct gpio_desc *desc) |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 903 | { |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 904 | int status = -EINVAL; |
| 905 | |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 906 | if (!desc) { |
| 907 | pr_warn("%s: invalid GPIO\n", __func__); |
| 908 | return -EINVAL; |
| 909 | } |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 910 | |
| 911 | mutex_lock(&sysfs_lock); |
| 912 | |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 913 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
| 914 | struct device *tdev; |
| 915 | |
| 916 | tdev = class_find_device(&gpio_class, NULL, desc, match_export); |
| 917 | if (tdev != NULL) { |
| 918 | status = sysfs_create_link(&dev->kobj, &tdev->kobj, |
| 919 | name); |
| 920 | } else { |
| 921 | status = -ENODEV; |
| 922 | } |
| 923 | } |
| 924 | |
| 925 | mutex_unlock(&sysfs_lock); |
| 926 | |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 927 | if (status) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 928 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 929 | |
| 930 | return status; |
| 931 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 932 | EXPORT_SYMBOL_GPL(gpiod_export_link); |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 933 | |
| 934 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 935 | * gpiod_sysfs_set_active_low - set the polarity of gpio sysfs value |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 936 | * @gpio: gpio to change |
| 937 | * @value: non-zero to use active low, i.e. inverted values |
| 938 | * |
| 939 | * Set the polarity of /sys/class/gpio/gpioN/value sysfs attribute. |
| 940 | * The GPIO does not have to be exported yet. If poll(2) support has |
| 941 | * been enabled for either rising or falling edge, it will be |
| 942 | * reconfigured to follow the new polarity. |
| 943 | * |
| 944 | * Returns zero on success, else an error. |
| 945 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 946 | int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value) |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 947 | { |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 948 | struct device *dev = NULL; |
| 949 | int status = -EINVAL; |
| 950 | |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 951 | if (!desc) { |
| 952 | pr_warn("%s: invalid GPIO\n", __func__); |
| 953 | return -EINVAL; |
| 954 | } |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 955 | |
| 956 | mutex_lock(&sysfs_lock); |
| 957 | |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 958 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 959 | dev = class_find_device(&gpio_class, NULL, desc, match_export); |
| 960 | if (dev == NULL) { |
| 961 | status = -ENODEV; |
| 962 | goto unlock; |
| 963 | } |
| 964 | } |
| 965 | |
| 966 | status = sysfs_set_active_low(desc, dev, value); |
| 967 | |
| 968 | unlock: |
| 969 | mutex_unlock(&sysfs_lock); |
| 970 | |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 971 | if (status) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 972 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 973 | |
| 974 | return status; |
| 975 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 976 | EXPORT_SYMBOL_GPL(gpiod_sysfs_set_active_low); |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 977 | |
Jani Nikula | a4177ee | 2009-09-22 16:46:33 -0700 | [diff] [blame] | 978 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 979 | * gpiod_unexport - reverse effect of gpio_export() |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 980 | * @gpio: gpio to make unavailable |
| 981 | * |
| 982 | * This is implicit on gpio_free(). |
| 983 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 984 | void gpiod_unexport(struct gpio_desc *desc) |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 985 | { |
Jon Povey | 6a99ad4 | 2010-07-27 13:18:06 -0700 | [diff] [blame] | 986 | int status = 0; |
Ming Lei | 864533c | 2012-02-13 22:53:20 +0800 | [diff] [blame] | 987 | struct device *dev = NULL; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 988 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 989 | if (!desc) { |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 990 | pr_warn("%s: invalid GPIO\n", __func__); |
| 991 | return; |
Jon Povey | 6a99ad4 | 2010-07-27 13:18:06 -0700 | [diff] [blame] | 992 | } |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 993 | |
| 994 | mutex_lock(&sysfs_lock); |
| 995 | |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 996 | if (test_bit(FLAG_EXPORT, &desc->flags)) { |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 997 | |
| 998 | dev = class_find_device(&gpio_class, NULL, desc, match_export); |
| 999 | if (dev) { |
Daniel Glöckner | ff77c35 | 2009-09-22 16:46:38 -0700 | [diff] [blame] | 1000 | gpio_setup_irq(desc, dev, 0); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1001 | clear_bit(FLAG_EXPORT, &desc->flags); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1002 | } else |
| 1003 | status = -ENODEV; |
| 1004 | } |
| 1005 | |
| 1006 | mutex_unlock(&sysfs_lock); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1007 | |
Ming Lei | 864533c | 2012-02-13 22:53:20 +0800 | [diff] [blame] | 1008 | if (dev) { |
| 1009 | device_unregister(dev); |
| 1010 | put_device(dev); |
| 1011 | } |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1012 | |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1013 | if (status) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1014 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1015 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1016 | EXPORT_SYMBOL_GPL(gpiod_unexport); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1017 | |
| 1018 | static int gpiochip_export(struct gpio_chip *chip) |
| 1019 | { |
| 1020 | int status; |
| 1021 | struct device *dev; |
| 1022 | |
| 1023 | /* Many systems register gpio chips for SOC support very early, |
| 1024 | * before driver model support is available. In those cases we |
| 1025 | * export this later, in gpiolib_sysfs_init() ... here we just |
| 1026 | * verify that _some_ field of gpio_class got initialized. |
| 1027 | */ |
| 1028 | if (!gpio_class.p) |
| 1029 | return 0; |
| 1030 | |
| 1031 | /* use chip->base for the ID; it's already known to be unique */ |
| 1032 | mutex_lock(&sysfs_lock); |
| 1033 | dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip, |
| 1034 | "gpiochip%d", chip->base); |
Sergei Shtylyov | d62668e | 2009-11-11 14:26:50 -0800 | [diff] [blame] | 1035 | if (!IS_ERR(dev)) { |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1036 | status = sysfs_create_group(&dev->kobj, |
| 1037 | &gpiochip_attr_group); |
| 1038 | } else |
Sergei Shtylyov | d62668e | 2009-11-11 14:26:50 -0800 | [diff] [blame] | 1039 | status = PTR_ERR(dev); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1040 | chip->exported = (status == 0); |
| 1041 | mutex_unlock(&sysfs_lock); |
| 1042 | |
| 1043 | if (status) { |
| 1044 | unsigned long flags; |
| 1045 | unsigned gpio; |
| 1046 | |
| 1047 | spin_lock_irqsave(&gpio_lock, flags); |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1048 | gpio = 0; |
| 1049 | while (gpio < chip->ngpio) |
| 1050 | chip->desc[gpio++].chip = NULL; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1051 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1052 | |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 1053 | chip_dbg(chip, "%s: status %d\n", __func__, status); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1054 | } |
| 1055 | |
| 1056 | return status; |
| 1057 | } |
| 1058 | |
| 1059 | static void gpiochip_unexport(struct gpio_chip *chip) |
| 1060 | { |
| 1061 | int status; |
| 1062 | struct device *dev; |
| 1063 | |
| 1064 | mutex_lock(&sysfs_lock); |
| 1065 | dev = class_find_device(&gpio_class, NULL, chip, match_export); |
| 1066 | if (dev) { |
| 1067 | put_device(dev); |
| 1068 | device_unregister(dev); |
Linus Walleij | 9fb1f39 | 2013-12-04 14:42:46 +0100 | [diff] [blame] | 1069 | chip->exported = false; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1070 | status = 0; |
| 1071 | } else |
| 1072 | status = -ENODEV; |
| 1073 | mutex_unlock(&sysfs_lock); |
| 1074 | |
| 1075 | if (status) |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 1076 | chip_dbg(chip, "%s: status %d\n", __func__, status); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1077 | } |
| 1078 | |
| 1079 | static int __init gpiolib_sysfs_init(void) |
| 1080 | { |
| 1081 | int status; |
| 1082 | unsigned long flags; |
Alexandre Courbot | 65493e3 | 2013-02-03 01:29:25 +0900 | [diff] [blame] | 1083 | struct gpio_chip *chip; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1084 | |
| 1085 | status = class_register(&gpio_class); |
| 1086 | if (status < 0) |
| 1087 | return status; |
| 1088 | |
| 1089 | /* Scan and register the gpio_chips which registered very |
| 1090 | * early (e.g. before the class_register above was called). |
| 1091 | * |
| 1092 | * We run before arch_initcall() so chip->dev nodes can have |
| 1093 | * registered, and so arch_initcall() can always gpio_export(). |
| 1094 | */ |
| 1095 | spin_lock_irqsave(&gpio_lock, flags); |
Alexandre Courbot | 65493e3 | 2013-02-03 01:29:25 +0900 | [diff] [blame] | 1096 | list_for_each_entry(chip, &gpio_chips, list) { |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1097 | if (!chip || chip->exported) |
| 1098 | continue; |
| 1099 | |
| 1100 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1101 | status = gpiochip_export(chip); |
| 1102 | spin_lock_irqsave(&gpio_lock, flags); |
| 1103 | } |
| 1104 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1105 | |
| 1106 | |
| 1107 | return status; |
| 1108 | } |
| 1109 | postcore_initcall(gpiolib_sysfs_init); |
| 1110 | |
| 1111 | #else |
| 1112 | static inline int gpiochip_export(struct gpio_chip *chip) |
| 1113 | { |
| 1114 | return 0; |
| 1115 | } |
| 1116 | |
| 1117 | static inline void gpiochip_unexport(struct gpio_chip *chip) |
| 1118 | { |
| 1119 | } |
| 1120 | |
| 1121 | #endif /* CONFIG_GPIO_SYSFS */ |
| 1122 | |
Alexandre Courbot | 1a989d0 | 2013-02-03 01:29:24 +0900 | [diff] [blame] | 1123 | /* |
| 1124 | * Add a new chip to the global chips list, keeping the list of chips sorted |
| 1125 | * by base order. |
| 1126 | * |
| 1127 | * Return -EBUSY if the new chip overlaps with some other chip's integer |
| 1128 | * space. |
| 1129 | */ |
| 1130 | static int gpiochip_add_to_list(struct gpio_chip *chip) |
| 1131 | { |
| 1132 | struct list_head *pos = &gpio_chips; |
| 1133 | struct gpio_chip *_chip; |
| 1134 | int err = 0; |
| 1135 | |
| 1136 | /* find where to insert our chip */ |
| 1137 | list_for_each(pos, &gpio_chips) { |
| 1138 | _chip = list_entry(pos, struct gpio_chip, list); |
| 1139 | /* shall we insert before _chip? */ |
| 1140 | if (_chip->base >= chip->base + chip->ngpio) |
| 1141 | break; |
| 1142 | } |
| 1143 | |
| 1144 | /* are we stepping on the chip right before? */ |
| 1145 | if (pos != &gpio_chips && pos->prev != &gpio_chips) { |
| 1146 | _chip = list_entry(pos->prev, struct gpio_chip, list); |
| 1147 | if (_chip->base + _chip->ngpio > chip->base) { |
| 1148 | dev_err(chip->dev, |
| 1149 | "GPIO integer space overlap, cannot add chip\n"); |
| 1150 | err = -EBUSY; |
| 1151 | } |
| 1152 | } |
| 1153 | |
| 1154 | if (!err) |
| 1155 | list_add_tail(&chip->list, pos); |
| 1156 | |
| 1157 | return err; |
| 1158 | } |
| 1159 | |
Anton Vorontsov | 169b6a7 | 2008-04-28 02:14:47 -0700 | [diff] [blame] | 1160 | /** |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1161 | * gpiochip_add() - register a gpio_chip |
| 1162 | * @chip: the chip to register, with chip->base initialized |
| 1163 | * Context: potentially before irqs or kmalloc will work |
| 1164 | * |
| 1165 | * Returns a negative errno if the chip can't be registered, such as |
| 1166 | * because the chip->base is invalid or already associated with a |
| 1167 | * different chip. Otherwise it returns zero as a success code. |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 1168 | * |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1169 | * When gpiochip_add() is called very early during boot, so that GPIOs |
| 1170 | * can be freely used, the chip->dev device must be registered before |
| 1171 | * the gpio framework's arch_initcall(). Otherwise sysfs initialization |
| 1172 | * for GPIOs will fail rudely. |
| 1173 | * |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 1174 | * If chip->base is negative, this requests dynamic assignment of |
| 1175 | * a range of valid GPIOs. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1176 | */ |
| 1177 | int gpiochip_add(struct gpio_chip *chip) |
| 1178 | { |
| 1179 | unsigned long flags; |
| 1180 | int status = 0; |
| 1181 | unsigned id; |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 1182 | int base = chip->base; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1183 | |
Trent Piepho | bff5fda | 2008-05-23 13:04:44 -0700 | [diff] [blame] | 1184 | if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio - 1)) |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 1185 | && base >= 0) { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1186 | status = -EINVAL; |
| 1187 | goto fail; |
| 1188 | } |
| 1189 | |
| 1190 | spin_lock_irqsave(&gpio_lock, flags); |
| 1191 | |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 1192 | if (base < 0) { |
| 1193 | base = gpiochip_find_base(chip->ngpio); |
| 1194 | if (base < 0) { |
| 1195 | status = base; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1196 | goto unlock; |
Anton Vorontsov | 8d0aab2 | 2008-04-28 02:14:46 -0700 | [diff] [blame] | 1197 | } |
| 1198 | chip->base = base; |
| 1199 | } |
| 1200 | |
Alexandre Courbot | 1a989d0 | 2013-02-03 01:29:24 +0900 | [diff] [blame] | 1201 | status = gpiochip_add_to_list(chip); |
| 1202 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1203 | if (status == 0) { |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1204 | chip->desc = &gpio_desc[chip->base]; |
| 1205 | |
| 1206 | for (id = 0; id < chip->ngpio; id++) { |
| 1207 | struct gpio_desc *desc = &chip->desc[id]; |
| 1208 | desc->chip = chip; |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1209 | |
| 1210 | /* REVISIT: most hardware initializes GPIOs as |
| 1211 | * inputs (often with pullups enabled) so power |
| 1212 | * usage is minimized. Linux code should set the |
| 1213 | * gpio direction first thing; but until it does, |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 1214 | * and in case chip->get_direction is not set, |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1215 | * we may expose the wrong direction in sysfs. |
| 1216 | */ |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1217 | desc->flags = !chip->direction_input |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1218 | ? (1 << FLAG_IS_OUT) |
| 1219 | : 0; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1220 | } |
| 1221 | } |
| 1222 | |
Zhangfei Gao | 3bae481 | 2013-06-09 11:08:32 +0800 | [diff] [blame] | 1223 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1224 | |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1225 | #ifdef CONFIG_PINCTRL |
| 1226 | INIT_LIST_HEAD(&chip->pin_ranges); |
| 1227 | #endif |
| 1228 | |
Anton Vorontsov | 391c970 | 2010-06-08 07:48:17 -0600 | [diff] [blame] | 1229 | of_gpiochip_add(chip); |
Mika Westerberg | 664e3e5 | 2014-01-08 12:40:54 +0200 | [diff] [blame] | 1230 | acpi_gpiochip_add(chip); |
Anton Vorontsov | 391c970 | 2010-06-08 07:48:17 -0600 | [diff] [blame] | 1231 | |
Anton Vorontsov | cedb188 | 2010-06-08 07:48:15 -0600 | [diff] [blame] | 1232 | if (status) |
| 1233 | goto fail; |
| 1234 | |
| 1235 | status = gpiochip_export(chip); |
| 1236 | if (status) |
| 1237 | goto fail; |
| 1238 | |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1239 | pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
Grant Likely | 64842aa | 2011-11-06 11:36:18 -0700 | [diff] [blame] | 1240 | chip->base, chip->base + chip->ngpio - 1, |
| 1241 | chip->label ? : "generic"); |
| 1242 | |
Anton Vorontsov | cedb188 | 2010-06-08 07:48:15 -0600 | [diff] [blame] | 1243 | return 0; |
Zhangfei Gao | 3bae481 | 2013-06-09 11:08:32 +0800 | [diff] [blame] | 1244 | |
| 1245 | unlock: |
| 1246 | spin_unlock_irqrestore(&gpio_lock, flags); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1247 | fail: |
| 1248 | /* failures here can mean systems won't boot... */ |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1249 | pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
Anton Vorontsov | cedb188 | 2010-06-08 07:48:15 -0600 | [diff] [blame] | 1250 | chip->base, chip->base + chip->ngpio - 1, |
| 1251 | chip->label ? : "generic"); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1252 | return status; |
| 1253 | } |
| 1254 | EXPORT_SYMBOL_GPL(gpiochip_add); |
| 1255 | |
| 1256 | /** |
| 1257 | * gpiochip_remove() - unregister a gpio_chip |
| 1258 | * @chip: the chip to unregister |
| 1259 | * |
| 1260 | * A gpio_chip with any GPIOs still requested may not be removed. |
| 1261 | */ |
| 1262 | int gpiochip_remove(struct gpio_chip *chip) |
| 1263 | { |
| 1264 | unsigned long flags; |
| 1265 | int status = 0; |
| 1266 | unsigned id; |
| 1267 | |
| 1268 | spin_lock_irqsave(&gpio_lock, flags); |
| 1269 | |
Linus Walleij | 9ef0d6f | 2012-11-06 15:15:44 +0100 | [diff] [blame] | 1270 | gpiochip_remove_pin_ranges(chip); |
Anton Vorontsov | 391c970 | 2010-06-08 07:48:17 -0600 | [diff] [blame] | 1271 | of_gpiochip_remove(chip); |
Mika Westerberg | 664e3e5 | 2014-01-08 12:40:54 +0200 | [diff] [blame] | 1272 | acpi_gpiochip_remove(chip); |
Anton Vorontsov | 391c970 | 2010-06-08 07:48:17 -0600 | [diff] [blame] | 1273 | |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1274 | for (id = 0; id < chip->ngpio; id++) { |
| 1275 | if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1276 | status = -EBUSY; |
| 1277 | break; |
| 1278 | } |
| 1279 | } |
| 1280 | if (status == 0) { |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1281 | for (id = 0; id < chip->ngpio; id++) |
| 1282 | chip->desc[id].chip = NULL; |
Alexandre Courbot | 1a989d0 | 2013-02-03 01:29:24 +0900 | [diff] [blame] | 1283 | |
| 1284 | list_del(&chip->list); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1285 | } |
| 1286 | |
| 1287 | spin_unlock_irqrestore(&gpio_lock, flags); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1288 | |
| 1289 | if (status == 0) |
| 1290 | gpiochip_unexport(chip); |
| 1291 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1292 | return status; |
| 1293 | } |
| 1294 | EXPORT_SYMBOL_GPL(gpiochip_remove); |
| 1295 | |
Grant Likely | 594fa26 | 2010-06-08 07:48:16 -0600 | [diff] [blame] | 1296 | /** |
| 1297 | * gpiochip_find() - iterator for locating a specific gpio_chip |
| 1298 | * @data: data to pass to match function |
| 1299 | * @callback: Callback function to check gpio_chip |
| 1300 | * |
| 1301 | * Similar to bus_find_device. It returns a reference to a gpio_chip as |
| 1302 | * determined by a user supplied @match callback. The callback should return |
| 1303 | * 0 if the device doesn't match and non-zero if it does. If the callback is |
| 1304 | * non-zero, this function will return to the caller and not iterate over any |
| 1305 | * more gpio_chips. |
| 1306 | */ |
Grant Likely | 07ce8ec | 2012-05-18 23:01:05 -0600 | [diff] [blame] | 1307 | struct gpio_chip *gpiochip_find(void *data, |
Grant Likely | 6e2cf65 | 2012-03-02 15:56:03 -0700 | [diff] [blame] | 1308 | int (*match)(struct gpio_chip *chip, |
Grant Likely | 3d0f7cf0 | 2012-05-17 13:54:40 -0600 | [diff] [blame] | 1309 | void *data)) |
Grant Likely | 594fa26 | 2010-06-08 07:48:16 -0600 | [diff] [blame] | 1310 | { |
Alexandre Courbot | 125eef9 | 2013-02-03 01:29:26 +0900 | [diff] [blame] | 1311 | struct gpio_chip *chip; |
Grant Likely | 594fa26 | 2010-06-08 07:48:16 -0600 | [diff] [blame] | 1312 | unsigned long flags; |
Grant Likely | 594fa26 | 2010-06-08 07:48:16 -0600 | [diff] [blame] | 1313 | |
| 1314 | spin_lock_irqsave(&gpio_lock, flags); |
Alexandre Courbot | 125eef9 | 2013-02-03 01:29:26 +0900 | [diff] [blame] | 1315 | list_for_each_entry(chip, &gpio_chips, list) |
| 1316 | if (match(chip, data)) |
Grant Likely | 594fa26 | 2010-06-08 07:48:16 -0600 | [diff] [blame] | 1317 | break; |
Alexandre Courbot | 125eef9 | 2013-02-03 01:29:26 +0900 | [diff] [blame] | 1318 | |
| 1319 | /* No match? */ |
| 1320 | if (&chip->list == &gpio_chips) |
| 1321 | chip = NULL; |
Grant Likely | 594fa26 | 2010-06-08 07:48:16 -0600 | [diff] [blame] | 1322 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1323 | |
| 1324 | return chip; |
| 1325 | } |
Jean Delvare | 8fa0c9b | 2011-05-20 00:40:18 -0600 | [diff] [blame] | 1326 | EXPORT_SYMBOL_GPL(gpiochip_find); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1327 | |
Alexandre Courbot | 79697ef | 2013-11-16 21:39:32 +0900 | [diff] [blame] | 1328 | static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
| 1329 | { |
| 1330 | const char *name = data; |
| 1331 | |
| 1332 | return !strcmp(chip->label, name); |
| 1333 | } |
| 1334 | |
| 1335 | static struct gpio_chip *find_chip_by_name(const char *name) |
| 1336 | { |
| 1337 | return gpiochip_find((void *)name, gpiochip_match_name); |
| 1338 | } |
| 1339 | |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1340 | #ifdef CONFIG_PINCTRL |
Linus Walleij | 165adc9 | 2012-11-06 14:49:39 +0100 | [diff] [blame] | 1341 | |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1342 | /** |
Christian Ruppert | 586a87e | 2013-10-15 15:37:54 +0200 | [diff] [blame] | 1343 | * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping |
| 1344 | * @chip: the gpiochip to add the range for |
| 1345 | * @pinctrl: the dev_name() of the pin controller to map to |
| 1346 | * @gpio_offset: the start offset in the current gpio_chip number space |
| 1347 | * @pin_group: name of the pin group inside the pin controller |
| 1348 | */ |
| 1349 | int gpiochip_add_pingroup_range(struct gpio_chip *chip, |
| 1350 | struct pinctrl_dev *pctldev, |
| 1351 | unsigned int gpio_offset, const char *pin_group) |
| 1352 | { |
| 1353 | struct gpio_pin_range *pin_range; |
| 1354 | int ret; |
| 1355 | |
| 1356 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
| 1357 | if (!pin_range) { |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 1358 | chip_err(chip, "failed to allocate pin ranges\n"); |
Christian Ruppert | 586a87e | 2013-10-15 15:37:54 +0200 | [diff] [blame] | 1359 | return -ENOMEM; |
| 1360 | } |
| 1361 | |
| 1362 | /* Use local offset as range ID */ |
| 1363 | pin_range->range.id = gpio_offset; |
| 1364 | pin_range->range.gc = chip; |
| 1365 | pin_range->range.name = chip->label; |
| 1366 | pin_range->range.base = chip->base + gpio_offset; |
| 1367 | pin_range->pctldev = pctldev; |
| 1368 | |
| 1369 | ret = pinctrl_get_group_pins(pctldev, pin_group, |
| 1370 | &pin_range->range.pins, |
| 1371 | &pin_range->range.npins); |
Michal Nazarewicz | 61c6375 | 2013-11-13 21:20:39 +0100 | [diff] [blame] | 1372 | if (ret < 0) { |
| 1373 | kfree(pin_range); |
Christian Ruppert | 586a87e | 2013-10-15 15:37:54 +0200 | [diff] [blame] | 1374 | return ret; |
Michal Nazarewicz | 61c6375 | 2013-11-13 21:20:39 +0100 | [diff] [blame] | 1375 | } |
Christian Ruppert | 586a87e | 2013-10-15 15:37:54 +0200 | [diff] [blame] | 1376 | |
| 1377 | pinctrl_add_gpio_range(pctldev, &pin_range->range); |
| 1378 | |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 1379 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
| 1380 | gpio_offset, gpio_offset + pin_range->range.npins - 1, |
Christian Ruppert | 586a87e | 2013-10-15 15:37:54 +0200 | [diff] [blame] | 1381 | pinctrl_dev_get_devname(pctldev), pin_group); |
| 1382 | |
| 1383 | list_add_tail(&pin_range->node, &chip->pin_ranges); |
| 1384 | |
| 1385 | return 0; |
| 1386 | } |
| 1387 | EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); |
| 1388 | |
| 1389 | /** |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1390 | * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping |
| 1391 | * @chip: the gpiochip to add the range for |
| 1392 | * @pinctrl_name: the dev_name() of the pin controller to map to |
Linus Walleij | 316511c | 2012-11-21 08:48:09 +0100 | [diff] [blame] | 1393 | * @gpio_offset: the start offset in the current gpio_chip number space |
| 1394 | * @pin_offset: the start offset in the pin controller number space |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1395 | * @npins: the number of pins from the offset of each pin space (GPIO and |
| 1396 | * pin controller) to accumulate in this range |
| 1397 | */ |
Linus Walleij | 1e63d7b | 2012-11-06 16:03:35 +0100 | [diff] [blame] | 1398 | int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
Linus Walleij | 316511c | 2012-11-21 08:48:09 +0100 | [diff] [blame] | 1399 | unsigned int gpio_offset, unsigned int pin_offset, |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1400 | unsigned int npins) |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1401 | { |
| 1402 | struct gpio_pin_range *pin_range; |
Axel Lin | b4d4b1f | 2012-11-21 14:33:56 +0800 | [diff] [blame] | 1403 | int ret; |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1404 | |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1405 | pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1406 | if (!pin_range) { |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 1407 | chip_err(chip, "failed to allocate pin ranges\n"); |
Linus Walleij | 1e63d7b | 2012-11-06 16:03:35 +0100 | [diff] [blame] | 1408 | return -ENOMEM; |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1409 | } |
| 1410 | |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1411 | /* Use local offset as range ID */ |
Linus Walleij | 316511c | 2012-11-21 08:48:09 +0100 | [diff] [blame] | 1412 | pin_range->range.id = gpio_offset; |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1413 | pin_range->range.gc = chip; |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1414 | pin_range->range.name = chip->label; |
Linus Walleij | 316511c | 2012-11-21 08:48:09 +0100 | [diff] [blame] | 1415 | pin_range->range.base = chip->base + gpio_offset; |
| 1416 | pin_range->range.pin_base = pin_offset; |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1417 | pin_range->range.npins = npins; |
Linus Walleij | 192c369 | 2012-11-20 14:03:37 +0100 | [diff] [blame] | 1418 | pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1419 | &pin_range->range); |
Linus Walleij | 8f23ca1 | 2012-11-20 14:56:25 +0100 | [diff] [blame] | 1420 | if (IS_ERR(pin_range->pctldev)) { |
Axel Lin | b4d4b1f | 2012-11-21 14:33:56 +0800 | [diff] [blame] | 1421 | ret = PTR_ERR(pin_range->pctldev); |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 1422 | chip_err(chip, "could not create pin range\n"); |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1423 | kfree(pin_range); |
Axel Lin | b4d4b1f | 2012-11-21 14:33:56 +0800 | [diff] [blame] | 1424 | return ret; |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1425 | } |
Andy Shevchenko | 1a2a99c | 2013-12-05 11:26:24 +0200 | [diff] [blame] | 1426 | chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
| 1427 | gpio_offset, gpio_offset + npins - 1, |
Linus Walleij | 316511c | 2012-11-21 08:48:09 +0100 | [diff] [blame] | 1428 | pinctl_name, |
| 1429 | pin_offset, pin_offset + npins - 1); |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1430 | |
| 1431 | list_add_tail(&pin_range->node, &chip->pin_ranges); |
Linus Walleij | 1e63d7b | 2012-11-06 16:03:35 +0100 | [diff] [blame] | 1432 | |
| 1433 | return 0; |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1434 | } |
Linus Walleij | 165adc9 | 2012-11-06 14:49:39 +0100 | [diff] [blame] | 1435 | EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1436 | |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1437 | /** |
| 1438 | * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings |
| 1439 | * @chip: the chip to remove all the mappings for |
| 1440 | */ |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1441 | void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
| 1442 | { |
| 1443 | struct gpio_pin_range *pin_range, *tmp; |
| 1444 | |
| 1445 | list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { |
| 1446 | list_del(&pin_range->node); |
| 1447 | pinctrl_remove_gpio_range(pin_range->pctldev, |
| 1448 | &pin_range->range); |
Linus Walleij | 3f0f867 | 2012-11-20 12:40:15 +0100 | [diff] [blame] | 1449 | kfree(pin_range); |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1450 | } |
| 1451 | } |
Linus Walleij | 165adc9 | 2012-11-06 14:49:39 +0100 | [diff] [blame] | 1452 | EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
| 1453 | |
| 1454 | #endif /* CONFIG_PINCTRL */ |
Shiraz Hashim | f23f151 | 2012-10-27 15:21:36 +0530 | [diff] [blame] | 1455 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1456 | /* These "optional" allocation calls help prevent drivers from stomping |
| 1457 | * on each other, and help provide better diagnostics in debugfs. |
| 1458 | * They're called even less than the "set direction" calls. |
| 1459 | */ |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1460 | static int gpiod_request(struct gpio_desc *desc, const char *label) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1461 | { |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1462 | struct gpio_chip *chip; |
Mark Brown | e935457 | 2012-07-09 12:22:56 +0100 | [diff] [blame] | 1463 | int status = -EPROBE_DEFER; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1464 | unsigned long flags; |
| 1465 | |
Alexandre Courbot | 0204df4 | 2013-10-04 10:59:58 -0700 | [diff] [blame] | 1466 | if (!desc) { |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1467 | pr_warn("%s: invalid GPIO\n", __func__); |
| 1468 | return -EINVAL; |
| 1469 | } |
| 1470 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1471 | spin_lock_irqsave(&gpio_lock, flags); |
| 1472 | |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1473 | chip = desc->chip; |
Alexandre Courbot | 0204df4 | 2013-10-04 10:59:58 -0700 | [diff] [blame] | 1474 | if (chip == NULL) |
| 1475 | goto done; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1476 | |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1477 | if (!try_module_get(chip->owner)) |
Guennadi Liakhovetski | 438d890 | 2008-04-28 02:14:44 -0700 | [diff] [blame] | 1478 | goto done; |
| 1479 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1480 | /* NOTE: gpio_request() can be called in early boot, |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1481 | * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1482 | */ |
| 1483 | |
| 1484 | if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { |
| 1485 | desc_set_label(desc, label ? : "?"); |
| 1486 | status = 0; |
Guennadi Liakhovetski | 438d890 | 2008-04-28 02:14:44 -0700 | [diff] [blame] | 1487 | } else { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1488 | status = -EBUSY; |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1489 | module_put(chip->owner); |
Magnus Damm | 7460db5 | 2009-01-29 14:25:12 -0800 | [diff] [blame] | 1490 | goto done; |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1491 | } |
| 1492 | |
| 1493 | if (chip->request) { |
| 1494 | /* chip->request may sleep */ |
| 1495 | spin_unlock_irqrestore(&gpio_lock, flags); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1496 | status = chip->request(chip, gpio_chip_hwgpio(desc)); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1497 | spin_lock_irqsave(&gpio_lock, flags); |
| 1498 | |
| 1499 | if (status < 0) { |
| 1500 | desc_set_label(desc, NULL); |
| 1501 | module_put(chip->owner); |
| 1502 | clear_bit(FLAG_REQUESTED, &desc->flags); |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 1503 | goto done; |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1504 | } |
Guennadi Liakhovetski | 438d890 | 2008-04-28 02:14:44 -0700 | [diff] [blame] | 1505 | } |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 1506 | if (chip->get_direction) { |
| 1507 | /* chip->get_direction may sleep */ |
| 1508 | spin_unlock_irqrestore(&gpio_lock, flags); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1509 | gpiod_get_direction(desc); |
Mathias Nyman | 80b0a60 | 2012-10-24 17:25:27 +0300 | [diff] [blame] | 1510 | spin_lock_irqsave(&gpio_lock, flags); |
| 1511 | } |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1512 | done: |
| 1513 | if (status) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1514 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1515 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1516 | return status; |
| 1517 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1518 | |
| 1519 | int gpio_request(unsigned gpio, const char *label) |
| 1520 | { |
| 1521 | return gpiod_request(gpio_to_desc(gpio), label); |
| 1522 | } |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1523 | EXPORT_SYMBOL_GPL(gpio_request); |
| 1524 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1525 | static void gpiod_free(struct gpio_desc *desc) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1526 | { |
| 1527 | unsigned long flags; |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1528 | struct gpio_chip *chip; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1529 | |
Uwe Kleine-König | 3d599d1 | 2008-10-15 22:03:12 -0700 | [diff] [blame] | 1530 | might_sleep(); |
| 1531 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1532 | if (!desc) { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1533 | WARN_ON(extra_checks); |
| 1534 | return; |
| 1535 | } |
| 1536 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1537 | gpiod_unexport(desc); |
David Brownell | d8f388d8 | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 1538 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1539 | spin_lock_irqsave(&gpio_lock, flags); |
| 1540 | |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1541 | chip = desc->chip; |
| 1542 | if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { |
| 1543 | if (chip->free) { |
| 1544 | spin_unlock_irqrestore(&gpio_lock, flags); |
David Brownell | 9c4ba94 | 2010-08-10 18:02:24 -0700 | [diff] [blame] | 1545 | might_sleep_if(chip->can_sleep); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1546 | chip->free(chip, gpio_chip_hwgpio(desc)); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1547 | spin_lock_irqsave(&gpio_lock, flags); |
| 1548 | } |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1549 | desc_set_label(desc, NULL); |
Guennadi Liakhovetski | 438d890 | 2008-04-28 02:14:44 -0700 | [diff] [blame] | 1550 | module_put(desc->chip->owner); |
Jani Nikula | 0769746 | 2009-12-15 16:46:20 -0800 | [diff] [blame] | 1551 | clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1552 | clear_bit(FLAG_REQUESTED, &desc->flags); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1553 | clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 1554 | clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
Guennadi Liakhovetski | 438d890 | 2008-04-28 02:14:44 -0700 | [diff] [blame] | 1555 | } else |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1556 | WARN_ON(extra_checks); |
| 1557 | |
| 1558 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1559 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1560 | |
| 1561 | void gpio_free(unsigned gpio) |
| 1562 | { |
| 1563 | gpiod_free(gpio_to_desc(gpio)); |
| 1564 | } |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1565 | EXPORT_SYMBOL_GPL(gpio_free); |
| 1566 | |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1567 | /** |
| 1568 | * gpio_request_one - request a single GPIO with initial configuration |
| 1569 | * @gpio: the GPIO number |
| 1570 | * @flags: GPIO configuration as specified by GPIOF_* |
| 1571 | * @label: a literal description string of this GPIO |
| 1572 | */ |
| 1573 | int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) |
| 1574 | { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1575 | struct gpio_desc *desc; |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1576 | int err; |
| 1577 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1578 | desc = gpio_to_desc(gpio); |
| 1579 | |
| 1580 | err = gpiod_request(desc, label); |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1581 | if (err) |
| 1582 | return err; |
| 1583 | |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1584 | if (flags & GPIOF_OPEN_DRAIN) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1585 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1586 | |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 1587 | if (flags & GPIOF_OPEN_SOURCE) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1588 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 1589 | |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1590 | if (flags & GPIOF_DIR_IN) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1591 | err = gpiod_direction_input(desc); |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1592 | else |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1593 | err = gpiod_direction_output(desc, |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1594 | (flags & GPIOF_INIT_HIGH) ? 1 : 0); |
| 1595 | |
Aaro Koskinen | e254811 | 2010-12-21 17:24:22 -0800 | [diff] [blame] | 1596 | if (err) |
Wolfram Sang | fc3a1f0 | 2011-12-13 18:34:01 +0100 | [diff] [blame] | 1597 | goto free_gpio; |
Aaro Koskinen | e254811 | 2010-12-21 17:24:22 -0800 | [diff] [blame] | 1598 | |
Wolfram Sang | fc3a1f0 | 2011-12-13 18:34:01 +0100 | [diff] [blame] | 1599 | if (flags & GPIOF_EXPORT) { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1600 | err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE); |
Wolfram Sang | fc3a1f0 | 2011-12-13 18:34:01 +0100 | [diff] [blame] | 1601 | if (err) |
| 1602 | goto free_gpio; |
| 1603 | } |
| 1604 | |
| 1605 | return 0; |
| 1606 | |
| 1607 | free_gpio: |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1608 | gpiod_free(desc); |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1609 | return err; |
| 1610 | } |
| 1611 | EXPORT_SYMBOL_GPL(gpio_request_one); |
| 1612 | |
| 1613 | /** |
| 1614 | * gpio_request_array - request multiple GPIOs in a single call |
| 1615 | * @array: array of the 'struct gpio' |
| 1616 | * @num: how many GPIOs in the array |
| 1617 | */ |
Lars-Peter Clausen | 7c29597 | 2011-05-25 16:20:31 -0700 | [diff] [blame] | 1618 | int gpio_request_array(const struct gpio *array, size_t num) |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1619 | { |
| 1620 | int i, err; |
| 1621 | |
| 1622 | for (i = 0; i < num; i++, array++) { |
| 1623 | err = gpio_request_one(array->gpio, array->flags, array->label); |
| 1624 | if (err) |
| 1625 | goto err_free; |
| 1626 | } |
| 1627 | return 0; |
| 1628 | |
| 1629 | err_free: |
| 1630 | while (i--) |
| 1631 | gpio_free((--array)->gpio); |
| 1632 | return err; |
| 1633 | } |
| 1634 | EXPORT_SYMBOL_GPL(gpio_request_array); |
| 1635 | |
| 1636 | /** |
| 1637 | * gpio_free_array - release multiple GPIOs in a single call |
| 1638 | * @array: array of the 'struct gpio' |
| 1639 | * @num: how many GPIOs in the array |
| 1640 | */ |
Lars-Peter Clausen | 7c29597 | 2011-05-25 16:20:31 -0700 | [diff] [blame] | 1641 | void gpio_free_array(const struct gpio *array, size_t num) |
Eric Miao | 3e45f1d | 2010-03-05 13:44:35 -0800 | [diff] [blame] | 1642 | { |
| 1643 | while (num--) |
| 1644 | gpio_free((array++)->gpio); |
| 1645 | } |
| 1646 | EXPORT_SYMBOL_GPL(gpio_free_array); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1647 | |
| 1648 | /** |
| 1649 | * gpiochip_is_requested - return string iff signal was requested |
| 1650 | * @chip: controller managing the signal |
| 1651 | * @offset: of signal within controller's 0..(ngpio - 1) range |
| 1652 | * |
| 1653 | * Returns NULL if the GPIO is not currently requested, else a string. |
| 1654 | * If debugfs support is enabled, the string returned is the label passed |
| 1655 | * to gpio_request(); otherwise it is a meaningless constant. |
| 1656 | * |
| 1657 | * This function is for use by GPIO controller drivers. The label can |
| 1658 | * help with diagnostics, and knowing that the signal is used as a GPIO |
| 1659 | * can help avoid accidentally multiplexing it to another controller. |
| 1660 | */ |
| 1661 | const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) |
| 1662 | { |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1663 | struct gpio_desc *desc; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1664 | |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1665 | if (!GPIO_OFFSET_VALID(chip, offset)) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1666 | return NULL; |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 1667 | |
| 1668 | desc = &chip->desc[offset]; |
| 1669 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1670 | if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1671 | return NULL; |
| 1672 | #ifdef CONFIG_DEBUG_FS |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1673 | return desc->label; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1674 | #else |
| 1675 | return "?"; |
| 1676 | #endif |
| 1677 | } |
| 1678 | EXPORT_SYMBOL_GPL(gpiochip_is_requested); |
| 1679 | |
| 1680 | |
| 1681 | /* Drivers MUST set GPIO direction before making get/set calls. In |
| 1682 | * some cases this is done in early boot, before IRQs are enabled. |
| 1683 | * |
| 1684 | * As a rule these aren't called more than once (except for drivers |
| 1685 | * using the open-drain emulation idiom) so these are natural places |
| 1686 | * to accumulate extra debugging checks. Note that we can't (yet) |
| 1687 | * rely on gpio_request() having been called beforehand. |
| 1688 | */ |
| 1689 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1690 | /** |
| 1691 | * gpiod_direction_input - set the GPIO direction to input |
| 1692 | * @desc: GPIO to set to input |
| 1693 | * |
| 1694 | * Set the direction of the passed GPIO to input, such as gpiod_get_value() can |
| 1695 | * be called safely on it. |
| 1696 | * |
| 1697 | * Return 0 in case of success, else an error code. |
| 1698 | */ |
| 1699 | int gpiod_direction_input(struct gpio_desc *desc) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1700 | { |
| 1701 | unsigned long flags; |
| 1702 | struct gpio_chip *chip; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1703 | int status = -EINVAL; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1704 | int offset; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1705 | |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1706 | if (!desc || !desc->chip) { |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1707 | pr_warn("%s: invalid GPIO\n", __func__); |
| 1708 | return -EINVAL; |
| 1709 | } |
| 1710 | |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1711 | chip = desc->chip; |
| 1712 | if (!chip->get || !chip->direction_input) { |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 1713 | gpiod_warn(desc, |
| 1714 | "%s: missing get() or direction_input() operations\n", |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1715 | __func__); |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1716 | return -EIO; |
| 1717 | } |
| 1718 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1719 | spin_lock_irqsave(&gpio_lock, flags); |
| 1720 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1721 | status = gpio_ensure_requested(desc); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1722 | if (status < 0) |
| 1723 | goto fail; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1724 | |
| 1725 | /* now we know the gpio is valid and chip won't vanish */ |
| 1726 | |
| 1727 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1728 | |
David Brownell | 9c4ba94 | 2010-08-10 18:02:24 -0700 | [diff] [blame] | 1729 | might_sleep_if(chip->can_sleep); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1730 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1731 | offset = gpio_chip_hwgpio(desc); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1732 | if (status) { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1733 | status = chip->request(chip, offset); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1734 | if (status < 0) { |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1735 | gpiod_dbg(desc, "%s: chip request fail, %d\n", |
| 1736 | __func__, status); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1737 | /* and it's not available to anyone else ... |
| 1738 | * gpio_request() is the fully clean solution. |
| 1739 | */ |
| 1740 | goto lose; |
| 1741 | } |
| 1742 | } |
| 1743 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1744 | status = chip->direction_input(chip, offset); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1745 | if (status == 0) |
| 1746 | clear_bit(FLAG_IS_OUT, &desc->flags); |
Uwe Kleine-König | 3f397c21 | 2011-05-20 00:40:19 -0600 | [diff] [blame] | 1747 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1748 | trace_gpio_direction(desc_to_gpio(desc), 1, status); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1749 | lose: |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1750 | return status; |
| 1751 | fail: |
| 1752 | spin_unlock_irqrestore(&gpio_lock, flags); |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1753 | if (status) |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1754 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1755 | return status; |
| 1756 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1757 | EXPORT_SYMBOL_GPL(gpiod_direction_input); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1758 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1759 | /** |
| 1760 | * gpiod_direction_output - set the GPIO direction to input |
| 1761 | * @desc: GPIO to set to output |
| 1762 | * @value: initial output value of the GPIO |
| 1763 | * |
| 1764 | * Set the direction of the passed GPIO to output, such as gpiod_set_value() can |
| 1765 | * be called safely on it. The initial value of the output must be specified. |
| 1766 | * |
| 1767 | * Return 0 in case of success, else an error code. |
| 1768 | */ |
| 1769 | int gpiod_direction_output(struct gpio_desc *desc, int value) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1770 | { |
| 1771 | unsigned long flags; |
| 1772 | struct gpio_chip *chip; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1773 | int status = -EINVAL; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1774 | int offset; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1775 | |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1776 | if (!desc || !desc->chip) { |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1777 | pr_warn("%s: invalid GPIO\n", __func__); |
| 1778 | return -EINVAL; |
| 1779 | } |
| 1780 | |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 1781 | /* GPIOs used for IRQs shall not be set as output */ |
| 1782 | if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { |
| 1783 | gpiod_err(desc, |
| 1784 | "%s: tried to set a GPIO tied to an IRQ as output\n", |
| 1785 | __func__); |
| 1786 | return -EIO; |
| 1787 | } |
| 1788 | |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1789 | /* Open drain pin should not be driven to 1 */ |
| 1790 | if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1791 | return gpiod_direction_input(desc); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1792 | |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 1793 | /* Open source pin should not be driven to 0 */ |
| 1794 | if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1795 | return gpiod_direction_input(desc); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 1796 | |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1797 | chip = desc->chip; |
| 1798 | if (!chip->set || !chip->direction_output) { |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 1799 | gpiod_warn(desc, |
| 1800 | "%s: missing set() or direction_output() operations\n", |
| 1801 | __func__); |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1802 | return -EIO; |
| 1803 | } |
| 1804 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1805 | spin_lock_irqsave(&gpio_lock, flags); |
| 1806 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1807 | status = gpio_ensure_requested(desc); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1808 | if (status < 0) |
| 1809 | goto fail; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1810 | |
| 1811 | /* now we know the gpio is valid and chip won't vanish */ |
| 1812 | |
| 1813 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1814 | |
David Brownell | 9c4ba94 | 2010-08-10 18:02:24 -0700 | [diff] [blame] | 1815 | might_sleep_if(chip->can_sleep); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1816 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1817 | offset = gpio_chip_hwgpio(desc); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1818 | if (status) { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1819 | status = chip->request(chip, offset); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1820 | if (status < 0) { |
Andy Shevchenko | 7589e59 | 2013-12-05 11:26:23 +0200 | [diff] [blame] | 1821 | gpiod_dbg(desc, "%s: chip request fail, %d\n", |
| 1822 | __func__, status); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1823 | /* and it's not available to anyone else ... |
| 1824 | * gpio_request() is the fully clean solution. |
| 1825 | */ |
| 1826 | goto lose; |
| 1827 | } |
| 1828 | } |
| 1829 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1830 | status = chip->direction_output(chip, offset, value); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1831 | if (status == 0) |
| 1832 | set_bit(FLAG_IS_OUT, &desc->flags); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1833 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
| 1834 | trace_gpio_direction(desc_to_gpio(desc), 0, status); |
David Brownell | 35e8bb5 | 2008-10-15 22:03:16 -0700 | [diff] [blame] | 1835 | lose: |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1836 | return status; |
| 1837 | fail: |
| 1838 | spin_unlock_irqrestore(&gpio_lock, flags); |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1839 | if (status) |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 1840 | gpiod_dbg(desc, "%s: gpio status %d\n", __func__, status); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1841 | return status; |
| 1842 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1843 | EXPORT_SYMBOL_GPL(gpiod_direction_output); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1844 | |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1845 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1846 | * gpiod_set_debounce - sets @debounce time for a @gpio |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1847 | * @gpio: the gpio to set debounce time |
| 1848 | * @debounce: debounce time is microseconds |
Linus Walleij | 65d8765 | 2013-09-04 14:17:08 +0200 | [diff] [blame] | 1849 | * |
| 1850 | * returns -ENOTSUPP if the controller does not support setting |
| 1851 | * debounce. |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1852 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1853 | int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1854 | { |
| 1855 | unsigned long flags; |
| 1856 | struct gpio_chip *chip; |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1857 | int status = -EINVAL; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1858 | int offset; |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1859 | |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1860 | if (!desc || !desc->chip) { |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1861 | pr_warn("%s: invalid GPIO\n", __func__); |
| 1862 | return -EINVAL; |
| 1863 | } |
| 1864 | |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1865 | chip = desc->chip; |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1866 | if (!chip->set || !chip->set_debounce) { |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 1867 | gpiod_dbg(desc, |
| 1868 | "%s: missing set() or set_debounce() operations\n", |
| 1869 | __func__); |
Linus Walleij | 65d8765 | 2013-09-04 14:17:08 +0200 | [diff] [blame] | 1870 | return -ENOTSUPP; |
Linus Walleij | be1a4b1 | 2013-08-30 09:41:45 +0200 | [diff] [blame] | 1871 | } |
| 1872 | |
| 1873 | spin_lock_irqsave(&gpio_lock, flags); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1874 | |
| 1875 | status = gpio_ensure_requested(desc); |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1876 | if (status < 0) |
| 1877 | goto fail; |
| 1878 | |
| 1879 | /* now we know the gpio is valid and chip won't vanish */ |
| 1880 | |
| 1881 | spin_unlock_irqrestore(&gpio_lock, flags); |
| 1882 | |
David Brownell | 9c4ba94 | 2010-08-10 18:02:24 -0700 | [diff] [blame] | 1883 | might_sleep_if(chip->can_sleep); |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1884 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1885 | offset = gpio_chip_hwgpio(desc); |
| 1886 | return chip->set_debounce(chip, offset, debounce); |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1887 | |
| 1888 | fail: |
| 1889 | spin_unlock_irqrestore(&gpio_lock, flags); |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 1890 | if (status) |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 1891 | gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
Felipe Balbi | c4b5be9 | 2010-05-26 14:42:23 -0700 | [diff] [blame] | 1892 | |
| 1893 | return status; |
| 1894 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1895 | EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1896 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1897 | /** |
| 1898 | * gpiod_is_active_low - test whether a GPIO is active-low or not |
| 1899 | * @desc: the gpio descriptor to test |
| 1900 | * |
| 1901 | * Returns 1 if the GPIO is active-low, 0 otherwise. |
| 1902 | */ |
| 1903 | int gpiod_is_active_low(const struct gpio_desc *desc) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1904 | { |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1905 | return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1906 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1907 | EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1908 | |
| 1909 | /* I/O calls are only valid after configuration completed; the relevant |
| 1910 | * "is this a valid GPIO" error checks should already have been done. |
| 1911 | * |
| 1912 | * "Get" operations are often inlinable as reading a pin value register, |
| 1913 | * and masking the relevant bit in that register. |
| 1914 | * |
| 1915 | * When "set" operations are inlinable, they involve writing that mask to |
| 1916 | * one register to set a low value, or a different register to set it high. |
| 1917 | * Otherwise locking is needed, so there may be little value to inlining. |
| 1918 | * |
| 1919 | *------------------------------------------------------------------------ |
| 1920 | * |
| 1921 | * IMPORTANT!!! The hot paths -- get/set value -- assume that callers |
| 1922 | * have requested the GPIO. That can include implicit requesting by |
| 1923 | * a direction setting call. Marking a gpio as requested locks its chip |
| 1924 | * in memory, guaranteeing that these table lookups need no more locking |
| 1925 | * and that gpiochip_remove() will fail. |
| 1926 | * |
| 1927 | * REVISIT when debugging, consider adding some instrumentation to ensure |
| 1928 | * that the GPIO was actually requested. |
| 1929 | */ |
| 1930 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1931 | static int _gpiod_get_raw_value(const struct gpio_desc *desc) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1932 | { |
| 1933 | struct gpio_chip *chip; |
Uwe Kleine-König | 3f397c21 | 2011-05-20 00:40:19 -0600 | [diff] [blame] | 1934 | int value; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1935 | int offset; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1936 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1937 | chip = desc->chip; |
| 1938 | offset = gpio_chip_hwgpio(desc); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1939 | value = chip->get ? chip->get(chip, offset) : 0; |
| 1940 | trace_gpio_value(desc_to_gpio(desc), 1, value); |
Uwe Kleine-König | 3f397c21 | 2011-05-20 00:40:19 -0600 | [diff] [blame] | 1941 | return value; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1942 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1943 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1944 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1945 | * gpiod_get_raw_value() - return a gpio's raw value |
| 1946 | * @desc: gpio whose value will be returned |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1947 | * |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1948 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
| 1949 | * its ACTIVE_LOW status. |
| 1950 | * |
| 1951 | * This function should be called from contexts where we cannot sleep, and will |
| 1952 | * complain if the GPIO chip functions potentially sleep. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1953 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1954 | int gpiod_get_raw_value(const struct gpio_desc *desc) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1955 | { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1956 | if (!desc) |
| 1957 | return 0; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1958 | /* Should be using gpio_get_value_cansleep() */ |
Alexandre Courbot | d8e0ac0 | 2013-09-04 20:29:25 +0900 | [diff] [blame] | 1959 | WARN_ON(desc->chip->can_sleep); |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1960 | return _gpiod_get_raw_value(desc); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1961 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1962 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1963 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1964 | /** |
| 1965 | * gpiod_get_value() - return a gpio's value |
| 1966 | * @desc: gpio whose value will be returned |
| 1967 | * |
| 1968 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into |
| 1969 | * account. |
| 1970 | * |
| 1971 | * This function should be called from contexts where we cannot sleep, and will |
| 1972 | * complain if the GPIO chip functions potentially sleep. |
| 1973 | */ |
| 1974 | int gpiod_get_value(const struct gpio_desc *desc) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1975 | { |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1976 | int value; |
| 1977 | if (!desc) |
| 1978 | return 0; |
| 1979 | /* Should be using gpio_get_value_cansleep() */ |
| 1980 | WARN_ON(desc->chip->can_sleep); |
| 1981 | |
| 1982 | value = _gpiod_get_raw_value(desc); |
| 1983 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| 1984 | value = !value; |
| 1985 | |
| 1986 | return value; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1987 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1988 | EXPORT_SYMBOL_GPL(gpiod_get_value); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 1989 | |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1990 | /* |
| 1991 | * _gpio_set_open_drain_value() - Set the open drain gpio's value. |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 1992 | * @desc: gpio descriptor whose state need to be set. |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1993 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
| 1994 | */ |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1995 | static void _gpio_set_open_drain_value(struct gpio_desc *desc, int value) |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 1996 | { |
| 1997 | int err = 0; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 1998 | struct gpio_chip *chip = desc->chip; |
| 1999 | int offset = gpio_chip_hwgpio(desc); |
| 2000 | |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2001 | if (value) { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2002 | err = chip->direction_input(chip, offset); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2003 | if (!err) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2004 | clear_bit(FLAG_IS_OUT, &desc->flags); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2005 | } else { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2006 | err = chip->direction_output(chip, offset, 0); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2007 | if (!err) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2008 | set_bit(FLAG_IS_OUT, &desc->flags); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2009 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2010 | trace_gpio_direction(desc_to_gpio(desc), value, err); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2011 | if (err < 0) |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 2012 | gpiod_err(desc, |
| 2013 | "%s: Error in set_value for open drain err %d\n", |
| 2014 | __func__, err); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2015 | } |
| 2016 | |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2017 | /* |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2018 | * _gpio_set_open_source_value() - Set the open source gpio's value. |
| 2019 | * @desc: gpio descriptor whose state need to be set. |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2020 | * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
| 2021 | */ |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2022 | static void _gpio_set_open_source_value(struct gpio_desc *desc, int value) |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2023 | { |
| 2024 | int err = 0; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2025 | struct gpio_chip *chip = desc->chip; |
| 2026 | int offset = gpio_chip_hwgpio(desc); |
| 2027 | |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2028 | if (value) { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2029 | err = chip->direction_output(chip, offset, 1); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2030 | if (!err) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2031 | set_bit(FLAG_IS_OUT, &desc->flags); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2032 | } else { |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2033 | err = chip->direction_input(chip, offset); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2034 | if (!err) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2035 | clear_bit(FLAG_IS_OUT, &desc->flags); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2036 | } |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2037 | trace_gpio_direction(desc_to_gpio(desc), !value, err); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2038 | if (err < 0) |
Mark Brown | 6424de5 | 2013-09-09 10:33:49 +0100 | [diff] [blame] | 2039 | gpiod_err(desc, |
| 2040 | "%s: Error in set_value for open source err %d\n", |
| 2041 | __func__, err); |
Laxman Dewangan | 25553ff | 2012-02-17 20:26:22 +0530 | [diff] [blame] | 2042 | } |
| 2043 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2044 | static void _gpiod_set_raw_value(struct gpio_desc *desc, int value) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2045 | { |
| 2046 | struct gpio_chip *chip; |
| 2047 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2048 | chip = desc->chip; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2049 | trace_gpio_value(desc_to_gpio(desc), 0, value); |
| 2050 | if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) |
| 2051 | _gpio_set_open_drain_value(desc, value); |
| 2052 | else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) |
| 2053 | _gpio_set_open_source_value(desc, value); |
Laxman Dewangan | aca5ce1 | 2012-02-17 20:26:21 +0530 | [diff] [blame] | 2054 | else |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2055 | chip->set(chip, gpio_chip_hwgpio(desc), value); |
| 2056 | } |
| 2057 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2058 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2059 | * gpiod_set_raw_value() - assign a gpio's raw value |
| 2060 | * @desc: gpio whose value will be assigned |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2061 | * @value: value to assign |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2062 | * |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2063 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
| 2064 | * regard for its ACTIVE_LOW status. |
| 2065 | * |
| 2066 | * This function should be called from contexts where we cannot sleep, and will |
| 2067 | * complain if the GPIO chip functions potentially sleep. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2068 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2069 | void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2070 | { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2071 | if (!desc) |
| 2072 | return; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2073 | /* Should be using gpio_set_value_cansleep() */ |
Alexandre Courbot | d8e0ac0 | 2013-09-04 20:29:25 +0900 | [diff] [blame] | 2074 | WARN_ON(desc->chip->can_sleep); |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2075 | _gpiod_set_raw_value(desc, value); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2076 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2077 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2078 | |
| 2079 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2080 | * gpiod_set_value() - assign a gpio's value |
| 2081 | * @desc: gpio whose value will be assigned |
| 2082 | * @value: value to assign |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2083 | * |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2084 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into |
| 2085 | * account |
| 2086 | * |
| 2087 | * This function should be called from contexts where we cannot sleep, and will |
| 2088 | * complain if the GPIO chip functions potentially sleep. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2089 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2090 | void gpiod_set_value(struct gpio_desc *desc, int value) |
| 2091 | { |
| 2092 | if (!desc) |
| 2093 | return; |
| 2094 | /* Should be using gpio_set_value_cansleep() */ |
| 2095 | WARN_ON(desc->chip->can_sleep); |
| 2096 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| 2097 | value = !value; |
| 2098 | _gpiod_set_raw_value(desc, value); |
| 2099 | } |
| 2100 | EXPORT_SYMBOL_GPL(gpiod_set_value); |
| 2101 | |
| 2102 | /** |
| 2103 | * gpiod_cansleep() - report whether gpio value access may sleep |
| 2104 | * @desc: gpio to check |
| 2105 | * |
| 2106 | */ |
| 2107 | int gpiod_cansleep(const struct gpio_desc *desc) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2108 | { |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 2109 | if (!desc) |
| 2110 | return 0; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2111 | return desc->chip->can_sleep; |
| 2112 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2113 | EXPORT_SYMBOL_GPL(gpiod_cansleep); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2114 | |
David Brownell | 0f6d504 | 2008-10-15 22:03:14 -0700 | [diff] [blame] | 2115 | /** |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2116 | * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
| 2117 | * @desc: gpio whose IRQ will be returned (already requested) |
David Brownell | 0f6d504 | 2008-10-15 22:03:14 -0700 | [diff] [blame] | 2118 | * |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2119 | * Return the IRQ corresponding to the passed GPIO, or an error code in case of |
| 2120 | * error. |
David Brownell | 0f6d504 | 2008-10-15 22:03:14 -0700 | [diff] [blame] | 2121 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2122 | int gpiod_to_irq(const struct gpio_desc *desc) |
David Brownell | 0f6d504 | 2008-10-15 22:03:14 -0700 | [diff] [blame] | 2123 | { |
| 2124 | struct gpio_chip *chip; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2125 | int offset; |
David Brownell | 0f6d504 | 2008-10-15 22:03:14 -0700 | [diff] [blame] | 2126 | |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 2127 | if (!desc) |
| 2128 | return -EINVAL; |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2129 | chip = desc->chip; |
| 2130 | offset = gpio_chip_hwgpio(desc); |
| 2131 | return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; |
| 2132 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2133 | EXPORT_SYMBOL_GPL(gpiod_to_irq); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2134 | |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2135 | /** |
| 2136 | * gpiod_lock_as_irq() - lock a GPIO to be used as IRQ |
| 2137 | * @gpio: the GPIO line to lock as used for IRQ |
| 2138 | * |
| 2139 | * This is used directly by GPIO drivers that want to lock down |
| 2140 | * a certain GPIO line to be used as IRQs, for example in the |
| 2141 | * .to_irq() callback of their gpio_chip, or in the .irq_enable() |
| 2142 | * of its irq_chip implementation if the GPIO is known from that |
| 2143 | * code. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2144 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2145 | int gpiod_lock_as_irq(struct gpio_desc *desc) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2146 | { |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2147 | if (!desc) |
| 2148 | return -EINVAL; |
| 2149 | |
| 2150 | if (test_bit(FLAG_IS_OUT, &desc->flags)) { |
| 2151 | gpiod_err(desc, |
| 2152 | "%s: tried to flag a GPIO set as output for IRQ\n", |
| 2153 | __func__); |
| 2154 | return -EIO; |
| 2155 | } |
| 2156 | |
| 2157 | set_bit(FLAG_USED_AS_IRQ, &desc->flags); |
| 2158 | return 0; |
| 2159 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2160 | EXPORT_SYMBOL_GPL(gpiod_lock_as_irq); |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2161 | |
| 2162 | int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
| 2163 | { |
| 2164 | return gpiod_lock_as_irq(gpiochip_offset_to_desc(chip, offset)); |
| 2165 | } |
| 2166 | EXPORT_SYMBOL_GPL(gpio_lock_as_irq); |
| 2167 | |
| 2168 | /** |
| 2169 | * gpiod_unlock_as_irq() - unlock a GPIO used as IRQ |
| 2170 | * @gpio: the GPIO line to unlock from IRQ usage |
| 2171 | * |
| 2172 | * This is used directly by GPIO drivers that want to indicate |
| 2173 | * that a certain GPIO is no longer used exclusively for IRQ. |
| 2174 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2175 | void gpiod_unlock_as_irq(struct gpio_desc *desc) |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2176 | { |
| 2177 | if (!desc) |
| 2178 | return; |
| 2179 | |
| 2180 | clear_bit(FLAG_USED_AS_IRQ, &desc->flags); |
| 2181 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2182 | EXPORT_SYMBOL_GPL(gpiod_unlock_as_irq); |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2183 | |
| 2184 | void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) |
| 2185 | { |
| 2186 | return gpiod_unlock_as_irq(gpiochip_offset_to_desc(chip, offset)); |
| 2187 | } |
| 2188 | EXPORT_SYMBOL_GPL(gpio_unlock_as_irq); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2189 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2190 | /** |
| 2191 | * gpiod_get_raw_value_cansleep() - return a gpio's raw value |
| 2192 | * @desc: gpio whose value will be returned |
| 2193 | * |
| 2194 | * Return the GPIO's raw value, i.e. the value of the physical line disregarding |
| 2195 | * its ACTIVE_LOW status. |
| 2196 | * |
| 2197 | * This function is to be called from contexts that can sleep. |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2198 | */ |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2199 | int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2200 | { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2201 | might_sleep_if(extra_checks); |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 2202 | if (!desc) |
| 2203 | return 0; |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2204 | return _gpiod_get_raw_value(desc); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2205 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2206 | EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2207 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2208 | /** |
| 2209 | * gpiod_get_value_cansleep() - return a gpio's value |
| 2210 | * @desc: gpio whose value will be returned |
| 2211 | * |
| 2212 | * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into |
| 2213 | * account. |
| 2214 | * |
| 2215 | * This function is to be called from contexts that can sleep. |
| 2216 | */ |
| 2217 | int gpiod_get_value_cansleep(const struct gpio_desc *desc) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2218 | { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2219 | int value; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2220 | |
| 2221 | might_sleep_if(extra_checks); |
| 2222 | if (!desc) |
| 2223 | return 0; |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2224 | |
| 2225 | value = _gpiod_get_raw_value(desc); |
| 2226 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| 2227 | value = !value; |
| 2228 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2229 | return value; |
| 2230 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2231 | EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2232 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2233 | /** |
| 2234 | * gpiod_set_raw_value_cansleep() - assign a gpio's raw value |
| 2235 | * @desc: gpio whose value will be assigned |
| 2236 | * @value: value to assign |
| 2237 | * |
| 2238 | * Set the raw value of the GPIO, i.e. the value of its physical line without |
| 2239 | * regard for its ACTIVE_LOW status. |
| 2240 | * |
| 2241 | * This function is to be called from contexts that can sleep. |
| 2242 | */ |
| 2243 | void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2244 | { |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2245 | might_sleep_if(extra_checks); |
Alexandre Courbot | bcabdef | 2013-02-15 14:46:14 +0900 | [diff] [blame] | 2246 | if (!desc) |
| 2247 | return; |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2248 | _gpiod_set_raw_value(desc, value); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2249 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2250 | EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2251 | |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2252 | /** |
| 2253 | * gpiod_set_value_cansleep() - assign a gpio's value |
| 2254 | * @desc: gpio whose value will be assigned |
| 2255 | * @value: value to assign |
| 2256 | * |
| 2257 | * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into |
| 2258 | * account |
| 2259 | * |
| 2260 | * This function is to be called from contexts that can sleep. |
| 2261 | */ |
| 2262 | void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2263 | { |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2264 | might_sleep_if(extra_checks); |
| 2265 | if (!desc) |
| 2266 | return; |
| 2267 | |
| 2268 | if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| 2269 | value = !value; |
| 2270 | _gpiod_set_raw_value(desc, value); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2271 | } |
Alexandre Courbot | 79a9bec | 2013-10-17 10:21:36 -0700 | [diff] [blame] | 2272 | EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2273 | |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2274 | /** |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2275 | * gpiod_add_lookup_table() - register GPIO device consumers |
| 2276 | * @table: table of consumers to register |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2277 | */ |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2278 | void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2279 | { |
| 2280 | mutex_lock(&gpio_lookup_lock); |
| 2281 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2282 | list_add_tail(&table->list, &gpio_lookup_list); |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2283 | |
| 2284 | mutex_unlock(&gpio_lookup_lock); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2285 | } |
| 2286 | |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2287 | #ifdef CONFIG_OF |
| 2288 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2289 | unsigned int idx, |
| 2290 | enum gpio_lookup_flags *flags) |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2291 | { |
| 2292 | char prop_name[32]; /* 32 is max size of property name */ |
| 2293 | enum of_gpio_flags of_flags; |
| 2294 | struct gpio_desc *desc; |
| 2295 | |
| 2296 | if (con_id) |
| 2297 | snprintf(prop_name, 32, "%s-gpios", con_id); |
| 2298 | else |
| 2299 | snprintf(prop_name, 32, "gpios"); |
| 2300 | |
| 2301 | desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, |
| 2302 | &of_flags); |
| 2303 | |
| 2304 | if (IS_ERR(desc)) |
| 2305 | return desc; |
| 2306 | |
| 2307 | if (of_flags & OF_GPIO_ACTIVE_LOW) |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2308 | *flags |= GPIO_ACTIVE_LOW; |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2309 | |
| 2310 | return desc; |
| 2311 | } |
| 2312 | #else |
| 2313 | static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, |
Alexandre Courbot | 209e64f | 2013-11-19 10:37:29 +0900 | [diff] [blame] | 2314 | unsigned int idx, |
| 2315 | enum gpio_lookup_flags *flags) |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2316 | { |
| 2317 | return ERR_PTR(-ENODEV); |
| 2318 | } |
| 2319 | #endif |
| 2320 | |
Mika Westerberg | 81f59e9 | 2013-10-10 11:01:09 +0300 | [diff] [blame] | 2321 | static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2322 | unsigned int idx, |
| 2323 | enum gpio_lookup_flags *flags) |
Mika Westerberg | 81f59e9 | 2013-10-10 11:01:09 +0300 | [diff] [blame] | 2324 | { |
Mika Westerberg | e01f440 | 2013-10-10 11:01:10 +0300 | [diff] [blame] | 2325 | struct acpi_gpio_info info; |
| 2326 | struct gpio_desc *desc; |
| 2327 | |
| 2328 | desc = acpi_get_gpiod_by_index(dev, idx, &info); |
| 2329 | if (IS_ERR(desc)) |
| 2330 | return desc; |
| 2331 | |
| 2332 | if (info.gpioint && info.active_low) |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2333 | *flags |= GPIO_ACTIVE_LOW; |
Mika Westerberg | e01f440 | 2013-10-10 11:01:10 +0300 | [diff] [blame] | 2334 | |
| 2335 | return desc; |
Mika Westerberg | 81f59e9 | 2013-10-10 11:01:09 +0300 | [diff] [blame] | 2336 | } |
| 2337 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2338 | static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
| 2339 | { |
| 2340 | const char *dev_id = dev ? dev_name(dev) : NULL; |
| 2341 | struct gpiod_lookup_table *table; |
| 2342 | |
| 2343 | mutex_lock(&gpio_lookup_lock); |
| 2344 | |
| 2345 | list_for_each_entry(table, &gpio_lookup_list, list) { |
| 2346 | if (table->dev_id && dev_id) { |
| 2347 | /* |
| 2348 | * Valid strings on both ends, must be identical to have |
| 2349 | * a match |
| 2350 | */ |
| 2351 | if (!strcmp(table->dev_id, dev_id)) |
| 2352 | goto found; |
| 2353 | } else { |
| 2354 | /* |
| 2355 | * One of the pointers is NULL, so both must be to have |
| 2356 | * a match |
| 2357 | */ |
| 2358 | if (dev_id == table->dev_id) |
| 2359 | goto found; |
| 2360 | } |
| 2361 | } |
| 2362 | table = NULL; |
| 2363 | |
| 2364 | found: |
| 2365 | mutex_unlock(&gpio_lookup_lock); |
| 2366 | return table; |
| 2367 | } |
| 2368 | |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2369 | static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2370 | unsigned int idx, |
| 2371 | enum gpio_lookup_flags *flags) |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2372 | { |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2373 | struct gpio_desc *desc = ERR_PTR(-ENOENT); |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2374 | struct gpiod_lookup_table *table; |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2375 | struct gpiod_lookup *p; |
| 2376 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2377 | table = gpiod_find_lookup_table(dev); |
| 2378 | if (!table) |
| 2379 | return desc; |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2380 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2381 | for (p = &table->table[0]; p->chip_label; p++) { |
| 2382 | struct gpio_chip *chip; |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2383 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2384 | /* idx must always match exactly */ |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2385 | if (p->idx != idx) |
| 2386 | continue; |
| 2387 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2388 | /* If the lookup entry has a con_id, require exact match */ |
| 2389 | if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) |
| 2390 | continue; |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2391 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2392 | chip = find_chip_by_name(p->chip_label); |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2393 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2394 | if (!chip) { |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2395 | dev_err(dev, "cannot find GPIO chip %s\n", |
| 2396 | p->chip_label); |
| 2397 | return ERR_PTR(-ENODEV); |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2398 | } |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2399 | |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2400 | if (chip->ngpio <= p->chip_hwnum) { |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2401 | dev_err(dev, |
| 2402 | "requested GPIO %d is out of range [0..%d] for chip %s\n", |
| 2403 | idx, chip->ngpio, chip->label); |
| 2404 | return ERR_PTR(-EINVAL); |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2405 | } |
| 2406 | |
| 2407 | desc = gpiochip_offset_to_desc(chip, p->chip_hwnum); |
| 2408 | *flags = p->flags; |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2409 | |
| 2410 | return desc; |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2411 | } |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2412 | |
| 2413 | return desc; |
| 2414 | } |
| 2415 | |
| 2416 | /** |
| 2417 | * gpio_get - obtain a GPIO for a given GPIO function |
Alexandre Courbot | ad82478 | 2013-12-03 12:20:11 +0900 | [diff] [blame] | 2418 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2419 | * @con_id: function within the GPIO consumer |
| 2420 | * |
| 2421 | * Return the GPIO descriptor corresponding to the function con_id of device |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2422 | * dev, -ENOENT if no GPIO has been assigned to the requested function, or |
| 2423 | * another IS_ERR() code if an error occured while trying to acquire the GPIO. |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2424 | */ |
| 2425 | struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id) |
| 2426 | { |
| 2427 | return gpiod_get_index(dev, con_id, 0); |
| 2428 | } |
| 2429 | EXPORT_SYMBOL_GPL(gpiod_get); |
| 2430 | |
| 2431 | /** |
| 2432 | * gpiod_get_index - obtain a GPIO from a multi-index GPIO function |
Andy Shevchenko | fdd6a5f | 2013-12-05 11:26:26 +0200 | [diff] [blame] | 2433 | * @dev: GPIO consumer, can be NULL for system-global GPIOs |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2434 | * @con_id: function within the GPIO consumer |
| 2435 | * @idx: index of the GPIO to obtain in the consumer |
| 2436 | * |
| 2437 | * This variant of gpiod_get() allows to access GPIOs other than the first |
| 2438 | * defined one for functions that define several GPIOs. |
| 2439 | * |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2440 | * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the |
| 2441 | * requested function and/or index, or another IS_ERR() code if an error |
| 2442 | * occured while trying to acquire the GPIO. |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2443 | */ |
| 2444 | struct gpio_desc *__must_check gpiod_get_index(struct device *dev, |
| 2445 | const char *con_id, |
| 2446 | unsigned int idx) |
| 2447 | { |
Alexandre Courbot | 35c5d7f | 2013-11-23 19:34:50 +0900 | [diff] [blame] | 2448 | struct gpio_desc *desc = NULL; |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2449 | int status; |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2450 | enum gpio_lookup_flags flags = 0; |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2451 | |
| 2452 | dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); |
| 2453 | |
| 2454 | /* Using device tree? */ |
| 2455 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { |
| 2456 | dev_dbg(dev, "using device tree for GPIO lookup\n"); |
| 2457 | desc = of_find_gpio(dev, con_id, idx, &flags); |
Mika Westerberg | 81f59e9 | 2013-10-10 11:01:09 +0300 | [diff] [blame] | 2458 | } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { |
| 2459 | dev_dbg(dev, "using ACPI for GPIO lookup\n"); |
| 2460 | desc = acpi_find_gpio(dev, con_id, idx, &flags); |
Alexandre Courbot | 35c5d7f | 2013-11-23 19:34:50 +0900 | [diff] [blame] | 2461 | } |
| 2462 | |
| 2463 | /* |
| 2464 | * Either we are not using DT or ACPI, or their lookup did not return |
| 2465 | * a result. In that case, use platform lookup as a fallback. |
| 2466 | */ |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2467 | if (!desc || desc == ERR_PTR(-ENOENT)) { |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2468 | dev_dbg(dev, "using lookup tables for GPIO lookup"); |
Alexandre Courbot | 2a3cf6a | 2013-12-11 11:32:28 +0900 | [diff] [blame] | 2469 | desc = gpiod_find(dev, con_id, idx, &flags); |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2470 | } |
| 2471 | |
| 2472 | if (IS_ERR(desc)) { |
Heikki Krogerus | 351cfe0 | 2013-11-29 15:47:34 +0200 | [diff] [blame] | 2473 | dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2474 | return desc; |
| 2475 | } |
| 2476 | |
| 2477 | status = gpiod_request(desc, con_id); |
| 2478 | |
| 2479 | if (status < 0) |
| 2480 | return ERR_PTR(status); |
| 2481 | |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2482 | if (flags & GPIO_ACTIVE_LOW) |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2483 | set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
Alexandre Courbot | 53e7cac | 2013-11-16 21:44:52 +0900 | [diff] [blame] | 2484 | if (flags & GPIO_OPEN_DRAIN) |
| 2485 | set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
| 2486 | if (flags & GPIO_OPEN_SOURCE) |
| 2487 | set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
Alexandre Courbot | bae48da | 2013-10-17 10:21:38 -0700 | [diff] [blame] | 2488 | |
| 2489 | return desc; |
| 2490 | } |
| 2491 | EXPORT_SYMBOL_GPL(gpiod_get_index); |
| 2492 | |
| 2493 | /** |
| 2494 | * gpiod_put - dispose of a GPIO descriptor |
| 2495 | * @desc: GPIO descriptor to dispose of |
| 2496 | * |
| 2497 | * No descriptor can be used after gpiod_put() has been called on it. |
| 2498 | */ |
| 2499 | void gpiod_put(struct gpio_desc *desc) |
| 2500 | { |
| 2501 | gpiod_free(desc); |
| 2502 | } |
| 2503 | EXPORT_SYMBOL_GPL(gpiod_put); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2504 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2505 | #ifdef CONFIG_DEBUG_FS |
| 2506 | |
| 2507 | static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
| 2508 | { |
| 2509 | unsigned i; |
| 2510 | unsigned gpio = chip->base; |
Alexandre Courbot | 6c0b4e6 | 2013-02-03 01:29:30 +0900 | [diff] [blame] | 2511 | struct gpio_desc *gdesc = &chip->desc[0]; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2512 | int is_out; |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2513 | int is_irq; |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2514 | |
| 2515 | for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { |
| 2516 | if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) |
| 2517 | continue; |
| 2518 | |
Alexandre Courbot | 372e722 | 2013-02-03 01:29:29 +0900 | [diff] [blame] | 2519 | gpiod_get_direction(gdesc); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2520 | is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2521 | is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
| 2522 | seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2523 | gpio, gdesc->label, |
| 2524 | is_out ? "out" : "in ", |
| 2525 | chip->get |
| 2526 | ? (chip->get(chip, i) ? "hi" : "lo") |
Linus Walleij | d468bf9 | 2013-09-24 11:54:38 +0200 | [diff] [blame] | 2527 | : "? ", |
| 2528 | is_irq ? "IRQ" : " "); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2529 | seq_printf(s, "\n"); |
| 2530 | } |
| 2531 | } |
| 2532 | |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2533 | static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2534 | { |
Grant Likely | 362432a | 2013-02-09 09:41:49 +0000 | [diff] [blame] | 2535 | unsigned long flags; |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2536 | struct gpio_chip *chip = NULL; |
Alexandre Courbot | cb1650d | 2013-02-03 01:29:27 +0900 | [diff] [blame] | 2537 | loff_t index = *pos; |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2538 | |
| 2539 | s->private = ""; |
| 2540 | |
Grant Likely | 362432a | 2013-02-09 09:41:49 +0000 | [diff] [blame] | 2541 | spin_lock_irqsave(&gpio_lock, flags); |
Alexandre Courbot | cb1650d | 2013-02-03 01:29:27 +0900 | [diff] [blame] | 2542 | list_for_each_entry(chip, &gpio_chips, list) |
Grant Likely | 362432a | 2013-02-09 09:41:49 +0000 | [diff] [blame] | 2543 | if (index-- == 0) { |
| 2544 | spin_unlock_irqrestore(&gpio_lock, flags); |
Alexandre Courbot | cb1650d | 2013-02-03 01:29:27 +0900 | [diff] [blame] | 2545 | return chip; |
Grant Likely | 362432a | 2013-02-09 09:41:49 +0000 | [diff] [blame] | 2546 | } |
| 2547 | spin_unlock_irqrestore(&gpio_lock, flags); |
Alexandre Courbot | cb1650d | 2013-02-03 01:29:27 +0900 | [diff] [blame] | 2548 | |
| 2549 | return NULL; |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2550 | } |
| 2551 | |
| 2552 | static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| 2553 | { |
Grant Likely | 362432a | 2013-02-09 09:41:49 +0000 | [diff] [blame] | 2554 | unsigned long flags; |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2555 | struct gpio_chip *chip = v; |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2556 | void *ret = NULL; |
| 2557 | |
Grant Likely | 362432a | 2013-02-09 09:41:49 +0000 | [diff] [blame] | 2558 | spin_lock_irqsave(&gpio_lock, flags); |
Alexandre Courbot | cb1650d | 2013-02-03 01:29:27 +0900 | [diff] [blame] | 2559 | if (list_is_last(&chip->list, &gpio_chips)) |
| 2560 | ret = NULL; |
| 2561 | else |
| 2562 | ret = list_entry(chip->list.next, struct gpio_chip, list); |
Grant Likely | 362432a | 2013-02-09 09:41:49 +0000 | [diff] [blame] | 2563 | spin_unlock_irqrestore(&gpio_lock, flags); |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2564 | |
| 2565 | s->private = "\n"; |
| 2566 | ++*pos; |
| 2567 | |
| 2568 | return ret; |
| 2569 | } |
| 2570 | |
| 2571 | static void gpiolib_seq_stop(struct seq_file *s, void *v) |
| 2572 | { |
| 2573 | } |
| 2574 | |
| 2575 | static int gpiolib_seq_show(struct seq_file *s, void *v) |
| 2576 | { |
| 2577 | struct gpio_chip *chip = v; |
| 2578 | struct device *dev; |
| 2579 | |
| 2580 | seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, |
| 2581 | chip->base, chip->base + chip->ngpio - 1); |
| 2582 | dev = chip->dev; |
| 2583 | if (dev) |
| 2584 | seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", |
| 2585 | dev_name(dev)); |
| 2586 | if (chip->label) |
| 2587 | seq_printf(s, ", %s", chip->label); |
| 2588 | if (chip->can_sleep) |
| 2589 | seq_printf(s, ", can sleep"); |
| 2590 | seq_printf(s, ":\n"); |
| 2591 | |
| 2592 | if (chip->dbg_show) |
| 2593 | chip->dbg_show(s, chip); |
| 2594 | else |
| 2595 | gpiolib_dbg_show(s, chip); |
| 2596 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2597 | return 0; |
| 2598 | } |
| 2599 | |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2600 | static const struct seq_operations gpiolib_seq_ops = { |
| 2601 | .start = gpiolib_seq_start, |
| 2602 | .next = gpiolib_seq_next, |
| 2603 | .stop = gpiolib_seq_stop, |
| 2604 | .show = gpiolib_seq_show, |
| 2605 | }; |
| 2606 | |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2607 | static int gpiolib_open(struct inode *inode, struct file *file) |
| 2608 | { |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2609 | return seq_open(file, &gpiolib_seq_ops); |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2610 | } |
| 2611 | |
Alexey Dobriyan | 828c095 | 2009-10-01 15:43:56 -0700 | [diff] [blame] | 2612 | static const struct file_operations gpiolib_operations = { |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2613 | .owner = THIS_MODULE, |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2614 | .open = gpiolib_open, |
| 2615 | .read = seq_read, |
| 2616 | .llseek = seq_lseek, |
Thierry Reding | f9c4a31 | 2012-04-12 13:26:01 +0200 | [diff] [blame] | 2617 | .release = seq_release, |
David Brownell | d2876d0 | 2008-02-04 22:28:20 -0800 | [diff] [blame] | 2618 | }; |
| 2619 | |
| 2620 | static int __init gpiolib_debugfs_init(void) |
| 2621 | { |
| 2622 | /* /sys/kernel/debug/gpio */ |
| 2623 | (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, |
| 2624 | NULL, NULL, &gpiolib_operations); |
| 2625 | return 0; |
| 2626 | } |
| 2627 | subsys_initcall(gpiolib_debugfs_init); |
| 2628 | |
| 2629 | #endif /* DEBUG_FS */ |