| // SPDX-License-Identifier: GPL-2.0+ |
| // |
| // Driver for Panasonic AN30259A 3-channel LED driver |
| // |
| // Copyright (c) 2018 Simon Shields <simon@lineageos.org> |
| // |
| // Datasheet: |
| // https://www.alliedelec.com/m/d/a9d2b3ee87c2d1a535a41dd747b1c247.pdf |
| |
| #include <linux/i2c.h> |
| #include <linux/leds.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/of.h> |
| #include <linux/regmap.h> |
| |
| #define AN30259A_MAX_LEDS 3 |
| |
| #define AN30259A_REG_SRESET 0x00 |
| #define AN30259A_LED_SRESET BIT(0) |
| |
| /* LED power registers */ |
| #define AN30259A_REG_LED_ON 0x01 |
| #define AN30259A_LED_EN(x) BIT((x) - 1) |
| #define AN30259A_LED_SLOPE(x) BIT(((x) - 1) + 4) |
| |
| #define AN30259A_REG_LEDCC(x) (0x03 + ((x) - 1)) |
| |
| /* slope control registers */ |
| #define AN30259A_REG_SLOPE(x) (0x06 + ((x) - 1)) |
| #define AN30259A_LED_SLOPETIME1(x) (x) |
| #define AN30259A_LED_SLOPETIME2(x) ((x) << 4) |
| |
| #define AN30259A_REG_LEDCNT1(x) (0x09 + (4 * ((x) - 1))) |
| #define AN30259A_LED_DUTYMAX(x) ((x) << 4) |
| #define AN30259A_LED_DUTYMID(x) (x) |
| |
| #define AN30259A_REG_LEDCNT2(x) (0x0A + (4 * ((x) - 1))) |
| #define AN30259A_LED_DELAY(x) ((x) << 4) |
| #define AN30259A_LED_DUTYMIN(x) (x) |
| |
| /* detention time control (length of each slope step) */ |
| #define AN30259A_REG_LEDCNT3(x) (0x0B + (4 * ((x) - 1))) |
| #define AN30259A_LED_DT1(x) (x) |
| #define AN30259A_LED_DT2(x) ((x) << 4) |
| |
| #define AN30259A_REG_LEDCNT4(x) (0x0C + (4 * ((x) - 1))) |
| #define AN30259A_LED_DT3(x) (x) |
| #define AN30259A_LED_DT4(x) ((x) << 4) |
| |
| #define AN30259A_REG_MAX 0x14 |
| |
| #define AN30259A_BLINK_MAX_TIME 7500 /* ms */ |
| #define AN30259A_SLOPE_RESOLUTION 500 /* ms */ |
| |
| #define AN30259A_NAME "an30259a" |
| |
| struct an30259a; |
| |
| struct an30259a_led { |
| struct an30259a *chip; |
| struct fwnode_handle *fwnode; |
| struct led_classdev cdev; |
| u32 num; |
| enum led_default_state default_state; |
| bool sloping; |
| }; |
| |
| struct an30259a { |
| struct mutex mutex; /* held when writing to registers */ |
| struct i2c_client *client; |
| struct an30259a_led leds[AN30259A_MAX_LEDS]; |
| struct regmap *regmap; |
| int num_leds; |
| }; |
| |
| static int an30259a_brightness_set(struct led_classdev *cdev, |
| enum led_brightness brightness) |
| { |
| struct an30259a_led *led; |
| int ret; |
| unsigned int led_on; |
| |
| led = container_of(cdev, struct an30259a_led, cdev); |
| mutex_lock(&led->chip->mutex); |
| |
| ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on); |
| if (ret) |
| goto error; |
| |
| switch (brightness) { |
| case LED_OFF: |
| led_on &= ~AN30259A_LED_EN(led->num); |
| led_on &= ~AN30259A_LED_SLOPE(led->num); |
| led->sloping = false; |
| break; |
| default: |
| led_on |= AN30259A_LED_EN(led->num); |
| if (led->sloping) |
| led_on |= AN30259A_LED_SLOPE(led->num); |
| ret = regmap_write(led->chip->regmap, |
| AN30259A_REG_LEDCNT1(led->num), |
| AN30259A_LED_DUTYMAX(0xf) | |
| AN30259A_LED_DUTYMID(0xf)); |
| if (ret) |
| goto error; |
| break; |
| } |
| |
| ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on); |
| if (ret) |
| goto error; |
| |
| ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCC(led->num), |
| brightness); |
| |
| error: |
| mutex_unlock(&led->chip->mutex); |
| |
| return ret; |
| } |
| |
| static int an30259a_blink_set(struct led_classdev *cdev, |
| unsigned long *delay_off, unsigned long *delay_on) |
| { |
| struct an30259a_led *led; |
| int ret, num; |
| unsigned int led_on; |
| unsigned long off = *delay_off, on = *delay_on; |
| |
| led = container_of(cdev, struct an30259a_led, cdev); |
| |
| mutex_lock(&led->chip->mutex); |
| num = led->num; |
| |
| /* slope time can only be a multiple of 500ms. */ |
| if (off % AN30259A_SLOPE_RESOLUTION || on % AN30259A_SLOPE_RESOLUTION) { |
| ret = -EINVAL; |
| goto error; |
| } |
| |
| /* up to a maximum of 7500ms. */ |
| if (off > AN30259A_BLINK_MAX_TIME || on > AN30259A_BLINK_MAX_TIME) { |
| ret = -EINVAL; |
| goto error; |
| } |
| |
| /* if no blink specified, default to 1 Hz. */ |
| if (!off && !on) { |
| *delay_off = off = 500; |
| *delay_on = on = 500; |
| } |
| |
| /* convert into values the HW will understand. */ |
| off /= AN30259A_SLOPE_RESOLUTION; |
| on /= AN30259A_SLOPE_RESOLUTION; |
| |
| /* duty min should be zero (=off), delay should be zero. */ |
| ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT2(num), |
| AN30259A_LED_DELAY(0) | AN30259A_LED_DUTYMIN(0)); |
| if (ret) |
| goto error; |
| |
| /* reset detention time (no "breathing" effect). */ |
| ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT3(num), |
| AN30259A_LED_DT1(0) | AN30259A_LED_DT2(0)); |
| if (ret) |
| goto error; |
| ret = regmap_write(led->chip->regmap, AN30259A_REG_LEDCNT4(num), |
| AN30259A_LED_DT3(0) | AN30259A_LED_DT4(0)); |
| if (ret) |
| goto error; |
| |
| /* slope time controls on/off cycle length. */ |
| ret = regmap_write(led->chip->regmap, AN30259A_REG_SLOPE(num), |
| AN30259A_LED_SLOPETIME1(off) | |
| AN30259A_LED_SLOPETIME2(on)); |
| if (ret) |
| goto error; |
| |
| /* Finally, enable slope mode. */ |
| ret = regmap_read(led->chip->regmap, AN30259A_REG_LED_ON, &led_on); |
| if (ret) |
| goto error; |
| |
| led_on |= AN30259A_LED_SLOPE(num) | AN30259A_LED_EN(led->num); |
| |
| ret = regmap_write(led->chip->regmap, AN30259A_REG_LED_ON, led_on); |
| |
| if (!ret) |
| led->sloping = true; |
| error: |
| mutex_unlock(&led->chip->mutex); |
| |
| return ret; |
| } |
| |
| static int an30259a_dt_init(struct i2c_client *client, |
| struct an30259a *chip) |
| { |
| struct device_node *np = dev_of_node(&client->dev), *child; |
| int count, ret; |
| int i = 0; |
| struct an30259a_led *led; |
| |
| count = of_get_available_child_count(np); |
| if (!count || count > AN30259A_MAX_LEDS) |
| return -EINVAL; |
| |
| for_each_available_child_of_node(np, child) { |
| u32 source; |
| |
| ret = of_property_read_u32(child, "reg", &source); |
| if (ret != 0 || !source || source > AN30259A_MAX_LEDS) { |
| dev_err(&client->dev, "Couldn't read LED address: %d\n", |
| ret); |
| count--; |
| continue; |
| } |
| |
| led = &chip->leds[i]; |
| |
| led->num = source; |
| led->chip = chip; |
| led->fwnode = of_fwnode_handle(child); |
| led->default_state = led_init_default_state_get(led->fwnode); |
| |
| i++; |
| } |
| |
| if (!count) |
| return -EINVAL; |
| |
| chip->num_leds = i; |
| |
| return 0; |
| } |
| |
| static const struct regmap_config an30259a_regmap_config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| .max_register = AN30259A_REG_MAX, |
| }; |
| |
| static void an30259a_init_default_state(struct an30259a_led *led) |
| { |
| struct an30259a *chip = led->chip; |
| int led_on, err; |
| |
| switch (led->default_state) { |
| case LEDS_DEFSTATE_ON: |
| led->cdev.brightness = LED_FULL; |
| break; |
| case LEDS_DEFSTATE_KEEP: |
| err = regmap_read(chip->regmap, AN30259A_REG_LED_ON, &led_on); |
| if (err) |
| break; |
| |
| if (!(led_on & AN30259A_LED_EN(led->num))) { |
| led->cdev.brightness = LED_OFF; |
| break; |
| } |
| regmap_read(chip->regmap, AN30259A_REG_LEDCC(led->num), |
| &led->cdev.brightness); |
| break; |
| default: |
| led->cdev.brightness = LED_OFF; |
| } |
| |
| an30259a_brightness_set(&led->cdev, led->cdev.brightness); |
| } |
| |
| static int an30259a_probe(struct i2c_client *client) |
| { |
| struct an30259a *chip; |
| int i, err; |
| |
| chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); |
| if (!chip) |
| return -ENOMEM; |
| |
| err = an30259a_dt_init(client, chip); |
| if (err < 0) |
| return err; |
| |
| mutex_init(&chip->mutex); |
| chip->client = client; |
| i2c_set_clientdata(client, chip); |
| |
| chip->regmap = devm_regmap_init_i2c(client, &an30259a_regmap_config); |
| |
| if (IS_ERR(chip->regmap)) { |
| err = PTR_ERR(chip->regmap); |
| dev_err(&client->dev, "Failed to allocate register map: %d\n", |
| err); |
| goto exit; |
| } |
| |
| for (i = 0; i < chip->num_leds; i++) { |
| struct led_init_data init_data = {}; |
| |
| an30259a_init_default_state(&chip->leds[i]); |
| chip->leds[i].cdev.brightness_set_blocking = |
| an30259a_brightness_set; |
| chip->leds[i].cdev.blink_set = an30259a_blink_set; |
| |
| init_data.fwnode = chip->leds[i].fwnode; |
| init_data.devicename = AN30259A_NAME; |
| init_data.default_label = ":"; |
| |
| err = devm_led_classdev_register_ext(&client->dev, |
| &chip->leds[i].cdev, |
| &init_data); |
| if (err < 0) |
| goto exit; |
| } |
| return 0; |
| |
| exit: |
| mutex_destroy(&chip->mutex); |
| return err; |
| } |
| |
| static void an30259a_remove(struct i2c_client *client) |
| { |
| struct an30259a *chip = i2c_get_clientdata(client); |
| |
| mutex_destroy(&chip->mutex); |
| } |
| |
| static const struct of_device_id an30259a_match_table[] = { |
| { .compatible = "panasonic,an30259a", }, |
| { /* sentinel */ }, |
| }; |
| |
| MODULE_DEVICE_TABLE(of, an30259a_match_table); |
| |
| static const struct i2c_device_id an30259a_id[] = { |
| { "an30259a", 0 }, |
| { /* sentinel */ }, |
| }; |
| MODULE_DEVICE_TABLE(i2c, an30259a_id); |
| |
| static struct i2c_driver an30259a_driver = { |
| .driver = { |
| .name = "leds-an30259a", |
| .of_match_table = of_match_ptr(an30259a_match_table), |
| }, |
| .probe_new = an30259a_probe, |
| .remove = an30259a_remove, |
| .id_table = an30259a_id, |
| }; |
| |
| module_i2c_driver(an30259a_driver); |
| |
| MODULE_AUTHOR("Simon Shields <simon@lineageos.org>"); |
| MODULE_DESCRIPTION("AN30259A LED driver"); |
| MODULE_LICENSE("GPL v2"); |