ssb: add GPIO driver
Register a GPIO driver to access the GPIOs provided by the chip.
The GPIOs of the SoC should always start at 0 and the other GPIOs could
start at a random position. There is just one SoC in a system and when
they start at 0 the number is predictable.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Patchwork: http://patchwork.linux-mips.org/patch/4591
Acked-by: Florian Fainelli <florian@openwrt.org>
diff --git a/drivers/ssb/Kconfig b/drivers/ssb/Kconfig
index 42cdaa9..ff3c8a2 100644
--- a/drivers/ssb/Kconfig
+++ b/drivers/ssb/Kconfig
@@ -160,4 +160,13 @@
If unsure, say N
+config SSB_DRIVER_GPIO
+ bool "SSB GPIO driver"
+ depends on SSB
+ select GPIOLIB
+ help
+ Driver to provide access to the GPIO pins on the bus.
+
+ If unsure, say N
+
endmenu
diff --git a/drivers/ssb/Makefile b/drivers/ssb/Makefile
index 656e58b..9159ba7 100644
--- a/drivers/ssb/Makefile
+++ b/drivers/ssb/Makefile
@@ -15,6 +15,7 @@
ssb-$(CONFIG_SSB_DRIVER_EXTIF) += driver_extif.o
ssb-$(CONFIG_SSB_DRIVER_PCICORE) += driver_pcicore.o
ssb-$(CONFIG_SSB_DRIVER_GIGE) += driver_gige.o
+ssb-$(CONFIG_SSB_DRIVER_GPIO) += driver_gpio.o
# b43 pci-ssb-bridge driver
# Not strictly a part of SSB, but kept here for convenience
diff --git a/drivers/ssb/driver_gpio.c b/drivers/ssb/driver_gpio.c
new file mode 100644
index 0000000..97ac0a3
--- /dev/null
+++ b/drivers/ssb/driver_gpio.c
@@ -0,0 +1,176 @@
+/*
+ * Sonics Silicon Backplane
+ * GPIO driver
+ *
+ * Copyright 2011, Broadcom Corporation
+ * Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de>
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include <linux/gpio.h>
+#include <linux/export.h>
+#include <linux/ssb/ssb.h>
+
+#include "ssb_private.h"
+
+static struct ssb_bus *ssb_gpio_get_bus(struct gpio_chip *chip)
+{
+ return container_of(chip, struct ssb_bus, gpio);
+}
+
+static int ssb_gpio_chipco_get_value(struct gpio_chip *chip, unsigned gpio)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ return !!ssb_chipco_gpio_in(&bus->chipco, 1 << gpio);
+}
+
+static void ssb_gpio_chipco_set_value(struct gpio_chip *chip, unsigned gpio,
+ int value)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ ssb_chipco_gpio_out(&bus->chipco, 1 << gpio, value ? 1 << gpio : 0);
+}
+
+static int ssb_gpio_chipco_direction_input(struct gpio_chip *chip,
+ unsigned gpio)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ ssb_chipco_gpio_outen(&bus->chipco, 1 << gpio, 0);
+ return 0;
+}
+
+static int ssb_gpio_chipco_direction_output(struct gpio_chip *chip,
+ unsigned gpio, int value)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ ssb_chipco_gpio_outen(&bus->chipco, 1 << gpio, 1 << gpio);
+ ssb_chipco_gpio_out(&bus->chipco, 1 << gpio, value ? 1 << gpio : 0);
+ return 0;
+}
+
+static int ssb_gpio_chipco_request(struct gpio_chip *chip, unsigned gpio)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ ssb_chipco_gpio_control(&bus->chipco, 1 << gpio, 0);
+ /* clear pulldown */
+ ssb_chipco_gpio_pulldown(&bus->chipco, 1 << gpio, 0);
+ /* Set pullup */
+ ssb_chipco_gpio_pullup(&bus->chipco, 1 << gpio, 1 << gpio);
+
+ return 0;
+}
+
+static void ssb_gpio_chipco_free(struct gpio_chip *chip, unsigned gpio)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ /* clear pullup */
+ ssb_chipco_gpio_pullup(&bus->chipco, 1 << gpio, 0);
+}
+
+static int ssb_gpio_chipco_init(struct ssb_bus *bus)
+{
+ struct gpio_chip *chip = &bus->gpio;
+
+ chip->label = "ssb_chipco_gpio";
+ chip->owner = THIS_MODULE;
+ chip->request = ssb_gpio_chipco_request;
+ chip->free = ssb_gpio_chipco_free;
+ chip->get = ssb_gpio_chipco_get_value;
+ chip->set = ssb_gpio_chipco_set_value;
+ chip->direction_input = ssb_gpio_chipco_direction_input;
+ chip->direction_output = ssb_gpio_chipco_direction_output;
+ chip->ngpio = 16;
+ /* There is just one SoC in one device and its GPIO addresses should be
+ * deterministic to address them more easily. The other buses could get
+ * a random base number. */
+ if (bus->bustype == SSB_BUSTYPE_SSB)
+ chip->base = 0;
+ else
+ chip->base = -1;
+
+ return gpiochip_add(chip);
+}
+
+#ifdef CONFIG_SSB_DRIVER_EXTIF
+
+static int ssb_gpio_extif_get_value(struct gpio_chip *chip, unsigned gpio)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ return !!ssb_extif_gpio_in(&bus->extif, 1 << gpio);
+}
+
+static void ssb_gpio_extif_set_value(struct gpio_chip *chip, unsigned gpio,
+ int value)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ ssb_extif_gpio_out(&bus->extif, 1 << gpio, value ? 1 << gpio : 0);
+}
+
+static int ssb_gpio_extif_direction_input(struct gpio_chip *chip,
+ unsigned gpio)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ ssb_extif_gpio_outen(&bus->extif, 1 << gpio, 0);
+ return 0;
+}
+
+static int ssb_gpio_extif_direction_output(struct gpio_chip *chip,
+ unsigned gpio, int value)
+{
+ struct ssb_bus *bus = ssb_gpio_get_bus(chip);
+
+ ssb_extif_gpio_outen(&bus->extif, 1 << gpio, 1 << gpio);
+ ssb_extif_gpio_out(&bus->extif, 1 << gpio, value ? 1 << gpio : 0);
+ return 0;
+}
+
+static int ssb_gpio_extif_init(struct ssb_bus *bus)
+{
+ struct gpio_chip *chip = &bus->gpio;
+
+ chip->label = "ssb_extif_gpio";
+ chip->owner = THIS_MODULE;
+ chip->get = ssb_gpio_extif_get_value;
+ chip->set = ssb_gpio_extif_set_value;
+ chip->direction_input = ssb_gpio_extif_direction_input;
+ chip->direction_output = ssb_gpio_extif_direction_output;
+ chip->ngpio = 5;
+ /* There is just one SoC in one device and its GPIO addresses should be
+ * deterministic to address them more easily. The other buses could get
+ * a random base number. */
+ if (bus->bustype == SSB_BUSTYPE_SSB)
+ chip->base = 0;
+ else
+ chip->base = -1;
+
+ return gpiochip_add(chip);
+}
+
+#else
+static int ssb_gpio_extif_init(struct ssb_bus *bus)
+{
+ return -ENOTSUPP;
+}
+#endif
+
+int ssb_gpio_init(struct ssb_bus *bus)
+{
+ if (ssb_chipco_available(&bus->chipco))
+ return ssb_gpio_chipco_init(bus);
+ else if (ssb_extif_available(&bus->extif))
+ return ssb_gpio_extif_init(bus);
+ else
+ SSB_WARN_ON(1);
+
+ return -1;
+}
diff --git a/drivers/ssb/main.c b/drivers/ssb/main.c
index 6fe2d10..87f0ddf 100644
--- a/drivers/ssb/main.c
+++ b/drivers/ssb/main.c
@@ -798,6 +798,12 @@
ssb_chipcommon_init(&bus->chipco);
ssb_extif_init(&bus->extif);
ssb_mipscore_init(&bus->mipscore);
+ err = ssb_gpio_init(bus);
+ if (err == -ENOTSUPP)
+ ssb_dprintk(KERN_DEBUG PFX "GPIO driver not activated\n");
+ else if (err)
+ ssb_dprintk(KERN_ERR PFX
+ "Error registering GPIO driver: %i\n", err);
err = ssb_fetch_invariants(bus, get_invariants);
if (err) {
ssb_bus_may_powerdown(bus);
diff --git a/drivers/ssb/ssb_private.h b/drivers/ssb/ssb_private.h
index d6a1ba9..463b76a2 100644
--- a/drivers/ssb/ssb_private.h
+++ b/drivers/ssb/ssb_private.h
@@ -219,4 +219,13 @@
}
#endif
+#ifdef CONFIG_SSB_DRIVER_GPIO
+extern int ssb_gpio_init(struct ssb_bus *bus);
+#else /* CONFIG_SSB_DRIVER_GPIO */
+static inline int ssb_gpio_init(struct ssb_bus *bus)
+{
+ return -ENOTSUPP;
+}
+#endif /* CONFIG_SSB_DRIVER_GPIO */
+
#endif /* LINUX_SSB_PRIVATE_H_ */
