[PATCH v5 07/12] leds: leds-gpio: Add support for GPIO descriptors

Rafael J. Wysocki
2014-10-17T12:11:27Z

From: Mika Westerberg <mika.westerberg@linux.intel.com>

GPIO descriptors are the preferred way over legacy GPIO numbers
nowadays. Convert the driver to use GPIO descriptors internally but
still allow passing legacy GPIO numbers from platform data to support
existing platforms.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Bryan Wu <cooloney@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/leds/leds-gpio.c | 80 ++++++++++++++++++++++++++---------------------
include/linux/leds.h | 1
2 files changed, 46 insertions(+), 35 deletions(-)

Index: linux-pm/drivers/leds/leds-gpio.c
===================================================================
--- linux-pm.orig/drivers/leds/leds-gpio.c
+++ linux-pm/drivers/leds/leds-gpio.c
@@ -13,6 +13,7 @@
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/leds.h>
#include <linux/of.h>
#include <linux/of_platform.h>
@@ -24,11 +25,10 @@

struct gpio_led_data {
struct led_classdev cdev;
- unsigned gpio;
+ struct gpio_desc *gpiod;
struct work_struct work;
u8 new_level;
u8 can_sleep;
- u8 active_low;
u8 blinking;
int (*platform_gpio_blink_set)(unsigned gpio, int state,
unsigned long *delay_on, unsigned long *delay_off);
@@ -40,12 +40,16 @@ static void gpio_led_work(struct work_st
container_of(work, struct gpio_led_data, work);

if (led_dat->blinking) {
- led_dat->platform_gpio_blink_set(led_dat->gpio,
- led_dat->new_level,
- NULL, NULL);
+ int gpio = desc_to_gpio(led_dat->gpiod);
+ int level = led_dat->new_level;
+
+ if (gpiod_is_active_low(led_dat->gpiod))
+ level = !level;
+
+ led_dat->platform_gpio_blink_set(gpio, level, NULL, NULL);
led_dat->blinking = 0;
} else
- gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level);
+ gpiod_set_value_cansleep(led_dat->gpiod, led_dat->new_level);
}

static void gpio_led_set(struct led_classdev *led_cdev,
@@ -60,9 +64,6 @@ static void gpio_led_set(struct led_clas
else
level = 1;

- if (led_dat->active_low)
- level = !level;
-
/* Setting GPIOs with I2C/etc requires a task context, and we don't
* seem to have a reliable way to know if we're already in one; so
* let's just assume the worst.
@@ -72,11 +73,16 @@ static void gpio_led_set(struct led_clas
schedule_work(&led_dat->work);
} else {
if (led_dat->blinking) {
- led_dat->platform_gpio_blink_set(led_dat->gpio, level,
- NULL, NULL);
+ int gpio = desc_to_gpio(led_dat->gpiod);
+
+ if (gpiod_is_active_low(led_dat->gpiod))
+ level = !level;
+
+ led_dat->platform_gpio_blink_set(gpio, level, NULL,
+ NULL);
led_dat->blinking = 0;
} else
- gpio_set_value(led_dat->gpio, level);
+ gpiod_set_value(led_dat->gpiod, level);
}
}

@@ -85,9 +91,10 @@ static int gpio_blink_set(struct led_cla
{
struct gpio_led_data *led_dat =
container_of(led_cdev, struct gpio_led_data, cdev);
+ int gpio = desc_to_gpio(led_dat->gpiod);

led_dat->blinking = 1;
- return led_dat->platform_gpio_blink_set(led_dat->gpio, GPIO_LED_BLINK,
+ return led_dat->platform_gpio_blink_set(gpio, GPIO_LED_BLINK,
delay_on, delay_off);
}

@@ -97,24 +104,33 @@ static int create_gpio_led(const struct
{
int ret, state;

- led_dat->gpio = -1;
+ if (!template->gpiod) {
+ unsigned long flags = 0;

- /* skip leds that aren't available */
- if (!gpio_is_valid(template->gpio)) {
- dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n",
- template->gpio, template->name);
- return 0;
+ /* skip leds that aren't available */
+ if (!gpio_is_valid(template->gpio)) {
+ dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n",
+ template->gpio, template->name);
+ return 0;
+ }
+
+ if (template->active_low)
+ flags |= GPIOF_ACTIVE_LOW;
+
+ ret = devm_gpio_request_one(parent, template->gpio, flags,
+ template->name);
+ if (ret < 0)
+ return ret;
+
+ led_dat->gpiod = gpio_to_desc(template->gpio);
+ if (IS_ERR(led_dat->gpiod))
+ return PTR_ERR(led_dat->gpiod);
}

- ret = devm_gpio_request(parent, template->gpio, template->name);
- if (ret < 0)
- return ret;
-
led_dat->cdev.name = template->name;
led_dat->cdev.default_trigger = template->default_trigger;
- led_dat->gpio = template->gpio;
- led_dat->can_sleep = gpio_cansleep(template->gpio);
- led_dat->active_low = template->active_low;
+ led_dat->gpiod = template->gpiod;
+ led_dat->can_sleep = gpiod_cansleep(template->gpiod);
led_dat->blinking = 0;
if (blink_set) {
led_dat->platform_gpio_blink_set = blink_set;
@@ -122,30 +138,24 @@ static int create_gpio_led(const struct
}
led_dat->cdev.brightness_set = gpio_led_set;
if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)
- state = !!gpio_get_value_cansleep(led_dat->gpio) ^ led_dat->active_low;
+ state = !!gpiod_get_value_cansleep(led_dat->gpiod);
else
state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
if (!template->retain_state_suspended)
led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;

- ret = gpio_direction_output(led_dat->gpio, led_dat->active_low ^ state);
+ ret = gpiod_direction_output(led_dat->gpiod, state);
if (ret < 0)
return ret;

INIT_WORK(&led_dat->work, gpio_led_work);

- ret = led_classdev_register(parent, &led_dat->cdev);
- if (ret < 0)
- return ret;
-
- return 0;
+ return led_classdev_register(parent, &led_dat->cdev);
}

static void delete_gpio_led(struct gpio_led_data *led)
{
- if (!gpio_is_valid(led->gpio))
- return;
led_classdev_unregister(&led->cdev);
cancel_work_sync(&led->work);
}
Index: linux-pm/include/linux/leds.h
===================================================================
--- linux-pm.orig/include/linux/leds.h
+++ linux-pm/include/linux/leds.h
@@ -251,6 +251,7 @@ struct gpio_led {
unsigned retain_state_suspended : 1;
unsigned default_state : 2;
/* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
+ struct gpio_desc *gpiod;
};
#define LEDS_GPIO_DEFSTATE_OFF 0
#define LEDS_GPIO_DEFSTATE_ON 1