[PATCH v3 08/15] leds: leds-gpio: Add support for GPIO descriptors

From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: linux-kernel@vger.kernel.org
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>,
	linux-acpi@vger.kernel.org, devicetree@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Linus Walleij <linus.walleij@linaro.org>,
	Alexandre Courbot <gnurou@gmail.com>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	Bryan Wu <cooloney@gmail.com>, Lee Jones <lee.jones@linaro.org>,
	Grant Likely <grant.likely@linaro.org>,
	Arnd Bergmann <arnd@arndb.de>, Aaron Lu <aaron.lu@intel.com>,
	Darren Hart <dvhart@linux.intel.com>
Subject: [PATCH v3 08/15] leds: leds-gpio: Add support for GPIO descriptors
Date: Wed, 01 Oct 2014 04:15:41 +0200	[thread overview]
Message-ID: <1490183.QvrzPxsV7q@vostro.rjw.lan> (raw)
In-Reply-To: <1852462.V1jlbi8OPt@vostro.rjw.lan>

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(-)

diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c
index 57ff20fecf57..c84e913527f0 100644
--- a/drivers/leds/leds-gpio.c
+++ b/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_struct *work)
 		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_classdev *led_cdev,
 	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_classdev *led_cdev,
 		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_classdev *led_cdev,
 {
 	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 gpio_led *template,
 {
 	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;
+		}
 
-	ret = devm_gpio_request(parent, template->gpio, template->name);
-	if (ret < 0)
-		return ret;
+		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);
+	}
 
 	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 gpio_led *template,
 	}
 	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);
 }
diff --git a/include/linux/leds.h b/include/linux/leds.h
index e43686472197..879a113b3d57 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -246,6 +246,7 @@ struct led_platform_data {
 struct gpio_led {
 	const char *name;
 	const char *default_trigger;
+	struct gpio_desc *gpiod;
 	unsigned 	gpio;
 	unsigned	active_low : 1;
 	unsigned	retain_state_suspended : 1;
-- 
1.8.4.5


