leds: bd2802: Convert to use GPIO descriptors

The Rohm BD2802 have no in-kernel users so we can drop the
GPIO number from the platform data and require users to
provide the GPIO line using machine descriptors.

As the descriptors come with inherent polarity inversion
semantics, we invert the calls to set the GPIO line such
that 0 means "unasserted" and 1 means "asserted".

Put a note in the driver that machine descriptor tables
will need to specify that the line is active low.

Cc: Kim Kyuwon <chammoru@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Pavel Machek <pavel@ucw.cz>

drivers/leds/leds-bd2802.c

@@ -10,7 +10,7 @@
 
 #include <linux/module.h>
 #include <linux/i2c.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/delay.h>
 #include <linux/leds.h>
 #include <linux/leds-bd2802.h>
@@ -67,6 +67,7 @@ struct led_state {
 struct bd2802_led {
 	struct bd2802_led_platform_data	*pdata;
 	struct i2c_client		*client;
+	struct gpio_desc		*reset;
 	struct rw_semaphore		rwsem;
 
 	struct led_state		led[2];
@@ -200,7 +201,7 @@ static void bd2802_update_state(struct bd2802_led *led, enum led_ids id,
 		return;
 
 	if (bd2802_is_all_off(led) && !led->adf_on) {
-		gpio_set_value(led->pdata->reset_gpio, 0);
+		gpiod_set_value(led->reset, 1);
 		return;
 	}
 
@@ -226,7 +227,7 @@ static void bd2802_configure(struct bd2802_led *led)
 
 static void bd2802_reset_cancel(struct bd2802_led *led)
 {
-	gpio_set_value(led->pdata->reset_gpio, 1);
+	gpiod_set_value(led->reset, 0);
 	udelay(100);
 	bd2802_configure(led);
 }
@@ -420,7 +421,7 @@ static void bd2802_disable_adv_conf(struct bd2802_led *led)
 						bd2802_addr_attributes[i]);
 
 	if (bd2802_is_all_off(led))
-		gpio_set_value(led->pdata->reset_gpio, 0);
+		gpiod_set_value(led->reset, 1);
 
 	led->adf_on = 0;
 }
@@ -670,8 +671,16 @@ static int bd2802_probe(struct i2c_client *client,
 	pdata = led->pdata = dev_get_platdata(&client->dev);
 	i2c_set_clientdata(client, led);
 
-	/* Configure RESET GPIO (L: RESET, H: RESET cancel) */
-	gpio_request_one(pdata->reset_gpio, GPIOF_OUT_INIT_HIGH, "RGB_RESETB");
+	/*
+	 * Configure RESET GPIO (L: RESET, H: RESET cancel)
+	 *
+	 * We request the reset GPIO as OUT_LOW which means de-asserted,
+	 * board files specifying this GPIO line in a machine descriptor
+	 * table should take care to specify GPIO_ACTIVE_LOW for this line.
+	 */
+	led->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(led->reset))
+		return PTR_ERR(led->reset);
 
 	/* Tacss = min 0.1ms */
 	udelay(100);
@@ -685,7 +694,7 @@ static int bd2802_probe(struct i2c_client *client,
 		dev_info(&client->dev, "return 0x%02x\n", ret);
 
 	/* To save the power, reset BD2802 after detecting */
-	gpio_set_value(led->pdata->reset_gpio, 0);
+	gpiod_set_value(led->reset, 1);
 
 	/* Default attributes */
 	led->wave_pattern = BD2802_PATTERN_HALF;
@@ -720,7 +729,7 @@ static int bd2802_remove(struct i2c_client *client)
 	struct bd2802_led *led = i2c_get_clientdata(client);
 	int i;
 
-	gpio_set_value(led->pdata->reset_gpio, 0);
+	gpiod_set_value(led->reset, 1);
 	bd2802_unregister_led_classdev(led);
 	if (led->adf_on)
 		bd2802_disable_adv_conf(led);
@@ -750,7 +759,7 @@ static int bd2802_suspend(struct device *dev)
 	struct i2c_client *client = to_i2c_client(dev);
 	struct bd2802_led *led = i2c_get_clientdata(client);
 
-	gpio_set_value(led->pdata->reset_gpio, 0);
+	gpiod_set_value(led->reset, 1);
 
 	return 0;
 }

include/linux/leds-bd2802.h

@@ -11,7 +11,6 @@
 #define _LEDS_BD2802_H_
 
 struct bd2802_led_platform_data{
-	int	reset_gpio;
 	u8	rgb_time;
 };