backlight: bd6107: Convert to use GPIO descriptor

The Rohm BD6107 driver can pass a fixed GPIO line using the old
GPIO API using platform data. As there are no in-tree users of this
platform data since 2013, we can convert this to use a GPIO descriptor
and require any out-of-tree consumers to pass the GPIO using
a machine descriptor table instead.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Author: Linus Walleij

drivers/video/backlight/bd6107.c

@@ -11,7 +11,7 @@
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/fb.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/platform_data/bd6107.h>
@@ -71,6 +71,7 @@ struct bd6107 {
 	struct i2c_client *client;
 	struct backlight_device *backlight;
 	struct bd6107_platform_data *pdata;
+	struct gpio_desc *reset;
 };
 
 static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data)
@@ -94,9 +95,10 @@ static int bd6107_backlight_update_status(struct backlight_device *backlight)
 		bd6107_write(bd, BD6107_MAINCNT1, brightness);
 		bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1);
 	} else {
-		gpio_set_value(bd->pdata->reset, 0);
+		/* Assert the reset line (gpiolib will handle active low) */
+		gpiod_set_value(bd->reset, 1);
 		msleep(24);
-		gpio_set_value(bd->pdata->reset, 1);
+		gpiod_set_value(bd->reset, 0);
 	}
 
 	return 0;
@@ -125,8 +127,8 @@ static int bd6107_probe(struct i2c_client *client,
 	struct bd6107 *bd;
 	int ret;
 
-	if (pdata == NULL || !pdata->reset) {
-		dev_err(&client->dev, "No reset GPIO in platform data\n");
+	if (pdata == NULL) {
+		dev_err(&client->dev, "No platform data\n");
 		return -EINVAL;
 	}
 
@@ -144,10 +146,16 @@ static int bd6107_probe(struct i2c_client *client,
 	bd->client = client;
 	bd->pdata = pdata;
 
-	ret = devm_gpio_request_one(&client->dev, pdata->reset,
-				    GPIOF_DIR_OUT | GPIOF_INIT_LOW, "reset");
-	if (ret < 0) {
+	/*
+	 * Request the reset GPIO line with GPIOD_OUT_HIGH meaning asserted,
+	 * so in the machine descriptor table (or other hardware description),
+	 * the line should be flagged as active low so this will assert
+	 * the reset.
+	 */
+	bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(bd->reset)) {
 		dev_err(&client->dev, "unable to request reset GPIO\n");
+		ret = PTR_ERR(bd->reset);
 		return ret;
 	}
 

include/linux/platform_data/bd6107.h

@@ -9,7 +9,6 @@ struct device;
 
 struct bd6107_platform_data {
 	struct device *fbdev;
-	int reset;			/* Reset GPIO */
 	unsigned int def_value;
 };