gpio: Pass GPIO label down to gpiod_request

Currently all users of fwnode_get_named_gpiod() have no way to
specify a label for the GPIO. So GPIOs listed in debugfs are shown
with label "?". With this change a proper label is used.

Also adjust all users so they can pass a label, properly retrieved
from device tree properties.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/devres.c

@@ -138,7 +138,8 @@ EXPORT_SYMBOL(devm_gpiod_get_index);
 struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
 					    const char *con_id,
 					    struct fwnode_handle *child,
-					    enum gpiod_flags flags)
+					    enum gpiod_flags flags,
+					    const char *label)
 {
 	static const char * const suffixes[] = { "gpios", "gpio" };
 	char prop_name[32]; /* 32 is max size of property name */
@@ -159,7 +160,7 @@ struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
 			snprintf(prop_name, sizeof(prop_name), "%s",
 							       suffixes[i]);
 
-		desc = fwnode_get_named_gpiod(child, prop_name, flags);
+		desc = fwnode_get_named_gpiod(child, prop_name, flags, label);
 		if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
 			break;
 	}

drivers/gpio/gpiolib.c

@@ -3325,7 +3325,8 @@ EXPORT_SYMBOL_GPL(gpiod_get_index);
  */
 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
 					 const char *propname,
-					 enum gpiod_flags dflags)
+					 enum gpiod_flags dflags,
+					 const char *label)
 {
 	struct gpio_desc *desc = ERR_PTR(-ENODEV);
 	unsigned long lflags = 0;
@@ -3356,7 +3357,7 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
 	if (IS_ERR(desc))
 		return desc;
 
-	ret = gpiod_request(desc, NULL);
+	ret = gpiod_request(desc, label);
 	if (ret)
 		return ERR_PTR(ret);
 

drivers/input/keyboard/gpio_keys.c

@@ -481,7 +481,8 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
 	spin_lock_init(&bdata->lock);
 
 	if (child) {
-		bdata->gpiod = devm_get_gpiod_from_child(dev, NULL, child, GPIOD_IN);
+		bdata->gpiod = devm_get_gpiod_from_child(dev, NULL, child,
+							 GPIOD_IN, desc);
 		if (IS_ERR(bdata->gpiod)) {
 			error = PTR_ERR(bdata->gpiod);
 			if (error == -ENOENT) {

drivers/input/keyboard/gpio_keys_polled.c

@@ -305,7 +305,8 @@ static int gpio_keys_polled_probe(struct platform_device *pdev)
 
 			bdata->gpiod = devm_get_gpiod_from_child(dev, NULL,
 								 child,
-								 GPIOD_IN);
+								 GPIOD_IN,
+								 button->desc);
 			if (IS_ERR(bdata->gpiod)) {
 				error = PTR_ERR(bdata->gpiod);
 				if (error != -EPROBE_DEFER)

drivers/leds/leds-gpio.c

@@ -174,12 +174,6 @@ static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
 		const char *state = NULL;
 		struct device_node *np = to_of_node(child);
 
-		led.gpiod = devm_get_gpiod_from_child(dev, NULL, child, GPIOD_ASIS);
-		if (IS_ERR(led.gpiod)) {
-			fwnode_handle_put(child);
-			return ERR_CAST(led.gpiod);
-		}
-
 		ret = fwnode_property_read_string(child, "label", &led.name);
 		if (ret && IS_ENABLED(CONFIG_OF) && np)
 			led.name = np->name;
@@ -188,6 +182,13 @@ static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
 			return ERR_PTR(-EINVAL);
 		}
 
+		led.gpiod = devm_get_gpiod_from_child(dev, NULL, child,
+						      GPIOD_ASIS, led.name);
+		if (IS_ERR(led.gpiod)) {
+			fwnode_handle_put(child);
+			return ERR_CAST(led.gpiod);
+		}
+
 		fwnode_property_read_string(child, "linux,default-trigger",
 					    &led.default_trigger);
 

drivers/video/fbdev/amba-clcd-nomadik.c

@@ -185,22 +185,26 @@ static void tpg110_init(struct device *dev, struct device_node *np,
 	dev_info(dev, "TPG110 display init\n");
 
 	/* This asserts the GRESTB signal, putting the display into reset */
-	grestb = devm_get_gpiod_from_child(dev, "grestb", &np->fwnode, GPIOD_OUT_HIGH);
+	grestb = devm_get_gpiod_from_child(dev, "grestb", &np->fwnode,
+					   GPIOD_OUT_HIGH, "grestb");
 	if (IS_ERR(grestb)) {
 		dev_err(dev, "no GRESTB GPIO\n");
 		return;
 	}
-	scen = devm_get_gpiod_from_child(dev, "scen", &np->fwnode, GPIOD_OUT_LOW);
+	scen = devm_get_gpiod_from_child(dev, "scen", &np->fwnode,
+					 GPIOD_OUT_LOW, "scen");
 	if (IS_ERR(scen)) {
 		dev_err(dev, "no SCEN GPIO\n");
 		return;
 	}
-	scl = devm_get_gpiod_from_child(dev, "scl", &np->fwnode, GPIOD_OUT_LOW);
+	scl = devm_get_gpiod_from_child(dev, "scl", &np->fwnode, GPIOD_OUT_LOW,
+					"scl");
 	if (IS_ERR(scl)) {
 		dev_err(dev, "no SCL GPIO\n");
 		return;
 	}
-	sda = devm_get_gpiod_from_child(dev, "sda", &np->fwnode, GPIOD_OUT_LOW);
+	sda = devm_get_gpiod_from_child(dev, "sda", &np->fwnode, GPIOD_OUT_LOW,
+					"sda");
 	if (IS_ERR(sda)) {
 		dev_err(dev, "no SDA GPIO\n");
 		return;

include/linux/gpio/consumer.h

@@ -136,11 +136,13 @@ struct fwnode_handle;
 
 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
 					 const char *propname,
-					 enum gpiod_flags dflags);
+					 enum gpiod_flags dflags,
+					 const char *label);
 struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
 					    const char *con_id,
 					    struct fwnode_handle *child,
-					    enum gpiod_flags flags);
+					    enum gpiod_flags flags,
+					    const char *label);
 #else /* CONFIG_GPIOLIB */
 
 static inline int gpiod_count(struct device *dev, const char *con_id)
@@ -416,7 +418,8 @@ struct fwnode_handle;
 static inline
 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
 					 const char *propname,
-					 enum gpiod_flags dflags)
+					 enum gpiod_flags dflags,
+					 const char *label)
 {
 	return ERR_PTR(-ENOSYS);
 }
@@ -425,7 +428,8 @@ static inline
 struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
 					    const char *con_id,
 					    struct fwnode_handle *child,
-					    enum gpiod_flags flags)
+					    enum gpiod_flags flags,
+					    const char *label)
 {
 	return ERR_PTR(-ENOSYS);
 }