leds: Provide devm_of_led_get_optional()

Add an optional variant of devm_of_led_get(). It behaves the same as
devm_of_led_get() except where the LED doesn't exist. In this case,
instead of returning -ENOENT, the function returns NULL.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@traphandler.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20230728153731.3742339-2-jjhiblot@traphandler.com
Signed-off-by: Lee Jones <lee@kernel.org>

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 4758da2b59cf6873e18e928c77bda7e9d0ef9fc0..78068b06d009a0713b2b20ee9fc506efe122663c 100644 (file)
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -402,6 +402,31 @@ void led_remove_lookup(struct led_lookup_data *led_lookup)
 }
 EXPORT_SYMBOL_GPL(led_remove_lookup);
 
+/**
+ * devm_of_led_get_optional - Resource-managed request of an optional LED device
+ * @dev:       LED consumer
+ * @index:     index of the LED to obtain in the consumer
+ *
+ * The device node of the device is parsed to find the requested LED device.
+ * The LED device returned from this function is automatically released
+ * on driver detach.
+ *
+ * @return a pointer to a LED device, ERR_PTR(errno) on failure and NULL if the
+ * led was not found.
+ */
+struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev,
+                                                       int index)
+{
+       struct led_classdev *led;
+
+       led = devm_of_led_get(dev, index);
+       if (IS_ERR(led) && PTR_ERR(led) == -ENOENT)
+               return NULL;
+
+       return led;
+}
+EXPORT_SYMBOL_GPL(devm_of_led_get_optional);
+
 static int led_classdev_next_name(const char *init_name, char *name,
                                  size_t len)
 {

diff --git a/include/linux/leds.h b/include/linux/leds.h
index 7d428100b42b5cc631b01ff250838fe11588f2cf..8740b4e47f88922fa6ba3f6e861fc6b2a6e2e1f4 100644 (file)
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -313,6 +313,8 @@ extern struct led_classdev *of_led_get(struct device_node *np, int index);
 extern void led_put(struct led_classdev *led_cdev);
 struct led_classdev *__must_check devm_of_led_get(struct device *dev,
                                                  int index);
+struct led_classdev *__must_check devm_of_led_get_optional(struct device *dev,
+                                                 int index);
 
 /**
  * led_blink_set - set blinking with software fallback