From e389240ad99292d52a4f8ff30f16830dc9c63779 Mon Sep 17 00:00:00 2001
From: Jean-Jacques Hiblot <jjhiblot@ti.com>
Date: Thu, 3 Oct 2019 10:28:10 +0200
Subject: [PATCH] leds: Add managed API to get a LED from a device driver
Git-commit: e389240ad99292d52a4f8ff30f16830dc9c63779
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322
If the LED is acquired by a consumer device with devm_led_get(), it is
automatically released when the device is detached.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/leds/led-class.c | 49 ++++++++++++++++++++++++++++++++++++++++
include/linux/leds.h | 2 ++
2 files changed, 51 insertions(+)
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 03ce74a2e6a9..0868f841d656 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -258,6 +258,55 @@ void led_put(struct led_classdev *led_cdev)
}
EXPORT_SYMBOL_GPL(led_put);
+static void devm_led_release(struct device *dev, void *res)
+{
+ struct led_classdev **p = res;
+
+ led_put(*p);
+}
+
+/**
+ * devm_of_led_get - Resource-managed request of a LED device
+ * @dev: LED consumer
+ * @index: index of the LED to obtain in the consumer
+ *
+ * The device node of the device is parse to find the request LED device.
+ * The LED device returned from this function is automatically released
+ * on driver detach.
+ *
+ * @return a pointer to a LED device or ERR_PTR(errno) on failure.
+ */
+struct led_classdev *__must_check devm_of_led_get(struct device *dev,
+ int index)
+{
+ struct led_classdev *led;
+ struct led_classdev **dr;
+
+ if (!dev)
+ return ERR_PTR(-EINVAL);
+
+ /* Not using device tree? */
+ if (!IS_ENABLED(CONFIG_OF) || !dev->of_node)
+ return ERR_PTR(-ENOTSUPP);
+
+ led = of_led_get(dev->of_node, index);
+ if (IS_ERR(led))
+ return led;
+
+ dr = devres_alloc(devm_led_release, sizeof(struct led_classdev *),
+ GFP_KERNEL);
+ if (!dr) {
+ led_put(led);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ *dr = led;
+ devres_add(dev, dr);
+
+ return led;
+}
+EXPORT_SYMBOL_GPL(devm_of_led_get);
+
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 dcfb6a325866..75353e5f9d13 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -199,6 +199,8 @@ void led_classdev_resume(struct led_classdev *led_cdev);
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);
/**
* led_blink_set - set blinking with software fallback
--
2.26.2