| Message ID | 20190918145730.22805-4-jjhiblot@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add a generic driver for LED-based backlight | expand |
Jean, On 9/18/19 4:57 PM, Jean-Jacques Hiblot wrote: > 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> > --- > drivers/leds/led-class.c | 51 ++++++++++++++++++++++++++++++++++++++++ > include/linux/leds.h | 2 ++ > 2 files changed, 53 insertions(+) > > diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c > index 2b8f20f94128..e11177d77b4c 100644 > --- a/drivers/leds/led-class.c > +++ b/drivers/leds/led-class.c > @@ -264,6 +264,57 @@ 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_led_get - Resource-managed request of a LED device > + * @dev: LED consumer > + * @idx: 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. > + * > + * NOTE: At the moment, it supports only device-tree based LED lookup > + * > + * @return a pointer to a LED device or ERR_PTR(errno) on failure. > + */ > +struct led_classdev *__must_check devm_led_get(struct device *dev, > + int index) s/devm_led_get/devm_of_led_get/ > +{ > + 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_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 6f7371bc7757..88bf2ceaabe6 100644 > --- a/include/linux/leds.h > +++ b/include/linux/leds.h > @@ -199,6 +199,8 @@ extern 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_led_get(struct device *dev, > + int index); > > /** > * led_blink_set - set blinking with software fallback >
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 2b8f20f94128..e11177d77b4c 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -264,6 +264,57 @@ 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_led_get - Resource-managed request of a LED device + * @dev: LED consumer + * @idx: 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. + * + * NOTE: At the moment, it supports only device-tree based LED lookup + * + * @return a pointer to a LED device or ERR_PTR(errno) on failure. + */ +struct led_classdev *__must_check devm_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_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 6f7371bc7757..88bf2ceaabe6 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -199,6 +199,8 @@ extern 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_led_get(struct device *dev, + int index); /** * led_blink_set - set blinking with software fallback