From 3ef7de5304edf60d0b8674dd7cdacc104e15a93c Mon Sep 17 00:00:00 2001 From: Jacek Anaszewski Date: Wed, 20 Aug 2014 06:41:55 -0700 Subject: [PATCH] leds: Improve and export led_update_brightness led_update_brightness helper function used to be exploited only locally in the led-class.c module, where its result was being passed to the brightness_show sysfs callback. With the introduction of v4l2-flash subdevice the same functionality becomes required for reading current brightness from a LED device. This patch adds checking of return value of the brightness_get callback and moves the led_update_brightness() function to the LED subsystem public API. Signed-off-by: Jacek Anaszewski Acked-by: Kyungmin Park Cc: Richard Purdie Signed-off-by: Bryan Wu --- drivers/leds/led-class.c | 6 ------ drivers/leds/led-core.c | 16 ++++++++++++++++ include/linux/leds.h | 10 ++++++++++ 3 files changed, 26 insertions(+), 6 deletions(-) diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 71666a40b79a..7440c58b8e6f 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -24,12 +24,6 @@ static struct class *leds_class; -static void led_update_brightness(struct led_classdev *led_cdev) -{ - if (led_cdev->brightness_get) - led_cdev->brightness = led_cdev->brightness_get(led_cdev); -} - static ssize_t brightness_show(struct device *dev, struct device_attribute *attr, char *buf) { diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c index 50b579ad948e..aaa8eba9099f 100644 --- a/drivers/leds/led-core.c +++ b/drivers/leds/led-core.c @@ -127,3 +127,19 @@ void led_set_brightness(struct led_classdev *led_cdev, __led_set_brightness(led_cdev, brightness); } EXPORT_SYMBOL(led_set_brightness); + +int led_update_brightness(struct led_classdev *led_cdev) +{ + int ret = 0; + + if (led_cdev->brightness_get) { + ret = led_cdev->brightness_get(led_cdev); + if (ret >= 0) { + led_cdev->brightness = ret; + return 0; + } + } + + return ret; +} +EXPORT_SYMBOL(led_update_brightness); diff --git a/include/linux/leds.h b/include/linux/leds.h index f2e1cbc25705..a57611d0c94e 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -140,6 +140,16 @@ extern void led_blink_set_oneshot(struct led_classdev *led_cdev, */ extern void led_set_brightness(struct led_classdev *led_cdev, enum led_brightness brightness); +/** + * led_update_brightness - update LED brightness + * @led_cdev: the LED to query + * + * Get an LED's current brightness and update led_cdev->brightness + * member with the obtained value. + * + * Returns: 0 on success or negative error value on failure + */ +extern int led_update_brightness(struct led_classdev *led_cdev); /* * LED Triggers -- 2.34.1