This patch adds led_set_brightness_nosleep function as well as LED_BRIGHTNESS_FAST flag. The flag, when set by a driver means that its brightness_set op is guaranteed not to sleep. Basing on this information the function decides whether brightness should be set in an asynchronous or synchronous way.
Signed-off-by: Jacek Anaszewski <[email protected]> Cc: Bryan Wu <[email protected]> Cc: Andrew Lunn <[email protected]> Cc: Sakari Ailus <[email protected]> Cc: Pavel Machek <[email protected]> Cc: Stas Sergeev <[email protected]> --- drivers/leds/leds.h | 18 ++++++++++++++++++ include/linux/leds.h | 3 ++- 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h index ca38f6a..6c56142 100644 --- a/drivers/leds/leds.h +++ b/drivers/leds/leds.h @@ -2,8 +2,10 @@ * LED Core * * Copyright 2005 Openedhand Ltd. + * Copyright 2014, 2015 Samsung Electronics Co., Ltd. * * Author: Richard Purdie <[email protected]> + * Author: Jacek Anaszewski <[email protected]> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -23,6 +25,22 @@ static inline void led_set_brightness_async(struct led_classdev *led_cdev, schedule_work(&led_cdev->set_brightness_work); } +static inline void led_set_brightness_nosleep(struct led_classdev *led_cdev, + enum led_brightness value) +{ + if (led_cdev->flags & LED_BRIGHTNESS_FAST) { + led_set_brightness_sync(led_cdev, value); + return; + } + + /* + * Delegate setting brightness to a work queue task only for slow + * LEDs as the FAST ones are guaranteed not to sleep while setting + * brightness. + */ + led_set_brightness_async(led_cdev, value); +} + static inline int led_get_brightness(struct led_classdev *led_cdev) { return led_cdev->brightness; diff --git a/include/linux/leds.h b/include/linux/leds.h index a72ab56..2fdfc13 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -49,9 +49,10 @@ struct led_classdev { #define SET_BRIGHTNESS_SYNC (1 << 22) #define LED_DEV_CAP_FLASH (1 << 23) #define LED_BLINK_DISABLE (1 << 24) +#define LED_BRIGHTNESS_FAST (1 << 25) /* Set LED brightness level */ - /* Must not sleep, use a workqueue if needed */ + /* Must not sleep if the driver sets LED_BRIGHTNESS_FAST flag */ void (*brightness_set)(struct led_classdev *led_cdev, enum led_brightness brightness); /* -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-leds" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
