mirror of https://gitee.com/openkylin/linux.git
0cb8eb30d4
Some LEDs may have their brightness level changed autonomously (outside of kernel control) by hardware / firmware. This commit adds support for an optional brightness_hw_changed attribute to signal such changes to userspace (if a driver can detect them): What: /sys/class/leds/<led>/brightness_hw_changed Date: January 2017 KernelVersion: 4.11 Description: Last hardware set brightness level for this LED. Some LEDs may be changed autonomously by hardware/firmware. Only LEDs where this happens and the driver can detect this, will have this file. This file supports poll() to detect when the hardware changes the brightness. Reading this file will return the last brightness level set by the hardware, this may be different from the current brightness. Drivers which want to support this, simply add LED_BRIGHT_HW_CHANGED to their flags field and call led_classdev_notify_brightness_hw_changed() with the hardware set brightness when they detect a hardware / firmware triggered brightness change. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com> |
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| .. | ||
| 00-INDEX | ||
| leds-blinkm.txt | ||
| leds-class-flash.txt | ||
| leds-class.txt | ||
| leds-lm3556.txt | ||
| leds-lp55xx.txt | ||
| leds-lp3944.txt | ||
| leds-lp5521.txt | ||
| leds-lp5523.txt | ||
| leds-lp5562.txt | ||
| leds-mlxcpld.txt | ||
| ledtrig-oneshot.txt | ||
| ledtrig-transient.txt | ||
| ledtrig-usbport.txt | ||
| uleds.txt | ||