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Jacek Anaszewskif6ad3952015-03-04 08:14:24 -08001
2Flash LED handling under Linux
3==============================
4
5Some LED devices provide two modes - torch and flash. In the LED subsystem
6those modes are supported by LED class (see Documentation/leds/leds-class.txt)
7and LED Flash class respectively. The torch mode related features are enabled
8by default and the flash ones only if a driver declares it by setting
9LED_DEV_CAP_FLASH flag.
10
11In order to enable the support for flash LEDs CONFIG_LEDS_CLASS_FLASH symbol
12must be defined in the kernel config. A LED Flash class driver must be
13registered in the LED subsystem with led_classdev_flash_register function.
14
15Following sysfs attributes are exposed for controlling flash LED devices:
16(see Documentation/ABI/testing/sysfs-class-led-flash)
17 - flash_brightness
18 - max_flash_brightness
19 - flash_timeout
20 - max_flash_timeout
21 - flash_strobe
22 - flash_fault