.. SPDX-License-Identifier: GPL-2.0 ====================================== Samsung S2M Series PMIC RGB LED Driver ====================================== Description ----------- The RGB LED on the S2M series PMIC hardware features a three-channel LED that is grouped together as a single device. Furthermore, it supports 8-bit brightness control for each channel. This LED is typically used as a status indicator in mobile devices. It also supports various parameters for hardware patterns. The hardware pattern can be programmed using the "pattern" trigger, using the hw_pattern attribute. /sys/class/leds//repeat ---------------------------- The hardware supports only indefinitely repeating patterns. The repeat attribute must be set to -1 for hardware patterns to function. /sys/class/leds//hw_pattern -------------------------------- Specify a hardware pattern for the RGB LEDs. The pattern is a series of brightness levels and durations in milliseconds. There should be only one non-zero brightness level. Unlike the results described in leds-trigger-pattern, the transitions between on and off states are smoothed out by the hardware. Simple pattern:: "255 3000 0 1000" 255 -+ ''''''-. .-'''''''-. | '. .' '. | \ / \ | '. .' '. | '-.......-' '- 0 -+-------+-------+-------+-------+-------+-------+--> time (s) 0 1 2 3 4 5 6 As described in leds-trigger-pattern, it is also possible to use zero-length entries to disable the ramping mechanism. On-Off pattern:: "255 1000 255 0 0 1000 0 0" 255 -+ ------+ +-------+ +-------+ | | | | | | | | | | | | | | | | | | | +-------+ +-------+ +------- 0 -+-------+-------+-------+-------+-------+-------+--> time (s) 0 1 2 3 4 5 6