| .. 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/<led>/repeat |
| ---------------------------- |
| |
| The hardware supports only indefinitely repeating patterns. The repeat |
| attribute must be set to -1 for hardware patterns to function. |
| |
| /sys/class/leds/<led>/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 |
