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| -rw-r--r-- | Documentation/leds/index.rst | 1 | ||||
| -rw-r--r-- | Documentation/leds/leds-s2m-rgb.rst | 60 |
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diff --git a/Documentation/leds/index.rst b/Documentation/leds/index.rst index bebf44004278..23fa9ff7aaf4 100644 --- a/Documentation/leds/index.rst +++ b/Documentation/leds/index.rst @@ -28,6 +28,7 @@ LEDs leds-lp5812 leds-mlxcpld leds-mt6370-rgb + leds-s2m-rgb leds-sc27xx leds-st1202 leds-qcom-lpg diff --git a/Documentation/leds/leds-s2m-rgb.rst b/Documentation/leds/leds-s2m-rgb.rst new file mode 100644 index 000000000000..4f89a8c89ea8 --- /dev/null +++ b/Documentation/leds/leds-s2m-rgb.rst @@ -0,0 +1,60 @@ +.. 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 |