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Diffstat (limited to 'Documentation/leds/leds-sc27xx.rst')
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diff --git a/Documentation/leds/leds-sc27xx.rst b/Documentation/leds/leds-sc27xx.rst new file mode 100644 index 000000000..6bdf6ba3c --- /dev/null +++ b/Documentation/leds/leds-sc27xx.rst @@ -0,0 +1,27 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=================================== +Kernel driver for Spreadtrum SC27XX +=================================== + +/sys/class/leds/<led>/hw_pattern +-------------------------------- + +Specify a hardware pattern for the SC27XX LED. For the SC27XX +LED controller, it only supports 4 stages to make a single +hardware pattern, which is used to configure the rise time, +high time, fall time and low time for the breathing mode. + +For the breathing mode, the SC27XX LED only expects one brightness +for the high stage. To be compatible with the hardware pattern +format, we should set brightness as 0 for rise stage, fall +stage and low stage. + +- Min stage duration: 125 ms +- Max stage duration: 31875 ms + +Since the stage duration step is 125 ms, the duration should be +a multiplier of 125, like 125ms, 250ms, 375ms, 500ms ... 31875ms. + +Thus the format of the hardware pattern values should be: +"0 rise_duration brightness high_duration 0 fall_duration 0 low_duration". |