Revision 02ef0f3c128bbae76da7265c4a6f66c840fd7d25 authored by Phil Elwell on 06 February 2015, 13:50:57 UTC, committed by popcornmix on 08 January 2017, 11:39:53 UTC
The "input" trigger makes the associated GPIO an input.  This is to support
the Raspberry Pi PWR LED, which is driven by external hardware in normal use.

N.B. pwr_led is not available on Model A or B boards.

leds-gpio: Implement the brightness_get method

The power LED uses some clever logic that means it is driven
by a voltage measuring circuit when configured as input, otherwise
it is driven by the GPIO output value. This patch wires up the
brightness_get method for leds-gpio so that user-space can monitor
the LED value via /sys/class/gpio/led1/brightness. Using the input
trigger this returns an indication of the system power health,
otherwise it is just whatever value the trigger has written most
recently.

See: https://github.com/raspberrypi/linux/issues/1064
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.cocciconfig -rw-r--r-- 59 bytes
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