cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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leds-blinkm.rst (2014B)

      1==================
      2Leds BlinkM driver
      3==================
      4
      5The leds-blinkm driver supports the devices of the BlinkM family.
      6
      7They are RGB-LED modules driven by a (AT)tiny microcontroller and
      8communicate through I2C. The default address of these modules is
      90x09 but this can be changed through a command. By this you could
     10dasy-chain up to 127 BlinkMs on an I2C bus.
     11
     12The device accepts RGB and HSB color values through separate commands.
     13Also you can store blinking sequences as "scripts" in
     14the controller and run them. Also fading is an option.
     15
     16The interface this driver provides is 2-fold:
     17
     18a) LED class interface for use with triggers
     19############################################
     20
     21The registration follows the scheme::
     22
     23  blinkm-<i2c-bus-nr>-<i2c-device-nr>-<color>
     24
     25  $ ls -h /sys/class/leds/blinkm-6-*
     26  /sys/class/leds/blinkm-6-9-blue:
     27  brightness  device  max_brightness  power  subsystem  trigger  uevent
     28
     29  /sys/class/leds/blinkm-6-9-green:
     30  brightness  device  max_brightness  power  subsystem  trigger  uevent
     31
     32  /sys/class/leds/blinkm-6-9-red:
     33  brightness  device  max_brightness  power  subsystem  trigger  uevent
     34
     35(same is /sys/bus/i2c/devices/6-0009/leds)
     36
     37We can control the colors separated into red, green and blue and
     38assign triggers on each color.
     39
     40E.g.::
     41
     42  $ cat blinkm-6-9-blue/brightness
     43  05
     44
     45  $ echo 200 > blinkm-6-9-blue/brightness
     46  $
     47
     48  $ modprobe ledtrig-heartbeat
     49  $ echo heartbeat > blinkm-6-9-green/trigger
     50  $
     51
     52
     53b) Sysfs group to control rgb, fade, hsb, scripts ...
     54#####################################################
     55
     56This extended interface is available as folder blinkm
     57in the sysfs folder of the I2C device.
     58E.g. below /sys/bus/i2c/devices/6-0009/blinkm
     59
     60  $ ls -h /sys/bus/i2c/devices/6-0009/blinkm/
     61  blue  green  red  test
     62
     63Currently supported is just setting red, green, blue
     64and a test sequence.
     65
     66E.g.::
     67
     68  $ cat *
     69  00
     70  00
     71  00
     72  #Write into test to start test sequence!#
     73
     74  $ echo 1 > test
     75  $
     76
     77  $ echo 255 > red
     78  $
     79
     80
     81
     82as of 6/2012
     83
     84dl9pf <at> gmx <dot> de