LXR linux/Documentation/leds/leds-blinkm.rst

   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
  85