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+==================
+Leds BlinkM driver
+==================
+
+The leds-blinkm driver supports the devices of the BlinkM family.
+
+They are RGB-LED modules driven by a (AT)tiny microcontroller and
+communicate through I2C. The default address of these modules is
+0x09 but this can be changed through a command. By this you could
+daisy-chain up to 127 BlinkMs on an I2C bus.
+
+The device accepts RGB and HSB color values through separate commands.
+Also you can store blinking sequences as "scripts" in
+the controller and run them. Also fading is an option.
+
+The interface this driver provides is 3-fold:
+
+a) LED multicolor class interface for use with triggers
+#######################################################
+
+The registration follows the scheme::
+
+  blinkm-<i2c-bus-nr>-<i2c-device-nr>:rgb:indicator
+
+  $ ls -h /sys/class/leds/blinkm-1-9:rgb:indicator
+  brightness  device  max_brightness  multi_index  multi_intensity  power  subsystem  trigger  uevent
+
+Hue is controlled by the multi_intensity file and lightness is controlled by
+the brightness file.
+
+The order in which to write the intensity values can be found in multi_index.
+Exactly three values between 0 and 255 must be written to multi_intensity to
+change the color::
+
+  $ echo 255 100 50 > multi_intensity
+
+The overall lightness be changed by writing a value between 0 and 255 to the
+brightness file.
+
+b) LED class interface for use with triggers
+############################################
+
+The registration follows the scheme::
+
+  blinkm-<i2c-bus-nr>-<i2c-device-nr>-<color>
+
+  $ ls -h /sys/class/leds/blinkm-6-*
+  /sys/class/leds/blinkm-6-9-blue:
+  brightness  device  max_brightness  power  subsystem  trigger  uevent
+
+  /sys/class/leds/blinkm-6-9-green:
+  brightness  device  max_brightness  power  subsystem  trigger  uevent
+
+  /sys/class/leds/blinkm-6-9-red:
+  brightness  device  max_brightness  power  subsystem  trigger  uevent
+
+(same is /sys/bus/i2c/devices/6-0009/leds)
+
+We can control the colors separated into red, green and blue and
+assign triggers on each color.
+
+E.g.::
+
+  $ cat blinkm-6-9-blue/brightness
+  05
+
+  $ echo 200 > blinkm-6-9-blue/brightness
+  $
+
+  $ modprobe ledtrig-heartbeat
+  $ echo heartbeat > blinkm-6-9-green/trigger
+  $
+
+
+b) Sysfs group to control rgb, fade, hsb, scripts ...
+#####################################################
+
+This extended interface is available as folder blinkm
+in the sysfs folder of the I2C device.
+E.g. below /sys/bus/i2c/devices/6-0009/blinkm
+
+  $ ls -h /sys/bus/i2c/devices/6-0009/blinkm/
+  blue  green  red  test
+
+Currently supported is just setting red, green, blue
+and a test sequence.
+
+E.g.::
+
+  $ cat *
+  00
+  00
+  00
+  #Write into test to start test sequence!#
+
+  $ echo 1 > test
+  $
+
+  $ echo 255 > red
+  $
+
+
+
+as of 07/2024
+
+dl9pf <at> gmx <dot> de
+jstrauss <at> mailbox <dot> org