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Documentation / leds / leds-blinkm.txt


Based on kernel version 4.16.1. Page generated on 2018-04-09 11:53 EST.

1	The leds-blinkm driver supports the devices of the BlinkM family.
2	
3	They are RGB-LED modules driven by a (AT)tiny microcontroller and
4	communicate through I2C. The default address of these modules is
5	0x09 but this can be changed through a command. By this you could
6	dasy-chain up to 127 BlinkMs on an I2C bus.
7	
8	The device accepts RGB and HSB color values through separate commands.
9	Also you can store blinking sequences as "scripts" in
10	the controller and run them. Also fading is an option.
11	
12	The interface this driver provides is 2-fold:
13	
14	a) LED class interface for use with triggers
15	############################################
16	
17	The registration follows the scheme:
18	blinkm-<i2c-bus-nr>-<i2c-device-nr>-<color>
19	
20	$ ls -h /sys/class/leds/blinkm-6-*
21	/sys/class/leds/blinkm-6-9-blue:
22	brightness  device  max_brightness  power  subsystem  trigger  uevent
23	
24	/sys/class/leds/blinkm-6-9-green:
25	brightness  device  max_brightness  power  subsystem  trigger  uevent
26	
27	/sys/class/leds/blinkm-6-9-red:
28	brightness  device  max_brightness  power  subsystem  trigger  uevent
29	
30	(same is /sys/bus/i2c/devices/6-0009/leds)
31	
32	We can control the colors separated into red, green and blue and
33	assign triggers on each color.
34	
35	E.g.:
36	
37	$ cat blinkm-6-9-blue/brightness
38	05
39	
40	$ echo 200 > blinkm-6-9-blue/brightness
41	$
42	
43	$ modprobe ledtrig-heartbeat
44	$ echo heartbeat > blinkm-6-9-green/trigger
45	$
46	
47	
48	b) Sysfs group to control rgb, fade, hsb, scripts ...
49	#####################################################
50	
51	This extended interface is available as folder blinkm
52	in the sysfs folder of the I2C device.
53	E.g. below /sys/bus/i2c/devices/6-0009/blinkm
54	
55	$ ls -h /sys/bus/i2c/devices/6-0009/blinkm/
56	blue  green  red  test
57	
58	Currently supported is just setting red, green, blue
59	and a test sequence.
60	
61	E.g.:
62	
63	$ cat *
64	00
65	00
66	00
67	#Write into test to start test sequence!#
68	
69	$ echo 1 > test
70	$
71	
72	$ echo 255 > red
73	$
74	
75	
76	
77	as of 6/2012
78	
79	dl9pf <at> gmx <dot> de
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