Hi! > diff --git a/Documentation/leds/leds-class-multicolor.rst b/Documentation/leds/leds-class-multicolor.rst > new file mode 100644 > index 000000000000..87a1588d7619 > --- /dev/null > +++ b/Documentation/leds/leds-class-multicolor.rst > @@ -0,0 +1,96 @@ > +==================================== > +Multi Color LED handling under Linux > +==================================== > + > +Description > +=========== > +The multi color class groups monochrome LEDs and allows controlling two > +aspects of the final combined color: hue and lightness. The former is > +controlled via <color>_intensity files and the latter is controlled > +via brightness file. > + > +For more details on hue and lightness notions please refer to > +https://en.wikipedia.org/wiki/CIECAM02. > + > +Note that intensity files only cache the written value and the actual > +change of hardware state occurs upon writing brightness file. This > +allows for changing many factors of the perceived color in a virtually > +unnoticeable way for the human observer. So unlike previous versions, userspace will need to write 4 files instead of one in the common case. > +Directory Layout Example > +======================== > +root:/sys/class/leds/rgb:grouped_leds# ls -lR colors/ > +-rw-rwxr-- 1 root root 4096 Jul 7 03:10 red_max_intensity > +--w--wx-w- 1 root root 4096 Jul 7 03:10 red_intensity > +-rw-rwxr-- 1 root root 4096 Jul 7 03:10 green_max_intensity > +--w--wx-w- 1 root root 4096 Jul 7 03:10 green_intensity > +-rw-rwxr-- 1 root root 4096 Jul 7 03:10 blue_max_intensity > +--w--wx-w- 1 root root 4096 Jul 7 03:10 blue_intensity Permissions are way off here. > +A user first writes the color LED brightness file with the brightness level that > +is necessary to achieve a blueish violet output from the RGB LED group. > + > +echo 138 > /sys/class/leds/rgb:grouped_leds/red_intensity > +echo 43 > /sys/class/leds/rgb:grouped_leds/green_intensity > +echo 226 > /sys/class/leds/rgb:grouped_leds/blue_intensity No, you can't tell what kind of color this will result in. Will you be on ELCE/OSS in Lyon? Best regards, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
Attachment:
signature.asc
Description: Digital signature