Dan, Thank you for the update. On 10/1/19 4:56 PM, Dan Murphy wrote: > Introduce a multicolor class that groups colored LEDs > within a LED node. > > 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. > > Signed-off-by: Dan Murphy <dmurphy@xxxxxx> > --- > .../ABI/testing/sysfs-class-led-multicolor | 35 +++ > Documentation/leds/index.rst | 1 + > Documentation/leds/leds-class-multicolor.rst | 96 +++++++ > drivers/leds/Kconfig | 10 + > drivers/leds/Makefile | 1 + > drivers/leds/led-class-multicolor.c | 268 ++++++++++++++++++ > include/linux/led-class-multicolor.h | 88 ++++++ > 7 files changed, 499 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-class-led-multicolor > create mode 100644 Documentation/leds/leds-class-multicolor.rst > create mode 100644 drivers/leds/led-class-multicolor.c > create mode 100644 include/linux/led-class-multicolor.h > > diff --git a/Documentation/ABI/testing/sysfs-class-led-multicolor b/Documentation/ABI/testing/sysfs-class-led-multicolor > new file mode 100644 > index 000000000000..65cb43de26e6 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-class-led-multicolor > @@ -0,0 +1,35 @@ > +What: /sys/class/leds/<led>/brightness > +Date: Sept 2019 > +KernelVersion: 5.5 > +Contact: Dan Murphy <dmurphy@xxxxxx> > +Description: read/write > + Writing to this file will update all LEDs within the group to a > + calculated percentage of what each color LED intensity is set > + to. The percentage is calculated via the equation below: > + > + led_brightness = brightness * <color>_intensity/<color>_max_intensity > + > + For additional details please refer to > + Documentation/leds/leds-class-multicolor.rst. > + > + The value of the color is from 0 to > + /sys/class/leds/<led>/max_brightness. > + > +What: /sys/class/leds/<led>/colors/<color>_intensity > +Date: Sept 2019 > +KernelVersion: 5.5 > +Contact: Dan Murphy <dmurphy@xxxxxx> > +Description: read/write > + The <color>_intensity file is created based on the color > + defined by the registrar of the class. > + There is one file per color presented. > + > + The value of the color is from 0 to > + /sys/class/leds/<led>/colors/<color>_max_intensity. > + > +What: /sys/class/leds/<led>/colors/<color>_max_intensity > +Date: Sept 2019 > +KernelVersion: 5.5 > +Contact: Dan Murphy <dmurphy@xxxxxx> > +Description: read only > + Maximum intensity level for the LED color. > diff --git a/Documentation/leds/index.rst b/Documentation/leds/index.rst > index 060f4e485897..bc70c6aa7138 100644 > --- a/Documentation/leds/index.rst > +++ b/Documentation/leds/index.rst > @@ -9,6 +9,7 @@ LEDs > > leds-class > leds-class-flash > + leds-class-multicolor > ledtrig-oneshot > ledtrig-transient > ledtrig-usbport > 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. > + > +Multicolor Class Control > +======================== > +The multicolor class presents the LED groups under a directory called "colors". > +This directory is a child under the LED parent node created by the led_class > +framework. The led_class framework is documented in led-class.rst within this > +documentation directory. > + > +Each colored LED will have two files created under the colors directory > +<color>_intensity and <color>_max_intensity. These files will contain > +one of LED_COLOR_ID_* definitions from the header > +include/dt-bindings/leds/common.h. > + > +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 Now when you have fixed file permissions in LED mc core the 'ls -l' should report them correctly, so this needs to be updated. [...] > +int devm_led_classdev_multicolor_register(struct device *parent, > + struct led_classdev_mc *mcled_cdev) > +{ > + struct led_classdev_mc **dr; > + int ret; > + > + dr = devres_alloc(devm_led_classdev_multicolor_release, > + sizeof(*dr), GFP_KERNEL); > + if (!dr) > + return -ENOMEM; > + > + ret = led_classdev_multicolor_register(parent, mcled_cdev); > + if (ret) { > + devres_free(dr); > + return ret; > + } > + > + *dr = mcled_cdev; > + devres_add(parent, dr); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_register); > + > +static int devm_led_classdev_multicolor_match(struct device *dev, > + void *res, void *data) > +{ > + struct mcled_cdev **p = res; s/mcled_cdev/led_classdev_mc/ > + > + if (WARN_ON(!p || !*p)) > + return 0; > + > + return *p == data; > +} > + [...] -- Best regards, Jacek Anaszewski
