Re: turris omnia leds again: question

[Jacek Anaszewski <jacek.anaszewski@gmail.com>]

Hi Marek,

On 3/10/20 6:38 PM, Marek Behun wrote:
> Hi,
> 
> I am going to try to send driver for Omnia LEDs again. The last time
> there was a problem: on 05/01/2019 Jacek wrote:
> 
>> I wonder if we're doing right merging this driver in this form.
>> We break the rule one-led-class-device-per-one-channel. We don't
>> have LED multi color support yet, so this should support RGB LEDs
>> in the old manner. Or switch to using LED multi color class.
> 
>> Once we will have LED multi color class, we will be able to add the
>> support for it to the driver and make the driver configurable to be
>> able to expose old interface or the LED multi color one.
> 
>> Moreover, the bindings should use led-sources property for grouping
>> three channels under single LED class device. This is certainly to be
>> fixed.
> 
> So I am going to try to modify the driver so that each channel creates
> one LED class device. Do I understand this correctly then, that this
> way when there are three channels (RGB) on one LED, all the 3 device
> tree nodes for should have the same reg property, but different
> led-sources property? Eg:
> 
>   led@0,0 {
>     reg = <0>;
>     led-sources = <0>;
>     label = "omnia::heartbeat::red";
>   };
> 
>   led@0,1 {
>     reg = <0>;
>     led-sources = <1>;
>     label = "omnia::heartbeat::green";
>   };
> 
>   led@0,2 {
>     reg = <0>;
>     led-sources = <2>;
>     label = "omnia::heartbeat::blue";
>   };
> 
> Or did I misinterpret the led-sources property?

This is what I proposed back then, strangely that message wasn't
archived by bots, or maybe it resides only in my outbox...

--------------

LED sub-node properties:
 - reg :                Must be from 0x0 to 0xb, since there are 12 RGB
LEDs on this
                        controller.
 - label :              (optional)
   see Documentation/devicetree/bindings/leds/common.txt
 - linux,default-trigger : (optional)
   see Documentation/devicetree/bindings/leds/common.txt
 - led-sources : Each child node should describe RGB LED it controls,
                 by listing corresponding iout identifiers:
        0 - RGB LED 0: red
        1 - RGB LED 0: green
        2 - RGB LED 0: blue
        3 - RGB LED 1: red
        4 - RGB LED 1: green
        5 - RGB LED 1: blue
        6 - RGB LED 2: red
        7 - RGB LED 2: green
        8 - RGB LED 2: blue
        9 - RGB LED 3: red
        10 - RGB LED 3: green
        11 - RGB LED 3: blue
    ... and list all the iouts, maybe other names will be more
            appropriate for this device, feel free to propose something



Example:

        led-controller@2b {
                compatible = "cznic,turris-omnia-leds";
                reg = <0x2b>;
                #address-cells = <1>;
                #size-cells = <0>;

                led@0 {
                        reg = <0x0>;
                        label = "userB";
                        linux,default-trigger = "heartbeat";
                        led-sources = <0 1 2>;
                };

                led@1 {
                        reg = <0x1>;
                        label = "userA";
                        led-sources = <3 4 5>;
                };

                led@2 {
                        reg = <0x2>;
                        label = "pci3";
                        led-sources = <6 7 8>;
                };

                led@3 {
                        reg = <0x3>;
                        label = "pci2";
                        led-sources = <9 10 11>;
                };
                ...
--------------


Of course now label should be replaced with color and function
properties. I've just reviewed that patch set and realized that
we agreed upon setting max_brightness to 1 for all LEDs, right?

-- 
Best regards,
Jacek Anaszewski