Jacek
On 1/7/19 3:13 PM, Jacek Anaszewski wrote:
> Hi Vesa,
>
> On 1/5/19 1:39 AM, Vesa Jääskeläinen wrote:
>> Hi Jacek,
>>
>> On 04/01/2019 23.37, Jacek Anaszewski wrote:
>>> But, aside from that hypothetic issue, we need a solution for
>>> LEDn_BRIGHTNESS feature of lp5024, i.e. setting color intensity
>>> via a single register write. How would you propose to address that?
>>
>> You could model it to something like this in device tree:
>>
>> led-module @ <i2c-address> {
>> compatible = "lp5024";
>>
>> // There is in hardware setup to use either linear or
>> // logarithmic scaling:
>> //enable-logarithmic-brightness;
>>
>> led0 {
>> // this will create led instance for LED0 in lp5024
>> label = "lp-led0";
>>
>> // This specifies LED number within lp5024
>> led-index = <0>; // set output-base as 0*3 == 0
>>
>> element-red {
>> // refers to OUT0
>> output-offset = <0>;
>> };
>>
>> element-green {
>> // refers to OUT1
>> output-offset = <1>;
>> };
>>
>> element-blue {
>> // refers to OUT2
>> output-offset = <2>;
>> };
>>
>> };
>>
>> led1 {
>> // this will create led instance for LED1 in lp5024
>> label = "lp-led1";
>>
>> // This specifies LED number within lp5024
>> led-index = <1>; // set output-base as 1*3 == 3
>>
>> element-red {
>> // refers to OUT3
>> output-offset = <0>;
>> };
>>
>> element-green {
>> // refers to OUT4
>> output-offset = <1>;
>> };
>>
>> element-blue {
>> // refers to OUT5
>> output-offset = <2>;
>> };
>>
>> };
>>
>> bank-led {
>> // this will create led instance for bank leds in lp5024
>> label = "lp-bank-led";
>>
>> // configured bank led configuration
>> led-index = <2 3 4 5 6 7>;
>> // As here is list of led-indices this entry is
>> // assumed to be bank configuration. Bank mode is enable
>> // for the indices.
>>
>> // set output-base as BANK A
>>
>> element-red {
>> // refers to BANK A
>> output-offset = <0>;
>> };
>>
>> element-green {
>> // refers to BANK B
>> output-offset = <1>;
>> };
>>
>> element-blue {
>> // refers to BANK C
>> output-offset = <2>;
>> };
>> };
>> };
>>
>> This would then create three led instances and each led instance has brightness setting and that goes straight to hardware.
>>
>> If one would want to override hardware control for brightness then I suppose you would define in led node something like:
>>
>> brightness-model = "hsl"
>>
>> This would then pick red, green and blue elements for hsl calculations and others color elements for linear. LED specific hardware brightness would then be either 0 or 0xFF depending if all of LED color elements are zero or not.
>>
>> Would that kind of model work?
>
> I'd prefer to have single RGB LED device. And your DT design
> is unnecessarily complex and a bit confusing.
+1 to that comment
>
> Also, you provided scarce information about sysfs interface.
> It would be nice to see the sequence of commands.
>
--
------------------
Dan Murphy
