Re: [PATCH v9 4/5] dt-bindings: backlight: Add led-backlight binding

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

On 10/8/19 5:00 PM, Rob Herring wrote:
> On Tue, Oct 8, 2019 at 8:30 AM Jean-Jacques Hiblot <jjhiblot@ti.com> wrote:
>>
>> Rob,
>>
>> On 08/10/2019 14:51, Jean-Jacques Hiblot wrote:
>>> Hi Rob,
>>>
>>> On 07/10/2019 18:15, Rob Herring wrote:
>>>> Please send DT bindings to DT list or it's never in my queue. IOW,
>>>> send patches to the lists that get_maintainers.pl tells you to.
>>>>
>>>> On Mon, Oct 7, 2019 at 7:45 AM Jean-Jacques Hiblot <jjhiblot@ti.com>
>>>> wrote:
>>>>> Add DT binding for led-backlight.
>>>>>
>>>>> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
>>>>> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
>>>>> Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
>>>>> ---
>>>>>   .../bindings/leds/backlight/led-backlight.txt | 28
>>>>> +++++++++++++++++++
>>>>>   1 file changed, 28 insertions(+)
>>>>>   create mode 100644
>>>>> Documentation/devicetree/bindings/leds/backlight/led-backlight.txt
>>>> Please make this a DT schema.
>>>
>>> OK.
>>>
>>> BTW I used "make dt_binding_check" but had to fix a couple of YAMLs
>>> file to get it to work. Do you have a kernel tree with already all the
>>> YAML files in good shape ? Or do you want me to post the changes to
>>> devicetree@vger.kernel.org ?
>>>
>>>
>>>>
>>>>> diff --git
>>>>> a/Documentation/devicetree/bindings/leds/backlight/led-backlight.txt
>>>>> b/Documentation/devicetree/bindings/leds/backlight/led-backlight.txt
>>>>> new file mode 100644
>>>>> index 000000000000..4c7dfbe7f67a
>>>>> --- /dev/null
>>>>> +++
>>>>> b/Documentation/devicetree/bindings/leds/backlight/led-backlight.txt
>>>>> @@ -0,0 +1,28 @@
>>>>> +led-backlight bindings
>>>>> +
>>>>> +This binding is used to describe a basic backlight device made of
>>>>> LEDs.
>>>>> +It can also be used to describe a backlight device controlled by
>>>>> the output of
>>>>> +a LED driver.
>>>>> +
>>>>> +Required properties:
>>>>> +  - compatible: "led-backlight"
>>>>> +  - leds: a list of LEDs
>>>> 'leds' is already used as a node name and mixing is not ideal.

for the record: child node names (if that was what you had on mind)
have singular form 'led'.

>>>> We already have 'flash-leds' in use and with the same definition, so
>>>> lets continue that and use 'backlight-leds'.
>>> OK
>>
>> I am taking that back. I have added of_get_led() and devm_of_get_led()
>> to the LED core to make it easier to get a LED from the DT. I modeled
>> the interface like it is done for PWM, PHYs or clocks. The property
>> containing list/array of phandle  is always named the same. To get one
>> particular PWM/PHY/clock, a identifier (name or integer) must be provided.
> 
> It can be done as we do support that with '-gpios', but yes, it is a
> bit more painful to deal with.
> 
>> So unless there is a strong incentive to do otherwise I's rather keep
>> this name here.
> 
> In that case, this needs to be documented as a common LED binding, not
> something hidden away in this binding.
> 
> Rob
> 

-- 
Best regards,
Jacek Anaszewski