Re: [PATCH 1/4] dt-bindings: leds: document property for LED triggers

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

On 03/06/2017 07:16 AM, Rafał Miłecki wrote:
> On 03/01/2017 10:04 PM, Jacek Anaszewski wrote:
>> On 02/28/2017 10:51 PM, Rafał Miłecki wrote:
>>> On 02/28/2017 10:38 PM, Jacek Anaszewski wrote:
>>>> I think that it would be simpler if we could initially see
>>>> a complete sample dts implementation containing all required DT
>>>> nodes. The example could contain timer trigger as well as usb-port
>>>> trigger specific bindings.
>>>
>>> Please take a look at attached patch. I used it on Tenda AC9 with:
>>>
>>> usb_trigger: usb-trigger {
>>>     trigger-type = "usbport";
>>>     ports = <&ohci_port1>, <&ehci_port1>;
>>> };
>>>
>>> usb {
>>>     label = "bcm53xx:blue:usb";
>>>     gpios = <&chipcommon 1 GPIO_ACTIVE_HIGH>;
>>>     triggers = <&usb_trigger>;
>>> };
>>
>> OK, I got it, thanks.
>>
>>>
>>>> I suppose that we should see DT nodes containing #list-cells
>>>> properties that define the quantity of phandle arguments.
>>>>
>>>> It seems that this approach allows for defining a list of elements
>>>> with variable number of arguments, i.e. what you were initially
>>>> asking for.
>>>
>>> Are you sure we need #list-cells? Can't we simply use
>>> of_count_phandle_with_args(np, "triggers", NULL);
>>> ?
>>
>> I'm not sure, I just read the function documentation :-)
>> I haven't verified nor have I used this API.
> 
> So we could use #list-cells to support something like:
> 
> usb {
>     label = "bcm53xx:blue:usb";
>     gpios = <&chipcommon 1 GPIO_ACTIVE_HIGH>;
>     triggers = <&usb_trigger 1 2>, <&timer_trigger 3 4 5>;
> };
> 
> but I don't see any need for this. Just specifying triggers like:
> triggers = <&usb_trigger>, <&timer_trigger>, <&foo>;
> should be always enough, especially with the new trigger nodes you
> suggested.

Indeed, it seems to be not needed for this approach.
I'm OK with this design.

-- 
Best regards,
Jacek Anaszewski