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

["Rafał Miłecki" <rafal@milecki.pl>]

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.