Re: [PATCHv4 1/2] drivers: input: keypad: Add device tree support

Poddar, Sourav
2012-04-26T06:33:27Z

Hi Stephen,

On Wed, Apr 25, 2012 at 9:18 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
> On 04/25/2012 03:26 AM, Sourav Poddar wrote:
>> Update the Documentation with omap4 keypad device tree
>> binding information.
>> Add device tree support for omap4 keypad driver.
>
>> diff --git a/Documentation/devicetree/bindings/input/omap-keypad.txt b/Documentation/devicetree/bindings/input/omap-keypad.txt
>
>> +Required Board Specific Properties, in addition to those specified by
>> +the shared matrix-keyboard bindings:
>> +- keypad,num-rows: Number of row lines connected to the keypad
>> +  controller.
>> +
>> +- keypad,num-columns: Number of column lines connected to the
>> +  keypad controller.
>
> I'm not sure if "keypad," is the appropriate prefix here. If the
> properties are specific to this one TI/OMAP binding, "ti," might be a
> better prefix. However, if they're more generally applicable, maybe
> "linux," to match "linux,keymap"?
>
Yes, the idea was to make this binding more generic. Hence no "ti/omap"
prefix were used.
'linux' prefix denotes bindings specific to linux, keymap has
keycodes which is linux specific. Hence, linux,keymap looks
appropriate. But num rows/ cols are keyboard specific, so I am not
sure if linux prefix goes well here ??
>> +Optional Properties specific to linux:
>> +- linux,keypad-no-autorepeat: do no enable autorepeat feature.
>
> It's probably worth considering whether num-rows/columns should be part
> of matrix-keyboard.txt, and whether linux,keypad-no-autorepeat should be
> part of some core keyboard binding. Some of the properties in
> tegra-kbc.txt might be worth generalizing too (debounce/repeat delay,
> ghost filter)?
>
Yes, I also think that its a good idea to make some of the above
binding more generic. Though, I think "linux,keypad-no-autorepeat"
will still be a custom binding, since its totally on the platform
whether to use
autorepeat feature or not?
>> +Example:
>> +        keypad@4ae1c000{

>> +                compatible = "ti,omap4-keypad";
>> +                keypad,num-rows = <2>;
>> +                keypad,num-columns = <8>;
>> +             linux,keypad-no-autorepeat;
>> +     };

~Sourav