[PATCH 4/4] omap4-droid4: Use software debounce for gpio-keys

[pavel@ucw.cz (Pavel Machek)]

Hi!

> The default value of 5ms will use GPIO hardware based debounce clocks
> that will keep L4PER from idling consuming about extra 30mW.
> 
> Use a value of 10ms that is above the hardware debounce maximum of
> 7.95ms forcing software based debouncing.
> 
> This allows droid4 to enter PER retention during idle as long as UARTs
> are idled and USB modules unloaded or unbound.
> 
> Note that there seems to be a pending issue with having droid 4 enter core
> retention during idle where GPIO bank 1 needs to be reset late after init
> for some reason to not block core retention. In addition to that, we are
> also missing GPIO related PM runtime calls for omap4 that will be posted
> separately.

Thanks, will take a look.

BTW, did you notice that debouncing is wrong on most of the keyboard?
If you double click a key (most will do, for example "J") it will fail
to recognize second release and instead of expected "jj", you get
autorepeat ("jjjjjjjjjjjjjjjjjjjjjj...").

Ok, I guess main keyboard is not on GPIO...

Best regards,

								Pavel

> @@ -128,6 +128,7 @@
>  			gpios = <&gpio5 26 GPIO_ACTIVE_LOW>; /* gpio154 */
>  			linux,code = <KEY_VOLUMEDOWN>;
>  			linux,can-disable;
> +			debounce-interval = <10>;

I'd say this subtlety is worth a comment.

									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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