Re: Using gpio_keys with regmapped gpio?

[Thor Thayer <tthayer-yzvPICuk2ABMcg4IHK0kFoH6Mc4MB0Vx@public.gmane.org>]

On 03/31/2015 03:17 PM, Dmitry Torokhov wrote:
> On Tue, Mar 31, 2015 at 02:57:35PM -0500, Thor Thayer wrote:
>> Hi,
>>
>> I have a SPI gpio expander chip that is using the regmap framework.
>> There are some pushbuttons that I'd like to use the gpio_keys
>> framework for but only the first button press creates an input
>> event.
>>
>> It seems like my problem occurs because I'm only getting events on a
>> button press.  The input_get_disposition() function toggles a local
>> copy of the button state [__change_bit(code, dev->key);] in the
>> input.c file. I think this function also needs to be called when the
>> button is released to toggle the dev->key state and re-arm for the
>> next button press.
>
> Yes.
>
>>
>> I tried enabling autorepeat but that causes an infinite loop in the
>> input_repeat_key() function.
>>
>> In both cases, it seems like the button press condition must be
>> cleared when the button is released. This seems like it should be
>> common for all GPIOs so I'm probably missing something.
>
> It sounds like your expander does not generate interrupt when the button
> is released and so gpio-keys driver is not aware of it.
>
> Thanks.
>

Thanks for the quick reply. Is giving an interrupt on both press and 
release a requirement for gpio-keys? or is there another setup that I'm 
not aware of?

How does the gpio-key framework work with register mapped GPIOs that are 
rising-edge or falling-edge triggered? I tend to think of these IRQ 
states as the general case for GPIO.

Thanks


--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html