Re: [PATCH] extcon: arizona: Implement button detection support

[Chanwoo Choi <cw00.choi@samsung.com>]

On 07/25/2012 08:11 PM, Mark Brown wrote:

>> Why do you should report released event to all of buttons? I think that
>> you should only
>> report released event to previous pressed button. If user press two
>> button on the headset
>> at the same time and then user release only one button with pressed
>> another button, extcon-arizona driver have to report released event to
>> previous pressed button except for still pressed another button.
> 
> The input API already supresses duplicate reports, they won't be
> propagated to userspace, so there's no point in duplicating the work
> to remember what buttons are pressed in individual drivers.  Userspace
> will only see events reported that refect changes in state.


The extcon-arizona include six buttons(BTN_0, BTN_1, BTN_2, BTN_3,
BTN_4, BTN_5). Currently, extcon-arizona driver will report released
event to all buttons (BTN_0, BTN_1, BTN_2, BTN_3, BTN_4, BTN_5)
when released event irrespective of the type of buttons is happened.

If user press BTN_0 and BTN_1 at the same time and then user only
released BTN_0 but BTN_1 is still pressed, is it right that report
released event to all of buttons? I think that different event between
BTN_0 and BTN_1.

Thank you,
Chanwoo Choi