Re: [PATCH 1/2] input: mt: Support separate contact and finger count reports

Re: [PATCH 1/2] input: mt: Support separate contact and finger count reports

[Dmitry Torokhov]

On Sat, Dec 11, 2010 at 11:28:27AM +0100, Henrik Rydberg wrote:
> A number of old and semi-recent touch devices are capable of counting
> the number of fingers on the pad within being able to give details for
> all individual contacts. This patch simplifies reporting for such
> hardware by providing a separate function for finger count.
> 

Looks good, just a couple nits below.

>  
>  /**
> + * input_mt_report_finger_count() - report contact count via buttons

"via buttons" is awkward, I'd simply dropped it,

> + * @dev: input device with allocated MT slots
> + * @count: the number of contacts
> + *
> + * Reports the contact count via BTN_TOOL_FINGER, BTN_TOOL_DOUBLETAP,
> + * BTN_TOOL_TRIPLETAP and BTN_TOOL_QUADTAP.
> + *
> + * The input core ensures only the KEY axes already setup for

s/axes/events/ ?

-- 
Dmitry

Re: [PATCH 2/2] input: mt: Add button support for five fingers

[Dmitry Torokhov]

On Sat, Dec 11, 2010 at 11:28:28AM +0100, Henrik Rydberg wrote:
> This patch adds BTN_TOOL_QUINTAP to be used by hardware reporting
> finger counts different from the number of MT contacts.

I must say this is quite ugly, but so is introducing ABS_CONTACT_COUNT
or similar, except that the latter is more extensible so if
manufacturers decide to report 6, 7, 8 fingers (but not their
coordinates) we won't have to breed BTN_TOOL_xxxTAPs...

But let me ask you this: do we know what to do with 5 fingers? How do we
plan to react to such gestures? Maybe the best option is simply ignore
it and don't report anything if there are no userspace consumers?

Thanks.

-- 
Dmitry

Re: [PATCH 2/2] input: mt: Add button support for five fingers

[Henrik Rydberg]

On 12/13/2010 03:50 AM, Dmitry Torokhov wrote:

> On Sat, Dec 11, 2010 at 11:28:28AM +0100, Henrik Rydberg wrote:
>> This patch adds BTN_TOOL_QUINTAP to be used by hardware reporting
>> finger counts different from the number of MT contacts.
> 
> I must say this is quite ugly, but so is introducing ABS_CONTACT_COUNT
> or similar, except that the latter is more extensible so if
> manufacturers decide to report 6, 7, 8 fingers (but not their
> coordinates) we won't have to breed BTN_TOOL_xxxTAPs...
> 
> But let me ask you this: do we know what to do with 5 fingers? How do we
> plan to react to such gestures? Maybe the best option is simply ignore
> it and don't report anything if there are no userspace consumers?


I agree - let's put the bar at four fingers for special solutions. Dropped.

Thanks,
Henrik