Re: [RFC v2 03/10] hid-multitouch: support for PixCir-based panels

From: Benjamin Tissoires
Date: Fri Jan 07 2011 - 12:08:01 EST

On Fri, Jan 7, 2011 at 4:57 PM, Henrik Rydberg <rydberg@xxxxxxxxxxx> wrote:
> On Fri, Jan 07, 2011 at 04:12:24PM +0100, Benjamin Tissoires wrote:
>> Hi Henrik,
>> I've made the changes and I pushed them on the git of our lab. I
>> thought it was easier for you to have a look at the changes instead of
>> resending the whole patch. But v3 will be for this afternoon.
> Well, it is not really easier, since there is no easy way to comment
> on the code. Also, transparency is lost. Please let the review process
> take its time.
>> the repo is at:
>> the changes are on the branch "hid-multitouch-dtor" from "Copyright
>> notice" to the head ("hid-input: better way of handling
>> To summarize:
>> - I used touch_state and seen_in_this_frame -> I hope the semantic is
>> now clearer. I was able to test it on stantum and cypress device. I
>> should do the test for pixcir as soon as I can have some time in the
>> afternoon, and the test against generaltouch should happend in the
>> beginning of the week.
> The code looks clearer, but there are still two more or less identical
> structures in there. Please remove, it just looks silly.

In not a big fan of this idea, but we have to find a compromise -> will do.

>> - I integrated fuzz (please check)
> But the mt_input_mapped function did not change - needs to change too.

I can not see any differences between mt_input_mapped and those found
in 3m and egalax. Can you point me exactly what I should add please?

>> - I re-factorized set_abs (just copied-pasted your code)
> Ok.
>> - I made other small changes
>> - Concerning the quirks, I am not very in favor ATM: a flag for
>> compute slot will infer a switch of 5 cases in the emit_event, and the
>> idea was to be able to have a constant time access (1) when using
>> specific function.
>> The Quirk MT_QUIRK_NOT_SEEN_MEANS_UP is better (it will speed up a
>> little the code: 1 test against 1 test and 1 affectation) but I don't
>> think it worse the effort for further device additions.
> Given everything that happens within a hid packet, this really, really
> does not matter much. And the quirks can be implemented efficiently
> too, if really needed.

Will do.

>> - The Egalax problem: I am pretty sure that Stéphane took this driver
>> into account when writing the original patch. BTW I propose to
>> postpone the problem for 2.6.39.
> This driver is aiming at engulfing a larger set of drivers, and as
> such, should be prepared sensibly, IMO. Rushing things will only cause
> us grief further down the road.

So, have you got any clue (or even better, can you test a solution)
for those devices?

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