Re: [PATCH 2/5] HID: hid-multitouch: get maxcontacts also fromlogical_max value

From: Henrik Rydberg
Date: Wed May 09 2012 - 15:41:11 EST

Hi Benjamin,

> >> Win8 devices are required to present the feature "Maximum Contact Number".
> >> If the current value is 0, then, the driver can get the actual supported
> >> contact count by seeing the logical_max.
> >
> > And for win7, it is zero?
> Well, the truth is that the Win8 specification formally describes the
> values here. And to get the certification, hardware makers have to put
> the right value in logical_max.
> TBH, I don't care that much now with win7 devices. Most of them are a
> piece of crap (not true dual fingers, problems in hid reports
> descriptors, etc...), but they just work (we made the necessary
> things). With the introduction of Win8, hardware makers will have to
> *certify* their devices, and thus, the Win8 driver is much less
> tolerant. I really think that we are going to see more and more win8
> devices, whereas win7 devices will fade out.
> I had to add this patch because I have a win8 device that has the
> value associated to this field at 0, and it's the first I saw with
> this behavior.

As long as all existing devices are unaffected, it's fine, hence the question.

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