linux-kernel - Re: [PATCH 1/4] hid-multitouch: Auto detection of maxcontacts

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <AANLkTin4KsPWRfFEEYXkjWdnEnXyiMyDGc6eEWFA_kWx@mail.gmail.com>
Date:	Wed, 9 Mar 2011 10:03:45 +0100
From:	Benjamin Tissoires <benjamin.tissoires@...c.fr>
To:	Henrik Rydberg <rydberg@...omail.se>
Cc:	Dmitry Torokhov <dmitry.torokhov@...il.com>,
	Jiri Kosina <jkosina@...e.cz>,
	Stephane Chatty <chatty@...-enac.fr>,
	linux-input@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/4] hid-multitouch: Auto detection of maxcontacts

On Wed, Mar 9, 2011 at 09:42, Henrik Rydberg <rydberg@...omail.se> wrote:
> Hi Benjamin,
>
>> This patch enables support of autodetection of maxcontacts.
>> We can still manually provide maxcontact in case the device
>> lies on it.
>>
>> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@...c.fr>
>
> It seems quite alright to let the classes contain the expected number
> of contacts, so I do not really see the reason for that part of the
> patch. How about keeping the maxcontacts in the class, and then do
> max(hid-provided-maxcontacts, default-maxcontacts)?
>

Yep, I've got three particular reasons:
- 3M: there are two devices now, 1968 and 2256. The first one is a 10
touches only, whereas the second one is a 60 touches.
- autodetection of multitouch devices. I have some patches on my tree
(that we do not want to go upstream right now for some reasons) that
allows us to plug any unknown multitouch devices and to let
hid-multitouch handling it. As most of the devices are 2 touches only,
and as the generic way to work with a multitouch devices is to iterate
over all the slots, using 10 touches by default infers a lot of
instructions that can be avoided.
- finally, it simplifies the writing of the new CLS (we just need to
know how the device works to add the right quirks).

Cheers,
Benjamin
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/