Upcoming Kernel - MultiTouchScreen Support

[Luis R. Rodriguez]

On Thu, Mar 4, 2010 at 12:18 AM, Amit Kucheria
<amit.kucheria at canonical.com> wrote:
> Hi Thomas,
>
> I'm forwarding this to the kernel-team mailing list so other developers can
> also comment.
>
> Regards,
> Amit
>
> ----- Forwarded message from Thomas Winteler <info at win-soft.ch> -----
>
> Date: Wed, 03 Mar 2010 09:26:56 +0100
> From: Thomas Winteler <info at win-soft.ch>
> To: amit.kucheria at ubuntu.com
> Subject: Upcoming Kernel - MultiTouchScreen Support
> User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.9.1.8) Gecko/20100216 Thunderbird/3.0.2
> Organization: Win-Soft, Business IT eXpert
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Good Morning Mr. Amit Kucheria
>
> Thank you for your time, reading my eMail.
>
> The new Hardware on the market offer MultiTouchScreens, like the Netbook
> from ASUS:
> ASUS EEE PC T91MT
> http://www.asus.com/product.aspx?P_ID=KIqtSJ1aVsmVpeqS
>
> I found some information in ASUS's Support Forum and found also a Linux
> Driver Builder.
> http://vip.asus.com/forum/view.aspx?id=20091214162901203&SLanguage=en-us&page=2&board_id=20&model=Eee%20PC%20T91MT
>
> ENAC Interactive computing laboratory HowTo
> http://lii-enac.fr/en/projects/shareit/linux-howto.html
>
> Drivers from ENAC
> http://lii-enac.fr/en/projects/shareit/linux.html
>
> MosArt MT Driver for ASUS's T91MT
> http://lii-enac.fr/en/projects/shareit/multitouch-devices.html
> - --> MosArt
>
> The Problem on this thing is, that the Kernel needs to be patched and
> recompiled to get it running.

The kernel changes don't seem that bad, I only see mention to one
header file which needs to be changed as follows:

diff --git a/include/linux/hid.h b/include/linux/hid.h
index b1344ec..5ad8e6e 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -663,7 +663,7 @@ struct hid_ll_driver {

 /* Applications from HID Usage Tables 4/8/99 Version 1.1 */
 /* We ignore a few input applications that are not widely used */
-#define IS_INPUT_APPLICATION(a) (((a >= 0x00010000) && (a <=
0x00010008)) || (a == 0x00010080) || (a == 0x000c0001) || ((a >=
0x000d0002) && (a <= 0x000d000
+#define IS_INPUT_APPLICATION(a) (a >= 0xd0002 && a <= 0xd0006)

 /* HID core API */

But this the change required is not documented, why is this required?
Anyway apart from it seems you need to modify the hid module and
provide it as a replacement. The rest is just adding drivers, and that
should be relatively trivial.

What would be better is to track what is not upstream, see if the
authors are working on that, and if not see if the driver project can
get it upstream at least through staging.

  Luis