[lkml]   [2010]   [Aug]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 3/3] hid: 3m: Correct touchscreen emulation
On 08/28/2010 05:56 PM, Stéphane Chatty wrote:

> Le 28 août 10 à 16:29, Henrik Rydberg a écrit :
>> The current code sometimes misses to report the last BTN_TOUCH event
>> when multiple fingers are lifted simultaneously. With the
>> introduction of MT slots, the tracking id is available to determine
>> the oldest active contact.
> Hi Henrik,
> good job on exploiting the sync quirk!
> About the oldest active contact, I'm not so sure though. I don't have the device
> with me but I remember that 3M recycle IDs, giving the lowest available ID to
> any new finger; this means that the lowest ID is not always the oldest finger.

Hi Stéphane,

I think we use the term tracking id differently here. The HID_DG_CONTACTID is
actually the slot id, and the tracking id is a sequential number, increased
whenever the touch is new. I believe the patchset works correctly as long as
there is less than 32768 new touches before releasing the oldest one. :-)

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2010-08-28 18:11    [W:0.190 / U:2.748 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site