From mboxrd@z Thu Jan  1 00:00:00 1970
From: Henrik Rydberg <rydberg@euromail.se>
Subject: Re: [PATCH 2/2] elantech: Report multitouch with proper ABS_MT messages
Date: Wed, 05 May 2010 20:01:45 +0200
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References: <4BE1629E.50901@tudelft.nl> <20100505163832.GA7337@core.coreip.homeip.net>
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To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: =?ISO-8859-1?Q?=C9ric_Piel?= <E.A.B.Piel@tudelft.nl>, Florian Ragwitz <rafl@debian.org>, "linux-input@vger.kernel.org" <linux-input@vger.kernel.org>

Dmitry Torokhov wrote:
>> @@ -253,7 +253,6 @@ static void elantech_report_absolute_v2(struct psmouse *psmouse)
>>  
>>  	/* byte 0: n1  n0   .   .   .   .   R   L */
>>  	fingers = (packet[0] & 0xc0) >> 6;
>> -	input_report_key(dev, BTN_TOUCH, fingers != 0);
> 
> Mousedev works a tad better if BTN_TOUCH is reported first. Otherwise
> looks good.
> 
> Henrik, should we report "tool width" as ABS_MT_WIDTH_MAJOR?

I might be missing some context here, I see no prior use of width in the driver.
The answer is either ABS_MT_TOUCH_MAJOR or ABS_MT_WIDTH_MAJOR depending on how
the width is actually computed. Generally, it makes little sense to have
ABS_MT_WIDTH_MAJOR (width of approaching finger) without ABS_MT_TOUCH_MAJOR
(width of touching finger), but it is ok to have only ABS_MT_TOUCH_MAJOR. Things
like thumb detection requires both values to be reliable.

Henrik