linux-kernel - Re: [PATCH 2/3] input: touchscreen: of: Register multitouch axes

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: <20141106160621.GM2989@lukather>
Date:	Thu, 6 Nov 2014 17:06:21 +0100
From:	Maxime Ripard <maxime.ripard@...e-electrons.com>
To:	Dmitry Torokhov <dmitry.torokhov@...il.com>
Cc:	Lothar Waßmann <LW@...O-electronics.de>,
	Henrik Rydberg <rydberg@...omail.se>,
	linux-input@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/3] input: touchscreen: of: Register multitouch axes

Hi,

On Wed, Nov 05, 2014 at 09:56:35AM -0800, Dmitry Torokhov wrote:
> On Wed, Nov 05, 2014 at 04:07:49PM +0100, Maxime Ripard wrote:
> > So far, the DT parsing code was only setting up the regular input axes,
> > completely ignoring their multitouch counter parts.
> > 
> > Fill them with the same parameters than the regular axes.
> > 
> > Signed-off-by: Maxime Ripard <maxime.ripard@...e-electrons.com>
> > ---
> >  drivers/input/touchscreen/of_touchscreen.c | 12 +++++++++---
> >  1 file changed, 9 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/input/touchscreen/of_touchscreen.c b/drivers/input/touchscreen/of_touchscreen.c
> > index 74d6b0eb50ac..cf2a753edd96 100644
> > --- a/drivers/input/touchscreen/of_touchscreen.c
> > +++ b/drivers/input/touchscreen/of_touchscreen.c
> > @@ -42,17 +42,23 @@ void touchscreen_parse_of_params(struct input_dev *dev)
> >  
> >  	maximum = of_get_optional_u32(np, "touchscreen-size-x");
> >  	fuzz = of_get_optional_u32(np, "touchscreen-fuzz-x");
> > -	if (maximum || fuzz)
> > +	if (maximum || fuzz) {
> >  		input_set_abs_params(dev, ABS_X, 0, maximum, fuzz, 0);
> > +		input_set_abs_params(dev, ABS_MT_POSITION_X, 0, maximum, fuzz, 0);
> 
> Not all devices are multitouch so you shoudl not be setting multitouch
> bits unconditionally.

Hmmm, right.

> In I think we should rely on driver to set capability bits properly and
> then here test them and apply the readings. Probably also issue a
> warning if we see max/fuzz setting but neither ABS_<N>/ABS_MT_<N>
> capabilities.

What I was aiming at was to avoid DT parsing duplication for the
!multitouch and multitouch axis. I don't think there's a way to copy
the parameters.

The mt_init_slots might be a solution, but it does the copy the other
way around: from the multitouch to the !multitouch axis, and without
enabling it, which renders using both input_mt_init_slots and the
of_touchscreen code together impossible.

Is there a way to just enable an axis without calling
input_set_abs_params? Is __set_bit enough?

Thanks,
Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)