Re: 答复: 答复: 答复: [PATCH] input: alps-fix the issue alps cs19 trackstick do not work.

["dmitry.torokhov@gmail.com" <dmitry.torokhov@gmail.com>]

On Tue, Jun 11, 2019 at 09:23:33AM +0200, Pali Rohár wrote:
> On Tuesday 11 June 2019 12:32:33 Hui Wang wrote:
> > On 2019/6/11 上午11:23, Hui Wang wrote:
> > > On 2019/6/11 上午11:05, Xiaoxiao Liu wrote:
> > > > Hi Pali,
> > > > 
> > > > I discussed with our FW team about this problem.
> > > > We think the V8 method means a touchpad feature  and does not fit
> > > > the CS19 trackpoint device.
> > > > CS19 TrackPoint needn't  use any Absolute (Raw) mode and is usually
> > > > use standard mouse data.
> > > > CS19 TrackPoint device is a completely different device with
> > > > DualPoint device of Dell/HP.
> > > > CS19 TrackPoint device is independent  of Touchpad. (Touchpad is
> > > > connecting by I2C, TrackPoint is directly connecting with PS2 port.)
> > > > And it has completely another FW.
> > > > 
> > > > So we think it is better to use the mouse mode for CS19 trackpoint.
> > > 
> > > Maybe here is some mis-understanding,  the mouse mode here doesn't mean
> > > we use psmouse-base.c for cs19 (bare ps/2 mouse), we plan to use
> > > trackpoint.c to drive this HW, so this trackpoint has all features a
> > > trackpoint should have.
> > > 
> > And I sent a patch one month ago to let the the trackpoint.c to drive this
> > HW: https://www.spinics.net/lists/linux-input/msg61341.html, maybe that
> > patch is reference.
> 
> So instead of creating blacklist, you should check for TP_VARIANT_ALPS
> in alps.c and disallow its usage.
> 
> Or maybe better, move trackpoint.c detect code before alsp.c detect code
> in psmouse-base. And no changes in alps.c are needed.

I'd be very cautions of moving around the protocol detection. It is very
fragile, so if we can detect trackpoint-only case in alps.c and skip on
to trackpoint I would prefer it.

Thanks.

-- 
Dmitry