Re: [PATCH] Revert "Input: clear BTN_RIGHT/MIDDLE on buttonpads"

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Wed, Mar 30, 2022 at 02:30:37PM +0200, Benjamin Tissoires wrote:
> On Wed, Mar 30, 2022 at 2:27 PM Thorsten Leemhuis
> <regressions@leemhuis.info> wrote:
> >
> > Hi, this is your Linux kernel regression tracker.
> >
> > On 21.03.22 19:44, José Expósito wrote:
> > > This reverts commit 37ef4c19b4c659926ce65a7ac709ceaefb211c40.
> > >
> > > The touchpad present in the Dell Precision 7550 and 7750 laptops
> > > reports a HID_DG_BUTTONTYPE of type MT_BUTTONTYPE_CLICKPAD. However,
> > > the device is not a clickpad, it is a touchpad with physical buttons.
> > >
> > > In order to fix this issue, a quirk for the device was introduced in
> > > libinput [1] [2] to disable the INPUT_PROP_BUTTONPAD property:
> > >
> > >       [Precision 7x50 Touchpad]
> > >       MatchBus=i2c
> > >       MatchUdevType=touchpad
> > >       MatchDMIModalias=dmi:*svnDellInc.:pnPrecision7?50*
> > >       AttrInputPropDisable=INPUT_PROP_BUTTONPAD
> > >
> > > However, because of the change introduced in 37ef4c19b4 ("Input: clear
> > > BTN_RIGHT/MIDDLE on buttonpads") the BTN_RIGHT key bit is not mapped
> > > anymore breaking the device right click button and making impossible to
> > > workaround it in user space.
> > >
> > > In order to avoid breakage on other present or future devices, revert
> > > the patch causing the issue.
> > >
> > > Cc: stable@vger.kernel.org
> > > Link: https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/481 [1]
> > > Link: https://bugzilla.redhat.com/show_bug.cgi?id=1868789  [2]
> > > Signed-off-by: José Expósito <jose.exposito89@gmail.com>
> > > [...]
> >
> > Jiri, Benjamin, what the status here? Sure, this is not a crucial
> > regression and we are in the middle of the merge window, but it looks
> > like nothing has happened for a week now. Or was progress made somewhere
> > and I just missed it?
> 
> No, I think it just wasn't picked up by the input maintainer yet
> (Dmitry, now in CC).
> 
> FWIW:
> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
> 
> José, please do not forget to add the input maintainer when you target
> the input tree, not the HID one :)

I see that there were several ACKs, but how many devices misuse the
HID_DG_BUTTONTYPE? Would it be better to quirk against either affected
Dell models, or particular touchpads (by HID IDs) instead of reverting
wholesale?

Thanks.

-- 
Dmitry