Re: Problems with Elantech touchpad in 3.18-rc2

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

On Fri, Oct 31, 2014 at 06:30:40PM +0100, Pavel Machek wrote:
> On Fri 2014-10-31 09:24:36, Dmitry Torokhov wrote:
> > On Thu, Oct 30, 2014 at 12:25:06PM -0700, Dmitry Torokhov wrote:
> > > On Thu, Oct 30, 2014 at 12:06:03PM -0700, Linus Torvalds wrote:
> > > > On Thu, Oct 30, 2014 at 11:03 AM, Dmitry Torokhov
> > > > <dmitry.torokhov@gmail.com> wrote:
> > > > >
> > > > > Linus, any guidance here? Can we live with such regression?
> > > > 
> > > > No. If people are already finding machines with problems, that means
> > > > that there will be a lot of them once distributions move to that
> > > > kernel.
> > > 
> > > My only argument here is that failure is much less severe than with MUX
> > > case: when in legacy mode the worst that is happening is that advanced
> > > features (multi-touch, two-finger scroilling, etc) do not work so the
> > > experience is similar to Windows box with no venrod drivers installed.
> > > Whereas when active MUX does not work but we are tying to use it your
> > > device is completely hosed.
> > 
> > So I slept on it and I decided that we should indeed revert the patch,
> > since it causes more grief to people with good hardware than I
> > expected. We should not punish owners of good hardware because some
> > vendors can't write their firmware.
> 
> You can still add "for anything manufactured in 2015+, assume it does
> not need MUX" and add a whitelist entry for any machine with external
> ps/2 ports that still needs it... I guess there would be very little
> of them made in 2015+.

No, that Clevo W650SH that Roel has is a Haswell and is fairly recent
and has no external PS/2 ports and still wants to be in active MUX mode.
So we'll have to continue with the blacklist I'm afraid.

-- 
Dmitry