Re: [PATCH 4.4 093/113] pinctrl: msm: Really mask level interrupts to prevent latching

[Greg KH]

On Wed, Oct 10, 2018 at 02:12:01PM +0200, Linus Walleij wrote:
> On Wed, Oct 10, 2018 at 9:53 AM Nathan Chancellor
> <natechancellor@xxxxxxxxx> wrote:
> > On Wed, Oct 10, 2018 at 09:12:58AM +0200, Linus Walleij wrote:
> > > On Tue, Oct 9, 2018 at 8:33 AM Nathan Chancellor
> > > <natechancellor@xxxxxxxxx> wrote:
> > >
> > > > Sigh, sorry, I caught this after I sent my initial all good email but
> > > > this commit breaks NFC on my Pixel 2 XL (toggle becomes greyed out and
> > > > apps that want to use it ask to enable it). I can't say why, I'm more
> > > > than happy to debug but I'm assuming it's some voodoo that Qualcomm has
> > > > done out of tree. I'll leave it up to you how to proceed given that I
> > > > can't run mainline :(
> > >
> > > Which NFC driver is this?
> > > Just want to make sure it looks sane.
> > >
> > > Yours,
> > > Linus Walleij
> >
> > Hi Linus and Bjorn,
> >
> > These two files should be it I believe:
> > https://android.googlesource.com/kernel/msm/+/android-9.0.0_r0.22/drivers/nfc/nq-nci.c
> > https://android.googlesource.com/kernel/msm/+/android-9.0.0_r0.22/drivers/nfc/ese/pn81a.c
> >
> > Sorry I didn't get around to digging into this further today, I will try
> > to get to it in the morning.
> 
> I'm confused. These are not in the mainline kernel and presumably
> not in the stable kernel either.
> 
> So when you say "this commit breaks NFC on my Pixel 2 XL" you
> mean that when you apply this commit to the android msm kernel,
> which has a few other stable fixes backported, it breaks?

If these drivers are obviously broken, I have no objection to merging
patches like this and telling qcom to fix their code.  But if the issue
is more subtle, like change in behavior that is unanticipated, then I am
a bit more reluctant to take patches that break working systems.

It would be nice to figure out what is going wrong here as I think the
drivers above are being submitted upstream right now, correct?

thanks,

greg k-h