Re: [PATCH v4 00/24] drm/bridge: Make panel and bridge probe order consistent

From: John Stultz
Date: Wed Sep 29 2021 - 22:31:01 EST


On Wed, Sep 29, 2021 at 4:20 PM Rob Clark <robdclark@xxxxxxxxx> wrote:
> On Wed, Sep 29, 2021 at 2:51 PM John Stultz <john.stultz@xxxxxxxxxx> wrote:
> > On Wed, Sep 29, 2021 at 2:32 PM John Stultz <john.stultz@xxxxxxxxxx> wrote:
> > > On Wed, Sep 29, 2021 at 2:27 PM John Stultz <john.stultz@xxxxxxxxxx> wrote:
> > > > On Fri, Sep 10, 2021 at 3:12 AM Maxime Ripard <maxime@xxxxxxxxxx> wrote:
> > > > > The best practice to avoid those issues is to register its functions only after
> > > > > all its dependencies are live. We also shouldn't wait any longer than we should
> > > > > to play nice with the other components that are waiting for us, so in our case
> > > > > that would mean moving the DSI device registration to the bridge probe.
> > > > >
> > > > > I also had a look at all the DSI hosts, and it seems that exynos, kirin and msm
> > > > > would be affected by this and wouldn't probe anymore after those changes.
> > > > > Exynos and kirin seems to be simple enough for a mechanical change (that still
> > > > > requires to be tested), but the changes in msm seemed to be far more important
> > > > > and I wasn't confortable doing them.
> > > >
> > > >
> > > > Hey Maxime,
> > > > Sorry for taking so long to get to this, but now that plumbers is
> > > > over I've had a chance to check it out on kirin
> > > >
> > > > Rob Clark pointed me to his branch with some fixups here:
> > > > https://gitlab.freedesktop.org/robclark/msm/-/commits/for-mripard/bridge-rework
> > > >
> > > > But trying to boot hikey with that, I see the following loop indefinitely:
> > > > [ 4.632132] adv7511 2-0039: supply avdd not found, using dummy regulator
> > > > [ 4.638961] adv7511 2-0039: supply dvdd not found, using dummy regulator
> > > > [ 4.645741] adv7511 2-0039: supply pvdd not found, using dummy regulator
> > > > [ 4.652483] adv7511 2-0039: supply a2vdd not found, using dummy regulator
> > > > [ 4.659342] adv7511 2-0039: supply v3p3 not found, using dummy regulator
> > > > [ 4.666086] adv7511 2-0039: supply v1p2 not found, using dummy regulator
> > > > [ 4.681898] adv7511 2-0039: failed to find dsi host
> > >
> > > I just realized Rob's tree is missing the kirin patch. My apologies!
> > > I'll retest and let you know.
> >
> > Ok, just retested including the kirin patch and unfortunately I'm
> > still seeing the same thing. :(
> >
> > Will dig a bit and let you know when I find more.
>
> Did you have a chance to test it on anything using drm/msm with DSI
> panels? That would at least confirm that I didn't miss anything in
> the drm/msm patch to swap the dsi-host vs bridge ordering..

Not a dsi panel, but for what it's worth, I did just test the series
with the db845c w/ HDMI using the lt9611 bridge.
So at least that is looking ok.

thanks
-john