[PATCH 2/2] drm/bridge: lt9611: Do not generate HFP/HBP/HSA and EOT packet

[Dmitry Baryshkov]

[Adding freedreno@ to cc list]

On Wed, 5 Jul 2023 at 08:31, Jagan Teki <jagan at amarulasolutions.com> wrote:
>
> Hi Amit,
>
> On Wed, Jul 5, 2023 at 10:15 AM Amit Pundir <amit.pundir at linaro.org> wrote:
> >
> > Hi Marek,
> >
> > On Wed, 5 Jul 2023 at 01:48, Marek Vasut <marex at denx.de> wrote:
> > >
> > > Do not generate the HS front and back porch gaps, the HSA gap and
> > > EOT packet, as these packets are not required. This makes the bridge
> > > work with Samsung DSIM on i.MX8MM and i.MX8MP.
> >
> > This patch broke display on Dragonboard 845c (SDM845) devboard running
> > AOSP. This is what I see
> > https://people.linaro.org/~amit.pundir/db845c-userdebug/v6.5-broken-display/PXL_20230704_150156326.jpg.
> > Reverting this patch fixes this regression for me.
>
> Might be msm dsi host require proper handling on these updated
> mode_flags? did they?

The msm DSI host supports those flags. Also, I'd like to point out
that the patch didn't change the rest of the driver code. So even if
drm/msm ignored some of the flags, it should not have caused the
issue. Most likely the issue is on the lt9611 side. I's suspect that
additional programming is required to make it work with these flags.

-- 
With best wishes
Dmitry