Re: [PATCH v3 1/1] drm: bridge: ti-sn65dsi83: Fix DSI mode flags for stable LVDS output

[Ernest Van Hoecke]

Hi Francesco,
Hi Luca,

On Sat, Oct 24, 2026 at 11:54:05AM +0200, Francesco Dolcini wrote:
> Hello Luca, Ernest,
> 
> On Wed, Sep 09, 2026 at 03:30:53PM +0200, Luca Ceresoli wrote:
> > On Fri Sep 4, 2026 at 2:02 PM CEST, Ernest Van Hoecke wrote:
> > >> > Also, from our testing, when using:
> > >> >
> > >> > dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
> > >> >           MIPI_DSI_MODE_VIDEO_NO_HSA | MIPI_DSI_MODE_NO_EOT_PACKET;
> > >> >
> > >> > we are not able to get display output.
> > >>
> > >> This is the case for the panel I worked on as well. In the practice we both
> > >> observe that non-burst mode is what fixes the panel, but there is no clear
> > >> explanation of the reason in the docs (that's what I hope to discover from
> > >> TI).
> > >>
> > > I am testing a DSI panel on our Verdin iMX8MP module, and noticed that
> > > this caused a regression.
> 
> [...]
> 
> > > I think we'll need to either revert this and later apply both together
> > > when ready, or apply the second patch now as well. Right now, it broke
> > > the DSI panel behind a TI sn65dsi83 bridge on v7.3-rc1.
> > 
> > Reverting is surely the last resort. If you can answer the above questions
> > it would be good, maybe we find out reverting is not necessary, and worst
> > case we'll revert with better understanding on what went wrong, and maybe
> > come up with a new fix that doesn't regress.
> 
> What's the status of this regression?
> 
> Francesco
> 

I still need to test and look into this, that will happen either in
December as I'm off in November, or by someone else in the team. Sorry
for the delay.

Kind regards,
Ernest