Re: [RFC PATCH 2/9] drm: bridge: Add Samsung SEC MIPI DSIM bridge driver

From: Laurent Pinchart
Date: Thu Jun 24 2021 - 08:47:12 EST


On Thu, Jun 24, 2021 at 06:02:36PM +0530, Jagan Teki wrote:
> Hi Laurent,
>
> On Thu, Jun 24, 2021 at 5:48 PM Laurent Pinchart
> <laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
> >
> > Hi Jagan,
> >
> > On Thu, Jun 24, 2021 at 05:42:43PM +0530, Jagan Teki wrote:
> > > On Thu, Jun 24, 2021 at 8:18 AM Fabio Estevam wrote:
> > > > On Wed, Jun 23, 2021 at 7:23 PM Laurent Pinchart wrote:
> > > >
> > > > > Looking at the register set, it seems to match the Exynos 5433,
> > > > > supported by drivers/gpu/drm/exynos/exynos_drm_dsi.c. Can we leverage
> > > > > that driver instead of adding a new one for the same IP core ?
> > > >
> > > > Yes. there was an attempt from Michael in this direction:
> > > > https://patchwork.kernel.org/project/dri-devel/cover/20200911135413.3654800-1-m.tretter@xxxxxxxxxxxxxx/
> > >
> > > Thanks for the reference, I will check it out and see I can send any
> > > updated versions wrt my i.MX8MM platform.
> >
> > Thanks.
> >
> > I had a brief look at the exynos driver, and I think it should be turned
> > into a DRM bridge as part of this rework to be used with the i.MX8MM.
> >
> > Is there someone from Samsung who could assist, at least to test the
> > changes ?
>
> I have hardware to verify it on i.MX8MM but from exynos I don't have
> any contact from Samsung to suggest or test. Maybe I can add Tomasz
> Figa while sending the changes?

Tomasz hasn't been working for Samsung for a loooong time (I've dropped
his Samsung address from the CC list for this reason).

> I understand that there are 2 key implementations.
>
> 1. Adjust the exynos_drm_dsi.c by dropping component_ops as i.MX8MM
> flow with LCDIF doesn't have component_ops (make sure it works with
> exynos platform first)

I think it should be turned into a real drm_bridge, it's currently
implemented based on drm_encoder.

> 2. Sec DSIM Bridge driver common cross Exynos and i.MX8MM platform
> drivers or only one Sec DSIM bridge driver to handle both the
> platforms by differentiating compatible and driver data
>
> Any more suggestions would be appreciated?

--
Regards,

Laurent Pinchart