Re: [PATCH v7 01/10] drm: bridge: Add Samsung DSIM bridge driver

Jagan Teki
2022-10-18T03:06:46Z

On Mon, Oct 17, 2022 at 2:31 PM Marek Szyprowski
<m.szyprowski@samsung.com> wrote:
>
> Hi,
>
> On 17.10.2022 10:48, Marek Vasut wrote:
> > On 10/17/22 09:43, Jagan Teki wrote:
> >> On Mon, Oct 17, 2022 at 12:49 PM Marek Vasut <marex@denx.de> wrote:
> >>> On 10/17/22 04:49, Jagan Teki wrote:
> >>>> On Sun, Oct 16, 2022 at 3:16 AM Marek Vasut <marex@denx.de> wrote:
> >>>>>
> >>>>> On 10/5/22 17:13, Jagan Teki wrote:
> >>>>>> Samsung MIPI DSIM controller is common DSI IP that can be used in
> >>>>>> various
> >>>>>> SoCs like Exynos, i.MX8M Mini/Nano.
> >>>>>>
> >>>>>> In order to access this DSI controller between various platform
> >>>>>> SoCs,
> >>>>>> the ideal way to incorporate this in the drm stack is via the drm
> >>>>>> bridge
> >>>>>> driver.
> >>>>>>
> >>>>>> This patch is trying to differentiate platform-specific and
> >>>>>> bridge driver
> >>>>>> code by maintaining exynos platform glue code in exynos_drm_dsi.c
> >>>>>> driver
> >>>>>> and common bridge driver code in samsung-dsim.c providing that
> >>>>>> the new
> >>>>>> platform-specific glue should be supported in the bridge driver,
> >>>>>> unlike
> >>>>>> exynos platform drm drivers.
> >>>>>>
> >>>>>> - Add samsung_dsim_plat_data for keeping platform-specific
> >>>>>> attributes like
> >>>>>> host_ops, irq_ops, and hw_type.
> >>>>>>
> >>>>>> - Initialize the plat_data hooks for exynos platform in
> >>>>>> exynos_drm_dsi.c.
> >>>>>>
> >>>>>> - samsung_dsim_probe is the common probe call across
> >>>>>> exynos_drm_dsi.c and
> >>>>>> samsung-dsim.c.
> >>>>>>
> >>>>>> - plat_data hooks like host_ops and irq_ops are invoked during the
> >>>>>> respective bridge call chains.
> >>>>>
> >>>>> Maybe the Subject should say "Split ... driver" or "Move ...
> >>>>> driver" ,
> >>>>> since it is not adding a new driver here ?
> >>>>
> >>>> Though it is not added a completely new driver, it is adding more
> >>>> infrastructure platform code to be compatible with both Exynos and
> >>>> i.MX8M. This is the prime reason for adding that commit head and
> >>>> explaining the same in the commit body.
> >>>
> >>> Diffstat looks like this:
> >>>
> >>> drivers/gpu/drm/bridge/samsung-dsim.c | 1703
> >>> ++++++++++++++++++++++
> >>> drivers/gpu/drm/exynos/Kconfig | 1 +
> >>> drivers/gpu/drm/exynos/exynos_drm_dsi.c | 1766
> >>> ++---------------------
> >>> include/drm/bridge/samsung-dsim.h | 113 ++
> >>> 7 files changed, 1952 insertions(+), 1653 deletions(-)
> >>>
> >>> Looks to me like most of the code is just moved from existing driver in
> >>> this patch.
> >>
> >> Yeah, as I explained (from commit) it is moved, updated, and written
> >> the plat code. How about this head?
> >>
> >> "drm: bridge: Add Samsung DSIM bridge (Split from exynos_drm_dsi)"
> >
> > I disagree with the "Add" part of the Subject, but I'll wait for
> > others' opinion here.
>
> Maybe something like a "Generalize Exynos-DSI DRM driver into a generic
> Samsung DSIM bridge"?

I agreed.

Jagan.