Re: [PATCH v4 3/3] drm/panel-fannal-c3004: Add fannal c3004 DSI panel

[Marek Vasut]

On 7/12/23 17:10, Paulo Pavacic wrote:

Hi,

[...]

> > > > Or whether it makes sense to outright have a separate driver. The later
> > > > would introduce duplication, but maybe that much duplication is OK.
> > >
> > > I would like to create new driver because panel-st7701 seems to be
> > > outdated and is using non-standard macro (ST7701_WRITE()
> >
> > There is no such macro:
> >
> > $ git grep ST7701_WRITE drivers/gpu/drm/panel/ | wc -l
> > 0
> >
> > There never was such a macro used in the driver either, are you sure you
> > are not using some hacked up patched downstream fork of the driver ?
>
> I meant ST7701_DSI() macro; It can be replaced with
> mipi_dsi_generic_write_seq from kernel 6.3. Sorry for the confusion.

OK

> > $ git log -p next/master --
> > drivers/gpu/drm/panel/panel-sitronix-st7701.c | grep ST7701_WRITE | wc -l
> > 0
> >
> > > ) and for me
> > > it is crashing kernel 5.15.
> >
> > Have you based all the aforementioned discussion and argumentation on
> > year and half old Linux 5.15.y code base too ?
> >
> > If so, you are missing many patches:
> >
> > $ git log --oneline --no-merges v5.15..next/master --
> > drivers/gpu/drm/panel/panel-sitronix-st7701.c
> > 5a2854e577dc2 drm: panel: Add orientation support for st7701
> > e89838968ee44 drm: panel: Add Elida KD50T048A to Sitronix ST7701 driver
> > c62102165dd79 drm/panel/panel-sitronix-st7701: Remove panel on DSI
> > attach failure
> > 49ee766b364ed drm/panel/panel-sitronix-st7701: Clean up CMDnBKx selection
> > c1cdee9b685a1 drm/panel/panel-sitronix-st7701: Fix RTNI calculation
> > 57b2efce45ef5 drm/panel/panel-sitronix-st7701: Add Densitron
> > DMT028VGHMCMI-1A TFT
> > 42542c7904cf2 drm/panel/panel-sitronix-st7701: Split GIP and init sequences
> > 83b7a8e7e88e7 drm/panel/panel-sitronix-st7701: Parametrize voltage and
> > timing
> > de2b4917843cd drm/panel/panel-sitronix-st7701: Infer horizontal pixel
> > count from TFT mode
> > 82f9cee25598a drm/panel/panel-sitronix-st7701: Adjust porch control
> > bitfield name
> > 1ba85119afb5e drm/panel/panel-sitronix-st7701: Infer vertical line count
> > from TFT mode
> > 779c84fea3dbd drm/panel/panel-sitronix-st7701: Make gamma correction TFT
> > specific
> > 7fa8e07128ed6 drm/panel/panel-sitronix-st7701: Make voltage supplies
> > common to ST7701
> > a6c225be3da7e drm/panel/panel-sitronix-st7701: Enable DSI burst mode,
> > LPM, non-continuous clock
> > 6f481afe220d3 drm/panel/panel-sitronix-st7701: Make DSI mode flags
> > common to ST7701
> > 79abca2b39900 drm/mipi-dsi: Make remove callback return void
>
> I will try backporting those patches to 5.15 and applying them to see
> whether it will then work with initialization sequences provided in
> this merge request just to be sure not to have duplication. We are
> still working on transitioning to newer kernel so for the time being
> I'm using mostly 5.15.
>
> On 5.15 kernel I have following kernel panic only with st7701 from the
> panel drivers I have tried:
>
> [   20.255322] Kernel panic - not syncing: Asynchronous SError Interrupt
> [   20.255326] CPU: 1 PID: 36 Comm: kworker/1:1 Tainted: G           O
>       5.15.77-5.15.77-2.1.0 #1

The latest 5.15.y is 5.15.120 , can you re-test on that version ?

> [   20.255330] Hardware name: XXX i.MX8XX board:XXX (DT)

Is this some NXP downstream kernel fork with thousands of extra patches?
The version string 2.1.0 looks very much like NXP versioning scheme ...

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