Re: [PATCH v2 3/3] drm/panel: Add ilitek ili9341 panel driver

[Dillon Min]

Hi Noralf

Thanks for your time to review my patch.

On Thu, 22 Jul 2021 at 01:42, Noralf Trønnes <noralf@xxxxxxxxxxx> wrote:
>
>
>
> Den 21.07.2021 09.41, skrev dillon.minfei@xxxxxxxxx:
> > From: Dillon Min <dillon.minfei@xxxxxxxxx>
> >
> > This driver combine tiny/ili9341.c mipi_dbi_interface driver
> > with mipi_dpi_interface driver, can support ili9341 with serial
> > mode or parallel rgb interface mode by register configuration.
> >
> > Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
> > Signed-off-by: Dillon Min <dillon.minfei@xxxxxxxxx>
> > ---
>
> > +static const struct of_device_id ili9341_of_match[] = {
> > +     {
> > +             .compatible = "st,sf-tc240t-9370-t",
> > +             .data = &ili9341_stm32f429_disco_data,
> > +     },
> > +     {
> > +             /* porting from tiny/ili9341.c
> > +              * for original mipi dbi compitable
> > +              */
> > +             .compatible = "adafruit,yx240qv29",
>
> I don't understand this, now there will be 2 drivers that support the
> same display?

There is no reason to create two drivers to support the same display.

To support only-dbi and dbi+dpi panel at drm/panel or drm/tiny both
fine with me.

>
> AFAICT drm/tiny/ili9341.c is just copied into this driver, is the plan
> to remove the tiny/ driver? If so I couldn't see this mentioned anywhere.

Yes, I'd like to merge the code from drm/tiny/ili9341.c to this driver
(to make a single driver to support different bus).

I have two purpose to extend the feature drm/tiny/ili9341.c

- keep compatible = "adafruit,yx240qv29", add bus mode dts bindings (panel_bus)
  to define the interface which host wants to use. such as
panel_bus="dbi" or "rgb"
  or "i80" for this case, i will add dpi code to drm/tiny/ili9341.c.

- merge tiny/ili9341.c to this driver,remove drm/tiny/ili9341.c, add
new dts compatible
  string to support other interfaces. just like what i'm doing now.

I have no idea about your plan on drm/tiny drivers, actually some of
these panels under
the diny folder can support both dbi and dbi+dpi (much faster, need
more pins). no
doubt the requirement to support dpi is always there.

What is your preference?

Thanks & Regards
Dillon

>
> Noralf.
>
> > +             .data = NULL,
> > +     },
> > +};
> > +MODULE_DEVICE_TABLE(of, ili9341_of_match);