[PATCH RESEND 1/1] drm/panel: st7703: Fix Panel Initialization for Anbernic RG353V-V2

[Ao Zhong]

Hello Chris Morgan, Guido Günther,

I will post a v2 patch. I will supplement the commit information and
attach the reference links I used when modifying the init sequence.

Ao Zhong

Am Fr., 9. Feb. 2024 um 22:35 Uhr schrieb Chris Morgan
<macromorgan at hotmail.com>:
>
> On Fri, Feb 09, 2024 at 11:08:22AM +0100, Guido Günther wrote:
> > Hi Ao,
> >
> > this doesn't say why that was changed but your cover letter
> > has that information:
> >
> > > After correcting these parameters by referencing the
> > > device tree in JELOS (which uses the BSP kernel for RK3566), the panel
> > > started to work properly.
> >
> > Can you add that to the commit message and maybe add an URL as
> > reference please?
> >
> > I've added Chris to the cc: list. He submitted the original rg353v2
> > and we don't want to break other devices. Chris, do you have any means
> > to check these values?
>
> I checked. I'm not sure exactly how but when I fired up the most recent
> kernel this panel appeared to have problems with the init sequence as
> defined. After making the changes from this patch series it seems to be
> back to normal. So these changes appear to be needed for existing
> devices, and I'm not sure what could have caused the regression...
>
> Note the previous settings did still appear to work, the panel just
> took much longer to start working after the init sequence (as much
> as 20 seconds on cold boot, clearly indicating a problem).
>
> Thank you for the fix!
>
> Tested-by: Chris Morgan <macromorgan at hotmail.com>
>
> >
> > Cheers,
> >  -- Guido
> >
> > On Sun, Jan 28, 2024 at 03:10:48AM +0100, Ao Zhong wrote:
> > > This patch resolves the issue with the panel initialization of the
> > > Anbernic RG353V-V2 caused by incorrect parameters.
> > >
> > > Signed-off-by: Ao Zhong <hacc1225 at gmail.com>
> > > ---
> > >  drivers/gpu/drm/panel/panel-sitronix-st7703.c | 4 ++--
> > >  1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/panel/panel-sitronix-st7703.c b/drivers/gpu/drm/panel/panel-sitronix-st7703.c
> > > index b55bafd1a8be..a346d6c3d283 100644
> > > --- a/drivers/gpu/drm/panel/panel-sitronix-st7703.c
> > > +++ b/drivers/gpu/drm/panel/panel-sitronix-st7703.c
> > > @@ -357,8 +357,8 @@ static int rg353v2_init_sequence(struct st7703 *ctx)
> > >                            0x28, 0x03, 0xff, 0x00, 0x00, 0x00, 0x00);
> > >     mipi_dsi_dcs_write_seq(dsi, ST7703_CMD_SETCYC, 0x80);
> > >     mipi_dsi_dcs_write_seq(dsi, ST7703_CMD_SETBGP, 0x0a, 0x0a);
> > > -   mipi_dsi_dcs_write_seq(dsi, ST7703_CMD_SETVCOM, 0x92, 0x92);
> > > -   mipi_dsi_dcs_write_seq(dsi, ST7703_CMD_SETPOWER_EXT, 0x25, 0x22,
> > > +   mipi_dsi_dcs_write_seq(dsi, ST7703_CMD_SETVCOM, 0x7f, 0x7f);
> > > +   mipi_dsi_dcs_write_seq(dsi, ST7703_CMD_SETPOWER_EXT, 0x26, 0x62,
> > >                            0xf0, 0x63);
> > >     mipi_dsi_dcs_write_seq(dsi, ST7703_CMD_SETMIPI, 0x33, 0x81, 0x05,
> > >                            0xf9, 0x0e, 0x0e, 0x20, 0x00, 0x00, 0x00, 0x00,
> > > --
> > > 2.43.0
> > >