Re: [PATCH 2/4] drm/panel: simple: Add support for the Lemaker BL035 3.5" LCD

From: Maxime Ripard
Date: Wed Oct 24 2018 - 12:58:14 EST


On Tue, Oct 23, 2018 at 12:08:17PM +0200, Paul Kocialkowski wrote:
> Hi,
>
> Le mercredi 10 octobre 2018 à 16:58 +0200, Maxime Ripard a écrit :
> > On Wed, Oct 10, 2018 at 01:41:32PM +0200, Paul Kocialkowski wrote:
> > > This adds support for the 3.5" LCD panel from Lemaker, sold for use with
> > > BananaPi boards. It comes with a 24-bit RGB888 parallel interface and
> > > requires an active-low DE signal
> > >
> > > Signed-off-by: Paul Kocialkowski <contact@xxxxxxxx>
> > > ---
> > > drivers/gpu/drm/panel/panel-simple.c | 27 +++++++++++++++++++++++++++
> > > 1 file changed, 27 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
> > > index 97964f7f2ace..229080fcf65e 100644
> > > --- a/drivers/gpu/drm/panel/panel-simple.c
> > > +++ b/drivers/gpu/drm/panel/panel-simple.c
> > > @@ -1461,6 +1461,30 @@ static const struct panel_desc kyo_tcg121xglp = {
> > > .bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
> > > };
> > >
> > > +static const struct drm_display_mode lemaker_bl035_mode = {
> > > + .clock = 7000,
> > > + .hdisplay = 320,
> > > + .hsync_start = 320 + 20,
> > > + .hsync_end = 320 + 20 + 30,
> > > + .htotal = 320 + 20 + 30 + 38,
> > > + .vdisplay = 240,
> > > + .vsync_start = 240 + 4,
> > > + .vsync_end = 240 + 4 + 3,
> > > + .vtotal = 240 + 4 + 3 + 15,
> > > + .vrefresh = 60,
> > > +};
> > > +
> > > +static const struct panel_desc lemaker_bl035 = {
> > > + .modes = &lemaker_bl035_mode,
> > > + .num_modes = 1,
> > > + .size = {
> > > + .width = 70,
> > > + .height = 52,
> > > + },
> > > + .bus_format = MEDIA_BUS_FMT_RGB888_1X24,
> > > + .bus_flags = DRM_BUS_FLAG_DE_LOW,
> > > +};
> > > +
> > > static const struct drm_display_mode lg_lb070wv8_mode = {
> > > .clock = 33246,
> > > .hdisplay = 800,
> > > @@ -2456,6 +2480,9 @@ static const struct of_device_id platform_of_match[] = {
> > > }, {
> > > .compatible = "kyo,tcg121xglp",
> > > .data = &kyo_tcg121xglp,
> > > + }, {
> > > + .compatible = "lemaker,bl035",
> > > + .data = &lemaker_bl035,
> >
> > You should document that new compatible. Also, where is this name
> > coming from? Is it the name it's sold under? something you came up
> > with?
>
> Oh right, I forgot to document the compatible (and add the new vendor).
>
> The name "BL035" comes from the PCB itself, where it reads "BL035-RGB-
> 002" under the Lemaker logo. I went for "BL035" to keep it short.
>
> The latter part seems to be the PCB revision. According to the fex
> files[0], the timings are the same for all the screens of the same size
> (regardless of revision), so that revision probably shouldn't be in the
> panel name.
>
> As for the "RGB" part, Lemaker only makes 3.5 and 5 inch LCDs with a
> parallel RGB interface and 7 and 10.1 inch LCDs with LVDS, so there is
> no ambiguity for now.
>
> Do you think it makes sense to keep that part in the panel name
> nevertheless?

I'd just put the full reference, to be on the safe side.

Thanks!
Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com