Re: [PATCH 1/2] arm64: dts: qcom: Enable lvds panel-DV215FHM-R01 for rb3gen2 industrial mezzanine

[Dmitry Baryshkov]

On Wed, Nov 12, 2025 at 10:53:36AM -0600, Bjorn Andersson wrote:
> On Wed, Nov 12, 2025 at 05:02:20PM +0200, Dmitry Baryshkov wrote:
> > On Wed, Nov 12, 2025 at 08:18:11PM +0530, Gopi Botlagunta wrote:
> > > Below is the routing diagram of dsi lanes from qcs6490 soc to
> > > mezzanine.
> > > 
> > > DSI0 --> SW1403.4 --> LT9611uxc --> hdmi port
> > >                  |
> > >                   --> SW2700.1 --> dsi connector
> > >                               |
> > >                                --> LT9211c --> LVDS connector
> > > 
> > > Disable hdmi connector for industrial mezzanine and enable
> > > LT9211c bridge and lvds panel node.
> > > LT9211c is powered by default with reset gpio connected to 117.
> > > 
> > > Signed-off-by: Yi Zhang <zhanyi@xxxxxxxxxxxxxxxx>
> > > Signed-off-by: Gopi Botlagunta <venkata.botlagunta@xxxxxxxxxxxxxxxx>
> > > ---
> > >  .../qcom/qcs6490-rb3gen2-industrial-mezzanine.dtso | 106 +++++++++++++++++++++
> > >  1 file changed, 106 insertions(+)
> > > 
> > > diff --git a/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2-industrial-mezzanine.dtso b/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2-industrial-mezzanine.dtso
> > > index 619a42b5ef48..cc8ee1643167 100644
> > > --- a/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2-industrial-mezzanine.dtso
> > > +++ b/arch/arm64/boot/dts/qcom/qcs6490-rb3gen2-industrial-mezzanine.dtso
> > > @@ -8,6 +8,112 @@
> > >  #include <dt-bindings/clock/qcom,gcc-sc7280.h>
> > >  #include <dt-bindings/pinctrl/qcom,pmic-gpio.h>
> > >  
> > > +/ {
> > > +
> > > +	hdmi-connector {
> > > +		status = "disabled";
> > > +	};
> > > +
> > > +	panel_lvds: panel-lvds@0 {
> > > +		compatible = "panel-lvds";
> > 
> > Please describe the actual panel using compatible, etc. It's not that
> > this is some generic uknown LVDS panel.
> > 
> 
> I presume the mezzanine doesn't have a panel, so how do we provide the
> description of the mezzanine such that a developer can quickly get up to
> speed with their specific panel connected to it?
> 
> Do we leave this node disabled, just for reference, or do we specify a
> specific panel and then have the developer copy and adopt this to their
> panel?
> 
> The benefit of doing it like that is that we provide a complete example
> and something we can test. But at the same time, If I presume we might
> have users of the mezzanine without an attached LVDS panel?
> 
> > > +		data-mapping = "vesa-24";
> > > +		width-mm = <476>;
> > > +		height-mm = <268>;
> 
> The way this patch is written we certainly have some specific panel in
> mind...

It's even mentioned in the subject: BOE DV215FHM-R01. Having a proper
panel compatible is demanded by the panel-lvds bindings.


-- 
With best wishes
Dmitry