On Wed, Jun 07, 2023 at 09:59:47PM +0200, Noralf Trønnes wrote: > > > On 6/7/23 13:55, Leonard Göhrs wrote: > > Some MIPI DBI panels support a three wire mode (clock, chip select, > > bidirectional data) that can be used to ask the panel if it is already set > > up by e.g. the bootloader and can thus skip the initialization. > > This enables a flicker-free boot. > > > > Signed-off-by: Leonard Göhrs <l.goehrs@xxxxxxxxxxxxxx> > > --- > > .../devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml b/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml > > index c07da1a9e6288..2f0238b770eba 100644 > > --- a/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml > > +++ b/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml > > @@ -87,6 +87,8 @@ properties: > > Logic level supply for interface signals (Vddi). > > No need to set if this is the same as power-supply. > > > > + spi-3wire: true > > + > > I don't think this should be added here. spi-cpha and spi-cpol are also > supported but they are not mentioned. Instead those are documented in > bindings/spi/spi-controller.yaml. Why they're not documented in > bindings/spi/spi-peripheral-props.yaml instead which this binding has a > ref to, I have no idea. spi-peripheral-props.yaml are properties of the controller in the peripheral nodes. spi-cpha and spi-cpol are properties of the device which are completely invalid on some devices. We can only check that by documenting where they are valid. I think spi-3wire is similar. There should be more explanation in the spi-peripheral-props.yaml commit history. Rob
