On Mon, Apr 03, 2023 at 04:01:17PM -0500, Rob Herring wrote: > On Fri, Mar 31, 2023 at 11:40:01AM +0200, Francesco Dolcini wrote: > > On Fri, Mar 31, 2023 at 10:48:15AM +0200, Krzysztof Kozlowski wrote: > > > On 30/03/2023 11:59, Francesco Dolcini wrote: > > > > From: Francesco Dolcini <francesco.dolc...@toradex.com> > > > > > > > > Add new toshiba,input-rgb-mode property to describe the actual signal > > > > connection on the parallel RGB input interface. > > > > > > > > Signed-off-by: Francesco Dolcini <francesco.dolc...@toradex.com> > > > > --- > > > > .../bindings/display/bridge/toshiba,tc358768.yaml | 15 +++++++++++++++ > > > > 1 file changed, 15 insertions(+) > > > > > > > > diff --git > > > > a/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml > > > > > > > > b/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml > > > > index 8f22093b61ae..2638121a2223 100644 > > > > --- > > > > a/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml > > > > +++ > > > > b/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml > > > > @@ -42,6 +42,21 @@ properties: > > > > clock-names: > > > > const: refclk > > > > > > > > + toshiba,input-rgb-mode: > > > > + description: | > > > > + Parallel Input (RGB) Mode. > > > > + > > > > + RGB inputs (PD[23:0]) color arrangement as documented in the > > > > datasheet > > > > + and in the table below. > > > > + > > > > + 0 = R[7:0], G[7:0], B[7:0] > > > > > > RGB888? > > > > Or anything else - like a RGB666 - just connecting to GND the unused > > pins. > > If the bridge is configured for RGB666, then that's fine. If not, the > unused pins should be driven with either the MSB of each component. > Otherwise, you'd can't fully saturate the colors.
> > > > + 1 = R[1:0], G[1:0], B[1:0], R[7:2], G[7:2], B[7:2] > > > > + 2 = 8’b0, R[4:0], G[5:0], B[4:0] > > > > > > Isn't this RGB565? > > > > > > Don't we have already properties like this? e.g. colorspace? > > > > It's not really the colorspace this property. > > > > tc358768 is a parallel RGB to DSI bridge, it has 24 bit parallel input > > line. > > > > The way this lines are connected is configurable with this parameter, if you > > look at mode 0 and 1 they all allow to have a RGB888 or a RGB666 or a > > RGB565 mapping. This just configure some internal mux, it's not strictly > > about the RGB mode. > > This is the same as other cases. There's a need for describing the > interface. It keeps coming up and I keep saying to go create something > common. I am not aware of other discussion on the topic, do you have any pointer I can look at? What I'd like to re-iterate here once more is that this configuration is about how the external 24-bit parallel RGB lines are mapped withing this bridge. It's not mapping the linux media bus format (e.g. not MEDIA_BUS_FMT_RBG888_1X24 or alike). This bridge allow for a limited set of combination (3) as described in this binding. Francesco