On Tue, Apr 2, 2024 at 9:06 PM Conor Dooley <conor@xxxxxxxxxx> wrote: > > On Tue, Apr 02, 2024 at 01:59:25PM +0300, Alexandru Ardelean wrote: > > On some HW designs, it's easier for the layout if the P/N pins are swapped. > > The driver currently has a DT property to do that. > > "currently", because 1/2 adds it. bindings patches should precede the > driver patches in the series, so please swap the patches and remove this > portion of the description. ack; i'll invert the order and remove this; > > > > > This change documents the 'lontium,pn-swap' property. > > > > Signed-off-by: Alexandru Ardelean <alex@xxxxxxxxxxx> > > --- > > .../devicetree/bindings/display/bridge/lontium,lt8912b.yaml | 6 ++++++ > > 1 file changed, 6 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml > > index 2cef252157985..3a804926b288a 100644 > > --- a/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml > > +++ b/Documentation/devicetree/bindings/display/bridge/lontium,lt8912b.yaml > > @@ -24,6 +24,12 @@ properties: > > maxItems: 1 > > description: GPIO connected to active high RESET pin. > > > > + lontium,pn-swap: > > + description: Swap the polarities of the P/N pins in software. > > + On some HW designs, the layout is simplified if the P/N pins > > + are inverted. > > Please explain what configuration of a board would cause these to be > swapped, rather than why someone might want to configure the board this > way. I've got no idea what this hardware is actually doing, so this is > being pulled out of a hat, but I'd expect something like "Some boards > swap the polarity of the P/N pins, use this property to indicate this to > software". ack if it's fine with you, i'll use your suggested description; for a broader context, we were using a DSI-HDMI converter [1] from SomLabs on a different (than SomLabs) board; and we were not seeing anything on the HDMI-connected display; as I understand it, some DSI-HDMI bridges support P/N auto-inversion; this one doesn't AFAICT; on this DSI-HDMI converter [1], we've noticed that the P/N pins were inverted from the DSI to the chip (vs what we expected to see) after changing the register value (for the P/N swap), it worked; our conclusion was that, the design of the converter (board) was done as-such, because it made the layout easier [1] https://wiki.somlabs.com/index.php/SL-MIPI-LVDS-HDMI-CNV-11_Datasheet_and_Pinout > > > + type: boolean > > The type here should be flag. ack; i'll change the type > > Cheers, > Conor. > > > + > > ports: > > $ref: /schemas/graph.yaml#/properties/ports > > > > -- > > 2.44.0 > >
