On Mon, 2023-01-30 at 15:39 -0600, Rob Herring wrote: > On Mon, Jan 30, 2023 at 04:39:05PM +0800, Liu Ying wrote: > > On Sun, 2023-01-29 at 12:46 +0100, Krzysztof Kozlowski wrote: > > > On 28/01/2023 04:47, Liu Ying wrote: > > > > NXP i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register > > > > which > > > > configures parallel display format by using the > > > > "PARALLEL_DISP_FORMAT" > > > > field. Add device tree bindings for the display format > > > > configuration. > > > > > > > > Signed-off-by: Liu Ying <victor....@nxp.com> > > > > --- > > > > .../display/bridge/nxp,imx93-pdfc.yaml | 78 > > > > +++++++++++++++++++ > > > > 1 file changed, 78 insertions(+) > > > > create mode 100644 > > > > Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > > pdfc.yaml > > > > > > > > diff --git > > > > a/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > > pdfc.yaml > > > > b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > > pdfc.yaml > > > > new file mode 100644 > > > > index 000000000000..a84bfb46b01d > > > > --- /dev/null > > > > +++ > > > > b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > > pdfc.yaml > > > > @@ -0,0 +1,78 @@ > > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > > +%YAML 1.2 > > > > +--- > > > > +$id: > > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fdisplay%2Fbridge%2Fnxp%2Cimx93-pdfc.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C3e8db7ce3170451bc0e208db030a6ad0%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638107115502467822%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=c%2BQ%2Bhpov6L9b905ozKPrkWiTzaRD3ZFsEh0urw5evsQ%3D&reserved=0 > > > > +$schema: > > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fmeta-schemas%2Fcore.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C3e8db7ce3170451bc0e208db030a6ad0%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638107115502467822%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=SkPZLJIR9uoqk4mRqSsfu963S%2Baa7xXmyCqzR36LJ30%3D&reserved=0 > > > > + > > > > +title: NXP i.MX93 Parallel Display Format Configuration > > > > + > > > > +maintainers: > > > > + - Liu Ying <victor....@nxp.com> > > > > + > > > > +description: | > > > > + The i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX > > > > register > > > > which > > > > + configures parallel display format by using the > > > > "PARALLEL_DISP_FORMAT" > > > > + field. > > > > + > > > > +properties: > > > > + compatible: > > > > + const: nxp,imx93-pdfc > > > > > > > > > Based on description, I have doubts this is a separate bridge > > > device. > > > Why this is not part of display driver/bindings? > > > > The relevant display controller in i.MX93 SoC is LCDIF. From > > hardware > > design PoV, the parallel display format configuration logic is not > > a > > part of LCDIF. Instead, it's a part of i.MX93 mediamix blk-ctrl. > > The > > blk-ctrl includes controls for miscellaneous devices with small > > logics, > > like this parallel display format configuration, LVDS Display > > Bridge(LDB, see fsl,ldb.yaml) and so on. The below pipeline > > describes > > data flow of a parallel display LCD panel: > > > > DRAM -> LCDIF -> parallel display format configuration -> LCD panel > > > > So, the parallel display format configuration appears to be a > > separate > > bridge. > > > > > > > > We do not create usually devices for single registers, because > > > they > > > are > > > not a devices. Devices are a bit more complex - have some pin > > > inputs/outputs, not a register only. Of course there are > > > exception, > > > but > > > this one does not look like one. > > > > IMHO, this one is a standalone device although it is controlled by > > one > > single register. It's input pins connect to LCDIF and output pins > > connect to i.MX93 SoC's pins/pads. > > Fair enough. It needs to be defined as part of the mediamix blkctrl > schema though.
Do you mean that we can keep this schema and need to allow child devices in fsl,imx93-media-blk-ctrl.yaml? Cc'ing Peng. Peng, it appears that you are listed in the maintainers of fsl,imx93- media-blk-ctrl.yaml. I think it needs to be extended to allow child devices. Do you consider to do that? Regards, Liu Ying > > Rob