| Message ID | 20230330101752.429804-2-francesco@dolcini.it |
|---|---|
| State | New |
| Headers | show |
| Series | [v1,1/2] dt-bindings: display: bridge: sn65dsi83: Add DSI video mode | expand |
On 4/3/23 23:15, Francesco Dolcini wrote: > On Mon, Apr 03, 2023 at 04:06:22PM -0500, Rob Herring wrote: >> On Thu, Mar 30, 2023 at 12:17:51PM +0200, Francesco Dolcini wrote: >>> From: Francesco Dolcini <francesco.dolcini@toradex.com> >>> >>> SN65DSI8[34] device supports burst video mode and non-burst video mode >>> with sync events or with sync pulses packet transmission as described in >>> the DSI specification. >>> >>> Add property to select the expected mode, this allows for example to >>> select a mode that is compatible with the DSI host interface. >> >> Why does this need to be in DT? > >> The source and sink drivers should know what their capabilities are >> and pick the best common one. > > Is there a best mode? I think yes: Burst (is better than) Sync Events (is better than) Sync Pulses Burst is most energy efficient, Sync-Pulses is the simplest and least energy efficient and with most constraints. > Isn't this a decision how do we want the 2 peers > to communicate? I don't think so, I believe the Host and nearest bridge should be able to negotiate their capabilities (mode, link rate, etc.) within the DRM subsystem. > For the MIPI-DSI Linux/DRM experts: am I missing something? Is there > another way to have a DSI video sink to ask for a specific mode? I'm afraid this is not implemented yet, so ... plumbing needed. [...]
diff --git a/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi83.yaml b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi83.yaml index 48a97bb3e2e0..ebee16726b02 100644 --- a/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi83.yaml +++ b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi83.yaml @@ -35,6 +35,14 @@ properties: vcc-supply: description: A 1.8V power supply (see regulator/regulator.yaml). + dsi-video-mode: + description: | + 0 - burst-mode + 1 - non-burst with sync event + 2 - non-burst with sync pulse + $ref: /schemas/types.yaml#/definitions/uint32 + enum: [0, 1, 2] + ports: $ref: /schemas/graph.yaml#/properties/ports