On 27/08/2024 23:34, Laurent Pinchart wrote: > On Tue, Aug 27, 2024 at 10:12:33AM +0200, Niklas Söderlund wrote: >> On 2024-08-27 08:31:22 +0200, Krzysztof Kozlowski wrote: >>> On Mon, Aug 26, 2024 at 04:43:47PM +0200, Niklas Söderlund wrote: >>>> The ISP Channel Selector IP is the same for all current Gen4 devices. >>>> This was not known when adding support for V3U and V4H and a single SoC >>>> specific compatible was used. >>>> >>>> Before adding more SoC specific bindings for V4M add a family compatible >>>> fallback for Gen4. That way the driver only needs to be updated once for >>>> Gen4, and we still have the option to fix any problems in the driver if >>>> any testable differences between the SoCs are found. >>>> >>>> There are already DTS files using the V3U and V4H compatibles which >>>> needs to be updated to not produce a warning for DTS checks. The driver >>>> also needs to kept the compatible values to be backward compatible , but >>>> for new Gen4 SoCs such as V4M we can avoid this. >>>> >>>> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx> >>>> --- >>>> * Changes since v1 >>>> - New in v2. >>>> --- >>>> Documentation/devicetree/bindings/media/renesas,isp.yaml | 3 ++- >>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/Documentation/devicetree/bindings/media/renesas,isp.yaml b/Documentation/devicetree/bindings/media/renesas,isp.yaml >>>> index 33650a1ea034..730c86f2d7b1 100644 >>>> --- a/Documentation/devicetree/bindings/media/renesas,isp.yaml >>>> +++ b/Documentation/devicetree/bindings/media/renesas,isp.yaml >>>> @@ -22,6 +22,7 @@ properties: >>>> - enum: >>>> - renesas,r8a779a0-isp # V3U >>>> - renesas,r8a779g0-isp # V4H >>>> + - const: renesas,rcar-gen4-isp # Generic R-Car Gen4 >>> >>> Adding generic fallback post-factum is odd, does not feel reliable. >>> Instead use specific compatibles as fallbacks. >> >> I agree, it feels a bit odd. But this was the road we hammered out at >> great pain for how to be able to move forward with this issue for the >> other IP block involved in video capture for R-Car Gen4, VIN [1]. This >> just mirrors that long discussion decision for the R-Car CSISP. >> >> I would hate to have different solutions for the two. >> >> 1. [PATCH v5 0/6] rcar-vin: Add support for R-Car V4M >> https://lore.kernel.org/all/20240704161620.1425409-1-niklas.soderlund+renesas@xxxxxxxxxxxx/ > > The compatible fallback for VIN has been added following a request from > Conor and Rob, so it would be nice if the three of you could agree to > achieve consistency in the bindings :-) Don't twist our answers. You need fallback, but specific, not family. There was a countless number of answers from Rob that specific compatibles are preferred. Look, Conor's reply: https://lore.kernel.org/all/20240620-gating-coherent-af984389b2d7@spud/ Do you see family fallback? I think "r8a779g0" is SoC. Look here: https://lore.kernel.org/all/20240610-screen-wolverine-78370c66d40f@spud/ Or here https://lore.kernel.org/all/20240624-rented-danger-300652ab8eeb@wendy/ where Conor agrees against! So let me actually NAK it - you got multiple comments on VIN to use specific compatible. Best regards, Krzysztof
