Hi Niklas,
On Mon, Jun 24, 2024 at 4:43 PM Niklas Söderlund
<niklas.soderlund+renesas@xxxxxxxxxxxx> wrote:
> The two Gen4 SoCs released (V4H and V4M) that have a video capture
> pipeline the VIN IP are very similar.
>
> The datasheet for the two SoCs have small nuances around the Pre-Clip
> registers ELPrC and EPPrC in three use-cases, interlaced images,
> embedded data and RAW8 input. On V4H the values written to the registers
> are based on odd numbers while on V4M they are even numbers, values are
> based on the input image size. No board that uses these SoCs which also
> have the external peripherals to test these nuances exists. Most likely
> this is an issue in the datasheet.
>
> Before adding 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 two SoCs is found.
>
> There are already DTS files using the renesas,vin-r8a779g0 compatible
> which needs to be updated to not produce a warning for DTS checks. And
> the driver will need to kept compatible with renesas,vin-r8a779g0, but
> for new Gen4 SoCs such as V4M we can avoid this.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> ---
> * Changes since v3
> - New in v4.
Thanks for your patch!
> --- a/Documentation/devicetree/bindings/media/renesas,vin.yaml
> +++ b/Documentation/devicetree/bindings/media/renesas,vin.yaml
> @@ -53,7 +53,10 @@ properties:
> - renesas,vin-r8a77990 # R-Car E3
> - renesas,vin-r8a77995 # R-Car D3
> - renesas,vin-r8a779a0 # R-Car V3U
I think R-Car V3U should be moved below, too, as it's the first
member of the R-Car Gen4 family, despite the name.
> + - items:
> + - enum:
> - renesas,vin-r8a779g0 # R-Car V4H
> + - const: renesas,rcar-gen4-vin # Generic R-Car Gen4
If all differences in the pipeline can be devised from the topology
in DT:
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>
> reg:
> maxItems: 1
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
