Re: [PATCH] ARM: dts: r8a7742-iwg21d-q7-dbcm-ca: Add OV7725 nodes

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Prabhakar,

On Fri, Nov 20, 2020 at 4:13 PM Lad Prabhakar
<prabhakar.mahadev-lad.rj@bp.renesas.com> wrote:
> Add the ov7725 endpoint nodes to the camera daughter board. The ov7725
> sensors can be populated on I2C{0,1,2,3} buses.
>
> By default the VIN{0,1,2,3} are tied to OV5640{0,1,2,3} endpoints
> respectively in the camera DB dts hence the remote-endpoint property in
> OV7725{0,1,2,3} endpoints is commented out.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>

Thanks for your patch!

The camera definitions look mostly OK to me.

IIUIC, these are 4 plug-in cameras, that can be used instead of the
(currently described) 4 other OV5640-based plug-in cameras?
In addition, the user can mix and match them, in the 4 available
slots (J11-J14), which would require editing the DTS?

Wouldn't it be easier to have separate DTS files for the OV7725 and
OV5640 cameras, and #include them from r8a7742-iwg21d-q7-dbcm-ca.dts?

    /* 8bit CMOS Camera 1 (J13) */
    #define MCLK_CAM    &mclk_cam1
    #define ...
    /* Comment the below according to connected cameras */
    #include "ov5640.dts"
    //#include "ov7725.dts"
    #undef MCLK_CAM
    #undef ...

    [...]

> --- a/arch/arm/boot/dts/r8a7742-iwg21d-q7-dbcm-ca.dts
> +++ b/arch/arm/boot/dts/r8a7742-iwg21d-q7-dbcm-ca.dts

> @@ -152,6 +198,30 @@
>                         };
>                 };
>         };
> +
> +       ov7725@21 {
> +               status = "disabled";

This one is disabled, the three others aren't?

> +               compatible = "ovti,ov7725";
> +               reg = <0x21>;
> +               clocks = <&mclk_cam3>;
> +
> +               port {
> +                       ov7725_2: endpoint {
> +                               bus-width = <8>;
> +                               bus-type = <6>;
> +                               /*
> +                                * uncomment remote-endpoint property to
> +                                * tie ov7725_2 to vin2ep also make
> +                                * sure to comment/remove remote-endpoint
> +                                * property from ov5640_2 endpoint and
> +                                * replace remote-endpoint property in
> +                                * vin2ep node with
> +                                * remote-endpoint = <&ov7725_2>;
> +                                */
> +                               /* remote-endpoint = <&vin2ep>; */
> +                       };
> +               };
> +       };
>  };

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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