Re: [PATCH v3 1/9] dt-bindings: media: Add Renesas CEU bindings

From: Geert Uytterhoeven
Date: Fri Jan 05 2018 - 03:57:16 EST


On Thu, Jan 4, 2018 at 11:28 PM, Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
> On Thursday, 4 January 2018 18:03:09 EET Jacopo Mondi wrote:
>> Add bindings documentation for Renesas Capture Engine Unit (CEU).

>> +++ b/Documentation/devicetree/bindings/media/renesas,ceu.txt
>> @@ -0,0 +1,85 @@
>> +Renesas Capture Engine Unit (CEU)
>> +----------------------------------------------
>> +
>> +The Capture Engine Unit is the image capture interface found in the Renesas
>> +SH Mobile and RZ SoCs.
>> +
>> +The interface supports a single parallel input with data bus width of 8 or
>> 16
>> +bits.
>> +
>> +Required properties:
>> +- compatible: Must be one of the following.
>> + - "renesas,r7s72100-ceu" for CEU units found in R7S72100 (RZ/A1) SoCs.
>> + - "renesas,ceu" as a generic fallback.
>
> As asked in my review of patch 3/9, what's your policy for compatible strings
> ? As far as I understand there's no generic CEU, as the SH4 and RZ versions
> are not compatible. Should the "renesas,ceu" compatible string then be
> replaced by "renesas,rz-ceu" ?

If they're not compatible, it indeed doesn't make much sense to have a
generic "renesas,ceu".

Note that anything with "rz-" is a bad idea, as after RZ/A1, Renesas introduced
RZ/G1, RZ/N1, and RZ/T1, which are completely different (yes I know
we have a few of these in use, unfortunately).

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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-- Linus Torvalds