Hi Laurent,
On Tue, Sep 26, 2017 at 2:39 PM, Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
> On Tuesday, 26 September 2017 14:47:35 EEST Geert Uytterhoeven wrote:
>> On Tue, Sep 26, 2017 at 12:05 PM, Laurent Pinchart wrote:
>> > The FCP instances associated with a VSPI must be treated differently
>> > than the ones associated with another type of VSP. Add a new compatible
>> > string to allow telling them apart.
>> >
>> > Signed-off-by: Laurent Pinchart
>> > <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
>> > ---
>> >
>> > Documentation/devicetree/bindings/media/renesas,fcp.txt | 3 ++-
>> > 1 file changed, 2 insertions(+), 1 deletion(-)
>> >
>> > diff --git a/Documentation/devicetree/bindings/media/renesas,fcp.txt
>> > b/Documentation/devicetree/bindings/media/renesas,fcp.txt index
>> > 3ec91803ba58..c1f28736e2d6 100644
>> > --- a/Documentation/devicetree/bindings/media/renesas,fcp.txt
>> > +++ b/Documentation/devicetree/bindings/media/renesas,fcp.txt
>> > @@ -11,7 +11,8 @@ are paired with. These DT bindings currently support the
>> > FCPV and FCPF.>
>> > - compatible: Must be one or more of the following
>> >
>> > - - "renesas,fcpv" for generic compatible 'FCP for VSP'
>> > + - "renesas,fcpvi" for generic compatible 'FCP for VSPI'
>> > + - "renesas,fcpv" for generic compatible 'FCP for VSP' (all other VSPs)
>> >
>> > - "renesas,fcpf" for generic compatible 'FCP for FDP'
>>
>> You may want to update the paragraph before that, referring to three types
>> of FCP.
>
> As far as I know the FCP-VSPI and FCP-VSP[^I] are the same type of device,
> with different SoC integration.
OK. So they should use the same compatible value?
>> Just wondering: as FCPVI vs. FCPV is programmable through the FCPVSEL
>> bit, can you deduce the type using the renesas,fcp link in the corresponding
>> VSP node in DT?
>
> You could possibly, if you had a link from the FCP to the VSP in DT. As
> there's none, the type can't be currently inferred from DT at probe time. We
> could pass the type from the VSP driver to the FCP driver, but I'm not sure I
> want to go that way. If the FCP-VSPI and VSP[^I] are identicaly and need
> different software configuration due to being used by different types of VSPs
> it would make sense, but if there are hardware differences between the FCPs
> then I think they should be described in DT.
Given the FCPVSEL bit, it looks like there's no difference, and software is
supposed to specify configuration.
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
