On 20/06/2022 22:04, Serge Semin wrote: > On Mon, Jun 20, 2022 at 09:46:25PM +0200, Krzysztof Kozlowski wrote: >> On 20/06/2022 21:30, Serge Semin wrote: >>> On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote: >>>> From: Brad Larson <blarson@xxxxxxx> >>>> >>>> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller >>>> >>>> Signed-off-by: Brad Larson <blarson@xxxxxxx> >>>> --- >>>> Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++ >>>> 1 file changed, 2 insertions(+) >>>> >>>> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml >>>> index e25d44c218f2..2a55b947cffc 100644 >>>> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml >>>> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml >>>> @@ -73,6 +73,8 @@ properties: >>>> - renesas,r9a06g032-spi # RZ/N1D >>>> - renesas,r9a06g033-spi # RZ/N1S >>>> - const: renesas,rzn1-spi # RZ/N1 >>> >>>> + - description: AMD Pensando Elba SoC SPI Controller >>>> + const: amd,pensando-elba-spi >>> >>> Not enough. The driver requires to have a phandle reference to the >>> Pensando System Controller. So the property like >>> "amd,pensando-elba-syscon" is also needed to be added to the DT schema >>> otherwise should the dt-schema tool correctly handle the >>> "unevaluatedProperties: false" setting (Rob says it isn't fully >>> supported at the moment), the dtbs_check procedure will fail on your >>> dts evaluation. >> > >> The property was here before, now removed, so I assume it was also >> removed from the driver and DTS. Isn't that the case? > > Ah, the property has been indeed removed. The driver now searches for > the system controller by the next compatible string: > "amd,pensando-elba-syscon" using the > syscon_regmap_lookup_by_compatible() method. My mistake. Sorry for the > noise. > > * Though personally I'd prefer to have a property with the phandle > reference in order to signify the connection between the system controller > and the SPI-controller. Otherwise the implicit DT bindings like having > the "amd,pensando-elba-syscon"-compatible syscon gets to be > hidden behind the DT scene. But seeing we have already got the Microsemi > platform with such semantic, I can't insist on fixing this. I agree entirely, this should be explicit syscon-type property. Looking up for compatibles: - creates hidden (not expressed via bindings) dependency between nodes, - is not portable and several people struggled with it later and needed backward-compatible code (many examples, let's just give recent one: [1]) [1] https://lore.kernel.org/all/20220619151225.209029-10-tmaimon77@xxxxxxxxx/ Best regards, Krzysztof
