[PATCH] dt-bindings: mtd: jedec,spi-nor: Document CPOL/CPHA support
geert at linux-m68k.org
Tue Feb 14 07:22:15 PST 2023
On Tue, Feb 14, 2023 at 3:44 PM Miquel Raynal <miquel.raynal at bootlin.com> wrote:
> geert+renesas at glider.be wrote on Tue, 14 Feb 2023 15:26:43 +0100:
> > SPI EEPROMs typically support both SPI Mode 0 (CPOL=CPHA=0) and Mode 3
> > (CPOL=CPHA=1). However, using the latter is currently flagged as an
> > error by "make dtbs_check", e.g.:
> > arch/arm/boot/dts/r8a7791-koelsch.dtb: flash at 0: Unevaluated properties are not allowed ('spi-cpha', 'spi-cpol' were unexpected)
> > From schema: Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
> > Fix this by documenting support for CPOL=CPHA=1.
> > Fixes: 233363aba72ac638 ("spi/panel: dt-bindings: drop CPHA and CPOL from common properties")
> > Signed-off-by: Geert Uytterhoeven <geert+renesas at glider.be>
> > ---
> > Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml | 7 +++++++
> > 1 file changed, 7 insertions(+)
> > diff --git a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
> > index f86255ce13af0871..bb62ac4585822982 100644
> > --- a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
> > +++ b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
> > @@ -76,6 +76,13 @@ properties:
> > If "broken-flash-reset" is present then having this property does not
> > make any difference.
> > + spi-cpol: true
> > + spi-cpha: true
> I see that spi-cpol and spi-cpha are described in spi-controller.yaml
> which references spi-peripheral-props.yaml, but jedec,spi-nor.yaml
> only references spi-peripheral-props.yaml leading to spi-cpol and
> spi-cpha not being recognized as valid properties.
> Wouldn't it be cleaner to to have these two properties defined in
> spi-peripheral-props.yaml instead?
They were moved out of that file by the commit referenced in the
Fixes: tag above, because they are not supported by all SPI targets.
It's the responsibility of the SPI target bindings to list what is supported.
> > +
> > +dependencies:
> > + spi-cpol: [ spi-cpha ]
> > + spi-cpha: [ spi-cpol ]
> > +
> > unevaluatedProperties: false
> > examples:
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at 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
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