Re: [PATCH v2 3/4] ASoC: dt-bindings: fsl-sai: allow only one dma-names

[Frank Li <Frank.li@nxp.com>]

On Thu, Feb 29, 2024 at 06:57:29PM +0000, Conor Dooley wrote:
> On Thu, Feb 29, 2024 at 06:55:58PM +0000, Conor Dooley wrote:
> > On Tue, Feb 27, 2024 at 03:54:11PM -0500, Frank Li wrote:
> > > Some sai only connect one direction. So allow only "rx" or "tx" for
> > > dma-names.
> > 
> > Which sai? Can you restrict this per compatible please, so that someone
> > cannot add 2 dmas for ones where only the tx is supported.
> > 
> > |  dmas:
> > |    minItems: 1
> > |    items:
> > |      - description: DMA controller phandle and request line for RX
> > |      - description: DMA controller phandle and request line for TX
> > 
> > The binding already allows only one, but it documents that the first dma
> > is always the RX dma, and that doesn't change with this patch..
> 
> I said "doesn't change" - but I don't think you can change this
> trivially, as something could rely on the first dma being the rx one.
> You'd have to check that there is nothing using these using indices
> rather than names before making any changes here.

Linux driver and dts with tx only work well. Only issue is dtb_check will
report error. I want to eliminate these DTB_CHECK warning.

And it also reasonable, only rx or tx for a special SAI.

Can we remove 'description'? dmas should already descripted at common place
and 'RX' and 'TX' are listed at 'dma-names'

Frank

> 
> > 
> > Cheers,
> > Conor.
> > 
> > > 
> > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > ---
> > >  Documentation/devicetree/bindings/sound/fsl,sai.yaml | 12 ++++++++----
> > >  1 file changed, 8 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/sound/fsl,sai.yaml b/Documentation/devicetree/bindings/sound/fsl,sai.yaml
> > > index 2456d958adeef..0302752d58a2b 100644
> > > --- a/Documentation/devicetree/bindings/sound/fsl,sai.yaml
> > > +++ b/Documentation/devicetree/bindings/sound/fsl,sai.yaml
> > > @@ -86,10 +86,14 @@ properties:
> > >        - description: DMA controller phandle and request line for TX
> > >  
> > >    dma-names:
> > > -    minItems: 1
> > > -    items:
> > > -      - const: rx
> > > -      - const: tx
> > > +    oneOf:
> > > +      - items:
> > > +          - const: rx
> > > +          - const: tx
> > > +      - items:
> > > +          - enum:
> > > +              - rx
> > > +              - tx
> > >  
> > >    interrupts:
> > >      items:
> > > 
> > > -- 
> > > 2.34.1
> > > 
> 
>