Re: [PATCH v1 17/43] dt-bindings: spi: Add Cirrus EP93xx

[Nikita Shubin]

On Thu, 1 Jun 2023 13:55:03 +0100
Mark Brown <broonie@xxxxxxxxxx> wrote:

> On Thu, Jun 01, 2023 at 03:41:54PM +0300, Nikita Shubin wrote:
> > Mark Brown <broonie@xxxxxxxxxx> wrote:  
> > > On Thu, Jun 01, 2023 at 08:34:08AM +0300, Nikita Shubin wrote:  
> 
> > > > +  cirrus,ep9301-use-dma:
> > > > +    description: Flag indicating that the SPI should use dma
> > > > +    type: boolean    
> 
> > > My previous feedback on this property still applies.  
> 
> > > > +  cirrus,ep9301-use-dma:  
> 
> > The reason is that ep93xx DMA state is not quite device-tree ready
> > at this moment, and clients use it with the help of:  
> 
> > https://elixir.bootlin.com/linux/v6.4-rc4/source/include/linux/platform_data/dma-ep93xx.h
> >  
> 
> > I was hoping to slip by without changing much in ep93xx DMA driver,
> > so  
> 
> You're definign new ABI here, that's not a good thing to do for a
> temporary workaround.
> 
> > I can move "use-dma" to module parameters, if this is acceptable.  
> 
> That's less bad.  I guess you could also define the bindings for the
> DMA controller so that the properties are there then instead of
> properly using the DMA API in the clients just check to see if the
> DMA properties are present and then proceed accordingly?

This sounds like a way to go. Thank you, Mark!