Re: [PATCH] dma-mapping: Stub out dma_{alloc,free,map}_pages() API

[James Clark]

On 16/06/2025 2:19 pm, Christoph Hellwig wrote:
> On Mon, Jun 16, 2025 at 02:15:56PM +0100, James Clark wrote:
> > > Yes it does, it has a few modes that don't require it. Presumably we can't
> > > just add a depends into the kconfig for all devices because they might not
> > > be using DMA.
> >
> > *for all the different variants of spi-fsl-dpsi devices I mean
>
> This is drivers/spi/spi-fsl-dspi.c?
>
> Yes, looks like it is one of those rare devices supporting a DMA and
> non-DMA mode.  But everything seems nicely guarded off using
> "dspi->devtype_data->trans_mode == DSPI_DMA_MODE" checks there.  So
> wrap them into a little helper using IS_ENABLED(CONFIG_HAS_DMA) and
> everything should be sorted out.

Sure, I don't mind doing it.

But separately to that, I still think making the stubs consistent would 
save people a lot of time diagnosing build failures if they switch 
existing code to any of those 3 functions. Principle of Least 
Astonishment and all that.