On Fri, 23 Jul 2021 18:14:22 +0100
Mark Brown [off-list ref] wrote:

On Fri, Jul 23, 2021 at 06:10:22PM +0100, Jonathan Cameron wrote:

quoted

@Mark.  This has come up a few times recently.  Are we now safe to assume
that regmap will always copy data when used with SPI and hence we no
longer need to ensure DMA safe buffers?     

Only for single register I/O, I'd not assume that for things like raw
I/O.

Thanks for the confirmation.  So in this driver that means we
need DMA safe buffers for the regmap_bulk_ calls.  Easiest approach
is probably to use a __cacheline_aligned buffer at the end of the
iio_priv() structure.

Note that my name is spelt Mark.

I'll blame Friday.

Thanks,

Jonathan