Hello Mark,

On Fri, 24 Mar 2023 18:51:19 +0000
Mark Brown [off-list ref] wrote:

On Fri, Mar 24, 2023 at 10:36:39AM +0100, Maxime Chevallier wrote:

quoted

With regmap->reg_base and regmap->reg_downshift, the actual register
address that is going to be used for the next operation might not
be the same as the one we have as an input. Addresses can be offset
with reg_base and shifted, which will affect alignment.

Check for alignment on the real register address.  

It is not at all clear to me that the combination of stride and
downshift particularly makes sense, and especially not that the
stride should be applied after downshifting rather than to what
the user is passing in.

I agree on the part where the ordering of "adding and offset, then
down/upshifting" isn't natural. This is the order in which operations
are done today, and from what I could gather, only the ocelot-spi MFD
driver uses both of these operations.

It would indeed make sense to first shift the register to have the
proper spacing between register addresses, then adding the offset.

So maybe we should address that in ocelot-spi in the next iteration,
Colin, would you agree ?

Thanks,

Maxime