Re: [PATCH v2 1/9] dmaengine: Support bus widths of 32 bytes and above

On Wed, Aug 12, 2026 at 10:08:34AM +0100, Nuno Sá wrote:
> On Tue, Aug 11, 2026 at 11:28:04PM +0530, Vinod Koul wrote:

...

> Just remembered that bitmap.h is already included in dmaengine.h anyways. bitops.h
> is because of __set/clear_bit().

Oh my gosh, true! bitmap.h implies all bit ops, so no need then a new header.
Indeed the whole hell is due to dma_cap_zero(). So, while your patch won't
change the current state, in lieu of the said previously I would like to have
a split, but since dma_cap_zero() is used almost everywhere, perhaps make
__dma_cap_zero() an exported function then? This, of course, can be done later
but if we start from the more mess, it will be harder to untangle, so I still
think the separate header is a way to go. And perhaps these capabilities also
can be split to dmaengine-capmask.h (with a fallback inclusion in dmaengine.h)
so in the future we can only include it when it's needed.

Looking into the structure of the include/linux/dma* I even would think of
something like include/linux/dma/engine/*.h with include/linux/dmaengine.h
to collect (for backward compatibility), where the first citizen may be
your API, followed by split capmask.h.

-- 
With Best Regards,
Andy Shevchenko