[Linux-stm32] [PATCH v2 1/1] spi: use dmaengine_desc_set_callback()

[Wolfram Sang]

> > No, (partial) Rb != Ack.
> 
> It is, because there is no partial Rb tag.

Heh, just what I wrote a minute ago in the workflows-thread. The clean
solution is to introduce one. I'd vote for it.