Move the DMA request muxing into the slave prepare code and txd
release/completion code. This means we only hold the DMA request
mux while there are descriptors waiting to be started or are in
progress.
This leaves txd->direction as a write-only variable; remove it.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Russell King
c48d496329