The last_issued variable uses an atomic type, which is only
incremented inside a protected region, and then read. Everywhere else
only reads the value, so it isn't using atomic_t correctly, and it
doesn't even need to. Moreover, the DMA engine code provides us with
a variable for this already - chan.cookie. Use chan.cookie instead.
Also, avoid negative dma_cookie_t values - negative returns from
tx_submit() mean failure, yet in reality we always succeed. Restart
from cookie 1, just like other DMA engine drivers do.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
91aa5fadb8