rapidio/tsi721_dma: update error reporting from prep_sg callback
authorAlexandre Bounine <alexandre.bounine@idt.com>
Tue, 22 Mar 2016 21:26:59 +0000 (14:26 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Tue, 22 Mar 2016 22:36:02 +0000 (15:36 -0700)
commit83472457505c454592d91807754135d0ad34b125
tree3c93685eba4fff5416df6201fdd6f9b4c2fc7774
parent72d8a0d23083ba89fb00a7ad9b07419e34ebe47c
rapidio/tsi721_dma: update error reporting from prep_sg callback

Switch to returning error-valued pointer instead of simple NULL pointer.
This allows to properly identify situation when request queue is full
and therefore gives to upper layer an option to retry operation later.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/rapidio/devices/tsi721_dma.c