tree bc31e1fbea4180a6822abe4247c9cfdb59e6b206
parent 3a93a159c61e38a12f7ecbb3a25cf3f012abcf7a
author Jan Nikitenko <jan.nikitenko@gmail.com> 1216873797 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1216921650 -0700

spi: au1550_spi: improve pio transfer mode

Improve PIO transfer mode of au1550 spi controller by continuing of spi
transfer, instead of aborting transfer when transmit underflow interrupt
occurrs.

Verified by oscilloscope that the spi clock pauses on trasmit underflow,
so transfer continuation is perfectly valid even though au1550 datasheet
says that on tx underflow zeroes will be transfered.

Also make some error messages more specific.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>