sata_mv wait for empty+idle
authorMark Lord <liml@rtr.ca>
Fri, 2 May 2008 06:09:14 +0000 (02:09 -0400)
committerJeff Garzik <jgarzik@redhat.com>
Tue, 6 May 2008 15:37:39 +0000 (11:37 -0400)
commit9b2c4e0bae854fb5e88c9cacc0dacf21631c5cb0
tree52f4be46f543e22c35d43806ad38764c165e9b3d
parent616d4a98ad8749ebe17a8fcac67df65c321350ac
sata_mv wait for empty+idle

When performing EH, it is recommended to wait for the EDMA engine
to empty out requests-in-progress before disabling EDMA.

Introduce code to poll the EDMA_STATUS register for idle/empty bits
before disabling EDMA.  For non-EH operation, this will normally exit
without delay, other than the register read.

A later series of patches may focus on eliminating this and various
other register reads (when possible) throughout the driver,
but for now we're focussing on solid reliablity.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
drivers/ata/sata_mv.c