libata: retry link resume if necessary

Interestingly, when SIDPR is used in ata_piix, writes to DET in
SControl sometimes get ignored leading to detection failure.  Update
sata_link_resume() such that it reads back SControl after clearing DET
and retry if it's not clear.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: fengxiangjun <fengxiangjun@neusoft.com>
Reported-by: Jim Faulkner <jfaulkne@ccs.neu.edu>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Tejun Heo 2010-01-11 11:14:44 +09:00 committed by Jeff Garzik
parent 0b67c7439f
commit 5040ab67a2
2 changed files with 35 additions and 8 deletions

View file

@ -354,6 +354,9 @@ enum {
/* max tries if error condition is still set after ->error_handler */
ATA_EH_MAX_TRIES = 5,
/* sometimes resuming a link requires several retries */
ATA_LINK_RESUME_TRIES = 5,
/* how hard are we gonna try to probe/recover devices */
ATA_PROBE_MAX_TRIES = 3,
ATA_EH_DEV_TRIES = 3,