diff options
| author | Tejun Heo <tj@kernel.org> | 2010-12-09 18:13:15 +0300 |
|---|---|---|
| committer | Jeff Garzik <jgarzik@redhat.com> | 2010-12-24 21:34:34 +0300 |
| commit | e5005b15c91f3362036067bde5210d5c78af2f0d (patch) | |
| tree | cbddea07bc4b27921f40a7cc0c0a687d7239041e /drivers/ata | |
| parent | f08dc1ac6b15c681f4643d8da1700e06c3855608 (diff) | |
| download | linux-e5005b15c91f3362036067bde5210d5c78af2f0d.tar.xz | |
libata: issue DIPM enable commands with LPM state updated
Low level drivers may behave differently depending on the current
link->lpm_policy. During ata_eh_set_lpm(), DIPM enable commands are
issued after the successful completion of ap->ops->set_lpm(), which
means that the controller is already in the target state. This causes
DIPM enable commands to be processed with mismatching controller power
state and link->lpm_policy value.
In ahci, link->lpm_policy is used to ignore certain PHY events if LPM
is enabled; however, as DIPM commands are issued with stale
link->lpm_policy, they sometimes end up triggering these conditions
and get aborted leading to LPM configuration failure.
Fix it by updating link->lpm_policy before issuing DIPM enable
commands.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Diffstat (limited to 'drivers/ata')
| -rw-r--r-- | drivers/ata/libata-eh.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index 5e590504f3aa..17a637877d03 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -3275,6 +3275,7 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL; struct ata_eh_context *ehc = &link->eh_context; struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL; + enum ata_lpm_policy old_policy = link->lpm_policy; unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM; unsigned int err_mask; int rc; @@ -3338,6 +3339,14 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, goto fail; } + /* + * Low level driver acked the transition. Issue DIPM command + * with the new policy set. + */ + link->lpm_policy = policy; + if (ap && ap->slave_link) + ap->slave_link->lpm_policy = policy; + /* host config updated, enable DIPM if transitioning to MIN_POWER */ ata_for_each_dev(dev, link, ENABLED) { if (policy == ATA_LPM_MIN_POWER && ata_id_has_dipm(dev->id)) { @@ -3353,12 +3362,14 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, } } - link->lpm_policy = policy; - if (ap && ap->slave_link) - ap->slave_link->lpm_policy = policy; return 0; fail: + /* restore the old policy */ + link->lpm_policy = old_policy; + if (ap && ap->slave_link) + ap->slave_link->lpm_policy = old_policy; + /* if no device or only one more chance is left, disable LPM */ if (!dev || ehc->tries[dev->devno] <= 2) { ata_link_printk(link, KERN_WARNING, |