libata: Don't disable dipm with SET FEATURES

LPM seems to get hung up while disabling DIPM, and after thinking
about this a bit, I don't think we really need to manually disable it
anyway.

Signed-off-by:  Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 10 insertions, 8 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 164c7d9514f9..3ed3cf2f5568 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -676,10 +676,11 @@ static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
                 if (rc)
                         return rc;
 
-                /* disable DIPM */
-                if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
-                        err_mask = ata_dev_set_feature(dev,
-                                        SETFEATURES_SATA_DISABLE, SATA_DIPM);
+                /*
+                 * we don't have to disable DIPM since IPM flags
+                 * disallow transitions to SLUMBER, which effectively
+                 * disable DIPM if it does not support PARTIAL
+                 */
                 break;
         case NOT_AVAILABLE:
         case MAX_PERFORMANCE:
@@ -689,10 +690,11 @@ static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
                 if (rc)
                         return rc;
 
-                /* disable DIPM */
-                if (ata_dev_enabled(dev) && (dev->flags & ATA_DFLAG_DIPM))
-                        err_mask = ata_dev_set_feature(dev,
-                                        SETFEATURES_SATA_DISABLE, SATA_DIPM);
+                /*
+                 * we don't have to disable DIPM since IPM flags
+                 * disallow all transitions which effectively
+                 * disable DIPM anyway.
+                 */
                 break;
         }