1 files changed, 30 insertions, 4 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 01831312c360..94919ad03df1 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -2783,6 +2783,12 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
                 } else if (dev->class == ATA_DEV_UNKNOWN &&
                            ehc->tries[dev->devno] &&
                            ata_class_enabled(ehc->classes[dev->devno])) {
+                        /* Temporarily set dev->class, it will be
+                         * permanently set once all configurations are
+                         * complete.  This is necessary because new
+                         * device configuration is done in two
+                         * separate loops.
+                         */
                         dev->class = ehc->classes[dev->devno];
 
                         if (dev->class == ATA_DEV_PMP)
@@ -2790,6 +2796,11 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
                         else
                                 rc = ata_dev_read_id(dev, &dev->class,
                                                      readid_flags, dev->id);
+
+                        /* read_id might have changed class, store and reset */
+                        ehc->classes[dev->devno] = dev->class;
+                        dev->class = ATA_DEV_UNKNOWN;
+
                         switch (rc) {
                         case 0:
                                 /* clear error info accumulated during probe */
@@ -2799,13 +2810,11 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
                         case -ENOENT:
                                 /* IDENTIFY was issued to non-existent
                                  * device.  No need to reset.  Just
-                                 * thaw and kill the device.
+                                 * thaw and ignore the device.
                                  */
                                 ata_eh_thaw_port(ap);
-                                dev->class = ATA_DEV_UNKNOWN;
                                 break;
                         default:
-                                dev->class = ATA_DEV_UNKNOWN;
                                 goto err;
                         }
                 }
@@ -2826,11 +2835,15 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
                     dev->class == ATA_DEV_PMP)
                         continue;
 
+                dev->class = ehc->classes[dev->devno];
+
                 ehc->i.flags |= ATA_EHI_PRINTINFO;
                 rc = ata_dev_configure(dev);
                 ehc->i.flags &= ~ATA_EHI_PRINTINFO;
-                if (rc)
+                if (rc) {
+                        dev->class = ATA_DEV_UNKNOWN;
                         goto err;
+                }
 
                 spin_lock_irqsave(ap->lock, flags);
                 ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
@@ -3494,6 +3507,8 @@ static void ata_eh_handle_port_suspend(struct ata_port *ap)
  */
 static void ata_eh_handle_port_resume(struct ata_port *ap)
 {
+        struct ata_link *link;
+        struct ata_device *dev;
         unsigned long flags;
         int rc = 0;
 
@@ -3508,6 +3523,17 @@ static void ata_eh_handle_port_resume(struct ata_port *ap)
 
         WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
 
+        /*
+         * Error timestamps are in jiffies which doesn't run while
+         * suspended and PHY events during resume isn't too uncommon.
+         * When the two are combined, it can lead to unnecessary speed
+         * downs if the machine is suspended and resumed repeatedly.
+         * Clear error history.
+         */
+        ata_for_each_link(link, ap, HOST_FIRST)
+                ata_for_each_dev(dev, link, ALL)
+                        ata_ering_clear(&dev->ering);
+
         ata_acpi_set_state(ap, PMSG_ON);
 
         if (ap->ops->port_resume)