1 files changed, 145 insertions, 19 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 96aa75ddf87f..a645cd3ab163 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -1580,9 +1580,9 @@ static void ata_eh_analyze_serror(struct ata_link *link)
 	 * host links.  For disabled PMP links, only N bit is
 	 * considered as X bit is left at 1 for link plugging.
 	 */
-	hotplug_mask = 0;
-
-	if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
+	if (link->lpm_policy != ATA_LPM_MAX_POWER)
+		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
+	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
 		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
 	else
 		hotplug_mask = SERR_PHYRDY_CHG;
@@ -2784,8 +2784,9 @@ int ata_eh_reset(struct ata_link *link, int classify,
 	ata_eh_done(link, NULL, ATA_EH_RESET);
 	if (slave)
 		ata_eh_done(slave, NULL, ATA_EH_RESET);
-	ehc->last_reset = jiffies;	/* update to completion time */
+	ehc->last_reset = jiffies;		/* update to completion time */
 	ehc->i.action |= ATA_EH_REVALIDATE;
+	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
 
 	rc = 0;
  out:
@@ -3211,6 +3212,121 @@ static int ata_eh_maybe_retry_flush(struct ata_device *dev)
 	return rc;
 }
 
+/**
+ *	ata_eh_set_lpm - configure SATA interface power management
+ *	@link: link to configure power management
+ *	@policy: the link power management policy
+ *	@r_failed_dev: out parameter for failed device
+ *
+ *	Enable SATA Interface power management.  This will enable
+ *	Device Interface Power Management (DIPM) for min_power
+ * 	policy, and then call driver specific callbacks for
+ *	enabling Host Initiated Power management.
+ *
+ *	LOCKING:
+ *	EH context.
+ *
+ *	RETURNS:
+ *	0 on success, -errno on failure.
+ */
+static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
+			  struct ata_device **r_failed_dev)
+{
+	struct ata_port *ap = link->ap;
+	struct ata_eh_context *ehc = &link->eh_context;
+	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
+	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
+	unsigned int err_mask;
+	int rc;
+
+	/* if the link or host doesn't do LPM, noop */
+	if ((link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
+		return 0;
+
+	/*
+	 * DIPM is enabled only for MIN_POWER as some devices
+	 * misbehave when the host NACKs transition to SLUMBER.  Order
+	 * device and link configurations such that the host always
+	 * allows DIPM requests.
+	 */
+	ata_for_each_dev(dev, link, ENABLED) {
+		bool hipm = ata_id_has_hipm(dev->id);
+		bool dipm = ata_id_has_dipm(dev->id);
+
+		/* find the first enabled and LPM enabled devices */
+		if (!link_dev)
+			link_dev = dev;
+
+		if (!lpm_dev && (hipm || dipm))
+			lpm_dev = dev;
+
+		hints &= ~ATA_LPM_EMPTY;
+		if (!hipm)
+			hints &= ~ATA_LPM_HIPM;
+
+		/* disable DIPM before changing link config */
+		if (policy != ATA_LPM_MIN_POWER && dipm) {
+			err_mask = ata_dev_set_feature(dev,
+					SETFEATURES_SATA_DISABLE, SATA_DIPM);
+			if (err_mask && err_mask != AC_ERR_DEV) {
+				ata_dev_printk(dev, KERN_WARNING,
+					"failed to disable DIPM, Emask 0x%x\n",
+					err_mask);
+				rc = -EIO;
+				goto fail;
+			}
+		}
+	}
+
+	rc = ap->ops->set_lpm(link, policy, hints);
+	if (!rc && ap->slave_link)
+		rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
+
+	/*
+	 * Attribute link config failure to the first (LPM) enabled
+	 * device on the link.
+	 */
+	if (rc) {
+		if (rc == -EOPNOTSUPP) {
+			link->flags |= ATA_LFLAG_NO_LPM;
+			return 0;
+		}
+		dev = lpm_dev ? lpm_dev : link_dev;
+		goto fail;
+	}
+
+	/* 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)) {
+			err_mask = ata_dev_set_feature(dev,
+					SETFEATURES_SATA_ENABLE, SATA_DIPM);
+			if (err_mask && err_mask != AC_ERR_DEV) {
+				ata_dev_printk(dev, KERN_WARNING,
+					"failed to enable DIPM, Emask 0x%x\n",
+					err_mask);
+				rc = -EIO;
+				goto fail;
+			}
+		}
+	}
+
+	link->lpm_policy = policy;
+	if (ap && ap->slave_link)
+		ap->slave_link->lpm_policy = policy;
+	return 0;
+
+fail:
+	/* 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,
+				"disabling LPM on the link\n");
+		link->flags |= ATA_LFLAG_NO_LPM;
+	}
+	if (r_failed_dev)
+		*r_failed_dev = dev;
+	return rc;
+}
+
 static int ata_link_nr_enabled(struct ata_link *link)
 {
 	struct ata_device *dev;
@@ -3295,6 +3411,10 @@ static int ata_eh_schedule_probe(struct ata_device *dev)
 	ehc->saved_xfer_mode[dev->devno] = 0;
 	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
 
+	/* the link maybe in a deep sleep, wake it up */
+	if (link->lpm_policy > ATA_LPM_MAX_POWER)
+		link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER, ATA_LPM_EMPTY);
+
 	/* Record and count probe trials on the ering.  The specific
 	 * error mask used is irrelevant.  Because a successful device
 	 * detection clears the ering, this count accumulates only if
@@ -3396,8 +3516,7 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
 {
 	struct ata_link *link;
 	struct ata_device *dev;
-	int nr_failed_devs;
-	int rc;
+	int rc, nr_fails;
 	unsigned long flags, deadline;
 
 	DPRINTK("ENTER\n");
@@ -3438,7 +3557,6 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
 
  retry:
 	rc = 0;
-	nr_failed_devs = 0;
 
 	/* if UNLOADING, finish immediately */
 	if (ap->pflags & ATA_PFLAG_UNLOADING)
@@ -3523,13 +3641,17 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
 	}
 
 	/* the rest */
-	ata_for_each_link(link, ap, EDGE) {
+	nr_fails = 0;
+	ata_for_each_link(link, ap, PMP_FIRST) {
 		struct ata_eh_context *ehc = &link->eh_context;
 
+		if (sata_pmp_attached(ap) && ata_is_host_link(link))
+			goto config_lpm;
+
 		/* revalidate existing devices and attach new ones */
 		rc = ata_eh_revalidate_and_attach(link, &dev);
 		if (rc)
-			goto dev_fail;
+			goto rest_fail;
 
 		/* if PMP got attached, return, pmp EH will take care of it */
 		if (link->device->class == ATA_DEV_PMP) {
@@ -3541,7 +3663,7 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
 		if (ehc->i.flags & ATA_EHI_SETMODE) {
 			rc = ata_set_mode(link, &dev);
 			if (rc)
-				goto dev_fail;
+				goto rest_fail;
 			ehc->i.flags &= ~ATA_EHI_SETMODE;
 		}
 
@@ -3554,7 +3676,7 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
 					continue;
 				rc = atapi_eh_clear_ua(dev);
 				if (rc)
-					goto dev_fail;
+					goto rest_fail;
 			}
 		}
 
@@ -3564,21 +3686,25 @@ int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
 				continue;
 			rc = ata_eh_maybe_retry_flush(dev);
 			if (rc)
-				goto dev_fail;
+				goto rest_fail;
 		}
 
+	config_lpm:
 		/* configure link power saving */
-		if (ehc->i.action & ATA_EH_LPM)
-			ata_for_each_dev(dev, link, ALL)
-				ata_dev_enable_pm(dev, ap->lpm_policy);
+		if (link->lpm_policy != ap->target_lpm_policy) {
+			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
+			if (rc)
+				goto rest_fail;
+		}
 
 		/* this link is okay now */
 		ehc->i.flags = 0;
 		continue;
 
-dev_fail:
-		nr_failed_devs++;
-		ata_eh_handle_dev_fail(dev, rc);
+	rest_fail:
+		nr_fails++;
+		if (dev)
+			ata_eh_handle_dev_fail(dev, rc);
 
 		if (ap->pflags & ATA_PFLAG_FROZEN) {
 			/* PMP reset requires working host port.
@@ -3590,7 +3716,7 @@ dev_fail:
 		}
 	}
 
-	if (nr_failed_devs)
+	if (nr_fails)
 		goto retry;
 
  out: