3 files changed, 298 insertions, 7 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 51dbc522193..fa65b990f8b 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5009,6 +5009,122 @@ int ata_flush_cache(struct ata_device *dev)
 	return 0;
 }
 
+static int ata_host_set_request_pm(struct ata_host_set *host_set,
+				   pm_message_t mesg, unsigned int action,
+				   unsigned int ehi_flags, int wait)
+{
+	unsigned long flags;
+	int i, rc;
+
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+
+		/* Previous resume operation might still be in
+		 * progress.  Wait for PM_PENDING to clear.
+		 */
+		if (ap->pflags & ATA_PFLAG_PM_PENDING) {
+			ata_port_wait_eh(ap);
+			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
+		}
+
+		/* request PM ops to EH */
+		spin_lock_irqsave(ap->lock, flags);
+
+		ap->pm_mesg = mesg;
+		if (wait) {
+			rc = 0;
+			ap->pm_result = &rc;
+		}
+
+		ap->pflags |= ATA_PFLAG_PM_PENDING;
+		ap->eh_info.action |= action;
+		ap->eh_info.flags |= ehi_flags;
+
+		ata_port_schedule_eh(ap);
+
+		spin_unlock_irqrestore(ap->lock, flags);
+
+		/* wait and check result */
+		if (wait) {
+			ata_port_wait_eh(ap);
+			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
+			if (rc)
+				return rc;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ *	ata_host_set_suspend - suspend host_set
+ *	@host_set: host_set to suspend
+ *	@mesg: PM message
+ *
+ *	Suspend @host_set.  Actual operation is performed by EH.  This
+ *	function requests EH to perform PM operations and waits for EH
+ *	to finish.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ *
+ *	RETURNS:
+ *	0 on success, -errno on failure.
+ */
+int ata_host_set_suspend(struct ata_host_set *host_set, pm_message_t mesg)
+{
+	int i, j, rc;
+
+	rc = ata_host_set_request_pm(host_set, mesg, 0, ATA_EHI_QUIET, 1);
+	if (rc)
+		goto fail;
+
+	/* EH is quiescent now.  Fail if we have any ready device.
+	 * This happens if hotplug occurs between completion of device
+	 * suspension and here.
+	 */
+	for (i = 0; i < host_set->n_ports; i++) {
+		struct ata_port *ap = host_set->ports[i];
+
+		for (j = 0; j < ATA_MAX_DEVICES; j++) {
+			struct ata_device *dev = &ap->device[j];
+
+			if (ata_dev_ready(dev)) {
+				ata_port_printk(ap, KERN_WARNING,
+						"suspend failed, device %d "
+						"still active\n", dev->devno);
+				rc = -EBUSY;
+				goto fail;
+			}
+		}
+	}
+
+	host_set->dev->power.power_state = mesg;
+	return 0;
+
+ fail:
+	ata_host_set_resume(host_set);
+	return rc;
+}
+
+/**
+ *	ata_host_set_resume - resume host_set
+ *	@host_set: host_set to resume
+ *
+ *	Resume @host_set.  Actual operation is performed by EH.  This
+ *	function requests EH to perform PM operations and returns.
+ *	Note that all resume operations are performed parallely.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+void ata_host_set_resume(struct ata_host_set *host_set)
+{
+	ata_host_set_request_pm(host_set, PMSG_ON, ATA_EH_SOFTRESET,
+				ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
+	host_set->dev->power.power_state = PMSG_ON;
+}
+
 /**
  *	ata_port_start - Set port up for dma.
  *	@ap: Port to initialize
@@ -5651,20 +5767,55 @@ int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
 	return (tmp == bits->val) ? 1 : 0;
 }
 
-int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t state)
+void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t state)
 {
 	pci_save_state(pdev);
-	pci_disable_device(pdev);
-	pci_set_power_state(pdev, PCI_D3hot);
-	return 0;
+
+	if (state.event == PM_EVENT_SUSPEND) {
+		pci_disable_device(pdev);
+		pci_set_power_state(pdev, PCI_D3hot);
+	}
 }
 
-int ata_pci_device_resume(struct pci_dev *pdev)
+void ata_pci_device_do_resume(struct pci_dev *pdev)
 {
 	pci_set_power_state(pdev, PCI_D0);
 	pci_restore_state(pdev);
 	pci_enable_device(pdev);
 	pci_set_master(pdev);
+}
+
+int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+	struct ata_host_set *host_set = dev_get_drvdata(&pdev->dev);
+	int rc = 0;
+
+	rc = ata_host_set_suspend(host_set, state);
+	if (rc)
+		return rc;
+
+	if (host_set->next) {
+		rc = ata_host_set_suspend(host_set->next, state);
+		if (rc) {
+			ata_host_set_resume(host_set);
+			return rc;
+		}
+	}
+
+	ata_pci_device_do_suspend(pdev, state);
+
+	return 0;
+}
+
+int ata_pci_device_resume(struct pci_dev *pdev)
+{
+	struct ata_host_set *host_set = dev_get_drvdata(&pdev->dev);
+
+	ata_pci_device_do_resume(pdev);
+	ata_host_set_resume(host_set);
+	if (host_set->next)
+		ata_host_set_resume(host_set->next);
+
 	return 0;
 }
 #endif /* CONFIG_PCI */
@@ -5844,6 +5995,8 @@ EXPORT_SYMBOL_GPL(sata_scr_write);
 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
 EXPORT_SYMBOL_GPL(ata_port_online);
 EXPORT_SYMBOL_GPL(ata_port_offline);
+EXPORT_SYMBOL_GPL(ata_host_set_suspend);
+EXPORT_SYMBOL_GPL(ata_host_set_resume);
 EXPORT_SYMBOL_GPL(ata_id_string);
 EXPORT_SYMBOL_GPL(ata_id_c_string);
 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
@@ -5858,6 +6011,8 @@ EXPORT_SYMBOL_GPL(ata_pci_host_stop);
 EXPORT_SYMBOL_GPL(ata_pci_init_native_mode);
 EXPORT_SYMBOL_GPL(ata_pci_init_one);
 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
+EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
+EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
 EXPORT_SYMBOL_GPL(ata_pci_default_filter);
diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index b9df49a3621..4b6aa30f4d6 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -47,6 +47,8 @@
 
 static void __ata_port_freeze(struct ata_port *ap);
 static void ata_eh_finish(struct ata_port *ap);
+static void ata_eh_handle_port_suspend(struct ata_port *ap);
+static void ata_eh_handle_port_resume(struct ata_port *ap);
 
 static void ata_ering_record(struct ata_ering *ering, int is_io,
 			     unsigned int err_mask)
@@ -262,6 +264,9 @@ void ata_scsi_error(struct Scsi_Host *host)
  repeat:
 	/* invoke error handler */
 	if (ap->ops->error_handler) {
+		/* process port resume request */
+		ata_eh_handle_port_resume(ap);
+
 		/* fetch & clear EH info */
 		spin_lock_irqsave(ap->lock, flags);
 
@@ -274,12 +279,15 @@ void ata_scsi_error(struct Scsi_Host *host)
 
 		spin_unlock_irqrestore(ap->lock, flags);
 
-		/* invoke EH.  if unloading, just finish failed qcs */
-		if (!(ap->pflags & ATA_PFLAG_UNLOADING))
+		/* invoke EH, skip if unloading or suspended */
+		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 			ap->ops->error_handler(ap);
 		else
 			ata_eh_finish(ap);
 
+		/* process port suspend request */
+		ata_eh_handle_port_suspend(ap);
+
 		/* Exception might have happend after ->error_handler
 		 * recovered the port but before this point.  Repeat
 		 * EH in such case.
@@ -2101,3 +2109,119 @@ void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
 	ata_eh_recover(ap, prereset, softreset, hardreset, postreset);
 	ata_eh_finish(ap);
 }
+
+/**
+ *	ata_eh_handle_port_suspend - perform port suspend operation
+ *	@ap: port to suspend
+ *
+ *	Suspend @ap.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+static void ata_eh_handle_port_suspend(struct ata_port *ap)
+{
+	unsigned long flags;
+	int rc = 0;
+
+	/* are we suspending? */
+	spin_lock_irqsave(ap->lock, flags);
+	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
+	    ap->pm_mesg.event == PM_EVENT_ON) {
+		spin_unlock_irqrestore(ap->lock, flags);
+		return;
+	}
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
+
+	/* suspend */
+	ata_eh_freeze_port(ap);
+
+	if (ap->ops->port_suspend)
+		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
+
+	/* report result */
+	spin_lock_irqsave(ap->lock, flags);
+
+	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
+	if (rc == 0)
+		ap->pflags |= ATA_PFLAG_SUSPENDED;
+	else
+		ata_port_schedule_eh(ap);
+
+	if (ap->pm_result) {
+		*ap->pm_result = rc;
+		ap->pm_result = NULL;
+	}
+
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	return;
+}
+
+/**
+ *	ata_eh_handle_port_resume - perform port resume operation
+ *	@ap: port to resume
+ *
+ *	Resume @ap.
+ *
+ *	This function also waits upto one second until all devices
+ *	hanging off this port requests resume EH action.  This is to
+ *	prevent invoking EH and thus reset multiple times on resume.
+ *
+ *	On DPM resume, where some of devices might not be resumed
+ *	together, this may delay port resume upto one second, but such
+ *	DPM resumes are rare and 1 sec delay isn't too bad.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+static void ata_eh_handle_port_resume(struct ata_port *ap)
+{
+	unsigned long timeout;
+	unsigned long flags;
+	int i, rc = 0;
+
+	/* are we resuming? */
+	spin_lock_irqsave(ap->lock, flags);
+	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
+	    ap->pm_mesg.event != PM_EVENT_ON) {
+		spin_unlock_irqrestore(ap->lock, flags);
+		return;
+	}
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	/* spurious? */
+	if (!(ap->pflags & ATA_PFLAG_SUSPENDED))
+		goto done;
+
+	if (ap->ops->port_resume)
+		rc = ap->ops->port_resume(ap);
+
+	/* give devices time to request EH */
+	timeout = jiffies + HZ; /* 1s max */
+	while (1) {
+		for (i = 0; i < ATA_MAX_DEVICES; i++) {
+			struct ata_device *dev = &ap->device[i];
+			unsigned int action = ata_eh_dev_action(dev);
+
+			if ((dev->flags & ATA_DFLAG_SUSPENDED) &&
+			    !(action & ATA_EH_RESUME))
+				break;
+		}
+
+		if (i == ATA_MAX_DEVICES || time_after(jiffies, timeout))
+			break;
+		msleep(10);
+	}
+
+ done:
+	spin_lock_irqsave(ap->lock, flags);
+	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
+	if (ap->pm_result) {
+		*ap->pm_result = rc;
+		ap->pm_result = NULL;
+	}
+	spin_unlock_irqrestore(ap->lock, flags);
+}
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 5ac26260819..6cc497a2b6d 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -182,6 +182,7 @@ enum {
 
 	ATA_PFLAG_FLUSH_PORT_TASK = (1 << 16), /* flush port task */
 	ATA_PFLAG_SUSPENDED	= (1 << 17), /* port is suspended (power) */
+	ATA_PFLAG_PM_PENDING	= (1 << 18), /* PM operation pending */
 
 	/* struct ata_queued_cmd flags */
 	ATA_QCFLAG_ACTIVE	= (1 << 0), /* cmd not yet ack'd to scsi lyer */
@@ -549,6 +550,9 @@ struct ata_port {
 	struct list_head	eh_done_q;
 	wait_queue_head_t	eh_wait_q;
 
+	pm_message_t		pm_mesg;
+	int			*pm_result;
+
 	void			*private_data;
 
 	u8			sector_buf[ATA_SECT_SIZE]; /* owned by EH */
@@ -603,6 +607,9 @@ struct ata_port_operations {
 	void (*scr_write) (struct ata_port *ap, unsigned int sc_reg,
 			   u32 val);
 
+	int (*port_suspend) (struct ata_port *ap, pm_message_t mesg);
+	int (*port_resume) (struct ata_port *ap);
+
 	int (*port_start) (struct ata_port *ap);
 	void (*port_stop) (struct ata_port *ap);
 
@@ -667,6 +674,8 @@ extern void ata_std_ports(struct ata_ioports *ioaddr);
 extern int ata_pci_init_one (struct pci_dev *pdev, struct ata_port_info **port_info,
 			     unsigned int n_ports);
 extern void ata_pci_remove_one (struct pci_dev *pdev);
+extern void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t state);
+extern void ata_pci_device_do_resume(struct pci_dev *pdev);
 extern int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t state);
 extern int ata_pci_device_resume(struct pci_dev *pdev);
 extern int ata_pci_clear_simplex(struct pci_dev *pdev);
@@ -687,6 +696,9 @@ extern int ata_port_online(struct ata_port *ap);
 extern int ata_port_offline(struct ata_port *ap);
 extern int ata_scsi_device_resume(struct scsi_device *);
 extern int ata_scsi_device_suspend(struct scsi_device *, pm_message_t state);
+extern int ata_host_set_suspend(struct ata_host_set *host_set,
+				pm_message_t mesg);
+extern void ata_host_set_resume(struct ata_host_set *host_set);
 extern int ata_ratelimit(void);
 extern unsigned int ata_busy_sleep(struct ata_port *ap,
 				   unsigned long timeout_pat,