[SCSI] isci: ->lldd_ata_check_ready handler

Report to libata whether the link to the given domain_device is up and the
signature fis has been received.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/isci/init.c b/drivers/scsi/isci/init.c
index c20fda0..68d9bc2 100644
--- a/drivers/scsi/isci/init.c
+++ b/drivers/scsi/isci/init.c
@@ -193,6 +193,9 @@
 	.lldd_lu_reset		= isci_task_lu_reset,
 	.lldd_query_task	= isci_task_query_task,
 
+	/* ata recovery called from ata-eh */
+	.lldd_ata_check_ready	= isci_ata_check_ready,
+
 	/* Port and Adapter management */
 	.lldd_clear_nexus_port	= isci_task_clear_nexus_port,
 	.lldd_clear_nexus_ha	= isci_task_clear_nexus_ha,
diff --git a/drivers/scsi/isci/port.c b/drivers/scsi/isci/port.c
index e55ef65..c5ae94d 100644
--- a/drivers/scsi/isci/port.c
+++ b/drivers/scsi/isci/port.c
@@ -1675,6 +1675,31 @@
 	return ret;
 }
 
+int isci_ata_check_ready(struct domain_device *dev)
+{
+	struct isci_port *iport = dev->port->lldd_port;
+	struct isci_host *ihost = dev_to_ihost(dev);
+	struct isci_remote_device *idev;
+	unsigned long flags;
+	int rc = 0;
+
+	spin_lock_irqsave(&ihost->scic_lock, flags);
+	idev = isci_lookup_device(dev);
+	spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+	if (!idev)
+		goto out;
+
+	if (test_bit(IPORT_RESET_PENDING, &iport->state))
+		goto out;
+
+	rc = !!iport->active_phy_mask;
+ out:
+	isci_put_device(idev);
+
+	return rc;
+}
+
 void isci_port_deformed(struct asd_sas_phy *phy)
 {
 	struct isci_host *ihost = phy->ha->lldd_ha;
diff --git a/drivers/scsi/isci/port.h b/drivers/scsi/isci/port.h
index a0dcdae..321b987 100644
--- a/drivers/scsi/isci/port.h
+++ b/drivers/scsi/isci/port.h
@@ -303,4 +303,5 @@
 
 int isci_port_perform_hard_reset(struct isci_host *ihost, struct isci_port *iport,
 				 struct isci_phy *iphy);
+int isci_ata_check_ready(struct domain_device *dev);
 #endif /* !defined(_ISCI_PORT_H_) */