[SCSI] isci: export phy events via ->lldd_control_phy()

Allow the sas-transport-class to update events for local phys via a new
PHY_FUNC_GET_EVENTS command to ->lldd_control_phy().  Fixup drivers that
are not prepared for new enum phy_func values, and unify
->lldd_control_phy() error codes.

These are the SAS defined phy events that are reported in a
smp-report-phy-error-log command:
 * /sys/class/sas_phy/<phyX>/invalid_dword_count
 * /sys/class/sas_phy/<phyX>/running_disparity_error_count
 * /sys/class/sas_phy/<phyX>/loss_of_dword_sync_count
 * /sys/class/sas_phy/<phyX>/phy_reset_problem_count

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/isci/phy.c b/drivers/scsi/isci/phy.c
index 430fc8f..ab48bb1 100644
--- a/drivers/scsi/isci/phy.c
+++ b/drivers/scsi/isci/phy.c
@@ -1313,6 +1313,17 @@
 		ret = isci_port_perform_hard_reset(ihost, iport, iphy);
 
 		break;
+	case PHY_FUNC_GET_EVENTS: {
+		struct scu_link_layer_registers __iomem *r;
+		struct sas_phy *phy = sas_phy->phy;
+
+		r = iphy->link_layer_registers;
+		phy->running_disparity_error_count = readl(&r->running_disparity_error_count);
+		phy->loss_of_dword_sync_count = readl(&r->loss_of_sync_error_count);
+		phy->phy_reset_problem_count = readl(&r->phy_reset_problem_count);
+		phy->invalid_dword_count = readl(&r->invalid_dword_counter);
+		break;
+	}
 
 	default:
 		dev_dbg(&ihost->pdev->dev,