[SCSI] ibmvscsi: Add suspend/resume support

Adds support for resuming from suspend for IBM VSCSI devices. We may have
lost an interrupt over the suspend, so we just kick the interrupt handler
to process anything that is outstanding. We expect to find a transport event
indicating we need to reestablish our CRQ.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index e3a18e0..dc1bcbe 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -71,6 +71,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/delay.h>
 #include <linux/of.h>
+#include <linux/pm.h>
 #include <asm/firmware.h>
 #include <asm/vio.h>
 #include <scsi/scsi.h>
@@ -1991,6 +1992,19 @@
 }
 
 /**
+ * ibmvscsi_resume: Resume from suspend
+ * @dev:	device struct
+ *
+ * We may have lost an interrupt across suspend/resume, so kick the
+ * interrupt handler
+ */
+static int ibmvscsi_resume(struct device *dev)
+{
+	struct ibmvscsi_host_data *hostdata = dev_get_drvdata(dev);
+	return ibmvscsi_ops->resume(hostdata);
+}
+
+/**
  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we 
  * support.
  */
@@ -2000,6 +2014,10 @@
 };
 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
 
+static struct dev_pm_ops ibmvscsi_pm_ops = {
+	.resume = ibmvscsi_resume
+};
+
 static struct vio_driver ibmvscsi_driver = {
 	.id_table = ibmvscsi_device_table,
 	.probe = ibmvscsi_probe,
@@ -2008,6 +2026,7 @@
 	.driver = {
 		.name = "ibmvscsi",
 		.owner = THIS_MODULE,
+		.pm = &ibmvscsi_pm_ops,
 	}
 };