[S390] pm: vmlogrdr power management callbacks

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/char/vmlogrdr.c

@@ -3,7 +3,7 @@
  *	character device driver for reading z/VM system service records
  *
  *
- *	Copyright 2004 IBM Corporation
+ *	Copyright IBM Corp. 2004, 2009
  *	character device driver for reading z/VM system service records,
  *	Version 1.0
  *	Author(s): Xenia Tkatschow <xenia@us.ibm.com>
@@ -660,6 +660,29 @@ static struct attribute *vmlogrdr_attrs[] = {
 	NULL,
 };
 
+static int vmlogrdr_pm_prepare(struct device *dev)
+{
+	int rc;
+	struct vmlogrdr_priv_t *priv = dev->driver_data;
+
+	rc = 0;
+	if (priv) {
+		spin_lock_bh(&priv->priv_lock);
+		if (priv->dev_in_use)
+			rc = -EBUSY;
+		spin_unlock_bh(&priv->priv_lock);
+	}
+	if (rc)
+		pr_err("vmlogrdr: device %s is busy. Refuse to suspend.\n",
+		       dev_name(dev));
+	return rc;
+}
+
+
+static struct dev_pm_ops vmlogrdr_pm_ops = {
+	.prepare = vmlogrdr_pm_prepare,
+};
+
 static struct attribute_group vmlogrdr_attr_group = {
 	.attrs = vmlogrdr_attrs,
 };
@@ -668,6 +691,7 @@ static struct class *vmlogrdr_class;
 static struct device_driver vmlogrdr_driver = {
 	.name = "vmlogrdr",
 	.bus  = &iucv_bus,
+	.pm = &vmlogrdr_pm_ops,
 };
 
 
@@ -729,6 +753,7 @@ static int vmlogrdr_register_device(struct vmlogrdr_priv_t *priv)
 		dev->bus = &iucv_bus;
 		dev->parent = iucv_root;
 		dev->driver = &vmlogrdr_driver;
+		dev->driver_data = priv;
 		/*
 		 * The release function could be called after the
 		 * module has been unloaded. It's _only_ task is to