[S390] pm: ccwgroup bus power management callbacks

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

2 files changed, 83 insertions, 5 deletions

diff --git a/arch/s390/include/asm/ccwgroup.h b/arch/s390/include/asm/ccwgroup.h
index a27f68985a79..c79c1e787b86 100644
--- a/arch/s390/include/asm/ccwgroup.h
+++ b/arch/s390/include/asm/ccwgroup.h
@@ -38,6 +38,11 @@ struct ccwgroup_device {
  * @set_online: function called when device is set online
  * @set_offline: function called when device is set offline
  * @shutdown: function called when device is shut down
+ * @prepare: prepare for pm state transition
+ * @complete: undo work done in @prepare
+ * @freeze: callback for freezing during hibernation snapshotting
+ * @thaw: undo work done in @freeze
+ * @restore: callback for restoring after hibernation
  * @driver: embedded driver structure
  */
 struct ccwgroup_driver {
@@ -51,6 +56,11 @@ struct ccwgroup_driver {
         int (*set_online) (struct ccwgroup_device *);
         int (*set_offline) (struct ccwgroup_device *);
         void (*shutdown)(struct ccwgroup_device *);
+        int (*prepare) (struct ccwgroup_device *);
+        void (*complete) (struct ccwgroup_device *);
+        int (*freeze)(struct ccwgroup_device *);
+        int (*thaw) (struct ccwgroup_device *);
+        int (*restore)(struct ccwgroup_device *);
 
         struct device_driver driver;
 };
diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index 22ce765d537e..a5a62f1f7747 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -1,11 +1,10 @@
 /*
- *  drivers/s390/cio/ccwgroup.c
  *  bus driver for ccwgroup
  *
- *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
- *                       IBM Corporation
- *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
- *               Cornelia Huck (cornelia.huck@de.ibm.com)
+ *  Copyright IBM Corp. 2002, 2009
+ *
+ *  Author(s): Arnd Bergmann (arndb@de.ibm.com)
+ *             Cornelia Huck (cornelia.huck@de.ibm.com)
  */
 #include <linux/module.h>
 #include <linux/errno.h>
@@ -501,6 +500,74 @@ static void ccwgroup_shutdown(struct device *dev)
                 gdrv->shutdown(gdev);
 }
 
+static int ccwgroup_pm_prepare(struct device *dev)
+{
+        struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+        struct ccwgroup_driver *gdrv = to_ccwgroupdrv(gdev->dev.driver);
+
+        /* Fail while device is being set online/offline. */
+        if (atomic_read(&gdev->onoff))
+                return -EAGAIN;
+
+        if (!gdev->dev.driver || gdev->state != CCWGROUP_ONLINE)
+                return 0;
+
+        return gdrv->prepare ? gdrv->prepare(gdev) : 0;
+}
+
+static void ccwgroup_pm_complete(struct device *dev)
+{
+        struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+        struct ccwgroup_driver *gdrv = to_ccwgroupdrv(dev->driver);
+
+        if (!gdev->dev.driver || gdev->state != CCWGROUP_ONLINE)
+                return;
+
+        if (gdrv->complete)
+                gdrv->complete(gdev);
+}
+
+static int ccwgroup_pm_freeze(struct device *dev)
+{
+        struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+        struct ccwgroup_driver *gdrv = to_ccwgroupdrv(gdev->dev.driver);
+
+        if (!gdev->dev.driver || gdev->state != CCWGROUP_ONLINE)
+                return 0;
+
+        return gdrv->freeze ? gdrv->freeze(gdev) : 0;
+}
+
+static int ccwgroup_pm_thaw(struct device *dev)
+{
+        struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+        struct ccwgroup_driver *gdrv = to_ccwgroupdrv(gdev->dev.driver);
+
+        if (!gdev->dev.driver || gdev->state != CCWGROUP_ONLINE)
+                return 0;
+
+        return gdrv->thaw ? gdrv->thaw(gdev) : 0;
+}
+
+static int ccwgroup_pm_restore(struct device *dev)
+{
+        struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+        struct ccwgroup_driver *gdrv = to_ccwgroupdrv(gdev->dev.driver);
+
+        if (!gdev->dev.driver || gdev->state != CCWGROUP_ONLINE)
+                return 0;
+
+        return gdrv->restore ? gdrv->restore(gdev) : 0;
+}
+
+static struct dev_pm_ops ccwgroup_pm_ops = {
+        .prepare = ccwgroup_pm_prepare,
+        .complete = ccwgroup_pm_complete,
+        .freeze = ccwgroup_pm_freeze,
+        .thaw = ccwgroup_pm_thaw,
+        .restore = ccwgroup_pm_restore,
+};
+
 static struct bus_type ccwgroup_bus_type = {
         .name   = "ccwgroup",
         .match  = ccwgroup_bus_match,
@@ -508,6 +575,7 @@ static struct bus_type ccwgroup_bus_type = {
         .probe  = ccwgroup_probe,
         .remove = ccwgroup_remove,
         .shutdown = ccwgroup_shutdown,
+        .pm = &ccwgroup_pm_ops,
 };