powerpc/vio: Add power management support

Adds support for suspend/resume for VIO devices. This is needed for
support for HMC initiated hibernation.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c
index 2a3428bef83a..b8e311d64ad5 100644
--- a/arch/powerpc/kernel/vio.c
+++ b/arch/powerpc/kernel/vio.c
@@ -1381,6 +1381,29 @@ static int vio_hotplug(struct device *dev, struct kobj_uevent_env *env)
         return 0;
 }
 
+static int vio_pm_suspend(struct device *dev)
+{
+        const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+
+        if (pm && pm->suspend)
+                return pm->suspend(dev);
+        return 0;
+}
+
+static int vio_pm_resume(struct device *dev)
+{
+        const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+
+        if (pm && pm->resume)
+                return pm->resume(dev);
+        return 0;
+}
+
+const struct dev_pm_ops vio_dev_pm_ops = {
+        .suspend = vio_pm_suspend,
+        .resume = vio_pm_resume,
+};
+
 static struct bus_type vio_bus_type = {
         .name = "vio",
         .dev_attrs = vio_dev_attrs,
@@ -1388,6 +1411,7 @@ static struct bus_type vio_bus_type = {
         .match = vio_bus_match,
         .probe = vio_bus_probe,
         .remove = vio_bus_remove,
+        .pm = &vio_dev_pm_ops,
 };
 
 /**