virtio-pci: move freeze/restore to virtio core

[cascardo/linux.git] / drivers / virtio / virtio.c

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 3980687..8216b73 100644 (file)
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -248,6 +248,60 @@ void virtio_config_changed(struct virtio_device *dev)
 }
 EXPORT_SYMBOL_GPL(virtio_config_changed);
 
+#ifdef CONFIG_PM_SLEEP
+int virtio_device_freeze(struct virtio_device *dev)
+{
+       struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+
+       dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
+
+       if (drv && drv->freeze)
+               return drv->freeze(dev);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_device_freeze);
+
+int virtio_device_restore(struct virtio_device *dev)
+{
+       struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+
+       /* We always start by resetting the device, in case a previous
+        * driver messed it up. */
+       dev->config->reset(dev);
+
+       /* Acknowledge that we've seen the device. */
+       add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+
+       /* Maybe driver failed before freeze.
+        * Restore the failed status, for debugging. */
+       if (dev->failed)
+               add_status(dev, VIRTIO_CONFIG_S_FAILED);
+
+       if (!drv)
+               return 0;
+
+       /* We have a driver! */
+       add_status(dev, VIRTIO_CONFIG_S_DRIVER);
+
+       dev->config->finalize_features(dev);
+
+       if (drv->restore) {
+               int ret = drv->restore(dev);
+               if (ret) {
+                       add_status(dev, VIRTIO_CONFIG_S_FAILED);
+                       return ret;
+               }
+       }
+
+       /* Finally, tell the device we're all set */
+       add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(virtio_device_restore);
+#endif
+
 static int virtio_init(void)
 {
        if (bus_register(&virtio_bus) != 0)