usbcore: non-hub-specific uses of autosuspend

This patch (as741) makes the non-hub parts of usbcore actually use the
autosuspend facilities added by an earlier patch.

	Devices opened through usbfs are autoresumed and then
	autosuspended upon close.

	Likewise for usb-skeleton.

	Devices are autoresumed for usb_set_configuration.


Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

4 files changed, 28 insertions, 11 deletions

diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
index 43c08724a2d8..fd345ad810f8 100644
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -558,10 +558,12 @@ static int usbdev_open(struct inode *inode, struct file *file)
                 dev = usbdev_lookup_minor(iminor(inode));
         if (!dev)
                 dev = inode->i_private;
-        if (!dev) {
-                kfree(ps);
+        if (!dev)
                 goto out;
-        }
+        ret = usb_autoresume_device(dev, 1);
+        if (ret)
+                goto out;
+
         usb_get_dev(dev);
         ret = 0;
         ps->dev = dev;
@@ -581,6 +583,8 @@ static int usbdev_open(struct inode *inode, struct file *file)
         list_add_tail(&ps->list, &dev->filelist);
         file->private_data = ps;
  out:
+        if (ret)
+                kfree(ps);
         mutex_unlock(&usbfs_mutex);
         return ret;
 }
@@ -604,6 +608,7 @@ static int usbdev_release(struct inode *inode, struct file *file)
                         releaseintf(ps, ifnum);
         }
         destroy_all_async(ps);
+        usb_autosuspend_device(dev, 1);
         usb_unlock_device(dev);
         usb_put_dev(dev);
         kfree(ps);
diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c
index 5358e656477c..16332cc57946 100644
--- a/drivers/usb/core/generic.c
+++ b/drivers/usb/core/generic.c
@@ -172,14 +172,10 @@ static void generic_disconnect(struct usb_device *udev)
 
         /* if this is only an unbind, not a physical disconnect, then
          * unconfigure the device */
-        if (udev->state == USB_STATE_CONFIGURED)
+        if (udev->actconfig)
                 usb_set_configuration(udev, 0);
 
         usb_remove_sysfs_dev_files(udev);
-
-        /* in case the call failed or the device was suspended */
-        if (udev->state >= USB_STATE_CONFIGURED)
-                usb_disable_device(udev, 0);
 }
 
 #ifdef  CONFIG_PM
@@ -208,4 +204,5 @@ struct usb_device_driver usb_generic_driver = {
         .suspend = generic_suspend,
         .resume = generic_resume,
 #endif
+        .supports_autosuspend = 1,
 };
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 1580c81a0db7..28c6cf225780 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1366,9 +1366,6 @@ int usb_set_configuration(struct usb_device *dev, int configuration)
         if (cp && configuration == 0)
                 dev_warn(&dev->dev, "config 0 descriptor??\n");
 
-        if (dev->state == USB_STATE_SUSPENDED)
-                return -EHOSTUNREACH;
-
         /* Allocate memory for new interfaces before doing anything else,
          * so that if we run out then nothing will have changed. */
         n = nintf = 0;
@@ -1403,6 +1400,11 @@ free_interfaces:
                                         configuration, -i);
         }
 
+        /* Wake up the device so we can send it the Set-Config request */
+        ret = usb_autoresume_device(dev, 1);
+        if (ret)
+                goto free_interfaces;
+
         /* if it's already configured, clear out old state first.
          * getting rid of old interfaces means unbinding their drivers.
          */
@@ -1422,6 +1424,7 @@ free_interfaces:
         dev->actconfig = cp;
         if (!cp) {
                 usb_set_device_state(dev, USB_STATE_ADDRESS);
+                usb_autosuspend_device(dev, 1);
                 goto free_interfaces;
         }
         usb_set_device_state(dev, USB_STATE_CONFIGURED);
@@ -1490,6 +1493,7 @@ free_interfaces:
                 usb_create_sysfs_intf_files (intf);
         }
 
+        usb_autosuspend_device(dev, 1);
         return 0;
 }
 
diff --git a/drivers/usb/usb-skeleton.c b/drivers/usb/usb-skeleton.c
index 9b542a6ba978..1b51d3187a95 100644
--- a/drivers/usb/usb-skeleton.c
+++ b/drivers/usb/usb-skeleton.c
@@ -90,6 +90,11 @@ static int skel_open(struct inode *inode, struct file *file)
                 goto exit;
         }
 
+        /* prevent the device from being autosuspended */
+        retval = usb_autopm_get_interface(interface);
+        if (retval)
+                goto exit;
+
         /* increment our usage count for the device */
         kref_get(&dev->kref);
 
@@ -108,6 +113,12 @@ static int skel_release(struct inode *inode, struct file *file)
         if (dev == NULL)
                 return -ENODEV;
 
+        /* allow the device to be autosuspended */
+        mutex_lock(&dev->io_mutex);
+        if (dev->interface)
+                usb_autopm_put_interface(dev->interface);
+        mutex_unlock(&dev->io_mutex);
+
         /* decrement the count on our device */
         kref_put(&dev->kref, skel_delete);
         return 0;