1 files changed, 934 insertions, 77 deletions

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index ec8906501415..b10463244413 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -17,7 +17,8 @@
  *
  * NOTE! This is not actually a driver at all, rather this is
  * just a collection of helper routines that implement the
- * generic USB things that the real drivers can use..
+ * matching, probing, releasing, suspending and resuming for
+ * real drivers.
  *
  */
 
@@ -34,38 +35,6 @@ struct usb_dynid {
 	struct usb_device_id id;
 };
 
-
-static int generic_probe(struct device *dev)
-{
-	return 0;
-}
-static int generic_remove(struct device *dev)
-{
-	struct usb_device *udev = to_usb_device(dev);
-
-	/* if this is only an unbind, not a physical disconnect, then
-	 * unconfigure the device */
-	if (udev->state == USB_STATE_CONFIGURED)
-		usb_set_configuration(udev, 0);
-
-	/* in case the call failed or the device was suspended */
-	if (udev->state >= USB_STATE_CONFIGURED)
-		usb_disable_device(udev, 0);
-	return 0;
-}
-
-struct device_driver usb_generic_driver = {
-	.owner = THIS_MODULE,
-	.name =	"usb",
-	.bus = &usb_bus_type,
-	.probe = generic_probe,
-	.remove = generic_remove,
-};
-
-/* Fun hack to determine if the struct device is a
- * usb device or a usb interface. */
-int usb_generic_driver_data;
-
 #ifdef CONFIG_HOTPLUG
 
 /*
@@ -80,6 +49,7 @@ static ssize_t store_new_id(struct device_driver *driver,
 	u32 idVendor = 0;
 	u32 idProduct = 0;
 	int fields = 0;
+	int retval = 0;
 
 	fields = sscanf(buf, "%x %x", &idVendor, &idProduct);
 	if (fields < 2)
@@ -99,10 +69,12 @@ static ssize_t store_new_id(struct device_driver *driver,
 	spin_unlock(&usb_drv->dynids.lock);
 
 	if (get_driver(driver)) {
-		driver_attach(driver);
+		retval = driver_attach(driver);
 		put_driver(driver);
 	}
 
+	if (retval)
+		return retval;
 	return count;
 }
 static DRIVER_ATTR(new_id, S_IWUSR, NULL, store_new_id);
@@ -115,7 +87,7 @@ static int usb_create_newid_file(struct usb_driver *usb_drv)
 		goto exit;
 
 	if (usb_drv->probe != NULL)
-		error = sysfs_create_file(&usb_drv->driver.kobj,
+		error = sysfs_create_file(&usb_drv->drvwrap.driver.kobj,
 					  &driver_attr_new_id.attr);
 exit:
 	return error;
@@ -127,7 +99,7 @@ static void usb_remove_newid_file(struct usb_driver *usb_drv)
 		return;
 
 	if (usb_drv->probe != NULL)
-		sysfs_remove_file(&usb_drv->driver.kobj,
+		sysfs_remove_file(&usb_drv->drvwrap.driver.kobj,
 				  &driver_attr_new_id.attr);
 }
 
@@ -174,21 +146,57 @@ static const struct usb_device_id *usb_match_dynamic_id(struct usb_interface *in
 }
 
 
-/* called from driver core with usb_bus_type.subsys writelock */
+/* called from driver core with dev locked */
+static int usb_probe_device(struct device *dev)
+{
+	struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
+	struct usb_device *udev;
+	int error = -ENODEV;
+
+	dev_dbg(dev, "%s\n", __FUNCTION__);
+
+	if (!is_usb_device(dev))	/* Sanity check */
+		return error;
+
+	udev = to_usb_device(dev);
+
+	/* TODO: Add real matching code */
+
+	/* The device should always appear to be in use
+	 * unless the driver suports autosuspend.
+	 */
+	udev->pm_usage_cnt = !(udriver->supports_autosuspend);
+
+	error = udriver->probe(udev);
+	return error;
+}
+
+/* called from driver core with dev locked */
+static int usb_unbind_device(struct device *dev)
+{
+	struct usb_device_driver *udriver = to_usb_device_driver(dev->driver);
+
+	udriver->disconnect(to_usb_device(dev));
+	return 0;
+}
+
+
+/* called from driver core with dev locked */
 static int usb_probe_interface(struct device *dev)
 {
-	struct usb_interface * intf = to_usb_interface(dev);
-	struct usb_driver * driver = to_usb_driver(dev->driver);
+	struct usb_driver *driver = to_usb_driver(dev->driver);
+	struct usb_interface *intf;
+	struct usb_device *udev;
 	const struct usb_device_id *id;
 	int error = -ENODEV;
 
 	dev_dbg(dev, "%s\n", __FUNCTION__);
 
-	if (!driver->probe)
+	if (is_usb_device(dev))		/* Sanity check */
 		return error;
-	/* FIXME we'd much prefer to just resume it ... */
-	if (interface_to_usbdev(intf)->state == USB_STATE_SUSPENDED)
-		return -EHOSTUNREACH;
+
+	intf = to_usb_interface(dev);
+	udev = interface_to_usbdev(intf);
 
 	id = usb_match_id(intf, driver->id_table);
 	if (!id)
@@ -196,48 +204,165 @@ static int usb_probe_interface(struct device *dev)
 	if (id) {
 		dev_dbg(dev, "%s - got id\n", __FUNCTION__);
 
+		error = usb_autoresume_device(udev, 1);
+		if (error)
+			return error;
+
 		/* Interface "power state" doesn't correspond to any hardware
 		 * state whatsoever.  We use it to record when it's bound to
 		 * a driver that may start I/0:  it's not frozen/quiesced.
 		 */
 		mark_active(intf);
 		intf->condition = USB_INTERFACE_BINDING;
+
+		/* The interface should always appear to be in use
+		 * unless the driver suports autosuspend.
+		 */
+		intf->pm_usage_cnt = !(driver->supports_autosuspend);
+
 		error = driver->probe(intf, id);
 		if (error) {
 			mark_quiesced(intf);
+			intf->needs_remote_wakeup = 0;
 			intf->condition = USB_INTERFACE_UNBOUND;
 		} else
 			intf->condition = USB_INTERFACE_BOUND;
+
+		usb_autosuspend_device(udev, 1);
 	}
 
 	return error;
 }
 
-/* called from driver core with usb_bus_type.subsys writelock */
+/* called from driver core with dev locked */
 static int usb_unbind_interface(struct device *dev)
 {
+	struct usb_driver *driver = to_usb_driver(dev->driver);
 	struct usb_interface *intf = to_usb_interface(dev);
-	struct usb_driver *driver = to_usb_driver(intf->dev.driver);
+	struct usb_device *udev;
+	int error;
 
 	intf->condition = USB_INTERFACE_UNBINDING;
 
+	/* Autoresume for set_interface call below */
+	udev = interface_to_usbdev(intf);
+	error = usb_autoresume_device(udev, 1);
+
 	/* release all urbs for this interface */
 	usb_disable_interface(interface_to_usbdev(intf), intf);
 
-	if (driver && driver->disconnect)
-		driver->disconnect(intf);
+	driver->disconnect(intf);
 
 	/* reset other interface state */
 	usb_set_interface(interface_to_usbdev(intf),
 			intf->altsetting[0].desc.bInterfaceNumber,
 			0);
 	usb_set_intfdata(intf, NULL);
+
 	intf->condition = USB_INTERFACE_UNBOUND;
 	mark_quiesced(intf);
+	intf->needs_remote_wakeup = 0;
+
+	if (!error)
+		usb_autosuspend_device(udev, 1);
 
 	return 0;
 }
 
+/**
+ * usb_driver_claim_interface - bind a driver to an interface
+ * @driver: the driver to be bound
+ * @iface: the interface to which it will be bound; must be in the
+ *	usb device's active configuration
+ * @priv: driver data associated with that interface
+ *
+ * This is used by usb device drivers that need to claim more than one
+ * interface on a device when probing (audio and acm are current examples).
+ * No device driver should directly modify internal usb_interface or
+ * usb_device structure members.
+ *
+ * Few drivers should need to use this routine, since the most natural
+ * way to bind to an interface is to return the private data from
+ * the driver's probe() method.
+ *
+ * Callers must own the device lock and the driver model's usb_bus_type.subsys
+ * writelock.  So driver probe() entries don't need extra locking,
+ * but other call contexts may need to explicitly claim those locks.
+ */
+int usb_driver_claim_interface(struct usb_driver *driver,
+				struct usb_interface *iface, void* priv)
+{
+	struct device *dev = &iface->dev;
+	struct usb_device *udev = interface_to_usbdev(iface);
+	int retval = 0;
+
+	if (dev->driver)
+		return -EBUSY;
+
+	dev->driver = &driver->drvwrap.driver;
+	usb_set_intfdata(iface, priv);
+
+	mutex_lock_nested(&udev->pm_mutex, udev->level);
+	iface->condition = USB_INTERFACE_BOUND;
+	mark_active(iface);
+	iface->pm_usage_cnt = !(driver->supports_autosuspend);
+	mutex_unlock(&udev->pm_mutex);
+
+	/* if interface was already added, bind now; else let
+	 * the future device_add() bind it, bypassing probe()
+	 */
+	if (device_is_registered(dev))
+		retval = device_bind_driver(dev);
+
+	return retval;
+}
+EXPORT_SYMBOL(usb_driver_claim_interface);
+
+/**
+ * usb_driver_release_interface - unbind a driver from an interface
+ * @driver: the driver to be unbound
+ * @iface: the interface from which it will be unbound
+ *
+ * This can be used by drivers to release an interface without waiting
+ * for their disconnect() methods to be called.  In typical cases this
+ * also causes the driver disconnect() method to be called.
+ *
+ * This call is synchronous, and may not be used in an interrupt context.
+ * Callers must own the device lock and the driver model's usb_bus_type.subsys
+ * writelock.  So driver disconnect() entries don't need extra locking,
+ * but other call contexts may need to explicitly claim those locks.
+ */
+void usb_driver_release_interface(struct usb_driver *driver,
+					struct usb_interface *iface)
+{
+	struct device *dev = &iface->dev;
+	struct usb_device *udev = interface_to_usbdev(iface);
+
+	/* this should never happen, don't release something that's not ours */
+	if (!dev->driver || dev->driver != &driver->drvwrap.driver)
+		return;
+
+	/* don't release from within disconnect() */
+	if (iface->condition != USB_INTERFACE_BOUND)
+		return;
+
+	/* don't release if the interface hasn't been added yet */
+	if (device_is_registered(dev)) {
+		iface->condition = USB_INTERFACE_UNBINDING;
+		device_release_driver(dev);
+	}
+
+	dev->driver = NULL;
+	usb_set_intfdata(iface, NULL);
+
+	mutex_lock_nested(&udev->pm_mutex, udev->level);
+	iface->condition = USB_INTERFACE_UNBOUND;
+	mark_quiesced(iface);
+	iface->needs_remote_wakeup = 0;
+	mutex_unlock(&udev->pm_mutex);
+}
+EXPORT_SYMBOL(usb_driver_release_interface);
+
 /* returns 0 if no match, 1 if match */
 static int usb_match_one_id(struct usb_interface *interface,
 			    const struct usb_device_id *id)
@@ -381,35 +506,223 @@ EXPORT_SYMBOL_GPL_FUTURE(usb_match_id);
 
 int usb_device_match(struct device *dev, struct device_driver *drv)
 {
+	/* devices and interfaces are handled separately */
+	if (is_usb_device(dev)) {
+
+		/* interface drivers never match devices */
+		if (!is_usb_device_driver(drv))
+			return 0;
+
+		/* TODO: Add real matching code */
+		return 1;
+
+	} else {
+		struct usb_interface *intf;
+		struct usb_driver *usb_drv;
+		const struct usb_device_id *id;
+
+		/* device drivers never match interfaces */
+		if (is_usb_device_driver(drv))
+			return 0;
+
+		intf = to_usb_interface(dev);
+		usb_drv = to_usb_driver(drv);
+
+		id = usb_match_id(intf, usb_drv->id_table);
+		if (id)
+			return 1;
+
+		id = usb_match_dynamic_id(intf, usb_drv);
+		if (id)
+			return 1;
+	}
+
+	return 0;
+}
+
+#ifdef	CONFIG_HOTPLUG
+
+/*
+ * This sends an uevent to userspace, typically helping to load driver
+ * or other modules, configure the device, and more.  Drivers can provide
+ * a MODULE_DEVICE_TABLE to help with module loading subtasks.
+ *
+ * We're called either from khubd (the typical case) or from root hub
+ * (init, kapmd, modprobe, rmmod, etc), but the agents need to handle
+ * delays in event delivery.  Use sysfs (and DEVPATH) to make sure the
+ * device (and this configuration!) are still present.
+ */
+static int usb_uevent(struct device *dev, char **envp, int num_envp,
+		      char *buffer, int buffer_size)
+{
 	struct usb_interface *intf;
-	struct usb_driver *usb_drv;
-	const struct usb_device_id *id;
+	struct usb_device *usb_dev;
+	struct usb_host_interface *alt;
+	int i = 0;
+	int length = 0;
 
-	/* check for generic driver, which we don't match any device with */
-	if (drv == &usb_generic_driver)
-		return 0;
+	if (!dev)
+		return -ENODEV;
 
-	intf = to_usb_interface(dev);
-	usb_drv = to_usb_driver(drv);
+	/* driver is often null here; dev_dbg() would oops */
+	pr_debug ("usb %s: uevent\n", dev->bus_id);
 
-	id = usb_match_id(intf, usb_drv->id_table);
-	if (id)
-		return 1;
+	if (is_usb_device(dev)) {
+		usb_dev = to_usb_device(dev);
+		alt = NULL;
+	} else {
+		intf = to_usb_interface(dev);
+		usb_dev = interface_to_usbdev(intf);
+		alt = intf->cur_altsetting;
+	}
+
+	if (usb_dev->devnum < 0) {
+		pr_debug ("usb %s: already deleted?\n", dev->bus_id);
+		return -ENODEV;
+	}
+	if (!usb_dev->bus) {
+		pr_debug ("usb %s: bus removed?\n", dev->bus_id);
+		return -ENODEV;
+	}
+
+#ifdef	CONFIG_USB_DEVICEFS
+	/* If this is available, userspace programs can directly read
+	 * all the device descriptors we don't tell them about.  Or
+	 * even act as usermode drivers.
+	 *
+	 * FIXME reduce hardwired intelligence here
+	 */
+	if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "DEVICE=/proc/bus/usb/%03d/%03d",
+			   usb_dev->bus->busnum, usb_dev->devnum))
+		return -ENOMEM;
+#endif
+
+	/* per-device configurations are common */
+	if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "PRODUCT=%x/%x/%x",
+			   le16_to_cpu(usb_dev->descriptor.idVendor),
+			   le16_to_cpu(usb_dev->descriptor.idProduct),
+			   le16_to_cpu(usb_dev->descriptor.bcdDevice)))
+		return -ENOMEM;
+
+	/* class-based driver binding models */
+	if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "TYPE=%d/%d/%d",
+			   usb_dev->descriptor.bDeviceClass,
+			   usb_dev->descriptor.bDeviceSubClass,
+			   usb_dev->descriptor.bDeviceProtocol))
+		return -ENOMEM;
+
+	if (!is_usb_device(dev)) {
+
+		if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "INTERFACE=%d/%d/%d",
+			   alt->desc.bInterfaceClass,
+			   alt->desc.bInterfaceSubClass,
+			   alt->desc.bInterfaceProtocol))
+			return -ENOMEM;
+
+		if (add_uevent_var(envp, num_envp, &i,
+			   buffer, buffer_size, &length,
+			   "MODALIAS=usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
+			   le16_to_cpu(usb_dev->descriptor.idVendor),
+			   le16_to_cpu(usb_dev->descriptor.idProduct),
+			   le16_to_cpu(usb_dev->descriptor.bcdDevice),
+			   usb_dev->descriptor.bDeviceClass,
+			   usb_dev->descriptor.bDeviceSubClass,
+			   usb_dev->descriptor.bDeviceProtocol,
+			   alt->desc.bInterfaceClass,
+			   alt->desc.bInterfaceSubClass,
+			   alt->desc.bInterfaceProtocol))
+			return -ENOMEM;
+	}
+
+	envp[i] = NULL;
 
-	id = usb_match_dynamic_id(intf, usb_drv);
-	if (id)
-		return 1;
 	return 0;
 }
 
+#else
+
+static int usb_uevent(struct device *dev, char **envp,
+			int num_envp, char *buffer, int buffer_size)
+{
+	return -ENODEV;
+}
+
+#endif	/* CONFIG_HOTPLUG */
+
+/**
+ * usb_register_device_driver - register a USB device (not interface) driver
+ * @new_udriver: USB operations for the device driver
+ * @owner: module owner of this driver.
+ *
+ * Registers a USB device driver with the USB core.  The list of
+ * unattached devices will be rescanned whenever a new driver is
+ * added, allowing the new driver to attach to any recognized devices.
+ * Returns a negative error code on failure and 0 on success.
+ */
+int usb_register_device_driver(struct usb_device_driver *new_udriver,
+		struct module *owner)
+{
+	int retval = 0;
+
+	if (usb_disabled())
+		return -ENODEV;
+
+	new_udriver->drvwrap.for_devices = 1;
+	new_udriver->drvwrap.driver.name = (char *) new_udriver->name;
+	new_udriver->drvwrap.driver.bus = &usb_bus_type;
+	new_udriver->drvwrap.driver.probe = usb_probe_device;
+	new_udriver->drvwrap.driver.remove = usb_unbind_device;
+	new_udriver->drvwrap.driver.owner = owner;
+
+	retval = driver_register(&new_udriver->drvwrap.driver);
+
+	if (!retval) {
+		pr_info("%s: registered new device driver %s\n",
+			usbcore_name, new_udriver->name);
+		usbfs_update_special();
+	} else {
+		printk(KERN_ERR "%s: error %d registering device "
+			"	driver %s\n",
+			usbcore_name, retval, new_udriver->name);
+	}
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(usb_register_device_driver);
+
+/**
+ * usb_deregister_device_driver - unregister a USB device (not interface) driver
+ * @udriver: USB operations of the device driver to unregister
+ * Context: must be able to sleep
+ *
+ * Unlinks the specified driver from the internal USB driver list.
+ */
+void usb_deregister_device_driver(struct usb_device_driver *udriver)
+{
+	pr_info("%s: deregistering device driver %s\n",
+			usbcore_name, udriver->name);
+
+	driver_unregister(&udriver->drvwrap.driver);
+	usbfs_update_special();
+}
+EXPORT_SYMBOL_GPL(usb_deregister_device_driver);
+
 /**
- * usb_register_driver - register a USB driver
- * @new_driver: USB operations for the driver
+ * usb_register_driver - register a USB interface driver
+ * @new_driver: USB operations for the interface driver
  * @owner: module owner of this driver.
  *
- * Registers a USB driver with the USB core.  The list of unattached
- * interfaces will be rescanned whenever a new driver is added, allowing
- * the new driver to attach to any recognized devices.
+ * Registers a USB interface driver with the USB core.  The list of
+ * unattached interfaces will be rescanned whenever a new driver is
+ * added, allowing the new driver to attach to any recognized interfaces.
  * Returns a negative error code on failure and 0 on success.
  *
  * NOTE: if you want your driver to use the USB major number, you must call
@@ -423,23 +736,25 @@ int usb_register_driver(struct usb_driver *new_driver, struct module *owner)
 	if (usb_disabled())
 		return -ENODEV;
 
-	new_driver->driver.name = (char *)new_driver->name;
-	new_driver->driver.bus = &usb_bus_type;
-	new_driver->driver.probe = usb_probe_interface;
-	new_driver->driver.remove = usb_unbind_interface;
-	new_driver->driver.owner = owner;
+	new_driver->drvwrap.for_devices = 0;
+	new_driver->drvwrap.driver.name = (char *) new_driver->name;
+	new_driver->drvwrap.driver.bus = &usb_bus_type;
+	new_driver->drvwrap.driver.probe = usb_probe_interface;
+	new_driver->drvwrap.driver.remove = usb_unbind_interface;
+	new_driver->drvwrap.driver.owner = owner;
 	spin_lock_init(&new_driver->dynids.lock);
 	INIT_LIST_HEAD(&new_driver->dynids.list);
 
-	retval = driver_register(&new_driver->driver);
+	retval = driver_register(&new_driver->drvwrap.driver);
 
 	if (!retval) {
-		pr_info("%s: registered new driver %s\n",
+		pr_info("%s: registered new interface driver %s\n",
 			usbcore_name, new_driver->name);
 		usbfs_update_special();
 		usb_create_newid_file(new_driver);
 	} else {
-		printk(KERN_ERR "%s: error %d registering driver %s\n",
+		printk(KERN_ERR "%s: error %d registering interface "
+			"	driver %s\n",
 			usbcore_name, retval, new_driver->name);
 	}
 
@@ -448,8 +763,8 @@ int usb_register_driver(struct usb_driver *new_driver, struct module *owner)
 EXPORT_SYMBOL_GPL_FUTURE(usb_register_driver);
 
 /**
- * usb_deregister - unregister a USB driver
- * @driver: USB operations of the driver to unregister
+ * usb_deregister - unregister a USB interface driver
+ * @driver: USB operations of the interface driver to unregister
  * Context: must be able to sleep
  *
  * Unlinks the specified driver from the internal USB driver list.
@@ -460,12 +775,554 @@ EXPORT_SYMBOL_GPL_FUTURE(usb_register_driver);
  */
 void usb_deregister(struct usb_driver *driver)
 {
-	pr_info("%s: deregistering driver %s\n", usbcore_name, driver->name);
+	pr_info("%s: deregistering interface driver %s\n",
+			usbcore_name, driver->name);
 
 	usb_remove_newid_file(driver);
 	usb_free_dynids(driver);
-	driver_unregister(&driver->driver);
+	driver_unregister(&driver->drvwrap.driver);
 
 	usbfs_update_special();
 }
 EXPORT_SYMBOL_GPL_FUTURE(usb_deregister);
+
+#ifdef CONFIG_PM
+
+/* Caller has locked udev->pm_mutex */
+static int suspend_device(struct usb_device *udev, pm_message_t msg)
+{
+	struct usb_device_driver	*udriver;
+	int				status = 0;
+
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			udev->state == USB_STATE_SUSPENDED)
+		goto done;
+
+	/* For devices that don't have a driver, we do a standard suspend. */
+	if (udev->dev.driver == NULL) {
+		udev->do_remote_wakeup = 0;
+		status = usb_port_suspend(udev);
+		goto done;
+	}
+
+	udriver = to_usb_device_driver(udev->dev.driver);
+	status = udriver->suspend(udev, msg);
+
+done:
+	// dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
+	if (status == 0)
+		udev->dev.power.power_state.event = msg.event;
+	return status;
+}
+
+/* Caller has locked udev->pm_mutex */
+static int resume_device(struct usb_device *udev)
+{
+	struct usb_device_driver	*udriver;
+	int				status = 0;
+
+	if (udev->state == USB_STATE_NOTATTACHED ||
+			udev->state != USB_STATE_SUSPENDED)
+		goto done;
+
+	/* Can't resume it if it doesn't have a driver. */
+	if (udev->dev.driver == NULL) {
+		status = -ENOTCONN;
+		goto done;
+	}
+
+	udriver = to_usb_device_driver(udev->dev.driver);
+	status = udriver->resume(udev);
+
+done:
+	// dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
+	if (status == 0)
+		udev->dev.power.power_state.event = PM_EVENT_ON;
+	return status;
+}
+
+/* Caller has locked intf's usb_device's pm_mutex */
+static int suspend_interface(struct usb_interface *intf, pm_message_t msg)
+{
+	struct usb_driver	*driver;
+	int			status = 0;
+
+	/* with no hardware, USB interfaces only use FREEZE and ON states */
+	if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
+			!is_active(intf))
+		goto done;
+
+	if (intf->condition == USB_INTERFACE_UNBOUND)	/* This can't happen */
+		goto done;
+	driver = to_usb_driver(intf->dev.driver);
+
+	if (driver->suspend && driver->resume) {
+		status = driver->suspend(intf, msg);
+		if (status == 0)
+			mark_quiesced(intf);
+		else if (!interface_to_usbdev(intf)->auto_pm)
+			dev_err(&intf->dev, "%s error %d\n",
+					"suspend", status);
+	} else {
+		// FIXME else if there's no suspend method, disconnect...
+		// Not possible if auto_pm is set...
+		dev_warn(&intf->dev, "no suspend for driver %s?\n",
+				driver->name);
+		mark_quiesced(intf);
+	}
+
+done:
+	// dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
+	if (status == 0)
+		intf->dev.power.power_state.event = msg.event;
+	return status;
+}
+
+/* Caller has locked intf's usb_device's pm_mutex */
+static int resume_interface(struct usb_interface *intf)
+{
+	struct usb_driver	*driver;
+	int			status = 0;
+
+	if (interface_to_usbdev(intf)->state == USB_STATE_NOTATTACHED ||
+			is_active(intf))
+		goto done;
+
+	/* Don't let autoresume interfere with unbinding */
+	if (intf->condition == USB_INTERFACE_UNBINDING)
+		goto done;
+
+	/* Can't resume it if it doesn't have a driver. */
+	if (intf->condition == USB_INTERFACE_UNBOUND) {
+		status = -ENOTCONN;
+		goto done;
+	}
+	driver = to_usb_driver(intf->dev.driver);
+
+	if (driver->resume) {
+		status = driver->resume(intf);
+		if (status)
+			dev_err(&intf->dev, "%s error %d\n",
+					"resume", status);
+		else
+			mark_active(intf);
+	} else {
+		dev_warn(&intf->dev, "no resume for driver %s?\n",
+				driver->name);
+		mark_active(intf);
+	}
+
+done:
+	// dev_dbg(&intf->dev, "%s: status %d\n", __FUNCTION__, status);
+	if (status == 0)
+		intf->dev.power.power_state.event = PM_EVENT_ON;
+	return status;
+}
+
+/**
+ * usb_suspend_both - suspend a USB device and its interfaces
+ * @udev: the usb_device to suspend
+ * @msg: Power Management message describing this state transition
+ *
+ * This is the central routine for suspending USB devices.  It calls the
+ * suspend methods for all the interface drivers in @udev and then calls
+ * the suspend method for @udev itself.  If an error occurs at any stage,
+ * all the interfaces which were suspended are resumed so that they remain
+ * in the same state as the device.
+ *
+ * If an autosuspend is in progress (@udev->auto_pm is set), the routine
+ * checks first to make sure that neither the device itself or any of its
+ * active interfaces is in use (pm_usage_cnt is greater than 0).  If they
+ * are, the autosuspend fails.
+ *
+ * If the suspend succeeds, the routine recursively queues an autosuspend
+ * request for @udev's parent device, thereby propagating the change up
+ * the device tree.  If all of the parent's children are now suspended,
+ * the parent will autosuspend in turn.
+ *
+ * The suspend method calls are subject to mutual exclusion under control
+ * of @udev's pm_mutex.  Many of these calls are also under the protection
+ * of @udev's device lock (including all requests originating outside the
+ * USB subsystem), but autosuspend requests generated by a child device or
+ * interface driver may not be.  Usbcore will insure that the method calls
+ * do not arrive during bind, unbind, or reset operations.  However, drivers
+ * must be prepared to handle suspend calls arriving at unpredictable times.
+ * The only way to block such calls is to do an autoresume (preventing
+ * autosuspends) while holding @udev's device lock (preventing outside
+ * suspends).
+ *
+ * The caller must hold @udev->pm_mutex.
+ *
+ * This routine can run only in process context.
+ */
+int usb_suspend_both(struct usb_device *udev, pm_message_t msg)
+{
+	int			status = 0;
+	int			i = 0;
+	struct usb_interface	*intf;
+	struct usb_device	*parent = udev->parent;
+
+	cancel_delayed_work(&udev->autosuspend);
+	if (udev->state == USB_STATE_NOTATTACHED)
+		return 0;
+	if (udev->state == USB_STATE_SUSPENDED)
+		return 0;
+
+	udev->do_remote_wakeup = device_may_wakeup(&udev->dev);
+
+	/* For autosuspend, fail fast if anything is in use.
+	 * Also fail if any interfaces require remote wakeup but it
+	 * isn't available. */
+	if (udev->auto_pm) {
+		if (udev->pm_usage_cnt > 0)
+			return -EBUSY;
+		if (udev->actconfig) {
+			for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
+				intf = udev->actconfig->interface[i];
+				if (!is_active(intf))
+					continue;
+				if (intf->pm_usage_cnt > 0)
+					return -EBUSY;
+				if (intf->needs_remote_wakeup &&
+						!udev->do_remote_wakeup) {
+					dev_dbg(&udev->dev,
+	"remote wakeup needed for autosuspend\n");
+					return -EOPNOTSUPP;
+				}
+			}
+			i = 0;
+		}
+	}
+
+	/* Suspend all the interfaces and then udev itself */
+	if (udev->actconfig) {
+		for (; i < udev->actconfig->desc.bNumInterfaces; i++) {
+			intf = udev->actconfig->interface[i];
+			status = suspend_interface(intf, msg);
+			if (status != 0)
+				break;
+		}
+	}
+	if (status == 0)
+		status = suspend_device(udev, msg);
+
+	/* If the suspend failed, resume interfaces that did get suspended */
+	if (status != 0) {
+		while (--i >= 0) {
+			intf = udev->actconfig->interface[i];
+			resume_interface(intf);
+		}
+
+	/* If the suspend succeeded, propagate it up the tree */
+	} else if (parent)
+		usb_autosuspend_device(parent, 0);
+
+	// dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
+	return status;
+}
+
+/**
+ * usb_resume_both - resume a USB device and its interfaces
+ * @udev: the usb_device to resume
+ *
+ * This is the central routine for resuming USB devices.  It calls the
+ * the resume method for @udev and then calls the resume methods for all
+ * the interface drivers in @udev.
+ *
+ * Before starting the resume, the routine calls itself recursively for
+ * the parent device of @udev, thereby propagating the change up the device
+ * tree and assuring that @udev will be able to resume.  If the parent is
+ * unable to resume successfully, the routine fails.
+ *
+ * The resume method calls are subject to mutual exclusion under control
+ * of @udev's pm_mutex.  Many of these calls are also under the protection
+ * of @udev's device lock (including all requests originating outside the
+ * USB subsystem), but autoresume requests generated by a child device or
+ * interface driver may not be.  Usbcore will insure that the method calls
+ * do not arrive during bind, unbind, or reset operations.  However, drivers
+ * must be prepared to handle resume calls arriving at unpredictable times.
+ * The only way to block such calls is to do an autoresume (preventing
+ * other autoresumes) while holding @udev's device lock (preventing outside
+ * resumes).
+ *
+ * The caller must hold @udev->pm_mutex.
+ *
+ * This routine can run only in process context.
+ */
+int usb_resume_both(struct usb_device *udev)
+{
+	int			status = 0;
+	int			i;
+	struct usb_interface	*intf;
+	struct usb_device	*parent = udev->parent;
+
+	cancel_delayed_work(&udev->autosuspend);
+	if (udev->state == USB_STATE_NOTATTACHED)
+		return -ENODEV;
+
+	/* Propagate the resume up the tree, if necessary */
+	if (udev->state == USB_STATE_SUSPENDED) {
+		if (parent) {
+			mutex_lock_nested(&parent->pm_mutex, parent->level);
+			parent->auto_pm = 1;
+			status = usb_resume_both(parent);
+		} else {
+
+			/* We can't progagate beyond the USB subsystem,
+			 * so if a root hub's controller is suspended
+			 * then we're stuck. */
+			if (udev->dev.parent->power.power_state.event !=
+					PM_EVENT_ON)
+				status = -EHOSTUNREACH;
+		}
+		if (status == 0)
+			status = resume_device(udev);
+		if (parent)
+			mutex_unlock(&parent->pm_mutex);
+	} else {
+
+		/* Needed only for setting udev->dev.power.power_state.event
+		 * and for possible debugging message. */
+		status = resume_device(udev);
+	}
+
+	/* Now the parent won't suspend until we are finished */
+
+	if (status == 0 && udev->actconfig) {
+		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
+			intf = udev->actconfig->interface[i];
+			resume_interface(intf);
+		}
+	}
+
+	// dev_dbg(&udev->dev, "%s: status %d\n", __FUNCTION__, status);
+	return status;
+}
+
+#ifdef CONFIG_USB_SUSPEND
+
+/**
+ * usb_autosuspend_device - delayed autosuspend of a USB device and its interfaces
+ * @udev - the usb_device to autosuspend
+ * @dec_usage_cnt - flag to decrement @udev's PM-usage counter
+ *
+ * This routine should be called when a core subsystem is finished using
+ * @udev and wants to allow it to autosuspend.  Examples would be when
+ * @udev's device file in usbfs is closed or after a configuration change.
+ *
+ * @dec_usage_cnt should be 1 if the subsystem previously incremented
+ * @udev's usage counter (such as by passing 1 to usb_autoresume_device);
+ * otherwise it should be 0.
+ *
+ * If the usage counter for @udev or any of its active interfaces is greater
+ * than 0, the autosuspend request will not be queued.  (If an interface
+ * driver does not support autosuspend then its usage counter is permanently
+ * positive.)  Likewise, if an interface driver requires remote-wakeup
+ * capability during autosuspend but remote wakeup is disabled, the
+ * autosuspend will fail.
+ *
+ * Often the caller will hold @udev's device lock, but this is not
+ * necessary.
+ *
+ * This routine can run only in process context.
+ */
+void usb_autosuspend_device(struct usb_device *udev, int dec_usage_cnt)
+{
+	mutex_lock_nested(&udev->pm_mutex, udev->level);
+	udev->pm_usage_cnt -= dec_usage_cnt;
+	if (udev->pm_usage_cnt <= 0)
+		schedule_delayed_work(&udev->autosuspend,
+				USB_AUTOSUSPEND_DELAY);
+	mutex_unlock(&udev->pm_mutex);
+	// dev_dbg(&udev->dev, "%s: cnt %d\n",
+	//		__FUNCTION__, udev->pm_usage_cnt);
+}
+
+/**
+ * usb_autoresume_device - immediately autoresume a USB device and its interfaces
+ * @udev - the usb_device to autoresume
+ * @inc_usage_cnt - flag to increment @udev's PM-usage counter
+ *
+ * This routine should be called when a core subsystem wants to use @udev
+ * and needs to guarantee that it is not suspended.  In addition, the
+ * caller can prevent @udev from being autosuspended subsequently.  (Note
+ * that this will not prevent suspend events originating in the PM core.)
+ * Examples would be when @udev's device file in usbfs is opened (autosuspend
+ * should be prevented until the file is closed) or when a remote-wakeup
+ * request is received (later autosuspends should not be prevented).
+ *
+ * @inc_usage_cnt should be 1 to increment @udev's usage counter and prevent
+ * autosuspends.  This prevention will persist until the usage counter is
+ * decremented again (such as by passing 1 to usb_autosuspend_device).
+ * Otherwise @inc_usage_cnt should be 0 to leave the usage counter unchanged.
+ * Regardless, if the autoresume fails then the usage counter is not
+ * incremented.
+ *
+ * Often the caller will hold @udev's device lock, but this is not
+ * necessary (and attempting it might cause deadlock).
+ *
+ * This routine can run only in process context.
+ */
+int usb_autoresume_device(struct usb_device *udev, int inc_usage_cnt)
+{
+	int	status;
+
+	mutex_lock_nested(&udev->pm_mutex, udev->level);
+	udev->pm_usage_cnt += inc_usage_cnt;
+	udev->auto_pm = 1;
+	status = usb_resume_both(udev);
+	if (status != 0)
+		udev->pm_usage_cnt -= inc_usage_cnt;
+	mutex_unlock(&udev->pm_mutex);
+	// dev_dbg(&udev->dev, "%s: status %d cnt %d\n",
+	//		__FUNCTION__, status, udev->pm_usage_cnt);
+	return status;
+}
+
+/**
+ * usb_autopm_put_interface - decrement a USB interface's PM-usage counter
+ * @intf - the usb_interface whose counter should be decremented
+ *
+ * This routine should be called by an interface driver when it is
+ * finished using @intf and wants to allow it to autosuspend.  A typical
+ * example would be a character-device driver when its device file is
+ * closed.
+ *
+ * The routine decrements @intf's usage counter.  When the counter reaches
+ * 0, a delayed autosuspend request for @intf's device is queued.  When
+ * the delay expires, if @intf->pm_usage_cnt is still <= 0 along with all
+ * the other usage counters for the sibling interfaces and @intf's
+ * usb_device, the device and all its interfaces will be autosuspended.
+ *
+ * Note that @intf->pm_usage_cnt is owned by the interface driver.  The
+ * core will not change its value other than the increment and decrement
+ * in usb_autopm_get_interface and usb_autopm_put_interface.  The driver
+ * may use this simple counter-oriented discipline or may set the value
+ * any way it likes.
+ *
+ * If the driver has set @intf->needs_remote_wakeup then autosuspend will
+ * take place only if the device's remote-wakeup facility is enabled.
+ *
+ * Suspend method calls queued by this routine can arrive at any time
+ * while @intf is resumed and its usage counter is equal to 0.  They are
+ * not protected by the usb_device's lock but only by its pm_mutex.
+ * Drivers must provide their own synchronization.
+ *
+ * This routine can run only in process context.
+ */
+void usb_autopm_put_interface(struct usb_interface *intf)
+{
+	struct usb_device	*udev = interface_to_usbdev(intf);
+
+	mutex_lock_nested(&udev->pm_mutex, udev->level);
+	if (intf->condition != USB_INTERFACE_UNBOUND) {
+		if (--intf->pm_usage_cnt <= 0)
+			schedule_delayed_work(&udev->autosuspend,
+					USB_AUTOSUSPEND_DELAY);
+	}
+	mutex_unlock(&udev->pm_mutex);
+	// dev_dbg(&intf->dev, "%s: cnt %d\n",
+	//		__FUNCTION__, intf->pm_usage_cnt);
+}
+EXPORT_SYMBOL_GPL(usb_autopm_put_interface);
+
+/**
+ * usb_autopm_get_interface - increment a USB interface's PM-usage counter
+ * @intf - the usb_interface whose counter should be incremented
+ *
+ * This routine should be called by an interface driver when it wants to
+ * use @intf and needs to guarantee that it is not suspended.  In addition,
+ * the routine prevents @intf from being autosuspended subsequently.  (Note
+ * that this will not prevent suspend events originating in the PM core.)
+ * This prevention will persist until usb_autopm_put_interface() is called
+ * or @intf is unbound.  A typical example would be a character-device
+ * driver when its device file is opened.
+ *
+ * The routine increments @intf's usage counter.  So long as the counter
+ * is greater than 0, autosuspend will not be allowed for @intf or its
+ * usb_device.  When the driver is finished using @intf it should call
+ * usb_autopm_put_interface() to decrement the usage counter and queue
+ * a delayed autosuspend request (if the counter is <= 0).
+ *
+ * Note that @intf->pm_usage_cnt is owned by the interface driver.  The
+ * core will not change its value other than the increment and decrement
+ * in usb_autopm_get_interface and usb_autopm_put_interface.  The driver
+ * may use this simple counter-oriented discipline or may set the value
+ * any way it likes.
+ *
+ * Resume method calls generated by this routine can arrive at any time
+ * while @intf is suspended.  They are not protected by the usb_device's
+ * lock but only by its pm_mutex.  Drivers must provide their own
+ * synchronization.
+ *
+ * This routine can run only in process context.
+ */
+int usb_autopm_get_interface(struct usb_interface *intf)
+{
+	struct usb_device	*udev = interface_to_usbdev(intf);
+	int			status;
+
+	mutex_lock_nested(&udev->pm_mutex, udev->level);
+	if (intf->condition == USB_INTERFACE_UNBOUND)
+		status = -ENODEV;
+	else {
+		++intf->pm_usage_cnt;
+		udev->auto_pm = 1;
+		status = usb_resume_both(udev);
+		if (status != 0)
+			--intf->pm_usage_cnt;
+	}
+	mutex_unlock(&udev->pm_mutex);
+	// dev_dbg(&intf->dev, "%s: status %d cnt %d\n",
+	//		__FUNCTION__, status, intf->pm_usage_cnt);
+	return status;
+}
+EXPORT_SYMBOL_GPL(usb_autopm_get_interface);
+
+#endif /* CONFIG_USB_SUSPEND */
+
+static int usb_suspend(struct device *dev, pm_message_t message)
+{
+	int	status;
+
+	if (is_usb_device(dev)) {
+		struct usb_device *udev = to_usb_device(dev);
+
+		mutex_lock_nested(&udev->pm_mutex, udev->level);
+		udev->auto_pm = 0;
+		status = usb_suspend_both(udev, message);
+		mutex_unlock(&udev->pm_mutex);
+	} else
+		status = 0;
+	return status;
+}
+
+static int usb_resume(struct device *dev)
+{
+	int	status;
+
+	if (is_usb_device(dev)) {
+		struct usb_device *udev = to_usb_device(dev);
+
+		mutex_lock_nested(&udev->pm_mutex, udev->level);
+		udev->auto_pm = 0;
+		status = usb_resume_both(udev);
+		mutex_unlock(&udev->pm_mutex);
+
+		/* Rebind drivers that had no suspend method? */
+	} else
+		status = 0;
+	return status;
+}
+
+#endif /* CONFIG_PM */
+
+struct bus_type usb_bus_type = {
+	.name =		"usb",
+	.match =	usb_device_match,
+	.uevent =	usb_uevent,
+#ifdef CONFIG_PM
+	.suspend =	usb_suspend,
+	.resume =	usb_resume,
+#endif
+};