+
+ // 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);