2 files changed, 40 insertions, 3 deletions

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index a2ebe199674..ca3751fd447 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -1313,6 +1313,11 @@ static int hid_suspend(struct usb_interface *intf, pm_message_t message)
 		{
 			set_bit(HID_REPORTED_IDLE, &usbhid->iofl);
 			spin_unlock_irq(&usbhid->lock);
+			if (hid->driver && hid->driver->suspend) {
+				status = hid->driver->suspend(hid, message);
+				if (status < 0)
+					return status;
+			}
 		} else {
 			usbhid_mark_busy(usbhid);
 			spin_unlock_irq(&usbhid->lock);
@@ -1320,6 +1325,11 @@ static int hid_suspend(struct usb_interface *intf, pm_message_t message)
 		}
 
 	} else {
+		if (hid->driver && hid->driver->suspend) {
+			status = hid->driver->suspend(hid, message);
+			if (status < 0)
+				return status;
+		}
 		spin_lock_irq(&usbhid->lock);
 		set_bit(HID_REPORTED_IDLE, &usbhid->iofl);
 		spin_unlock_irq(&usbhid->lock);
@@ -1374,6 +1384,11 @@ static int hid_resume(struct usb_interface *intf)
 		hid_io_error(hid);
 	usbhid_restart_queues(usbhid);
 
+	if (status >= 0 && hid->driver && hid->driver->resume) {
+		int ret = hid->driver->resume(hid);
+		if (ret < 0)
+			status = ret;
+	}
 	dev_dbg(&intf->dev, "resume status %d\n", status);
 	return 0;
 }
@@ -1382,9 +1397,16 @@ static int hid_reset_resume(struct usb_interface *intf)
 {
 	struct hid_device *hid = usb_get_intfdata(intf);
 	struct usbhid_device *usbhid = hid->driver_data;
+	int status;
 
 	clear_bit(HID_REPORTED_IDLE, &usbhid->iofl);
-	return hid_post_reset(intf);
+	status = hid_post_reset(intf);
+	if (status >= 0 && hid->driver && hid->driver->reset_resume) {
+		int ret = hid->driver->reset_resume(hid);
+		if (ret < 0)
+			status = ret;
+	}
+	return status;
 }
 
 #endif /* CONFIG_PM */
diff --git a/drivers/hid/usbhid/hiddev.c b/drivers/hid/usbhid/hiddev.c
index 433602aed46..c24d2fa3e3b 100644
--- a/drivers/hid/usbhid/hiddev.c
+++ b/drivers/hid/usbhid/hiddev.c
@@ -267,6 +267,7 @@ static int hiddev_open(struct inode *inode, struct file *file)
 	struct hiddev_list *list;
 	int res, i;
 
+	/* See comment in hiddev_connect() for BKL explanation */
 	lock_kernel();
 	i = iminor(inode) - HIDDEV_MINOR_BASE;
 
@@ -894,8 +895,22 @@ int hiddev_connect(struct hid_device *hid, unsigned int force)
 	hiddev->hid = hid;
 	hiddev->exist = 1;
 
-	/* when lock_kernel() usage is fixed in usb_open(),
-	 * we could also fix it here */
+	/*
+	 * BKL here is used to avoid race after usb_register_dev().
+	 * Once the device node has been created, open() could happen on it.
+	 * The code below will then fail, as hiddev_table hasn't been
+	 * updated.
+	 *
+	 * The obvious fix -- introducing mutex to guard hiddev_table[]
+	 * doesn't work, as usb_open() and usb_register_dev() both take
+	 * minor_rwsem, thus we'll have ABBA deadlock.
+	 *
+	 * Before BKL pushdown, usb_open() had been acquiring it in right
+	 * order, so _open() was safe to use it to protect from this race.
+	 * Now the order is different, but AB-BA deadlock still doesn't occur
+	 * as BKL is dropped on schedule() (i.e. while sleeping on
+	 * minor_rwsem). Fugly.
+	 */
 	lock_kernel();
 	retval = usb_register_dev(usbhid->intf, &hiddev_class);
 	if (retval) {