1 files changed, 17 insertions, 12 deletions

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 1673e5d08926..4d59d927ae3e 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1039,35 +1039,40 @@ char *usb_cache_string(struct usb_device *udev, int index)
 }
 
 /*
- * usb_get_device_descriptor - read the device descriptor
- * @udev: the device whose device descriptor should be read
+ * usb_get_device_descriptor - (re)reads the device descriptor (usbcore)
+ * @dev: the device whose device descriptor is being updated
+ * @size: how much of the descriptor to read
  *
  * Context: task context, might sleep.
  *
+ * Updates the copy of the device descriptor stored in the device structure,
+ * which dedicates space for this purpose.
+ *
  * Not exported, only for use by the core.  If drivers really want to read
  * the device descriptor directly, they can call usb_get_descriptor() with
  * type = USB_DT_DEVICE and index = 0.
  *
- * Returns: a pointer to a dynamically allocated usb_device_descriptor
- * structure (which the caller must deallocate), or an ERR_PTR value.
+ * This call is synchronous, and may not be used in an interrupt context.
+ *
+ * Return: The number of bytes received on success, or else the status code
+ * returned by the underlying usb_control_msg() call.
  */
-struct usb_device_descriptor *usb_get_device_descriptor(struct usb_device *udev)
+int usb_get_device_descriptor(struct usb_device *dev, unsigned int size)
 {
 	struct usb_device_descriptor *desc;
 	int ret;
 
+	if (size > sizeof(*desc))
+		return -EINVAL;
 	desc = kmalloc(sizeof(*desc), GFP_NOIO);
 	if (!desc)
-		return ERR_PTR(-ENOMEM);
-
-	ret = usb_get_descriptor(udev, USB_DT_DEVICE, 0, desc, sizeof(*desc));
-	if (ret == sizeof(*desc))
-		return desc;
+		return -ENOMEM;
 
+	ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size);
 	if (ret >= 0)
-		ret = -EMSGSIZE;
+		memcpy(&dev->descriptor, desc, size);
 	kfree(desc);
-	return ERR_PTR(ret);
+	return ret;
 }
 
 /*