diff --git a/drivers/usb/gadget/function/f_mtp.c b/drivers/usb/gadget/function/f_mtp.c
index 87ec420df0a6..b25cb3594d01 100644
--- a/drivers/usb/gadget/function/f_mtp.c
+++ b/drivers/usb/gadget/function/f_mtp.c
@@ -541,14 +541,10 @@ static ssize_t mtp_read(struct file *fp, char __user *buf,
 	ssize_t r = count;
 	unsigned xfer;
 	int ret = 0;
-	size_t len;
+	size_t len = 0;
 
 	DBG(cdev, "mtp_read(%zu)\n", count);
 
-	len = usb_ep_align_maybe(cdev->gadget, dev->ep_out, count);
-	if (len > MTP_BULK_BUFFER_SIZE)
-		return -EINVAL;
-
 	/* we will block until we're online */
 	DBG(cdev, "mtp_read: waiting for online state\n");
 	ret = wait_event_interruptible(dev->read_wq,
@@ -558,6 +554,14 @@ static ssize_t mtp_read(struct file *fp, char __user *buf,
 		goto done;
 	}
 	spin_lock_irq(&dev->lock);
+	if (dev->ep_out->desc) {
+		len = usb_ep_align_maybe(cdev->gadget, dev->ep_out, count);
+		if (len > MTP_BULK_BUFFER_SIZE) {
+			spin_unlock_irq(&dev->lock);
+			return -EINVAL;
+		}
+	}
+
 	if (dev->state == STATE_CANCELED) {
 		/* report cancelation to userspace */
 		dev->state = STATE_READY;