commit d72348fb5ca634583bf3f79996cc4b3ef91d9c3a
author Johan Hovold <johan@kernel.org> Thu Apr 23 16:06:50 2015 +0200
committer Felipe Balbi <balbi@ti.com> Mon Apr 27 15:48:39 2015 -0500
tree d24d6d333f8ad87342a929f137fdff6d7a6ea92e
parent 2d9c7f3ca54625f4d740af78f84ee232da3ca937

usb: musb: fix inefficient copy of unaligned buffers

Make sure only to copy any actual data rather than the whole buffer,
when releasing the temporary buffer used for unaligned non-isochronous
transfers.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/musb/musb_host.c

diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index c3d5fc9..e1fb5d8 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -2512,6 +2512,7 @@
 {
 	enum dma_data_direction dir;
 	struct musb_temp_buffer *temp;
+	size_t length;
 
 	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
 		return;
@@ -2522,8 +2523,12 @@
 			    data);
 
 	if (dir == DMA_FROM_DEVICE) {
-		memcpy(temp->old_xfer_buffer, temp->data,
-		       urb->transfer_buffer_length);
+		if (usb_pipeisoc(urb->pipe))
+			length = urb->transfer_buffer_length;
+		else
+			length = urb->actual_length;
+
+		memcpy(temp->old_xfer_buffer, temp->data, length);
 	}
 	urb->transfer_buffer = temp->old_xfer_buffer;
 	kfree(temp->kmalloc_ptr);