[PATCH 3.18 21/59] usb: host: xhci-mem: allocate zeroed Scratchpad Buffer

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Peter Chen <peter.chen@xxxxxxx>

commit 7480d912d549f414e0ce39331870899e89a5598c upstream.

According to xHCI ch4.20 Scratchpad Buffers, the Scratchpad
Buffer needs to be zeroed.

	...
	The following operations take place to allocate
       	Scratchpad Buffers to the xHC:
	...
		b. Software clears the Scratchpad Buffer to '0'

Signed-off-by: Peter Chen <peter.chen@xxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/host/xhci-mem.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1676,7 +1676,7 @@ static int scratchpad_alloc(struct xhci_
 	xhci->dcbaa->dev_context_ptrs[0] = cpu_to_le64(xhci->scratchpad->sp_dma);
 	for (i = 0; i < num_sp; i++) {
 		dma_addr_t dma;
-		void *buf = dma_alloc_coherent(dev, xhci->page_size, &dma,
+		void *buf = dma_zalloc_coherent(dev, xhci->page_size, &dma,
 				flags);
 		if (!buf)
 			goto fail_sp5;