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'
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Chen <peter.chen@xxxxxxx>
---
drivers/usb/host/xhci-mem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 032a702..580c890 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1718,7 +1718,7 @@ static int scratchpad_alloc(struct xhci_hcd *xhci, gfp_t flags)
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;
--
2.7.4