[PATCH 1/4] xhci: Fix incorrect stream context type macro

[Mathias Nyman <mathias.nyman@linux.intel.com>]

The stream contex type (SCT) bitfield is used both in the stream context
data structure,  and in the 'Set TR Dequeue pointer' command TRB.
In both cases it uses bits 3:1

The SCT_FOR_TRB(p) macro used to set the stream context type (SCT) field
for the 'Set TR Dequeue pointer' command TRB incorrectly shifts the value
1 bit left before masking the three bits.

Fix this by first masking and rshifting, just like the similar
SCT_FOR_CTX(p) macro does

This issue has not been visibile as the lost bit 3 is only used with
secondary stream arrays (SSA). Xhci driver currently only supports using
a primary stream array with Linear stream addressing.

Fixes: 95241dbdf828 ("xhci: Set SCT field for Set TR dequeue on streams")
Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
---
 drivers/usb/host/xhci.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 620502de971a..f0fb696d5619 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1001,7 +1001,7 @@ enum xhci_setup_dev {
 /* Set TR Dequeue Pointer command TRB fields, 6.4.3.9 */
 #define TRB_TO_STREAM_ID(p)		((((p) & (0xffff << 16)) >> 16))
 #define STREAM_ID_FOR_TRB(p)		((((p)) & 0xffff) << 16)
-#define SCT_FOR_TRB(p)			(((p) << 1) & 0x7)
+#define SCT_FOR_TRB(p)			(((p) & 0x7) << 1)
 
 /* Link TRB specific fields */
 #define TRB_TC			(1<<1)
-- 
2.25.1