xhci: Introduce helper to turn one TRB into a no-op
Useful for turning both transfer and command trbs
into no-ops.
Based on earlier code by Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 8b78eee..bd00ada 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -129,6 +129,21 @@
urb_priv->td_cnt++;
}
+static void trb_to_noop(union xhci_trb *trb, u32 noop_type)
+{
+ if (trb_is_link(trb)) {
+ /* unchain chained link TRBs */
+ trb->link.control &= cpu_to_le32(~TRB_CHAIN);
+ } else {
+ trb->generic.field[0] = 0;
+ trb->generic.field[1] = 0;
+ trb->generic.field[2] = 0;
+ /* Preserve only the cycle bit of this TRB */
+ trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
+ trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(noop_type));
+ }
+}
+
/* Updates trb to point to the next TRB in the ring, and updates seg if the next
* TRB is in a new segment. This does not skip over link TRBs, and it does not
* effect the ring dequeue or enqueue pointers.
@@ -592,18 +607,8 @@
union xhci_trb *trb = td->first_trb;
while (1) {
- if (trb_is_link(trb)) {
- /* unchain chained link TRBs */
- trb->link.control &= cpu_to_le32(~TRB_CHAIN);
- } else {
- trb->generic.field[0] = 0;
- trb->generic.field[1] = 0;
- trb->generic.field[2] = 0;
- /* Preserve only the cycle bit of this TRB */
- trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
- trb->generic.field[3] |= cpu_to_le32(
- TRB_TYPE(TRB_TR_NOOP));
- }
+ trb_to_noop(trb, TRB_TR_NOOP);
+
/* flip cycle if asked to */
if (flip_cycle && trb != td->first_trb && trb != td->last_trb)
trb->generic.field[3] ^= cpu_to_le32(TRB_CYCLE);