From ae1e3f07320884ff25354d8233dc18d5283b0bb8 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Mon, 23 Jan 2017 14:20:15 +0200 Subject: [PATCH] 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 Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 8b78eee86262..bd00ada6643b 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -129,6 +129,21 @@ static void inc_td_cnt(struct urb *urb) 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 @@ static void td_to_noop(struct xhci_hcd *xhci, struct xhci_ring *ep_ring, 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);