diff options
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 65 |
1 files changed, 25 insertions, 40 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 64e24d2d19f0..21e1dd62ebf8 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -89,19 +89,6 @@ dma_addr_t xhci_trb_virt_to_dma(struct xhci_segment *seg, return seg->dma + (segment_offset * sizeof(*trb)); } -/* Does this link TRB point to the first segment in a ring, - * or was the previous TRB the last TRB on the last segment in the ERST? - */ -static bool last_trb_on_last_seg(struct xhci_hcd *xhci, struct xhci_ring *ring, - struct xhci_segment *seg, union xhci_trb *trb) -{ - if (ring == xhci->event_ring) - return (trb == &seg->trbs[TRBS_PER_SEGMENT]) && - (seg->next == xhci->event_ring->first_seg); - else - return le32_to_cpu(trb->link.control) & LINK_TOGGLE; -} - static bool trb_is_link(union xhci_trb *trb) { return TRB_TYPE_LINK_LE32(trb->link.control); @@ -118,6 +105,11 @@ static bool last_trb_on_ring(struct xhci_ring *ring, return last_trb_on_seg(seg, trb) && (seg->next == ring->first_seg); } +static bool link_trb_toggles_cycle(union xhci_trb *trb) +{ + return le32_to_cpu(trb->link.control) & LINK_TOGGLE; +} + /* 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. @@ -226,7 +218,7 @@ static void inc_enq(struct xhci_hcd *xhci, struct xhci_ring *ring, next->link.control ^= cpu_to_le32(TRB_CYCLE); /* Toggle the cycle bit after the last ring segment. */ - if (last_trb_on_last_seg(xhci, ring, ring->enq_seg, next)) + if (link_trb_toggles_cycle(next)) ring->cycle_state ^= 1; ring->enq_seg = ring->enq_seg->next; @@ -2885,36 +2877,29 @@ static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring, } } - if (trb_is_link(ep_ring->enqueue)) { - struct xhci_ring *ring = ep_ring; - union xhci_trb *next; - - next = ring->enqueue; + while (trb_is_link(ep_ring->enqueue)) { + /* If we're not dealing with 0.95 hardware or isoc rings + * on AMD 0.96 host, clear the chain bit. + */ + if (!xhci_link_trb_quirk(xhci) && + !(ep_ring->type == TYPE_ISOC && + (xhci->quirks & XHCI_AMD_0x96_HOST))) + ep_ring->enqueue->link.control &= + cpu_to_le32(~TRB_CHAIN); + else + ep_ring->enqueue->link.control |= + cpu_to_le32(TRB_CHAIN); - while (trb_is_link(next)) { - /* If we're not dealing with 0.95 hardware or isoc rings - * on AMD 0.96 host, clear the chain bit. - */ - if (!xhci_link_trb_quirk(xhci) && - !(ring->type == TYPE_ISOC && - (xhci->quirks & XHCI_AMD_0x96_HOST))) - next->link.control &= cpu_to_le32(~TRB_CHAIN); - else - next->link.control |= cpu_to_le32(TRB_CHAIN); + wmb(); + ep_ring->enqueue->link.control ^= cpu_to_le32(TRB_CYCLE); - wmb(); - next->link.control ^= cpu_to_le32(TRB_CYCLE); + /* Toggle the cycle bit after the last ring segment. */ + if (link_trb_toggles_cycle(ep_ring->enqueue)) + ep_ring->cycle_state ^= 1; - /* Toggle the cycle bit after the last ring segment. */ - if (last_trb_on_last_seg(xhci, ring, ring->enq_seg, next)) { - ring->cycle_state ^= 1; - } - ring->enq_seg = ring->enq_seg->next; - ring->enqueue = ring->enq_seg->trbs; - next = ring->enqueue; - } + ep_ring->enq_seg = ep_ring->enq_seg->next; + ep_ring->enqueue = ep_ring->enq_seg->trbs; } - return 0; } |