It's only used with rings that have link trbs
Signed-off-by: Mathias Nyman <mathias.ny...@linux.intel.com>
---
drivers/usb/host/xhci-ring.c | 65 +++++++++++++++++---------------------------
1 file changed, 25 insertions(+), 40 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 2d8dcb1f..26ed512 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;
@@ -2867,36 +2859,29 @@ 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;
}
--
1.9.1
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