diff options
Diffstat (limited to 'drivers/usb/host/xhci-ring.c')
-rw-r--r-- | drivers/usb/host/xhci-ring.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index e676749f543b..7dbd26a9bc24 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -559,8 +559,11 @@ static int xhci_move_dequeue_past_td(struct xhci_hcd *xhci, struct xhci_ring *ep_ring; struct xhci_command *cmd; struct xhci_segment *new_seg; + struct xhci_segment *halted_seg = NULL; union xhci_trb *new_deq; int new_cycle; + union xhci_trb *halted_trb; + int index = 0; dma_addr_t addr; u64 hw_dequeue; bool cycle_found = false; @@ -598,7 +601,27 @@ static int xhci_move_dequeue_past_td(struct xhci_hcd *xhci, hw_dequeue = xhci_get_hw_deq(xhci, dev, ep_index, stream_id); new_seg = ep_ring->deq_seg; new_deq = ep_ring->dequeue; - new_cycle = hw_dequeue & 0x1; + + /* + * Quirk: xHC write-back of the DCS field in the hardware dequeue + * pointer is wrong - use the cycle state of the TRB pointed to by + * the dequeue pointer. + */ + if (xhci->quirks & XHCI_EP_CTX_BROKEN_DCS && + !(ep->ep_state & EP_HAS_STREAMS)) + halted_seg = trb_in_td(xhci, td->start_seg, + td->first_trb, td->last_trb, + hw_dequeue & ~0xf, false); + if (halted_seg) { + index = ((dma_addr_t)(hw_dequeue & ~0xf) - halted_seg->dma) / + sizeof(*halted_trb); + halted_trb = &halted_seg->trbs[index]; + new_cycle = halted_trb->generic.field[3] & 0x1; + xhci_dbg(xhci, "Endpoint DCS = %d TRB index = %d cycle = %d\n", + (u8)(hw_dequeue & 0x1), index, new_cycle); + } else { + new_cycle = hw_dequeue & 0x1; + } /* * We want to find the pointer, segment and cycle state of the new trb |