Merge remote-tracking branch 'stable/linux-4.19.y' into rpi-4.19.y

[platform/kernel/linux-rpi.git] / drivers / usb / host / xhci-ring.c

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 98b6760..bcf41da 100644 (file)
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -520,7 +520,10 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
        struct xhci_virt_ep *ep = &dev->eps[ep_index];
        struct xhci_ring *ep_ring;
        struct xhci_segment *new_seg;
+       struct xhci_segment *halted_seg = NULL;
        union xhci_trb *new_deq;
+       union xhci_trb *halted_trb;
+       int index = 0;
        dma_addr_t addr;
        u64 hw_dequeue;
        bool cycle_found = false;
@@ -541,7 +544,28 @@ void xhci_find_new_dequeue_state(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;
-       state->new_cycle_state = 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, cur_td->start_seg,
+                                      cur_td->first_trb, cur_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];
+               state->new_cycle_state = halted_trb->generic.field[3] & 0x1;
+               xhci_dbg(xhci, "Endpoint DCS = %d TRB index = %d cycle = %d\n",
+                        (u8)(hw_dequeue & 0x1), index,
+                        state->new_cycle_state);
+       } else {
+               state->new_cycle_state = hw_dequeue & 0x1;
+       }
        state->stream_id = stream_id;
 
        /*