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path: root/drivers/usb/host/xhci-ring.c
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Diffstat (limited to 'drivers/usb/host/xhci-ring.c')
-rw-r--r--drivers/usb/host/xhci-ring.c39
1 files changed, 34 insertions, 5 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index e676749f543b..311597bba80e 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -366,16 +366,22 @@ static void xhci_handle_stopped_cmd_ring(struct xhci_hcd *xhci,
/* Must be called with xhci->lock held, releases and aquires lock back */
static int xhci_abort_cmd_ring(struct xhci_hcd *xhci, unsigned long flags)
{
- u64 temp_64;
+ u32 temp_32;
int ret;
xhci_dbg(xhci, "Abort command ring\n");
reinit_completion(&xhci->cmd_ring_stop_completion);
- temp_64 = xhci_read_64(xhci, &xhci->op_regs->cmd_ring);
- xhci_write_64(xhci, temp_64 | CMD_RING_ABORT,
- &xhci->op_regs->cmd_ring);
+ /*
+ * The control bits like command stop, abort are located in lower
+ * dword of the command ring control register. Limit the write
+ * to the lower dword to avoid corrupting the command ring pointer
+ * in case if the command ring is stopped by the time upper dword
+ * is written.
+ */
+ temp_32 = readl(&xhci->op_regs->cmd_ring);
+ writel(temp_32 | CMD_RING_ABORT, &xhci->op_regs->cmd_ring);
/* Section 4.6.1.2 of xHCI 1.0 spec says software should also time the
* completion of the Command Abort operation. If CRR is not negated in 5
@@ -559,8 +565,11 @@ 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 +607,27 @@ 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