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| author | Mathias Nyman <mathias.nyman@linux.intel.com> | 2018-09-20 19:13:37 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-28 16:04:45 +0300 |
| commit | f8f80be501aa2f10669585c3e328fad079d8cb3a (patch) | |
| tree | 6ac1f3f37e5bee6f359519d2ed1978c58a69cecc /drivers/usb/host/xhci-ring.c | |
| parent | c94d41e9dd1ba3f95ca958ff04adeb64e3d6a9be (diff) | |
| download | linux-f8f80be501aa2f10669585c3e328fad079d8cb3a.tar.xz | |
xhci: Use soft retry to recover faster from transaction errors
Use soft retry to recover from a USB Transaction Errors that are caused by
temporary error conditions. The USB device is not aware that the xHC
has halted the endpoint, and will be waiting for another retry
A Soft Retry perform additional retries and recover from an error which has
caused the xHC to halt an endpoint.
Soft retry has some limitations:
Soft Retry attempts shall not be performed on Isoch endpoints
Soft Retry attempts shall not be performed if the device is behind a TT in
a HS Hub
Software shall limit the number of unsuccessful Soft Retry attempts to
prevent an infinite loop.
For more details on Soft retry see xhci specs 4.6.8.1
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/xhci-ring.c')
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index f0a99aa0ac58..c41341ea8449 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1155,6 +1155,10 @@ static void xhci_handle_cmd_reset_ep(struct xhci_hcd *xhci, int slot_id, /* Clear our internal halted state */ xhci->devs[slot_id]->eps[ep_index].ep_state &= ~EP_HALTED; } + + /* if this was a soft reset, then restart */ + if ((le32_to_cpu(trb->generic.field[3])) & TRB_TSP) + ring_doorbell_for_active_rings(xhci, slot_id, ep_index); } static void xhci_handle_cmd_enable_slot(struct xhci_hcd *xhci, int slot_id, @@ -2132,10 +2136,16 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td, union xhci_trb *ep_trb, struct xhci_transfer_event *event, struct xhci_virt_ep *ep, int *status) { + struct xhci_slot_ctx *slot_ctx; struct xhci_ring *ep_ring; u32 trb_comp_code; u32 remaining, requested, ep_trb_len; + unsigned int slot_id; + int ep_index; + slot_id = TRB_TO_SLOT_ID(le32_to_cpu(event->flags)); + slot_ctx = xhci_get_slot_ctx(xhci, xhci->devs[slot_id]->out_ctx); + ep_index = TRB_TO_EP_ID(le32_to_cpu(event->flags)) - 1; ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer)); trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len)); remaining = EVENT_TRB_LEN(le32_to_cpu(event->transfer_len)); @@ -2144,6 +2154,7 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td, switch (trb_comp_code) { case COMP_SUCCESS: + ep_ring->err_count = 0; /* handle success with untransferred data as short packet */ if (ep_trb != td->last_trb || remaining) { xhci_warn(xhci, "WARN Successful completion on short TX\n"); @@ -2167,6 +2178,14 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td, ep_trb_len = 0; remaining = 0; break; + case COMP_USB_TRANSACTION_ERROR: + if ((ep_ring->err_count++ > MAX_SOFT_RETRY) || + le32_to_cpu(slot_ctx->tt_info) & TT_SLOT) + break; + *status = 0; + xhci_cleanup_halted_endpoint(xhci, slot_id, ep_index, + ep_ring->stream_id, td, EP_SOFT_RESET); + return 0; default: /* do nothing */ break; |