The xhci driver was causing intermittent 5 second delays from the USB keyboard polling hook. Executing something like a "sleep 1" for example would sleep for 5 seconds, unless an event occurred on the USB bus to shorten the delay.
Modeled after the code in the DWC2 driver, a nonblock state was added to quickly return instead of blocking for up to 5 seconds waiting for an event before timing out.
Signed-off-by: Jason Wessel jason.wessel@windriver.com --- drivers/usb/host/xhci-ring.c | 26 +++++++++++++++++--------- drivers/usb/host/xhci.c | 11 ++++++----- include/usb/xhci.h | 5 +++-- 3 files changed, 26 insertions(+), 16 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 86aeaab412..b7b2e16410 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -432,9 +432,11 @@ static int event_ready(struct xhci_ctrl *ctrl) * * @param ctrl Host controller data structure * @param expected TRB type expected from Event TRB + * @param nonblock when true do not block waiting for response * @return pointer to event trb */ -union xhci_trb *xhci_wait_for_event(struct xhci_ctrl *ctrl, trb_type expected) +union xhci_trb *xhci_wait_for_event(struct xhci_ctrl *ctrl, trb_type expected, + bool nonblock) { trb_type type; unsigned long ts = get_timer(0); @@ -442,8 +444,11 @@ union xhci_trb *xhci_wait_for_event(struct xhci_ctrl *ctrl, trb_type expected) do { union xhci_trb *event = ctrl->event_ring->dequeue;
- if (!event_ready(ctrl)) + if (!event_ready(ctrl)) { + if (nonblock) + return NULL; continue; + }
type = TRB_FIELD_TO_TYPE(le32_to_cpu(event->event_cmd.flags)); if (type == expected) @@ -493,7 +498,7 @@ static void abort_td(struct usb_device *udev, int ep_index)
xhci_queue_command(ctrl, NULL, udev->slot_id, ep_index, TRB_STOP_RING);
- event = xhci_wait_for_event(ctrl, TRB_TRANSFER); + event = xhci_wait_for_event(ctrl, TRB_TRANSFER, false); field = le32_to_cpu(event->trans_event.flags); BUG_ON(TRB_TO_SLOT_ID(field) != udev->slot_id); BUG_ON(TRB_TO_EP_INDEX(field) != ep_index); @@ -501,7 +506,7 @@ static void abort_td(struct usb_device *udev, int ep_index) != COMP_STOP))); xhci_acknowledge_event(ctrl);
- event = xhci_wait_for_event(ctrl, TRB_COMPLETION); + event = xhci_wait_for_event(ctrl, TRB_COMPLETION, false); BUG_ON(TRB_TO_SLOT_ID(le32_to_cpu(event->event_cmd.flags)) != udev->slot_id || GET_COMP_CODE(le32_to_cpu( event->event_cmd.status)) != COMP_SUCCESS); @@ -509,7 +514,7 @@ static void abort_td(struct usb_device *udev, int ep_index)
xhci_queue_command(ctrl, (void *)((uintptr_t)ring->enqueue | ring->cycle_state), udev->slot_id, ep_index, TRB_SET_DEQ); - event = xhci_wait_for_event(ctrl, TRB_COMPLETION); + event = xhci_wait_for_event(ctrl, TRB_COMPLETION, false); BUG_ON(TRB_TO_SLOT_ID(le32_to_cpu(event->event_cmd.flags)) != udev->slot_id || GET_COMP_CODE(le32_to_cpu( event->event_cmd.status)) != COMP_SUCCESS); @@ -552,10 +557,11 @@ static void record_transfer_result(struct usb_device *udev, * @param pipe contains the DIR_IN or OUT , devnum * @param length length of the buffer * @param buffer buffer to be read/written based on the request + * @param nonblock when true do not block waiting for response * @return returns 0 if successful else -1 on failure */ int xhci_bulk_tx(struct usb_device *udev, unsigned long pipe, - int length, void *buffer) + int length, void *buffer, bool nonblock) { int num_trbs = 0; struct xhci_generic_trb *start_trb; @@ -714,8 +720,10 @@ int xhci_bulk_tx(struct usb_device *udev, unsigned long pipe,
giveback_first_trb(udev, ep_index, start_cycle, start_trb);
- event = xhci_wait_for_event(ctrl, TRB_TRANSFER); + event = xhci_wait_for_event(ctrl, TRB_TRANSFER, nonblock); if (!event) { + if (nonblock) + return -EINVAL; debug("XHCI bulk transfer timed out, aborting...\n"); abort_td(udev, ep_index); udev->status = USB_ST_NAK_REC; /* closest thing to a timeout */ @@ -911,7 +919,7 @@ int xhci_ctrl_tx(struct usb_device *udev, unsigned long pipe,
giveback_first_trb(udev, ep_index, start_cycle, start_trb);
- event = xhci_wait_for_event(ctrl, TRB_TRANSFER); + event = xhci_wait_for_event(ctrl, TRB_TRANSFER, false); if (!event) goto abort; field = le32_to_cpu(event->trans_event.flags); @@ -929,7 +937,7 @@ int xhci_ctrl_tx(struct usb_device *udev, unsigned long pipe, if (GET_COMP_CODE(le32_to_cpu(event->trans_event.transfer_len)) == COMP_SHORT_TX) { /* Short data stage, clear up additional status stage event */ - event = xhci_wait_for_event(ctrl, TRB_TRANSFER); + event = xhci_wait_for_event(ctrl, TRB_TRANSFER, false); if (!event) goto abort; BUG_ON(TRB_TO_SLOT_ID(field) != slot_id); diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index f635bb39f6..57d799e4cb 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -495,7 +495,7 @@ static int xhci_configure_endpoints(struct usb_device *udev, bool ctx_change) xhci_flush_cache((uintptr_t)in_ctx->bytes, in_ctx->size); xhci_queue_command(ctrl, in_ctx->bytes, udev->slot_id, 0, ctx_change ? TRB_EVAL_CONTEXT : TRB_CONFIG_EP); - event = xhci_wait_for_event(ctrl, TRB_COMPLETION); + event = xhci_wait_for_event(ctrl, TRB_COMPLETION, false); BUG_ON(TRB_TO_SLOT_ID(le32_to_cpu(event->event_cmd.flags)) != udev->slot_id);
@@ -691,7 +691,7 @@ static int xhci_address_device(struct usb_device *udev, int root_portnr) ctrl_ctx->drop_flags = 0;
xhci_queue_command(ctrl, (void *)ctrl_ctx, slot_id, 0, TRB_ADDR_DEV); - event = xhci_wait_for_event(ctrl, TRB_COMPLETION); + event = xhci_wait_for_event(ctrl, TRB_COMPLETION, false); BUG_ON(TRB_TO_SLOT_ID(le32_to_cpu(event->event_cmd.flags)) != slot_id);
switch (GET_COMP_CODE(le32_to_cpu(event->event_cmd.status))) { @@ -766,7 +766,7 @@ static int _xhci_alloc_device(struct usb_device *udev) }
xhci_queue_command(ctrl, NULL, 0, 0, TRB_ENABLE_SLOT); - event = xhci_wait_for_event(ctrl, TRB_COMPLETION); + event = xhci_wait_for_event(ctrl, TRB_COMPLETION, false); BUG_ON(GET_COMP_CODE(le32_to_cpu(event->event_cmd.status)) != COMP_SUCCESS);
@@ -1152,6 +1152,7 @@ unknown: * @param buffer buffer to be read/written based on the request * @param length length of the buffer * @param interval interval of the interrupt + * @param nonblock when true do not block waiting for response * @return 0 */ static int _xhci_submit_int_msg(struct usb_device *udev, unsigned long pipe, @@ -1169,7 +1170,7 @@ static int _xhci_submit_int_msg(struct usb_device *udev, unsigned long pipe, * (at most) one TD. A TD (comprised of sg list entries) can * take several service intervals to transmit. */ - return xhci_bulk_tx(udev, pipe, length, buffer); + return xhci_bulk_tx(udev, pipe, length, buffer, nonblock); }
/** @@ -1189,7 +1190,7 @@ static int _xhci_submit_bulk_msg(struct usb_device *udev, unsigned long pipe, return -EINVAL; }
- return xhci_bulk_tx(udev, pipe, length, buffer); + return xhci_bulk_tx(udev, pipe, length, buffer, false); }
/** diff --git a/include/usb/xhci.h b/include/usb/xhci.h index 7d34103fd5..73db77fc02 100644 --- a/include/usb/xhci.h +++ b/include/usb/xhci.h @@ -1249,9 +1249,10 @@ void xhci_setup_addressable_virt_dev(struct xhci_ctrl *ctrl, void xhci_queue_command(struct xhci_ctrl *ctrl, u8 *ptr, u32 slot_id, u32 ep_index, trb_type cmd); void xhci_acknowledge_event(struct xhci_ctrl *ctrl); -union xhci_trb *xhci_wait_for_event(struct xhci_ctrl *ctrl, trb_type expected); +union xhci_trb *xhci_wait_for_event(struct xhci_ctrl *ctrl, trb_type expected, + bool nonblock); int xhci_bulk_tx(struct usb_device *udev, unsigned long pipe, - int length, void *buffer); + int length, void *buffer, bool nonblock); int xhci_ctrl_tx(struct usb_device *udev, unsigned long pipe, struct devrequest *req, int length, void *buffer); int xhci_check_maxpacket(struct usb_device *udev);