From ef513be0a9057cc6baf5d29566aaaefa214ba344 Mon Sep 17 00:00:00 2001 From: Jim Lin Date: Mon, 3 Jun 2019 18:53:44 +0800 Subject: [PATCH] usb: xhci: Add Clear_TT_Buffer USB 2.0 specification chapter 11.17.5 says "as part of endpoint halt processing for full-/low-speed endpoints connected via a TT, the host software must use the Clear_TT_Buffer request to the TT to ensure that the buffer is not in the busy state". In our case, a full-speed speaker (ConferenceCam) is behind a high- speed hub (ConferenceCam Connect), sometimes once we get STALL on a request we may continue to get STALL with the folllowing requests, like Set_Interface. Here we invoke usb_hub_clear_tt_buffer() to send Clear_TT_Buffer request to the hub of the device for the following Set_Interface requests to the device to get ACK successfully. Signed-off-by: Jim Lin Acked-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 27 ++++++++++++++++++++++++++- drivers/usb/host/xhci.c | 21 +++++++++++++++++++++ drivers/usb/host/xhci.h | 5 +++++ 3 files changed, 52 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index feffceb31e8a..a52fd96e70e9 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -399,7 +399,7 @@ void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, * stream once the endpoint is on the HW schedule. */ if ((ep_state & EP_STOP_CMD_PENDING) || (ep_state & SET_DEQ_PENDING) || - (ep_state & EP_HALTED)) + (ep_state & EP_HALTED) || (ep_state & EP_CLEARING_TT)) return; writel(DB_VALUE(ep_index, stream_id), db_addr); /* The CPU has better things to do at this point than wait for a @@ -433,6 +433,13 @@ static void ring_doorbell_for_active_rings(struct xhci_hcd *xhci, } } +void xhci_ring_doorbell_for_active_rings(struct xhci_hcd *xhci, + unsigned int slot_id, + unsigned int ep_index) +{ + ring_doorbell_for_active_rings(xhci, slot_id, ep_index); +} + /* Get the right ring for the given slot_id, ep_index and stream_id. * If the endpoint supports streams, boundary check the URB's stream ID. * If the endpoint doesn't support streams, return the singular endpoint ring. @@ -1794,6 +1801,23 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci, return NULL; } +static void xhci_clear_hub_tt_buffer(struct xhci_hcd *xhci, struct xhci_td *td, + struct xhci_virt_ep *ep) +{ + /* + * As part of low/full-speed endpoint-halt processing + * we must clear the TT buffer (USB 2.0 specification 11.17.5). + */ + if (td->urb->dev->tt && !usb_pipeint(td->urb->pipe) && + (td->urb->dev->tt->hub != xhci_to_hcd(xhci)->self.root_hub) && + !(ep->ep_state & EP_CLEARING_TT)) { + ep->ep_state |= EP_CLEARING_TT; + td->urb->ep->hcpriv = td->urb->dev; + if (usb_hub_clear_tt_buffer(td->urb)) + ep->ep_state &= ~EP_CLEARING_TT; + } +} + static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci, unsigned int slot_id, unsigned int ep_index, unsigned int stream_id, struct xhci_td *td, @@ -1812,6 +1836,7 @@ static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci, if (reset_type == EP_HARD_RESET) { ep->ep_state |= EP_HARD_CLEAR_TOGGLE; xhci_cleanup_stalled_ring(xhci, ep_index, stream_id, td); + xhci_clear_hub_tt_buffer(xhci, td, ep); } xhci_ring_cmd_db(xhci); } diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 4f92643e3a4c..ef5702a45067 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -5163,6 +5163,26 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks) } EXPORT_SYMBOL_GPL(xhci_gen_setup); +static void xhci_clear_tt_buffer_complete(struct usb_hcd *hcd, + struct usb_host_endpoint *ep) +{ + struct xhci_hcd *xhci; + struct usb_device *udev; + unsigned int slot_id; + unsigned int ep_index; + unsigned long flags; + + xhci = hcd_to_xhci(hcd); + udev = (struct usb_device *)ep->hcpriv; + slot_id = udev->slot_id; + ep_index = xhci_get_endpoint_index(&ep->desc); + + spin_lock_irqsave(&xhci->lock, flags); + xhci->devs[slot_id]->eps[ep_index].ep_state &= ~EP_CLEARING_TT; + xhci_ring_doorbell_for_active_rings(xhci, slot_id, ep_index); + spin_unlock_irqrestore(&xhci->lock, flags); +} + static const struct hc_driver xhci_hc_driver = { .description = "xhci-hcd", .product_desc = "xHCI Host Controller", @@ -5224,6 +5244,7 @@ static const struct hc_driver xhci_hc_driver = { .enable_usb3_lpm_timeout = xhci_enable_usb3_lpm_timeout, .disable_usb3_lpm_timeout = xhci_disable_usb3_lpm_timeout, .find_raw_port_number = xhci_find_raw_port_number, + .clear_tt_buffer_complete = xhci_clear_tt_buffer_complete, }; void xhci_init_driver(struct hc_driver *drv, diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 7f8b950d1a73..34789f4db555 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -936,6 +936,8 @@ struct xhci_virt_ep { #define EP_GETTING_NO_STREAMS (1 << 5) #define EP_HARD_CLEAR_TOGGLE (1 << 6) #define EP_SOFT_CLEAR_TOGGLE (1 << 7) +/* usb_hub_clear_tt_buffer is in progress */ +#define EP_CLEARING_TT (1 << 8) /* ---- Related to URB cancellation ---- */ struct list_head cancelled_td_list; /* Watchdog timer for stop endpoint command to cancel URBs */ @@ -2102,6 +2104,9 @@ void xhci_handle_command_timeout(struct work_struct *work); void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, unsigned int slot_id, unsigned int ep_index, unsigned int stream_id); +void xhci_ring_doorbell_for_active_rings(struct xhci_hcd *xhci, + unsigned int slot_id, + unsigned int ep_index); void xhci_cleanup_command_queue(struct xhci_hcd *xhci); void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring); unsigned int count_trbs(u64 addr, u64 len); -- 2.11.0