From 28a2369f7d72ece55089f33e7d7b9c1223673cc3 Mon Sep 17 00:00:00 2001 From: Shyam Sundar S K Date: Thu, 20 Jul 2017 14:48:28 +0300 Subject: usb: xhci: Issue stop EP command only when the EP state is running on AMD platforms with SNPS 3.1 USB controller if stop endpoint command is issued the controller does not respond, when the EP is not in running state. HW completes the command execution and reports "Context State Error" completion code. This is as per the spec. However HW on receiving the second command additionally marks EP to Flow control state in HW which is RTL bug. This bug causes the HW not to respond to any further doorbells that are rung by the driver. This makes the EP to not functional anymore and causes gross functional failures. As a workaround, not to hit this problem, it's better to check the EP state and issue a stop EP command only when the EP is in running state. As a sidenote, even with this patch there is still a possibility of triggering the RTL bug if the context state races with the stop endpoint command as described in xHCI spec 4.6.9 [code simplification and reworded sidenote in commit message -Mathias] Signed-off-by: Shyam Sundar S K Signed-off-by: Nehal Shah Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'drivers/usb/host/xhci-hub.c') diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 1adae9eab831..364f60275043 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -398,14 +398,21 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend) spin_lock_irqsave(&xhci->lock, flags); for (i = LAST_EP_INDEX; i > 0; i--) { if (virt_dev->eps[i].ring && virt_dev->eps[i].ring->dequeue) { + struct xhci_ep_ctx *ep_ctx; struct xhci_command *command; + + ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->out_ctx, i); + + /* Check ep is running, required by AMD SNPS 3.1 xHC */ + if (GET_EP_CTX_STATE(ep_ctx) != EP_STATE_RUNNING) + continue; + command = xhci_alloc_command(xhci, false, false, GFP_NOWAIT); if (!command) { spin_unlock_irqrestore(&xhci->lock, flags); xhci_free_command(xhci, cmd); return -ENOMEM; - } xhci_queue_stop_endpoint(xhci, command, slot_id, i, suspend); -- cgit v1.2.3 From a54408d0a004757789863d74e29c2297edae0b4d Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Thu, 20 Jul 2017 14:48:29 +0300 Subject: xhci: fix 20000ms port resume timeout A uncleared PLC (port link change) bit will prevent furuther port event interrupts for that port. Leaving it uncleared caused get_port_status() to timeout after 20000ms while waiting to get the final port event interrupt for resume -> U0 state change. This is a targeted fix for a specific case where we get a port resume event racing with xhci resume. The port event interrupt handler notices xHC is not yet running and bails out early, leaving PLC uncleared. The whole xhci port resuming needs more attention, but while working on it it anyways makes sense to always ensure PLC is cleared in get_port_status before setting a new link state and waiting for its completion. Cc: Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/usb/host/xhci-hub.c') diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 364f60275043..9ef5f68e3213 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -904,6 +904,9 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd, clear_bit(wIndex, &bus_state->resuming_ports); set_bit(wIndex, &bus_state->rexit_ports); + + xhci_test_and_clear_bit(xhci, port_array, wIndex, + PORT_PLC); xhci_set_link_state(xhci, port_array, wIndex, XDEV_U0); -- cgit v1.2.3 From 576d55460e7f209139545a348746c2fcadf61bc3 Mon Sep 17 00:00:00 2001 From: Peter Chen Date: Thu, 20 Jul 2017 14:48:30 +0300 Subject: usb: xhci: fix spinlock recursion for USB2 test mode Both xhci_hub_control and xhci_disable_slot tries to hold spinlock, the spinlock recursion occurs when enters USB2 test mode. Fix it by unlock spinlock before calling xhci_disable_slot. Cc: Fixes: 0f1d832ed1fb ("usb: xhci: Add port test modes support for usb2") Signed-off-by: Peter Chen Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-hub.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/usb/host/xhci-hub.c') diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 9ef5f68e3213..00721e8807ab 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -610,12 +610,14 @@ static int xhci_enter_test_mode(struct xhci_hcd *xhci, /* Disable all Device Slots */ xhci_dbg(xhci, "Disable all slots\n"); + spin_unlock_irqrestore(&xhci->lock, *flags); for (i = 1; i <= HCS_MAX_SLOTS(xhci->hcs_params1); i++) { retval = xhci_disable_slot(xhci, NULL, i); if (retval) xhci_err(xhci, "Failed to disable slot %d, %d. Enter test mode anyway\n", i, retval); } + spin_lock_irqsave(&xhci->lock, *flags); /* Put all ports to the Disable state by clear PP */ xhci_dbg(xhci, "Disable all port (PP = 0)\n"); /* Power off USB3 ports*/ -- cgit v1.2.3