From 1c7439c61fa6516419c32a9824976334ea969d47 Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 14 Nov 2012 15:58:52 -0800 Subject: USB: Handle auto-transition from hot to warm reset. USB 3.0 hubs and roothubs will automatically transition a failed hot reset to a warm (BH) reset. In that case, the warm reset change bit will be set, and the link state change bit may also be set. Change hub_port_finish_reset to unconditionally clear those change bits for USB 3.0 hubs. If these bits are not cleared, we may lose port change events from the roothub. This commit should be backported to kernels as old as 3.2, that contain the commit 75d7cf72ab9fa01dc70877aa5c68e8ef477229dc "usbcore: refine warm reset logic". Signed-off-by: Sarah Sharp Acked-by: Alan Stern Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index a815fd2cc5e7..7f8f10ec127e 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2580,16 +2580,16 @@ static void hub_port_finish_reset(struct usb_hub *hub, int port1, clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_RESET); /* FIXME need disconnect() for NOTATTACHED device */ - if (warm) { + if (hub_is_superspeed(hub->hdev)) { clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_BH_PORT_RESET); clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_PORT_LINK_STATE); - } else { + } + if (!warm) usb_set_device_state(udev, *status ? USB_STATE_NOTATTACHED : USB_STATE_DEFAULT); - } break; } } -- cgit v1.2.3 From 8b8132bc3d1cc3d4c0687e4d638a482fa920d98a Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 14 Nov 2012 16:10:49 -0800 Subject: USB: Ignore xHCI Reset Device status. When the USB core finishes reseting a USB device, the xHCI driver sends a Reset Device command to the host. The xHC then updates its internal representation of the USB device to the 'Default' device state. If the device was already in the Default state, the xHC will complete the command with an error status. If a device needs to be reset several times during enumeration, the second reset will always fail because of the xHCI Reset Device command. This can cause issues during enumeration. For example, usb_reset_and_verify_device calls into hub_port_init in a loop. Say that on the first call into hub_port_init, the device is successfully reset, but doesn't respond to several set address control transfers. Then the port will be disabled, but the udev will remain in tact. usb_reset_and_verify_device will call into hub_port_init again. On the second call into hub_port_init, the device will be reset, and the xHCI driver will issue a Reset Device command. This command will fail (because the device is already in the Default state), and usb_reset_and_verify_device will fail. The port will be disabled, and the device won't be able to enumerate. Fix this by ignoring the return value of the HCD reset_device callback. This commit should be backported to kernels as old as 3.2, that contain the commit 75d7cf72ab9fa01dc70877aa5c68e8ef477229dc "usbcore: refine warm reset logic". Signed-off-by: Sarah Sharp Acked-by: Alan Stern Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 7f8f10ec127e..3bc50fc110eb 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2565,14 +2565,11 @@ static void hub_port_finish_reset(struct usb_hub *hub, int port1, msleep(10 + 40); update_devnum(udev, 0); hcd = bus_to_hcd(udev->bus); - if (hcd->driver->reset_device) { - *status = hcd->driver->reset_device(hcd, udev); - if (*status < 0) { - dev_err(&udev->dev, "Cannot reset " - "HCD device state\n"); - break; - } - } + /* The xHC may think the device is already reset, + * so ignore the status. + */ + if (hcd->driver->reset_device) + hcd->driver->reset_device(hcd, udev); } /* FALL THROUGH */ case -ENOTCONN: -- cgit v1.2.3 From 41e7e056cdc662f704fa9262e5c6e213b4ab45dd Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 14 Nov 2012 16:42:32 -0800 Subject: USB: Allow USB 3.0 ports to be disabled. If hot and warm reset fails, or a port remains in the Compliance Mode, the USB core needs to be able to disable a USB 3.0 port. Unlike USB 2.0 ports, once the port is placed into the Disabled link state, it will not report any new device connects. To get device connect notifications, we need to put the link into the Disabled state, and then the RxDetect state. The xHCI driver needs to atomically clear all change bits on USB 3.0 port disable, so that we get Port Status Change Events for future port changes. We could technically do this in the USB core instead of in the xHCI roothub code, since the port state machine can't advance out of the disabled state until we set the link state to RxDetect. However, external USB 3.0 hubs don't need this code. They are level-triggered, not edge-triggered like xHCI, so they will continue to send interrupt events when any change bit is set. Therefore it doesn't make sense to put this code in the USB core. This patch is part of a series to fix several reports of infinite loops on device enumeration failure. This includes John, when he boots with a USB 3.0 device (Roseweil eusb3 enclosure) attached to his NEC 0.96 host controller. The fix requires warm reset support, so it does not make sense to backport this patch to stable kernels without warm reset support. This patch should be backported to kernels as old as 3.2, contain the commit ID 75d7cf72ab9fa01dc70877aa5c68e8ef477229dc "usbcore: refine warm reset logic" Signed-off-by: Sarah Sharp Acked-by: Alan Stern Reported-by: John Covici Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 63 +++++++++++++++++++++++++++++++++++++++++++-- drivers/usb/host/xhci-hub.c | 31 ++++++++++++++++++++-- 2 files changed, 90 insertions(+), 4 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 3bc50fc110eb..968ec37a0f02 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -877,6 +877,60 @@ static int hub_hub_status(struct usb_hub *hub, return ret; } +static int hub_set_port_link_state(struct usb_hub *hub, int port1, + unsigned int link_status) +{ + return set_port_feature(hub->hdev, + port1 | (link_status << 3), + USB_PORT_FEAT_LINK_STATE); +} + +/* + * If USB 3.0 ports are placed into the Disabled state, they will no longer + * detect any device connects or disconnects. This is generally not what the + * USB core wants, since it expects a disabled port to produce a port status + * change event when a new device connects. + * + * Instead, set the link state to Disabled, wait for the link to settle into + * that state, clear any change bits, and then put the port into the RxDetect + * state. + */ +static int hub_usb3_port_disable(struct usb_hub *hub, int port1) +{ + int ret; + int total_time; + u16 portchange, portstatus; + + if (!hub_is_superspeed(hub->hdev)) + return -EINVAL; + + ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED); + if (ret) { + dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n", + port1, ret); + return ret; + } + + /* Wait for the link to enter the disabled state. */ + for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) { + ret = hub_port_status(hub, port1, &portstatus, &portchange); + if (ret < 0) + return ret; + + if ((portstatus & USB_PORT_STAT_LINK_STATE) == + USB_SS_PORT_LS_SS_DISABLED) + break; + if (total_time >= HUB_DEBOUNCE_TIMEOUT) + break; + msleep(HUB_DEBOUNCE_STEP); + } + if (total_time >= HUB_DEBOUNCE_TIMEOUT) + dev_warn(hub->intfdev, "Could not disable port %d after %d ms\n", + port1, total_time); + + return hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_RX_DETECT); +} + static int hub_port_disable(struct usb_hub *hub, int port1, int set_state) { struct usb_device *hdev = hub->hdev; @@ -885,8 +939,13 @@ static int hub_port_disable(struct usb_hub *hub, int port1, int set_state) if (hub->ports[port1 - 1]->child && set_state) usb_set_device_state(hub->ports[port1 - 1]->child, USB_STATE_NOTATTACHED); - if (!hub->error && !hub_is_superspeed(hub->hdev)) - ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE); + if (!hub->error) { + if (hub_is_superspeed(hub->hdev)) + ret = hub_usb3_port_disable(hub, port1); + else + ret = clear_port_feature(hdev, port1, + USB_PORT_FEAT_ENABLE); + } if (ret) dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n", port1, ret); diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index a686cf4905bb..a7dd4f311e14 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -761,12 +761,39 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, break; case USB_PORT_FEAT_LINK_STATE: temp = xhci_readl(xhci, port_array[wIndex]); + + /* Disable port */ + if (link_state == USB_SS_PORT_LS_SS_DISABLED) { + xhci_dbg(xhci, "Disable port %d\n", wIndex); + temp = xhci_port_state_to_neutral(temp); + /* + * Clear all change bits, so that we get a new + * connection event. + */ + temp |= PORT_CSC | PORT_PEC | PORT_WRC | + PORT_OCC | PORT_RC | PORT_PLC | + PORT_CEC; + xhci_writel(xhci, temp | PORT_PE, + port_array[wIndex]); + temp = xhci_readl(xhci, port_array[wIndex]); + break; + } + + /* Put link in RxDetect (enable port) */ + if (link_state == USB_SS_PORT_LS_RX_DETECT) { + xhci_dbg(xhci, "Enable port %d\n", wIndex); + xhci_set_link_state(xhci, port_array, wIndex, + link_state); + temp = xhci_readl(xhci, port_array[wIndex]); + break; + } + /* Software should not attempt to set - * port link state above '5' (Rx.Detect) and the port + * port link state above '3' (U3) and the port * must be enabled. */ if ((temp & PORT_PE) == 0 || - (link_state > USB_SS_PORT_LS_RX_DETECT)) { + (link_state > USB_SS_PORT_LS_U3)) { xhci_warn(xhci, "Cannot set link state.\n"); goto error; } -- cgit v1.2.3 From 77c7f072c87fa951e9a74805febf26466f31170c Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 14 Nov 2012 17:16:52 -0800 Subject: USB: Increase reset timeout. John's NEC 0.96 xHCI host controller needs a longer timeout for a warm reset to complete. The logs show it takes 650ms to complete the warm reset, so extend the hub reset timeout to 800ms to be on the safe side. This commit should be backported to kernels as old as 3.2, that contain the commit 75d7cf72ab9fa01dc70877aa5c68e8ef477229dc "usbcore: refine warm reset logic". Signed-off-by: Sarah Sharp Acked-by: Alan Stern Reported-by: John Covici Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 968ec37a0f02..b9ce5e8bda51 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2499,7 +2499,7 @@ static unsigned hub_is_wusb(struct usb_hub *hub) #define HUB_SHORT_RESET_TIME 10 #define HUB_BH_RESET_TIME 50 #define HUB_LONG_RESET_TIME 200 -#define HUB_RESET_TIMEOUT 500 +#define HUB_RESET_TIMEOUT 800 static int hub_port_reset(struct usb_hub *hub, int port1, struct usb_device *udev, unsigned int delay, bool warm); -- cgit v1.2.3 From 4f43447e62b37ee19c82a13f72f35b1ca60a74d3 Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Thu, 15 Nov 2012 14:58:04 -0800 Subject: USB: Ignore port state until reset completes. The port reset code bails out early if the current connect status is cleared (device disconnected). If we're issuing a hot reset, it may also look at the link state before the reset is finished. Section 10.14.2.6 of the USB 3.0 spec says that when a port enters the Error state or Resetting state, the port connection bit retains the value from the previous state. Therefore we can't trust it until the reset finishes. Also, the xHCI spec section 4.19.1.2.5 says software shall ignore the link state while the port is resetting, as it can be in an unknown state. The port state during reset is also unknown for USB 2.0 hubs. The hub sends a reset signal by driving the bus into an SE0 state. This overwhelms the "connect" signal from the device, so the port can't tell whether anything is connected or not. Fix the port reset code to ignore the port link state and current connect bit until the reset finishes, and USB_PORT_STAT_RESET is cleared. Remove the check for USB_PORT_STAT_C_BH_RESET in the warm reset case, because it's redundant. When the warm reset finishes, the port reset bit will be cleared at the same time USB_PORT_STAT_C_BH_RESET is set. Remove the now-redundant check for a cleared USB_PORT_STAT_RESET bit in the code to deal with the finished reset. This patch should be backported to all stable kernels. Signed-off-by: Sarah Sharp Acked-by: Alan Stern Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index b9ce5e8bda51..42566d774d18 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2534,6 +2534,10 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1, if (ret < 0) return ret; + /* The port state is unknown until the reset completes. */ + if ((portstatus & USB_PORT_STAT_RESET)) + goto delay; + /* * Some buggy devices require a warm reset to be issued even * when the port appears not to be connected. @@ -2579,11 +2583,7 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1, if ((portchange & USB_PORT_STAT_C_CONNECTION)) return -ENOTCONN; - /* if we`ve finished resetting, then break out of - * the loop - */ - if (!(portstatus & USB_PORT_STAT_RESET) && - (portstatus & USB_PORT_STAT_ENABLE)) { + if ((portstatus & USB_PORT_STAT_ENABLE)) { if (hub_is_wusb(hub)) udev->speed = USB_SPEED_WIRELESS; else if (hub_is_superspeed(hub->hdev)) @@ -2597,10 +2597,10 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1, return 0; } } else { - if (portchange & USB_PORT_STAT_C_BH_RESET) - return 0; + return 0; } +delay: /* switch to the long delay after two short delay failures */ if (delay_time >= 2 * HUB_SHORT_RESET_TIME) delay = HUB_LONG_RESET_TIME; -- cgit v1.2.3 From 65bdac5effd15d6af619b3b7218627ef4d84ed6a Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 14 Nov 2012 17:58:04 -0800 Subject: USB: Handle warm reset failure on empty port. An empty port can transition to either Inactive or Compliance Mode if a newly connected USB 3.0 device fails to link train. In that case, we issue a warm reset. Some devices, such as John's Roseweil eusb3 enclosure, slip back into Compliance Mode after the warm reset. The current warm reset code does not check for device connect status on warm reset completion, and it incorrectly reports the warm reset succeeded. This causes the USB core to attempt to send a Set Address control transfer to a port in Compliance Mode, which will always fail. Make hub_port_wait_reset check the current connect status and link state after the warm reset completes. Return a failure status if the device is disconnected or the link state is Compliance Mode or SS.Inactive. Make hub_events disable the port if warm reset fails. This will disable the port, and then bring it back into the RxDetect state. Make the USB core ignore the connect change until the device reconnects. Note that this patch does NOT handle connected devices slipping into the Inactive state very well. This is a concern, because devices can go into the Inactive state on U1/U2 exit failure. However, the fix for that case is too large for stable, so it will be submitted in a separate patch. This patch should be backported to kernels as old as 3.2, contain the commit ID 75d7cf72ab9fa01dc70877aa5c68e8ef477229dc "usbcore: refine warm reset logic" Signed-off-by: Sarah Sharp Acked-by: Alan Stern Reported-by: John Covici Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 42566d774d18..9641e9c1dec5 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2597,6 +2597,11 @@ static int hub_port_wait_reset(struct usb_hub *hub, int port1, return 0; } } else { + if (!(portstatus & USB_PORT_STAT_CONNECTION) || + hub_port_warm_reset_required(hub, + portstatus)) + return -ENOTCONN; + return 0; } @@ -4694,9 +4699,14 @@ static void hub_events(void) * SS.Inactive state. */ if (hub_port_warm_reset_required(hub, portstatus)) { + int status; + dev_dbg(hub_dev, "warm reset port %d\n", i); - hub_port_reset(hub, i, NULL, + status = hub_port_reset(hub, i, NULL, HUB_BH_RESET_TIME, true); + if (status < 0) + hub_port_disable(hub, i, 1); + connect_change = 0; } if (connect_change) -- cgit v1.2.3 From 07e72b95f5038cc82304b9a4a2eb7f9fc391ea68 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Thu, 29 Nov 2012 15:05:57 +0100 Subject: USB: hub: handle claim of enabled remote wakeup after reset Some touchscreens have buggy firmware which claims remote wakeup to be enabled after a reset. They nevertheless crash if the feature is cleared by the host. Add a check for reset resume before checking for an enabled remote wakeup feature. On compliant devices the feature must be cleared after a reset anyway. Signed-off-by: Oliver Neukum Acked-by: Alan Stern Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 9641e9c1dec5..957ed2c41482 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3000,7 +3000,7 @@ int usb_port_suspend(struct usb_device *udev, pm_message_t msg) static int finish_port_resume(struct usb_device *udev) { int status = 0; - u16 devstatus; + u16 devstatus = 0; /* caller owns the udev device lock */ dev_dbg(&udev->dev, "%s\n", @@ -3045,7 +3045,13 @@ static int finish_port_resume(struct usb_device *udev) if (status) { dev_dbg(&udev->dev, "gone after usb resume? status %d\n", status); - } else if (udev->actconfig) { + /* + * There are a few quirky devices which violate the standard + * by claiming to have remote wakeup enabled after a reset, + * which crash if the feature is cleared, hence check for + * udev->reset_resume + */ + } else if (udev->actconfig && !udev->reset_resume) { le16_to_cpus(&devstatus); if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) { status = usb_control_msg(udev, -- cgit v1.2.3