From 9faabe06dc80976e8b92111bad772dd5edecb10f Mon Sep 17 00:00:00 2001 From: "Lee, Chiasheng" Date: Thu, 20 Jun 2019 10:56:04 +0300 Subject: usb: Handle USB3 remote wakeup for LPM enabled devices correctly commit e244c4699f859cf7149b0781b1894c7996a8a1df upstream. With Link Power Management (LPM) enabled USB3 links transition to low power U1/U2 link states from U0 state automatically. Current hub code detects USB3 remote wakeups by checking if the software state still shows suspended, but the link has transitioned from suspended U3 to enabled U0 state. As it takes some time before the hub thread reads the port link state after a USB3 wake notification, the link may have transitioned from U0 to U1/U2, and wake is not detected by hub code. Fix this by handling U1/U2 states in the same way as U0 in USB3 wakeup handling This patch should be added to stable kernels since 4.13 where LPM was kept enabled during suspend/resume Cc: # v4.13+ Signed-off-by: Lee, Chiasheng Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 7 +++++-- 1 file changed, 5 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 eddecaf1f0b2..2e1e7399596e 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3532,6 +3532,7 @@ static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port, struct usb_device *hdev; struct usb_device *udev; int connect_change = 0; + u16 link_state; int ret; hdev = hub->hdev; @@ -3541,9 +3542,11 @@ static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port, return 0; usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND); } else { + link_state = portstatus & USB_PORT_STAT_LINK_STATE; if (!udev || udev->state != USB_STATE_SUSPENDED || - (portstatus & USB_PORT_STAT_LINK_STATE) != - USB_SS_PORT_LS_U0) + (link_state != USB_SS_PORT_LS_U0 && + link_state != USB_SS_PORT_LS_U1 && + link_state != USB_SS_PORT_LS_U2)) return 0; } -- cgit v1.2.3 From 268e63c810fd542217cf2af2a3113bfd459e60a5 Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Tue, 14 May 2019 14:38:38 -0700 Subject: usb: core: hub: Disable hub-initiated U1/U2 [ Upstream commit 561759292774707b71ee61aecc07724905bb7ef1 ] If the device rejects the control transfer to enable device-initiated U1/U2 entry, then the device will not initiate U1/U2 transition. To improve the performance, the downstream port should not initate transition to U1/U2 to avoid the delay from the device link command response (no packet can be transmitted while waiting for a response from the device). If the device has some quirks and does not implement U1/U2, it may reject all the link state change requests, and the downstream port may resend and flood the bus with more requests. This will affect the device performance even further. This patch disables the hub-initated U1/U2 if the device-initiated U1/U2 entry fails. Reference: USB 3.2 spec 7.2.4.2.3 Signed-off-by: Thinh Nguyen Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/core/hub.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 2e1e7399596e..b543a4730ef2 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3876,6 +3876,9 @@ static int usb_set_lpm_timeout(struct usb_device *udev, * control transfers to set the hub timeout or enable device-initiated U1/U2 * will be successful. * + * If the control transfer to enable device-initiated U1/U2 entry fails, then + * hub-initiated U1/U2 will be disabled. + * * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI * driver know about it. If that call fails, it should be harmless, and just * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency. @@ -3930,23 +3933,24 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev, * host know that this link state won't be enabled. */ hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state); - } else { - /* Only a configured device will accept the Set Feature - * U1/U2_ENABLE - */ - if (udev->actconfig) - usb_set_device_initiated_lpm(udev, state, true); + return; + } - /* As soon as usb_set_lpm_timeout(timeout) returns 0, the - * hub-initiated LPM is enabled. Thus, LPM is enabled no - * matter the result of usb_set_device_initiated_lpm(). - * The only difference is whether device is able to initiate - * LPM. - */ + /* Only a configured device will accept the Set Feature + * U1/U2_ENABLE + */ + if (udev->actconfig && + usb_set_device_initiated_lpm(udev, state, true) == 0) { if (state == USB3_LPM_U1) udev->usb3_lpm_u1_enabled = 1; else if (state == USB3_LPM_U2) udev->usb3_lpm_u2_enabled = 1; + } else { + /* Don't request U1/U2 entry if the device + * cannot transition to U1/U2. + */ + usb_set_lpm_timeout(udev, state, 0); + hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state); } } -- cgit v1.2.3 From e9d94c641a1f9143dc9b187d3300d5f11f006860 Mon Sep 17 00:00:00 2001 From: Jan-Marek Glogowski Date: Fri, 1 Feb 2019 13:52:31 +0100 Subject: usb: handle warm-reset port requests on hub resume [ Upstream commit 4fdc1790e6a9ef22399c6bc6e63b80f4609f3b7e ] On plug-in of my USB-C device, its USB_SS_PORT_LS_SS_INACTIVE link state bit is set. Greping all the kernel for this bit shows that the port status requests a warm-reset this way. This just happens, if its the only device on the root hub, the hub therefore resumes and the HCDs status_urb isn't yet available. If a warm-reset request is detected, this sets the hubs event_bits, which will prevent any auto-suspend and allows the hubs workqueue to warm-reset the port later in port_event. Signed-off-by: Jan-Marek Glogowski Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/core/hub.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index b543a4730ef2..bb20aa433e98 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -104,6 +104,8 @@ EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem); static void hub_release(struct kref *kref); static int usb_reset_and_verify_device(struct usb_device *udev); static int hub_port_disable(struct usb_hub *hub, int port1, int set_state); +static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1, + u16 portstatus); static inline char *portspeed(struct usb_hub *hub, int portstatus) { @@ -1110,6 +1112,11 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type) USB_PORT_FEAT_ENABLE); } + /* Make sure a warm-reset request is handled by port_event */ + if (type == HUB_RESUME && + hub_port_warm_reset_required(hub, port1, portstatus)) + set_bit(port1, hub->event_bits); + /* * Add debounce if USB3 link is in polling/link training state. * Link will automatically transition to Enabled state after -- cgit v1.2.3 From b394c7780773890ca1ad0bc50a9e5d52805f36bb Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Wed, 6 Nov 2019 14:27:10 +0800 Subject: usb: Allow USB device to be warm reset in suspended state commit e76b3bf7654c3c94554c24ba15a3d105f4006c80 upstream. On Dell WD15 dock, sometimes USB ethernet cannot be detected after plugging cable to the ethernet port, the hub and roothub get runtime resumed and runtime suspended immediately: ... [ 433.315169] xhci_hcd 0000:3a:00.0: hcd_pci_runtime_resume: 0 [ 433.315204] usb usb4: usb auto-resume [ 433.315226] hub 4-0:1.0: hub_resume [ 433.315239] xhci_hcd 0000:3a:00.0: Get port status 4-1 read: 0x10202e2, return 0x10343 [ 433.315264] usb usb4-port1: status 0343 change 0001 [ 433.315279] xhci_hcd 0000:3a:00.0: clear port1 connect change, portsc: 0x10002e2 [ 433.315293] xhci_hcd 0000:3a:00.0: Get port status 4-2 read: 0x2a0, return 0x2a0 [ 433.317012] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.422282] xhci_hcd 0000:3a:00.0: Get port status 4-1 read: 0x10002e2, return 0x343 [ 433.422307] usb usb4-port1: do warm reset [ 433.422311] usb 4-1: device reset not allowed in state 8 [ 433.422339] hub 4-0:1.0: state 7 ports 2 chg 0002 evt 0000 [ 433.422346] xhci_hcd 0000:3a:00.0: Get port status 4-1 read: 0x10002e2, return 0x343 [ 433.422356] usb usb4-port1: do warm reset [ 433.422358] usb 4-1: device reset not allowed in state 8 [ 433.422428] xhci_hcd 0000:3a:00.0: set port remote wake mask, actual port 0 status = 0xf0002e2 [ 433.422455] xhci_hcd 0000:3a:00.0: set port remote wake mask, actual port 1 status = 0xe0002a0 [ 433.422465] hub 4-0:1.0: hub_suspend [ 433.422475] usb usb4: bus auto-suspend, wakeup 1 [ 433.426161] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.466209] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.510204] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.554051] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.598235] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.642154] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.686204] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.730205] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.774203] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.818207] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.862040] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.862053] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.862077] xhci_hcd 0000:3a:00.0: xhci_suspend: stopping port polling. [ 433.862096] xhci_hcd 0000:3a:00.0: // Setting command ring address to 0x8578fc001 [ 433.862312] xhci_hcd 0000:3a:00.0: hcd_pci_runtime_suspend: 0 [ 433.862445] xhci_hcd 0000:3a:00.0: PME# enabled [ 433.902376] xhci_hcd 0000:3a:00.0: restoring config space at offset 0xc (was 0x0, writing 0x20) [ 433.902395] xhci_hcd 0000:3a:00.0: restoring config space at offset 0x4 (was 0x100000, writing 0x100403) [ 433.902490] xhci_hcd 0000:3a:00.0: PME# disabled [ 433.902504] xhci_hcd 0000:3a:00.0: enabling bus mastering [ 433.902547] xhci_hcd 0000:3a:00.0: // Setting command ring address to 0x8578fc001 [ 433.902649] pcieport 0000:00:1b.0: PME: Spurious native interrupt! [ 433.902839] xhci_hcd 0000:3a:00.0: Port change event, 4-1, id 3, portsc: 0xb0202e2 [ 433.902842] xhci_hcd 0000:3a:00.0: resume root hub [ 433.902845] xhci_hcd 0000:3a:00.0: handle_port_status: starting port polling. [ 433.902877] xhci_hcd 0000:3a:00.0: xhci_resume: starting port polling. [ 433.902889] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.902891] xhci_hcd 0000:3a:00.0: hcd_pci_runtime_resume: 0 [ 433.902919] usb usb4: usb wakeup-resume [ 433.902942] usb usb4: usb auto-resume [ 433.902966] hub 4-0:1.0: hub_resume ... As Mathias pointed out, the hub enters Cold Attach Status state and requires a warm reset. However usb_reset_device() bails out early when the device is in suspended state, as its callers port_event() and hub_event() don't always resume the device. Since there's nothing wrong to reset a suspended device, allow usb_reset_device() to do so to solve the issue. Signed-off-by: Kai-Heng Feng Acked-by: Alan Stern Cc: stable Link: https://lore.kernel.org/r/20191106062710.29880-1-kai.heng.feng@canonical.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 5 ++--- 1 file changed, 2 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 bb20aa433e98..4efccf8bf99f 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -5630,7 +5630,7 @@ re_enumerate_no_bos: /** * usb_reset_device - warn interface drivers and perform a USB port reset - * @udev: device to reset (not in SUSPENDED or NOTATTACHED state) + * @udev: device to reset (not in NOTATTACHED state) * * Warns all drivers bound to registered interfaces (using their pre_reset * method), performs the port reset, and then lets the drivers know that @@ -5658,8 +5658,7 @@ int usb_reset_device(struct usb_device *udev) struct usb_host_config *config = udev->actconfig; struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent); - if (udev->state == USB_STATE_NOTATTACHED || - udev->state == USB_STATE_SUSPENDED) { + if (udev->state == USB_STATE_NOTATTACHED) { dev_dbg(&udev->dev, "device reset not allowed in state %d\n", udev->state); return -EINVAL; -- cgit v1.2.3