From ae8963adb4ad8c5f2a89ca1d99fb7bb721e7599f Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Wed, 3 Oct 2012 11:18:05 -0700 Subject: usb: Don't enable LPM if the exit latency is zero. Some USB 3.0 devices signal that they don't implement Link PM by having all zeroes in the U1/U2 exit latencies in their SuperSpeed BOS descriptor. Don found that a Western Digital device he has experiences transfer errors when LPM is enabled. The lsusb shows the U1/U2 exit latencies are set to zero: Binary Object Store Descriptor: bLength 5 bDescriptorType 15 wTotalLength 22 bNumDeviceCaps 2 SuperSpeed USB Device Capability: bLength 10 bDescriptorType 16 bDevCapabilityType 3 bmAttributes 0x00 Latency Tolerance Messages (LTM) Supported wSpeedsSupported 0x000e Device can operate at Full Speed (12Mbps) Device can operate at High Speed (480Mbps) Device can operate at SuperSpeed (5Gbps) bFunctionalitySupport 1 Lowest fully-functional device speed is Full Speed (12Mbps) bU1DevExitLat 0 micro seconds bU2DevExitLat 0 micro seconds The fix is to not enable LPM for a particular link state if we find its corresponding exit latency is zero. This patch should be backported to kernels as old as 3.5, that contain the commit 1ea7e0e8e3d0f50901d335ea4178ab2aa8c88201 "USB: Add support to enable/disable USB3 link states." Signed-off-by: Sarah Sharp Reported-by: Don Zickus Tested-by: Don Zickus Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 673ee4696262..8f0478709323 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3415,6 +3415,16 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev, enum usb3_link_state state) { int timeout; + __u8 u1_mel = udev->bos->ss_cap->bU1devExitLat; + __le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat; + + /* If the device says it doesn't have *any* exit latency to come out of + * U1 or U2, it's probably lying. Assume it doesn't implement that link + * state. + */ + if ((state == USB3_LPM_U1 && u1_mel == 0) || + (state == USB3_LPM_U2 && u2_mel == 0)) + return; /* We allow the host controller to set the U1/U2 timeout internally * first, so that it can change its schedule to account for the -- cgit v1.2.3 From 65a95b75bc5afa7bbb844e222481044c1c4767eb Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Fri, 5 Oct 2012 10:32:07 -0700 Subject: usb: Send Set SEL before enabling parent U1/U2 timeout. The Set SEL control transfer tells a device the exit latencies associated with a device-initated U1 or U2 exit. Since a parent hub may initiate a transition to U1 soon after a downstream port's U1 timeout is set, we need to make sure the device receives the Set SEL transfer before the parent hub timeout is set. This patch should be backported to kernels as old as 3.5, that contain the commit 1ea7e0e8e3d0f50901d335ea4178ab2aa8c88201 "USB: Add support to enable/disable USB3 link states." Signed-off-by: Sarah Sharp Cc: stable@vger.kernel.org --- drivers/usb/core/hub.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 8f0478709323..b8e11fff17be 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3319,16 +3319,6 @@ static int usb_set_device_initiated_lpm(struct usb_device *udev, } if (enable) { - /* - * First, let the device know about the exit latencies - * associated with the link state we're about to enable. - */ - ret = usb_req_set_sel(udev, state); - if (ret < 0) { - dev_warn(&udev->dev, "Set SEL for device-initiated " - "%s failed.\n", usb3_lpm_names[state]); - return -EBUSY; - } /* * Now send the control transfer to enable device-initiated LPM * for either U1 or U2. @@ -3414,7 +3404,7 @@ static int usb_set_lpm_timeout(struct usb_device *udev, static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev, enum usb3_link_state state) { - int timeout; + int timeout, ret; __u8 u1_mel = udev->bos->ss_cap->bU1devExitLat; __le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat; @@ -3426,6 +3416,17 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev, (state == USB3_LPM_U2 && u2_mel == 0)) return; + /* + * First, let the device know about the exit latencies + * associated with the link state we're about to enable. + */ + ret = usb_req_set_sel(udev, state); + if (ret < 0) { + dev_warn(&udev->dev, "Set SEL for device-initiated %s failed.\n", + usb3_lpm_names[state]); + return; + } + /* We allow the host controller to set the U1/U2 timeout internally * first, so that it can change its schedule to account for the * additional latency to send data to a device in a lower power -- cgit v1.2.3 From 1510a1a2d0946b34422fe8816187f274a5086904 Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Fri, 5 Oct 2012 10:30:35 -0700 Subject: usb: trival: Fix debugging units mistake. SEL and PEL are in microseconds, not milliseconds. Also, fix a split string that will trigger checkpatch warnings. Signed-off-by: Sarah Sharp --- drivers/usb/core/hub.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/usb/core/hub.c') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index b8e11fff17be..64854d76f529 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3241,8 +3241,7 @@ static int usb_req_set_sel(struct usb_device *udev, enum usb3_link_state state) (state == USB3_LPM_U2 && (u2_sel > USB3_LPM_MAX_U2_SEL_PEL || u2_pel > USB3_LPM_MAX_U2_SEL_PEL))) { - dev_dbg(&udev->dev, "Device-initiated %s disabled due " - "to long SEL %llu ms or PEL %llu ms\n", + dev_dbg(&udev->dev, "Device-initiated %s disabled due to long SEL %llu us or PEL %llu us\n", usb3_lpm_names[state], u1_sel, u1_pel); return -EINVAL; } -- cgit v1.2.3 From 3b6054da68f9b0d5ed6a7ed0f42a79e61904352c Mon Sep 17 00:00:00 2001 From: Octavian Purdila Date: Mon, 1 Oct 2012 22:21:12 +0300 Subject: usb hub: send clear_tt_buffer_complete events when canceling TT clear work There is a race condition in the USB hub code with regard to handling TT clear requests that can get the HCD driver in a deadlock. Usually when an TT clear request is scheduled it will be executed immediately: <7>[ 6.077583] usb 2-1.3: unlink qh1-0e01/f4d4db00 start 0 [1/2 us] <3>[ 6.078041] usb 2-1: clear tt buffer port 3, a3 ep2 t04048d82 <7>[ 6.078299] hub_tt_work:731 <7>[ 9.309089] usb 2-1.5: link qh1-0e01/f4d506c0 start 0 [1/2 us] <7>[ 9.324526] ehci_hcd 0000:00:1d.0: reused qh f4d4db00 schedule <7>[ 9.324539] usb 2-1.3: link qh1-0e01/f4d4db00 start 0 [1/2 us] <7>[ 9.341530] usb 1-1.1: link qh4-0e01/f397aec0 start 2 [1/2 us] <7>[ 10.116159] usb 2-1.3: unlink qh1-0e01/f4d4db00 start 0 [1/2 us] <3>[ 10.116459] usb 2-1: clear tt buffer port 3, a3 ep2 t04048d82 <7>[ 10.116537] hub_tt_work:731 However, if a suspend operation is triggered before hub_tt_work is scheduled, hub_quiesce will cancel the work without notifying the HCD driver: <3>[ 35.033941] usb 2-1: clear tt buffer port 3, a3 ep2 t04048d80 <5>[ 35.034022] sd 0:0:0:0: [sda] Stopping disk <7>[ 35.034039] hub 2-1:1.0: hub_suspend <7>[ 35.034067] usb 2-1: unlink qh256-0001/f3b1ab00 start 1 [1/0 us] <7>[ 35.035085] hub 1-0:1.0: hub_suspend <7>[ 35.035102] usb usb1: bus suspend, wakeup 0 <7>[ 35.035106] ehci_hcd 0000:00:1a.0: suspend root hub <7>[ 35.035298] hub 2-0:1.0: hub_suspend <7>[ 35.035313] usb usb2: bus suspend, wakeup 0 <7>[ 35.035315] ehci_hcd 0000:00:1d.0: suspend root hub <6>[ 35.250017] PM: suspend of devices complete after 216.979 msecs <6>[ 35.250822] PM: late suspend of devices complete after 0.799 msecs <7>[ 35.252343] ehci_hcd 0000:00:1d.0: wakeup: 1 <7>[ 35.262923] ehci_hcd 0000:00:1d.0: --> PCI D3hot <7>[ 35.263302] ehci_hcd 0000:00:1a.0: wakeup: 1 <7>[ 35.273912] ehci_hcd 0000:00:1a.0: --> PCI D3hot <6>[ 35.274254] PM: noirq suspend of devices complete after 23.442 msecs <6>[ 35.274975] ACPI: Preparing to enter system sleep state S3 <6>[ 35.292666] PM: Saving platform NVS memory <7>[ 35.295030] Disabling non-boot CPUs ... <6>[ 35.297351] CPU 1 is now offline <6>[ 35.300345] CPU 2 is now offline <6>[ 35.303929] CPU 3 is now offline <7>[ 35.303931] lockdep: fixing up alternatives. <6>[ 35.304825] Extended CMOS year: 2000 When the device will resume the EHCI driver will get stuck in ehci_endpoint_disable waiting for the tt_clearing flag to reset: <0>[ 47.610967] usb 2-1.3: **** DPM device timeout **** <7>[ 47.610972] f2f11c60 00000092 f2f11c0c c10624a5 00000003 f4c6e880 c1c8a4c0 c1c8a4c0 <7>[ 47.610983] 15c55698 0000000b f56b34c0 f2a45b70 f4c6e880 00000082 f2a4602c f2f11c30 <7>[ 47.610993] c10787f8 f4cac000 f2a45b70 00000000 f4cac010 f2f11c58 00000046 00000001 <7>[ 47.611004] Call Trace: <7>[ 47.611006] [] ? sched_clock_cpu+0xf5/0x160 <7>[ 47.611019] [] ? lock_release_holdtime.part.22+0x88/0xf0 <7>[ 47.611026] [] ? lock_timer_base.isra.35+0x26/0x50 <7>[ 47.611034] [] ? schedule_timeout+0x133/0x290 <7>[ 47.611044] [] schedule+0x1e/0x50 <7>[ 47.611051] [] schedule_timeout+0x138/0x290 <7>[ 47.611057] [] ? sched_clock_cpu+0xf5/0x160 <7>[ 47.611063] [] ? usleep_range+0x40/0x40 <7>[ 47.611070] [] schedule_timeout_uninterruptible+0x15/0x20 <7>[ 47.611077] [] ehci_endpoint_disable+0x64/0x160 <7>[ 47.611084] [] ? usb_hcd_flush_endpoint+0x10e/0x1d0 <7>[ 47.611092] [] ? sysfs_add_file+0x13/0x20 <7>[ 47.611100] [] usb_hcd_disable_endpoint+0x29/0x40 <7>[ 47.611107] [] usb_disable_endpoint+0x5c/0x80 <7>[ 47.611111] [] usb_disable_interface+0x37/0x50 <7>[ 47.611116] [] usb_reset_and_verify_device+0x4b0/0x640 <7>[ 47.611122] [] ? hub_port_status+0xb5/0x100 <7>[ 47.611129] [] usb_port_resume+0xd5/0x220 <7>[ 47.611136] [] generic_resume+0xf/0x30 <7>[ 47.611142] [] usb_resume+0x133/0x180 <7>[ 47.611147] [] ? usb_dev_thaw+0x10/0x10 <7>[ 47.611152] [] usb_dev_resume+0xd/0x10 <7>[ 47.611157] [] dpm_run_callback+0x40/0xb0 <7>[ 47.611164] [] ? pm_runtime_enable+0x43/0x70 <7>[ 47.611171] [] device_resume+0x1a6/0x2c0 <7>[ 47.611177] [] ? dpm_show_time+0xe0/0xe0 <7>[ 47.611183] [] async_resume+0x19/0x40 <7>[ 47.611189] [] async_run_entry_fn+0x64/0x160 <7>[ 47.611196] [] ? process_one_work+0x104/0x480 <7>[ 47.611203] [] ? process_one_work+0x10c/0x480 <7>[ 47.611209] [] process_one_work+0x180/0x480 <7>[ 47.611215] [] ? process_one_work+0x104/0x480 <7>[ 47.611220] [] ? async_schedule+0x10/0x10 <7>[ 47.611226] [] worker_thread+0x11c/0x2f0 <7>[ 47.611233] [] ? manage_workers.isra.27+0x1f0/0x1f0 <7>[ 47.611239] [] kthread+0x78/0x80 <7>[ 47.611244] [] ? timer_cpu_notify+0xd6/0x20d <7>[ 47.611253] [] ? __init_kthread_worker+0x60/0x60 <7>[ 47.611258] [] kernel_thread_helper+0x6/0xd <7>[ 47.611283] ------------[ cut here ]------------ This patch changes hub_quiesce behavior to flush the TT clear work instead of canceling it, to make sure that no TT clear request remains uncompleted before suspend. Signed-off-by: Octavian Purdila Acked-by: Alan Stern Cc: stable 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 64854d76f529..1181e917fec7 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -739,13 +739,16 @@ static void hub_tt_work(struct work_struct *work) int limit = 100; spin_lock_irqsave (&hub->tt.lock, flags); - while (--limit && !list_empty (&hub->tt.clear_list)) { + while (!list_empty(&hub->tt.clear_list)) { struct list_head *next; struct usb_tt_clear *clear; struct usb_device *hdev = hub->hdev; const struct hc_driver *drv; int status; + if (!hub->quiescing && --limit < 0) + break; + next = hub->tt.clear_list.next; clear = list_entry (next, struct usb_tt_clear, clear_list); list_del (&clear->clear_list); @@ -1210,7 +1213,7 @@ static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type) if (hub->has_indicators) cancel_delayed_work_sync(&hub->leds); if (hub->tt.hub) - cancel_work_sync(&hub->tt.clear_work); + flush_work_sync(&hub->tt.clear_work); } /* caller has locked the hub device */ -- cgit v1.2.3 From 036546bf950b7916dcc051eb0d450e23028b487a Mon Sep 17 00:00:00 2001 From: Octavian Purdila Date: Tue, 23 Oct 2012 11:33:12 +0300 Subject: usb hub: use flush_work instead of flush_work_sync flush_work_sync and flush_work are now the same and flush_work_sync has been deprecated. This fixes the following warning: drivers/usb/core/hub.c: In function hub_quiesce: drivers/usb/core/hub.c:1216:3: warning: flush_work_sync is deprecated (declared at include/linux/workqueue.h:448) [-Wdeprecated-declarations] Reported-by: Fengguang Wu Signed-off-by: Octavian Purdila Signed-off-by: Greg Kroah-Hartman --- 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 1181e917fec7..1af04bdeaf0c 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -1213,7 +1213,7 @@ static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type) if (hub->has_indicators) cancel_delayed_work_sync(&hub->leds); if (hub->tt.hub) - flush_work_sync(&hub->tt.clear_work); + flush_work(&hub->tt.clear_work); } /* caller has locked the hub device */ -- cgit v1.2.3