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path: root/drivers/usb/core/hub.c
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2013-01-24usb: Using correct way to clear usb3.0 device's remote wakeup feature.Lan Tianyu1-18/+52
Usb3.0 device defines function remote wakeup which is only for interface recipient rather than device recipient. This is different with usb2.0 device's remote wakeup feature which is defined for device recipient. According usb3.0 spec 9.4.5, the function remote wakeup can be modified by the SetFeature() requests using the FUNCTION_SUSPEND feature selector. This patch is to use correct way to disable usb3.0 device's function remote wakeup after suspend error and resuming. This should be backported to kernels as old as 3.4, that contain the commit 623bef9e03a60adc623b09673297ca7a1cdfb367 "USB/xhci: Enable remote wakeup for USB3 devices." Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org
2013-01-11USB: hub: handle claim of enabled remote wakeup after resetOliver Neukum1-2/+8
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 <oneukum@suse.de> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03USB: Handle warm reset failure on empty port.Sarah Sharp1-1/+11
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 <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: John Covici <covici@ccs.covici.com> Cc: stable@vger.kernel.org
2013-01-03USB: Ignore port state until reset completes.Sarah Sharp1-7/+7
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 <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable@vger.kernel.org
2013-01-03USB: Increase reset timeout.Sarah Sharp1-1/+1
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 <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: John Covici <covici@ccs.covici.com> Cc: stable@vger.kernel.org
2013-01-03USB: Allow USB 3.0 ports to be disabled.Sarah Sharp1-2/+61
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 <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: John Covici <covici@ccs.covici.com> Cc: stable@vger.kernel.org
2013-01-03USB: Ignore xHCI Reset Device status.Sarah Sharp1-8/+5
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 <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable@vger.kernel.org
2013-01-03USB: Handle auto-transition from hot to warm reset.Sarah Sharp1-3/+3
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 <sarah.a.sharp@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable@vger.kernel.org
2012-11-15usb: phy: change phy notify connect/disconnect APIPeter Chen1-2/+2
The old parameter "port" is useless for phy notify, as one usb phy is only for one usb port. New parameter "speed" stands for the device's speed which is on the port, this "speed" parameter is needed at some platforms which will do some phy operations according to device's speed. Signed-off-by: Peter Chen <peter.chen@freescale.com> Tested-by: Mike Thompson <mpthompson@gmail.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-15usb: refine phy notify operation during connection and disconnectionPeter Chen1-8/+8
At commit 925aa46ba963a4da6d8ee6ab1d04a02ffa8db62b, Richard Zhao <richard.zhao@freescale.com> adds the phy notification callback when port change occurs. In fact, this phy notification should be added according to below rules: 1. Only set HW_USBPHY_CTRL.ENHOSTDISCONDETECT during high speed host mode. 2. Do not set HW_USBPHY_CTRL.ENHOSTDISCONDETECT during the reset and speed negotiation period. 3. Do not set HW_USBPHY_CTRL.ENHOSTDISCONDETECT during host suspend/resume sequence. Please refer: i.mx23RM(page: 413) for below rules. http://www.freescale.com/files/dsp/doc/ref_manual/IMX23RM.pdf Freescale i.MX SoC, i.mx23, i.mx28 and i.mx6(i.mx6SL does not need to follow the 3rd rule) need to follow above rules. Current code set connect notification (HW_USBPHY_CTRL.ENHOSTDISCONDETECT) at hub_port_connect_change, it conflicts with above the 2th rule. The correct notification setting method should be: 1. Set connect notify after the second bus reset. 2. Set disconnect notify after disconnection. Signed-off-by: Peter Chen <peter.chen@freescale.com> Tested-by: Mike Thompson <mpthompson@gmail.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31USB: remove iteration limit in hub_tt_work()Alan Stern1-4/+0
This patch (as1621) removes the limit on the number of loops allowed in hub_tt_work(). The value is arbitrary, and it's silly to have a limit in the first place -- anything beyond the limit would not get handled. Besides, it's most unlikely that we'll ever need to clear more than a couple of TT buffers at any time. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-30usb: Convert dev_printk(KERN_<LEVEL> to dev_<level>(Joe Perches1-1/+1
dev_<level> calls take less code than dev_printk(KERN_<LEVEL> and reducing object size is good. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-29Merge 3.7-rc3 into usb-next.Greg Kroah-Hartman1-2/+5
This pulls in all of the USB changes in 3.7-rc3 into usb-next and resolves the merge issue with: drivers/usb/misc/ezusb.c Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25USB: set hub's default autosuspend delay as 0Ming Lei1-0/+35
This patch sets hub device's default autosuspend delay as 0 to speedup bus suspend, see comments in code for details. Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-25USB: check port changes before hub runtime suspend for some bug deviceMing Lei1-0/+38
The hub status endpoint has a long 'bInterval', which is 255ms for FS/LS device and 256ms for HS device according to USB 2.0 spec, so the device connection change may be reported later more than 255ms via status pipe. The connection change in hub may have been happened already on the downstream ports, but no status URB completes when it is killed in hub_suspend(auto), so the connection change may be missed by some buggy hub devices, which won't generate remote wakeup signal after their remote wakeup is enabled and they are put into suspend state. The problem can be observed at least on the below Genesys Logic, Inc. hub devices: 0x05e3,0x0606 0x05e3,0x0608 In theory, there is no way to fix the problem completely, but we can make it less likely to occur by this patch. This patch introduces one quirk of HUB_QUIRK_CHECK_PORTS_AUTOSUSPEND to check ports' change during hub_suspend(auto) for the buggy devices. If ports' change is found, terminate the auto suspend and return to working state. So for the buggy hubs, if the connection change happend before the ports' check, it can be handled correctly. If it happens between the ports' check and enabling remote wakeup/entering suspend, it will be missed. Considered the interval is quite short, it is very less likely to happen during the window. Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-24USB: speed up usb_bus_resume()Alan Stern1-0/+2
This patch (as1620) speeds up USB root-hub resumes in the common case where every enabled port has its suspend feature set (which currently will be true for every runtime resume of the root hub). If all the enabled ports are suspended then resuming the root hub won't resume any of the downstream devices. In this case there's no need for a Resume Recovery delay, because that delay is meant to give devices a chance to get ready for active use. To keep track of the port suspend features, the patch adds a "port_is_suspended" flag to struct usb_device. This has to be tracked separately from the device's state; it's entirely possible for a USB-2 device to be suspended while the suspend feature on its parent port is clear. The reason is that devices will go into suspend whenever their parent hub does. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reviewed-by: Peter Chen <peter.chen@freescale.com> Tested-by: Peter Chen <peter.chen@freescale.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-23usb hub: use flush_work instead of flush_work_syncOctavian Purdila1-1/+1
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 <fengguang.wu@intel.com> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-22usb hub: send clear_tt_buffer_complete events when canceling TT clear workOctavian Purdila1-2/+5
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] [<c10624a5>] ? sched_clock_cpu+0xf5/0x160 <7>[ 47.611019] [<c10787f8>] ? lock_release_holdtime.part.22+0x88/0xf0 <7>[ 47.611026] [<c103ed46>] ? lock_timer_base.isra.35+0x26/0x50 <7>[ 47.611034] [<c17592d3>] ? schedule_timeout+0x133/0x290 <7>[ 47.611044] [<c175b43e>] schedule+0x1e/0x50 <7>[ 47.611051] [<c17592d8>] schedule_timeout+0x138/0x290 <7>[ 47.611057] [<c10624a5>] ? sched_clock_cpu+0xf5/0x160 <7>[ 47.611063] [<c103e560>] ? usleep_range+0x40/0x40 <7>[ 47.611070] [<c1759445>] schedule_timeout_uninterruptible+0x15/0x20 <7>[ 47.611077] [<c14935f4>] ehci_endpoint_disable+0x64/0x160 <7>[ 47.611084] [<c147d1ee>] ? usb_hcd_flush_endpoint+0x10e/0x1d0 <7>[ 47.611092] [<c1165663>] ? sysfs_add_file+0x13/0x20 <7>[ 47.611100] [<c147d5a9>] usb_hcd_disable_endpoint+0x29/0x40 <7>[ 47.611107] [<c147fafc>] usb_disable_endpoint+0x5c/0x80 <7>[ 47.611111] [<c147fb57>] usb_disable_interface+0x37/0x50 <7>[ 47.611116] [<c1477650>] usb_reset_and_verify_device+0x4b0/0x640 <7>[ 47.611122] [<c1474665>] ? hub_port_status+0xb5/0x100 <7>[ 47.611129] [<c147a975>] usb_port_resume+0xd5/0x220 <7>[ 47.611136] [<c148877f>] generic_resume+0xf/0x30 <7>[ 47.611142] [<c14821a3>] usb_resume+0x133/0x180 <7>[ 47.611147] [<c1473b10>] ? usb_dev_thaw+0x10/0x10 <7>[ 47.611152] [<c1473b1d>] usb_dev_resume+0xd/0x10 <7>[ 47.611157] [<c13baa60>] dpm_run_callback+0x40/0xb0 <7>[ 47.611164] [<c13bdb03>] ? pm_runtime_enable+0x43/0x70 <7>[ 47.611171] [<c13bafc6>] device_resume+0x1a6/0x2c0 <7>[ 47.611177] [<c13ba940>] ? dpm_show_time+0xe0/0xe0 <7>[ 47.611183] [<c13bb0f9>] async_resume+0x19/0x40 <7>[ 47.611189] [<c10580c4>] async_run_entry_fn+0x64/0x160 <7>[ 47.611196] [<c104a244>] ? process_one_work+0x104/0x480 <7>[ 47.611203] [<c104a24c>] ? process_one_work+0x10c/0x480 <7>[ 47.611209] [<c104a2c0>] process_one_work+0x180/0x480 <7>[ 47.611215] [<c104a244>] ? process_one_work+0x104/0x480 <7>[ 47.611220] [<c1058060>] ? async_schedule+0x10/0x10 <7>[ 47.611226] [<c104c15c>] worker_thread+0x11c/0x2f0 <7>[ 47.611233] [<c104c040>] ? manage_workers.isra.27+0x1f0/0x1f0 <7>[ 47.611239] [<c10507f8>] kthread+0x78/0x80 <7>[ 47.611244] [<c1750000>] ? timer_cpu_notify+0xd6/0x20d <7>[ 47.611253] [<c1050780>] ? __init_kthread_worker+0x60/0x60 <7>[ 47.611258] [<c176357e>] 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 <octavian.purdila@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-08usb: trival: Fix debugging units mistake.Sarah Sharp1-2/+1
SEL and PEL are in microseconds, not milliseconds. Also, fix a split string that will trigger checkpatch warnings. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-10-08usb: Send Set SEL before enabling parent U1/U2 timeout.Sarah Sharp1-11/+12
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 <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org
2012-10-08usb: Don't enable LPM if the exit latency is zero.Sarah Sharp1-0/+10
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 <sarah.a.sharp@linux.intel.com> Reported-by: Don Zickus <dzickus@redhat.com> Tested-by: Don Zickus <dzickus@redhat.com> Cc: stable@vger.kernel.org
2012-09-24Revert "usb : Add sysfs files to control port power."Greg Kroah-Hartman1-132/+1
This reverts commit ca9c9d0c922e4f1dac80699ebab1269d6dbaff85. Rafael wants more time to work on the user api to handle port power issues, so let's just revert the sysfs changes for now. Reported-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Lan Tianyu <tianyu.lan@intel.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-12usb: move children deallocation after quiescing the hubAlexander Shishkin1-3/+3
Commit ff823c79a5c33194c2e5594f7c4686ea3547910c ("usb: move children to struct usb_port") forgot to consider the hub_disconnect sequence, which releases ports before quiescing the hub, which will lead to a use-after-free, since hub_quiesce() will try to disconnect ports' children, which are already deallocated. Simple modprobe dummy_hcd && rmmod dummy_hcd will illustrate the problem. This patch moves deallocation of hub's ports after hub_quiesce() call in hub_disconnect(). Cc: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10usb: add little-endian transform for DeviceRemovable of usb3.0 hubLan Tianyu1-1/+2
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10usb : Add sysfs files to control port power.Lan Tianyu1-1/+132
This patch adds two sysfs files for each usb hub port to allow userspace to control the port power policy. For an upcoming Intel xHCI roothub, this will translate into ACPI calls to completely power off or power on the port. As a reminder, when these ports are completely powered off, the USB host and device will see a physical disconnect. All future USB device connections will be lost, and the device will not be able to signal a remote wakeup. The control sysfs file can be written to with two options: "on" - port power must be on. "off" - port must be off. The state sysfs file reports usb port's power state: "on" - powered on "off" - powered off "error" - can't get power state For now, let userspace dictate the port power off policy. Future patches may add an in-kernel policy. Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10usb/acpi: Store info on device removability.Lan Tianyu1-0/+31
In the upcoming USB port power off patches, we need to know whether a USB port can ever see a disconnect event. Often USB ports are internal to a system, and users can't disconnect USB devices from that port. Sometimes those ports will remain empty, because the OEM chose not to connect an internal USB device to that port. According to ACPI Spec 9.13, PLD indicates whether USB port is user visible and _UPC indicates whether a USB device can be connected to the USB port (we'll call this "connectible"). Here's a matrix of the possible combinations: Visible Connectible Name Example ------------------------------------------------------------------------- Yes No Unknown (Invalid state.) Yes Yes Hot-plug USB ports on the outside of a laptop. A user could freely connect and disconnect USB devices. No Yes Hard-wired A USB modem hard-wired to a port on the inside of a laptop. No No Not used The port is internal to the system and will remain empty. Represent each of these four states with an enum usb_port_connect_type. The four states are USB_PORT_CONNECT_TYPE_UNKNOWN, USB_PORT_CONNECT_TYPE_HOT_PLUG, USB_PORT_CONNECT_TYPE_HARD_WIRED, and USB_PORT_NOT_USED. When we get the USB port's acpi_handle, store the state in connect_type in struct usb_port. Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10usb/acpi: Bind ACPI node to USB port, not usb_device.Lan Tianyu1-0/+18
In the ACPI DSDT table, only usb root hub and usb ports are ACPI device nodes. Originally, we bound the usb port's ACPI node to the usb device attached to the port. However, we want to access those ACPI port methods when the port is empty, and there's no usb_device associated with that port. Now that the usb port is a real device, we can bind the port's ACPI node to struct usb_port instead. Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10usb: move children to struct usb_portLan Tianyu1-24/+49
The usb_device structure contains an array of usb_device "children". This array is only valid if the usb_device is a hub, so it makes no sense to store it there. Instead, store the usb_device child in its parent usb_port structure. Since usb_port is an internal USB core structure, add a new function to get the USB device child, usb_hub_find_child(). Add a new macro, usb_hub_get_each_child(), to iterate over all the children attached to a particular USB hub. Remove the printing the USB children array pointer from the usb-ip driver, since it's really not necessary. Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-10usb: make usb port a real deviceLan Tianyu1-16/+75
This patch turns each USB port on a hub into a new struct device. This new device has the USB hub interface device as its parent. The port devices are stored in a new structure (usb_port), and an array of usb_ports are dynamically allocated once we know how many ports the USB hub has. Move the port_owner variable out of usb_hub and into this new structure. A new file will be created in the hub interface sysfs directory, so add documentation. Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-31Merge tag 'random_for_linus' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull random subsystem patches from Ted Ts'o: "This patch series contains a major revamp of how we collect entropy from interrupts for /dev/random and /dev/urandom. The goal is to addresses weaknesses discussed in the paper "Mining your Ps and Qs: Detection of Widespread Weak Keys in Network Devices", by Nadia Heninger, Zakir Durumeric, Eric Wustrow, J. Alex Halderman, which will be published in the Proceedings of the 21st Usenix Security Symposium, August 2012. (See https://factorable.net for more information and an extended version of the paper.)" Fix up trivial conflicts due to nearby changes in drivers/{mfd/ab3100-core.c, usb/gadget/omap_udc.c} * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: (33 commits) random: mix in architectural randomness in extract_buf() dmi: Feed DMI table to /dev/random driver random: Add comment to random_initialize() random: final removal of IRQF_SAMPLE_RANDOM um: remove IRQF_SAMPLE_RANDOM which is now a no-op sparc/ldc: remove IRQF_SAMPLE_RANDOM which is now a no-op [ARM] pxa: remove IRQF_SAMPLE_RANDOM which is now a no-op board-palmz71: remove IRQF_SAMPLE_RANDOM which is now a no-op isp1301_omap: remove IRQF_SAMPLE_RANDOM which is now a no-op pxa25x_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op omap_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op goku_udc: remove IRQF_SAMPLE_RANDOM which was commented out uartlite: remove IRQF_SAMPLE_RANDOM which is now a no-op drivers: hv: remove IRQF_SAMPLE_RANDOM which is now a no-op xen-blkfront: remove IRQF_SAMPLE_RANDOM which is now a no-op n2_crypto: remove IRQF_SAMPLE_RANDOM which is now a no-op pda_power: remove IRQF_SAMPLE_RANDOM which is now a no-op i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op input/serio/hp_sdc.c: remove IRQF_SAMPLE_RANDOM which is now a no-op mfd: remove IRQF_SAMPLE_RANDOM which is now a no-op ...
2012-07-19usb: Add quirk detection based on interface informationLaurent Pinchart1-3/+7
When a whole class of devices (possibly from a specific vendor, or across multiple vendors) require a quirk, explictly listing all devices in the class make the quirks table unnecessarily large. Fix this by allowing matching devices based on interface information. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16USB: notify phy when root hub port connect changeRichard Zhao1-0/+8
Phy may need to change settings when port connect change. Signed-off-by: Richard Zhao <richard.zhao@freescale.com> Tested-by: Subodh Nijsure <snijsure@grid-net.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16Merge tag 'for-usb-next-2012-07-11' of ↵Greg Kroah-Hartman1-17/+83
git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-next USB: Link PM fixes and Latency Tolerance Messaging Hi Greg, Here's four bug fix patches for Link PM (LPM), which are marked for 3.5-stable. There's also three patches that turn on Latency Tolerance Messaging (LTM) for xHCI host controllers and USB 3.0 devices that support this low power feature. Please queue for 3.6. Sarah Sharp
2012-07-16Merge 3.5-rc7 into usb-nextGreg Kroah-Hartman1-9/+12
This resolves the merge issue with the drivers/usb/host/ehci-omap.c file. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-14usb: feed USB device information to the /dev/random driverTheodore Ts'o1-0/+9
Send the USB device's serial, product, and manufacturer strings to the /dev/random driver to help seed its pools. Cc: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Greg KH <greg@kroah.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
2012-07-11USB: Add a sysfs file to show LTM capabilities.Sarah Sharp1-7/+0
USB 3.0 devices can optionally support Latency Tolerance Messaging (LTM). Add a new sysfs file in the device directory to show whether a device is LTM capable. This file will be present for both USB 2.0 and USB 3.0 devices. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-07-11USB: Enable Latency Tolerance Messaging (LTM).Sarah Sharp1-6/+81
USB 3.0 devices may optionally support a new feature called Latency Tolerance Messaging. If both the xHCI host controller and the device support LTM, it should be turned on in order to give the system hardware a better clue about the latency tolerance values of its PCI devices. Once a Set Feature request to enable LTM is received, the USB 3.0 device will begin to send LTM updates as its buffers fill or empty, and it can tolerate more or less latency. The USB 3.0 spec, section C.4.2 says that LTM should be disabled just before the device is placed into suspend. Then the device will send an updated LTM notification, so that the system doesn't think it should remain in an active state in order to satisfy the latency requirements of the suspended device. The Set and Clear Feature LTM enable command can only be sent to a configured device. The device will respond with an error if that command is sent while it is in the Default or Addressed state. Make sure to check udev->actconfig in usb_enable_ltm() and usb_disable_ltm(), and don't send those commands when the device is unconfigured. LTM should be enabled once a new configuration is installed in usb_set_configuration(). If we end up sending duplicate Set Feature LTM Enable commands on a switch from one installed configuration to another configuration, that should be harmless. Make sure that LTM is disabled before the device is unconfigured in usb_disable_device(). If no drivers are bound to the device, it doesn't make sense to allow the device to control the latency tolerance of the xHCI host controller. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-07-11USB: Fix LPM disable/enable during device reset.Sarah Sharp1-14/+12
The USB 3.0 specification says that sending a Set Feature or Clear Feature for U1/U2 Enable is not a valid request when the device is in the Default or Addressed state. It is only valid when the device is in the Configured state. The original LPM patch attempted to disable LPM after the device had been reset by hub_port_init(), before it had the configuration reinstalled. The TI hub I tested with did not fail the Clear Feature U1/U2 Enable request that khubd sent while it was in the addressed state, which is why I didn't catch it. Move the LPM disable before the device reset, so that we can send the Clear Feature U1/U2 Enable successfully, and balance the LPM disable count. Also delete any calls to usb_enable_lpm() on error paths that lead to re-enumeration. The calls will fail because the device isn't configured, and it's not useful to balance the LPM disable count because the usb_device is about to be destroyed before re-enumeration. Fix the early exit path ("done" label) to call usb_enable_lpm() to balance the LPM disable count. Note that calling usb_reset_and_verify_device() with an unconfigured device may fail on the first call to usb_disable_lpm(). That's because the LPM disable count is initialized to 0 (LPM enabled), and usb_disable_lpm() will attempt to send a Clear Feature U1/U2 request to a device in the Addressed state. The next patch will fix that. This commit should be backported to kernels as old as 3.5, that contain the commit 8306095fd2c1100e8244c09bf560f97aca5a311d "USB: Disable USB 3.0 LPM in critical sections." Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org
2012-07-06usb: convert port_owners type from void * to struct dev_state *Lan Tianyu1-9/+12
This patch is to convert port_owners type from void * to struct dev_state * in order to make code more readable. Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-02usb: Add support for root hub port status CASStanislaw Ledwon1-8/+10
The host controller port status register supports CAS (Cold Attach Status) bit. This bit could be set when USB3.0 device is connected when system is in Sx state. When the system wakes to S0 this port status with CAS bit is reported and this port can't be used by any device. When CAS bit is set the port should be reset by warm reset. This was not supported by xhci driver. The issue was found when pendrive was connected to suspended platform. The link state of "Compliance Mode" was reported together with CAS bit. This link state was also not supported by xhci and core/hub.c. The CAS bit is defined only for xhci root hub port and it is not supported on regular hubs. The link status is used to force warm reset on port. Make the USB core issue a warm reset when port is in ether the 'inactive' or 'compliance mode'. Change the xHCI driver to report 'compliance mode' when the CAS is set. This force warm reset on the root hub port. This patch should be backported to stable kernels as old as 3.2, that contain the commit 10d674a82e553cb8a1f41027bb3c3e309b3f6804 "USB: When hot reset for USB3 fails, try warm reset." Signed-off-by: Stanislaw Ledwon <staszek.ledwon@linux.intel.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Acked-by: Andiry Xu <andiry.xu@amd.com> Cc: stable@vger.kernel.org
2012-06-13USB: Checking the wrong variable in usb_disable_lpm()Dan Carpenter1-1/+1
We check "u1_params" instead of checking "u2_params". Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-05-21USB: Fix core compile with CONFIG_USB_SUSPEND=nSarah Sharp1-0/+4
When CONFIG_PM=n, make sure that the usb_[unlocked_][en/dis]able_lpm declarations are visible in include/linux/usb.h, and exported from drivers/usb/core/hub.c. Before this patch, if CONFIG_USB_SUSPEND was turned off, it would cause build errors: drivers/usb/core/hub.c: In function 'usb_disable_lpm': drivers/usb/core/hub.c:3394:2: error: implicit declaration of function 'usb_enable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/hub.c: At top level: drivers/usb/core/hub.c:3424:6: warning: conflicting types for 'usb_enable_lpm' [enabled by default] drivers/usb/core/hub.c:3394:2: note: previous implicit declaration of 'usb_enable_lpm' was here drivers/usb/core/driver.c: In function 'usb_probe_interface': drivers/usb/core/driver.c:339:2: error: implicit declaration of function 'usb_unlocked_disable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/driver.c:364:3: error: implicit declaration of function 'usb_unlocked_enable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/message.c: In function 'usb_set_interface': drivers/usb/core/message.c:1314:2: error: implicit declaration of function 'usb_disable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/message.c:1323:3: error: implicit declaration of function 'usb_enable_lpm' [-Werror=implicit-function-declaration] drivers/usb/core/message.c:1368:2: error: implicit declaration of function 'usb_unlocked_enable_lpm' [-Werror=implicit-function-declaration] Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: Chen Peter-B29397 <B29397@freescale.com>
2012-05-18USB: Disable USB 3.0 LPM in critical sections.Sarah Sharp1-0/+27
There are several places where the USB core needs to disable USB 3.0 Link PM: - usb_bind_interface - usb_unbind_interface - usb_driver_claim_interface - usb_port_suspend/usb_port_resume - usb_reset_and_verify_device - usb_set_interface - usb_reset_configuration - usb_set_configuration Use the new LPM disable/enable functions to temporarily disable LPM around these critical sections. We need to protect the critical section around binding and unbinding USB interface drivers. USB drivers may want to disable hub-initiated USB 3.0 LPM, which will change the value of the U1/U2 timeouts that the xHCI driver will install. We need to disable LPM completely until the driver is bound to the interface, and the driver has a chance to enable whatever alternate interface setting it needs in its probe routine. Then re-enable USB3 LPM, and recalculate the U1/U2 timeout values. We also need to disable LPM in usb_driver_claim_interface, because drivers like usbfs can bind to an interface through that function. Note, there is no way currently for userspace drivers to disable hub-initiated USB 3.0 LPM. Revisit this later. When a driver is unbound, the U1/U2 timeouts may change because we are unbinding the last driver that needed hub-initiated USB 3.0 LPM to be disabled. USB LPM must be disabled when a USB device is going to be suspended. The USB 3.0 spec does not define a state transition from U1 or U2 into U3, so we need to bring the device into U0 by disabling LPM before we can place it into U3. Therefore, call usb_unlocked_disable_lpm() in usb_port_suspend(), and call usb_unlocked_enable_lpm() in usb_port_resume(). If the port suspend fails, make sure to re-enable LPM by calling usb_unlocked_enable_lpm(), since usb_port_resume() will not be called on a failed port suspend. USB 3.0 devices lose their USB 3.0 LPM settings (including whether USB device-initiated LPM is enabled) across device suspend. Therefore, disable LPM before the device will be reset in usb_reset_and_verify_device(), and re-enable LPM after the reset is complete and the configuration/alt settings are re-installed. The calculated U1/U2 timeout values are heavily dependent on what USB device endpoints are currently enabled. When any of the enabled endpoints on the device might change, due to a new configuration, or new alternate interface setting, we need to first disable USB 3.0 LPM, add or delete endpoints from the xHCI schedule, install the new interfaces and alt settings, and then re-enable LPM. Do this in usb_set_interface, usb_reset_configuration, and usb_set_configuration. Basically, there is a call to disable and then enable LPM in all functions that lock the bandwidth_mutex. One exception is usb_disable_device, because the device is disconnecting or otherwise going away, and we should not care about whether USB 3.0 LPM is enabled. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-05-18USB: Add support to enable/disable USB3 link states.Sarah Sharp1-0/+414
There are various functions within the USB core that will need to disable USB 3.0 link power states. For example, when a USB device driver is being bound to an interface, we need to disable USB 3.0 LPM until we know if the driver will allow hub-initiated LPM transitions. Another example is when the USB core is switching alternate interface settings. The USB 3.0 timeout values are dependent on what endpoints are enabled, so we want to ensure that LPM is disabled until the new alt setting is fully installed. Multiple functions need to disable LPM, and those functions can even be nested. For example, usb_bind_interface() could disable LPM, and then call into the driver probe function, which may attempt to switch to a different alt setting. Therefore, we need to keep a count of the number of functions that require LPM to be disabled at any point in time. Introduce two new USB core API calls, usb_disable_lpm() and usb_enable_lpm(). These functions increment and decrement a new variable in the usb_device, lpm_disable_count. If usb_disable_lpm() fails, it will call usb_enable_lpm() in order to balance the lpm_disable_count. These two new functions must be called with the bandwidth_mutex locked. If the bandwidth_mutex is not already held by the caller, it should instead call usb_unlocked_disable_lpm() and usb_enable_lpm(), which take the bandwidth_mutex before calling usb_disable_lpm() and usb_enable_lpm(), respectively. Introduce a new variable (timeout) in the usb3_lpm_params structure to keep track of the currently enabled U1/U2 timeout values. When usb_disable_lpm() is called, and the USB device has the U1 or U2 timeouts set to a non-zero value (meaning either device-initiated or hub-initiated LPM is enabled), attempt to disable LPM, regardless of the state of the lpm_disable_count. We want to ensure that all callers can be guaranteed that LPM is disabled if usb_disable_lpm() returns zero. Otherwise the following scenario could occur: 1. Driver A is being bound to interface 1. usb_probe_interface() disables LPM. Driver A doesn't care if hub-initiated LPM is enabled, so even though usb_disable_lpm() fails, the probe of the driver continues, and the bandwidth mutex is dropped. 2. Meanwhile, Driver B is being bound to interface 2. usb_probe_interface() grabs the bandwidth mutex and calls usb_disable_lpm(). That call should attempt to disable LPM, even though the lpm_disable_count is set to 1 by Driver A. For usb_enable_lpm(), we attempt to enable LPM only when the lpm_disable_count is zero. If some step in enabling LPM fails, it will only have a minimal impact on power consumption, and all USB device drivers should still work properly. Therefore don't bother to return any error codes. Don't enable device-initiated LPM if the device is unconfigured. The USB device will only accept the U1/U2_ENABLE control transfers in the configured state. Do enable hub-initiated LPM in that case, since devices are allowed to accept the LGO_Ux link commands in any state. Don't enable or disable LPM if the device is marked as not being LPM capable. This can happen if: - the USB device doesn't have a SS BOS descriptor, - the device's parent hub has a zeroed bHeaderDecodeLatency value, or - the xHCI host doesn't support LPM. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Andiry Xu <andiry.xu@amd.com> Cc: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-05-18USB: Calculate USB 3.0 exit latencies for LPM.Sarah Sharp1-1/+210
There are several different exit latencies associated with coming out of the U1 or U2 lower power link state. Device Exit Latency (DEL) is the maximum time it takes for the USB device to bring its upstream link into U0. That can be found in the SuperSpeed Extended Capabilities BOS descriptor for the device. The time it takes for a particular link in the tree to exit to U0 is the maximum of either the parent hub's U1/U2 DEL, or the child's U1/U2 DEL. Hubs introduce a further delay that effects how long it takes a child device to transition to U0. When a USB 3.0 hub receives a header packet, it takes some time to decode that header and figure out which downstream port the packet was destined for. If the port is not in U0, this hub header decode latency will cause an additional delay for bringing the child device to U0. This Hub Header Decode Latency is found in the USB 3.0 hub descriptor. We can use DEL and the header decode latency, along with additional latencies imposed by each additional hub tier, to figure out the exit latencies for both host-initiated and device-initiated exit to U0. The Max Exit Latency (MEL) is the worst-case time it will take for a host-initiated exit to U0, based on whether U1 or U2 link states are enabled. The ping or packet must traverse the path to the device, and each hub along the way incurs the hub header decode latency in order to figure out which device the transfer was bound for. We say worst-case, because some hubs may not be in the lowest link state that is enabled. See the examples in section C.2.2.1. Note that "HSD" is a "host specific delay" that the power appendix architect has not been able to tell me how to calculate. There's no way to get HSD from the xHCI registers either, so I'm simply ignoring it. The Path Exit Latency (PEL) is the worst-case time it will take for a device-initiate exit to U0 to place all the links from the device to the host into U0. The System Exit Latency (SEL) is another device-initiated exit latency. SEL is useful for USB 3.0 devices that need to send data to the host at specific intervals. The device may send an NRDY to indicate it isn't ready to send data, then put its link into a lower power state. If it needs to have that data transmitted at a specific time, it can use SEL to back calculate when it will need to bring the link back into U0 to meet its deadlines. SEL is the worst-case time from the device-initiated exit to U0, to when the device will receive a packet from the host controller. It includes PEL, the time it takes for an ERDY to get to the host, a host-specific delay for the host to process that ERDY, and the time it takes for the packet to traverse the path to the device. See Figure C-2 in the USB 3.0 bus specification. Note: I have not been able to get good answers about what the host-specific delay to process the ERDY should be. The Intel HW developers say it will be specific to the platform the xHCI host is integrated into, and they say it's negligible. Ignore this too. Separate from these four exit latencies are the U1/U2 timeout values we program into the parent hubs. These timeouts tell the hub to attempt to place the device into a lower power link state after the link has been idle for that amount of time. Create two arrays (one for U1 and one for U2) to store mel, pel, sel, and the timeout values. Store the exit latency values in nanosecond units, since that's the smallest units used (DEL is in us, but the Hub Header Decode Latency is in ns). If a USB 3.0 device doesn't have a SuperSpeed Extended Capabilities BOS descriptor, it's highly unlikely it will be able to handle LPM requests properly. So it's best to disable LPM for devices that don't have this descriptor, and any children beneath it, if it's a USB 3.0 hub. Warn users when that happens, since it means they have a non-compliant USB 3.0 device or hub. This patch assumes a simplified design where links deep in the tree will not have U1 or U2 enabled unless all their parent links have the corresponding LPM state enabled. Eventually, we might want to allow a different policy, and we can revisit this patch when that happens. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: Alan Stern <stern@rowland.harvard.edu>
2012-05-18USB: Refactor code to set LPM support flag.Sarah Sharp1-5/+17
Refactor the code that sets the usb_device flag to indicate the device support link power management (lpm_capable). The current code sets lpm_capable unconditionally if the USB devices have a USB 2.0 Extended Capabilities Descriptor. USB 3.0 devices can also have that descriptor, but the xHCI driver code that uses lpm_capable will not run the USB 2.0 LPM test for devices under the USB 3.0 roothub. Therefore, it's fine only set lpm_capable for high speed devices in this refactoring. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
2012-05-17usbcore: enable USB2 LPM if port suspend failsAndiry Xu1-0/+4
USB2 LPM is disabled when device begin to suspend and enabled after device is resumed. That's because USB spec does not define the transition from U1/U2 state to U3 state. If usb_port_suspend() fails, usb_port_resume() is never called, and USB2 LPM is disabled in this situation. Enable USB2 LPM if port suspend fails. This patch should be backported to kernels as old as 3.2, that contain the commit 65580b4321eb36f16ae8b5987bfa1bb948fc5112 "xHCI: set USB2 hardware LPM". Signed-off-by: Andiry Xu <andiry.xu@gmail.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org
2012-05-14Revert "usb: add struct usb_hub_port to store port related members."Greg Kroah-Hartman1-16/+13
This reverts commit f397d7c4c5e8a1eb93f2ed15808a509318ccf1dd. This series isn't quite ready for 3.5 just yet, so revert it and give the author more time to get it correct. Cc: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-14Revert "usb: move struct usb_device->children to struct usb_hub_port->child"Greg Kroah-Hartman1-40/+27
This reverts commit bebc56d58dc780539777d2b1ca80df5566e2ad87. The call here is fragile and not well thought out, so revert it, it's not fully baked yet and I don't want this to go into 3.5. Cc: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-11usb: move struct usb_device->children to struct usb_hub_port->childLan Tianyu1-27/+40
Move child's pointer to the struct usb_hub_port since the child device is directly associated with the port. Provide usb_get_hub_child_device() to get child's pointer. Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>