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Using a period after a newline causes bad output.
Miscellanea:
o Coalesce formats too
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Sometimes the USB device gets confused about the state of the initialization and
the connection fails. In particular, the device thinks that it's already set up
and running while the host thinks the device still needs to be configured. To
work around this issue, power-cycle the hub's output to issue a sort of "reset"
to the device. This makes the device restart its state machine and then the
initialization succeeds.
This fixes problems where the kernel reports a list of errors like this:
usb 1-1.3: device not accepting address 19, error -71
The end result is a non-functioning device. After this patch, the sequence
becomes like this:
usb 1-1.3: new high-speed USB device number 18 using ci_hdrc
usb 1-1.3: device not accepting address 18, error -71
usb 1-1.3: new high-speed USB device number 19 using ci_hdrc
usb 1-1.3: device not accepting address 19, error -71
usb 1-1-port3: attempt power cycle
usb 1-1.3: new high-speed USB device number 21 using ci_hdrc
usb-storage 1-1.3:1.2: USB Mass Storage device detected
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This new helper is a simple wrapper around usb_get_status(). This
patch is in preparation to adding support for fetching PTM_STATUS
types. No functional changes.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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To match the rest of the kernel, the SPDX tags for the drivers/usb/core/
files are moved to the first line of the file. This makes it more
obvious the tag is present as well as making it match the other 12k
files in the tree with this location.
It also uses // to match the "expected style" as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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We need the USB fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When going into S3 suspend, the Acer TravelMate P648-M and P648-G3
laptops immediately wake up 3-4 seconds later for no obvious reason.
Unbinding the integrated Huawei 4G LTE modem before suspend avoids
the issue, even though we are not using the modem at all (checked
from rescue.target/runlevel1). The problem also occurs when the option
and cdc-ether modem drivers aren't loaded; it reproduces just with the
base usb driver. Under Windows the system can suspend fine.
Seeking a better fix, we've tried a lot of things, including:
- Check that the device's power/wakeup is disabled
- Check that remote wakeup is off at the USB level
- All the quirks in drivers/usb/core/quirks.c e.g. USB_QUIRK_RESET_RESUME,
USB_QUIRK_RESET, USB_QUIRK_IGNORE_REMOTE_WAKEUP, USB_QUIRK_NO_LPM.
but none of that makes any difference.
There are no errors in the logs showing any suspend/resume-related issues.
When the system wakes up due to the modem, log-wise it appears to be a
normal resume.
Introduce a quirk to disable the port during suspend when the modem is
detected.
The modem from the P648-G3 model is:
T: Bus=01 Lev=01 Prnt=01 Port=08 Cnt=04 Dev#= 5 Spd=480 MxCh= 0
D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=ff MxPS=64 #Cfgs= 3
P: Vendor=12d1 ProdID=15c3 Rev= 1.02
S: Manufacturer=Huawei Technologies Co., Ltd.
S: Product=HUAWEI Mobile
S: SerialNumber=0123456789ABCDEF
C: #Ifs= 5 Cfg#= 1 Atr=a0 MxPwr= 2mA
I: If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=06 Prot=10 Driver=
E: Ad=82(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I: If#= 1 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=13 Driver=
E: Ad=83(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I: If#= 2 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=12 Driver=
E: Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I: If#= 3 Alt= 0 #EPs= 1 Cls=ff(vend.) Sub=06 Prot=16 Driver=
E: Ad=86(I) Atr=03(Int.) MxPS= 16 Ivl=2ms
I: If#= 3 Alt= 1 #EPs= 3 Cls=ff(vend.) Sub=06 Prot=16 Driver=
E: Ad=86(I) Atr=03(Int.) MxPS= 16 Ivl=2ms
E: Ad=85(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I: If#= 4 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=1b Driver=
E: Ad=87(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
C:* #Ifs= 6 Cfg#= 2 Atr=a0 MxPwr= 2mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=06 Prot=00 Driver=cdc_ether
E: Ad=82(I) Atr=03(Int.) MxPS= 16 Ivl=2ms
I:* If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=06 Prot=00 Driver=cdc_ether
E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=06 Prot=10 Driver=option
E: Ad=84(I) Atr=03(Int.) MxPS= 10 Ivl=32ms
E: Ad=83(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 3 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=13 Driver=option
E: Ad=85(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 4 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=12 Driver=option
E: Ad=86(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 5 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=06 Prot=1b Driver=option
E: Ad=87(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
C: #Ifs= 2 Cfg#= 3 Atr=a0 MxPwr= 2mA
A: FirstIf#= 0 IfCount= 2 Cls=02(comm.) Sub=0e Prot=00
I: If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=0e Prot=00 Driver=
E: Ad=82(I) Atr=03(Int.) MxPS= 16 Ivl=2ms
I: If#= 1 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=02 Driver=
I: If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=02 Driver=
E: Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E: Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
Based on an earlier patch by Chris Chiu.
Signed-off-by: Daniel Drake <drake@endlessm.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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If the connect status change is set during reset signaling, but
the status remains connected just retry port reset.
This solves an issue with connecting a 90W HP Thunderbolt 3 dock
with a Lenovo Carbon x1 (5th generation) which causes a 30min loop
of a high speed device being re-discovererd before usb ports starts
working.
[...]
[ 389.023845] usb 3-1: new high-speed USB device number 55 using xhci_hcd
[ 389.491841] usb 3-1: new high-speed USB device number 56 using xhci_hcd
[ 389.959928] usb 3-1: new high-speed USB device number 57 using xhci_hcd
[...]
This is caused by a high speed device that doesn't successfully go to the
enabled state after the second port reset. Instead the connection bounces
(connected, with connect status change), bailing out completely from
enumeration just to restart from scratch.
Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1716332
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Commit e0429362ab15
("usb: Add device quirk for Logitech HD Pro Webcams C920 and C930e")
introduced quirk to workaround an issue with some Logitech webcams.
The workaround is introducing delay for some USB operations.
According to our testing, delay introduced by original commit
is not long enough and in rare cases we still see issues described
by the aforementioned commit.
This patch increases delays introduced by original commit.
Having this patch applied we do not see those problems anymore.
Signed-off-by: Dmitry Fleytman <dmitry@daynix.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Save 80ms device enumeration time by increasing root hub port reset time
The 50ms reset signaling time is not enough for most root hub ports.
Increasing the reset time to 60ms allows host controllers to finish port
reset and removes a retry causing an extra 50ms delay.
The USB 2 specification requires "at least 50ms" for driving root
port reset. The current msleep is exactly 50ms which may not be
enough if there are any delays between writing the reset bit to host
controller portsc register and phy actually driving reset.
On Haswell, Skylake and Kabylake xHC port reset took in average 52-59ms
The 80ms improvement comes from (40ms * 2 port resets) save at enumeration
for each device connected to a root hub port.
more details about root port reset in USB2 section 7.1.7.5:.
"Software must ensure that resets issued to the root ports drive reset
long enough to overwhelm any concurrent resume attempts by downstream
devices. It is required that resets from root ports have a duration of
at least 50 ms (TDRSTR).
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This gets the USB fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Some buggy USB disk adapters disconnect and reconnect multiple times
during the enumeration procedure. This may lead to a device
connecting at full speed instead of high speed, because when the USB
stack sees that a device isn't able to enumerate at high speed, it
tries to hand the connection over to a full-speed companion
controller.
The logic for doing this is careful to check that the device is still
connected. But this check is inadequate if the device disconnects and
reconnects before the check is done. The symptom is that a device
works, but much more slowly than it is capable of operating.
The situation was made worse recently by commit 22547c4cc4fe ("usb:
hub: Wait for connection to be reestablished after port reset"), which
increases the delay following a reset before a disconnect is
recognized, thus giving the device more time to reconnect.
This patch makes the check more robust. If the device was
disconnected at any time during enumeration, we will now skip the
full-speed handover.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: Zdenek Kabelac <zkabelac@redhat.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The controller driver may be NULL if the controller device
is the middle device between platform device and roothub.
This middle device may not need a device driver due to all
hardware control can be at platform device driver, this
platform device is usually a dual-role USB controller device.
The benefit of using this middle device is we can keep both
controller device's private data (known as struct usb_hcd)
for USB core use, and platform device's private data for
platform driver use.
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Rework smelling code (goto inside compound statement). Perhaps this is
legacy. Anyway such code is not appropriate for Linux kernel.
Signed-off-by: Eugene Korenevsky <ekorenevsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The original motivation for disabling/enabling Link PM at device
suspend/resume was to force link state to go via U0 before suspend sets
the link state to U3. Going directly from U2 to U3 is not allowed.
Disabling LPM will forced the link state to U0, but will send a lot of
Set port feature requests for evert suspend and resume.
This is not needed as Hub hardware will take care of going via U0
when a U2 -> U3 transition is requested [1]
[1] USB 3.1 specification section 10.16.2.10 Set Port Feature:
"If the value is 3, then host software wants to selectively suspend the
device connected to this port. The hub shall transition the link to U3
from any of the other U states using allowed link state transitions.
If the port is not already in the U0 state, then it shall transition the
port to the U0 state and then initiate the transition to U3.
While this state is active, the hub does not propagate downstream-directed
traffic to this port, but the hub will respond to resume signaling from the
port"
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add define for the maximum number of ports on a SuperSpeed hub as per
USB 3.1 spec Table 10-5, and use it when verifying the retrieved hub
descriptor.
This specifically avoids benign attempts to update the DeviceRemovable
mask for non-existing ports (should we get that far).
Fixes: dbe79bbe9dcb ("USB 3.0 Hub Changes")
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add missing sanity check on the non-SuperSpeed hub-descriptor length in
order to avoid parsing and leaking two bytes of uninitialised slab data
through sysfs removable-attributes (or a compound-device debug
statement).
Note that we only make sure that the DeviceRemovable field is always
present (and specifically ignore the unused PortPwrCtrlMask field) in
order to continue support any hubs with non-compliant descriptors. As a
further safeguard, the descriptor buffer is also cleared.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org> # 2.6.12
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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A SuperSpeed hub descriptor does not have any variable-length fields so
bail out when reading a short descriptor.
This avoids parsing and leaking two bytes of uninitialised slab data
through sysfs removable-attributes.
Fixes: dbe79bbe9dcb ("USB 3.0 Hub Changes")
Cc: stable <stable@vger.kernel.org> # 2.6.39
Cc: John Youn <John.Youn@synopsys.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This resolves a merge issue in the gadget code, and we want the USB
fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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While running a bind/unbind stress test with the dwc3 usb driver on rk3399,
the following crash was observed.
Unable to handle kernel NULL pointer dereference at virtual address 00000218
pgd = ffffffc00165f000
[00000218] *pgd=000000000174f003, *pud=000000000174f003,
*pmd=0000000001750003, *pte=00e8000001751713
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in: uinput uvcvideo videobuf2_vmalloc cmac
ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat rfcomm
xt_mark fuse bridge stp llc zram btusb btrtl btbcm btintel bluetooth
ip6table_filter mwifiex_pcie mwifiex cfg80211 cdc_ether usbnet r8152 mii joydev
snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device ppp_async
ppp_generic slhc tun
CPU: 1 PID: 29814 Comm: kworker/1:1 Not tainted 4.4.52 #507
Hardware name: Google Kevin (DT)
Workqueue: pm pm_runtime_work
task: ffffffc0ac540000 ti: ffffffc0af4d4000 task.ti: ffffffc0af4d4000
PC is at autosuspend_check+0x74/0x174
LR is at autosuspend_check+0x70/0x174
...
Call trace:
[<ffffffc00080dcc0>] autosuspend_check+0x74/0x174
[<ffffffc000810500>] usb_runtime_idle+0x20/0x40
[<ffffffc000785ae0>] __rpm_callback+0x48/0x7c
[<ffffffc000786af0>] rpm_idle+0x1e8/0x498
[<ffffffc000787cdc>] pm_runtime_work+0x88/0xcc
[<ffffffc000249bb8>] process_one_work+0x390/0x6b8
[<ffffffc00024abcc>] worker_thread+0x480/0x610
[<ffffffc000251a80>] kthread+0x164/0x178
[<ffffffc0002045d0>] ret_from_fork+0x10/0x40
Source:
(gdb) l *0xffffffc00080dcc0
0xffffffc00080dcc0 is in autosuspend_check
(drivers/usb/core/driver.c:1778).
1773 /* We don't need to check interfaces that are
1774 * disabled for runtime PM. Either they are unbound
1775 * or else their drivers don't support autosuspend
1776 * and so they are permanently active.
1777 */
1778 if (intf->dev.power.disable_depth)
1779 continue;
1780 if (atomic_read(&intf->dev.power.usage_count) > 0)
1781 return -EBUSY;
1782 w |= intf->needs_remote_wakeup;
Code analysis shows that intf is set to NULL in usb_disable_device() prior
to setting actconfig to NULL. At the same time, usb_runtime_idle() does not
lock the usb device, and neither does any of the functions in the
traceback. This means that there is no protection against a race condition
where usb_disable_device() is removing dev->actconfig->interface[] pointers
while those are being accessed from autosuspend_check().
To solve the problem, synchronize and validate device state between
autosuspend_check() and usb_disconnect().
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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While stress testing a usb controller using a bind/unbind looop, the
following error loop was observed.
usb 7-1.2: new low-speed USB device number 3 using xhci-hcd
usb 7-1.2: hub failed to enable device, error -108
usb 7-1-port2: cannot disable (err = -22)
usb 7-1-port2: couldn't allocate usb_device
usb 7-1-port2: cannot disable (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: activate --> -22
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
hub 7-1:1.0: hub_ext_port_status failed (err = -22)
** 57 printk messages dropped ** hub 7-1:1.0: activate --> -22
** 82 printk messages dropped ** hub 7-1:1.0: hub_ext_port_status failed (err = -22)
This continues forever. After adding tracebacks into the code,
the call sequence leading to this is found to be as follows.
[<ffffffc0007fc8e0>] hub_activate+0x368/0x7b8
[<ffffffc0007fceb4>] hub_resume+0x2c/0x3c
[<ffffffc00080b3b8>] usb_resume_interface.isra.6+0x128/0x158
[<ffffffc00080b5d0>] usb_suspend_both+0x1e8/0x288
[<ffffffc00080c9c4>] usb_runtime_suspend+0x3c/0x98
[<ffffffc0007820a0>] __rpm_callback+0x48/0x7c
[<ffffffc00078217c>] rpm_callback+0xa8/0xd4
[<ffffffc000786234>] rpm_suspend+0x84/0x758
[<ffffffc000786ca4>] rpm_idle+0x2c8/0x498
[<ffffffc000786ed4>] __pm_runtime_idle+0x60/0xac
[<ffffffc00080eba8>] usb_autopm_put_interface+0x6c/0x7c
[<ffffffc000803798>] hub_event+0x10ac/0x12ac
[<ffffffc000249bb8>] process_one_work+0x390/0x6b8
[<ffffffc00024abcc>] worker_thread+0x480/0x610
[<ffffffc000251a80>] kthread+0x164/0x178
[<ffffffc0002045d0>] ret_from_fork+0x10/0x40
kick_hub_wq() is called from hub_activate() even after failures to
communicate with the hub. This results in an endless sequence of
hub event -> hub activate -> wq trigger -> hub event -> ...
Provide two solutions for the problem.
- Only trigger the hub event queue if communication with the hub
is successful.
- After a suspend failure, only resume already suspended interfaces
if the communication with the device is still possible.
Each of the changes fixes the observed problem. Use both to improve
robustness.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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If usb_get_bos_descriptor() returns an error, usb->bos will be NULL.
Nevertheless, it is dereferenced unconditionally in
hub_set_initial_usb2_lpm_policy() if usb2_hw_lpm_capable is set.
This results in a crash.
usb 5-1: unable to get BOS descriptor
...
Unable to handle kernel NULL pointer dereference at virtual address 00000008
pgd = ffffffc00165f000
[00000008] *pgd=000000000174f003, *pud=000000000174f003,
*pmd=0000000001750003, *pte=00e8000001751713
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in: uinput uvcvideo videobuf2_vmalloc cmac [ ... ]
CPU: 5 PID: 3353 Comm: kworker/5:3 Tainted: G B 4.4.52 #480
Hardware name: Google Kevin (DT)
Workqueue: events driver_set_config_work
task: ffffffc0c3690000 ti: ffffffc0ae9a8000 task.ti: ffffffc0ae9a8000
PC is at hub_port_init+0xc3c/0xd10
LR is at hub_port_init+0xc3c/0xd10
...
Call trace:
[<ffffffc0007fbbfc>] hub_port_init+0xc3c/0xd10
[<ffffffc0007fbe2c>] usb_reset_and_verify_device+0x15c/0x82c
[<ffffffc0007fc5e0>] usb_reset_device+0xe4/0x298
[<ffffffbffc0e3fcc>] rtl8152_probe+0x84/0x9b0 [r8152]
[<ffffffc00080ca8c>] usb_probe_interface+0x244/0x2f8
[<ffffffc000774a24>] driver_probe_device+0x180/0x3b4
[<ffffffc000774e48>] __device_attach_driver+0xb4/0xe0
[<ffffffc000772168>] bus_for_each_drv+0xb4/0xe4
[<ffffffc0007747ec>] __device_attach+0xd0/0x158
[<ffffffc000775080>] device_initial_probe+0x24/0x30
[<ffffffc0007739d4>] bus_probe_device+0x50/0xe4
[<ffffffc000770bd0>] device_add+0x414/0x738
[<ffffffc000809fe8>] usb_set_configuration+0x89c/0x914
[<ffffffc00080a120>] driver_set_config_work+0xc0/0xf0
[<ffffffc000249bb8>] process_one_work+0x390/0x6b8
[<ffffffc00024abcc>] worker_thread+0x480/0x610
[<ffffffc000251a80>] kthread+0x164/0x178
[<ffffffc0002045d0>] ret_from_fork+0x10/0x40
Since we don't know anything about LPM capabilities without BOS descriptor,
don't attempt to enable LPM if it is not available.
Fixes: 890dae886721 ("xhci: Enable LPM support only for hardwired ...")
Cc: stable <stable@vger.kernel.org>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Update the .c files that depend on these APIs.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
If CONFIG_PM=n:
drivers/usb/core/hub.c:107: warning: ‘hub_usb3_port_prepare_disable’ declared inline after being called
drivers/usb/core/hub.c:107: warning: previous declaration of ‘hub_usb3_port_prepare_disable’ was here
To fix this, move hub_port_disable() after
hub_usb3_port_prepare_disable(), and adjust forward declarations.
Fixes: 37be66767e3cae4f ("usb: hub: Fix auto-remount of safely removed or ejected USB-3 devices")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
On a system with a defective USB device connected to an USB hub,
an endless sequence of port connect events was observed. The sequence
of events as observed is as follows:
- Port reports connected event (port status=USB_PORT_STAT_CONNECTION).
- Event handler debounces port and resets it by calling hub_port_reset().
- hub_port_reset() calls hub_port_wait_reset() to wait for the reset
to complete.
- The reset completes, but USB_PORT_STAT_CONNECTION is not immediately
set in the port status register.
- hub_port_wait_reset() returns -ENOTCONN.
- Port initialization sequence is aborted.
- A few milliseconds later, the port again reports a connected event,
and the sequence repeats.
This continues either forever or, randomly, stops if the connection
is already re-established when the port status is read. It results in
a high rate of udev events. This in turn destabilizes userspace since
the above sequence holds the device mutex pretty much continuously
and prevents userspace from actually reading the device status.
To prevent the problem from happening, let's wait for the connection
to be re-established after a port reset. If the device was actually
disconnected, the code will still return an error, but it will do so
only after the long reset timeout.
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
USB-3 does not have any link state that will avoid negotiating a connection
with a plugged-in cable but will signal the host when the cable is
unplugged.
For USB-3 we used to first set the link to Disabled, then to RxDdetect to
be able to detect cable connects or disconnects. But in RxDetect the
connected device is detected again and eventually enabled.
Instead set the link into U3 and disable remote wakeups for the device.
This is what Windows does, and what Alan Stern suggested.
Cc: stable@vger.kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Some of the USB core files were missing explicit license information.
As all files in the kernel tree are implicitly licensed under the
GPLv2-only, be explicit in case someone get confused looking at
individual files by using the SPDX nomenclature.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
In USB20 specification, describes in chapter 9.4.5: The Remote Wakeup
field can be modified by the SetFeature() and ClearFeature() requests
using the DEVICE_REMOTE_WAKEUP feature selector.
In USB30 specification, also describes in chapter 9.4.5: The Function
Remote Wakeup field can be modified by the SetFeature() requests
using the FUNCTION_SUSPEND feature selector. In chapter 9.4.9 Set
Feature reference, it describes Function Remote Wake Enabled/Disabled
at suspend options by SET_FEATURE.
In USB30 specification only mentioned SetFeature(), so we need use
SET_FEATURE replace CLEAR_FEATURE to disable USB30 function remote
wakeup in suspend options.
Signed-off-by: Yonglong Wu <yonglong.wu@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
All kmalloc-based functions print enough information on failures.
Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
The locking in hub_activate() is not adequate to provide full mutual
exclusion with hub_quiesce(). The subroutine locks the hub's
usb_interface, but the callers of hub_quiesce() (such as
hub_pre_reset() and hub_event()) hold the lock to the hub's
usb_device.
This patch changes hub_activate() to make it acquire the same lock as
those other routines.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org> #4.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
The early-exit pathway in hub_activate, added by commit e50293ef9775
("USB: fix invalid memory access in hub_activate()") needs
improvement. It duplicates code that is already present at the end of
the subroutine, and it neglects to undo the effect of a
usb_autopm_get_interface_no_resume() call.
This patch fixes both problems by making the early-exit pathway jump
directly to the end of the subroutine. It simplifies the code at the
end by merging two conditionals that actually test the same condition
although they appear different: If type < HUB_INIT3 then type must be
either HUB_INIT2 or HUB_INIT, and it can't be HUB_INIT because in that
case the subroutine would have exited earlier.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org> #4.4+
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Memory leak and unbalanced reference count:
If the hub gets disconnected while the core is still activating it, this
can result in leaking memory of few USB structures.
This will happen if we have done a kref_get() from hub_activate() and
scheduled a delayed work item for HUB_INIT2/3. Now if hub_disconnect()
gets called before the delayed work expires, then we will cancel the
work from hub_quiesce(), but wouldn't do a kref_put(). And so the
unbalance.
kmemleak reports this as (with the commit e50293ef9775 backported to
3.10 kernel with other changes, though the same is true for mainline as
well):
unreferenced object 0xffffffc08af5b800 (size 1024):
comm "khubd", pid 73, jiffies 4295051211 (age 6482.350s)
hex dump (first 32 bytes):
30 68 f3 8c c0 ff ff ff 00 a0 b2 2e c0 ff ff ff 0h..............
01 00 00 00 00 00 00 00 00 94 7d 40 c0 ff ff ff ..........}@....
backtrace:
[<ffffffc0003079ec>] create_object+0x148/0x2a0
[<ffffffc000cc150c>] kmemleak_alloc+0x80/0xbc
[<ffffffc000303a7c>] kmem_cache_alloc_trace+0x120/0x1ac
[<ffffffc0006fa610>] hub_probe+0x120/0xb84
[<ffffffc000702b20>] usb_probe_interface+0x1ec/0x298
[<ffffffc0005d50cc>] driver_probe_device+0x160/0x374
[<ffffffc0005d5308>] __device_attach+0x28/0x4c
[<ffffffc0005d3164>] bus_for_each_drv+0x78/0xac
[<ffffffc0005d4ee0>] device_attach+0x6c/0x9c
[<ffffffc0005d42b8>] bus_probe_device+0x28/0xa0
[<ffffffc0005d23a4>] device_add+0x324/0x604
[<ffffffc000700fcc>] usb_set_configuration+0x660/0x6cc
[<ffffffc00070a350>] generic_probe+0x44/0x84
[<ffffffc000702914>] usb_probe_device+0x54/0x74
[<ffffffc0005d50cc>] driver_probe_device+0x160/0x374
[<ffffffc0005d5308>] __device_attach+0x28/0x4c
Deadlocks:
If the hub gets disconnected early enough (i.e. before INIT2/INIT3 are
finished and the init_work is still queued), the core may call
hub_quiesce() after acquiring interface device locks and it will wait
for the work to be cancelled synchronously. But if the work handler is
already running in parallel, it may try to acquire the same interface
device lock and this may result in deadlock.
Fix both the issues by removing the call to cancel_delayed_work_sync().
CC: <stable@vger.kernel.org> #4.4+
Fixes: e50293ef9775 ("USB: fix invalid memory access in hub_activate()")
Reported-by: Manu Gautam <mgautam@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
The XHCI controller presents two USB buses to the system - one for USB2
and one for USB3. The hub init code (hub_port_init) is reentrant but
only locks one bus per thread, leading to a race condition failure when
two threads attempt to simultaneously initialise a USB2 and USB3 device:
[ 8.034843] xhci_hcd 0000:00:14.0: Timeout while waiting for setup device command
[ 13.183701] usb 3-3: device descriptor read/all, error -110
On a test system this failure occurred on 6% of all boots.
The call traces at the point of failure are:
Call Trace:
[<ffffffff81b9bab7>] schedule+0x37/0x90
[<ffffffff817da7cd>] usb_kill_urb+0x8d/0xd0
[<ffffffff8111e5e0>] ? wake_up_atomic_t+0x30/0x30
[<ffffffff817dafbe>] usb_start_wait_urb+0xbe/0x150
[<ffffffff817db10c>] usb_control_msg+0xbc/0xf0
[<ffffffff817d07de>] hub_port_init+0x51e/0xb70
[<ffffffff817d4697>] hub_event+0x817/0x1570
[<ffffffff810f3e6f>] process_one_work+0x1ff/0x620
[<ffffffff810f3dcf>] ? process_one_work+0x15f/0x620
[<ffffffff810f4684>] worker_thread+0x64/0x4b0
[<ffffffff810f4620>] ? rescuer_thread+0x390/0x390
[<ffffffff810fa7f5>] kthread+0x105/0x120
[<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200
[<ffffffff81ba183f>] ret_from_fork+0x3f/0x70
[<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200
Call Trace:
[<ffffffff817fd36d>] xhci_setup_device+0x53d/0xa40
[<ffffffff817fd87e>] xhci_address_device+0xe/0x10
[<ffffffff817d047f>] hub_port_init+0x1bf/0xb70
[<ffffffff811247ed>] ? trace_hardirqs_on+0xd/0x10
[<ffffffff817d4697>] hub_event+0x817/0x1570
[<ffffffff810f3e6f>] process_one_work+0x1ff/0x620
[<ffffffff810f3dcf>] ? process_one_work+0x15f/0x620
[<ffffffff810f4684>] worker_thread+0x64/0x4b0
[<ffffffff810f4620>] ? rescuer_thread+0x390/0x390
[<ffffffff810fa7f5>] kthread+0x105/0x120
[<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200
[<ffffffff81ba183f>] ret_from_fork+0x3f/0x70
[<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200
Which results from the two call chains:
hub_port_init
usb_get_device_descriptor
usb_get_descriptor
usb_control_msg
usb_internal_control_msg
usb_start_wait_urb
usb_submit_urb / wait_for_completion_timeout / usb_kill_urb
hub_port_init
hub_set_address
xhci_address_device
xhci_setup_device
Mathias Nyman explains the current behaviour violates the XHCI spec:
hub_port_reset() will end up moving the corresponding xhci device slot
to default state.
As hub_port_reset() is called several times in hub_port_init() it
sounds reasonable that we could end up with two threads having their
xhci device slots in default state at the same time, which according to
xhci 4.5.3 specs still is a big no no:
"Note: Software shall not transition more than one Device Slot to the
Default State at a time"
So both threads fail at their next task after this.
One fails to read the descriptor, and the other fails addressing the
device.
Fix this in hub_port_init by locking the USB controller (instead of an
individual bus) to prevent simultaneous initialisation of both buses.
Fixes: 638139eb95d2 ("usb: hub: allow to process more usb hub events in parallel")
Link: https://lkml.org/lkml/2016/2/8/312
Link: https://lkml.org/lkml/2016/2/4/748
Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
If a port can do 10 Gb/s the kernel should say so.
The corresponding check needs to be added.
Signed-off.by: Oliver Neukum <ONeukum@suse.com>>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
A typo of j for i led to a logic bug. To rule out future
confusion, the variable names are made meaningful.
Signed-off-by: Oliver Neukum <ONeukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
We want the USB fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
This reverts commit d8f00cd685f5c8e0def8593e520a7fef12c22407.
Tony writes:
This upstream commit is causing an oops:
d8f00cd685f5 ("usb: hub: do not clear BOS field during reset device")
This patch has already been included in several -stable kernels. Here
are the affected kernels:
4.5.0-rc4 (current git)
4.4.2
4.3.6 (currently in review)
4.1.18
3.18.27
3.14.61
How to reproduce the problem:
Boot kernel with slub debugging enabled (otherwise memory corruption
will cause random oopses later instead of immediately)
Plug in USB 3.0 disk to xhci USB 3.0 port
dd if=/dev/sdc of=/dev/null bs=65536
(where /dev/sdc is the USB 3.0 disk)
Unplug USB cable while dd is still going
Oops is immediate:
Reported-by: Tony Battersby <tonyb@cybernetics.com>
Cc: Du, Changbin <changbin.du@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Some devices I got show an inability to operate right after
power on if they are already connected. They are beyond recovery
if the descriptors are requested multiple times. So in case of
a timeout we rather bail early and reset again. But it must be
done only on the first loop lest we get into a reset/time out
spiral that can be overcome with a retry.
This patch is a rework of a patch that fell through the cracks.
http://www.spinics.net/lists/linux-usb/msg103263.html
Signed-off-by: Oliver Neukum <oneukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
fixing the error reported by script checkpatch.pl
static variables blinkenlights and old_scheme_first
were initialised to 0, correcting it.
Signed-off-by: Saurabh Sengar <saurabh.truth@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Now that usb_bus_list has been removed and switched to idr
rename the related mutex accordingly.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
We want the USB fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
In function usb_reset_and_verify_device, the old BOS descriptor may
still be used before allocating a new one. (usb_unlocked_disable_lpm
function uses it under the situation that it fails to disable lpm.)
So we cannot set the udev->bos to NULL before that, just keep what it
was. It will be overwrite when allocating a new one.
Crash log:
BUG: unable to handle kernel NULL pointer dereference at
0000000000000010
IP: [<ffffffff8171f98d>] usb_enable_link_state+0x2d/0x2f0
Call Trace:
[<ffffffff8171ed5b>] ? usb_set_lpm_timeout+0x12b/0x140
[<ffffffff8171fcd1>] usb_enable_lpm+0x81/0xa0
[<ffffffff8171fdd8>] usb_disable_lpm+0xa8/0xc0
[<ffffffff8171fe1c>] usb_unlocked_disable_lpm+0x2c/0x50
[<ffffffff81723933>] usb_reset_and_verify_device+0xc3/0x710
[<ffffffff8172c4ed>] ? usb_sg_wait+0x13d/0x190
[<ffffffff81724743>] usb_reset_device+0x133/0x280
[<ffffffff8179ccd1>] usb_stor_port_reset+0x61/0x70
[<ffffffff8179cd68>] usb_stor_invoke_transport+0x88/0x520
Signed-off-by: Du, Changbin <changbin.du@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Use bus_to_hcd() instead of open-coding it.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
usb 3.1 extend the hub get-port-status request by adding different
request types. the new request types return 4 additional bytes called
extended port status, these bytes are returned after the regular
portstatus and portchange values.
The extended port status contains a speed ID for the currently used
sublink speed. A table of supported Speed IDs with details about the link
is provided by the hub in the device descriptor BOS SuperSpeedPlus
device capability Sublink Speed Attributes.
Support this new request. Ask for the extended port status after port
reset if hub supports USB 3.1. If link is running at SuperSpeedPlus
set the device speed to USB_SPEED_SUPER_PLUS
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Add a new USB_SPEED_SUPER_PLUS device speed, and make sure usb core can
handle the new speed.
In most cases the behaviour is the same as with USB_SPEED_SUPER SuperSpeed
devices. In a few places we add a "Plus" string to inform the user of the
new speed.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
We want the USB and PHY fixes in here as well to make things easier for
testing and development.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Commit 8520f38099cc ("USB: change hub initialization sleeps to
delayed_work") changed the hub_activate() routine to make part of it
run in a workqueue. However, the commit failed to take a reference to
the usb_hub structure or to lock the hub interface while doing so. As
a result, if a hub is plugged in and quickly unplugged before the work
routine can run, the routine will try to access memory that has been
deallocated. Or, if the hub is unplugged while the routine is
running, the memory may be deallocated while it is in active use.
This patch fixes the problem by taking a reference to the usb_hub at
the start of hub_activate() and releasing it at the end (when the work
is finished), and by locking the hub interface while the work routine
is running. It also adds a check at the start of the routine to see
if the hub has already been disconnected, in which nothing should be
done.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Alexandru Cornea <alexandru.cornea@intel.com>
Tested-by: Alexandru Cornea <alexandru.cornea@intel.com>
Fixes: 8520f38099cc ("USB: change hub initialization sleeps to delayed_work")
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Some USB device / host controller combinations seem to have problems
with Link Power Management. For example, Steinar found that his xHCI
controller wouldn't handle bandwidth calculations correctly for two
video cards simultaneously when LPM was enabled, even though the bus
had plenty of bandwidth available.
This patch introduces a new quirk flag for devices that should remain
disabled for LPM, and creates quirk entries for Steinar's devices.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Steinar H. Gunderson <sgunderson@bigfoot.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
|
Currently usb_port_resume waits for up to 2 seconds for CONNECT
status for SS devices only. This change will do the same thing for
non-SS devices even though the reason is a little different. This
will fix an issue where VBUS is turned off during system wide
"suspend to ram" and some 2.0 devices take greater than the current
max of 100ms to show connected after VBUS is enabled. This is most
commonly seen on hard drive based devices and USB3.0 devices plugged
into a 2.0 only port.
Signed-off-by: Al Cooper <alcooperx@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
|
Joe Perches
Mike Looijmans
Felipe Balbi
Greg Kroah-Hartman
Daniel Drake
Mathias Nyman
Dmitry Fleytman
Alan Stern
Peter Chen
Eugene Korenevsky
Johan Hovold
Guenter Roeck
Ingo Molnar
Geert Uytterhoeven
Linus Torvalds
Yonglong Wu
Wolfram Sang
Viresh Kumar
Chris Bainbridge
Oliver Neukum
Saurabh Sengar
Heiner Kallweit
Du, Changbin
Geliang Tang
Al Cooper