History log of /linux/drivers/usb/core/hub.h (Results 1 – 25 of 50)
Revision Date Author Comments
# 31e7f6c0 25-Mar-2024 Javier Carrasco <javier.carrasco@wolfvision.net>

usb: misc: onboard_hub: rename to onboard_dev

This patch prepares onboad_hub to support non-hub devices by renaming
the driver files and their content, the headers and their references.

The comment

usb: misc: onboard_hub: rename to onboard_dev

This patch prepares onboad_hub to support non-hub devices by renaming
the driver files and their content, the headers and their references.

The comments and descriptions have been slightly modified to keep
coherence and account for the specific cases that only affect onboard
hubs (e.g. peer-hub).

The "hub" variables in functions where "dev" (and similar names) variables
already exist have been renamed to onboard_dev for clarity, which adds a
few lines in cases where more than 80 characters are used.

No new functionality has been added.

Acked-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Javier Carrasco <javier.carrasco@wolfvision.net>
Link: https://lore.kernel.org/r/20240325-onboard_xvf3500-v8-2-29e3f9222922@wolfvision.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# ee113b86 15-Mar-2024 Alan Stern <stern@rowland.harvard.edu>

USB: core: Add hub_get() and hub_put() routines

Create hub_get() and hub_put() routines to encapsulate the kref_get()
and kref_put() calls in hub.c. The new routines will be used by the
next patch

USB: core: Add hub_get() and hub_put() routines

Create hub_get() and hub_put() routines to encapsulate the kref_get()
and kref_put() calls in hub.c. The new routines will be used by the
next patch in this series.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/604da420-ae8a-4a9e-91a4-2d511ff404fb@rowland.harvard.edu
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 11110783 11-Oct-2023 Heikki Krogerus <heikki.krogerus@linux.intel.com>

usb: Inform the USB Type-C class about enumerated devices

The Type-C port drivers can make PM related decisions based
on is the device USB3 or USB2.

Suggested-by: Benson Leung <bleung@chromium.org>

usb: Inform the USB Type-C class about enumerated devices

The Type-C port drivers can make PM related decisions based
on is the device USB3 or USB2.

Suggested-by: Benson Leung <bleung@chromium.org>
Tested-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20231011105825.320062-3-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# f74a7afc 30-Aug-2023 Ricardo Cañuelo <ricardo.canuelo@collabora.com>

usb: hub: Guard against accesses to uninitialized BOS descriptors

Many functions in drivers/usb/core/hub.c and drivers/usb/core/hub.h
access fields inside udev->bos without checking if it was alloca

usb: hub: Guard against accesses to uninitialized BOS descriptors

Many functions in drivers/usb/core/hub.c and drivers/usb/core/hub.h
access fields inside udev->bos without checking if it was allocated and
initialized. If usb_get_bos_descriptor() fails for whatever
reason, udev->bos will be NULL and those accesses will result in a
crash:

BUG: kernel NULL pointer dereference, address: 0000000000000018
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 5 PID: 17818 Comm: kworker/5:1 Tainted: G W 5.15.108-18910-gab0e1cb584e1 #1 <HASH:1f9e 1>
Hardware name: Google Kindred/Kindred, BIOS Google_Kindred.12672.413.0 02/03/2021
Workqueue: usb_hub_wq hub_event
RIP: 0010:hub_port_reset+0x193/0x788
Code: 89 f7 e8 20 f7 15 00 48 8b 43 08 80 b8 96 03 00 00 03 75 36 0f b7 88 92 03 00 00 81 f9 10 03 00 00 72 27 48 8b 80 a8 03 00 00 <48> 83 78 18 00 74 19 48 89 df 48 8b 75 b0 ba 02 00 00 00 4c 89 e9
RSP: 0018:ffffab740c53fcf8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffa1bc5f678000 RCX: 0000000000000310
RDX: fffffffffffffdff RSI: 0000000000000286 RDI: ffffa1be9655b840
RBP: ffffab740c53fd70 R08: 00001b7d5edaa20c R09: ffffffffb005e060
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: ffffab740c53fd3e R14: 0000000000000032 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffffa1be96540000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000018 CR3: 000000022e80c005 CR4: 00000000003706e0
Call Trace:
hub_event+0x73f/0x156e
? hub_activate+0x5b7/0x68f
process_one_work+0x1a2/0x487
worker_thread+0x11a/0x288
kthread+0x13a/0x152
? process_one_work+0x487/0x487
? kthread_associate_blkcg+0x70/0x70
ret_from_fork+0x1f/0x30

Fall back to a default behavior if the BOS descriptor isn't accessible
and skip all the functionalities that depend on it: LPM support checks,
Super Speed capabilitiy checks, U1/U2 states setup.

Signed-off-by: Ricardo Cañuelo <ricardo.canuelo@collabora.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20230830100418.1952143-1-ricardo.canuelo@collabora.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 83cb2604 08-Jun-2023 Roy Luo <royluo@google.com>

usb: core: add sysfs entry for usb device state

Expose usb device state to userland as the information is useful in
detecting non-compliant setups and diagnosing enumeration failures.
For example:
-

usb: core: add sysfs entry for usb device state

Expose usb device state to userland as the information is useful in
detecting non-compliant setups and diagnosing enumeration failures.
For example:
- End-to-end signal integrity issues: the device would fail port reset
repeatedly and thus be stuck in POWERED state.
- Charge-only cables (missing D+/D- lines): the device would never enter
POWERED state as the HC would not see any pullup.

What's the status quo?
We do have error logs such as "Cannot enable. Maybe the USB cable is bad?"
to flag potential setup issues, but there's no good way to expose them to
userspace.

Why add a sysfs entry in struct usb_port instead of struct usb_device?
The struct usb_device is not device_add() to the system until it's in
ADDRESS state hence we would miss the first two states. The struct
usb_port is a better place to keep the information because its life
cycle is longer than the struct usb_device that is attached to the port.

Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202306042228.e532af6e-oliver.sang@intel.com
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Roy Luo <royluo@google.com>
Message-ID: <20230608015913.1679984-1-royluo@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 430d57f5 07-Nov-2022 Ray Chi <raychi@google.com>

usb: core: stop USB enumeration if too many retries

When a broken USB accessory connects to a USB host, usbcore might
keep doing enumeration retries. If the host has a watchdog mechanism,
the kernel

usb: core: stop USB enumeration if too many retries

When a broken USB accessory connects to a USB host, usbcore might
keep doing enumeration retries. If the host has a watchdog mechanism,
the kernel panic will happen on the host.

This patch provides an attribute early_stop to limit the numbers of retries
for each port of a hub. If a port was marked with early_stop attribute,
unsuccessful connection attempts will fail quickly. In addition, if an
early_stop port has failed to initialize, it will ignore all future
connection events until early_stop attribute is clear.

Signed-off-by: Ray Chi <raychi@google.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20221107072754.3336357-1-raychi@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 3a6bf4a0 30-Jun-2022 Matthias Kaehlcke <mka@chromium.org>

usb: core: hub: Create platform devices for onboard hubs in hub_probe()

Call onboard_hub_create/destroy_pdevs() from hub_probe/disconnect()
to create/destroy platform devices for onboard USB hubs th

usb: core: hub: Create platform devices for onboard hubs in hub_probe()

Call onboard_hub_create/destroy_pdevs() from hub_probe/disconnect()
to create/destroy platform devices for onboard USB hubs that may be
connected to the hub. The onboard hubs must have nodes in the
device tree.

onboard_hub_create/destroy_pdevs() are NOPs unless
CONFIG_USB_ONBOARD_HUB=y/m.

Also add a field to struct usb_hub to keep track of the onboard hub
platform devices that are owned by the hub.

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lore.kernel.org/r/20220630123445.v24.4.Ic9dd36078f9d803de82ca01a6700c58b8e4de27e@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# f061f43d 07-Jun-2022 Michael Grzeschik <m.grzeschik@pengutronix.de>

usb: hub: port: add sysfs entry to switch port power

In some cases the port of an hub needs to be disabled or switched off
and on again. E.g. when the connected device needs to be re-enumerated.
Or

usb: hub: port: add sysfs entry to switch port power

In some cases the port of an hub needs to be disabled or switched off
and on again. E.g. when the connected device needs to be re-enumerated.
Or it needs to be explicitly disabled while the rest of the usb tree
stays working.

For this purpose this patch adds an sysfs switch to enable/disable the
port on any hub. In the case the hub is supporting power switching, the
power line will be disabled to the connected device.

When the port gets disabled, the associated device gets disconnected and
removed from the logical usb tree. No further device will be enumerated
on that port until the port gets enabled again.

Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Link: https://lore.kernel.org/r/20220607114522.3359148-1-m.grzeschik@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 90d28fb5 10-Apr-2021 Chunfeng Yun <chunfeng.yun@mediatek.com>

usb: core: reduce power-on-good delay time of root hub

Return the exactly delay time given by root hub descriptor,
this helps to reduce resume time etc.

Due to the root hub descriptor is usually pr

usb: core: reduce power-on-good delay time of root hub

Return the exactly delay time given by root hub descriptor,
this helps to reduce resume time etc.

Due to the root hub descriptor is usually provided by the host
controller driver, if there is compatibility for a root hub,
we can fix it easily without affect other root hub

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1618017645-12259-1-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# e6075b66 28-Mar-2020 Nishad Kamdar <nishadkamdar@gmail.com>

USB: core: Use the correct style for SPDX License Identifier

This patch corrects the SPDX License Identifier style in
header files related to USB Core.
For C header files Documentation/process/licen

USB: core: Use the correct style for SPDX License Identifier

This patch corrects the SPDX License Identifier style in
header files related to USB Core.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Link: https://lore.kernel.org/r/20200328091844.GA3648@nishad
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 1208f9e1 06-Feb-2020 Hardik Gajjar <hgajjar@de.adit-jv.com>

USB: hub: Fix the broken detection of USB3 device in SMSC hub

Renesas R-Car H3ULCB + Kingfisher Infotainment Board is either not able
to detect the USB3.0 mass storage devices or is detecting those

USB: hub: Fix the broken detection of USB3 device in SMSC hub

Renesas R-Car H3ULCB + Kingfisher Infotainment Board is either not able
to detect the USB3.0 mass storage devices or is detecting those as
USB2.0 high speed devices.

The explanation given by Renesas is that, due to a HW issue, the XHCI
driver does not wake up after going to sleep on connecting a USB3.0
device.

In order to mitigate that, disable the auto-suspend feature
specifically for SMSC hubs from hub_probe() function, as a quirk.

Renesas Kingfisher Infotainment Board has two USB3.0 ports (CN2) which
are connected via USB5534B 4-port SuperSpeed/Hi-Speed, low-power,
configurable hub controller.

[1] SanDisk USB 3.0 device detected as USB-2.0 before the patch
[ 74.036390] usb 5-1.1: new high-speed USB device number 4 using xhci-hcd
[ 74.061598] usb 5-1.1: New USB device found, idVendor=0781, idProduct=5581, bcdDevice= 1.00
[ 74.069976] usb 5-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 74.077303] usb 5-1.1: Product: Ultra
[ 74.080980] usb 5-1.1: Manufacturer: SanDisk
[ 74.085263] usb 5-1.1: SerialNumber: 4C530001110208116550

[2] SanDisk USB 3.0 device detected as USB-3.0 after the patch
[ 34.565078] usb 6-1.1: new SuperSpeed Gen 1 USB device number 3 using xhci-hcd
[ 34.588719] usb 6-1.1: New USB device found, idVendor=0781, idProduct=5581, bcdDevice= 1.00
[ 34.597098] usb 6-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 34.604430] usb 6-1.1: Product: Ultra
[ 34.608110] usb 6-1.1: Manufacturer: SanDisk
[ 34.612397] usb 6-1.1: SerialNumber: 4C530001110208116550

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Hardik Gajjar <hgajjar@de.adit-jv.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1580989763-32291-1-git-send-email-hgajjar@de.adit-jv.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 8eb58994 08-Jan-2019 Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

usb: hub: add retry routine after intr URB submit error

The hub sends hot-plug events to the host trough it's interrupt URB. The
driver takes care of completing the URB and re-submitting it. Complet

usb: hub: add retry routine after intr URB submit error

The hub sends hot-plug events to the host trough it's interrupt URB. The
driver takes care of completing the URB and re-submitting it. Completion
errors are handled in the hub_event() work, yet submission errors are
ignored, rendering the device unresponsive. All further events are lost.

It is fairly hard to find this issue in the wild, since you have to time
the USB hot-plug event with the URB submission failure. For instance it
could be the system running out of memory or some malfunction in the USB
controller driver. Nevertheless, it's pretty reasonable to think it'll
happen sometime. One can trigger this issue using eBPF's function
override feature (see BCC's inject.py script).

This patch adds a retry routine to the event of a submission error. The
HUB driver will try to re-submit the URB once every second until it's
successful or the HUB is disconnected.

As some USB subsystems already take care of this issue, the
implementation was inspired from usbhid/hid_core.c's.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: Oliver Neukum <oneukum@suse.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 25244227 28-May-2018 Nicolas Boichat <drinkcat@chromium.org>

usb: hub: Per-port setting to use old enumeration scheme

The "old" enumeration scheme is considerably faster (it takes
~244ms instead of ~356ms to get the descriptor).

It is currently only possible

usb: hub: Per-port setting to use old enumeration scheme

The "old" enumeration scheme is considerably faster (it takes
~244ms instead of ~356ms to get the descriptor).

It is currently only possible to use the old scheme globally
(/sys/module/usbcore/parameters/old_scheme_first), which is not
desirable as the new scheme was introduced to increase compatibility
with more devices.

However, in our case, we care about time-to-active for a specific
USB device (which we make the firmware for), on a specific port
(that is pogo-pin based: not a standard USB port). This new
sysfs option makes it possible to use the old scheme on a single
port only.

Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 1cbd53c8 20-Mar-2018 Richard Leitner <richard.leitner@skidata.com>

usb: core: introduce per-port over-current counters

For some userspace applications information on the number of
over-current conditions at specific USB hub ports is relevant.

In our case we have a

usb: core: introduce per-port over-current counters

For some userspace applications information on the number of
over-current conditions at specific USB hub ports is relevant.

In our case we have a series of USB hardware (using the cp210x driver)
which communicates using a proprietary protocol. These devices sometimes
trigger an over-current situation on some hubs. In case of such an
over-current situation the USB devices offer an interface for reducing
the max used power. As these conditions are quite rare and imply
performance reductions of the device we don't want to reduce the max
power always.

Therefore give user-space applications the possibility to react
adequately by introducing an over_current_counter in the usb port struct
which is exported via sysfs.

Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# f9d4d453 03-Nov-2017 Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: core: Remove redundant license text

Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be remove

USB: core: Remove redundant license text

Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 5fd54ace 03-Nov-2017 Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 0cdd49a1 10-Dec-2015 Mathias Nyman <mathias.nyman@linux.intel.com>

usb: Support USB 3.1 extended port status request

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 po

usb: Support USB 3.1 extended port status request

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>

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# 513072d9 14-Nov-2015 Lu Baolu <baolu.lu@linux.intel.com>

usb: core: lpm: add sysfs node for usb3 lpm permit

USB3 LPM is default on in Linux kernel if both xHCI host controller
and the USB devices declare to be LPM-capable. Unfortunately, some
devices are

usb: core: lpm: add sysfs node for usb3 lpm permit

USB3 LPM is default on in Linux kernel if both xHCI host controller
and the USB devices declare to be LPM-capable. Unfortunately, some
devices are known to work well with LPM disabled, but to be broken
if LPM is enabled, although it declares the LPM capability. Users
won't be able to use this kind of devices, until someone puts them
in the kernel blacklist and gets the kernel upgraded.

This patch adds a sysfs node to permit or forbit USB3 LPM U1 or U2
entry for a port. The settings apply to both before and after device
enumeration. Supported values are "0" - neither u1 nor u2 permitted,
"u1" - only u1 is permitted, "u2" - only u2 is permitted, "u1_u2" -
both u1 and u2 are permitted. With this interface, users can use an
LPM-unfriendly USB device on a released Linux kernel.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Zhuang Jin Can <jin.can.zhuang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 32a69589 19-Sep-2014 Petr Mladek <pmladek@suse.cz>

usb: hub: convert khubd into workqueue

There is no need to have separate kthread for handling USB hub events.
It is more elegant to use the workqueue framework.

The workqueue is allocated as freeza

usb: hub: convert khubd into workqueue

There is no need to have separate kthread for handling USB hub events.
It is more elegant to use the workqueue framework.

The workqueue is allocated as freezable because the original thread was
freezable as well.

Also it is allocated as ordered because the code is not ready for parallel
processing of hub events, see choose_devnum().

struct usb_hub is passed via the work item. Therefore we do not need
hub_event_list.

Also hub_thread() is not longer needed. It would call only hub_event().
The rest of the code did manipulate the kthread and it is handled by the
workqueue framework now.

kick_khubd is renamed to kick_hub_wq() to make the function clear. And the
protection against races is done another way, see below.

hub_event_lock has been removed. It cannot longer be used to protect struct
usb_hub between hub_event() and hub_disconnect(). Instead we need to get
hub->kref already in kick_hub_wq().

The lock is not really needed for the other scenarios as well. queue_work()
returns whether it succeeded. We could revert the needed operations
accordingly. This is enough to avoid duplicity and inconsistencies.

Yes, the removed lock causes that there is not longer such a strong
synchronization between scheduling the work and manipulating
hub->disconnected.

But kick_hub_wq() must never be called together with hub_disconnect()
otherwise even the original code would have failed. Any callers are
responsible for this.

Therefore the only problem is that hub_disconnect() could be called in parallel
with hub_event(). But this was possible even in the past. struct usb_hub is
still guarded by hub->kref and released in hub_events() when needed.

Note that the source file is still full of the obsolete "khubd" strings.
Let's remove them in a follow up patch. This patch already is complex enough.

Thanks a lot Alan Stern <stern@rowland.harvard.edu> for code review, many useful
tips and guidance. Also thanks to Tejun Heo <tj@kernel.org> for hints how to
allocate the workqueue.

Signed-off-by: Petr Mladek <pmladek@suse.cz>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 3cd12f91 29-May-2014 Dan Williams <dan.j.williams@intel.com>

usb: force warm reset to break link re-connect livelock

Resuming a powered down port sometimes results in the port state being
stuck in the training sequence.

hub 3-0:1.0: debounce: port 1: total

usb: force warm reset to break link re-connect livelock

Resuming a powered down port sometimes results in the port state being
stuck in the training sequence.

hub 3-0:1.0: debounce: port 1: total 2000ms stable 0ms status 0x2e0
port1: can't get reconnection after setting port power on, status -110
hub 3-0:1.0: port 1 status 0000.02e0 after resume, -19
usb 3-1: can't resume, status -19
hub 3-0:1.0: logical disconnect on port 1

In the case above we wait for the port re-connect timeout of 2 seconds
and observe that the port status is USB_SS_PORT_LS_POLLING (although it
is likely toggling between this state and USB_SS_PORT_LS_RX_DETECT).
This is indicative of a case where the device is failing to progress the
link training state machine.

It is resolved by issuing a warm reset to get the hub and device link
state machines back in sync.

hub 3-0:1.0: debounce: port 1: total 2000ms stable 0ms status 0x2e0
usb usb3: port1 usb_port_runtime_resume requires warm reset
hub 3-0:1.0: port 1 not warm reset yet, waiting 50ms
usb 3-1: reset SuperSpeed USB device number 2 using xhci_hcd

After a reconnect timeout when we expect the device to be present, force
a warm reset of the device. Note that we can not simply look at the
link status to determine if a warm reset is required as any of the
training states USB_SS_PORT_LS_POLLING, USB_SS_PORT_LS_RX_DETECT, or
USB_SS_PORT_LS_COMP_MOD are valid states that do not indicate the need
for warm reset by themselves.

Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Vincent Palatin <vpalatin@chromium.org>
Cc: Lan Tianyu <tianyu.lan@intel.com>
Cc: Ksenia Ragiadakou <burzalodowa@gmail.com>
Cc: Vivek Gautam <gautam.vivek@samsung.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Sunil Joshi <joshi@samsung.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Acked-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...


# e3d10505 17-Jun-2014 Dan Williams <dan.j.williams@intel.com>

usb: fix hub-port pm_runtime_enable() vs runtime pm transitions

Commit 9262c19d14c4 "usb: disable port power control if not supported in
wHubCharacteristics" gated enabling runtime pm for usb_port d

usb: fix hub-port pm_runtime_enable() vs runtime pm transitions

Commit 9262c19d14c4 "usb: disable port power control if not supported in
wHubCharacteristics" gated enabling runtime pm for usb_port devices on
whether the parent hub supports power control, which causes a
regression. The port must still be allowed to carry out runtime pm
callbacks and receive a -EAGAIN or -EBUSY result. Otherwise the
usb_port device will transition to the pm error state and trigger the
same for the child usb_device.

Prior to the offending commit usb_hub_create_port_device() arranged for
runtime pm to be disabled is dev_pm_qos_expose_flags() failed. Instead,
force the default state of PM_QOS_FLAG_NO_POWER_OFF flag to be set prior
to enabling runtime pm. If that policy can not be set then fail
registration.

Report: http://marc.info/?l=linux-usb&m=140290586301336&w=2
Fixes: 9262c19d14c4 ("usb: disable port power control if not supported in wHubCharacteristics")
Reported-by: Bjørn Mork <bjorn@mork.no>
Reported-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 5c79a1e3 21-May-2014 Dan Williams <dan.j.williams@intel.com>

usb: introduce port status lock

In general we do not want khubd to act on port status changes that are
the result of in progress resets or USB runtime PM operations.
Specifically port power control

usb: introduce port status lock

In general we do not want khubd to act on port status changes that are
the result of in progress resets or USB runtime PM operations.
Specifically port power control testing has been able to trigger an
unintended disconnect in hub_port_connect_change(), paraphrasing:

if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
udev->state != USB_STATE_NOTATTACHED) {
if (portstatus & USB_PORT_STAT_ENABLE) {
/* Nothing to do */
} else if (udev->state == USB_STATE_SUSPENDED &&
udev->persist_enabled) {
...
} else {
/* Don't resuscitate */;
}
}

...by falling to the "Don't resuscitate" path or missing
USB_PORT_STAT_CONNECTION because usb_port_resume() was in the middle of
modifying the port status.

So, we want a new lock to hold off khubd for a given port while the
child device is being suspended, resumed, or reset. The lock ordering
rules are now usb_lock_device() => usb_lock_port(). This is mandated by
the device core which may hold the device_lock on the usb_device before
invoking usb_port_{suspend|resume} which in turn take the status_lock on
the usb_port. We attempt to hold the status_lock for the duration of a
port_event() run, and drop/re-acquire it when needing to take the
device_lock. The lock is also dropped/re-acquired during
hub_port_reconnect().

This patch also deletes hub->busy_bits as all use cases are now covered
by port PM runtime synchronization or the port->status_lock and it
pushes down usb_device_lock() into usb_remote_wakeup().

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 7ad3c470 21-May-2014 Dan Williams <dan.j.williams@intel.com>

usb: block suspension of superspeed port while hispeed peer is active

ClearPortFeature(PORT_POWER) on a usb3 port places the port in either a
DSPORT.Powered-off-detect / DSPORT.Powered-off-reset loo

usb: block suspension of superspeed port while hispeed peer is active

ClearPortFeature(PORT_POWER) on a usb3 port places the port in either a
DSPORT.Powered-off-detect / DSPORT.Powered-off-reset loop, or the
DSPORT.Powered-off state. There is no way to ensure that RX
terminations will persist in this state, so it is possible a device will
degrade to its usb2 connection. Prevent this by blocking power-off of a
usb3 port while its usb2 peer is active, and powering on a usb3 port
before its usb2 peer.

By default the latency between peer power-on events is 0. In order for
the device to not see usb2 active while usb3 is still powering up inject
the hub recommended power_on_good delay. In support of satisfying the
power_on_good delay outside of hub_power_on() refactor the places where
the delay is consumed to call a new hub_power_on_good_delay() helper.

Finally, because this introduces several new checks for whether a port
is_superspeed, cache that disctinction at port creation so that we don't
need to keep looking up the parent hub device.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
[alan]: add a 'superspeed' flag to the port
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# d5c3834e 21-May-2014 Dan Williams <dan.j.williams@intel.com>

usb: make usb_port flags atomic, rename did_runtime_put to child_usage

We want to manipulate ->did_runtime_put in usb_port_runtime_resume(),
but we don't want that to collide with other updates. Mo

usb: make usb_port flags atomic, rename did_runtime_put to child_usage

We want to manipulate ->did_runtime_put in usb_port_runtime_resume(),
but we don't want that to collide with other updates. Move usb_port
flags to new port-bitmap fields in usb_hub. "did_runtime_put" is renamed
"child_usage_bits" to reflect that it is strictly standing in for the
fact that usb_devices are not the device_model children of their parent
port.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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# 3bfd659b 21-May-2014 Dan Williams <dan.j.williams@intel.com>

usb: find internal hub tier mismatch via acpi

ACPI identifies peer ports by setting their 'group_token' and
'group_position' _PLD data to the same value. If a platform has tier
mismatch [1] , ACPI

usb: find internal hub tier mismatch via acpi

ACPI identifies peer ports by setting their 'group_token' and
'group_position' _PLD data to the same value. If a platform has tier
mismatch [1] , ACPI can override the default (USB3 defined) peer port
association for internal hubs. External hubs follow the default peer
association scheme.

Location data is cached as an opaque cookie in usb_port_location data.

Note that we only consider the group_token and group_position attributes
from the _PLD data as ACPI specifies that group_token is a unique
identifier.

When we find port location data for a port then we assume that the
firmware will also describe its peer port. This allows the
implementation to only ever set the peer once. This leads to a question
about what happens when a pm runtime event occurs while the peer
associations are still resolving. Since we only ever set the peer
information once, a USB3 port needs to be prevented from suspending
while its ->peer pointer is NULL (implemented in a subsequent patch).

There is always the possibility that firmware mis-identifies the ports,
but there is not much the kernel can do in that case.

[1]: xhci 1.1 appendix D figure 131
[2]: acpi 5 section 6.1.8

[alan]: don't do default peering when acpi data present
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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