When reading an extra descriptor, we need to properly check the minimum
and maximum size allowed, to prevent from invalid data being sent by a
device.
Reported-by: Hui Peng <benquike@gmail.com>
Reported-by: Mathias Payer <mathias.payer@nebelwelt.net>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hui Peng <benquike@gmail.com>
Signed-off-by: Mathias Payer <mathias.payer@nebelwelt.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the USB hub core waits for 50 ms after enumerating the
device. This was added to help "some high speed devices" to
enumerate (b789696af8 "[PATCH] USB: relax usbcore reset timings").
On some devices, the time-to-active is important, so we provide
a per-port option to reduce the time to what the USB specification
requires: 10 ms.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
USB 3.2 specification adds Dual-lane support, doubling the maximum
SuperSpeedPlus data rate from 10Gbps to 20Gbps.
Dual-lane takes into use a second set of rx and tx wires/pins in the
Type-C cable and connector.
Add "rx_lanes" and "tx_lanes" variables to struct usb_device to store
the numer of lanes in use. Number of lanes can be read using the extended
port status hub request that was introduced in USB 3.1.
Extended port status rx and tx lane count are zero based, maximum
lanes supported by non inter-chip (SSIC) USB 3.2 is 2 (dual lane) with
rx and tx lane count symmetric. SSIC devices support asymmetric lanes
up to 4 lanes per direction.
If extended port status is not available then default to one lane.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB SS and SSP hubs provide wHubDelay values on their hub descriptor
which we should inform the USB Device about.
The USB Specification 3.0 explains, on section 9.4.11, how to
calculate the value and how to issue the request. Note that a
USB_REQ_SET_ISOCH_DELAY is valid on all device states (Default,
Address, Configured), we just *chose* to issue it from Address state
right after successfully fetching the USB Device Descriptor.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The URB_NO_FSBR flag has never really been used. It was introduced as
a potential way for UHCI to minimize PCI bus usage (by not attempting
full-speed bulk and control transfers more than once per frame), but
the flag was not set by any drivers.
There's no point in keeping it around. This patch simplifies the API
by removing it. Unfortunately, it does have to be kept as part of the
usbfs ABI, but at least we can document in
include/uapi/linux/usbdevice_fs.h that it doesn't do anything.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are no big surprising changes in this cycle, yet not too
boring, either. The biggest change from diffstat POV is the removal
of the legacy OSS driver codes that have been already disabled for a
long time. This will bring a few trivial merge conflicts.
As new features in ASoC side, there are two things: a new AC97 bus
implementation and AMD Stony platform support. Both include the
relevant changes shared with other subsystems, e.g. AC97 MFD changes
and DRM AMD changes.
Some other highlighted topics are:
- A bunch of USB-audio drivers got the hardening against the malicious
device accesses with a new helper code for endpoint sanity check.
- Lots of cleanups for ASoC Intel platform code, including support for
their open source audio firmware.
- Continued ASoC core componentization works.
- Support for scaling MCLK with sample rate in ASoC simple-card.
- Stabler PCM hot-unplug capability, especially for ASoC usages.
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Merge tag 'sound-4.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound updates from Takashi Iwai:
"There are no big surprising changes in this cycle, yet not too boring,
either. The biggest change from diffstat POV is the removal of the
legacy OSS driver codes that have been already disabled for a long
time. This will bring a few trivial merge conflicts.
As new features in ASoC side, there are two things: a new AC97 bus
implementation and AMD Stony platform support. Both include the
relevant changes shared with other subsystems, e.g. AC97 MFD changes
and DRM AMD changes.
Some other highlighted topics are:
- A bunch of USB-audio drivers got the hardening against the
malicious device accesses with a new helper code for endpoint
sanity check
- Lots of cleanups for ASoC Intel platform code, including support
for their open source audio firmware
- Continued ASoC core componentization works
- Support for scaling MCLK with sample rate in ASoC simple-card
- Stabler PCM hot-unplug capability, especially for ASoC usages"
* tag 'sound-4.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (302 commits)
Documentation: sound: hd-audio: notes.rst
ASoC: bcm2835: Support left/right justified and DSP modes
ASoC: bcm2835: Enforce full symmetry
ASoC: bcm2835: Support additional samplerates up to 384kHz
ASoC: bcm2835: Add support for TDM modes
ASoC: add mclk-fs support to audio graph card
ASoC: add mclk-fs to audio graph card binding
ASoC: rt5514: work around link error
ASoC: rt5514: mark PM functions as __maybe_unused
ASoC: rt5663: Check the JD status in the button pushing
ASoC: amd: Modified DMA transfer Mechanism for Playback
ASoC: rt5645: Wait for 400msec before concluding on value of RT5645_VENDOR_ID2
ASoC: sun4i-codec: fixed 32bit audio capture support for H3/H2+
ASoC: da7213: add support for DSP modes
ASoC: sun8i-codec: Add a comment on the LRCK inversion
ASoC: sun8i-codec: Set the BCLK divider
ASoC: rt5663: Delay and retry reading rt5663 ID register
ASoC: amd: use do_div rather than 64 bit division to fix 32 bit builds
ASoC: cs42l56: Fix reset GPIO name in example DT binding
ASoC: rt5514-spi: check irq status to schedule data copy in resume function
...
Here is the big set of USB and PHY driver updates for 4.15-rc1.
There is the usual amount of gadget and xhci driver updates, along with
phy and chipidea enhancements. There's also a lot of SPDX tags and
license boilerplate cleanups as well, which provide some churn in the
diffstat.
Other major thing is the typec code that moved out of staging and into
the "real" part of the drivers/usb/ tree, which was nice to see happen.
All of these have been in linux-next with no reported issues for a
while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY updates from Greg KH:
"Here is the big set of USB and PHY driver updates for 4.15-rc1.
There is the usual amount of gadget and xhci driver updates, along
with phy and chipidea enhancements. There's also a lot of SPDX tags
and license boilerplate cleanups as well, which provide some churn in
the diffstat.
Other major thing is the typec code that moved out of staging and into
the "real" part of the drivers/usb/ tree, which was nice to see
happen.
All of these have been in linux-next with no reported issues for a
while"
* tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (263 commits)
usb: gadget: f_fs: Fix use-after-free in ffs_free_inst
USB: usbfs: compute urb->actual_length for isochronous
usb: core: message: remember to reset 'ret' to 0 when necessary
USB: typec: Remove remaining redundant license text
USB: typec: add SPDX identifiers to some files
USB: renesas_usbhs: rcar?.h: add SPDX tags
USB: chipidea: ci_hdrc_tegra.c: add SPDX line
USB: host: xhci-debugfs: add SPDX lines
USB: add SPDX identifiers to all remaining Makefiles
usb: host: isp1362-hcd: remove a couple of redundant assignments
USB: adutux: remove redundant variable minor
usb: core: add a new usb_get_ptm_status() helper
usb: core: add a 'type' parameter to usb_get_status()
usb: core: introduce a new usb_get_std_status() helper
usb: core: rename usb_get_status() 'type' argument to 'recip'
usb: core: add Status Type definitions
USB: gadget: Remove redundant license text
USB: gadget: function: Remove redundant license text
USB: gadget: udc: Remove redundant license text
USB: gadget: legacy: Remove redundant license text
...
The biggest thing this release has been the conversion of the AC98 bus
to the driver model, that's been a long time coming so thanks to Robert
Jarzmik for his dedication there. Due to there being some AC97 MFD
there's a few fairly large changes in input and the MFD layer, mainly to
the wm97xx driver.
There's also some drivers/drm changes to support the new AMD Stoney
platform, these are shared with the DRM subsystem and should be being
merged via both.
Within the subsystem the overwhelming bulk of the changes is in the
Intel drivers which continue to need lots of cleanups and fixes, this
release they've also gained support for their open source firmware.
There's also some large changs in the core as Morimoto-san continues to
mirror operations into the component level in preparation for conversion
of drivers to that.
- The AC97 bus has finally caught up with the driver model thanks to
some dedicated and persistent work from Robert Jarzmik.
- Continued work from Morimoto-san on moving us towards being able to
use components for everything.
- Lots of cleanups for the Intel platform code, including support for
their open source audio firmware.
- Support for scaling MCLK with sample rate in simple-card.
- Support for AMD Stoney platform.
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Merge tag 'asoc-v4.15' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v4.15
The biggest thing this release has been the conversion of the AC98 bus
to the driver model, that's been a long time coming so thanks to Robert
Jarzmik for his dedication there. Due to there being some AC97 MFD
there's a few fairly large changes in input and the MFD layer, mainly to
the wm97xx driver.
There's also some drivers/drm changes to support the new AMD Stoney
platform, these are shared with the DRM subsystem and should be being
merged via both.
Within the subsystem the overwhelming bulk of the changes is in the
Intel drivers which continue to need lots of cleanups and fixes, this
release they've also gained support for their open source firmware.
There's also some large changs in the core as Morimoto-san continues to
mirror operations into the component level in preparation for conversion
of drivers to that.
- The AC97 bus has finally caught up with the driver model thanks to
some dedicated and persistent work from Robert Jarzmik.
- Continued work from Morimoto-san on moving us towards being able to
use components for everything.
- Lots of cleanups for the Intel platform code, including support for
their open source audio firmware.
- Support for scaling MCLK with sample rate in simple-card.
- Support for AMD Stoney platform.
Drivers who are interested in the PTM status stype, should use this
new helper to make sure they issue the correct GetStatus message.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This new 'type' parameter will allows interested drivers to request
for PTM status or Standard status.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
This makes it a lot clearer that we're expecting a recipient as the
argument. A follow-up patch will use the argument 'type' as the status
type selector (standard or ptm).
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds a new helper function to perform a sanity check of the
given URB to see whether it contains a valid endpoint. It's a light-
weight version of what usb_submit_urb() does, but without the kernel
warning followed by the stack trace, just returns an error code.
Especially for a driver that doesn't parse the descriptor but fills
the URB with the fixed endpoint (e.g. some quirks for non-compliant
devices), this kind of check is preferable at the probe phase before
actually submitting the urb.
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Since when we got rid of usbfs, the /proc/bus/usb is now
elsewhere. Fix references for it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several drivers have implemented their endpoint look-up loops in such a
way that they have picked the last endpoint descriptor of the specified
type should more than one such descriptor exist.
To avoid any regressions, add corresponding helpers to lookup endpoints
by searching the endpoint descriptors in reverse order.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many USB drivers iterate over the available endpoints to find required
endpoints of a specific type and direction. Typically the endpoints are
required for proper function and a missing endpoint should abort probe.
To facilitate code reuse, add a helper to retrieve common endpoints
(bulk or interrupt, in or out) and four wrappers to find a single
endpoint.
Note that the helpers are marked as __must_check to serve as a reminder
to always verify that all expected endpoints are indeed present. This
also means that any optional endpoints, typically need to be looked up
through separate calls.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For xhci-hcd platform device, all the DMA parameters are not
configured properly, notably dma ops for dwc3 devices.
The idea here is that you pass in the parent of_node along with
the child device pointer, so it would behave exactly like the
parent already does. The difference is that it also handles all
the other attributes besides the mask.
sysdev will represent the physical device, as seen from firmware
or bus.Splitting the usb_bus->controller field into the
Linux-internal device (used for the sysfs hierarchy, for printks
and for power management) and a new pointer (used for DMA,
DT enumeration and phy lookup) probably covers all that we really
need.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
Tested-by: Baolin Wang <baolin.wang@linaro.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Tested-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Sinjan Kumar <sinjank@codeaurora.org>
Cc: David Fisher <david.fisher1@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "Thang Q. Nguyen" <tqnguyen@apm.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Leo Li <pku.leo@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a USB driver is bound to an interface (either through probing or
by claiming it) or is unbound from an interface, the USB core always
disables Link Power Management during the transition and then
re-enables it afterward. The reason is because the driver might want
to prevent hub-initiated link power transitions, in which case the HCD
would have to recalculate the various LPM parameters. This
recalculation takes place when LPM is re-enabled and the new
parameters are sent to the device and its parent hub.
However, if the driver does not want to prevent hub-initiated link
power transitions then none of this work is necessary. The parameters
don't need to be recalculated, and LPM doesn't need to be disabled and
re-enabled.
It turns out that disabling and enabling LPM can be time-consuming,
enough so that it interferes with user programs that want to claim and
release interfaces rapidly via usbfs. Since the usbfs kernel driver
doesn't set the disable_hub_initiated_lpm flag, we can speed things up
and get the user programs to work by leaving LPM alone whenever the
flag isn't set.
And while we're improving the way disable_hub_initiated_lpm gets used,
let's also fix its kerneldoc.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Matthew Giassa <matthew@giassa.net>
CC: Mathias Nyman <mathias.nyman@intel.com>
CC: <stable@vger.kernel.org>
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: 638139eb95 ("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>
SS+ also expresses intervals in units of 125ms. Testing must
be for SS or faster, not SS exactly.
Signed-off-by: Oliver neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
LTM is also defined for SS+. The correct test is to check for anything
slower than SS not exactly SS.
Signed-off-by: Oliver Neukum <ONeukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB 3.1 devices that support precision time measurement have an
additional PTM cabaility descriptor as part of the full BOS descriptor
Look for this descriptor while parsing the BOS descriptor, and store it in
struct usb_hub_bos if it exists.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB 3.1 devices can return a new SuperSpeedPlus isoc endpoint companion
descriptor for a isochronous endpoint that requires more than 48K bytes
per Service Interval.
The new descriptor immediately follows the old USB 3.0 SuperSpeed Endpoint
Companion and will provide a new BytesPerInterval value.
It is parsed and stored in struct usb_host_endpoint with the other endpoint
related descriptors, and should be used by USB3.1 capable hosts to reserve
bus time in the schedule.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
232275a USB: fix substandard locking for the sysfs files
introduced needed locking into sysfs operations on USB devices
It, however, uses uninterruptible sleep and if the error
handling is on extreme cases of sleep lengths of 10s of seconds
are possible. Unless we are removing the device we should use
interruptible sleep.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB bus numbering is based on directly dealing with bitmaps and
defines a separate list of busses.
This can be simplified and unified by using existing idr functionality.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 8306095fd2 ("USB: Disable USB 3.0 LPM in critical sections.")
adds usb3_lpm_enabled member to struct usb_device. There is no reference
to this member now. Hence, it could be removed.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 655fe4effe ("usbcore: add sysfs support to xHCI usb3
hardware LPM") introduced usb3_hardware_lpm sysfs node. This
doesn't show the correct status of USB3 U1 and U2 LPM status.
This patch fixes this by replacing usb3_hardware_lpm with two
nodes, usb3_hardware_lpm_u1 (for U1) and usb3_hardware_lpm_u2
(for U2), and recording the U1/U2 LPM status in right places.
This patch should be back-ported to kernels as old as 4.3,
that contains Commit 655fe4effe ("usbcore: add sysfs support
to xHCI usb3 hardware LPM").
Cc: stable@vger.kernel.org
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a device supports usb 3.1 SupeerSpeedPlus Gen2 speeds it povides
a SuperSpeedPlus device capability descriptor as a part of its
BOS descriptor. If we find one while parsing the BOS then save it
togeter with the other device capabilities found in the BOS
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The attribute authorized shows the authorization state for an interface.
Signed-off-by: Stefan Koch <stefan.koch10@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Every USB Host controller should use this new
macro to define for how long resume signalling
should be driven on the bus.
Currently, almost every single USB controller
is using a 20ms timeout for resume signalling.
That's problematic for two reasons:
a) sometimes that 20ms timer expires a little
before 20ms, which makes us fail certification
b) some (many) devices actually need more than
20ms resume signalling.
Sure, in case of (b) we can state that the device
is against the USB spec, but the fact is that
we have no control over which device the certification
lab will use. We also have no control over which host
they will use. Most likely they'll be using a Windows
PC which, again, we have no control over how that
USB stack is written and how long resume signalling
they are using.
At the end of the day, we must make sure Linux passes
electrical compliance when working as Host or as Device
and currently we don't pass compliance as host because
we're driving resume signallig for exactly 20ms and
that confuses certification test setup resulting in
Certification failure.
Cc: <stable@vger.kernel.org> # v3.10+
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
The USB stack provides a mechanism for drivers to request an
asynchronous device reset (usb_queue_reset_device()). The mechanism
uses a work item (reset_ws) embedded in the usb_interface structure
used by the driver, and the reset is carried out by a work queue
routine.
The asynchronous reset can race with driver unbinding. When this
happens, we try to cancel the queued reset before unbinding the
driver, on the theory that the driver won't care about any resets once
it is unbound.
However, thanks to the fact that lockdep now tracks work queue
accesses, this can provoke a lockdep warning in situations where the
device reset causes another interface's driver to be unbound; see
http://marc.info/?l=linux-usb&m=141893165203776&w=2
for an example. The reason is that the work routine for reset_ws in
one interface calls cancel_queued_work() for the reset_ws in another
interface. Lockdep thinks this might lead to a work routine trying to
cancel itself. The simplest solution is not to cancel queued resets
when unbinding drivers.
This means we now need to acquire a reference to the usb_interface
when queuing a reset_ws work item and to drop the reference when the
work routine finishes. We also need to make sure that the
usb_interface structure doesn't outlive its parent usb_device; this
means acquiring and dropping a reference when the interface is created
and destroyed.
In addition, cancelling a queued reset can fail (if the device is in
the middle of an earlier reset), and this can cause usb_reset_device()
to try to rebind an interface that has been deallocated (see
http://marc.info/?l=linux-usb&m=142175717016628&w=2 for details).
Acquiring the extra references prevents this failure.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Russell King - ARM Linux <linux@arm.linux.org.uk>
Reported-by: Olivier Sobrie <olivier@sobrie.be>
Tested-by: Olivier Sobrie <olivier@sobrie.be>
Cc: stable <stable@vger.kernel.org> # 3.19
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The descriptor member `bNumEndpoints' is plural.
Signed-off-by: Chris Rorvick <chris@rorvick.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is
selected) PM_RUNTIME is always set if PM is set, so quite a few
depend on CONFIG_PM (or even dropped in some cases).
Replace CONFIG_PM_RUNTIME with CONFIG_PM in the USB core code
and documentation.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With this patch, USB activity can be signaled by blinking a LED. There
are two triggers, one for activity on USB host and one for USB gadget.
Both triggers should work with all host/device controllers. Tested only
with musb.
Performace: I measured performance overheads on ARM Cortex-A8 (TI
AM335x) running on 600 MHz.
Duration of usb_led_activity():
- with no LED attached to the trigger: 2 ± 1 µs
- with one GPIO LED attached to the trigger: 2 ± 1 µs or 8 ± 2 µs (two peaks in histogram)
Duration of functions calling usb_led_activity() (with this patch
applied and no LED attached to the trigger):
- __usb_hcd_giveback_urb(): 10 - 25 µs
- usb_gadget_giveback_request(): 2 - 6 µs
Signed-off-by: Michal Sojka <sojka@merica.cz>
Acked-by: Felipe Balbi <balbi@ti.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch creates a separate instance of the usb_address0 mutex for each USB
bus, and attaches it to the usb_bus device struct. This allows devices on
separate buses to be enumerated in parallel; saving time.
In the current code, there is a single, global instance of the usb_address0
mutex which is used for all devices on all buses. This isn't completely
necessary, as this mutex is only needed to prevent address0 collisions for
devices on the *same* bus (usb 2.0 spec, sec 4.6.1). This superfluous coverage
can cause additional delay in system resume on systems with multiple hosts
(up to several seconds depending on what devices are attached).
Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here's the big USB pull request for 3.15-rc1.
The normal set of patches, lots of controller driver updates, and a
smattering of individual USB driver updates as well.
All have been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB patches from Greg KH:
"Here's the big USB pull request for 3.15-rc1.
The normal set of patches, lots of controller driver updates, and a
smattering of individual USB driver updates as well.
All have been in linux-next for a while"
* tag 'usb-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (249 commits)
xhci: Transition maintainership to Mathias Nyman.
USB: disable reset-resume when USB_QUIRK_RESET is set
USB: unbind all interfaces before rebinding any
usb: phy: Add ulpi IDs for SMSC USB3320 and TI TUSB1210
usb: gadget: tcm_usb_gadget: stop format strings
usb: gadget: f_fs: add missing spinlock and mutex unlock
usb: gadget: composite: switch over to ERR_CAST()
usb: gadget: inode: switch over to memdup_user()
usb: gadget: f_subset: switch over to PTR_RET
usb: gadget: lpc32xx_udc: fix wrong clk_put() sequence
USB: keyspan: remove dead debugging code
USB: serial: add missing newlines to dev_<level> messages.
USB: serial: add missing braces
USB: serial: continue to write on errors
USB: serial: continue to read on errors
USB: serial: make bulk_out_size a lower limit
USB: cypress_m8: fix potential scheduling while atomic
devicetree: bindings: document lsi,zevio-usb
usb: chipidea: add support for USB OTG controller on LSI Zevio SoCs
usb: chipidea: imx: Use dev_name() for ci_hdrc name to distinguish USBs
...
Since it is needed outside usbcore and exposed in include/linux/usb.h,
it conflicts with enum dev_state in rt2x00 wireless driver.
Mark it as usb specific to avoid conflicts in the future.
Signed-off-by: Valentina Manea <valentina.manea.m@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A device should not be able to be used concurrently both by
the server and the client. Claiming the port used by the
shared device ensures no interface drivers bind to it and
that it is not usable from the server.
Signed-off-by: Valentina Manea <valentina.manea.m@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a preparation patch for adding support for bulk streams to usbfs.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
So that it can be used in other places too.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This reverts commit 35773dac5f. It's a
hack that caused regressions in the usb-storage and userspace USB
drivers that use usbfs and libusb. Commit 70cabb7d992f "xhci 1.0: Limit
arbitrarily-aligned scatter gather." should fix the issues seen with the
ax88179_178a driver on xHCI 1.0 hosts, without causing regressions.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org # 3.12
This driver was previously an interface driver. Since USB/IP
exports a whole device, not just an interface, it would make
sense to be a device driver.
This patch also modifies the way userspace sees and uses a
shared device:
* the usbip_status file is no longer created for interface 0, but for
the whole device (such as
/sys/devices/pci0000:00/0000:00:01.2/usb1/1-1/usbip_status).
* per interface information, such as interface class or protocol, is
no longer sent/received; only device specific information is
transmitted.
* since the driver was moved one level below in the USB architecture,
there is no need to bind/unbind each interface, just the device as a
whole.
Signed-off-by: Valentina Manea <valentina.manea.m@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Often, usb drivers need some driver_info to get a device to work. To
have access to driver_info when using new_id, allow to pass a reference
vendor:product tuple from which new_id will inherit driver_info.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Section 4.11.7.1 of rev 1.0 of the xhci specification states that a link TRB
can only occur at a boundary between underlying USB frames (512 bytes for
high speed devices).
If this isn't done the USB frames aren't formatted correctly and, for example,
the USB3 ethernet ax88179_178a card will stop sending (while still receiving)
when running a netperf tcp transmit test with (say) and 8k buffer.
This should be a candidate for stable, the ax88179_178a driver defaults to
gso and tso enabled so it passes a lot of fragmented skb to the USB stack.
Notes from Sarah:
Discussion: http://marc.info/?l=linux-usb&m=138384509604981&w=2
This patch fixes a long-standing xHCI driver bug that was revealed by a
change in 3.12 in the usb-net driver. Commit
638c5115a7 "USBNET: support DMA SG" added
support to use bulk endpoint scatter-gather (urb->sg). Only the USB
ethernet drivers trigger this bug, because the mass storage driver sends
sg list entries in page-sized chunks.
This patch only fixes the issue for bulk endpoint scatter-gather. The
problem will still occur for periodic endpoints, because hosts will
interpret no-op transfers as a request to skip a service interval, which
is not what we want.
Luckily, the USB core isn't set up for scatter-gather on isochronous
endpoints, and no USB drivers use scatter-gather for interrupt
endpoints. Document this known limitation so that developers won't try
to use urb->sg for interrupt endpoints until this issue is fixed. The
more comprehensive fix would be to allow link TRBs in the middle of the
endpoint ring and revert this patch, but that fix would touch too much
code to be allowed in for stable.
This patch should be backported to kernels as old as 3.12, that contain
the commit 638c5115a7 "USBNET: support DMA
SG". Without this patch, the USB network device gets wedged, and stops
sending packets. Mark Lord confirms this patch fixes the regression:
http://marc.info/?l=linux-netdev&m=138487107625966&w=2
Signed-off-by: David Laight <david.laight@aculab.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Tested-by: Mark Lord <mlord@pobox.com>
Cc: stable@vger.kernel.org
How it's supposed to work:
--------------------------
USB 2.0 Link PM is a lower power state that some newer USB 2.0 devices
support. USB 3.0 devices certified by the USB-IF are required to
support it if they are plugged into a USB 2.0 only port, or a USB 2.0
cable is used. USB 2.0 Link PM requires both a USB device and a host
controller that supports USB 2.0 hardware-enabled LPM.
USB 2.0 Link PM is designed to be enabled once by software, and the host
hardware handles transitions to the L1 state automatically. The premise
of USB 2.0 Link PM is to be able to put the device into a lower power
link state when the bus is idle or the device NAKs USB IN transfers for
a specified amount of time.
...but hardware is broken:
--------------------------
It turns out many USB 3.0 devices claim to support USB 2.0 Link PM (by
setting the LPM bit in their USB 2.0 BOS descriptor), but they don't
actually implement it correctly. This manifests as the USB device
refusing to respond to transfers when it is plugged into a USB 2.0 only
port under the Haswell-ULT/Lynx Point LP xHCI host.
These devices pass the xHCI driver's simple test to enable USB 2.0 Link
PM, wait for the port to enter L1, and then bring it back into L0. They
only start to break when L1 entry is interleaved with transfers.
Some devices then fail to respond to the next control transfer (usually
a Set Configuration). This results in devices never enumerating.
Other mass storage devices (such as a later model Western Digital My
Passport USB 3.0 hard drive) respond fine to going into L1 between
control transfers. They ACK the entry, come out of L1 when the host
needs to send a control transfer, and respond properly to those control
transfers. However, when the first READ10 SCSI command is sent, the
device NAKs the data phase while it's reading from the spinning disk.
Eventually, the host requests to put the link into L1, and the device
ACKs that request. Then it never responds to the data phase of the
READ10 command. This results in not being able to read from the drive.
Some mass storage devices (like the Corsair Survivor USB 3.0 flash
drive) are well behaved. They ACK the entry into L1 during control
transfers, and when SCSI commands start coming in, they NAK the requests
to go into L1, because they need to be at full power.
Not all USB 3.0 devices advertise USB 2.0 link PM support. My Point
Grey USB 3.0 webcam advertises itself as a USB 2.1 device, but doesn't
have a USB 2.0 BOS descriptor, so we don't enable USB 2.0 Link PM. I
suspect that means the device isn't certified.
What do we do about it?
-----------------------
There's really no good way for the kernel to test these devices.
Therefore, the kernel needs to disable USB 2.0 Link PM by default, and
distros will have to enable it by writing 1 to the sysfs file
/sys/bus/usb/devices/../power/usb2_hardware_lpm. Rip out the xHCI Link
PM test, since it's not sufficient to detect these buggy devices, and
don't automatically enable LPM after the device is addressed.
This patch should be backported to kernels as old as 3.11, that
contain the commit a558ccdcc7 "usb: xhci:
add USB2 Link power management BESL support". Without this fix, some
USB 3.0 devices will not enumerate or work properly under USB 2.0 ports
on Haswell-ULT systems.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
Mathias Payer