Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The USB completion callback does not disable interrupts while acquiring
the ->lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: linux-input@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
For mouse and joystick devices user can change the polling interval
via usbhid.mousepoll and usbhid.jspoll.
Implement the same thing for keyboards, so user can
reduce(or increase) input latency this way.
This has been tested with a Cooler Master Devastator with
kbpoll=32, resulting in delay between events of 32 ms(values were taken
from evtest).
Signed-off-by: Filip Alac <filipalac@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Two Jabra speakerphone devices were added to the ignore list in 2013,
because the device HID interfaces didn't work well with kernel usbhid
driver, and could cause volume key event storm.
See the original commit:
Commit 31b9779cb2 ("HID: ignore Jabra speakerphones HID interface")
Modify hid_lookup_quirk() to consider the firmware version of these two
devices, so that only versions older than a known good version are
ignored.
Signed-off-by: Niels Skou Olsen <nolsen@jabra.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
usbhid has a list of dynamic quirks in addition to a list of static quirks.
There is not much USB specific in that, so move this part of the module
in core so we can have one central place for quirks.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The hid descriptor identifies the length and type of subordinate
descriptors for a device. If the received hid descriptor is smaller than
the size of the struct hid_descriptor, it is possible to cause
out-of-bounds.
In addition, if bNumDescriptors of the hid descriptor have an incorrect
value, this can also cause out-of-bounds while approaching hdesc->desc[n].
So check the size of hid descriptor and bNumDescriptors.
BUG: KASAN: slab-out-of-bounds in usbhid_parse+0x9b1/0xa20
Read of size 1 at addr ffff88006c5f8edf by task kworker/1:2/1261
CPU: 1 PID: 1261 Comm: kworker/1:2 Not tainted
4.14.0-rc1-42251-gebb2c2437d80 #169
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:16
dump_stack+0x292/0x395 lib/dump_stack.c:52
print_address_description+0x78/0x280 mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351
kasan_report+0x22f/0x340 mm/kasan/report.c:409
__asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:427
usbhid_parse+0x9b1/0xa20 drivers/hid/usbhid/hid-core.c:1004
hid_add_device+0x16b/0xb30 drivers/hid/hid-core.c:2944
usbhid_probe+0xc28/0x1100 drivers/hid/usbhid/hid-core.c:1369
usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361
really_probe drivers/base/dd.c:413
driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
__device_attach_driver+0x230/0x290 drivers/base/dd.c:653
bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
__device_attach+0x26e/0x3d0 drivers/base/dd.c:710
device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
device_add+0xd0b/0x1660 drivers/base/core.c:1835
usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932
generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174
usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266
really_probe drivers/base/dd.c:413
driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
__device_attach_driver+0x230/0x290 drivers/base/dd.c:653
bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
__device_attach+0x26e/0x3d0 drivers/base/dd.c:710
device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
device_add+0xd0b/0x1660 drivers/base/core.c:1835
usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457
hub_port_connect drivers/usb/core/hub.c:4903
hub_port_connect_change drivers/usb/core/hub.c:5009
port_event drivers/usb/core/hub.c:5115
hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195
process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119
worker_thread+0x221/0x1850 kernel/workqueue.c:2253
kthread+0x3a1/0x470 kernel/kthread.c:231
ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
Cc: stable@vger.kernel.org
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Jaejoong Kim <climbbb.kim@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
(introduced by 686fef928b ("timer: Prepare to change timer callback
argument type")) to pass the timer pointer explicitly. Adds pointer back to
hid_device for multitouch.
[jkosina@suse.cz: extend changelog a little bit as asked for by Benjamin]
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: linux-input@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Although HID itself is transport-agnostic, occasionally a driver may
want to interact with the low-level transport that a device is connected
through. To do this, we need to know what kind of bus is in use. The
first guess may be to look at the 'bus' field of the 'struct hid_device',
but this field may be emulated in some cases (e.g. uhid).
More ideally, we can check which ll_driver a device is using. This
function introduces a 'hid_is_using_ll_driver' function and makes the
'struct hid_ll_driver' of the four most common transports accessible
through hid.h.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Acked-By: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Even though the IO for devices with "always poll" quirk is already running,
we still need to set HID_OPENED bit in usbhid->iofl so the interrupt
handler does not ignore the data coming from the device.
Reported-by: Olof Johansson <olof@lixom.net>
Tested-by: Olof Johansson <olof@lixom.net>
Fixes: e399396a6b ("HID: usbhid: remove custom locking from usbhid_open...")
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Now that HID core enforces serialization of transport driver open/close
calls we can remove custom locking from usbhid driver.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Instead of checking hid->open (that we plan on having HID core manage) in
hid_start_in(), let's allocate a couple of new flags: HID_IN_POLLING and
HID_OPENED, and use them to decide whether we should be submitting URBs or
not.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Instead of calling into usbhid code directly, let's use the standard
accessors for the transport HID drivers, and stop clobbering their error
codes with -EIO.
This also allows us to remove usbhid_get/put_power(), leaving only
usbhid_power().
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Instead of calling into usbhid code directly, let's use the standard
accessors for the transport HID drivers, and stop clobbering their errors
with -EIO.
This also allows us make usbhid_open and close static.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
It looks like a bunch of devices do not like to be polled
for their reports at init time. When you look into the details,
it seems that for those that are requiring the quirk
HID_QUIRK_NO_INIT_REPORTS, the driver fails to retrieve part
of the features/inputs while others (more generic) work.
IMO, it should be acceptable to remove the need for the quirk
in the general case. On the small amount of cases where
we actually need to read the current values, the driver
in charge (hid-mt or wacom) already retrieves the features
manually.
There are 2 cases where we might need to retrieve the reports at
init:
1. hiddev devices with specific use-space tool
2. a device that would require the driver to fetch a specific
feature/input at plug
For case 2, I have seen this a few time on hid-multitouch. It
is solved in hid-multitouch directly by fetching the feature.
I hope it won't be too common and this can be solved on a per-case
basis (crossing fingers).
For case 1, we moved the implementation of HID_QUIRK_NO_INIT_REPORTS
in hiddev. When somebody starts calling ioctls that needs an initial
update, the hiddev device will fetch the initial state of the reports
to mimic the current behavior. This adds a small amount of time during
the first HIDIOCGUSAGE(S), but it should be acceptable in
most cases. To keep the currently known broken devices, we have to
keep around HID_QUIRK_NO_INIT_REPORTS, but the scope will only be
for hiddev.
Note that I don't think hidraw would be affected and I checked that
the FF drivers that need to interact with the report fields are all
using output reports, which are not initialized by
usbhid_init_reports().
NO_INIT_INPUT_REPORTS is then replaced by HID_QUIRK_NO_INIT_REPORTS:
there is no point keeping it for just one device.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Use a more common logging style and remove the unnecessary
OOM messages as there is default dump_stack when OOM.
Miscellanea:
o Hoist an assignment in an if
o Realign arguments
o Realign a deeply indented if descendent above a printk
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
For mouse devices we can currently change the polling interval
via usbhid.mousepoll. Implement the same thing for joysticks, so
users can reduce input latency this way.
This has been tested with a Logitech RumblePad 2 with jspoll=2,
resulting in a polling rate of 500Hz (verified with evhz).
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Local "#define DRIVER_LICENSE" obfuscates which license is used
in MODULE_LICENSE(). "fgrep -R MODULE_LICENSE" is more informative
when the string is hard coded in MODULE_LICENSE.
Signed-off-by: Grant Grundler <grundler@google.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Function hid_post_reset() should return negative error codes on failures.
However, in its implementation, it incorrectly returns 1. This patch fixes the
bug, returning proper error codes on failures.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The usbhid driver has inconsistently duplicated code in its post-reset,
resume, and reset-resume pathways.
reset-resume doesn't check HID_STARTED before trying to
restart the I/O queues.
resume fails to clear the HID_SUSPENDED flag if HID_STARTED
isn't set.
resume calls usbhid_restart_queues() with usbhid->lock held
and the others call it without holding the lock.
The first item in particular causes a problem following a reset-resume
if the driver hasn't started up its I/O. URB submission fails because
usbhid->urbin is NULL, and this triggers an unending reset-retry loop.
This patch fixes the problem by creating a new subroutine,
hid_restart_io(), to carry out all the common activities. It also
adds some checks that were missing in the original code:
After a reset, there's no need to clear any halted endpoints.
After a resume, if a reset is pending there's no need to
restart any I/O until the reset is finished.
After a resume, if the interrupt-IN endpoint is halted there's
no need to submit the input URB until the halt has been
cleared.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Daniel Fraga <fragabr@gmail.com>
Tested-by: Daniel Fraga <fragabr@gmail.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The critical section protected by usbhid->lock in hid_ctrl() is too
big and because of this it causes a recursive deadlock. "Too big" means
the case statement and the call to hid_input_report() do not need to be
protected by the spinlock (no URB operations are done inside them).
The deadlock happens because in certain rare cases drivers try to grab
the lock while handling the ctrl irq which grabs the lock before them
as described above. For example newer wacom tablets like 056a:033c try
to reschedule proximity reads from wacom_intuos_schedule_prox_event()
calling hid_hw_request() -> usbhid_request() -> usbhid_submit_report()
which tries to grab the usbhid lock already held by hid_ctrl().
There are two ways to get out of this deadlock:
1. Make the drivers work "around" the ctrl critical region, in the
wacom case for ex. by delaying the scheduling of the proximity read
request itself to a workqueue.
2. Shrink the critical region so the usbhid lock protects only the
instructions which modify usbhid state, calling hid_input_report()
with the spinlock unlocked, allowing the device driver to grab the
lock first, finish and then grab the lock afterwards in hid_ctrl().
This patch implements the 2nd solution.
Signed-off-by: Ioan-Adrian Ratiu <adi@adirat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
If an event is discarded the device stays idle. Just reverse the order of
check and marking busy.
Found by code inspection.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
It was reported that after 10-20 reboots, a usb keyboard plugged
into a docking station would not work unless it was replugged in.
Using usbmon, it turns out the interrupt URBs were streaming with
callback errors of -71 for some reason. The hid-core.c::hid_io_error was
supposed to retry and then reset, but the reset wasn't really happening.
The check for HID_NO_BANDWIDTH was inverted. Fix was simple.
Tested by reporter and locally by me by unplugging a keyboard halfway until I
could recreate a stream of errors but no disconnect.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
During open() it is unnecessary to wait for the device to flush
stale inputs if the device is polled while closed due to a quirk
or opening fails.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
In several hid drivers it is necessary to calculate the length of an
hid_report. This patch exports the existing static function hid_report_len of
hid-core.c as an inline function in hid.h
Signed-off-by: Mathieu Magnaudet <mathieu.magnaudet@enac.fr>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
When events occurs while no one is listening to the node (hid->open == 0
and usb_kill_urb() called) some events are still stacked somewhere in
the USB (kernel or device?) stack. When the node gets reopened, these
events are drained, and this results in spurious touch down/up, or mouse
button clicks.
The problem was spotted with touchscreens in fdo bug #81781 [1], but it
actually occurs with any mouse using hid-generic or touchscreen.
A way to reproduce it is to call:
$ xinput disable 9 ; sleep 5 ; xinput enable 9
With 9 being the device ID for the touchscreen/mouse. During the "sleep",
produce some touch events or click events. When "xinput enable" is called,
at least one click is generated.
This patch tries to fix this by draining the queue for 50 msec and
during this time frame, not forwarding these old events to the hid layer.
Hans completed the explanation:
"""
Devices like mice (basically any hid device) will have a fifo
on the device side, when we stop submitting urbs to get hid reports from
it, that fifo will fill up, and when we resume we will get whatever
is there in that fifo.
"""
[1] https://bugs.freedesktop.org/show_bug.cgi?id=81781
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Add quirk to make sure that a device is always polled for input events
even if it hasn't been opened.
This is needed for devices that disconnects from the bus unless the
interrupt endpoint has been polled at least once or when not responding
to an input event (e.g. after having shut down X).
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This patch changes the way usbhid carries out Clear-Halt and reset.
Currently, after a Clear-Halt on the interrupt-IN endpoint, the driver
immediately restarts the interrupt URB, even if the Clear-Halt failed.
This doesn't work out well when the reason for the failure was that
the device was disconnected (when a low- or full-speed device is
connected through a hub to an EHCI controller, transfer errors caused
by disconnection are reported as stalls by the hub). Instead now the
driver will attempt a reset after a failed Clear-Halt.
The way resets are carried out is also changed. Now the driver will
call usb_queue_reset_device() instead of calling usb_reset_device()
directly. This avoids a deadlock that would arise when a device is
unplugged: The hid_reset() routine runs as a workqueue item, a reset
attempt after the device has been unplugged will fail, failure will
cause usbhid to be unbound, and the disconnect routine will try to do
cancel_work_sync(). The usb_queue_reset_device() implementation is
carefully written to handle scenarios like this one properly.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The quirks_param array is located in the BSS, no need to explicitly
initialize it with NULL.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Nobody calls hid_output_raw_report anymore, and nobody should.
We can now remove the various implementation in the different
transport drivers and the declarations.
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
hid_out_raw_report is going to be obsoleted as it is not part of the
unified HID low level transport documentation
(Documentation/hid/hid-transport.txt)
To do so, we need to introduce two new quirks:
* HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP: this quirks prevents the
transport driver to use the interrupt channel to send output report
(and thus force to use HID_REQ_SET_REPORT command)
* HID_QUIRK_SKIP_OUTPUT_REPORT_ID: this one forces usbhid to not
include the report ID in the buffer it sends to the device through
HID_REQ_SET_REPORT in case of an output report
This also fixes a regression introduced in commit 3a75b24949
(HID: hidraw: replace hid_output_raw_report() calls by appropriates ones).
The hidraw API was not able to communicate with the PS3 SixAxis
controllers in USB mode.
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Tested-by: Antonio Ospite <ao2@ao2.it>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
If there is no urbout when sending a output report, ENOSYS (Function
not implemented) is a better error than EIO (I/O error).
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
dev->hid_get_raw_report(X) and hid_hw_raw_request(X, HID_REQ_GET_REPORT)
are strictly equivalent. Switch the hid subsystem to the hid_hw notation
and remove the field .hid_get_raw_report in struct hid_device.
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Well, no use to keep twice the same code.
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Add raw_request, set_raw_report and output_report transport-driver functions to
the USB HID driver.
Signed-off-by: Frank Praznik <frank.praznik@oh.rr.com>
Acked-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Some multitouch screens do not like to be polled for input reports.
However, the Win8 spec says that all touches should be sent during
each report, making the initialization of reports unnecessary.
The Win7 spec is less precise, so do not use this for those devices.
Add the quirk HID_QUIRK_NO_INIT_INPUT_REPORTS so that we do not have to
introduce a quirk for each problematic device. This quirk makes the driver
behave the same way the Win 8 does. It actually retrieves the features,
but not the inputs.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Tested-by: Srinivas Pandruvada<srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
HID core provides the same functionality as we do, so drop the custom
hidinput_input_event() handler.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Report fields can be updated from HID drivers unlocked via
hid_set_field(). It is protected by input_lock in HID core so only a
single input event is handled at a time. USBHID can thus update the field
unlocked and doesn't conflict with any HID vendor/device drivers. Note,
many HID drivers make heavy use of hid_set_field() in that way.
But usbhid also schedules a work to gather multiple LED changes in a
single report. Hence, we used to lock the LED field update so the work can
read a consistent state. However, hid_set_field() only writes a single
integer field, which is guaranteed to be allocated all the time. So the
worst possible race-condition is a garbage read on the LED field.
Therefore, there is no need to protect the update. In fact, the only thing
that is prevented by locking hid_set_field(), is an LED update while the
scheduled work currently writes an older LED update out. However, this
means, a new work is scheduled directly when the old one is done writing
the new state to the device. So we actually _win_ by not protecting the
write and allowing the write to be combined with the current write. A new
worker is still scheduled, but will not write any new state. So the LED
will not blink unnecessarily on the device.
Assume we have the LED set to 0. Two request come in which enable the LED
and immediately disable it. The current situation with two CPUs would be:
usb_hidinput_input_event() | hid_led()
---------------------------------+----------------------------------
spin_lock(&usbhid->lock);
hid_set_field(1);
spin_unlock(&usbhid->lock);
schedule_work(...);
spin_lock(&usbhid->lock);
__usbhid_submit_report(..1..);
spin_unlock(&usbhid->lock);
spin_lock(&usbhid->lock);
hid_set_field(0);
spin_unlock(&usbhid->lock);
schedule_work(...);
spin_lock(&usbhid->lock);
__usbhid_submit_report(..0..);
spin_unlock(&usbhid->lock);
With the locking removed, we _might_ end up with (look at the changed
__usbhid_submit_report() parameters in the first try!):
usb_hidinput_input_event() | hid_led()
---------------------------------+----------------------------------
hid_set_field(1);
schedule_work(...);
spin_lock(&usbhid->lock);
hid_set_field(0);
schedule_work(...);
__usbhid_submit_report(..0..);
spin_unlock(&usbhid->lock);
... next work ...
spin_lock(&usbhid->lock);
__usbhid_submit_report(..0..);
spin_unlock(&usbhid->lock);
As one can see, we no longer send the "LED ON" signal as it is disabled
immediately afterwards and the following "LED OFF" request overwrites the
pending "LED ON".
It is important to note that hid_set_field() is not atomic, so we might
also end up with any other value. But that doesn't matter either as we
_always_ schedule the next work with a correct value and schedule_work()
acts as memory barrier, anyways. So in the worst case, we run
__usbhid_submit_report(..<garbage>..) in the first case and the following
__usbhid_submit_report() will write the correct value. But LED states are
booleans so any garbage will be converted to either 0 or 1 and the remote
device will never see invalid requests.
Why all this? It avoids any custom locking around hid_set_field() in
usbhid and finally allows us to provide a generic hidinput_input_event()
handler for all HID transport drivers.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
usbhid_set_leds() is only used inside of usbhid/hid-core.c so no need to
export it.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
implement() is setting bytes in LE data stream. In case the data is not
aligned to 64bits, it reads past the allocated buffer. It doesn't really
change any value there (it's properly bitmasked), but in case that this
read past the boundary hits a page boundary, pagefault happens when
accessing 64bits of 'x' in implement(), and kernel oopses.
This happens much more often when numbered reports are in use, as the
initial 8bit skip in the buffer makes the whole process work on values
which are not aligned to 64bits.
This problem dates back to attempts in 2005 and 2006 to make implement()
and extract() as generic as possible, and even back then the problem
was realized by Adam Kroperlin, but falsely assumed to be impossible
to cause any harm:
http://www.mail-archive.com/linux-usb-devel@lists.sourceforge.net/msg47690.html
I have made several attempts at fixing it "on the spot" directly in
implement(), but the results were horrible; the special casing for processing
last 64bit chunk and switching to different math makes it unreadable mess.
I therefore took a path to allocate a few bytes more which will never make
it into final report, but are there as a cushion for all the 64bit math
operations happening in implement() and extract().
All callers of hid_output_report() are converted at the same time to allocate
the buffer by newly introduced hid_alloc_report_buf() helper.
Bruno noticed that the whole raw_size test can be dropped as well, as
hid_alloc_report_buf() makes sure that the buffer is always of a proper
size.
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Pull HID updates from Jiri Kosina:
- hid driver transport cleanup, finalizing the long-desired decoupling
of core from transport layers, by Benjamin Tissoires and Henrik
Rydberg
- support for hybrid finger/pen multitouch HID devices, by Benjamin
Tissoires
- fix for long-standing issue in Logitech unifying driver sometimes not
inializing properly due to device specifics, by Andrew de los Reyes
- Wii remote driver updates to support 2nd generation of devices, by
David Herrmann
- support for Apple IR remote
- roccat driver now supports new devices (Roccat Kone Pure, IskuFX), by
Stefan Achatz
- debugfs locking fixes in hid debug interface, by Jiri Kosina
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (43 commits)
HID: protect hid_debug_list
HID: debug: break out hid_dump_report() into hid-debug
HID: Add PID for Japanese version of NE4K keyboard
HID: hid-lg4ff add support for new version of DFGT wheel
HID: icade: u16 which never < 0
HID: clarify Magic Mouse Kconfig description
HID: appleir: add support for Apple ir devices
HID: roccat: added media key support for Kone
HID: hid-lenovo-tpkbd: remove doubled hid_get_drvdata
HID: i2c-hid: fix length for set/get report in i2c hid
HID: wiimote: parse reduced status reports
HID: wiimote: add 2nd generation Wii Remote IDs
HID: wiimote: use unique battery names
HID: hidraw: warn if userspace headers are outdated
HID: multitouch: force BTN_STYLUS for pen devices
HID: multitouch: append " Pen" to the name of the stylus input
HID: multitouch: add handling for pen in dual-sensors device
HID: multitouch: change touch sensor detection in mt_input_configured()
HID: multitouch: do not map usage from non used reports
HID: multitouch: breaks out touch handling in specific functions
...
If suspend callback fails in system sleep context, usb core will
ignore the failure and let the system sleep go ahead further, so this
patch doesn't recover device under this situation, otherwise
may cause resume() confused.
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some drivers send the idle command directly to underlying device,
creating an unwanted dependency on the underlying transport layer.
This patch adds hid_hw_idle() to the interface, thereby removing
usbhid from the lion share of the drivers.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This removes most of the dependencies between hid drivers and usbhid.
The patch was constructed by replacing all occurences of
usbhid_wait_io() by its hid_hw_wait() counterpart.
Then, drivers not requiring USB_HID anymore have their USB_HID
dependency cleaned in the Kconfig file.
As of today, few drivers are still requiring an explicit USB layer
dependency:
* ntrig (a patch is on its way)
* multitouch (one patch following and another on its way)
* lenovo tpkbd
* roccat
* sony
The last three are two deeply using direct calls to the usb subsystem
to be able to be cleaned right now.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Thomas Gleixner