During unbinding the driver was dereferencing a pointer to memory
already freed by power_supply_unregister().
Driver was freeing its internal description of battery through pointers
stored in power_supply structure. However, because the core owns the
power supply instance, after calling power_supply_unregister() this
memory is freed and the driver cannot access these members.
Fix this by storing the pointer to internal description of battery in a
local variable before calling power_supply_unregister(), so the pointer
remains valid.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reported-by: H.J. Lu <hjl.tools@gmail.com>
Fixes: 297d716f62 ("power_supply: Change ownership from driver to core")
Cc: <stable@vger.kernel.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
We need to emit EV_SYN/SYN_REPORT between key press and release, otherwise
userspace is allowed to "swallow" the event.
[jkosina@suse.com: Dmitry says that he's observing this behavior with
Plantronics headset]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
There are too many bangs in this conditional; therefore
remove them while still maintaining the same logic.
Signed-off-by: James C Boyd <jcboyd.dev@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
GCC reports a -Wlogical-not-parentheses warning here; therefore
add parentheses to shut it up and to express our intent more.
Signed-off-by: James C Boyd <jcboyd.dev@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Pull HID updates from Jiri Kosina:
- quite a few firmware fixes for RMI driver by Andrew Duggan
- huion and uclogic drivers have been substantially overlaping in
functionality laterly. This redundancy is fixed by hid-huion driver
being merged into hid-uclogic; work done by Benjamin Tissoires and
Nikolai Kondrashov
- i2c-hid now supports ACPI GPIO interrupts; patch from Mika Westerberg
- Some of the quirks, that got separated into individual drivers, have
historically had EXPERT dependency. As HID subsystem matured (as
well as the individual drivers), this made less and less sense. This
dependency is now being removed by patch from Jean Delvare
- Logitech lg4ff driver received a couple of improvements for mode
switching, by Michal Malý
- multitouch driver now supports clickpads, patches by Benjamin
Tissoires and Seth Forshee
- hid-sensor framework received a substantial update; namely support
for Custom and Generic pages is being added; work done by Srinivas
Pandruvada
- wacom driver received substantial update; it now supports
i2c-conntected devices (Mika Westerberg), Bamboo PADs are now
properly supported (Benjamin Tissoires), much improved battery
reporting (Jason Gerecke) and pen proximity cleanups (Ping Cheng)
- small assorted fixes and device ID additions
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (68 commits)
HID: sensor: Update document for custom sensor
HID: sensor: Custom and Generic sensor support
HID: debug: fix error handling in hid_debug_events_read()
Input - mt: Fix input_mt_get_slot_by_key
HID: logitech-hidpp: fix error return code
HID: wacom: Add support for Cintiq 13HD Touch
HID: logitech-hidpp: add a module parameter to keep firmware gestures
HID: usbhid: yet another mouse with ALWAYS_POLL
HID: usbhid: more mice with ALWAYS_POLL
HID: wacom: set stylus_in_proximity before checking touch_down
HID: wacom: use wacom_wac_finger_count_touches to set touch_down
HID: wacom: remove hardcoded WACOM_QUIRK_MULTI_INPUT
HID: pidff: effect can't be NULL
HID: add quirk for PIXART OEM mouse used by HP
HID: add HP OEM mouse to quirk ALWAYS_POLL
HID: wacom: ask for a in-prox report when it was missed
HID: hid-sensor-hub: Fix sparse warning
HID: hid-sensor-hub: fix attribute read for logical usage id
HID: plantronics: fix Kconfig default
HID: pidff: support more than one concurrent effect
...
Do not call power_supply_powers() if power_supply_register() failed
earlier. This fixes possible NULL pointer dereference by
power_supply_powers() in such case.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Change the ownership of power_supply structure from each driver
implementing the class to the power supply core.
The patch changes power_supply_register() function thus all drivers
implementing power supply class are adjusted.
Each driver provides the implementation of power supply. However it
should not be the owner of power supply class instance because it is
exposed by core to other subsystems with power_supply_get_by_name().
These other subsystems have no knowledge when the driver will unregister
the power supply. This leads to several issues when driver is unbound -
mostly because user of power supply accesses freed memory.
Instead let the core own the instance of struct 'power_supply'. Other
users of this power supply will still access valid memory because it
will be freed when device reference count reaches 0. Currently this
means "it will leak" but power_supply_put() call in next patches will
solve it.
This solves invalid memory references in following race condition
scenario:
Thread 1: charger manager
Thread 2: power supply driver, used by charger manager
THREAD 1 (charger manager) THREAD 2 (power supply driver)
========================== ==============================
psy = power_supply_get_by_name()
Driver unbind, .remove
power_supply_unregister()
Device fully removed
psy->get_property()
The 'get_property' call is executed in invalid context because the driver was
unbound and struct 'power_supply' memory was freed.
This could be observed easily with charger manager driver (here compiled
with max17040 fuel gauge):
$ cat /sys/devices/virtual/power_supply/cm-battery/capacity &
$ echo "1-0036" > /sys/bus/i2c/drivers/max17040/unbind
[ 55.725123] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[ 55.732584] pgd = d98d4000
[ 55.734060] [00000000] *pgd=5afa2831, *pte=00000000, *ppte=00000000
[ 55.740318] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
[ 55.746210] Modules linked in:
[ 55.749259] CPU: 1 PID: 2936 Comm: cat Tainted: G W 3.19.0-rc1-next-20141226-00048-gf79f475f3c44-dirty #1496
[ 55.760190] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[ 55.766270] task: d9b76f00 ti: daf54000 task.ti: daf54000
[ 55.771647] PC is at 0x0
[ 55.774182] LR is at charger_get_property+0x2f4/0x36c
[ 55.779201] pc : [<00000000>] lr : [<c034b0b4>] psr: 60000013
[ 55.779201] sp : daf55e90 ip : 00000003 fp : 00000000
[ 55.790657] r10: 00000000 r9 : c06e2878 r8 : d9b26c68
[ 55.795865] r7 : dad81610 r6 : daec7410 r5 : daf55ebc r4 : 00000000
[ 55.802367] r3 : 00000000 r2 : daf55ebc r1 : 0000002a r0 : d9b26c68
[ 55.808879] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
[ 55.815994] Control: 10c5387d Table: 598d406a DAC: 00000015
[ 55.821723] Process cat (pid: 2936, stack limit = 0xdaf54210)
[ 55.827451] Stack: (0xdaf55e90 to 0xdaf56000)
[ 55.831795] 5e80: 60000013 c01459c4 0000002a c06f8ef8
[ 55.839956] 5ea0: db651000 c06f8ef8 daebac00 c04cb668 daebac08 c0346864 00000000 c01459c4
[ 55.848115] 5ec0: d99eaa80 c06f8ef8 00000fff 00001000 db651000 c027f25c c027f240 d99eaa80
[ 55.856274] 5ee0: d9a06c00 c0146218 daf55f18 00001000 d99eaa80 db4c18c0 00000001 00000001
[ 55.864468] 5f00: daf55f80 c0144c78 c0144c54 c0107f90 00015000 d99eaab0 00000000 00000000
[ 55.872603] 5f20: 000051c7 00000000 db4c18c0 c04a9370 00015000 00001000 daf55f80 00001000
[ 55.880763] 5f40: daf54000 00015000 00000000 c00e53dc db4c18c0 c00e548c 0000000d 00008124
[ 55.888937] 5f60: 00000001 00000000 00000000 db4c18c0 db4c18c0 00001000 00015000 c00e5550
[ 55.897099] 5f80: 00000000 00000000 00001000 00001000 00015000 00000003 00000003 c000f364
[ 55.905239] 5fa0: 00000000 c000f1a0 00001000 00015000 00000003 00015000 00001000 0001333c
[ 55.913399] 5fc0: 00001000 00015000 00000003 00000003 00000002 00000000 00000000 00000000
[ 55.921560] 5fe0: 7fffe000 be999850 0000a225 b6f3c19c 60000010 00000003 00000000 00000000
[ 55.929744] [<c034b0b4>] (charger_get_property) from [<c0346864>] (power_supply_show_property+0x48/0x20c)
[ 55.939286] [<c0346864>] (power_supply_show_property) from [<c027f25c>] (dev_attr_show+0x1c/0x48)
[ 55.948130] [<c027f25c>] (dev_attr_show) from [<c0146218>] (sysfs_kf_seq_show+0x84/0x104)
[ 55.956298] [<c0146218>] (sysfs_kf_seq_show) from [<c0144c78>] (kernfs_seq_show+0x24/0x28)
[ 55.964536] [<c0144c78>] (kernfs_seq_show) from [<c0107f90>] (seq_read+0x1b0/0x484)
[ 55.972172] [<c0107f90>] (seq_read) from [<c00e53dc>] (__vfs_read+0x18/0x4c)
[ 55.979188] [<c00e53dc>] (__vfs_read) from [<c00e548c>] (vfs_read+0x7c/0x100)
[ 55.986304] [<c00e548c>] (vfs_read) from [<c00e5550>] (SyS_read+0x40/0x8c)
[ 55.993164] [<c00e5550>] (SyS_read) from [<c000f1a0>] (ret_fast_syscall+0x0/0x48)
[ 56.000626] Code: bad PC value
[ 56.011652] ---[ end trace 7b64343fbdae8ef1 ]---
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
[for the nvec part]
Reviewed-by: Marc Dietrich <marvin24@gmx.de>
[for compal-laptop.c]
Acked-by: Darren Hart <dvhart@linux.intel.com>
[for the mfd part]
Acked-by: Lee Jones <lee.jones@linaro.org>
[for the hid part]
Acked-by: Jiri Kosina <jkosina@suse.cz>
[for the acpi part]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Add new structure 'power_supply_config' for holding run-time
initialization data like of_node, supplies and private driver data.
The power_supply_register() function is changed so all power supply
drivers need updating.
When registering the power supply this new 'power_supply_config' should be
used instead of directly initializing 'struct power_supply'. This allows
changing the ownership of power_supply structure from driver to the
power supply core in next patches.
When a driver does not use of_node or supplies then it should use NULL
as config. If driver uses of_node or supplies then it should allocate
config on stack and initialize it with proper values.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
[for the nvec part]
Reviewed-by: Marc Dietrich <marvin24@gmx.de>
[for drivers/platform/x86/compal-laptop.c]
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
[for drivers/hid/*]
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Currently HID code maps usages from telephony page into BTN_0, BTN_1, etc
keys which get interpreted by mousedev and userspace as left/right/middle
button clicks, which is not really helpful.
This change adds mappings for usages that have corresponding input event
definitions, and leaves the rest unmapped. This can be changed when
there are userspace consumers for more telephony usages.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The ignore check that got added in 6ce901eb61 ("HID: input: fix confusion
on conflicting mappings") needs to properly check for VARIABLE reports
as well (ARRAY reports should be ignored), otherwise legitimate keyboards
might break.
Cc: <stable@vger.kernel.org>
Fixes: 6ce901eb61 ("HID: input: fix confusion on conflicting mappings")
Reported-by: Fredrik Hallenberg <megahallon@gmail.com>
Reported-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
On an PC-101/103/104 keyboard (American layout) the 'Enter' key and its
neighbours look like this:
+---+ +---+ +-------+
| 1 | | 2 | | 5 |
+---+ +---+ +-------+
+---+ +-----------+
| 3 | | 4 |
+---+ +-----------+
On a PC-102/105 keyboard (European layout) it looks like this:
+---+ +---+ +-------+
| 1 | | 2 | | |
+---+ +---+ +-+ 4 |
+---+ +---+ | |
| 3 | | 5 | | |
+---+ +---+ +-----+
(Note that the number of keys is the same, but key '5' is moved down and
the shape of key '4' is changed. Keys '1' to '3' are exactly the same.)
The keys 1-4 report the same scan-code in HID in both layouts, even though
the keysym they produce is usually different depending on the XKB-keymap
used by user-space.
However, key '5' (US 'backslash'/'pipe') reports 0x31 for the upper layout
and 0x32 for the lower layout, as defined by the HID spec. This is highly
confusing as the linux-input API uses a single keycode for both.
So far, this was never a problem as there never has been a keyboard with
both of those keys present at the same time. It would have to look
something like this:
+---+ +---+ +-------+
| 1 | | 2 | | x31 |
+---+ +---+ +-------+
+---+ +---+ +-----+
| 3 | |x32| | 4 |
+---+ +---+ +-----+
HID can represent such a keyboard, but the linux-input API cannot.
Furthermore, any user-space mapping would be confused by this and,
luckily, no-one ever produced such hardware.
Now, the HID input layer fixed this mess by mapping both 0x31 and 0x32 to
the same keycode (KEY_BACKSLASH==0x2b). As only one of both physical keys
is present on a hardware, this works just fine.
Lets introduce hardware-vendors into this:
------------------------------------------
Unfortunately, it seems way to expensive to produce a different device for
American and European layouts. Therefore, hardware-vendors put both keys,
(0x31 and 0x32) on the same keyboard, but only one of them is hooked up
to the physical button, the other one is 'dead'.
This means, they can use the same hardware, with a different button-layout
and automatically produce the correct HID events for American *and*
European layouts. This is unproblematic for normal keyboards, as the
'dead' key will never report any KEY-DOWN events. But RollOver keyboards
send the whole matrix on each key-event, allowing n-key roll-over mode.
This means, we get a 0x31 and 0x32 event on each key-press. One of them
will always be 0, the other reports the real state. As we map both to the
same keycode, we will get spurious key-events, even though the real
key-state never changed.
The easiest way would be to blacklist 'dead' keys and never handle those.
We could simply read the 'country' tag of USB devices and blacklist either
key according to the layout. But... hardware vendors... want the same
device for all countries and thus many of them set 'country' to 0 for all
devices. Meh..
So we have to deal with this properly. As we cannot know which of the keys
is 'dead', we either need a heuristic and track those keys, or we simply
make use of our value-tracking for HID fields. We simply ignore HID events
for absolute data if the data didn't change. As HID tracks events on the
HID level, we haven't done the keycode translation, yet. Therefore, the
'dead' key is tracked independently of the real key, therefore, any events
on it will be ignored.
This patch simply discards any HID events for absolute data if it didn't
change compared to the last report. We need to ignore relative and
buffered-byte reports for obvious reasons. But those cannot be affected by
this bug, so we're fine.
Preferably, we'd do this filtering on the HID-core level. But this might
break a lot of custom drivers, if they do not follow the HID specs.
Therefore, we do this late in hid-input just before we inject it into the
input layer (which does the exact same filtering, but on the keycode
level).
If this turns out to break some devices, we might have to limit filtering
to EV_KEY events. But lets try to do the Right Thing first, and properly
filter any absolute data that didn't change.
This patch is tagged for 'stable' as it fixes a lot of n-key RollOver
hardware. We might wanna wait with backporting for a while, before we know
it doesn't break anything else, though.
Cc: <stable@vger.kernel.org>
Reported-by: Adam Goode <adam@spicenitz.org>
Reported-by: Fredrik Hallenberg <megahallon@gmail.com>
Tested-by: Fredrik Hallenberg <megahallon@gmail.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Apple bluetooth wireless keyboard (sold in UK) has always reported zero
for battery strength no matter what condition the batteries are actually
in. With this patch applied (applying same quirk as other Apple
keyboards), the battery strength is now correctly reported.
Signed-off-by: Karl Relton <karllinuxtest.relton@ntlworld.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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>
The commit which introduced TransducerSerialNumber (368c966) is missing
two crucial implementation details. Firstly, the commit does not set the
type/code/bit/max fields as expected later down the code which can cause
the driver to crash when a tablet with this usage is connected. Secondly,
the call to 'set_bit' causes MSC_PULSELED to be sent instead of the
expected MSC_SERIAL. This commit addreses both issues.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Currently unknown consumer page codes are ignored, which means that they cannot
later be mapped from userspace using udev / hwdb. Map them to KEY_UNKNOWN, so
that userspace can remap them for keyboards which make up their own consumer
page codes.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Atmel 840B digitizer presents a stylus interface which reports twice
the X coordinate and then twice the Y coordinate. In its current
implementation, hid-input assign the first X to X, then the second to Y,
then the first Y to Z, then the second one to RX.
This is wrong, and X should always be mapped to X, no matter what.
A solution consists in forcing X, Y, Z, RX, RY, RZ to be mapped to their
correct user space counter part.
Reported-by: Éric Brunet <Eric.Brunet@lps.ens.fr>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
On Feb 17, 2014, two new usages are approved to HID usage Table 18 -
Digitizer Page:
5A Secondary Barrel Switch MC 16.4
5B Transducer Serial Number SV 16.3.1
This patch adds relevant definitions to hid/input. It also removes
outdated comments in hid.h.
Signed-off-by: Ping Cheng <pingc@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
SET_REPORT and GET_REPORT are mandatory in the HID specification.
Make the corresponding API in hid-core mandatory too, which removes the
need to test against it in some various places.
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>
hid_output_raw_report() is not a ll_driver callback and should not be used.
To keep the same code path than before, we are forced to play with the
different hid_hw_* calls: if the usb or i2c device does not support
direct output reports, then we will rely on the SET_REPORT HID call.
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>
Add a helper to access hdev->hid_output_raw_report().
To convert the drivers, use the following snippets:
for i in drivers/hid/*.c
do
sed -i.bak "s/[^ \t]*->hid_output_raw_report(/hid_output_raw_report(/g" $i
done
Then manually fix for checkpatch.pl
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>
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>
All the different transport drivers use now the generic event handling
in hid-input. We can remove the handler definitively now.
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 mapping for "AL Next Task/Application", "AL Previous Task/Application"
and "AL File Browser" buttons, as found on the Microsoft Office keyboard.
Note that there already is a mapping for "AL Local Machine Browser" to
KEY_FILE. Unless we ever encounter a device with both that should not be
a problem.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
When using hid_output_report(), the buffer should be allocated by hid_alloc_report_buf(),
not a custom malloc.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
we used to set the parent of the input device as the parent of
the hid bus. This was introduced when we created hid as a real bus, and
to keep backward compatibility. Now, it's time to proper set the parent
so that sysfs has an idea of which input device is attached to
which hid device.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Revert some changes done in 7746383868.
Revert all changes done in hidinput_calc_abs_res as it mistakingly used
"Unit" item exponent nibbles to affect resolution value. This wasn't
breaking resolution calculation of relevant axes of any existing
devices, though, as they have only one dimension to their units and thus
1 in the corresponding nible.
Revert to reading "Unit Exponent" item value as a signed integer in
hid_parser_global to fix reading specification-complying values. This
fixes resolution calculation of devices complying to the HID standard,
including Huion, KYE, Waltop and UC-Logic graphics tablets which have
their report descriptors fixed by the drivers.
Explanations follow.
There are two "unit exponents" in HID specification and it is important
not to mix them. One is the global "Unit Exponent" item and another is
nibble values in the global "Unit" item. See 6.2.2.7 Global Items.
The "Unit Exponent" value is just a signed integer and is used to scale
the integer resolution unit values, so fractions can be expressed.
The nibbles of "Unit" value are used to select the unit system (nibble
0), and presence of a particular basic unit type in the unit formula and
its *exponent* (or power, nibbles 1-6). And yes, the latter is in two
complement and zero means absence of the unit type.
Taking the representation example of (integer) joules from the
specification:
[mass(grams)][length(centimeters)^2][time(seconds)^-2] * 10^-7
the "Unit Exponent" would be -7 (or 0xF9, if stored as a byte) and the
"Unit" value would be 0xE121, signifying:
Nibble Part Value Meaning
----- ---- ----- -------
0 System 1 SI Linear
1 Length 2 Centimeters^2
2 Mass 1 Grams
3 Time -2 Seconds^-2
To give the resolution in e.g. hundredth of joules the "Unit Exponent"
item value should have been -9.
See also the examples of "Unit" values for some common units in the same
chapter.
However, there is a common misunderstanding about the "Unit Exponent"
value encoding, where it is assumed to be stored the same as nibbles in
"Unit" item. This is most likely due to the specification being a bit
vague and overloading the term "unit exponent". This also was and still
is proliferated by the official "HID Descriptor Tool", which makes this
mistake and stores "Unit Exponent" as such. This format is also
mentioned in books such as "USB Complete" and in Microsoft's hardware
design guides.
As a result many devices currently on the market use this encoding and
so the driver should support them.
Signed-off-by: Nikolai Kondrashov <spbnick@gmail.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
When dealing with usage_index, be sure to properly use unsigned instead of
int to avoid overflows.
When working on report fields, always validate that their report_counts are
in bounds.
Without this, a HID device could report a malicious feature report that
could trick the driver into a heap overflow:
[ 634.885003] usb 1-1: New USB device found, idVendor=0596, idProduct=0500
...
[ 676.469629] BUG kmalloc-192 (Tainted: G W ): Redzone overwritten
CVE-2013-2897
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Instead of using data from stack for DMA in hidinput_get_battery_property(),
allocate the buffer dynamically.
Cc: stable@kernel.org
Reported-by: Richard Ryniker <ryniker@alum.mit.edu>
Reported-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The hidinput_input_event() callback converts input events written from
userspace into HID reports and sends them to the device. We currently
implement this in every HID transport driver, even though most of them do
the same.
This provides a generic hidinput_input_event() implementation which is
mostly copied from usbhid. It uses a delayed worker to allow multiple LED
events to be collected into a single output event.
We use the custom ->request() transport driver callback to allow drivers
to adjust the outgoing report and handle the request asynchronously. If no
custom ->request() callback is available, we fall back to the generic raw
output report handler (which is synchronous).
Drivers can still provide custom hidinput_input_event() handlers (see
logitech-dj) if the generic implementation doesn't fit their needs.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Extend the comment explaining the condition for discarding
out-of-range values to clarify the cases in which devices don't
provide any logical min/max.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Commit 6da7066906 introduced in 3.3
"HID: ignore absolute values which don't fit between logical min and max"
prevents some Posiflex touch screen to work because they do not provide
logical min and max for their buttons.
Thus, logical min and max are at 0, discarding the buttons events, and
preventing the device to report appropriate X Y.
Adding a check on "min < max" solves the problem.
Reported-by: Jan Kandziora <jjj@gmx.de>
Tested-by: Jan Kandziora <jjj@gmx.de>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
power_supply core has the bad habit of calling our battery callbacks
from within power_supply_register(). Furthermore, if the callbacks
fail with an unhandled error code, it will skip any uevent that it
might currently process.
So if HID-core registers battery devices, an "add" uevent is generated
and the battery callbacks are called. These will gracefully fail due
to timeouts as they might still hold locks on event processing. One
could argue that this should be fixed in power_supply core, but the
least we can do is to signal ENODATA so power_supply core will just
skip the property and continue with the uevent.
This fixes a bug where "add" and "remove" uevents are skipped for
battery devices. upower is unable to track these devices and currently
needs to ignore them.
This patch also overwrites any other error code. I cannot see any reason
why we should forward protocol- or I/O-errors to the power_supply core.
We handle these errors in hid_ll_driver later, anyway, so just skip
them. power_supply core cannot do anything useful with them, anyway,
and we avoid skipping important uevents and confusing user-space.
Thanks a lot to Daniel Nicoletti for pushing and investigating
on this.
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Reported-by: Daniel Nicoletti <dantti12@gmail.com>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
There is no need to register an input device containing no events.
This allows drivers using the quirk MULTI_INPUT to register one input
per report effectively used.
For backward compatibility, we need to add a quirk to request
this behavior.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This just refactors the allocation of hid_input.
No semantic changes.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
HID spec details special values for the HID field unit exponent.
Basically, the range [0x8..0xf] correspond to [-8..-1], so this is
a standard two's complement on a half-byte.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
hidinput_calc_abs_res should return the closest int in the division
instead of the floor.
On a device with a logical_max of 3008 and a physical_max of 255mm,
previous implementation gave a resolution of 11 instead of 12.
With 11, user-space computes a physical size of 273.5mm and the
round_closest results gives 250.6mm.
The old implementation introduced an error of 2cm in this example.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Jiri Kosina