Make use of the new enable_gpio field and allow it to be set from DT as
well. Now that all legacy users of platform data have been converted to
initialize this field to an invalid value, it is safe to use the field
from the driver.
Signed-off-by: Thierry Reding <treding@nvidia.com>
The GPIO API defines 0 as being a valid GPIO number, so this field needs
to be initialized explicitly.
Signed-off-by: Thierry Reding <treding@nvidia.com>
The GPIO API defines 0 as being a valid GPIO number, so this field needs
to be initialized explicitly.
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The GPIO API defines 0 as being a valid GPIO number, so this field needs
to be initialized explicitly.
Signed-off-by: Thierry Reding <treding@nvidia.com>
The GPIO API defines 0 as being a valid GPIO number, so this field needs
to be initialized explicitly.
A special case is the Palm Tungsten|C board. Since it doesn't use any
quirks that would require the existing .init() or .exit() hooks it can
simply use the new enable_gpio field.
Signed-off-by: Thierry Reding <treding@nvidia.com>
The GPIO API defines 0 as being a valid GPIO number, so this field needs
to be initialized explicitly.
Signed-off-by: Thierry Reding <treding@nvidia.com>
To support a wider variety of backlight setups, introduce an optional
enable GPIO. Legacy users of the platform data already have a means of
supporting GPIOs by using the .init(), .exit() and .notify() hooks. DT
users however cannot use those, so an alternative method is required.
In order to ease the introduction of the optional enable GPIO, make it
available in the platform data first, so that existing users can be
converted. Once that has happened a second patch will add code to make
use of it in the driver.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Follow up patches will add support for more complex means of powering
the backlight on and off such as using a regulator. To prevent calls to
the regulator API from becoming unbalanced, keep track of the enabled
state internally.
Signed-off-by: Thierry Reding <treding@nvidia.com>
In preparation for adding an optional regulator and enable GPIO to the
driver, split the power on and power off sequences into separate
functions to reduce code duplication at the multiple call sites.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Add more blank lines to increase readability. While at it, remove a
trailing blank line at the end of the file.
Signed-off-by: Thierry Reding <treding@nvidia.com>
This will stop UPower from detecting the tablet as a power supply,
and using its battery status to hibernate or switch off the machine.
https://bugs.freedesktop.org/show_bug.cgi?id=70321
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Add the missing clk_disable_unprepare() before return
from nspire_keypad_open() in the error handling case.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
It wasn't really clear from the gamepad-API description how ABS values are
mapped exactly. Clarify that negative is left/up and positive is
right/down. Unfortunately, this means I screwed up the Wii U ProController
ABI. Anyhow, this just means we continue to have 0 compatible gamepad
drivers in the kernel. User-space needs to fix them up, anyway, as all
other gamepads are also incompatible.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Commit:
65cd4f6 ("arch_timer: Move to generic sched_clock framework")
added code to register the arch_sys_counter in arch_timer_register(),
but it is already registered in arch_counter_register().
This results in the timer being added to the clocksource list twice,
therefore causing an infinite loop in the list.
Remove the duplicate registration and register the scheduler
clock after the original registration instead.
This fixes a hang during boot on Tegra114 (Cortex-A15).
[ While I've only tested this on Tegra114, I suspect the same hang
during boot happens for all processors that use this clock source. ]
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: http://lkml.kernel.org/r/1381843911-31962-1-git-send-email-treding@nvidia.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes a particular type of data corruption that has been
encountered when loading a snapshot's metadata from disk.
When we allocate a new chunk in persistent_prepare, we increment
ps->next_free and we make sure that it doesn't point to a metadata area
by further incrementing it if necessary.
When we load metadata from disk on device activation, ps->next_free is
positioned after the last used data chunk. However, if this last used
data chunk is followed by a metadata area, ps->next_free is positioned
erroneously to the metadata area. A newly-allocated chunk is placed at
the same location as the metadata area, resulting in data or metadata
corruption.
This patch changes the code so that ps->next_free skips the metadata
area when metadata are loaded in function read_exceptions.
The patch also moves a piece of code from persistent_prepare_exception
to a separate function skip_metadata to avoid code duplication.
CVE-2013-4299
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Cc: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Update comments to reflect what is really going on and add the TWE bit
to the comments in kvm_arm.h.
Also renames the function to kvm_handle_wfx like is done on arm64 for
consistency and uber-correctness.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
On an (even slightly) oversubscribed system, spinlocks are quickly
becoming a bottleneck, as some vcpus are spinning, waiting for a
lock to be released, while the vcpu holding the lock may not be
running at all.
This creates contention, and the observed slowdown is 40x for
hackbench. No, this isn't a typo.
The solution is to trap blocking WFEs and tell KVM that we're
now spinning. This ensures that other vpus will get a scheduling
boost, allowing the lock to be released more quickly. Also, using
CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT slightly improves the performance
when the VM is severely overcommited.
Quick test to estimate the performance: hackbench 1 process 1000
2xA15 host (baseline): 1.843s
2xA15 guest w/o patch: 2.083s
4xA15 guest w/o patch: 80.212s
8xA15 guest w/o patch: Could not be bothered to find out
2xA15 guest w/ patch: 2.102s
4xA15 guest w/ patch: 3.205s
8xA15 guest w/ patch: 6.887s
So we go from a 40x degradation to 1.5x in the 2x overcommit case,
which is vaguely more acceptable.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
BugLink: http://bugs.launchpad.net/bugs/1235977
The profile introspection seq file has a locking bug when policy is viewed
from a virtual root (task in a policy namespace), introspection from the
real root is not affected.
The test for root
while (parent) {
is correct for the real root, but incorrect for tasks in a policy namespace.
This allows the task to walk backup the policy tree past its virtual root
causing it to be unlocked before the virtual root should be in the p_stop
fn.
This results in the following lockdep back trace:
[ 78.479744] [ BUG: bad unlock balance detected! ]
[ 78.479792] 3.11.0-11-generic #17 Not tainted
[ 78.479838] -------------------------------------
[ 78.479885] grep/2223 is trying to release lock (&ns->lock) at:
[ 78.479952] [<ffffffff817bf3be>] mutex_unlock+0xe/0x10
[ 78.480002] but there are no more locks to release!
[ 78.480037]
[ 78.480037] other info that might help us debug this:
[ 78.480037] 1 lock held by grep/2223:
[ 78.480037] #0: (&p->lock){+.+.+.}, at: [<ffffffff812111bd>] seq_read+0x3d/0x3d0
[ 78.480037]
[ 78.480037] stack backtrace:
[ 78.480037] CPU: 0 PID: 2223 Comm: grep Not tainted 3.11.0-11-generic #17
[ 78.480037] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 78.480037] ffffffff817bf3be ffff880007763d60 ffffffff817b97ef ffff8800189d2190
[ 78.480037] ffff880007763d88 ffffffff810e1c6e ffff88001f044730 ffff8800189d2190
[ 78.480037] ffffffff817bf3be ffff880007763e00 ffffffff810e5bd6 0000000724fe56b7
[ 78.480037] Call Trace:
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff817b97ef>] dump_stack+0x54/0x74
[ 78.480037] [<ffffffff810e1c6e>] print_unlock_imbalance_bug+0xee/0x100
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff810e5bd6>] lock_release_non_nested+0x226/0x300
[ 78.480037] [<ffffffff817bf2fe>] ? __mutex_unlock_slowpath+0xce/0x180
[ 78.480037] [<ffffffff817bf3be>] ? mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff810e5d5c>] lock_release+0xac/0x310
[ 78.480037] [<ffffffff817bf2b3>] __mutex_unlock_slowpath+0x83/0x180
[ 78.480037] [<ffffffff817bf3be>] mutex_unlock+0xe/0x10
[ 78.480037] [<ffffffff81376c91>] p_stop+0x51/0x90
[ 78.480037] [<ffffffff81211408>] seq_read+0x288/0x3d0
[ 78.480037] [<ffffffff811e9d9e>] vfs_read+0x9e/0x170
[ 78.480037] [<ffffffff811ea8cc>] SyS_read+0x4c/0xa0
[ 78.480037] [<ffffffff817ccc9d>] system_call_fastpath+0x1a/0x1f
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Some strange character leaped into the documentation, which makes
git-send-email behave quite strangely. Get rid of this before it bites
anyone else.
Cc: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
One bug fix and three reverts. The reverts back out the slightly
controversial feeding the entire device tree into the random pool and
the reserved-memory binding which isn't fully baked yet. Expect the
reserved-memory patches at least to resurface for v3.13. The bug fixes
removes a scary but harmless warning on SPARC that was introduced in the
v3.12 merge window. v3.13 will contain a proper fix that makes the new
code work on SPARC.
On the plus side, the diffstat looks *awesome*. I love removing lines of code.
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Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux
Pull device tree fixes and reverts from Grant Likely:
"One bug fix and three reverts. The reverts back out the slightly
controversial feeding the entire device tree into the random pool and
the reserved-memory binding which isn't fully baked yet. Expect the
reserved-memory patches at least to resurface for v3.13.
The bug fixes removes a scary but harmless warning on SPARC that was
introduced in the v3.12 merge window. v3.13 will contain a proper fix
that makes the new code work on SPARC.
On the plus side, the diffstat looks *awesome*. I love removing lines
of code"
* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux:
Revert "drivers: of: add initialization code for dma reserved memory"
Revert "ARM: init: add support for reserved memory defined by device tree"
Revert "of: Feed entire flattened device tree into the random pool"
of: fix unnecessary warning on missing /cpus node
Pull DMA-mapping fix from Marek Szyprowski:
"A bugfix for the IOMMU-based implementation of dma-mapping subsystem
for ARM architecture"
* 'fixes-for-v3.12' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
ARM: dma-mapping: Always pass proper prot flags to iommu_map()
For devices which don't have a .runtime_idle() callback or if it
returns 0, rpm_idle() will end up in triggering a call to
rpm_suspend(), thus trying to carry out a runtime suspend directly
from runtime_idle().
In the above situation we want to respect devices which has enabled
autosuspend, we therfore append the flag sent to rpm_suspend with
RPM_AUTO.
Do note that drivers still needs to update the device last busy mark,
to control the delay for this circumstance.
Updated runtime PM documentation accordingly.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The return value of mgmt_new_ltk() function is not used and
so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_read_local_oob_data_reply_complete() function
is not used and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_set_local_name_complete() function is
not used and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_set_class_of_dev_complete() function is
not used and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_ssp_enable_complete() function is not
used and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_auth_enable_complete() function is not
used and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_auth_failed() function is not used
and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_pin_code_neg_reply_complete() function is
not used and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_pin_code_reply_complete() function is not
used and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
The return value of mgmt_pin_code_request() function is not used
and so just change it to return void.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
In this case the replacement by l2cap_chan_ready() doesn't change the code
flow, the same operations will executed plus two others that have no
effect: the use of the parent socket, that a non-oriented channel doesn't
have and the reset of conf_state, which is also fine since the connection
is ready at this point.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The wait_ack code has a heavy dependency on the socket data structures
and, as of now, it won't be worthless change it to use non-socket
structures as the only user of such feature is a socket.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
We need to remove all direct access of struct sock from L2CAP core.
This change is pretty simple and just add a new L2CAP channel callback to
do the work in the L2CAP socket side.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
As part of the work to remove struct sock from l2cap_core.c and make it
more generic we remove in this commit the direct access to sk->sk_sndtimeo
member. This objective of this change is purely remove sk usage from
l2cap_core.c
Now we have a new l2cap ops to get the current value of sk->sndtimeo. A
l2cap_chan_no_get_sndtimeo was added for users of L2CAP that doesn't need
to set a timeout.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
l2cap_state_change_and_error() introduces the ability to update a
l2cap_user with changes in channel's state and error code with just one
call. The main reason for this is to avoid race conditions between and
setting the state and then the error. Otherwise we would need to release
the lock between both operations.
This is another step of an ongoing work to make l2cap_core.c totally
independent from l2cap's struct sock.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Instead of creating an new function pointer to report errors we are just
reusing state_change for that and there is a simple reason for this, one
place in the l2cap_core.c code needs, in a locked sk, set both the sk_state
and sk_err. If we create two different functions for this we would need to
release the lock between the two operation putting the socket in non
desired state.
The change is transparent to the l2cap_core.c code, user that only needs
to set the state won't need any modification.
This is another step of an ongoing work to make l2cap_core.c totally
independent from l2cap's struct sock.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the system is suspended while max_perf_pct is less than 100 percent
or no_turbo set policy->{min,max} will be set incorrectly with scaled
values which turn the scaled values into hard limits.
References: https://bugzilla.kernel.org/show_bug.cgi?id=61241
Reported-by: Patrick Bartels <petzicus@googlemail.com>
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On the Yoga 13 the backlight control doesn't work via ACPI. (And doesn't
work either with the low-level platform driver ideapad_laptop; but
works correctly via the intel video driver). This patch hence adds the
Yoga 13 to the ACPI video detect blacklist, to make sure the broken ACPI
backlight device is never exposed to userspace.
Note that this appears unrelated to the Windows 8 backlight issues tracked
here:
https://bugzilla.kernel.org/show_bug.cgi?id=51231https://bugzilla.kernel.org/show_bug.cgi?id=60682
The Yoga's ACPI backlight controls work neither with nor without
acpi_osi="!Windows 2012" on the kernel command line. It appears that
backlight control via the EC simply is not available at all, regardless
whether done via ACPI or via the vendor driver.
Signed-off-by: Lennart Poettering <lennart@poettering.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
AC's proc directory is not used and so remove it. Prepare for removing
/proc/acpi directory.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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Merge tag 'stable/for-linus-3.12-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull Xen fixes from Stefano Stabellini:
"A small fix for Xen on x86_32 and a build fix for xen-tpmfront on
arm64"
* tag 'stable/for-linus-3.12-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: Fix possible user space selector corruption
tpm: xen-tpmfront: fix missing declaration of xen_domain
The tpacpi_acpi_handle_locate function makes use of acpi_get_devices to
locate handle for ACPI video by HID, the problem is, ACPI video node
doesn't really have HID defined(i.e. no _HID control method is defined
for video device), so.. that function would fail. This can be solved by
enhancing the callback function for acpi_get_devices, where we can use
acpi_device_hid function to check if the ACPI node corresponds to a
video controller.
In addition to that, the _BCL control method only exists under a video
output device node, not a video controller device node. So to evaluate
_BCL, we need the handle of a video output device node, which is child
of the located video controller node from tpacpi_acpi_handle_locate.
The two fix are necessary for some Thinkpad models to emit notification
on backlight hotkey press as a result of evaluation of _BCL.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to Matthew Garrett, "Windows 8 leaves backlight control up
to individual graphics drivers rather than making ACPI calls itself.
There's plenty of evidence to suggest that the Intel driver for
Windows [8] doesn't use the ACPI interface, including the fact that
it's broken on a bunch of machines when the OS claims to support
Windows 8. The simplest thing to do appears to be to disable the
ACPI backlight interface on these systems".
So for Win8 systems, if there is native backlight control interface
registered by GPU driver, ACPI video does not need to register its own.
Since there are systems that don't work well with this approach, a
parameter for video module named use_native_backlight is introduced and
has the value of false by default. For users who have a broken ACPI
video backlight interface, video.use_native_backlight=1 is needed in
kernel cmdline.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The backlight control and event delivery functionality provided by ACPI
video module is mixed together and registered all during video device
enumeration time. As a result, the two functionality are also removed
together on module unload time or by the acpi_video_unregister function.
The two functionalities are actually independent and one may be useful
while the other one may be broken, so it is desirable to seperate the
two functionalities such that it is clear and easy to disable one
functionality without affecting the other one.
APIs to selectively remove backlight control interface and/or event
delivery functionality can be easily added once needed.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce a new API for modules to query if a specific type of backlight
device has been registered. This is useful for some backlight device
provider module (e.g. ACPI video) to know if a native control
interface(e.g. the interface created by i915) is available and then do
things accordingly (e.g. avoid registering its own on Win8 systems).
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
