Trying to support both the switcher and CPU hotplug at the same time
is tricky due to ambiguous semantics.  So let's at least prevent users
from messing around with those logical CPUs the switcher has removed
and those which were not active when the switcher was activated.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

Up to now, the logical CPU was somehow tied to the physical CPU number
within a cluster.  This causes problems when forcing the boot CPU to be
different from the first enumerated CPU in the device tree creating a
discrepancy between logical and physical CPU numbers.

Let's make the pairing completely independent from physical CPU numbers.

Let's keep only those logical CPUs with same initial CPU cluster to create
a uniform scheduler profile without having to modify any of the probed
topology and compute capacity data.  This has the potential to create
a non contiguous CPU numbering space when the switcher is active with
potential impact on buggy user space tools.  It is however better to fix
those tools rather than making the switcher code more intrusive.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

By adding no_bL_switcher to the kernel cmdline string, the switcher
won't be activated automatically at boot time.  It is still possible
to activate it later with:

	echo 1 > /sys/kernel/bL_switcher/active
Signed-off-by: Nicolas Pitre <nico@linaro.org>

The /sys/kernel/bL_switcher/enable file allows to enable or disable
the switcher by writing 1 or 0 to it respectively.  It is still enabled
by default on boot.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

Currently, GIC IDs are hardcoded making the code dependent on the 4+4 b.L
configuration.  Let's allow for GIC IDs to be discovered upon switcher
initialization to support other b.L configurations such as the 1+1 one,
or 2+3 as on the VExpress TC2.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

In a regular kernel configuration, all the CPUs are initially available.
But the switcher execution model uses half of them at any time.  Instead
of hacking the DTB to remove half of the CPUs, let's remove them at
run time and make sure we still have a working switcher configuration.
This way, the same DTB can be used whether or not the switcher is used.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

We now have a dedicated thread for each logical CPU.  That's plenty
of stack space for our needs.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

The workqueues are problematic as they may be contended.
They can't be scheduled with top priority either.  Also the optimization
in bL_switch_request() to skip the workqueue entirely when the target CPU
and the calling CPU were the same didn't allow for bL_switch_request() to
be called from atomic context, as might be the case for some cpufreq
drivers.

Let's move to dedicated kthreads instead.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

Per-CPU timers that are shutdown when a CPU is switched over must be disabled
upon switching and reprogrammed on the inbound CPU by relying on the
clock events management API. save/restore sequence is executed with irqs
disabled as mandated by the clock events API.

The next_event is an absolute time, hence, when the inbound CPU resumes,
if the timer has expired the min delta is forced into the tick device to
fire after few cycles.

This patch adds switching support for clock events that are per-CPU and
have to be migrated when a switch takes place; the cpumask of the clock
event device is checked against the cpumask of the current cpu, and if
they match, the clockevent device mode is saved and it is put in
shutdown mode. Resume code reprogrammes the tick device accordingly.

Tested on A15/A7 fast models and architected timers.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Nicolas Pitre <nico@linaro.org>

This is the core code implementing big.LITTLE switcher functionality.
Rationale for this code is available here:

http://lwn.net/Articles/481055/

The main entry point for a switch request is:

void bL_switch_request(unsigned int cpu, unsigned int new_cluster_id)

If the calling CPU is not the wanted one, this wrapper takes care of
sending the request to the appropriate CPU with schedule_work_on().

At the moment the core switch operation is handled by bL_switch_to()
which must be called on the CPU for which a switch is requested.

What this code does:

  * Return early if the current cluster is the wanted one.

  * Close the gate in the kernel entry vector for both the inbound
    and outbound CPUs.

  * Wake up the inbound CPU so it can perform its reset sequence in
    parallel up to the kernel entry vector gate.

  * Migrate all interrupts in the GIC targeting the outbound CPU
    interface to the inbound CPU interface, including SGIs. This is
    performed by gic_migrate_target() in drivers/irqchip/irq-gic.c.

  * Call cpu_pm_enter() which takes care of flushing the VFP state to
    RAM and save the CPU interface config from the GIC to RAM.

  * Modify the cpu_logical_map to refer to the inbound physical CPU.

  * Call cpu_suspend() which saves the CPU state (general purpose
    registers, page table address) onto the stack and store the
    resulting stack pointer in an array indexed by the updated
    cpu_logical_map, then call the provided shutdown function.
    This happens in arch/arm/kernel/sleep.S.

At this point, the provided shutdown function executed by the outbound
CPU ungates the inbound CPU. Therefore the inbound CPU:

  * Picks up the saved stack pointer in the array indexed by its MPIDR
    in arch/arm/kernel/sleep.S.

  * The MMU and caches are re-enabled using the saved state on the
    provided stack, just like if this was a resume operation from a
    suspended state.

  * Then cpu_suspend() returns, although this is on the inbound CPU
    rather than the outbound CPU which called it initially.

  * The function cpu_pm_exit() is called which effect is to restore the
    CPU interface state in the GIC using the state previously saved by
    the outbound CPU.

  * Exit of bL_switch_to() to resume normal kernel execution on the
    new CPU.

However, the outbound CPU is potentially still running in parallel while
the inbound CPU is resuming normal kernel execution, hence we need
per CPU stack isolation to execute bL_do_switch().  After the outbound
CPU has ungated the inbound CPU, it calls mcpm_cpu_power_down() to:

  * Clean its L1 cache.

  * If it is the last CPU still alive in its cluster (last man standing),
    it also cleans its L2 cache and disables cache snooping from the other
    cluster.

  * Power down the CPU (or whole cluster).

Code called from bL_do_switch() might end up referencing 'current' for
some reasons.  However, 'current' is derived from the stack pointer.
With any arbitrary stack, the returned value for 'current' and any
dereferenced values through it are just random garbage which may lead to
segmentation faults.

The active page table during the execution of bL_do_switch() is also a
problem.  There is no guarantee that the inbound CPU won't destroy the
corresponding task which would free the attached page table while the
outbound CPU is still running and relying on it.

To solve both issues, we borrow some of the task space belonging to
the init/idle task which, by its nature, is lightly used and therefore
is unlikely to clash with our usage.  The init task is also never going
away.

Right now the logical CPU number is assumed to be equivalent to the
physical CPU number within each cluster. The kernel should also be
booted with only one cluster active.  These limitations will be lifted
eventually.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

This is required by the big.LITTLE switcher code.

The gic_migrate_target() changes the CPU interface mapping for the
current CPU to redirect SGIs to the specified interface, and it also
updates the target CPU for each interrupts to that CPU interface
if they were targeting the current interface.  Finally, pending
SGIs for the current CPU are forwarded to the new interface.

Because Linux does not use it, the SGI source information for the
forwarded SGIs is not preserved.  Neither is the source information
for the SGIs sent by the current CPU to other CPUs adjusted to match
the new CPU interface mapping.  The required registers are banked so
only the target CPU could do it.
Signed-off-by: Nicolas Pitre <nico@linaro.org>

Currently we hash the MPIDR of the CPU being suspended to determine which
entry in the sleep_save_sp array to use. In some situations, such as when
we want to resume on another physical CPU, the MPIDR of another CPU should
be used instead.

So let's use the value of cpu_logical_map(smp_processor_id()) in place
of the MPIDR in the suspend path.  This will result in the same index
being used as with the previous code unless the caller has modified
cpu_logical_map() beforehand with the MPIDR of the physical CPU the
suspending logical CPU will resume on.

Consequently, if doing a physical CPU migration, cpu_logical_map() must
be updated appropriately somewhere between cpu_pm_enter() and
cpu_suspend().

The register allocation in __cpu_suspend is reworked in order to better
accommodate the additional argument.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>

Merge tag 'pinctrl-for-v3.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control fixes from Linus Walleij:
 - Driver fixes for AM33xx, SIRF and PFC pin controllers
 - Fix a compile warning from the pinctrl single-register driver
 - Fix a little nasty memory leak

* tag 'pinctrl-for-v3.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: fix a memleak when freeing maps
  pinctrl: pinctrl-single: fix compile warning when no CONFIG_PM
  pinctrl: sh-pfc: fix SDHI0 VccQ regulator on sh73a0 with DT
  arm/dts: sirf: fix the pingroup name mismatch between drivers and dts
  pinctrl: sirf: add usp0_uart_nostreamctrl pin group for usp-uart without flowctrl
  pinctrl: sirf: fix the pin number and mux bit for usp0
  pinctrl: am33xx dt binding: correct include path

Merge tag 'trace-fixes-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Oleg is working on fixing a very tight race between opening a event
  file and deleting that event at the same time (both must be done as
  root).

  I also found a bug while testing Oleg's patches which has to do with a
  race with kprobes using the function tracer.

  There's also a deadlock fix that was introduced with the previous
  fixes"

* tag 'trace-fixes-3.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Remove locking trace_types_lock from tracing_reset_all_online_cpus()
  ftrace: Add check for NULL regs if ops has SAVE_REGS set
  tracing: Kill trace_cpu struct/members
  tracing: Change tracing_fops/snapshot_fops to rely on tracing_get_cpu()
  tracing: Change tracing_entries_fops to rely on tracing_get_cpu()
  tracing: Change tracing_stats_fops to rely on tracing_get_cpu()
  tracing: Change tracing_buffers_fops to rely on tracing_get_cpu()
  tracing: Change tracing_pipe_fops() to rely on tracing_get_cpu()
  tracing: Introduce trace_create_cpu_file() and tracing_get_cpu()

Pull SCSI fixes from James Bottomley:
 "This is five bug fixes, two of which fix long standing problems
  causing crashes (sd and mvsas).  The remaining three are hung (isci
  race) or lost (qla2xxx, isci) devices"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  [SCSI] isci: fix breakage caused by >16byte CDB patch
  [SCSI] mvsas: Fix kernel panic on tile due to unaligned data access
  [SCSI] sd: fix crash when UA received on DIF enabled device
  [SCSI] qla2xxx: Properly set the tagging for commands.
  [SCSI] isci: Fix a race condition in the SSP task management path

Pull drm fixes from Dave Airlie:
 "This is just a regular fixes pull apart from the qxl one, it has
  radeon and intel bits in it,

  The intel fixes are for a regression with the RC6 fix and a 3.10 hdmi
  regression, whereas radeon is more DPM fixes, a few lockup fixes and
  some rn50/r100 DAC fixes"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon/dpm: fix r600_enable_sclk_control()
  drm/radeon/dpm: implement force performance levels for rv6xx
  drm/radeon/dpm: fix displaygap programming on rv6xx
  drm/radeon/dpm: fix a typo in the rv6xx mclk setup
  drm/i915: initialize gt_lock early with other spin locks
  drm/i915: fix hdmi portclock limits
  drm/radeon: fix combios tables on older cards
  drm/radeon: improve dac adjust heuristics for legacy pdac
  drm/radeon: Another card with wrong primary dac adj
  drm/radeon: fix endian issues with DP handling (v3)
  drm/radeon/vm: only align the pt base to 32k
  drm/radeon: wait for 3D idle before using CP DMA

Pull qxl drm fixes from Dave Airlie:
 "Okay as I warned, the qxl driver was running a bit free and loose with
  its ttm object reservations and the new lockdep enabled reservation
  tracking shone a bright light into it, it also with the new
  reservations mutexes hits a possible deadlock during boot.

  The first patch is a real fix to render the console correctly as the
  driver used to just drop irq renderering as too hard, this also fixes
  a sleeping while atomic warning.

  The other two patches are the big ugly ones that redo how the driver
  allocates objects and reserves them and makes things all work
  properly, I've tested this in a VM, and compared to the current code
  which hits a lockdep warning and the sleep while atomic warning before
  failing.

  So sorry this is coming in late, I should have tested qxl before
  merging the mutex code, but I'd rather just fix qxl with this than
  revert the reservations code at this point"

* 'qxl-fixes' of git://people.freedesktop.org/~airlied/linux:
  qxl: convert qxl driver to proper use for reservations
  qxl: allow creation of pre-pinned objects and use for releases.
  drm/qxl: add delayed fb operations

Pull ACPI and power management fixes from Rafael Wysocki:
 "These are just two fixes, a revert of the would-be backlight fix that
  didn't work and an intel_pstate fix for two problems related to
  maximum P-state selection.

  Specifics:

   - Revert of the ACPI video commit that I hoped would help fix
     backlight problems related to Windows 8 compatibility on some
     systems.  Unfortunately, it turned out to cause problems to happen
     too.

   - Fix for two problems in intel_pstate, a possible failure to respond
     to a load change on a quiet system and a possible failure to select
     the highest available P-state on some systems.  From Dirk
     Brandewie"

* tag 'pm+acpi-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  Revert "ACPI / video / i915: No ACPI backlight if firmware expects Windows 8"
  cpufreq / intel_pstate: Change to scale off of max P-state

Pull arm64 fixes from Catalin Marinas:
 - Stack size increased to 16K (similar to other 64-bit architectures)
 - Additional cache flushing for secondary CPUs boot mode

* tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: Change kernel stack size to 16K
  arm64: Fix definition of arm_pm_restart to match the declaration
  arm64: virt: ensure visibility of __boot_cpu_mode

Pull ARM SoC fixes from Olof Johansson:
 "This is a largeish batch of fixes, mostly because I missed -rc2 due to
  travel/vacation.  So in number these are a bit more than ideal unless
  you amortize them over two -rcs.

  Quick breakdown:
   - Defconfig updates
     - Making multi_v7_defconfig useful on more hardware to encourage
       single-image usage
     - Davinci and nomadik updates due to new code merged this merge
       window
   - Fixes for UART on Samsung platforms, both PM and clock-related
   - A handful of warning fixes from defconfig builds, including for
     max8925 backlight and pxamci (both with appropriate acks)
   - Exynos5440 fixes for LPAE configuration, PM
   - ...plus a bunch of other smaller changes all over the place

  I expect to switch to regressions-or-severe-bugs-only fixes from here
  on out"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (37 commits)
  mfd: max8925: fix dt code for backlight
  ARM: omap5: Only select errata 798181 if SMP
  ARM: EXYNOS: Update CONFIG_ARCH_NR_GPIO for Exynos
  ARM: EXYNOS: Fix low level debug support
  ARM: SAMSUNG: Save/restore only selected uart's registers
  ARM: SAMSUNG: Add SAMSUNG_PM config option to select pm
  ARM: S3C24XX: Add missing clkdev entries for s3c2440 UART
  ARM: multi_v7_defconfig: Select USB chipidea driver
  ARM: pxa: propagate errors from regulator_enable() to pxamci
  ARM: zynq: fix compilation warning
  ARM: keystone: fix compilation warning
  ARM: highbank: Only touch common coherency control register fields
  ARM: footbridge: fix overlapping PCI mappings
  dmaengine: shdma: fix a build failure on platforms with no DMA support
  ARM: STi: Set correct ARM ERRATAs.
  ARM: dts: STi: Fix pinconf setup for STiH416 serial2
  ARM: nomadik: configure for NO_HZ and HRTIMERS
  ARM: nomadik: update defconfig base
  ARM: nomadik: Update MMC defconfigs
  ARM: davinci: defconfig: enable EDMA driver
  ...

Pull USB fixes from Greg KH:
 "Here are a number of USB fixes for 3.11-rc3.

  Lots of little things, nothing major.  A number of new device ids,
  build fixes for DMA, and a bunch of other minor things.  All of these
  have been in the linux-next tree"

* tag 'usb-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (40 commits)
  usb: Clear both buffers when clearing a control transfer TT buffer.
  usb/gadget: free opts struct on error recovery
  USB: mos7840: fix memory leak in open
  usb: serial: option.c: remove ONDA MT825UP product ID fromdriver
  usb: serial: option: add Olivetti Olicard 200
  usb: serial: option: blacklist ONDA MT689DC QMI interface
  xhci: fix null pointer dereference on ring_doorbell_for_active_rings
  usb: host: xhci: Enable XHCI_SPURIOUS_SUCCESS for all controllers with xhci 1.0
  usb: fix build warning in pci-quirks.h when CONFIG_PCI is not enabled
  usb: xhci: Mark two functions __maybe_unused
  xhci: Avoid NULL pointer deref when host dies.
  usb: serial: option: Add ONYX 3G device support
  USB: ti_usb_3410_5052: fix dynamic-id matching
  usb: option: add TP-LINK MA260
  USB: option: add D-Link DWM-152/C1 and DWM-156/C1
  USB: EHCI: Fix resume signalling on remote wakeup
  USB: cp210x: add MMB and PI ZigBee USB Device Support
  usb: cp210x support SEL C662 Vendor/Device
  USB: option: append Petatel NP10T device to GSM modems list
  USB: misc: Add Manhattan Hi-Speed USB DVI Converter to sisusbvga
  ...

Pull tty/serial fixes from Greg KH:
 "Here are 3 fixes for TTY and serial issues that have been reported.
  Nothing huge, but nice to get fixed"

* tag 'tty-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: tegra: correct help message in Kconfig from 'ttyHS' to 'ttyTHS'
  tty/8250_early: Don't truncate last character of options
  TTY: snyclinkmp: calculating wrong addresses

Pull staging fixes from Greg KH:
 "Here are some tiny drivers/staging/ fixes for 3.11-rc3

  A number of bugfixes, all pretty tiny, but resolve issues that have
  been reported (the kstrtos32 change fixes a data corruption problem
  that Dan found).  And a MAINTAINERS file update for the comedi
  drivers"

* tag 'staging-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  MAINTAINERS: Update the list of maintainers for staging/comedi driver.
  staging: tidspbridge: replace strict_strtol() with kstrtos32()
  staging: android: logger: Correct write offset reset on error
  staging: zram: protect zram_reset_device() call
  staging: gdm72xx: potential use after free in send_qos_list()
  staging: drm/imx: drop "select OF_VIDEOMODE"
  staging: frontier: use after free in disconnect()
  staging: comedi: fix a race between do_cmd_ioctl() and read/write
  staging: comedi: COMEDI_CANCEL ioctl should wake up read/write

Pull char/misc patches from Greg KH:
 "Here are some char/misc patches for 3.11-rc3.  It's pretty much just:
   - mei fixes
   - hyperv fixes
   - new ja_JP translation update
  all tiny stuff, but fixes for issues people have reported."

* tag 'char-misc-3.11-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  HOWTO ja_JP sync
  mei: me: fix waiting for hw ready
  mei: don't have to clean the state on power up
  mei: me: fix reset state machine
  mei: hbm: fix typo in error message
  Tools: hv: KVP: Fix a bug in IPV6 subnet enumeration
  Drivers: hv: balloon: Do not post pressure status if interrupted
  Drivers: hv: balloon: Fix a bug in the hot-add code
  Drivers: hv: vmbus: incorrect device name is printed when child device is unregistered

Pull sound fixes from Takashi Iwai:
 "Just a handful of regression and small fixes in ASoC, HD-audio and
  USB-audio drivers.

   - Sigmetal HD-audio codec regression fixes
   - A copule of XRUN indication fixes for usb-audio devices
   - ASoC: ep93xx build fix, sgtl5000 fix for probe order changes,
     max98088 register access fix, etc"

* tag 'sound-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hiface: return correct XRUN indication
  ASoC: tegra: correct playback_dma_data setup
  ASoC: core: double free in snd_soc_add_platform()
  ALSA: usb-audio: 6fire: return correct XRUN indication
  ASoC: ep93xx: fix build of ep93xx-ac97.c
  ALSA: hda - Remove NO_PRESENCE bit override for Dell 1420n Laptop
  ALSA: hda - Fix EAPD GPIO control for Sigmatel codecs
  ASoC: atmel-ssc: remove clk_disable_unprepare call from critical section
  ASoC: sgtl5000: defer the probe if clock is not found
  ASoC: max98088 - fix element type of the register cache.

Pull xfs fix from Ben Myers:
 "Fix for regression in commit cca9f93a ("xfs: don't do IO when
  creating an new inode"), recovery causing filesystem corruption after
  a crash"

* tag 'for-linus-v3.11-rc3' of git://oss.sgi.com/xfs/xfs:
  xfs: di_flushiter considered harmful

Pull nfsd fix from Bruce Fields:
 "One more nfsd bugfix for 3.11"

* 'for-3.11' of git://linux-nfs.org/~bfields/linux:
  nfsd: nfsd_open: when dentry_open returns an error do not propagate as struct file

Pull md fixes from Neil Brown:
 "Two more bugfixes for md in 3.11

  Both marked for -stable, both since 3.3.  I guess I should spend more
  time testing..."

* tag 'md/3.11-fixes' of git://neil.brown.name/md:
  md/raid5: fix interaction of 'replace' and 'recovery'.
  md/raid10: remove use-after-free bug.

Pull libata fixes from Tejun Heo:
 "Assorted libata updates.

  The most critical one is a fix for ahci oops during boot.  Also, a new
  smallish platform ahci driver is added and sata_inic162x is marked
  clearly as experimental (it whines during boot too) as data corruption
  seems rather common on the device and it's unlikely to get any love in
  the foreseeable future.  If the whining doesn't draw any attention, I
  think we'd probably be better of making the driver depend on BROKEN in
  a couple releases"

This is v2 of this pull request with fixed dependencies for ahci_imx.

* 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ahci_imx: depend on CONFIG_MFD_SYSCON
  ahci_imx: add ahci sata support on imx platforms
  ARM: imx6q: update the sata bits definitions of gpr13
  ahci: fix Null pointer dereference in achi_host_active()
  libata: make it clear that sata_inic162x is experimental
  libata: replace strict_strtol() with kstrtol()
  ata: Fix DVD not dectected at some platform with Wellsburg PCH

We attempted to address a regression introduced by commit a57f7f91
(ACPICA: Add Windows8/Server2012 string for _OSI method.) after which
ACPI video backlight support doesn't work on a number of systems,
because the relevant AML methods in the ACPI tables in their BIOSes
become useless after the BIOS has been told that the OS is compatible
with Windows 8.  That problem is tracked by the bug entry at:

https://bugzilla.kernel.org/show_bug.cgi?id=51231

Commit 8c5bd7ad (ACPI / video / i915: No ACPI backlight if firmware
expects Windows 8) introduced for this purpose essentially prevented
the ACPI backlight support from being used if the BIOS had been told
that the OS was compatible with Windows 8 and the i915 driver was
loaded, in which case the backlight would always be handled by i915.
Unfortunately, however, that turned out to cause problems with
backlight to appear on multiple systems with symptoms indicating that
i915 was unable to control the backlight on those systems as
expected.

For this reason, revert commit 8c5bd7ad, but leave the function
acpi_video_backlight_quirks() introduced by it, because another
commit on top of it uses that function.

References: https://lkml.org/lkml/2013/7/21/119
References: https://lkml.org/lkml/2013/7/22/261
References: https://lkml.org/lkml/2013/7/23/429
References: https://lkml.org/lkml/2013/7/23/459
References: https://lkml.org/lkml/2013/7/23/81
References: https://lkml.org/lkml/2013/7/24/27Reported-and-tested-by: James Hogan <james@albanarts.com>
Reported-and-tested-by: Kamal Mostafa <kamal@canonical.com>
Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Reported-and-tested-by: Steven Newbury <steve@snewbury.org.uk>
Reported-by: Martin Steigerwald <Martin@lichtvoll.de>
Reported-by: Kalle Valo <kvalo@adurom.com>
Tested-by: Joerg Platte <jplatte@naasa.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ahci_imx makes use of regmap but the dependency wasn't specified in
Kconfig leading build failures if CONFIG_AHCI_IMX is enabled but
CONFIG_MFD_SYSCON is not.  Add the Kconfig dependency.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>

Commit a8227415 "tracing: Protect ftrace_trace_arrays list in trace_events.c"
added taking the trace_types_lock mutex in trace_events.c as there were
several locations that needed it for protection. Unfortunately, it also
encapsulated a call to tracing_reset_all_online_cpus() which also takes
the trace_types_lock, causing a deadlock.

This happens when a module has tracepoints and has been traced. When the
module is removed, the trace events module notifier will grab the
trace_types_lock, do a bunch of clean ups, and also clears the buffer
by calling tracing_reset_all_online_cpus. This doesn't happen often
which explains why it wasn't caught right away.

Commit a8227415 was marked for stable, which means this must be
sent to stable too.

Link: http://lkml.kernel.org/r/51EEC646.7070306@broadcom.comReported-by: Arend van Spril <arend@broadcom.com>
Tested-by: Arend van Spriel <arend@broadcom.com>
Cc: Alexander Z Lam <azl@google.com>
Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Cc: David Sharp <dhsharp@google.com>
Cc: stable@vger.kernel.org # 3.10
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Written by Catalin Marinas, tested by APM on storm platform. This is needed
because of the failures encountered when running SpecWeb benchmark test.
Signed-off-by: Feng Kan <fkan@apm.com>
Acked-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Merge tag 'drm-intel-fixes-2013-07-25' of git://people.freedesktop.org/~danvet/drm-intel into drm-fixes

Brown-paper-bag pull request here. The snb rc6 fix from the last pull
broke forcewake BIOS dirt cleanup, which with fixed. But that fix broke
the spinlock init sequence, which results in an ugly BUG when spinlock
debugging is enabled :( So I get to throw another patch at cc: stable to
fix up the mess ...

* tag 'drm-intel-fixes-2013-07-25' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: initialize gt_lock early with other spin locks
  drm/i915: fix hdmi portclock limits

r600 dpm fixes, old school card dac fixes, lockup fixes
endian fixes
* 'drm-fixes-3.11' of git://people.freedesktop.org/~agd5f/linux:
  drm/radeon/dpm: fix r600_enable_sclk_control()
  drm/radeon/dpm: implement force performance levels for rv6xx
  drm/radeon/dpm: fix displaygap programming on rv6xx
  drm/radeon/dpm: fix a typo in the rv6xx mclk setup
  drm/radeon: fix combios tables on older cards
  drm/radeon: improve dac adjust heuristics for legacy pdac
  drm/radeon: Another card with wrong primary dac adj
  drm/radeon: fix endian issues with DP handling (v3)
  drm/radeon/vm: only align the pt base to 32k
  drm/radeon: wait for 3D idle before using CP DMA

Actually program the correct register to enable
engine clock scaling control.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Allows you to limit the selected power levels via sysfs.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

The device-tree enablement for max8925 has several problems, but besides
the bindings being wrong (and not having seen review) there's also some
bad coding practices on how to fill in the platform_data from device tree.

I came across this since it causes a warning when compiling
mmp2_defconfig, and instead of doing the minimal fix to silence the
warning, I restructured the code a bit.

This silences the warning:
drivers/video/backlight/max8925_bl.c: In function 'max8925_backlight_probe':
drivers/video/backlight/max8925_bl.c:177:3: warning: statement with no effect [-Wunused-value]

Note that the bindings themselves need to be revisited too, but that will
affect more than just the backlight driver and is best done separately;
this just fixes the bad code for the backlight driver.
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Olof Johansson <olof@lixom.net>

Need to use the driver state rather than the register
state since the displays may not be enabled when the
power state is programmed.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>