cpufreq: cpufreq-dt: disable unsupported OPPs

If the regulator connected to the CPU voltage plane doesn't
support an OPP specified voltage with the acceptable tolerance
it's better to just disable the OPP instead of constantly
failing the voltage scaling later on.

Includes a fix to move initialization of opp_freq outside
the loop to avoid an endless loop from Geert Uytterhoeven.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI: Use ACPI companion to match only the first physical device

Commit 6ab3430129e2 ("mfd: Add ACPI support") made the MFD subdevices
share the parent MFD ACPI companion if no _HID/_CID is specified for
the subdevice in mfd_cell description. However, since all the subdevices
share the ACPI companion, the match and modalias generation logic started
to use the ACPI companion as well resulting this:

  # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias
  acpi:INT33D1:PNP0C50:

instead of the expected one

  # cat /sys/bus/platform/devices/HID-SENSOR-200041.6.auto/modalias
  platform:HID-SENSOR-200041

In other words the subdevice modalias is overwritten by the one taken from
ACPI companion. This causes udev not to load the driver anymore.

It is useful to be able to share the ACPI companion so that MFD subdevices
(and possibly other devices as well) can access the ACPI resources even if
they do not have ACPI representation in the namespace themselves.

An example where this is used is Minnowboard LPC driver that creates GPIO
as a subdevice among other things. Without the ACPI companion gpiolib is
not able to lookup the corresponding GPIO controller from ACPI GpioIo
resource.

To fix this, restrict the match and modalias logic to be limited to the
first (primary) physical device associated with the given ACPI comapnion.
The secondary devices will still be able to access the ACPI companion,
but they will be matched in a different way.

Fixes: 6ab3430129e2 (mfd: Add ACPI support)
Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / Sleep: fix async suspend_late/freeze_late error handling

If an asynchronous suspend_late or freeze_late callback fails
during the SUSPEND, FREEZE or QUIESCE phases, we don't propagate the
corresponding error correctly, in effect ignoring the error and
continuing the suspend-to-ram/hibernation. During suspend-to-ram this
could leave some devices without a valid saved context, leading to a
failure to reinitialize them during resume. During hibernation this
could leave some devices active interfeering with the creation /
restoration of the hibernation image. Also this could leave the
corresponding devices without a valid saved context and failure to
reinitialize them during resume.

Fixes: de377b397272 (PM / sleep: Asynchronous threads for suspend_late)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Cc: 3.15+ <stable@vger.kernel.org> # 3.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PM / Sleep: fix recovery during resuming from hibernation

If a device's dev_pm_ops::freeze callback fails during the QUIESCE
phase, we don't rollback things correctly calling the thaw and complete
callbacks. This could leave some devices in a suspended state in case of
an error during resuming from hibernation.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert duplicate "PCI: pciehp: Prevent NULL dereference during probe"

This reverts bceee4a97eb5 ("PCI: pciehp: Prevent NULL dereference during
probe") because it was accidentally applied twice:

  62e4492c3063 ("PCI: Prevent NULL dereference during pciehp probe")
  bceee4a97eb5 ("PCI: pciehp: Prevent NULL dereference during probe")

Revert the latter to dispose of the duplicated code block.

[bhelgaas: tidy changelog, drop stable tag]
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Andreas Noever <andreas.noever@gmail.com>
cpufreq: cpufreq-dt: Restore default cpumask_setall(policy->cpus)

Commit 34e5a5273d6aa0ee ("cpufreq: cpufreq-dt: extend with
platform_data") changed cpufreq_init() to only call
cpumask_setall(policy->cpus) if the platform data indicates that all
CPUs share the same clock. Before, cpufreq_generic_init() did this
unconditionally.

This causes a crash on r8a7791/koelsch when resuming from s2ram:

    Enabling non-boot CPUs ...
    CPU1: Booted secondary processor
    Unable to handle kernel NULL pointer dereference at virtual address 0000003c
    pgd = ee71f980
    [0000003c] *pgd=6eeb6003, *pmd=6e0e9003, *pte=00000000
    Internal error: Oops: a07 [#1] SMP ARM
    Modules linked in:
    CPU: 0 PID: 1397 Comm: s2ram Tainted: G        W      3.18.0-rc2-koelsch-00762-g7eed2a4e61d2d978 #581
    task: ee6b76c0 ti: ee7f0000 task.ti: ee7f0000
    PC is at __cpufreq_add_dev.isra.24+0x24c/0x77c
    LR is at __cpufreq_add_dev.isra.24+0x244/0x77c
    pc : [<c029e084>]    lr : [<c029e07c>]    psr: 60000153
    sp : ee7f1d48  ip : ee7f1d48  fp : ee7f1d84
    r10: c04e8448  r9 : 00000000  r8 : 00000001
    r7 : c054a8c4  r6 : 00000001  r5 : 00000001  r4 : 00000000
    r3 : 00000000  r2 : 00000000  r1 : 20000153  r0 : c054a950
    Flags: nZCv  IRQs on  FIQs off  Mode SVC_32  ISA ARM  Segment user
    Control: 30c5307d  Table: 6e71f980  DAC: fffffffd
    Process s2ram (pid: 1397, stack limit = 0xee7f0240)

    ...

    Backtrace:
    [<c029de38>] (__cpufreq_add_dev.isra.24) from [<c029e620>] (cpufreq_cpu_callback+0x6c/0x74)
     r10:eec75240 r9:c04e8448 r8:c04ef3a0 r7:00000001 r6:00000012 r5:00000000
     r4:00000012
    [<c029e5b4>] (cpufreq_cpu_callback) from [<c003f20c>] (notifier_call_chain+0x48/0x70)
     r4:ffffffdd r3:c029e5b4
    [<c003f1c4>] (notifier_call_chain) from [<c003f2cc>] (__raw_notifier_call_chain+0x1c/0x24)
     r8:00000001 r7:00000010 r6:00000000 r5:00000000 r4:00000012 r3:ffffffff
    [<c003f2b0>] (__raw_notifier_call_chain) from [<c0026a00>] (__cpu_notify+0x34/0x50)
    [<c00269cc>] (__cpu_notify) from [<c0026a34>] (cpu_notify+0x18/0x1c)
     r4:00000001
    [<c0026a1c>] (cpu_notify) from [<c0026c44>] (_cpu_up+0x108/0x144)
    [<c0026b3c>] (_cpu_up) from [<c0381c68>] (enable_nonboot_cpus+0x68/0xb8)
     r10:00000000 r9:c04e8ee6 r8:00000000 r7:00000003 r6:c04e8528 r5:c0506248
     r4:00000001
    [<c0381c00>] (enable_nonboot_cpus) from [<c0059038>] (suspend_devices_and_enter+0x29c/0x3e8)
     r6:c0506e70 r5:00000000 r4:00000000 r3:60000153

Restore the old default of calling cpumask_setall(policy->cpus) if no
platform data is available to fix this.

Fixes: 34e5a5273d6aa0ee (cpufreq: cpufreq-dt: extend with platform_data)
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert "ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC"

It is reported that the following commit breaks Samsung hardware:
 Commit: 558e4736f2e1b0e6323adf7a5e4df77ed6cfc1a4.
 Subject: ACPI / EC: Add support to disallow QR_EC to be issued before
          completing previous QR_EC

Which means the Samsung behavior conflicts with the Acer behavior.

1. Samsung may behave like:
   [ +event 1 ] SCI_EVT set
   [ +event 2 ] SCI_EVT set
                              write QR_EC
                              read event
   [ -event 1 ] SCI_EVT clear
   Without the above commit, Samsung can work:
   [ +event 1 ] SCI_EVT set
   [ +event 2 ] SCI_EVT set
                              write QR_EC
                              CAN prepare next QR_EC as SCI_EVT=1
                              read event
   [ -event 1 ] SCI_EVT clear
                              write QR_EC
                              read event
   [ -event 2 ] SCI_EVT clear
   With the above commit, Samsung cannot work:
   [ +event 1 ] SCI_EVT set
   [ +event 2 ] SCI_EVT set
                              write QR_EC
                              read event
   [ -event 1 ] SCI_EVT clear
                              CANNOT prepare next QR_EC as SCI_EVT=0
2. Acer may behave like:
   [ +event 1 ] SCI_EVT set
   [ +event 2 ]
                              write QR_EC
                              read event
   [ -event 1 ] SCI_EVT clear
   [ +event 2 ] SCI_EVT set
   Without the above commit, Acer cannot work when there is only 1 event:
   [ +event 1 ] SCI_EVT set
                              write QR_EC
                              can prepared next QR_EC as SCI_EVT=1
                              read event
   [ -event 1 ] SCI_EVT clear
                              CANNOT write QR_EC as SCI_EVT=0
   With the above commit, Acer can work:
   [ +event 1 ] SCI_EVT set
   [ +event 2 ]
                              write QR_EC
                              read event
   [ -event 1 ] SCI_EVT set
                              can prepare next QR_EC because SCI_EVT=0
                              CAN write QR_EC as SCI_EVT=1

Since Acer can also work with only the following commit applied:
 Commit: 3afcf2ece453e1a8c2c6de19cdf06da3772a1b08
 Subject: ACPI / EC: Add support to disallow QR_EC to be issued when
          SCI_EVT isn't set
commit 558e4736f2e1b0e6323adf7a5e4df77ed6cfc1a4 can be reverted.

Fixes: 558e4736f2e1 (ACPI / EC: Add support to disallow QR_EC to be issued ...)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=44161
Reported-and-tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: 3.17+ <stable@vger.kernel.org> # 3.17+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / EC: Fix regression due to conflicting firmware behavior between Samsung and Acer.

It is reported that Samsung laptops that need to poll events are broken by
the following commit:
 Commit 3afcf2ece453e1a8c2c6de19cdf06da3772a1b08
 Subject: ACPI / EC: Add support to disallow QR_EC to be issued when SCI_EVT isn't set

The behaviors of the 2 vendor firmwares are conflict:
 1. Acer: OSPM shouldn't issue QR_EC unless SCI_EVT is set, firmware
         automatically sets SCI_EVT as long as there is event queued up.
 2. Samsung: OSPM should issue QR_EC whatever SCI_EVT is set, firmware
            returns 0 when there is no event queued up.

This patch is a quick fix to distinguish the behaviors to make Acer
behavior only effective for Acer EC firmware so that the breakages on
Samsung EC firmware can be avoided.

Fixes: 3afcf2ece453 (ACPI / EC: Add support to disallow QR_EC to be issued ...)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=44161
Reported-and-tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: 3.17+ <stable@vger.kernel.org> # 3.17+
[ rjw : Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PCI: imx6: Wait for clocks to stabilize after ref_en

For boards without a reset GPIO we skip the delay between enabling the
pcie_ref_clk and touching the RC registers for configuration.  This hangs
the system if there isn't a proper delay to ensure the clocks are settled
in the DW PCIe core.

Also iMX6Q always needs an additional 10us delay to make sure the reset is
propagated through the core, as we don't have an explicitly controlled
reset input on this SoC.

This fixes a problem with 3fce0e882f61 ("PCI: imx6: Delay enabling
reference clock for SS until it stabilizes"): the kernel doesn't boot on
systems that don't pass the PCI GPIO reset in the DTB.  This regression
affects mx6 nitrogen boards.

[bhelgaas: add regression info in changelog]
Fixes: 3fce0e882f61 ("PCI: imx6: Delay enabling reference clock for SS until it stabilizes")
Reported-by: Fabio Estevam <fabio.estevam@freescale.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Richard Zhu <richard.zhu@freescale.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Lucas Stach <l.stach@pengutronix.de>
PCI: Rename sysfs 'enabled' file back to 'enable'

Back in commit 5136b2da770d ("PCI: convert bus code to use dev_groups"),
I misstyped the 'enable' sysfs filename as 'enabled', which broke the
userspace API.  This patch fixes that issue by renaming the file back.

Fixes: 5136b2da770d ("PCI: convert bus code to use dev_groups")
Reported-by: Jeff Epler <jepler@unpythonic.net>
Tested-by: Jeff Epler <jepler@unpythonic.net>	# on v3.14-rt
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# 3.13
Merge branches 'acpi-scan' and 'acpi-ec'

* acpi-scan:
  ACPI: Use ACPI companion to match only the first physical device

* acpi-ec:
  ACPI / EC: Fix regression due to conflicting firmware behavior between Samsung and Acer.
  Revert "ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC"
Merge branches 'pm-cpufreq' and 'pm-sleep'

* pm-cpufreq:
  cpufreq: cpufreq-dt: Restore default cpumask_setall(policy->cpus)
  cpufreq: cpufreq-dt: disable unsupported OPPs

* pm-sleep:
  PM / Sleep: fix recovery during resuming from hibernation
  PM / Sleep: fix async suspend_late/freeze_late error handling
x86_64, entry: Fix out of bounds read on sysenter

Rusty noticed a Really Bad Bug (tm) in my NT fix.  The entry code
reads out of bounds, causing the NT fix to be unreliable.  But, and
this is much, much worse, if your stack is somehow just below the
top of the direct map (or a hole), you read out of bounds and crash.

Excerpt from the crash:

[    1.129513] RSP: 0018:ffff88001da4bf88  EFLAGS: 00010296

  2b:*    f7 84 24 90 00 00 00     testl  $0x4000,0x90(%rsp)

That read is deterministically above the top of the stack.  I
thought I even single-stepped through this code when I wrote it to
check the offset, but I clearly screwed it up.

Fixes: 8c7aa698baca ("x86_64, entry: Filter RFLAGS.NT on entry from userspace")
Reported-by: Rusty Russell <rusty@ozlabs.org>
Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag 'pci-v3.18-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:
 "These changes, intended for v3.18, fix:

  Sysfs
    - Fix "enable" filename change (Greg Kroah-Hartman)

      An unintentional sysfs filename change in commit 5136b2da770d
      ("PCI: convert bus code to use dev_groups"), which appeared in
      v3.13, changed "enable" to "enabled", and this changes it back.

      Old users of "enable" are currently broken and will be helped by
      this change.  Anything that started to use "enabled" after v3.13
      will be broken by this change.  If necessary, we can add a symlink
      to make both work, but this patch doesn't do that.

  PCI device hotplug
    - Revert duplicate merge (Kamal Mostafa)

      A mistaken duplicate merge that added a check twice.  Nothing's
      broken; this just removes the unnecessary code.

  Freescale i.MX6
    - Wait for clocks to stabilize after ref_en (Richard Zhu)

      An i.MX6 clock problem that prevents mx6 nitrogen boards from booting"

* tag 'pci-v3.18-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: Rename sysfs 'enabled' file back to 'enable'
  PCI: imx6: Wait for clocks to stabilize after ref_en
  Revert duplicate "PCI: pciehp: Prevent NULL dereference during probe"
Merge tag 'pm+acpi-3.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:
 "These are fixes received after my previous pull request plus one that
  has been in the works for quite a while, but its previous version
  caused problems to happen, so it's been deferred till now.

  Fixed are two recent regressions (MFD enumeration and cpufreq-dt),
  ACPI EC regression introduced in 3.17, system suspend error code path
  regression introduced in 3.15, an older bug related to recovery from
  failing resume from hibernation and a cpufreq-dt driver issue related
  to operation performance points.

  Specifics:

   - Fix a crash on r8a7791/koelsch during resume from system suspend
     caused by a recent cpufreq-dt commit (Geert Uytterhoeven).

   - Fix an MFD enumeration problem introduced by a recent commit adding
     ACPI support to the MFD subsystem that exposed a weakness in the
     ACPI core causing ACPI enumeration to be applied to all devices
     associated with one ACPI companion object, although it should be
     used for one of them only (Mika Westerberg).

   - Fix an ACPI EC regression introduced during the 3.17 cycle causing
     some Samsung laptops to misbehave as a result of a workaround
     targeted at some Acer machines.  That includes a revert of a commit
     that went too far and a quirk for the Acer machines in question.
     From Lv Zheng.

   - Fix a regression in the system suspend error code path introduced
     during the 3.15 cycle that causes it to fail to take errors from
     asychronous execution of "late" suspend callbacks into account
     (Imre Deak).

   - Fix a long-standing bug in the hibernation resume error code path
     that fails to roll back everything correcty on "freeze" callback
     errors and leaves some devices in a "suspended" state causing more
     breakage to happen subsequently (Imre Deak).

   - Make the cpufreq-dt driver disable operation performance points
     that are not supported by the VR connected to the CPU voltage plane
     with acceptable tolerance instead of constantly failing voltage
     scaling later on (Lucas Stach)"

* tag 'pm+acpi-3.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / EC: Fix regression due to conflicting firmware behavior between Samsung and Acer.
  Revert "ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC"
  cpufreq: cpufreq-dt: Restore default cpumask_setall(policy->cpus)
  PM / Sleep: fix recovery during resuming from hibernation
  PM / Sleep: fix async suspend_late/freeze_late error handling
  ACPI: Use ACPI companion to match only the first physical device
  cpufreq: cpufreq-dt: disable unsupported OPPs