Commit Graph

116 Commits

Author SHA1 Message Date
Victor Ding c254bcd723 rtc: cmos: zero-init wkalrm when reading from CMOS
cmos_read_alarm() may leave certain fields of a struct rtc_wkalrm
untouched; therefore, these fields contain garbage if not properly
initialized, leading to inconsistent values when converting into
time64_t. This patch to zero initialize the struct before calling
cmos_read_alarm().

Note that this patch is not intended to produce a correct time64_t, it
is only to produce a consistent value. In the case of suspend/resume, a
correct time64_t is not necessary; a consistent value is sufficient to
correctly perform an equality test for t_current_expires and
t_saved_expires. Logic to deduce a correct time64_t is expensive and
hence should be avoided.

Signed-off-by: Victor Ding <victording@google.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200814191654.v2.1.Iaf7638a2f2a87ff68d85fcb8dec615e41340c97f@changeid
2020-08-21 00:10:33 +02:00
Linus Torvalds bdabb68931 RTC for 5.7
Subsystem:
  - The rtc_time_to_tm and rtc_tm_to_time wrappers have finally been removed and
    only the 64bit version remain.
  - hctosys now works with drivers compiled as modules
 
 New driver:
  - MediaTek MT2712 SoC based RTC
 
 Drivers:
  - set range for 88pm860x, au1xxx, cpcap, da9052, davinci, ds1305, ds1374,
    mcp5121, pl030, pl031, pm8xxx, puv3, sa1100, sirfsoc, starfire, sun6i
  - ds1307: DS1388 oscillator failure detection and watchdog support
  - jz4740: JZ4760 support
  - pcf85063: clock out pin support
  - sun6i: external 32k oscillator is now optional, the range is now handled by
    the core, providing a solution for 2034.
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Merge tag 'rtc-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "More cleanup this cycle, with the final goal of removing the
  rtc_time_to_tm and rtc_tm_to_time wrappers. All the drivers that have
  been modified for this now are ready for the end of times (whether it
  happens in 2033, 2038, 2106, 2127 or even 4052). There is also a
  single new driver and the usual fixes and features.

  Summary:

  Subsystem:

   - The rtc_time_to_tm and rtc_tm_to_time wrappers have finally been
     removed and only the 64bit version remain.

   - hctosys now works with drivers compiled as modules

  New driver:

   - MediaTek MT2712 SoC based RTC

  Drivers:

   - set range for 88pm860x, au1xxx, cpcap, da9052, davinci, ds1305,
     ds1374, mcp5121, pl030, pl031, pm8xxx, puv3, sa1100, sirfsoc,
     starfire, sun6i

   - ds1307: DS1388 oscillator failure detection and watchdog support

   - jz4740: JZ4760 support

   - pcf85063: clock out pin support

   - sun6i: external 32k oscillator is now optional, the range is now
     handled by the core, providing a solution for 2034"

* tag 'rtc-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (87 commits)
  rtc: ds1307: check for failed memory allocation on wdt
  rtc: class: remove redundant assignment to variable err
  rtc: remove rtc_time_to_tm and rtc_tm_to_time
  rtc: sun6i: let the core handle rtc range
  rtc: sun6i: switch to rtc_time64_to_tm/rtc_tm_to_time64
  rtc: ds1307: add support for watchdog timer on ds1388
  rtc: da9052: switch to rtc_time64_to_tm/rtc_tm_to_time64
  rtc: da9052: set range
  rtc: da9052: convert to devm_rtc_allocate_device
  rtc: imx-sc: Align imx sc msg structs to 4
  rtc: fsl-ftm-alarm: report alarm to core
  rtc: pcf85063: Add pcf85063 clkout control to common clock framework
  rtc: make definitions in include/uapi/linux/rtc.h actually useful for user space
  rtc: class: avoid unnecessary lookup in hctosys
  dt-bindings: rtc: Convert and update jz4740-rtc doc to YAML
  rtc: jz4740: Rename vendor-specific DT properties
  rtc: jz4740: Add support for JZ4760 SoC
  rtc: class: support hctosys from modular RTC drivers
  rtc: pm8xxx: clear alarm register when alarm is not enabled
  rtc: omap: drop unused dt-bindings header
  ...
2020-04-04 10:38:01 -07:00
Corentin Labbe 8d4e59ec94 rtc: cmos: remove useless cast for driver_name
Now the pnp_driver name is "const char *", there are no need to cast
driver_name.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-17 18:32:07 +01:00
Ville Syrjälä 66e4f4a9cc rtc: cmos: Use spin_lock_irqsave() in cmos_interrupt()
cmos_interrupt() isn't always called from hardirq context, so
we must use spin_lock_irqsave() & co.

================================
WARNING: inconsistent lock state
5.6.0-rc2-CI-CI_DRM_7981+ #1 Tainted: G     U
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
rtcwake/4315 [HC0[0]:SC0[0]:HE1:SE1] takes:
ffffffff82635198 (rtc_lock){?...}, at: cmos_interrupt+0x18/0x100
{IN-HARDIRQ-W} state was registered at:
  lock_acquire+0xa7/0x1c0
  _raw_spin_lock+0x2a/0x40
  cmos_interrupt+0x18/0x100
  rtc_handler+0x75/0xc0
  acpi_ev_fixed_event_detect+0xf9/0x132
  acpi_ev_sci_xrupt_handler+0xb/0x28
  acpi_irq+0x13/0x30
  __handle_irq_event_percpu+0x41/0x2c0
  handle_irq_event_percpu+0x2b/0x70
  handle_irq_event+0x2f/0x50
  handle_fasteoi_irq+0x8e/0x150
  do_IRQ+0x7e/0x160
  ret_from_intr+0x0/0x35
  mwait_idle+0x7e/0x200
  do_idle+0x1bb/0x260
  cpu_startup_entry+0x14/0x20
  start_secondary+0x15f/0x1b0
  secondary_startup_64+0xa4/0xb0
irq event stamp: 42003
hardirqs last  enabled at (42003): [<ffffffff81a36567>] _raw_spin_unlock_irqrestore+0x47/0x60
hardirqs last disabled at (42002): [<ffffffff81a362ed>] _raw_spin_lock_irqsave+0xd/0x50
softirqs last  enabled at (41848): [<ffffffff81e00385>] __do_softirq+0x385/0x47f
softirqs last disabled at (41841): [<ffffffff810bab3a>] irq_exit+0xba/0xc0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(rtc_lock);
  <Interrupt>
    lock(rtc_lock);

 *** DEADLOCK ***

6 locks held by rtcwake/4315:
 #0: ffff888175dc9408 (sb_writers#5){.+.+}, at: vfs_write+0x1a4/0x1d0
 #1: ffff88817406ca80 (&of->mutex){+.+.}, at: kernfs_fop_write+0xdd/0x1b0
 #2: ffff888179be85e0 (kn->count#236){.+.+}, at: kernfs_fop_write+0xe6/0x1b0
 #3: ffffffff82641e00 (system_transition_mutex){+.+.}, at: pm_suspend+0xb3/0x3b0
 #4: ffffffff826b3ee0 (acpi_scan_lock){+.+.}, at: acpi_suspend_begin+0x47/0x80
 #5: ffff888178fc3960 (&dev->mutex){....}, at: device_resume+0x92/0x1c0

stack backtrace:
CPU: 3 PID: 4315 Comm: rtcwake Tainted: G     U            5.6.0-rc2-CI-CI_DRM_7981+ #1
Hardware name: Google Soraka/Soraka, BIOS MrChromebox-4.10 08/25/2019
Call Trace:
 dump_stack+0x71/0x9b
 mark_lock+0x49a/0x500
 ? print_shortest_lock_dependencies+0x200/0x200
 __lock_acquire+0x6d4/0x15d0
 ? __lock_acquire+0x460/0x15d0
 lock_acquire+0xa7/0x1c0
 ? cmos_interrupt+0x18/0x100
 _raw_spin_lock+0x2a/0x40
 ? cmos_interrupt+0x18/0x100
 cmos_interrupt+0x18/0x100
 cmos_resume+0x1fd/0x290
 ? __acpi_pm_set_device_wakeup+0x24/0x100
 pnp_bus_resume+0x5e/0x90
 ? pnp_bus_suspend+0x10/0x10
 dpm_run_callback+0x64/0x280
 device_resume+0xd4/0x1c0
 ? dpm_watchdog_set+0x60/0x60
 dpm_resume+0x106/0x410
 ? dpm_resume_early+0x38c/0x3e0
 dpm_resume_end+0x8/0x10
 suspend_devices_and_enter+0x16f/0xbe0
 ? rcu_read_lock_sched_held+0x4d/0x80
 pm_suspend+0x344/0x3b0
 state_store+0x78/0xe0
 kernfs_fop_write+0x112/0x1b0
 vfs_write+0xb9/0x1d0
 ksys_write+0x9f/0xe0
 do_syscall_64+0x4f/0x220
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7ff934307154
Code: 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 8d 05 b1 07 2e 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 41 54 55 49 89 d4 53 48 89 f5
RSP: 002b:00007ffe2647c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007ff934307154
RDX: 0000000000000004 RSI: 000055de3ec4e5a0 RDI: 000000000000000a
RBP: 000055de3ec4e5a0 R08: 000055de3ec4c5e0 R09: 00007ff9349f3740
R10: 000055de3ec4a010 R11: 0000000000000246 R12: 000055de3ec4c500
R13: 0000000000000004 R14: 00007ff9345df2a0 R15: 00007ff9345de760

Fixes: c6d3a278cc ("rtc: cmos: acknowledge ACPI driven wake alarms upon resume")
Fixes: 311ee9c151 ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://lore.kernel.org/r/20200221144739.11746-1-ville.syrjala@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-03-03 11:56:42 +01:00
Andy Shevchenko 604c521259 rtc: cmos: Refactor code by using the new dmi_get_bios_year() helper
Refactor code by using the new dmi_get_bios_year() helper instead of
open coding its functionality. This also makes logic slightly clearer.

No changes intended.

Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200123131437.28157-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-01-25 21:55:14 +01:00
Andy Shevchenko 5848ad2f1b rtc: cmos: Use predefined value for RTC IRQ on legacy x86
When legacy devices are present on x86 machine, the RTC IRQ has
a dedicated pre-defined value. Use it instead of hard coded number.

Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200123131437.28157-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-01-25 21:55:12 +01:00
Andy Shevchenko b6da197a2e rtc: cmos: Stop using shared IRQ
As reported by Guilherme G. Piccoli:

---8<---8<---8<---

The rtc-cmos interrupt setting was changed in the commit 079062b28f
("rtc: cmos: prevent kernel warning on IRQ flags mismatch") in order
to allow shared interrupts; according to that commit's description,
some machine got kernel warnings due to the interrupt line being shared
between rtc-cmos and other hardware, and rtc-cmos didn't allow IRQ sharing
that time.

After the aforementioned commit though it was observed a huge increase
in lost HPET interrupts in some systems, observed through the following
kernel message:

[...] hpet1: lost 35 rtc interrupts

After investigation, it was narrowed down to the shared interrupts
usage when having the kernel option "irqpoll" enabled. In this case,
all IRQ handlers are called for non-timer interrupts, if such handlers
are setup in shared IRQ lines. The rtc-cmos IRQ handler could be set to
hpet_rtc_interrupt(), which will produce the kernel "lost interrupts"
message after doing work - lots of readl/writel to HPET registers, which
are known to be slow.

Although "irqpoll" is not a default kernel option, it's used in some contexts,
one being the kdump kernel (which is an already "impaired" kernel usually
running with 1 CPU available), so the performance burden could be considerable.
Also, the same issue would happen (in a shorter extent though) when using
"irqfixup" kernel option.

In a quick experiment, a virtual machine with uptime of 2 minutes produced
>300 calls to hpet_rtc_interrupt() when "irqpoll" was set, whereas without
sharing interrupts this number reduced to 1 interrupt. Machines with more
hardware than a VM should generate even more unnecessary HPET interrupts
in this scenario.

---8<---8<---8<---

After looking into the rtc-cmos driver history and DSDT table from
the Microsoft Surface 3, we may notice that Hans de Goede submitted
a correct fix (see dependency below). Thus, we simply revert
the culprit commit.

Fixes: 079062b28f ("rtc: cmos: prevent kernel warning on IRQ flags mismatch")
Depends-on: a1e23a42f1 ("rtc: cmos: Do not assume irq 8 for rtc when there are no legacy irqs")
Reported-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200123131437.28157-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2020-01-25 21:54:57 +01:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Hans de Goede fbb974ba69 rtc: cmos: Do not export alarm rtc_ops when we do not support alarms
When there is no IRQ configured for the RTC, the rtc-cmos code does not
support alarms, all alarm rtc_ops fail with -EIO / -EINVAL.

The rtc-core expects a rtc driver which does not support rtc alarms to
not have alarm ops at all. Otherwise the wakealarm sysfs attr will read
as empty rather then returning an error, making it impossible for
userspace to find out beforehand if alarms are supported.

A system without an IRQ for the RTC before this patch:
[root@localhost ~]# cat /sys/class/rtc/rtc0/wakealarm
[root@localhost ~]#

After this patch:
[root@localhost ~]# cat /sys/class/rtc/rtc0/wakealarm
cat: /sys/class/rtc/rtc0/wakealarm: No such file or directory
[root@localhost ~]#

This fixes gnome-session + systemd trying to use suspend-then-hibernate,
which causes systemd to abort the suspend when writing the RTC alarm fails.

BugLink: https://github.com/systemd/systemd/issues/9988
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-11-07 17:13:55 +01:00
Maciej W. Rozycki bc51098cdd rtc: cmos: Remove the `use_acpi_alarm' module parameter for !ACPI
Fix a problem with commit 311ee9c151 ("rtc: cmos: allow using ACPI for
RTC alarm instead of HPET") defining `use_acpi_alarm' module parameter
even for non-ACPI platforms, which ignore it.  Wrap the definition into
#ifdef CONFIG_ACPI and use a static inline wrapper function, hardcoded
to return 0 and consequently optimized away for !ACPI, following the
existing pattern with HPET handling functions.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Fixes: 311ee9c151 ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET")
Cc: stable@vger.kernel.org # 4.18+
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-10-04 11:15:57 +02:00
Maciej W. Rozycki d197a25385 rtc: cmos: Fix non-ACPI undefined reference to `hpet_rtc_interrupt'
Fix a commit 311ee9c151 ("rtc: cmos: allow using ACPI for RTC alarm
instead of HPET") `rtc-cmos' regression causing a link error:

drivers/rtc/rtc-cmos.o: In function `cmos_platform_probe':
rtc-cmos.c:(.init.text+0x33c): undefined reference to `hpet_rtc_interrupt'
rtc-cmos.c:(.init.text+0x3f4): undefined reference to `hpet_rtc_interrupt'

with non-ACPI platforms using this driver.  The cause is the change of
the condition guarding the use of `hpet_rtc_interrupt'.

Previously it was a call to `is_hpet_enabled'.  That function is static
inline and has a hardcoded 0 result for non-ACPI platforms, which imply
!HPET_EMULATE_RTC.  Consequently the compiler optimized the whole block
away including the reference to `hpet_rtc_interrupt', which never made
it to the link stage.

Now the guarding condition is a call to `use_hpet_alarm', which is not
static inline and therefore the compiler may not be able to prove that
it actually always returns 0 for non-ACPI platforms.  Consequently the
build breaks with an unsatisfied reference, because `hpet_rtc_interrupt'
is nowhere defined at link time.

Fix the problem by marking `use_hpet_alarm' inline.  As the `inline'
keyword serves as an optimization hint rather than a requirement the
compiler is still free to choose whether inlining will be beneficial or
not for ACPI platforms.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Fixes: 311ee9c151 ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET")
Cc: stable@vger.kernel.org # 4.18+
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-10-04 11:15:55 +02:00
Zhang Rui 36d91a4d40 rtc: cmos: introduce quirks to enable use_acpi_alarm mode
Use ACPI for RTC Alarm only for Intel platforms
1. with Low Power S0 support
2. with HPET RTC emulation enabled
3. no earlier than 2015

Note that, during the test, it is found that this patch
1. works in 4.15-rc kernel
2. hangs the platform after suspend-to-idle for 2 or 3 times, in 4.15.0
3. works again in 4.16-rc3 kernel.
4. works in the latest 4.15.12 stable kernel.

Thus although this patch breaks 4.15.0 kernel for some unknown reason,
still, it is safe for both upstream and backport.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-04-19 18:01:50 +02:00
Zhang Rui c6d3a278cc rtc: cmos: acknowledge ACPI driven wake alarms upon resume
Previously, the RTC alarm is acknowledged either by the cmos rtc irq
handler, or by the hpet rtc irq handler.

When using ACPI RTC Fixed event as the RTC alarm, the RTC alarm is
acknowledged by the ACPI RTC event handler, as addressed in the previous
patch.
But, when resume from suspend-to-ram (ACPI S3), the ACPI SCI is cleared
right after resume, thus the ACPI RTC event handler is not invoked at all,
results in the RTC Alarm unacknowledged.

Handle this by comparing the current time and the RTC Alarm time in the
rtc_cmos driver .resume() callback
1. Assume the wakeup event has already been fired if the RTC Alarm time
   is earlier than/equal to the current time, and ACK the RTC Alarm.
2. Assume the wakeup event has not been fired if the RTC Alarm time
   is later than current time, and re-arm it if needed.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-04-19 18:01:50 +02:00
Zhang Rui 311ee9c151 rtc: cmos: allow using ACPI for RTC alarm instead of HPET
It's found that the HPET timer prevents the platform from entering
Low Power S0 on some new Intel platforms.

This means that
1. users can still use RTC wake Alarm for suspend-to-idle, but the system
   never enters Low Power S0, which is a waste of power.
or
2. if users want to put the system into Low Power S0, they can not use
   RTC as the wakeup source.

To fix this, we need to stop using the HPET timer for wake alarm.
But disabling CONFIG_HPET_EMULATE_RTC is not an option because HPET
emulates PIT at the same time, and this is needed on some of these
platforms.

Thus, introduce a new mode (use_acpi_alarm) to the rtc_cmos driver,
so that, even with CONFIG_HPET_EMULATE_RTC enabled, it's still possible to
use ACPI SCI for RTC Alarm, including UIE/AIE/wkalrm, instead of HPET.

Only necessary changes are made for the new "use_acpi_alarm" mode, including
1. drop all the calls to HPET emulation code, including the HPET irq
   handler for rtc interrupt.
2. enabling/disabling ACPI RTC Fixed event upon RTC UIE/AIE request.
3. acknowledge the RTC Alarm in ACPI RTC Fixed event handler.

There is no functional change made in this patch if the new mode is not
enabled.

Note: this "use_acpi_alarm" mode is made based on the assumption that
ACPI RTC Fixed event is reliable both at runtime and during system wakeup.
And this has been verified on a couple of platforms I have, including
a MS Surface Pro 4 (SKL), a Lenovo Yoga 900 (SKL), and a HP 9360 (KBL).

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-04-19 18:01:50 +02:00
Linus Torvalds fbe173e3ff RTC for 4.17
Subsystem:
  - Add tracepoints
  - Rework of the RTC/nvmem API to allow drivers to discard struct nvmem_config
    after registration
  - New range API, drivers can now expose the useful range of the RTC
  - New offset API the core is now able to add an offset to the RTC time,
    modifying the supported range.
  - Multiple rtc_time64_to_tm fixes
  - Handle time_t overflow on 32 bit platforms in the core instead of letting
    drivers do crazy things.
  - remove rtc_control API
 
 New driver:
  - Intersil ISL12026
 
 Drivers:
  - Drivers exposing the RTC non volatile memory have been converted to use nvmem
  - Removed useless time and date validation
  - Removed an indirection pattern that was a cargo cult from ancient drivers
  - Removed VLA usage
  - Fixed a possible race condition in probe functions
  - AB8540 support is dropped from ab8500
  - pcf85363 now has alarm support
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Merge tag 'rtc-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "This contains a few series that have been in preparation for a while
  and that will help systems with RTCs that will fail in 2038, 2069 or
  2100.

  Subsystem:
   - Add tracepoints
   - Rework of the RTC/nvmem API to allow drivers to discard struct
     nvmem_config after registration
   - New range API, drivers can now expose the useful range of the RTC
   - New offset API the core is now able to add an offset to the RTC
     time, modifying the supported range.
   - Multiple rtc_time64_to_tm fixes
   - Handle time_t overflow on 32 bit platforms in the core instead of
     letting drivers do crazy things.
   - remove rtc_control API

  New driver:
   - Intersil ISL12026

  Drivers:
   - Drivers exposing the RTC non volatile memory have been converted to
     use nvmem
   - Removed useless time and date validation
   - Removed an indirection pattern that was a cargo cult from ancient
     drivers
   - Removed VLA usage
   - Fixed a possible race condition in probe functions
   - AB8540 support is dropped from ab8500
   - pcf85363 now has alarm support"

* tag 'rtc-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (128 commits)
  rtc: snvs: Fix usage of snvs_rtc_enable
  rtc: mt7622: fix module autoloading for OF platform drivers
  rtc: isl12022: use true and false for boolean values
  rtc: ab8500: Drop AB8540 support
  rtc: remove a warning during scripts/kernel-doc step
  rtc: 88pm860x: remove artificial limitation
  rtc: 88pm80x: remove artificial limitation
  rtc: st-lpc: remove artificial limitation
  rtc: mrst: remove artificial limitation
  rtc: mv: remove artificial limitation
  rtc: hctosys: Ensure system time doesn't overflow time_t
  parisc: time: stop validating rtc_time in .read_time
  rtc: pcf85063: fix clearing bits in pcf85063_start_clock
  rtc: at91sam9: Set name of regmap_config
  rtc: s5m: Remove VLA usage
  rtc: s5m: Move enum from rtc.h to rtc-s5m.c
  rtc: remove VLA usage
  rtc: Add useful timestamp definitions
  rtc: Add one offset seconds to expand RTC range
  rtc: Factor out the RTC range validation into rtc_valid_range()
  ...
2018-04-10 10:22:27 -07:00
David Howells 739d875dd6 mn10300: Remove the architecture
Remove the MN10300 arch as the hardware is defunct.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Masahiro Yamada <yamada.masahiro@socionext.com>
cc: linux-am33-list@redhat.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-09 23:19:56 +01:00
Alexandre Belloni 812318a094 rtc: cmos: let the core handle invalid time
Setting the rtc to a valid time when the time is invalid is a bad practice,
because then userspace doesn't know it shouldn't trust the RTC.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-01 10:49:39 +01:00
Alexandre Belloni 8b5b7958fd rtc: cmos: use generic nvmem
Instead of adding a binary sysfs attribute from the driver, use the
core to register an nvmem device. This allows to use the in-kernel
interface to access the nvram.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-01 10:49:29 +01:00
Alexandre Belloni 53d29e0a3a rtc: cmos: fix possible race condition
The probe function is not allowed to fail after registering the RTC because
the following may happen:

CPU0:                                CPU1:
sys_load_module()
 do_init_module()
  do_one_initcall()
   cmos_do_probe()
    rtc_device_register()
     __register_chrdev()
     cdev->owner = struct module*
                                     open("/dev/rtc0")
    rtc_device_unregister()
  module_put()
  free_module()
   module_free(mod->module_core)
   /* struct module *module is now
      freed */
                                      chrdev_open()
                                       spin_lock(cdev_lock)
                                       cdev_get()
                                        try_module_get()
                                         module_is_live()
                                         /* dereferences already
                                            freed struct module* */

Switch to devm_rtc_allocate_device/rtc_register_device to register the rtc
as late as possible.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-01 10:49:29 +01:00
Rafael J. Wysocki bb47e96417 Merge branches 'pm-sleep' and 'powercap'
* pm-sleep:
  PM / hibernate: Declare variables as static
  RTC: rtc-cmos: Fix wakeup from suspend-to-idle
  PM / wakeup: Fix up wakeup_source_report_event()

* powercap:
  PowerCap: Fix an error code in powercap_register_zone()
2017-05-22 20:32:05 +02:00
Rafael J. Wysocki 967b08c25a RTC: rtc-cmos: Fix wakeup from suspend-to-idle
Commit eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups from
suspend-to-idle) modified the core suspend-to-idle code to filter
out spurious SCI interrupts received while suspended, which requires
ACPI event source handlers to report wakeup events in a way that
will trigger a wakeup from suspend to idle (or abort system suspends
in progress, which is equivalent).

That needs to be done in the rtc-cmos driver too, which was overlooked
by the above commit, so do that now.

Fixes: eed4d47efe (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle)
Reported-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-05-14 02:23:12 +02:00
Hans de Goede a1e23a42f1 rtc: cmos: Do not assume irq 8 for rtc when there are no legacy irqs
On some systems (e.g. Intel Bay Trail systems) the legacy PIC is not
used, in this case virq 8 will be a random irq, rather then hw_irq 8
from the PIC.

Requesting virq 8 in this case will not help us to get alarm irqs and
may cause problems for other drivers which actually do need virq 8,
for example on an Asus Transformer T100TA this leads to:

[ 28.745155] genirq: Flags mismatch irq 8. 00000088 (mmc0) vs. 00000080 (rtc0)
<snip oops>
[ 28.753700] mmc0: Failed to request IRQ 8: -16
[ 28.975934] sdhci-acpi: probe of 80860F14:01 failed with error -16

This commit fixes this by making the rtc-cmos driver continue
without using an irq rather then claiming irq 8 when no irq is
specified in the pnp-info and there are no legacy-irqs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-04-14 12:08:51 +02:00
Linus Torvalds b0b3a37b90 RTC for 4.10
Subsystem:
  - non-modular drivers are now explicitly non-modular
 
 New driver:
  - Epson Toyocom rtc-7301sf/dg
 
 Drivers:
  - cmos: reject unsupported alarm values wrt the RTC capabilities
  - ds1307: ACPI support
  - jz4740: DT support, jz4780 handling, can now be used as a system power
  controller
  - mcp795: many fixes, in particular proper month handling
  - twl: driver is now DT only
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Merge tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
  "Subsystem:
   - non-modular drivers are now explicitly non-modular

  New driver:
    - Epson Toyocom rtc-7301sf/dg

  Drivers:
   - cmos: reject unsupported alarm values wrt the RTC capabilities
   - ds1307: ACPI support
   - jz4740: DT support, jz4780 handling, can now be used as a system
     power controller
   - mcp795: many fixes, in particular proper month handling
   - twl: driver is now DT only"

* tag 'rtc-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (31 commits)
  rtc: mcp795: Fix whitespace and indentation.
  rtc: mcp795: Prefer using the BIT() macro.
  rtc: mcp795: fix month write resetting date to 1.
  rtc: mcp795: fix time range difference between linux and RTC chip.
  rtc: mcp795: fix bitmask value for leap year (LP).
  rtc: mcp795: use bcd2bin/bin2bcd.
  rtc: add support for EPSON TOYOCOM RTC-7301SF/DG
  rtc: ds1307: Add ACPI support
  rtc: imxdi: (trivial) fix a typo
  rtc: ds1374: Merge conditional + WARN_ON()
  rtc: twl: make driver DT only
  rtc: twl: kill static variables
  rtc: fix typos in Kconfig
  rtc: jz4740: make the driver builtin only
  rtc: jz4740: remove unused EXPORT_SYMBOL
  Documentation: bindings: fix twl-rtc documentation
  rtc: Enable compile testing for Maxim and Samsung drivers
  MIPS: jz4740: Remove obsolete code
  MIPS: qi_lb60: Probe RTC driver from DT and use it as power controller
  MIPS: jz4740: DTS: Probe the jz4740-rtc driver from devicetree
  ...
2016-12-18 18:18:03 -08:00
Linus Torvalds 9465d9cc31 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The time/timekeeping/timer folks deliver with this update:

   - Fix a reintroduced signed/unsigned issue and cleanup the whole
     signed/unsigned mess in the timekeeping core so this wont happen
     accidentaly again.

   - Add a new trace clock based on boot time

   - Prevent injection of random sleep times when PM tracing abuses the
     RTC for storage

   - Make posix timers configurable for real tiny systems

   - Add tracepoints for the alarm timer subsystem so timer based
     suspend wakeups can be instrumented

   - The usual pile of fixes and updates to core and drivers"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  timekeeping: Use mul_u64_u32_shr() instead of open coding it
  timekeeping: Get rid of pointless typecasts
  timekeeping: Make the conversion call chain consistently unsigned
  timekeeping_Force_unsigned_clocksource_to_nanoseconds_conversion
  alarmtimer: Add tracepoints for alarm timers
  trace: Update documentation for mono, mono_raw and boot clock
  trace: Add an option for boot clock as trace clock
  timekeeping: Add a fast and NMI safe boot clock
  timekeeping/clocksource_cyc2ns: Document intended range limitation
  timekeeping: Ignore the bogus sleep time if pm_trace is enabled
  selftests/timers: Fix spelling mistake "Asyncrhonous" -> "Asynchronous"
  clocksource/drivers/bcm2835_timer: Unmap region obtained by of_iomap
  clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map()
  arm64: dts: rockchip: Arch counter doesn't tick in system suspend
  clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend
  posix-timers: Make them configurable
  posix_cpu_timers: Move the add_device_randomness() call to a proper place
  timer: Move sys_alarm from timer.c to itimer.c
  ptp_clock: Allow for it to be optional
  Kconfig: Regenerate *.c_shipped files after previous changes
  ...
2016-12-12 19:56:15 -08:00
Chen Yu ba58d1020a timekeeping: Ignore the bogus sleep time if pm_trace is enabled
Power management suspend/resume tracing (ab)uses the RTC to store
suspend/resume information persistently. As a consequence the RTC value is
clobbered when timekeeping is resumed and tries to inject the sleep time.

Commit a4f8f6667f ("timekeeping: Cap array access in timekeeping_debug")
plugged a out of bounds array access in the timekeeping debug code which
was caused by the clobbered RTC value, but we still use the clobbered RTC
value for sleep time injection into kernel timekeeping, which will result
in random adjustments depending on the stored "hash" value.

To prevent this keep track of the RTC clobbering and ignore the invalid RTC
timestamp at resume. If the system resumed successfully clear the flag,
which marks the RTC as unusable, warn the user about the RTC clobber and
recommend to adjust the RTC with 'ntpdate' or 'rdate'.

[jstultz: Fixed up pr_warn formating, and implemented suggestions from Ingo]
[ tglx: Rewrote changelog ]

Originally-from: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Xunlei Pang <xlpang@redhat.com>
Cc: Len Brown <lenb@kernel.org>
Link: http://lkml.kernel.org/r/1480372524-15181-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-29 18:02:58 +01:00
Ville Syrjälä 368e21aebe rtc: cmos: Don't enable interrupts in the middle of the interrupt handler
Using spin_lock_irq()/spin_unlock_irq() from within the interrupt
handler is a no-no. Let's save/restore the flags to avoid turning on
interrupts prematurely.

We hit this in a bunch of our CI systems, but for whatever reason I
wasn't able to reproduce on my own machine, so this fix is just
based on the backtrace.

[  202.634918] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:2729 trace_hardirqs_on_caller+0x113/0x1b0
[  202.634919] DEBUG_LOCKS_WARN_ON(current->hardirq_context)
[  202.634929] Modules linked in: snd_hda_intel i915 x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel lpc_ich snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_codec snd_hwdep i2c_designware_platform i2c_designware_core snd_hda_core mei_me mei snd_pcm r8169 mii sdhci_acpi sdhci mmc_core i2c_hid [last unloaded: i915]
[  202.634930] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G     U          4.9.0-rc1-CI-CI_DRM_1734+ #1
[  202.634931] Hardware name: GIGABYTE M4HM87P-00/M4HM87P-00, BIOS F6 12/10/2014
[  202.634933]  ffff88011ea03d68 ffffffff8142dce5 ffff88011ea03db8 0000000000000000
[  202.634934]  ffff88011ea03da8 ffffffff8107e496 00000aa900000002 ffffffff81e249a0
[  202.634935]  ffffffff81815637 ffffffff82e7c280 0000000000000000 0000000000000004
[  202.634936] Call Trace:
[  202.634939]  <IRQ>
[  202.634939]  [<ffffffff8142dce5>] dump_stack+0x67/0x92
[  202.634941]  [<ffffffff8107e496>] __warn+0xc6/0xe0
[  202.634944]  [<ffffffff81815637>] ? _raw_spin_unlock_irq+0x27/0x50
[  202.634945]  [<ffffffff8107e4fa>] warn_slowpath_fmt+0x4a/0x50
[  202.634946]  [<ffffffff810d6d83>] trace_hardirqs_on_caller+0x113/0x1b0
[  202.634948]  [<ffffffff810d6e2d>] trace_hardirqs_on+0xd/0x10
[  202.634949]  [<ffffffff81815637>] _raw_spin_unlock_irq+0x27/0x50
[  202.634951]  [<ffffffff81672042>] rtc_handler+0x32/0xa0
[  202.634954]  [<ffffffff814c08a3>] acpi_ev_fixed_event_detect+0xd4/0xfb
[  202.634956]  [<ffffffff814c2ccb>] acpi_ev_sci_xrupt_handler+0xf/0x2d
[  202.634957]  [<ffffffff814ab3ee>] acpi_irq+0x11/0x2c
[  202.634960]  [<ffffffff810e5288>] __handle_irq_event_percpu+0x58/0x370
[  202.634961]  [<ffffffff810e55be>] handle_irq_event_percpu+0x1e/0x50
[  202.634962]  [<ffffffff810e5624>] handle_irq_event+0x34/0x60
[  202.634963]  [<ffffffff810e8906>] handle_fasteoi_irq+0xa6/0x170
[  202.634966]  [<ffffffff8101eef5>] handle_irq+0x15/0x20
[  202.634967]  [<ffffffff8101e548>] do_IRQ+0x68/0x130
[  202.634968]  [<ffffffff81816789>] common_interrupt+0x89/0x89
[  202.634970]  <EOI>
[  202.634970]  [<ffffffff81814c73>] ? mwait_idle+0x93/0x210
[  202.634971]  [<ffffffff81814c6a>] ? mwait_idle+0x8a/0x210
[  202.634972]  [<ffffffff81026b0a>] arch_cpu_idle+0xa/0x10
[  202.634973]  [<ffffffff8181509e>] default_idle_call+0x1e/0x30
[  202.634974]  [<ffffffff810cbf6c>] cpu_startup_entry+0x17c/0x1f0
[  202.634976]  [<ffffffff8180ca87>] rest_init+0x127/0x130
[  202.634978]  [<ffffffff81f77f08>] start_kernel+0x3f6/0x403
[  202.634980]  [<ffffffff81f7728f>] x86_64_start_reservations+0x2a/0x2c
[  202.634981]  [<ffffffff81f77404>] x86_64_start_kernel+0x173/0x186
[  202.634982] ---[ end trace 293c99618fa08d34 ]---

Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Fixes: 983bf1256e ("rtc: cmos: Clear ACPI-driven alarms upon resume")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-10-20 17:40:06 +02:00
Christoph Hellwig 290cd0f07f rtc: cmos: don't refer to asm-generic/rtc.h
That header has been gone for a while.  I've fixed up the Kconfig
comment, but the one in rtc-cmos.c doesn't make any sense to me
even looking at its history.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-10-19 09:41:48 +02:00
Gabriele Mazzotta 6a6af3d044 rtc: cmos: Reject unsupported alarm values
Some platforms allows to specify the month and day of the month in
which an alarm should go off, some others the day of the month and
some others just the time.

Currently any given value is accepted by the driver and only the
supported fields are used to program the hardware. As consequence,
alarms are potentially programmed to go off in the wrong moment.

Fix this by rejecting any unsupported value.

Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-10-19 09:41:43 +02:00
LABBE Corentin a3a0673b9d rtc: cmos: remove all __exit_p annotations
I got the following stack trace under qemu:
[    7.575243] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[    7.596098] IP: [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280
[    7.615699] PGD 3ccbe067
[    7.615923] PUD 3daf2067
[    7.635156] PMD 0
[    7.654358] Oops: 0000 [#1] SMP
[    7.673869] Modules linked in:
[    7.693235] CPU: 0 PID: 1701 Comm: hwclock Tainted: G        W       4.9.0-rc1+ #24
[    7.712455] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
[    7.753569] task: ffff88003d88dc40 task.stack: ffffc90000224000
[    7.773743] RIP: 0010:[<ffffffff814f5b08>]  [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280
[    7.794893] RSP: 0018:ffffc90000227c10  EFLAGS: 00010296
[    7.815890] RAX: 000000000000001d RBX: ffffc90000227d28 RCX: ffffffff8182be78
[    7.836057] RDX: 0000000000000001 RSI: 0000000000000202 RDI: 0000000000000202
[    7.856612] RBP: ffffc90000227c48 R08: 0000000000000000 R09: 0000000000000001
[    7.877561] R10: 00000000000001c0 R11: 00000000000001c0 R12: 0000000000000000
[    7.897072] R13: ffff88003d96f400 R14: ffff88003dac6410 R15: ffff88003dac6420
[    7.917403] FS:  00007f77f42d9700(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
[    7.938293] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    7.958364] CR2: 0000000000000010 CR3: 000000003ccbb000 CR4: 00000000000006f0
[    7.978028] Stack:
[    7.997120]  ffff88003dac6000 ffff88003dac6410 0000000058049d01 ffffc90000227d28
[    8.016993]  ffff88003dac6000 ffff88003dac6410 ffff88003dac6420 ffffc90000227c98
[    8.039505]  ffffffff814f225d 0000001800227c98 000000090000002a 0000000900000011
[    8.059985] Call Trace:
[    8.080110]  [<ffffffff814f225d>] __rtc_set_alarm+0x8d/0xa0
[    8.099421]  [<ffffffff814f2389>] rtc_timer_enqueue+0x119/0x190
[    8.119925]  [<ffffffff814f2e6e>] rtc_update_irq_enable+0xbe/0x100
[    8.140583]  [<ffffffff814f3bb0>] rtc_dev_ioctl+0x3c0/0x480
[    8.161162]  [<ffffffff81146b6a>] ? user_path_at_empty+0x3a/0x50
[    8.182717]  [<ffffffff8114aa36>] do_vfs_ioctl+0x96/0x5c0
[    8.204624]  [<ffffffff8113e066>] ? vfs_stat+0x16/0x20
[    8.225994]  [<ffffffff8113e135>] ? SyS_newstat+0x15/0x30
[    8.247043]  [<ffffffff8114afa7>] SyS_ioctl+0x47/0x80
[    8.267191]  [<ffffffff815f5c77>] entry_SYSCALL_64_fastpath+0x1a/0xa9
[    8.288719] Code: 6a 81 48 89 e5 41 57 41 56 41 55 49 89 fd 41 54 53 48 89 f3 48 c7 c6 20 c4 78 81 48 83 ec 10 e8 8f 00 ef ff 4d 8b a5 a0 00 00 00 <41> 8b 44 24 10 85 c0 0f 8e 2b 02 00 00 4c 89 ef 31 c0 b9 53 01
[    8.335233] RIP  [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280
[    8.357096]  RSP <ffffc90000227c10>
[    8.379051] CR2: 0000000000000010
[    8.401736] ---[ end trace 5cbcd83a1f225ed3 ]---

This occur only when CONFIG_DEBUG_TEST_DRIVER_REMOVE is enabled and
CONFIG_RTC_DRV_CMOS builtin.

When cmos_set_alarm() is called dev is NULL and so trigger the deref via
cmos->irq

The problem comes from that the device is removed but no remove function
are called due to _exit_p().

This patch remove all _exit_p() annotation.

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-10-19 08:45:50 +02:00
Arnd Bergmann 00f7f90c51 rtc: cmos: avoid unused function warning
A bug fix for the ACPI side of this driver caused a harmless
build warning:

drivers/rtc/rtc-cmos.c:1115:13: error: 'cmos_check_acpi_rtc_status' defined but not used [-Werror=unused-function]
 static void cmos_check_acpi_rtc_status(struct device *dev,

We can avoid the warning and simplify the driver at the same time
by removing the #ifdef for CONFIG_PM and rely on the SIMPLE_DEV_PM_OPS()
to set everything up correctly. cmos_resume() has to get marked
as __maybe_unused so we don't introduce another warning, and
the two variants of cmos_poweroff() can get merged into one using
an IS_ENABLED() check.

Fixes: 983bf1256e ("rtc: cmos: Clear ACPI-driven alarms upon resume")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-22 14:23:29 +02:00
Gabriele Mazzotta 68669d55f7 rtc: cmos: Restore alarm after resume
Some platform firmware may interfere with the RTC alarm over suspend,
resulting in the kernel and hardware having different ideas about system
state but also potentially causing problems with firmware that assumes the
OS will clean this case up.  This patch restores the RTC alarm on resume
to ensure that kernel and hardware are in sync.

The case we've seen is Intel Rapid Start, which is a firmware-mediated
feature that automatically transitions systems from suspend-to-RAM to
suspend-to-disk without OS involvement.  It does this by setting the RTC
alarm and a flag that indicates that on wake it should perform the
transition rather than re-starting the OS.  However, if the OS has set a
wakeup alarm that would wake the machine earlier, it refuses to overwrite
it and allows the system to wake instead.

This fails in the following situation:

1) User configures Intel Rapid Start to transition after (say) 15
minutes
2) User suspends to RAM. Firmware sets the wakeup alarm for 15 minutes
in the future
3) User resumes after 5 minutes. Firmware does not reset the alarm, and
as such it is still set for 10 minutes in the future
4) User suspends after 5 minutes. Firmware notices that the alarm is set
for 5 minutes in the future, which is less than the 15 minute transition
threshold. It therefore assumes that the user wants the machine to wake
in 5 minutes
5) System resumes after 5 minutes

The worst case scenario here is that the user may have put the system in a
bag between (4) and (5), resulting in it running in a confined space and
potentially overheating.  This seems reasonably important.  The Rapid
Start support code got added in 3.11, but it can be configured in the
firmware regardless of kernel support.

Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-21 22:09:00 +02:00
Gabriele Mazzotta 983bf1256e rtc: cmos: Clear ACPI-driven alarms upon resume
Currently ACPI-driven alarms are not cleared when they wake the
system. As consequence, expired alarms must be manually cleared to
program a new alarm. Fix this by correctly handling ACPI-driven
alarms.

More specifically, the ACPI specification [1] provides for two
alternative implementations of the RTC. Depending on the
implementation, the driver either clear the alarm from the resume
callback or from ACPI interrupt handler:

 - The platform has the RTC wakeup status fixed in hardware
   (ACPI_FADT_FIXED_RTC is 0). In this case the driver can determine
   if the RTC was the reason of the wakeup from the resume callback
   by reading the RTC status register.

 - The platform has no fixed hardware feature event bits. In this
   case a GPE is used to wake the system and the driver clears the
   alarm from its handler.

[1] http://www.acpi.info/DOWNLOADS/ACPI_5_Errata%20A.pdf

Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-21 22:08:42 +02:00
Pratyush Anand 970fc7f4af rtc: cmos: Initialize hpet timer before irq is registered
We have observed on few x86 machines with rtc-cmos device that
hpet_rtc_interrupt() is called just after irq registration and before
cmos_do_probe() could call hpet_rtc_timer_init().

So, neither hpet_default_delta nor hpet_t1_cmp is initialized by the time
interrupt is raised in the given situation, and this results in NMI
watchdog LOCKUP.

It has only been observed sporadically on kdump secondary kernels.

See the call trace:
---<-snip->---
[   27.913194] Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 0
[   27.915371] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-342.el7.x86_64 #1
[   27.917503] Hardware name: HP ProLiant DL160 Gen8, BIOS J03 02/10/2014
[   27.919455]  ffffffff8186a728 0000000059c82488 ffff880034e05af0 ffffffff81637bd4
[   27.921870]  ffff880034e05b70 ffffffff8163144a 0000000000000010 ffff880034e05b80
[   27.924257]  ffff880034e05b20 0000000059c82488 0000000000000000 0000000000000000
[   27.926599] Call Trace:
[   27.927352]  <NMI>  [<ffffffff81637bd4>] dump_stack+0x19/0x1b
[   27.929080]  [<ffffffff8163144a>] panic+0xd8/0x1e7
[   27.930588]  [<ffffffff8111d3e0>] ? restart_watchdog_hrtimer+0x50/0x50
[   27.932502]  [<ffffffff8111d4a2>] watchdog_overflow_callback+0xc2/0xd0
[   27.934427]  [<ffffffff811612c1>] __perf_event_overflow+0xa1/0x250
[   27.936232]  [<ffffffff81161d94>] perf_event_overflow+0x14/0x20
[   27.937957]  [<ffffffff81032ae8>] intel_pmu_handle_irq+0x1e8/0x470
[   27.939799]  [<ffffffff8164164b>] perf_event_nmi_handler+0x2b/0x50
[   27.941649]  [<ffffffff81640d99>] nmi_handle.isra.0+0x69/0xb0
[   27.943348]  [<ffffffff81640f49>] do_nmi+0x169/0x340
[   27.944802]  [<ffffffff816401d3>] end_repeat_nmi+0x1e/0x2e
[   27.946424]  [<ffffffff81056ee5>] ? hpet_rtc_interrupt+0x85/0x380
[   27.948197]  [<ffffffff81056ee5>] ? hpet_rtc_interrupt+0x85/0x380
[   27.949992]  [<ffffffff81056ee5>] ? hpet_rtc_interrupt+0x85/0x380
[   27.951816]  <<EOE>>  <IRQ>  [<ffffffff8108f5a3>] ? run_timer_softirq+0x43/0x340
[   27.954114]  [<ffffffff8111e24e>] handle_irq_event_percpu+0x3e/0x1e0
[   27.955962]  [<ffffffff8111e42d>] handle_irq_event+0x3d/0x60
[   27.957635]  [<ffffffff811210c7>] handle_edge_irq+0x77/0x130
[   27.959332]  [<ffffffff8101704f>] handle_irq+0xbf/0x150
[   27.960949]  [<ffffffff8164a86f>] do_IRQ+0x4f/0xf0
[   27.962434]  [<ffffffff8163faed>] common_interrupt+0x6d/0x6d
[   27.964101]  <EOI>  [<ffffffff8163f43b>] ? _raw_spin_unlock_irqrestore+0x1b/0x40
[   27.966308]  [<fffff8111ff07>] __setup_irq+0x2a7/0x570
[   28.067859]  [<ffffffff81056e60>] ? hpet_cpuhp_notify+0x140/0x140
[   28.069709]  [<ffffffff8112032c>] request_threaded_irq+0xcc/0x170
[   28.071585]  [<ffffffff814b24a6>] cmos_do_probe+0x1e6/0x450
[   28.073240]  [<ffffffff814b2710>] ? cmos_do_probe+0x450/0x450
[   28.074911]  [<ffffffff814b27cb>] cmos_pnp_probe+0xbb/0xc0
[   28.076533]  [<ffffffff8139b245>] pnp_device_probe+0x65/0xd0
[   28.078198]  [<ffffffff813f8ca7>] driver_probe_device+0x87/0x390
[   28.079971]  [<ffffffff813f9083>] __driver_attach+0x93/0xa0
[   28.081660]  [<ffffffff813f8ff0>] ? __device_attach+0x40/0x40
[   28.083662]  [<ffffffff813f6a13>] bus_for_each_dev+0x73/0xc0
[   28.085370]  [<ffffffff813f86fe>] driver_attach+0x1e/0x20
[   28.086974]  [<ffffffff813f8250>] bus_add_driver+0x200/0x2d0
[   28.088634]  [<ffffffff81ade49a>] ? rtc_sysfs_init+0xe/0xe
[   28.090349]  [<ffffffff813f9704>] driver_register+0x64/0xf0
[   28.091989]  [<ffffffff8139b070>] pnp_register_driver+0x20/0x30
[   28.093707]  [<ffffffff81ade4ab>] cmos_init+0x11/0x71
---<-snip->---

This patch moves hpet_rtc_timer_init() before IRQ registration, so that we
can gracefully handle such spurious interrupts. It also masks HPET RTC
interrupts, in case IRQ registration fails.

We were able to reproduce the problem in maximum 15 trials of kdump
secondary kernel boot on an hp-dl160gen8 FCoE host machine without this
patch.  However, more than 35 trials went fine after applying this patch.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Pratyush Anand <panand@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-09-20 00:22:00 +02:00
Uwe Kleine-König 56d86a7e79 rtc: simplify implementations of read_alarm
Since commit d68778b80d ("rtc: initialize output parameter for read
alarm to "uninitialized"") there is no need to explicitly set
unsupported members to -1. So drop the respective assignments from
drivers.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-07-09 10:24:45 +02:00
Arnd Bergmann 5ee98ab3a8 mn10300: use RTC_DRV_CMOS instead of CONFIG_RTC
nn10300 has a dependency on mc146818_get_time/mc146818_set_time,
which we want to move from the mc146818rtc.h header into the
rtc subsystem, which in turn is not usable on mn10300.

This changes mn10300 to use the modern rtc-cmos driver instead
of the old RTC driver, and that in turn lets us completely
remove the read_persistent_clock/update_persistent_clock callbacks.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-06-26 01:20:08 +02:00
Arnd Bergmann 5ab788d738 rtc: cmos: move mc146818rtc code out of asm-generic/rtc.h
Drivers should not really include stuff from asm-generic directly,
and the PC-style cmos rtc driver does this in order to reuse the
mc146818 implementation of get_rtc_time/set_rtc_time rather than
the architecture specific one for the architecture it gets built for.

To make it more obvious what is going on, this moves and renames the
two functions into include/linux/mc146818rtc.h, which holds the
other mc146818 specific code. Ideally it would be in a .c file,
but that would require extra infrastructure as the functions are
called by multiple drivers with conflicting dependencies.

With this change, the asm-generic/rtc.h header also becomes much
more generic, so it can be reused more easily across any architecture
that still relies on the genrtc driver.

The only caller of the internal __get_rtc_time/__set_rtc_time
functions is in arch/alpha/kernel/rtc.c, and we just change those
over to the new naming.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-06-04 00:20:00 +02:00
Javier Martinez Canillas 6fca3fc516 rtc: Use IS_ENABLED() instead of checking for built-in or module
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either
built-in or as a module, use that macro instead of open coding the same.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-05-20 12:33:51 +02:00
Andy Shevchenko 079062b28f rtc: cmos: prevent kernel warning on IRQ flags mismatch
The Microsoft Surface 3 tablet shares interrupt line between RTC and one of SPI
controllers. However, the rtc_cmos driver doesn't allow shared interrupts and
user sees the following warning

genirq: Flags mismatch irq 8. 00000080 (8086228E:02) vs. 00000000 (rtc0)
...
[<ffffffffa004eb01>] pxa2xx_spi_probe+0x151/0x600 [spi_pxa2xx_platform]

Allow RTC driver to use shared interrupts.

Seems we are on the safe side to do just this simple change since
cmos_interrupt() handler checks for the actual hardware status anyway.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-01-11 20:38:50 +01:00
Vladimir Zapolskiy a3781639e1 rtc: cmos: clean up cmos_nvram_read()/cmos_nvram_write()
The change removes redundant sysfs binary file boundary checks, since
this task is already done on caller side in fs/sysfs/file.c

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:09 +02:00
Adrian Huang 8109d44f76 rtc: cmos: Revert "rtc-cmos: Add an alarm disable quirk"
Commit d5a1c7e3fc ("rtc-cmos: Add an alarm disable quirk") that
added a special quirk is not needed because [PATCH 1/2] of this
patchset makes the kernel more robust:
rtc-cmos: Cancel alarm timer if alarm time is equal to now+1 seconds

Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Tested-by: Egbert Eich <eich@suse.de>
Tested-by: Diego Ercolani <diego.ercolani@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:08 +02:00
Adrian Huang 88b8d33b1c rtc: cmos: Cancel alarm timer if alarm time is equal to now+1 seconds
Steps to reproduce the problem:
	1) Enable RTC wake-up option in BIOS Setup
	2) Issue one of these commands in the OS: "poweroff"
	   or "shutdown -h now"
	3) System will shut down and then reboot automatically

Root-cause of the issue:
	1) During the shutdown process, the hwclock utility is used
	   to save the system clock to hardware clock (RTC).
	2) The hwclock utility invokes ioctl() with RTC_UIE_ON. The
	   kernel configures the RTC alarm for the periodic interrupt
	   (every 1 second).
	3) The hwclock uitlity closes the /dev/rtc0 device, and the
	   kernel disables the RTC alarm irq (AIE bit of Register B)
	   via ioctl() with RTC_UIE_OFF. But, the configured alarm
	   time is the current_time + 1.
	4) After the next 1 second is elapsed, the AF (alarm
	   interrupt flag) of Register C is set.
	5) The S5 handler in BIOS is invoked to configure alarm
	   registers (enable AIE bit and configure alarm date/time).
	   But, BIOS does not clear the previous interrupt status
	   during alarm configuration. Therefore, "AF=AIE=1" causes
	   the rtc device to trigger an interrupt.
	6) So, the machine reboots automatically right after shutdown.

This patch cancels the alarm timer if the following condictions are
met (suggested by Alexandre):
	1) The configured alarm time is equal to current_time + 1
	   seconds.
	2) The AIE timer is not in use.

The member 'alarm_expires' is introduced in struct cmos_rtc because
of the following reasons:
	1) The configured alarm time can be retrieved from
	   cmos_read_alarm(), but we need to take the 'wrapped
	   timestamp' and 'time rollover' into consideration. The
	   function __rtc_read_alarm() eliminates the concerns. To
	   avoid the duplicated code in the lower level RTC driver,
	   invoking __rtc_read_alarm from the lower level RTC driver
	   is not encouraged. Moreover, the compilation error 'the
	   undefined __rtc_read_alarm" is observed if the lower level
	   RTC driver is compiled as a kernel module.
	2) The uie_rtctimer.node.expires and aie_timer.node.expires can
	   be retrieved for the configured alarm time. But, the problem
	   is that either of them might configure the CMOS alarm time.
	   We cannot make sure UIE timer or AIE tiemr configured the
	   CMOS alarm time before. (uie_rtctimer or aie_timer is enabled
	   and then is disabled).
	3) The patch introduces the member 'alarm_expires' to keep the
	   newly configured alarm time, so the above-mentioned concerns
	   can be eliminated.

The issue goes away after 20-time shutdown tests.

Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Tested-by: Egbert Eich <eich@suse.de>
Tested-by: Diego Ercolani <diego.ercolani@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:08 +02:00
Joe Perches a737e835e5 rtc: use more standard kernel logging styles
Neaten the logging a bit by adding #define pr_fmt

Miscellanea:

o Remove __FILE__/__func__ uses
o Coalesce formats adding missing spaces
o Align arguments
o (rtc-cmos) Integrated 2 consecutive messages

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-17 09:04:02 -04:00
Joe Perches 4395eb1f16 rtc: remove use of seq_printf return value
The seq_printf return value, because it's frequently misused,
will eventually be converted to void.

See: commit 1f33c41c03 ("seq_file: Rename seq_overflow() to
     seq_has_overflowed() and make public")

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-04-15 16:35:24 -07:00
Daniel Glöckner a882b14fe8 rtc-cmos: fix wakeup from S5 without CONFIG_PM_SLEEP
Commit b5ada4600d ("drivers/rtc/rtc-cmos.c: fix compilation warning
when !CONFIG_PM_SLEEP") broke wakeup from S5 by making cmos_poweroff a
nop unless CONFIG_PM_SLEEP was defined.

Fix this by restricting the #ifdef to cmos_resume and restoring the old
dependency on CONFIG_PM for cmos_suspend and cmos_poweroff.

Signed-off-by: Daniel Glöckner <daniel-gl@gmx.net>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-14 02:18:19 +02:00
Maciej W. Rozycki 31632dbdba drivers/rtc/rtc-cmos.c: drivers/char/rtc.c features for DECstation support
This brings in drivers/char/rtc.c functionality required for DECstation
and, should the maintainers decide to switch, Alpha systems to use
rtc-cmos.

Specifically these features are made available:

* RTC iomem rather than x86/PCI port I/O mapping, controlled with the
  RTC_IOMAPPED macro as with the original driver.  The DS1287A chip in all
  DECstation systems is mapped in the host bus address space as a
  contiguous block of 64 32-bit words of which the least significant byte
  accesses the RTC chip for both reads and writes.  All the address and
  data window register accesses are made transparently by the chipset glue
  logic so that the device appears directly mapped on the host bus.

* A way to set the size of the address space explicitly with the
  newly-added `address_space' member of the platform part of the RTC
  device structure.  This avoids the unreliable heuristics that does not
  work in a setup where the RTC is not explicitly accessed with the usual
  address and data window register pair.

* The ability to use the RTC periodic interrupt as a system clock
  device, which is implemented by arch/mips/kernel/cevt-ds1287.c for
  DECstation systems and takes the RTC interrupt away from the RTC driver.
   Eventually hooking back to the clock device's interrupt handler should
  be possible for the purpose of the alarm clock and possibly also
  update-in-progress interrupt, but this is not done by this change.

  o To avoid interfering with the clock interrupt all the places where
    the RTC interrupt mask is fiddled with are only executed if and IRQ
    has been assigned to the RTC driver.

  o To avoid changing the clock setup Register A is not fiddled with
    if CMOS_RTC_FLAGS_NOFREQ is set in the newly-added `flags' member of
    the platform part of the RTC device structure.  Originally, in
    drivers/char/rtc.c, this was keyed with the absence of the RTC
    interrupt, just like the interrupt mask, but there only the periodic
    interrupt frequency is set, whereas rtc-cmos also sets the divider
    bits.  Therefore a new flag is introduced so that systems where the
    RTC interrupt is not usable rather than used as a system clock device
    can fully initialise the RTC.

* A small clean-up is made to the IRQ assignment code that makes the IRQ
  number hardcoded to -1 rather than arbitrary -ENXIO (or whatever error
  happens to be returned by platform_get_irq) where no IRQ has been
  assigned to the RTC driver (NO_IRQ might be another candidate, but it
  looks like this macro has inconsistent or missing definitions and
  limited use and might therefore be unsafe).

Verified to work correctly with a DECstation 5000/240 system.

[akpm@linux-foundation.org: fix weird code layout]
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:07 -07:00
Mika Westerberg b5ada4600d drivers/rtc/rtc-cmos.c: fix compilation warning when !CONFIG_PM_SLEEP
CONFIG_PM will be set also if only CONFIG_PM_RUNTIME is set which causes
the compiler to emit following warning:

  drivers/rtc/rtc-cmos.c:845:12: warning: =E2=80=98cmos_resume=E2=80=99 defined but not used [-Wunused-function]

Fix this by using CONFIG_PM_SLEEP instead of CONFIG_PM and removing it
from the driver pm ops as this has been taken care by
SIMPLE_DEV_PM_OPS() already.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:21 -07:00
Andrew Morton 24b34472e2 drivers/rtc/rtc-cmos.c: propagate hpet_register_irq_handler() failure
If hpet_register_irq_handler() fails, cmos_do_probe() will incorrectly
return 0.

Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:37:00 -08:00
Geert Uytterhoeven c823a20244 drivers/rtc/rtc-cmos.c: remove superfluous name cast
device_driver.name is "const char *"

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23 16:36:59 -08:00
Borislav Petkov d5a1c7e3fc rtc-cmos: Add an alarm disable quirk
41c7f74242 ("rtc: Disable the alarm in the hardware (v2)") added the
functionality to disable the RTC wake alarm when shutting down the box.

However, there are at least two b0rked BIOSes we know about:

https://bugzilla.novell.com/show_bug.cgi?id=812592
https://bugzilla.novell.com/show_bug.cgi?id=805740

where, when wakeup alarm is enabled in the BIOS, the machine reboots
automatically right after shutdown, regardless of what wakeup time is
programmed.

Bisecting the issue lead to this patch so disable its functionality with
a DMI quirk only for those boxes.

Cc: Brecht Machiels <brecht@mos6581.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
[jstultz: Changed variable name for clarity, added extra dmi entry]
Tested-by: Brecht Machiels <brecht@mos6581.org>
Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-12-23 12:52:20 -08:00
Jingoo Han 97a92e77ca drivers/rtc/rtc-cmos.c: use dev_get_platdata()
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.  This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:28 +09:00