Commit Graph

866 Commits

Author SHA1 Message Date
Linus Torvalds
79016f6488 Merge branch 'timers-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip
* 'timers-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
  rtc: twl: Fix registration vs. init order
  rtc: Initialized rtc_time->tm_isdst
  rtc: Fix RTC PIE frequency limit
  rtc: rtc-twl: Remove lockdep related local_irq_enable()
  rtc: rtc-twl: Switch to using threaded irq
  rtc: ep93xx: Fix 'rtc' may be used uninitialized warning
  alarmtimers: Avoid possible denial of service with high freq periodic timers
  alarmtimers: Memset itimerspec passed into alarm_timer_get
  alarmtimers: Avoid possible null pointer traversal
2011-09-07 13:03:48 -07:00
Todd Poynor
7e72c68634 rtc: twl: Fix registration vs. init order
Only register as an RTC device after the hardware has been
successfully initialized.  The RTC class driver will call
back to this driver to read a pending alarm, and other
drivers watching for new devices on the RTC class may
read the RTC time upon registration.  Such access might
occur while the RTC is stopped, prior to clearing
pending alarms, etc.

The new ordering also avoids leaving the platform
device drvdata set to an unregistered struct rtc_device *
on probe errors.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-26 17:26:54 -07:00
Mike Waychison
a7402deb32 rtc: Initialized rtc_time->tm_isdst
Even though the Linux kernel does not use the tm_isdst field, it is
exposed as part of the ABI.  This field can accidentally be left
initialized, which is why we currently memset buffers returned to
userland in rtc_read_time.

There is a case however where the field can return garbage from the
stack though when using the RTC_ALM_READ ioctl on the rtc device.  This
ioctl invokes rtc_read_alarm, which is careful to memset the rtc_wkalrm
buffer that is copied to userland, but it then uses a struct copy to
assign to alarm->time given the return value from rtc_ktime_to_tm().

rtc_ktime_to_tm() is implemented by calling rtc_time_to_tm using a
derivative seconds counds from ktime, but rtc_time_to_tm does not assign
a value to ->tm_isdst.  This results in garbage from rtc_ktime_to_tm()'s
frame ending up being copied out to userland as part of the returned
rtc_wkalrm.

Fix this by initializing rtc_time->tm_isdst to 0 in rtc_time_to_tm.

Signed-off-by: Mike Waychison <mikew@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-26 17:26:35 -07:00
MyungJoo Ham
62d1760180 drivers/rtc/rtc-s3c.c: allow multiple open / allow no-ioctl-open'ed rtc to have irq.
The previous rtc-s3c had two issues related with its IRQ.

1. Users cannot open rtc multiple times because an open operation
   calls request_irq on the same IRQ.  (e.g., two user processes wants to
   open and read RTC time from rtc-s3c at the same time)

2. If alarm is set and no one has the rtc opened with filesystem
   (either the alarm is set by kernel/boot-loader or user set an alarm and
   closed rtc dev file), the pending bit is not cleared and no further
   interrupt is invoked.  When the alarm is used by the system itself such
   as a resume from suspend-to-RAM or other Low-power modes/idle, this is
   a critical issue.

This patch mitigates these issues by calling request_irq at probe and
free_irq at remove.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Changhwan Youn <chaos.youn@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25 18:51:00 -07:00
MyungJoo Ham
4e8896cde1 drivers/rtc/rtc-s3c.c: correct debug messages
RTC-S3C used to print out debug messages incorrectly.  This patch
corrects incorrect outputs.  (undecoded bcd numbers, incorrectly decoded
register values)

This patch affects the pr-debug messages only.

Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Changhwan Youn <chaos.youn@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-25 18:50:43 -07:00
Linus Torvalds
6cac952960 Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rtc: Limit RTC PIE frequency
  rtc: Fix hrtimer deadlock
  rtc: Handle errors correctly in rtc_irq_set_state()

Fixup trivial conflicts in drivers/rtc/interface.c due to slightly
trivially versions of the same patch coming in two different ways.
2011-08-17 10:28:33 -07:00
John Stultz
938f97bcf1 rtc: Fix RTC PIE frequency limit
Thomas earlier submitted a fix to limit the RTC PIE freq, but
picked 5000Hz out of the air. Willy noticed that we should
instead use the 8192Hz max from the rtc man documentation.

Cc: Willy Tarreau <w@1wt.eu>
Cc: stable@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-10 15:55:12 -07:00
Sebastian Reichel
34d623d113 rtc: rtc-twl: Remove lockdep related local_irq_enable()
Now that the irq is properly threaded (due to it needing i2c access)
we should also remove the local_irq_enable() call in twl_rtc_interrupt.
Testing this with Pandaboard, the RTC is still working.

[Reworked commit message -jstultz]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-10 15:54:26 -07:00
Ilkka Koskinen
dec35d19c4 rtc: rtc-twl: Switch to using threaded irq
The driver is accessing to i2c bus in interrupt handler.
Therefore, it should use threaded irq.

Signed-off-by: Ilkka Koskinen <ilkka.koskinen@nokia.com>
Acked-by: Balaji T K <balajitk@ti.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-10 15:54:25 -07:00
Axel Lin
bf6ed027bc rtc: ep93xx: Fix 'rtc' may be used uninitialized warning
commit 92d921c5d "rtc: ep93xx: Initialize drvdata before registering device"
ensures the drvdata is initialized prior to registering the rtc device.
But it set the drvdata to an uninitialized pointer.
Thus calling platform_get_drvdata in ep93xx_rtc_remove does not get correct address.

This patch fixes below warning by adding struct rtc_device *rtc to struct ep93xx_rtc.
Then set platform drvdata to ep93xx_rtc instead of rtc.

  CC      drivers/rtc/rtc-ep93xx.o
drivers/rtc/rtc-ep93xx.c: In function 'ep93xx_rtc_probe':
drivers/rtc/rtc-ep93xx.c:154: warning: 'rtc' may be used uninitialized in this function

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-08-10 15:54:24 -07:00
Daniel Glöckner
12b3e038e5 rtc-omap: fix initialization of control register
As the comment explains, the intention of the code is to clear the
OMAP_RTC_CTRL_MODE_12_24 bit, but instead it only clears the
OMAP_RTC_CTRL_SPLIT and OMAP_RTC_CTRL_AUTO_COMP bits, which should be
kept.  OMAP_RTC_CTRL_DISABLE, OMAP_RTC_CTRL_SET_32_COUNTER,
OMAP_RTC_CTRL_TEST, and OMAP_RTC_CTRL_ROUND_30S are also better off
being cleared.

Signed-off-by: Daniel Glöckner <dg@emlix.com>
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>
2011-08-03 14:25:20 -10:00
Thomas Gleixner
b830ac1d9a rtc: fix hrtimer deadlock
Ben reported a lockup related to rtc. The lockup happens due to:

CPU0                                        CPU1

rtc_irq_set_state()			    __run_hrtimer()
  spin_lock_irqsave(&rtc->irq_task_lock)    rtc_handle_legacy_irq();
					      spin_lock(&rtc->irq_task_lock);
  hrtimer_cancel()
    while (callback_running);

So the running callback never finishes as it's blocked on
rtc->irq_task_lock.

Use hrtimer_try_to_cancel() instead and drop rtc->irq_task_lock while
waiting for the callback.  Fix this for both rtc_irq_set_state() and
rtc_irq_set_freq().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Ben Greear <greearb@candelatech.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:42 -07:00
Thomas Gleixner
431e2bcc37 rtc: limit frequency
Due to the hrtimer self rearming mode a user can DoS the machine simply
because it's starved by hrtimer events.

The RTC hrtimer is self rearming.  We really need to limit the frequency
to something sensible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ben Greear <greearb@candelatech.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:42 -07:00
Thomas Gleixner
2c4f57d12d rtc: handle errors correctly in rtc_irq_set_state()
The code checks the correctness of the parameters, but unconditionally
arms/disarms the hrtimer.

The result is that a random task might arm/disarm rtc timer and surprise
the real owner by either generating events or by stopping them.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ben Greear <greearb@candelatech.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:41 -07:00
Thomas Gleixner
6e7a333eaa rtc: Limit RTC PIE frequency
The RTC pie hrtimer is self rearming. We really need to limit the
frequency to something sensible. Thus limit it to the 8192Hz max
value from the rtc man documentation

Cc: Willy Tarreau <w@1wt.eu>
Cc: stable@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[jstultz: slightly reworked to use RTC_MAX_FREQ value]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-26 14:50:01 -07:00
Thomas Gleixner
3c8bb90efb rtc: Fix hrtimer deadlock
Ben reported a lockup related to rtc. The lockup happens due to:

CPU0                                        CPU1

rtc_irq_set_state()			    __run_hrtimer()
  spin_lock_irqsave(&rtc->irq_task_lock)    rtc_handle_legacy_irq();
					      spin_lock(&rtc->irq_task_lock);
  hrtimer_cancel()
    while (callback_running);

So the running callback never finishes as it's blocked on
rtc->irq_task_lock.

Use hrtimer_try_to_cancel() instead and drop rtc->irq_task_lock while
waiting for the callback. Fix this for both rtc_irq_set_state() and
rtc_irq_set_freq().

Cc: stable@kernel.org
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-26 14:49:59 -07:00
Thomas Gleixner
53cc2820ac rtc: Handle errors correctly in rtc_irq_set_state()
In rtc_irq_set_state, the code checks the correctness of the parameters,
but then goes on to unconditionally arms/disarms the hrtimer. Thus a
random task might arm/disarm rtc timer and surprise the real owner by
either generating events or by stopping them.

Cc: stable@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-26 14:49:57 -07:00
Linus Torvalds
45b583b10a Merge 'akpm' patch series
* Merge akpm patch series: (122 commits)
  drivers/connector/cn_proc.c: remove unused local
  Documentation/SubmitChecklist: add RCU debug config options
  reiserfs: use hweight_long()
  reiserfs: use proper little-endian bitops
  pnpacpi: register disabled resources
  drivers/rtc/rtc-tegra.c: properly initialize spinlock
  drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in twl_rtc_set_time()
  drivers/rtc: add support for Qualcomm PMIC8xxx RTC
  drivers/rtc/rtc-s3c.c: support clock gating
  drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200
  init: skip calibration delay if previously done
  misc/eeprom: add eeprom access driver for digsy_mtc board
  misc/eeprom: add driver for microwire 93xx46 EEPROMs
  checkpatch.pl: update $logFunctions
  checkpatch: make utf-8 test --strict
  checkpatch.pl: add ability to ignore various messages
  checkpatch: add a "prefer __aligned" check
  checkpatch: validate signature styles and To: and Cc: lines
  checkpatch: add __rcu as a sparse modifier
  checkpatch: suggest using min_t or max_t
  ...

Did this as a merge because of (trivial) conflicts in
 - Documentation/feature-removal-schedule.txt
 - arch/xtensa/include/asm/uaccess.h
that were just easier to fix up in the merge than in the patch series.
2011-07-25 21:00:19 -07:00
Uwe Kleine-König
e57ee01750 drivers/rtc/rtc-tegra.c: properly initialize spinlock
Using __SPIN_LOCK_UNLOCKED for a dynamically allocated lock is wrong and
breaks the build with PREEMPT_RT_FULL.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Andrew Chew <achew@nvidia.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:17 -07:00
Jesper Juhl
8f6b0dd369 drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in twl_rtc_set_time()
We forget to save the return value of the call to
twl_rtc_write_u8(save_control, REG_RTC_CTRL_REG); in 'ret', making the
test of 'ret < 0' dead code since 'ret' then couldn't possibly have
changed since the last test just a few lines above.  It also makes us not
detect failures from that specific twl_rtc_write_u8() call.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Rusev <source@mvista.com>
Cc: "George G. Davis" <gdavis@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:17 -07:00
Anirudh Ghayal
9a9a54ad7a drivers/rtc: add support for Qualcomm PMIC8xxx RTC
Add support for PMIC8xxx based RTC.  PMIC8xxx is Qualcomm's power
management IC that internally houses an RTC module.  This driver
communicates with the PMIC module over SSBI bus.

[akpm@linux-foundation.org: cosmetic tweaks]
Acked-by: Wan ZongShun <mcuos.com@gmail.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
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>
2011-07-25 20:57:17 -07:00
Donggeun Kim
cefe4fbbaa drivers/rtc/rtc-s3c.c: support clock gating
Add support for clock gating.  Power consumption can be reduced by setting
rtc_clk disabled state except for when RTC related registers are accessed.

Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: KyungMin Park <kyungmin.park@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Ben Dooks <ben@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:17 -07:00
Dmitry Eremin-Solenikov
955dbea3c7 drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200
MPC5200B contains a limited version of RTC from MPC5121.  Add support for
the RTC on that CPU.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-25 20:57:17 -07:00
Linus Torvalds
d3ec4844d4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (43 commits)
  fs: Merge split strings
  treewide: fix potentially dangerous trailing ';' in #defined values/expressions
  uwb: Fix misspelling of neighbourhood in comment
  net, netfilter: Remove redundant goto in ebt_ulog_packet
  trivial: don't touch files that are removed in the staging tree
  lib/vsprintf: replace link to Draft by final RFC number
  doc: Kconfig: `to be' -> `be'
  doc: Kconfig: Typo: square -> squared
  doc: Konfig: Documentation/power/{pm => apm-acpi}.txt
  drivers/net: static should be at beginning of declaration
  drivers/media: static should be at beginning of declaration
  drivers/i2c: static should be at beginning of declaration
  XTENSA: static should be at beginning of declaration
  SH: static should be at beginning of declaration
  MIPS: static should be at beginning of declaration
  ARM: static should be at beginning of declaration
  rcu: treewide: Do not use rcu_read_lock_held when calling rcu_dereference_check
  Update my e-mail address
  PCIe ASPM: forcedly -> forcibly
  gma500: push through device driver tree
  ...

Fix up trivial conflicts:
 - arch/arm/mach-ep93xx/dma-m2p.c (deleted)
 - drivers/gpio/gpio-ep93xx.c (renamed and context nearby)
 - drivers/net/r8169.c (just context changes)
2011-07-25 13:56:39 -07:00
Linus Torvalds
52de84f3f3 Merge branch 'timers-rtc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-rtc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Serialize EFI time accesses on rtc_lock
  x86: Serialize SMP bootup CMOS accesses on rtc_lock
  rtc: stmp3xxx: Remove UIE handlers
  rtc: stmp3xxx: Get rid of mach-specific accessors
  rtc: stmp3xxx: Initialize drvdata before registering device
  rtc: stmp3xxx: Port stmp-functions to mxs-equivalents
  rtc: stmp3xxx: Restore register definitions
  rtc: vt8500: Use define instead of hardcoded value for status bit
2011-07-22 16:52:39 -07:00