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2011-09-07Merge branch 'timers-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tipLinus Torvalds
* '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
2011-08-26rtc: twl: Fix registration vs. init orderTodd Poynor
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>
2011-08-26rtc: Initialized rtc_time->tm_isdstMike Waychison
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>
2011-08-25drivers/rtc/rtc-s3c.c: allow multiple open / allow no-ioctl-open'ed rtc to ↵MyungJoo Ham
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>
2011-08-25drivers/rtc/rtc-s3c.c: correct debug messagesMyungJoo Ham
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>
2011-08-17Merge branch 'timers-fixes-for-linus' of ↵Linus Torvalds
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.
2011-08-10rtc: Fix RTC PIE frequency limitJohn Stultz
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>
2011-08-10rtc: rtc-twl: Remove lockdep related local_irq_enable()Sebastian Reichel
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>
2011-08-10rtc: rtc-twl: Switch to using threaded irqIlkka Koskinen
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>
2011-08-10rtc: ep93xx: Fix 'rtc' may be used uninitialized warningAxel Lin
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>
2011-08-03rtc-omap: fix initialization of control registerDaniel Glöckner
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>
2011-07-26rtc: fix hrtimer deadlockThomas Gleixner
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>
2011-07-26rtc: limit frequencyThomas Gleixner
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>
2011-07-26rtc: handle errors correctly in rtc_irq_set_state()Thomas Gleixner
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>
2011-07-26rtc: Limit RTC PIE frequencyThomas Gleixner
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>
2011-07-26rtc: Fix hrtimer deadlockThomas Gleixner
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>
2011-07-26rtc: Handle errors correctly in rtc_irq_set_state()Thomas Gleixner
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>
2011-07-25Merge 'akpm' patch seriesLinus Torvalds
* 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.
2011-07-25drivers/rtc/rtc-tegra.c: properly initialize spinlockUwe Kleine-König
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>
2011-07-25drivers/rtc/rtc-twl.c: check return value of twl_rtc_write_u8() in ↵Jesper Juhl
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>
2011-07-25drivers/rtc: add support for Qualcomm PMIC8xxx RTCAnirudh Ghayal
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>
2011-07-25drivers/rtc/rtc-s3c.c: support clock gatingDonggeun Kim
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>
2011-07-25drivers/rtc/rtc-mpc5121.c: add support for RTC on MPC5200Dmitry Eremin-Solenikov
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>
2011-07-25Merge branch 'for-linus' of ↵Linus Torvalds
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)
2011-07-22Merge branch 'timers-rtc-for-linus' of ↵Linus Torvalds
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
2011-07-22Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: time: Fix stupid KERN_WARN compile issue rtc: Avoid accumulating time drift in suspend/resume time: Avoid accumulating time drift in suspend/resume time: Catch invalid timespec sleep values in __timekeeping_inject_sleeptime
2011-07-11Merge branch 'master' into for-nextJiri Kosina
Sync with Linus' tree to be able to apply pending patches that are based on newer code already present upstream.
2011-07-01rtc: stmp3xxx: Remove UIE handlersWolfram Sang
The RTC core handles UIE since 6610e08 (RTC: Rework RTC code to use timerqueue for events), so remove the specific interrupt in this driver. To make it work at all, enable interrupts in set_alarm() if needed. Drop IRQF_DISABLED which is deprecated, while we are here. Finally, add my copyright after all these changes. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Tested-by: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-01rtc: stmp3xxx: Get rid of mach-specific accessorsWolfram Sang
Replace the accessors with standard readl/writel to remove their platform-dependency. Also, drop __raw_(read|write)l-accessors while we are here. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Tested-by: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-01rtc: stmp3xxx: Initialize drvdata before registering deviceWolfram Sang
Commit f44f7f96a20 ("RTC: Initialize kernel state from RTC") uncovered an issue in a number of RTC drivers, where the drivers call rtc_device_register before initializing the device or platform drvdata. This frequently results in null pointer dereferences when the rtc_device_register immediately makes use of the rtc device, calling rtc_read_alarm. The solution is to ensure the drvdata is initialized prior to registering the rtc device. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Tested-by: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-01rtc: stmp3xxx: Port stmp-functions to mxs-equivalentsWolfram Sang
The stmp3xxx driver used to include functions from a stmp-specific include. Because of consolidation, plat-stmp has now been removed and merged with the compatible mach-mxs. Use the apropriate mxs-functions for transition. The accessors will be converted to readl/writel in a later patch. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Tested-by: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-01rtc: stmp3xxx: Restore register definitionsWolfram Sang
The stmp3xxx driver used to include register names from a stmp-specific include. Because of consolidation, plat-stmp has now been removed and merged with the compatible mach-mxs. Restore the register names directly in the driver and rename them to be specific to this driver. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Tested-by: Shawn Guo <shawn.guo@freescale.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-07-01rtc: vt8500: Use define instead of hardcoded value for status bitWolfram Sang
Fixes the vt8500 driver to use a define value for the isr is-alarm bit. Cc: Alexey Charkov <alchark@gmail.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-06-27drivers/rtc/rtc-ds1307.c: add support for RTC device pt7c4338Priyanka Jain
PT7C4338 chip is being manufactured by Pericom Technology Inc. It is a serial real-time clock which provides: 1) Low-power clock/calendar. 2) Programmable square-wave output. It has 56 bytes of nonvolatile RAM. Its register set is same as that of rtc device: DS1307. Signed-off-by: Priyanka Jain <Priyanka.Jain@freescale.com> Acked-by: Timur Tabi <timur@freescale.com> Reviewed-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-23rtc: vt8500: Fix build error & cleanup rtc_class_ops->update_irq_enable()Alexey Charkov
Now that the generic code handles UIE mode irqs via periodic alarm interrupts, no one calls the rtc_class_ops->update_irq_enable() method anymore. Further the rtc_class_ops doesn't have a update_irq_enable element anymore, so this causes a build error. This patch removes the driver hooks and implementations of update_irq_enable and the associated setup. [wsa: updated commit-message and removed update_irq_enable-function, too] [jstultz: improve commit message, clarifying build issue] Signed-off-by: Alexey Charkov <alchark@gmail.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-06-21rtc: Avoid accumulating time drift in suspend/resumeJohn Stultz
Because the RTC interface is only a second granular interface, each time we read from the RTC for suspend/resume, we introduce a half second (on average) of error. In order to avoid this error accumulating as the system is suspended over and over, this patch measures the time delta between the RTC and the system CLOCK_REALTIME. If the delta is less then 2 seconds from the last suspend, we compensate by using the previous time delta (keeping it close). If it is larger then 2 seconds, we assume the clock was set or has been changed, so we do no correction and update the delta. Note: If NTP is running, ths could seem to "fight" with the NTP corrected time, where as if the system time was off by 1 second, and NTP slewed the value in, a suspend/resume cycle could undo this correction, by trying to restore the previous offset from the RTC. However, without this patch, since each read could cause almost a full second worth of error, its possible to get almost 2 seconds of error just from the suspend/resume cycle alone, so this about equal to any offset added by the compensation. Further on systems that suspend/resume frequently, this should keep time closer then NTP could compensate for if the errors were allowed to accumulate. Credits to Arve Hjønnevåg for suggesting this solution. This patch also improves some of the variable names and adds more clear comments. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-06-13Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rtc: Staticize non-exported __rtc_set_alarm() rtc: Fix ioctl error path return ptp: Fix some locking bugs in ptp_read() ptp: Return -EFAULT on copy_to_user() errors
2011-06-10treewide: Convert uses of struct resource to resource_size(ptr)Joe Perches
Several fixes as well where the +1 was missing. Done via coccinelle scripts like: @@ struct resource *ptr; @@ - ptr->end - ptr->start + 1 + resource_size(ptr) and some grep and typing. Mostly uncompiled, no cross-compilers. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-06-09unicore32: move rtc-puv3.c to drivers/rtc directoryGuan Xuetao
The patch moves rtc driver for PKUnity-v3 SoC from arch/unicore32/kernel/ to drivers/rtc/, with renaming it to rtc-puv3.c. Also, Kconfig, Makefile, and MAINTAINERS are modified correspondingly. Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn> Acked-by: Arnd Bergmann <arnd@arndb.de>
2011-06-08spi/rtc-m41t93: Use spi_get_drvdata() for SPI devicesGeert Uytterhoeven
One new offender detected by the recently increased type checking in platform_get_drvdata(): drivers/rtc/rtc-m41t93.c: In function ‘m41t93_remove’: drivers/rtc/rtc-m41t93.c:192: warning: passing argument 1 of ‘platform_get_drvdata’ from incompatible pointer type Use spi_get_drvdata() instead of platform_get_drvdata(), cfr. commit 42fea15d6dc410e62dac6a764142045280624a5b ("spi/rtc-{ds1390,ds3234,m41t94}: Use spi_get_drvdata() for SPI devices") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-06-01rtc: Staticize non-exported __rtc_set_alarm()Mark Brown
It's not referenced outside this file so there's no need for it to be in the global namespace and sparse warns about that. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-06-01rtc: Fix ioctl error path returnJohn Stultz
Bryan Henderson noticed that the "RTC: Fix rtc driver ioctl specific shortcutting" commit has a small bug: When an ioctl is called with an invalid command code and the clock driver does not have an "ioctl" method, the ioctl returns rc 0 instead of -ENOTTY. This patch fixes the issue. CC: Bryan Henderson <bryanh@giraffe-data.com> CC: Gabor Z. Papp <gzp@papp.hu> Reported-by: Bryan Henderson <bryanh@giraffe-data.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2011-05-26drivers/rtc/rtc-mxc.c: remove defines already included in rtc.hWolfram Sang
[akpm@linux-foundation.org: retain the code comments] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Cc: Vladimir Zapolskiy <vzapolskiy@gmail.com> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26drivers/rtc/rtc-pcf50633.c: don't request update IRQLars-Peter Clausen
Commit 51ba60c5 ("RTC: Cleanup rtc_class_ops->update_irq_enable()") removed the only user of the update IRQ, so there is no need to manage it any more. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26rtc: add support for spear rtcRajeev Kumar
Signed-off-by: Rajeev Kumar <rajeev-dlh.kumar@st.com> Signed-off-by: Viresh Kumar <viresh.kumar@st.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>
2011-05-26drivers/rtc/rtc-mrst.c: use release_mem_region after request_mem_regionJulia Lawall
The memory allocated using request_mem_region should be released using release_mem_region, not release_region. The semantic patch that fixes part of this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression E1,E2,E3; @@ request_mem_region(E1,E2,E3) ... ?- release_region(E1,E2) + release_mem_region(E1,E2) // </smpl> [akpm@linux-foundation.org: use resource_size()] Signed-off-by: Julia Lawall <julia@diku.dk> 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>
2011-05-26rtc: add basic support for ST M41T93 SPI RTCVoss, Nikolaus
Add basic support for ST m41t93 SPI RTCs. Tested with factory-new and with "run-in" species with and without backup batteries. Signed-off-by: Nikolaus Voss <n.voss@weinmann.de> Cc: Alessandro Zummo <a.zummo@towertech.it> 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>
2011-05-26rtc: add rv3029c2 RTC supportHeiko Schocher
Add support for the Micro Crystal RV3029-C2 RTC chips. Signed-off-by: Heiko Schocher <hs@denx.de> Signed-off-by: Gregory Hermant <gregory.hermant@calao-systems.com> Cc: Wan ZongShun <mcuos.com@gmail.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26rtc: add EM3027 rtc driverMike Rapoport
Add support for EM Microelectronic EM3027 RTC chip. Signed-off-by: Mike Rapoport <mike@compulab.co.il> 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>
2011-05-26rtc: add support for the RTC in VIA VT8500 and compatiblesAlexey Charkov
This adds a driver for the RTC devices in VIA and WonderMedia Systems-on-Chip. Alarm, 1Hz interrupts, reading and setting time are supported. Signed-off-by: Alexey Charkov <alchark@gmail.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Alexey Charkov <alchark@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>