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path: root/drivers/rtc/class.c (follow)
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* rtc: class: remove redundant assignment to variable errColin Ian King2020-04-021-1/+1
| | | | | | | | | | | The variable err is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Link: https://lore.kernel.org/r/20200402110411.508534-1-colin.king@canonical.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: class: avoid unnecessary lookup in hctosysAlexandre Belloni2020-03-241-14/+2
| | | | | | | | rtc_hctosys is only called when the relevant RTC is found, avoid looking it up while we already have a pinter to the proper struct rtc_device. Link: https://lore.kernel.org/r/20200323213039.297458-1-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: class: support hctosys from modular RTC driversSteve Muckle2020-03-231-0/+61
| | | | | | | | | | | | | Due to distribution constraints it may not be possible to statically compile the required RTC driver into the kernel. Expand RTC_HCTOSYS support to cover all RTC devices (statically compiled or not) by checking at the end of RTC device registration whether the time should be synced. Signed-off-by: Steve Muckle <smuckle@google.com> Link: https://lore.kernel.org/r/20191106194625.116692-1-smuckle@google.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: class: add debug message when registration failsAlexandre Belloni2019-08-201-1/+3
| | | | | | | | | | Add a message when __rtc_register_device fails because rtc->ops is NULL. This may only happen when developing a new driver so use dev_dbg to avoid compiling it in by default. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lore.kernel.org/r/20190818220041.17833-1-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: core: correct trivial checkpatch warningsAlexandre Belloni2019-04-041-8/+6
| | | | | | | Correct trivial checkpatch warnings, mostly whitespace issues and unbalanced braces. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: convert core to SPDX identifierAlexandre Belloni2019-03-181-5/+2
| | | | | | | Use SPDX-License-Identifier instead of a verbose license text. Also fix the block comment alignment. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: class: reimplement devm_rtc_device_registerAlexandre Belloni2018-12-181-121/+36
| | | | | | | | | | | | Implement devm_rtc_device_register using devm_rtc_allocate_device and __rtc_register_device so there is only one path left to register rtc devices. Also mark it as deprecated so new drivers will hopefully use devm_rtc_allocate_device and rtc_register_device that are less race prone and allow avoiding the 2038, 2070, 2100 and 2106 bugs properly. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: enforce rtc_timer_init private_data typeAlexandre Belloni2018-12-181-2/+2
| | | | | | | | All the remaining users of rtc_timers are passing the rtc_device as private data. Enforce that and rename private_data to rtc. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: class: remove devm_rtc_device_unregisterAlexandre Belloni2018-11-121-26/+0
| | | | | | | devm_rtc_device_unregister is not used by any driver and should not be used by any new driver. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: unexport non devm managed registrationAlexandre Belloni2018-09-131-7/+5
| | | | | | | Ensure the non managed version of the un/registration functions is not used anymore. No driver is using it anymore and they should not be necessary. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: remove irq_task and irq_task_lockAlexandre Belloni2018-07-261-1/+0
| | | | | | | There is no way to set a periodic task anymore, remove task pointer and lock. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: use ktime_get_real_ts64() instead of getnstimeofday64()Arnd Bergmann2018-07-131-2/+2
| | | | | | | | | | | | | getnstimeofday64() is just a wrapper around the ktime accessor, so we should use that directly. I considered using ktime_get_boottime_ts64() (to avoid leap second problems) or ktime_get_real_seconds() (to simplify the calculation, but in the end concluded that the existing interface is probably the most appropriate in this case. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: Add one offset seconds to expand RTC rangeBaolin Wang2018-03-171-0/+70
| | | | | | | | | | | | | | | | | | | | | | From our investigation for all RTC drivers, 1 driver will be expired before year 2017, 7 drivers will be expired before year 2038, 23 drivers will be expired before year 2069, 72 drivers will be expired before 2100 and 104 drivers will be expired before 2106. Especially for these early expired drivers, we need to expand the RTC range to make the RTC can still work after the expired year. So we can expand the RTC range by adding one offset to the time when reading from hardware, and subtracting it when writing back. For example, if you have an RTC that can do 100 years, and currently is configured to be based in Jan 1 1970, so it can represents times from 1970 to 2069. Then if you change the start year from 1970 to 2000, which means it can represents times from 2000 to 2099. By adding or subtracting the offset produced by moving the wrap point, all times between 1970 and 1999 from RTC hardware could get interpreted as times from 2070 to 2099, but the interpretation of dates between 2000 and 2069 would not change. Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: remove nvmem_configAlexandre Belloni2018-03-011-2/+0
| | | | | | | | | | Because nvmem_config is only used and copied at nvmem registration, remove it from struct rtc_device. All the rtc drivers using nvmem are now calling rtc_nvmem_register directly. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: nvmem: allow registering the nvmem device before the rtcAlexandre Belloni2018-03-011-2/+3
| | | | | | | | | | | | | | | | | | | | | | | Switch the parent of the nvmem device to the parent of the rtc device so it can be registered before the RTC. This is a small change in the ABI as the nvmem moves out of the /sys/class/rtc/rtcX folder to be under the parent device folder (that is where the previous nvram files where registered). However, it is still available under its correct location, /sys/bus/nvmem/devices which is the one that should be used by userspace applications. The other benefit is that the nvmem device can stay registered even if the rtc registration fails. Or it is possible to not register the rtc if the nvmem registration failed. Finally, it makes a lot of sense for devices that actually have different i2c or spi addresses for the RTC and the EEPROM. That is basically how it would end up when using MFD or even completely separate devices. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: nvmem: pass nvmem_config to rtc_nvmem_register()Alexandre Belloni2018-02-141-1/+1
| | | | | | | To be able to remove nvmem_config from struct rtc_device, pass it as a parameter to rtc_nvmem_register. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
* rtc: Allow rtc drivers to specify the tv_nsec value for ntpJason Gunthorpe2017-10-301-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ntp is currently hardwired to try and call the rtc set when wall clock tv_nsec is 0.5 seconds. This historical behaviour works well with certain PC RTCs, but is not universal to all rtc hardware. Change how this works by introducing the driver specific concept of set_offset_nsec, the delay between current wall clock time and the target time to set (with a 0 tv_nsecs). For x86-style CMOS set_offset_nsec should be -0.5 s which causes the last second to be written 0.5 s after it has started. For compat with the old rtc_set_ntp_time, the value is defaulted to + 0.5 s, which causes the next second to be written 0.5s before it starts, as things were before this patch. Testing shows many non-x86 RTCs would like set_offset_nsec ~= 0, so ultimately each RTC driver should set the set_offset_nsec according to its needs, and non x86 architectures should stop using update_persistent_clock64 in order to access this feature. Future patches will revise the drivers as needed. Since CMOS and RTC now have very different handling they are split into two dedicated code paths, sharing the support code, and ifdefs are replaced with IS_ENABLED. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Miroslav Lichvar <mlichvar@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Stephen Boyd <stephen.boyd@linaro.org> Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* rtc: add generic nvmem supportAlexandre Belloni2017-07-071-0/+4
| | | | | | | | | | | | Many RTCs have an on board non volatile storage. It can be battery backed RAM or an EEPROM. Use the nvmem subsystem to export it to both userspace and in-kernel consumers. This stays compatible with the previous (non documented) ABI that was using /sys/class/rtc/rtcx/device/nvram to export that memory. But will warn about the deprecation. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: introduce new registration methodAlexandre Belloni2017-07-071-0/+84
| | | | | | | | | | Introduce rtc_register_device() to register an already allocated and initialized struct rtc_device. It automatically sets up the owner and the two steps allocation/registration will allow to remove race conditions in the IRQ handling of some driver. It also allows to properly extend the core without adding more arguments to rtc_device_register(). Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: class separate id allocation from registrationAlexandre Belloni2017-07-071-19/+25
| | | | | | Create rtc_device_get_id to allocate the id for an RTC. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: class separate device allocation from registrationAlexandre Belloni2017-07-071-26/+37
| | | | | | | Create rtc_allocate_device to allocate memory for a struct rtc_device and initialize it. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: remove rtc_device.nameAlexandre Belloni2017-06-031-4/+3
| | | | | | | rtc->name is only used in messages were it is superfluous. Remove it completely from the structure. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: utilize new cdev_device_add helper functionLogan Gunthorpe2017-03-211-4/+10
| | | | | | | | | | | | | | | | | | | Mostly straightforward, but we had to remove the rtc_dev_add/del_device functions as they split up the cdev_add and the device_add. Doing this also revealed that there was likely another subtle bug: seeing cdev_add was done after device_register, the cdev probably was not ready before device_add when the uevent occurs. This would race with userspace, if it tried to use the device directly after the uevent. This is fixed just by using the new helper function. Another weird thing is this driver would, in some error cases, call cdev_add() without calling cdev_init. This patchset corrects this by avoiding calling cdev_add if the devt is not set. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* rtc: make class.c explicitly non-modularPaul Gortmaker2016-03-141-13/+0
| | | | | | | | | | | | | | | | | | | | | | | | The Makefile/Kconfig currently controlling compilation of this code is: obj-$(CONFIG_RTC_CLASS) += rtc-core.o rtc-core-y := class.o interface.o drivers/rtc/Kconfig:menuconfig RTC_CLASS drivers/rtc/Kconfig: bool "Real Time Clock" ...meaning that it currently is not being built as a module by anyone. Lets remove the modular code that is essentially orphaned, so that when reading the code there is no doubt it is builtin-only. We don't replace module.h with init.h since the file does need to know what a struct module is. We also delete the MODULE_LICENSE tag etc. since all that information is already contained at the top of the file in the comments. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: switch to using is_visible() to control sysfs attributesDmitry Torokhov2015-09-051-3/+1
| | | | | | | | | | | | Instead of creating wakealarm attribute manually, after the device has been registered, let's rely on facilities provided by the attribute groups to control which attributes are visible and which are not. This allows to create all needed attributes at once, at the same time that we register RTC class device. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: class: remove unnecessary device_get() in rtc_device_unregisterDmitry Torokhov2015-09-051-13/+12
| | | | | | | | | | | Technically the address of rtc->dev can never be NULL, so get_device() can never fail. Also caller of rtc_device_unregister() supposed to be the owner of the device and thus have a valid reference. Therefore call to get_device() is not needed here. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* rtc: class: fix double free in rtc_register_device() error pathDmitry Torokhov2015-09-051-4/+2
| | | | | | | | | | | | Commit 59cca865f21e ("drivers/rtc/class.c: fix device_register() error handling") correctly noted that naked kfree() should not be used after failed device_register() call, however, while it added the needed put_device() it forgot to remove the original kfree() causing double-free. Cc: Vasiliy Kulikov <segooon@gmail.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
* drivers/rtc/class.c: initialize rtc name earlyAaro Koskinen2015-04-171-3/+3
| | | | | | | | | | | | | | | | | In some error cases RTC name is used before it is initialized: rtc-rs5c372 0-0032: clock needs to be set rtc-rs5c372 0-0032: rs5c372b found, 24hr, driver version 0.6 rtc (null): read_time: fail to read rtc-rs5c372 0-0032: rtc core: registered rtc-rs5c372 as rtc0 Fix by initializing the name early. Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.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>
* time, drivers/rtc: Don't bother with rtc_resume() for the nonstop clocksourceXunlei Pang2015-04-031-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | If a system does not provide a persistent_clock(), the time will be updated on resume by rtc_resume(). With the addition of the non-stop clocksources for suspend timing, those systems set the time on resume in timekeeping_resume(), but may not provide a valid persistent_clock(). This results in the rtc_resume() logic thinking no one has set the time and it then will over-write the suspend time again, which is not necessary and only increases clock error. So, fix this for rtc_resume(). This patch also improves the name of persistent_clock_exist to make it more grammatical. Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1427945681-29972-19-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* drivers/rtc: Remove redundant rtc_valid_tm() from rtc_resume()Xunlei Pang2015-04-031-4/+0
| | | | | | | | | | | | rtc_read_time() has already judged valid tm by rtc_valid_tm(), so just remove it. Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1427945681-29972-17-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* rtc: Update suspend/resume timing to use 64bit timeJohn Stultz2014-11-211-15/+15
| | | | | | | | Currently the rtc suspend/resume timing is done using y2038 problematic timespecs. So update the code to utilize timespec64 types. Signed-off-by: John Stultz <john.stultz@linaro.org>
* driver/rtc/class.c: check the error after rtc_read_time()Hyogi Gim2014-08-091-2/+14
| | | | | | | | | | | | | | In rtc_suspend() and rtc_resume(), the error after rtc_read_time() is not checked. If rtc device fail to read time, we cannot guarantee the following process. Add the verification code for returned rtc_read_time() error. Signed-off-by: Hyogi Gim <hyogi.gim@lge.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc: honor device tree /alias entries when assigning IDsStephen Warren2014-01-241-4/+20
| | | | | | | | | | | | | | | | | | | | Assign RTC device IDs based on device tree /aliases entries if present, falling back to the existing numbering scheme if there is no /aliases entry (which includes when the system isn't booted using DT), or there is a numbering conflict. This is useful in systems with multiple RTC devices, to ensure that the best RTC device is selected as /dev/rtc0, which provides the overall system time. For example, Tegra has an on-SoC RTC that is not battery backed, typically coupled with an off-SoC RTC that is battery backed. Only the latter is useful for populating the system time, yet the former is useful e.g. for wakeup timing, since the time is not lost when the system is sleeps. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/rtc/class: convert from Legacy pm ops to dev_pm_opsShuah Khan2013-07-041-6/+6
| | | | | | | | | | | | | | | Convert drivers/rtc/class to use dev_pm_ops for power management and remove Legacy PM ops hooks. With this change, rtc class registers suspend/resume callbacks via class->pm (dev_pm_ops) instead of Legacy class->suspend/resume. When __device_suspend() runs call-backs, it will find class->pm ops for the rtc class. Signed-off-by: Shuah Khan <shuah.kh@samsung.com> Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Shuah Khan <shuahkhan@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>
* drivers/rtc/class.c: use struct device as the first argument for ↵Jingoo Han2013-04-301-3/+3
| | | | | | | | | | | | | | devm_rtc_device_register() Other devm_* APIs use 'struct device *dev' as the first argument. Thus, in order to sync with other devm_* functions, struct device is used as the first argument for devm_rtc_device_register(). Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Tejun Heo <tj@kernel.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>
* rtc: add devm_rtc_device_{register,unregister}()Jingoo Han2013-04-301-0/+70
| | | | | | | | | | These functions allow the driver core to automatically clean up any allocation made by rtc drivers. Thus it simplifies the error paths. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc: use dev_warn()/dev_dbg()/pr_err() instead of printk()Jingoo Han2013-02-221-1/+3
| | | | | | | | | | Fix the checkpatch warning as below: WARNING: Prefer netdev_err(netdev, ... then dev_err(dev, ... then pr_err(... to printk(KERN_ERR ... 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>
* Merge branch 'fortglx/3.9/time' of git://git.linaro.org/people/jstultz/linux ↵Thomas Gleixner2013-02-041-0/+7
|\ | | | | | | | | | | | | | | into timers/core Trivial conflict in arch/x86/Kconfig Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * rtc: Skip the suspend/resume handling if persistent clock existFeng Tang2013-01-161-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | All the RTC suspend and resume functions are to compensate the sleep time, but this is already done in timekeeping.c if persistent clock exist. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Arve Hjønnevåg <arve@android.com> Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | revert "rtc: recycle id when unloading a rtc driver"Andrew Morton2012-12-211-1/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | Revert commit 2830a6d20139df2198d63235df7957712adb28e5. We already perform the ida_simple_remove() in rtc_device_release(), which is an appropriate place. Commit 2830a6d20 ("rtc: recycle id when unloading a rtc driver") caused the kernel to emit ida_remove called for id=0 which is not allocated. warnings when rtc_device_release() tries to release an alread-released ID. Let's restore things to their previous state and then work out why Vincent's kernel wasn't calling rtc_device_release() - presumably a bug in a specific sub-driver. Reported-by: Lothar Waßmann <LW@KARO-electronics.de> Acked-by: Alexander Holler <holler@ahsoftware.de> Cc: Vincent Palatin <vpalatin@chromium.org> Cc: <stable@vger.kernel.org> [3.7.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc_sysfs_show_hctosys(): display 0 if resume failedDavid Fries2012-10-051-1/+7
| | | | | | | | | | | | | | | | | | | | | | | Without this patch /sys/class/rtc/$CONFIG_RTC_HCTOSYS_DEVICE/hctosys contains a 1 (meaning "This rtc was used to initialize the system clock") even if setting the time by do_settimeofday() at bootup failed. The RTC can also be used to set the clock on resume, if it did 1, otherwise 0. Previously there was no indication if the RTC was used to set the clock in resume. This uses only CONFIG_RTC_HCTOSYS_DEVICE for conditional compilation instead of it and CONFIG_RTC_HCTOSYS to be more consistent. rtc_hctosys_ret was moved to class.c so class.c no longer depends on hctosys.c. [sfr@canb.auug.org.au: fix build] Signed-off-by: David Fries <David@Fries.net> Cc: Matthew Garrett <mjg@redhat.com> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc: recycle id when unloading a rtc driverVincent Palatin2012-10-051-0/+1
| | | | | | | | | | | | | When calling rtc_device_unregister, we are not freeing the id used by the driver. So when doing a unload/load cycle for a RTC driver (e.g. rmmod rtc_cmos && modprobe rtc_cmos), its id is incremented by one. As a consequence, we no longer have neither an rtc0 driver nor a /proc/driver/rtc (as it only exists for the first driver). Signed-off-by: Vincent Palatin <vpalatin@chromium.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>
* Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2011-12-061-5/+5
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clockevents: Set noop handler in clockevents_exchange_device() tick-broadcast: Stop active broadcast device when replacing it clocksource: Fix bug with max_deferment margin calculation rtc: Fix some bugs that allowed accumulating time drift in suspend/resume rtc: Disable the alarm in the hardware
| * rtc: Fix some bugs that allowed accumulating time drift in suspend/resumeArve Hjønnevåg2011-11-231-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current code checks if abs(delta_delta.tv_sec) is greater or equal to two before it discards the old delta value, but this can trigger at close to -1 seconds since -1.000000001 seconds is stored as tv_sec -2 and tv_nsec 999999999 in a normalized timespec. rtc_resume had an early return check if the rtc value had not changed since rtc_suspend. This effectivly stops time for the duration of the short sleep. Check if sleep_time is positive after all the adjustments have been applied instead since this allows the old_system adjustment in rtc_suspend to have an effect even for short sleep cycles. CC: stable@kernel.org Signed-off-by: Arve Hjønnevåg <arve@android.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | drivers/rtc/class.c: convert idr to ida and use ida_simple_get()Jonathan Cameron2011-11-031-23/+9
|/ | | | | | | | | | This is the one use of an ida that doesn't retry on receiving -EAGAIN. I'm assuming do so will cause no harm and may help on a rare occasion. Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> 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>
* rtc: Avoid accumulating time drift in suspend/resumeJohn Stultz2011-06-221-17/+48
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* time: Add timekeeping_inject_sleeptimeJohn Stultz2011-04-261-14/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | Some platforms cannot implement read_persistent_clock, as their RTC devices are only accessible when interrupts are enabled. This keeps them from being used by the timekeeping code on resume to measure the time in suspend. The RTC layer tries to work around this, by calling do_settimeofday on resume after irqs are reenabled to set the time properly. However, this only corrects CLOCK_REALTIME, and does not properly adjust the sleep time value. This causes btime in /proc/stat to be incorrect as well as making the new CLOCK_BOTTTIME inaccurate. This patch resolves the issue by introducing a new timekeeping hook to allow the RTC layer to inject the sleep time on resume. The code also checks to make sure that read_persistent_clock is nonfunctional before setting the sleep time, so that should the RTC's HCTOSYS option be configured in on a system that does support read_persistent_clock we will not increase the total_sleep_time twice. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* RTC: Fix early irqs caused by calling rtc_set_alarm too earlyJohn Stultz2011-03-301-1/+1
| | | | | | | | | | | | | | | | | | | | | When we register an rtc device at boot, we read the alarm value in hardware and set the rtc device's aie_timer to that value. The initial method to do this was to simply call rtc_set_alarm() with the value read from hardware. However, this may cause problems as rtc_set_alarm may enable interupts, and the RTC alarm might fire, which can cause invalid pointer dereferencing since the RTC registration is not complete. This patch solves the issue by initializing the rtc_device.aie_timer y hand via rtc_initialize_alarm(). This avoids any calls to the RTC hardware which might enable interrupts too early. CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* RTC: Initialize kernel state from RTCJohn Stultz2011-03-091-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark Brown pointed out a corner case: that RTC alarms should be allowed to be persistent across reboots if the hardware supported it. The rework of the generic layer to virtualize the RTC alarm virtualized much of the alarm handling, and removed the code used to read the alarm time from the hardware. Mark noted if we want the alarm to be persistent across reboots, we need to re-read the alarm value into the virtualized generic layer at boot up, so that the generic layer properly exposes that value. This patch restores much of the earlier removed rtc_read_alarm code and wires it in so that we set the kernel's alarm value to what we find in the hardware at boot time. NOTE: Not all hardware supports persistent RTC alarm state across system reset. rtc-cmos for example will keep the alarm time, but disables the AIE mode irq. Applications should not expect the RTC alarm to be valid after a system reset. We will preserve what we can, to represent the hardware state at boot, but its not guarenteed. Further, in the future, with multiplexed RTC alarms, the soonest alarm to fire may not be the one set via the /dev/rt ioctls. So an application may set the alarm with RTC_ALM_SET, but after a reset find that RTC_ALM_READ returns an earlier time. Again, we preserve what we can, but applications should not expect the RTC alarm state to persist across a system reset. Big thanks to Mark for pointing out the issue! Thanks also to Marcelo for helping think through the solution. CC: Mark Brown <broonie@opensource.wolfsonmicro.com> CC: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> CC: rtc-linux@googlegroups.com Reported-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* RTC: Prevents a division by zero in kernel code.Marcelo Roberto Jimenez2011-02-031-0/+1
| | | | | | | | | | | | | | This patch prevents a user space program from calling the RTC_IRQP_SET ioctl with a negative value of frequency. Also, if this call is make with a zero value of frequency, there would be a division by zero in the kernel code. [jstultz: Also initialize irq_freq to 1 to catch other divbyzero issues] CC: Alessandro Zummo <a.zummo@towertech.it> CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br> Signed-off-by: John Stultz <john.stultz@linaro.org>
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