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>
Add a way for drivers to inform the core of the supported date/time range.
The core can then check whether the date/time or alarm is in the range
before calling ->set_time, ->set_mmss or ->set_alarm. It returns -ERANGE
when the time is out of range.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Since commit 34ce71a96d ("ALSA: timer: remove legacy rtctimer"), the
rtc_register/rtc_control/rtc_unregister API is unused. As it is highly
unlikely to be needed again, remove it.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
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>
Export rtc_nvmem_register() so it can be called from drivers instead of
only the core.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The last usage was removed in 5c82a6ae0 when rtc_device.name
was removed
Signed-off-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Pull timer updates from Thomas Gleixner:
"Yet another big pile of changes:
- More year 2038 work from Arnd slowly reaching the point where we
need to think about the syscalls themself.
- A new timer function which allows to conditionally (re)arm a timer
only when it's either not running or the new expiry time is sooner
than the armed expiry time. This allows to use a single timer for
multiple timeout requirements w/o caring about the first expiry
time at the call site.
- A new NMI safe accessor to clock real time for the printk timestamp
work. Can be used by tracing, perf as well if required.
- A large number of timer setup conversions from Kees which got
collected here because either maintainers requested so or they
simply got ignored. As Kees pointed out already there are a few
trivial merge conflicts and some redundant commits which was
unavoidable due to the size of this conversion effort.
- Avoid a redundant iteration in the timer wheel softirq processing.
- Provide a mechanism to treat RTC implementations depending on their
hardware properties, i.e. don't inflict the write at the 0.5
seconds boundary which originates from the PC CMOS RTC to all RTCs.
No functional change as drivers need to be updated separately.
- The usual small updates to core code clocksource drivers. Nothing
really exciting"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (111 commits)
timers: Add a function to start/reduce a timer
pstore: Use ktime_get_real_fast_ns() instead of __getnstimeofday()
timer: Prepare to change all DEFINE_TIMER() callbacks
netfilter: ipvs: Convert timers to use timer_setup()
scsi: qla2xxx: Convert timers to use timer_setup()
block/aoe: discover_timer: Convert timers to use timer_setup()
ide: Convert timers to use timer_setup()
drbd: Convert timers to use timer_setup()
mailbox: Convert timers to use timer_setup()
crypto: Convert timers to use timer_setup()
drivers/pcmcia: omap1: Fix error in automated timer conversion
ARM: footbridge: Fix typo in timer conversion
drivers/sgi-xp: Convert timers to use timer_setup()
drivers/pcmcia: Convert timers to use timer_setup()
drivers/memstick: Convert timers to use timer_setup()
drivers/macintosh: Convert timers to use timer_setup()
hwrng/xgene-rng: Convert timers to use timer_setup()
auxdisplay: Convert timers to use timer_setup()
sparc/led: Convert timers to use timer_setup()
mips: ip22/32: Convert timers to use timer_setup()
...
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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>
There are no driver left using .open and .release. There is no good use
case for them as there is nothing the character device interface does that
should not be done in the sysfs interface or in-kernel interface.
Remove those callbacks now to avoid future confusion.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
rtc_time_to_tm and rtc_tm_to_time are not deprecated and make perfect sense
for RTCs that are simple 32bit counters.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
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>
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->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>
A number of rtc devices, such as the NXP pcf2123 include a facility
to adjust the clock in order to compensate for temperature or a
crystal, capacitor, etc, that results in the rtc clock not running
at exactly 32.768 kHz.
Data sheets I have seen refer to this as a clock offset, and measure it
in parts per million, however they often reference ppm to 2 digits of
precision, which makes integer ppm less than ideal.
We use parts per billion, which more than covers the precision needed
and works nicely within 32 bits
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Now rtc_set_mmss() has no users, just remove it.
We still have rtc_set_time() doing similar things.
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
There're many sites need comparing the two rtc_time variants for many
rtc drivers, especially in the instances of rtc_class_ops::set_alarm().
So add this common helper function to make things easy.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
The rtc_timer_cancel() always returns 0 and cannot fail (calls only
other void-returning functions).
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Fix issues reported by checkpatch:
ERROR: open brace '{' following struct go on the same line
ERROR: "foo* bar" should be "foo *bar"
Additionally adjust alignment of wrapped function arguments.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Currently the rtc_class_op's set_mmss() function takes a 32-bit
second value (on 32-bit systems), which is problematic for dates
past y2038.
This patch provides a safe version named set_mmss64() using
y2038 safe time64_t.
After this patch, set_mmss() is deprecated and all its users
will be fixed to use set_mmss64(), it can be removed when having
no users.
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
[jstultz: Add whitespace fix for checkpatch]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1427945681-29972-8-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
rtc_set_ntp_time() uses timespec which is y2038-unsafe,
so modify to use timespec64 which is y2038-safe, then
replace rtc_time_to_tm() with rtc_time64_to_tm().
Also adjust all its call sites(only NTP uses it) accordingly.
Cc: pang.xunlei <pang.xunlei@linaro.org>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
As part of addressing "y2038 problem" for in-kernel uses, this patch
adds safe rtc_tm_to_time64()/rtc_time64_to_tm() respectively using
time64_t.
After this patch, rtc_tm_to_time() is deprecated and all its call
sites will be fixed using corresponding safe versions, it can be
removed when having no users. Also change rtc_tm_to_time64() to
return time64_t directly instead of just as a parameter like
rtc_tm_to_time() does.
After this patch, rtc_time_to_tm() is deprecated and all its call
sites will be fixed using corresponding safe versions, it can be
removed when having no users.
In addition, change rtc_tm_to_ktime() and rtc_ktime_to_tm() to use
the safe version in passing.
Signed-off-by: pang.xunlei <pang.xunlei@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
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>
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>
Here is the big driver core merge for 3.9-rc1
There are two major series here, both of which touch lots of drivers all
over the kernel, and will cause you some merge conflicts:
- add a new function called devm_ioremap_resource() to properly be
able to check return values.
- remove CONFIG_EXPERIMENTAL
If you need me to provide a merged tree to handle these resolutions,
please let me know.
Other than those patches, there's not much here, some minor fixes and
updates.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core patches from Greg Kroah-Hartman:
"Here is the big driver core merge for 3.9-rc1
There are two major series here, both of which touch lots of drivers
all over the kernel, and will cause you some merge conflicts:
- add a new function called devm_ioremap_resource() to properly be
able to check return values.
- remove CONFIG_EXPERIMENTAL
Other than those patches, there's not much here, some minor fixes and
updates"
Fix up trivial conflicts
* tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (221 commits)
base: memory: fix soft/hard_offline_page permissions
drivercore: Fix ordering between deferred_probe and exiting initcalls
backlight: fix class_find_device() arguments
TTY: mark tty_get_device call with the proper const values
driver-core: constify data for class_find_device()
firmware: Ignore abort check when no user-helper is used
firmware: Reduce ifdef CONFIG_FW_LOADER_USER_HELPER
firmware: Make user-mode helper optional
firmware: Refactoring for splitting user-mode helper code
Driver core: treat unregistered bus_types as having no devices
watchdog: Convert to devm_ioremap_resource()
thermal: Convert to devm_ioremap_resource()
spi: Convert to devm_ioremap_resource()
power: Convert to devm_ioremap_resource()
mtd: Convert to devm_ioremap_resource()
mmc: Convert to devm_ioremap_resource()
mfd: Convert to devm_ioremap_resource()
media: Convert to devm_ioremap_resource()
iommu: Convert to devm_ioremap_resource()
drm: Convert to devm_ioremap_resource()
...
All in-kernel users of class_find_device() don't really need mutable
data for match callback.
In two places (kernel/power/suspend_test.c, drivers/scsi/osd/osd_uld.c)
this patch changes match callbacks to use const search data.
The const is propagated to rtc_class_open() and power_supply_get_by_name()
parameters.
Note that there's a dev reference leak in suspend_test.c that's not
touched in this patch.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The purpose of this option is to allow ARM/etc systems that rely on the
class RTC subsystem to have the same kind of automatic NTP based
synchronization that we have on PC platforms. Today ARM does not
implement update_persistent_clock and makes extensive use of the class
RTC system.
When enabled CONFIG_RTC_SYSTOHC will provide a generic
rtc_update_persistent_clock that stores the current time in the RTC and
is intended complement the existing CONFIG_RTC_HCTOSYS option that loads
the RTC at boot.
Like with RTC_HCTOSYS the platform's update_persistent_clock is used
first, if it works. Platforms with mixed class RTC and non-RTC drivers
need to return ENODEV when class RTC should be used. Such an update for
PPC is included in this patch.
Long term, implementations of update_persistent_clock should migrate to
proper class RTC drivers and use CONFIG_RTC_SYSTOHC instead.
Tested on ARM kirkwood and PPC405
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
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>
Currently there is no generic way to get the RTC battery status within an
application. So add an ioctl to read the status bit. The idea is that
the bit is set once a low voltage is detected. It stays there until it is
reset using the RTC_VL_CLR ioctl.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.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>
Richard Weinberger noticed that on some RTC hardware that
doesn't support UIE mode, due to coarse granular alarms
(like 1minute resolution), the current virtualized RTC
support doesn't properly error out when UIE is enabled.
Instead the current code queues an alarm for the next second,
but it won't fire until up to a miniute later.
This patch provides a generic way to flag this sort of hardware
and fixes the issue on the mpc5121 where Richard noticed the
problem.
CC: stable@vger.kernel.org
Reported-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: John Stultz <john.stultz@linaro.org>
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>
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>
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.
This patch removes the driver hooks and implementations of
update_irq_enable if no one else is calling it.
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
CC: rtc-linux@googlegroups.com
Signed-off-by: John Stultz <john.stultz@linaro.org>
With the generic rtc code now emulating PIE mode irqs via an
hrtimer, no one calls the rtc_class_ops->irq_set_freq call.
This patch removes the hook and deletes the driver functions
if no one else calls them.
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
CC: rtc-linux@googlegroups.com
Signed-off-by: John Stultz <john.stultz@linaro.org>
With PIE mode interrupts now emulated in generic code via an hrtimer,
no one calls rtc_class_ops->irq_set_state(), so this patch removes it
along with driver implementations.
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
CC: rtc-linux@googlegroups.com
Signed-off-by: John Stultz <john.stultz@linaro.org>
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>
This patch re-enables UIE timer/polling emulation for rtc devices
that do not support alarm irqs.
CC: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
CC: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Uwe pointed out that my alarm based UIE emulation is not sufficient
to replace the older timer/polling based UIE emulation on devices
where there is no alarm irq. This causes rtc devices without alarms
to return -EINVAL to UIE ioctls. The fix is to re-instate the old
timer/polling method for devices without alarm irqs.
This patch reverts the following commits:
042620a018 - Remove UIE emulation
1daeddd596 - Cleanup removed UIE emulation declaration
b5cc8ca1c9 - Remove Kconfig symbol for UIE emulation
The emulation mode will still need to be wired-in with a following
patch before it will work.
CC: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
CC: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
In cases where RTC hardware does not support alarms, the virtualized
RTC interfaces did not have a way to propagate the error up to userland.
This patch extends rtc_timer_enqueue so it catches errors from the hardware
and returns them upwards to the virtualized interfaces. To simplify error
handling, it also internalizes the management of the timer->enabled bit
into rtc_timer_enqueue and rtc_timer_remove.
Also makes rtc_timer_enqueue and rtc_timer_remove static.
Reported-by: David Daney <ddaney@caviumnetworks.com>
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diagnosed-by: David Daney <ddaney@caviumnetworks.com>
Tested-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML-Reference: <1295565973-14358-1-git-send-email-john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
rtc_dev_update_irq_enable_emul was removed in commit
042620a018 (UIE emulation is
now handled via hrtimer), but the declaration was missed.
This patch cleans it up.
Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML-Reference: <1294939849-20608-1-git-send-email-john.stultz@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
rtctimer_* is already occupied by sound/core/rtctimer.c. Instead of
fiddling with that, rename the new functions to rtc_timer_* which
reads nicer anyway.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <johnstul@us.ibm.com>
Since we provide UIE interrupts via a rtc_timer, the old
emulation code can be removed.
Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML Reference: <1290136329-18291-5-git-send-email-john.stultz@linaro.org>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Richard Cochran <richardcochran@gmail.com>
This patch reworks a large portion of the generic RTC code
to in-effect virtualize the rtc interrupt code.
The current RTC interface is very much a raw hardware interface.
Via the proc, /dev/, or sysfs interfaces, applciations can set
the hardware to trigger interrupts in one of three modes:
AIE: Alarm interrupt
UIE: Update interrupt (ie: once per second)
PIE: Periodic interrupt (sub-second irqs)
The problem with this interface is that it limits the RTC hardware
so it can only be used by one application at a time.
The purpose of this patch is to extend the RTC code so that we can
multiplex multiple applications event needs onto a single RTC device.
This is done by utilizing the timerqueue infrastructure to manage
a list of events, which cause the RTC hardware to be programmed
to fire an interrupt for the next event in the list.
In order to preserve the functionality of the exsting proc,/dev/ and
sysfs interfaces, we emulate the different interrupt modes as follows:
AIE: We create a rtc_timer dedicated to AIE mode interrupts. There is
only one per device, so we don't change existing interface semantics.
UIE: Again, a dedicated rtc_timer, set for periodic mode, is used
to emulate UIE interrupts. Again, only one per device.
PIE: Since PIE mode interrupts fire faster then the RTC's clock read
granularity, we emulate PIE mode interrupts using a hrtimer. Again,
one per device.
With this patch, the rtctest.c application in Documentation/rtc.txt
passes fine on x86 hardware. However, there may very well still be
bugs, so greatly I'd appreciate any feedback or testing!
Signed-off-by: John Stultz <john.stultz@linaro.org>
LKML Reference: <1290136329-18291-4-git-send-email-john.stultz@linaro.org>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Richard Cochran <richardcochran@gmail.com>
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 reading the time at bootup failed.
Moreover change error handling in rtc_hctosys() to use goto and so reduce
the indention level.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Paul Gortmaker <p_gortmaker@yahoo.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- the LEAP_YEAR macro is buggy - it references its arg multiple times.
Fix this by turning it into a C function.
- give it a more approriate name
- Move it to rtc.h so that other .c files can use it, instead of copying it.
Cc: dann frazier <dannf@hp.com>
Acked-by: Alessandro Zummo <alessandro.zummo@towertech.it>
Cc: stephane eranian <eranian@googlemail.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add standard interfaces for alarm/update irqs enabling. Drivers are no
more required to implement equivalent ioctl code as rtc-dev will provide
it.
UIE emulation should now be handled correctly and will work even for those
RTC drivers who cannot be configured to do both UIE and AIE.
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
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>
The following functions can now become static:
- rtc_interrupt()
- rtc_get_rtc_time()
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Bernhard Walle <bwalle@suse.de>
Acked-by: Paul Gortmaker <p_gortmaker@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexandre Belloni