Commit Graph

111 Commits

Author SHA1 Message Date
Alexandre Belloni
348c11a7d7 rtc: stop warning for invalid alarms when the alarm is disabled
When the alarm is not enabled, it may never have been set and so we can't
expect it to be valid. This will prevent the apparition of boot messages
like this one:

rtc rtc0: invalid alarm value: 2023-7-8 45:85:85

Link: https://lore.kernel.org/r/20230827221532.543353-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2023-09-06 01:25:15 +02:00
Alexandre Belloni
a783c96261 rtc: allow rtc_read_alarm without read_alarm callback
.read_alarm is not necessary to read the current alarm because it is
recorded in the aie_timer and so rtc_read_alarm() will never call
rtc_read_alarm_internal() which is the only function calling the callback.

Reported-by: Zhipeng Wang <zhipeng.wang_1@nxp.com>
Reported-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Fixes: 7ae41220ef ("rtc: introduce features bitfield")
Tested-by: Philippe Schenker <philippe.schenker@toradex.com>
Link: https://lore.kernel.org/r/20230214222754.582582-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2023-02-22 12:32:05 +01:00
shaomin Deng
b9354487fb rtc: remove duplicated words in comments
Signed-off-by: shaomin Deng <dengshaomin@cdjrlc.com>
Link: https://lore.kernel.org/r/20220808152354.3641-1-dengshaomin@cdjrlc.com
Link: https://lore.kernel.org/r/20220808153454.6844-1-dengshaomin@cdjrlc.com
Link: https://lore.kernel.org/r/20220808152822.5012-1-dengshaomin@cdjrlc.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2022-12-15 23:34:31 +01:00
Tom Rix
915593a7a6 rtc: check if __rtc_read_time was successful
Clang static analysis reports this issue
interface.c:810:8: warning: Passed-by-value struct
  argument contains uninitialized data
  now = rtc_tm_to_ktime(tm);
      ^~~~~~~~~~~~~~~~~~~

tm is set by a successful call to __rtc_read_time()
but its return status is not checked.  Check if
it was successful before setting the enabled flag.
Move the decl of err to function scope.

Fixes: 2b2f5ff00f ("rtc: interface: ignore expired timers when enqueuing new timers")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20220326194236.2916310-1-trix@redhat.com
2022-03-29 22:45:50 +02:00
Alexandre Belloni
d87f741ddd rtc: handle alarms with a minute resolution
Handle alarms with a minute resolution in the core. Until now drivers have
been open coding the seconds part removal and have been doing that wrongly.
Most of them are rounding up which means the allow the system to miss
deadlines. So, round down and let __rtc_set_alarm return immediately if the
time has already passed.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211107225458.111068-1-alexandre.belloni@bootlin.com
2021-11-10 00:45:56 +01:00
Alexandre Belloni
adb17a053e rtc: expose RTC_FEATURE_UPDATE_INTERRUPT
Set RTC_FEATURE_UPDATE_INTERRUPT by default and clear it when it is not
supported.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211018152337.78732-1-alexandre.belloni@bootlin.com
2021-10-18 17:25:52 +02:00
Alexandre Belloni
c55c3a516c rtc: rtc_update_irq_enable: rework UIE emulation
Now that the core is aware of whether alarms are available, it is possible
to decide whether UIE emulation is required before actually trying to set
the alarm.

This greatly simplifies rtc_update_irq_enable because there is now only one
error value to track and is not relying on the return value of
__rtc_set_alarm anymore.

Tested-by: Łukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210418000023.995758-3-alexandre.belloni@bootlin.com
2021-04-29 23:04:13 +02:00
Alexandre Belloni
7ae41220ef rtc: introduce features bitfield
Introduce a bitfield to allow the drivers to announce the available
features for an RTC.

The main use case would be to better handle alarms, that could be present
or not or have a minute resolution or may need a correct week day to be set.

Use the newly introduced RTC_FEATURE_ALARM bit to then test whether alarms
are available instead of relying on the presence of ops->set_alarm.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210110231752.1418816-2-alexandre.belloni@bootlin.com
2021-01-16 23:19:26 +01:00
Alexandre Belloni
55dcf7a21d rtc: interface: fix kerneldoc comments
Fix kerneldoc warnings:

drivers/rtc/interface.c:619: warning: Function parameter or member 'num' not described in 'rtc_handle_legacy_irq'
drivers/rtc/interface.c:619: warning: Function parameter or member 'mode' not described in 'rtc_handle_legacy_irq'
drivers/rtc/interface.c:804: warning: Function parameter or member 'rtc' not described in 'rtc_timer_enqueue'
drivers/rtc/interface.c:804: warning: Function parameter or member 'timer' not described in 'rtc_timer_enqueue'
drivers/rtc/interface.c:864: warning: Function parameter or member 'rtc' not described in 'rtc_timer_remove'
drivers/rtc/interface.c:864: warning: Function parameter or member 'timer' not described in 'rtc_timer_remove'
drivers/rtc/interface.c:900: warning: Function parameter or member 'work' not described in 'rtc_timer_do_work'
drivers/rtc/interface.c:1035: warning: Function parameter or member 'rtc' not described in 'rtc_read_offset'
drivers/rtc/interface.c:1035: warning: Function parameter or member 'offset' not described in 'rtc_read_offset'
drivers/rtc/interface.c:1070: warning: Function parameter or member 'rtc' not described in 'rtc_set_offset'
drivers/rtc/interface.c:1070: warning: Function parameter or member 'offset' not described in 'rtc_set_offset'

Link: https://lore.kernel.org/r/20191127082932.666869-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-11-27 09:31:08 +01:00
Alexandre Belloni
3e74ddaa7c rtc: disallow update interrupts when time is invalid
Never enable update interrupts when the time set on the rtc is invalid.
In that case, also avoid enabling the emulation because it will fail for
the same reason.

Link: https://lore.kernel.org/r/20191021155631.3342-2-alexandre.belloni@bootlin.com
Link: https://lore.kernel.org/r/CA+ASDXMarBG5C1Kz42B9i_iVZ1=i6GgH9Yja2cdmSueKD_As_g@mail.gmail.com
Reported-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Reported-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-11-08 16:14:09 +01:00
Alexandre Belloni
7e7c005b4b rtc: disable uie before setting time and enable after
When setting the time in the future with the uie timer enabled,
rtc_timer_do_work will loop for a while because the expiration of the uie
timer was way before the current RTC time and a new timer will be enqueued
until the current rtc time is reached.

If the uie timer is enabled, disable it before setting the time and enable
it after expiring current timers (which may actually be an alarm).

This is the safest thing to do to ensure the uie timer is still
synchronized with the RTC, especially in the UIE emulation case.

Reported-by: syzbot+08116743f8ad6f9a6de7@syzkaller.appspotmail.com
Fixes: 6610e0893b ("RTC: Rework RTC code to use timerqueue for events")
Link: https://lore.kernel.org/r/20191020231320.8191-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-11-08 16:14:09 +01:00
Emmanuel Nicolet
eaa6ef563d rtc: interface: use timeu64_t for range_max
For rtc drivers where rtc->range_max is set U64_MAX, like the PS3 rtc,
rtc_valid_range() always returns -ERANGE. This is because the local
variable range_max has type time64_t, so the test
	if (time < range_min || time > range_max)
		return -ERANGE;
becomes (time < range_min || time > -1), which always evaluates to true.
timeu64_t should be used, since it's the type of rtc->range_max.

Signed-off-by: Emmanuel Nicolet <emmanuel.nicolet@gmail.com>
Link: https://lore.kernel.org/r/20190927110446.GA6289@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-10-03 21:55:17 +02:00
Suzuki K Poulose
6cda08a20d drivers: Introduce device lookup variants by name
Add a helper to match the device name for device lookup. Also
reuse this generic exported helper for the existing bus_find_device_by_name().
and add similar variants for driver/class.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Murphy <dmurphy@ti.com>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: linux-leds@vger.kernel.org
Cc: linux-rtc@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: linux-wpan@vger.kernel.org
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Stefan Schmidt <stefan@datenfreihafen.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20190723221838.12024-2-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-30 13:07:41 +02:00
Puranjay Mohan
3126790d1f rtc: interface: Change type of 'count' from int to u64
Callers of hrtimer_forward_now() should save the return value in u64.
function rtc_pie_update_irq() stores it in variable 'count' of type int
change type of count from unsigned long to u64 to solve the issue.

Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
Link: https://lore.kernel.org/r/20190618042351.9692-1-puranjay12@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-07-13 13:53:22 +02:00
Alexandre Belloni
a01ab0669d rtc: drop set_mms and set_mmss64
There are no users of set_mms and set_mmss64 as they have all been
converted to set_time and are handling the tm to time conversion on their
own.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-05-08 22:14:36 +02:00
Wolfram Sang
c48cadf5bf rtc: don't reference bogus function pointer in kdoc
The mentioned function pointer is long gone since early 2011. Remove the
reference in the comment and reword it slightly.

Fixes: 51ba60c5bb ("RTC: Cleanup rtc_class_ops->update_irq_enable()")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-04-04 10:07:11 +02:00
Alexandre Belloni
606cc43c72 rtc: core: correct trivial checkpatch warnings
Correct trivial checkpatch warnings, mostly whitespace issues and
unbalanced braces.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-04-04 10:07:08 +02:00
Alexandre Belloni
cdf7545aef rtc: convert core to SPDX identifier
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>
2019-03-18 03:36:01 +01:00
Alexandre Belloni
9a03201170 rtc: enforce rtc_timer_init private_data type
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>
2018-12-18 22:53:29 +01:00
Andy Shevchenko
5548cbf7f1 rtc: Switch to use %ptR
Use %ptR instead of open coded variant to print content of
struct rtc_time in human readable format.

Note, we drop the validation option. This is only used in
a deprecated ABI and is mostly wrong as many RTCs will still be valid
after 2100.

Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-12-10 22:39:37 +01:00
Alexandre Belloni
f1c8bc332e rtc: remove irq_task from kerneldoc
Stale mentions of irq_task are left in the kerneldoc after its removal.
Remove them.

There is still one indirect mention left but commit 3c8bb90efb ("rtc: Fix
hrtimer deadlock") can probably be reverted now.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-09-13 15:43:07 +02:00
Linus Torvalds
bfebeb1672 RTC for 4.19
Subsystem:
  - new helpers to add custom sysfs attributes
  - struct rtc_task removal along with rtc_irq_register/rtc_irq_unregister
  - rtc_irq_set_state and rtc_irq_set_freq are not exported anymore
 
 Drivers:
  - armada38x: reset after rtc power loss
  - ds1307: now supports m41t11
  - isl1208: now supports isl1219 and tamper detection
  - pcf2127: internal SRAM support
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Merge tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "It is now possible to add custom sysfs attributes while avoiding a
  possible race condition. Unused code has been removed resulting in a
  nice reduction of the code base. And more drivers have been switched
  to SPDX by their maintainers.

 Summary:

  Subsystem:
   - new helpers to add custom sysfs attributes
   - struct rtc_task removal along with rtc_irq_[un]register()
   - rtc_irq_set_state and rtc_irq_set_freq are not exported anymore

  Drivers:
   - armada38x: reset after rtc power loss
   - ds1307: now supports m41t11
   - isl1208: now supports isl1219 and tamper detection
   - pcf2127: internal SRAM support"

* tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (34 commits)
  rtc: ds1307: simplify hwmon config
  rtc: s5m: Add SPDX license identifier
  rtc: maxim: Add SPDX license identifiers
  rtc: isl1219: add device tree documentation
  rtc: isl1208: set ev-evienb bit from device tree
  rtc: isl1208: Add "evdet" interrupt source for isl1219
  rtc: isl1208: add support for isl1219 with tamper detection
  rtc: sysfs: facilitate attribute add to rtc device
  rtc: remove struct rtc_task
  char: rtc: remove task handling
  rtc: pcf85063: preserve control register value between stop and start
  rtc: sh: remove unused variable rtc_dev
  rtc: unexport rtc_irq_set_*
  rtc: simplify rtc_irq_set_state/rtc_irq_set_freq
  rtc: remove irq_task and irq_task_lock
  rtc: remove rtc_irq_register/rtc_irq_unregister
  rtc: sh: remove dead code
  rtc: sa1100: don't set PIE frequency
  rtc: ds1307: support m41t11 variant
  rtc: ds1307: fix data pointer to m41t0
  ...
2018-08-20 16:30:27 -07:00
Alexandre Belloni
5a5ba10f44 rtc: remove struct rtc_task
Include rtc_task members directly in rtc_timer member.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-08-02 17:16:05 +02:00
Alexandre Belloni
c842697c74 rtc: unexport rtc_irq_set_*
Make the rtc_irq_set interface internale to the RTC subsystem.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-07-26 15:08:53 +02:00
Alexandre Belloni
8719d3c918 rtc: simplify rtc_irq_set_state/rtc_irq_set_freq
The PIE doesn't handle tasks anymore, remove the pointer from the
interface.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-07-26 15:08:53 +02:00
Alexandre Belloni
acecb3ad8b rtc: remove irq_task and irq_task_lock
There is no way to set a periodic task anymore, remove task pointer and
lock.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-07-26 15:08:53 +02:00
Alexandre Belloni
1560d0848a rtc: remove rtc_irq_register/rtc_irq_unregister
The rtc_irq_* interface is not used from outside the RTC subsytem since
2016.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-07-26 15:08:50 +02:00
Alexandre Belloni
fd6792bb02 rtc: fix alarm read and set offset
The offset needs to be added after reading the alarm value.

It also needs to be subtracted after the now < alarm test.

Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-07-13 10:37:54 +02:00
Alexandre Belloni
abfdff44bc rtc: ensure rtc_set_alarm fails when alarms are not supported
When using RTC_ALM_SET or RTC_WKALM_SET with rtc_wkalrm.enabled not set,
rtc_timer_enqueue() is not called and rtc_set_alarm() may succeed but the
subsequent RTC_AIE_ON ioctl will fail. RTC_ALM_READ would also fail in that
case.

Ensure rtc_set_alarm() fails when alarms are not supported to avoid letting
programs think the alarms are working for a particular RTC when they are
not.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-06-07 20:09:49 +02:00
Baolin Wang
989515647e rtc: Add one offset seconds to expand RTC range
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>
2018-03-17 14:20:55 +01:00
Baolin Wang
4c4e5df1f3 rtc: Factor out the RTC range validation into rtc_valid_range()
The RTC range validation code can be factored into rtc_valid_range()
function to avoid duplicate code.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-03-17 14:20:54 +01:00
Alexandre Belloni
71db049e73 rtc: Add RTC range
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>
2018-03-17 14:20:54 +01:00
Baolin Wang
29a1f599c0 rtc: Add tracepoints for RTC system
It will be more helpful to add some tracepoints to track RTC actions when
debugging RTC driver. Below sample is that we set/read the RTC time, then
set 2 alarms, so we can see the trace logs:

set/read RTC time:
kworker/0:1-67 [000] 21.814245: rtc_set_time: UTC (1510301580) (0)
kworker/0:1-67 [000] 21.814312: rtc_read_time: UTC (1510301580) (0)

set the first alarm timer:
kworker/0:1-67 [000] 21.829238: rtc_timer_enqueue: RTC timer:(ffffffc15eb49bc8) expires:1510301700000000000 period:0
kworker/0:1-67 [000] 22.018279: rtc_set_alarm: UTC (1510301700) (0)

set the second alarm timer:
kworker/0:1-67 [000] 22.230284: rtc_timer_enqueue: RTC timer:(ffffff80088e6430) expires:1510301820000000000 period:0

the first alarm timer was expired:
kworker/0:1-67 [000] 145.155584: rtc_timer_dequeue: RTC timer:(ffffffc15eb49bc8) expires:1510301700000000000 period:0
kworker/0:1-67 [000] 145.155593: rtc_timer_fired: RTC timer:(ffffffc15eb49bc8) expires:1510301700000000000 period:0
kworker/0:1-67 [000] 145.172504: rtc_set_alarm: UTC (1510301820) (0)

the second alarm timer was expired:
kworker/0:1-67 [000] 269.102353: rtc_timer_dequeue: RTC timer:(ffffff80088e6430) expires:1510301820000000000 period:0
kworker/0:1-67 [000] 269.102360: rtc_timer_fired: RTC timer:(ffffff80088e6430) expires:1510301820000000000 period:0

disable alarm irq:
kworker/0:1-67 [000] 269.102469: rtc_alarm_irq_enable: disable RTC alarm IRQ (0)

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2018-02-13 21:30:22 +01:00
Russell King
8a25c8f66c rtc: clarify the RTC offset correction
The RTC offset correction documentation is not very clear about the
exact relationship between "offset" and the effect it has on the RTC.
Supplement the documentation with an equation giving the relationship.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-10-25 23:05:52 +02:00
Alexandre Belloni
74717b28cb rtc: set the alarm to the next expiring timer
If there is any non expired timer in the queue, the RTC alarm is never set.
This is an issue when adding a timer that expires before the next non
expired timer.

Ensure the RTC alarm is set in that case.

Fixes: 2b2f5ff00f ("rtc: interface: ignore expired timers when enqueuing new timers")
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-09-28 13:53:27 +02:00
Vaibhav Jain
da96aea0ed rtc: interface: Validate alarm-time before handling rollover
In function __rtc_read_alarm() its possible for an alarm time-stamp to
be invalid even after replacing missing components with current
time-stamp. The condition 'alarm->time.tm_year < 70' will trigger this
case and will cause the call to 'rtc_tm_to_time64(&alarm->time)'
return a negative value for variable t_alm.

While handling alarm rollover this negative t_alm (assumed to seconds
offset from '1970-01-01 00:00:00') is converted back to rtc_time via
rtc_time64_to_tm() which results in this error log with seemingly
garbage values:

"rtc rtc0: invalid alarm value: -2-1--1041528741
2005511117:71582844:32"

This error was generated when the rtc driver (rtc-opal in this case)
returned an alarm time-stamp of '00-00-00 00:00:00' to indicate that
the alarm is disabled. Though I have submitted a separate fix for the
rtc-opal driver, this issue may potentially impact other
existing/future rtc drivers.

To fix this issue the patch validates the alarm time-stamp just after
filling up the missing datetime components and if rtc_valid_tm() still
reports it to be invalid then bails out of the function without
handling the rollover.

Reported-by: Steve Best <sbest@redhat.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-05-31 13:04:54 +02:00
Thomas Gleixner
8b0e195314 ktime: Cleanup ktime_set() usage
ktime_set(S,N) was required for the timespec storage type and is still
useful for situations where a Seconds and Nanoseconds part of a time value
needs to be converted. For anything where the Seconds argument is 0, this
is pointless and can be replaced with a simple assignment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Thomas Gleixner
2456e85535 ktime: Get rid of the union
ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.

Get rid of the union and just keep ktime_t as simple typedef of type s64.

The conversion was done with coccinelle and some manual mopping up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Uwe Kleine-König
6785b3b60b rtc: fix a typo and reduce three empty lines to one
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-07-11 23:22:35 +02:00
Colin Ian King
2b2f5ff00f rtc: interface: ignore expired timers when enqueuing new timers
This patch fixes a RTC wakealarm issue, namely, the event fires during
hibernate and is not cleared from the list, causing hwclock to block.

The current enqueuing does not trigger an alarm if any expired timers
already exist on the timerqueue. This can occur when a RTC wake alarm
is used to wake a machine out of hibernate and the resumed state has
old expired timers that have not been removed from the timer queue.
This fix skips over any expired timers and triggers an alarm if there
are no pending timers on the timerqueue. Note that the skipped expired
timer will get reaped later on, so there is no need to clean it up
immediately.

The issue can be reproduced by putting a machine into hibernate and
waking it with the RTC wakealarm.  Running the example RTC test program
from tools/testing/selftests/timers/rtctest.c after the hibernate will
block indefinitely.  With the fix, it no longer blocks after the
hibernate resume.

BugLink: http://bugs.launchpad.net/bugs/1333569

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-06-04 15:43:22 +02:00
Uwe Kleine-König
d68778b80d rtc: initialize output parameter for read alarm to "uninitialized"
rtc drivers are supposed to set values they don't support to -1. To
simplify this for drivers and also make it harder for them to get it
wrong initialize the values to -1.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2016-05-30 01:37:11 +02:00
Joshua Clayton
b3967067c2 rtc: Add functions to set and read rtc offset
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>
2016-03-14 17:08:15 +01:00
viresh kumar
e7cba884af rtc: Drop (un)likely before IS_ERR(_OR_NULL)
IS_ERR(_OR_NULL) already contain an 'unlikely' compiler flag and there
is no need to do that again from its callers. Drop it.

gemini driver was using likely() for a failure case while the rtc driver
is getting registered. That looks wrong and it should really be
unlikely. But because we are killing all the unlikely() flags, lets kill
that too.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2015-09-05 13:19:09 +02:00
Xunlei Pang
c86a6c2895 rtc: interface: Remove rtc_set_mmss()
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>
2015-06-25 01:13:43 +02:00
Krzysztof Kozlowski
73744a64aa rtc: interface: Remove unused return value from rtc_timer_cancel()
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>
2015-06-19 20:03:20 +02:00
Aaro Koskinen
d0bddb512d drivers/rtc/interface.c: __rtc_read_time: reduce log level
__rtc_read_time logs should be debug logs instead of error logs.

For example, when the RTC clock is not set, it's not really useful
to print a kernel error log every time someone tries to read the clock:

	~ # hwclock -r
	[  604.508263] rtc rtc0: read_time: fail to read
	hwclock: RTC_RD_TIME: Invalid argument

If there's a real error, it's likely that lower level or higher level
code will tell it anyway. Make these logs debug logs, and also print
the error code for the read failure.

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>
2015-04-17 09:04:01 -04:00
Xunlei Pang
8e4ff1a81a drivers/rtc: Provide y2038 safe rtc_class_ops.set_mmss() replacement
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>
2015-04-03 08:18:24 +02:00
Xunlei Pang
bc10aa93a8 rtc: Update interface.c to use y2038-safe time interfaces
Currently, interface.c uses y2038 problematic rtc_tm_to_time()
and rtc_time_to_tm(). So replace them with their corresponding
y2038-safe versions: rtc_tm_to_time64() and rtc_time64_to_tm().

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>
2015-01-23 17:21:55 -08:00
Xunlei Pang
6528b88995 rtc: refine rtc_timer_do_work() to consider other set alarm failures
rtc_timer_do_work() only judges -ETIME failure of__rtc_set_alarm(), but
doesn't handle other failures like -EIO, -EBUSY, etc.

If there is a failure other than -ETIME, the next rtc_timer will stay in
the timerqueue.  Then later rtc_timers will be enqueued directly because
they have a later expires time, so the alarm irq will never be programmed.

When such failures happen, this patch will retry __rtc_set_alarm(), if
still can't program the alarm time, it will remove current rtc_timer from
timerqueue and fetch next one, thus preventing it from affecting other rtc
timers.

Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Arnd Bergmann <arnd.bergmann@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-10 17:41:16 -08:00
Hyogi Gim
16682c86d2 drivers/rtc/interface.c: check the validation of rtc_time in __rtc_read_time
Some rtc devices always return '0' when rtc_class_ops.read_time is
called.  So if rtc_time isn't verified in callback, rtc interface cannot
know whether rtc_time is valid.

Check rtc_time by using 'rtc_valid_tm' in '__rtc_read_time'.  And add
the message for debugging.

Signed-off-by: Hyogi Gim <hyogi.gim@lge.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
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>
2014-12-10 17:41:13 -08:00