Commit Graph

91 Commits

Author SHA1 Message Date
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 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