user/sven/linux.git/drivers/rtc/interface.c, branch v4.19.170

rtc: disable uie before setting time and enable after

2019-12-17T19:35:43Z

commit 7e7c005b4b1f1f169bcc4b2c3a40085ecc663df2 upstream. 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: 6610e0893b8b ("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 Signed-off-by: Greg Kroah-Hartman

Merge tag 'rtc-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

2018-08-20T23:30:27Z

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 ...

rtc: remove struct rtc_task

2018-08-02T15:16:05Z

Include rtc_task members directly in rtc_timer member. Signed-off-by: Alexandre Belloni

rtc: unexport rtc_irq_set_*

2018-07-26T13:08:53Z

Make the rtc_irq_set interface internale to the RTC subsystem. Signed-off-by: Alexandre Belloni

rtc: simplify rtc_irq_set_state/rtc_irq_set_freq

2018-07-26T13:08:53Z

The PIE doesn't handle tasks anymore, remove the pointer from the interface. Signed-off-by: Alexandre Belloni

rtc: remove irq_task and irq_task_lock

2018-07-26T13:08:53Z

There is no way to set a periodic task anymore, remove task pointer and lock. Signed-off-by: Alexandre Belloni

rtc: remove rtc_irq_register/rtc_irq_unregister

2018-07-26T13:08:50Z

The rtc_irq_* interface is not used from outside the RTC subsytem since 2016. Signed-off-by: Alexandre Belloni

rtc: fix alarm read and set offset

2018-07-13T08:37:54Z

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 Signed-off-by: Alexandre Belloni

rtc: ensure rtc_set_alarm fails when alarms are not supported

2018-06-07T18:09:49Z

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

rtc: Add one offset seconds to expand RTC range

2018-03-17T13:20:55Z

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 Signed-off-by: Alexandre Belloni