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 <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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>

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>

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>

The mentioned function pointer is long gone since early 2011. Remove the
reference in the comment and reword it slightly.

Fixes: 51ba60c5bb3b ("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>

Correct trivial checkpatch warnings, mostly whitespace issues and
unbalanced braces.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

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>

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>

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>

Stale mentions of irq_task are left in the kerneldoc after its removal.
Remove them.

There is still one indirect mention left but commit 3c8bb90efb6e ("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>