The msm6242_set()/msm6242_clear() functions are used when writing to Control
Register D to set or clear the HOLD bit when reading the current time from
the RTC.

Doing this with a read-modify-write cycle will potentially clear an
interrupt condition which occurs between the read and the write.

The datasheet states the following about this:

  When writing the HOLD or 30 second adjust bits of register D, it is
  necessary to write the IRQ FLAG bit to a "1".

Since the only other bits in the register are the 30 second adjust bit
(which is not used) and the BUSY bit (which is read-only), the
read-modify-write cycle can be replaced by a simple write with the IRQ FLAG
bit set to 1 and the other bits (except HOLD) set to 0.
Tested-by: Kars de Jong <jongk@linux-m68k.org>
Signed-off-by: Kars de Jong <jongk@linux-m68k.org>
Link: https://lore.kernel.org/r/20191116114620.9193-1-jongk@linux-m68k.orgReviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The driver was reading the wrong register as the 10-hour digit due to
a misplaced ')'. It was in fact reading the 1-second digit register due
to this bug.

Also remove the use of a magic number for the hour mask and use the define
for it which was already present.

Fixes: 4f9b9bba ("rtc: Add an RTC driver for the Oki MSM6242")
Tested-by: Kars de Jong <jongk@linux-m68k.org>
Signed-off-by: Kars de Jong <jongk@linux-m68k.org>
Link: https://lore.kernel.org/r/20191116110548.8562-1-jongk@linux-m68k.orgReviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

If tps65910 INT1 pin (IRQ output) is not wired to any IRQ controller,
then it can't be used as system wakeup/alarm source,
but it is still possible to read/write time from/to RTC.
Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Link: https://lore.kernel.org/r/20191116203748.27166-1-andrej.skvortzov@gmail.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The Flextimer alarm is primarily used as a wakeup source for system
power management.  But it shouldn't select the power management driver
as they don't really have dependency of each other.

Also remove the default y as it is not a critical feature for the
systems.
Signed-off-by: Li Yang <leoyang.li@nxp.com>
Link: https://lore.kernel.org/r/1573252856-11759-1-git-send-email-leoyang.li@nxp.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The lates of clockout should be marked const. Make that so.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Link: https://lore.kernel.org/r/20191108002449.15097-1-iwamatsu@nigauri.orgSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

DRV_NAME is unused, remove it.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Link: https://lore.kernel.org/r/20191108002354.15016-1-iwamatsu@nigauri.orgSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Use SPDX-License-Identifier instead of a verbose license text.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Link: https://lore.kernel.org/r/20191108002250.14937-1-iwamatsu@nigauri.orgSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

rx6110_remove is empty, remove it.
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Link: https://lore.kernel.org/r/20191108002113.14791-1-iwamatsu@nigauri.orgSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

When using following operations:
date -s "21190910 19:20:00"
hwclock -w
to change date from 2019 to 2119 for test, it will fail on Hygon
Dhyana and AMD Zen CPUs, while the same operations run ok on Intel i7
platform.

MC146818 driver use function mc146818_set_time() to set register
RTC_FREQ_SELECT(RTC_REG_A)'s bit4-bit6 field which means divider stage
reset value on Intel platform to 0x7.

While AMD/Hygon RTC_REG_A(0Ah)'s bit4 is defined as DV0 [Reference]:
DV0 = 0 selects Bank 0, DV0 = 1 selects Bank 1. Bit5-bit6 is defined
as reserved.

DV0 is set to 1, it will select Bank 1, which will disable AltCentury
register(0x32) access. As UEFI pass acpi_gbl_FADT.century 0x32
(AltCentury), the CMOS write will be failed on code:
CMOS_WRITE(century, acpi_gbl_FADT.century).

Correct RTC_REG_A bank select bit(DV0) to 0 on AMD/Hygon CPUs, it will
enable AltCentury(0x32) register writing and finally setup century as
expected.

Test results on Intel i7, AMD EPYC(17h) and Hygon machine show that it
works as expected.
Compiling for sparc64 and alpha architectures are passed.

Reference:
https://www.amd.com/system/files/TechDocs/51192_Bolton_FCH_RRG.pdf
section: 3.13 Real Time Clock (RTC)
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Jinke Fan <fanjinke@hygon.cn>
Link: https://lore.kernel.org/r/20191105083943.115320-1-fanjinke@hygon.cnSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The module alias platform tag contains a spelling mistake. Fix it.

Fixes: f33506abbcdd ("rtc: bd70528: Add MODULE ALIAS to autoload module")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20191106083418.159045-1-colin.king@canonical.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The bd70528 RTC driver is probed by MFD driver. Add MODULE_ALIAS
in order to allow udev to load the module when MFD sub-device cell
for RTC is added.

I'm not sure if this is a bugfix or feature addition but I guess
fixes tag won't harm in this case.

Fixes: 32a4a4eb ("rtc: bd70528: Initial support for ROHM bd70528 RTC")
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/20191023114711.GA13954@localhost.localdomainSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The RTC month value is 1-indexed, but the kernel assumes it is 0-indexed.
This may result in the RTC not rolling over correctly.
Signed-off-by: Ilya Ledvich <ilya@compulab.co.il>
Reviewed-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Link: https://lore.kernel.org/r/20191101095422.14787-1-ilya@compulab.co.ilSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This driver forgets to disable and unprepare clock when remove.
Add a call to clk_disable_unprepare to fix it.

Fixes: c4f07ece ("rtc: brcmstb-waketimer: Add Broadcom STB wake-timer")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20191105160043.20018-1-hslester96@gmail.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Let the rtc core check the date/time against the RTC range.
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20191016201414.30934-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The RTC core now has error messages in case of registration failure, there
is no need to have other messages in the drivers.
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20191016201414.30934-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

dpm_sysfs_remove() and device_pm_remove() are already called by
device_del() on device removal so there is no need to call
device_init_wakeup(dev, false) from the driver and it allows to remove the
.remove callback.

Link: https://lore.kernel.org/r/20191021155806.3625-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

dpm_sysfs_remove() and device_pm_remove() are already called by
device_del() on device removal so there is no need to call
device_init_wakeup(dev, false) from the driver and it allows to remove the
.remove callback.

Link: https://lore.kernel.org/r/20191021155806.3625-4-alexandre.belloni@bootlin.comReviewed-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

dpm_sysfs_remove() and device_pm_remove() are already called by
device_del() on device removal so there is no need to call
device_init_wakeup(dev, false) from the driver and it allows to remove the
.remove callback.

Link: https://lore.kernel.org/r/20191021155806.3625-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

dpm_sysfs_remove() and device_pm_remove() are already called by
device_del() on device removal so there is no need to call
device_init_wakeup(dev, false) from the driver and it allows to remove the
.remove callback.

Link: https://lore.kernel.org/r/20191021155806.3625-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

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.comReported-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Reported-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

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: 6610e089 ("RTC: Rework RTC code to use timerqueue for events")
Link: https://lore.kernel.org/r/20191020231320.8191-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Directly call ktime_get_real_seconds instead of converting the result to a
struct rtc_time and then back to a time64_t.

Link: https://lore.kernel.org/r/20191016201223.30568-4-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion to avoid the y2038 issue.

Link: https://lore.kernel.org/r/20191016201223.30568-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The driver drops the nanoseconds part of the timespec64, there is no need
to call ktime_get_real_ts64.

Link: https://lore.kernel.org/r/20191016201223.30568-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Linux should handle when the pcf2127 watchdog feature is enabled by the
bootloader. This is done by checking the watchdog timer value during
init, and set the WDOG_HW_RUNNING flag if the value differs from zero.
Signed-off-by: Martin Hundebøll <martin@geanix.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191021080838.2789-1-martin@geanix.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

rv3028 provides clkout (enabled by default). Add clkout
to clock framework source and control from device tree for
variable frequency with enable and disable functionality.
Signed-off-by: Parthiban Nallathambi <pn@denx.de>
Link: https://lore.kernel.org/r/20191018100425.1687979-1-pn@denx.deSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

It is not necessary to call device_init_wakeup(dev, false) in .remove as
device_del will take care of that. It is also not necessary to
devm_free_irq. Finally, dev_pm_clear_wake_irq can be called
unconditionally.

Link: https://lore.kernel.org/r/20191019204941.6203-9-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Rework the interrupt handling to avoid caching the values as the core is
already doing that. The core also always ensures the rtc_time passed for
the alarm is fully populated.

The only trick is in read_alarm where status needs to be read before the
alarm registers to ensure the potential irq is not cleared.

Link: https://lore.kernel.org/r/20191019204941.6203-8-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Use rtc_lock and rtc_unlock to lock the rtc from the interrupt handler.
This removes the need for a driver specific lock.

Link: https://lore.kernel.org/r/20191019204941.6203-7-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Check whether regmap_read fails before continuing in the sysfs .show
callbacks.

Link: https://lore.kernel.org/r/20191019204941.6203-6-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Use regmap_update_bits to update DS1343_CONTROL_REG in a race free manner
when setting the glitch filter.

Link: https://lore.kernel.org/r/20191019204941.6203-5-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Use rtc_add_group to add the sysfs group in a race free manner.
This has the side effect of moving the files to their proper location.

Link: https://lore.kernel.org/r/20191019204941.6203-4-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

To avoid possible race condition, use regmap_bulk_write to write all the
date/time registers at once instead of sequentially.

Link: https://lore.kernel.org/r/20191019204941.6203-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

RTC_SET_CHARGE doesn't exist, the ioctl code is never used.

Link: https://lore.kernel.org/r/20191019204941.6203-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This is a standard BCD rtc with a useless century bit (no leap year
correction after 2099).

Link: https://lore.kernel.org/r/20191019204941.6203-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Introduce rtc_lock and rtc_unlock to shorten the code when locking and
unlocking ops_lock from drivers.

Link: https://lore.kernel.org/r/20191019205034.6382-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Let the rtc core check the date/time against the RTC range.

Link: https://lore.kernel.org/r/20191016201626.31309-5-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This allows further improvement of the driver.

Link: https://lore.kernel.org/r/20191016201626.31309-4-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The RTC core now has error messages in case of registration failure, there
is no need to have other messages in the drivers.

Link: https://lore.kernel.org/r/20191016201626.31309-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

err_return doesn't do anything special, simply return instead of goto.

Link: https://lore.kernel.org/r/20191016201626.31309-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>