When alarm value is read at boot time, at91_alarm_year is not yet set to
the proper value so the year is always set to 1900.

This results in that kind of message at boot:
rtc rtc0: invalid alarm value: 1900-1-14 2:11:39

There is no way to recover from that as the alarm is now only read when
booting.

Instead, rely on the rtc core to figure out the proper year.

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Calculating yday in the read_alarm callback is useless as this value is
never used later. Also, it was buggy anyway because at the time this is
done, tm_year is always 0 as the alarm register doesn't hold the year.

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

While highly unlikely, it is possible to get an interrupt as soon as it is
requested. In that case, at91_rtc_interrupt() will be called with rtc ==
NULL.

Solve that by using devm_rtc_allocate_device/rtc_register_device.

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

As said in the SAMA5D2 datasheet, "Prior to instructing the device
to enter ULP mode 1, ... and the internal sources of wake-up must
be cleared."

This patch is to clear the RTC alarm status flag prior to suspending
to avoid the erroneous wake-up activity, as it is often used as
the wake-up source for the ULP mode 1.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system
hang") added a workaround for the slow clock as it is not properly handled
by its users.

Get and use the slow clock as it is necessary for the at91rm9200 rtc.

Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

Sort included headers alphabetically.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Change the __raw IO calls to readl/write_relaxed which makes the driver
endian agnostic to run properly on big endian systems.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Andrew Victor <linux@maxim.org.za>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There is a typo here so we deadlock.

Fixes: dd1f1f391dd7 ('rtc: at91rm9200: rework wakeup and interrupt handling')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: David Dueck <davidcdueck@googlemail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The IRQ line used by the RTC device is usually shared with the system
timer (PIT) on at91 platforms.

Since timers are registering their handlers with IRQF_NO_SUSPEND, we
should expect being called in suspended state, and properly wake the
system up when this is the case.

Set IRQF_COND_SUSPEND flag when registering the IRQ handler to inform
irq core that it can safely be called while the system is suspended.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>