This add support for the MediaTek MT2712 RTC. It was SoC based RTC, but
had different architecture compared with MT7622 RTC.
Signed-off-by: Ran Bi <ran.bi@mediatek.com>
Link: https://lore.kernel.org/r/20200226051303.22560-3-ran.bi@mediatek.com
Link: https://lore.kernel.org/r/20200316104701.209293-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Document the binding for MT2712 RTC implemented by rtc-mt2712.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Ran Bi <ran.bi@mediatek.com>
Link: https://lore.kernel.org/r/20200226051303.22560-2-ran.bi@mediatek.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

With the IOC3 MFD driver it's no longer necessary to special case SGI-IP27.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Link: https://lore.kernel.org/r/20200309123514.15543-1-tsbogend@alpha.franken.deSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Some boards, like OrangePi PC2 (H5), OrangePi Plus 2E (H3) and Tanix TX6
(H6) don't have external 32kHz oscillator. Till H6, it didn't really
matter if external oscillator was enabled because HW detected error and
fall back to internal one. H6 has same functionality but it's the first
SoC which have "auto switch bypass" bit documented and always enabled in
driver. This prevents RTC to work correctly if external crystal is not
present on board. There are other side effects - all peripherals which
depends on this clock also don't work (HDMI CEC for example).

Make clocks property optional. If it is present, select external
oscillator. If not, stay on internal.
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20200308135849.106333-2-jernej.skrabec@siol.netSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306010240.40056-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This RTC is a 32bit seconds counter.

Link: https://lore.kernel.org/r/20200306010240.40056-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200306010101.39517-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion to allow extending
support after 2106 and properly supporting the STv2 range.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200306005809.38530-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The PL031 and ST v1 RTC are 32bit seconds counters. STv2 is a BCD RTC
apparently going from 0000 to 9999, hopefully handling the leap days
properly until then.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200306005809.38530-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The core will never pass an invalid alarm to .set_alarm, it is not
necessary to check for its validity.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200306005809.38530-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Allow building building the driver with COMPILE_TEST.

Link: https://lore.kernel.org/r/20200306131629.18837-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306074404.58909-4-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The datasheet states that 4052 is the maximum value for year. However, the
mpc5121 read_time and set_time function abuse the target time register
instead of using the broken down time so it is limited to 2106.

Link: https://lore.kernel.org/r/20200306074404.58909-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This simplifies the path for the rtc_ops selection.

Link: https://lore.kernel.org/r/20200306074404.58909-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Use devm managed function to simplify probe and remove.

Link: https://lore.kernel.org/r/20200306074404.58909-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

rtc_time64_to_tm never generates an invalid rtc_tm, stop validating it.

Link: https://lore.kernel.org/r/20200306073758.58050-4-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306073758.58050-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The pm8xxx are 32bit seconds counter.

Link: https://lore.kernel.org/r/20200306073758.58050-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This allows further improvement of the driver. Also remove the unnecessary
error string as the core will already display error messages.

Link: https://lore.kernel.org/r/20200306073758.58050-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit version of rtc_tm to time conversion.

Link: https://lore.kernel.org/r/20200306073459.57197-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The ds1305 is a BCD rtc valid from 2000 to 2099.

Link: https://lore.kernel.org/r/20200306073459.57197-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306073404.56921-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The ds1374 is a 32bit seconds counter.

Link: https://lore.kernel.org/r/20200306073404.56921-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The RTC IRQ is requested before the struct rtc_device is allocated,
this may lead to a NULL pointer dereference in the IRQ handler.

To fix this issue, allocating the rtc_device struct before requesting
the RTC IRQ using devm_rtc_allocate_device, and use rtc_register_device
to register the RTC device.

Link: https://lore.kernel.org/r/20200306073404.56921-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306015703.42101-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The CPCAP rtc is a 14bit day counter plus a 17bit seconds counter.

Note that this failed on Nov 10 2014 so it is very likely this driver as
never been used since.

Link: https://lore.kernel.org/r/20200306015703.42101-2-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/20200306015703.42101-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306010146.39762-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The SA1100 RTC is a 32bit seconds counter.

Link: https://lore.kernel.org/r/20200306010146.39762-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Both RTC IRQs are requested before the struct rtc_device is allocated,
this may lead to a NULL pointer dereference in the IRQ handler.

To fix this issue, allocating the rtc_device struct before requesting
the IRQs using devm_rtc_allocate_device, and use rtc_register_device
to register the RTC device.

Link: https://lore.kernel.org/r/20200306010146.39762-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306005958.39203-4-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The Alchemy counter0 is a 32bit seconds counter.

Link: https://lore.kernel.org/r/20200306005958.39203-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Simplify the driver by removing the goto label as it only does return ret.

Link: https://lore.kernel.org/r/20200306005958.39203-2-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/20200306005958.39203-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit version of rtc_tm time conversion.

Link: https://lore.kernel.org/r/20200306005910.38939-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The starfire RTC is a 32bit seconds counter.

Link: https://lore.kernel.org/r/20200306005910.38939-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Call the 64bit versions of rtc_tm time conversion to avoid the y2106 issue.

Link: https://lore.kernel.org/r/20200306005730.38268-3-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The core will never pass an invalid alarm to .set_alarm, it is not
necessary to check for its validity.

Link: https://lore.kernel.org/r/20200306005730.38268-2-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This RTC is a 32bit seconds counter.

Link: https://lore.kernel.org/r/20200306005730.38268-1-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

convertfromdays and convert2days never return errors, stop handling non
existent errors.

Link: https://lore.kernel.org/r/20200305215022.32533-4-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>