rtc: add support for Abracon AB-RTCMC-32.768kHz-B5ZE-S3 I2C RTC chip

This patch adds support for Abracon AB-RTCMC-32.768kHz-B5ZE-S3
RTC/Calendar module w/ I2C interface.

This support includes RTC time reading and setting, Alarm (1 minute
accuracy) reading and setting, and battery low detection.  The device also
supports frequency adjustment and two timers but those features are
currently not implemented in this driver.  Due to alarm accuracy
limitation (and current lack of timer support in the driver), UIE mode is
not supported.

Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Peter Huewe <peter.huewe@infineon.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robherring2@gmail.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Landley <rob@landley.net>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Kumar Gala <galak@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index 9f41d05..f9463b4 100644 (file)
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -9,6 +9,7 @@ document for it just like any other devices.
 
 Compatible             Vendor / Chip
 ==========             =============
+abracon,abb5zes3               AB-RTCMC-32.768kHz-B5ZE-S3: Real Time Clock/Calendar Module with I2C Interface
 ad,ad7414              SMBus/I2C Digital Temperature Sensor in 6-Pin SOT with SMBus Alert and Over Temperature Pin
 ad,adm9240             ADM9240:  Complete System Hardware Monitor for uProcessor-Based Systems
 adi,adt7461            +/-1C TDM Extended Temp Range I.C

diff --cc drivers/rtc/Kconfig
Simple merge

diff --cc drivers/rtc/Makefile
Simple merge

diff --cc drivers/rtc/rtc-ab-b5ze-s3.c
Simple merge