rtc: mt6397: refine RTC_TC_MTH

This patch adds RTC_TC_MTH_MASK to support new chips.
Signed-off-by: Yuchen Huang <yuchen.huang@mediatek.com>
Signed-off-by: Hsin-Hsiung Wang <hsin-hsiung.wang@mediatek.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/rtc/rtc-mt6397.c

@@ -75,7 +75,7 @@ static int __mtk_rtc_read_time(struct mt6397_rtc *rtc,
 	tm->tm_min = data[RTC_OFFSET_MIN];
 	tm->tm_hour = data[RTC_OFFSET_HOUR];
 	tm->tm_mday = data[RTC_OFFSET_DOM];
-	tm->tm_mon = data[RTC_OFFSET_MTH];
+	tm->tm_mon = data[RTC_OFFSET_MTH] & RTC_TC_MTH_MASK;
 	tm->tm_year = data[RTC_OFFSET_YEAR];
 
 	ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_TC_SEC, sec);

include/linux/mfd/mt6397/rtc.h

@@ -36,6 +36,7 @@
 #define RTC_AL_MASK_DOW                BIT(4)
 
 #define RTC_TC_SEC             0x000a
+#define RTC_TC_MTH_MASK        0x000f
 /* Min, Hour, Dom... register offset to RTC_TC_SEC */
 #define RTC_OFFSET_SEC         0
 #define RTC_OFFSET_MIN         1