[PATCH v2 5/5] rtc: renesas-rtca3: Factor out year decoding helper

[Prabhakar]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

The logic to decode the year value from the hardware registers is
duplicated in both rtca3_read_time() and rtca3_read_alarm().

Introduce a helper rtca3_decode_year() to centralize this conversion.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Reviewed-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
Tested-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx> # on RZ/G3S
---
 drivers/rtc/rtc-renesas-rtca3.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/rtc/rtc-renesas-rtca3.c b/drivers/rtc/rtc-renesas-rtca3.c
index 97e7e65f59a5..b3875d041de5 100644
--- a/drivers/rtc/rtc-renesas-rtca3.c
+++ b/drivers/rtc/rtc-renesas-rtca3.c
@@ -228,12 +228,19 @@ static void rtca3_prepare_cntalrm_regs_for_read(struct rtca3_priv *priv, bool cn
 	}
 }
 
+static u32 rtca3_decode_year(u8 mask, u16 year)
+{
+	u8 y = FIELD_GET(mask, year);
+	u32 century = bcd2bin((y == 0x99) ? 0x19 : 0x20);
+
+	return (century * 100 + bcd2bin(y)) - 1900;
+}
+
 static int rtca3_read_time(struct device *dev, struct rtc_time *tm)
 {
 	struct rtca3_priv *priv = dev_get_drvdata(dev);
 	u8 sec, min, hour, wday, mday, month, tmp;
 	u8 trials = 0;
-	u32 year100;
 	u16 year;
 
 	guard(spinlock_irqsave)(&priv->lock);
@@ -274,9 +281,7 @@ static int rtca3_read_time(struct device *dev, struct rtc_time *tm)
 	tm->tm_wday = bcd2bin(FIELD_GET(RTCA3_RWKCNT_WK, wday));
 	tm->tm_mday = bcd2bin(FIELD_GET(RTCA3_RDAYCNT_DAY, mday));
 	tm->tm_mon = bcd2bin(FIELD_GET(RTCA3_RMONCNT_MONTH, month)) - 1;
-	year = FIELD_GET(RTCA3_RYRCNT_YEAR, year);
-	year100 = bcd2bin((year == 0x99) ? 0x19 : 0x20);
-	tm->tm_year = (year100 * 100 + bcd2bin(year)) - 1900;
+	tm->tm_year = rtca3_decode_year(RTCA3_RYRCNT_YEAR, year);
 
 	return 0;
 }
@@ -354,7 +359,6 @@ static int rtca3_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
 	struct rtca3_priv *priv = dev_get_drvdata(dev);
 	u8 sec, min, hour, wday, mday, month;
 	struct rtc_time *tm = &wkalrm->time;
-	u32 year100;
 	u16 year;
 
 	guard(spinlock_irqsave)(&priv->lock);
@@ -373,9 +377,7 @@ static int rtca3_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
 	tm->tm_wday = bcd2bin(FIELD_GET(RTCA3_RWKAR_DAYW, wday));
 	tm->tm_mday = bcd2bin(FIELD_GET(RTCA3_RDAYAR_DATE, mday));
 	tm->tm_mon = bcd2bin(FIELD_GET(RTCA3_RMONAR_MON, month)) - 1;
-	year = FIELD_GET(RTCA3_RYRAR_YR, year);
-	year100 = bcd2bin((year == 0x99) ? 0x19 : 0x20);
-	tm->tm_year = (year100 * 100 + bcd2bin(year)) - 1900;
+	tm->tm_year = rtca3_decode_year(RTCA3_RYRAR_YR, year);
 
 	wkalrm->enabled = !!(readb(priv->base + RTCA3_RCR1) & RTCA3_RCR1_AIE);
 
-- 
2.54.0