rtc: pcf8523: let the core handle the alarm resolution

Set RTC_FEATURE_ALARM_RES_MINUTE, so the core knows alarms have a
resolution of a minute. Also, the core will properly round down the alarm
instead of up.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20220309162301.61679-15-alexandre.belloni@bootlin.com

drivers/rtc/rtc-pcf8523.c

@@ -212,14 +212,6 @@ static int pcf8523_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm)
 	if (err < 0)
 		return err;
 
-	/* The alarm has no seconds, round up to nearest minute */
-	if (tm->time.tm_sec) {
-		time64_t alarm_time = rtc_tm_to_time64(&tm->time);
-
-		alarm_time += 60 - tm->time.tm_sec;
-		rtc_time64_to_tm(alarm_time, &tm->time);
-	}
-
 	regs[0] = bin2bcd(tm->time.tm_min);
 	regs[1] = bin2bcd(tm->time.tm_hour);
 	regs[2] = bin2bcd(tm->time.tm_mday);
@@ -450,6 +442,7 @@ static int pcf8523_probe(struct i2c_client *client,
 	rtc->ops = &pcf8523_rtc_ops;
 	rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 	rtc->range_max = RTC_TIMESTAMP_END_2099;
+	set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->features);
 	clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features);
 
 	if (client->irq > 0) {