rtc: tps6586x: remove mktime usage

The tps6586x use a 64-bit 'epoch_start' value, but then computes that
value using an 'mktime()', which has a smaller range and overflows
in 2106 at the latest. As both the hardware and the subsystem interface
support wider than 32-bit ranges for rtc times here, let's change all
the operations on 'seconds' to time64_t.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

drivers/rtc/rtc-tps6586x.c

@@ -58,7 +58,7 @@ struct tps6586x_rtc {
 	struct rtc_device	*rtc;
 	int			irq;
 	bool			irq_en;
-	unsigned long long	epoch_start;
+	time64_t		epoch_start;
 };
 
 static inline struct device *to_tps6586x_dev(struct device *dev)
@@ -71,7 +71,7 @@ static int tps6586x_rtc_read_time(struct device *dev, struct rtc_time *tm)
 	struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
 	struct device *tps_dev = to_tps6586x_dev(dev);
 	unsigned long long ticks = 0;
-	unsigned long seconds;
+	time64_t seconds;
 	u8 buff[6];
 	int ret;
 	int i;
@@ -98,11 +98,11 @@ static int tps6586x_rtc_set_time(struct device *dev, struct rtc_time *tm)
 	struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
 	struct device *tps_dev = to_tps6586x_dev(dev);
 	unsigned long long ticks;
-	unsigned long seconds;
+	time64_t seconds;
 	u8 buff[5];
 	int ret;
 
-	rtc_tm_to_time(tm, &seconds);
+	seconds = rtc_tm_to_time64(tm);
 	if (seconds < rtc->epoch_start) {
 		dev_err(dev, "requested time unsupported\n");
 		return -EINVAL;
@@ -157,7 +157,7 @@ static int tps6586x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
 	struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
 	struct device *tps_dev = to_tps6586x_dev(dev);
-	unsigned long seconds;
+	time64_t seconds;
 	unsigned long ticks;
 	unsigned long rtc_current_time;
 	unsigned long long rticks = 0;
@@ -166,7 +166,7 @@ static int tps6586x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	int ret;
 	int i;
 
-	rtc_tm_to_time(&alrm->time, &seconds);
+	seconds = rtc_tm_to_time64(&alrm->time);
 
 	if (alrm->enabled && (seconds < rtc->epoch_start)) {
 		dev_err(dev, "can't set alarm to requested time\n");
@@ -213,7 +213,7 @@ static int tps6586x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	struct tps6586x_rtc *rtc = dev_get_drvdata(dev);
 	struct device *tps_dev = to_tps6586x_dev(dev);
 	unsigned long ticks;
-	unsigned long seconds;
+	time64_t seconds;
 	u8 buff[3];
 	int ret;
 
@@ -227,7 +227,7 @@ static int tps6586x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	seconds = ticks >> 10;
 	seconds += rtc->epoch_start;
 
-	rtc_time_to_tm(seconds, &alrm->time);
+	rtc_time64_to_tm(seconds, &alrm->time);
 	return 0;
 }
 
@@ -261,7 +261,7 @@ static int tps6586x_rtc_probe(struct platform_device *pdev)
 	rtc->irq = platform_get_irq(pdev, 0);
 
 	/* Set epoch start as 00:00:00:01:01:2009 */
-	rtc->epoch_start = mktime(2009, 1, 1, 0, 0, 0);
+	rtc->epoch_start = mktime64(2009, 1, 1, 0, 0, 0);
 
 	/* 1 kHz tick mode, enable tick counting */
 	ret = tps6586x_update(tps_dev, RTC_CTRL,