rtc: Modify rtc_hctosys() to address y2038 issues

rtc_hctosys() has a number of y2038 issues.

This patch resolves them by:
- Replace rtc_tm_to_time() with y2038-safe rtc_tm_to_time64()
- Replace do_settimeofday() with y2038-safe do_settimeofday64()

After this patch, it should not have any remaining y2038 issues.

Cc: pang.xunlei <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Signed-off-by: Xunlei Pang <[email protected]>
Signed-off-by: John Stultz <[email protected]>

Author: Xunlei Pang

drivers/rtc/hctosys.c

@@ -26,7 +26,7 @@ static int __init rtc_hctosys(void)
 {
 	int err = -ENODEV;
 	struct rtc_time tm;
-	struct timespec tv = {
+	struct timespec64 tv64 = {
 		.tv_nsec = NSEC_PER_SEC >> 1,
 	};
 	struct rtc_device *rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE);
@@ -52,16 +52,16 @@ static int __init rtc_hctosys(void)
 		goto err_invalid;
 	}
 
-	rtc_tm_to_time(&tm, &tv.tv_sec);
+	tv64.tv_sec = rtc_tm_to_time64(&tm);
 
-	err = do_settimeofday(&tv);
+	err = do_settimeofday64(&tv64);
 
 	dev_info(rtc->dev.parent,
 		"setting system clock to "
-		"%d-%02d-%02d %02d:%02d:%02d UTC (%u)\n",
+		"%d-%02d-%02d %02d:%02d:%02d UTC (%lld)\n",
 		tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
 		tm.tm_hour, tm.tm_min, tm.tm_sec,
-		(unsigned int) tv.tv_sec);
+		(long long) tv64.tv_sec);
 
 err_invalid:
 err_read: