From 2b1d401296950517143d90533df232f754dbb13b Mon Sep 17 00:00:00 2001
From: "S.J.R. van Schaik" <stephan@whiteboxsystems.nl>
Date: Thu, 27 Jul 2017 12:24:42 +0200
Subject: [PATCH] stm32f0: rtc: fix off by one

---
 source/platform/stm32f0/rtc.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/source/platform/stm32f0/rtc.c b/source/platform/stm32f0/rtc.c
index 6d76eec..cf2eb65 100644
--- a/source/platform/stm32f0/rtc.c
+++ b/source/platform/stm32f0/rtc.c
@@ -60,11 +60,13 @@ int rtc_get_time(struct tm *time)
 	time->tm_min  += (unsigned char)(((rtc_tr >> 12) & 0xF) * 10);
 	time->tm_hour  = (unsigned char)((rtc_tr >> 16) & 0xF);
 	time->tm_hour += (unsigned char)(((rtc_tr >> 20) & 0xF) * 10);
+	time->tm_hour -= 1;
 
 	time->tm_mday   = (unsigned char)(rtc_dr & 0xF);
 	time->tm_mday  += (unsigned char)(((rtc_dr >> 4) & 0x3) * 10);
 	time->tm_mon   = (unsigned char)((rtc_dr >> 8) & 0xF);
 	time->tm_mon  += (unsigned char)(((rtc_dr >> 12) & 0x1) * 10);
+	time->tm_mon  -= 1;
 	time->tm_year  = (unsigned char)((rtc_dr >> 16) & 0xF);
 	time->tm_year += (unsigned char)(((rtc_dr >> 20) & 0xF) * 10);
 	time->tm_year += 100;
@@ -75,24 +77,26 @@ int rtc_get_time(struct tm *time)
 static int rtc_set_time(struct tm *time)
 {
 	uint32_t rtc_tr, rtc_dr;
-	uint32_t year;
+	uint32_t hour, mon, year;
 
 	if (!time)
 		return -1;
 
+	hour = time->tm_hour + 1;
+	mon = time->tm_mon + 1;
 	year = time->tm_year - 100;
 
-	rtc_tr  = (time->tm_sec  % 10);
-	rtc_tr |= (time->tm_sec  / 10) << 4;
-	rtc_tr |= (time->tm_min  % 10) << 8;
-	rtc_tr |= (time->tm_min  / 10) << 12;
-	rtc_tr |= (time->tm_hour % 10) << 16;
-	rtc_tr |= (time->tm_hour / 10) << 20;
+	rtc_tr  = (time->tm_sec % 10);
+	rtc_tr |= (time->tm_sec / 10) << 4;
+	rtc_tr |= (time->tm_min % 10) << 8;
+	rtc_tr |= (time->tm_min / 10) << 12;
+	rtc_tr |= (hour % 10) << 16;
+	rtc_tr |= (hour / 10) << 20;
 
 	rtc_dr  = (time->tm_mday % 10);
 	rtc_dr |= (time->tm_mday / 10) << 4;
-	rtc_dr |= (time->tm_mon  % 10) << 8;
-	rtc_dr |= (time->tm_mon  / 10) << 12;
+	rtc_dr |= (mon  % 10) << 8;
+	rtc_dr |= (mon  / 10) << 12;
 	rtc_dr |= (year % 10) << 16;
 	rtc_dr |= (year / 10) << 20;