aboutsummaryrefslogtreecommitdiffstats
path: root/roms/u-boot/drivers/rtc/max6900.c
diff options
context:
space:
mode:
Diffstat (limited to 'roms/u-boot/drivers/rtc/max6900.c')
-rw-r--r--roms/u-boot/drivers/rtc/max6900.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/rtc/max6900.c b/roms/u-boot/drivers/rtc/max6900.c
new file mode 100644
index 000000000..11928839d
--- /dev/null
+++ b/roms/u-boot/drivers/rtc/max6900.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2004
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ */
+
+/*
+ * Date & Time support for MAXIM MAX6900 RTC
+ */
+
+/* #define DEBUG */
+
+#include <common.h>
+#include <command.h>
+#include <rtc.h>
+#include <i2c.h>
+#include <linux/delay.h>
+
+#ifndef CONFIG_SYS_I2C_RTC_ADDR
+#define CONFIG_SYS_I2C_RTC_ADDR 0x50
+#endif
+
+/* ------------------------------------------------------------------------- */
+
+static uchar rtc_read (uchar reg)
+{
+ return (i2c_reg_read (CONFIG_SYS_I2C_RTC_ADDR, reg));
+}
+
+static void rtc_write (uchar reg, uchar val)
+{
+ i2c_reg_write (CONFIG_SYS_I2C_RTC_ADDR, reg, val);
+ udelay(2500);
+}
+
+/* ------------------------------------------------------------------------- */
+
+int rtc_get (struct rtc_time *tmp)
+{
+ uchar sec, min, hour, mday, wday, mon, cent, year;
+ int retry = 1;
+
+ do {
+ sec = rtc_read (0x80);
+ min = rtc_read (0x82);
+ hour = rtc_read (0x84);
+ mday = rtc_read (0x86);
+ mon = rtc_read (0x88);
+ wday = rtc_read (0x8a);
+ year = rtc_read (0x8c);
+ cent = rtc_read (0x92);
+ /*
+ * Check for seconds rollover
+ */
+ if ((sec != 59) || (rtc_read(0x80) == sec)){
+ retry = 0;
+ }
+ } while (retry);
+
+ debug ( "Get RTC year: %02x mon: %02x cent: %02x mday: %02x wday: %02x "
+ "hr: %02x min: %02x sec: %02x\n",
+ year, mon, cent, mday, wday,
+ hour, min, sec );
+
+ tmp->tm_sec = bcd2bin (sec & 0x7F);
+ tmp->tm_min = bcd2bin (min & 0x7F);
+ tmp->tm_hour = bcd2bin (hour & 0x3F);
+ tmp->tm_mday = bcd2bin (mday & 0x3F);
+ tmp->tm_mon = bcd2bin (mon & 0x1F);
+ tmp->tm_year = bcd2bin (year) + bcd2bin(cent) * 100;
+ tmp->tm_wday = bcd2bin (wday & 0x07);
+ tmp->tm_yday = 0;
+ tmp->tm_isdst= 0;
+
+ debug ( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
+ tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
+ tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+ return 0;
+}
+
+int rtc_set (struct rtc_time *tmp)
+{
+
+ debug ( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
+ tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
+ tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
+
+ rtc_write (0x9E, 0x00);
+ rtc_write (0x80, 0); /* Clear seconds to ensure no rollover */
+ rtc_write (0x92, bin2bcd(tmp->tm_year / 100));
+ rtc_write (0x8c, bin2bcd(tmp->tm_year % 100));
+ rtc_write (0x8a, bin2bcd(tmp->tm_wday));
+ rtc_write (0x88, bin2bcd(tmp->tm_mon));
+ rtc_write (0x86, bin2bcd(tmp->tm_mday));
+ rtc_write (0x84, bin2bcd(tmp->tm_hour));
+ rtc_write (0x82, bin2bcd(tmp->tm_min ));
+ rtc_write (0x80, bin2bcd(tmp->tm_sec ));
+
+ return 0;
+}
+
+void rtc_reset (void)
+{
+}