1 /*
2 * Copyright (C) 2016 by NXP Semiconductors Inc.
3 * Date & Time support for PCF2127 RTC
4 */
5
6 /* #define DEBUG */
7
8 #include <common.h>
9 #include <command.h>
10 #include <dm.h>
11 #include <i2c.h>
12 #include <rtc.h>
13
14 #define PCF2127_REG_CTRL1 0x00
15 #define PCF2127_REG_CTRL2 0x01
16 #define PCF2127_REG_CTRL3 0x02
17 #define PCF2127_REG_SC 0x03
18 #define PCF2127_REG_MN 0x04
19 #define PCF2127_REG_HR 0x05
20 #define PCF2127_REG_DM 0x06
21 #define PCF2127_REG_DW 0x07
22 #define PCF2127_REG_MO 0x08
23 #define PCF2127_REG_YR 0x09
24
pcf2127_rtc_set(struct udevice * dev,const struct rtc_time * tm)25 static int pcf2127_rtc_set(struct udevice *dev, const struct rtc_time *tm)
26 {
27 uchar buf[8];
28 int i = 0, ret;
29
30 /* start register address */
31 buf[i++] = PCF2127_REG_SC;
32
33 /* hours, minutes and seconds */
34 buf[i++] = bin2bcd(tm->tm_sec);
35 buf[i++] = bin2bcd(tm->tm_min);
36 buf[i++] = bin2bcd(tm->tm_hour);
37 buf[i++] = bin2bcd(tm->tm_mday);
38 buf[i++] = tm->tm_wday & 0x07;
39
40 /* month, 1 - 12 */
41 buf[i++] = bin2bcd(tm->tm_mon + 1);
42
43 /* year */
44 buf[i++] = bin2bcd(tm->tm_year % 100);
45
46 /* write register's data */
47 ret = dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, sizeof(buf));
48
49 return ret;
50 }
51
pcf2127_rtc_get(struct udevice * dev,struct rtc_time * tm)52 static int pcf2127_rtc_get(struct udevice *dev, struct rtc_time *tm)
53 {
54 int ret = 0;
55 uchar buf[10] = { PCF2127_REG_CTRL1 };
56
57 ret = dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, 1);
58 if (ret < 0)
59 return ret;
60 ret = dm_i2c_read(dev, PCF2127_REG_CTRL1, buf, sizeof(buf));
61 if (ret < 0)
62 return ret;
63
64 if (buf[PCF2127_REG_CTRL3] & 0x04)
65 puts("### Warning: RTC Low Voltage - date/time not reliable\n");
66
67 tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F);
68 tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F);
69 tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F);
70 tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F);
71 tm->tm_mon = bcd2bin(buf[PCF2127_REG_MO] & 0x1F) - 1;
72 tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]) + 1900;
73 if (tm->tm_year < 1970)
74 tm->tm_year += 100; /* assume we are in 1970...2069 */
75 tm->tm_wday = buf[PCF2127_REG_DW] & 0x07;
76 tm->tm_yday = 0;
77 tm->tm_isdst = 0;
78
79 debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
80 tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
81 tm->tm_hour, tm->tm_min, tm->tm_sec);
82
83 return ret;
84 }
85
pcf2127_rtc_reset(struct udevice * dev)86 static int pcf2127_rtc_reset(struct udevice *dev)
87 {
88 /*Doing nothing here*/
89
90 return 0;
91 }
92
93 static const struct rtc_ops pcf2127_rtc_ops = {
94 .get = pcf2127_rtc_get,
95 .set = pcf2127_rtc_set,
96 .reset = pcf2127_rtc_reset,
97 };
98
99 static const struct udevice_id pcf2127_rtc_ids[] = {
100 { .compatible = "pcf2127-rtc" },
101 { }
102 };
103
104 U_BOOT_DRIVER(rtc_pcf2127) = {
105 .name = "rtc-pcf2127",
106 .id = UCLASS_RTC,
107 .of_match = pcf2127_rtc_ids,
108 .ops = &pcf2127_rtc_ops,
109 };
110