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 <log.h>
13 #include <rtc.h>
14
15 #define PCF2127_REG_CTRL1 0x00
16 #define PCF2127_REG_CTRL2 0x01
17 #define PCF2127_REG_CTRL3 0x02
18 #define PCF2127_REG_SC 0x03
19 #define PCF2127_REG_MN 0x04
20 #define PCF2127_REG_HR 0x05
21 #define PCF2127_REG_DM 0x06
22 #define PCF2127_REG_DW 0x07
23 #define PCF2127_REG_MO 0x08
24 #define PCF2127_REG_YR 0x09
25
pcf2127_rtc_read(struct udevice * dev,uint offset,u8 * buffer,uint len)26 static int pcf2127_rtc_read(struct udevice *dev, uint offset, u8 *buffer, uint len)
27 {
28 struct dm_i2c_chip *chip = dev_get_parent_plat(dev);
29 struct i2c_msg msg;
30 int ret;
31
32 /* Set the address of the start register to be read */
33 ret = dm_i2c_write(dev, offset, NULL, 0);
34 if (ret < 0)
35 return ret;
36
37 /* Read register's data */
38 msg.addr = chip->chip_addr;
39 msg.flags |= I2C_M_RD;
40 msg.len = len;
41 msg.buf = buffer;
42
43 return dm_i2c_xfer(dev, &msg, 1);
44 }
45
pcf2127_rtc_write(struct udevice * dev,uint offset,const u8 * buffer,uint len)46 static int pcf2127_rtc_write(struct udevice *dev, uint offset,
47 const u8 *buffer, uint len)
48 {
49 return dm_i2c_write(dev, offset, buffer, len);
50 }
51
pcf2127_rtc_set(struct udevice * dev,const struct rtc_time * tm)52 static int pcf2127_rtc_set(struct udevice *dev, const struct rtc_time *tm)
53 {
54 uchar buf[7] = {0};
55 int i = 0, ret;
56
57 /* hours, minutes and seconds */
58 buf[i++] = bin2bcd(tm->tm_sec);
59 buf[i++] = bin2bcd(tm->tm_min);
60 buf[i++] = bin2bcd(tm->tm_hour);
61 buf[i++] = bin2bcd(tm->tm_mday);
62 buf[i++] = tm->tm_wday & 0x07;
63
64 /* month, 1 - 12 */
65 buf[i++] = bin2bcd(tm->tm_mon);
66
67 /* year */
68 buf[i++] = bin2bcd(tm->tm_year % 100);
69
70 /* write register's data */
71 ret = dm_i2c_write(dev, PCF2127_REG_SC, buf, i);
72
73 return ret;
74 }
75
pcf2127_rtc_get(struct udevice * dev,struct rtc_time * tm)76 static int pcf2127_rtc_get(struct udevice *dev, struct rtc_time *tm)
77 {
78 int ret = 0;
79 uchar buf[10] = { PCF2127_REG_CTRL1 };
80
81 ret = pcf2127_rtc_read(dev, PCF2127_REG_CTRL1, buf, sizeof(buf));
82 if (ret < 0)
83 return ret;
84
85 if (buf[PCF2127_REG_CTRL3] & 0x04)
86 puts("### Warning: RTC Low Voltage - date/time not reliable\n");
87
88 tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F);
89 tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F);
90 tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F);
91 tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F);
92 tm->tm_mon = bcd2bin(buf[PCF2127_REG_MO] & 0x1F);
93 tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]) + 1900;
94 if (tm->tm_year < 1970)
95 tm->tm_year += 100; /* assume we are in 1970...2069 */
96 tm->tm_wday = buf[PCF2127_REG_DW] & 0x07;
97 tm->tm_yday = 0;
98 tm->tm_isdst = 0;
99
100 debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
101 tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
102 tm->tm_hour, tm->tm_min, tm->tm_sec);
103
104 return ret;
105 }
106
pcf2127_rtc_reset(struct udevice * dev)107 static int pcf2127_rtc_reset(struct udevice *dev)
108 {
109 /*Doing nothing here*/
110
111 return 0;
112 }
113
114 static const struct rtc_ops pcf2127_rtc_ops = {
115 .get = pcf2127_rtc_get,
116 .set = pcf2127_rtc_set,
117 .reset = pcf2127_rtc_reset,
118 .read = pcf2127_rtc_read,
119 .write = pcf2127_rtc_write,
120 };
121
122 static const struct udevice_id pcf2127_rtc_ids[] = {
123 { .compatible = "pcf2127-rtc" },
124 { }
125 };
126
127 U_BOOT_DRIVER(rtc_pcf2127) = {
128 .name = "rtc-pcf2127",
129 .id = UCLASS_RTC,
130 .of_match = pcf2127_rtc_ids,
131 .ops = &pcf2127_rtc_ops,
132 };
133