2 * Copyright (C) 2016 by NXP Semiconductors Inc.
3 * Date & Time support for PCF2127 RTC
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
25 static int pcf2127_read_reg(struct udevice *dev, uint offset,
28 struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
32 /* Set the address of the start register to be read */
33 ret = dm_i2c_write(dev, offset, NULL, 0);
37 /* Read register's data */
38 msg.addr = chip->chip_addr;
39 msg.flags |= I2C_M_RD;
43 return dm_i2c_xfer(dev, &msg, 1);
46 static int pcf2127_rtc_set(struct udevice *dev, const struct rtc_time *tm)
51 /* hours, minutes and seconds */
52 buf[i++] = bin2bcd(tm->tm_sec);
53 buf[i++] = bin2bcd(tm->tm_min);
54 buf[i++] = bin2bcd(tm->tm_hour);
55 buf[i++] = bin2bcd(tm->tm_mday);
56 buf[i++] = tm->tm_wday & 0x07;
59 buf[i++] = bin2bcd(tm->tm_mon + 1);
62 buf[i++] = bin2bcd(tm->tm_year % 100);
64 /* write register's data */
65 ret = dm_i2c_write(dev, PCF2127_REG_SC, buf, i);
70 static int pcf2127_rtc_get(struct udevice *dev, struct rtc_time *tm)
73 uchar buf[10] = { PCF2127_REG_CTRL1 };
75 ret = pcf2127_read_reg(dev, PCF2127_REG_CTRL1, buf, sizeof(buf));
79 if (buf[PCF2127_REG_CTRL3] & 0x04)
80 puts("### Warning: RTC Low Voltage - date/time not reliable\n");
82 tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F);
83 tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F);
84 tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F);
85 tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F);
86 tm->tm_mon = bcd2bin(buf[PCF2127_REG_MO] & 0x1F) - 1;
87 tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]) + 1900;
88 if (tm->tm_year < 1970)
89 tm->tm_year += 100; /* assume we are in 1970...2069 */
90 tm->tm_wday = buf[PCF2127_REG_DW] & 0x07;
94 debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
95 tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
96 tm->tm_hour, tm->tm_min, tm->tm_sec);
101 static int pcf2127_rtc_reset(struct udevice *dev)
103 /*Doing nothing here*/
108 static const struct rtc_ops pcf2127_rtc_ops = {
109 .get = pcf2127_rtc_get,
110 .set = pcf2127_rtc_set,
111 .reset = pcf2127_rtc_reset,
114 static const struct udevice_id pcf2127_rtc_ids[] = {
115 { .compatible = "pcf2127-rtc" },
119 U_BOOT_DRIVER(rtc_pcf2127) = {
120 .name = "rtc-pcf2127",
122 .of_match = pcf2127_rtc_ids,
123 .ops = &pcf2127_rtc_ops,