xref: /openbmc/u-boot/drivers/rtc/pcf2127.c (revision 8f3a8428c96cb8424afea68f86df83a4e07d63ff)
1*8f3a8428SMeng Yi /*
2*8f3a8428SMeng Yi  * Copyright (C) 2016 by NXP Semiconductors Inc.
3*8f3a8428SMeng Yi  * Date & Time support for PCF2127 RTC
4*8f3a8428SMeng Yi  */
5*8f3a8428SMeng Yi 
6*8f3a8428SMeng Yi /*	#define	DEBUG	*/
7*8f3a8428SMeng Yi 
8*8f3a8428SMeng Yi #include <common.h>
9*8f3a8428SMeng Yi #include <command.h>
10*8f3a8428SMeng Yi #include <dm.h>
11*8f3a8428SMeng Yi #include <i2c.h>
12*8f3a8428SMeng Yi #include <rtc.h>
13*8f3a8428SMeng Yi 
14*8f3a8428SMeng Yi #define PCF2127_REG_CTRL1	(0x00)
15*8f3a8428SMeng Yi #define PCF2127_REG_CTRL2	(0x01)
16*8f3a8428SMeng Yi #define PCF2127_REG_CTRL3	(0x02)
17*8f3a8428SMeng Yi #define PCF2127_REG_SC		(0x03)  /* datetime */
18*8f3a8428SMeng Yi #define PCF2127_REG_MN		(0x04)
19*8f3a8428SMeng Yi #define PCF2127_REG_HR		(0x05)
20*8f3a8428SMeng Yi #define PCF2127_REG_DM		(0x06)
21*8f3a8428SMeng Yi #define PCF2127_REG_DW		(0x07)
22*8f3a8428SMeng Yi #define PCF2127_REG_MO		(0x08)
23*8f3a8428SMeng Yi #define PCF2127_REG_YR		(0x09)
24*8f3a8428SMeng Yi 
25*8f3a8428SMeng Yi static int pcf2127_rtc_set(struct udevice *dev, const struct rtc_time *tm)
26*8f3a8428SMeng Yi {
27*8f3a8428SMeng Yi 	uchar buf[8];
28*8f3a8428SMeng Yi 	int i = 0;
29*8f3a8428SMeng Yi 
30*8f3a8428SMeng Yi 	/* start register address */
31*8f3a8428SMeng Yi 	buf[i++] = PCF2127_REG_SC;
32*8f3a8428SMeng Yi 
33*8f3a8428SMeng Yi 	/* hours, minutes and seconds */
34*8f3a8428SMeng Yi 	buf[i++] = bin2bcd(tm->tm_sec);
35*8f3a8428SMeng Yi 	buf[i++] = bin2bcd(tm->tm_min);
36*8f3a8428SMeng Yi 	buf[i++] = bin2bcd(tm->tm_hour);
37*8f3a8428SMeng Yi 	buf[i++] = bin2bcd(tm->tm_mday);
38*8f3a8428SMeng Yi 	buf[i++] = tm->tm_wday & 0x07;
39*8f3a8428SMeng Yi 
40*8f3a8428SMeng Yi 	/* month, 1 - 12 */
41*8f3a8428SMeng Yi 	buf[i++] = bin2bcd(tm->tm_mon + 1);
42*8f3a8428SMeng Yi 
43*8f3a8428SMeng Yi 	/* year */
44*8f3a8428SMeng Yi 	buf[i++] = bin2bcd(tm->tm_year % 100);
45*8f3a8428SMeng Yi 
46*8f3a8428SMeng Yi 	/* write register's data */
47*8f3a8428SMeng Yi 	if (dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, sizeof(buf)) < 0)
48*8f3a8428SMeng Yi 		return -1;
49*8f3a8428SMeng Yi 
50*8f3a8428SMeng Yi 	return 0;
51*8f3a8428SMeng Yi }
52*8f3a8428SMeng Yi 
53*8f3a8428SMeng Yi static int pcf2127_rtc_get(struct udevice *dev, struct rtc_time *tm)
54*8f3a8428SMeng Yi {
55*8f3a8428SMeng Yi 	int rel = 0;
56*8f3a8428SMeng Yi 	uchar buf[10] = { PCF2127_REG_CTRL1 };
57*8f3a8428SMeng Yi 
58*8f3a8428SMeng Yi 	if (dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, 1) < 0)
59*8f3a8428SMeng Yi 		return -1;
60*8f3a8428SMeng Yi 	if (dm_i2c_read(dev, PCF2127_REG_CTRL1, buf, sizeof(buf)) < 0)
61*8f3a8428SMeng Yi 		return -1;
62*8f3a8428SMeng Yi 
63*8f3a8428SMeng Yi 	if (buf[PCF2127_REG_CTRL3] & 0x04)
64*8f3a8428SMeng Yi 		puts("### Warning: RTC Low Voltage - date/time not reliable\n");
65*8f3a8428SMeng Yi 
66*8f3a8428SMeng Yi 	tm->tm_sec  = bcd2bin(buf[PCF2127_REG_SC] & 0x7F);
67*8f3a8428SMeng Yi 	tm->tm_min  = bcd2bin(buf[PCF2127_REG_MN] & 0x7F);
68*8f3a8428SMeng Yi 	tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F);
69*8f3a8428SMeng Yi 	tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F);
70*8f3a8428SMeng Yi 	tm->tm_mon  = bcd2bin(buf[PCF2127_REG_MO] & 0x1F) - 1;
71*8f3a8428SMeng Yi 	tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]) + 1900;
72*8f3a8428SMeng Yi 	if (tm->tm_year < 1970)
73*8f3a8428SMeng Yi 		tm->tm_year += 100;	/* assume we are in 1970...2069 */
74*8f3a8428SMeng Yi 	tm->tm_wday = buf[PCF2127_REG_DW] & 0x07;
75*8f3a8428SMeng Yi 	tm->tm_yday = 0;
76*8f3a8428SMeng Yi 	tm->tm_isdst = 0;
77*8f3a8428SMeng Yi 
78*8f3a8428SMeng Yi 	debug("Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
79*8f3a8428SMeng Yi 	      tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
80*8f3a8428SMeng Yi 	      tm->tm_hour, tm->tm_min, tm->tm_sec);
81*8f3a8428SMeng Yi 
82*8f3a8428SMeng Yi 	return rel;
83*8f3a8428SMeng Yi }
84*8f3a8428SMeng Yi 
85*8f3a8428SMeng Yi static int pcf2127_rtc_reset(struct udevice *dev)
86*8f3a8428SMeng Yi {
87*8f3a8428SMeng Yi 	/*Doing nothing here*/
88*8f3a8428SMeng Yi 	return 0;
89*8f3a8428SMeng Yi }
90*8f3a8428SMeng Yi 
91*8f3a8428SMeng Yi static const struct rtc_ops pcf2127_rtc_ops = {
92*8f3a8428SMeng Yi 	.get = pcf2127_rtc_get,
93*8f3a8428SMeng Yi 	.set = pcf2127_rtc_set,
94*8f3a8428SMeng Yi 	.reset = pcf2127_rtc_reset,
95*8f3a8428SMeng Yi };
96*8f3a8428SMeng Yi 
97*8f3a8428SMeng Yi static const struct udevice_id pcf2127_rtc_ids[] = {
98*8f3a8428SMeng Yi 	{ .compatible = "pcf2127-rtc" },
99*8f3a8428SMeng Yi 	{ }
100*8f3a8428SMeng Yi };
101*8f3a8428SMeng Yi 
102*8f3a8428SMeng Yi U_BOOT_DRIVER(rtc_pcf2127) = {
103*8f3a8428SMeng Yi 	.name	= "rtc-pcf2127",
104*8f3a8428SMeng Yi 	.id	= UCLASS_RTC,
105*8f3a8428SMeng Yi 	.of_match = pcf2127_rtc_ids,
106*8f3a8428SMeng Yi 	.ops	= &pcf2127_rtc_ops,
107*8f3a8428SMeng Yi };
108