1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2010
4 * Heiko Schocher, DENX Software Engineering, hs@denx.de
5 */
6 #include <common.h>
7 #include <command.h>
8 #include <i2c.h>
9 #include <rtc.h>
10
11 #define RTC_RV3029_CTRL1 0x00
12 #define RTC_RV3029_CTRL1_EERE (1 << 3)
13
14 #define RTC_RV3029_CTRL_STATUS 0x03
15 #define RTC_RV3029_CTRLS_EEBUSY (1 << 7)
16
17 #define RTC_RV3029_CTRL_RESET 0x04
18 #define RTC_RV3029_CTRL_SYS_R (1 << 4)
19
20 #define RTC_RV3029_CLOCK_PAGE 0x08
21 #define RTC_RV3029_PAGE_LEN 7
22
23 #define RV3029C2_W_SECONDS 0x00
24 #define RV3029C2_W_MINUTES 0x01
25 #define RV3029C2_W_HOURS 0x02
26 #define RV3029C2_W_DATE 0x03
27 #define RV3029C2_W_DAYS 0x04
28 #define RV3029C2_W_MONTHS 0x05
29 #define RV3029C2_W_YEARS 0x06
30
31 #define RV3029C2_REG_HR_12_24 (1 << 6) /* 24h/12h mode */
32 #define RV3029C2_REG_HR_PM (1 << 5) /* PM/AM bit in 12h mode */
33
34 #define RTC_RV3029_EEPROM_CTRL 0x30
35 #define RTC_RV3029_TRICKLE_1K (1 << 4)
36 #define RTC_RV3029_TRICKLE_5K (1 << 5)
37 #define RTC_RV3029_TRICKLE_20K (1 << 6)
38 #define RTC_RV3029_TRICKLE_80K (1 << 7)
39
rtc_get(struct rtc_time * tmp)40 int rtc_get( struct rtc_time *tmp )
41 {
42 int ret;
43 unsigned char buf[RTC_RV3029_PAGE_LEN];
44
45 ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CLOCK_PAGE, 1, buf, \
46 RTC_RV3029_PAGE_LEN);
47 if (ret) {
48 printf("%s: error reading RTC: %x\n", __func__, ret);
49 return -1;
50 }
51 tmp->tm_sec = bcd2bin( buf[RV3029C2_W_SECONDS] & 0x7f);
52 tmp->tm_min = bcd2bin( buf[RV3029C2_W_MINUTES] & 0x7f);
53 if (buf[RV3029C2_W_HOURS] & RV3029C2_REG_HR_12_24) {
54 /* 12h format */
55 tmp->tm_hour = bcd2bin(buf[RV3029C2_W_HOURS] & 0x1f);
56 if (buf[RV3029C2_W_HOURS] & RV3029C2_REG_HR_PM)
57 /* PM flag set */
58 tmp->tm_hour += 12;
59 } else
60 tmp->tm_hour = bcd2bin(buf[RV3029C2_W_HOURS] & 0x3f);
61
62 tmp->tm_mday = bcd2bin( buf[RV3029C2_W_DATE] & 0x3F );
63 tmp->tm_mon = bcd2bin( buf[RV3029C2_W_MONTHS] & 0x1F );
64 tmp->tm_wday = bcd2bin( buf[RV3029C2_W_DAYS] & 0x07 );
65 /* RTC supports only years > 1999 */
66 tmp->tm_year = bcd2bin( buf[RV3029C2_W_YEARS]) + 2000;
67 tmp->tm_yday = 0;
68 tmp->tm_isdst = 0;
69
70 debug( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
71 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
72 tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
73
74 return 0;
75 }
76
rtc_set(struct rtc_time * tmp)77 int rtc_set( struct rtc_time *tmp )
78 {
79 int ret;
80 unsigned char buf[RTC_RV3029_PAGE_LEN];
81
82 debug( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
83 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
84 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
85
86 if (tmp->tm_year < 2000) {
87 printf("RTC: year %d < 2000 not possible\n", tmp->tm_year);
88 return -1;
89 }
90 buf[RV3029C2_W_SECONDS] = bin2bcd(tmp->tm_sec);
91 buf[RV3029C2_W_MINUTES] = bin2bcd(tmp->tm_min);
92 buf[RV3029C2_W_HOURS] = bin2bcd(tmp->tm_hour);
93 /* set 24h format */
94 buf[RV3029C2_W_HOURS] &= ~RV3029C2_REG_HR_12_24;
95 buf[RV3029C2_W_DATE] = bin2bcd(tmp->tm_mday);
96 buf[RV3029C2_W_DAYS] = bin2bcd(tmp->tm_wday);
97 buf[RV3029C2_W_MONTHS] = bin2bcd(tmp->tm_mon);
98 tmp->tm_year -= 2000;
99 buf[RV3029C2_W_YEARS] = bin2bcd(tmp->tm_year);
100 ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CLOCK_PAGE, 1,
101 buf, RTC_RV3029_PAGE_LEN);
102
103 /* give the RTC some time to update */
104 udelay(1000);
105 return ret;
106 }
107
108 /* sets EERE-Bit (automatic EEPROM refresh) */
set_eere_bit(int state)109 static void set_eere_bit(int state)
110 {
111 unsigned char reg_ctrl1;
112
113 (void)i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
114 ®_ctrl1, 1);
115
116 if (state)
117 reg_ctrl1 |= RTC_RV3029_CTRL1_EERE;
118 else
119 reg_ctrl1 &= (~RTC_RV3029_CTRL1_EERE);
120
121 (void)i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
122 ®_ctrl1, 1);
123 }
124
125 /* waits until EEPROM page is no longer busy (times out after 10ms*loops) */
wait_eebusy(int loops)126 static int wait_eebusy(int loops)
127 {
128 int i;
129 unsigned char ctrl_status;
130
131 for (i = 0; i < loops; i++) {
132 (void)i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_STATUS,
133 1, &ctrl_status, 1);
134
135 if ((ctrl_status & RTC_RV3029_CTRLS_EEBUSY) == 0)
136 break;
137 udelay(10000);
138 }
139 return i;
140 }
141
rtc_reset(void)142 void rtc_reset (void)
143 {
144 unsigned char buf[RTC_RV3029_PAGE_LEN];
145
146 buf[0] = RTC_RV3029_CTRL_SYS_R;
147 (void)i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_RESET, 1,
148 buf, 1);
149
150 #if defined(CONFIG_SYS_RV3029_TCR)
151 /*
152 * because EEPROM_CTRL register is in EEPROM page it is necessary to
153 * disable automatic EEPROM refresh and check if EEPROM is busy
154 * before EEPORM_CTRL register may be accessed
155 */
156 set_eere_bit(0);
157 wait_eebusy(100);
158 /* read current trickle charger setting */
159 (void)i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_EEPROM_CTRL,
160 1, buf, 1);
161 /* enable automatic EEPROM refresh again */
162 set_eere_bit(1);
163
164 /*
165 * to minimize EEPROM access write trickle charger setting only if it
166 * differs from current value
167 */
168 if ((buf[0] & 0xF0) != CONFIG_SYS_RV3029_TCR) {
169 buf[0] = (buf[0] & 0x0F) | CONFIG_SYS_RV3029_TCR;
170 /*
171 * write trickle charger setting (disable autom. EEPROM
172 * refresh and wait until EEPROM is idle)
173 */
174 set_eere_bit(0);
175 wait_eebusy(100);
176 (void)i2c_write(CONFIG_SYS_I2C_RTC_ADDR,
177 RTC_RV3029_EEPROM_CTRL, 1, buf, 1);
178 /*
179 * it is necessary to wait 10ms before EEBUSY-Bit may be read
180 * (this is not documented in the data sheet yet, but the
181 * manufacturer recommends it)
182 */
183 udelay(10000);
184 /* wait until EEPROM write access is finished */
185 wait_eebusy(100);
186 set_eere_bit(1);
187 }
188 #endif
189 }
190