1 /* 2 * (C) Copyright 2001 3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 /* 9 * Generic RTC interface. 10 */ 11 #ifndef _RTC_H_ 12 #define _RTC_H_ 13 14 /* bcd<->bin functions are needed by almost all the RTC drivers, let's include 15 * it there instead of in evey single driver */ 16 17 #include <bcd.h> 18 #include <rtc_def.h> 19 20 #ifdef CONFIG_DM_RTC 21 22 struct rtc_ops { 23 /** 24 * get() - get the current time 25 * 26 * Returns the current time read from the RTC device. The driver 27 * is responsible for setting up every field in the structure. 28 * 29 * @dev: Device to read from 30 * @time: Place to put the time that is read 31 */ 32 int (*get)(struct udevice *dev, struct rtc_time *time); 33 34 /** 35 * set() - set the current time 36 * 37 * Sets the time in the RTC device. The driver can expect every 38 * field to be set correctly. 39 * 40 * @dev: Device to read from 41 * @time: Time to write 42 */ 43 int (*set)(struct udevice *dev, const struct rtc_time *time); 44 45 /** 46 * reset() - reset the RTC to a known-good state 47 * 48 * This function resets the RTC to a known-good state. The time may 49 * be unset by this method, so should be set after this method is 50 * called. 51 * 52 * @dev: Device to read from 53 * @return 0 if OK, -ve on error 54 */ 55 int (*reset)(struct udevice *dev); 56 57 /** 58 * read8() - Read an 8-bit register 59 * 60 * @dev: Device to read from 61 * @reg: Register to read 62 * @return value read, or -ve on error 63 */ 64 int (*read8)(struct udevice *dev, unsigned int reg); 65 66 /** 67 * write8() - Write an 8-bit register 68 * 69 * @dev: Device to write to 70 * @reg: Register to write 71 * @value: Value to write 72 * @return 0 if OK, -ve on error 73 */ 74 int (*write8)(struct udevice *dev, unsigned int reg, int val); 75 }; 76 77 /* Access the operations for an RTC device */ 78 #define rtc_get_ops(dev) ((struct rtc_ops *)(dev)->driver->ops) 79 80 /** 81 * dm_rtc_get() - Read the time from an RTC 82 * 83 * @dev: Device to read from 84 * @time: Place to put the current time 85 * @return 0 if OK, -ve on error 86 */ 87 int dm_rtc_get(struct udevice *dev, struct rtc_time *time); 88 89 /** 90 * dm_rtc_put() - Write a time to an RTC 91 * 92 * @dev: Device to read from 93 * @time: Time to write into the RTC 94 * @return 0 if OK, -ve on error 95 */ 96 int dm_rtc_set(struct udevice *dev, struct rtc_time *time); 97 98 /** 99 * dm_rtc_reset() - reset the RTC to a known-good state 100 * 101 * If the RTC appears to be broken (e.g. it is not counting up in seconds) 102 * it may need to be reset to a known good state. This function achieves this. 103 * After resetting the RTC the time should then be set to a known value by 104 * the caller. 105 * 106 * @dev: Device to read from 107 * @return 0 if OK, -ve on error 108 */ 109 int dm_rtc_reset(struct udevice *dev); 110 111 /** 112 * rtc_read8() - Read an 8-bit register 113 * 114 * @dev: Device to read from 115 * @reg: Register to read 116 * @return value read, or -ve on error 117 */ 118 int rtc_read8(struct udevice *dev, unsigned int reg); 119 120 /** 121 * rtc_write8() - Write an 8-bit register 122 * 123 * @dev: Device to write to 124 * @reg: Register to write 125 * @value: Value to write 126 * @return 0 if OK, -ve on error 127 */ 128 int rtc_write8(struct udevice *dev, unsigned int reg, int val); 129 130 /** 131 * rtc_read32() - Read a 32-bit value from the RTC 132 * 133 * @dev: Device to read from 134 * @reg: Offset to start reading from 135 * @valuep: Place to put the value that is read 136 * @return 0 if OK, -ve on error 137 */ 138 int rtc_read32(struct udevice *dev, unsigned int reg, u32 *valuep); 139 140 /** 141 * rtc_write32() - Write a 32-bit value to the RTC 142 * 143 * @dev: Device to write to 144 * @reg: Register to start writing to 145 * @value: Value to write 146 * @return 0 if OK, -ve on error 147 */ 148 int rtc_write32(struct udevice *dev, unsigned int reg, u32 value); 149 150 #else 151 int rtc_get (struct rtc_time *); 152 int rtc_set (struct rtc_time *); 153 void rtc_reset (void); 154 155 /** 156 * rtc_read8() - Read an 8-bit register 157 * 158 * @reg: Register to read 159 * @return value read 160 */ 161 int rtc_read8(int reg); 162 163 /** 164 * rtc_write8() - Write an 8-bit register 165 * 166 * @reg: Register to write 167 * @value: Value to write 168 */ 169 void rtc_write8(int reg, uchar val); 170 171 /** 172 * rtc_read32() - Read a 32-bit value from the RTC 173 * 174 * @reg: Offset to start reading from 175 * @return value read 176 */ 177 u32 rtc_read32(int reg); 178 179 /** 180 * rtc_write32() - Write a 32-bit value to the RTC 181 * 182 * @reg: Register to start writing to 183 * @value: Value to write 184 */ 185 void rtc_write32(int reg, u32 value); 186 187 /** 188 * rtc_init() - Set up the real time clock ready for use 189 */ 190 void rtc_init(void); 191 #endif 192 193 /** 194 * rtc_calc_weekday() - Work out the weekday from a time 195 * 196 * This only works for the Gregorian calendar - i.e. after 1752 (in the UK). 197 * It sets time->tm_wdaay to the correct day of the week. 198 * 199 * @time: Time to inspect. tm_wday is updated 200 * @return 0 if OK, -EINVAL if the weekday could not be determined 201 */ 202 int rtc_calc_weekday(struct rtc_time *time); 203 204 /** 205 * rtc_to_tm() - Convert a time_t value into a broken-out time 206 * 207 * The following fields are set up by this function: 208 * tm_sec, tm_min, tm_hour, tm_mday, tm_mon, tm_year, tm_wday 209 * 210 * Note that tm_yday and tm_isdst are set to 0. 211 * 212 * @time_t: Number of seconds since 1970-01-01 00:00:00 213 * @time: Place to put the broken-out time 214 * @return 0 if OK, -EINVAL if the weekday could not be determined 215 */ 216 int rtc_to_tm(int time_t, struct rtc_time *time); 217 218 /** 219 * rtc_mktime() - Convert a broken-out time into a time_t value 220 * 221 * The following fields need to be valid for this function to work: 222 * tm_sec, tm_min, tm_hour, tm_mday, tm_mon, tm_year 223 * 224 * Note that tm_wday and tm_yday are ignored. 225 * 226 * @time: Broken-out time to convert 227 * @return corresponding time_t value, seconds since 1970-01-01 00:00:00 228 */ 229 unsigned long rtc_mktime(const struct rtc_time *time); 230 231 #endif /* _RTC_H_ */ 232