1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * (C) Copyright 2001 4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 5 */ 6 7 /* 8 * Generic RTC interface. 9 */ 10 #ifndef _RTC_H_ 11 #define _RTC_H_ 12 13 /* bcd<->bin functions are needed by almost all the RTC drivers, let's include 14 * it there instead of in evey single driver */ 15 16 #include <bcd.h> 17 #include <rtc_def.h> 18 19 #ifdef CONFIG_DM_RTC 20 21 struct rtc_ops { 22 /** 23 * get() - get the current time 24 * 25 * Returns the current time read from the RTC device. The driver 26 * is responsible for setting up every field in the structure. 27 * 28 * @dev: Device to read from 29 * @time: Place to put the time that is read 30 */ 31 int (*get)(struct udevice *dev, struct rtc_time *time); 32 33 /** 34 * set() - set the current time 35 * 36 * Sets the time in the RTC device. The driver can expect every 37 * field to be set correctly. 38 * 39 * @dev: Device to read from 40 * @time: Time to write 41 */ 42 int (*set)(struct udevice *dev, const struct rtc_time *time); 43 44 /** 45 * reset() - reset the RTC to a known-good state 46 * 47 * This function resets the RTC to a known-good state. The time may 48 * be unset by this method, so should be set after this method is 49 * called. 50 * 51 * @dev: Device to read from 52 * @return 0 if OK, -ve on error 53 */ 54 int (*reset)(struct udevice *dev); 55 56 /** 57 * read8() - Read an 8-bit register 58 * 59 * @dev: Device to read from 60 * @reg: Register to read 61 * @return value read, or -ve on error 62 */ 63 int (*read8)(struct udevice *dev, unsigned int reg); 64 65 /** 66 * write8() - Write an 8-bit register 67 * 68 * @dev: Device to write to 69 * @reg: Register to write 70 * @value: Value to write 71 * @return 0 if OK, -ve on error 72 */ 73 int (*write8)(struct udevice *dev, unsigned int reg, int val); 74 }; 75 76 /* Access the operations for an RTC device */ 77 #define rtc_get_ops(dev) ((struct rtc_ops *)(dev)->driver->ops) 78 79 /** 80 * dm_rtc_get() - Read the time from an RTC 81 * 82 * @dev: Device to read from 83 * @time: Place to put the current time 84 * @return 0 if OK, -ve on error 85 */ 86 int dm_rtc_get(struct udevice *dev, struct rtc_time *time); 87 88 /** 89 * dm_rtc_set() - Write a time to an RTC 90 * 91 * @dev: Device to read from 92 * @time: Time to write into the RTC 93 * @return 0 if OK, -ve on error 94 */ 95 int dm_rtc_set(struct udevice *dev, struct rtc_time *time); 96 97 /** 98 * dm_rtc_reset() - reset the RTC to a known-good state 99 * 100 * If the RTC appears to be broken (e.g. it is not counting up in seconds) 101 * it may need to be reset to a known good state. This function achieves this. 102 * After resetting the RTC the time should then be set to a known value by 103 * the caller. 104 * 105 * @dev: Device to read from 106 * @return 0 if OK, -ve on error 107 */ 108 int dm_rtc_reset(struct udevice *dev); 109 110 /** 111 * rtc_read8() - Read an 8-bit register 112 * 113 * @dev: Device to read from 114 * @reg: Register to read 115 * @return value read, or -ve on error 116 */ 117 int rtc_read8(struct udevice *dev, unsigned int reg); 118 119 /** 120 * rtc_write8() - Write an 8-bit register 121 * 122 * @dev: Device to write to 123 * @reg: Register to write 124 * @value: Value to write 125 * @return 0 if OK, -ve on error 126 */ 127 int rtc_write8(struct udevice *dev, unsigned int reg, int val); 128 129 /** 130 * rtc_read16() - Read a 16-bit value from the RTC 131 * 132 * @dev: Device to read from 133 * @reg: Offset to start reading from 134 * @valuep: Place to put the value that is read 135 * @return 0 if OK, -ve on error 136 */ 137 int rtc_read16(struct udevice *dev, unsigned int reg, u16 *valuep); 138 139 /** 140 * rtc_write16() - Write a 16-bit value to the RTC 141 * 142 * @dev: Device to write to 143 * @reg: Register to start writing to 144 * @value: Value to write 145 * @return 0 if OK, -ve on error 146 */ 147 int rtc_write16(struct udevice *dev, unsigned int reg, u16 value); 148 149 /** 150 * rtc_read32() - Read a 32-bit value from the RTC 151 * 152 * @dev: Device to read from 153 * @reg: Offset to start reading from 154 * @valuep: Place to put the value that is read 155 * @return 0 if OK, -ve on error 156 */ 157 int rtc_read32(struct udevice *dev, unsigned int reg, u32 *valuep); 158 159 /** 160 * rtc_write32() - Write a 32-bit value to the RTC 161 * 162 * @dev: Device to write to 163 * @reg: Register to start writing to 164 * @value: Value to write 165 * @return 0 if OK, -ve on error 166 */ 167 int rtc_write32(struct udevice *dev, unsigned int reg, u32 value); 168 169 #else 170 int rtc_get (struct rtc_time *); 171 int rtc_set (struct rtc_time *); 172 void rtc_reset (void); 173 void rtc_enable_32khz_output(void); 174 175 /** 176 * rtc_read8() - Read an 8-bit register 177 * 178 * @reg: Register to read 179 * @return value read 180 */ 181 int rtc_read8(int reg); 182 183 /** 184 * rtc_write8() - Write an 8-bit register 185 * 186 * @reg: Register to write 187 * @value: Value to write 188 */ 189 void rtc_write8(int reg, uchar val); 190 191 /** 192 * rtc_read32() - Read a 32-bit value from the RTC 193 * 194 * @reg: Offset to start reading from 195 * @return value read 196 */ 197 u32 rtc_read32(int reg); 198 199 /** 200 * rtc_write32() - Write a 32-bit value to the RTC 201 * 202 * @reg: Register to start writing to 203 * @value: Value to write 204 */ 205 void rtc_write32(int reg, u32 value); 206 207 /** 208 * rtc_init() - Set up the real time clock ready for use 209 */ 210 void rtc_init(void); 211 #endif /* CONFIG_DM_RTC */ 212 213 /** 214 * is_leap_year - Check if year is a leap year 215 * 216 * @year Year 217 * @return 1 if leap year 218 */ 219 static inline bool is_leap_year(unsigned int year) 220 { 221 return (!(year % 4) && (year % 100)) || !(year % 400); 222 } 223 224 /** 225 * rtc_calc_weekday() - Work out the weekday from a time 226 * 227 * This only works for the Gregorian calendar - i.e. after 1752 (in the UK). 228 * It sets time->tm_wdaay to the correct day of the week. 229 * 230 * @time: Time to inspect. tm_wday is updated 231 * @return 0 if OK, -EINVAL if the weekday could not be determined 232 */ 233 int rtc_calc_weekday(struct rtc_time *time); 234 235 /** 236 * rtc_to_tm() - Convert a time_t value into a broken-out time 237 * 238 * The following fields are set up by this function: 239 * tm_sec, tm_min, tm_hour, tm_mday, tm_mon, tm_year, tm_wday 240 * 241 * Note that tm_yday and tm_isdst are set to 0. 242 * 243 * @time_t: Number of seconds since 1970-01-01 00:00:00 244 * @time: Place to put the broken-out time 245 */ 246 void rtc_to_tm(u64 time_t, struct rtc_time *time); 247 248 /** 249 * rtc_mktime() - Convert a broken-out time into a time_t value 250 * 251 * The following fields need to be valid for this function to work: 252 * tm_sec, tm_min, tm_hour, tm_mday, tm_mon, tm_year 253 * 254 * Note that tm_wday and tm_yday are ignored. 255 * 256 * @time: Broken-out time to convert 257 * @return corresponding time_t value, seconds since 1970-01-01 00:00:00 258 */ 259 unsigned long rtc_mktime(const struct rtc_time *time); 260 261 #endif /* _RTC_H_ */ 262