projects / qemu.git / blame
| Commit | Line | Data |
|---|---|---|
| 1dfe3943 PB |
1 | /* |
| 2 | * MAXIM DS1338 I2C RTC+NVRAM | |
| 3 | * | |
| 4 | * Copyright (c) 2009 CodeSourcery. | |
| 5 | * Written by Paul Brook | |
| 6 | * | |
| 8e31bf38 | 7 | * This code is licensed under the GNU GPL v2. |
| 1dfe3943 PB |
8 | */ |
| 9 | ||
| 10 | #include "i2c.h" | |
| 11 | ||
| 12 | typedef struct { | |
| 13 | i2c_slave i2c; | |
| 14 | time_t offset; | |
| 15 | struct tm now; | |
| 16 | uint8_t nvram[56]; | |
| 17 | int ptr; | |
| 18 | int addr_byte; | |
| 19 | } DS1338State; | |
| 20 | ||
| 21 | static void ds1338_event(i2c_slave *i2c, enum i2c_event event) | |
| 22 | { | |
| 23 | DS1338State *s = FROM_I2C_SLAVE(DS1338State, i2c); | |
| 24 | ||
| 25 | switch (event) { | |
| 26 | case I2C_START_RECV: | |
| 27 | qemu_get_timedate(&s->now, s->offset); | |
| 28 | s->nvram[0] = to_bcd(s->now.tm_sec); | |
| 29 | s->nvram[1] = to_bcd(s->now.tm_min); | |
| 30 | if (s->nvram[2] & 0x40) { | |
| 31 | s->nvram[2] = (to_bcd((s->now.tm_hour % 12)) + 1) | 0x40; | |
| 32 | if (s->now.tm_hour >= 12) { | |
| 33 | s->nvram[2] |= 0x20; | |
| 34 | } | |
| 35 | } else { | |
| 36 | s->nvram[2] = to_bcd(s->now.tm_hour); | |
| 37 | } | |
| 38 | s->nvram[3] = to_bcd(s->now.tm_wday) + 1; | |
| 39 | s->nvram[4] = to_bcd(s->now.tm_mday); | |
| 40 | s->nvram[5] = to_bcd(s->now.tm_mon) + 1; | |
| 41 | s->nvram[6] = to_bcd(s->now.tm_year - 100); | |
| 42 | break; | |
| 43 | case I2C_START_SEND: | |
| 44 | s->addr_byte = 1; | |
| 45 | break; | |
| 46 | default: | |
| 47 | break; | |
| 48 | } | |
| 49 | } | |
| 50 | ||
| 51 | static int ds1338_recv(i2c_slave *i2c) | |
| 52 | { | |
| 53 | DS1338State *s = FROM_I2C_SLAVE(DS1338State, i2c); | |
| 54 | uint8_t res; | |
| 55 | ||
| 56 | res = s->nvram[s->ptr]; | |
| 57 | s->ptr = (s->ptr + 1) & 0xff; | |
| 58 | return res; | |
| 59 | } | |
| 60 | ||
| 61 | static int ds1338_send(i2c_slave *i2c, uint8_t data) | |
| 62 | { | |
| 63 | DS1338State *s = FROM_I2C_SLAVE(DS1338State, i2c); | |
| 64 | if (s->addr_byte) { | |
| 65 | s->ptr = data; | |
| 66 | s->addr_byte = 0; | |
| 67 | return 0; | |
| 68 | } | |
| 69 | s->nvram[s->ptr - 8] = data; | |
| 70 | if (data < 8) { | |
| 71 | qemu_get_timedate(&s->now, s->offset); | |
| 72 | switch(data) { | |
| 73 | case 0: | |
| 74 | /* TODO: Implement CH (stop) bit. */ | |
| 75 | s->now.tm_sec = from_bcd(data & 0x7f); | |
| 76 | break; | |
| 77 | case 1: | |
| 78 | s->now.tm_min = from_bcd(data & 0x7f); | |
| 79 | break; | |
| 80 | case 2: | |
| 81 | if (data & 0x40) { | |
| 82 | if (data & 0x20) { | |
| 83 | data = from_bcd(data & 0x4f) + 11; | |
| 84 | } else { | |
| 85 | data = from_bcd(data & 0x1f) - 1; | |
| 86 | } | |
| 87 | } else { | |
| 88 | data = from_bcd(data); | |
| 89 | } | |
| 90 | s->now.tm_hour = data; | |
| 91 | break; | |
| 92 | case 3: | |
| 93 | s->now.tm_wday = from_bcd(data & 7) - 1; | |
| 94 | break; | |
| 95 | case 4: | |
| 96 | s->now.tm_mday = from_bcd(data & 0x3f); | |
| 97 | break; | |
| 98 | case 5: | |
| 99 | s->now.tm_mon = from_bcd(data & 0x1f) - 1; | |
| 100 | case 6: | |
| 101 | s->now.tm_year = from_bcd(data) + 100; | |
| 102 | break; | |
| 103 | case 7: | |
| 104 | /* Control register. Currently ignored. */ | |
| 105 | break; | |
| 106 | } | |
| 107 | s->offset = qemu_timedate_diff(&s->now); | |
| 108 | } | |
| 109 | s->ptr = (s->ptr + 1) & 0xff; | |
| 110 | return 0; | |
| 111 | } | |
| 112 | ||
| 113 | static int ds1338_init(i2c_slave *i2c) | |
| 114 | { | |
| 115 | return 0; | |
| 116 | } | |
| 117 | ||
| 118 | static I2CSlaveInfo ds1338_info = { | |
| 119 | .qdev.name = "ds1338", | |
| 120 | .qdev.size = sizeof(DS1338State), | |
| 121 | .init = ds1338_init, | |
| 122 | .event = ds1338_event, | |
| 123 | .recv = ds1338_recv, | |
| 124 | .send = ds1338_send, | |
| 125 | }; | |
| 126 | ||
| 127 | static void ds1338_register_devices(void) | |
| 128 | { | |
| 129 | i2c_register_slave(&ds1338_info); | |
| 130 | } | |
| 131 | ||
| 132 | device_init(ds1338_register_devices) |