1 /* 2 * M41T80 serial rtc emulation 3 * 4 * Copyright (c) 2018 BALATON Zoltan 5 * 6 * This work is licensed under the GNU GPL license version 2 or later. 7 * 8 */ 9 10 #include "qemu/osdep.h" 11 #include "qemu-common.h" 12 #include "qemu/log.h" 13 #include "qemu/module.h" 14 #include "qemu/timer.h" 15 #include "qemu/bcd.h" 16 #include "hw/i2c/i2c.h" 17 #include "qom/object.h" 18 19 #define TYPE_M41T80 "m41t80" 20 typedef struct M41t80State M41t80State; 21 #define M41T80(obj) OBJECT_CHECK(M41t80State, (obj), TYPE_M41T80) 22 23 struct M41t80State { 24 I2CSlave parent_obj; 25 int8_t addr; 26 }; 27 28 static void m41t80_realize(DeviceState *dev, Error **errp) 29 { 30 M41t80State *s = M41T80(dev); 31 32 s->addr = -1; 33 } 34 35 static int m41t80_send(I2CSlave *i2c, uint8_t data) 36 { 37 M41t80State *s = M41T80(i2c); 38 39 if (s->addr < 0) { 40 s->addr = data; 41 } else { 42 s->addr++; 43 } 44 return 0; 45 } 46 47 static uint8_t m41t80_recv(I2CSlave *i2c) 48 { 49 M41t80State *s = M41T80(i2c); 50 struct tm now; 51 qemu_timeval tv; 52 53 if (s->addr < 0) { 54 s->addr = 0; 55 } 56 if (s->addr >= 1 && s->addr <= 7) { 57 qemu_get_timedate(&now, -1); 58 } 59 switch (s->addr++) { 60 case 0: 61 qemu_gettimeofday(&tv); 62 return to_bcd(tv.tv_usec / 10000); 63 case 1: 64 return to_bcd(now.tm_sec); 65 case 2: 66 return to_bcd(now.tm_min); 67 case 3: 68 return to_bcd(now.tm_hour); 69 case 4: 70 return to_bcd(now.tm_wday); 71 case 5: 72 return to_bcd(now.tm_mday); 73 case 6: 74 return to_bcd(now.tm_mon + 1); 75 case 7: 76 return to_bcd(now.tm_year % 100); 77 case 8 ... 19: 78 qemu_log_mask(LOG_UNIMP, "%s: unimplemented register: %d\n", 79 __func__, s->addr - 1); 80 return 0; 81 default: 82 qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid register: %d\n", 83 __func__, s->addr - 1); 84 return 0; 85 } 86 } 87 88 static int m41t80_event(I2CSlave *i2c, enum i2c_event event) 89 { 90 M41t80State *s = M41T80(i2c); 91 92 if (event == I2C_START_SEND) { 93 s->addr = -1; 94 } 95 return 0; 96 } 97 98 static void m41t80_class_init(ObjectClass *klass, void *data) 99 { 100 DeviceClass *dc = DEVICE_CLASS(klass); 101 I2CSlaveClass *sc = I2C_SLAVE_CLASS(klass); 102 103 dc->realize = m41t80_realize; 104 sc->send = m41t80_send; 105 sc->recv = m41t80_recv; 106 sc->event = m41t80_event; 107 } 108 109 static const TypeInfo m41t80_info = { 110 .name = TYPE_M41T80, 111 .parent = TYPE_I2C_SLAVE, 112 .instance_size = sizeof(M41t80State), 113 .class_init = m41t80_class_init, 114 }; 115 116 static void m41t80_register_types(void) 117 { 118 type_register_static(&m41t80_info); 119 } 120 121 type_init(m41t80_register_types) 122