| 1 | /* |
| 2 | * QEMU SMBus host (master) emulation. |
| 3 | * |
| 4 | * This code emulates SMBus transactions from the master point of view, |
| 5 | * it runs the individual I2C transaction to do the SMBus protocol |
| 6 | * over I2C. |
| 7 | * |
| 8 | * Copyright (c) 2007 CodeSourcery. |
| 9 | * Written by Paul Brook |
| 10 | * |
| 11 | * This code is licensed under the LGPL. |
| 12 | */ |
| 13 | |
| 14 | #include "qemu/osdep.h" |
| 15 | #include "hw/i2c/i2c.h" |
| 16 | #include "hw/i2c/smbus_master.h" |
| 17 | |
| 18 | /* Master device commands. */ |
| 19 | int smbus_quick_command(I2CBus *bus, uint8_t addr, int read) |
| 20 | { |
| 21 | if (i2c_start_transfer(bus, addr, read)) { |
| 22 | return -1; |
| 23 | } |
| 24 | i2c_end_transfer(bus); |
| 25 | return 0; |
| 26 | } |
| 27 | |
| 28 | int smbus_receive_byte(I2CBus *bus, uint8_t addr) |
| 29 | { |
| 30 | uint8_t data; |
| 31 | |
| 32 | if (i2c_start_recv(bus, addr)) { |
| 33 | return -1; |
| 34 | } |
| 35 | data = i2c_recv(bus); |
| 36 | i2c_nack(bus); |
| 37 | i2c_end_transfer(bus); |
| 38 | return data; |
| 39 | } |
| 40 | |
| 41 | int smbus_send_byte(I2CBus *bus, uint8_t addr, uint8_t data) |
| 42 | { |
| 43 | if (i2c_start_send(bus, addr)) { |
| 44 | return -1; |
| 45 | } |
| 46 | i2c_send(bus, data); |
| 47 | i2c_end_transfer(bus); |
| 48 | return 0; |
| 49 | } |
| 50 | |
| 51 | int smbus_read_byte(I2CBus *bus, uint8_t addr, uint8_t command) |
| 52 | { |
| 53 | uint8_t data; |
| 54 | if (i2c_start_send(bus, addr)) { |
| 55 | return -1; |
| 56 | } |
| 57 | i2c_send(bus, command); |
| 58 | if (i2c_start_recv(bus, addr)) { |
| 59 | i2c_end_transfer(bus); |
| 60 | return -1; |
| 61 | } |
| 62 | data = i2c_recv(bus); |
| 63 | i2c_nack(bus); |
| 64 | i2c_end_transfer(bus); |
| 65 | return data; |
| 66 | } |
| 67 | |
| 68 | int smbus_write_byte(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t data) |
| 69 | { |
| 70 | if (i2c_start_send(bus, addr)) { |
| 71 | return -1; |
| 72 | } |
| 73 | i2c_send(bus, command); |
| 74 | i2c_send(bus, data); |
| 75 | i2c_end_transfer(bus); |
| 76 | return 0; |
| 77 | } |
| 78 | |
| 79 | int smbus_read_word(I2CBus *bus, uint8_t addr, uint8_t command) |
| 80 | { |
| 81 | uint16_t data; |
| 82 | if (i2c_start_send(bus, addr)) { |
| 83 | return -1; |
| 84 | } |
| 85 | i2c_send(bus, command); |
| 86 | if (i2c_start_recv(bus, addr)) { |
| 87 | i2c_end_transfer(bus); |
| 88 | return -1; |
| 89 | } |
| 90 | data = i2c_recv(bus); |
| 91 | data |= i2c_recv(bus) << 8; |
| 92 | i2c_nack(bus); |
| 93 | i2c_end_transfer(bus); |
| 94 | return data; |
| 95 | } |
| 96 | |
| 97 | int smbus_write_word(I2CBus *bus, uint8_t addr, uint8_t command, uint16_t data) |
| 98 | { |
| 99 | if (i2c_start_send(bus, addr)) { |
| 100 | return -1; |
| 101 | } |
| 102 | i2c_send(bus, command); |
| 103 | i2c_send(bus, data & 0xff); |
| 104 | i2c_send(bus, data >> 8); |
| 105 | i2c_end_transfer(bus); |
| 106 | return 0; |
| 107 | } |
| 108 | |
| 109 | int smbus_read_block(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t *data, |
| 110 | int len, bool recv_len, bool send_cmd) |
| 111 | { |
| 112 | int rlen; |
| 113 | int i; |
| 114 | |
| 115 | if (send_cmd) { |
| 116 | if (i2c_start_send(bus, addr)) { |
| 117 | return -1; |
| 118 | } |
| 119 | i2c_send(bus, command); |
| 120 | } |
| 121 | if (i2c_start_recv(bus, addr)) { |
| 122 | if (send_cmd) { |
| 123 | i2c_end_transfer(bus); |
| 124 | } |
| 125 | return -1; |
| 126 | } |
| 127 | if (recv_len) { |
| 128 | rlen = i2c_recv(bus); |
| 129 | } else { |
| 130 | rlen = len; |
| 131 | } |
| 132 | if (rlen > len) { |
| 133 | rlen = 0; |
| 134 | } |
| 135 | for (i = 0; i < rlen; i++) { |
| 136 | data[i] = i2c_recv(bus); |
| 137 | } |
| 138 | i2c_nack(bus); |
| 139 | i2c_end_transfer(bus); |
| 140 | return rlen; |
| 141 | } |
| 142 | |
| 143 | int smbus_write_block(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t *data, |
| 144 | int len, bool send_len) |
| 145 | { |
| 146 | int i; |
| 147 | |
| 148 | if (len > 32) { |
| 149 | len = 32; |
| 150 | } |
| 151 | |
| 152 | if (i2c_start_send(bus, addr)) { |
| 153 | return -1; |
| 154 | } |
| 155 | i2c_send(bus, command); |
| 156 | if (send_len) { |
| 157 | i2c_send(bus, len); |
| 158 | } |
| 159 | for (i = 0; i < len; i++) { |
| 160 | i2c_send(bus, data[i]); |
| 161 | } |
| 162 | i2c_end_transfer(bus); |
| 163 | return 0; |
| 164 | } |