| /* |
| * QEMU SMBus device emulation. |
| * |
| * Copyright (c) 2007 CodeSourcery. |
| * Written by Paul Brook |
| * |
| * This code is licensed under the LGPL. |
| */ |
| |
| /* TODO: Implement PEC. */ |
| |
| #include "hw/hw.h" |
| #include "hw/i2c/i2c.h" |
| #include "hw/i2c/smbus.h" |
| |
| //#define DEBUG_SMBUS 1 |
| |
| #ifdef DEBUG_SMBUS |
| #define DPRINTF(fmt, ...) \ |
| do { printf("smbus(%02x): " fmt , dev->i2c.address, ## __VA_ARGS__); } while (0) |
| #define BADF(fmt, ...) \ |
| do { fprintf(stderr, "smbus: error: " fmt , ## __VA_ARGS__); exit(1);} while (0) |
| #else |
| #define DPRINTF(fmt, ...) do {} while(0) |
| #define BADF(fmt, ...) \ |
| do { fprintf(stderr, "smbus: error: " fmt , ## __VA_ARGS__);} while (0) |
| #endif |
| |
| enum { |
| SMBUS_IDLE, |
| SMBUS_WRITE_DATA, |
| SMBUS_RECV_BYTE, |
| SMBUS_READ_DATA, |
| SMBUS_DONE, |
| SMBUS_CONFUSED = -1 |
| }; |
| |
| static void smbus_do_quick_cmd(SMBusDevice *dev, int recv) |
| { |
| SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev); |
| |
| DPRINTF("Quick Command %d\n", recv); |
| if (sc->quick_cmd) { |
| sc->quick_cmd(dev, recv); |
| } |
| } |
| |
| static void smbus_do_write(SMBusDevice *dev) |
| { |
| SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev); |
| |
| if (dev->data_len == 0) { |
| smbus_do_quick_cmd(dev, 0); |
| } else if (dev->data_len == 1) { |
| DPRINTF("Send Byte\n"); |
| if (sc->send_byte) { |
| sc->send_byte(dev, dev->data_buf[0]); |
| } |
| } else { |
| dev->command = dev->data_buf[0]; |
| DPRINTF("Command %d len %d\n", dev->command, dev->data_len - 1); |
| if (sc->write_data) { |
| sc->write_data(dev, dev->command, dev->data_buf + 1, |
| dev->data_len - 1); |
| } |
| } |
| } |
| |
| static void smbus_i2c_event(I2CSlave *s, enum i2c_event event) |
| { |
| SMBusDevice *dev = SMBUS_DEVICE(s); |
| |
| switch (event) { |
| case I2C_START_SEND: |
| switch (dev->mode) { |
| case SMBUS_IDLE: |
| DPRINTF("Incoming data\n"); |
| dev->mode = SMBUS_WRITE_DATA; |
| break; |
| default: |
| BADF("Unexpected send start condition in state %d\n", dev->mode); |
| dev->mode = SMBUS_CONFUSED; |
| break; |
| } |
| break; |
| |
| case I2C_START_RECV: |
| switch (dev->mode) { |
| case SMBUS_IDLE: |
| DPRINTF("Read mode\n"); |
| dev->mode = SMBUS_RECV_BYTE; |
| break; |
| case SMBUS_WRITE_DATA: |
| if (dev->data_len == 0) { |
| BADF("Read after write with no data\n"); |
| dev->mode = SMBUS_CONFUSED; |
| } else { |
| if (dev->data_len > 1) { |
| smbus_do_write(dev); |
| } else { |
| dev->command = dev->data_buf[0]; |
| DPRINTF("%02x: Command %d\n", dev->i2c.address, |
| dev->command); |
| } |
| DPRINTF("Read mode\n"); |
| dev->data_len = 0; |
| dev->mode = SMBUS_READ_DATA; |
| } |
| break; |
| default: |
| BADF("Unexpected recv start condition in state %d\n", dev->mode); |
| dev->mode = SMBUS_CONFUSED; |
| break; |
| } |
| break; |
| |
| case I2C_FINISH: |
| switch (dev->mode) { |
| case SMBUS_WRITE_DATA: |
| smbus_do_write(dev); |
| break; |
| case SMBUS_RECV_BYTE: |
| smbus_do_quick_cmd(dev, 1); |
| break; |
| case SMBUS_READ_DATA: |
| BADF("Unexpected stop during receive\n"); |
| break; |
| default: |
| /* Nothing to do. */ |
| break; |
| } |
| dev->mode = SMBUS_IDLE; |
| dev->data_len = 0; |
| break; |
| |
| case I2C_NACK: |
| switch (dev->mode) { |
| case SMBUS_DONE: |
| /* Nothing to do. */ |
| break; |
| case SMBUS_READ_DATA: |
| dev->mode = SMBUS_DONE; |
| break; |
| default: |
| BADF("Unexpected NACK in state %d\n", dev->mode); |
| dev->mode = SMBUS_CONFUSED; |
| break; |
| } |
| } |
| } |
| |
| static int smbus_i2c_recv(I2CSlave *s) |
| { |
| SMBusDevice *dev = SMBUS_DEVICE(s); |
| SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev); |
| int ret; |
| |
| switch (dev->mode) { |
| case SMBUS_RECV_BYTE: |
| if (sc->receive_byte) { |
| ret = sc->receive_byte(dev); |
| } else { |
| ret = 0; |
| } |
| DPRINTF("Receive Byte %02x\n", ret); |
| dev->mode = SMBUS_DONE; |
| break; |
| case SMBUS_READ_DATA: |
| if (sc->read_data) { |
| ret = sc->read_data(dev, dev->command, dev->data_len); |
| dev->data_len++; |
| } else { |
| ret = 0; |
| } |
| DPRINTF("Read data %02x\n", ret); |
| break; |
| default: |
| BADF("Unexpected read in state %d\n", dev->mode); |
| dev->mode = SMBUS_CONFUSED; |
| ret = 0; |
| break; |
| } |
| return ret; |
| } |
| |
| static int smbus_i2c_send(I2CSlave *s, uint8_t data) |
| { |
| SMBusDevice *dev = SMBUS_DEVICE(s); |
| |
| switch (dev->mode) { |
| case SMBUS_WRITE_DATA: |
| DPRINTF("Write data %02x\n", data); |
| dev->data_buf[dev->data_len++] = data; |
| break; |
| default: |
| BADF("Unexpected write in state %d\n", dev->mode); |
| break; |
| } |
| return 0; |
| } |
| |
| static int smbus_device_init(I2CSlave *i2c) |
| { |
| SMBusDevice *dev = SMBUS_DEVICE(i2c); |
| SMBusDeviceClass *sc = SMBUS_DEVICE_GET_CLASS(dev); |
| |
| return sc->init(dev); |
| } |
| |
| /* Master device commands. */ |
| int smbus_quick_command(I2CBus *bus, uint8_t addr, int read) |
| { |
| if (i2c_start_transfer(bus, addr, read)) { |
| return -1; |
| } |
| i2c_end_transfer(bus); |
| return 0; |
| } |
| |
| int smbus_receive_byte(I2CBus *bus, uint8_t addr) |
| { |
| uint8_t data; |
| |
| if (i2c_start_transfer(bus, addr, 1)) { |
| return -1; |
| } |
| data = i2c_recv(bus); |
| i2c_nack(bus); |
| i2c_end_transfer(bus); |
| return data; |
| } |
| |
| int smbus_send_byte(I2CBus *bus, uint8_t addr, uint8_t data) |
| { |
| if (i2c_start_transfer(bus, addr, 0)) { |
| return -1; |
| } |
| i2c_send(bus, data); |
| i2c_end_transfer(bus); |
| return 0; |
| } |
| |
| int smbus_read_byte(I2CBus *bus, uint8_t addr, uint8_t command) |
| { |
| uint8_t data; |
| if (i2c_start_transfer(bus, addr, 0)) { |
| return -1; |
| } |
| i2c_send(bus, command); |
| i2c_start_transfer(bus, addr, 1); |
| data = i2c_recv(bus); |
| i2c_nack(bus); |
| i2c_end_transfer(bus); |
| return data; |
| } |
| |
| int smbus_write_byte(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t data) |
| { |
| if (i2c_start_transfer(bus, addr, 0)) { |
| return -1; |
| } |
| i2c_send(bus, command); |
| i2c_send(bus, data); |
| i2c_end_transfer(bus); |
| return 0; |
| } |
| |
| int smbus_read_word(I2CBus *bus, uint8_t addr, uint8_t command) |
| { |
| uint16_t data; |
| if (i2c_start_transfer(bus, addr, 0)) { |
| return -1; |
| } |
| i2c_send(bus, command); |
| i2c_start_transfer(bus, addr, 1); |
| data = i2c_recv(bus); |
| data |= i2c_recv(bus) << 8; |
| i2c_nack(bus); |
| i2c_end_transfer(bus); |
| return data; |
| } |
| |
| int smbus_write_word(I2CBus *bus, uint8_t addr, uint8_t command, uint16_t data) |
| { |
| if (i2c_start_transfer(bus, addr, 0)) { |
| return -1; |
| } |
| i2c_send(bus, command); |
| i2c_send(bus, data & 0xff); |
| i2c_send(bus, data >> 8); |
| i2c_end_transfer(bus); |
| return 0; |
| } |
| |
| int smbus_read_block(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t *data) |
| { |
| int len; |
| int i; |
| |
| if (i2c_start_transfer(bus, addr, 0)) { |
| return -1; |
| } |
| i2c_send(bus, command); |
| i2c_start_transfer(bus, addr, 1); |
| len = i2c_recv(bus); |
| if (len > 32) { |
| len = 0; |
| } |
| for (i = 0; i < len; i++) { |
| data[i] = i2c_recv(bus); |
| } |
| i2c_nack(bus); |
| i2c_end_transfer(bus); |
| return len; |
| } |
| |
| int smbus_write_block(I2CBus *bus, uint8_t addr, uint8_t command, uint8_t *data, |
| int len) |
| { |
| int i; |
| |
| if (len > 32) |
| len = 32; |
| |
| if (i2c_start_transfer(bus, addr, 0)) { |
| return -1; |
| } |
| i2c_send(bus, command); |
| i2c_send(bus, len); |
| for (i = 0; i < len; i++) { |
| i2c_send(bus, data[i]); |
| } |
| i2c_end_transfer(bus); |
| return 0; |
| } |
| |
| static void smbus_device_class_init(ObjectClass *klass, void *data) |
| { |
| I2CSlaveClass *sc = I2C_SLAVE_CLASS(klass); |
| |
| sc->init = smbus_device_init; |
| sc->event = smbus_i2c_event; |
| sc->recv = smbus_i2c_recv; |
| sc->send = smbus_i2c_send; |
| } |
| |
| static const TypeInfo smbus_device_type_info = { |
| .name = TYPE_SMBUS_DEVICE, |
| .parent = TYPE_I2C_SLAVE, |
| .instance_size = sizeof(SMBusDevice), |
| .abstract = true, |
| .class_size = sizeof(SMBusDeviceClass), |
| .class_init = smbus_device_class_init, |
| }; |
| |
| static void smbus_device_register_types(void) |
| { |
| type_register_static(&smbus_device_type_info); |
| } |
| |
| type_init(smbus_device_register_types) |
