--- qemu/hw/i2c.c 2018/04/24 16:48:18 1.1 +++ qemu/hw/i2c.c 2018/04/24 17:23:17 1.1.1.3 @@ -7,38 +7,59 @@ * This code is licenced under the LGPL. */ -#include "hw.h" #include "i2c.h" struct i2c_bus { + BusState qbus; i2c_slave *current_dev; i2c_slave *dev; + int saved_address; }; -/* Create a new I2C bus. */ -i2c_bus *i2c_init_bus(void) +static struct BusInfo i2c_bus_info = { + .name = "I2C", + .size = sizeof(i2c_bus), + .props = (Property[]) { + { + .name = "address", + .info = &qdev_prop_uint32, + .offset = offsetof(struct i2c_slave, address), + }, + {/* end of list */} + } +}; + +static void i2c_bus_save(QEMUFile *f, void *opaque) { - i2c_bus *bus; + i2c_bus *bus = (i2c_bus *)opaque; - bus = (i2c_bus *)qemu_mallocz(sizeof(i2c_bus)); - return bus; + qemu_put_byte(f, bus->current_dev ? bus->current_dev->address : -1); } -/* Create a new slave device. */ -i2c_slave *i2c_slave_init(i2c_bus *bus, int address, int size) +static int i2c_bus_load(QEMUFile *f, void *opaque, int version_id) { - i2c_slave *dev; + i2c_bus *bus = (i2c_bus *)opaque; - if (size < sizeof(i2c_slave)) - hw_error("I2C struct too small"); + if (version_id != 1) + return -EINVAL; - dev = (i2c_slave *)qemu_mallocz(size); - dev->address = address; - dev->next = bus->dev; - bus->dev = dev; + /* The bus is loaded before attached devices, so load and save the + current device id. Devices will check themselves as loaded. */ + bus->saved_address = (int8_t) qemu_get_byte(f); + bus->current_dev = NULL; - return dev; + return 0; +} + +/* Create a new I2C bus. */ +i2c_bus *i2c_init_bus(DeviceState *parent, const char *name) +{ + i2c_bus *bus; + + bus = FROM_QBUS(i2c_bus, qbus_create(&i2c_bus_info, parent, name)); + register_savevm("i2c_bus", -1, 1, i2c_bus_save, i2c_bus_load, bus); + return bus; } void i2c_set_slave_address(i2c_slave *dev, int address) @@ -56,20 +77,22 @@ int i2c_bus_busy(i2c_bus *bus) /* TODO: Make this handle multiple masters. */ int i2c_start_transfer(i2c_bus *bus, int address, int recv) { - i2c_slave *dev; + DeviceState *qdev; + i2c_slave *slave = NULL; - for (dev = bus->dev; dev; dev = dev->next) { - if (dev->address == address) + LIST_FOREACH(qdev, &bus->qbus.children, sibling) { + slave = I2C_SLAVE_FROM_QDEV(qdev); + if (slave->address == address) break; } - if (!dev) + if (!slave) return 1; /* If the bus is already busy, assume this is a repeated start condition. */ - bus->current_dev = dev; - dev->event(dev, recv ? I2C_START_RECV : I2C_START_SEND); + bus->current_dev = slave; + slave->info->event(slave, recv ? I2C_START_RECV : I2C_START_SEND); return 0; } @@ -80,7 +103,7 @@ void i2c_end_transfer(i2c_bus *bus) if (!dev) return; - dev->event(dev, I2C_FINISH); + dev->info->event(dev, I2C_FINISH); bus->current_dev = NULL; } @@ -92,7 +115,7 @@ int i2c_send(i2c_bus *bus, uint8_t data) if (!dev) return -1; - return dev->send(dev, data); + return dev->info->send(dev, data); } int i2c_recv(i2c_bus *bus) @@ -102,7 +125,7 @@ int i2c_recv(i2c_bus *bus) if (!dev) return -1; - return dev->recv(dev); + return dev->info->recv(dev); } void i2c_nack(i2c_bus *bus) @@ -112,37 +135,48 @@ void i2c_nack(i2c_bus *bus) if (!dev) return; - dev->event(dev, I2C_NACK); + dev->info->event(dev, I2C_NACK); } -void i2c_bus_save(QEMUFile *f, i2c_bus *bus) +void i2c_slave_save(QEMUFile *f, i2c_slave *dev) { - qemu_put_byte(f, bus->current_dev ? bus->current_dev->address : 0x00); + qemu_put_byte(f, dev->address); } -void i2c_bus_load(QEMUFile *f, i2c_bus *bus) +void i2c_slave_load(QEMUFile *f, i2c_slave *dev) { - i2c_slave *dev; - uint8_t address = qemu_get_byte(f); + i2c_bus *bus; + bus = FROM_QBUS(i2c_bus, qdev_get_parent_bus(&dev->qdev)); + dev->address = qemu_get_byte(f); + if (bus->saved_address == dev->address) { + bus->current_dev = dev; + } +} - if (address) { - for (dev = bus->dev; dev; dev = dev->next) - if (dev->address == address) { - bus->current_dev = dev; - return; - } +static void i2c_slave_qdev_init(DeviceState *dev, DeviceInfo *base) +{ + I2CSlaveInfo *info = container_of(base, I2CSlaveInfo, qdev); + i2c_slave *s = I2C_SLAVE_FROM_QDEV(dev); - fprintf(stderr, "%s: I2C slave with address %02x disappeared\n", - __FUNCTION__, address); - } + s->info = info; + + info->init(s); } -void i2c_slave_save(QEMUFile *f, i2c_slave *dev) +void i2c_register_slave(I2CSlaveInfo *info) { - qemu_put_byte(f, dev->address); + assert(info->qdev.size >= sizeof(i2c_slave)); + info->qdev.init = i2c_slave_qdev_init; + info->qdev.bus_info = &i2c_bus_info; + qdev_register(&info->qdev); } -void i2c_slave_load(QEMUFile *f, i2c_slave *dev) +DeviceState *i2c_create_slave(i2c_bus *bus, const char *name, int addr) { - dev->address = qemu_get_byte(f); + DeviceState *dev; + + dev = qdev_create(&bus->qbus, name); + qdev_prop_set_uint32(dev, "address", addr); + qdev_init(dev); + return dev; }