hw/misc/tmp421.c - qemu - Git at Google

 /*
  * Texas Instruments TMP421 temperature sensor.
  *
  * Copyright (c) 2016 IBM Corporation.
  *
  * Largely inspired by :
  *
  * Texas Instruments TMP105 temperature sensor.
  *
  * Copyright (C) 2008 Nokia Corporation
  * Written by Andrzej Zaborowski <andrew@openedhand.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 or
  * (at your option) version 3 of the License.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License along
  * with this program; if not, see <http://www.gnu.org/licenses/>.
  */

 #include "qemu/osdep.h"
 #include "hw/hw.h"
 #include "hw/i2c/i2c.h"
 #include "qapi/error.h"
 #include "qapi/visitor.h"

 /* Manufacturer / Device ID's */
 #define TMP421_MANUFACTURER_ID          0x55
 #define TMP421_DEVICE_ID                0x21
 #define TMP422_DEVICE_ID                0x22
 #define TMP423_DEVICE_ID                0x23

 typedef struct DeviceInfo {
     int model;
     const char *name;
 } DeviceInfo;

 static const DeviceInfo devices[] = {
     { TMP421_DEVICE_ID, "tmp421" },
     { TMP422_DEVICE_ID, "tmp422" },
     { TMP423_DEVICE_ID, "tmp423" },
 };

 typedef struct TMP421State {
     /*< private >*/
     I2CSlave i2c;
     /*< public >*/

     int16_t temperature[4];

     uint8_t status;
     uint8_t config[2];
     uint8_t rate;

     uint8_t len;
     uint8_t buf[2];
     uint8_t pointer;

 } TMP421State;

 typedef struct TMP421Class {
     I2CSlaveClass parent_class;
     DeviceInfo *dev;
 } TMP421Class;

 #define TYPE_TMP421 "tmp421-generic"
 #define TMP421(obj) OBJECT_CHECK(TMP421State, (obj), TYPE_TMP421)

 #define TMP421_CLASS(klass) \
      OBJECT_CLASS_CHECK(TMP421Class, (klass), TYPE_TMP421)
 #define TMP421_GET_CLASS(obj) \
      OBJECT_GET_CLASS(TMP421Class, (obj), TYPE_TMP421)

 /* the TMP421 registers */
 #define TMP421_STATUS_REG               0x08
 #define    TMP421_STATUS_BUSY             (1 << 7)
 #define TMP421_CONFIG_REG_1             0x09
 #define    TMP421_CONFIG_RANGE            (1 << 2)
 #define    TMP421_CONFIG_SHUTDOWN         (1 << 6)
 #define TMP421_CONFIG_REG_2             0x0A
 #define    TMP421_CONFIG_RC               (1 << 2)
 #define    TMP421_CONFIG_LEN              (1 << 3)
 #define    TMP421_CONFIG_REN              (1 << 4)
 #define    TMP421_CONFIG_REN2             (1 << 5)
 #define    TMP421_CONFIG_REN3             (1 << 6)

 #define TMP421_CONVERSION_RATE_REG      0x0B
 #define TMP421_ONE_SHOT                 0x0F

 #define TMP421_RESET                    0xFC
 #define TMP421_MANUFACTURER_ID_REG      0xFE
 #define TMP421_DEVICE_ID_REG            0xFF

 #define TMP421_TEMP_MSB0                0x00
 #define TMP421_TEMP_MSB1                0x01
 #define TMP421_TEMP_MSB2                0x02
 #define TMP421_TEMP_MSB3                0x03
 #define TMP421_TEMP_LSB0                0x10
 #define TMP421_TEMP_LSB1                0x11
 #define TMP421_TEMP_LSB2                0x12
 #define TMP421_TEMP_LSB3                0x13

 static const int32_t mins[2] = { -40000, -55000 };
 static const int32_t maxs[2] = { 127000, 150000 };

 static void tmp421_get_temperature(Object *obj, Visitor *v, const char *name,
                                    void *opaque, Error **errp)
 {
     TMP421State *s = TMP421(obj);
     bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE);
     int offset = ext_range * 64 * 256;
     int64_t value;
     int tempid;

     if (sscanf(name, "temperature%d", &tempid) != 1) {
         error_setg(errp, "error reading %s: %m", name);
         return;
     }

     if (tempid >= 4 || tempid < 0) {
         error_setg(errp, "error reading %s", name);
         return;
     }

     value = ((s->temperature[tempid] - offset) * 1000 + 128) / 256;

     visit_type_int(v, name, &value, errp);
 }

 /* Units are 0.001 centigrades relative to 0 C.  s->temperature is 8.8
  * fixed point, so units are 1/256 centigrades.  A simple ratio will do.
  */
 static void tmp421_set_temperature(Object *obj, Visitor *v, const char *name,
                                    void *opaque, Error **errp)
 {
     TMP421State *s = TMP421(obj);
     Error *local_err = NULL;
     int64_t temp;
     bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE);
     int offset = ext_range * 64 * 256;
     int tempid;

     visit_type_int(v, name, &temp, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         return;
     }

     if (temp >= maxs[ext_range] || temp < mins[ext_range]) {
         error_setg(errp, "value %" PRId64 ".%03" PRIu64 " °C is out of range",
                    temp / 1000, temp % 1000);
         return;
     }

     if (sscanf(name, "temperature%d", &tempid) != 1) {
         error_setg(errp, "error reading %s: %m", name);
         return;
     }

     if (tempid >= 4 || tempid < 0) {
         error_setg(errp, "error reading %s", name);
         return;
     }

     s->temperature[tempid] = (int16_t) ((temp * 256 - 128) / 1000) + offset;
 }

 static void tmp421_read(TMP421State *s)
 {
     TMP421Class *sc = TMP421_GET_CLASS(s);

     s->len = 0;

     switch (s->pointer) {
     case TMP421_MANUFACTURER_ID_REG:
         s->buf[s->len++] = TMP421_MANUFACTURER_ID;
         break;
     case TMP421_DEVICE_ID_REG:
         s->buf[s->len++] = sc->dev->model;
         break;
     case TMP421_CONFIG_REG_1:
         s->buf[s->len++] = s->config[0];
         break;
     case TMP421_CONFIG_REG_2:
         s->buf[s->len++] = s->config[1];
         break;
     case TMP421_CONVERSION_RATE_REG:
         s->buf[s->len++] = s->rate;
         break;
     case TMP421_STATUS_REG:
         s->buf[s->len++] = s->status;
         break;

         /* FIXME: check for channel enablement in config registers */
     case TMP421_TEMP_MSB0:
         s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 8);
         s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0;
         break;
     case TMP421_TEMP_MSB1:
         s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 8);
         s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0;
         break;
     case TMP421_TEMP_MSB2:
         s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 8);
         s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0;
         break;
     case TMP421_TEMP_MSB3:
         s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 8);
         s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0;
         break;
     case TMP421_TEMP_LSB0:
         s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0;
         break;
     case TMP421_TEMP_LSB1:
         s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0;
         break;
     case TMP421_TEMP_LSB2:
         s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0;
         break;
     case TMP421_TEMP_LSB3:
         s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0;
         break;
     }
 }

 static void tmp421_reset(I2CSlave *i2c);

 static void tmp421_write(TMP421State *s)
 {
     switch (s->pointer) {
     case TMP421_CONVERSION_RATE_REG:
         s->rate = s->buf[0];
         break;
     case TMP421_CONFIG_REG_1:
         s->config[0] = s->buf[0];
         break;
     case TMP421_CONFIG_REG_2:
         s->config[1] = s->buf[0];
         break;
     case TMP421_RESET:
         tmp421_reset(I2C_SLAVE(s));
         break;
     }
 }

 static int tmp421_rx(I2CSlave *i2c)
 {
     TMP421State *s = TMP421(i2c);

     if (s->len < 2) {
         return s->buf[s->len++];
     } else {
         return 0xff;
     }
 }

 static int tmp421_tx(I2CSlave *i2c, uint8_t data)
 {
     TMP421State *s = TMP421(i2c);

     if (s->len == 0) {
         /* first byte is the register pointer for a read or write
          * operation */
         s->pointer = data;
         s->len++;
     } else if (s->len == 1) {
         /* second byte is the data to write. The device only supports
          * one byte writes */
         s->buf[0] = data;
         tmp421_write(s);
     }

     return 0;
 }

 static int tmp421_event(I2CSlave *i2c, enum i2c_event event)
 {
     TMP421State *s = TMP421(i2c);

     if (event == I2C_START_RECV) {
         tmp421_read(s);
     }

     s->len = 0;
     return 0;
 }

 static const VMStateDescription vmstate_tmp421 = {
     .name = "TMP421",
     .version_id = 0,
     .minimum_version_id = 0,
     .fields = (VMStateField[]) {
         VMSTATE_UINT8(len, TMP421State),
         VMSTATE_UINT8_ARRAY(buf, TMP421State, 2),
         VMSTATE_UINT8(pointer, TMP421State),
         VMSTATE_UINT8_ARRAY(config, TMP421State, 2),
         VMSTATE_UINT8(status, TMP421State),
         VMSTATE_UINT8(rate, TMP421State),
         VMSTATE_INT16_ARRAY(temperature, TMP421State, 4),
         VMSTATE_I2C_SLAVE(i2c, TMP421State),
         VMSTATE_END_OF_LIST()
     }
 };

 static void tmp421_reset(I2CSlave *i2c)
 {
     TMP421State *s = TMP421(i2c);
     TMP421Class *sc = TMP421_GET_CLASS(s);

     memset(s->temperature, 0, sizeof(s->temperature));
     s->pointer = 0;

     s->config[0] = 0; /* TMP421_CONFIG_RANGE */

      /* resistance correction and channel enablement */
     switch (sc->dev->model) {
     case TMP421_DEVICE_ID:
         s->config[1] = 0x1c;
         break;
     case TMP422_DEVICE_ID:
         s->config[1] = 0x3c;
         break;
     case TMP423_DEVICE_ID:
         s->config[1] = 0x7c;
         break;
     }

     s->rate = 0x7;       /* 8Hz */
     s->status = 0;
 }

 static int tmp421_init(I2CSlave *i2c)
 {
     TMP421State *s = TMP421(i2c);

     tmp421_reset(&s->i2c);

     return 0;
 }

 static void tmp421_initfn(Object *obj)
 {
     object_property_add(obj, "temperature0", "int",
                         tmp421_get_temperature,
                         tmp421_set_temperature, NULL, NULL, NULL);
     object_property_add(obj, "temperature1", "int",
                         tmp421_get_temperature,
                         tmp421_set_temperature, NULL, NULL, NULL);
     object_property_add(obj, "temperature2", "int",
                         tmp421_get_temperature,
                         tmp421_set_temperature, NULL, NULL, NULL);
     object_property_add(obj, "temperature3", "int",
                         tmp421_get_temperature,
                         tmp421_set_temperature, NULL, NULL, NULL);
 }

 static void tmp421_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
     I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
     TMP421Class *sc = TMP421_CLASS(klass);

     k->init = tmp421_init;
     k->event = tmp421_event;
     k->recv = tmp421_rx;
     k->send = tmp421_tx;
     dc->vmsd = &vmstate_tmp421;
     sc->dev = (DeviceInfo *) data;
 }

 static const TypeInfo tmp421_info = {
     .name          = TYPE_TMP421,
     .parent        = TYPE_I2C_SLAVE,
     .instance_size = sizeof(TMP421State),
     .class_size    = sizeof(TMP421Class),
     .instance_init = tmp421_initfn,
     .abstract      = true,
 };

 static void tmp421_register_types(void)
 {
     int i;

     type_register_static(&tmp421_info);
     for (i = 0; i < ARRAY_SIZE(devices); ++i) {
         TypeInfo ti = {
             .name       = devices[i].name,
             .parent     = TYPE_TMP421,
             .class_init = tmp421_class_init,
             .class_data = (void *) &devices[i],
         };
         type_register(&ti);
     }
 }

 type_init(tmp421_register_types)
	/*
	* Texas Instruments TMP421 temperature sensor.
	*
	* Copyright (c) 2016 IBM Corporation.
	*
	* Largely inspired by :
	*
	* Texas Instruments TMP105 temperature sensor.
	*
	* Copyright (C) 2008 Nokia Corporation
	* Written by Andrzej Zaborowski <andrew@openedhand.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation; either version 2 or
	* (at your option) version 3 of the License.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, see <http://www.gnu.org/licenses/>.
	*/

	#include "qemu/osdep.h"
	#include "hw/hw.h"
	#include "hw/i2c/i2c.h"
	#include "qapi/error.h"
	#include "qapi/visitor.h"

	/* Manufacturer / Device ID's */
	#define TMP421_MANUFACTURER_ID 0x55
	#define TMP421_DEVICE_ID 0x21
	#define TMP422_DEVICE_ID 0x22
	#define TMP423_DEVICE_ID 0x23

	typedef struct DeviceInfo {
	int model;
	const char *name;
	} DeviceInfo;

	static const DeviceInfo devices[] = {
	{ TMP421_DEVICE_ID, "tmp421" },
	{ TMP422_DEVICE_ID, "tmp422" },
	{ TMP423_DEVICE_ID, "tmp423" },
	};

	typedef struct TMP421State {
	/< private >/
	I2CSlave i2c;
	/< public >/

	int16_t temperature[4];

	uint8_t status;
	uint8_t config[2];
	uint8_t rate;

	uint8_t len;
	uint8_t buf[2];
	uint8_t pointer;

	} TMP421State;

	typedef struct TMP421Class {
	I2CSlaveClass parent_class;
	DeviceInfo *dev;
	} TMP421Class;

	#define TYPE_TMP421 "tmp421-generic"
	#define TMP421(obj) OBJECT_CHECK(TMP421State, (obj), TYPE_TMP421)

	#define TMP421_CLASS(klass) \
	OBJECT_CLASS_CHECK(TMP421Class, (klass), TYPE_TMP421)
	#define TMP421_GET_CLASS(obj) \
	OBJECT_GET_CLASS(TMP421Class, (obj), TYPE_TMP421)

	/* the TMP421 registers */
	#define TMP421_STATUS_REG 0x08
	#define TMP421_STATUS_BUSY (1 << 7)
	#define TMP421_CONFIG_REG_1 0x09
	#define TMP421_CONFIG_RANGE (1 << 2)
	#define TMP421_CONFIG_SHUTDOWN (1 << 6)
	#define TMP421_CONFIG_REG_2 0x0A
	#define TMP421_CONFIG_RC (1 << 2)
	#define TMP421_CONFIG_LEN (1 << 3)
	#define TMP421_CONFIG_REN (1 << 4)
	#define TMP421_CONFIG_REN2 (1 << 5)
	#define TMP421_CONFIG_REN3 (1 << 6)

	#define TMP421_CONVERSION_RATE_REG 0x0B
	#define TMP421_ONE_SHOT 0x0F

	#define TMP421_RESET 0xFC
	#define TMP421_MANUFACTURER_ID_REG 0xFE
	#define TMP421_DEVICE_ID_REG 0xFF

	#define TMP421_TEMP_MSB0 0x00
	#define TMP421_TEMP_MSB1 0x01
	#define TMP421_TEMP_MSB2 0x02
	#define TMP421_TEMP_MSB3 0x03
	#define TMP421_TEMP_LSB0 0x10
	#define TMP421_TEMP_LSB1 0x11
	#define TMP421_TEMP_LSB2 0x12
	#define TMP421_TEMP_LSB3 0x13

	static const int32_t mins[2] = { -40000, -55000 };
	static const int32_t maxs[2] = { 127000, 150000 };

	static void tmp421_get_temperature(Object obj, Visitor v, const char *name,
	void opaque, Error *errp)
	{
	TMP421State *s = TMP421(obj);
	bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE);
	int offset = ext_range * 64 * 256;
	int64_t value;
	int tempid;

	if (sscanf(name, "temperature%d", &tempid) != 1) {
	error_setg(errp, "error reading %s: %m", name);
	return;
	}

	if (tempid >= 4 \|\| tempid < 0) {
	error_setg(errp, "error reading %s", name);
	return;
	}

	value = ((s->temperature[tempid] - offset) * 1000 + 128) / 256;

	visit_type_int(v, name, &value, errp);
	}

	/* Units are 0.001 centigrades relative to 0 C. s->temperature is 8.8
	* fixed point, so units are 1/256 centigrades. A simple ratio will do.
	*/
	static void tmp421_set_temperature(Object obj, Visitor v, const char *name,
	void opaque, Error *errp)
	{
	TMP421State *s = TMP421(obj);
	Error *local_err = NULL;
	int64_t temp;
	bool ext_range = (s->config[0] & TMP421_CONFIG_RANGE);
	int offset = ext_range * 64 * 256;
	int tempid;

	visit_type_int(v, name, &temp, &local_err);
	if (local_err) {
	error_propagate(errp, local_err);
	return;
	}

	if (temp >= maxs[ext_range] \|\| temp < mins[ext_range]) {
	error_setg(errp, "value %" PRId64 ".%03" PRIu64 " °C is out of range",
	temp / 1000, temp % 1000);
	return;
	}

	if (sscanf(name, "temperature%d", &tempid) != 1) {
	error_setg(errp, "error reading %s: %m", name);
	return;
	}

	if (tempid >= 4 \|\| tempid < 0) {
	error_setg(errp, "error reading %s", name);
	return;
	}

	s->temperature[tempid] = (int16_t) ((temp * 256 - 128) / 1000) + offset;
	}

	static void tmp421_read(TMP421State *s)
	{
	TMP421Class *sc = TMP421_GET_CLASS(s);

	s->len = 0;

	switch (s->pointer) {
	case TMP421_MANUFACTURER_ID_REG:
	s->buf[s->len++] = TMP421_MANUFACTURER_ID;
	break;
	case TMP421_DEVICE_ID_REG:
	s->buf[s->len++] = sc->dev->model;
	break;
	case TMP421_CONFIG_REG_1:
	s->buf[s->len++] = s->config[0];
	break;
	case TMP421_CONFIG_REG_2:
	s->buf[s->len++] = s->config[1];
	break;
	case TMP421_CONVERSION_RATE_REG:
	s->buf[s->len++] = s->rate;
	break;
	case TMP421_STATUS_REG:
	s->buf[s->len++] = s->status;
	break;

	/* FIXME: check for channel enablement in config registers */
	case TMP421_TEMP_MSB0:
	s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 8);
	s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0;
	break;
	case TMP421_TEMP_MSB1:
	s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 8);
	s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0;
	break;
	case TMP421_TEMP_MSB2:
	s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 8);
	s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0;
	break;
	case TMP421_TEMP_MSB3:
	s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 8);
	s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0;
	break;
	case TMP421_TEMP_LSB0:
	s->buf[s->len++] = (((uint16_t) s->temperature[0]) >> 0) & 0xf0;
	break;
	case TMP421_TEMP_LSB1:
	s->buf[s->len++] = (((uint16_t) s->temperature[1]) >> 0) & 0xf0;
	break;
	case TMP421_TEMP_LSB2:
	s->buf[s->len++] = (((uint16_t) s->temperature[2]) >> 0) & 0xf0;
	break;
	case TMP421_TEMP_LSB3:
	s->buf[s->len++] = (((uint16_t) s->temperature[3]) >> 0) & 0xf0;
	break;
	}
	}

	static void tmp421_reset(I2CSlave *i2c);

	static void tmp421_write(TMP421State *s)
	{
	switch (s->pointer) {
	case TMP421_CONVERSION_RATE_REG:
	s->rate = s->buf[0];
	break;
	case TMP421_CONFIG_REG_1:
	s->config[0] = s->buf[0];
	break;
	case TMP421_CONFIG_REG_2:
	s->config[1] = s->buf[0];
	break;
	case TMP421_RESET:
	tmp421_reset(I2C_SLAVE(s));
	break;
	}
	}

	static int tmp421_rx(I2CSlave *i2c)
	{
	TMP421State *s = TMP421(i2c);

	if (s->len < 2) {
	return s->buf[s->len++];
	} else {
	return 0xff;
	}
	}

	static int tmp421_tx(I2CSlave *i2c, uint8_t data)
	{
	TMP421State *s = TMP421(i2c);

	if (s->len == 0) {
	/* first byte is the register pointer for a read or write
	* operation */
	s->pointer = data;
	s->len++;
	} else if (s->len == 1) {
	/* second byte is the data to write. The device only supports
	* one byte writes */
	s->buf[0] = data;
	tmp421_write(s);
	}

	return 0;
	}

	static int tmp421_event(I2CSlave *i2c, enum i2c_event event)
	{
	TMP421State *s = TMP421(i2c);

	if (event == I2C_START_RECV) {
	tmp421_read(s);
	}

	s->len = 0;
	return 0;
	}

	static const VMStateDescription vmstate_tmp421 = {
	.name = "TMP421",
	.version_id = 0,
	.minimum_version_id = 0,
	.fields = (VMStateField[]) {
	VMSTATE_UINT8(len, TMP421State),
	VMSTATE_UINT8_ARRAY(buf, TMP421State, 2),
	VMSTATE_UINT8(pointer, TMP421State),
	VMSTATE_UINT8_ARRAY(config, TMP421State, 2),
	VMSTATE_UINT8(status, TMP421State),
	VMSTATE_UINT8(rate, TMP421State),
	VMSTATE_INT16_ARRAY(temperature, TMP421State, 4),
	VMSTATE_I2C_SLAVE(i2c, TMP421State),
	VMSTATE_END_OF_LIST()
	}
	};

	static void tmp421_reset(I2CSlave *i2c)
	{
	TMP421State *s = TMP421(i2c);
	TMP421Class *sc = TMP421_GET_CLASS(s);

	memset(s->temperature, 0, sizeof(s->temperature));
	s->pointer = 0;

	s->config[0] = 0; /* TMP421_CONFIG_RANGE */

	/* resistance correction and channel enablement */
	switch (sc->dev->model) {
	case TMP421_DEVICE_ID:
	s->config[1] = 0x1c;
	break;
	case TMP422_DEVICE_ID:
	s->config[1] = 0x3c;
	break;
	case TMP423_DEVICE_ID:
	s->config[1] = 0x7c;
	break;
	}

	s->rate = 0x7; /* 8Hz */
	s->status = 0;
	}

	static int tmp421_init(I2CSlave *i2c)
	{
	TMP421State *s = TMP421(i2c);

	tmp421_reset(&s->i2c);

	return 0;
	}

	static void tmp421_initfn(Object *obj)
	{
	object_property_add(obj, "temperature0", "int",
	tmp421_get_temperature,
	tmp421_set_temperature, NULL, NULL, NULL);
	object_property_add(obj, "temperature1", "int",
	tmp421_get_temperature,
	tmp421_set_temperature, NULL, NULL, NULL);
	object_property_add(obj, "temperature2", "int",
	tmp421_get_temperature,
	tmp421_set_temperature, NULL, NULL, NULL);
	object_property_add(obj, "temperature3", "int",
	tmp421_get_temperature,
	tmp421_set_temperature, NULL, NULL, NULL);
	}

	static void tmp421_class_init(ObjectClass klass, void data)
	{
	DeviceClass *dc = DEVICE_CLASS(klass);
	I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
	TMP421Class *sc = TMP421_CLASS(klass);

	k->init = tmp421_init;
	k->event = tmp421_event;
	k->recv = tmp421_rx;
	k->send = tmp421_tx;
	dc->vmsd = &vmstate_tmp421;
	sc->dev = (DeviceInfo *) data;
	}

	static const TypeInfo tmp421_info = {
	.name = TYPE_TMP421,
	.parent = TYPE_I2C_SLAVE,
	.instance_size = sizeof(TMP421State),
	.class_size = sizeof(TMP421Class),
	.instance_init = tmp421_initfn,
	.abstract = true,
	};

	static void tmp421_register_types(void)
	{
	int i;

	type_register_static(&tmp421_info);
	for (i = 0; i < ARRAY_SIZE(devices); ++i) {
	TypeInfo ti = {
	.name = devices[i].name,
	.parent = TYPE_TMP421,
	.class_init = tmp421_class_init,
	.class_data = (void *) &devices[i],
	};
	type_register(&ti);
	}
	}

	type_init(tmp421_register_types)