hw/misc/tmp105.c - qemu - Git at Google

 /*
  * 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/i2c/i2c.h"
 #include "hw/irq.h"
 #include "migration/vmstate.h"
 #include "tmp105.h"
 #include "qapi/error.h"
 #include "qapi/visitor.h"
 #include "qemu/module.h"

 static void tmp105_interrupt_update(TMP105State *s)
 {
     qemu_set_irq(s->pin, s->alarm ^ ((~s->config >> 2) & 1));	/* POL */
 }

 static void tmp105_alarm_update(TMP105State *s)
 {
     if ((s->config >> 0) & 1) {					/* SD */
         if ((s->config >> 7) & 1)				/* OS */
             s->config &= ~(1 << 7);				/* OS */
         else
             return;
     }

     if (s->config >> 1 & 1) {
         /*
          * TM == 1 : Interrupt mode. We signal Alert when the
          * temperature rises above T_high, and expect the guest to clear
          * it (eg by reading a device register).
          */
         if (s->detect_falling) {
             if (s->temperature < s->limit[0]) {
                 s->alarm = 1;
                 s->detect_falling = false;
             }
         } else {
             if (s->temperature >= s->limit[1]) {
                 s->alarm = 1;
                 s->detect_falling = true;
             }
         }
     } else {
         /*
          * TM == 0 : Comparator mode. We signal Alert when the temperature
          * rises above T_high, and stop signalling it when the temperature
          * falls below T_low.
          */
         if (s->detect_falling) {
             if (s->temperature < s->limit[0]) {
                 s->alarm = 0;
                 s->detect_falling = false;
             }
         } else {
             if (s->temperature >= s->limit[1]) {
                 s->alarm = 1;
                 s->detect_falling = true;
             }
         }
     }

     tmp105_interrupt_update(s);
 }

 static void tmp105_get_temperature(Object *obj, Visitor *v, const char *name,
                                    void *opaque, Error **errp)
 {
     TMP105State *s = TMP105(obj);
     int64_t value = s->temperature * 1000 / 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 tmp105_set_temperature(Object *obj, Visitor *v, const char *name,
                                    void *opaque, Error **errp)
 {
     TMP105State *s = TMP105(obj);
     int64_t temp;

     if (!visit_type_int(v, name, &temp, errp)) {
         return;
     }
     if (temp >= 128000 || temp < -128000) {
         error_setg(errp, "value %" PRId64 ".%03" PRIu64 " C is out of range",
                    temp / 1000, temp % 1000);
         return;
     }

     s->temperature = (int16_t) (temp * 256 / 1000);

     tmp105_alarm_update(s);
 }

 static const int tmp105_faultq[4] = { 1, 2, 4, 6 };

 static void tmp105_read(TMP105State *s)
 {
     s->len = 0;

     if ((s->config >> 1) & 1) {					/* TM */
         s->alarm = 0;
         tmp105_interrupt_update(s);
     }

     switch (s->pointer & 3) {
     case TMP105_REG_TEMPERATURE:
         s->buf[s->len ++] = (((uint16_t) s->temperature) >> 8);
         s->buf[s->len ++] = (((uint16_t) s->temperature) >> 0) &
                 (0xf0 << ((~s->config >> 5) & 3));		/* R */
         break;

     case TMP105_REG_CONFIG:
         s->buf[s->len ++] = s->config;
         break;

     case TMP105_REG_T_LOW:
         s->buf[s->len ++] = ((uint16_t) s->limit[0]) >> 8;
         s->buf[s->len ++] = ((uint16_t) s->limit[0]) >> 0;
         break;

     case TMP105_REG_T_HIGH:
         s->buf[s->len ++] = ((uint16_t) s->limit[1]) >> 8;
         s->buf[s->len ++] = ((uint16_t) s->limit[1]) >> 0;
         break;
     }
 }

 static void tmp105_write(TMP105State *s)
 {
     switch (s->pointer & 3) {
     case TMP105_REG_TEMPERATURE:
         break;

     case TMP105_REG_CONFIG:
         if (s->buf[0] & ~s->config & (1 << 0))			/* SD */
             printf("%s: TMP105 shutdown\n", __func__);
         s->config = s->buf[0];
         s->faults = tmp105_faultq[(s->config >> 3) & 3];	/* F */
         tmp105_alarm_update(s);
         break;

     case TMP105_REG_T_LOW:
     case TMP105_REG_T_HIGH:
         if (s->len >= 3)
             s->limit[s->pointer & 1] = (int16_t)
                     ((((uint16_t) s->buf[0]) << 8) | s->buf[1]);
         tmp105_alarm_update(s);
         break;
     }
 }

 static uint8_t tmp105_rx(I2CSlave *i2c)
 {
     TMP105State *s = TMP105(i2c);

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

 static int tmp105_tx(I2CSlave *i2c, uint8_t data)
 {
     TMP105State *s = TMP105(i2c);

     if (s->len == 0) {
         s->pointer = data;
         s->len++;
     } else {
         if (s->len <= 2) {
             s->buf[s->len - 1] = data;
         }
         s->len++;
         tmp105_write(s);
     }

     return 0;
 }

 static int tmp105_event(I2CSlave *i2c, enum i2c_event event)
 {
     TMP105State *s = TMP105(i2c);

     if (event == I2C_START_RECV) {
         tmp105_read(s);
     }

     s->len = 0;
     return 0;
 }

 static int tmp105_post_load(void *opaque, int version_id)
 {
     TMP105State *s = opaque;

     s->faults = tmp105_faultq[(s->config >> 3) & 3];		/* F */

     tmp105_interrupt_update(s);
     return 0;
 }

 static bool detect_falling_needed(void *opaque)
 {
     TMP105State *s = opaque;

     /*
      * We only need to migrate the detect_falling bool if it's set;
      * for migration from older machines we assume that it is false
      * (ie temperature is not out of range).
      */
     return s->detect_falling;
 }

 static const VMStateDescription vmstate_tmp105_detect_falling = {
     .name = "TMP105/detect-falling",
     .version_id = 1,
     .minimum_version_id = 1,
     .needed = detect_falling_needed,
     .fields = (VMStateField[]) {
         VMSTATE_BOOL(detect_falling, TMP105State),
         VMSTATE_END_OF_LIST()
     }
 };

 static const VMStateDescription vmstate_tmp105 = {
     .name = "TMP105",
     .version_id = 0,
     .minimum_version_id = 0,
     .post_load = tmp105_post_load,
     .fields = (VMStateField[]) {
         VMSTATE_UINT8(len, TMP105State),
         VMSTATE_UINT8_ARRAY(buf, TMP105State, 2),
         VMSTATE_UINT8(pointer, TMP105State),
         VMSTATE_UINT8(config, TMP105State),
         VMSTATE_INT16(temperature, TMP105State),
         VMSTATE_INT16_ARRAY(limit, TMP105State, 2),
         VMSTATE_UINT8(alarm, TMP105State),
         VMSTATE_I2C_SLAVE(i2c, TMP105State),
         VMSTATE_END_OF_LIST()
     },
     .subsections = (const VMStateDescription*[]) {
         &vmstate_tmp105_detect_falling,
         NULL
     }
 };

 static void tmp105_reset(I2CSlave *i2c)
 {
     TMP105State *s = TMP105(i2c);

     s->temperature = 0;
     s->pointer = 0;
     s->config = 0;
     s->faults = tmp105_faultq[(s->config >> 3) & 3];
     s->alarm = 0;
     s->detect_falling = false;

     s->limit[0] = 0x4b00; /* T_LOW, 75 degrees C */
     s->limit[1] = 0x5000; /* T_HIGH, 80 degrees C */

     tmp105_interrupt_update(s);
 }

 static void tmp105_realize(DeviceState *dev, Error **errp)
 {
     I2CSlave *i2c = I2C_SLAVE(dev);
     TMP105State *s = TMP105(i2c);

     qdev_init_gpio_out(&i2c->qdev, &s->pin, 1);

     tmp105_reset(&s->i2c);
 }

 static void tmp105_initfn(Object *obj)
 {
     object_property_add(obj, "temperature", "int",
                         tmp105_get_temperature,
                         tmp105_set_temperature, NULL, NULL);
 }

 static void tmp105_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
     I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);

     dc->realize = tmp105_realize;
     k->event = tmp105_event;
     k->recv = tmp105_rx;
     k->send = tmp105_tx;
     dc->vmsd = &vmstate_tmp105;
 }

 static const TypeInfo tmp105_info = {
     .name          = TYPE_TMP105,
     .parent        = TYPE_I2C_SLAVE,
     .instance_size = sizeof(TMP105State),
     .instance_init = tmp105_initfn,
     .class_init    = tmp105_class_init,
 };

 static void tmp105_register_types(void)
 {
     type_register_static(&tmp105_info);
 }

 type_init(tmp105_register_types)
	/*
	* 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/i2c/i2c.h"
	#include "hw/irq.h"
	#include "migration/vmstate.h"
	#include "tmp105.h"
	#include "qapi/error.h"
	#include "qapi/visitor.h"
	#include "qemu/module.h"

	static void tmp105_interrupt_update(TMP105State *s)
	{
	qemu_set_irq(s->pin, s->alarm ^ ((~s->config >> 2) & 1)); /* POL */
	}

	static void tmp105_alarm_update(TMP105State *s)
	{
	if ((s->config >> 0) & 1) { /* SD */
	if ((s->config >> 7) & 1) /* OS */
	s->config &= ~(1 << 7); /* OS */
	else
	return;
	}

	if (s->config >> 1 & 1) {
	/*
	* TM == 1 : Interrupt mode. We signal Alert when the
	* temperature rises above T_high, and expect the guest to clear
	* it (eg by reading a device register).
	*/
	if (s->detect_falling) {
	if (s->temperature < s->limit[0]) {
	s->alarm = 1;
	s->detect_falling = false;
	}
	} else {
	if (s->temperature >= s->limit[1]) {
	s->alarm = 1;
	s->detect_falling = true;
	}
	}
	} else {
	/*
	* TM == 0 : Comparator mode. We signal Alert when the temperature
	* rises above T_high, and stop signalling it when the temperature
	* falls below T_low.
	*/
	if (s->detect_falling) {
	if (s->temperature < s->limit[0]) {
	s->alarm = 0;
	s->detect_falling = false;
	}
	} else {
	if (s->temperature >= s->limit[1]) {
	s->alarm = 1;
	s->detect_falling = true;
	}
	}
	}

	tmp105_interrupt_update(s);
	}

	static void tmp105_get_temperature(Object obj, Visitor v, const char *name,
	void opaque, Error *errp)
	{
	TMP105State *s = TMP105(obj);
	int64_t value = s->temperature * 1000 / 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 tmp105_set_temperature(Object obj, Visitor v, const char *name,
	void opaque, Error *errp)
	{
	TMP105State *s = TMP105(obj);
	int64_t temp;

	if (!visit_type_int(v, name, &temp, errp)) {
	return;
	}
	if (temp >= 128000 \|\| temp < -128000) {
	error_setg(errp, "value %" PRId64 ".%03" PRIu64 " C is out of range",
	temp / 1000, temp % 1000);
	return;
	}

	s->temperature = (int16_t) (temp * 256 / 1000);

	tmp105_alarm_update(s);
	}

	static const int tmp105_faultq[4] = { 1, 2, 4, 6 };

	static void tmp105_read(TMP105State *s)
	{
	s->len = 0;

	if ((s->config >> 1) & 1) { /* TM */
	s->alarm = 0;
	tmp105_interrupt_update(s);
	}

	switch (s->pointer & 3) {
	case TMP105_REG_TEMPERATURE:
	s->buf[s->len ++] = (((uint16_t) s->temperature) >> 8);
	s->buf[s->len ++] = (((uint16_t) s->temperature) >> 0) &
	(0xf0 << ((~s->config >> 5) & 3)); /* R */
	break;

	case TMP105_REG_CONFIG:
	s->buf[s->len ++] = s->config;
	break;

	case TMP105_REG_T_LOW:
	s->buf[s->len ++] = ((uint16_t) s->limit[0]) >> 8;
	s->buf[s->len ++] = ((uint16_t) s->limit[0]) >> 0;
	break;

	case TMP105_REG_T_HIGH:
	s->buf[s->len ++] = ((uint16_t) s->limit[1]) >> 8;
	s->buf[s->len ++] = ((uint16_t) s->limit[1]) >> 0;
	break;
	}
	}

	static void tmp105_write(TMP105State *s)
	{
	switch (s->pointer & 3) {
	case TMP105_REG_TEMPERATURE:
	break;

	case TMP105_REG_CONFIG:
	if (s->buf[0] & ~s->config & (1 << 0)) /* SD */
	printf("%s: TMP105 shutdown\n", __func__);
	s->config = s->buf[0];
	s->faults = tmp105_faultq[(s->config >> 3) & 3]; /* F */
	tmp105_alarm_update(s);
	break;

	case TMP105_REG_T_LOW:
	case TMP105_REG_T_HIGH:
	if (s->len >= 3)
	s->limit[s->pointer & 1] = (int16_t)
	((((uint16_t) s->buf[0]) << 8) \| s->buf[1]);
	tmp105_alarm_update(s);
	break;
	}
	}

	static uint8_t tmp105_rx(I2CSlave *i2c)
	{
	TMP105State *s = TMP105(i2c);

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

	static int tmp105_tx(I2CSlave *i2c, uint8_t data)
	{
	TMP105State *s = TMP105(i2c);

	if (s->len == 0) {
	s->pointer = data;
	s->len++;
	} else {
	if (s->len <= 2) {
	s->buf[s->len - 1] = data;
	}
	s->len++;
	tmp105_write(s);
	}

	return 0;
	}

	static int tmp105_event(I2CSlave *i2c, enum i2c_event event)
	{
	TMP105State *s = TMP105(i2c);

	if (event == I2C_START_RECV) {
	tmp105_read(s);
	}

	s->len = 0;
	return 0;
	}

	static int tmp105_post_load(void *opaque, int version_id)
	{
	TMP105State *s = opaque;

	s->faults = tmp105_faultq[(s->config >> 3) & 3]; /* F */

	tmp105_interrupt_update(s);
	return 0;
	}

	static bool detect_falling_needed(void *opaque)
	{
	TMP105State *s = opaque;

	/*
	* We only need to migrate the detect_falling bool if it's set;
	* for migration from older machines we assume that it is false
	* (ie temperature is not out of range).
	*/
	return s->detect_falling;
	}

	static const VMStateDescription vmstate_tmp105_detect_falling = {
	.name = "TMP105/detect-falling",
	.version_id = 1,
	.minimum_version_id = 1,
	.needed = detect_falling_needed,
	.fields = (VMStateField[]) {
	VMSTATE_BOOL(detect_falling, TMP105State),
	VMSTATE_END_OF_LIST()
	}
	};

	static const VMStateDescription vmstate_tmp105 = {
	.name = "TMP105",
	.version_id = 0,
	.minimum_version_id = 0,
	.post_load = tmp105_post_load,
	.fields = (VMStateField[]) {
	VMSTATE_UINT8(len, TMP105State),
	VMSTATE_UINT8_ARRAY(buf, TMP105State, 2),
	VMSTATE_UINT8(pointer, TMP105State),
	VMSTATE_UINT8(config, TMP105State),
	VMSTATE_INT16(temperature, TMP105State),
	VMSTATE_INT16_ARRAY(limit, TMP105State, 2),
	VMSTATE_UINT8(alarm, TMP105State),
	VMSTATE_I2C_SLAVE(i2c, TMP105State),
	VMSTATE_END_OF_LIST()
	},
	.subsections = (const VMStateDescription*[]) {
	&vmstate_tmp105_detect_falling,
	NULL
	}
	};

	static void tmp105_reset(I2CSlave *i2c)
	{
	TMP105State *s = TMP105(i2c);

	s->temperature = 0;
	s->pointer = 0;
	s->config = 0;
	s->faults = tmp105_faultq[(s->config >> 3) & 3];
	s->alarm = 0;
	s->detect_falling = false;

	s->limit[0] = 0x4b00; /* T_LOW, 75 degrees C */
	s->limit[1] = 0x5000; /* T_HIGH, 80 degrees C */

	tmp105_interrupt_update(s);
	}

	static void tmp105_realize(DeviceState dev, Error *errp)
	{
	I2CSlave *i2c = I2C_SLAVE(dev);
	TMP105State *s = TMP105(i2c);

	qdev_init_gpio_out(&i2c->qdev, &s->pin, 1);

	tmp105_reset(&s->i2c);
	}

	static void tmp105_initfn(Object *obj)
	{
	object_property_add(obj, "temperature", "int",
	tmp105_get_temperature,
	tmp105_set_temperature, NULL, NULL);
	}

	static void tmp105_class_init(ObjectClass klass, void data)
	{
	DeviceClass *dc = DEVICE_CLASS(klass);
	I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);

	dc->realize = tmp105_realize;
	k->event = tmp105_event;
	k->recv = tmp105_rx;
	k->send = tmp105_tx;
	dc->vmsd = &vmstate_tmp105;
	}

	static const TypeInfo tmp105_info = {
	.name = TYPE_TMP105,
	.parent = TYPE_I2C_SLAVE,
	.instance_size = sizeof(TMP105State),
	.instance_init = tmp105_initfn,
	.class_init = tmp105_class_init,
	};

	static void tmp105_register_types(void)
	{
	type_register_static(&tmp105_info);
	}

	type_init(tmp105_register_types)