blob: a8730d0b7f97362110163a08e1b5e06f52a2a166 [file] [log] [blame]
/*
* 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 "hw/sensor/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 = (const 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 = (const 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 * const []) {
&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)