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-rw-r--r--hw/sensor/tmp105.c328
1 files changed, 328 insertions, 0 deletions
diff --git a/hw/sensor/tmp105.c b/hw/sensor/tmp105.c
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index 000000000..205644948
--- /dev/null
+++ b/hw/sensor/tmp105.c
@@ -0,0 +1,328 @@
+/*
+ * 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 = (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)