1 /*
2 * Texas Instruments TMP105 temperature sensor.
3 *
4 * Copyright (C) 2008 Nokia Corporation
5 * Written by Andrzej Zaborowski <andrew@openedhand.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation; either version 2 or
10 * (at your option) version 3 of the License.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "qemu/osdep.h"
22 #include "hw/i2c/i2c.h"
23 #include "hw/irq.h"
24 #include "migration/vmstate.h"
25 #include "tmp105.h"
26 #include "qapi/error.h"
27 #include "qapi/visitor.h"
28 #include "qemu/module.h"
29
tmp105_interrupt_update(TMP105State * s)30 static void tmp105_interrupt_update(TMP105State *s)
31 {
32 qemu_set_irq(s->pin, s->alarm ^ ((~s->config >> 2) & 1)); /* POL */
33 }
34
tmp105_alarm_update(TMP105State * s)35 static void tmp105_alarm_update(TMP105State *s)
36 {
37 if ((s->config >> 0) & 1) { /* SD */
38 if ((s->config >> 7) & 1) /* OS */
39 s->config &= ~(1 << 7); /* OS */
40 else
41 return;
42 }
43
44 if ((s->config >> 1) & 1) { /* TM */
45 if (s->temperature >= s->limit[1])
46 s->alarm = 1;
47 else if (s->temperature < s->limit[0])
48 s->alarm = 1;
49 } else {
50 if (s->temperature >= s->limit[1])
51 s->alarm = 1;
52 else if (s->temperature < s->limit[0])
53 s->alarm = 0;
54 }
55
56 tmp105_interrupt_update(s);
57 }
58
tmp105_get_temperature(Object * obj,Visitor * v,const char * name,void * opaque,Error ** errp)59 static void tmp105_get_temperature(Object *obj, Visitor *v, const char *name,
60 void *opaque, Error **errp)
61 {
62 TMP105State *s = TMP105(obj);
63 int64_t value = s->temperature * 1000 / 256;
64
65 visit_type_int(v, name, &value, errp);
66 }
67
68 /* Units are 0.001 centigrades relative to 0 C. s->temperature is 8.8
69 * fixed point, so units are 1/256 centigrades. A simple ratio will do.
70 */
tmp105_set_temperature(Object * obj,Visitor * v,const char * name,void * opaque,Error ** errp)71 static void tmp105_set_temperature(Object *obj, Visitor *v, const char *name,
72 void *opaque, Error **errp)
73 {
74 TMP105State *s = TMP105(obj);
75 Error *local_err = NULL;
76 int64_t temp;
77
78 visit_type_int(v, name, &temp, &local_err);
79 if (local_err) {
80 error_propagate(errp, local_err);
81 return;
82 }
83 if (temp >= 128000 || temp < -128000) {
84 error_setg(errp, "value %" PRId64 ".%03" PRIu64 " C is out of range",
85 temp / 1000, temp % 1000);
86 return;
87 }
88
89 s->temperature = (int16_t) (temp * 256 / 1000);
90
91 tmp105_alarm_update(s);
92 }
93
94 static const int tmp105_faultq[4] = { 1, 2, 4, 6 };
95
tmp105_read(TMP105State * s)96 static void tmp105_read(TMP105State *s)
97 {
98 s->len = 0;
99
100 if ((s->config >> 1) & 1) { /* TM */
101 s->alarm = 0;
102 tmp105_interrupt_update(s);
103 }
104
105 switch (s->pointer & 3) {
106 case TMP105_REG_TEMPERATURE:
107 s->buf[s->len ++] = (((uint16_t) s->temperature) >> 8);
108 s->buf[s->len ++] = (((uint16_t) s->temperature) >> 0) &
109 (0xf0 << ((~s->config >> 5) & 3)); /* R */
110 break;
111
112 case TMP105_REG_CONFIG:
113 s->buf[s->len ++] = s->config;
114 break;
115
116 case TMP105_REG_T_LOW:
117 s->buf[s->len ++] = ((uint16_t) s->limit[0]) >> 8;
118 s->buf[s->len ++] = ((uint16_t) s->limit[0]) >> 0;
119 break;
120
121 case TMP105_REG_T_HIGH:
122 s->buf[s->len ++] = ((uint16_t) s->limit[1]) >> 8;
123 s->buf[s->len ++] = ((uint16_t) s->limit[1]) >> 0;
124 break;
125 }
126 }
127
tmp105_write(TMP105State * s)128 static void tmp105_write(TMP105State *s)
129 {
130 switch (s->pointer & 3) {
131 case TMP105_REG_TEMPERATURE:
132 break;
133
134 case TMP105_REG_CONFIG:
135 if (s->buf[0] & ~s->config & (1 << 0)) /* SD */
136 printf("%s: TMP105 shutdown\n", __func__);
137 s->config = s->buf[0];
138 s->faults = tmp105_faultq[(s->config >> 3) & 3]; /* F */
139 tmp105_alarm_update(s);
140 break;
141
142 case TMP105_REG_T_LOW:
143 case TMP105_REG_T_HIGH:
144 if (s->len >= 3)
145 s->limit[s->pointer & 1] = (int16_t)
146 ((((uint16_t) s->buf[0]) << 8) | s->buf[1]);
147 tmp105_alarm_update(s);
148 break;
149 }
150 }
151
tmp105_rx(I2CSlave * i2c)152 static uint8_t tmp105_rx(I2CSlave *i2c)
153 {
154 TMP105State *s = TMP105(i2c);
155
156 if (s->len < 2) {
157 return s->buf[s->len ++];
158 } else {
159 return 0xff;
160 }
161 }
162
tmp105_tx(I2CSlave * i2c,uint8_t data)163 static int tmp105_tx(I2CSlave *i2c, uint8_t data)
164 {
165 TMP105State *s = TMP105(i2c);
166
167 if (s->len == 0) {
168 s->pointer = data;
169 s->len++;
170 } else {
171 if (s->len <= 2) {
172 s->buf[s->len - 1] = data;
173 }
174 s->len++;
175 tmp105_write(s);
176 }
177
178 return 0;
179 }
180
tmp105_event(I2CSlave * i2c,enum i2c_event event)181 static int tmp105_event(I2CSlave *i2c, enum i2c_event event)
182 {
183 TMP105State *s = TMP105(i2c);
184
185 if (event == I2C_START_RECV) {
186 tmp105_read(s);
187 }
188
189 s->len = 0;
190 return 0;
191 }
192
tmp105_post_load(void * opaque,int version_id)193 static int tmp105_post_load(void *opaque, int version_id)
194 {
195 TMP105State *s = opaque;
196
197 s->faults = tmp105_faultq[(s->config >> 3) & 3]; /* F */
198
199 tmp105_interrupt_update(s);
200 return 0;
201 }
202
203 static const VMStateDescription vmstate_tmp105 = {
204 .name = "TMP105",
205 .version_id = 0,
206 .minimum_version_id = 0,
207 .post_load = tmp105_post_load,
208 .fields = (VMStateField[]) {
209 VMSTATE_UINT8(len, TMP105State),
210 VMSTATE_UINT8_ARRAY(buf, TMP105State, 2),
211 VMSTATE_UINT8(pointer, TMP105State),
212 VMSTATE_UINT8(config, TMP105State),
213 VMSTATE_INT16(temperature, TMP105State),
214 VMSTATE_INT16_ARRAY(limit, TMP105State, 2),
215 VMSTATE_UINT8(alarm, TMP105State),
216 VMSTATE_I2C_SLAVE(i2c, TMP105State),
217 VMSTATE_END_OF_LIST()
218 }
219 };
220
tmp105_reset(I2CSlave * i2c)221 static void tmp105_reset(I2CSlave *i2c)
222 {
223 TMP105State *s = TMP105(i2c);
224
225 s->temperature = 0;
226 s->pointer = 0;
227 s->config = 0;
228 s->faults = tmp105_faultq[(s->config >> 3) & 3];
229 s->alarm = 0;
230
231 tmp105_interrupt_update(s);
232 }
233
tmp105_realize(DeviceState * dev,Error ** errp)234 static void tmp105_realize(DeviceState *dev, Error **errp)
235 {
236 I2CSlave *i2c = I2C_SLAVE(dev);
237 TMP105State *s = TMP105(i2c);
238
239 qdev_init_gpio_out(&i2c->qdev, &s->pin, 1);
240
241 tmp105_reset(&s->i2c);
242 }
243
tmp105_initfn(Object * obj)244 static void tmp105_initfn(Object *obj)
245 {
246 object_property_add(obj, "temperature", "int",
247 tmp105_get_temperature,
248 tmp105_set_temperature, NULL, NULL, NULL);
249 }
250
tmp105_class_init(ObjectClass * klass,void * data)251 static void tmp105_class_init(ObjectClass *klass, void *data)
252 {
253 DeviceClass *dc = DEVICE_CLASS(klass);
254 I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
255
256 dc->realize = tmp105_realize;
257 k->event = tmp105_event;
258 k->recv = tmp105_rx;
259 k->send = tmp105_tx;
260 dc->vmsd = &vmstate_tmp105;
261 }
262
263 static const TypeInfo tmp105_info = {
264 .name = TYPE_TMP105,
265 .parent = TYPE_I2C_SLAVE,
266 .instance_size = sizeof(TMP105State),
267 .instance_init = tmp105_initfn,
268 .class_init = tmp105_class_init,
269 };
270
tmp105_register_types(void)271 static void tmp105_register_types(void)
272 {
273 type_register_static(&tmp105_info);
274 }
275
276 type_init(tmp105_register_types)
277