1 /* ST Microelectronics STTS751 temperature sensor
2 *
3 * Copyright (c) 2019 STMicroelectronics
4 *
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Datasheet:
8 * https://www.st.com/resource/en/datasheet/stts751.pdf
9 */
10
11 #define DT_DRV_COMPAT st_stts751
12
13 #include <zephyr/drivers/sensor.h>
14 #include <zephyr/kernel.h>
15 #include <zephyr/device.h>
16 #include <zephyr/init.h>
17 #include <zephyr/sys/byteorder.h>
18 #include <zephyr/sys/__assert.h>
19 #include <zephyr/logging/log.h>
20
21 #include "stts751.h"
22
23 LOG_MODULE_REGISTER(STTS751, CONFIG_SENSOR_LOG_LEVEL);
24
stts751_set_odr_raw(const struct device * dev,uint8_t odr)25 static inline int stts751_set_odr_raw(const struct device *dev, uint8_t odr)
26 {
27 struct stts751_data *data = dev->data;
28
29 return stts751_temp_data_rate_set(data->ctx, odr);
30 }
31
stts751_sample_fetch(const struct device * dev,enum sensor_channel chan)32 static int stts751_sample_fetch(const struct device *dev,
33 enum sensor_channel chan)
34 {
35 struct stts751_data *data = dev->data;
36 int16_t raw_temp;
37
38 __ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL);
39
40 if (stts751_temperature_raw_get(data->ctx, &raw_temp) < 0) {
41 LOG_DBG("Failed to read sample");
42 return -EIO;
43 }
44
45 data->sample_temp = raw_temp;
46
47 return 0;
48 }
49
stts751_temp_convert(struct sensor_value * val,int16_t raw_val)50 static inline void stts751_temp_convert(struct sensor_value *val,
51 int16_t raw_val)
52 {
53 val->val1 = raw_val / 256;
54 val->val2 = ((int32_t)raw_val % 256) * 10000;
55 }
56
stts751_channel_get(const struct device * dev,enum sensor_channel chan,struct sensor_value * val)57 static int stts751_channel_get(const struct device *dev,
58 enum sensor_channel chan,
59 struct sensor_value *val)
60 {
61 struct stts751_data *data = dev->data;
62
63 if (chan == SENSOR_CHAN_AMBIENT_TEMP) {
64 stts751_temp_convert(val, data->sample_temp);
65 } else {
66 return -ENOTSUP;
67 }
68
69 return 0;
70 }
71
72 static const struct {
73 int32_t rate;
74 int32_t rate_dec;
75 } stts751_map[] = {
76 {0, 62500},
77 {0, 125000},
78 {0, 250000},
79 {0, 500000},
80 {1, 0},
81 {2, 0},
82 {4, 0},
83 {8, 0},
84 {16, 0},
85 {32, 0},
86 };
87
stts751_odr_set(const struct device * dev,const struct sensor_value * val)88 static int stts751_odr_set(const struct device *dev,
89 const struct sensor_value *val)
90 {
91 int odr;
92
93 for (odr = 0; odr < ARRAY_SIZE(stts751_map); odr++) {
94 if (val->val1 == stts751_map[odr].rate &&
95 val->val2 == stts751_map[odr].rate_dec) {
96 break;
97 }
98 }
99
100 if (odr == ARRAY_SIZE(stts751_map)) {
101 LOG_DBG("bad frequency");
102 return -EINVAL;
103 }
104
105 if (stts751_set_odr_raw(dev, odr) < 0) {
106 LOG_DBG("failed to set sampling rate");
107 return -EIO;
108 }
109
110 return 0;
111 }
112
stts751_attr_set(const struct device * dev,enum sensor_channel chan,enum sensor_attribute attr,const struct sensor_value * val)113 static int stts751_attr_set(const struct device *dev,
114 enum sensor_channel chan,
115 enum sensor_attribute attr,
116 const struct sensor_value *val)
117 {
118 if (chan != SENSOR_CHAN_ALL) {
119 LOG_WRN("attr_set() not supported on this channel.");
120 return -ENOTSUP;
121 }
122
123 switch (attr) {
124 case SENSOR_ATTR_SAMPLING_FREQUENCY:
125 return stts751_odr_set(dev, val);
126 default:
127 LOG_DBG("operation not supported.");
128 return -ENOTSUP;
129 }
130
131 return 0;
132 }
133
134 static const struct sensor_driver_api stts751_api_funcs = {
135 .attr_set = stts751_attr_set,
136 .sample_fetch = stts751_sample_fetch,
137 .channel_get = stts751_channel_get,
138 #if CONFIG_STTS751_TRIGGER
139 .trigger_set = stts751_trigger_set,
140 #endif
141 };
142
stts751_init_chip(const struct device * dev)143 static int stts751_init_chip(const struct device *dev)
144 {
145 struct stts751_data *data = dev->data;
146 stts751_id_t chip_id;
147
148 if (stts751_device_id_get(data->ctx, &chip_id) < 0) {
149 LOG_DBG("Failed reading chip id");
150 return -EIO;
151 }
152
153 if (chip_id.manufacturer_id != STTS751_ID_MAN) {
154 LOG_DBG("Invalid chip id 0x%x", chip_id.manufacturer_id);
155 return -EIO;
156 }
157
158 if (stts751_set_odr_raw(dev, CONFIG_STTS751_SAMPLING_RATE) < 0) {
159 LOG_DBG("Failed to set sampling rate");
160 return -EIO;
161 }
162
163 if (stts751_resolution_set(data->ctx, STTS751_11bit) < 0) {
164 LOG_DBG("Failed to set resolution");
165 return -EIO;
166 }
167
168 return 0;
169 }
170
stts751_init(const struct device * dev)171 static int stts751_init(const struct device *dev)
172 {
173 const struct stts751_config * const config = dev->config;
174 struct stts751_data *data = dev->data;
175
176 data->dev = dev;
177
178 if (!device_is_ready(config->i2c.bus)) {
179 LOG_ERR("Bus device is not ready");
180 return -ENODEV;
181 }
182
183 config->bus_init(dev);
184
185 if (stts751_init_chip(dev) < 0) {
186 LOG_DBG("Failed to initialize chip");
187 return -EIO;
188 }
189
190 #ifdef CONFIG_STTS751_TRIGGER
191 if (config->int_gpio.port) {
192 if (stts751_init_interrupt(dev) < 0) {
193 LOG_ERR("Failed to initialize interrupt.");
194 return -EIO;
195 }
196 }
197 #endif
198
199 return 0;
200 }
201
202 #define STTS751_DEFINE(inst) \
203 static struct stts751_data stts751_data_##inst; \
204 \
205 static const struct stts751_config stts751_config_##inst = { \
206 COND_CODE_1(DT_INST_ON_BUS(inst, i2c), \
207 (.i2c = I2C_DT_SPEC_INST_GET(inst), \
208 .bus_init = stts751_i2c_init,), \
209 ()) \
210 IF_ENABLED(CONFIG_STTS751_TRIGGER, \
211 (.int_gpio = GPIO_DT_SPEC_INST_GET_OR(inst, drdy_gpios, { 0 }),)) \
212 }; \
213 \
214 SENSOR_DEVICE_DT_INST_DEFINE(inst, stts751_init, NULL, \
215 &stts751_data_##inst, &stts751_config_##inst, POST_KERNEL, \
216 CONFIG_SENSOR_INIT_PRIORITY, &stts751_api_funcs); \
217
218 DT_INST_FOREACH_STATUS_OKAY(STTS751_DEFINE)
219
