1 /*
2 * Copyright (c) 2018 Analog Devices Inc.
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/kernel.h>
8 #include <zephyr/device.h>
9 #include <zephyr/drivers/sensor.h>
10 #include <stdio.h>
11 #include <zephyr/sys/__assert.h>
12
13 #define DELAY_WITH_TRIGGER K_SECONDS(5)
14 #define DELAY_WITHOUT_TRIGGER K_SECONDS(1)
15
16 #define UCEL_PER_CEL 1000000
17 #define UCEL_PER_MCEL 1000
18 #define TEMP_INITIAL_CEL 21
19 #define TEMP_WINDOW_HALF_UCEL 500000
20
21 K_SEM_DEFINE(sem, 0, 1);
now_str(void)22 static const char *now_str(void)
23 {
24 static char buf[16]; /* ...HH:MM:SS.MMM */
25 uint32_t now = k_uptime_get_32();
26 unsigned int ms = now % MSEC_PER_SEC;
27 unsigned int s;
28 unsigned int min;
29 unsigned int h;
30
31 now /= MSEC_PER_SEC;
32 s = now % 60U;
33 now /= 60U;
34 min = now % 60U;
35 now /= 60U;
36 h = now;
37
38 snprintf(buf, sizeof(buf), "%u:%02u:%02u.%03u",
39 h, min, s, ms);
40 return buf;
41 }
trigger_handler(const struct device * dev,const struct sensor_trigger * trigger)42 static void trigger_handler(const struct device *dev,
43 const struct sensor_trigger *trigger)
44 {
45 k_sem_give(&sem);
46 }
47
48 static int low_ucel;
49 static int high_ucel;
50
sensor_set_attribute(const struct device * dev,enum sensor_channel chan,enum sensor_attribute attr,int value)51 static int sensor_set_attribute(const struct device *dev,
52 enum sensor_channel chan,
53 enum sensor_attribute attr, int value)
54 {
55 struct sensor_value sensor_val;
56 int ret;
57
58 sensor_val.val1 = value / UCEL_PER_CEL;
59 sensor_val.val2 = value % UCEL_PER_CEL;
60
61 ret = sensor_attr_set(dev, chan, attr, &sensor_val);
62 if (ret) {
63 printf("sensor_attr_set failed ret %d\n", ret);
64 }
65
66 return ret;
67 }
68
temp_in_window(const struct sensor_value * val)69 static bool temp_in_window(const struct sensor_value *val)
70 {
71 int temp_ucel = val->val1 * UCEL_PER_CEL + val->val2;
72
73 return (temp_ucel >= low_ucel) && (temp_ucel <= high_ucel);
74 }
75
sensor_set_window(const struct device * dev,const struct sensor_value * val)76 static int sensor_set_window(const struct device *dev,
77 const struct sensor_value *val)
78 {
79 int temp_ucel = val->val1 * UCEL_PER_CEL + val->val2;
80
81 low_ucel = temp_ucel - TEMP_WINDOW_HALF_UCEL;
82 high_ucel = temp_ucel + TEMP_WINDOW_HALF_UCEL;
83
84 int rc = sensor_set_attribute(dev, SENSOR_CHAN_AMBIENT_TEMP,
85 SENSOR_ATTR_UPPER_THRESH, high_ucel);
86
87 if (rc == 0) {
88 sensor_set_attribute(dev, SENSOR_CHAN_AMBIENT_TEMP,
89 SENSOR_ATTR_LOWER_THRESH, low_ucel);
90 }
91
92 if (rc == 0) {
93 printk("Alert on temp outside [%d, %d] mCel\n",
94 low_ucel / UCEL_PER_MCEL,
95 high_ucel / UCEL_PER_MCEL);
96 }
97
98 return rc;
99 }
100
process(const struct device * dev)101 static void process(const struct device *dev)
102 {
103 struct sensor_value temp_val;
104 int ret;
105 bool reset_window = false;
106
107 /* Set update rate to 240 mHz */
108 sensor_set_attribute(dev, SENSOR_CHAN_AMBIENT_TEMP,
109 SENSOR_ATTR_SAMPLING_FREQUENCY, 240 * 1000);
110
111 if (IS_ENABLED(CONFIG_ADT7420_TRIGGER)) {
112 struct sensor_trigger trig = {
113 .type = SENSOR_TRIG_THRESHOLD,
114 .chan = SENSOR_CHAN_AMBIENT_TEMP,
115 };
116 struct sensor_value val = {
117 .val1 = TEMP_INITIAL_CEL,
118 };
119
120 ret = sensor_set_window(dev, &val);
121 if (ret == 0) {
122 ret = sensor_trigger_set(dev, &trig, trigger_handler);
123 }
124 if (ret != 0) {
125 printf("Could not set trigger\n");
126 return;
127 }
128 }
129
130 while (1) {
131 ret = sensor_sample_fetch(dev);
132 if (ret) {
133 printf("sensor_sample_fetch failed ret %d\n", ret);
134 return;
135 }
136
137 ret = sensor_channel_get(dev, SENSOR_CHAN_AMBIENT_TEMP,
138 &temp_val);
139 if (ret) {
140 printf("sensor_channel_get failed ret %d\n", ret);
141 return;
142 }
143
144 if (IS_ENABLED(CONFIG_ADT7420_TRIGGER)) {
145 reset_window |= !temp_in_window(&temp_val);
146 }
147
148 printf("[%s]: temperature %.6f Cel%s\n", now_str(),
149 sensor_value_to_double(&temp_val),
150 reset_window ? ": NEED RESET" : "");
151
152
153 if (IS_ENABLED(CONFIG_ADT7420_TRIGGER)) {
154 if (reset_window) {
155 ret = sensor_set_window(dev, &temp_val);
156 }
157 if (ret) {
158 printf("Window update failed ret %d\n", ret);
159 return;
160 }
161
162 printk("Wait for trigger...");
163 ret = k_sem_take(&sem, DELAY_WITH_TRIGGER);
164 reset_window = (ret == 0);
165 printk("%s\n", reset_window ? "ALERTED!" : "timed-out");
166 } else {
167 k_sleep(DELAY_WITHOUT_TRIGGER);
168 }
169 }
170 }
171
main(void)172 int main(void)
173 {
174 const struct device *const dev = DEVICE_DT_GET_ONE(adi_adt7420);
175
176 if (!device_is_ready(dev)) {
177 printk("sensor: device not ready.\n");
178 return 0;
179 }
180
181 printf("device is %p, name is %s\n", dev, dev->name);
182
183 process(dev);
184 return 0;
185 }
186
