1 /*
2 * Copyright (c) 2023 FTP Technologies
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #define DT_DRV_COMPAT current_sense_amplifier
8
9 #include <zephyr/drivers/adc.h>
10 #include <zephyr/drivers/adc/current_sense_amplifier.h>
11 #include <zephyr/drivers/gpio.h>
12 #include <zephyr/drivers/sensor.h>
13 #include <zephyr/pm/device.h>
14 #include <zephyr/sys/__assert.h>
15
16 #include <zephyr/logging/log.h>
17 LOG_MODULE_REGISTER(current_amp, CONFIG_SENSOR_LOG_LEVEL);
18
19 struct current_sense_amplifier_data {
20 struct adc_sequence sequence;
21 int16_t raw;
22 };
23
fetch(const struct device * dev,enum sensor_channel chan)24 static int fetch(const struct device *dev, enum sensor_channel chan)
25 {
26 const struct current_sense_amplifier_dt_spec *config = dev->config;
27 struct current_sense_amplifier_data *data = dev->data;
28 int ret;
29
30 if ((chan != SENSOR_CHAN_CURRENT) && (chan != SENSOR_CHAN_ALL)) {
31 return -ENOTSUP;
32 }
33
34 ret = adc_read_dt(&config->port, &data->sequence);
35 if (ret != 0) {
36 LOG_ERR("adc_read: %d", ret);
37 }
38
39 return ret;
40 }
41
get(const struct device * dev,enum sensor_channel chan,struct sensor_value * val)42 static int get(const struct device *dev, enum sensor_channel chan, struct sensor_value *val)
43 {
44 const struct current_sense_amplifier_dt_spec *config = dev->config;
45 struct current_sense_amplifier_data *data = dev->data;
46 int32_t raw_val = data->raw;
47 int32_t i_ma;
48 int ret;
49
50 __ASSERT_NO_MSG(val != NULL);
51
52 if (chan != SENSOR_CHAN_CURRENT) {
53 return -ENOTSUP;
54 }
55
56 ret = adc_raw_to_millivolts_dt(&config->port, &raw_val);
57 if (ret != 0) {
58 LOG_ERR("raw_to_mv: %d", ret);
59 return ret;
60 }
61
62 i_ma = raw_val;
63 current_sense_amplifier_scale_dt(config, &i_ma);
64
65 LOG_DBG("%d/%d, %dmV, current:%dmA", data->raw,
66 (1 << data->sequence.resolution) - 1, raw_val, i_ma);
67
68 val->val1 = i_ma / 1000;
69 val->val2 = (i_ma % 1000) * 1000;
70
71 return 0;
72 }
73
74 static DEVICE_API(sensor, current_api) = {
75 .sample_fetch = fetch,
76 .channel_get = get,
77 };
78
79 #ifdef CONFIG_PM_DEVICE
pm_action(const struct device * dev,enum pm_device_action action)80 static int pm_action(const struct device *dev, enum pm_device_action action)
81 {
82 const struct current_sense_amplifier_dt_spec *config = dev->config;
83 int ret;
84
85 if (config->power_gpio.port == NULL) {
86 LOG_ERR("PM not supported");
87 return -ENOTSUP;
88 }
89
90 switch (action) {
91 case PM_DEVICE_ACTION_RESUME:
92 ret = gpio_pin_set_dt(&config->power_gpio, 1);
93 if (ret != 0) {
94 LOG_ERR("failed to set GPIO for PM resume");
95 return ret;
96 }
97 break;
98 case PM_DEVICE_ACTION_SUSPEND:
99 ret = gpio_pin_set_dt(&config->power_gpio, 0);
100 if (ret != 0) {
101 LOG_ERR("failed to set GPIO for PM suspend");
102 return ret;
103 }
104 break;
105 default:
106 return -ENOTSUP;
107 }
108
109 return 0;
110 }
111 #endif
112
current_init(const struct device * dev)113 static int current_init(const struct device *dev)
114 {
115 const struct current_sense_amplifier_dt_spec *config = dev->config;
116 struct current_sense_amplifier_data *data = dev->data;
117 int ret;
118
119 __ASSERT(config->sense_milli_ohms != 0, "Milli-ohms must not be 0");
120
121 if (!adc_is_ready_dt(&config->port)) {
122 LOG_ERR("ADC is not ready");
123 return -ENODEV;
124 }
125
126 #ifdef CONFIG_PM_DEVICE
127 if (config->power_gpio.port != NULL) {
128 if (!gpio_is_ready_dt(&config->power_gpio)) {
129 LOG_ERR("Power GPIO is not ready");
130 return -ENODEV;
131 }
132
133 ret = gpio_pin_configure_dt(&config->power_gpio, GPIO_OUTPUT_ACTIVE);
134 if (ret != 0) {
135 LOG_ERR("failed to config GPIO: %d", ret);
136 return ret;
137 }
138 }
139 #endif
140
141 ret = adc_channel_setup_dt(&config->port);
142 if (ret != 0) {
143 LOG_ERR("setup: %d", ret);
144 return ret;
145 }
146
147 ret = adc_sequence_init_dt(&config->port, &data->sequence);
148 if (ret != 0) {
149 LOG_ERR("sequence init: %d", ret);
150 return ret;
151 }
152
153 data->sequence.buffer = &data->raw;
154 data->sequence.buffer_size = sizeof(data->raw);
155 data->sequence.calibrate = true;
156
157 return 0;
158 }
159
160 #define CURRENT_SENSE_AMPLIFIER_INIT(inst) \
161 static struct current_sense_amplifier_data current_amp_##inst##_data; \
162 \
163 static const struct current_sense_amplifier_dt_spec current_amp_##inst##_config = \
164 CURRENT_SENSE_AMPLIFIER_DT_SPEC_GET(DT_DRV_INST(inst)); \
165 \
166 PM_DEVICE_DT_INST_DEFINE(inst, pm_action); \
167 \
168 SENSOR_DEVICE_DT_INST_DEFINE(inst, ¤t_init, PM_DEVICE_DT_INST_GET(inst), \
169 ¤t_amp_##inst##_data, ¤t_amp_##inst##_config, \
170 POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY, ¤t_api);
171
172 DT_INST_FOREACH_STATUS_OKAY(CURRENT_SENSE_AMPLIFIER_INIT)
173
