1 /*
2  * Copyright (c) 2020 Vestas Wind Systems A/S
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 
7 #include <zephyr/device.h>
8 #include <zephyr/drivers/sensor.h>
9 #include <zephyr/drivers/sensor/mcux_acmp.h>
10 #include <zephyr/kernel.h>
11 
12 #include <stdio.h>
13 
14 #ifdef CONFIG_BOARD_TWR_KE18F
15 #define ACMP_NODE  DT_NODELABEL(cmp2)
16 #define ACMP_POSITIVE 5
17 #define ACMP_NEGATIVE 5
18 #define ACMP_DAC_VREF 0
19 #elif (defined(CONFIG_BOARD_MIMXRT1170_EVK) || defined(CONFIG_BOARD_MIMXRT1180_EVK))
20 #define ACMP_NODE  DT_NODELABEL(acmp1)
21 #define ACMP_POSITIVE 2
22 #define ACMP_NEGATIVE 7
23 /* Select Vin2. Vin1 is not used and tied to ground on this chip. Vin2 is from VDDA_1P8_IN. */
24 #define ACMP_DAC_VREF 1
25 #elif (defined(CONFIG_BOARD_FRDM_KE17Z) || defined(CONFIG_BOARD_FRDM_KE17Z512))
26 #define ACMP_NODE  DT_NODELABEL(cmp0)
27 #define ACMP_POSITIVE 4
28 #define ACMP_NEGATIVE 4
29 #define ACMP_DAC_VREF 0
30 #elif (defined(CONFIG_BOARD_MIMXRT700_EVK))
31 #define ACMP_NODE  DT_NODELABEL(acmp)
32 #define ACMP_POSITIVE 1
33 #define ACMP_NEGATIVE 7
34 #define ACMP_DAC_VREF 1
35 #else
36 #error Unsupported board
37 #endif
38 
39 #define ACMP_DAC_VALUE 128
40 
41 struct acmp_attr {
42 	int16_t attr;
43 	int32_t val;
44 };
45 
46 static const struct acmp_attr attrs[] = {
47 #if MCUX_ACMP_HAS_INPSEL
48 	/* Positive input port set to MUX */
49 	{ .attr = SENSOR_ATTR_MCUX_ACMP_POSITIVE_PORT_INPUT, .val = 1 },
50 #endif
51 	/* Positive input channel */
52 	{ .attr = SENSOR_ATTR_MCUX_ACMP_POSITIVE_MUX_INPUT,
53 	  .val = ACMP_POSITIVE },
54 #if MCUX_ACMP_HAS_INNSEL
55 	/* Negative input port set to DAC */
56 	{ .attr = SENSOR_ATTR_MCUX_ACMP_NEGATIVE_PORT_INPUT, .val = 0 },
57 #endif
58 	/* Negative input channel */
59 	{ .attr = SENSOR_ATTR_MCUX_ACMP_NEGATIVE_MUX_INPUT,
60 	  .val = ACMP_NEGATIVE },
61 	/* DAC voltage reference */
62 	{ .attr = SENSOR_ATTR_MCUX_ACMP_DAC_VOLTAGE_REFERENCE,
63 	  .val = ACMP_DAC_VREF },
64 	/* DAC value */
65 	{ .attr = SENSOR_ATTR_MCUX_ACMP_DAC_VALUE, .val = ACMP_DAC_VALUE },
66 #if MCUX_ACMP_HAS_HYSTCTR
67 	/* Hysteresis level */
68 	{ .attr = SENSOR_ATTR_MCUX_ACMP_HYSTERESIS_LEVEL, .val = 3 },
69 #endif
70 #if MCUX_ACMP_HAS_DISCRETE_MODE
71 	/* Discrete mode */
72 	{ .attr = SENSOR_ATTR_MCUX_ACMP_POSITIVE_DISCRETE_MODE, .val = 1 },
73 #endif
74 #if MCUX_ACMP_HAS_OFFSET
75 	/* Offset level */
76 	{ .attr = SENSOR_ATTR_MCUX_ACMP_OFFSET_LEVEL, .val = 0 },
77 #endif
78 };
79 
80 static const int16_t triggers[] = {
81 	SENSOR_TRIG_MCUX_ACMP_OUTPUT_RISING,
82 	SENSOR_TRIG_MCUX_ACMP_OUTPUT_FALLING,
83 };
84 
acmp_input_handler(bool above_threshold)85 static void acmp_input_handler(bool above_threshold)
86 {
87 	if (above_threshold) {
88 		printf("ACMP input above threshold\n");
89 	} else {
90 		printf("ACMP input below threshold\n");
91 	}
92 }
93 
acmp_trigger_handler(const struct device * dev,const struct sensor_trigger * trigger)94 static void acmp_trigger_handler(const struct device *dev,
95 				 const struct sensor_trigger *trigger)
96 {
97 	ARG_UNUSED(dev);
98 
99 	acmp_input_handler((int16_t)trigger->type ==
100 			   SENSOR_TRIG_MCUX_ACMP_OUTPUT_RISING);
101 }
102 
main(void)103 int main(void)
104 {
105 	struct sensor_trigger trigger[ARRAY_SIZE(triggers)] = {
106 		[0] = {
107 				.chan = SENSOR_CHAN_MCUX_ACMP_OUTPUT,
108 				.type = triggers[0],
109 			},
110 		[1] = {
111 			.chan = SENSOR_CHAN_MCUX_ACMP_OUTPUT,
112 			.type = triggers[1],
113 		}};
114 
115 	const struct device *const acmp = DEVICE_DT_GET(ACMP_NODE);
116 	struct sensor_value val;
117 	int err;
118 	int i;
119 
120 	if (!device_is_ready(acmp)) {
121 		printf("ACMP device not ready");
122 		return 0;
123 	}
124 
125 	/* Set ACMP attributes */
126 	val.val2 = 0;
127 	for (i = 0; i < ARRAY_SIZE(attrs); i++) {
128 		val.val1 = attrs[i].val;
129 		err = sensor_attr_set(acmp, SENSOR_CHAN_MCUX_ACMP_OUTPUT,
130 				      attrs[i].attr, &val);
131 		if (err) {
132 			printf("failed to set attribute %d (err %d)", i, err);
133 			return 0;
134 		}
135 	}
136 
137 	/* Delay for analog components (DAC, CMP, ...) to settle */
138 	k_sleep(K_MSEC(1));
139 
140 	/* Set ACMP triggers */
141 	for (i = 0; i < ARRAY_SIZE(triggers); i++) {
142 		err = sensor_trigger_set(acmp, &trigger[i], acmp_trigger_handler);
143 		if (err) {
144 			printf("failed to set trigger %d (err %d)", i, err);
145 			return 0;
146 		}
147 	}
148 
149 	printf("Adjust ACMP input voltage by turning the potentiometer\n");
150 
151 	/* Read initial state */
152 	err = sensor_sample_fetch(acmp);
153 	if (err) {
154 		printf("failed to fetch sample (err %d)", err);
155 		return 0;
156 	}
157 
158 	err = sensor_channel_get(acmp, SENSOR_CHAN_MCUX_ACMP_OUTPUT, &val);
159 	if (err) {
160 		printf("failed to get channel (err %d)", err);
161 		return 0;
162 	}
163 
164 	acmp_input_handler(val.val1 == 1);
165 
166 	/* Await trigger */
167 	while (true) {
168 		k_sleep(K_MSEC(1));
169 	}
170 	return 0;
171 }
172