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iio_event_monitor.c
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1 /* Industrialio event test code.
2  *
3  * Copyright (c) 2011-2012 Lars-Peter Clausen <[email protected]>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 as published by
7  * the Free Software Foundation.
8  *
9  * This program is primarily intended as an example application.
10  * Reads the current buffer setup from sysfs and starts a short capture
11  * from the specified device, pretty printing the result after appropriate
12  * conversion.
13  *
14  * Usage:
15  * iio_event_monitor <device_name>
16  *
17  */
18 
19 #define _GNU_SOURCE
20 
21 #include <unistd.h>
22 #include <stdbool.h>
23 #include <stdio.h>
24 #include <errno.h>
25 #include <string.h>
26 #include <poll.h>
27 #include <fcntl.h>
28 #include <sys/ioctl.h>
29 #include "iio_utils.h"
30 #include <linux/iio/events.h>
31 
32 static const char * const iio_chan_type_name_spec[] = {
33  [IIO_VOLTAGE] = "voltage",
34  [IIO_CURRENT] = "current",
35  [IIO_POWER] = "power",
36  [IIO_ACCEL] = "accel",
37  [IIO_ANGL_VEL] = "anglvel",
38  [IIO_MAGN] = "magn",
39  [IIO_LIGHT] = "illuminance",
40  [IIO_INTENSITY] = "intensity",
41  [IIO_PROXIMITY] = "proximity",
42  [IIO_TEMP] = "temp",
43  [IIO_INCLI] = "incli",
44  [IIO_ROT] = "rot",
45  [IIO_ANGL] = "angl",
46  [IIO_TIMESTAMP] = "timestamp",
47  [IIO_CAPACITANCE] = "capacitance",
48  [IIO_ALTVOLTAGE] = "altvoltage",
49 };
50 
51 static const char * const iio_ev_type_text[] = {
52  [IIO_EV_TYPE_THRESH] = "thresh",
53  [IIO_EV_TYPE_MAG] = "mag",
54  [IIO_EV_TYPE_ROC] = "roc",
55  [IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
56  [IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
57 };
58 
59 static const char * const iio_ev_dir_text[] = {
60  [IIO_EV_DIR_EITHER] = "either",
61  [IIO_EV_DIR_RISING] = "rising",
62  [IIO_EV_DIR_FALLING] = "falling"
63 };
64 
65 static const char * const iio_modifier_names[] = {
66  [IIO_MOD_X] = "x",
67  [IIO_MOD_Y] = "y",
68  [IIO_MOD_Z] = "z",
69  [IIO_MOD_LIGHT_BOTH] = "both",
70  [IIO_MOD_LIGHT_IR] = "ir",
71  [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
72  [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
73  [IIO_MOD_LIGHT_CLEAR] = "clear",
74  [IIO_MOD_LIGHT_RED] = "red",
75  [IIO_MOD_LIGHT_GREEN] = "green",
76  [IIO_MOD_LIGHT_BLUE] = "blue",
77 };
78 
79 static bool event_is_known(struct iio_event_data *event)
80 {
83  enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
85 
86  switch (type) {
87  case IIO_VOLTAGE:
88  case IIO_CURRENT:
89  case IIO_POWER:
90  case IIO_ACCEL:
91  case IIO_ANGL_VEL:
92  case IIO_MAGN:
93  case IIO_LIGHT:
94  case IIO_INTENSITY:
95  case IIO_PROXIMITY:
96  case IIO_TEMP:
97  case IIO_INCLI:
98  case IIO_ROT:
99  case IIO_ANGL:
100  case IIO_TIMESTAMP:
101  case IIO_CAPACITANCE:
102  case IIO_ALTVOLTAGE:
103  break;
104  default:
105  return false;
106  }
107 
108  switch (mod) {
109  case IIO_NO_MOD:
110  case IIO_MOD_X:
111  case IIO_MOD_Y:
112  case IIO_MOD_Z:
113  case IIO_MOD_LIGHT_BOTH:
114  case IIO_MOD_LIGHT_IR:
117  case IIO_MOD_LIGHT_CLEAR:
118  case IIO_MOD_LIGHT_RED:
119  case IIO_MOD_LIGHT_GREEN:
120  case IIO_MOD_LIGHT_BLUE:
121  break;
122  default:
123  return false;
124  }
125 
126  switch (ev_type) {
127  case IIO_EV_TYPE_THRESH:
128  case IIO_EV_TYPE_MAG:
129  case IIO_EV_TYPE_ROC:
132  break;
133  default:
134  return false;
135  }
136 
137  switch (dir) {
138  case IIO_EV_DIR_EITHER:
139  case IIO_EV_DIR_RISING:
140  case IIO_EV_DIR_FALLING:
141  break;
142  default:
143  return false;
144  }
145 
146  return true;
147 }
148 
149 static void print_event(struct iio_event_data *event)
150 {
153  enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
155  int chan = IIO_EVENT_CODE_EXTRACT_CHAN(event->id);
156  int chan2 = IIO_EVENT_CODE_EXTRACT_CHAN2(event->id);
157  bool diff = IIO_EVENT_CODE_EXTRACT_DIFF(event->id);
158 
159  if (!event_is_known(event)) {
160  printf("Unknown event: time: %lld, id: %llx\n",
161  event->timestamp, event->id);
162  return;
163  }
164 
165  printf("Event: time: %lld, ", event->timestamp);
166 
167  if (mod != IIO_NO_MOD) {
168  printf("type: %s(%s), ",
169  iio_chan_type_name_spec[type],
170  iio_modifier_names[mod]);
171  } else {
172  printf("type: %s, ",
173  iio_chan_type_name_spec[type]);
174  }
175 
176  if (diff && chan >= 0 && chan2 >= 0)
177  printf("channel: %d-%d, ", chan, chan2);
178  else if (chan >= 0)
179  printf("channel: %d, ", chan);
180 
181  printf("evtype: %s, direction: %s\n",
182  iio_ev_type_text[ev_type],
183  iio_ev_dir_text[dir]);
184 }
185 
186 int main(int argc, char **argv)
187 {
188  struct iio_event_data event;
189  const char *device_name;
190  char *chrdev_name;
191  int ret;
192  int dev_num;
193  int fd, event_fd;
194 
195  if (argc <= 1) {
196  printf("Usage: %s <device_name>\n", argv[0]);
197  return -1;
198  }
199 
200  device_name = argv[1];
201 
202  dev_num = find_type_by_name(device_name, "iio:device");
203  if (dev_num >= 0) {
204  printf("Found IIO device with name %s with device number %d\n",
205  device_name, dev_num);
206  ret = asprintf(&chrdev_name, "/dev/iio:device%d", dev_num);
207  if (ret < 0) {
208  ret = -ENOMEM;
209  goto error_ret;
210  }
211  } else {
212  /* If we can't find a IIO device by name assume device_name is a
213  IIO chrdev */
214  chrdev_name = strdup(device_name);
215  }
216 
217  fd = open(chrdev_name, 0);
218  if (fd == -1) {
219  fprintf(stdout, "Failed to open %s\n", chrdev_name);
220  ret = -errno;
221  goto error_free_chrdev_name;
222  }
223 
224  ret = ioctl(fd, IIO_GET_EVENT_FD_IOCTL, &event_fd);
225 
226  close(fd);
227 
228  if (ret == -1 || event_fd == -1) {
229  fprintf(stdout, "Failed to retrieve event fd\n");
230  ret = -errno;
231  goto error_free_chrdev_name;
232  }
233 
234  while (true) {
235  ret = read(event_fd, &event, sizeof(event));
236  if (ret == -1) {
237  if (errno == EAGAIN) {
238  printf("nothing available\n");
239  continue;
240  } else {
241  perror("Failed to read event from device");
242  ret = -errno;
243  break;
244  }
245  }
246 
247  print_event(&event);
248  }
249 
250  close(event_fd);
251 error_free_chrdev_name:
252  free(chrdev_name);
253 error_ret:
254  return ret;
255 }