iio_event_monitor.c

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/* Industrialio event test code.
 *
 * Copyright (c) 2011-2012 Lars-Peter Clausen <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is primarily intended as an example application.
 * Reads the current buffer setup from sysfs and starts a short capture
 * from the specified device, pretty printing the result after appropriate
 * conversion.
 *
 * Usage:
 *  iio_event_monitor <device_name>
 *
 */

#define _GNU_SOURCE

#include <unistd.h>
#include <stdbool.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <poll.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include "iio_utils.h"
#include <linux/iio/events.h>

static const char * const iio_chan_type_name_spec[] = {
    [IIO_VOLTAGE] = "voltage",
    [IIO_CURRENT] = "current",
    [IIO_POWER] = "power",
    [IIO_ACCEL] = "accel",
    [IIO_ANGL_VEL] = "anglvel",
    [IIO_MAGN] = "magn",
    [IIO_LIGHT] = "illuminance",
    [IIO_INTENSITY] = "intensity",
    [IIO_PROXIMITY] = "proximity",
    [IIO_TEMP] = "temp",
    [IIO_INCLI] = "incli",
    [IIO_ROT] = "rot",
    [IIO_ANGL] = "angl",
    [IIO_TIMESTAMP] = "timestamp",
    [IIO_CAPACITANCE] = "capacitance",
    [IIO_ALTVOLTAGE] = "altvoltage",
};

static const char * const iio_ev_type_text[] = {
    [IIO_EV_TYPE_THRESH] = "thresh",
    [IIO_EV_TYPE_MAG] = "mag",
    [IIO_EV_TYPE_ROC] = "roc",
    [IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
    [IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
};

static const char * const iio_ev_dir_text[] = {
    [IIO_EV_DIR_EITHER] = "either",
    [IIO_EV_DIR_RISING] = "rising",
    [IIO_EV_DIR_FALLING] = "falling"
};

static const char * const iio_modifier_names[] = {
    [IIO_MOD_X] = "x",
    [IIO_MOD_Y] = "y",
    [IIO_MOD_Z] = "z",
    [IIO_MOD_LIGHT_BOTH] = "both",
    [IIO_MOD_LIGHT_IR] = "ir",
    [IIO_MOD_ROOT_SUM_SQUARED_X_Y] = "sqrt(x^2+y^2)",
    [IIO_MOD_SUM_SQUARED_X_Y_Z] = "x^2+y^2+z^2",
    [IIO_MOD_LIGHT_CLEAR] = "clear",
    [IIO_MOD_LIGHT_RED] = "red",
    [IIO_MOD_LIGHT_GREEN] = "green",
    [IIO_MOD_LIGHT_BLUE] = "blue",
};

static bool event_is_known(struct iio_event_data *event)
{
    enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
    enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
    enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
    enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);

    switch (type) {
    case IIO_VOLTAGE:
    case IIO_CURRENT:
    case IIO_POWER:
    case IIO_ACCEL:
    case IIO_ANGL_VEL:
    case IIO_MAGN:
    case IIO_LIGHT:
    case IIO_INTENSITY:
    case IIO_PROXIMITY:
    case IIO_TEMP:
    case IIO_INCLI:
    case IIO_ROT:
    case IIO_ANGL:
    case IIO_TIMESTAMP:
    case IIO_CAPACITANCE:
    case IIO_ALTVOLTAGE:
        break;
    default:
        return false;
    }

    switch (mod) {
    case IIO_NO_MOD:
    case IIO_MOD_X:
    case IIO_MOD_Y:
    case IIO_MOD_Z:
    case IIO_MOD_LIGHT_BOTH:
    case IIO_MOD_LIGHT_IR:
    case IIO_MOD_ROOT_SUM_SQUARED_X_Y:
    case IIO_MOD_SUM_SQUARED_X_Y_Z:
    case IIO_MOD_LIGHT_CLEAR:
    case IIO_MOD_LIGHT_RED:
    case IIO_MOD_LIGHT_GREEN:
    case IIO_MOD_LIGHT_BLUE:
        break;
    default:
        return false;
    }

    switch (ev_type) {
    case IIO_EV_TYPE_THRESH:
    case IIO_EV_TYPE_MAG:
    case IIO_EV_TYPE_ROC:
    case IIO_EV_TYPE_THRESH_ADAPTIVE:
    case IIO_EV_TYPE_MAG_ADAPTIVE:
        break;
    default:
        return false;
    }

    switch (dir) {
    case IIO_EV_DIR_EITHER:
    case IIO_EV_DIR_RISING:
    case IIO_EV_DIR_FALLING:
        break;
    default:
        return false;
    }

    return true;
}

static void print_event(struct iio_event_data *event)
{
    enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
    enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
    enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
    enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);
    int chan = IIO_EVENT_CODE_EXTRACT_CHAN(event->id);
    int chan2 = IIO_EVENT_CODE_EXTRACT_CHAN2(event->id);
    bool diff = IIO_EVENT_CODE_EXTRACT_DIFF(event->id);

    if (!event_is_known(event)) {
        printf("Unknown event: time: %lld, id: %llx\n",
                event->timestamp, event->id);
        return;
    }

    printf("Event: time: %lld, ", event->timestamp);

    if (mod != IIO_NO_MOD) {
        printf("type: %s(%s), ",
            iio_chan_type_name_spec[type],
            iio_modifier_names[mod]);
    } else {
        printf("type: %s, ",
            iio_chan_type_name_spec[type]);
    }

    if (diff && chan >= 0 && chan2 >= 0)
        printf("channel: %d-%d, ", chan, chan2);
    else if (chan >= 0)
        printf("channel: %d, ", chan);

    printf("evtype: %s, direction: %s\n",
        iio_ev_type_text[ev_type],
        iio_ev_dir_text[dir]);
}

int main(int argc, char **argv)
{
    struct iio_event_data event;
    const char *device_name;
    char *chrdev_name;
    int ret;
    int dev_num;
    int fd, event_fd;

    if (argc <= 1) {
        printf("Usage: %s <device_name>\n", argv[0]);
        return -1;
    }

    device_name = argv[1];

    dev_num = find_type_by_name(device_name, "iio:device");
    if (dev_num >= 0) {
        printf("Found IIO device with name %s with device number %d\n",
            device_name, dev_num);
        ret = asprintf(&chrdev_name, "/dev/iio:device%d", dev_num);
        if (ret < 0) {
            ret = -ENOMEM;
            goto error_ret;
        }
    } else {
        /* If we can't find a IIO device by name assume device_name is a
           IIO chrdev */
        chrdev_name = strdup(device_name);
    }

    fd = open(chrdev_name, 0);
    if (fd == -1) {
        fprintf(stdout, "Failed to open %s\n", chrdev_name);
        ret = -errno;
        goto error_free_chrdev_name;
    }

    ret = ioctl(fd, IIO_GET_EVENT_FD_IOCTL, &event_fd);

    close(fd);

    if (ret == -1 || event_fd == -1) {
        fprintf(stdout, "Failed to retrieve event fd\n");
        ret = -errno;
        goto error_free_chrdev_name;
    }

    while (true) {
        ret = read(event_fd, &event, sizeof(event));
        if (ret == -1) {
            if (errno == EAGAIN) {
                printf("nothing available\n");
                continue;
            } else {
                perror("Failed to read event from device");
                ret = -errno;
                break;
            }
        }

        print_event(&event);
    }

    close(event_fd);
error_free_chrdev_name:
    free(chrdev_name);
error_ret:
    return ret;
}