+++ /dev/null
-/* Industrialio ring buffer with a lis3l02dq accelerometer
- *
- * Copyright (c) 2008 Jonathan Cameron
- *
- * 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.
- */
-
-#include <dirent.h>
-#include <fcntl.h>
-#include <stdio.h>
-#include <errno.h>
-#include <sys/stat.h>
-#include <sys/dir.h>
-#include <linux/types.h>
-#include "iio_utils.h"
-
-const char *device_name = "lis3l02dq";
-const char *trigger_name_base = "lis3l02dq-dev";
-const int num_vals = 3;
-const int scan_ts = 1;
-const int buf_len = 128;
-const int num_loops = 10;
-
-/*
- * Could get this from ring bps, but only after starting the ring
- * which is a bit late for it to be useful.
- *
- * Todo: replace with much more generic version based on scan_elements
- * directory.
- */
-int size_from_scanmode(int num_vals, int timestamp)
-{
- if (num_vals && timestamp)
- return 16;
- else if (timestamp)
- return 8;
- else
- return num_vals*2;
-}
-
-int main(int argc, char **argv)
-{
- int ret;
- int i, j, k, toread;
- FILE *fp_ev;
- int fp;
-
- char *trigger_name, *dev_dir_name, *buf_dir_name;
- char *data;
- size_t read_size;
- struct iio_event_data dat;
- int dev_num, trig_num;
-
- char *buffer_access, *buffer_event;
- const char *iio_dir = "/sys/bus/iio/devices/";
- int scan_size;
- float gain = 1;
-
-
- /* Find out which iio device is the accelerometer. */
- dev_num = find_type_by_name(device_name, "device");
- if (dev_num < 0) {
- printf("Failed to find the %s\n", device_name);
- ret = -ENODEV;
- goto error_ret;
- }
- printf("iio device number being used is %d\n", dev_num);
- asprintf(&dev_dir_name, "%sdevice%d", iio_dir, dev_num);
-
- /*
- * Build the trigger name.
- * In this case we want the lis3l02dq's data ready trigger
- * for this lis3l02dq. The naming is lis3l02dq_dev[n], where
- * n matches the device number found above.
- */
- ret = asprintf(&trigger_name, "%s%d", trigger_name_base, dev_num);
- if (ret < 0) {
- ret = -ENOMEM;
- goto error_free_dev_dir_name;
- }
-
- /*
- * Find the trigger by name.
- * This is techically unecessary here as we only need to
- * refer to the trigger by name and that name is already
- * known.
- */
- trig_num = find_type_by_name(trigger_name, "trigger");
- if (trig_num < 0) {
- printf("Failed to find the %s\n", trigger_name);
- ret = -ENODEV;
- goto error_free_triggername;
- }
- printf("iio trigger number being used is %d\n", trig_num);
-
- /*
- * Read in the scale value - in a more generic case, first
- * check for accel_scale, then the indivual channel scales
- */
- ret = read_sysfs_float("accel_scale", dev_dir_name, &gain);
- if (ret)
- goto error_free_triggername;;
-
- /*
- * Construct the directory name for the associated buffer.
- * As we know that the lis3l02dq has only one buffer this may
- * be built rather than found.
- */
- ret = asprintf(&buf_dir_name, "%sdevice%d:buffer0", iio_dir, dev_num);
- if (ret < 0) {
- ret = -ENOMEM;
- goto error_free_triggername;
- }
- /* Set the device trigger to be the data rdy trigger found above */
- ret = write_sysfs_string_and_verify("trigger/current_trigger",
- dev_dir_name,
- trigger_name);
- if (ret < 0) {
- printf("Failed to write current_trigger file\n");
- goto error_free_buf_dir_name;
- }
-
- /* Setup ring buffer parameters */
- ret = write_sysfs_int("length", buf_dir_name, buf_len);
- if (ret < 0)
- goto error_free_buf_dir_name;
-
- /* Enable the buffer */
- ret = write_sysfs_int("ring_enable", buf_dir_name, 1);
- if (ret < 0)
- goto error_free_buf_dir_name;
-
- data = malloc(size_from_scanmode(num_vals, scan_ts)*buf_len);
- if (!data) {
- ret = -ENOMEM;
- goto error_free_buf_dir_name;
- }
-
- ret = asprintf(&buffer_access,
- "/dev/device%d:buffer0:access0",
- dev_num);
- if (ret < 0) {
- ret = -ENOMEM;
- goto error_free_data;
- }
-
- ret = asprintf(&buffer_event, "/dev/device%d:buffer0:event0", dev_num);
- if (ret < 0) {
- ret = -ENOMEM;
- goto error_free_data;
- }
- /* Attempt to open non blocking the access dev */
- fp = open(buffer_access, O_RDONLY | O_NONBLOCK);
- if (fp == -1) { /*If it isn't there make the node */
- printf("Failed to open %s\n", buffer_access);
- ret = -errno;
- goto error_free_buffer_event;
- }
- /* Attempt to open the event access dev (blocking this time) */
- fp_ev = fopen(buffer_event, "rb");
- if (fp_ev == NULL) {
- printf("Failed to open %s\n", buffer_event);
- ret = -errno;
- goto error_close_buffer_access;
- }
-
- /* Wait for events 10 times */
- for (j = 0; j < num_loops; j++) {
- read_size = fread(&dat, 1, sizeof(struct iio_event_data),
- fp_ev);
- switch (dat.id) {
- case IIO_EVENT_CODE_RING_100_FULL:
- toread = buf_len;
- break;
- case IIO_EVENT_CODE_RING_75_FULL:
- toread = buf_len*3/4;
- break;
- case IIO_EVENT_CODE_RING_50_FULL:
- toread = buf_len/2;
- break;
- default:
- printf("Unexpecteded event code\n");
- continue;
- }
- read_size = read(fp,
- data,
- toread*size_from_scanmode(num_vals, scan_ts));
- if (read_size == -EAGAIN) {
- printf("nothing available\n");
- continue;
- }
- scan_size = size_from_scanmode(num_vals, scan_ts);
- for (i = 0; i < read_size/scan_size; i++) {
- for (k = 0; k < num_vals; k++) {
- __s16 val = *(__s16 *)(&data[i*scan_size
- + (k)*2]);
- printf("%05f ", (float)val*gain);
- }
- printf(" %lld\n",
- *(__s64 *)(&data[(i + 1)
- *size_from_scanmode(num_vals,
- scan_ts)
- - sizeof(__s64)]));
- }
- }
-
- /* Stop the ring buffer */
- ret = write_sysfs_int("ring_enable", buf_dir_name, 0);
- if (ret < 0)
- goto error_close_buffer_event;
-
- /* Disconnect from the trigger - just write a dummy name.*/
- write_sysfs_string("trigger/current_trigger",
- dev_dir_name, "NULL");
-
-error_close_buffer_event:
- fclose(fp_ev);
-error_close_buffer_access:
- close(fp);
-error_free_data:
- free(data);
-error_free_buffer_access:
- free(buffer_access);
-error_free_buffer_event:
- free(buffer_event);
-error_free_buf_dir_name:
- free(buf_dir_name);
-error_free_triggername:
- free(trigger_name);
-error_free_dev_dir_name:
- free(dev_dir_name);
-error_ret:
- return ret;
-}
projects / mv-sheeva.git / blobdiff