mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
![Peter Meerwald](/assets/img/avatar_default.png)
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net> Acked-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
330 lines
7.9 KiB
C
330 lines
7.9 KiB
C
/* Industrialio buffer test code.
|
|
*
|
|
* 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.
|
|
* Reads the current buffer setup from sysfs and starts a short capture
|
|
* from the specified device, pretty printing the result after appropriate
|
|
* conversion.
|
|
*
|
|
* Command line parameters
|
|
* generic_buffer -n <device_name> -t <trigger_name>
|
|
* If trigger name is not specified the program assumes you want a dataready
|
|
* trigger associated with the device and goes looking for it.
|
|
*
|
|
*/
|
|
|
|
#define _GNU_SOURCE
|
|
|
|
#include <unistd.h>
|
|
#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 <string.h>
|
|
#include <poll.h>
|
|
#include <endian.h>
|
|
#include <getopt.h>
|
|
#include <inttypes.h>
|
|
#include "iio_utils.h"
|
|
|
|
/**
|
|
* size_from_channelarray() - calculate the storage size of a scan
|
|
* @channels: the channel info array
|
|
* @num_channels: number of channels
|
|
*
|
|
* Has the side effect of filling the channels[i].location values used
|
|
* in processing the buffer output.
|
|
**/
|
|
int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
|
|
{
|
|
int bytes = 0;
|
|
int i = 0;
|
|
while (i < num_channels) {
|
|
if (bytes % channels[i].bytes == 0)
|
|
channels[i].location = bytes;
|
|
else
|
|
channels[i].location = bytes - bytes%channels[i].bytes
|
|
+ channels[i].bytes;
|
|
bytes = channels[i].location + channels[i].bytes;
|
|
i++;
|
|
}
|
|
return bytes;
|
|
}
|
|
|
|
void print2byte(int input, struct iio_channel_info *info)
|
|
{
|
|
/* First swap if incorrect endian */
|
|
if (info->be)
|
|
input = be16toh((uint16_t)input);
|
|
else
|
|
input = le16toh((uint16_t)input);
|
|
|
|
/*
|
|
* Shift before conversion to avoid sign extension
|
|
* of left aligned data
|
|
*/
|
|
input = input >> info->shift;
|
|
if (info->is_signed) {
|
|
int16_t val = input;
|
|
val &= (1 << info->bits_used) - 1;
|
|
val = (int16_t)(val << (16 - info->bits_used)) >>
|
|
(16 - info->bits_used);
|
|
printf("%05f ", ((float)val + info->offset)*info->scale);
|
|
} else {
|
|
uint16_t val = input;
|
|
val &= (1 << info->bits_used) - 1;
|
|
printf("%05f ", ((float)val + info->offset)*info->scale);
|
|
}
|
|
}
|
|
/**
|
|
* process_scan() - print out the values in SI units
|
|
* @data: pointer to the start of the scan
|
|
* @channels: information about the channels. Note
|
|
* size_from_channelarray must have been called first to fill the
|
|
* location offsets.
|
|
* @num_channels: number of channels
|
|
**/
|
|
void process_scan(char *data,
|
|
struct iio_channel_info *channels,
|
|
int num_channels)
|
|
{
|
|
int k;
|
|
for (k = 0; k < num_channels; k++)
|
|
switch (channels[k].bytes) {
|
|
/* only a few cases implemented so far */
|
|
case 2:
|
|
print2byte(*(uint16_t *)(data + channels[k].location),
|
|
&channels[k]);
|
|
break;
|
|
case 8:
|
|
if (channels[k].is_signed) {
|
|
int64_t val = *(int64_t *)
|
|
(data +
|
|
channels[k].location);
|
|
if ((val >> channels[k].bits_used) & 1)
|
|
val = (val & channels[k].mask) |
|
|
~channels[k].mask;
|
|
/* special case for timestamp */
|
|
if (channels[k].scale == 1.0f &&
|
|
channels[k].offset == 0.0f)
|
|
printf("%" PRId64 " ", val);
|
|
else
|
|
printf("%05f ", ((float)val +
|
|
channels[k].offset)*
|
|
channels[k].scale);
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
printf("\n");
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
unsigned long num_loops = 2;
|
|
unsigned long timedelay = 1000000;
|
|
unsigned long buf_len = 128;
|
|
|
|
int ret, c, i, j, toread;
|
|
int fp;
|
|
|
|
int num_channels;
|
|
char *trigger_name = NULL, *device_name = NULL;
|
|
char *dev_dir_name, *buf_dir_name;
|
|
|
|
int datardytrigger = 1;
|
|
char *data;
|
|
ssize_t read_size;
|
|
int dev_num, trig_num;
|
|
char *buffer_access;
|
|
int scan_size;
|
|
int noevents = 0;
|
|
char *dummy;
|
|
|
|
struct iio_channel_info *channels;
|
|
|
|
while ((c = getopt(argc, argv, "l:w:c:et:n:")) != -1) {
|
|
switch (c) {
|
|
case 'n':
|
|
device_name = optarg;
|
|
break;
|
|
case 't':
|
|
trigger_name = optarg;
|
|
datardytrigger = 0;
|
|
break;
|
|
case 'e':
|
|
noevents = 1;
|
|
break;
|
|
case 'c':
|
|
num_loops = strtoul(optarg, &dummy, 10);
|
|
break;
|
|
case 'w':
|
|
timedelay = strtoul(optarg, &dummy, 10);
|
|
break;
|
|
case 'l':
|
|
buf_len = strtoul(optarg, &dummy, 10);
|
|
break;
|
|
case '?':
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
if (device_name == NULL)
|
|
return -1;
|
|
|
|
/* Find the device requested */
|
|
dev_num = find_type_by_name(device_name, "iio: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, "%siio:device%d", iio_dir, dev_num);
|
|
if (trigger_name == NULL) {
|
|
/*
|
|
* Build the trigger name. If it is device associated its
|
|
* name is <device_name>_dev[n] where n matches the device
|
|
* number found above
|
|
*/
|
|
ret = asprintf(&trigger_name,
|
|
"%s-dev%d", device_name, dev_num);
|
|
if (ret < 0) {
|
|
ret = -ENOMEM;
|
|
goto error_ret;
|
|
}
|
|
}
|
|
|
|
/* Verify the trigger exists */
|
|
trig_num = find_type_by_name(trigger_name, "trigger");
|
|
if (trig_num < 0) {
|
|
printf("Failed to find the trigger %s\n", trigger_name);
|
|
ret = -ENODEV;
|
|
goto error_free_triggername;
|
|
}
|
|
printf("iio trigger number being used is %d\n", trig_num);
|
|
|
|
/*
|
|
* Parse the files in scan_elements to identify what channels are
|
|
* present
|
|
*/
|
|
ret = build_channel_array(dev_dir_name, &channels, &num_channels);
|
|
if (ret) {
|
|
printf("Problem reading scan element information\n");
|
|
printf("diag %s\n", dev_dir_name);
|
|
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,
|
|
"%siio:device%d/buffer", iio_dir, dev_num);
|
|
if (ret < 0) {
|
|
ret = -ENOMEM;
|
|
goto error_free_triggername;
|
|
}
|
|
printf("%s %s\n", dev_dir_name, trigger_name);
|
|
/* Set the device trigger to be the data ready 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("enable", buf_dir_name, 1);
|
|
if (ret < 0)
|
|
goto error_free_buf_dir_name;
|
|
scan_size = size_from_channelarray(channels, num_channels);
|
|
data = malloc(scan_size*buf_len);
|
|
if (!data) {
|
|
ret = -ENOMEM;
|
|
goto error_free_buf_dir_name;
|
|
}
|
|
|
|
ret = asprintf(&buffer_access, "/dev/iio:device%d", 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_access;
|
|
}
|
|
|
|
/* Wait for events 10 times */
|
|
for (j = 0; j < num_loops; j++) {
|
|
if (!noevents) {
|
|
struct pollfd pfd = {
|
|
.fd = fp,
|
|
.events = POLLIN,
|
|
};
|
|
|
|
poll(&pfd, 1, -1);
|
|
toread = buf_len;
|
|
|
|
} else {
|
|
usleep(timedelay);
|
|
toread = 64;
|
|
}
|
|
|
|
read_size = read(fp,
|
|
data,
|
|
toread*scan_size);
|
|
if (read_size == -EAGAIN) {
|
|
printf("nothing available\n");
|
|
continue;
|
|
}
|
|
for (i = 0; i < read_size/scan_size; i++)
|
|
process_scan(data + scan_size*i,
|
|
channels,
|
|
num_channels);
|
|
}
|
|
|
|
/* Stop the buffer */
|
|
ret = write_sysfs_int("enable", buf_dir_name, 0);
|
|
if (ret < 0)
|
|
goto error_close_buffer_access;
|
|
|
|
/* Disconnect the trigger - just write a dummy name. */
|
|
write_sysfs_string("trigger/current_trigger",
|
|
dev_dir_name, "NULL");
|
|
|
|
error_close_buffer_access:
|
|
close(fp);
|
|
error_free_data:
|
|
free(data);
|
|
error_free_buffer_access:
|
|
free(buffer_access);
|
|
error_free_buf_dir_name:
|
|
free(buf_dir_name);
|
|
error_free_triggername:
|
|
if (datardytrigger)
|
|
free(trigger_name);
|
|
error_ret:
|
|
return ret;
|
|
}
|