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-rw-r--r--tools/iio/iio_generic_buffer.c708
1 files changed, 708 insertions, 0 deletions
diff --git a/tools/iio/iio_generic_buffer.c b/tools/iio/iio_generic_buffer.c
new file mode 100644
index 000000000..2fd10eab7
--- /dev/null
+++ b/tools/iio/iio_generic_buffer.c
@@ -0,0 +1,708 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Industrialio buffer test code.
+ *
+ * Copyright (c) 2008 Jonathan Cameron
+ *
+ * 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.
+ */
+
+#include <unistd.h>
+#include <stdlib.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 <stdbool.h>
+#include <signal.h>
+#include "iio_utils.h"
+
+/**
+ * enum autochan - state for the automatic channel enabling mechanism
+ */
+enum autochan {
+ AUTOCHANNELS_DISABLED,
+ AUTOCHANNELS_ENABLED,
+ AUTOCHANNELS_ACTIVE,
+};
+
+/**
+ * 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.
+ **/
+static unsigned int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
+{
+ unsigned int bytes = 0;
+ int i = 0, max = 0;
+ unsigned int misalignment;
+
+ while (i < num_channels) {
+ if (channels[i].bytes > max)
+ max = channels[i].bytes;
+ 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++;
+ }
+ /*
+ * We want the data in next sample to also be properly aligned so
+ * we'll add padding at the end if needed. Adding padding only
+ * works for channel data which size is 2^n bytes.
+ */
+ misalignment = bytes % max;
+ if (misalignment)
+ bytes += max - misalignment;
+
+ return bytes;
+}
+
+static void print1byte(uint8_t input, struct iio_channel_info *info)
+{
+ /*
+ * Shift before conversion to avoid sign extension
+ * of left aligned data
+ */
+ input >>= info->shift;
+ input &= info->mask;
+ if (info->is_signed) {
+ int8_t val = (int8_t)(input << (8 - info->bits_used)) >>
+ (8 - info->bits_used);
+ printf("%05f ", ((float)val + info->offset) * info->scale);
+ } else {
+ printf("%05f ", ((float)input + info->offset) * info->scale);
+ }
+}
+
+static void print2byte(uint16_t input, struct iio_channel_info *info)
+{
+ /* First swap if incorrect endian */
+ if (info->be)
+ input = be16toh(input);
+ else
+ input = le16toh(input);
+
+ /*
+ * Shift before conversion to avoid sign extension
+ * of left aligned data
+ */
+ input >>= info->shift;
+ input &= info->mask;
+ if (info->is_signed) {
+ int16_t val = (int16_t)(input << (16 - info->bits_used)) >>
+ (16 - info->bits_used);
+ printf("%05f ", ((float)val + info->offset) * info->scale);
+ } else {
+ printf("%05f ", ((float)input + info->offset) * info->scale);
+ }
+}
+
+static void print4byte(uint32_t input, struct iio_channel_info *info)
+{
+ /* First swap if incorrect endian */
+ if (info->be)
+ input = be32toh(input);
+ else
+ input = le32toh(input);
+
+ /*
+ * Shift before conversion to avoid sign extension
+ * of left aligned data
+ */
+ input >>= info->shift;
+ input &= info->mask;
+ if (info->is_signed) {
+ int32_t val = (int32_t)(input << (32 - info->bits_used)) >>
+ (32 - info->bits_used);
+ printf("%05f ", ((float)val + info->offset) * info->scale);
+ } else {
+ printf("%05f ", ((float)input + info->offset) * info->scale);
+ }
+}
+
+static void print8byte(uint64_t input, struct iio_channel_info *info)
+{
+ /* First swap if incorrect endian */
+ if (info->be)
+ input = be64toh(input);
+ else
+ input = le64toh(input);
+
+ /*
+ * Shift before conversion to avoid sign extension
+ * of left aligned data
+ */
+ input >>= info->shift;
+ input &= info->mask;
+ if (info->is_signed) {
+ int64_t val = (int64_t)(input << (64 - info->bits_used)) >>
+ (64 - info->bits_used);
+ /* special case for timestamp */
+ if (info->scale == 1.0f && info->offset == 0.0f)
+ printf("%" PRId64 " ", val);
+ else
+ printf("%05f ",
+ ((float)val + info->offset) * info->scale);
+ } else {
+ printf("%05f ", ((float)input + 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
+ **/
+static 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 1:
+ print1byte(*(uint8_t *)(data + channels[k].location),
+ &channels[k]);
+ break;
+ case 2:
+ print2byte(*(uint16_t *)(data + channels[k].location),
+ &channels[k]);
+ break;
+ case 4:
+ print4byte(*(uint32_t *)(data + channels[k].location),
+ &channels[k]);
+ break;
+ case 8:
+ print8byte(*(uint64_t *)(data + channels[k].location),
+ &channels[k]);
+ break;
+ default:
+ break;
+ }
+ printf("\n");
+}
+
+static int enable_disable_all_channels(char *dev_dir_name, int enable)
+{
+ const struct dirent *ent;
+ char scanelemdir[256];
+ DIR *dp;
+ int ret;
+
+ snprintf(scanelemdir, sizeof(scanelemdir),
+ FORMAT_SCAN_ELEMENTS_DIR, dev_dir_name);
+ scanelemdir[sizeof(scanelemdir)-1] = '\0';
+
+ dp = opendir(scanelemdir);
+ if (!dp) {
+ fprintf(stderr, "Enabling/disabling channels: can't open %s\n",
+ scanelemdir);
+ return -EIO;
+ }
+
+ ret = -ENOENT;
+ while (ent = readdir(dp), ent) {
+ if (iioutils_check_suffix(ent->d_name, "_en")) {
+ printf("%sabling: %s\n",
+ enable ? "En" : "Dis",
+ ent->d_name);
+ ret = write_sysfs_int(ent->d_name, scanelemdir,
+ enable);
+ if (ret < 0)
+ fprintf(stderr, "Failed to enable/disable %s\n",
+ ent->d_name);
+ }
+ }
+
+ if (closedir(dp) == -1) {
+ perror("Enabling/disabling channels: "
+ "Failed to close directory");
+ return -errno;
+ }
+ return 0;
+}
+
+static void print_usage(void)
+{
+ fprintf(stderr, "Usage: generic_buffer [options]...\n"
+ "Capture, convert and output data from IIO device buffer\n"
+ " -a Auto-activate all available channels\n"
+ " -A Force-activate ALL channels\n"
+ " -c <n> Do n conversions, or loop forever if n < 0\n"
+ " -e Disable wait for event (new data)\n"
+ " -g Use trigger-less mode\n"
+ " -l <n> Set buffer length to n samples\n"
+ " --device-name -n <name>\n"
+ " --device-num -N <num>\n"
+ " Set device by name or number (mandatory)\n"
+ " --trigger-name -t <name>\n"
+ " --trigger-num -T <num>\n"
+ " Set trigger by name or number\n"
+ " -w <n> Set delay between reads in us (event-less mode)\n");
+}
+
+static enum autochan autochannels = AUTOCHANNELS_DISABLED;
+static char *dev_dir_name = NULL;
+static char *buf_dir_name = NULL;
+static bool current_trigger_set = false;
+
+static void cleanup(void)
+{
+ int ret;
+
+ /* Disable trigger */
+ if (dev_dir_name && current_trigger_set) {
+ /* Disconnect the trigger - just write a dummy name. */
+ ret = write_sysfs_string("trigger/current_trigger",
+ dev_dir_name, "NULL");
+ if (ret < 0)
+ fprintf(stderr, "Failed to disable trigger: %s\n",
+ strerror(-ret));
+ current_trigger_set = false;
+ }
+
+ /* Disable buffer */
+ if (buf_dir_name) {
+ ret = write_sysfs_int("enable", buf_dir_name, 0);
+ if (ret < 0)
+ fprintf(stderr, "Failed to disable buffer: %s\n",
+ strerror(-ret));
+ }
+
+ /* Disable channels if auto-enabled */
+ if (dev_dir_name && autochannels == AUTOCHANNELS_ACTIVE) {
+ ret = enable_disable_all_channels(dev_dir_name, 0);
+ if (ret)
+ fprintf(stderr, "Failed to disable all channels\n");
+ autochannels = AUTOCHANNELS_DISABLED;
+ }
+}
+
+static void sig_handler(int signum)
+{
+ fprintf(stderr, "Caught signal %d\n", signum);
+ cleanup();
+ exit(-signum);
+}
+
+static void register_cleanup(void)
+{
+ struct sigaction sa = { .sa_handler = sig_handler };
+ const int signums[] = { SIGINT, SIGTERM, SIGABRT };
+ int ret, i;
+
+ for (i = 0; i < ARRAY_SIZE(signums); ++i) {
+ ret = sigaction(signums[i], &sa, NULL);
+ if (ret) {
+ perror("Failed to register signal handler");
+ exit(-1);
+ }
+ }
+}
+
+static const struct option longopts[] = {
+ { "device-name", 1, 0, 'n' },
+ { "device-num", 1, 0, 'N' },
+ { "trigger-name", 1, 0, 't' },
+ { "trigger-num", 1, 0, 'T' },
+ { },
+};
+
+int main(int argc, char **argv)
+{
+ long long num_loops = 2;
+ unsigned long timedelay = 1000000;
+ unsigned long buf_len = 128;
+
+ ssize_t i;
+ unsigned long long j;
+ unsigned long toread;
+ int ret, c;
+ int fp = -1;
+
+ int num_channels = 0;
+ char *trigger_name = NULL, *device_name = NULL;
+
+ char *data = NULL;
+ ssize_t read_size;
+ int dev_num = -1, trig_num = -1;
+ char *buffer_access = NULL;
+ unsigned int scan_size;
+ int noevents = 0;
+ int notrigger = 0;
+ char *dummy;
+ bool force_autochannels = false;
+
+ struct iio_channel_info *channels = NULL;
+
+ register_cleanup();
+
+ while ((c = getopt_long(argc, argv, "aAc:egl:n:N:t:T:w:?", longopts,
+ NULL)) != -1) {
+ switch (c) {
+ case 'a':
+ autochannels = AUTOCHANNELS_ENABLED;
+ break;
+ case 'A':
+ autochannels = AUTOCHANNELS_ENABLED;
+ force_autochannels = true;
+ break;
+ case 'c':
+ errno = 0;
+ num_loops = strtoll(optarg, &dummy, 10);
+ if (errno) {
+ ret = -errno;
+ goto error;
+ }
+
+ break;
+ case 'e':
+ noevents = 1;
+ break;
+ case 'g':
+ notrigger = 1;
+ break;
+ case 'l':
+ errno = 0;
+ buf_len = strtoul(optarg, &dummy, 10);
+ if (errno) {
+ ret = -errno;
+ goto error;
+ }
+
+ break;
+ case 'n':
+ device_name = strdup(optarg);
+ break;
+ case 'N':
+ errno = 0;
+ dev_num = strtoul(optarg, &dummy, 10);
+ if (errno) {
+ ret = -errno;
+ goto error;
+ }
+ break;
+ case 't':
+ trigger_name = strdup(optarg);
+ break;
+ case 'T':
+ errno = 0;
+ trig_num = strtoul(optarg, &dummy, 10);
+ if (errno)
+ return -errno;
+ break;
+ case 'w':
+ errno = 0;
+ timedelay = strtoul(optarg, &dummy, 10);
+ if (errno) {
+ ret = -errno;
+ goto error;
+ }
+ break;
+ case '?':
+ print_usage();
+ ret = -1;
+ goto error;
+ }
+ }
+
+ /* Find the device requested */
+ if (dev_num < 0 && !device_name) {
+ fprintf(stderr, "Device not set\n");
+ print_usage();
+ ret = -1;
+ goto error;
+ } else if (dev_num >= 0 && device_name) {
+ fprintf(stderr, "Only one of --device-num or --device-name needs to be set\n");
+ print_usage();
+ ret = -1;
+ goto error;
+ } else if (dev_num < 0) {
+ dev_num = find_type_by_name(device_name, "iio:device");
+ if (dev_num < 0) {
+ fprintf(stderr, "Failed to find the %s\n", device_name);
+ ret = dev_num;
+ goto error;
+ }
+ }
+ printf("iio device number being used is %d\n", dev_num);
+
+ ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
+ if (ret < 0)
+ return -ENOMEM;
+ /* Fetch device_name if specified by number */
+ if (!device_name) {
+ device_name = malloc(IIO_MAX_NAME_LENGTH);
+ if (!device_name) {
+ ret = -ENOMEM;
+ goto error;
+ }
+ ret = read_sysfs_string("name", dev_dir_name, device_name);
+ if (ret < 0) {
+ fprintf(stderr, "Failed to read name of device %d\n", dev_num);
+ goto error;
+ }
+ }
+
+ if (notrigger) {
+ printf("trigger-less mode selected\n");
+ } else if (trig_num >= 0) {
+ char *trig_dev_name;
+ ret = asprintf(&trig_dev_name, "%strigger%d", iio_dir, trig_num);
+ if (ret < 0) {
+ return -ENOMEM;
+ }
+ trigger_name = malloc(IIO_MAX_NAME_LENGTH);
+ ret = read_sysfs_string("name", trig_dev_name, trigger_name);
+ free(trig_dev_name);
+ if (ret < 0) {
+ fprintf(stderr, "Failed to read trigger%d name from\n", trig_num);
+ return ret;
+ }
+ printf("iio trigger number being used is %d\n", trig_num);
+ } else {
+ if (!trigger_name) {
+ /*
+ * 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;
+ }
+ }
+
+ /* Look for this "-devN" trigger */
+ trig_num = find_type_by_name(trigger_name, "trigger");
+ if (trig_num < 0) {
+ /* OK try the simpler "-trigger" suffix instead */
+ free(trigger_name);
+ ret = asprintf(&trigger_name,
+ "%s-trigger", device_name);
+ if (ret < 0) {
+ ret = -ENOMEM;
+ goto error;
+ }
+ }
+
+ trig_num = find_type_by_name(trigger_name, "trigger");
+ if (trig_num < 0) {
+ fprintf(stderr, "Failed to find the trigger %s\n",
+ trigger_name);
+ ret = trig_num;
+ goto error;
+ }
+
+ 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) {
+ fprintf(stderr, "Problem reading scan element information\n"
+ "diag %s\n", dev_dir_name);
+ goto error;
+ }
+ if (num_channels && autochannels == AUTOCHANNELS_ENABLED &&
+ !force_autochannels) {
+ fprintf(stderr, "Auto-channels selected but some channels "
+ "are already activated in sysfs\n");
+ fprintf(stderr, "Proceeding without activating any channels\n");
+ }
+
+ if ((!num_channels && autochannels == AUTOCHANNELS_ENABLED) ||
+ (autochannels == AUTOCHANNELS_ENABLED && force_autochannels)) {
+ fprintf(stderr, "Enabling all channels\n");
+
+ ret = enable_disable_all_channels(dev_dir_name, 1);
+ if (ret) {
+ fprintf(stderr, "Failed to enable all channels\n");
+ goto error;
+ }
+
+ /* This flags that we need to disable the channels again */
+ autochannels = AUTOCHANNELS_ACTIVE;
+
+ ret = build_channel_array(dev_dir_name, &channels,
+ &num_channels);
+ if (ret) {
+ fprintf(stderr, "Problem reading scan element "
+ "information\n"
+ "diag %s\n", dev_dir_name);
+ goto error;
+ }
+ if (!num_channels) {
+ fprintf(stderr, "Still no channels after "
+ "auto-enabling, giving up\n");
+ goto error;
+ }
+ }
+
+ if (!num_channels && autochannels == AUTOCHANNELS_DISABLED) {
+ fprintf(stderr,
+ "No channels are enabled, we have nothing to scan.\n");
+ fprintf(stderr, "Enable channels manually in "
+ FORMAT_SCAN_ELEMENTS_DIR
+ "/*_en or pass -a to autoenable channels and "
+ "try again.\n", dev_dir_name);
+ ret = -ENOENT;
+ goto error;
+ }
+
+ /*
+ * 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;
+ }
+
+ if (!notrigger) {
+ 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) {
+ fprintf(stderr,
+ "Failed to write current_trigger file\n");
+ goto error;
+ }
+ }
+
+ /* Setup ring buffer parameters */
+ ret = write_sysfs_int("length", buf_dir_name, buf_len);
+ if (ret < 0)
+ goto error;
+
+ /* Enable the buffer */
+ ret = write_sysfs_int("enable", buf_dir_name, 1);
+ if (ret < 0) {
+ fprintf(stderr,
+ "Failed to enable buffer: %s\n", strerror(-ret));
+ goto error;
+ }
+
+ scan_size = size_from_channelarray(channels, num_channels);
+
+ size_t total_buf_len = scan_size * buf_len;
+
+ if (scan_size > 0 && total_buf_len / scan_size != buf_len) {
+ ret = -EFAULT;
+ perror("Integer overflow happened when calculate scan_size * buf_len");
+ goto error;
+ }
+
+ data = malloc(total_buf_len);
+ if (!data) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ ret = asprintf(&buffer_access, "/dev/iio:device%d", dev_num);
+ if (ret < 0) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ /* Attempt to open non blocking the access dev */
+ fp = open(buffer_access, O_RDONLY | O_NONBLOCK);
+ if (fp == -1) { /* TODO: If it isn't there make the node */
+ ret = -errno;
+ fprintf(stderr, "Failed to open %s\n", buffer_access);
+ goto error;
+ }
+
+ for (j = 0; j < num_loops || num_loops < 0; j++) {
+ if (!noevents) {
+ struct pollfd pfd = {
+ .fd = fp,
+ .events = POLLIN,
+ };
+
+ ret = poll(&pfd, 1, -1);
+ if (ret < 0) {
+ ret = -errno;
+ goto error;
+ } else if (ret == 0) {
+ continue;
+ }
+
+ toread = buf_len;
+ } else {
+ usleep(timedelay);
+ toread = 64;
+ }
+
+ read_size = read(fp, data, toread * scan_size);
+ if (read_size < 0) {
+ if (errno == EAGAIN) {
+ fprintf(stderr, "nothing available\n");
+ continue;
+ } else {
+ break;
+ }
+ }
+ for (i = 0; i < read_size / scan_size; i++)
+ process_scan(data + scan_size * i, channels,
+ num_channels);
+ }
+
+error:
+ cleanup();
+
+ if (fp >= 0 && close(fp) == -1)
+ perror("Failed to close buffer");
+ free(buffer_access);
+ free(data);
+ free(buf_dir_name);
+ for (i = num_channels - 1; i >= 0; i--) {
+ free(channels[i].name);
+ free(channels[i].generic_name);
+ }
+ free(channels);
+ free(trigger_name);
+ free(device_name);
+ free(dev_dir_name);
+
+ return ret;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-03 18:37:26 +0000