1 files changed, 682 insertions, 0 deletions

diff --git a/tools/iio/iio_generic_buffer.c b/tools/iio/iio_generic_buffer.c
new file mode 100644
index 0000000..0e8a1f7
--- /dev/null
+++ b/tools/iio/iio_generic_buffer.c
@@ -0,0 +1,682 @@
+/* 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.
+ *
+ */
+
+#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.
+ **/
+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 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);
+	}
+}
+
+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);
+	}
+}
+
+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);
+	}
+}
+
+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
+ **/
+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;
+}
+
+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"
+		"  -c <n>     Do n conversions\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");
+}
+
+enum autochan autochannels = AUTOCHANNELS_DISABLED;
+char *dev_dir_name = NULL;
+char *buf_dir_name = NULL;
+bool current_trigger_set = false;
+
+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;
+	}
+}
+
+void sig_handler(int signum)
+{
+	fprintf(stderr, "Caught signal %d\n", signum);
+	cleanup();
+	exit(-signum);
+}
+
+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)
+{
+	unsigned long num_loops = 2;
+	unsigned long timedelay = 1000000;
+	unsigned long buf_len = 128;
+
+	int ret, c, i, j, toread;
+	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;
+	int scan_size;
+	int noevents = 0;
+	int notrigger = 0;
+	char *dummy;
+
+	struct iio_channel_info *channels;
+
+	register_cleanup();
+
+	while ((c = getopt_long(argc, argv, "ac:egl:n:N:t:T:w:", longopts, NULL)) != -1) {
+		switch (c) {
+		case 'a':
+			autochannels = AUTOCHANNELS_ENABLED;
+			break;
+		case 'c':
+			errno = 0;
+			num_loops = strtoul(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");
+	} 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) {
+		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) {
+		fprintf(stderr,
+			"No channels are enabled, 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);
+	data = malloc(scan_size * 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; 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;
+}