Initial import

1 files changed, 359 insertions, 0 deletions

diff --git a/tools/iio/generic_buffer.c b/tools/iio/generic_buffer.c
new file mode 100644
index 000000000..f805493be
--- /dev/null
+++ b/tools/iio/generic_buffer.c
@@ -0,0 +1,359 @@
+/* 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 "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 >>= 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 4:
+			if (!channels[k].is_signed) {
+				uint32_t val = *(uint32_t *)
+					(data + channels[k].location);
+				printf("%05f ", ((float)val +
+						 channels[k].offset)*
+				       channels[k].scale);
+
+			}
+			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;
+	int notrigger = 0;
+	char *dummy;
+
+	struct iio_channel_info *channels;
+
+	while ((c = getopt(argc, argv, "l:w:c:et:n:g")) != -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 'g':
+			notrigger = 1;
+			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 (!notrigger) {
+		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);
+	} else
+		printf("trigger-less mode selected\n");
+
+	/*
+	 * 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;
+	}
+
+	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) {
+			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 < 0) {
+			if (errno == -EAGAIN) {
+				printf("nothing available\n");
+				continue;
+			} else
+				break;
+		}
+		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;
+
+	if (!notrigger)
+		/* 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;
+}