6 files changed, 863 insertions, 362 deletions

diff --git a/kernel/tools/iio/Makefile b/kernel/tools/iio/Makefile
index bf7ae6d66..3a7a54f59 100644
--- a/kernel/tools/iio/Makefile
+++ b/kernel/tools/iio/Makefile
@@ -1,5 +1,5 @@
-CC = gcc
-CFLAGS = -Wall -g -D_GNU_SOURCE
+CC = $(CROSS_COMPILE)gcc
+CFLAGS += -Wall -g -D_GNU_SOURCE
 
 all: iio_event_monitor lsiio generic_buffer
 
diff --git a/kernel/tools/iio/generic_buffer.c b/kernel/tools/iio/generic_buffer.c
index f805493be..01c4f6780 100644
--- a/kernel/tools/iio/generic_buffer.c
+++ b/kernel/tools/iio/generic_buffer.c
@@ -51,47 +51,113 @@ int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
 		if (bytes % channels[i].bytes == 0)
 			channels[i].location = bytes;
 		else
-			channels[i].location = bytes - bytes%channels[i].bytes
-				+ channels[i].bytes;
+			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)
+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((uint16_t)input);
+		input = be16toh(input);
 	else
-		input = le16toh((uint16_t)input);
+		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 = input;
+		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);
 
-		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);
+	/*
+	 * 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 {
-		uint16_t val = input;
+		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);
 
-		val &= (1 << info->bits_used) - 1;
-		printf("%05f ", ((float)val + info->offset)*info->scale);
+	/*
+	 * 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.
+ * @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,
@@ -103,37 +169,21 @@ void process_scan(char *data,
 	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:
-			if (!channels[k].is_signed) {
-				uint32_t val = *(uint32_t *)
-					(data + channels[k].location);
-				printf("%05f ", ((float)val +
-						 channels[k].offset)*
-				       channels[k].scale);
-
-			}
+			print4byte(*(uint32_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);
-			}
+			print8byte(*(uint64_t *)(data + channels[k].location),
+				   &channels[k]);
 			break;
 		default:
 			break;
@@ -141,6 +191,19 @@ void process_scan(char *data,
 	printf("\n");
 }
 
+void print_usage(void)
+{
+	fprintf(stderr, "Usage: generic_buffer [options]...\n"
+		"Capture, convert and output data from IIO device buffer\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"
+		"  -n <name>  Set device name (mandatory)\n"
+		"  -t <name>  Set trigger name\n"
+		"  -w <n>     Set delay between reads in us (event-less mode)\n");
+}
+
 int main(int argc, char **argv)
 {
 	unsigned long num_loops = 2;
@@ -166,8 +229,28 @@ int main(int argc, char **argv)
 
 	struct iio_channel_info *channels;
 
-	while ((c = getopt(argc, argv, "l:w:c:et:n:g")) != -1) {
+	while ((c = getopt(argc, argv, "c:egl:n:t:w:")) != -1) {
 		switch (c) {
+		case 'c':
+			errno = 0;
+			num_loops = strtoul(optarg, &dummy, 10);
+			if (errno)
+				return -errno;
+
+			break;
+		case 'e':
+			noevents = 1;
+			break;
+		case 'g':
+			notrigger = 1;
+			break;
+		case 'l':
+			errno = 0;
+			buf_len = strtoul(optarg, &dummy, 10);
+			if (errno)
+				return -errno;
+
+			break;
 		case 'n':
 			device_name = optarg;
 			break;
@@ -175,42 +258,39 @@ int main(int argc, char **argv)
 			trigger_name = optarg;
 			datardytrigger = 0;
 			break;
-		case 'e':
-			noevents = 1;
-			break;
-		case 'c':
-			num_loops = strtoul(optarg, &dummy, 10);
-			break;
 		case 'w':
+			errno = 0;
 			timedelay = strtoul(optarg, &dummy, 10);
-			break;
-		case 'l':
-			buf_len = strtoul(optarg, &dummy, 10);
-			break;
-		case 'g':
-			notrigger = 1;
+			if (errno)
+				return -errno;
 			break;
 		case '?':
+			print_usage();
 			return -1;
 		}
 	}
 
-	if (device_name == NULL)
+	if (!device_name) {
+		fprintf(stderr, "Device name not set\n");
+		print_usage();
 		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;
+		fprintf(stderr, "Failed to find the %s\n", device_name);
+		return dev_num;
 	}
+
 	printf("iio device number being used is %d\n", dev_num);
 
-	asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
+	ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
+	if (ret < 0)
+		return -ENOMEM;
 
 	if (!notrigger) {
-		if (trigger_name == NULL) {
+		if (!trigger_name) {
 			/*
 			 * Build the trigger name. If it is device associated
 			 * its name is <device_name>_dev[n] where n matches
@@ -220,20 +300,23 @@ int main(int argc, char **argv)
 				       "%s-dev%d", device_name, dev_num);
 			if (ret < 0) {
 				ret = -ENOMEM;
-				goto error_ret;
+				goto error_free_dev_dir_name;
 			}
 		}
 
 		/* 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;
+			fprintf(stderr, "Failed to find the trigger %s\n",
+				trigger_name);
+			ret = trig_num;
 			goto error_free_triggername;
 		}
+
 		printf("iio trigger number being used is %d\n", trig_num);
-	} else
+	} else {
 		printf("trigger-less mode selected\n");
+	}
 
 	/*
 	 * Parse the files in scan_elements to identify what channels are
@@ -241,8 +324,17 @@ int main(int argc, char **argv)
 	 */
 	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);
+		fprintf(stderr, "Problem reading scan element information\n"
+			"diag %s\n", dev_dir_name);
+		goto error_free_triggername;
+	}
+	if (!num_channels) {
+		fprintf(stderr,
+			"No channels are enabled, we have nothing to scan.\n");
+		fprintf(stderr, "Enable channels manually in "
+			FORMAT_SCAN_ELEMENTS_DIR
+			"/*_en and try again.\n", dev_dir_name);
+		ret = -ENOENT;
 		goto error_free_triggername;
 	}
 
@@ -255,18 +347,21 @@ int main(int argc, char **argv)
 		       "%siio:device%d/buffer", iio_dir, dev_num);
 	if (ret < 0) {
 		ret = -ENOMEM;
-		goto error_free_triggername;
+		goto error_free_channels;
 	}
 
 	if (!notrigger) {
 		printf("%s %s\n", dev_dir_name, trigger_name);
-		/* Set the device trigger to be the data ready trigger found
-		 * above */
+		/*
+		 * 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");
+			fprintf(stderr,
+				"Failed to write current_trigger file\n");
 			goto error_free_buf_dir_name;
 		}
 	}
@@ -278,10 +373,14 @@ int main(int argc, char **argv)
 
 	/* Enable the buffer */
 	ret = write_sysfs_int("enable", buf_dir_name, 1);
-	if (ret < 0)
+	if (ret < 0) {
+		fprintf(stderr,
+			"Failed to enable buffer: %s\n", strerror(-ret));
 		goto error_free_buf_dir_name;
+	}
+
 	scan_size = size_from_channelarray(channels, num_channels);
-	data = malloc(scan_size*buf_len);
+	data = malloc(scan_size * buf_len);
 	if (!data) {
 		ret = -ENOMEM;
 		goto error_free_buf_dir_name;
@@ -295,13 +394,12 @@ int main(int argc, char **argv)
 
 	/* 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);
+	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_free_buffer_access;
 	}
 
-	/* Wait for events 10 times */
 	for (j = 0; j < num_loops; j++) {
 		if (!noevents) {
 			struct pollfd pfd = {
@@ -309,27 +407,31 @@ int main(int argc, char **argv)
 				.events = POLLIN,
 			};
 
-			poll(&pfd, 1, -1);
-			toread = buf_len;
+			ret = poll(&pfd, 1, -1);
+			if (ret < 0) {
+				ret = -errno;
+				goto error_close_buffer_access;
+			} else if (ret == 0) {
+				continue;
+			}
 
+			toread = buf_len;
 		} else {
 			usleep(timedelay);
 			toread = 64;
 		}
 
-		read_size = read(fp,
-				 data,
-				 toread*scan_size);
+		read_size = read(fp, data, toread * scan_size);
 		if (read_size < 0) {
-			if (errno == -EAGAIN) {
-				printf("nothing available\n");
+			if (errno == EAGAIN) {
+				fprintf(stderr, "nothing available\n");
 				continue;
-			} else
+			} else {
 				break;
+			}
 		}
-		for (i = 0; i < read_size/scan_size; i++)
-			process_scan(data + scan_size*i,
-				     channels,
+		for (i = 0; i < read_size / scan_size; i++)
+			process_scan(data + scan_size * i, channels,
 				     num_channels);
 	}
 
@@ -340,20 +442,34 @@ int main(int argc, char **argv)
 
 	if (!notrigger)
 		/* Disconnect the trigger - just write a dummy name. */
-		write_sysfs_string("trigger/current_trigger",
-				   dev_dir_name, "NULL");
+		ret = write_sysfs_string("trigger/current_trigger",
+					 dev_dir_name, "NULL");
+		if (ret < 0)
+			fprintf(stderr, "Failed to write to %s\n",
+				dev_dir_name);
 
 error_close_buffer_access:
-	close(fp);
-error_free_data:
-	free(data);
+	if (close(fp) == -1)
+		perror("Failed to close buffer");
+
 error_free_buffer_access:
 	free(buffer_access);
+error_free_data:
+	free(data);
 error_free_buf_dir_name:
 	free(buf_dir_name);
+error_free_channels:
+	for (i = num_channels - 1; i >= 0; i--) {
+		free(channels[i].name);
+		free(channels[i].generic_name);
+	}
+	free(channels);
 error_free_triggername:
 	if (datardytrigger)
 		free(trigger_name);
-error_ret:
+
+error_free_dev_dir_name:
+	free(dev_dir_name);
+
 	return ret;
 }
diff --git a/kernel/tools/iio/iio_event_monitor.c b/kernel/tools/iio/iio_event_monitor.c
index 427c271ac..d51eb0420 100644
--- a/kernel/tools/iio/iio_event_monitor.c
+++ b/kernel/tools/iio/iio_event_monitor.c
@@ -13,7 +13,6 @@
  *
  * Usage:
  *	iio_event_monitor <device_name>
- *
  */
 
 #include <unistd.h>
@@ -51,6 +50,9 @@ static const char * const iio_chan_type_name_spec[] = {
 	[IIO_HUMIDITYRELATIVE] = "humidityrelative",
 	[IIO_ACTIVITY] = "activity",
 	[IIO_STEPS] = "steps",
+	[IIO_ENERGY] = "energy",
+	[IIO_DISTANCE] = "distance",
+	[IIO_VELOCITY] = "velocity",
 };
 
 static const char * const iio_ev_type_text[] = {
@@ -99,6 +101,7 @@ static const char * const iio_modifier_names[] = {
 	[IIO_MOD_JOGGING] = "jogging",
 	[IIO_MOD_WALKING] = "walking",
 	[IIO_MOD_STILL] = "still",
+	[IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z] = "sqrt(x^2+y^2+z^2)",
 };
 
 static bool event_is_known(struct iio_event_data *event)
@@ -130,6 +133,9 @@ static bool event_is_known(struct iio_event_data *event)
 	case IIO_HUMIDITYRELATIVE:
 	case IIO_ACTIVITY:
 	case IIO_STEPS:
+	case IIO_ENERGY:
+	case IIO_DISTANCE:
+	case IIO_VELOCITY:
 		break;
 	default:
 		return false;
@@ -167,6 +173,7 @@ static bool event_is_known(struct iio_event_data *event)
 	case IIO_MOD_JOGGING:
 	case IIO_MOD_WALKING:
 	case IIO_MOD_STILL:
+	case IIO_MOD_ROOT_SUM_SQUARED_X_Y_Z:
 		break;
 	default:
 		return false;
@@ -208,31 +215,29 @@ static void print_event(struct iio_event_data *event)
 	bool diff = IIO_EVENT_CODE_EXTRACT_DIFF(event->id);
 
 	if (!event_is_known(event)) {
-		printf("Unknown event: time: %lld, id: %llx\n",
-				event->timestamp, event->id);
+		fprintf(stderr, "Unknown event: time: %lld, id: %llx\n",
+			event->timestamp, event->id);
+
 		return;
 	}
 
-	printf("Event: time: %lld, ", event->timestamp);
+	printf("Event: time: %lld, type: %s", event->timestamp,
+	       iio_chan_type_name_spec[type]);
 
-	if (mod != IIO_NO_MOD) {
-		printf("type: %s(%s), ",
-			iio_chan_type_name_spec[type],
-			iio_modifier_names[mod]);
-	} else {
-		printf("type: %s, ",
-			iio_chan_type_name_spec[type]);
-	}
+	if (mod != IIO_NO_MOD)
+		printf("(%s)", iio_modifier_names[mod]);
 
-	if (diff && chan >= 0 && chan2 >= 0)
-		printf("channel: %d-%d, ", chan, chan2);
-	else if (chan >= 0)
-		printf("channel: %d, ", chan);
+	if (chan >= 0) {
+		printf(", channel: %d", chan);
+		if (diff && chan2 >= 0)
+			printf("-%d", chan2);
+	}
 
-	printf("evtype: %s", iio_ev_type_text[ev_type]);
+	printf(", evtype: %s", iio_ev_type_text[ev_type]);
 
 	if (dir != IIO_EV_DIR_NONE)
 		printf(", direction: %s", iio_ev_dir_text[dir]);
+
 	printf("\n");
 }
 
@@ -246,7 +251,7 @@ int main(int argc, char **argv)
 	int fd, event_fd;
 
 	if (argc <= 1) {
-		printf("Usage: %s <device_name>\n", argv[0]);
+		fprintf(stderr, "Usage: %s <device_name>\n", argv[0]);
 		return -1;
 	}
 
@@ -255,31 +260,42 @@ int main(int argc, char **argv)
 	dev_num = find_type_by_name(device_name, "iio:device");
 	if (dev_num >= 0) {
 		printf("Found IIO device with name %s with device number %d\n",
-			device_name, dev_num);
+		       device_name, dev_num);
 		ret = asprintf(&chrdev_name, "/dev/iio:device%d", dev_num);
-		if (ret < 0) {
-			ret = -ENOMEM;
-			goto error_ret;
-		}
+		if (ret < 0)
+			return -ENOMEM;
 	} else {
-		/* If we can't find a IIO device by name assume device_name is a
-		   IIO chrdev */
+		/*
+		 * If we can't find an IIO device by name assume device_name is
+		 * an IIO chrdev
+		 */
 		chrdev_name = strdup(device_name);
+		if (!chrdev_name)
+			return -ENOMEM;
 	}
 
 	fd = open(chrdev_name, 0);
 	if (fd == -1) {
-		fprintf(stdout, "Failed to open %s\n", chrdev_name);
 		ret = -errno;
+		fprintf(stderr, "Failed to open %s\n", chrdev_name);
 		goto error_free_chrdev_name;
 	}
 
 	ret = ioctl(fd, IIO_GET_EVENT_FD_IOCTL, &event_fd);
+	if (ret == -1 || event_fd == -1) {
+		ret = -errno;
+		if (ret == -ENODEV)
+			fprintf(stderr,
+				"This device does not support events\n");
+		else
+			fprintf(stderr, "Failed to retrieve event fd\n");
+		if (close(fd) == -1)
+			perror("Failed to close character device file");
 
-	close(fd);
+		goto error_free_chrdev_name;
+	}
 
-	if (ret == -1 || event_fd == -1) {
-		fprintf(stdout, "Failed to retrieve event fd\n");
+	if (close(fd) == -1)  {
 		ret = -errno;
 		goto error_free_chrdev_name;
 	}
@@ -288,21 +304,29 @@ int main(int argc, char **argv)
 		ret = read(event_fd, &event, sizeof(event));
 		if (ret == -1) {
 			if (errno == EAGAIN) {
-				printf("nothing available\n");
+				fprintf(stderr, "nothing available\n");
 				continue;
 			} else {
-				perror("Failed to read event from device");
 				ret = -errno;
+				perror("Failed to read event from device");
 				break;
 			}
 		}
 
+		if (ret != sizeof(event)) {
+			fprintf(stderr, "Reading event failed!\n");
+			ret = -EIO;
+			break;
+		}
+
 		print_event(&event);
 	}
 
-	close(event_fd);
+	if (close(event_fd) == -1)
+		perror("Failed to close event file");
+
 error_free_chrdev_name:
 	free(chrdev_name);
-error_ret:
+
 	return ret;
 }
diff --git a/kernel/tools/iio/iio_utils.c b/kernel/tools/iio/iio_utils.c
index 6f6452167..5eb6793f3 100644
--- a/kernel/tools/iio/iio_utils.c
+++ b/kernel/tools/iio/iio_utils.c
@@ -6,9 +6,6 @@
  * under the terms of the GNU General Public License version 2 as published by
  * the Free Software Foundation.
  */
-#ifndef _IIO_UTILS_H
-#define _IIO_UTILS_H
-
 #include <string.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -29,16 +26,17 @@ static char * const iio_direction[] = {
  * iioutils_break_up_name() - extract generic name from full channel name
  * @full_name: the full channel name
  * @generic_name: the output generic channel name
+ *
+ * Returns 0 on success, or a negative error code if string extraction failed.
  **/
-int iioutils_break_up_name(const char *full_name,
-				  char **generic_name)
+int iioutils_break_up_name(const char *full_name, char **generic_name)
 {
 	char *current;
 	char *w, *r;
 	char *working, *prefix = "";
-	int i;
+	int i, ret;
 
-	for (i = 0; i < sizeof(iio_direction) / sizeof(iio_direction[0]); i++)
+	for (i = 0; i < ARRAY_SIZE(iio_direction); i++)
 		if (!strncmp(full_name, iio_direction[i],
 			     strlen(iio_direction[i]))) {
 			prefix = iio_direction[i];
@@ -46,7 +44,14 @@ int iioutils_break_up_name(const char *full_name,
 		}
 
 	current = strdup(full_name + strlen(prefix) + 1);
+	if (!current)
+		return -ENOMEM;
+
 	working = strtok(current, "_\0");
+	if (!working) {
+		free(current);
+		return -EINVAL;
+	}
 
 	w = working;
 	r = working;
@@ -56,34 +61,34 @@ int iioutils_break_up_name(const char *full_name,
 			*w = *r;
 			w++;
 		}
+
 		r++;
 	}
 	*w = '\0';
-	asprintf(generic_name, "%s_%s", prefix, working);
+	ret = asprintf(generic_name, "%s_%s", prefix, working);
 	free(current);
 
-	return 0;
+	return (ret == -1) ? -ENOMEM : 0;
 }
 
 /**
  * iioutils_get_type() - find and process _type attribute data
  * @is_signed: output whether channel is signed
  * @bytes: output how many bytes the channel storage occupies
+ * @bits_used: output number of valid bits of data
+ * @shift: output amount of bits to shift right data before applying bit mask
  * @mask: output a bit mask for the raw data
- * @be: big endian
- * @device_dir: the iio device directory
+ * @be: output if data in big endian
+ * @device_dir: the IIO device directory
  * @name: the channel name
  * @generic_name: the channel type name
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
  **/
-int iioutils_get_type(unsigned *is_signed,
-			     unsigned *bytes,
-			     unsigned *bits_used,
-			     unsigned *shift,
-			     uint64_t *mask,
-			     unsigned *be,
-			     const char *device_dir,
-			     const char *name,
-			     const char *generic_name)
+int iioutils_get_type(unsigned *is_signed, unsigned *bytes, unsigned *bits_used,
+		      unsigned *shift, uint64_t *mask, unsigned *be,
+		      const char *device_dir, const char *name,
+		      const char *generic_name)
 {
 	FILE *sysfsfp;
 	int ret;
@@ -94,10 +99,9 @@ int iioutils_get_type(unsigned *is_signed,
 	const struct dirent *ent;
 
 	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
+	if (ret < 0)
+		return -ENOMEM;
+
 	ret = asprintf(&builtname, FORMAT_TYPE_FILE, name);
 	if (ret < 0) {
 		ret = -ENOMEM;
@@ -110,11 +114,13 @@ int iioutils_get_type(unsigned *is_signed,
 	}
 
 	dp = opendir(scan_el_dir);
-	if (dp == NULL) {
+	if (!dp) {
 		ret = -errno;
 		goto error_free_builtname_generic;
 	}
-	while (ent = readdir(dp), ent != NULL)
+
+	ret = -ENOENT;
+	while (ent = readdir(dp), ent)
 		/*
 		 * Do we allow devices to override a generic name with
 		 * a specific one?
@@ -127,10 +133,12 @@ int iioutils_get_type(unsigned *is_signed,
 				ret = -ENOMEM;
 				goto error_closedir;
 			}
+
 			sysfsfp = fopen(filename, "r");
-			if (sysfsfp == NULL) {
-				printf("failed to open %s\n", filename);
+			if (!sysfsfp) {
 				ret = -errno;
+				fprintf(stderr, "failed to open %s\n",
+					filename);
 				goto error_free_filename;
 			}
 
@@ -141,49 +149,73 @@ int iioutils_get_type(unsigned *is_signed,
 				     bits_used,
 				     &padint, shift);
 			if (ret < 0) {
-				printf("failed to pass scan type description\n");
 				ret = -errno;
+				fprintf(stderr,
+					"failed to pass scan type description\n");
+				goto error_close_sysfsfp;
+			} else if (ret != 5) {
+				ret = -EIO;
+				fprintf(stderr,
+					"scan type description didn't match\n");
 				goto error_close_sysfsfp;
 			}
+
 			*be = (endianchar == 'b');
 			*bytes = padint / 8;
 			if (*bits_used == 64)
 				*mask = ~0;
 			else
-				*mask = (1 << *bits_used) - 1;
-			if (signchar == 's')
-				*is_signed = 1;
-			else
-				*is_signed = 0;
-			fclose(sysfsfp);
-			free(filename);
+				*mask = (1ULL << *bits_used) - 1;
+
+			*is_signed = (signchar == 's');
+			if (fclose(sysfsfp)) {
+				ret = -errno;
+				fprintf(stderr, "Failed to close %s\n",
+					filename);
+				goto error_free_filename;
+			}
 
-			filename = 0;
 			sysfsfp = 0;
+			free(filename);
+			filename = 0;
 		}
+
 error_close_sysfsfp:
 	if (sysfsfp)
-		fclose(sysfsfp);
+		if (fclose(sysfsfp))
+			perror("iioutils_get_type(): Failed to close file");
+
 error_free_filename:
 	if (filename)
 		free(filename);
+
 error_closedir:
-	closedir(dp);
+	if (closedir(dp) == -1)
+		perror("iioutils_get_type(): Failed to close directory");
+
 error_free_builtname_generic:
 	free(builtname_generic);
 error_free_builtname:
 	free(builtname);
 error_free_scan_el_dir:
 	free(scan_el_dir);
-error_ret:
+
 	return ret;
 }
 
-int iioutils_get_param_float(float *output,
-				    const char *param_name,
-				    const char *device_dir,
-				    const char *name,
-				    const char *generic_name)
+/**
+ * iioutils_get_param_float() - read a float value from a channel parameter
+ * @output: output the float value
+ * @param_name: the parameter name to read
+ * @device_dir: the IIO device directory in sysfs
+ * @name: the channel name
+ * @generic_name: the channel type name
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
+ **/
+int iioutils_get_param_float(float *output, const char *param_name,
+			     const char *device_dir, const char *name,
+			     const char *generic_name)
 {
 	FILE *sysfsfp;
 	int ret;
@@ -193,22 +225,24 @@ int iioutils_get_param_float(float *output,
 	const struct dirent *ent;
 
 	ret = asprintf(&builtname, "%s_%s", name, param_name);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
+	if (ret < 0)
+		return -ENOMEM;
+
 	ret = asprintf(&builtname_generic,
 		       "%s_%s", generic_name, param_name);
 	if (ret < 0) {
 		ret = -ENOMEM;
 		goto error_free_builtname;
 	}
+
 	dp = opendir(device_dir);
-	if (dp == NULL) {
+	if (!dp) {
 		ret = -errno;
 		goto error_free_builtname_generic;
 	}
-	while (ent = readdir(dp), ent != NULL)
+
+	ret = -ENOENT;
+	while (ent = readdir(dp), ent)
 		if ((strcmp(builtname, ent->d_name) == 0) ||
 		    (strcmp(builtname_generic, ent->d_name) == 0)) {
 			ret = asprintf(&filename,
@@ -217,60 +251,69 @@ int iioutils_get_param_float(float *output,
 				ret = -ENOMEM;
 				goto error_closedir;
 			}
+
 			sysfsfp = fopen(filename, "r");
 			if (!sysfsfp) {
 				ret = -errno;
 				goto error_free_filename;
 			}
-			fscanf(sysfsfp, "%f", output);
+
+			errno = 0;
+			if (fscanf(sysfsfp, "%f", output) != 1)
+				ret = errno ? -errno : -ENODATA;
+
 			break;
 		}
 error_free_filename:
 	if (filename)
 		free(filename);
+
 error_closedir:
-	closedir(dp);
+	if (closedir(dp) == -1)
+		perror("iioutils_get_param_float(): Failed to close directory");
+
 error_free_builtname_generic:
 	free(builtname_generic);
 error_free_builtname:
 	free(builtname);
-error_ret:
+
 	return ret;
 }
 
 /**
- * bsort_channel_array_by_index() - reorder so that the array is in index order
- *
+ * bsort_channel_array_by_index() - sort the array in index order
+ * @ci_array: the iio_channel_info array to be sorted
+ * @cnt: the amount of array elements
  **/
 
-void bsort_channel_array_by_index(struct iio_channel_info **ci_array,
-					 int cnt)
+void bsort_channel_array_by_index(struct iio_channel_info *ci_array, int cnt)
 {
-
 	struct iio_channel_info temp;
 	int x, y;
 
 	for (x = 0; x < cnt; x++)
 		for (y = 0; y < (cnt - 1); y++)
-			if ((*ci_array)[y].index > (*ci_array)[y+1].index) {
-				temp = (*ci_array)[y + 1];
-				(*ci_array)[y + 1] = (*ci_array)[y];
-				(*ci_array)[y] = temp;
+			if (ci_array[y].index > ci_array[y + 1].index) {
+				temp = ci_array[y + 1];
+				ci_array[y + 1] = ci_array[y];
+				ci_array[y] = temp;
 			}
 }
 
 /**
  * build_channel_array() - function to figure out what channels are present
  * @device_dir: the IIO device directory in sysfs
- * @
+ * @ci_array: output the resulting array of iio_channel_info
+ * @counter: output the amount of array elements
+ *
+ * Returns 0 on success, otherwise a negative error code.
  **/
 int build_channel_array(const char *device_dir,
-			      struct iio_channel_info **ci_array,
-			      int *counter)
+			struct iio_channel_info **ci_array, int *counter)
 {
 	DIR *dp;
 	FILE *sysfsfp;
-	int count, i;
+	int count = 0, i;
 	struct iio_channel_info *current;
 	int ret;
 	const struct dirent *ent;
@@ -279,16 +322,16 @@ int build_channel_array(const char *device_dir,
 
 	*counter = 0;
 	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
+	if (ret < 0)
+		return -ENOMEM;
+
 	dp = opendir(scan_el_dir);
-	if (dp == NULL) {
+	if (!dp) {
 		ret = -errno;
 		goto error_free_name;
 	}
-	while (ent = readdir(dp), ent != NULL)
+
+	while (ent = readdir(dp), ent)
 		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
 			   "_en") == 0) {
 			ret = asprintf(&filename,
@@ -297,26 +340,43 @@ int build_channel_array(const char *device_dir,
 				ret = -ENOMEM;
 				goto error_close_dir;
 			}
+
 			sysfsfp = fopen(filename, "r");
-			if (sysfsfp == NULL) {
+			if (!sysfsfp) {
 				ret = -errno;
 				free(filename);
 				goto error_close_dir;
 			}
-			fscanf(sysfsfp, "%i", &ret);
+
+			errno = 0;
+			if (fscanf(sysfsfp, "%i", &ret) != 1) {
+				ret = errno ? -errno : -ENODATA;
+				if (fclose(sysfsfp))
+					perror("build_channel_array(): Failed to close file");
+
+				free(filename);
+				goto error_close_dir;
+			}
 			if (ret == 1)
 				(*counter)++;
-			fclose(sysfsfp);
+
+			if (fclose(sysfsfp)) {
+				ret = -errno;
+				free(filename);
+				goto error_close_dir;
+			}
+
 			free(filename);
 		}
+
 	*ci_array = malloc(sizeof(**ci_array) * (*counter));
-	if (*ci_array == NULL) {
+	if (!*ci_array) {
 		ret = -ENOMEM;
 		goto error_close_dir;
 	}
+
 	seekdir(dp, 0);
-	count = 0;
-	while (ent = readdir(dp), ent != NULL) {
+	while (ent = readdir(dp), ent) {
 		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
 			   "_en") == 0) {
 			int current_enabled = 0;
@@ -330,14 +390,29 @@ int build_channel_array(const char *device_dir,
 				count--;
 				goto error_cleanup_array;
 			}
+
 			sysfsfp = fopen(filename, "r");
-			if (sysfsfp == NULL) {
+			if (!sysfsfp) {
+				ret = -errno;
 				free(filename);
+				count--;
+				goto error_cleanup_array;
+			}
+
+			errno = 0;
+			if (fscanf(sysfsfp, "%i", &current_enabled) != 1) {
+				ret = errno ? -errno : -ENODATA;
+				free(filename);
+				count--;
+				goto error_cleanup_array;
+			}
+
+			if (fclose(sysfsfp)) {
 				ret = -errno;
+				free(filename);
+				count--;
 				goto error_cleanup_array;
 			}
-			fscanf(sysfsfp, "%i", &current_enabled);
-			fclose(sysfsfp);
 
 			if (!current_enabled) {
 				free(filename);
@@ -350,18 +425,23 @@ int build_channel_array(const char *device_dir,
 			current->name = strndup(ent->d_name,
 						strlen(ent->d_name) -
 						strlen("_en"));
-			if (current->name == NULL) {
+			if (!current->name) {
 				free(filename);
 				ret = -ENOMEM;
+				count--;
 				goto error_cleanup_array;
 			}
+
 			/* Get the generic and specific name elements */
 			ret = iioutils_break_up_name(current->name,
 						     &current->generic_name);
 			if (ret) {
 				free(filename);
+				free(current->name);
+				count--;
 				goto error_cleanup_array;
 			}
+
 			ret = asprintf(&filename,
 				       "%s/%s_index",
 				       scan_el_dir,
@@ -371,9 +451,32 @@ int build_channel_array(const char *device_dir,
 				ret = -ENOMEM;
 				goto error_cleanup_array;
 			}
+
 			sysfsfp = fopen(filename, "r");
-			fscanf(sysfsfp, "%u", &current->index);
-			fclose(sysfsfp);
+			if (!sysfsfp) {
+				ret = -errno;
+				fprintf(stderr, "failed to open %s\n",
+					filename);
+				free(filename);
+				goto error_cleanup_array;
+			}
+
+			errno = 0;
+			if (fscanf(sysfsfp, "%u", &current->index) != 1) {
+				ret = errno ? -errno : -ENODATA;
+				if (fclose(sysfsfp))
+					perror("build_channel_array(): Failed to close file");
+
+				free(filename);
+				goto error_cleanup_array;
+			}
+
+			if (fclose(sysfsfp)) {
+				ret = -errno;
+				free(filename);
+				goto error_cleanup_array;
+			}
+
 			free(filename);
 			/* Find the scale */
 			ret = iioutils_get_param_float(&current->scale,
@@ -381,15 +484,17 @@ int build_channel_array(const char *device_dir,
 						       device_dir,
 						       current->name,
 						       current->generic_name);
-			if (ret < 0)
+			if ((ret < 0) && (ret != -ENOENT))
 				goto error_cleanup_array;
+
 			ret = iioutils_get_param_float(&current->offset,
 						       "offset",
 						       device_dir,
 						       current->name,
 						       current->generic_name);
-			if (ret < 0)
+			if ((ret < 0) && (ret != -ENOENT))
 				goto error_cleanup_array;
+
 			ret = iioutils_get_type(&current->is_signed,
 						&current->bytes,
 						&current->bits_used,
@@ -399,182 +504,317 @@ int build_channel_array(const char *device_dir,
 						device_dir,
 						current->name,
 						current->generic_name);
+			if (ret < 0)
+				goto error_cleanup_array;
 		}
 	}
 
-	closedir(dp);
+	if (closedir(dp) == -1) {
+		ret = -errno;
+		goto error_cleanup_array;
+	}
+
+	free(scan_el_dir);
 	/* reorder so that the array is in index order */
-	bsort_channel_array_by_index(ci_array, *counter);
+	bsort_channel_array_by_index(*ci_array, *counter);
 
 	return 0;
 
 error_cleanup_array:
-	for (i = count - 1;  i >= 0; i--)
+	for (i = count - 1;  i >= 0; i--) {
 		free((*ci_array)[i].name);
+		free((*ci_array)[i].generic_name);
+	}
 	free(*ci_array);
+	*ci_array = NULL;
+	*counter = 0;
 error_close_dir:
-	closedir(dp);
+	if (dp)
+		if (closedir(dp) == -1)
+			perror("build_channel_array(): Failed to close dir");
+
 error_free_name:
 	free(scan_el_dir);
-error_ret:
+
 	return ret;
 }
 
+static int calc_digits(int num)
+{
+	int count = 0;
+
+	while (num != 0) {
+		num /= 10;
+		count++;
+	}
+
+	return count;
+}
+
 /**
  * find_type_by_name() - function to match top level types by name
  * @name: top level type instance name
- * @type: the type of top level instance being sort
+ * @type: the type of top level instance being searched
  *
+ * Returns the device number of a matched IIO device on success, otherwise a
+ * negative error code.
  * Typical types this is used for are device and trigger.
  **/
 int find_type_by_name(const char *name, const char *type)
 {
 	const struct dirent *ent;
-	int number, numstrlen;
+	int number, numstrlen, ret;
 
-	FILE *nameFile;
+	FILE *namefp;
 	DIR *dp;
 	char thisname[IIO_MAX_NAME_LENGTH];
 	char *filename;
 
 	dp = opendir(iio_dir);
-	if (dp == NULL) {
-		printf("No industrialio devices available\n");
+	if (!dp) {
+		fprintf(stderr, "No industrialio devices available\n");
 		return -ENODEV;
 	}
 
-	while (ent = readdir(dp), ent != NULL) {
+	while (ent = readdir(dp), ent) {
 		if (strcmp(ent->d_name, ".") != 0 &&
-			strcmp(ent->d_name, "..") != 0 &&
-			strlen(ent->d_name) > strlen(type) &&
-			strncmp(ent->d_name, type, strlen(type)) == 0) {
-			numstrlen = sscanf(ent->d_name + strlen(type),
-					   "%d",
-					   &number);
+		    strcmp(ent->d_name, "..") != 0 &&
+		    strlen(ent->d_name) > strlen(type) &&
+		    strncmp(ent->d_name, type, strlen(type)) == 0) {
+			errno = 0;
+			ret = sscanf(ent->d_name + strlen(type), "%d", &number);
+			if (ret < 0) {
+				ret = -errno;
+				fprintf(stderr,
+					"failed to read element number\n");
+				goto error_close_dir;
+			} else if (ret != 1) {
+				ret = -EIO;
+				fprintf(stderr,
+					"failed to match element number\n");
+				goto error_close_dir;
+			}
+
+			numstrlen = calc_digits(number);
 			/* verify the next character is not a colon */
 			if (strncmp(ent->d_name + strlen(type) + numstrlen,
-					":",
-					1) != 0) {
-				filename = malloc(strlen(iio_dir)
-						+ strlen(type)
-						+ numstrlen
-						+ 6);
-				if (filename == NULL) {
-					closedir(dp);
-					return -ENOMEM;
+			    ":", 1) != 0) {
+				filename = malloc(strlen(iio_dir) + strlen(type)
+						  + numstrlen + 6);
+				if (!filename) {
+					ret = -ENOMEM;
+					goto error_close_dir;
 				}
-				sprintf(filename, "%s%s%d/name",
-					iio_dir,
-					type,
-					number);
-				nameFile = fopen(filename, "r");
-				if (!nameFile) {
+
+				ret = sprintf(filename, "%s%s%d/name", iio_dir,
+					      type, number);
+				if (ret < 0) {
+					free(filename);
+					goto error_close_dir;
+				}
+
+				namefp = fopen(filename, "r");
+				if (!namefp) {
 					free(filename);
 					continue;
 				}
+
 				free(filename);
-				fscanf(nameFile, "%s", thisname);
-				fclose(nameFile);
+				errno = 0;
+				if (fscanf(namefp, "%s", thisname) != 1) {
+					ret = errno ? -errno : -ENODATA;
+					goto error_close_dir;
+				}
+
+				if (fclose(namefp)) {
+					ret = -errno;
+					goto error_close_dir;
+				}
+
 				if (strcmp(name, thisname) == 0) {
-					closedir(dp);
+					if (closedir(dp) == -1)
+						return -errno;
+
 					return number;
 				}
 			}
 		}
 	}
-	closedir(dp);
+	if (closedir(dp) == -1)
+		return -errno;
+
 	return -ENODEV;
+
+error_close_dir:
+	if (closedir(dp) == -1)
+		perror("find_type_by_name(): Failed to close directory");
+
+	return ret;
 }
 
-int _write_sysfs_int(char *filename, char *basedir, int val, int verify)
+static int _write_sysfs_int(const char *filename, const char *basedir, int val,
+			    int verify)
 {
 	int ret = 0;
 	FILE *sysfsfp;
 	int test;
 	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
 
-	if (temp == NULL)
+	if (!temp)
 		return -ENOMEM;
-	sprintf(temp, "%s/%s", basedir, filename);
+
+	ret = sprintf(temp, "%s/%s", basedir, filename);
+	if (ret < 0)
+		goto error_free;
+
 	sysfsfp = fopen(temp, "w");
-	if (sysfsfp == NULL) {
-		printf("failed to open %s\n", temp);
+	if (!sysfsfp) {
 		ret = -errno;
+		fprintf(stderr, "failed to open %s\n", temp);
+		goto error_free;
+	}
+
+	ret = fprintf(sysfsfp, "%d", val);
+	if (ret < 0) {
+		if (fclose(sysfsfp))
+			perror("_write_sysfs_int(): Failed to close dir");
+
 		goto error_free;
 	}
-	fprintf(sysfsfp, "%d", val);
-	fclose(sysfsfp);
+
+	if (fclose(sysfsfp)) {
+		ret = -errno;
+		goto error_free;
+	}
+
 	if (verify) {
 		sysfsfp = fopen(temp, "r");
-		if (sysfsfp == NULL) {
-			printf("failed to open %s\n", temp);
+		if (!sysfsfp) {
+			ret = -errno;
+			fprintf(stderr, "failed to open %s\n", temp);
+			goto error_free;
+		}
+
+		if (fscanf(sysfsfp, "%d", &test) != 1) {
+			ret = errno ? -errno : -ENODATA;
+			if (fclose(sysfsfp))
+				perror("_write_sysfs_int(): Failed to close dir");
+
+			goto error_free;
+		}
+
+		if (fclose(sysfsfp)) {
 			ret = -errno;
 			goto error_free;
 		}
-		fscanf(sysfsfp, "%d", &test);
-		fclose(sysfsfp);
+
 		if (test != val) {
-			printf("Possible failure in int write %d to %s%s\n",
-				val,
-				basedir,
-				filename);
+			fprintf(stderr,
+				"Possible failure in int write %d to %s/%s\n",
+				val, basedir, filename);
 			ret = -1;
 		}
 	}
+
 error_free:
 	free(temp);
 	return ret;
 }
 
-int write_sysfs_int(char *filename, char *basedir, int val)
+/**
+ * write_sysfs_int() - write an integer value to a sysfs file
+ * @filename: name of the file to write to
+ * @basedir: the sysfs directory in which the file is to be found
+ * @val: integer value to write to file
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
+ **/
+int write_sysfs_int(const char *filename, const char *basedir, int val)
 {
 	return _write_sysfs_int(filename, basedir, val, 0);
 }
 
-int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
+/**
+ * write_sysfs_int_and_verify() - write an integer value to a sysfs file
+ *				  and verify
+ * @filename: name of the file to write to
+ * @basedir: the sysfs directory in which the file is to be found
+ * @val: integer value to write to file
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
+ **/
+int write_sysfs_int_and_verify(const char *filename, const char *basedir,
+			       int val)
 {
 	return _write_sysfs_int(filename, basedir, val, 1);
 }
 
-int _write_sysfs_string(char *filename, char *basedir, char *val, int verify)
+static int _write_sysfs_string(const char *filename, const char *basedir,
+			       const char *val, int verify)
 {
 	int ret = 0;
 	FILE  *sysfsfp;
 	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
 
-	if (temp == NULL) {
-		printf("Memory allocation failed\n");
+	if (!temp) {
+		fprintf(stderr, "Memory allocation failed\n");
 		return -ENOMEM;
 	}
-	sprintf(temp, "%s/%s", basedir, filename);
+
+	ret = sprintf(temp, "%s/%s", basedir, filename);
+	if (ret < 0)
+		goto error_free;
+
 	sysfsfp = fopen(temp, "w");
-	if (sysfsfp == NULL) {
-		printf("Could not open %s\n", temp);
+	if (!sysfsfp) {
+		ret = -errno;
+		fprintf(stderr, "Could not open %s\n", temp);
+		goto error_free;
+	}
+
+	ret = fprintf(sysfsfp, "%s", val);
+	if (ret < 0) {
+		if (fclose(sysfsfp))
+			perror("_write_sysfs_string(): Failed to close dir");
+
+		goto error_free;
+	}
+
+	if (fclose(sysfsfp)) {
 		ret = -errno;
 		goto error_free;
 	}
-	fprintf(sysfsfp, "%s", val);
-	fclose(sysfsfp);
+
 	if (verify) {
 		sysfsfp = fopen(temp, "r");
-		if (sysfsfp == NULL) {
-			printf("could not open file to verify\n");
+		if (!sysfsfp) {
 			ret = -errno;
+			fprintf(stderr, "Could not open file to verify\n");
 			goto error_free;
 		}
-		fscanf(sysfsfp, "%s", temp);
-		fclose(sysfsfp);
+
+		if (fscanf(sysfsfp, "%s", temp) != 1) {
+			ret = errno ? -errno : -ENODATA;
+			if (fclose(sysfsfp))
+				perror("_write_sysfs_string(): Failed to close dir");
+
+			goto error_free;
+		}
+
+		if (fclose(sysfsfp)) {
+			ret = -errno;
+			goto error_free;
+		}
+
 		if (strcmp(temp, val) != 0) {
-			printf("Possible failure in string write of %s "
-				"Should be %s "
-				"written to %s\%s\n",
-				temp,
-				val,
-				basedir,
-				filename);
+			fprintf(stderr,
+				"Possible failure in string write of %s "
+				"Should be %s written to %s/%s\n", temp, val,
+				basedir, filename);
 			ret = -1;
 		}
 	}
+
 error_free:
 	free(temp);
 
@@ -586,84 +826,166 @@ error_free:
  * @filename: name of file to write to
  * @basedir: the sysfs directory in which the file is to be found
  * @val: the string to write
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
  **/
-int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
+int write_sysfs_string_and_verify(const char *filename, const char *basedir,
+				  const char *val)
 {
 	return _write_sysfs_string(filename, basedir, val, 1);
 }
 
-int write_sysfs_string(char *filename, char *basedir, char *val)
+/**
+ * write_sysfs_string() - write string to a sysfs file
+ * @filename: name of file to write to
+ * @basedir: the sysfs directory in which the file is to be found
+ * @val: the string to write
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
+ **/
+int write_sysfs_string(const char *filename, const char *basedir,
+		       const char *val)
 {
 	return _write_sysfs_string(filename, basedir, val, 0);
 }
 
-int read_sysfs_posint(char *filename, char *basedir)
+/**
+ * read_sysfs_posint() - read an integer value from file
+ * @filename: name of file to read from
+ * @basedir: the sysfs directory in which the file is to be found
+ *
+ * Returns the read integer value >= 0 on success, otherwise a negative error
+ * code.
+ **/
+int read_sysfs_posint(const char *filename, const char *basedir)
 {
 	int ret;
 	FILE  *sysfsfp;
 	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
 
-	if (temp == NULL) {
-		printf("Memory allocation failed");
+	if (!temp) {
+		fprintf(stderr, "Memory allocation failed");
 		return -ENOMEM;
 	}
-	sprintf(temp, "%s/%s", basedir, filename);
+
+	ret = sprintf(temp, "%s/%s", basedir, filename);
+	if (ret < 0)
+		goto error_free;
+
 	sysfsfp = fopen(temp, "r");
-	if (sysfsfp == NULL) {
+	if (!sysfsfp) {
 		ret = -errno;
 		goto error_free;
 	}
-	fscanf(sysfsfp, "%d\n", &ret);
-	fclose(sysfsfp);
+
+	errno = 0;
+	if (fscanf(sysfsfp, "%d\n", &ret) != 1) {
+		ret = errno ? -errno : -ENODATA;
+		if (fclose(sysfsfp))
+			perror("read_sysfs_posint(): Failed to close dir");
+
+		goto error_free;
+	}
+
+	if (fclose(sysfsfp))
+		ret = -errno;
+
 error_free:
 	free(temp);
+
 	return ret;
 }
 
-int read_sysfs_float(char *filename, char *basedir, float *val)
+/**
+ * read_sysfs_float() - read a float value from file
+ * @filename: name of file to read from
+ * @basedir: the sysfs directory in which the file is to be found
+ * @val: output the read float value
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
+ **/
+int read_sysfs_float(const char *filename, const char *basedir, float *val)
 {
 	int ret = 0;
 	FILE  *sysfsfp;
 	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
 
-	if (temp == NULL) {
-		printf("Memory allocation failed");
+	if (!temp) {
+		fprintf(stderr, "Memory allocation failed");
 		return -ENOMEM;
 	}
-	sprintf(temp, "%s/%s", basedir, filename);
+
+	ret = sprintf(temp, "%s/%s", basedir, filename);
+	if (ret < 0)
+		goto error_free;
+
 	sysfsfp = fopen(temp, "r");
-	if (sysfsfp == NULL) {
+	if (!sysfsfp) {
 		ret = -errno;
 		goto error_free;
 	}
-	fscanf(sysfsfp, "%f\n", val);
-	fclose(sysfsfp);
+
+	errno = 0;
+	if (fscanf(sysfsfp, "%f\n", val) != 1) {
+		ret = errno ? -errno : -ENODATA;
+		if (fclose(sysfsfp))
+			perror("read_sysfs_float(): Failed to close dir");
+
+		goto error_free;
+	}
+
+	if (fclose(sysfsfp))
+		ret = -errno;
+
 error_free:
 	free(temp);
+
 	return ret;
 }
 
+/**
+ * read_sysfs_string() - read a string from file
+ * @filename: name of file to read from
+ * @basedir: the sysfs directory in which the file is to be found
+ * @str: output the read string
+ *
+ * Returns a value >= 0 on success, otherwise a negative error code.
+ **/
 int read_sysfs_string(const char *filename, const char *basedir, char *str)
 {
 	int ret = 0;
 	FILE  *sysfsfp;
 	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
 
-	if (temp == NULL) {
-		printf("Memory allocation failed");
+	if (!temp) {
+		fprintf(stderr, "Memory allocation failed");
 		return -ENOMEM;
 	}
-	sprintf(temp, "%s/%s", basedir, filename);
+
+	ret = sprintf(temp, "%s/%s", basedir, filename);
+	if (ret < 0)
+		goto error_free;
+
 	sysfsfp = fopen(temp, "r");
-	if (sysfsfp == NULL) {
+	if (!sysfsfp) {
 		ret = -errno;
 		goto error_free;
 	}
-	fscanf(sysfsfp, "%s\n", str);
-	fclose(sysfsfp);
+
+	errno = 0;
+	if (fscanf(sysfsfp, "%s\n", str) != 1) {
+		ret = errno ? -errno : -ENODATA;
+		if (fclose(sysfsfp))
+			perror("read_sysfs_string(): Failed to close dir");
+
+		goto error_free;
+	}
+
+	if (fclose(sysfsfp))
+		ret = -errno;
+
 error_free:
 	free(temp);
+
 	return ret;
 }
-
-#endif /* _IIO_UTILS_H */
diff --git a/kernel/tools/iio/iio_utils.h b/kernel/tools/iio/iio_utils.h
index 1bc837b2d..e3503bfe5 100644
--- a/kernel/tools/iio/iio_utils.h
+++ b/kernel/tools/iio/iio_utils.h
@@ -18,6 +18,8 @@
 #define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
 #define FORMAT_TYPE_FILE "%s_type"
 
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
+
 extern const char *iio_dir;
 
 /**
@@ -28,9 +30,12 @@ extern const char *iio_dir;
  * @offset: offset to be applied for conversion to si units
  * @index: the channel index in the buffer output
  * @bytes: number of bytes occupied in buffer output
+ * @bits_used: number of valid bits of data
+ * @shift: amount of bits to shift right data before applying bit mask
  * @mask: a bit mask for the raw output
+ * @be: flag if data is big endian
  * @is_signed: is the raw value stored signed
- * @enabled: is this channel enabled
+ * @location: data offset for this channel inside the buffer (in bytes)
  **/
 struct iio_channel_info {
 	char *name;
@@ -48,24 +53,26 @@ struct iio_channel_info {
 };
 
 int iioutils_break_up_name(const char *full_name, char **generic_name);
-int iioutils_get_type(unsigned *is_signed, unsigned *bytes,
-					  unsigned *bits_used, unsigned *shift,
-					  uint64_t *mask, unsigned *be,
-					  const char *device_dir, const char *name,
-					  const char *generic_name);
+int iioutils_get_type(unsigned *is_signed, unsigned *bytes, unsigned *bits_used,
+		      unsigned *shift, uint64_t *mask, unsigned *be,
+		      const char *device_dir, const char *name,
+		      const char *generic_name);
 int iioutils_get_param_float(float *output, const char *param_name,
-							 const char *device_dir, const char *name,
-							 const char *generic_name);
-void bsort_channel_array_by_index(struct iio_channel_info **ci_array, int cnt);
+			     const char *device_dir, const char *name,
+			     const char *generic_name);
+void bsort_channel_array_by_index(struct iio_channel_info *ci_array, int cnt);
 int build_channel_array(const char *device_dir,
-						struct iio_channel_info **ci_array, int *counter);
+			struct iio_channel_info **ci_array, int *counter);
 int find_type_by_name(const char *name, const char *type);
-int write_sysfs_int(char *filename, char *basedir, int val);
-int write_sysfs_int_and_verify(char *filename, char *basedir, int val);
-int write_sysfs_string_and_verify(char *filename, char *basedir, char *val);
-int write_sysfs_string(char *filename, char *basedir, char *val);
-int read_sysfs_posint(char *filename, char *basedir);
-int read_sysfs_float(char *filename, char *basedir, float *val);
+int write_sysfs_int(const char *filename, const char *basedir, int val);
+int write_sysfs_int_and_verify(const char *filename, const char *basedir,
+			       int val);
+int write_sysfs_string_and_verify(const char *filename, const char *basedir,
+				  const char *val);
+int write_sysfs_string(const char *filename, const char *basedir,
+		       const char *val);
+int read_sysfs_posint(const char *filename, const char *basedir);
+int read_sysfs_float(const char *filename, const char *basedir, float *val);
 int read_sysfs_string(const char *filename, const char *basedir, char *str);
 
 #endif /* _IIO_UTILS_H_ */
diff --git a/kernel/tools/iio/lsiio.c b/kernel/tools/iio/lsiio.c
index c585440f8..3d650e668 100644
--- a/kernel/tools/iio/lsiio.c
+++ b/kernel/tools/iio/lsiio.c
@@ -20,7 +20,6 @@
 #include <sys/dir.h>
 #include "iio_utils.h"
 
-
 static enum verbosity {
 	VERBLEVEL_DEFAULT,	/* 0 gives lspci behaviour */
 	VERBLEVEL_SENSORS,	/* 1 lists sensors */
@@ -29,17 +28,16 @@ static enum verbosity {
 const char *type_device = "iio:device";
 const char *type_trigger = "trigger";
 
-
 static inline int check_prefix(const char *str, const char *prefix)
 {
 	return strlen(str) > strlen(prefix) &&
-		strncmp(str, prefix, strlen(prefix)) == 0;
+	       strncmp(str, prefix, strlen(prefix)) == 0;
 }
 
 static inline int check_postfix(const char *str, const char *postfix)
 {
 	return strlen(str) > strlen(postfix) &&
-		strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
+	       strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
 }
 
 static int dump_channels(const char *dev_dir_name)
@@ -48,32 +46,37 @@ static int dump_channels(const char *dev_dir_name)
 	const struct dirent *ent;
 
 	dp = opendir(dev_dir_name);
-	if (dp == NULL)
+	if (!dp)
 		return -errno;
-	while (ent = readdir(dp), ent != NULL)
+
+	while (ent = readdir(dp), ent)
 		if (check_prefix(ent->d_name, "in_") &&
-		    check_postfix(ent->d_name, "_raw")) {
+		    check_postfix(ent->d_name, "_raw"))
 			printf("   %-10s\n", ent->d_name);
-		}
 
-	return 0;
+	return (closedir(dp) == -1) ? -errno : 0;
 }
 
 static int dump_one_device(const char *dev_dir_name)
 {
 	char name[IIO_MAX_NAME_LENGTH];
 	int dev_idx;
-	int retval;
+	int ret;
 
-	retval = sscanf(dev_dir_name + strlen(iio_dir) + strlen(type_device),
-			"%i", &dev_idx);
-	if (retval != 1)
+	ret = sscanf(dev_dir_name + strlen(iio_dir) + strlen(type_device), "%i",
+		     &dev_idx);
+	if (ret != 1)
 		return -EINVAL;
-	read_sysfs_string("name", dev_dir_name, name);
+
+	ret = read_sysfs_string("name", dev_dir_name, name);
+	if (ret < 0)
+		return ret;
+
 	printf("Device %03d: %s\n", dev_idx, name);
 
 	if (verblevel >= VERBLEVEL_SENSORS)
 		return dump_channels(dev_dir_name);
+
 	return 0;
 }
 
@@ -81,57 +84,90 @@ static int dump_one_trigger(const char *dev_dir_name)
 {
 	char name[IIO_MAX_NAME_LENGTH];
 	int dev_idx;
-	int retval;
+	int ret;
 
-	retval = sscanf(dev_dir_name + strlen(iio_dir) + strlen(type_trigger),
-			"%i", &dev_idx);
-	if (retval != 1)
+	ret = sscanf(dev_dir_name + strlen(iio_dir) + strlen(type_trigger),
+		     "%i", &dev_idx);
+	if (ret != 1)
 		return -EINVAL;
-	read_sysfs_string("name", dev_dir_name, name);
+
+	ret = read_sysfs_string("name", dev_dir_name, name);
+	if (ret < 0)
+		return ret;
+
 	printf("Trigger %03d: %s\n", dev_idx, name);
+
 	return 0;
 }
 
-static void dump_devices(void)
+static int dump_devices(void)
 {
 	const struct dirent *ent;
+	int ret;
 	DIR *dp;
 
 	dp = opendir(iio_dir);
-	if (dp == NULL) {
-		printf("No industrial I/O devices available\n");
-		return;
+	if (!dp) {
+		fprintf(stderr, "No industrial I/O devices available\n");
+		return -ENODEV;
 	}
 
-	while (ent = readdir(dp), ent != NULL) {
+	while (ent = readdir(dp), ent) {
 		if (check_prefix(ent->d_name, type_device)) {
 			char *dev_dir_name;
 
-			asprintf(&dev_dir_name, "%s%s", iio_dir, ent->d_name);
-			dump_one_device(dev_dir_name);
+			if (asprintf(&dev_dir_name, "%s%s", iio_dir,
+				     ent->d_name) < 0) {
+				ret = -ENOMEM;
+				goto error_close_dir;
+			}
+
+			ret = dump_one_device(dev_dir_name);
+			if (ret) {
+				free(dev_dir_name);
+				goto error_close_dir;
+			}
+
 			free(dev_dir_name);
 			if (verblevel >= VERBLEVEL_SENSORS)
 				printf("\n");
 		}
 	}
 	rewinddir(dp);
-	while (ent = readdir(dp), ent != NULL) {
+	while (ent = readdir(dp), ent) {
 		if (check_prefix(ent->d_name, type_trigger)) {
 			char *dev_dir_name;
 
-			asprintf(&dev_dir_name, "%s%s", iio_dir, ent->d_name);
-			dump_one_trigger(dev_dir_name);
+			if (asprintf(&dev_dir_name, "%s%s", iio_dir,
+				     ent->d_name) < 0) {
+				ret = -ENOMEM;
+				goto error_close_dir;
+			}
+
+			ret = dump_one_trigger(dev_dir_name);
+			if (ret) {
+				free(dev_dir_name);
+				goto error_close_dir;
+			}
+
 			free(dev_dir_name);
 		}
 	}
-	closedir(dp);
+
+	return (closedir(dp) == -1) ? -errno : 0;
+
+error_close_dir:
+	if (closedir(dp) == -1)
+		perror("dump_devices(): Failed to close directory");
+
+	return ret;
 }
 
 int main(int argc, char **argv)
 {
 	int c, err = 0;
 
-	while ((c = getopt(argc, argv, "d:D:v")) != EOF) {
+	while ((c = getopt(argc, argv, "v")) != EOF) {
 		switch (c) {
 		case 'v':
 			verblevel++;
@@ -146,13 +182,9 @@ int main(int argc, char **argv)
 	if (err || argc > optind) {
 		fprintf(stderr, "Usage: lsiio [options]...\n"
 			"List industrial I/O devices\n"
-			"  -v, --verbose\n"
-			"      Increase verbosity (may be given multiple times)\n"
-			);
+			"  -v  Increase verbosity (may be given multiple times)\n");
 		exit(1);
 	}
 
-	dump_devices();
-
-	return 0;
+	return dump_devices();
 }