Merge tag 'iio-for-5.13a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

1st set of IIO/counter device support, features and cleanup in the 5.13 cycle

Big set in here from Alexandru Ardelean enabling multiple buffer support.
This includes providing a new directory per buffer that combines
what was previously in buffer/ and scan_elements/. Old interfaces still
in place for compatiblity.

Note immuatable branch for scmi patches to allow for some significant
rework going on in that subsystem.  Merge required updating to reflect
some changes in IIO.

Late rebase to fix some wrong fixes tags due to some earlier rebases
made necessary by messing up the immutable branch.

IIO New Device Support
* adi,ad5686
  - Add info to support AD5673R and AD5677R
* bosch,bmi088
  - New driver supporting this accelerometer + gyroscope
* cros_ec_mkbp
  - New driver for this proximity sensor that exposes a 'front'
    sensor. Very simple switch like device, but driver allows it
    to share interface with more sophisticated proximity sensors.
* iio_scmi
  - New driver to support ARM SCMI protocol to expose underlying
    accelerometers and gyroscopes via this firmware interface.
* st,st_magn
  - Add ID for IISMDC magnetometer.
* ti,ads131e0
  - New driver supporting ads131e04, ads131e06 and ads131e08 24 bit ADCs

Counter New Device Support
* IRQ or GPIO based counter
  - New driver for a conceptually simple counter that uses interrupts
    to perform the count.

Features
* core
  - Dual buffer supprt including:
     Various helpers to centralize handling of bufferer related elements.
     Document existing and new IOCTLs
     Register the IIO chrdev only if it can actually be used for anything.
     Rework attribute group creation in the core (lots of patches)
     Merge buffer/ and scan_elements/ entries into one list + maintain
     backwards compatible set.
     Introduce the internal logic and IOCTL to allow multiple buffers
     + access to an anon FD per buffer to actually read from it.
     Tidy up tools/iio/iio_generic_buffer and switch to new interfaces.
     Update ABI docs.
     A few follow up fixes, unsuprising as this was a huge bit of rework.
  - Move common case setting of trig->parent to the core.
  - Provide an iio_read_channel_processed_scale() to avoid loss of
    precision from iio_read_channel_processed() then applying integer
    scale. Use it in ntc_thermistor driver in hwmon.
  - Allow drivers to specify labels from elsewhere than DT. Use it for
    bmc150 and kxcjk-1013 labels related to position on 2 in one tablets.
  - Document label usage for proximity and accelerometer sensors.
  - Some local variable renames for consistency
tools
  - Add -a parameter to iio_event_monitor to allow autoenabling of events.
* acpi_als
  - Add trigger support for devices that don't support notification method.
* adi,ad7124
  - Allow more than 8 channels.  This is a complex little device, but is
    capable of supporting up to 16 channels if the share certain
    configuration settings.
* hrtimer-trigger
  - Support sampling frequency below 1Hz.
* mediatek,mt8195-auxadc
  - Add compatible to binding docs (always also includes mt8173)
* st,stm32-adc
  - Enable timetamps when not using DMA.
* vishay,vcnl3020
  - Sampling frequency control.

Cleanup and minor fixes:
* treewide
  - Use some getter and setter functions instead of opencoding.
  - Set of fixes for pointless casts in various drivers.
  - Avoid wrong kernel-doc marking on comment blocks.
  - Fix various other minor kernel-doc issues shown by W=1
* core
  - Use a signed temporary for IIO_VAL_FRACTIONAL_LOG2 to avoid odd casts.
  - Fix IIO_VAL_FRACTIONAL_LOG2 for values between -1.0 and 0.0
  - Add unit tests for iio_format_value()
* docs
  - Fix formatting/typos in iio_configfs.rst and buffers.rst
  - Add documentation of index in buffers.rst
  - Fix scan element description
  - Avoid some issues with HTML generation from ABI docs by moving
    duplicated defintions to more generic files.
  - Drop reference to long dead mailing list.
* 104-quad
  - Remove left over deprecated IIO counter ABI.
* adi,adi-axi-adc
  - Fix wrong bit of docs.
* adi,ad5791
  - Typos
* adi,ad9834
   - Switch to device managed functions in probe.
* adi,adis*
  - Add and use helpers for locking to reduced duplication.
* adi,adis16480
  - Fix calculation of sampling frequency when using pulse per second input.
* adi,adis16475
  - Calculate the IMU scaled internal sampling rate and runtime depending
    on sysfs based configuration rather than getting from DT. Drop now
    unnecessary property from DT bindings doc.
* cros_ec
   - Fix result of a series of recent changes that means extended buffer
     attributes turn up in the wrong place. Too complex to revert the
     various patches unfortunately so this is a bit messy.
* fsl,mma3452
  - Indentation cleanup.
* hid-sensors
  - Size of storage needs to increase for some parts when using quaternions.
  - Move the get sensistivity attribute to hid-sensors-common to reduce
    duplication.  Enable it for more device types.
  - Correctly handle relative sensitivity if reported that way including
    documenting the new ABI.
* maxim,max517
  - Use device managed functions in probe.
* mediatek,mt6360-adc
  - Use asm/unaligned.h instead of directly including
    unaligned/be_byteshift.h
* novuton,npcm-adc
  - Local lock instead of missusing mlock.
* semtech,sx9500
  - Typos
* st,sensor
  - typo fix
* st,spear-adc
  - Local lock instead of missusing mlock.
* st,stm32-adc
  - Long standing HAS_IOMEM dependency fix.
* st,stm32-counter
  - Remove left over deprecated IIO counter ABI.
* ti,palmas-adc
  - Local lock instead of missusing mlock.
* ti,tmp007
  - Switch to device managed functions in probe.

Other
* MAINTAINERS
  - Move Peter Meerwald-Stadler to Credits at his request

* tag 'iio-for-5.13a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (119 commits)
  iio: acpi_als: Add trigger support
  iio: acpi_als: Add local variable dev in probe
  iio: acpi_als: Add timestamp channel
  iio: adc: ad7292: Modify the bool initialization assignment
  iio: cros: unify hw fifo attributes without API changes
  iio: kfifo: add devm_iio_triggered_buffer_setup_ext variant
  iio: event_monitor: Enable events before monitoring
  dt-bindings: iio: adc: Add compatible for Mediatek MT8195
  iio:magnetometer: Add Support for ST IIS2MDC
  dt-bindings: iio: st,st-sensors add IIS2MDC.
  staging: iio: ad9832: kernel-doc fixes
  iio:dac:max517.c: Use devm_iio_device_register()
  iio:cros_ec_sensors: Fix a wrong function name in kernel doc.
  iio: buffer: kfifo_buf: kernel-doc, typo in function name.
  iio: accel: sca3000: kernel-doc fixes. Missing - and wrong function names.
  iio: adc: adi-axi-adc: Drop false marking for kernel-doc
  iio: adc: cpcap-adc: kernel-doc fix - that should be _ in structure name
  iio: dac: ad5504: fix wrong part number in kernel-doc structure name.
  iio: dac: ad5770r: kernel-doc fix case of letter R wrong in structure name
  iio: adc: ti-adc084s021: kernel-doc fixes, missing function names
  ...

5 files changed, 190 insertions, 60 deletions

diff --git a/tools/iio/Makefile b/tools/iio/Makefile
index 3de763d9ab70..5d12ac4e7f8f 100644
--- a/tools/iio/Makefile
+++ b/tools/iio/Makefile
@@ -27,6 +27,7 @@ include $(srctree)/tools/build/Makefile.include
 #
 $(OUTPUT)include/linux/iio: ../../include/uapi/linux/iio
 	mkdir -p $(OUTPUT)include/linux/iio 2>&1 || true
+	ln -sf $(CURDIR)/../../include/uapi/linux/iio/buffer.h $@
 	ln -sf $(CURDIR)/../../include/uapi/linux/iio/events.h $@
 	ln -sf $(CURDIR)/../../include/uapi/linux/iio/types.h $@
 
diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c
index bb03859db89d..0076437f6e3f 100644
--- a/tools/iio/iio_event_monitor.c
+++ b/tools/iio/iio_event_monitor.c
@@ -14,6 +14,7 @@
 
 #include <unistd.h>
 #include <stdlib.h>
+#include <dirent.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <errno.h>
@@ -280,22 +281,69 @@ static void print_event(struct iio_event_data *event)
 	printf("\n");
 }
 
+/* Enable or disable events in sysfs if the knob is available */
+static void enable_events(char *dev_dir, int enable)
+{
+	const struct dirent *ent;
+	char evdir[256];
+	int ret;
+	DIR *dp;
+
+	snprintf(evdir, sizeof(evdir), FORMAT_EVENTS_DIR, dev_dir);
+	evdir[sizeof(evdir)-1] = '\0';
+
+	dp = opendir(evdir);
+	if (!dp) {
+		fprintf(stderr, "Enabling/disabling events: can't open %s\n",
+			evdir);
+		return;
+	}
+
+	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, evdir,
+					      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;
+	}
+}
+
 int main(int argc, char **argv)
 {
 	struct iio_event_data event;
 	const char *device_name;
+	char *dev_dir_name = NULL;
 	char *chrdev_name;
 	int ret;
 	int dev_num;
 	int fd, event_fd;
-
-	if (argc <= 1) {
-		fprintf(stderr, "Usage: %s <device_name>\n", argv[0]);
+	bool all_events = false;
+
+	if (argc == 2) {
+		device_name = argv[1];
+	} else if (argc == 3) {
+		device_name = argv[2];
+		if (!strcmp(argv[1], "-a"))
+			all_events = true;
+	} else {
+		fprintf(stderr,
+			"Usage: iio_event_monitor [options] <device_name>\n"
+			"Listen and display events from IIO devices\n"
+			"  -a         Auto-activate all available events\n");
 		return -1;
 	}
 
-	device_name = argv[1];
-
 	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",
@@ -303,6 +351,10 @@ int main(int argc, char **argv)
 		ret = asprintf(&chrdev_name, "/dev/iio:device%d", dev_num);
 		if (ret < 0)
 			return -ENOMEM;
+		/* Look up sysfs dir as well if we can */
+		ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);
+		if (ret < 0)
+			return -ENOMEM;
 	} else {
 		/*
 		 * If we can't find an IIO device by name assume device_name is
@@ -313,6 +365,9 @@ int main(int argc, char **argv)
 			return -ENOMEM;
 	}
 
+	if (all_events && dev_dir_name)
+		enable_events(dev_dir_name, 1);
+
 	fd = open(chrdev_name, 0);
 	if (fd == -1) {
 		ret = -errno;
@@ -365,6 +420,10 @@ int main(int argc, char **argv)
 		perror("Failed to close event file");
 
 error_free_chrdev_name:
+	/* Disable events after use */
+	if (all_events && dev_dir_name)
+		enable_events(dev_dir_name, 0);
+
 	free(chrdev_name);
 
 	return ret;
diff --git a/tools/iio/iio_generic_buffer.c b/tools/iio/iio_generic_buffer.c
index 34d63bcebcd2..2491c54a5e4f 100644
--- a/tools/iio/iio_generic_buffer.c
+++ b/tools/iio/iio_generic_buffer.c
@@ -30,6 +30,8 @@
 #include <inttypes.h>
 #include <stdbool.h>
 #include <signal.h>
+#include <sys/ioctl.h>
+#include <linux/iio/buffer.h>
 #include "iio_utils.h"
 
 /**
@@ -49,7 +51,7 @@ enum autochan {
  * 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)
+static int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
 {
 	int bytes = 0;
 	int i = 0;
@@ -68,7 +70,7 @@ int size_from_channelarray(struct iio_channel_info *channels, int num_channels)
 	return bytes;
 }
 
-void print1byte(uint8_t input, struct iio_channel_info *info)
+static void print1byte(uint8_t input, struct iio_channel_info *info)
 {
 	/*
 	 * Shift before conversion to avoid sign extension
@@ -85,7 +87,7 @@ void print1byte(uint8_t input, struct iio_channel_info *info)
 	}
 }
 
-void print2byte(uint16_t input, struct iio_channel_info *info)
+static void print2byte(uint16_t input, struct iio_channel_info *info)
 {
 	/* First swap if incorrect endian */
 	if (info->be)
@@ -108,7 +110,7 @@ void print2byte(uint16_t input, struct iio_channel_info *info)
 	}
 }
 
-void print4byte(uint32_t input, struct iio_channel_info *info)
+static void print4byte(uint32_t input, struct iio_channel_info *info)
 {
 	/* First swap if incorrect endian */
 	if (info->be)
@@ -131,7 +133,7 @@ void print4byte(uint32_t input, struct iio_channel_info *info)
 	}
 }
 
-void print8byte(uint64_t input, struct iio_channel_info *info)
+static void print8byte(uint64_t input, struct iio_channel_info *info)
 {
 	/* First swap if incorrect endian */
 	if (info->be)
@@ -167,9 +169,8 @@ void print8byte(uint64_t input, struct iio_channel_info *info)
  *			      to fill the location offsets.
  * @num_channels:	number of channels
  **/
-void process_scan(char *data,
-		  struct iio_channel_info *channels,
-		  int num_channels)
+static void process_scan(char *data, struct iio_channel_info *channels,
+			 int num_channels)
 {
 	int k;
 
@@ -198,7 +199,7 @@ void process_scan(char *data,
 	printf("\n");
 }
 
-static int enable_disable_all_channels(char *dev_dir_name, int enable)
+static int enable_disable_all_channels(char *dev_dir_name, int buffer_idx, int enable)
 {
 	const struct dirent *ent;
 	char scanelemdir[256];
@@ -206,7 +207,7 @@ static int enable_disable_all_channels(char *dev_dir_name, int enable)
 	int ret;
 
 	snprintf(scanelemdir, sizeof(scanelemdir),
-		 FORMAT_SCAN_ELEMENTS_DIR, dev_dir_name);
+		 FORMAT_SCAN_ELEMENTS_DIR, dev_dir_name, buffer_idx);
 	scanelemdir[sizeof(scanelemdir)-1] = '\0';
 
 	dp = opendir(scanelemdir);
@@ -238,12 +239,13 @@ static int enable_disable_all_channels(char *dev_dir_name, int enable)
 	return 0;
 }
 
-void print_usage(void)
+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"
+		"  -b <n>     The buffer which to open (by index), default 0\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"
@@ -257,12 +259,13 @@ void print_usage(void)
 		"  -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;
+static enum autochan autochannels = AUTOCHANNELS_DISABLED;
+static char *dev_dir_name = NULL;
+static char *buf_dir_name = NULL;
+static int buffer_idx = 0;
+static bool current_trigger_set = false;
 
-void cleanup(void)
+static void cleanup(void)
 {
 	int ret;
 
@@ -287,21 +290,21 @@ void cleanup(void)
 
 	/* Disable channels if auto-enabled */
 	if (dev_dir_name && autochannels == AUTOCHANNELS_ACTIVE) {
-		ret = enable_disable_all_channels(dev_dir_name, 0);
+		ret = enable_disable_all_channels(dev_dir_name, buffer_idx, 0);
 		if (ret)
 			fprintf(stderr, "Failed to disable all channels\n");
 		autochannels = AUTOCHANNELS_DISABLED;
 	}
 }
 
-void sig_handler(int signum)
+static void sig_handler(int signum)
 {
 	fprintf(stderr, "Caught signal %d\n", signum);
 	cleanup();
 	exit(-signum);
 }
 
-void register_cleanup(void)
+static void register_cleanup(void)
 {
 	struct sigaction sa = { .sa_handler = sig_handler };
 	const int signums[] = { SIGINT, SIGTERM, SIGABRT };
@@ -334,7 +337,9 @@ int main(int argc, char **argv)
 	unsigned long long j;
 	unsigned long toread;
 	int ret, c;
-	int fp = -1;
+	struct stat st;
+	int fd = -1;
+	int buf_fd = -1;
 
 	int num_channels = 0;
 	char *trigger_name = NULL, *device_name = NULL;
@@ -353,7 +358,7 @@ int main(int argc, char **argv)
 
 	register_cleanup();
 
-	while ((c = getopt_long(argc, argv, "aAc:egl:n:N:t:T:w:?", longopts,
+	while ((c = getopt_long(argc, argv, "aAb:c:egl:n:N:t:T:w:?", longopts,
 				NULL)) != -1) {
 		switch (c) {
 		case 'a':
@@ -362,7 +367,20 @@ int main(int argc, char **argv)
 		case 'A':
 			autochannels = AUTOCHANNELS_ENABLED;
 			force_autochannels = true;
-			break;	
+			break;
+		case 'b':
+			errno = 0;
+			buffer_idx = strtoll(optarg, &dummy, 10);
+			if (errno) {
+				ret = -errno;
+				goto error;
+			}
+			if (buffer_idx < 0) {
+				ret = -ERANGE;
+				goto error;
+			}
+
+			break;
 		case 'c':
 			errno = 0;
 			num_loops = strtoll(optarg, &dummy, 10);
@@ -519,7 +537,7 @@ int main(int argc, char **argv)
 	 * Parse the files in scan_elements to identify what channels are
 	 * present
 	 */
-	ret = build_channel_array(dev_dir_name, &channels, &num_channels);
+	ret = build_channel_array(dev_dir_name, buffer_idx, &channels, &num_channels);
 	if (ret) {
 		fprintf(stderr, "Problem reading scan element information\n"
 			"diag %s\n", dev_dir_name);
@@ -536,7 +554,7 @@ int main(int argc, char **argv)
 	    (autochannels == AUTOCHANNELS_ENABLED && force_autochannels)) {
 		fprintf(stderr, "Enabling all channels\n");
 
-		ret = enable_disable_all_channels(dev_dir_name, 1);
+		ret = enable_disable_all_channels(dev_dir_name, buffer_idx, 1);
 		if (ret) {
 			fprintf(stderr, "Failed to enable all channels\n");
 			goto error;
@@ -545,7 +563,7 @@ int main(int argc, char **argv)
 		/* This flags that we need to disable the channels again */
 		autochannels = AUTOCHANNELS_ACTIVE;
 
-		ret = build_channel_array(dev_dir_name, &channels,
+		ret = build_channel_array(dev_dir_name, buffer_idx, &channels,
 					  &num_channels);
 		if (ret) {
 			fprintf(stderr, "Problem reading scan element "
@@ -566,7 +584,7 @@ int main(int argc, char **argv)
 		fprintf(stderr, "Enable channels manually in "
 			FORMAT_SCAN_ELEMENTS_DIR
 			"/*_en or pass -a to autoenable channels and "
-			"try again.\n", dev_dir_name);
+			"try again.\n", dev_dir_name, buffer_idx);
 		ret = -ENOENT;
 		goto error;
 	}
@@ -577,12 +595,25 @@ int main(int argc, char **argv)
 	 * be built rather than found.
 	 */
 	ret = asprintf(&buf_dir_name,
-		       "%siio:device%d/buffer", iio_dir, dev_num);
+		       "%siio:device%d/buffer%d", iio_dir, dev_num, buffer_idx);
 	if (ret < 0) {
 		ret = -ENOMEM;
 		goto error;
 	}
 
+	if (stat(buf_dir_name, &st)) {
+		fprintf(stderr, "Could not stat() '%s', got error %d: %s\n",
+			buf_dir_name, errno, strerror(errno));
+		ret = -errno;
+		goto error;
+	}
+
+	if (!S_ISDIR(st.st_mode)) {
+		fprintf(stderr, "File '%s' is not a directory\n", buf_dir_name);
+		ret = -EFAULT;
+		goto error;
+	}
+
 	if (!notrigger) {
 		printf("%s %s\n", dev_dir_name, trigger_name);
 		/*
@@ -599,6 +630,35 @@ int main(int argc, char **argv)
 		}
 	}
 
+	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 */
+	fd = open(buffer_access, O_RDONLY | O_NONBLOCK);
+	if (fd == -1) { /* TODO: If it isn't there make the node */
+		ret = -errno;
+		fprintf(stderr, "Failed to open %s\n", buffer_access);
+		goto error;
+	}
+
+	/* specify for which buffer index we want an FD */
+	buf_fd = buffer_idx;
+
+	ret = ioctl(fd, IIO_BUFFER_GET_FD_IOCTL, &buf_fd);
+	if (ret == -1 || buf_fd == -1) {
+		ret = -errno;
+		if (ret == -ENODEV || ret == -EINVAL)
+			fprintf(stderr,
+				"Device does not have this many buffers\n");
+		else
+			fprintf(stderr, "Failed to retrieve buffer fd\n");
+
+		goto error;
+	}
+
 	/* Setup ring buffer parameters */
 	ret = write_sysfs_int("length", buf_dir_name, buf_len);
 	if (ret < 0)
@@ -608,7 +668,8 @@ int main(int argc, char **argv)
 	ret = write_sysfs_int("enable", buf_dir_name, 1);
 	if (ret < 0) {
 		fprintf(stderr,
-			"Failed to enable buffer: %s\n", strerror(-ret));
+			"Failed to enable buffer '%s': %s\n",
+			buf_dir_name, strerror(-ret));
 		goto error;
 	}
 
@@ -619,24 +680,30 @@ int main(int argc, char **argv)
 		goto error;
 	}
 
-	ret = asprintf(&buffer_access, "/dev/iio:device%d", dev_num);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error;
+	/**
+	 * This check is being done here for sanity reasons, however it
+	 * should be omitted under normal operation.
+	 * If this is buffer0, we check that we get EBUSY after this point.
+	 */
+	if (buffer_idx == 0) {
+		errno = 0;
+		read_size = read(fd, data, 1);
+		if (read_size > -1 || errno != EBUSY) {
+			ret = -EFAULT;
+			perror("Reading from '%s' should not be possible after ioctl()");
+			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;
-	}
+	/* close now the main chardev FD and let the buffer FD work */
+	if (close(fd) == -1)
+		perror("Failed to close character device file");
+	fd = -1;
 
 	for (j = 0; j < num_loops || num_loops < 0; j++) {
 		if (!noevents) {
 			struct pollfd pfd = {
-				.fd = fp,
+				.fd = buf_fd,
 				.events = POLLIN,
 			};
 
@@ -654,7 +721,7 @@ int main(int argc, char **argv)
 			toread = 64;
 		}
 
-		read_size = read(fp, data, toread * scan_size);
+		read_size = read(buf_fd, data, toread * scan_size);
 		if (read_size < 0) {
 			if (errno == EAGAIN) {
 				fprintf(stderr, "nothing available\n");
@@ -671,7 +738,9 @@ int main(int argc, char **argv)
 error:
 	cleanup();
 
-	if (fp >= 0 && close(fp) == -1)
+	if (fd >= 0 && close(fd) == -1)
+		perror("Failed to close character device");
+	if (buf_fd >= 0 && close(buf_fd) == -1)
 		perror("Failed to close buffer");
 	free(buffer_access);
 	free(data);
diff --git a/tools/iio/iio_utils.c b/tools/iio/iio_utils.c
index 7399eb7f1378..aadee6d34c74 100644
--- a/tools/iio/iio_utils.c
+++ b/tools/iio/iio_utils.c
@@ -77,15 +77,17 @@ int iioutils_break_up_name(const char *full_name, char **generic_name)
  * @mask: output a bit mask for the raw data
  * @be: output if data in big endian
  * @device_dir: the IIO device directory
+ * @buffer_idx: the IIO buffer index
  * @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)
+static int iioutils_get_type(unsigned int *is_signed, unsigned int *bytes,
+			     unsigned int *bits_used, unsigned int *shift,
+			     uint64_t *mask, unsigned int *be,
+			     const char *device_dir, int buffer_idx,
+			     const char *name, const char *generic_name)
 {
 	FILE *sysfsfp;
 	int ret;
@@ -95,7 +97,7 @@ int iioutils_get_type(unsigned *is_signed, unsigned *bytes, unsigned *bits_used,
 	unsigned padint;
 	const struct dirent *ent;
 
-	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
+	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir, buffer_idx);
 	if (ret < 0)
 		return -ENOMEM;
 
@@ -303,12 +305,13 @@ void bsort_channel_array_by_index(struct iio_channel_info *ci_array, int cnt)
 /**
  * build_channel_array() - function to figure out what channels are present
  * @device_dir: the IIO device directory in sysfs
+ * @buffer_idx: the IIO buffer for this channel array
  * @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,
+int build_channel_array(const char *device_dir, int buffer_idx,
 			struct iio_channel_info **ci_array, int *counter)
 {
 	DIR *dp;
@@ -321,7 +324,7 @@ int build_channel_array(const char *device_dir,
 	char *filename;
 
 	*counter = 0;
-	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
+	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir, buffer_idx);
 	if (ret < 0)
 		return -ENOMEM;
 
@@ -502,6 +505,7 @@ int build_channel_array(const char *device_dir,
 						&current->mask,
 						&current->be,
 						device_dir,
+						buffer_idx,
 						current->name,
 						current->generic_name);
 			if (ret < 0)
diff --git a/tools/iio/iio_utils.h b/tools/iio/iio_utils.h
index 74bde4fde2c8..663c94a6c705 100644
--- a/tools/iio/iio_utils.h
+++ b/tools/iio/iio_utils.h
@@ -12,7 +12,8 @@
 /* Made up value to limit allocation sizes */
 #define IIO_MAX_NAME_LENGTH 64
 
-#define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
+#define FORMAT_SCAN_ELEMENTS_DIR "%s/buffer%d"
+#define FORMAT_EVENTS_DIR "%s/events"
 #define FORMAT_TYPE_FILE "%s_type"
 
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
@@ -57,15 +58,11 @@ static inline int iioutils_check_suffix(const char *str, const char *suffix)
 }
 
 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_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);
-int build_channel_array(const char *device_dir,
+int build_channel_array(const char *device_dir, int buffer_idx,
 			struct iio_channel_info **ci_array, int *counter);
 int find_type_by_name(const char *name, const char *type);
 int write_sysfs_int(const char *filename, const char *basedir, int val);