Message-ID: <alpine.LNX.2.00.1206141527230.8644@pobox.suse.cz>
Date:	Thu, 14 Jun 2012 15:28:18 +0200 (CEST)
From:	Jiri Kosina <jkosina@...e.cz>
To:	Jonathan Cameron <jic23@....ac.uk>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:	linux-iio@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH] iio: let the doc follow core code move

As the IIO core code has been moved out of staging, let the appropriate 
documentation appear in Documentation/iio (which is what 
drivers/iio/Kconfig suggests as a location to look for it anyway).

Signed-off-by: Jiri Kosina <jkosina@...e.cz>
---
 Documentation/iio/device.txt                       |   81 +++
 Documentation/iio/generic_buffer.c                 |  329 ++++++++++
 Documentation/iio/iio_event_monitor.c              |  241 ++++++++
 Documentation/iio/iio_utils.h                      |  639 ++++++++++++++++++++
 Documentation/iio/inkernel.txt                     |   58 ++
 Documentation/iio/overview.txt                     |   57 ++
 Documentation/iio/ring.txt                         |   47 ++
 drivers/staging/iio/Documentation/device.txt       |   81 ---
 drivers/staging/iio/Documentation/generic_buffer.c |  329 ----------
 .../staging/iio/Documentation/iio_event_monitor.c  |  241 --------
 drivers/staging/iio/Documentation/iio_utils.h      |  639 --------------------
 drivers/staging/iio/Documentation/inkernel.txt     |   58 --
 drivers/staging/iio/Documentation/overview.txt     |   57 --
 drivers/staging/iio/Documentation/ring.txt         |   47 --
 14 files changed, 1452 insertions(+), 1452 deletions(-)
 create mode 100644 Documentation/iio/device.txt
 create mode 100644 Documentation/iio/generic_buffer.c
 create mode 100644 Documentation/iio/iio_event_monitor.c
 create mode 100644 Documentation/iio/iio_utils.h
 create mode 100644 Documentation/iio/inkernel.txt
 create mode 100644 Documentation/iio/overview.txt
 create mode 100644 Documentation/iio/ring.txt
 delete mode 100644 drivers/staging/iio/Documentation/device.txt
 delete mode 100644 drivers/staging/iio/Documentation/generic_buffer.c
 delete mode 100644 drivers/staging/iio/Documentation/iio_event_monitor.c
 delete mode 100644 drivers/staging/iio/Documentation/iio_utils.h
 delete mode 100644 drivers/staging/iio/Documentation/inkernel.txt
 delete mode 100644 drivers/staging/iio/Documentation/overview.txt
 delete mode 100644 drivers/staging/iio/Documentation/ring.txt

diff --git a/Documentation/iio/device.txt b/Documentation/iio/device.txt
new file mode 100644
index 0000000..0338c7c
--- /dev/null
+++ b/Documentation/iio/device.txt
@@ -0,0 +1,81 @@
+IIO Device drivers
+
+This is not intended to provide a comprehensive guide to writing an
+IIO device driver.  For further information see the drivers within the
+subsystem.
+
+The crucial structure for device drivers in iio is iio_dev.
+
+First allocate one using:
+
+struct iio_dev *indio_dev = iio_device_alloc(sizeof(struct chip_state));
+where chip_state is a structure of local state data for this instance of
+the chip.
+
+That data can be accessed using iio_priv(struct iio_dev *)
+
+Then fill in the following:
+
+- indio_dev->dev.parent
+	Struct device associated with the underlying hardware.
+- indio_dev->name
+	Name of the device being driven - made available as the name
+	attribute in sysfs.
+
+- indio_dev->info
+	pointer to a structure with elements that tend to be fixed for
+	large sets of different parts supported by a given driver.
+	This contains:
+	* info->driver_module:
+		Set to THIS_MODULE. Used to ensure correct ownership
+		of various resources allocate by the core.
+	* info->num_interrupt_lines:
+		Number of event triggering hardware lines the device has.
+	* info->event_attrs:
+		Attributes used to enable / disable hardware events.
+	* info->attrs:
+		General device attributes. Typically used for the weird
+		and the wonderful bits not covered by the channel specification.
+	* info->read_raw:
+		Raw data reading function. Used for both raw channel access
+		and for associate parameters such as offsets and scales.
+	* info->write_raw:
+		Raw value writing function. Used for writable device values such
+		as DAC values and caliboffset.
+	* info->read_event_config:
+		Typically only set if there are some interrupt lines.  This
+		is used to read if an on sensor event detector is enabled.
+	* info->write_event_config:
+		Enable / disable an on sensor event detector.
+	* info->read_event_value:
+		Read value associated with on sensor event detectors. Note that
+		the meaning of the returned value is dependent on the event
+		type.
+	* info->write_event_value:
+		Write the value associated with on sensor event detectors. E.g.
+		a threshold above which an interrupt occurs.  Note that the
+		meaning of the value to be set is event type dependant.
+
+- indio_dev->modes:
+	Specify whether direct access and / or ring buffer access is supported.
+- indio_dev->ring:
+	An optional associated buffer.
+- indio_dev->pollfunc:
+	Poll function related elements. This controls what occurs when a trigger
+	to which this device is attached sends an event.
+- indio_dev->channels:
+	Specification of device channels. Most attributes etc are built
+	form this spec.
+- indio_dev->num_channels:
+	How many channels are there?
+
+Once these are set up, a call to iio_device_register(indio_dev),
+will register the device with the iio core.
+
+Worth noting here is that, if a ring buffer is to be used, it can be
+allocated prior to registering the device with the iio-core, but must
+be registered afterwards (otherwise the whole parentage of devices
+gets confused)
+
+On remove, iio_device_unregister(indio_dev) will remove the device from
+the core, and iio_device_free will clean up.
diff --git a/Documentation/iio/generic_buffer.c b/Documentation/iio/generic_buffer.c
new file mode 100644
index 0000000..bf55335
--- /dev/null
+++ b/Documentation/iio/generic_buffer.c
@@ -0,0 +1,329 @@
+/* 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 <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 "iio_utils.h"
+
+/**
+ * size_from_channelarray() - calculate the storage size of a scan
+ * @channels: the channel info array
+ * @num_channels: size of the channel info array
+ *
+ * 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 = 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  ", val,
+		       (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
+ * @infoarray:		information about the channels. Note
+ *  size_from_channelarray must have been called first to fill the
+ *  location offsets.
+ * @num_channels:	the number of active channels
+ **/
+void process_scan(char *data,
+		  struct iio_channel_info *infoarray,
+		  int num_channels)
+{
+	int k;
+	for (k = 0; k < num_channels; k++)
+		switch (infoarray[k].bytes) {
+			/* only a few cases implemented so far */
+		case 2:
+			print2byte(*(uint16_t *)(data + infoarray[k].location),
+				   &infoarray[k]);
+			break;
+		case 8:
+			if (infoarray[k].is_signed) {
+				int64_t val = *(int64_t *)
+					(data +
+					 infoarray[k].location);
+				if ((val >> infoarray[k].bits_used) & 1)
+					val = (val & infoarray[k].mask) |
+						~infoarray[k].mask;
+				/* special case for timestamp */
+				if (infoarray[k].scale == 1.0f &&
+				    infoarray[k].offset == 0.0f)
+					printf(" %lld", val);
+				else
+					printf("%05f ", ((float)val +
+							 infoarray[k].offset)*
+					       infoarray[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;
+
+	FILE *fp_ev;
+	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;
+	char *dummy;
+
+	struct iio_channel_info *infoarray;
+
+	while ((c = getopt(argc, argv, "l:w:c:et:n:")) != -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 '?':
+			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 (trigger_name == NULL) {
+		/*
+		 * Build the trigger name. If it is device associated it's
+		 * 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);
+
+	/*
+	 * Parse the files in scan_elements to identify what channels are
+	 * present
+	 */
+	ret = build_channel_array(dev_dir_name, &infoarray, &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;
+	}
+	printf("%s %s\n", dev_dir_name, trigger_name);
+	/* Set the device trigger to be the data rdy 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(infoarray, 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 == -EAGAIN) {
+			printf("nothing available\n");
+			continue;
+		}
+		for (i = 0; i < read_size/scan_size; i++)
+			process_scan(data + scan_size*i,
+				     infoarray,
+				     num_channels);
+	}
+
+	/* Stop the ring buffer */
+	ret = write_sysfs_int("enable", buf_dir_name, 0);
+	if (ret < 0)
+		goto error_close_buffer_access;
+
+	/* Disconnect from 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;
+}
diff --git a/Documentation/iio/iio_event_monitor.c b/Documentation/iio/iio_event_monitor.c
new file mode 100644
index 0000000..2227584
--- /dev/null
+++ b/Documentation/iio/iio_event_monitor.c
@@ -0,0 +1,241 @@
+/* Industrialio event test code.
+ *
+ * Copyright (c) 2011-2012 Lars-Peter Clausen <lars@...afoo.de>
+ *
+ * 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.
+ *
+ * Usage:
+ *	iio_event_monitor <device_name>
+ *
+ */
+
+#define _GNU_SOURCE
+
+#include <unistd.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <poll.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include "iio_utils.h"
+#include <linux/iio/events.h>
+
+static const char * const iio_chan_type_name_spec[] = {
+	[IIO_VOLTAGE] = "voltage",
+	[IIO_CURRENT] = "current",
+	[IIO_POWER] = "power",
+	[IIO_ACCEL] = "accel",
+	[IIO_ANGL_VEL] = "anglvel",
+	[IIO_MAGN] = "magn",
+	[IIO_LIGHT] = "illuminance",
+	[IIO_INTENSITY] = "intensity",
+	[IIO_PROXIMITY] = "proximity",
+	[IIO_TEMP] = "temp",
+	[IIO_INCLI] = "incli",
+	[IIO_ROT] = "rot",
+	[IIO_ANGL] = "angl",
+	[IIO_TIMESTAMP] = "timestamp",
+	[IIO_CAPACITANCE] = "capacitance",
+};
+
+static const char * const iio_ev_type_text[] = {
+	[IIO_EV_TYPE_THRESH] = "thresh",
+	[IIO_EV_TYPE_MAG] = "mag",
+	[IIO_EV_TYPE_ROC] = "roc",
+	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
+	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
+};
+
+static const char * const iio_ev_dir_text[] = {
+	[IIO_EV_DIR_EITHER] = "either",
+	[IIO_EV_DIR_RISING] = "rising",
+	[IIO_EV_DIR_FALLING] = "falling"
+};
+
+static const char * const iio_modifier_names[] = {
+	[IIO_MOD_X] = "x",
+	[IIO_MOD_Y] = "y",
+	[IIO_MOD_Z] = "z",
+	[IIO_MOD_LIGHT_BOTH] = "both",
+	[IIO_MOD_LIGHT_IR] = "ir",
+};
+
+static bool event_is_known(struct iio_event_data *event)
+{
+	enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
+	enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
+	enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
+	enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);
+
+	switch (type) {
+	case IIO_VOLTAGE:
+	case IIO_CURRENT:
+	case IIO_POWER:
+	case IIO_ACCEL:
+	case IIO_ANGL_VEL:
+	case IIO_MAGN:
+	case IIO_LIGHT:
+	case IIO_INTENSITY:
+	case IIO_PROXIMITY:
+	case IIO_TEMP:
+	case IIO_INCLI:
+	case IIO_ROT:
+	case IIO_ANGL:
+	case IIO_TIMESTAMP:
+	case IIO_CAPACITANCE:
+		break;
+	default:
+		return false;
+	}
+
+	switch (mod) {
+	case IIO_NO_MOD:
+	case IIO_MOD_X:
+	case IIO_MOD_Y:
+	case IIO_MOD_Z:
+	case IIO_MOD_LIGHT_BOTH:
+	case IIO_MOD_LIGHT_IR:
+		break;
+	default:
+		return false;
+	}
+
+	switch (ev_type) {
+	case IIO_EV_TYPE_THRESH:
+	case IIO_EV_TYPE_MAG:
+	case IIO_EV_TYPE_ROC:
+	case IIO_EV_TYPE_THRESH_ADAPTIVE:
+	case IIO_EV_TYPE_MAG_ADAPTIVE:
+		break;
+	default:
+		return false;
+	}
+
+	switch (dir) {
+	case IIO_EV_DIR_EITHER:
+	case IIO_EV_DIR_RISING:
+	case IIO_EV_DIR_FALLING:
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+static void print_event(struct iio_event_data *event)
+{
+	enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
+	enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
+	enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
+	enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);
+	int chan = IIO_EVENT_CODE_EXTRACT_CHAN(event->id);
+	int chan2 = IIO_EVENT_CODE_EXTRACT_CHAN2(event->id);
+	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);
+		return;
+	}
+
+	printf("Event: time: %lld, ", event->timestamp);
+
+	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 (diff && chan >= 0 && chan2 >= 0)
+		printf("channel: %d-%d, ", chan, chan2);
+	else if (chan >= 0)
+		printf("channel: %d, ", chan);
+
+	printf("evtype: %s, direction: %s\n",
+		iio_ev_type_text[ev_type],
+		iio_ev_dir_text[dir]);
+}
+
+int main(int argc, char **argv)
+{
+	struct iio_event_data event;
+	const char *device_name;
+	char *chrdev_name;
+	int ret;
+	int dev_num;
+	int fd, event_fd;
+
+	if (argc <= 1) {
+		printf("Usage: %s <device_name>\n", argv[0]);
+		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",
+			device_name, dev_num);
+		ret = asprintf(&chrdev_name, "/dev/iio:device%d", dev_num);
+		if (ret < 0) {
+			ret = -ENOMEM;
+			goto error_ret;
+		}
+	} else {
+		/* If we can't find a IIO device by name assume device_name is a
+		   IIO chrdev */
+		chrdev_name = strdup(device_name);
+	}
+
+	fd = open(chrdev_name, 0);
+	if (fd == -1) {
+		fprintf(stdout, "Failed to open %s\n", chrdev_name);
+		ret = -errno;
+		goto error_free_chrdev_name;
+	}
+
+	ret = ioctl(fd, IIO_GET_EVENT_FD_IOCTL, &event_fd);
+
+	close(fd);
+
+	if (ret == -1 || event_fd == -1) {
+		fprintf(stdout, "Failed to retrieve event fd\n");
+		ret = -errno;
+		goto error_free_chrdev_name;
+	}
+
+	while (true) {
+		ret = read(event_fd, &event, sizeof(event));
+		if (ret == -1) {
+			if (errno == EAGAIN) {
+				printf("nothing available\n");
+				continue;
+			} else {
+				perror("Failed to read event from device");
+				ret = -errno;
+				break;
+			}
+		}
+
+		print_event(&event);
+	}
+
+	close(event_fd);
+error_free_chrdev_name:
+	free(chrdev_name);
+error_ret:
+	return ret;
+}
diff --git a/Documentation/iio/iio_utils.h b/Documentation/iio/iio_utils.h
new file mode 100644
index 0000000..6f3a392
--- /dev/null
+++ b/Documentation/iio/iio_utils.h
@@ -0,0 +1,639 @@
+/* IIO - useful set of util functionality
+ *
+ * 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.
+ */
+
+/* Made up value to limit allocation sizes */
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <dirent.h>
+
+#define IIO_MAX_NAME_LENGTH 30
+
+#define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
+#define FORMAT_TYPE_FILE "%s_type"
+
+const char *iio_dir = "/sys/bus/iio/devices/";
+
+/**
+ * iioutils_break_up_name() - extract generic name from full channel name
+ * @full_name: the full channel name
+ * @generic_name: the output generic channel name
+ **/
+static int iioutils_break_up_name(const char *full_name,
+				  char **generic_name)
+{
+	char *current;
+	char *w, *r;
+	char *working;
+	current = strdup(full_name);
+	working = strtok(current, "_\0");
+	w = working;
+	r = working;
+
+	while (*r != '\0') {
+		if (!isdigit(*r)) {
+			*w = *r;
+			w++;
+		}
+		r++;
+	}
+	*w = '\0';
+	*generic_name = strdup(working);
+	free(current);
+
+	return 0;
+}
+
+/**
+ * struct iio_channel_info - information about a given channel
+ * @name: channel name
+ * @generic_name: general name for channel type
+ * @scale: scale factor to be applied for conversion to si units
+ * @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
+ * @mask: a bit mask for the raw output
+ * @is_signed: is the raw value stored signed
+ * @enabled: is this channel enabled
+ **/
+struct iio_channel_info {
+	char *name;
+	char *generic_name;
+	float scale;
+	float offset;
+	unsigned index;
+	unsigned bytes;
+	unsigned bits_used;
+	unsigned shift;
+	uint64_t mask;
+	unsigned be;
+	unsigned is_signed;
+	unsigned enabled;
+	unsigned location;
+};
+
+/**
+ * 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
+ * @mask: output a bit mask for the raw data
+ * @be: big endian
+ * @device_dir: the iio device directory
+ * @name: the channel name
+ * @generic_name: the channel type name
+ **/
+inline 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;
+	DIR *dp;
+	char *scan_el_dir, *builtname, *builtname_generic, *filename = 0;
+	char signchar, endianchar;
+	unsigned padint;
+	const struct dirent *ent;
+
+	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	ret = asprintf(&builtname, FORMAT_TYPE_FILE, name);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_free_scan_el_dir;
+	}
+	ret = asprintf(&builtname_generic, FORMAT_TYPE_FILE, generic_name);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_free_builtname;
+	}
+
+	dp = opendir(scan_el_dir);
+	if (dp == NULL) {
+		ret = -errno;
+		goto error_free_builtname_generic;
+	}
+	while (ent = readdir(dp), ent != NULL)
+		/*
+		 * Do we allow devices to override a generic name with
+		 * a specific one?
+		 */
+		if ((strcmp(builtname, ent->d_name) == 0) ||
+		    (strcmp(builtname_generic, ent->d_name) == 0)) {
+			ret = asprintf(&filename,
+				       "%s/%s", scan_el_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				goto error_closedir;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (sysfsfp == NULL) {
+				printf("failed to open %s\n", filename);
+				ret = -errno;
+				goto error_free_filename;
+			}
+
+			ret = fscanf(sysfsfp,
+				     "%ce:%c%u/%u>>%u",
+				     &endianchar,
+				     &signchar,
+				     bits_used,
+				     &padint, shift);
+			if (ret < 0) {
+				printf("failed to pass scan type description\n");
+				return ret;
+			}
+			*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);
+
+			filename = 0;
+		}
+error_free_filename:
+	if (filename)
+		free(filename);
+error_closedir:
+	closedir(dp);
+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;
+}
+
+inline 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;
+	DIR *dp;
+	char *builtname, *builtname_generic;
+	char *filename = NULL;
+	const struct dirent *ent;
+
+	ret = asprintf(&builtname, "%s_%s", name, param_name);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	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) {
+		ret = -errno;
+		goto error_free_builtname_generic;
+	}
+	while (ent = readdir(dp), ent != NULL)
+		if ((strcmp(builtname, ent->d_name) == 0) ||
+		    (strcmp(builtname_generic, ent->d_name) == 0)) {
+			ret = asprintf(&filename,
+				       "%s/%s", device_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				goto error_closedir;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (!sysfsfp) {
+				ret = -errno;
+				goto error_free_filename;
+			}
+			fscanf(sysfsfp, "%f", output);
+			break;
+		}
+error_free_filename:
+	if (filename)
+		free(filename);
+error_closedir:
+	closedir(dp);
+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
+ *
+ **/
+
+inline 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;
+			}
+}
+
+/**
+ * build_channel_array() - function to figure out what channels are present
+ * @device_dir: the IIO device directory in sysfs
+ * @
+ **/
+inline int build_channel_array(const char *device_dir,
+			      struct iio_channel_info **ci_array,
+			      int *counter)
+{
+	DIR *dp;
+	FILE *sysfsfp;
+	int count, temp, i;
+	struct iio_channel_info *current;
+	int ret;
+	const struct dirent *ent;
+	char *scan_el_dir;
+	char *filename;
+
+	*counter = 0;
+	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
+	if (ret < 0) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	dp = opendir(scan_el_dir);
+	if (dp == NULL) {
+		ret = -errno;
+		goto error_free_name;
+	}
+	while (ent = readdir(dp), ent != NULL)
+		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
+			   "_en") == 0) {
+			ret = asprintf(&filename,
+				       "%s/%s", scan_el_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				goto error_close_dir;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (sysfsfp == NULL) {
+				ret = -errno;
+				free(filename);
+				goto error_close_dir;
+			}
+			fscanf(sysfsfp, "%u", &ret);
+			if (ret == 1)
+				(*counter)++;
+			fclose(sysfsfp);
+			free(filename);
+		}
+	*ci_array = malloc(sizeof(**ci_array) * (*counter));
+	if (*ci_array == NULL) {
+		ret = -ENOMEM;
+		goto error_close_dir;
+	}
+	seekdir(dp, 0);
+	count = 0;
+	while (ent = readdir(dp), ent != NULL) {
+		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
+			   "_en") == 0) {
+			current = &(*ci_array)[count++];
+			ret = asprintf(&filename,
+				       "%s/%s", scan_el_dir, ent->d_name);
+			if (ret < 0) {
+				ret = -ENOMEM;
+				/* decrement count to avoid freeing name */
+				count--;
+				goto error_cleanup_array;
+			}
+			sysfsfp = fopen(filename, "r");
+			if (sysfsfp == NULL) {
+				free(filename);
+				ret = -errno;
+				goto error_cleanup_array;
+			}
+			fscanf(sysfsfp, "%u", &current->enabled);
+			fclose(sysfsfp);
+
+			if (!current->enabled) {
+				free(filename);
+				count--;
+				continue;
+			}
+
+			current->scale = 1.0;
+			current->offset = 0;
+			current->name = strndup(ent->d_name,
+						strlen(ent->d_name) -
+						strlen("_en"));
+			if (current->name == NULL) {
+				free(filename);
+				ret = -ENOMEM;
+				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);
+				goto error_cleanup_array;
+			}
+			ret = asprintf(&filename,
+				       "%s/%s_index",
+				       scan_el_dir,
+				       current->name);
+			if (ret < 0) {
+				free(filename);
+				ret = -ENOMEM;
+				goto error_cleanup_array;
+			}
+			sysfsfp = fopen(filename, "r");
+			fscanf(sysfsfp, "%u", &current->index);
+			fclose(sysfsfp);
+			free(filename);
+			/* Find the scale */
+			ret = iioutils_get_param_float(&current->scale,
+						       "scale",
+						       device_dir,
+						       current->name,
+						       current->generic_name);
+			if (ret < 0)
+				goto error_cleanup_array;
+			ret = iioutils_get_param_float(&current->offset,
+						       "offset",
+						       device_dir,
+						       current->name,
+						       current->generic_name);
+			if (ret < 0)
+				goto error_cleanup_array;
+			ret = iioutils_get_type(&current->is_signed,
+						&current->bytes,
+						&current->bits_used,
+						&current->shift,
+						&current->mask,
+						&current->be,
+						device_dir,
+						current->name,
+						current->generic_name);
+		}
+	}
+
+	closedir(dp);
+	/* reorder so that the array is in index order */
+	bsort_channel_array_by_index(ci_array, *counter);
+
+	return 0;
+
+error_cleanup_array:
+	for (i = count - 1;  i >= 0; i--)
+		free((*ci_array)[i].name);
+	free(*ci_array);
+error_close_dir:
+	closedir(dp);
+error_free_name:
+	free(scan_el_dir);
+error_ret:
+	return ret;
+}
+
+/**
+ * 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
+ *
+ * Typical types this is used for are device and trigger.
+ **/
+inline int find_type_by_name(const char *name, const char *type)
+{
+	const struct dirent *ent;
+	int number, numstrlen;
+
+	FILE *nameFile;
+	DIR *dp;
+	char thisname[IIO_MAX_NAME_LENGTH];
+	char *filename;
+
+	dp = opendir(iio_dir);
+	if (dp == NULL) {
+		printf("No industrialio devices available");
+		return -ENODEV;
+	}
+
+	while (ent = readdir(dp), ent != NULL) {
+		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);
+			/* 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)
+					return -ENOMEM;
+				sprintf(filename, "%s%s%d/name",
+					iio_dir,
+					type,
+					number);
+				nameFile = fopen(filename, "r");
+				if (!nameFile)
+					continue;
+				free(filename);
+				fscanf(nameFile, "%s", thisname);
+				if (strcmp(name, thisname) == 0)
+					return number;
+				fclose(nameFile);
+			}
+		}
+	}
+	return -ENODEV;
+}
+
+inline int _write_sysfs_int(char *filename, char *basedir, int val, int verify)
+{
+	int ret;
+	FILE *sysfsfp;
+	int test;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+	if (temp == NULL)
+		return -ENOMEM;
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "w");
+	if (sysfsfp == NULL) {
+		printf("failed to open %s\n", temp);
+		ret = -errno;
+		goto error_free;
+	}
+	fprintf(sysfsfp, "%d", val);
+	fclose(sysfsfp);
+	if (verify) {
+		sysfsfp = fopen(temp, "r");
+		if (sysfsfp == NULL) {
+			printf("failed to open %s\n", temp);
+			ret = -errno;
+			goto error_free;
+		}
+		fscanf(sysfsfp, "%d", &test);
+		if (test != val) {
+			printf("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)
+{
+	return _write_sysfs_int(filename, basedir, val, 0);
+}
+
+int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
+{
+	return _write_sysfs_int(filename, basedir, val, 1);
+}
+
+int _write_sysfs_string(char *filename, char *basedir, 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");
+		return -ENOMEM;
+	}
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "w");
+	if (sysfsfp == NULL) {
+		printf("Could not open %s\n", temp);
+		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");
+			ret = -errno;
+			goto error_free;
+		}
+		fscanf(sysfsfp, "%s", temp);
+		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);
+			ret = -1;
+		}
+	}
+error_free:
+	free(temp);
+
+	return ret;
+}
+
+/**
+ * write_sysfs_string_and_verify() - string write, readback and verify
+ * @filename: name of file to write to
+ * @basedir: the sysfs directory in which the file is to be found
+ * @val: the string to write
+ **/
+int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
+{
+	return _write_sysfs_string(filename, basedir, val, 1);
+}
+
+int write_sysfs_string(char *filename, char *basedir, char *val)
+{
+	return _write_sysfs_string(filename, basedir, val, 0);
+}
+
+int read_sysfs_posint(char *filename, char *basedir)
+{
+	int ret;
+	FILE  *sysfsfp;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+	if (temp == NULL) {
+		printf("Memory allocation failed");
+		return -ENOMEM;
+	}
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "r");
+	if (sysfsfp == NULL) {
+		ret = -errno;
+		goto error_free;
+	}
+	fscanf(sysfsfp, "%d\n", &ret);
+	fclose(sysfsfp);
+error_free:
+	free(temp);
+	return ret;
+}
+
+int read_sysfs_float(char *filename, char *basedir, float *val)
+{
+	float ret = 0;
+	FILE  *sysfsfp;
+	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
+	if (temp == NULL) {
+		printf("Memory allocation failed");
+		return -ENOMEM;
+	}
+	sprintf(temp, "%s/%s", basedir, filename);
+	sysfsfp = fopen(temp, "r");
+	if (sysfsfp == NULL) {
+		ret = -errno;
+		goto error_free;
+	}
+	fscanf(sysfsfp, "%f\n", val);
+	fclose(sysfsfp);
+error_free:
+	free(temp);
+	return ret;
+}
diff --git a/Documentation/iio/inkernel.txt b/Documentation/iio/inkernel.txt
new file mode 100644
index 0000000..a05823e
--- /dev/null
+++ b/Documentation/iio/inkernel.txt
@@ -0,0 +1,58 @@
+Industrial I/O Subsystem in kernel consumers.
+
+The IIO subsystem can act as a layer under other elements of the kernel
+providing a means of obtaining ADC type readings or of driving DAC type
+signals.  The functionality supported will grow as use cases arise.
+
+Describing the channel mapping (iio/machine.h)
+
+Channel associations are described using:
+
+struct iio_map {
+	const char *adc_channel_label;
+	const char *consumer_dev_name;
+	const char *consumer_channel;
+};
+
+adc_channel_label identifies the channel on the IIO device by being
+matched against the datasheet_name field of the iio_chan_spec.
+
+consumer_dev_name allows identification of the consumer device.
+This are then used to find the channel mapping from the consumer device (see
+below).
+
+Finally consumer_channel is a string identifying the channel to the consumer.
+(Perhaps 'battery_voltage' or similar).
+
+An array of these structures is then passed to the IIO driver.
+
+Supporting in kernel interfaces in the driver (driver.h)
+
+The driver must provide datasheet_name values for its channels and
+must pass the iio_map structures and a pointer to its own iio_dev structure
+ on to the core via a call to iio_map_array_register.  On removal,
+iio_map_array_unregister reverses this process.
+
+The result of this is that the IIO core now has all the information needed
+to associate a given channel with the consumer requesting it.
+
+Acting as an IIO consumer (consumer.h)
+
+The consumer first has to obtain an iio_channel structure from the core
+by calling iio_channel_get().  The correct channel is identified by:
+
+* matching dev or dev_name against consumer_dev and consumer_dev_name
+* matching consumer_channel against consumer_channel in the map
+
+There are then a number of functions that can be used to get information
+about this channel such as it's current reading.
+
+e.g.
+iio_st_read_channel_raw() - get a reading
+iio_st_read_channel_type() - get the type of channel
+
+There is also provision for retrieving all of the channels associated
+with a given consumer.  This is useful for generic drivers such as
+iio_hwmon where the number and naming of channels is not known by the
+consumer driver.  To do this, use iio_st_channel_get_all.
+
diff --git a/Documentation/iio/overview.txt b/Documentation/iio/overview.txt
new file mode 100644
index 0000000..afc39ec
--- /dev/null
+++ b/Documentation/iio/overview.txt
@@ -0,0 +1,57 @@
+Overview of IIO
+
+The Industrial I/O subsystem is intended to provide support for devices
+that in some sense are analog to digital converters (ADCs). As many
+actual devices combine some ADCs with digital to analog converters
+(DACs) that functionality is also supported.
+
+The aim is to fill the gap between the somewhat similar hwmon and
+input subsystems.  Hwmon is very much directed at low sample rate
+sensors used in applications such as fan speed control and temperature
+measurement.  Input is, as it's name suggests focused on input
+devices. In some cases there is considerable overlap between these and
+IIO.
+
+A typical device falling into this category would be connected via SPI
+or I2C.
+
+Functionality of IIO
+
+* Basic device registration and handling. This is very similar to
+hwmon with simple polled access to device channels via sysfs.
+
+* Event chrdevs.  These are similar to input in that they provide a
+route to user space for hardware triggered events. Such events include
+threshold detectors, free-fall detectors and more complex action
+detection.  The events themselves are currently very simple with
+merely an event code and a timestamp.  Any data associated with the
+event must be accessed via polling.
+
+Note: A given device may have one or more event channel.  These events are
+turned on or off (if possible) via sysfs interfaces.
+
+* Hardware buffer support.  Some recent sensors have included
+fifo / ring buffers on the sensor chip.  These greatly reduce the load
+on the host CPU by buffering relatively large numbers of data samples
+based on an internal sampling clock. Examples include VTI SCA3000
+series and Analog Device ADXL345 accelerometers.  Each buffer supports
+polling to establish when data is available.
+
+* Trigger and software buffer support. In many data analysis
+applications it it useful to be able to capture data based on some
+external signal (trigger).  These triggers might be a data ready
+signal, a gpio line connected to some external system or an on
+processor periodic interrupt.  A single trigger may initialize data
+capture or reading from a number of sensors.  These triggers are
+used in IIO to fill software buffers acting in a very similar
+fashion to the hardware buffers described above.
+
+Other documentation:
+
+device.txt - elements of a typical device driver.
+
+trigger.txt - elements of a typical trigger driver.
+
+ring.txt - additional elements required for buffer support.
+
+sysfs-bus-iio - abi documentation file.
diff --git a/Documentation/iio/ring.txt b/Documentation/iio/ring.txt
new file mode 100644
index 0000000..e338077
--- /dev/null
+++ b/Documentation/iio/ring.txt
@@ -0,0 +1,47 @@
+Buffer support within IIO
+
+This document is intended as a general overview of the functionality
+a buffer may supply and how it is specified within IIO.  For more
+specific information on a given buffer implementation, see the
+comments in the source code.  Note that some drivers allow buffer
+implementation to be selected at compile time via Kconfig options.
+
+A given buffer implementation typically embeds a struct
+iio_ring_buffer and it is a pointer to this that is provided to the
+IIO core. Access to the embedding structure is typically done via
+container_of functions.
+
+struct iio_ring_buffer contains a struct iio_ring_setup_ops *setup_ops
+which in turn contains the 4 function pointers
+(preenable, postenable, predisable and postdisable).
+These are used to perform device specific steps on either side
+of the core changing it's current mode to indicate that the buffer
+is enabled or disabled (along with enabling triggering etc as appropriate).
+
+Also in struct iio_ring_buffer is a struct iio_ring_access_funcs.
+The function pointers within here are used to allow the core to handle
+as much buffer functionality as possible. Note almost all of these
+are optional.
+
+store_to
+  If possible, push data to the buffer.
+
+read_last
+  If possible, get the most recent scan from the buffer (without removal).
+  This provides polling like functionality whilst the ring buffering is in
+  use without a separate read from the device.
+
+rip_first_n
+  The primary buffer reading function. Note that it may well not return
+  as much data as requested.
+
+request_update
+  If parameters have changed that require reinitialization or configuration of
+  the buffer this will trigger it.
+
+get_bytes_per_datum, set_bytes_per_datum
+  Get/set the number of bytes for a complete scan. (All samples + timestamp)
+
+get_length / set_length
+  Get/set the number of complete scans that may be held by the buffer.
+
diff --git a/drivers/staging/iio/Documentation/device.txt b/drivers/staging/iio/Documentation/device.txt
deleted file mode 100644
index 0338c7c..0000000
--- a/drivers/staging/iio/Documentation/device.txt
+++ /dev/null
@@ -1,81 +0,0 @@
-IIO Device drivers
-
-This is not intended to provide a comprehensive guide to writing an
-IIO device driver.  For further information see the drivers within the
-subsystem.
-
-The crucial structure for device drivers in iio is iio_dev.
-
-First allocate one using:
-
-struct iio_dev *indio_dev = iio_device_alloc(sizeof(struct chip_state));
-where chip_state is a structure of local state data for this instance of
-the chip.
-
-That data can be accessed using iio_priv(struct iio_dev *)
-
-Then fill in the following:
-
-- indio_dev->dev.parent
-	Struct device associated with the underlying hardware.
-- indio_dev->name
-	Name of the device being driven - made available as the name
-	attribute in sysfs.
-
-- indio_dev->info
-	pointer to a structure with elements that tend to be fixed for
-	large sets of different parts supported by a given driver.
-	This contains:
-	* info->driver_module:
-		Set to THIS_MODULE. Used to ensure correct ownership
-		of various resources allocate by the core.
-	* info->num_interrupt_lines:
-		Number of event triggering hardware lines the device has.
-	* info->event_attrs:
-		Attributes used to enable / disable hardware events.
-	* info->attrs:
-		General device attributes. Typically used for the weird
-		and the wonderful bits not covered by the channel specification.
-	* info->read_raw:
-		Raw data reading function. Used for both raw channel access
-		and for associate parameters such as offsets and scales.
-	* info->write_raw:
-		Raw value writing function. Used for writable device values such
-		as DAC values and caliboffset.
-	* info->read_event_config:
-		Typically only set if there are some interrupt lines.  This
-		is used to read if an on sensor event detector is enabled.
-	* info->write_event_config:
-		Enable / disable an on sensor event detector.
-	* info->read_event_value:
-		Read value associated with on sensor event detectors. Note that
-		the meaning of the returned value is dependent on the event
-		type.
-	* info->write_event_value:
-		Write the value associated with on sensor event detectors. E.g.
-		a threshold above which an interrupt occurs.  Note that the
-		meaning of the value to be set is event type dependant.
-
-- indio_dev->modes:
-	Specify whether direct access and / or ring buffer access is supported.
-- indio_dev->ring:
-	An optional associated buffer.
-- indio_dev->pollfunc:
-	Poll function related elements. This controls what occurs when a trigger
-	to which this device is attached sends an event.
-- indio_dev->channels:
-	Specification of device channels. Most attributes etc are built
-	form this spec.
-- indio_dev->num_channels:
-	How many channels are there?
-
-Once these are set up, a call to iio_device_register(indio_dev),
-will register the device with the iio core.
-
-Worth noting here is that, if a ring buffer is to be used, it can be
-allocated prior to registering the device with the iio-core, but must
-be registered afterwards (otherwise the whole parentage of devices
-gets confused)
-
-On remove, iio_device_unregister(indio_dev) will remove the device from
-the core, and iio_device_free will clean up.
diff --git a/drivers/staging/iio/Documentation/generic_buffer.c b/drivers/staging/iio/Documentation/generic_buffer.c
deleted file mode 100644
index bf55335..0000000
--- a/drivers/staging/iio/Documentation/generic_buffer.c
+++ /dev/null
@@ -1,329 +0,0 @@
-/* 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 <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 "iio_utils.h"
-
-/**
- * size_from_channelarray() - calculate the storage size of a scan
- * @channels: the channel info array
- * @num_channels: size of the channel info array
- *
- * 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 = 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  ", val,
-		       (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
- * @infoarray:		information about the channels. Note
- *  size_from_channelarray must have been called first to fill the
- *  location offsets.
- * @num_channels:	the number of active channels
- **/
-void process_scan(char *data,
-		  struct iio_channel_info *infoarray,
-		  int num_channels)
-{
-	int k;
-	for (k = 0; k < num_channels; k++)
-		switch (infoarray[k].bytes) {
-			/* only a few cases implemented so far */
-		case 2:
-			print2byte(*(uint16_t *)(data + infoarray[k].location),
-				   &infoarray[k]);
-			break;
-		case 8:
-			if (infoarray[k].is_signed) {
-				int64_t val = *(int64_t *)
-					(data +
-					 infoarray[k].location);
-				if ((val >> infoarray[k].bits_used) & 1)
-					val = (val & infoarray[k].mask) |
-						~infoarray[k].mask;
-				/* special case for timestamp */
-				if (infoarray[k].scale == 1.0f &&
-				    infoarray[k].offset == 0.0f)
-					printf(" %lld", val);
-				else
-					printf("%05f ", ((float)val +
-							 infoarray[k].offset)*
-					       infoarray[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;
-
-	FILE *fp_ev;
-	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;
-	char *dummy;
-
-	struct iio_channel_info *infoarray;
-
-	while ((c = getopt(argc, argv, "l:w:c:et:n:")) != -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 '?':
-			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 (trigger_name == NULL) {
-		/*
-		 * Build the trigger name. If it is device associated it's
-		 * 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);
-
-	/*
-	 * Parse the files in scan_elements to identify what channels are
-	 * present
-	 */
-	ret = build_channel_array(dev_dir_name, &infoarray, &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;
-	}
-	printf("%s %s\n", dev_dir_name, trigger_name);
-	/* Set the device trigger to be the data rdy 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(infoarray, 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 == -EAGAIN) {
-			printf("nothing available\n");
-			continue;
-		}
-		for (i = 0; i < read_size/scan_size; i++)
-			process_scan(data + scan_size*i,
-				     infoarray,
-				     num_channels);
-	}
-
-	/* Stop the ring buffer */
-	ret = write_sysfs_int("enable", buf_dir_name, 0);
-	if (ret < 0)
-		goto error_close_buffer_access;
-
-	/* Disconnect from 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;
-}
diff --git a/drivers/staging/iio/Documentation/iio_event_monitor.c b/drivers/staging/iio/Documentation/iio_event_monitor.c
deleted file mode 100644
index 2227584..0000000
--- a/drivers/staging/iio/Documentation/iio_event_monitor.c
+++ /dev/null
@@ -1,241 +0,0 @@
-/* Industrialio event test code.
- *
- * Copyright (c) 2011-2012 Lars-Peter Clausen <lars@...afoo.de>
- *
- * 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.
- *
- * Usage:
- *	iio_event_monitor <device_name>
- *
- */
-
-#define _GNU_SOURCE
-
-#include <unistd.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <errno.h>
-#include <string.h>
-#include <poll.h>
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include "iio_utils.h"
-#include <linux/iio/events.h>
-
-static const char * const iio_chan_type_name_spec[] = {
-	[IIO_VOLTAGE] = "voltage",
-	[IIO_CURRENT] = "current",
-	[IIO_POWER] = "power",
-	[IIO_ACCEL] = "accel",
-	[IIO_ANGL_VEL] = "anglvel",
-	[IIO_MAGN] = "magn",
-	[IIO_LIGHT] = "illuminance",
-	[IIO_INTENSITY] = "intensity",
-	[IIO_PROXIMITY] = "proximity",
-	[IIO_TEMP] = "temp",
-	[IIO_INCLI] = "incli",
-	[IIO_ROT] = "rot",
-	[IIO_ANGL] = "angl",
-	[IIO_TIMESTAMP] = "timestamp",
-	[IIO_CAPACITANCE] = "capacitance",
-};
-
-static const char * const iio_ev_type_text[] = {
-	[IIO_EV_TYPE_THRESH] = "thresh",
-	[IIO_EV_TYPE_MAG] = "mag",
-	[IIO_EV_TYPE_ROC] = "roc",
-	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
-	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
-};
-
-static const char * const iio_ev_dir_text[] = {
-	[IIO_EV_DIR_EITHER] = "either",
-	[IIO_EV_DIR_RISING] = "rising",
-	[IIO_EV_DIR_FALLING] = "falling"
-};
-
-static const char * const iio_modifier_names[] = {
-	[IIO_MOD_X] = "x",
-	[IIO_MOD_Y] = "y",
-	[IIO_MOD_Z] = "z",
-	[IIO_MOD_LIGHT_BOTH] = "both",
-	[IIO_MOD_LIGHT_IR] = "ir",
-};
-
-static bool event_is_known(struct iio_event_data *event)
-{
-	enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
-	enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
-	enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
-	enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);
-
-	switch (type) {
-	case IIO_VOLTAGE:
-	case IIO_CURRENT:
-	case IIO_POWER:
-	case IIO_ACCEL:
-	case IIO_ANGL_VEL:
-	case IIO_MAGN:
-	case IIO_LIGHT:
-	case IIO_INTENSITY:
-	case IIO_PROXIMITY:
-	case IIO_TEMP:
-	case IIO_INCLI:
-	case IIO_ROT:
-	case IIO_ANGL:
-	case IIO_TIMESTAMP:
-	case IIO_CAPACITANCE:
-		break;
-	default:
-		return false;
-	}
-
-	switch (mod) {
-	case IIO_NO_MOD:
-	case IIO_MOD_X:
-	case IIO_MOD_Y:
-	case IIO_MOD_Z:
-	case IIO_MOD_LIGHT_BOTH:
-	case IIO_MOD_LIGHT_IR:
-		break;
-	default:
-		return false;
-	}
-
-	switch (ev_type) {
-	case IIO_EV_TYPE_THRESH:
-	case IIO_EV_TYPE_MAG:
-	case IIO_EV_TYPE_ROC:
-	case IIO_EV_TYPE_THRESH_ADAPTIVE:
-	case IIO_EV_TYPE_MAG_ADAPTIVE:
-		break;
-	default:
-		return false;
-	}
-
-	switch (dir) {
-	case IIO_EV_DIR_EITHER:
-	case IIO_EV_DIR_RISING:
-	case IIO_EV_DIR_FALLING:
-		break;
-	default:
-		return false;
-	}
-
-	return true;
-}
-
-static void print_event(struct iio_event_data *event)
-{
-	enum iio_chan_type type = IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event->id);
-	enum iio_modifier mod = IIO_EVENT_CODE_EXTRACT_MODIFIER(event->id);
-	enum iio_event_type ev_type = IIO_EVENT_CODE_EXTRACT_TYPE(event->id);
-	enum iio_event_direction dir = IIO_EVENT_CODE_EXTRACT_DIR(event->id);
-	int chan = IIO_EVENT_CODE_EXTRACT_CHAN(event->id);
-	int chan2 = IIO_EVENT_CODE_EXTRACT_CHAN2(event->id);
-	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);
-		return;
-	}
-
-	printf("Event: time: %lld, ", event->timestamp);
-
-	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 (diff && chan >= 0 && chan2 >= 0)
-		printf("channel: %d-%d, ", chan, chan2);
-	else if (chan >= 0)
-		printf("channel: %d, ", chan);
-
-	printf("evtype: %s, direction: %s\n",
-		iio_ev_type_text[ev_type],
-		iio_ev_dir_text[dir]);
-}
-
-int main(int argc, char **argv)
-{
-	struct iio_event_data event;
-	const char *device_name;
-	char *chrdev_name;
-	int ret;
-	int dev_num;
-	int fd, event_fd;
-
-	if (argc <= 1) {
-		printf("Usage: %s <device_name>\n", argv[0]);
-		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",
-			device_name, dev_num);
-		ret = asprintf(&chrdev_name, "/dev/iio:device%d", dev_num);
-		if (ret < 0) {
-			ret = -ENOMEM;
-			goto error_ret;
-		}
-	} else {
-		/* If we can't find a IIO device by name assume device_name is a
-		   IIO chrdev */
-		chrdev_name = strdup(device_name);
-	}
-
-	fd = open(chrdev_name, 0);
-	if (fd == -1) {
-		fprintf(stdout, "Failed to open %s\n", chrdev_name);
-		ret = -errno;
-		goto error_free_chrdev_name;
-	}
-
-	ret = ioctl(fd, IIO_GET_EVENT_FD_IOCTL, &event_fd);
-
-	close(fd);
-
-	if (ret == -1 || event_fd == -1) {
-		fprintf(stdout, "Failed to retrieve event fd\n");
-		ret = -errno;
-		goto error_free_chrdev_name;
-	}
-
-	while (true) {
-		ret = read(event_fd, &event, sizeof(event));
-		if (ret == -1) {
-			if (errno == EAGAIN) {
-				printf("nothing available\n");
-				continue;
-			} else {
-				perror("Failed to read event from device");
-				ret = -errno;
-				break;
-			}
-		}
-
-		print_event(&event);
-	}
-
-	close(event_fd);
-error_free_chrdev_name:
-	free(chrdev_name);
-error_ret:
-	return ret;
-}
diff --git a/drivers/staging/iio/Documentation/iio_utils.h b/drivers/staging/iio/Documentation/iio_utils.h
deleted file mode 100644
index 6f3a392..0000000
--- a/drivers/staging/iio/Documentation/iio_utils.h
+++ /dev/null
@@ -1,639 +0,0 @@
-/* IIO - useful set of util functionality
- *
- * 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.
- */
-
-/* Made up value to limit allocation sizes */
-#include <string.h>
-#include <stdlib.h>
-#include <ctype.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <dirent.h>
-
-#define IIO_MAX_NAME_LENGTH 30
-
-#define FORMAT_SCAN_ELEMENTS_DIR "%s/scan_elements"
-#define FORMAT_TYPE_FILE "%s_type"
-
-const char *iio_dir = "/sys/bus/iio/devices/";
-
-/**
- * iioutils_break_up_name() - extract generic name from full channel name
- * @full_name: the full channel name
- * @generic_name: the output generic channel name
- **/
-static int iioutils_break_up_name(const char *full_name,
-				  char **generic_name)
-{
-	char *current;
-	char *w, *r;
-	char *working;
-	current = strdup(full_name);
-	working = strtok(current, "_\0");
-	w = working;
-	r = working;
-
-	while (*r != '\0') {
-		if (!isdigit(*r)) {
-			*w = *r;
-			w++;
-		}
-		r++;
-	}
-	*w = '\0';
-	*generic_name = strdup(working);
-	free(current);
-
-	return 0;
-}
-
-/**
- * struct iio_channel_info - information about a given channel
- * @name: channel name
- * @generic_name: general name for channel type
- * @scale: scale factor to be applied for conversion to si units
- * @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
- * @mask: a bit mask for the raw output
- * @is_signed: is the raw value stored signed
- * @enabled: is this channel enabled
- **/
-struct iio_channel_info {
-	char *name;
-	char *generic_name;
-	float scale;
-	float offset;
-	unsigned index;
-	unsigned bytes;
-	unsigned bits_used;
-	unsigned shift;
-	uint64_t mask;
-	unsigned be;
-	unsigned is_signed;
-	unsigned enabled;
-	unsigned location;
-};
-
-/**
- * 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
- * @mask: output a bit mask for the raw data
- * @be: big endian
- * @device_dir: the iio device directory
- * @name: the channel name
- * @generic_name: the channel type name
- **/
-inline 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;
-	DIR *dp;
-	char *scan_el_dir, *builtname, *builtname_generic, *filename = 0;
-	char signchar, endianchar;
-	unsigned padint;
-	const struct dirent *ent;
-
-	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
-	ret = asprintf(&builtname, FORMAT_TYPE_FILE, name);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_free_scan_el_dir;
-	}
-	ret = asprintf(&builtname_generic, FORMAT_TYPE_FILE, generic_name);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_free_builtname;
-	}
-
-	dp = opendir(scan_el_dir);
-	if (dp == NULL) {
-		ret = -errno;
-		goto error_free_builtname_generic;
-	}
-	while (ent = readdir(dp), ent != NULL)
-		/*
-		 * Do we allow devices to override a generic name with
-		 * a specific one?
-		 */
-		if ((strcmp(builtname, ent->d_name) == 0) ||
-		    (strcmp(builtname_generic, ent->d_name) == 0)) {
-			ret = asprintf(&filename,
-				       "%s/%s", scan_el_dir, ent->d_name);
-			if (ret < 0) {
-				ret = -ENOMEM;
-				goto error_closedir;
-			}
-			sysfsfp = fopen(filename, "r");
-			if (sysfsfp == NULL) {
-				printf("failed to open %s\n", filename);
-				ret = -errno;
-				goto error_free_filename;
-			}
-
-			ret = fscanf(sysfsfp,
-				     "%ce:%c%u/%u>>%u",
-				     &endianchar,
-				     &signchar,
-				     bits_used,
-				     &padint, shift);
-			if (ret < 0) {
-				printf("failed to pass scan type description\n");
-				return ret;
-			}
-			*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);
-
-			filename = 0;
-		}
-error_free_filename:
-	if (filename)
-		free(filename);
-error_closedir:
-	closedir(dp);
-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;
-}
-
-inline 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;
-	DIR *dp;
-	char *builtname, *builtname_generic;
-	char *filename = NULL;
-	const struct dirent *ent;
-
-	ret = asprintf(&builtname, "%s_%s", name, param_name);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
-	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) {
-		ret = -errno;
-		goto error_free_builtname_generic;
-	}
-	while (ent = readdir(dp), ent != NULL)
-		if ((strcmp(builtname, ent->d_name) == 0) ||
-		    (strcmp(builtname_generic, ent->d_name) == 0)) {
-			ret = asprintf(&filename,
-				       "%s/%s", device_dir, ent->d_name);
-			if (ret < 0) {
-				ret = -ENOMEM;
-				goto error_closedir;
-			}
-			sysfsfp = fopen(filename, "r");
-			if (!sysfsfp) {
-				ret = -errno;
-				goto error_free_filename;
-			}
-			fscanf(sysfsfp, "%f", output);
-			break;
-		}
-error_free_filename:
-	if (filename)
-		free(filename);
-error_closedir:
-	closedir(dp);
-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
- *
- **/
-
-inline 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;
-			}
-}
-
-/**
- * build_channel_array() - function to figure out what channels are present
- * @device_dir: the IIO device directory in sysfs
- * @
- **/
-inline int build_channel_array(const char *device_dir,
-			      struct iio_channel_info **ci_array,
-			      int *counter)
-{
-	DIR *dp;
-	FILE *sysfsfp;
-	int count, temp, i;
-	struct iio_channel_info *current;
-	int ret;
-	const struct dirent *ent;
-	char *scan_el_dir;
-	char *filename;
-
-	*counter = 0;
-	ret = asprintf(&scan_el_dir, FORMAT_SCAN_ELEMENTS_DIR, device_dir);
-	if (ret < 0) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
-	dp = opendir(scan_el_dir);
-	if (dp == NULL) {
-		ret = -errno;
-		goto error_free_name;
-	}
-	while (ent = readdir(dp), ent != NULL)
-		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
-			   "_en") == 0) {
-			ret = asprintf(&filename,
-				       "%s/%s", scan_el_dir, ent->d_name);
-			if (ret < 0) {
-				ret = -ENOMEM;
-				goto error_close_dir;
-			}
-			sysfsfp = fopen(filename, "r");
-			if (sysfsfp == NULL) {
-				ret = -errno;
-				free(filename);
-				goto error_close_dir;
-			}
-			fscanf(sysfsfp, "%u", &ret);
-			if (ret == 1)
-				(*counter)++;
-			fclose(sysfsfp);
-			free(filename);
-		}
-	*ci_array = malloc(sizeof(**ci_array) * (*counter));
-	if (*ci_array == NULL) {
-		ret = -ENOMEM;
-		goto error_close_dir;
-	}
-	seekdir(dp, 0);
-	count = 0;
-	while (ent = readdir(dp), ent != NULL) {
-		if (strcmp(ent->d_name + strlen(ent->d_name) - strlen("_en"),
-			   "_en") == 0) {
-			current = &(*ci_array)[count++];
-			ret = asprintf(&filename,
-				       "%s/%s", scan_el_dir, ent->d_name);
-			if (ret < 0) {
-				ret = -ENOMEM;
-				/* decrement count to avoid freeing name */
-				count--;
-				goto error_cleanup_array;
-			}
-			sysfsfp = fopen(filename, "r");
-			if (sysfsfp == NULL) {
-				free(filename);
-				ret = -errno;
-				goto error_cleanup_array;
-			}
-			fscanf(sysfsfp, "%u", &current->enabled);
-			fclose(sysfsfp);
-
-			if (!current->enabled) {
-				free(filename);
-				count--;
-				continue;
-			}
-
-			current->scale = 1.0;
-			current->offset = 0;
-			current->name = strndup(ent->d_name,
-						strlen(ent->d_name) -
-						strlen("_en"));
-			if (current->name == NULL) {
-				free(filename);
-				ret = -ENOMEM;
-				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);
-				goto error_cleanup_array;
-			}
-			ret = asprintf(&filename,
-				       "%s/%s_index",
-				       scan_el_dir,
-				       current->name);
-			if (ret < 0) {
-				free(filename);
-				ret = -ENOMEM;
-				goto error_cleanup_array;
-			}
-			sysfsfp = fopen(filename, "r");
-			fscanf(sysfsfp, "%u", &current->index);
-			fclose(sysfsfp);
-			free(filename);
-			/* Find the scale */
-			ret = iioutils_get_param_float(&current->scale,
-						       "scale",
-						       device_dir,
-						       current->name,
-						       current->generic_name);
-			if (ret < 0)
-				goto error_cleanup_array;
-			ret = iioutils_get_param_float(&current->offset,
-						       "offset",
-						       device_dir,
-						       current->name,
-						       current->generic_name);
-			if (ret < 0)
-				goto error_cleanup_array;
-			ret = iioutils_get_type(&current->is_signed,
-						&current->bytes,
-						&current->bits_used,
-						&current->shift,
-						&current->mask,
-						&current->be,
-						device_dir,
-						current->name,
-						current->generic_name);
-		}
-	}
-
-	closedir(dp);
-	/* reorder so that the array is in index order */
-	bsort_channel_array_by_index(ci_array, *counter);
-
-	return 0;
-
-error_cleanup_array:
-	for (i = count - 1;  i >= 0; i--)
-		free((*ci_array)[i].name);
-	free(*ci_array);
-error_close_dir:
-	closedir(dp);
-error_free_name:
-	free(scan_el_dir);
-error_ret:
-	return ret;
-}
-
-/**
- * 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
- *
- * Typical types this is used for are device and trigger.
- **/
-inline int find_type_by_name(const char *name, const char *type)
-{
-	const struct dirent *ent;
-	int number, numstrlen;
-
-	FILE *nameFile;
-	DIR *dp;
-	char thisname[IIO_MAX_NAME_LENGTH];
-	char *filename;
-
-	dp = opendir(iio_dir);
-	if (dp == NULL) {
-		printf("No industrialio devices available");
-		return -ENODEV;
-	}
-
-	while (ent = readdir(dp), ent != NULL) {
-		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);
-			/* 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)
-					return -ENOMEM;
-				sprintf(filename, "%s%s%d/name",
-					iio_dir,
-					type,
-					number);
-				nameFile = fopen(filename, "r");
-				if (!nameFile)
-					continue;
-				free(filename);
-				fscanf(nameFile, "%s", thisname);
-				if (strcmp(name, thisname) == 0)
-					return number;
-				fclose(nameFile);
-			}
-		}
-	}
-	return -ENODEV;
-}
-
-inline int _write_sysfs_int(char *filename, char *basedir, int val, int verify)
-{
-	int ret;
-	FILE *sysfsfp;
-	int test;
-	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
-	if (temp == NULL)
-		return -ENOMEM;
-	sprintf(temp, "%s/%s", basedir, filename);
-	sysfsfp = fopen(temp, "w");
-	if (sysfsfp == NULL) {
-		printf("failed to open %s\n", temp);
-		ret = -errno;
-		goto error_free;
-	}
-	fprintf(sysfsfp, "%d", val);
-	fclose(sysfsfp);
-	if (verify) {
-		sysfsfp = fopen(temp, "r");
-		if (sysfsfp == NULL) {
-			printf("failed to open %s\n", temp);
-			ret = -errno;
-			goto error_free;
-		}
-		fscanf(sysfsfp, "%d", &test);
-		if (test != val) {
-			printf("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)
-{
-	return _write_sysfs_int(filename, basedir, val, 0);
-}
-
-int write_sysfs_int_and_verify(char *filename, char *basedir, int val)
-{
-	return _write_sysfs_int(filename, basedir, val, 1);
-}
-
-int _write_sysfs_string(char *filename, char *basedir, 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");
-		return -ENOMEM;
-	}
-	sprintf(temp, "%s/%s", basedir, filename);
-	sysfsfp = fopen(temp, "w");
-	if (sysfsfp == NULL) {
-		printf("Could not open %s\n", temp);
-		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");
-			ret = -errno;
-			goto error_free;
-		}
-		fscanf(sysfsfp, "%s", temp);
-		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);
-			ret = -1;
-		}
-	}
-error_free:
-	free(temp);
-
-	return ret;
-}
-
-/**
- * write_sysfs_string_and_verify() - string write, readback and verify
- * @filename: name of file to write to
- * @basedir: the sysfs directory in which the file is to be found
- * @val: the string to write
- **/
-int write_sysfs_string_and_verify(char *filename, char *basedir, char *val)
-{
-	return _write_sysfs_string(filename, basedir, val, 1);
-}
-
-int write_sysfs_string(char *filename, char *basedir, char *val)
-{
-	return _write_sysfs_string(filename, basedir, val, 0);
-}
-
-int read_sysfs_posint(char *filename, char *basedir)
-{
-	int ret;
-	FILE  *sysfsfp;
-	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
-	if (temp == NULL) {
-		printf("Memory allocation failed");
-		return -ENOMEM;
-	}
-	sprintf(temp, "%s/%s", basedir, filename);
-	sysfsfp = fopen(temp, "r");
-	if (sysfsfp == NULL) {
-		ret = -errno;
-		goto error_free;
-	}
-	fscanf(sysfsfp, "%d\n", &ret);
-	fclose(sysfsfp);
-error_free:
-	free(temp);
-	return ret;
-}
-
-int read_sysfs_float(char *filename, char *basedir, float *val)
-{
-	float ret = 0;
-	FILE  *sysfsfp;
-	char *temp = malloc(strlen(basedir) + strlen(filename) + 2);
-	if (temp == NULL) {
-		printf("Memory allocation failed");
-		return -ENOMEM;
-	}
-	sprintf(temp, "%s/%s", basedir, filename);
-	sysfsfp = fopen(temp, "r");
-	if (sysfsfp == NULL) {
-		ret = -errno;
-		goto error_free;
-	}
-	fscanf(sysfsfp, "%f\n", val);
-	fclose(sysfsfp);
-error_free:
-	free(temp);
-	return ret;
-}
diff --git a/drivers/staging/iio/Documentation/inkernel.txt b/drivers/staging/iio/Documentation/inkernel.txt
deleted file mode 100644
index a05823e..0000000
--- a/drivers/staging/iio/Documentation/inkernel.txt
+++ /dev/null
@@ -1,58 +0,0 @@
-Industrial I/O Subsystem in kernel consumers.
-
-The IIO subsystem can act as a layer under other elements of the kernel
-providing a means of obtaining ADC type readings or of driving DAC type
-signals.  The functionality supported will grow as use cases arise.
-
-Describing the channel mapping (iio/machine.h)
-
-Channel associations are described using:
-
-struct iio_map {
-	const char *adc_channel_label;
-	const char *consumer_dev_name;
-	const char *consumer_channel;
-};
-
-adc_channel_label identifies the channel on the IIO device by being
-matched against the datasheet_name field of the iio_chan_spec.
-
-consumer_dev_name allows identification of the consumer device.
-This are then used to find the channel mapping from the consumer device (see
-below).
-
-Finally consumer_channel is a string identifying the channel to the consumer.
-(Perhaps 'battery_voltage' or similar).
-
-An array of these structures is then passed to the IIO driver.
-
-Supporting in kernel interfaces in the driver (driver.h)
-
-The driver must provide datasheet_name values for its channels and
-must pass the iio_map structures and a pointer to its own iio_dev structure
- on to the core via a call to iio_map_array_register.  On removal,
-iio_map_array_unregister reverses this process.
-
-The result of this is that the IIO core now has all the information needed
-to associate a given channel with the consumer requesting it.
-
-Acting as an IIO consumer (consumer.h)
-
-The consumer first has to obtain an iio_channel structure from the core
-by calling iio_channel_get().  The correct channel is identified by:
-
-* matching dev or dev_name against consumer_dev and consumer_dev_name
-* matching consumer_channel against consumer_channel in the map
-
-There are then a number of functions that can be used to get information
-about this channel such as it's current reading.
-
-e.g.
-iio_st_read_channel_raw() - get a reading
-iio_st_read_channel_type() - get the type of channel
-
-There is also provision for retrieving all of the channels associated
-with a given consumer.  This is useful for generic drivers such as
-iio_hwmon where the number and naming of channels is not known by the
-consumer driver.  To do this, use iio_st_channel_get_all.
-
diff --git a/drivers/staging/iio/Documentation/overview.txt b/drivers/staging/iio/Documentation/overview.txt
deleted file mode 100644
index afc39ec..0000000
--- a/drivers/staging/iio/Documentation/overview.txt
+++ /dev/null
@@ -1,57 +0,0 @@
-Overview of IIO
-
-The Industrial I/O subsystem is intended to provide support for devices
-that in some sense are analog to digital converters (ADCs). As many
-actual devices combine some ADCs with digital to analog converters
-(DACs) that functionality is also supported.
-
-The aim is to fill the gap between the somewhat similar hwmon and
-input subsystems.  Hwmon is very much directed at low sample rate
-sensors used in applications such as fan speed control and temperature
-measurement.  Input is, as it's name suggests focused on input
-devices. In some cases there is considerable overlap between these and
-IIO.
-
-A typical device falling into this category would be connected via SPI
-or I2C.
-
-Functionality of IIO
-
-* Basic device registration and handling. This is very similar to
-hwmon with simple polled access to device channels via sysfs.
-
-* Event chrdevs.  These are similar to input in that they provide a
-route to user space for hardware triggered events. Such events include
-threshold detectors, free-fall detectors and more complex action
-detection.  The events themselves are currently very simple with
-merely an event code and a timestamp.  Any data associated with the
-event must be accessed via polling.
-
-Note: A given device may have one or more event channel.  These events are
-turned on or off (if possible) via sysfs interfaces.
-
-* Hardware buffer support.  Some recent sensors have included
-fifo / ring buffers on the sensor chip.  These greatly reduce the load
-on the host CPU by buffering relatively large numbers of data samples
-based on an internal sampling clock. Examples include VTI SCA3000
-series and Analog Device ADXL345 accelerometers.  Each buffer supports
-polling to establish when data is available.
-
-* Trigger and software buffer support. In many data analysis
-applications it it useful to be able to capture data based on some
-external signal (trigger).  These triggers might be a data ready
-signal, a gpio line connected to some external system or an on
-processor periodic interrupt.  A single trigger may initialize data
-capture or reading from a number of sensors.  These triggers are
-used in IIO to fill software buffers acting in a very similar
-fashion to the hardware buffers described above.
-
-Other documentation:
-
-device.txt - elements of a typical device driver.
-
-trigger.txt - elements of a typical trigger driver.
-
-ring.txt - additional elements required for buffer support.
-
-sysfs-bus-iio - abi documentation file.
diff --git a/drivers/staging/iio/Documentation/ring.txt b/drivers/staging/iio/Documentation/ring.txt
deleted file mode 100644
index e338077..0000000
--- a/drivers/staging/iio/Documentation/ring.txt
+++ /dev/null
@@ -1,47 +0,0 @@
-Buffer support within IIO
-
-This document is intended as a general overview of the functionality
-a buffer may supply and how it is specified within IIO.  For more
-specific information on a given buffer implementation, see the
-comments in the source code.  Note that some drivers allow buffer
-implementation to be selected at compile time via Kconfig options.
-
-A given buffer implementation typically embeds a struct
-iio_ring_buffer and it is a pointer to this that is provided to the
-IIO core. Access to the embedding structure is typically done via
-container_of functions.
-
-struct iio_ring_buffer contains a struct iio_ring_setup_ops *setup_ops
-which in turn contains the 4 function pointers
-(preenable, postenable, predisable and postdisable).
-These are used to perform device specific steps on either side
-of the core changing it's current mode to indicate that the buffer
-is enabled or disabled (along with enabling triggering etc as appropriate).
-
-Also in struct iio_ring_buffer is a struct iio_ring_access_funcs.
-The function pointers within here are used to allow the core to handle
-as much buffer functionality as possible. Note almost all of these
-are optional.
-
-store_to
-  If possible, push data to the buffer.
-
-read_last
-  If possible, get the most recent scan from the buffer (without removal).
-  This provides polling like functionality whilst the ring buffering is in
-  use without a separate read from the device.
-
-rip_first_n
-  The primary buffer reading function. Note that it may well not return
-  as much data as requested.
-
-request_update
-  If parameters have changed that require reinitialization or configuration of
-  the buffer this will trigger it.
-
-get_bytes_per_datum, set_bytes_per_datum
-  Get/set the number of bytes for a complete scan. (All samples + timestamp)
-
-get_length / set_length
-  Get/set the number of complete scans that may be held by the buffer.
-
-- 
1.7.3.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists