[linux-2.6-block.git] / drivers / iio / industrialio-event.c

/* Industrial I/O event handling
 *
 * 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.
 *
 * Based on elements of hwmon and input subsystems.
 */

#include <linux/anon_inodes.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/kfifo.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/wait.h>
#include <linux/iio/iio.h>
#include "iio_core.h"
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>

/**
 * struct iio_event_interface - chrdev interface for an event line
 * @wait:		wait queue to allow blocking reads of events
 * @det_events:		list of detected events
 * @dev_attr_list:	list of event interface sysfs attribute
 * @flags:		file operations related flags including busy flag.
 * @group:		event interface sysfs attribute group
 * @read_lock:		lock to protect kfifo read operations
 */
struct iio_event_interface {
	wait_queue_head_t	wait;
	DECLARE_KFIFO(det_events, struct iio_event_data, 16);

	struct list_head	dev_attr_list;
	unsigned long		flags;
	struct attribute_group	group;
	struct mutex		read_lock;
};

/**
 * iio_push_event() - try to add event to the list for userspace reading
 * @indio_dev:		IIO device structure
 * @ev_code:		What event
 * @timestamp:		When the event occurred
 *
 * Note: The caller must make sure that this function is not running
 * concurrently for the same indio_dev more than once.
 **/
int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp)
{
	struct iio_event_interface *ev_int = indio_dev->event_interface;
	struct iio_event_data ev;
	int copied;

	/* Does anyone care? */
	if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {

		ev.id = ev_code;
		ev.timestamp = timestamp;

		copied = kfifo_put(&ev_int->det_events, ev);
		if (copied != 0)
			wake_up_poll(&ev_int->wait, POLLIN);
	}

	return 0;
}
EXPORT_SYMBOL(iio_push_event);

/**
 * iio_event_poll() - poll the event queue to find out if it has data
 * @filep:	File structure pointer to identify the device
 * @wait:	Poll table pointer to add the wait queue on
 *
 * Return: (POLLIN | POLLRDNORM) if data is available for reading
 *	   or a negative error code on failure
 */
static unsigned int iio_event_poll(struct file *filep,
			     struct poll_table_struct *wait)
{
	struct iio_dev *indio_dev = filep->private_data;
	struct iio_event_interface *ev_int = indio_dev->event_interface;
	unsigned int events = 0;

	if (!indio_dev->info)
		return events;

	poll_wait(filep, &ev_int->wait, wait);

	if (!kfifo_is_empty(&ev_int->det_events))
		events = POLLIN | POLLRDNORM;

	return events;
}

static ssize_t iio_event_chrdev_read(struct file *filep,
				     char __user *buf,
				     size_t count,
				     loff_t *f_ps)
{
	struct iio_dev *indio_dev = filep->private_data;
	struct iio_event_interface *ev_int = indio_dev->event_interface;
	unsigned int copied;
	int ret;

	if (!indio_dev->info)
		return -ENODEV;

	if (count < sizeof(struct iio_event_data))
		return -EINVAL;

	do {
		if (kfifo_is_empty(&ev_int->det_events)) {
			if (filep->f_flags & O_NONBLOCK)
				return -EAGAIN;

			ret = wait_event_interruptible(ev_int->wait,
					!kfifo_is_empty(&ev_int->det_events) ||
					indio_dev->info == NULL);
			if (ret)
				return ret;
			if (indio_dev->info == NULL)
				return -ENODEV;
		}

		if (mutex_lock_interruptible(&ev_int->read_lock))
			return -ERESTARTSYS;
		ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);
		mutex_unlock(&ev_int->read_lock);

		if (ret)
			return ret;

		/*
		 * If we couldn't read anything from the fifo (a different
		 * thread might have been faster) we either return -EAGAIN if
		 * the file descriptor is non-blocking, otherwise we go back to
		 * sleep and wait for more data to arrive.
		 */
		if (copied == 0 && (filep->f_flags & O_NONBLOCK))
			return -EAGAIN;

	} while (copied == 0);

	return copied;
}

static int iio_event_chrdev_release(struct inode *inode, struct file *filep)
{
	struct iio_dev *indio_dev = filep->private_data;
	struct iio_event_interface *ev_int = indio_dev->event_interface;

	clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);

	iio_device_put(indio_dev);

	return 0;
}

static const struct file_operations iio_event_chrdev_fileops = {
	.read =  iio_event_chrdev_read,
	.poll =  iio_event_poll,
	.release = iio_event_chrdev_release,
	.owner = THIS_MODULE,
	.llseek = noop_llseek,
};

int iio_event_getfd(struct iio_dev *indio_dev)
{
	struct iio_event_interface *ev_int = indio_dev->event_interface;
	int fd;

	if (ev_int == NULL)
		return -ENODEV;

	if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags))
		return -EBUSY;

	iio_device_get(indio_dev);

	fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
				indio_dev, O_RDONLY | O_CLOEXEC);
	if (fd < 0) {
		clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
		iio_device_put(indio_dev);
	} else {
		kfifo_reset_out(&ev_int->det_events);
	}

	return fd;
}

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",
	[IIO_EV_TYPE_CHANGE] = "change",
};

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_ev_info_text[] = {
	[IIO_EV_INFO_ENABLE] = "en",
	[IIO_EV_INFO_VALUE] = "value",
	[IIO_EV_INFO_HYSTERESIS] = "hysteresis",
	[IIO_EV_INFO_PERIOD] = "period",
	[IIO_EV_INFO_HIGH_PASS_FILTER_3DB] = "high_pass_filter_3db",
	[IIO_EV_INFO_LOW_PASS_FILTER_3DB] = "low_pass_filter_3db",
};

static enum iio_event_direction iio_ev_attr_dir(struct iio_dev_attr *attr)
{
	return attr->c->event_spec[attr->address & 0xffff].dir;
}

static enum iio_event_type iio_ev_attr_type(struct iio_dev_attr *attr)
{
	return attr->c->event_spec[attr->address & 0xffff].type;
}

static enum iio_event_info iio_ev_attr_info(struct iio_dev_attr *attr)
{
	return (attr->address >> 16) & 0xffff;
}

static ssize_t iio_ev_state_store(struct device *dev,
				  struct device_attribute *attr,
				  const char *buf,
				  size_t len)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	int ret;
	bool val;

	ret = strtobool(buf, &val);
	if (ret < 0)
		return ret;

	ret = indio_dev->info->write_event_config(indio_dev,
		this_attr->c, iio_ev_attr_type(this_attr),
		iio_ev_attr_dir(this_attr), val);

	return (ret < 0) ? ret : len;
}

static ssize_t iio_ev_state_show(struct device *dev,
				 struct device_attribute *attr,
				 char *buf)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	int val;

	val = indio_dev->info->read_event_config(indio_dev,
		this_attr->c, iio_ev_attr_type(this_attr),
		iio_ev_attr_dir(this_attr));
	if (val < 0)
		return val;
	else
		return sprintf(buf, "%d\n", val);
}

static ssize_t iio_ev_value_show(struct device *dev,
				 struct device_attribute *attr,
				 char *buf)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	int val, val2, val_arr[2];
	int ret;

	ret = indio_dev->info->read_event_value(indio_dev,
		this_attr->c, iio_ev_attr_type(this_attr),
		iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
		&val, &val2);
	if (ret < 0)
		return ret;
	val_arr[0] = val;
	val_arr[1] = val2;
	return iio_format_value(buf, ret, 2, val_arr);
}

static ssize_t iio_ev_value_store(struct device *dev,
				  struct device_attribute *attr,
				  const char *buf,
				  size_t len)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	int val, val2;
	int ret;

	if (!indio_dev->info->write_event_value)
		return -EINVAL;

	ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
	if (ret)
		return ret;
	ret = indio_dev->info->write_event_value(indio_dev,
		this_attr->c, iio_ev_attr_type(this_attr),
		iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
		val, val2);
	if (ret < 0)
		return ret;

	return len;
}

static int iio_device_add_event(struct iio_dev *indio_dev,
	const struct iio_chan_spec *chan, unsigned int spec_index,
	enum iio_event_type type, enum iio_event_direction dir,
	enum iio_shared_by shared_by, const unsigned long *mask)
{
	ssize_t (*show)(struct device *, struct device_attribute *, char *);
	ssize_t (*store)(struct device *, struct device_attribute *,
		const char *, size_t);
	unsigned int attrcount = 0;
	unsigned int i;
	char *postfix;
	int ret;

	for_each_set_bit(i, mask, sizeof(*mask)*8) {
		if (i >= ARRAY_SIZE(iio_ev_info_text))
			return -EINVAL;
		if (dir != IIO_EV_DIR_NONE)
			postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
					iio_ev_type_text[type],
					iio_ev_dir_text[dir],
					iio_ev_info_text[i]);
		else
			postfix = kasprintf(GFP_KERNEL, "%s_%s",
					iio_ev_type_text[type],
					iio_ev_info_text[i]);
		if (postfix == NULL)
			return -ENOMEM;

		if (i == IIO_EV_INFO_ENABLE) {
			show = iio_ev_state_show;
			store = iio_ev_state_store;
		} else {
			show = iio_ev_value_show;
			store = iio_ev_value_store;
		}

		ret = __iio_add_chan_devattr(postfix, chan, show, store,
			 (i << 16) | spec_index, shared_by, &indio_dev->dev,
			&indio_dev->event_interface->dev_attr_list);
		kfree(postfix);

		if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
			continue;

		if (ret)
			return ret;

		attrcount++;
	}

	return attrcount;
}

static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan)
{
	int ret = 0, i, attrcount = 0;
	enum iio_event_direction dir;
	enum iio_event_type type;

	for (i = 0; i < chan->num_event_specs; i++) {
		type = chan->event_spec[i].type;
		dir = chan->event_spec[i].dir;

		ret = iio_device_add_event(indio_dev, chan, i, type, dir,
			IIO_SEPARATE, &chan->event_spec[i].mask_separate);
		if (ret < 0)
			return ret;
		attrcount += ret;

		ret = iio_device_add_event(indio_dev, chan, i, type, dir,
			IIO_SHARED_BY_TYPE,
			&chan->event_spec[i].mask_shared_by_type);
		if (ret < 0)
			return ret;
		attrcount += ret;

		ret = iio_device_add_event(indio_dev, chan, i, type, dir,
			IIO_SHARED_BY_DIR,
			&chan->event_spec[i].mask_shared_by_dir);
		if (ret < 0)
			return ret;
		attrcount += ret;

		ret = iio_device_add_event(indio_dev, chan, i, type, dir,
			IIO_SHARED_BY_ALL,
			&chan->event_spec[i].mask_shared_by_all);
		if (ret < 0)
			return ret;
		attrcount += ret;
	}
	ret = attrcount;
	return ret;
}

static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
{
	int j, ret, attrcount = 0;

	/* Dynamically created from the channels array */
	for (j = 0; j < indio_dev->num_channels; j++) {
		ret = iio_device_add_event_sysfs(indio_dev,
						 &indio_dev->channels[j]);
		if (ret < 0)
			return ret;
		attrcount += ret;
	}
	return attrcount;
}

static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
{
	int j;

	for (j = 0; j < indio_dev->num_channels; j++) {
		if (indio_dev->channels[j].num_event_specs != 0)
			return true;
	}
	return false;
}

static void iio_setup_ev_int(struct iio_event_interface *ev_int)
{
	INIT_KFIFO(ev_int->det_events);
	init_waitqueue_head(&ev_int->wait);
	mutex_init(&ev_int->read_lock);
}

static const char *iio_event_group_name = "events";
int iio_device_register_eventset(struct iio_dev *indio_dev)
{
	struct iio_dev_attr *p;
	int ret = 0, attrcount_orig = 0, attrcount, attrn;
	struct attribute **attr;

	if (!(indio_dev->info->event_attrs ||
	      iio_check_for_dynamic_events(indio_dev)))
		return 0;

	indio_dev->event_interface =
		kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
	if (indio_dev->event_interface == NULL)
		return -ENOMEM;

	INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);

	iio_setup_ev_int(indio_dev->event_interface);
	if (indio_dev->info->event_attrs != NULL) {
		attr = indio_dev->info->event_attrs->attrs;
		while (*attr++ != NULL)
			attrcount_orig++;
	}
	attrcount = attrcount_orig;
	if (indio_dev->channels) {
		ret = __iio_add_event_config_attrs(indio_dev);
		if (ret < 0)
			goto error_free_setup_event_lines;
		attrcount += ret;
	}

	indio_dev->event_interface->group.name = iio_event_group_name;
	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
							  sizeof(indio_dev->event_interface->group.attrs[0]),
							  GFP_KERNEL);
	if (indio_dev->event_interface->group.attrs == NULL) {
		ret = -ENOMEM;
		goto error_free_setup_event_lines;
	}
	if (indio_dev->info->event_attrs)
		memcpy(indio_dev->event_interface->group.attrs,
		       indio_dev->info->event_attrs->attrs,
		       sizeof(indio_dev->event_interface->group.attrs[0])
		       *attrcount_orig);
	attrn = attrcount_orig;
	/* Add all elements from the list. */
	list_for_each_entry(p,
			    &indio_dev->event_interface->dev_attr_list,
			    l)
		indio_dev->event_interface->group.attrs[attrn++] =
			&p->dev_attr.attr;
	indio_dev->groups[indio_dev->groupcounter++] =
		&indio_dev->event_interface->group;

	return 0;

error_free_setup_event_lines:
	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
	kfree(indio_dev->event_interface);
	indio_dev->event_interface = NULL;
	return ret;
}

/**
 * iio_device_wakeup_eventset - Wakes up the event waitqueue
 * @indio_dev: The IIO device
 *
 * Wakes up the event waitqueue used for poll() and blocking read().
 * Should usually be called when the device is unregistered.
 */
void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
{
	if (indio_dev->event_interface == NULL)
		return;
	wake_up(&indio_dev->event_interface->wait);
}

void iio_device_unregister_eventset(struct iio_dev *indio_dev)
{
	if (indio_dev->event_interface == NULL)
		return;
	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
	kfree(indio_dev->event_interface->group.attrs);
	kfree(indio_dev->event_interface);
}
Commit	Line	Data
0a769a95 LPC	1	/* Industrial I/O event handling
	2	*
	3	* Copyright (c) 2008 Jonathan Cameron
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License version 2 as published by
	7	* the Free Software Foundation.
	8	*
	9	* Based on elements of hwmon and input subsystems.
	10	*/
	11
	12	#include <linux/anon_inodes.h>
	13	#include <linux/device.h>
	14	#include <linux/fs.h>
	15	#include <linux/kernel.h>
2c00193f	16	#include <linux/kfifo.h>
0a769a95	17	#include <linux/module.h>
e18045ed	18	#include <linux/poll.h>
0a769a95 LPC	19	#include <linux/sched.h>
	20	#include <linux/slab.h>
	21	#include <linux/uaccess.h>
	22	#include <linux/wait.h>
06458e27	23	#include <linux/iio/iio.h>
0a769a95	24	#include "iio_core.h"
06458e27 JC	25	#include <linux/iio/sysfs.h>
06458e27 JC	26	#include <linux/iio/events.h>
0a769a95	27
0a769a95 LPC	28	/**
	29	* struct iio_event_interface - chrdev interface for an event line
	30	* @wait: wait queue to allow blocking reads of events
0a769a95	31	* @det_events: list of detected events
0a769a95 LPC	32	* @dev_attr_list: list of event interface sysfs attribute
	33	* @flags: file operations related flags including busy flag.
	34	* @group: event interface sysfs attribute group
a316c01d	35	* @read_lock: lock to protect kfifo read operations
0a769a95 LPC	36	*/
	37	struct iio_event_interface {
	38	wait_queue_head_t wait;
2c00193f LPC	39	DECLARE_KFIFO(det_events, struct iio_event_data, 16);
2c00193f LPC	40
0a769a95 LPC	41	struct list_head dev_attr_list;
	42	unsigned long flags;
	43	struct attribute_group group;
b91accaf	44	struct mutex read_lock;
0a769a95 LPC	45	};
0a769a95 LPC	46
a7e57dce SK	47	/**
	48	* iio_push_event() - try to add event to the list for userspace reading
	49	* @indio_dev: IIO device structure
	50	* @ev_code: What event
	51	* @timestamp: When the event occurred
b91accaf LPC	52	*
	53	* Note: The caller must make sure that this function is not running
	54	* concurrently for the same indio_dev more than once.
a7e57dce	55	**/
0a769a95 LPC	56	int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp)
	57	{
	58	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f LPC	59	struct iio_event_data ev;
2c00193f LPC	60	int copied;
0a769a95 LPC	61
0a769a95 LPC	62	/* Does anyone care? */
0a769a95	63	if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
0a769a95	64
2c00193f LPC	65	ev.id = ev_code;
	66	ev.timestamp = timestamp;
	67
498d319b	68	copied = kfifo_put(&ev_int->det_events, ev);
2c00193f	69	if (copied != 0)
b91accaf	70	wake_up_poll(&ev_int->wait, POLLIN);
43ba1100	71	}
0a769a95	72
2c00193f	73	return 0;
0a769a95 LPC	74	}
	75	EXPORT_SYMBOL(iio_push_event);
	76
e18045ed LPC	77	/**
e18045ed LPC	78	* iio_event_poll() - poll the event queue to find out if it has data
a316c01d CO	79	* @filep: File structure pointer to identify the device
	80	* @wait: Poll table pointer to add the wait queue on
	81	*
	82	* Return: (POLLIN \| POLLRDNORM) if data is available for reading
	83	* or a negative error code on failure
e18045ed LPC	84	*/
	85	static unsigned int iio_event_poll(struct file *filep,
	86	struct poll_table_struct *wait)
	87	{
cadc2125 LPC	88	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	89	struct iio_event_interface *ev_int = indio_dev->event_interface;
e18045ed LPC	90	unsigned int events = 0;
e18045ed LPC	91
f18e7a06	92	if (!indio_dev->info)
41d903c0	93	return events;
f18e7a06	94
e18045ed LPC	95	poll_wait(filep, &ev_int->wait, wait);
e18045ed LPC	96
e18045ed LPC	97	if (!kfifo_is_empty(&ev_int->det_events))
e18045ed LPC	98	events = POLLIN \| POLLRDNORM;
e18045ed LPC	99
	100	return events;
	101	}
	102
0a769a95 LPC	103	static ssize_t iio_event_chrdev_read(struct file *filep,
	104	char __user *buf,
	105	size_t count,
	106	loff_t *f_ps)
	107	{
cadc2125 LPC	108	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	109	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f	110	unsigned int copied;
0a769a95 LPC	111	int ret;
0a769a95 LPC	112
f18e7a06 LPC	113	if (!indio_dev->info)
	114	return -ENODEV;
	115
2c00193f	116	if (count < sizeof(struct iio_event_data))
0a769a95 LPC	117	return -EINVAL;
0a769a95 LPC	118
b91accaf LPC	119	do {
	120	if (kfifo_is_empty(&ev_int->det_events)) {
	121	if (filep->f_flags & O_NONBLOCK)
	122	return -EAGAIN;
	123
	124	ret = wait_event_interruptible(ev_int->wait,
d2f0a48f LPC	125	!kfifo_is_empty(&ev_int->det_events) \|\|
d2f0a48f LPC	126	indio_dev->info == NULL);
b91accaf LPC	127	if (ret)
	128	return ret;
	129	if (indio_dev->info == NULL)
	130	return -ENODEV;
d2f0a48f	131	}
0a769a95	132
b91accaf LPC	133	if (mutex_lock_interruptible(&ev_int->read_lock))
	134	return -ERESTARTSYS;
	135	ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);
	136	mutex_unlock(&ev_int->read_lock);
	137
	138	if (ret)
	139	return ret;
	140
	141	/*
	142	* If we couldn't read anything from the fifo (a different
	143	* thread might have been faster) we either return -EAGAIN if
	144	* the file descriptor is non-blocking, otherwise we go back to
	145	* sleep and wait for more data to arrive.
	146	*/
	147	if (copied == 0 && (filep->f_flags & O_NONBLOCK))
	148	return -EAGAIN;
0a769a95	149
b91accaf	150	} while (copied == 0);
43ba1100	151
b91accaf	152	return copied;
0a769a95 LPC	153	}
	154
	155	static int iio_event_chrdev_release(struct inode inode, struct file filep)
	156	{
cadc2125 LPC	157	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	158	struct iio_event_interface *ev_int = indio_dev->event_interface;
0a769a95	159
b91accaf	160	clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
0a769a95	161
cadc2125 LPC	162	iio_device_put(indio_dev);
cadc2125 LPC	163
0a769a95 LPC	164	return 0;
	165	}
	166
	167	static const struct file_operations iio_event_chrdev_fileops = {
	168	.read = iio_event_chrdev_read,
e18045ed	169	.poll = iio_event_poll,
0a769a95 LPC	170	.release = iio_event_chrdev_release,
	171	.owner = THIS_MODULE,
	172	.llseek = noop_llseek,
	173	};
	174
	175	int iio_event_getfd(struct iio_dev *indio_dev)
	176	{
	177	struct iio_event_interface *ev_int = indio_dev->event_interface;
	178	int fd;
	179
	180	if (ev_int == NULL)
	181	return -ENODEV;
	182
b91accaf	183	if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags))
0a769a95	184	return -EBUSY;
b91accaf	185
cadc2125 LPC	186	iio_device_get(indio_dev);
	187
	188	fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
e2aad1d5	189	indio_dev, O_RDONLY \| O_CLOEXEC);
0a769a95	190	if (fd < 0) {
b91accaf	191	clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
cadc2125	192	iio_device_put(indio_dev);
b91accaf LPC	193	} else {
b91accaf LPC	194	kfifo_reset_out(&ev_int->det_events);
0a769a95	195	}
b91accaf	196
0a769a95 LPC	197	return fd;
	198	}
	199
	200	static const char * const iio_ev_type_text[] = {
	201	[IIO_EV_TYPE_THRESH] = "thresh",
	202	[IIO_EV_TYPE_MAG] = "mag",
	203	[IIO_EV_TYPE_ROC] = "roc",
	204	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
	205	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
27be8423	206	[IIO_EV_TYPE_CHANGE] = "change",
0a769a95 LPC	207	};
	208
	209	static const char * const iio_ev_dir_text[] = {
	210	[IIO_EV_DIR_EITHER] = "either",
	211	[IIO_EV_DIR_RISING] = "rising",
	212	[IIO_EV_DIR_FALLING] = "falling"
	213	};
	214
b4e3ac0a LPC	215	static const char * const iio_ev_info_text[] = {
	216	[IIO_EV_INFO_ENABLE] = "en",
	217	[IIO_EV_INFO_VALUE] = "value",
ec6670ae	218	[IIO_EV_INFO_HYSTERESIS] = "hysteresis",
77a533c7	219	[IIO_EV_INFO_PERIOD] = "period",
3f7f642b MF	220	[IIO_EV_INFO_HIGH_PASS_FILTER_3DB] = "high_pass_filter_3db",
3f7f642b MF	221	[IIO_EV_INFO_LOW_PASS_FILTER_3DB] = "low_pass_filter_3db",
b4e3ac0a LPC	222	};
	223
	224	static enum iio_event_direction iio_ev_attr_dir(struct iio_dev_attr *attr)
	225	{
	226	return attr->c->event_spec[attr->address & 0xffff].dir;
	227	}
	228
	229	static enum iio_event_type iio_ev_attr_type(struct iio_dev_attr *attr)
	230	{
	231	return attr->c->event_spec[attr->address & 0xffff].type;
	232	}
	233
	234	static enum iio_event_info iio_ev_attr_info(struct iio_dev_attr *attr)
	235	{
	236	return (attr->address >> 16) & 0xffff;
	237	}
	238
0a769a95 LPC	239	static ssize_t iio_ev_state_store(struct device *dev,
	240	struct device_attribute *attr,
	241	const char *buf,
	242	size_t len)
	243	{
e53f5ac5	244	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	245	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	246	int ret;
	247	bool val;
	248
	249	ret = strtobool(buf, &val);
	250	if (ret < 0)
	251	return ret;
	252
cb955852 LPC	253	ret = indio_dev->info->write_event_config(indio_dev,
	254	this_attr->c, iio_ev_attr_type(this_attr),
	255	iio_ev_attr_dir(this_attr), val);
b4e3ac0a	256
0a769a95 LPC	257	return (ret < 0) ? ret : len;
	258	}
	259
	260	static ssize_t iio_ev_state_show(struct device *dev,
	261	struct device_attribute *attr,
	262	char *buf)
	263	{
e53f5ac5	264	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	265	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	266	int val;
0a769a95	267
cb955852 LPC	268	val = indio_dev->info->read_event_config(indio_dev,
	269	this_attr->c, iio_ev_attr_type(this_attr),
	270	iio_ev_attr_dir(this_attr));
0a769a95 LPC	271	if (val < 0)
	272	return val;
	273	else
	274	return sprintf(buf, "%d\n", val);
	275	}
	276
	277	static ssize_t iio_ev_value_show(struct device *dev,
	278	struct device_attribute *attr,
	279	char *buf)
	280	{
e53f5ac5	281	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	282	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
9fbfb4b3	283	int val, val2, val_arr[2];
b4e3ac0a	284	int ret;
0a769a95	285
cb955852 LPC	286	ret = indio_dev->info->read_event_value(indio_dev,
	287	this_attr->c, iio_ev_attr_type(this_attr),
	288	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	289	&val, &val2);
	290	if (ret < 0)
	291	return ret;
9fbfb4b3 SP	292	val_arr[0] = val;
	293	val_arr[1] = val2;
	294	return iio_format_value(buf, ret, 2, val_arr);
0a769a95 LPC	295	}
	296
	297	static ssize_t iio_ev_value_store(struct device *dev,
	298	struct device_attribute *attr,
	299	const char *buf,
	300	size_t len)
	301	{
e53f5ac5	302	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	303	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	304	int val, val2;
0a769a95 LPC	305	int ret;
0a769a95 LPC	306
cb955852	307	if (!indio_dev->info->write_event_value)
0a769a95 LPC	308	return -EINVAL;
0a769a95 LPC	309
cb955852 LPC	310	ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
	311	if (ret)
	312	return ret;
	313	ret = indio_dev->info->write_event_value(indio_dev,
	314	this_attr->c, iio_ev_attr_type(this_attr),
	315	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	316	val, val2);
0a769a95 LPC	317	if (ret < 0)
	318	return ret;
	319
	320	return len;
	321	}
	322
b4e3ac0a LPC	323	static int iio_device_add_event(struct iio_dev *indio_dev,
	324	const struct iio_chan_spec *chan, unsigned int spec_index,
	325	enum iio_event_type type, enum iio_event_direction dir,
	326	enum iio_shared_by shared_by, const unsigned long *mask)
	327	{
	328	ssize_t (show)(struct device , struct device_attribute , char );
	329	ssize_t (store)(struct device , struct device_attribute *,
	330	const char *, size_t);
	331	unsigned int attrcount = 0;
	332	unsigned int i;
	333	char *postfix;
	334	int ret;
	335
ef4b4856 JC	336	for_each_set_bit(i, mask, sizeof(mask)8) {
	337	if (i >= ARRAY_SIZE(iio_ev_info_text))
	338	return -EINVAL;
1843c2f3 IT	339	if (dir != IIO_EV_DIR_NONE)
	340	postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
	341	iio_ev_type_text[type],
	342	iio_ev_dir_text[dir],
	343	iio_ev_info_text[i]);
	344	else
	345	postfix = kasprintf(GFP_KERNEL, "%s_%s",
	346	iio_ev_type_text[type],
	347	iio_ev_info_text[i]);
b4e3ac0a LPC	348	if (postfix == NULL)
	349	return -ENOMEM;
	350
	351	if (i == IIO_EV_INFO_ENABLE) {
	352	show = iio_ev_state_show;
	353	store = iio_ev_state_store;
	354	} else {
	355	show = iio_ev_value_show;
	356	store = iio_ev_value_store;
	357	}
	358
	359	ret = __iio_add_chan_devattr(postfix, chan, show, store,
	360	(i << 16) \| spec_index, shared_by, &indio_dev->dev,
	361	&indio_dev->event_interface->dev_attr_list);
	362	kfree(postfix);
	363
78b33216 SP	364	if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
	365	continue;
	366
b4e3ac0a LPC	367	if (ret)
	368	return ret;
	369
	370	attrcount++;
	371	}
	372
	373	return attrcount;
	374	}
	375
cb955852	376	static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
b4e3ac0a LPC	377	struct iio_chan_spec const *chan)
	378	{
	379	int ret = 0, i, attrcount = 0;
	380	enum iio_event_direction dir;
	381	enum iio_event_type type;
	382
	383	for (i = 0; i < chan->num_event_specs; i++) {
	384	type = chan->event_spec[i].type;
	385	dir = chan->event_spec[i].dir;
	386
	387	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	388	IIO_SEPARATE, &chan->event_spec[i].mask_separate);
	389	if (ret < 0)
92825ff9	390	return ret;
b4e3ac0a LPC	391	attrcount += ret;
	392
	393	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	394	IIO_SHARED_BY_TYPE,
	395	&chan->event_spec[i].mask_shared_by_type);
	396	if (ret < 0)
92825ff9	397	return ret;
b4e3ac0a LPC	398	attrcount += ret;
	399
	400	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	401	IIO_SHARED_BY_DIR,
	402	&chan->event_spec[i].mask_shared_by_dir);
	403	if (ret < 0)
92825ff9	404	return ret;
b4e3ac0a LPC	405	attrcount += ret;
	406
	407	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	408	IIO_SHARED_BY_ALL,
	409	&chan->event_spec[i].mask_shared_by_all);
	410	if (ret < 0)
92825ff9	411	return ret;
b4e3ac0a LPC	412	attrcount += ret;
	413	}
	414	ret = attrcount;
b4e3ac0a LPC	415	return ret;
	416	}
	417
0a769a95 LPC	418	static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
	419	{
	420	int j, ret, attrcount = 0;
	421
2179aabe	422	/* Dynamically created from the channels array */
0a769a95 LPC	423	for (j = 0; j < indio_dev->num_channels; j++) {
	424	ret = iio_device_add_event_sysfs(indio_dev,
	425	&indio_dev->channels[j]);
	426	if (ret < 0)
e3db9ef6	427	return ret;
0a769a95 LPC	428	attrcount += ret;
	429	}
	430	return attrcount;
0a769a95 LPC	431	}
	432
	433	static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
	434	{
	435	int j;
	436
b4e3ac0a	437	for (j = 0; j < indio_dev->num_channels; j++) {
b4e3ac0a LPC	438	if (indio_dev->channels[j].num_event_specs != 0)
	439	return true;
	440	}
0a769a95 LPC	441	return false;
	442	}
	443
	444	static void iio_setup_ev_int(struct iio_event_interface *ev_int)
	445	{
2c00193f	446	INIT_KFIFO(ev_int->det_events);
0a769a95	447	init_waitqueue_head(&ev_int->wait);
b91accaf	448	mutex_init(&ev_int->read_lock);
0a769a95 LPC	449	}
	450
	451	static const char *iio_event_group_name = "events";
	452	int iio_device_register_eventset(struct iio_dev *indio_dev)
	453	{
	454	struct iio_dev_attr *p;
	455	int ret = 0, attrcount_orig = 0, attrcount, attrn;
	456	struct attribute **attr;
	457
	458	if (!(indio_dev->info->event_attrs \|\|
	459	iio_check_for_dynamic_events(indio_dev)))
	460	return 0;
	461
	462	indio_dev->event_interface =
	463	kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
92825ff9 HK	464	if (indio_dev->event_interface == NULL)
92825ff9 HK	465	return -ENOMEM;
0a769a95	466
46b24311 SH	467	INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
46b24311 SH	468
0a769a95 LPC	469	iio_setup_ev_int(indio_dev->event_interface);
	470	if (indio_dev->info->event_attrs != NULL) {
	471	attr = indio_dev->info->event_attrs->attrs;
	472	while (*attr++ != NULL)
	473	attrcount_orig++;
	474	}
	475	attrcount = attrcount_orig;
	476	if (indio_dev->channels) {
	477	ret = __iio_add_event_config_attrs(indio_dev);
	478	if (ret < 0)
	479	goto error_free_setup_event_lines;
	480	attrcount += ret;
	481	}
	482
	483	indio_dev->event_interface->group.name = iio_event_group_name;
	484	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
	485	sizeof(indio_dev->event_interface->group.attrs[0]),
	486	GFP_KERNEL);
	487	if (indio_dev->event_interface->group.attrs == NULL) {
	488	ret = -ENOMEM;
	489	goto error_free_setup_event_lines;
	490	}
	491	if (indio_dev->info->event_attrs)
	492	memcpy(indio_dev->event_interface->group.attrs,
	493	indio_dev->info->event_attrs->attrs,
	494	sizeof(indio_dev->event_interface->group.attrs[0])
	495	*attrcount_orig);
	496	attrn = attrcount_orig;
	497	/* Add all elements from the list. */
	498	list_for_each_entry(p,
	499	&indio_dev->event_interface->dev_attr_list,
	500	l)
	501	indio_dev->event_interface->group.attrs[attrn++] =
	502	&p->dev_attr.attr;
	503	indio_dev->groups[indio_dev->groupcounter++] =
	504	&indio_dev->event_interface->group;
	505
	506	return 0;
	507
	508	error_free_setup_event_lines:
84088ebd	509	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95	510	kfree(indio_dev->event_interface);
c1b03ab5	511	indio_dev->event_interface = NULL;
0a769a95 LPC	512	return ret;
	513	}
	514
d2f0a48f LPC	515	/**
	516	* iio_device_wakeup_eventset - Wakes up the event waitqueue
	517	* @indio_dev: The IIO device
	518	*
	519	* Wakes up the event waitqueue used for poll() and blocking read().
	520	* Should usually be called when the device is unregistered.
	521	*/
	522	void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
	523	{
	524	if (indio_dev->event_interface == NULL)
	525	return;
	526	wake_up(&indio_dev->event_interface->wait);
	527	}
	528
0a769a95 LPC	529	void iio_device_unregister_eventset(struct iio_dev *indio_dev)
	530	{
	531	if (indio_dev->event_interface == NULL)
	532	return;
84088ebd	533	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95 LPC	534	kfree(indio_dev->event_interface->group.attrs);
	535	kfree(indio_dev->event_interface);
	536	}