[deliverable/linux.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
 */
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
 */
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 -ENODEV;

	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",
};

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",
};

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;
		postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
				iio_ev_type_text[type], iio_ev_dir_text[dir],
				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;

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