[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
 */
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",
	[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
	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",
27be8423	200	[IIO_EV_TYPE_CHANGE] = "change",
0a769a95 LPC	201	};
	202
	203	static const char * const iio_ev_dir_text[] = {
	204	[IIO_EV_DIR_EITHER] = "either",
	205	[IIO_EV_DIR_RISING] = "rising",
	206	[IIO_EV_DIR_FALLING] = "falling"
	207	};
	208
b4e3ac0a LPC	209	static const char * const iio_ev_info_text[] = {
	210	[IIO_EV_INFO_ENABLE] = "en",
	211	[IIO_EV_INFO_VALUE] = "value",
ec6670ae	212	[IIO_EV_INFO_HYSTERESIS] = "hysteresis",
77a533c7	213	[IIO_EV_INFO_PERIOD] = "period",
3f7f642b MF	214	[IIO_EV_INFO_HIGH_PASS_FILTER_3DB] = "high_pass_filter_3db",
3f7f642b MF	215	[IIO_EV_INFO_LOW_PASS_FILTER_3DB] = "low_pass_filter_3db",
b4e3ac0a LPC	216	};
	217
	218	static enum iio_event_direction iio_ev_attr_dir(struct iio_dev_attr *attr)
	219	{
	220	return attr->c->event_spec[attr->address & 0xffff].dir;
	221	}
	222
	223	static enum iio_event_type iio_ev_attr_type(struct iio_dev_attr *attr)
	224	{
	225	return attr->c->event_spec[attr->address & 0xffff].type;
	226	}
	227
	228	static enum iio_event_info iio_ev_attr_info(struct iio_dev_attr *attr)
	229	{
	230	return (attr->address >> 16) & 0xffff;
	231	}
	232
0a769a95 LPC	233	static ssize_t iio_ev_state_store(struct device *dev,
	234	struct device_attribute *attr,
	235	const char *buf,
	236	size_t len)
	237	{
e53f5ac5	238	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	239	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	240	int ret;
	241	bool val;
	242
	243	ret = strtobool(buf, &val);
	244	if (ret < 0)
	245	return ret;
	246
cb955852 LPC	247	ret = indio_dev->info->write_event_config(indio_dev,
	248	this_attr->c, iio_ev_attr_type(this_attr),
	249	iio_ev_attr_dir(this_attr), val);
b4e3ac0a	250
0a769a95 LPC	251	return (ret < 0) ? ret : len;
	252	}
	253
	254	static ssize_t iio_ev_state_show(struct device *dev,
	255	struct device_attribute *attr,
	256	char *buf)
	257	{
e53f5ac5	258	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	259	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	260	int val;
0a769a95	261
cb955852 LPC	262	val = indio_dev->info->read_event_config(indio_dev,
	263	this_attr->c, iio_ev_attr_type(this_attr),
	264	iio_ev_attr_dir(this_attr));
0a769a95 LPC	265	if (val < 0)
	266	return val;
	267	else
	268	return sprintf(buf, "%d\n", val);
	269	}
	270
	271	static ssize_t iio_ev_value_show(struct device *dev,
	272	struct device_attribute *attr,
	273	char *buf)
	274	{
e53f5ac5	275	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	276	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
9fbfb4b3	277	int val, val2, val_arr[2];
b4e3ac0a	278	int ret;
0a769a95	279
cb955852 LPC	280	ret = indio_dev->info->read_event_value(indio_dev,
	281	this_attr->c, iio_ev_attr_type(this_attr),
	282	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	283	&val, &val2);
	284	if (ret < 0)
	285	return ret;
9fbfb4b3 SP	286	val_arr[0] = val;
	287	val_arr[1] = val2;
	288	return iio_format_value(buf, ret, 2, val_arr);
0a769a95 LPC	289	}
	290
	291	static ssize_t iio_ev_value_store(struct device *dev,
	292	struct device_attribute *attr,
	293	const char *buf,
	294	size_t len)
	295	{
e53f5ac5	296	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	297	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	298	int val, val2;
0a769a95 LPC	299	int ret;
0a769a95 LPC	300
cb955852	301	if (!indio_dev->info->write_event_value)
0a769a95 LPC	302	return -EINVAL;
0a769a95 LPC	303
cb955852 LPC	304	ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
	305	if (ret)
	306	return ret;
	307	ret = indio_dev->info->write_event_value(indio_dev,
	308	this_attr->c, iio_ev_attr_type(this_attr),
	309	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	310	val, val2);
0a769a95 LPC	311	if (ret < 0)
	312	return ret;
	313
	314	return len;
	315	}
	316
b4e3ac0a LPC	317	static int iio_device_add_event(struct iio_dev *indio_dev,
	318	const struct iio_chan_spec *chan, unsigned int spec_index,
	319	enum iio_event_type type, enum iio_event_direction dir,
	320	enum iio_shared_by shared_by, const unsigned long *mask)
	321	{
	322	ssize_t (show)(struct device , struct device_attribute , char );
	323	ssize_t (store)(struct device , struct device_attribute *,
	324	const char *, size_t);
	325	unsigned int attrcount = 0;
	326	unsigned int i;
	327	char *postfix;
	328	int ret;
	329
ef4b4856 JC	330	for_each_set_bit(i, mask, sizeof(mask)8) {
	331	if (i >= ARRAY_SIZE(iio_ev_info_text))
	332	return -EINVAL;
1843c2f3 IT	333	if (dir != IIO_EV_DIR_NONE)
	334	postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
	335	iio_ev_type_text[type],
	336	iio_ev_dir_text[dir],
	337	iio_ev_info_text[i]);
	338	else
	339	postfix = kasprintf(GFP_KERNEL, "%s_%s",
	340	iio_ev_type_text[type],
	341	iio_ev_info_text[i]);
b4e3ac0a LPC	342	if (postfix == NULL)
	343	return -ENOMEM;
	344
	345	if (i == IIO_EV_INFO_ENABLE) {
	346	show = iio_ev_state_show;
	347	store = iio_ev_state_store;
	348	} else {
	349	show = iio_ev_value_show;
	350	store = iio_ev_value_store;
	351	}
	352
	353	ret = __iio_add_chan_devattr(postfix, chan, show, store,
	354	(i << 16) \| spec_index, shared_by, &indio_dev->dev,
	355	&indio_dev->event_interface->dev_attr_list);
	356	kfree(postfix);
	357
78b33216 SP	358	if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
	359	continue;
	360
b4e3ac0a LPC	361	if (ret)
	362	return ret;
	363
	364	attrcount++;
	365	}
	366
	367	return attrcount;
	368	}
	369
cb955852	370	static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
b4e3ac0a LPC	371	struct iio_chan_spec const *chan)
	372	{
	373	int ret = 0, i, attrcount = 0;
	374	enum iio_event_direction dir;
	375	enum iio_event_type type;
	376
	377	for (i = 0; i < chan->num_event_specs; i++) {
	378	type = chan->event_spec[i].type;
	379	dir = chan->event_spec[i].dir;
	380
	381	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	382	IIO_SEPARATE, &chan->event_spec[i].mask_separate);
	383	if (ret < 0)
92825ff9	384	return ret;
b4e3ac0a LPC	385	attrcount += ret;
	386
	387	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	388	IIO_SHARED_BY_TYPE,
	389	&chan->event_spec[i].mask_shared_by_type);
	390	if (ret < 0)
92825ff9	391	return ret;
b4e3ac0a LPC	392	attrcount += ret;
	393
	394	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	395	IIO_SHARED_BY_DIR,
	396	&chan->event_spec[i].mask_shared_by_dir);
	397	if (ret < 0)
92825ff9	398	return ret;
b4e3ac0a LPC	399	attrcount += ret;
	400
	401	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	402	IIO_SHARED_BY_ALL,
	403	&chan->event_spec[i].mask_shared_by_all);
	404	if (ret < 0)
92825ff9	405	return ret;
b4e3ac0a LPC	406	attrcount += ret;
	407	}
	408	ret = attrcount;
b4e3ac0a LPC	409	return ret;
	410	}
	411
0a769a95 LPC	412	static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
	413	{
	414	int j, ret, attrcount = 0;
	415
2179aabe	416	/* Dynamically created from the channels array */
0a769a95 LPC	417	for (j = 0; j < indio_dev->num_channels; j++) {
	418	ret = iio_device_add_event_sysfs(indio_dev,
	419	&indio_dev->channels[j]);
	420	if (ret < 0)
e3db9ef6	421	return ret;
0a769a95 LPC	422	attrcount += ret;
	423	}
	424	return attrcount;
0a769a95 LPC	425	}
	426
	427	static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
	428	{
	429	int j;
	430
b4e3ac0a	431	for (j = 0; j < indio_dev->num_channels; j++) {
b4e3ac0a LPC	432	if (indio_dev->channels[j].num_event_specs != 0)
	433	return true;
	434	}
0a769a95 LPC	435	return false;
	436	}
	437
	438	static void iio_setup_ev_int(struct iio_event_interface *ev_int)
	439	{
2c00193f	440	INIT_KFIFO(ev_int->det_events);
0a769a95	441	init_waitqueue_head(&ev_int->wait);
b91accaf	442	mutex_init(&ev_int->read_lock);
0a769a95 LPC	443	}
	444
	445	static const char *iio_event_group_name = "events";
	446	int iio_device_register_eventset(struct iio_dev *indio_dev)
	447	{
	448	struct iio_dev_attr *p;
	449	int ret = 0, attrcount_orig = 0, attrcount, attrn;
	450	struct attribute **attr;
	451
	452	if (!(indio_dev->info->event_attrs \|\|
	453	iio_check_for_dynamic_events(indio_dev)))
	454	return 0;
	455
	456	indio_dev->event_interface =
	457	kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
92825ff9 HK	458	if (indio_dev->event_interface == NULL)
92825ff9 HK	459	return -ENOMEM;
0a769a95	460
46b24311 SH	461	INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
46b24311 SH	462
0a769a95 LPC	463	iio_setup_ev_int(indio_dev->event_interface);
	464	if (indio_dev->info->event_attrs != NULL) {
	465	attr = indio_dev->info->event_attrs->attrs;
	466	while (*attr++ != NULL)
	467	attrcount_orig++;
	468	}
	469	attrcount = attrcount_orig;
	470	if (indio_dev->channels) {
	471	ret = __iio_add_event_config_attrs(indio_dev);
	472	if (ret < 0)
	473	goto error_free_setup_event_lines;
	474	attrcount += ret;
	475	}
	476
	477	indio_dev->event_interface->group.name = iio_event_group_name;
	478	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
	479	sizeof(indio_dev->event_interface->group.attrs[0]),
	480	GFP_KERNEL);
	481	if (indio_dev->event_interface->group.attrs == NULL) {
	482	ret = -ENOMEM;
	483	goto error_free_setup_event_lines;
	484	}
	485	if (indio_dev->info->event_attrs)
	486	memcpy(indio_dev->event_interface->group.attrs,
	487	indio_dev->info->event_attrs->attrs,
	488	sizeof(indio_dev->event_interface->group.attrs[0])
	489	*attrcount_orig);
	490	attrn = attrcount_orig;
	491	/* Add all elements from the list. */
	492	list_for_each_entry(p,
	493	&indio_dev->event_interface->dev_attr_list,
	494	l)
	495	indio_dev->event_interface->group.attrs[attrn++] =
	496	&p->dev_attr.attr;
	497	indio_dev->groups[indio_dev->groupcounter++] =
	498	&indio_dev->event_interface->group;
	499
	500	return 0;
	501
	502	error_free_setup_event_lines:
84088ebd	503	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95	504	kfree(indio_dev->event_interface);
c1b03ab5	505	indio_dev->event_interface = NULL;
0a769a95 LPC	506	return ret;
	507	}
	508
d2f0a48f LPC	509	/**
	510	* iio_device_wakeup_eventset - Wakes up the event waitqueue
	511	* @indio_dev: The IIO device
	512	*
	513	* Wakes up the event waitqueue used for poll() and blocking read().
	514	* Should usually be called when the device is unregistered.
	515	*/
	516	void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
	517	{
	518	if (indio_dev->event_interface == NULL)
	519	return;
	520	wake_up(&indio_dev->event_interface->wait);
	521	}
	522
0a769a95 LPC	523	void iio_device_unregister_eventset(struct iio_dev *indio_dev)
	524	{
	525	if (indio_dev->event_interface == NULL)
	526	return;
84088ebd	527	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95 LPC	528	kfree(indio_dev->event_interface->group.attrs);
	529	kfree(indio_dev->event_interface);
	530	}