[mirror_ubuntu-zesty-kernel.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;
};

/**
 * 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
 **/
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;
	unsigned long flags;
	int copied;

	/* Does anyone care? */
	spin_lock_irqsave(&ev_int->wait.lock, flags);
	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_locked_poll(&ev_int->wait, POLLIN);
	}
	spin_unlock_irqrestore(&ev_int->wait.lock, flags);

	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);

	spin_lock_irq(&ev_int->wait.lock);
	if (!kfifo_is_empty(&ev_int->det_events))
		events = POLLIN | POLLRDNORM;
	spin_unlock_irq(&ev_int->wait.lock);

	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;

	spin_lock_irq(&ev_int->wait.lock);
	if (kfifo_is_empty(&ev_int->det_events)) {
		if (filep->f_flags & O_NONBLOCK) {
			ret = -EAGAIN;
			goto error_unlock;
		}
		/* Blocking on device; waiting for something to be there */
		ret = wait_event_interruptible_locked_irq(ev_int->wait,
					!kfifo_is_empty(&ev_int->det_events) ||
					indio_dev->info == NULL);
		if (ret)
			goto error_unlock;
		if (indio_dev->info == NULL) {
			ret = -ENODEV;
			goto error_unlock;
		}
		/* Single access device so no one else can get the data */
	}

	ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);

error_unlock:
	spin_unlock_irq(&ev_int->wait.lock);

	return ret ? ret : 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;

	spin_lock_irq(&ev_int->wait.lock);
	__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
	/*
	 * In order to maintain a clean state for reopening,
	 * clear out any awaiting events. The mask will prevent
	 * any new __iio_push_event calls running.
	 */
	kfifo_reset_out(&ev_int->det_events);
	spin_unlock_irq(&ev_int->wait.lock);

	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;

	spin_lock_irq(&ev_int->wait.lock);
	if (__test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
		spin_unlock_irq(&ev_int->wait.lock);
		return -EBUSY;
	}
	spin_unlock_irq(&ev_int->wait.lock);
	iio_device_get(indio_dev);

	fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
				indio_dev, O_RDONLY | O_CLOEXEC);
	if (fd < 0) {
		spin_lock_irq(&ev_int->wait.lock);
		__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
		spin_unlock_irq(&ev_int->wait.lock);
		iio_device_put(indio_dev);
	}
	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",
};

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;
	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;
	return iio_format_value(buf, ret, val, val2);
}

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)) {
		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)
			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);
}

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;
	43	};
	44
a7e57dce SK	45	/**
	46	* iio_push_event() - try to add event to the list for userspace reading
	47	* @indio_dev: IIO device structure
	48	* @ev_code: What event
	49	* @timestamp: When the event occurred
	50	**/
0a769a95 LPC	51	int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp)
	52	{
	53	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f	54	struct iio_event_data ev;
1b9dc91e	55	unsigned long flags;
2c00193f	56	int copied;
0a769a95 LPC	57
0a769a95 LPC	58	/* Does anyone care? */
1b9dc91e	59	spin_lock_irqsave(&ev_int->wait.lock, flags);
0a769a95	60	if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
0a769a95	61
2c00193f LPC	62	ev.id = ev_code;
	63	ev.timestamp = timestamp;
	64
498d319b	65	copied = kfifo_put(&ev_int->det_events, ev);
2c00193f	66	if (copied != 0)
e18045ed	67	wake_up_locked_poll(&ev_int->wait, POLLIN);
43ba1100	68	}
1b9dc91e	69	spin_unlock_irqrestore(&ev_int->wait.lock, flags);
0a769a95	70
2c00193f	71	return 0;
0a769a95 LPC	72	}
	73	EXPORT_SYMBOL(iio_push_event);
	74
e18045ed LPC	75	/**
	76	* iio_event_poll() - poll the event queue to find out if it has data
	77	*/
	78	static unsigned int iio_event_poll(struct file *filep,
	79	struct poll_table_struct *wait)
	80	{
cadc2125 LPC	81	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	82	struct iio_event_interface *ev_int = indio_dev->event_interface;
e18045ed LPC	83	unsigned int events = 0;
e18045ed LPC	84
f18e7a06 LPC	85	if (!indio_dev->info)
	86	return -ENODEV;
	87
e18045ed LPC	88	poll_wait(filep, &ev_int->wait, wait);
e18045ed LPC	89
1b9dc91e	90	spin_lock_irq(&ev_int->wait.lock);
e18045ed LPC	91	if (!kfifo_is_empty(&ev_int->det_events))
e18045ed LPC	92	events = POLLIN \| POLLRDNORM;
1b9dc91e	93	spin_unlock_irq(&ev_int->wait.lock);
e18045ed LPC	94
	95	return events;
	96	}
	97
0a769a95 LPC	98	static ssize_t iio_event_chrdev_read(struct file *filep,
	99	char __user *buf,
	100	size_t count,
	101	loff_t *f_ps)
	102	{
cadc2125 LPC	103	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	104	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f	105	unsigned int copied;
0a769a95 LPC	106	int ret;
0a769a95 LPC	107
f18e7a06 LPC	108	if (!indio_dev->info)
	109	return -ENODEV;
	110
2c00193f	111	if (count < sizeof(struct iio_event_data))
0a769a95 LPC	112	return -EINVAL;
0a769a95 LPC	113
1b9dc91e	114	spin_lock_irq(&ev_int->wait.lock);
2c00193f	115	if (kfifo_is_empty(&ev_int->det_events)) {
0a769a95 LPC	116	if (filep->f_flags & O_NONBLOCK) {
0a769a95 LPC	117	ret = -EAGAIN;
43ba1100	118	goto error_unlock;
0a769a95	119	}
0a769a95	120	/* Blocking on device; waiting for something to be there */
1b9dc91e	121	ret = wait_event_interruptible_locked_irq(ev_int->wait,
d2f0a48f LPC	122	!kfifo_is_empty(&ev_int->det_events) \|\|
d2f0a48f LPC	123	indio_dev->info == NULL);
0a769a95	124	if (ret)
43ba1100	125	goto error_unlock;
d2f0a48f LPC	126	if (indio_dev->info == NULL) {
	127	ret = -ENODEV;
	128	goto error_unlock;
	129	}
0a769a95	130	/* Single access device so no one else can get the data */
0a769a95 LPC	131	}
0a769a95 LPC	132
2c00193f	133	ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);
0a769a95	134
43ba1100	135	error_unlock:
1b9dc91e	136	spin_unlock_irq(&ev_int->wait.lock);
43ba1100	137
2c00193f	138	return ret ? ret : copied;
0a769a95 LPC	139	}
	140
	141	static int iio_event_chrdev_release(struct inode inode, struct file filep)
	142	{
cadc2125 LPC	143	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	144	struct iio_event_interface *ev_int = indio_dev->event_interface;
0a769a95	145
1b9dc91e	146	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	147	__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
0a769a95 LPC	148	/*
	149	* In order to maintain a clean state for reopening,
	150	* clear out any awaiting events. The mask will prevent
	151	* any new __iio_push_event calls running.
	152	*/
2c00193f	153	kfifo_reset_out(&ev_int->det_events);
1b9dc91e	154	spin_unlock_irq(&ev_int->wait.lock);
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
1b9dc91e	177	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	178	if (__test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
1b9dc91e	179	spin_unlock_irq(&ev_int->wait.lock);
0a769a95 LPC	180	return -EBUSY;
0a769a95 LPC	181	}
1b9dc91e	182	spin_unlock_irq(&ev_int->wait.lock);
cadc2125 LPC	183	iio_device_get(indio_dev);
	184
	185	fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
e2aad1d5	186	indio_dev, O_RDONLY \| O_CLOEXEC);
0a769a95	187	if (fd < 0) {
1b9dc91e	188	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	189	__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
1b9dc91e	190	spin_unlock_irq(&ev_int->wait.lock);
cadc2125	191	iio_device_put(indio_dev);
0a769a95 LPC	192	}
	193	return fd;
	194	}
	195
	196	static const char * const iio_ev_type_text[] = {
	197	[IIO_EV_TYPE_THRESH] = "thresh",
	198	[IIO_EV_TYPE_MAG] = "mag",
	199	[IIO_EV_TYPE_ROC] = "roc",
	200	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
	201	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
	202	};
	203
	204	static const char * const iio_ev_dir_text[] = {
	205	[IIO_EV_DIR_EITHER] = "either",
	206	[IIO_EV_DIR_RISING] = "rising",
	207	[IIO_EV_DIR_FALLING] = "falling"
	208	};
	209
b4e3ac0a LPC	210	static const char * const iio_ev_info_text[] = {
	211	[IIO_EV_INFO_ENABLE] = "en",
	212	[IIO_EV_INFO_VALUE] = "value",
ec6670ae	213	[IIO_EV_INFO_HYSTERESIS] = "hysteresis",
b4e3ac0a LPC	214	};
	215
	216	static enum iio_event_direction iio_ev_attr_dir(struct iio_dev_attr *attr)
	217	{
	218	return attr->c->event_spec[attr->address & 0xffff].dir;
	219	}
	220
	221	static enum iio_event_type iio_ev_attr_type(struct iio_dev_attr *attr)
	222	{
	223	return attr->c->event_spec[attr->address & 0xffff].type;
	224	}
	225
	226	static enum iio_event_info iio_ev_attr_info(struct iio_dev_attr *attr)
	227	{
	228	return (attr->address >> 16) & 0xffff;
	229	}
	230
0a769a95 LPC	231	static ssize_t iio_ev_state_store(struct device *dev,
	232	struct device_attribute *attr,
	233	const char *buf,
	234	size_t len)
	235	{
e53f5ac5	236	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	237	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	238	int ret;
	239	bool val;
	240
	241	ret = strtobool(buf, &val);
	242	if (ret < 0)
	243	return ret;
	244
cb955852 LPC	245	ret = indio_dev->info->write_event_config(indio_dev,
	246	this_attr->c, iio_ev_attr_type(this_attr),
	247	iio_ev_attr_dir(this_attr), val);
b4e3ac0a	248
0a769a95 LPC	249	return (ret < 0) ? ret : len;
	250	}
	251
	252	static ssize_t iio_ev_state_show(struct device *dev,
	253	struct device_attribute *attr,
	254	char *buf)
	255	{
e53f5ac5	256	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	257	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	258	int val;
0a769a95	259
cb955852 LPC	260	val = indio_dev->info->read_event_config(indio_dev,
	261	this_attr->c, iio_ev_attr_type(this_attr),
	262	iio_ev_attr_dir(this_attr));
0a769a95 LPC	263	if (val < 0)
	264	return val;
	265	else
	266	return sprintf(buf, "%d\n", val);
	267	}
	268
	269	static ssize_t iio_ev_value_show(struct device *dev,
	270	struct device_attribute *attr,
	271	char *buf)
	272	{
e53f5ac5	273	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	274	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a LPC	275	int val, val2;
b4e3ac0a LPC	276	int ret;
0a769a95	277
cb955852 LPC	278	ret = indio_dev->info->read_event_value(indio_dev,
	279	this_attr->c, iio_ev_attr_type(this_attr),
	280	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	281	&val, &val2);
	282	if (ret < 0)
	283	return ret;
	284	return iio_format_value(buf, ret, val, val2);
0a769a95 LPC	285	}
	286
	287	static ssize_t iio_ev_value_store(struct device *dev,
	288	struct device_attribute *attr,
	289	const char *buf,
	290	size_t len)
	291	{
e53f5ac5	292	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	293	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	294	int val, val2;
0a769a95 LPC	295	int ret;
0a769a95 LPC	296
cb955852	297	if (!indio_dev->info->write_event_value)
0a769a95 LPC	298	return -EINVAL;
0a769a95 LPC	299
cb955852 LPC	300	ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
	301	if (ret)
	302	return ret;
	303	ret = indio_dev->info->write_event_value(indio_dev,
	304	this_attr->c, iio_ev_attr_type(this_attr),
	305	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	306	val, val2);
0a769a95 LPC	307	if (ret < 0)
	308	return ret;
	309
	310	return len;
	311	}
	312
b4e3ac0a LPC	313	static int iio_device_add_event(struct iio_dev *indio_dev,
	314	const struct iio_chan_spec *chan, unsigned int spec_index,
	315	enum iio_event_type type, enum iio_event_direction dir,
	316	enum iio_shared_by shared_by, const unsigned long *mask)
	317	{
	318	ssize_t (show)(struct device , struct device_attribute , char );
	319	ssize_t (store)(struct device , struct device_attribute *,
	320	const char *, size_t);
	321	unsigned int attrcount = 0;
	322	unsigned int i;
	323	char *postfix;
	324	int ret;
	325
	326	for_each_set_bit(i, mask, sizeof(*mask)) {
	327	postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
	328	iio_ev_type_text[type], iio_ev_dir_text[dir],
	329	iio_ev_info_text[i]);
	330	if (postfix == NULL)
	331	return -ENOMEM;
	332
	333	if (i == IIO_EV_INFO_ENABLE) {
	334	show = iio_ev_state_show;
	335	store = iio_ev_state_store;
	336	} else {
	337	show = iio_ev_value_show;
	338	store = iio_ev_value_store;
	339	}
	340
	341	ret = __iio_add_chan_devattr(postfix, chan, show, store,
	342	(i << 16) \| spec_index, shared_by, &indio_dev->dev,
	343	&indio_dev->event_interface->dev_attr_list);
	344	kfree(postfix);
	345
	346	if (ret)
	347	return ret;
	348
	349	attrcount++;
	350	}
	351
	352	return attrcount;
	353	}
	354
cb955852	355	static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
b4e3ac0a LPC	356	struct iio_chan_spec const *chan)
	357	{
	358	int ret = 0, i, attrcount = 0;
	359	enum iio_event_direction dir;
	360	enum iio_event_type type;
	361
	362	for (i = 0; i < chan->num_event_specs; i++) {
	363	type = chan->event_spec[i].type;
	364	dir = chan->event_spec[i].dir;
	365
	366	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	367	IIO_SEPARATE, &chan->event_spec[i].mask_separate);
	368	if (ret < 0)
92825ff9	369	return ret;
b4e3ac0a LPC	370	attrcount += ret;
	371
	372	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	373	IIO_SHARED_BY_TYPE,
	374	&chan->event_spec[i].mask_shared_by_type);
	375	if (ret < 0)
92825ff9	376	return ret;
b4e3ac0a LPC	377	attrcount += ret;
	378
	379	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	380	IIO_SHARED_BY_DIR,
	381	&chan->event_spec[i].mask_shared_by_dir);
	382	if (ret < 0)
92825ff9	383	return ret;
b4e3ac0a LPC	384	attrcount += ret;
	385
	386	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	387	IIO_SHARED_BY_ALL,
	388	&chan->event_spec[i].mask_shared_by_all);
	389	if (ret < 0)
92825ff9	390	return ret;
b4e3ac0a LPC	391	attrcount += ret;
	392	}
	393	ret = attrcount;
b4e3ac0a LPC	394	return ret;
	395	}
	396
0a769a95 LPC	397	static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
	398	{
	399	int j, ret, attrcount = 0;
	400
0a769a95 LPC	401	/* Dynically created from the channels array */
	402	for (j = 0; j < indio_dev->num_channels; j++) {
	403	ret = iio_device_add_event_sysfs(indio_dev,
	404	&indio_dev->channels[j]);
	405	if (ret < 0)
e3db9ef6	406	return ret;
0a769a95 LPC	407	attrcount += ret;
	408	}
	409	return attrcount;
0a769a95 LPC	410	}
	411
	412	static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
	413	{
	414	int j;
	415
b4e3ac0a	416	for (j = 0; j < indio_dev->num_channels; j++) {
b4e3ac0a LPC	417	if (indio_dev->channels[j].num_event_specs != 0)
	418	return true;
	419	}
0a769a95 LPC	420	return false;
	421	}
	422
	423	static void iio_setup_ev_int(struct iio_event_interface *ev_int)
	424	{
2c00193f	425	INIT_KFIFO(ev_int->det_events);
0a769a95 LPC	426	init_waitqueue_head(&ev_int->wait);
	427	}
	428
	429	static const char *iio_event_group_name = "events";
	430	int iio_device_register_eventset(struct iio_dev *indio_dev)
	431	{
	432	struct iio_dev_attr *p;
	433	int ret = 0, attrcount_orig = 0, attrcount, attrn;
	434	struct attribute **attr;
	435
	436	if (!(indio_dev->info->event_attrs \|\|
	437	iio_check_for_dynamic_events(indio_dev)))
	438	return 0;
	439
	440	indio_dev->event_interface =
	441	kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
92825ff9 HK	442	if (indio_dev->event_interface == NULL)
92825ff9 HK	443	return -ENOMEM;
0a769a95	444
46b24311 SH	445	INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
46b24311 SH	446
0a769a95 LPC	447	iio_setup_ev_int(indio_dev->event_interface);
	448	if (indio_dev->info->event_attrs != NULL) {
	449	attr = indio_dev->info->event_attrs->attrs;
	450	while (*attr++ != NULL)
	451	attrcount_orig++;
	452	}
	453	attrcount = attrcount_orig;
	454	if (indio_dev->channels) {
	455	ret = __iio_add_event_config_attrs(indio_dev);
	456	if (ret < 0)
	457	goto error_free_setup_event_lines;
	458	attrcount += ret;
	459	}
	460
	461	indio_dev->event_interface->group.name = iio_event_group_name;
	462	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
	463	sizeof(indio_dev->event_interface->group.attrs[0]),
	464	GFP_KERNEL);
	465	if (indio_dev->event_interface->group.attrs == NULL) {
	466	ret = -ENOMEM;
	467	goto error_free_setup_event_lines;
	468	}
	469	if (indio_dev->info->event_attrs)
	470	memcpy(indio_dev->event_interface->group.attrs,
	471	indio_dev->info->event_attrs->attrs,
	472	sizeof(indio_dev->event_interface->group.attrs[0])
	473	*attrcount_orig);
	474	attrn = attrcount_orig;
	475	/* Add all elements from the list. */
	476	list_for_each_entry(p,
	477	&indio_dev->event_interface->dev_attr_list,
	478	l)
	479	indio_dev->event_interface->group.attrs[attrn++] =
	480	&p->dev_attr.attr;
	481	indio_dev->groups[indio_dev->groupcounter++] =
	482	&indio_dev->event_interface->group;
	483
	484	return 0;
	485
	486	error_free_setup_event_lines:
84088ebd	487	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95	488	kfree(indio_dev->event_interface);
0a769a95 LPC	489	return ret;
	490	}
	491
d2f0a48f LPC	492	/**
	493	* iio_device_wakeup_eventset - Wakes up the event waitqueue
	494	* @indio_dev: The IIO device
	495	*
	496	* Wakes up the event waitqueue used for poll() and blocking read().
	497	* Should usually be called when the device is unregistered.
	498	*/
	499	void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
	500	{
	501	if (indio_dev->event_interface == NULL)
	502	return;
	503	wake_up(&indio_dev->event_interface->wait);
	504	}
	505
0a769a95 LPC	506	void iio_device_unregister_eventset(struct iio_dev *indio_dev)
	507	{
	508	if (indio_dev->event_interface == NULL)
	509	return;
84088ebd	510	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95 LPC	511	kfree(indio_dev->event_interface->group.attrs);
	512	kfree(indio_dev->event_interface);
	513	}