[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
 * @read_lock:		lock to protect kfifo read operations
 */
struct iio_event_interface {
	wait_queue_head_t	wait;
	DECLARE_KFIFO(det_events, struct iio_event_data, 16);

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

bool iio_event_enabled(const struct iio_event_interface *ev_int)
{
	return !!test_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
}

/**
 * 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 (iio_event_enabled(ev_int)) {

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

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

	return 0;
}
EXPORT_SYMBOL(iio_push_event);

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

	if (!indio_dev->info)
		return events;

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

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

	return events;
}

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

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

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

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

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

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

		if (ret)
			return ret;

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

	} while (copied == 0);

	return copied;
}

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

	clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);

	iio_device_put(indio_dev);

	return 0;
}

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

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

	if (ev_int == NULL)
		return -ENODEV;

	fd = mutex_lock_interruptible(&indio_dev->mlock);
	if (fd)
		return fd;

	if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
		fd = -EBUSY;
		goto unlock;
	}

	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);
	}

unlock:
	mutex_unlock(&indio_dev->mlock);
	return fd;
}

static const char * const iio_ev_type_text[] = {
	[IIO_EV_TYPE_THRESH] = "thresh",
	[IIO_EV_TYPE_MAG] = "mag",
	[IIO_EV_TYPE_ROC] = "roc",
	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
	[IIO_EV_TYPE_CHANGE] = "change",
};

static const char * const iio_ev_dir_text[] = {
	[IIO_EV_DIR_EITHER] = "either",
	[IIO_EV_DIR_RISING] = "rising",
	[IIO_EV_DIR_FALLING] = "falling"
};

static const char * const iio_ev_info_text[] = {
	[IIO_EV_INFO_ENABLE] = "en",
	[IIO_EV_INFO_VALUE] = "value",
	[IIO_EV_INFO_HYSTERESIS] = "hysteresis",
	[IIO_EV_INFO_PERIOD] = "period",
	[IIO_EV_INFO_HIGH_PASS_FILTER_3DB] = "high_pass_filter_3db",
	[IIO_EV_INFO_LOW_PASS_FILTER_3DB] = "low_pass_filter_3db",
};

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

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

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

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

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

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

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

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

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

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

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

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

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

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

	return len;
}

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

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

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

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

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

		if (ret)
			return ret;

		attrcount++;
	}

	return attrcount;
}

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

	return 0;

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

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

void iio_device_unregister_eventset(struct iio_dev *indio_dev)
{
	if (indio_dev->event_interface == NULL)
		return;
	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
	kfree(indio_dev->event_interface->group.attrs);
	kfree(indio_dev->event_interface);
}
Commit	Line	Data
0a769a95 LPC	1	/* Industrial I/O event handling
	2	*
	3	* Copyright (c) 2008 Jonathan Cameron
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License version 2 as published by
	7	* the Free Software Foundation.
	8	*
	9	* Based on elements of hwmon and input subsystems.
	10	*/
	11
	12	#include <linux/anon_inodes.h>
	13	#include <linux/device.h>
	14	#include <linux/fs.h>
	15	#include <linux/kernel.h>
2c00193f	16	#include <linux/kfifo.h>
0a769a95	17	#include <linux/module.h>
e18045ed	18	#include <linux/poll.h>
0a769a95 LPC	19	#include <linux/sched.h>
	20	#include <linux/slab.h>
	21	#include <linux/uaccess.h>
	22	#include <linux/wait.h>
06458e27	23	#include <linux/iio/iio.h>
0a769a95	24	#include "iio_core.h"
06458e27 JC	25	#include <linux/iio/sysfs.h>
06458e27 JC	26	#include <linux/iio/events.h>
0a769a95	27
0a769a95 LPC	28	/**
	29	* struct iio_event_interface - chrdev interface for an event line
	30	* @wait: wait queue to allow blocking reads of events
0a769a95	31	* @det_events: list of detected events
0a769a95 LPC	32	* @dev_attr_list: list of event interface sysfs attribute
	33	* @flags: file operations related flags including busy flag.
	34	* @group: event interface sysfs attribute group
a316c01d	35	* @read_lock: lock to protect kfifo read operations
0a769a95 LPC	36	*/
	37	struct iio_event_interface {
	38	wait_queue_head_t wait;
2c00193f LPC	39	DECLARE_KFIFO(det_events, struct iio_event_data, 16);
2c00193f LPC	40
0a769a95 LPC	41	struct list_head dev_attr_list;
	42	unsigned long flags;
	43	struct attribute_group group;
b91accaf	44	struct mutex read_lock;
0a769a95 LPC	45	};
0a769a95 LPC	46
bc2b7dab GB	47	bool iio_event_enabled(const struct iio_event_interface *ev_int)
	48	{
	49	return !!test_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
	50	}
	51
a7e57dce SK	52	/**
	53	* iio_push_event() - try to add event to the list for userspace reading
	54	* @indio_dev: IIO device structure
	55	* @ev_code: What event
	56	* @timestamp: When the event occurred
b91accaf LPC	57	*
	58	* Note: The caller must make sure that this function is not running
	59	* concurrently for the same indio_dev more than once.
a7e57dce	60	**/
0a769a95 LPC	61	int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp)
	62	{
	63	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f LPC	64	struct iio_event_data ev;
2c00193f LPC	65	int copied;
0a769a95 LPC	66
0a769a95 LPC	67	/* Does anyone care? */
bc2b7dab	68	if (iio_event_enabled(ev_int)) {
0a769a95	69
2c00193f LPC	70	ev.id = ev_code;
	71	ev.timestamp = timestamp;
	72
498d319b	73	copied = kfifo_put(&ev_int->det_events, ev);
2c00193f	74	if (copied != 0)
b91accaf	75	wake_up_poll(&ev_int->wait, POLLIN);
43ba1100	76	}
0a769a95	77
2c00193f	78	return 0;
0a769a95 LPC	79	}
	80	EXPORT_SYMBOL(iio_push_event);
	81
e18045ed LPC	82	/**
e18045ed LPC	83	* iio_event_poll() - poll the event queue to find out if it has data
a316c01d CO	84	* @filep: File structure pointer to identify the device
	85	* @wait: Poll table pointer to add the wait queue on
	86	*
	87	* Return: (POLLIN \| POLLRDNORM) if data is available for reading
	88	* or a negative error code on failure
e18045ed LPC	89	*/
	90	static unsigned int iio_event_poll(struct file *filep,
	91	struct poll_table_struct *wait)
	92	{
cadc2125 LPC	93	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	94	struct iio_event_interface *ev_int = indio_dev->event_interface;
e18045ed LPC	95	unsigned int events = 0;
e18045ed LPC	96
f18e7a06	97	if (!indio_dev->info)
41d903c0	98	return events;
f18e7a06	99
e18045ed LPC	100	poll_wait(filep, &ev_int->wait, wait);
e18045ed LPC	101
e18045ed LPC	102	if (!kfifo_is_empty(&ev_int->det_events))
e18045ed LPC	103	events = POLLIN \| POLLRDNORM;
e18045ed LPC	104
	105	return events;
	106	}
	107
0a769a95 LPC	108	static ssize_t iio_event_chrdev_read(struct file *filep,
	109	char __user *buf,
	110	size_t count,
	111	loff_t *f_ps)
	112	{
cadc2125 LPC	113	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	114	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f	115	unsigned int copied;
0a769a95 LPC	116	int ret;
0a769a95 LPC	117
f18e7a06 LPC	118	if (!indio_dev->info)
	119	return -ENODEV;
	120
2c00193f	121	if (count < sizeof(struct iio_event_data))
0a769a95 LPC	122	return -EINVAL;
0a769a95 LPC	123
b91accaf LPC	124	do {
	125	if (kfifo_is_empty(&ev_int->det_events)) {
	126	if (filep->f_flags & O_NONBLOCK)
	127	return -EAGAIN;
	128
	129	ret = wait_event_interruptible(ev_int->wait,
d2f0a48f LPC	130	!kfifo_is_empty(&ev_int->det_events) \|\|
d2f0a48f LPC	131	indio_dev->info == NULL);
b91accaf LPC	132	if (ret)
	133	return ret;
	134	if (indio_dev->info == NULL)
	135	return -ENODEV;
d2f0a48f	136	}
0a769a95	137
b91accaf LPC	138	if (mutex_lock_interruptible(&ev_int->read_lock))
	139	return -ERESTARTSYS;
	140	ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);
	141	mutex_unlock(&ev_int->read_lock);
	142
	143	if (ret)
	144	return ret;
	145
	146	/*
	147	* If we couldn't read anything from the fifo (a different
	148	* thread might have been faster) we either return -EAGAIN if
	149	* the file descriptor is non-blocking, otherwise we go back to
	150	* sleep and wait for more data to arrive.
	151	*/
	152	if (copied == 0 && (filep->f_flags & O_NONBLOCK))
	153	return -EAGAIN;
0a769a95	154
b91accaf	155	} while (copied == 0);
43ba1100	156
b91accaf	157	return copied;
0a769a95 LPC	158	}
	159
	160	static int iio_event_chrdev_release(struct inode inode, struct file filep)
	161	{
cadc2125 LPC	162	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	163	struct iio_event_interface *ev_int = indio_dev->event_interface;
0a769a95	164
b91accaf	165	clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
0a769a95	166
cadc2125 LPC	167	iio_device_put(indio_dev);
cadc2125 LPC	168
0a769a95 LPC	169	return 0;
	170	}
	171
	172	static const struct file_operations iio_event_chrdev_fileops = {
	173	.read = iio_event_chrdev_read,
e18045ed	174	.poll = iio_event_poll,
0a769a95 LPC	175	.release = iio_event_chrdev_release,
	176	.owner = THIS_MODULE,
	177	.llseek = noop_llseek,
	178	};
	179
	180	int iio_event_getfd(struct iio_dev *indio_dev)
	181	{
	182	struct iio_event_interface *ev_int = indio_dev->event_interface;
	183	int fd;
	184
	185	if (ev_int == NULL)
	186	return -ENODEV;
	187
bc2b7dab GB	188	fd = mutex_lock_interruptible(&indio_dev->mlock);
	189	if (fd)
	190	return fd;
	191
	192	if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
	193	fd = -EBUSY;
	194	goto unlock;
	195	}
b91accaf	196
cadc2125 LPC	197	iio_device_get(indio_dev);
	198
	199	fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
e2aad1d5	200	indio_dev, O_RDONLY \| O_CLOEXEC);
0a769a95	201	if (fd < 0) {
b91accaf	202	clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
cadc2125	203	iio_device_put(indio_dev);
b91accaf LPC	204	} else {
b91accaf LPC	205	kfifo_reset_out(&ev_int->det_events);
0a769a95	206	}
b91accaf	207
bc2b7dab GB	208	unlock:
bc2b7dab GB	209	mutex_unlock(&indio_dev->mlock);
0a769a95 LPC	210	return fd;
	211	}
	212
	213	static const char * const iio_ev_type_text[] = {
	214	[IIO_EV_TYPE_THRESH] = "thresh",
	215	[IIO_EV_TYPE_MAG] = "mag",
	216	[IIO_EV_TYPE_ROC] = "roc",
	217	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
	218	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
27be8423	219	[IIO_EV_TYPE_CHANGE] = "change",
0a769a95 LPC	220	};
	221
	222	static const char * const iio_ev_dir_text[] = {
	223	[IIO_EV_DIR_EITHER] = "either",
	224	[IIO_EV_DIR_RISING] = "rising",
	225	[IIO_EV_DIR_FALLING] = "falling"
	226	};
	227
b4e3ac0a LPC	228	static const char * const iio_ev_info_text[] = {
	229	[IIO_EV_INFO_ENABLE] = "en",
	230	[IIO_EV_INFO_VALUE] = "value",
ec6670ae	231	[IIO_EV_INFO_HYSTERESIS] = "hysteresis",
77a533c7	232	[IIO_EV_INFO_PERIOD] = "period",
3f7f642b MF	233	[IIO_EV_INFO_HIGH_PASS_FILTER_3DB] = "high_pass_filter_3db",
3f7f642b MF	234	[IIO_EV_INFO_LOW_PASS_FILTER_3DB] = "low_pass_filter_3db",
b4e3ac0a LPC	235	};
	236
	237	static enum iio_event_direction iio_ev_attr_dir(struct iio_dev_attr *attr)
	238	{
	239	return attr->c->event_spec[attr->address & 0xffff].dir;
	240	}
	241
	242	static enum iio_event_type iio_ev_attr_type(struct iio_dev_attr *attr)
	243	{
	244	return attr->c->event_spec[attr->address & 0xffff].type;
	245	}
	246
	247	static enum iio_event_info iio_ev_attr_info(struct iio_dev_attr *attr)
	248	{
	249	return (attr->address >> 16) & 0xffff;
	250	}
	251
0a769a95 LPC	252	static ssize_t iio_ev_state_store(struct device *dev,
	253	struct device_attribute *attr,
	254	const char *buf,
	255	size_t len)
	256	{
e53f5ac5	257	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	258	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	259	int ret;
	260	bool val;
	261
	262	ret = strtobool(buf, &val);
	263	if (ret < 0)
	264	return ret;
	265
cb955852 LPC	266	ret = indio_dev->info->write_event_config(indio_dev,
	267	this_attr->c, iio_ev_attr_type(this_attr),
	268	iio_ev_attr_dir(this_attr), val);
b4e3ac0a	269
0a769a95 LPC	270	return (ret < 0) ? ret : len;
	271	}
	272
	273	static ssize_t iio_ev_state_show(struct device *dev,
	274	struct device_attribute *attr,
	275	char *buf)
	276	{
e53f5ac5	277	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	278	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	279	int val;
0a769a95	280
cb955852 LPC	281	val = indio_dev->info->read_event_config(indio_dev,
	282	this_attr->c, iio_ev_attr_type(this_attr),
	283	iio_ev_attr_dir(this_attr));
0a769a95 LPC	284	if (val < 0)
	285	return val;
	286	else
	287	return sprintf(buf, "%d\n", val);
	288	}
	289
	290	static ssize_t iio_ev_value_show(struct device *dev,
	291	struct device_attribute *attr,
	292	char *buf)
	293	{
e53f5ac5	294	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	295	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
9fbfb4b3	296	int val, val2, val_arr[2];
b4e3ac0a	297	int ret;
0a769a95	298
cb955852 LPC	299	ret = indio_dev->info->read_event_value(indio_dev,
	300	this_attr->c, iio_ev_attr_type(this_attr),
	301	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	302	&val, &val2);
	303	if (ret < 0)
	304	return ret;
9fbfb4b3 SP	305	val_arr[0] = val;
	306	val_arr[1] = val2;
	307	return iio_format_value(buf, ret, 2, val_arr);
0a769a95 LPC	308	}
	309
	310	static ssize_t iio_ev_value_store(struct device *dev,
	311	struct device_attribute *attr,
	312	const char *buf,
	313	size_t len)
	314	{
e53f5ac5	315	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	316	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	317	int val, val2;
0a769a95 LPC	318	int ret;
0a769a95 LPC	319
cb955852	320	if (!indio_dev->info->write_event_value)
0a769a95 LPC	321	return -EINVAL;
0a769a95 LPC	322
cb955852 LPC	323	ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
	324	if (ret)
	325	return ret;
	326	ret = indio_dev->info->write_event_value(indio_dev,
	327	this_attr->c, iio_ev_attr_type(this_attr),
	328	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	329	val, val2);
0a769a95 LPC	330	if (ret < 0)
	331	return ret;
	332
	333	return len;
	334	}
	335
b4e3ac0a LPC	336	static int iio_device_add_event(struct iio_dev *indio_dev,
	337	const struct iio_chan_spec *chan, unsigned int spec_index,
	338	enum iio_event_type type, enum iio_event_direction dir,
	339	enum iio_shared_by shared_by, const unsigned long *mask)
	340	{
	341	ssize_t (show)(struct device , struct device_attribute , char );
	342	ssize_t (store)(struct device , struct device_attribute *,
	343	const char *, size_t);
	344	unsigned int attrcount = 0;
	345	unsigned int i;
	346	char *postfix;
	347	int ret;
	348
ef4b4856 JC	349	for_each_set_bit(i, mask, sizeof(mask)8) {
	350	if (i >= ARRAY_SIZE(iio_ev_info_text))
	351	return -EINVAL;
1843c2f3 IT	352	if (dir != IIO_EV_DIR_NONE)
	353	postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
	354	iio_ev_type_text[type],
	355	iio_ev_dir_text[dir],
	356	iio_ev_info_text[i]);
	357	else
	358	postfix = kasprintf(GFP_KERNEL, "%s_%s",
	359	iio_ev_type_text[type],
	360	iio_ev_info_text[i]);
b4e3ac0a LPC	361	if (postfix == NULL)
	362	return -ENOMEM;
	363
	364	if (i == IIO_EV_INFO_ENABLE) {
	365	show = iio_ev_state_show;
	366	store = iio_ev_state_store;
	367	} else {
	368	show = iio_ev_value_show;
	369	store = iio_ev_value_store;
	370	}
	371
	372	ret = __iio_add_chan_devattr(postfix, chan, show, store,
	373	(i << 16) \| spec_index, shared_by, &indio_dev->dev,
	374	&indio_dev->event_interface->dev_attr_list);
	375	kfree(postfix);
	376
78b33216 SP	377	if ((ret == -EBUSY) && (shared_by != IIO_SEPARATE))
	378	continue;
	379
b4e3ac0a LPC	380	if (ret)
	381	return ret;
	382
	383	attrcount++;
	384	}
	385
	386	return attrcount;
	387	}
	388
cb955852	389	static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
b4e3ac0a LPC	390	struct iio_chan_spec const *chan)
	391	{
	392	int ret = 0, i, attrcount = 0;
	393	enum iio_event_direction dir;
	394	enum iio_event_type type;
	395
	396	for (i = 0; i < chan->num_event_specs; i++) {
	397	type = chan->event_spec[i].type;
	398	dir = chan->event_spec[i].dir;
	399
	400	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	401	IIO_SEPARATE, &chan->event_spec[i].mask_separate);
	402	if (ret < 0)
92825ff9	403	return ret;
b4e3ac0a LPC	404	attrcount += ret;
	405
	406	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	407	IIO_SHARED_BY_TYPE,
	408	&chan->event_spec[i].mask_shared_by_type);
	409	if (ret < 0)
92825ff9	410	return ret;
b4e3ac0a LPC	411	attrcount += ret;
	412
	413	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	414	IIO_SHARED_BY_DIR,
	415	&chan->event_spec[i].mask_shared_by_dir);
	416	if (ret < 0)
92825ff9	417	return ret;
b4e3ac0a LPC	418	attrcount += ret;
	419
	420	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	421	IIO_SHARED_BY_ALL,
	422	&chan->event_spec[i].mask_shared_by_all);
	423	if (ret < 0)
92825ff9	424	return ret;
b4e3ac0a LPC	425	attrcount += ret;
	426	}
	427	ret = attrcount;
b4e3ac0a LPC	428	return ret;
	429	}
	430
0a769a95 LPC	431	static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
	432	{
	433	int j, ret, attrcount = 0;
	434
2179aabe	435	/* Dynamically created from the channels array */
0a769a95 LPC	436	for (j = 0; j < indio_dev->num_channels; j++) {
	437	ret = iio_device_add_event_sysfs(indio_dev,
	438	&indio_dev->channels[j]);
	439	if (ret < 0)
e3db9ef6	440	return ret;
0a769a95 LPC	441	attrcount += ret;
	442	}
	443	return attrcount;
0a769a95 LPC	444	}
	445
	446	static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
	447	{
	448	int j;
	449
b4e3ac0a	450	for (j = 0; j < indio_dev->num_channels; j++) {
b4e3ac0a LPC	451	if (indio_dev->channels[j].num_event_specs != 0)
	452	return true;
	453	}
0a769a95 LPC	454	return false;
	455	}
	456
	457	static void iio_setup_ev_int(struct iio_event_interface *ev_int)
	458	{
2c00193f	459	INIT_KFIFO(ev_int->det_events);
0a769a95	460	init_waitqueue_head(&ev_int->wait);
b91accaf	461	mutex_init(&ev_int->read_lock);
0a769a95 LPC	462	}
	463
	464	static const char *iio_event_group_name = "events";
	465	int iio_device_register_eventset(struct iio_dev *indio_dev)
	466	{
	467	struct iio_dev_attr *p;
	468	int ret = 0, attrcount_orig = 0, attrcount, attrn;
	469	struct attribute **attr;
	470
	471	if (!(indio_dev->info->event_attrs \|\|
	472	iio_check_for_dynamic_events(indio_dev)))
	473	return 0;
	474
	475	indio_dev->event_interface =
	476	kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
92825ff9 HK	477	if (indio_dev->event_interface == NULL)
92825ff9 HK	478	return -ENOMEM;
0a769a95	479
46b24311 SH	480	INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
46b24311 SH	481
0a769a95 LPC	482	iio_setup_ev_int(indio_dev->event_interface);
	483	if (indio_dev->info->event_attrs != NULL) {
	484	attr = indio_dev->info->event_attrs->attrs;
	485	while (*attr++ != NULL)
	486	attrcount_orig++;
	487	}
	488	attrcount = attrcount_orig;
	489	if (indio_dev->channels) {
	490	ret = __iio_add_event_config_attrs(indio_dev);
	491	if (ret < 0)
	492	goto error_free_setup_event_lines;
	493	attrcount += ret;
	494	}
	495
	496	indio_dev->event_interface->group.name = iio_event_group_name;
	497	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
	498	sizeof(indio_dev->event_interface->group.attrs[0]),
	499	GFP_KERNEL);
	500	if (indio_dev->event_interface->group.attrs == NULL) {
	501	ret = -ENOMEM;
	502	goto error_free_setup_event_lines;
	503	}
	504	if (indio_dev->info->event_attrs)
	505	memcpy(indio_dev->event_interface->group.attrs,
	506	indio_dev->info->event_attrs->attrs,
	507	sizeof(indio_dev->event_interface->group.attrs[0])
	508	*attrcount_orig);
	509	attrn = attrcount_orig;
	510	/* Add all elements from the list. */
	511	list_for_each_entry(p,
	512	&indio_dev->event_interface->dev_attr_list,
	513	l)
	514	indio_dev->event_interface->group.attrs[attrn++] =
	515	&p->dev_attr.attr;
	516	indio_dev->groups[indio_dev->groupcounter++] =
	517	&indio_dev->event_interface->group;
	518
	519	return 0;
	520
	521	error_free_setup_event_lines:
84088ebd	522	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95	523	kfree(indio_dev->event_interface);
c1b03ab5	524	indio_dev->event_interface = NULL;
0a769a95 LPC	525	return ret;
	526	}
	527
d2f0a48f LPC	528	/**
	529	* iio_device_wakeup_eventset - Wakes up the event waitqueue
	530	* @indio_dev: The IIO device
	531	*
	532	* Wakes up the event waitqueue used for poll() and blocking read().
	533	* Should usually be called when the device is unregistered.
	534	*/
	535	void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
	536	{
	537	if (indio_dev->event_interface == NULL)
	538	return;
	539	wake_up(&indio_dev->event_interface->wait);
	540	}
	541
0a769a95 LPC	542	void iio_device_unregister_eventset(struct iio_dev *indio_dev)
	543	{
	544	if (indio_dev->event_interface == NULL)
	545	return;
84088ebd	546	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95 LPC	547	kfree(indio_dev->event_interface->group.attrs);
	548	kfree(indio_dev->event_interface);
	549	}