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

/* Industrial I/O event handling
 *
 * Copyright (c) 2008 Jonathan Cameron
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * Based on elements of hwmon and input subsystems.
 */

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

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

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

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;

	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 (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));
		if (ret)
			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 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->address,
						  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 = indio_dev->info->read_event_config(indio_dev,
						     this_attr->address);

	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, ret;

	ret = indio_dev->info->read_event_value(indio_dev,
						this_attr->address, &val);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", val);
}

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;
	int ret;

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

	ret = kstrtoint(buf, 10, &val);
	if (ret)
		return ret;

	ret = indio_dev->info->write_event_value(indio_dev, this_attr->address,
						 val);
	if (ret < 0)
		return ret;

	return len;
}

static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
				      struct iio_chan_spec const *chan)
{
	int ret = 0, i, attrcount = 0;
	u64 mask = 0;
	char *postfix;
	if (!chan->event_mask)
		return 0;

	for_each_set_bit(i, &chan->event_mask, sizeof(chan->event_mask)*8) {
		postfix = kasprintf(GFP_KERNEL, "%s_%s_en",
				    iio_ev_type_text[i/IIO_EV_DIR_MAX],
				    iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
		if (postfix == NULL) {
			ret = -ENOMEM;
			goto error_ret;
		}
		if (chan->modified)
			mask = IIO_MOD_EVENT_CODE(chan->type, 0, chan->channel2,
						  i/IIO_EV_DIR_MAX,
						  i%IIO_EV_DIR_MAX);
		else if (chan->differential)
			mask = IIO_EVENT_CODE(chan->type,
					      0, 0,
					      i%IIO_EV_DIR_MAX,
					      i/IIO_EV_DIR_MAX,
					      0,
					      chan->channel,
					      chan->channel2);
		else
			mask = IIO_UNMOD_EVENT_CODE(chan->type,
						    chan->channel,
						    i/IIO_EV_DIR_MAX,
						    i%IIO_EV_DIR_MAX);

		ret = __iio_add_chan_devattr(postfix,
					     chan,
					     &iio_ev_state_show,
					     iio_ev_state_store,
					     mask,
					     0,
					     &indio_dev->dev,
					     &indio_dev->event_interface->
					     dev_attr_list);
		kfree(postfix);
		if (ret)
			goto error_ret;
		attrcount++;
		postfix = kasprintf(GFP_KERNEL, "%s_%s_value",
				    iio_ev_type_text[i/IIO_EV_DIR_MAX],
				    iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
		if (postfix == NULL) {
			ret = -ENOMEM;
			goto error_ret;
		}
		ret = __iio_add_chan_devattr(postfix, chan,
					     iio_ev_value_show,
					     iio_ev_value_store,
					     mask,
					     0,
					     &indio_dev->dev,
					     &indio_dev->event_interface->
					     dev_attr_list);
		kfree(postfix);
		if (ret)
			goto error_ret;
		attrcount++;
	}
	ret = attrcount;
error_ret:
	return ret;
}

static inline void __iio_remove_event_config_attrs(struct iio_dev *indio_dev)
{
	struct iio_dev_attr *p, *n;
	list_for_each_entry_safe(p, n,
				 &indio_dev->event_interface->
				 dev_attr_list, l) {
		kfree(p->dev_attr.attr.name);
		kfree(p);
	}
}

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].event_mask != 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) {
		ret = -ENOMEM;
		goto error_ret;
	}

	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_remove_event_config_attrs(indio_dev);
	kfree(indio_dev->event_interface);
error_ret:

	return ret;
}

void iio_device_unregister_eventset(struct iio_dev *indio_dev)
{
	if (indio_dev->event_interface == NULL)
		return;
	__iio_remove_event_config_attrs(indio_dev);
	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
	45	int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp)
	46	{
	47	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f	48	struct iio_event_data ev;
1b9dc91e	49	unsigned long flags;
2c00193f	50	int copied;
0a769a95 LPC	51
0a769a95 LPC	52	/* Does anyone care? */
1b9dc91e	53	spin_lock_irqsave(&ev_int->wait.lock, flags);
0a769a95	54	if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
0a769a95	55
2c00193f LPC	56	ev.id = ev_code;
	57	ev.timestamp = timestamp;
	58
	59	copied = kfifo_put(&ev_int->det_events, &ev);
2c00193f	60	if (copied != 0)
e18045ed	61	wake_up_locked_poll(&ev_int->wait, POLLIN);
43ba1100	62	}
1b9dc91e	63	spin_unlock_irqrestore(&ev_int->wait.lock, flags);
0a769a95	64
2c00193f	65	return 0;
0a769a95 LPC	66	}
	67	EXPORT_SYMBOL(iio_push_event);
	68
e18045ed LPC	69	/**
	70	* iio_event_poll() - poll the event queue to find out if it has data
	71	*/
	72	static unsigned int iio_event_poll(struct file *filep,
	73	struct poll_table_struct *wait)
	74	{
cadc2125 LPC	75	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	76	struct iio_event_interface *ev_int = indio_dev->event_interface;
e18045ed LPC	77	unsigned int events = 0;
	78
	79	poll_wait(filep, &ev_int->wait, wait);
	80
1b9dc91e	81	spin_lock_irq(&ev_int->wait.lock);
e18045ed LPC	82	if (!kfifo_is_empty(&ev_int->det_events))
e18045ed LPC	83	events = POLLIN \| POLLRDNORM;
1b9dc91e	84	spin_unlock_irq(&ev_int->wait.lock);
e18045ed LPC	85
	86	return events;
	87	}
	88
0a769a95 LPC	89	static ssize_t iio_event_chrdev_read(struct file *filep,
	90	char __user *buf,
	91	size_t count,
	92	loff_t *f_ps)
	93	{
cadc2125 LPC	94	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	95	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f	96	unsigned int copied;
0a769a95 LPC	97	int ret;
0a769a95 LPC	98
2c00193f	99	if (count < sizeof(struct iio_event_data))
0a769a95 LPC	100	return -EINVAL;
0a769a95 LPC	101
1b9dc91e	102	spin_lock_irq(&ev_int->wait.lock);
2c00193f	103	if (kfifo_is_empty(&ev_int->det_events)) {
0a769a95 LPC	104	if (filep->f_flags & O_NONBLOCK) {
0a769a95 LPC	105	ret = -EAGAIN;
43ba1100	106	goto error_unlock;
0a769a95	107	}
0a769a95	108	/* Blocking on device; waiting for something to be there */
1b9dc91e	109	ret = wait_event_interruptible_locked_irq(ev_int->wait,
2c00193f	110	!kfifo_is_empty(&ev_int->det_events));
0a769a95	111	if (ret)
43ba1100	112	goto error_unlock;
0a769a95	113	/* Single access device so no one else can get the data */
0a769a95 LPC	114	}
0a769a95 LPC	115
2c00193f	116	ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);
0a769a95	117
43ba1100	118	error_unlock:
1b9dc91e	119	spin_unlock_irq(&ev_int->wait.lock);
43ba1100	120
2c00193f	121	return ret ? ret : copied;
0a769a95 LPC	122	}
	123
	124	static int iio_event_chrdev_release(struct inode inode, struct file filep)
	125	{
cadc2125 LPC	126	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	127	struct iio_event_interface *ev_int = indio_dev->event_interface;
0a769a95	128
1b9dc91e	129	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	130	__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
0a769a95 LPC	131	/*
	132	* In order to maintain a clean state for reopening,
	133	* clear out any awaiting events. The mask will prevent
	134	* any new __iio_push_event calls running.
	135	*/
2c00193f	136	kfifo_reset_out(&ev_int->det_events);
1b9dc91e	137	spin_unlock_irq(&ev_int->wait.lock);
0a769a95	138
cadc2125 LPC	139	iio_device_put(indio_dev);
cadc2125 LPC	140
0a769a95 LPC	141	return 0;
	142	}
	143
	144	static const struct file_operations iio_event_chrdev_fileops = {
	145	.read = iio_event_chrdev_read,
e18045ed	146	.poll = iio_event_poll,
0a769a95 LPC	147	.release = iio_event_chrdev_release,
	148	.owner = THIS_MODULE,
	149	.llseek = noop_llseek,
	150	};
	151
	152	int iio_event_getfd(struct iio_dev *indio_dev)
	153	{
	154	struct iio_event_interface *ev_int = indio_dev->event_interface;
	155	int fd;
	156
	157	if (ev_int == NULL)
	158	return -ENODEV;
	159
1b9dc91e	160	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	161	if (__test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
1b9dc91e	162	spin_unlock_irq(&ev_int->wait.lock);
0a769a95 LPC	163	return -EBUSY;
0a769a95 LPC	164	}
1b9dc91e	165	spin_unlock_irq(&ev_int->wait.lock);
cadc2125 LPC	166	iio_device_get(indio_dev);
	167
	168	fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
e2aad1d5	169	indio_dev, O_RDONLY \| O_CLOEXEC);
0a769a95	170	if (fd < 0) {
1b9dc91e	171	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	172	__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
1b9dc91e	173	spin_unlock_irq(&ev_int->wait.lock);
cadc2125	174	iio_device_put(indio_dev);
0a769a95 LPC	175	}
	176	return fd;
	177	}
	178
	179	static const char * const iio_ev_type_text[] = {
	180	[IIO_EV_TYPE_THRESH] = "thresh",
	181	[IIO_EV_TYPE_MAG] = "mag",
	182	[IIO_EV_TYPE_ROC] = "roc",
	183	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
	184	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
	185	};
	186
	187	static const char * const iio_ev_dir_text[] = {
	188	[IIO_EV_DIR_EITHER] = "either",
	189	[IIO_EV_DIR_RISING] = "rising",
	190	[IIO_EV_DIR_FALLING] = "falling"
	191	};
	192
	193	static ssize_t iio_ev_state_store(struct device *dev,
	194	struct device_attribute *attr,
	195	const char *buf,
	196	size_t len)
	197	{
e53f5ac5	198	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	199	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	200	int ret;
	201	bool val;
	202
	203	ret = strtobool(buf, &val);
	204	if (ret < 0)
	205	return ret;
	206
	207	ret = indio_dev->info->write_event_config(indio_dev,
	208	this_attr->address,
	209	val);
	210	return (ret < 0) ? ret : len;
	211	}
	212
	213	static ssize_t iio_ev_state_show(struct device *dev,
	214	struct device_attribute *attr,
	215	char *buf)
	216	{
e53f5ac5	217	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	218	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	219	int val = indio_dev->info->read_event_config(indio_dev,
	220	this_attr->address);
	221
	222	if (val < 0)
	223	return val;
	224	else
	225	return sprintf(buf, "%d\n", val);
	226	}
	227
	228	static ssize_t iio_ev_value_show(struct device *dev,
	229	struct device_attribute *attr,
	230	char *buf)
	231	{
e53f5ac5	232	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	233	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	234	int val, ret;
	235
	236	ret = indio_dev->info->read_event_value(indio_dev,
	237	this_attr->address, &val);
	238	if (ret < 0)
	239	return ret;
	240
	241	return sprintf(buf, "%d\n", val);
	242	}
	243
	244	static ssize_t iio_ev_value_store(struct device *dev,
	245	struct device_attribute *attr,
	246	const char *buf,
	247	size_t len)
	248	{
e53f5ac5	249	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	250	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
948ad205	251	int val;
0a769a95 LPC	252	int ret;
	253
	254	if (!indio_dev->info->write_event_value)
	255	return -EINVAL;
	256
948ad205	257	ret = kstrtoint(buf, 10, &val);
0a769a95 LPC	258	if (ret)
	259	return ret;
	260
	261	ret = indio_dev->info->write_event_value(indio_dev, this_attr->address,
	262	val);
	263	if (ret < 0)
	264	return ret;
	265
	266	return len;
	267	}
	268
	269	static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
	270	struct iio_chan_spec const *chan)
	271	{
	272	int ret = 0, i, attrcount = 0;
	273	u64 mask = 0;
	274	char *postfix;
	275	if (!chan->event_mask)
	276	return 0;
	277
	278	for_each_set_bit(i, &chan->event_mask, sizeof(chan->event_mask)*8) {
	279	postfix = kasprintf(GFP_KERNEL, "%s_%s_en",
	280	iio_ev_type_text[i/IIO_EV_DIR_MAX],
	281	iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
	282	if (postfix == NULL) {
	283	ret = -ENOMEM;
	284	goto error_ret;
	285	}
	286	if (chan->modified)
2b0774df	287	mask = IIO_MOD_EVENT_CODE(chan->type, 0, chan->channel2,
0a769a95 LPC	288	i/IIO_EV_DIR_MAX,
	289	i%IIO_EV_DIR_MAX);
	290	else if (chan->differential)
	291	mask = IIO_EVENT_CODE(chan->type,
	292	0, 0,
	293	i%IIO_EV_DIR_MAX,
	294	i/IIO_EV_DIR_MAX,
	295	0,
	296	chan->channel,
	297	chan->channel2);
	298	else
	299	mask = IIO_UNMOD_EVENT_CODE(chan->type,
	300	chan->channel,
	301	i/IIO_EV_DIR_MAX,
	302	i%IIO_EV_DIR_MAX);
	303
	304	ret = __iio_add_chan_devattr(postfix,
	305	chan,
	306	&iio_ev_state_show,
	307	iio_ev_state_store,
	308	mask,
	309	0,
	310	&indio_dev->dev,
	311	&indio_dev->event_interface->
	312	dev_attr_list);
	313	kfree(postfix);
	314	if (ret)
	315	goto error_ret;
	316	attrcount++;
	317	postfix = kasprintf(GFP_KERNEL, "%s_%s_value",
	318	iio_ev_type_text[i/IIO_EV_DIR_MAX],
	319	iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
	320	if (postfix == NULL) {
	321	ret = -ENOMEM;
	322	goto error_ret;
	323	}
	324	ret = __iio_add_chan_devattr(postfix, chan,
	325	iio_ev_value_show,
	326	iio_ev_value_store,
	327	mask,
	328	0,
	329	&indio_dev->dev,
	330	&indio_dev->event_interface->
	331	dev_attr_list);
	332	kfree(postfix);
	333	if (ret)
	334	goto error_ret;
	335	attrcount++;
	336	}
	337	ret = attrcount;
	338	error_ret:
	339	return ret;
	340	}
	341
	342	static inline void __iio_remove_event_config_attrs(struct iio_dev *indio_dev)
	343	{
	344	struct iio_dev_attr p, n;
	345	list_for_each_entry_safe(p, n,
	346	&indio_dev->event_interface->
	347	dev_attr_list, l) {
	348	kfree(p->dev_attr.attr.name);
	349	kfree(p);
	350	}
	351	}
352
353	static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
354	{
355	int j, ret, attrcount = 0;
356
0a769a95 LPC	357	/* Dynically created from the channels array */
	358	for (j = 0; j < indio_dev->num_channels; j++) {
	359	ret = iio_device_add_event_sysfs(indio_dev,
	360	&indio_dev->channels[j]);
	361	if (ret < 0)
e3db9ef6	362	return ret;
0a769a95 LPC	363	attrcount += ret;
	364	}
	365	return attrcount;
0a769a95 LPC	366	}
	367
	368	static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
	369	{
	370	int j;
	371
	372	for (j = 0; j < indio_dev->num_channels; j++)
	373	if (indio_dev->channels[j].event_mask != 0)
	374	return true;
	375	return false;
	376	}
	377
	378	static void iio_setup_ev_int(struct iio_event_interface *ev_int)
	379	{
2c00193f	380	INIT_KFIFO(ev_int->det_events);
0a769a95 LPC	381	init_waitqueue_head(&ev_int->wait);
	382	}
	383
	384	static const char *iio_event_group_name = "events";
	385	int iio_device_register_eventset(struct iio_dev *indio_dev)
	386	{
	387	struct iio_dev_attr *p;
	388	int ret = 0, attrcount_orig = 0, attrcount, attrn;
	389	struct attribute **attr;
	390
	391	if (!(indio_dev->info->event_attrs \|\|
	392	iio_check_for_dynamic_events(indio_dev)))
	393	return 0;
	394
	395	indio_dev->event_interface =
	396	kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
	397	if (indio_dev->event_interface == NULL) {
	398	ret = -ENOMEM;
	399	goto error_ret;
	400	}
	401
46b24311 SH	402	INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
46b24311 SH	403
0a769a95 LPC	404	iio_setup_ev_int(indio_dev->event_interface);
	405	if (indio_dev->info->event_attrs != NULL) {
	406	attr = indio_dev->info->event_attrs->attrs;
	407	while (*attr++ != NULL)
	408	attrcount_orig++;
	409	}
	410	attrcount = attrcount_orig;
	411	if (indio_dev->channels) {
	412	ret = __iio_add_event_config_attrs(indio_dev);
	413	if (ret < 0)
	414	goto error_free_setup_event_lines;
	415	attrcount += ret;
	416	}
	417
	418	indio_dev->event_interface->group.name = iio_event_group_name;
	419	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
	420	sizeof(indio_dev->event_interface->group.attrs[0]),
	421	GFP_KERNEL);
	422	if (indio_dev->event_interface->group.attrs == NULL) {
	423	ret = -ENOMEM;
	424	goto error_free_setup_event_lines;
	425	}
	426	if (indio_dev->info->event_attrs)
	427	memcpy(indio_dev->event_interface->group.attrs,
	428	indio_dev->info->event_attrs->attrs,
	429	sizeof(indio_dev->event_interface->group.attrs[0])
	430	*attrcount_orig);
	431	attrn = attrcount_orig;
	432	/* Add all elements from the list. */
	433	list_for_each_entry(p,
	434	&indio_dev->event_interface->dev_attr_list,
	435	l)
	436	indio_dev->event_interface->group.attrs[attrn++] =
	437	&p->dev_attr.attr;
	438	indio_dev->groups[indio_dev->groupcounter++] =
	439	&indio_dev->event_interface->group;
	440
	441	return 0;
	442
	443	error_free_setup_event_lines:
	444	__iio_remove_event_config_attrs(indio_dev);
	445	kfree(indio_dev->event_interface);
	446	error_ret:
	447
	448	return ret;
	449	}
	450
	451	void iio_device_unregister_eventset(struct iio_dev *indio_dev)
	452	{
	453	if (indio_dev->event_interface == NULL)
	454	return;
	455	__iio_remove_event_config_attrs(indio_dev);
	456	kfree(indio_dev->event_interface->group.attrs);
	457	kfree(indio_dev->event_interface);
	458	}