[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;

	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;

	if (indio_dev->info->write_event_config)
		ret = indio_dev->info->write_event_config(indio_dev,
			this_attr->address, val);
	else
		ret = indio_dev->info->write_event_config_new(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;

	if (indio_dev->info->read_event_config)
		val = indio_dev->info->read_event_config(indio_dev,
			this_attr->address);
	else
		val = indio_dev->info->read_event_config_new(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;

	if (indio_dev->info->read_event_value) {
		ret = indio_dev->info->read_event_value(indio_dev,
			this_attr->address, &val);
		if (ret < 0)
			return ret;
		return sprintf(buf, "%d\n", val);
	} else {
		ret = indio_dev->info->read_event_value_new(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 &&
		!indio_dev->info->write_event_value_new)
		return -EINVAL;

	if (indio_dev->info->write_event_value) {
		ret = kstrtoint(buf, 10, &val);
		if (ret)
			return ret;
		ret = indio_dev->info->write_event_value(indio_dev,
			this_attr->address, val);
	} else {
		ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
		if (ret)
			return ret;
		ret = indio_dev->info->write_event_value_new(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_new(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)
			goto error_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)
			goto error_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)
			goto error_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)
			goto error_ret;
		attrcount += ret;
	}
	ret = attrcount;
error_ret:
	return ret;
}

static int iio_device_add_event_sysfs_old(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 int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
				      struct iio_chan_spec const *chan)
{
	if (chan->event_mask)
		return iio_device_add_event_sysfs_old(indio_dev, chan);
	else
		return iio_device_add_event_sysfs_new(indio_dev, chan);
}

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;
		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) {
		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_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
	kfree(indio_dev->event_interface);
error_ret:

	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
	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;
e18045ed LPC	78
f18e7a06 LPC	79	if (!indio_dev->info)
	80	return -ENODEV;
	81
e18045ed LPC	82	poll_wait(filep, &ev_int->wait, wait);
e18045ed LPC	83
1b9dc91e	84	spin_lock_irq(&ev_int->wait.lock);
e18045ed LPC	85	if (!kfifo_is_empty(&ev_int->det_events))
e18045ed LPC	86	events = POLLIN \| POLLRDNORM;
1b9dc91e	87	spin_unlock_irq(&ev_int->wait.lock);
e18045ed LPC	88
	89	return events;
	90	}
	91
0a769a95 LPC	92	static ssize_t iio_event_chrdev_read(struct file *filep,
	93	char __user *buf,
	94	size_t count,
	95	loff_t *f_ps)
	96	{
cadc2125 LPC	97	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	98	struct iio_event_interface *ev_int = indio_dev->event_interface;
2c00193f	99	unsigned int copied;
0a769a95 LPC	100	int ret;
0a769a95 LPC	101
f18e7a06 LPC	102	if (!indio_dev->info)
	103	return -ENODEV;
	104
2c00193f	105	if (count < sizeof(struct iio_event_data))
0a769a95 LPC	106	return -EINVAL;
0a769a95 LPC	107
1b9dc91e	108	spin_lock_irq(&ev_int->wait.lock);
2c00193f	109	if (kfifo_is_empty(&ev_int->det_events)) {
0a769a95 LPC	110	if (filep->f_flags & O_NONBLOCK) {
0a769a95 LPC	111	ret = -EAGAIN;
43ba1100	112	goto error_unlock;
0a769a95	113	}
0a769a95	114	/* Blocking on device; waiting for something to be there */
1b9dc91e	115	ret = wait_event_interruptible_locked_irq(ev_int->wait,
d2f0a48f LPC	116	!kfifo_is_empty(&ev_int->det_events) \|\|
d2f0a48f LPC	117	indio_dev->info == NULL);
0a769a95	118	if (ret)
43ba1100	119	goto error_unlock;
d2f0a48f LPC	120	if (indio_dev->info == NULL) {
	121	ret = -ENODEV;
	122	goto error_unlock;
	123	}
0a769a95	124	/* Single access device so no one else can get the data */
0a769a95 LPC	125	}
0a769a95 LPC	126
2c00193f	127	ret = kfifo_to_user(&ev_int->det_events, buf, count, &copied);
0a769a95	128
43ba1100	129	error_unlock:
1b9dc91e	130	spin_unlock_irq(&ev_int->wait.lock);
43ba1100	131
2c00193f	132	return ret ? ret : copied;
0a769a95 LPC	133	}
	134
	135	static int iio_event_chrdev_release(struct inode inode, struct file filep)
	136	{
cadc2125 LPC	137	struct iio_dev *indio_dev = filep->private_data;
cadc2125 LPC	138	struct iio_event_interface *ev_int = indio_dev->event_interface;
0a769a95	139
1b9dc91e	140	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	141	__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
0a769a95 LPC	142	/*
	143	* In order to maintain a clean state for reopening,
	144	* clear out any awaiting events. The mask will prevent
	145	* any new __iio_push_event calls running.
	146	*/
2c00193f	147	kfifo_reset_out(&ev_int->det_events);
1b9dc91e	148	spin_unlock_irq(&ev_int->wait.lock);
0a769a95	149
cadc2125 LPC	150	iio_device_put(indio_dev);
cadc2125 LPC	151
0a769a95 LPC	152	return 0;
	153	}
	154
	155	static const struct file_operations iio_event_chrdev_fileops = {
	156	.read = iio_event_chrdev_read,
e18045ed	157	.poll = iio_event_poll,
0a769a95 LPC	158	.release = iio_event_chrdev_release,
	159	.owner = THIS_MODULE,
	160	.llseek = noop_llseek,
	161	};
	162
	163	int iio_event_getfd(struct iio_dev *indio_dev)
	164	{
	165	struct iio_event_interface *ev_int = indio_dev->event_interface;
	166	int fd;
	167
	168	if (ev_int == NULL)
	169	return -ENODEV;
	170
1b9dc91e	171	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	172	if (__test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) {
1b9dc91e	173	spin_unlock_irq(&ev_int->wait.lock);
0a769a95 LPC	174	return -EBUSY;
0a769a95 LPC	175	}
1b9dc91e	176	spin_unlock_irq(&ev_int->wait.lock);
cadc2125 LPC	177	iio_device_get(indio_dev);
	178
	179	fd = anon_inode_getfd("iio:event", &iio_event_chrdev_fileops,
e2aad1d5	180	indio_dev, O_RDONLY \| O_CLOEXEC);
0a769a95	181	if (fd < 0) {
1b9dc91e	182	spin_lock_irq(&ev_int->wait.lock);
a046c1e8	183	__clear_bit(IIO_BUSY_BIT_POS, &ev_int->flags);
1b9dc91e	184	spin_unlock_irq(&ev_int->wait.lock);
cadc2125	185	iio_device_put(indio_dev);
0a769a95 LPC	186	}
	187	return fd;
	188	}
	189
	190	static const char * const iio_ev_type_text[] = {
	191	[IIO_EV_TYPE_THRESH] = "thresh",
	192	[IIO_EV_TYPE_MAG] = "mag",
	193	[IIO_EV_TYPE_ROC] = "roc",
	194	[IIO_EV_TYPE_THRESH_ADAPTIVE] = "thresh_adaptive",
	195	[IIO_EV_TYPE_MAG_ADAPTIVE] = "mag_adaptive",
	196	};
	197
	198	static const char * const iio_ev_dir_text[] = {
	199	[IIO_EV_DIR_EITHER] = "either",
	200	[IIO_EV_DIR_RISING] = "rising",
	201	[IIO_EV_DIR_FALLING] = "falling"
	202	};
	203
b4e3ac0a LPC	204	static const char * const iio_ev_info_text[] = {
	205	[IIO_EV_INFO_ENABLE] = "en",
	206	[IIO_EV_INFO_VALUE] = "value",
ec6670ae	207	[IIO_EV_INFO_HYSTERESIS] = "hysteresis",
b4e3ac0a LPC	208	};
	209
	210	static enum iio_event_direction iio_ev_attr_dir(struct iio_dev_attr *attr)
	211	{
	212	return attr->c->event_spec[attr->address & 0xffff].dir;
	213	}
	214
	215	static enum iio_event_type iio_ev_attr_type(struct iio_dev_attr *attr)
	216	{
	217	return attr->c->event_spec[attr->address & 0xffff].type;
	218	}
	219
	220	static enum iio_event_info iio_ev_attr_info(struct iio_dev_attr *attr)
	221	{
	222	return (attr->address >> 16) & 0xffff;
	223	}
	224
0a769a95 LPC	225	static ssize_t iio_ev_state_store(struct device *dev,
	226	struct device_attribute *attr,
	227	const char *buf,
	228	size_t len)
	229	{
e53f5ac5	230	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95 LPC	231	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
	232	int ret;
	233	bool val;
	234
	235	ret = strtobool(buf, &val);
	236	if (ret < 0)
	237	return ret;
	238
b4e3ac0a LPC	239	if (indio_dev->info->write_event_config)
	240	ret = indio_dev->info->write_event_config(indio_dev,
	241	this_attr->address, val);
	242	else
	243	ret = indio_dev->info->write_event_config_new(indio_dev,
	244	this_attr->c, iio_ev_attr_type(this_attr),
	245	iio_ev_attr_dir(this_attr), val);
	246
0a769a95 LPC	247	return (ret < 0) ? ret : len;
	248	}
	249
	250	static ssize_t iio_ev_state_show(struct device *dev,
	251	struct device_attribute *attr,
	252	char *buf)
	253	{
e53f5ac5	254	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	255	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	256	int val;
0a769a95	257
b4e3ac0a LPC	258	if (indio_dev->info->read_event_config)
	259	val = indio_dev->info->read_event_config(indio_dev,
	260	this_attr->address);
	261	else
	262	val = indio_dev->info->read_event_config_new(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);
b4e3ac0a LPC	277	int val, val2;
b4e3ac0a LPC	278	int ret;
0a769a95	279
b4e3ac0a LPC	280	if (indio_dev->info->read_event_value) {
	281	ret = indio_dev->info->read_event_value(indio_dev,
	282	this_attr->address, &val);
	283	if (ret < 0)
	284	return ret;
	285	return sprintf(buf, "%d\n", val);
	286	} else {
	287	ret = indio_dev->info->read_event_value_new(indio_dev,
	288	this_attr->c, iio_ev_attr_type(this_attr),
	289	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	290	&val, &val2);
	291	if (ret < 0)
	292	return ret;
	293	return iio_format_value(buf, ret, val, val2);
	294	}
0a769a95 LPC	295	}
	296
	297	static ssize_t iio_ev_value_store(struct device *dev,
	298	struct device_attribute *attr,
	299	const char *buf,
	300	size_t len)
	301	{
e53f5ac5	302	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
0a769a95	303	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
b4e3ac0a	304	int val, val2;
0a769a95 LPC	305	int ret;
0a769a95 LPC	306
b4e3ac0a LPC	307	if (!indio_dev->info->write_event_value &&
b4e3ac0a LPC	308	!indio_dev->info->write_event_value_new)
0a769a95 LPC	309	return -EINVAL;
0a769a95 LPC	310
b4e3ac0a LPC	311	if (indio_dev->info->write_event_value) {
	312	ret = kstrtoint(buf, 10, &val);
	313	if (ret)
	314	return ret;
	315	ret = indio_dev->info->write_event_value(indio_dev,
	316	this_attr->address, val);
	317	} else {
	318	ret = iio_str_to_fixpoint(buf, 100000, &val, &val2);
	319	if (ret)
	320	return ret;
	321	ret = indio_dev->info->write_event_value_new(indio_dev,
	322	this_attr->c, iio_ev_attr_type(this_attr),
	323	iio_ev_attr_dir(this_attr), iio_ev_attr_info(this_attr),
	324	val, val2);
	325	}
0a769a95 LPC	326	if (ret < 0)
	327	return ret;
	328
	329	return len;
	330	}
	331
b4e3ac0a LPC	332	static int iio_device_add_event(struct iio_dev *indio_dev,
	333	const struct iio_chan_spec *chan, unsigned int spec_index,
	334	enum iio_event_type type, enum iio_event_direction dir,
	335	enum iio_shared_by shared_by, const unsigned long *mask)
	336	{
	337	ssize_t (show)(struct device , struct device_attribute , char );
	338	ssize_t (store)(struct device , struct device_attribute *,
	339	const char *, size_t);
	340	unsigned int attrcount = 0;
	341	unsigned int i;
	342	char *postfix;
	343	int ret;
	344
	345	for_each_set_bit(i, mask, sizeof(*mask)) {
	346	postfix = kasprintf(GFP_KERNEL, "%s_%s_%s",
	347	iio_ev_type_text[type], iio_ev_dir_text[dir],
	348	iio_ev_info_text[i]);
	349	if (postfix == NULL)
	350	return -ENOMEM;
	351
	352	if (i == IIO_EV_INFO_ENABLE) {
	353	show = iio_ev_state_show;
	354	store = iio_ev_state_store;
	355	} else {
	356	show = iio_ev_value_show;
	357	store = iio_ev_value_store;
	358	}
	359
	360	ret = __iio_add_chan_devattr(postfix, chan, show, store,
	361	(i << 16) \| spec_index, shared_by, &indio_dev->dev,
	362	&indio_dev->event_interface->dev_attr_list);
	363	kfree(postfix);
	364
	365	if (ret)
	366	return ret;
	367
	368	attrcount++;
	369	}
	370
	371	return attrcount;
	372	}
	373
	374	static int iio_device_add_event_sysfs_new(struct iio_dev *indio_dev,
	375	struct iio_chan_spec const *chan)
	376	{
	377	int ret = 0, i, attrcount = 0;
	378	enum iio_event_direction dir;
	379	enum iio_event_type type;
	380
	381	for (i = 0; i < chan->num_event_specs; i++) {
	382	type = chan->event_spec[i].type;
	383	dir = chan->event_spec[i].dir;
	384
	385	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	386	IIO_SEPARATE, &chan->event_spec[i].mask_separate);
	387	if (ret < 0)
	388	goto error_ret;
	389	attrcount += ret;
	390
	391	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
	392	IIO_SHARED_BY_TYPE,
	393	&chan->event_spec[i].mask_shared_by_type);
	394	if (ret < 0)
	395	goto error_ret;
396	attrcount += ret;
397
398	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
399	IIO_SHARED_BY_DIR,
400	&chan->event_spec[i].mask_shared_by_dir);
401	if (ret < 0)
402	goto error_ret;
403	attrcount += ret;
404
405	ret = iio_device_add_event(indio_dev, chan, i, type, dir,
406	IIO_SHARED_BY_ALL,
407	&chan->event_spec[i].mask_shared_by_all);
408	if (ret < 0)
409	goto error_ret;
410	attrcount += ret;
411	}
412	ret = attrcount;
413	error_ret:
414	return ret;
415	}
416
417	static int iio_device_add_event_sysfs_old(struct iio_dev *indio_dev,
0a769a95 LPC	418	struct iio_chan_spec const *chan)
	419	{
	420	int ret = 0, i, attrcount = 0;
	421	u64 mask = 0;
	422	char *postfix;
	423	if (!chan->event_mask)
	424	return 0;
	425
	426	for_each_set_bit(i, &chan->event_mask, sizeof(chan->event_mask)*8) {
	427	postfix = kasprintf(GFP_KERNEL, "%s_%s_en",
	428	iio_ev_type_text[i/IIO_EV_DIR_MAX],
	429	iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
	430	if (postfix == NULL) {
	431	ret = -ENOMEM;
	432	goto error_ret;
	433	}
	434	if (chan->modified)
2b0774df	435	mask = IIO_MOD_EVENT_CODE(chan->type, 0, chan->channel2,
0a769a95 LPC	436	i/IIO_EV_DIR_MAX,
	437	i%IIO_EV_DIR_MAX);
	438	else if (chan->differential)
	439	mask = IIO_EVENT_CODE(chan->type,
	440	0, 0,
	441	i%IIO_EV_DIR_MAX,
	442	i/IIO_EV_DIR_MAX,
	443	0,
	444	chan->channel,
	445	chan->channel2);
	446	else
	447	mask = IIO_UNMOD_EVENT_CODE(chan->type,
	448	chan->channel,
	449	i/IIO_EV_DIR_MAX,
	450	i%IIO_EV_DIR_MAX);
	451
	452	ret = __iio_add_chan_devattr(postfix,
	453	chan,
	454	&iio_ev_state_show,
	455	iio_ev_state_store,
	456	mask,
	457	0,
	458	&indio_dev->dev,
	459	&indio_dev->event_interface->
	460	dev_attr_list);
	461	kfree(postfix);
	462	if (ret)
	463	goto error_ret;
	464	attrcount++;
	465	postfix = kasprintf(GFP_KERNEL, "%s_%s_value",
	466	iio_ev_type_text[i/IIO_EV_DIR_MAX],
	467	iio_ev_dir_text[i%IIO_EV_DIR_MAX]);
	468	if (postfix == NULL) {
	469	ret = -ENOMEM;
	470	goto error_ret;
	471	}
	472	ret = __iio_add_chan_devattr(postfix, chan,
	473	iio_ev_value_show,
	474	iio_ev_value_store,
	475	mask,
	476	0,
	477	&indio_dev->dev,
	478	&indio_dev->event_interface->
	479	dev_attr_list);
	480	kfree(postfix);
	481	if (ret)
	482	goto error_ret;
	483	attrcount++;
	484	}
	485	ret = attrcount;
	486	error_ret:
	487	return ret;
	488	}
	489
b4e3ac0a LPC	490
	491	static int iio_device_add_event_sysfs(struct iio_dev *indio_dev,
	492	struct iio_chan_spec const *chan)
	493	{
	494	if (chan->event_mask)
	495	return iio_device_add_event_sysfs_old(indio_dev, chan);
	496	else
	497	return iio_device_add_event_sysfs_new(indio_dev, chan);
	498	}
	499
0a769a95 LPC	500	static inline int __iio_add_event_config_attrs(struct iio_dev *indio_dev)
	501	{
	502	int j, ret, attrcount = 0;
	503
0a769a95 LPC	504	/* Dynically created from the channels array */
	505	for (j = 0; j < indio_dev->num_channels; j++) {
	506	ret = iio_device_add_event_sysfs(indio_dev,
	507	&indio_dev->channels[j]);
	508	if (ret < 0)
e3db9ef6	509	return ret;
0a769a95 LPC	510	attrcount += ret;
	511	}
	512	return attrcount;
0a769a95 LPC	513	}
	514
	515	static bool iio_check_for_dynamic_events(struct iio_dev *indio_dev)
	516	{
	517	int j;
	518
b4e3ac0a	519	for (j = 0; j < indio_dev->num_channels; j++) {
0a769a95 LPC	520	if (indio_dev->channels[j].event_mask != 0)
0a769a95 LPC	521	return true;
b4e3ac0a LPC	522	if (indio_dev->channels[j].num_event_specs != 0)
	523	return true;
	524	}
0a769a95 LPC	525	return false;
	526	}
	527
	528	static void iio_setup_ev_int(struct iio_event_interface *ev_int)
	529	{
2c00193f	530	INIT_KFIFO(ev_int->det_events);
0a769a95 LPC	531	init_waitqueue_head(&ev_int->wait);
	532	}
	533
	534	static const char *iio_event_group_name = "events";
	535	int iio_device_register_eventset(struct iio_dev *indio_dev)
	536	{
	537	struct iio_dev_attr *p;
	538	int ret = 0, attrcount_orig = 0, attrcount, attrn;
	539	struct attribute **attr;
	540
	541	if (!(indio_dev->info->event_attrs \|\|
	542	iio_check_for_dynamic_events(indio_dev)))
	543	return 0;
	544
	545	indio_dev->event_interface =
	546	kzalloc(sizeof(struct iio_event_interface), GFP_KERNEL);
	547	if (indio_dev->event_interface == NULL) {
	548	ret = -ENOMEM;
	549	goto error_ret;
	550	}
	551
46b24311 SH	552	INIT_LIST_HEAD(&indio_dev->event_interface->dev_attr_list);
46b24311 SH	553
0a769a95 LPC	554	iio_setup_ev_int(indio_dev->event_interface);
	555	if (indio_dev->info->event_attrs != NULL) {
	556	attr = indio_dev->info->event_attrs->attrs;
	557	while (*attr++ != NULL)
	558	attrcount_orig++;
	559	}
	560	attrcount = attrcount_orig;
	561	if (indio_dev->channels) {
	562	ret = __iio_add_event_config_attrs(indio_dev);
	563	if (ret < 0)
	564	goto error_free_setup_event_lines;
	565	attrcount += ret;
	566	}
	567
	568	indio_dev->event_interface->group.name = iio_event_group_name;
	569	indio_dev->event_interface->group.attrs = kcalloc(attrcount + 1,
	570	sizeof(indio_dev->event_interface->group.attrs[0]),
	571	GFP_KERNEL);
	572	if (indio_dev->event_interface->group.attrs == NULL) {
	573	ret = -ENOMEM;
	574	goto error_free_setup_event_lines;
	575	}
	576	if (indio_dev->info->event_attrs)
	577	memcpy(indio_dev->event_interface->group.attrs,
	578	indio_dev->info->event_attrs->attrs,
	579	sizeof(indio_dev->event_interface->group.attrs[0])
	580	*attrcount_orig);
	581	attrn = attrcount_orig;
	582	/* Add all elements from the list. */
	583	list_for_each_entry(p,
	584	&indio_dev->event_interface->dev_attr_list,
	585	l)
	586	indio_dev->event_interface->group.attrs[attrn++] =
	587	&p->dev_attr.attr;
	588	indio_dev->groups[indio_dev->groupcounter++] =
	589	&indio_dev->event_interface->group;
	590
	591	return 0;
	592
	593	error_free_setup_event_lines:
84088ebd	594	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95 LPC	595	kfree(indio_dev->event_interface);
	596	error_ret:
	597
	598	return ret;
	599	}
	600
d2f0a48f LPC	601	/**
	602	* iio_device_wakeup_eventset - Wakes up the event waitqueue
	603	* @indio_dev: The IIO device
	604	*
	605	* Wakes up the event waitqueue used for poll() and blocking read().
	606	* Should usually be called when the device is unregistered.
	607	*/
	608	void iio_device_wakeup_eventset(struct iio_dev *indio_dev)
	609	{
	610	if (indio_dev->event_interface == NULL)
	611	return;
	612	wake_up(&indio_dev->event_interface->wait);
	613	}
	614
0a769a95 LPC	615	void iio_device_unregister_eventset(struct iio_dev *indio_dev)
	616	{
	617	if (indio_dev->event_interface == NULL)
	618	return;
84088ebd	619	iio_free_chan_devattr_list(&indio_dev->event_interface->dev_attr_list);
0a769a95 LPC	620	kfree(indio_dev->event_interface->group.attrs);
	621	kfree(indio_dev->event_interface);
	622	}