[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / staging / iio / iio.h

/* The industrial I/O core
 *
 * 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.
 */

#ifndef _INDUSTRIAL_IO_H_
#define _INDUSTRIAL_IO_H_

#include <linux/device.h>
#include <linux/cdev.h>
#include "sysfs.h"
#include "chrdev.h"

/* IIO TODO LIST */
/* Static device specific elements (conversion factors etc)
 * should be exported via sysfs
 *
 * Provide means of adjusting timer accuracy.
 * Currently assumes nano seconds.
 */

/* Event interface flags */
#define IIO_BUSY_BIT_POS 1

struct iio_dev;

/**
 * iio_get_time_ns() - utility function to get a time stamp for events etc
 **/
static inline s64 iio_get_time_ns(void)
{
	struct timespec ts;
	/*
	 * calls getnstimeofday.
	 * If hrtimers then up to ns accurate, if not microsecond.
	 */
	ktime_get_real_ts(&ts);

	return timespec_to_ns(&ts);
}

/**
 * iio_add_event_to_list() - Wraps adding to event lists
 * @el:		the list element of the event to be handled.
 * @head:	the list associated with the event handler being used.
 *
 * Does reference counting to allow shared handlers.
 **/
void iio_add_event_to_list(struct iio_event_handler_list *el,
			   struct list_head *head);

/**
 * iio_remove_event_from_list() - Wraps removing from event list
 * @el:		element to be removed
 * @head:	associate list head for the interrupt handler.
 *
 * Does reference counting to allow shared handlers.
 **/
void iio_remove_event_from_list(struct iio_event_handler_list *el,
				struct list_head *head);

/* Device operating modes */
#define INDIO_DIRECT_MODE		0x01
#define INDIO_RING_TRIGGERED		0x02
#define INDIO_RING_HARDWARE_BUFFER	0x08

#define INDIO_ALL_RING_MODES (INDIO_RING_TRIGGERED | INDIO_RING_HARDWARE_BUFFER)

/* Vast majority of this is set by the industrialio subsystem on a
 * call to iio_device_register. */

/**
 * struct iio_dev - industrial I/O device
 * @id:			[INTERN] used to identify device internally
 * @dev_data:		[DRIVER] device specific data
 * @modes:		[DRIVER] operating modes supported by device
 * @currentmode:	[DRIVER] current operating mode
 * @dev:		[DRIVER] device structure, should be assigned a parent
 *			and owner
 * @attrs:		[DRIVER] general purpose device attributes
 * @driver_module:	[DRIVER] module structure used to ensure correct
 *			ownership of chrdevs etc
 * @num_interrupt_lines:[DRIVER] number of physical interrupt lines from device
 * @interrupts:		[INTERN] interrupt line specific event lists etc
 * @event_attrs:	[DRIVER] event control attributes
 * @event_conf_attrs:	[DRIVER] event configuration attributes
 * @event_interfaces:	[INTERN] event chrdevs associated with interrupt lines
 * @ring:		[DRIVER] any ring buffer present
 * @mlock:		[INTERN] lock used to prevent simultaneous device state
 *			changes
 * @scan_el_attrs:	[DRIVER] control of scan elements if that scan mode
 *			control method is used
 * @scan_count:	[INTERN] the number of elements in the current scan mode
 * @scan_mask:		[INTERN] bitmask used in masking scan mode elements
 * @scan_timestamp:	[INTERN] does the scan mode include a timestamp
 * @trig:		[INTERN] current device trigger (ring buffer modes)
 * @pollfunc:		[DRIVER] function run on trigger being recieved
 **/
struct iio_dev {
	int				id;
	void				*dev_data;
	int				modes;
	int				currentmode;
	struct device			dev;
	const struct attribute_group	*attrs;
	struct module			*driver_module;

	int				num_interrupt_lines;
	struct iio_interrupt		**interrupts;
	struct attribute_group		*event_attrs;
	struct attribute_group		*event_conf_attrs;

	struct iio_event_interface	*event_interfaces;

	struct iio_ring_buffer		*ring;
	struct mutex			mlock;

	struct attribute_group		*scan_el_attrs;
	int				scan_count;

	u16				scan_mask;
	bool				scan_timestamp;
	struct iio_trigger		*trig;
	struct iio_poll_func		*pollfunc;
};

/*
 * These are mainly provided to allow for a change of implementation if a device
 * has a large number of scan elements
 */
#define IIO_MAX_SCAN_LENGTH 15

static inline int iio_scan_mask_query(struct iio_dev *dev_info, int bit)
{
	if (bit > IIO_MAX_SCAN_LENGTH)
		return -EINVAL;
	else
		return !!(dev_info->scan_mask & (1 << bit));
};

static inline int iio_scan_mask_set(struct iio_dev *dev_info, int bit)
{
	if (bit > IIO_MAX_SCAN_LENGTH)
		return -EINVAL;
	dev_info->scan_mask |= (1 << bit);
	dev_info->scan_count++;
	return 0;
};

static inline int iio_scan_mask_clear(struct iio_dev *dev_info, int bit)
{
	if (bit > IIO_MAX_SCAN_LENGTH)
		return -EINVAL;
	dev_info->scan_mask &= ~(1 << bit);
	dev_info->scan_count--;
	return 0;
};

/**
 * iio_scan_mask_count_to_right() - how many scan elements occur before here
 * @dev_info: the iio_device whose scan mode we are querying
 * @bit: which number scan element is this
 **/
static inline int iio_scan_mask_count_to_right(struct iio_dev *dev_info,
						int bit)
{
	int count = 0;
	int mask = (1 << bit);
	if (bit > IIO_MAX_SCAN_LENGTH)
		return -EINVAL;
	while (mask) {
		mask >>= 1;
		if (mask & dev_info->scan_mask)
			count++;
	}

	return count;
}

/**
 * iio_device_register() - register a device with the IIO subsystem
 * @dev_info:		Device structure filled by the device driver
 **/
int iio_device_register(struct iio_dev *dev_info);

/**
 * iio_device_unregister() - unregister a device from the IIO subsystem
 * @dev_info:		Device structure representing the device.
 **/
void iio_device_unregister(struct iio_dev *dev_info);

/**
 * struct iio_interrupt - wrapper used to allow easy handling of multiple
 *			physical interrupt lines
 * @dev_info:		the iio device for which the is an interrupt line
 * @line_number:	associated line number
 * @id:			idr allocated unique id number
 * @irq:		associate interrupt number
 * @ev_list:		event handler list for associated events
 * @ev_list_lock:	ensure only one access to list at a time
 **/
struct iio_interrupt {
	struct iio_dev			*dev_info;
	int				line_number;
	int				id;
	int				irq;
	struct list_head		ev_list;
	spinlock_t			ev_list_lock;
};

#define to_iio_interrupt(i) container_of(i, struct iio_interrupt, ev_list)

/**
 * iio_register_interrupt_line() - Tell IIO about interrupt lines
 *
 * @irq:		Typically provided via platform data
 * @dev_info:		IIO device info structure for device
 * @line_number:	Which interrupt line of the device is this?
 * @type:		Interrupt type (e.g. edge triggered etc)
 * @name:		Identifying name.
 **/
int iio_register_interrupt_line(unsigned int			irq,
				struct iio_dev			*dev_info,
				int				line_number,
				unsigned long			type,
				const char			*name);

void iio_unregister_interrupt_line(struct iio_dev *dev_info,
				   int line_number);


/**
 * iio_push_event() - try to add event to the list for userspace reading
 * @dev_info:		IIO device structure
 * @ev_line:		Which event line (hardware interrupt)
 * @ev_code:		What event
 * @timestamp:		When the event occurred
 **/
int iio_push_event(struct iio_dev *dev_info,
		  int ev_line,
		  int ev_code,
		  s64 timestamp);

/**
 * struct iio_work_cont - container for when singleton handler case matters
 * @ws:			[DEVICE] work_struct when not only possible event
 * @ws_nocheck:		[DEVICE] work_struct when only possible event
 * @address:		[DEVICE] associated register address
 * @mask:		[DEVICE] associated mask for identifying event source
 * @st:			[DEVICE] device specific state information
 **/
struct iio_work_cont {
	struct work_struct	ws;
	struct work_struct	ws_nocheck;
	int			address;
	int			mask;
	void			*st;
};

#define to_iio_work_cont_check(_ws)			\
	container_of(_ws, struct iio_work_cont, ws)

#define to_iio_work_cont_no_check(_ws)				\
	container_of(_ws, struct iio_work_cont, ws_nocheck)

/**
 * iio_init_work_cont() - intiialize the elements of a work container
 * @cont: the work container
 * @_checkfunc: function called when there are multiple possible int sources
 * @_nocheckfunc: function for when there is only one int source
 * @_add: driver dependent, typically a register address
 * @_mask: driver dependent, typically a bit mask for a register
 * @_st: driver dependent, typically pointer to a device state structure
 **/
static inline void
iio_init_work_cont(struct iio_work_cont *cont,
		   void (*_checkfunc)(struct work_struct *),
		   void (*_nocheckfunc)(struct work_struct *),
		   int _add, int _mask, void *_st)
{
	INIT_WORK(&(cont)->ws, _checkfunc);
	INIT_WORK(&(cont)->ws_nocheck, _nocheckfunc);
	cont->address = _add;
	cont->mask = _mask;
	cont->st = _st;
}
/**
 * __iio_push_event() - tries to add an event to the list associated with a chrdev
 * @ev_int:		the event interface to which we are pushing the event
 * @ev_code:		the outgoing event code
 * @timestamp:		timestamp of the event
 * @shared_pointer_p:	the shared event pointer
 **/
int __iio_push_event(struct iio_event_interface *ev_int,
		    int ev_code,
		    s64 timestamp,
		    struct iio_shared_ev_pointer*
		    shared_pointer_p);
/**
 * __iio_change_event() - change an event code in case of event escalation
 * @ev:			the event to be changed
 * @ev_code:		new event code
 * @timestamp:		new timestamp
 **/
void __iio_change_event(struct iio_detected_event_list *ev,
			int ev_code,
			s64 timestamp);

/**
 * iio_setup_ev_int() - configure an event interface (chrdev)
 * @name:		name used for resulting sysfs directory etc.
 * @ev_int:		interface we are configuring
 * @owner:		module that is responsible for registering this ev_int
 * @dev:		device whose ev_int this is
 **/
int iio_setup_ev_int(struct iio_event_interface *ev_int,
		     const char *name,
		     struct module *owner,
		     struct device *dev);

void iio_free_ev_int(struct iio_event_interface *ev_int);

/**
 * iio_allocate_chrdev() - Allocate a chrdev
 * @handler:	struct that contains relevant file handling for chrdev
 * @dev_info:	iio_dev for which chrdev is being created
 **/
int iio_allocate_chrdev(struct iio_handler *handler, struct iio_dev *dev_info);
void iio_deallocate_chrdev(struct iio_handler *handler);

/* Used to distinguish between bipolar and unipolar scan elemenents.
 * Whilst this may seem obvious, we may well want to change the representation
 * in the future!*/
#define IIO_SIGNED(a) -(a)
#define IIO_UNSIGNED(a) (a)

extern dev_t iio_devt;
extern struct class iio_class;

/**
 * iio_put_device() - reference counted deallocation of struct device
 * @dev: the iio_device containing the device
 **/
static inline void iio_put_device(struct iio_dev *dev)
{
	if (dev)
		put_device(&dev->dev);
};

/**
 * to_iio_dev() - get iio_dev for which we have the struct device
 * @d: the struct device
 **/
static inline struct iio_dev *to_iio_dev(struct device *d)
{
	return container_of(d, struct iio_dev, dev);
};

/**
 * iio_dev_get_devdata() - helper function gets device specific data
 * @d: the iio_dev associated with the device
 **/
static inline void *iio_dev_get_devdata(struct iio_dev *d)
{
	return d->dev_data;
}

/**
 * iio_allocate_device() - allocate an iio_dev from a driver
 **/
struct iio_dev *iio_allocate_device(void);

/**
 * iio_free_device() - free an iio_dev from a driver
 * @dev: the iio_dev associated with the device
 **/
void iio_free_device(struct iio_dev *dev);

/**
 * iio_put() - internal module reference count reduce
 **/
void iio_put(void);

/**
 * iio_get() - internal module reference count increase
 **/
void iio_get(void);

/* Ring buffer related */
int iio_device_get_chrdev_minor(void);
void iio_device_free_chrdev_minor(int val);

/**
 * iio_ring_enabled() - helper function to test if any form of ring is enabled
 * @dev_info:		IIO device info structure for device
 **/
static inline bool iio_ring_enabled(struct iio_dev *dev_info)
{
	return dev_info->currentmode
		& (INDIO_RING_TRIGGERED
		   | INDIO_RING_HARDWARE_BUFFER);
};

struct idr;

int iio_get_new_idr_val(struct idr *this_idr);
void iio_free_idr_val(struct idr *this_idr, int id);
#endif /* _INDUSTRIAL_IO_H_ */
Commit	Line	Data
847ec80b JC	1	/* The industrial I/O core
	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
	10	#ifndef _INDUSTRIAL_IO_H_
	11	#define _INDUSTRIAL_IO_H_
	12
	13	#include <linux/device.h>
	14	#include <linux/cdev.h>
	15	#include "sysfs.h"
	16	#include "chrdev.h"
	17
	18	/* IIO TODO LIST */
	19	/* Static device specific elements (conversion factors etc)
	20	* should be exported via sysfs
	21	*
	22	* Provide means of adjusting timer accuracy.
	23	* Currently assumes nano seconds.
	24	*/
	25
	26	/* Event interface flags */
	27	#define IIO_BUSY_BIT_POS 1
	28
	29	struct iio_dev;
	30
	31	/**
	32	* iio_get_time_ns() - utility function to get a time stamp for events etc
	33	**/
	34	static inline s64 iio_get_time_ns(void)
	35	{
	36	struct timespec ts;
	37	/*
	38	* calls getnstimeofday.
	39	* If hrtimers then up to ns accurate, if not microsecond.
	40	*/
	41	ktime_get_real_ts(&ts);
	42
	43	return timespec_to_ns(&ts);
	44	}
	45
	46	/**
	47	* iio_add_event_to_list() - Wraps adding to event lists
	48	* @el: the list element of the event to be handled.
	49	* @head: the list associated with the event handler being used.
	50	*
	51	* Does reference counting to allow shared handlers.
	52	**/
	53	void iio_add_event_to_list(struct iio_event_handler_list *el,
	54	struct list_head *head);
	55
	56	/**
	57	* iio_remove_event_from_list() - Wraps removing from event list
	58	* @el: element to be removed
	59	* @head: associate list head for the interrupt handler.
	60	*
	61	* Does reference counting to allow shared handlers.
	62	**/
	63	void iio_remove_event_from_list(struct iio_event_handler_list *el,
	64	struct list_head *head);
65
66	/* Device operating modes */
67	#define INDIO_DIRECT_MODE 0x01
68	#define INDIO_RING_TRIGGERED 0x02
69	#define INDIO_RING_HARDWARE_BUFFER 0x08
70
71	#define INDIO_ALL_RING_MODES (INDIO_RING_TRIGGERED \| INDIO_RING_HARDWARE_BUFFER)
72
73	/* Vast majority of this is set by the industrialio subsystem on a
74	* call to iio_device_register. */
75
76	/**
77	* struct iio_dev - industrial I/O device
78	* @id: [INTERN] used to identify device internally
79	* @dev_data: [DRIVER] device specific data
80	* @modes: [DRIVER] operating modes supported by device
81	* @currentmode: [DRIVER] current operating mode
82	* @dev: [DRIVER] device structure, should be assigned a parent
83	* and owner
84	* @attrs: [DRIVER] general purpose device attributes
85	* @driver_module: [DRIVER] module structure used to ensure correct
86	* ownership of chrdevs etc
87	* @num_interrupt_lines:[DRIVER] number of physical interrupt lines from device
88	* @interrupts: [INTERN] interrupt line specific event lists etc
89	* @event_attrs: [DRIVER] event control attributes
90	* @event_conf_attrs: [DRIVER] event configuration attributes
91	* @event_interfaces: [INTERN] event chrdevs associated with interrupt lines
92	* @ring: [DRIVER] any ring buffer present
93	* @mlock: [INTERN] lock used to prevent simultaneous device state
94	* changes
95	* @scan_el_attrs: [DRIVER] control of scan elements if that scan mode
96	* control method is used
97	* @scan_count: [INTERN] the number of elements in the current scan mode
98	* @scan_mask: [INTERN] bitmask used in masking scan mode elements
99	* @scan_timestamp: [INTERN] does the scan mode include a timestamp
100	* @trig: [INTERN] current device trigger (ring buffer modes)
101	* @pollfunc: [DRIVER] function run on trigger being recieved
102	**/
103	struct iio_dev {
104	int id;
105	void *dev_data;
106	int modes;
107	int currentmode;
108	struct device dev;
109	const struct attribute_group *attrs;
110	struct module *driver_module;
111
112	int num_interrupt_lines;
113	struct iio_interrupt **interrupts;
114	struct attribute_group *event_attrs;
115	struct attribute_group *event_conf_attrs;
116
117	struct iio_event_interface *event_interfaces;
118
119	struct iio_ring_buffer *ring;
120	struct mutex mlock;
121
122	struct attribute_group *scan_el_attrs;
123	int scan_count;
124
125	u16 scan_mask;
126	bool scan_timestamp;
127	struct iio_trigger *trig;
128	struct iio_poll_func *pollfunc;
129	};
130
131	/*
132	* These are mainly provided to allow for a change of implementation if a device
133	* has a large number of scan elements
134	*/
135	#define IIO_MAX_SCAN_LENGTH 15
136
137	static inline int iio_scan_mask_query(struct iio_dev *dev_info, int bit)
138	{
139	if (bit > IIO_MAX_SCAN_LENGTH)
140	return -EINVAL;
141	else
142	return !!(dev_info->scan_mask & (1 << bit));
143	};
144
145	static inline int iio_scan_mask_set(struct iio_dev *dev_info, int bit)
146	{
147	if (bit > IIO_MAX_SCAN_LENGTH)
148	return -EINVAL;
149	dev_info->scan_mask \|= (1 << bit);
150	dev_info->scan_count++;
151	return 0;
152	};
153
154	static inline int iio_scan_mask_clear(struct iio_dev *dev_info, int bit)
155	{
156	if (bit > IIO_MAX_SCAN_LENGTH)
157	return -EINVAL;
158	dev_info->scan_mask &= ~(1 << bit);
159	dev_info->scan_count--;
160	return 0;
161	};
162
163	/**
164	* iio_scan_mask_count_to_right() - how many scan elements occur before here
165	* @dev_info: the iio_device whose scan mode we are querying
166	* @bit: which number scan element is this
167	**/
168	static inline int iio_scan_mask_count_to_right(struct iio_dev *dev_info,
4c572605	169	int bit)
847ec80b JC	170	{
	171	int count = 0;
	172	int mask = (1 << bit);
	173	if (bit > IIO_MAX_SCAN_LENGTH)
	174	return -EINVAL;
	175	while (mask) {
	176	mask >>= 1;
	177	if (mask & dev_info->scan_mask)
	178	count++;
	179	}
	180
	181	return count;
	182	}
	183
	184	/**
	185	* iio_device_register() - register a device with the IIO subsystem
	186	* @dev_info: Device structure filled by the device driver
	187	**/
	188	int iio_device_register(struct iio_dev *dev_info);
	189
	190	/**
	191	* iio_device_unregister() - unregister a device from the IIO subsystem
	192	* @dev_info: Device structure representing the device.
	193	**/
	194	void iio_device_unregister(struct iio_dev *dev_info);
	195
	196	/**
	197	* struct iio_interrupt - wrapper used to allow easy handling of multiple
	198	* physical interrupt lines
	199	* @dev_info: the iio device for which the is an interrupt line
	200	* @line_number: associated line number
	201	* @id: idr allocated unique id number
	202	* @irq: associate interrupt number
	203	* @ev_list: event handler list for associated events
	204	* @ev_list_lock: ensure only one access to list at a time
	205	**/
	206	struct iio_interrupt {
	207	struct iio_dev *dev_info;
	208	int line_number;
	209	int id;
	210	int irq;
	211	struct list_head ev_list;
	212	spinlock_t ev_list_lock;
	213	};
	214
	215	#define to_iio_interrupt(i) container_of(i, struct iio_interrupt, ev_list)
	216
	217	/**
	218	* iio_register_interrupt_line() - Tell IIO about interrupt lines
	219	*
	220	* @irq: Typically provided via platform data
	221	* @dev_info: IIO device info structure for device
	222	* @line_number: Which interrupt line of the device is this?
	223	* @type: Interrupt type (e.g. edge triggered etc)
	224	* @name: Identifying name.
	225	**/
	226	int iio_register_interrupt_line(unsigned int irq,
	227	struct iio_dev *dev_info,
	228	int line_number,
	229	unsigned long type,
	230	const char *name);
	231
	232	void iio_unregister_interrupt_line(struct iio_dev *dev_info,
	233	int line_number);
234
235
236
237	/**
238	* iio_push_event() - try to add event to the list for userspace reading
239	* @dev_info: IIO device structure
240	* @ev_line: Which event line (hardware interrupt)
241	* @ev_code: What event
4c572605	242	* @timestamp: When the event occurred
847ec80b JC	243	**/
	244	int iio_push_event(struct iio_dev *dev_info,
	245	int ev_line,
	246	int ev_code,
	247	s64 timestamp);
	248
	249	/**
	250	* struct iio_work_cont - container for when singleton handler case matters
4c572605 RD	251	* @ws: [DEVICE] work_struct when not only possible event
	252	* @ws_nocheck: [DEVICE] work_struct when only possible event
	253	* @address: [DEVICE] associated register address
	254	* @mask: [DEVICE] associated mask for identifying event source
	255	* @st: [DEVICE] device specific state information
847ec80b JC	256	**/
	257	struct iio_work_cont {
	258	struct work_struct ws;
	259	struct work_struct ws_nocheck;
	260	int address;
	261	int mask;
	262	void *st;
	263	};
	264
	265	#define to_iio_work_cont_check(_ws) \
	266	container_of(_ws, struct iio_work_cont, ws)
	267
	268	#define to_iio_work_cont_no_check(_ws) \
	269	container_of(_ws, struct iio_work_cont, ws_nocheck)
	270
	271	/**
	272	* iio_init_work_cont() - intiialize the elements of a work container
	273	* @cont: the work container
	274	* @_checkfunc: function called when there are multiple possible int sources
	275	* @_nocheckfunc: function for when there is only one int source
4c572605 RD	276	* @_add: driver dependent, typically a register address
	277	* @_mask: driver dependent, typically a bit mask for a register
	278	* @_st: driver dependent, typically pointer to a device state structure
847ec80b JC	279	**/
	280	static inline void
	281	iio_init_work_cont(struct iio_work_cont *cont,
	282	void (_checkfunc)(struct work_struct ),
	283	void (_nocheckfunc)(struct work_struct ),
	284	int _add, int _mask, void *_st)
	285	{
	286	INIT_WORK(&(cont)->ws, _checkfunc);
	287	INIT_WORK(&(cont)->ws_nocheck, _nocheckfunc);
	288	cont->address = _add;
	289	cont->mask = _mask;
	290	cont->st = _st;
	291	}
	292	/**
4c572605	293	* __iio_push_event() - tries to add an event to the list associated with a chrdev
847ec80b JC	294	* @ev_int: the event interface to which we are pushing the event
	295	* @ev_code: the outgoing event code
	296	* @timestamp: timestamp of the event
	297	* @shared_pointer_p: the shared event pointer
	298	**/
	299	int __iio_push_event(struct iio_event_interface *ev_int,
	300	int ev_code,
	301	s64 timestamp,
	302	struct iio_shared_ev_pointer*
	303	shared_pointer_p);
	304	/**
4c572605 RD	305	* __iio_change_event() - change an event code in case of event escalation
4c572605 RD	306	* @ev: the event to be changed
847ec80b JC	307	* @ev_code: new event code
	308	* @timestamp: new timestamp
	309	**/
	310	void __iio_change_event(struct iio_detected_event_list *ev,
	311	int ev_code,
	312	s64 timestamp);
	313
	314	/**
4c572605	315	* iio_setup_ev_int() - configure an event interface (chrdev)
847ec80b JC	316	* @name: name used for resulting sysfs directory etc.
	317	* @ev_int: interface we are configuring
	318	* @owner: module that is responsible for registering this ev_int
	319	* @dev: device whose ev_int this is
	320	**/
	321	int iio_setup_ev_int(struct iio_event_interface *ev_int,
	322	const char *name,
	323	struct module *owner,
	324	struct device *dev);
	325
	326	void iio_free_ev_int(struct iio_event_interface *ev_int);
	327
	328	/**
	329	* iio_allocate_chrdev() - Allocate a chrdev
	330	* @handler: struct that contains relevant file handling for chrdev
	331	* @dev_info: iio_dev for which chrdev is being created
	332	**/
	333	int iio_allocate_chrdev(struct iio_handler handler, struct iio_dev dev_info);
	334	void iio_deallocate_chrdev(struct iio_handler *handler);
	335
	336	/* Used to distinguish between bipolar and unipolar scan elemenents.
	337	* Whilst this may seem obvious, we may well want to change the representation
	338	* in the future!*/
	339	#define IIO_SIGNED(a) -(a)
	340	#define IIO_UNSIGNED(a) (a)
	341
	342	extern dev_t iio_devt;
	343	extern struct class iio_class;
	344
	345	/**
4c572605	346	* iio_put_device() - reference counted deallocation of struct device
847ec80b JC	347	* @dev: the iio_device containing the device
	348	**/
	349	static inline void iio_put_device(struct iio_dev *dev)
	350	{
	351	if (dev)
	352	put_device(&dev->dev);
	353	};
	354
	355	/**
4c572605	356	* to_iio_dev() - get iio_dev for which we have the struct device
847ec80b JC	357	* @d: the struct device
	358	**/
	359	static inline struct iio_dev to_iio_dev(struct device d)
	360	{
	361	return container_of(d, struct iio_dev, dev);
	362	};
	363
	364	/**
	365	* iio_dev_get_devdata() - helper function gets device specific data
	366	* @d: the iio_dev associated with the device
	367	**/
	368	static inline void iio_dev_get_devdata(struct iio_dev d)
	369	{
	370	return d->dev_data;
	371	}
	372
	373	/**
	374	* iio_allocate_device() - allocate an iio_dev from a driver
	375	**/
	376	struct iio_dev *iio_allocate_device(void);
	377
	378	/**
	379	* iio_free_device() - free an iio_dev from a driver
4c572605	380	* @dev: the iio_dev associated with the device
847ec80b JC	381	**/
	382	void iio_free_device(struct iio_dev *dev);
	383
	384	/**
	385	* iio_put() - internal module reference count reduce
	386	**/
	387	void iio_put(void);
	388
	389	/**
	390	* iio_get() - internal module reference count increase
	391	**/
	392	void iio_get(void);
	393
	394	/* Ring buffer related */
	395	int iio_device_get_chrdev_minor(void);
	396	void iio_device_free_chrdev_minor(int val);
	397
	398	/**
4c572605 RD	399	* iio_ring_enabled() - helper function to test if any form of ring is enabled
4c572605 RD	400	* @dev_info: IIO device info structure for device
847ec80b JC	401	**/
	402	static inline bool iio_ring_enabled(struct iio_dev *dev_info)
	403	{
	404	return dev_info->currentmode
	405	& (INDIO_RING_TRIGGERED
	406	\| INDIO_RING_HARDWARE_BUFFER);
	407	};
	408
	409	struct idr;
	410
	411	int iio_get_new_idr_val(struct idr *this_idr);
	412	void iio_free_idr_val(struct idr *this_idr, int id);
	413	#endif /* _INDUSTRIAL_IO_H_ */