trigger.h revision 99c978529a40132a6f7a5f136b4362b56fc88d8c 
1/* The industrial I/O core, trigger handling functions
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#include <linux/irq.h>
10#include <linux/module.h>
11
12#ifndef _IIO_TRIGGER_H_
13#define _IIO_TRIGGER_H_
14
15struct iio_subirq {
16	bool enabled;
17};
18
19/**
20 * struct iio_trigger_ops - operations structure for an iio_trigger.
21 * @owner:		used to monitor usage count of the trigger.
22 * @set_trigger_state:	switch on/off the trigger on demand
23 * @try_reenable:	function to reenable the trigger when the
24 *			use count is zero (may be NULL)
25 * @validate_device:	function to validate the device when the
26 *			current trigger gets changed.
27 *
28 * This is typically static const within a driver and shared by
29 * instances of a given device.
30 **/
31struct iio_trigger_ops {
32	struct module			*owner;
33	int (*set_trigger_state)(struct iio_trigger *trig, bool state);
34	int (*try_reenable)(struct iio_trigger *trig);
35	int (*validate_device)(struct iio_trigger *trig,
36			       struct iio_dev *indio_dev);
37};
38
39
40/**
41 * struct iio_trigger - industrial I/O trigger device
42 *
43 * @id:			[INTERN] unique id number
44 * @name:		[DRIVER] unique name
45 * @dev:		[DRIVER] associated device (if relevant)
46 * @private_data:	[DRIVER] device specific data
47 * @list:		[INTERN] used in maintenance of global trigger list
48 * @alloc_list:		[DRIVER] used for driver specific trigger list
49 * @owner:		[DRIVER] used to monitor usage count of the trigger.
50 * @use_count:		use count for the trigger
51 * @subirq_chip:	[INTERN] associate 'virtual' irq chip.
52 * @subirq_base:	[INTERN] base number for irqs provided by trigger.
53 * @subirqs:		[INTERN] information about the 'child' irqs.
54 * @pool:		[INTERN] bitmap of irqs currently in use.
55 * @pool_lock:		[INTERN] protection of the irq pool.
56 **/
57struct iio_trigger {
58	const struct iio_trigger_ops	*ops;
59	int				id;
60	const char			*name;
61	struct device			dev;
62
63	void				*private_data;
64	struct list_head		list;
65	struct list_head		alloc_list;
66	struct module			*owner;
67	int use_count;
68
69	struct irq_chip			subirq_chip;
70	int				subirq_base;
71
72	struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
73	unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
74	struct mutex			pool_lock;
75};
76
77
78static inline struct iio_trigger *to_iio_trigger(struct device *d)
79{
80	return container_of(d, struct iio_trigger, dev);
81};
82
83static inline void iio_put_trigger(struct iio_trigger *trig)
84{
85	module_put(trig->ops->owner);
86	put_device(&trig->dev);
87};
88
89static inline void iio_get_trigger(struct iio_trigger *trig)
90{
91	get_device(&trig->dev);
92	__module_get(trig->ops->owner);
93};
94
95/**
96 * iio_trigger_register() - register a trigger with the IIO core
97 * @trig_info:	trigger to be registered
98 **/
99int iio_trigger_register(struct iio_trigger *trig_info);
100
101/**
102 * iio_trigger_unregister() - unregister a trigger from the core
103 * @trig_info:	trigger to be unregistered
104 **/
105void iio_trigger_unregister(struct iio_trigger *trig_info);
106
107/**
108 * iio_trigger_poll() - called on a trigger occurring
109 * @trig: trigger which occurred
110 *
111 * Typically called in relevant hardware interrupt handler.
112 **/
113void iio_trigger_poll(struct iio_trigger *trig, s64 time);
114void iio_trigger_poll_chained(struct iio_trigger *trig, s64 time);
115
116irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
117
118struct iio_trigger *iio_allocate_trigger(const char *fmt, ...)
119	__attribute__((format(printf, 1, 2)));
120void iio_free_trigger(struct iio_trigger *trig);
121
122#endif /* _IIO_TRIGGER_H_ */
123