1/* SPDX-License-Identifier: GPL-2.0-only */
2/* The industrial I/O core, trigger handling functions
3 *
4 * Copyright (c) 2008 Jonathan Cameron
5 */
6#include <linux/irq.h>
7#include <linux/module.h>
8#include <linux/atomic.h>
9
10#ifndef _IIO_TRIGGER_H_
11#define _IIO_TRIGGER_H_
12
13#ifdef CONFIG_IIO_TRIGGER
14struct iio_subirq {
15	bool enabled;
16};
17
18struct iio_dev;
19struct iio_trigger;
20
21/**
22 * struct iio_trigger_ops - operations structure for an iio_trigger.
23 * @set_trigger_state:	switch on/off the trigger on demand
24 * @reenable:		function to reenable the trigger when the
25 *			use count is zero (may be NULL)
26 * @validate_device:	function to validate the device when the
27 *			current trigger gets changed.
28 *
29 * This is typically static const within a driver and shared by
30 * instances of a given device.
31 **/
32struct iio_trigger_ops {
33	int (*set_trigger_state)(struct iio_trigger *trig, bool state);
34	void (*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 * @ops:		[DRIVER] operations structure
43 * @owner:		[INTERN] owner of this driver module
44 * @id:			[INTERN] unique id number
45 * @name:		[DRIVER] unique name
46 * @dev:		[DRIVER] associated device (if relevant)
47 * @list:		[INTERN] used in maintenance of global trigger list
48 * @alloc_list:		[DRIVER] used for driver specific trigger list
49 * @use_count:		[INTERN] use count for the trigger.
50 * @subirq_chip:	[INTERN] associate 'virtual' irq chip.
51 * @subirq_base:	[INTERN] base number for irqs provided by trigger.
52 * @subirqs:		[INTERN] information about the 'child' irqs.
53 * @pool:		[INTERN] bitmap of irqs currently in use.
54 * @pool_lock:		[INTERN] protection of the irq pool.
55 * @attached_own_device:[INTERN] if we are using our own device as trigger,
56 *			i.e. if we registered a poll function to the same
57 *			device as the one providing the trigger.
58 * @reenable_work:	[INTERN] work item used to ensure reenable can sleep.
59 **/
60struct iio_trigger {
61	const struct iio_trigger_ops	*ops;
62	struct module			*owner;
63	int				id;
64	const char			*name;
65	struct device			dev;
66
67	struct list_head		list;
68	struct list_head		alloc_list;
69	atomic_t			use_count;
70
71	struct irq_chip			subirq_chip;
72	int				subirq_base;
73
74	struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
75	unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
76	struct mutex			pool_lock;
77	bool				attached_own_device;
78	struct work_struct		reenable_work;
79};
80
81
82static inline struct iio_trigger *to_iio_trigger(struct device *d)
83{
84	return container_of(d, struct iio_trigger, dev);
85}
86
87static inline void iio_trigger_put(struct iio_trigger *trig)
88{
89	module_put(trig->owner);
90	put_device(&trig->dev);
91}
92
93static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
94{
95	get_device(&trig->dev);
96
97	WARN_ONCE(list_empty(&trig->list),
98		  "Getting non-registered iio trigger %s is prohibited\n",
99		  trig->name);
100
101	__module_get(trig->owner);
102
103	return trig;
104}
105
106/**
107 * iio_trigger_set_drvdata() - Set trigger driver data
108 * @trig: IIO trigger structure
109 * @data: Driver specific data
110 *
111 * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
112 * retrieved by iio_trigger_get_drvdata().
113 */
114static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
115{
116	dev_set_drvdata(&trig->dev, data);
117}
118
119/**
120 * iio_trigger_get_drvdata() - Get trigger driver data
121 * @trig: IIO trigger structure
122 *
123 * Returns the data previously set with iio_trigger_set_drvdata()
124 */
125static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
126{
127	return dev_get_drvdata(&trig->dev);
128}
129
130/**
131 * iio_trigger_register() - register a trigger with the IIO core
132 * @trig_info:	trigger to be registered
133 **/
134int iio_trigger_register(struct iio_trigger *trig_info);
135
136int devm_iio_trigger_register(struct device *dev,
137			      struct iio_trigger *trig_info);
138
139/**
140 * iio_trigger_unregister() - unregister a trigger from the core
141 * @trig_info:	trigger to be unregistered
142 **/
143void iio_trigger_unregister(struct iio_trigger *trig_info);
144
145/**
146 * iio_trigger_set_immutable() - set an immutable trigger on destination
147 *
148 * @indio_dev: IIO device structure containing the device
149 * @trig: trigger to assign to device
150 *
151 **/
152int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
153
154void iio_trigger_poll(struct iio_trigger *trig);
155void iio_trigger_poll_nested(struct iio_trigger *trig);
156
157irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
158
159#define iio_trigger_alloc(parent, fmt, ...) \
160	__iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__)
161
162__printf(3, 4)
163struct iio_trigger *__iio_trigger_alloc(struct device *parent,
164					struct module *this_mod,
165					const char *fmt, ...);
166void iio_trigger_free(struct iio_trigger *trig);
167
168/**
169 * iio_trigger_using_own() - tells us if we use our own HW trigger ourselves
170 * @indio_dev:  device to check
171 */
172bool iio_trigger_using_own(struct iio_dev *indio_dev);
173
174int iio_validate_own_trigger(struct iio_dev *idev, struct iio_trigger *trig);
175int iio_trigger_validate_own_device(struct iio_trigger *trig,
176				     struct iio_dev *indio_dev);
177
178#else
179struct iio_trigger;
180struct iio_trigger_ops;
181#endif
182#endif /* _IIO_TRIGGER_H_ */
183