summaryrefslogtreecommitdiffstats
path: root/include/linux/iio/trigger.h
blob: 42da55dc3aa73fd5bc7c2a200e9b3529eca77bc1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
/* SPDX-License-Identifier: GPL-2.0-only */
/* The industrial I/O core, trigger handling functions
 *
 * Copyright (c) 2008 Jonathan Cameron
 */
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/atomic.h>

#ifndef _IIO_TRIGGER_H_
#define _IIO_TRIGGER_H_

#ifdef CONFIG_IIO_TRIGGER
struct iio_subirq {
	bool enabled;
};

struct iio_dev;
struct iio_trigger;

/**
 * struct iio_trigger_ops - operations structure for an iio_trigger.
 * @set_trigger_state:	switch on/off the trigger on demand
 * @reenable:		function to reenable the trigger when the
 *			use count is zero (may be NULL)
 * @validate_device:	function to validate the device when the
 *			current trigger gets changed.
 *
 * This is typically static const within a driver and shared by
 * instances of a given device.
 **/
struct iio_trigger_ops {
	int (*set_trigger_state)(struct iio_trigger *trig, bool state);
	void (*reenable)(struct iio_trigger *trig);
	int (*validate_device)(struct iio_trigger *trig,
			       struct iio_dev *indio_dev);
};


/**
 * struct iio_trigger - industrial I/O trigger device
 * @ops:		[DRIVER] operations structure
 * @owner:		[INTERN] owner of this driver module
 * @id:			[INTERN] unique id number
 * @name:		[DRIVER] unique name
 * @dev:		[DRIVER] associated device (if relevant)
 * @list:		[INTERN] used in maintenance of global trigger list
 * @alloc_list:		[DRIVER] used for driver specific trigger list
 * @use_count:		[INTERN] use count for the trigger.
 * @subirq_chip:	[INTERN] associate 'virtual' irq chip.
 * @subirq_base:	[INTERN] base number for irqs provided by trigger.
 * @subirqs:		[INTERN] information about the 'child' irqs.
 * @pool:		[INTERN] bitmap of irqs currently in use.
 * @pool_lock:		[INTERN] protection of the irq pool.
 * @attached_own_device:[INTERN] if we are using our own device as trigger,
 *			i.e. if we registered a poll function to the same
 *			device as the one providing the trigger.
 * @reenable_work:	[INTERN] work item used to ensure reenable can sleep.
 **/
struct iio_trigger {
	const struct iio_trigger_ops	*ops;
	struct module			*owner;
	int				id;
	const char			*name;
	struct device			dev;

	struct list_head		list;
	struct list_head		alloc_list;
	atomic_t			use_count;

	struct irq_chip			subirq_chip;
	int				subirq_base;

	struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
	unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
	struct mutex			pool_lock;
	bool				attached_own_device;
	struct work_struct		reenable_work;
};


static inline struct iio_trigger *to_iio_trigger(struct device *d)
{
	return container_of(d, struct iio_trigger, dev);
}

static inline void iio_trigger_put(struct iio_trigger *trig)
{
	module_put(trig->owner);
	put_device(&trig->dev);
}

static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
{
	get_device(&trig->dev);

	WARN_ONCE(list_empty(&trig->list),
		  "Getting non-registered iio trigger %s is prohibited\n",
		  trig->name);

	__module_get(trig->owner);

	return trig;
}

/**
 * iio_trigger_set_drvdata() - Set trigger driver data
 * @trig: IIO trigger structure
 * @data: Driver specific data
 *
 * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
 * retrieved by iio_trigger_get_drvdata().
 */
static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
{
	dev_set_drvdata(&trig->dev, data);
}

/**
 * iio_trigger_get_drvdata() - Get trigger driver data
 * @trig: IIO trigger structure
 *
 * Returns the data previously set with iio_trigger_set_drvdata()
 */
static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
{
	return dev_get_drvdata(&trig->dev);
}

/**
 * iio_trigger_register() - register a trigger with the IIO core
 * @trig_info:	trigger to be registered
 **/
int iio_trigger_register(struct iio_trigger *trig_info);

int devm_iio_trigger_register(struct device *dev,
			      struct iio_trigger *trig_info);

/**
 * iio_trigger_unregister() - unregister a trigger from the core
 * @trig_info:	trigger to be unregistered
 **/
void iio_trigger_unregister(struct iio_trigger *trig_info);

/**
 * iio_trigger_set_immutable() - set an immutable trigger on destination
 *
 * @indio_dev: IIO device structure containing the device
 * @trig: trigger to assign to device
 *
 **/
int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);

void iio_trigger_poll(struct iio_trigger *trig);
void iio_trigger_poll_chained(struct iio_trigger *trig);

irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);

#define iio_trigger_alloc(parent, fmt, ...) \
	__iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__)

__printf(3, 4)
struct iio_trigger *__iio_trigger_alloc(struct device *parent,
					struct module *this_mod,
					const char *fmt, ...);
void iio_trigger_free(struct iio_trigger *trig);

/**
 * iio_trigger_using_own() - tells us if we use our own HW trigger ourselves
 * @indio_dev:  device to check
 */
bool iio_trigger_using_own(struct iio_dev *indio_dev);

int iio_trigger_validate_own_device(struct iio_trigger *trig,
				     struct iio_dev *indio_dev);

#else
struct iio_trigger;
struct iio_trigger_ops;
#endif
#endif /* _IIO_TRIGGER_H_ */