xref: /linux/include/linux/iio/trigger.h (revision 564eb714f5f09ac733c26860d5f0831f213fbdf1)
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 #include <linux/atomic.h>
12 
13 #ifndef _IIO_TRIGGER_H_
14 #define _IIO_TRIGGER_H_
15 
16 #ifdef CONFIG_IIO_TRIGGER
17 struct iio_subirq {
18 	bool enabled;
19 };
20 
21 /**
22  * struct iio_trigger_ops - operations structure for an iio_trigger.
23  * @owner:		used to monitor usage count of the trigger.
24  * @set_trigger_state:	switch on/off the trigger on demand
25  * @try_reenable:	function to reenable the trigger when the
26  *			use count is zero (may be NULL)
27  * @validate_device:	function to validate the device when the
28  *			current trigger gets changed.
29  *
30  * This is typically static const within a driver and shared by
31  * instances of a given device.
32  **/
33 struct iio_trigger_ops {
34 	struct module *owner;
35 	int (*set_trigger_state)(struct iio_trigger *trig, bool state);
36 	int (*try_reenable)(struct iio_trigger *trig);
37 	int (*validate_device)(struct iio_trigger *trig,
38 			       struct iio_dev *indio_dev);
39 };
40 
41 
42 /**
43  * struct iio_trigger - industrial I/O trigger device
44  * @ops:		[DRIVER] operations structure
45  * @id:			[INTERN] unique id number
46  * @name:		[DRIVER] unique name
47  * @dev:		[DRIVER] associated device (if relevant)
48  * @list:		[INTERN] used in maintenance of global trigger list
49  * @alloc_list:		[DRIVER] used for driver specific trigger list
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  **/
57 struct iio_trigger {
58 	const struct iio_trigger_ops	*ops;
59 	int				id;
60 	const char			*name;
61 	struct device			dev;
62 
63 	struct list_head		list;
64 	struct list_head		alloc_list;
65 	atomic_t			use_count;
66 
67 	struct irq_chip			subirq_chip;
68 	int				subirq_base;
69 
70 	struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
71 	unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
72 	struct mutex			pool_lock;
73 };
74 
75 
76 static inline struct iio_trigger *to_iio_trigger(struct device *d)
77 {
78 	return container_of(d, struct iio_trigger, dev);
79 }
80 
81 static inline void iio_trigger_put(struct iio_trigger *trig)
82 {
83 	module_put(trig->ops->owner);
84 	put_device(&trig->dev);
85 }
86 
87 static inline void iio_trigger_get(struct iio_trigger *trig)
88 {
89 	get_device(&trig->dev);
90 	__module_get(trig->ops->owner);
91 }
92 
93 /**
94  * iio_device_set_drvdata() - Set trigger driver data
95  * @trig: IIO trigger structure
96  * @data: Driver specific data
97  *
98  * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
99  * retrieved by iio_trigger_get_drvdata().
100  */
101 static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
102 {
103 	dev_set_drvdata(&trig->dev, data);
104 }
105 
106 /**
107  * iio_trigger_get_drvdata() - Get trigger driver data
108  * @trig: IIO trigger structure
109  *
110  * Returns the data previously set with iio_trigger_set_drvdata()
111  */
112 static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
113 {
114 	return dev_get_drvdata(&trig->dev);
115 }
116 
117 /**
118  * iio_trigger_register() - register a trigger with the IIO core
119  * @trig_info:	trigger to be registered
120  **/
121 int iio_trigger_register(struct iio_trigger *trig_info);
122 
123 /**
124  * iio_trigger_unregister() - unregister a trigger from the core
125  * @trig_info:	trigger to be unregistered
126  **/
127 void iio_trigger_unregister(struct iio_trigger *trig_info);
128 
129 /**
130  * iio_trigger_poll() - called on a trigger occurring
131  * @trig:	trigger which occurred
132  * @time:	timestamp when trigger occurred
133  *
134  * Typically called in relevant hardware interrupt handler.
135  **/
136 void iio_trigger_poll(struct iio_trigger *trig, s64 time);
137 void iio_trigger_poll_chained(struct iio_trigger *trig, s64 time);
138 
139 irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
140 
141 __printf(1, 2) struct iio_trigger *iio_trigger_alloc(const char *fmt, ...);
142 void iio_trigger_free(struct iio_trigger *trig);
143 
144 #else
145 struct iio_trigger;
146 struct iio_trigger_ops;
147 #endif
148 #endif /* _IIO_TRIGGER_H_ */
149