xref: /linux-6.15/include/linux/iio/trigger.h (revision 873f3894)
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 struct iio_dev;
22 struct iio_trigger;
23 
24 /**
25  * struct iio_trigger_ops - operations structure for an iio_trigger.
26  * @owner:		used to monitor usage count of the trigger.
27  * @set_trigger_state:	switch on/off the trigger on demand
28  * @try_reenable:	function to reenable the trigger when the
29  *			use count is zero (may be NULL)
30  * @validate_device:	function to validate the device when the
31  *			current trigger gets changed.
32  *
33  * This is typically static const within a driver and shared by
34  * instances of a given device.
35  **/
36 struct iio_trigger_ops {
37 	struct module *owner;
38 	int (*set_trigger_state)(struct iio_trigger *trig, bool state);
39 	int (*try_reenable)(struct iio_trigger *trig);
40 	int (*validate_device)(struct iio_trigger *trig,
41 			       struct iio_dev *indio_dev);
42 };
43 
44 
45 /**
46  * struct iio_trigger - industrial I/O trigger device
47  * @ops:		[DRIVER] operations structure
48  * @id:			[INTERN] unique id number
49  * @name:		[DRIVER] unique name
50  * @dev:		[DRIVER] associated device (if relevant)
51  * @list:		[INTERN] used in maintenance of global trigger list
52  * @alloc_list:		[DRIVER] used for driver specific trigger list
53  * @use_count:		use count for the trigger
54  * @subirq_chip:	[INTERN] associate 'virtual' irq chip.
55  * @subirq_base:	[INTERN] base number for irqs provided by trigger.
56  * @subirqs:		[INTERN] information about the 'child' irqs.
57  * @pool:		[INTERN] bitmap of irqs currently in use.
58  * @pool_lock:		[INTERN] protection of the irq pool.
59  * @attached_own_device:[INTERN] if we are using our own device as trigger,
60  *			i.e. if we registered a poll function to the same
61  *			device as the one providing the trigger.
62  **/
63 struct iio_trigger {
64 	const struct iio_trigger_ops	*ops;
65 	struct module			*owner;
66 	int				id;
67 	const char			*name;
68 	struct device			dev;
69 
70 	struct list_head		list;
71 	struct list_head		alloc_list;
72 	atomic_t			use_count;
73 
74 	struct irq_chip			subirq_chip;
75 	int				subirq_base;
76 
77 	struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
78 	unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
79 	struct mutex			pool_lock;
80 	bool				attached_own_device;
81 };
82 
83 
84 static inline struct iio_trigger *to_iio_trigger(struct device *d)
85 {
86 	return container_of(d, struct iio_trigger, dev);
87 }
88 
89 static inline void iio_trigger_put(struct iio_trigger *trig)
90 {
91 	module_put(trig->owner);
92 	put_device(&trig->dev);
93 }
94 
95 static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
96 {
97 	get_device(&trig->dev);
98 	__module_get(trig->owner);
99 
100 	return trig;
101 }
102 
103 /**
104  * iio_device_set_drvdata() - Set trigger driver data
105  * @trig: IIO trigger structure
106  * @data: Driver specific data
107  *
108  * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
109  * retrieved by iio_trigger_get_drvdata().
110  */
111 static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
112 {
113 	dev_set_drvdata(&trig->dev, data);
114 }
115 
116 /**
117  * iio_trigger_get_drvdata() - Get trigger driver data
118  * @trig: IIO trigger structure
119  *
120  * Returns the data previously set with iio_trigger_set_drvdata()
121  */
122 static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
123 {
124 	return dev_get_drvdata(&trig->dev);
125 }
126 
127 /**
128  * iio_trigger_register() - register a trigger with the IIO core
129  * @trig_info:	trigger to be registered
130  **/
131 #define iio_trigger_register(trig_info) \
132 	__iio_trigger_register((trig_info), THIS_MODULE)
133 int __iio_trigger_register(struct iio_trigger *trig_info,
134 			   struct module *this_mod);
135 
136 #define devm_iio_trigger_register(dev, trig_info) \
137 	__devm_iio_trigger_register((dev), (trig_info), THIS_MODULE)
138 int __devm_iio_trigger_register(struct device *dev,
139 				struct iio_trigger *trig_info,
140 				struct module *this_mod);
141 
142 /**
143  * iio_trigger_unregister() - unregister a trigger from the core
144  * @trig_info:	trigger to be unregistered
145  **/
146 void iio_trigger_unregister(struct iio_trigger *trig_info);
147 
148 void devm_iio_trigger_unregister(struct device *dev,
149 				 struct iio_trigger *trig_info);
150 
151 /**
152  * iio_trigger_set_immutable() - set an immutable trigger on destination
153  *
154  * @indio_dev - IIO device structure containing the device
155  * @trig - trigger to assign to device
156  *
157  **/
158 int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
159 
160 /**
161  * iio_trigger_poll() - called on a trigger occurring
162  * @trig:	trigger which occurred
163  *
164  * Typically called in relevant hardware interrupt handler.
165  **/
166 void iio_trigger_poll(struct iio_trigger *trig);
167 void iio_trigger_poll_chained(struct iio_trigger *trig);
168 
169 irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
170 
171 __printf(1, 2) struct iio_trigger *iio_trigger_alloc(const char *fmt, ...);
172 void iio_trigger_free(struct iio_trigger *trig);
173 
174 /**
175  * iio_trigger_using_own() - tells us if we use our own HW trigger ourselves
176  * @indio_dev:  device to check
177  */
178 bool iio_trigger_using_own(struct iio_dev *indio_dev);
179 
180 int iio_trigger_validate_own_device(struct iio_trigger *trig,
181 				     struct iio_dev *indio_dev);
182 
183 #else
184 struct iio_trigger;
185 struct iio_trigger_ops;
186 #endif
187 #endif /* _IIO_TRIGGER_H_ */
188