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
14 struct iio_subirq {
15 	bool enabled;
16 };
17 
18 struct iio_dev;
19 struct 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  **/
32 struct 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  **/
59 struct iio_trigger {
60 	const struct iio_trigger_ops	*ops;
61 	struct module			*owner;
62 	int				id;
63 	const char			*name;
64 	struct device			dev;
65 
66 	struct list_head		list;
67 	struct list_head		alloc_list;
68 	atomic_t			use_count;
69 
70 	struct irq_chip			subirq_chip;
71 	int				subirq_base;
72 
73 	struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
74 	unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
75 	struct mutex			pool_lock;
76 	bool				attached_own_device;
77 };
78 
79 
to_iio_trigger(struct device * d)80 static inline struct iio_trigger *to_iio_trigger(struct device *d)
81 {
82 	return container_of(d, struct iio_trigger, dev);
83 }
84 
iio_trigger_put(struct iio_trigger * trig)85 static inline void iio_trigger_put(struct iio_trigger *trig)
86 {
87 	module_put(trig->owner);
88 	put_device(&trig->dev);
89 }
90 
iio_trigger_get(struct iio_trigger * trig)91 static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
92 {
93 	get_device(&trig->dev);
94 	__module_get(trig->owner);
95 
96 	return trig;
97 }
98 
99 /**
100  * iio_trigger_set_drvdata() - Set trigger driver data
101  * @trig: IIO trigger structure
102  * @data: Driver specific data
103  *
104  * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
105  * retrieved by iio_trigger_get_drvdata().
106  */
iio_trigger_set_drvdata(struct iio_trigger * trig,void * data)107 static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
108 {
109 	dev_set_drvdata(&trig->dev, data);
110 }
111 
112 /**
113  * iio_trigger_get_drvdata() - Get trigger driver data
114  * @trig: IIO trigger structure
115  *
116  * Returns the data previously set with iio_trigger_set_drvdata()
117  */
iio_trigger_get_drvdata(struct iio_trigger * trig)118 static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
119 {
120 	return dev_get_drvdata(&trig->dev);
121 }
122 
123 /**
124  * iio_trigger_register() - register a trigger with the IIO core
125  * @trig_info:	trigger to be registered
126  **/
127 #define iio_trigger_register(trig_info) \
128 	__iio_trigger_register((trig_info), THIS_MODULE)
129 int __iio_trigger_register(struct iio_trigger *trig_info,
130 			   struct module *this_mod);
131 
132 #define devm_iio_trigger_register(dev, trig_info) \
133 	__devm_iio_trigger_register((dev), (trig_info), THIS_MODULE)
134 int __devm_iio_trigger_register(struct device *dev,
135 				struct iio_trigger *trig_info,
136 				struct module *this_mod);
137 
138 /**
139  * iio_trigger_unregister() - unregister a trigger from the core
140  * @trig_info:	trigger to be unregistered
141  **/
142 void iio_trigger_unregister(struct iio_trigger *trig_info);
143 
144 /**
145  * iio_trigger_set_immutable() - set an immutable trigger on destination
146  *
147  * @indio_dev: IIO device structure containing the device
148  * @trig: trigger to assign to device
149  *
150  **/
151 int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
152 
153 /**
154  * iio_trigger_poll() - called on a trigger occurring
155  * @trig:	trigger which occurred
156  *
157  * Typically called in relevant hardware interrupt handler.
158  **/
159 void iio_trigger_poll(struct iio_trigger *trig);
160 void iio_trigger_poll_chained(struct iio_trigger *trig);
161 
162 irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
163 
164 __printf(2, 3)
165 struct iio_trigger *iio_trigger_alloc(struct device *parent, const char *fmt, ...);
166 void 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  */
172 bool iio_trigger_using_own(struct iio_dev *indio_dev);
173 
174 int iio_trigger_validate_own_device(struct iio_trigger *trig,
175 				     struct iio_dev *indio_dev);
176 
177 #else
178 struct iio_trigger;
179 struct iio_trigger_ops;
180 #endif
181 #endif /* _IIO_TRIGGER_H_ */
182