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 int id;
66 const char *name;
67 struct device dev;
68
69 struct list_head list;
70 struct list_head alloc_list;
71 atomic_t use_count;
72
73 struct irq_chip subirq_chip;
74 int subirq_base;
75
76 struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
77 unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
78 struct mutex pool_lock;
79 bool attached_own_device;
80 };
81
82
to_iio_trigger(struct device * d)83 static inline struct iio_trigger *to_iio_trigger(struct device *d)
84 {
85 return container_of(d, struct iio_trigger, dev);
86 }
87
iio_trigger_put(struct iio_trigger * trig)88 static inline void iio_trigger_put(struct iio_trigger *trig)
89 {
90 module_put(trig->ops->owner);
91 put_device(&trig->dev);
92 }
93
iio_trigger_get(struct iio_trigger * trig)94 static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
95 {
96 get_device(&trig->dev);
97 __module_get(trig->ops->owner);
98
99 return trig;
100 }
101
102 /**
103 * iio_device_set_drvdata() - Set trigger driver data
104 * @trig: IIO trigger structure
105 * @data: Driver specific data
106 *
107 * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
108 * retrieved by iio_trigger_get_drvdata().
109 */
iio_trigger_set_drvdata(struct iio_trigger * trig,void * data)110 static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
111 {
112 dev_set_drvdata(&trig->dev, data);
113 }
114
115 /**
116 * iio_trigger_get_drvdata() - Get trigger driver data
117 * @trig: IIO trigger structure
118 *
119 * Returns the data previously set with iio_trigger_set_drvdata()
120 */
iio_trigger_get_drvdata(struct iio_trigger * trig)121 static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
122 {
123 return dev_get_drvdata(&trig->dev);
124 }
125
126 /**
127 * iio_trigger_register() - register a trigger with the IIO core
128 * @trig_info: trigger to be registered
129 **/
130 int iio_trigger_register(struct iio_trigger *trig_info);
131
132 int devm_iio_trigger_register(struct device *dev,
133 struct iio_trigger *trig_info);
134
135 /**
136 * iio_trigger_unregister() - unregister a trigger from the core
137 * @trig_info: trigger to be unregistered
138 **/
139 void iio_trigger_unregister(struct iio_trigger *trig_info);
140
141 void devm_iio_trigger_unregister(struct device *dev,
142 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(1, 2) struct iio_trigger *iio_trigger_alloc(const char *fmt, ...);
165 void iio_trigger_free(struct iio_trigger *trig);
166
167 /**
168 * iio_trigger_using_own() - tells us if we use our own HW trigger ourselves
169 * @indio_dev: device to check
170 */
171 bool iio_trigger_using_own(struct iio_dev *indio_dev);
172
173
174 #else
175 struct iio_trigger;
176 struct iio_trigger_ops;
177 #endif
178 #endif /* _IIO_TRIGGER_H_ */
179