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 * @set_trigger_state: switch on/off the trigger on demand
27 * @try_reenable: function to reenable the trigger when the
28 * use count is zero (may be NULL)
29 * @validate_device: function to validate the device when the
30 * current trigger gets changed.
31 *
32 * This is typically static const within a driver and shared by
33 * instances of a given device.
34 **/
35 struct iio_trigger_ops {
36 int (*set_trigger_state)(struct iio_trigger *trig, bool state);
37 int (*try_reenable)(struct iio_trigger *trig);
38 int (*validate_device)(struct iio_trigger *trig,
39 struct iio_dev *indio_dev);
40 };
41
42
43 /**
44 * struct iio_trigger - industrial I/O trigger device
45 * @ops: [DRIVER] operations structure
46 * @owner: [INTERN] owner of this driver module
47 * @id: [INTERN] unique id number
48 * @name: [DRIVER] unique name
49 * @dev: [DRIVER] associated device (if relevant)
50 * @list: [INTERN] used in maintenance of global trigger list
51 * @alloc_list: [DRIVER] used for driver specific trigger list
52 * @use_count: [INTERN] use count for the trigger.
53 * @subirq_chip: [INTERN] associate 'virtual' irq chip.
54 * @subirq_base: [INTERN] base number for irqs provided by trigger.
55 * @subirqs: [INTERN] information about the 'child' irqs.
56 * @pool: [INTERN] bitmap of irqs currently in use.
57 * @pool_lock: [INTERN] protection of the irq pool.
58 * @attached_own_device:[INTERN] if we are using our own device as trigger,
59 * i.e. if we registered a poll function to the same
60 * device as the one providing the trigger.
61 **/
62 struct iio_trigger {
63 const struct iio_trigger_ops *ops;
64 struct module *owner;
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->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->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 #define iio_trigger_register(trig_info) \
131 __iio_trigger_register((trig_info), THIS_MODULE)
132 int __iio_trigger_register(struct iio_trigger *trig_info,
133 struct module *this_mod);
134
135 #define devm_iio_trigger_register(dev, trig_info) \
136 __devm_iio_trigger_register((dev), (trig_info), THIS_MODULE)
137 int __devm_iio_trigger_register(struct device *dev,
138 struct iio_trigger *trig_info,
139 struct module *this_mod);
140
141 /**
142 * iio_trigger_unregister() - unregister a trigger from the core
143 * @trig_info: trigger to be unregistered
144 **/
145 void iio_trigger_unregister(struct iio_trigger *trig_info);
146
147 void devm_iio_trigger_unregister(struct device *dev,
148 struct iio_trigger *trig_info);
149
150 /**
151 * iio_trigger_set_immutable() - set an immutable trigger on destination
152 *
153 * @indio_dev: IIO device structure containing the device
154 * @trig: trigger to assign to device
155 *
156 **/
157 int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
158
159 /**
160 * iio_trigger_poll() - called on a trigger occurring
161 * @trig: trigger which occurred
162 *
163 * Typically called in relevant hardware interrupt handler.
164 **/
165 void iio_trigger_poll(struct iio_trigger *trig);
166 void iio_trigger_poll_chained(struct iio_trigger *trig);
167
168 irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
169
170 __printf(1, 2) struct iio_trigger *iio_trigger_alloc(const char *fmt, ...);
171 void iio_trigger_free(struct iio_trigger *trig);
172
173 /**
174 * iio_trigger_using_own() - tells us if we use our own HW trigger ourselves
175 * @indio_dev: device to check
176 */
177 bool iio_trigger_using_own(struct iio_dev *indio_dev);
178
179 int iio_trigger_validate_own_device(struct iio_trigger *trig,
180 struct iio_dev *indio_dev);
181
182 #else
183 struct iio_trigger;
184 struct iio_trigger_ops;
185 #endif
186 #endif /* _IIO_TRIGGER_H_ */
187