tjh.dev
Linux kernel mirror (for testing)
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linux
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
11#ifndef _IIO_TRIGGER_H_
12#define _IIO_TRIGGER_H_
13
14struct iio_subirq {
15 bool enabled;
16};
17
18/**
19 * struct iio_trigger - industrial I/O trigger device
20 *
21 * @id: [INTERN] unique id number
22 * @name: [DRIVER] unique name
23 * @dev: [DRIVER] associated device (if relevant)
24 * @private_data: [DRIVER] device specific data
25 * @list: [INTERN] used in maintenance of global trigger list
26 * @alloc_list: [DRIVER] used for driver specific trigger list
27 * @owner: [DRIVER] used to monitor usage count of the trigger.
28 * @use_count: use count for the trigger
29 * @set_trigger_state: [DRIVER] switch on/off the trigger on demand
30 * @try_reenable: function to reenable the trigger when the
31 * use count is zero (may be NULL)
32 * @validate_device: function to validate the device when the
33 * current trigger gets changed.
34 * @subirq_chip: [INTERN] associate 'virtual' irq chip.
35 * @subirq_base: [INTERN] base number for irqs provided by trigger.
36 * @subirqs: [INTERN] information about the 'child' irqs.
37 * @pool: [INTERN] bitmap of irqs currently in use.
38 * @pool_lock: [INTERN] protection of the irq pool.
39 **/
40struct iio_trigger {
41 int id;
42 const char *name;
43 struct device dev;
44
45 void *private_data;
46 struct list_head list;
47 struct list_head alloc_list;
48 struct module *owner;
49 int use_count;
50
51 int (*set_trigger_state)(struct iio_trigger *trig, bool state);
52 int (*try_reenable)(struct iio_trigger *trig);
53 int (*validate_device)(struct iio_trigger *trig,
54 struct iio_dev *indio_dev);
55
56 struct irq_chip subirq_chip;
57 int subirq_base;
58
59 struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
60 unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
61 struct mutex pool_lock;
62};
63
64/**
65 * struct iio_poll_func - poll function pair
66 *
67 * @private_data: data specific to device (passed into poll func)
68 * @h: the function that is actually run on trigger
69 * @thread: threaded interrupt part
70 * @type: the type of interrupt (basically if oneshot)
71 * @name: name used to identify the trigger consumer.
72 * @irq: the corresponding irq as allocated from the
73 * trigger pool
74 * @timestamp: some devices need a timestamp grabbed as soon
75 * as possible after the trigger - hence handler
76 * passes it via here.
77 **/
78struct iio_poll_func {
79 void *private_data;
80 irqreturn_t (*h)(int irq, void *p);
81 irqreturn_t (*thread)(int irq, void *p);
82 int type;
83 char *name;
84 int irq;
85 s64 timestamp;
86};
87
88static inline struct iio_trigger *to_iio_trigger(struct device *d)
89{
90 return container_of(d, struct iio_trigger, dev);
91};
92
93static inline void iio_put_trigger(struct iio_trigger *trig)
94{
95 put_device(&trig->dev);
96 module_put(trig->owner);
97};
98
99static inline void iio_get_trigger(struct iio_trigger *trig)
100{
101 __module_get(trig->owner);
102 get_device(&trig->dev);
103};
104
105/**
106 * iio_trigger_register() - register a trigger with the IIO core
107 * @trig_info: trigger to be registered
108 **/
109int iio_trigger_register(struct iio_trigger *trig_info);
110
111/**
112 * iio_trigger_unregister() - unregister a trigger from the core
113 * @trig_info: trigger to be unregistered
114 **/
115void iio_trigger_unregister(struct iio_trigger *trig_info);
116
117/**
118 * iio_trigger_attach_poll_func() - add a function pair to be run on trigger
119 * @trig: trigger to which the function pair are being added
120 * @pf: poll function pair
121 **/
122int iio_trigger_attach_poll_func(struct iio_trigger *trig,
123 struct iio_poll_func *pf);
124
125/**
126 * iio_trigger_dettach_poll_func() - remove function pair from those to be
127 * run on trigger
128 * @trig: trigger from which the function is being removed
129 * @pf: poll function pair
130 **/
131int iio_trigger_dettach_poll_func(struct iio_trigger *trig,
132 struct iio_poll_func *pf);
133
134/**
135 * iio_trigger_poll() - called on a trigger occurring
136 * @trig: trigger which occurred
137 *
138 * Typically called in relevant hardware interrupt handler.
139 **/
140void iio_trigger_poll(struct iio_trigger *trig, s64 time);
141void iio_trigger_poll_chained(struct iio_trigger *trig, s64 time);
142void iio_trigger_notify_done(struct iio_trigger *trig);
143
144irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
145
146static inline int iio_trigger_get_irq(struct iio_trigger *trig)
147{
148 int ret;
149 mutex_lock(&trig->pool_lock);
150 ret = bitmap_find_free_region(trig->pool,
151 CONFIG_IIO_CONSUMERS_PER_TRIGGER,
152 ilog2(1));
153 mutex_unlock(&trig->pool_lock);
154 if (ret >= 0)
155 ret += trig->subirq_base;
156
157 return ret;
158};
159
160static inline void iio_trigger_put_irq(struct iio_trigger *trig, int irq)
161{
162 mutex_lock(&trig->pool_lock);
163 clear_bit(irq - trig->subirq_base, trig->pool);
164 mutex_unlock(&trig->pool_lock);
165};
166
167struct iio_poll_func
168*iio_alloc_pollfunc(irqreturn_t (*h)(int irq, void *p),
169 irqreturn_t (*thread)(int irq, void *p),
170 int type,
171 void *private,
172 const char *fmt,
173 ...);
174void iio_dealloc_pollfunc(struct iio_poll_func *pf);
175irqreturn_t iio_pollfunc_store_time(int irq, void *p);
176
177/*
178 * Two functions for common case where all that happens is a pollfunc
179 * is attached and detached from a trigger
180 */
181int iio_triggered_ring_postenable(struct iio_dev *indio_dev);
182int iio_triggered_ring_predisable(struct iio_dev *indio_dev);
183
184struct iio_trigger *iio_allocate_trigger(const char *fmt, ...)
185 __attribute__((format(printf, 1, 2)));
186void iio_free_trigger(struct iio_trigger *trig);
187
188#endif /* _IIO_TRIGGER_H_ */