trigger.h

  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
 14struct iio_subirq {
 15	bool enabled;
 16};
 17
 18struct iio_dev;
 19struct 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 **/
 32struct 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 * @reenable_work:	[INTERN] work item used to ensure reenable can sleep.
 59 **/
 60struct iio_trigger {
 61	const struct iio_trigger_ops	*ops;
 62	struct module			*owner;
 63	int				id;
 64	const char			*name;
 65	struct device			dev;
 66
 67	struct list_head		list;
 68	struct list_head		alloc_list;
 69	atomic_t			use_count;
 70
 71	struct irq_chip			subirq_chip;
 72	int				subirq_base;
 73
 74	struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
 75	unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
 76	struct mutex			pool_lock;
 77	bool				attached_own_device;
 78	struct work_struct		reenable_work;
 79};
 80
 81
 82static inline struct iio_trigger *to_iio_trigger(struct device *d)
 83{
 84	return container_of(d, struct iio_trigger, dev);
 85}
 86
 87static inline void iio_trigger_put(struct iio_trigger *trig)
 88{
 89	module_put(trig->owner);
 90	put_device(&trig->dev);
 91}
 92
 93static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
 94{
 95	get_device(&trig->dev);
 96
 97	WARN_ONCE(list_empty(&trig->list),
 98		  "Getting non-registered iio trigger %s is prohibited\n",
 99		  trig->name);
100
101	__module_get(trig->owner);
102
103	return trig;
104}
105
106/**
107 * iio_trigger_set_drvdata() - Set trigger driver data
108 * @trig: IIO trigger structure
109 * @data: Driver specific data
110 *
111 * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
112 * retrieved by iio_trigger_get_drvdata().
113 */
114static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
115{
116	dev_set_drvdata(&trig->dev, data);
117}
118
119/**
120 * iio_trigger_get_drvdata() - Get trigger driver data
121 * @trig: IIO trigger structure
122 *
123 * Returns the data previously set with iio_trigger_set_drvdata()
124 */
125static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
126{
127	return dev_get_drvdata(&trig->dev);
128}
129
130/**
131 * iio_trigger_register() - register a trigger with the IIO core
132 * @trig_info:	trigger to be registered
133 **/
134int iio_trigger_register(struct iio_trigger *trig_info);
135
136int devm_iio_trigger_register(struct device *dev,
137			      struct iio_trigger *trig_info);
138
139/**
140 * iio_trigger_unregister() - unregister a trigger from the core
141 * @trig_info:	trigger to be unregistered
142 **/
143void iio_trigger_unregister(struct iio_trigger *trig_info);
144
145/**
146 * iio_trigger_set_immutable() - set an immutable trigger on destination
147 *
148 * @indio_dev: IIO device structure containing the device
149 * @trig: trigger to assign to device
150 *
151 **/
152int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
153
154void iio_trigger_poll(struct iio_trigger *trig);
155void iio_trigger_poll_nested(struct iio_trigger *trig);
156
157irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
158
159#define iio_trigger_alloc(parent, fmt, ...) \
160	__iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__)
161
162__printf(3, 4)
163struct iio_trigger *__iio_trigger_alloc(struct device *parent,
164					struct module *this_mod,
165					const char *fmt, ...);
166void 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 */
172bool iio_trigger_using_own(struct iio_dev *indio_dev);
173
174int iio_validate_own_trigger(struct iio_dev *idev, struct iio_trigger *trig);
175int iio_trigger_validate_own_device(struct iio_trigger *trig,
176				     struct iio_dev *indio_dev);
177
178#else
179struct iio_trigger;
180struct iio_trigger_ops;
181#endif
182#endif /* _IIO_TRIGGER_H_ */