LXR linux/include/linux/iio/trigger.h

   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
  17struct iio_subirq {
  18        bool enabled;
  19};
  20
  21/**
  22 * struct iio_trigger_ops - operations structure for an iio_trigger.
  23 * @owner:              used to monitor usage count of the trigger.
  24 * @set_trigger_state:  switch on/off the trigger on demand
  25 * @try_reenable:       function to reenable the trigger when the
  26 *                      use count is zero (may be NULL)
  27 * @validate_device:    function to validate the device when the
  28 *                      current trigger gets changed.
  29 *
  30 * This is typically static const within a driver and shared by
  31 * instances of a given device.
  32 **/
  33struct iio_trigger_ops {
  34        struct module *owner;
  35        int (*set_trigger_state)(struct iio_trigger *trig, bool state);
  36        int (*try_reenable)(struct iio_trigger *trig);
  37        int (*validate_device)(struct iio_trigger *trig,
  38                               struct iio_dev *indio_dev);
  39};
  40
  41
  42/**
  43 * struct iio_trigger - industrial I/O trigger device
  44 * @ops:                [DRIVER] operations structure
  45 * @id:                 [INTERN] unique id number
  46 * @name:               [DRIVER] unique name
  47 * @dev:                [DRIVER] associated device (if relevant)
  48 * @list:               [INTERN] used in maintenance of global trigger list
  49 * @alloc_list:         [DRIVER] used for driver specific trigger list
  50 * @use_count:          use count for the trigger
  51 * @subirq_chip:        [INTERN] associate 'virtual' irq chip.
  52 * @subirq_base:        [INTERN] base number for irqs provided by trigger.
  53 * @subirqs:            [INTERN] information about the 'child' irqs.
  54 * @pool:               [INTERN] bitmap of irqs currently in use.
  55 * @pool_lock:          [INTERN] protection of the irq pool.
  56 **/
  57struct iio_trigger {
  58        const struct iio_trigger_ops    *ops;
  59        int                             id;
  60        const char                      *name;
  61        struct device                   dev;
  62
  63        struct list_head                list;
  64        struct list_head                alloc_list;
  65        atomic_t                        use_count;
  66
  67        struct irq_chip                 subirq_chip;
  68        int                             subirq_base;
  69
  70        struct iio_subirq subirqs[CONFIG_IIO_CONSUMERS_PER_TRIGGER];
  71        unsigned long pool[BITS_TO_LONGS(CONFIG_IIO_CONSUMERS_PER_TRIGGER)];
  72        struct mutex                    pool_lock;
  73};
  74
  75
  76static inline struct iio_trigger *to_iio_trigger(struct device *d)
  77{
  78        return container_of(d, struct iio_trigger, dev);
  79}
  80
  81static inline void iio_trigger_put(struct iio_trigger *trig)
  82{
  83        module_put(trig->ops->owner);
  84        put_device(&trig->dev);
  85}
  86
  87static inline struct iio_trigger *iio_trigger_get(struct iio_trigger *trig)
  88{
  89        get_device(&trig->dev);
  90        __module_get(trig->ops->owner);
  91
  92        return trig;
  93}
  94
  95/**
  96 * iio_device_set_drvdata() - Set trigger driver data
  97 * @trig: IIO trigger structure
  98 * @data: Driver specific data
  99 *
 100 * Allows to attach an arbitrary pointer to an IIO trigger, which can later be
 101 * retrieved by iio_trigger_get_drvdata().
 102 */
 103static inline void iio_trigger_set_drvdata(struct iio_trigger *trig, void *data)
 104{
 105        dev_set_drvdata(&trig->dev, data);
 106}
 107
 108/**
 109 * iio_trigger_get_drvdata() - Get trigger driver data
 110 * @trig: IIO trigger structure
 111 *
 112 * Returns the data previously set with iio_trigger_set_drvdata()
 113 */
 114static inline void *iio_trigger_get_drvdata(struct iio_trigger *trig)
 115{
 116        return dev_get_drvdata(&trig->dev);
 117}
 118
 119/**
 120 * iio_trigger_register() - register a trigger with the IIO core
 121 * @trig_info:  trigger to be registered
 122 **/
 123int iio_trigger_register(struct iio_trigger *trig_info);
 124
 125/**
 126 * iio_trigger_unregister() - unregister a trigger from the core
 127 * @trig_info:  trigger to be unregistered
 128 **/
 129void iio_trigger_unregister(struct iio_trigger *trig_info);
 130
 131/**
 132 * iio_trigger_poll() - called on a trigger occurring
 133 * @trig:       trigger which occurred
 134 *
 135 * Typically called in relevant hardware interrupt handler.
 136 **/
 137void iio_trigger_poll(struct iio_trigger *trig);
 138void iio_trigger_poll_chained(struct iio_trigger *trig);
 139
 140irqreturn_t iio_trigger_generic_data_rdy_poll(int irq, void *private);
 141
 142__printf(1, 2) struct iio_trigger *iio_trigger_alloc(const char *fmt, ...);
 143void iio_trigger_free(struct iio_trigger *trig);
 144
 145#else
 146struct iio_trigger;
 147struct iio_trigger_ops;
 148#endif
 149#endif /* _IIO_TRIGGER_H_ */
 150