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
  21struct iio_dev;
  22struct 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 **/
  36struct 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 **/
  63struct 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
  83static inline struct iio_trigger *to_iio_trigger(struct device *d)
  84{
  85        return container_of(d, struct iio_trigger, dev);
  86}
  87
  88static inline void iio_trigger_put(struct iio_trigger *trig)
  89{
  90        module_put(trig->ops->owner);
  91        put_device(&trig->dev);
  92}
  93
  94static 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 */
 110static 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 */
 121static 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 **/
 130int iio_trigger_register(struct iio_trigger *trig_info);
 131
 132int 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 **/
 139void iio_trigger_unregister(struct iio_trigger *trig_info);
 140
 141void 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 **/
 151int 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 **/
 159void iio_trigger_poll(struct iio_trigger *trig);
 160void iio_trigger_poll_chained(struct iio_trigger *trig);
 161
 162irqreturn_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, ...);
 165void 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 */
 171bool iio_trigger_using_own(struct iio_dev *indio_dev);
 172
 173int iio_trigger_validate_own_device(struct iio_trigger *trig,
 174                                     struct iio_dev *indio_dev);
 175
 176#else
 177struct iio_trigger;
 178struct iio_trigger_ops;
 179#endif
 180#endif /* _IIO_TRIGGER_H_ */
 181