include/linux/iio/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
  14 struct iio_subirq {
  15         bool enabled;
  16 };
  17
  18 struct iio_dev;
  19 struct 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  **/
  32 struct 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  **/
  60 struct 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
  82 static inline struct iio_trigger *to_iio_trigger(struct device *d)
  83 {
  84         return container_of(d, struct iio_trigger, dev);
  85 }
  86
  87 static inline void iio_trigger_put(struct iio_trigger *trig)
  88 {
  89         module_put(trig->owner);
  90         put_device(&trig->dev);
  91 }
  92
  93 static 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  */
 114 static 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  */
 125 static 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  **/
 134 int iio_trigger_register(struct iio_trigger *trig_info);
 135
 136 int 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  **/
 143 void 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  **/
 152 int iio_trigger_set_immutable(struct iio_dev *indio_dev, struct iio_trigger *trig);
 153
 154 void iio_trigger_poll(struct iio_trigger *trig);
 155 void iio_trigger_poll_nested(struct iio_trigger *trig);
 156
 157 irqreturn_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)
 163 struct iio_trigger *__iio_trigger_alloc(struct device *parent,
 164                                         struct module *this_mod,
 165                                         const char *fmt, ...);
 166 void 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  */
 172 bool iio_trigger_using_own(struct iio_dev *indio_dev);
 173
 174 int iio_validate_own_trigger(struct iio_dev *idev, struct iio_trigger *trig);
 175 int iio_trigger_validate_own_device(struct iio_trigger *trig,
 176                                      struct iio_dev *indio_dev);
 177
 178 #else
 179 struct iio_trigger;
 180 struct iio_trigger_ops;
 181 #endif
 182 #endif /* _IIO_TRIGGER_H_ */