drivers/iio/industrialio-triggered-event.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2015 Cogent Embedded, Inc.
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/export.h>
   8 #include <linux/module.h>
   9 #include <linux/iio/iio.h>
  10 #include <linux/iio/triggered_event.h>
  11 #include <linux/iio/trigger_consumer.h>
  12
  13 /**
  14  * iio_triggered_event_setup() - Setup pollfunc_event for triggered event
  15  * @indio_dev:  IIO device structure
  16  * @h:          Function which will be used as pollfunc_event top half
  17  * @thread:     Function which will be used as pollfunc_event bottom half
  18  *
  19  * This function combines some common tasks which will normally be performed
  20  * when setting up a triggered event. It will allocate the pollfunc_event and
  21  * set mode to use it for triggered event.
  22  *
  23  * Before calling this function the indio_dev structure should already be
  24  * completely initialized, but not yet registered. In practice this means that
  25  * this function should be called right before iio_device_register().
  26  *
  27  * To free the resources allocated by this function call
  28  * iio_triggered_event_cleanup().
  29  */
  30 int iio_triggered_event_setup(struct iio_dev *indio_dev,
  31                               irqreturn_t (*h)(int irq, void *p),
  32                               irqreturn_t (*thread)(int irq, void *p))
  33 {
  34         indio_dev->pollfunc_event = iio_alloc_pollfunc(h,
  35                                                        thread,
  36                                                        IRQF_ONESHOT,
  37                                                        indio_dev,
  38                                                        "%s_consumer%d",
  39                                                        indio_dev->name,
  40                                                        indio_dev->id);
  41         if (indio_dev->pollfunc_event == NULL)
  42                 return -ENOMEM;
  43
  44         /* Flag that events polling is possible */
  45         indio_dev->modes |= INDIO_EVENT_TRIGGERED;
  46
  47         return 0;
  48 }
  49 EXPORT_SYMBOL(iio_triggered_event_setup);
  50
  51 /**
  52  * iio_triggered_event_cleanup() - Free resources allocated by iio_triggered_event_setup()
  53  * @indio_dev: IIO device structure
  54  */
  55 void iio_triggered_event_cleanup(struct iio_dev *indio_dev)
  56 {
  57         indio_dev->modes &= ~INDIO_EVENT_TRIGGERED;
  58         iio_dealloc_pollfunc(indio_dev->pollfunc_event);
  59 }
  60 EXPORT_SYMBOL(iio_triggered_event_cleanup);
  61
  62 MODULE_AUTHOR("Vladimir Barinov");
  63 MODULE_DESCRIPTION("IIO helper functions for setting up triggered events");
  64 MODULE_LICENSE("GPL");