xref: /linux/drivers/iio/industrialio-triggered-event.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  * Copyright (C) 2015 Cogent Embedded, Inc.
3  *
4  * This program is free software; you can redistribute  it and/or modify it
5  * under  the terms of  the GNU General  Public License as published by the
6  * Free Software Foundation;  either version 2 of the  License, or (at your
7  * option) any later version.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/export.h>
12 #include <linux/module.h>
13 #include <linux/iio/iio.h>
14 #include <linux/iio/triggered_event.h>
15 #include <linux/iio/trigger_consumer.h>
16 
17 /**
18  * iio_triggered_event_setup() - Setup pollfunc_event for triggered event
19  * @indio_dev:	IIO device structure
20  * @h:		Function which will be used as pollfunc_event top half
21  * @thread:	Function which will be used as pollfunc_event bottom half
22  *
23  * This function combines some common tasks which will normally be performed
24  * when setting up a triggered event. It will allocate the pollfunc_event and
25  * set mode to use it for triggered event.
26  *
27  * Before calling this function the indio_dev structure should already be
28  * completely initialized, but not yet registered. In practice this means that
29  * this function should be called right before iio_device_register().
30  *
31  * To free the resources allocated by this function call
32  * iio_triggered_event_cleanup().
33  */
34 int iio_triggered_event_setup(struct iio_dev *indio_dev,
35 			      irqreturn_t (*h)(int irq, void *p),
36 			      irqreturn_t (*thread)(int irq, void *p))
37 {
38 	indio_dev->pollfunc_event = iio_alloc_pollfunc(h,
39 						       thread,
40 						       IRQF_ONESHOT,
41 						       indio_dev,
42 						       "%s_consumer%d",
43 						       indio_dev->name,
44 						       indio_dev->id);
45 	if (indio_dev->pollfunc_event == NULL)
46 		return -ENOMEM;
47 
48 	/* Flag that events polling is possible */
49 	indio_dev->modes |= INDIO_EVENT_TRIGGERED;
50 
51 	return 0;
52 }
53 EXPORT_SYMBOL(iio_triggered_event_setup);
54 
55 /**
56  * iio_triggered_event_cleanup() - Free resources allocated by iio_triggered_event_setup()
57  * @indio_dev: IIO device structure
58  */
59 void iio_triggered_event_cleanup(struct iio_dev *indio_dev)
60 {
61 	indio_dev->modes &= ~INDIO_EVENT_TRIGGERED;
62 	iio_dealloc_pollfunc(indio_dev->pollfunc_event);
63 }
64 EXPORT_SYMBOL(iio_triggered_event_cleanup);
65 
66 MODULE_AUTHOR("Vladimir Barinov");
67 MODULE_DESCRIPTION("IIO helper functions for setting up triggered events");
68 MODULE_LICENSE("GPL");
69