tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* The industrial I/O core - character device related
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
10#ifndef _IIO_CHRDEV_H_
11#define _IIO_CHRDEV_H_
12struct iio_dev;
13
14/**
15 * struct iio_handler - Structure used to specify file operations
16 * for a particular chrdev
17 * @chrdev: character device structure
18 * @id: the location in the handler table - used for deallocation.
19 * @flags: file operations related flags including busy flag.
20 * @private: handler specific data used by the fileops registered with
21 * the chrdev.
22 */
23struct iio_handler {
24 struct cdev chrdev;
25 int id;
26 unsigned long flags;
27 void *private;
28};
29
30#define iio_cdev_to_handler(cd) \
31 container_of(cd, struct iio_handler, chrdev)
32
33/**
34 * struct iio_event_data - The actual event being pushed to userspace
35 * @id: event identifier
36 * @timestamp: best estimate of time of event occurrence (often from
37 * the interrupt handler)
38 */
39struct iio_event_data {
40 int id;
41 s64 timestamp;
42};
43
44/**
45 * struct iio_detected_event_list - list element for events that have occurred
46 * @list: linked list header
47 * @ev: the event itself
48 */
49struct iio_detected_event_list {
50 struct list_head list;
51 struct iio_event_data ev;
52};
53
54/**
55 * struct iio_event_interface - chrdev interface for an event line
56 * @dev: device assocated with event interface
57 * @handler: fileoperations and related control for the chrdev
58 * @wait: wait queue to allow blocking reads of events
59 * @event_list_lock: mutex to protect the list of detected events
60 * @det_events: list of detected events
61 * @max_events: maximum number of events before new ones are dropped
62 * @current_events: number of events in detected list
63 */
64struct iio_event_interface {
65 struct device dev;
66 struct iio_handler handler;
67 wait_queue_head_t wait;
68 struct mutex event_list_lock;
69 struct list_head det_events;
70 int max_events;
71 int current_events;
72 struct list_head dev_attr_list;
73};
74
75#endif