1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * GNSS receiver support
4 *
5 * Copyright (C) 2018 Johan Hovold <johan@kernel.org>
6 */
7
8 #ifndef _LINUX_GNSS_H
9 #define _LINUX_GNSS_H
10
11 #include <linux/cdev.h>
12 #include <linux/device.h>
13 #include <linux/kfifo.h>
14 #include <linux/mutex.h>
15 #include <linux/rwsem.h>
16 #include <linux/types.h>
17 #include <linux/wait.h>
18
19 struct gnss_device;
20
21 enum gnss_type {
22 GNSS_TYPE_NMEA = 0,
23 GNSS_TYPE_SIRF,
24 GNSS_TYPE_UBX,
25 GNSS_TYPE_MTK,
26
27 GNSS_TYPE_COUNT
28 };
29
30 struct gnss_operations {
31 int (*open)(struct gnss_device *gdev);
32 void (*close)(struct gnss_device *gdev);
33 int (*write_raw)(struct gnss_device *gdev, const unsigned char *buf,
34 size_t count);
35 };
36
37 struct gnss_device {
38 struct device dev;
39 struct cdev cdev;
40 int id;
41
42 enum gnss_type type;
43 unsigned long flags;
44
45 struct rw_semaphore rwsem;
46 const struct gnss_operations *ops;
47 unsigned int count;
48 unsigned int disconnected:1;
49
50 struct mutex read_mutex;
51 struct kfifo read_fifo;
52 wait_queue_head_t read_queue;
53
54 struct mutex write_mutex;
55 char *write_buf;
56 };
57
58 struct gnss_device *gnss_allocate_device(struct device *parent);
59 void gnss_put_device(struct gnss_device *gdev);
60 int gnss_register_device(struct gnss_device *gdev);
61 void gnss_deregister_device(struct gnss_device *gdev);
62
63 int gnss_insert_raw(struct gnss_device *gdev, const unsigned char *buf,
64 size_t count);
65
gnss_set_drvdata(struct gnss_device * gdev,void * data)66 static inline void gnss_set_drvdata(struct gnss_device *gdev, void *data)
67 {
68 dev_set_drvdata(&gdev->dev, data);
69 }
70
gnss_get_drvdata(struct gnss_device * gdev)71 static inline void *gnss_get_drvdata(struct gnss_device *gdev)
72 {
73 return dev_get_drvdata(&gdev->dev);
74 }
75
76 #endif /* _LINUX_GNSS_H */
77