xref: /OK3568_Linux_fs/kernel/include/linux/gnss.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * GNSS receiver support
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Copyright (C) 2018 Johan Hovold <johan@kernel.org>
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #ifndef _LINUX_GNSS_H
9*4882a593Smuzhiyun #define _LINUX_GNSS_H
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <linux/cdev.h>
12*4882a593Smuzhiyun #include <linux/device.h>
13*4882a593Smuzhiyun #include <linux/kfifo.h>
14*4882a593Smuzhiyun #include <linux/mutex.h>
15*4882a593Smuzhiyun #include <linux/rwsem.h>
16*4882a593Smuzhiyun #include <linux/types.h>
17*4882a593Smuzhiyun #include <linux/wait.h>
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun struct gnss_device;
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun enum gnss_type {
22*4882a593Smuzhiyun 	GNSS_TYPE_NMEA = 0,
23*4882a593Smuzhiyun 	GNSS_TYPE_SIRF,
24*4882a593Smuzhiyun 	GNSS_TYPE_UBX,
25*4882a593Smuzhiyun 	GNSS_TYPE_MTK,
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun 	GNSS_TYPE_COUNT
28*4882a593Smuzhiyun };
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun struct gnss_operations {
31*4882a593Smuzhiyun 	int (*open)(struct gnss_device *gdev);
32*4882a593Smuzhiyun 	void (*close)(struct gnss_device *gdev);
33*4882a593Smuzhiyun 	int (*write_raw)(struct gnss_device *gdev, const unsigned char *buf,
34*4882a593Smuzhiyun 				size_t count);
35*4882a593Smuzhiyun };
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun struct gnss_device {
38*4882a593Smuzhiyun 	struct device dev;
39*4882a593Smuzhiyun 	struct cdev cdev;
40*4882a593Smuzhiyun 	int id;
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun 	enum gnss_type type;
43*4882a593Smuzhiyun 	unsigned long flags;
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun 	struct rw_semaphore rwsem;
46*4882a593Smuzhiyun 	const struct gnss_operations *ops;
47*4882a593Smuzhiyun 	unsigned int count;
48*4882a593Smuzhiyun 	unsigned int disconnected:1;
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 	struct mutex read_mutex;
51*4882a593Smuzhiyun 	struct kfifo read_fifo;
52*4882a593Smuzhiyun 	wait_queue_head_t read_queue;
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	struct mutex write_mutex;
55*4882a593Smuzhiyun 	char *write_buf;
56*4882a593Smuzhiyun };
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun struct gnss_device *gnss_allocate_device(struct device *parent);
59*4882a593Smuzhiyun void gnss_put_device(struct gnss_device *gdev);
60*4882a593Smuzhiyun int gnss_register_device(struct gnss_device *gdev);
61*4882a593Smuzhiyun void gnss_deregister_device(struct gnss_device *gdev);
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun int gnss_insert_raw(struct gnss_device *gdev, const unsigned char *buf,
64*4882a593Smuzhiyun 			size_t count);
65*4882a593Smuzhiyun 
gnss_set_drvdata(struct gnss_device * gdev,void * data)66*4882a593Smuzhiyun static inline void gnss_set_drvdata(struct gnss_device *gdev, void *data)
67*4882a593Smuzhiyun {
68*4882a593Smuzhiyun 	dev_set_drvdata(&gdev->dev, data);
69*4882a593Smuzhiyun }
70*4882a593Smuzhiyun 
gnss_get_drvdata(struct gnss_device * gdev)71*4882a593Smuzhiyun static inline void *gnss_get_drvdata(struct gnss_device *gdev)
72*4882a593Smuzhiyun {
73*4882a593Smuzhiyun 	return dev_get_drvdata(&gdev->dev);
74*4882a593Smuzhiyun }
75*4882a593Smuzhiyun 
76*4882a593Smuzhiyun #endif /* _LINUX_GNSS_H */
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