xref: /OK3568_Linux_fs/kernel/include/linux/pps_kernel.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-or-later */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * PPS API kernel header
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Copyright (C) 2009   Rodolfo Giometti <giometti@linux.it>
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #ifndef LINUX_PPS_KERNEL_H
9*4882a593Smuzhiyun #define LINUX_PPS_KERNEL_H
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <linux/pps.h>
12*4882a593Smuzhiyun #include <linux/cdev.h>
13*4882a593Smuzhiyun #include <linux/device.h>
14*4882a593Smuzhiyun #include <linux/time.h>
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun /*
17*4882a593Smuzhiyun  * Global defines
18*4882a593Smuzhiyun  */
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun struct pps_device;
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun /* The specific PPS source info */
23*4882a593Smuzhiyun struct pps_source_info {
24*4882a593Smuzhiyun 	char name[PPS_MAX_NAME_LEN];		/* symbolic name */
25*4882a593Smuzhiyun 	char path[PPS_MAX_NAME_LEN];		/* path of connected device */
26*4882a593Smuzhiyun 	int mode;				/* PPS allowed mode */
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 	void (*echo)(struct pps_device *pps,
29*4882a593Smuzhiyun 			int event, void *data);	/* PPS echo function */
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun 	struct module *owner;
32*4882a593Smuzhiyun 	struct device *dev;		/* Parent device for device_create */
33*4882a593Smuzhiyun };
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun struct pps_event_time {
36*4882a593Smuzhiyun #ifdef CONFIG_NTP_PPS
37*4882a593Smuzhiyun 	struct timespec64 ts_raw;
38*4882a593Smuzhiyun #endif /* CONFIG_NTP_PPS */
39*4882a593Smuzhiyun 	struct timespec64 ts_real;
40*4882a593Smuzhiyun };
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun /* The main struct */
43*4882a593Smuzhiyun struct pps_device {
44*4882a593Smuzhiyun 	struct pps_source_info info;		/* PSS source info */
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	struct pps_kparams params;		/* PPS current params */
47*4882a593Smuzhiyun 
48*4882a593Smuzhiyun 	__u32 assert_sequence;			/* PPS assert event seq # */
49*4882a593Smuzhiyun 	__u32 clear_sequence;			/* PPS clear event seq # */
50*4882a593Smuzhiyun 	struct pps_ktime assert_tu;
51*4882a593Smuzhiyun 	struct pps_ktime clear_tu;
52*4882a593Smuzhiyun 	int current_mode;			/* PPS mode at event time */
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	unsigned int last_ev;			/* last PPS event id */
55*4882a593Smuzhiyun 	wait_queue_head_t queue;		/* PPS event queue */
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun 	unsigned int id;			/* PPS source unique ID */
58*4882a593Smuzhiyun 	void const *lookup_cookie;		/* For pps_lookup_dev() only */
59*4882a593Smuzhiyun 	struct cdev cdev;
60*4882a593Smuzhiyun 	struct device *dev;
61*4882a593Smuzhiyun 	struct fasync_struct *async_queue;	/* fasync method */
62*4882a593Smuzhiyun 	spinlock_t lock;
63*4882a593Smuzhiyun };
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun /*
66*4882a593Smuzhiyun  * Global variables
67*4882a593Smuzhiyun  */
68*4882a593Smuzhiyun 
69*4882a593Smuzhiyun extern const struct attribute_group *pps_groups[];
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun /*
72*4882a593Smuzhiyun  * Internal functions.
73*4882a593Smuzhiyun  *
74*4882a593Smuzhiyun  * These are not actually part of the exported API, but this is a
75*4882a593Smuzhiyun  * convenient header file to put them in.
76*4882a593Smuzhiyun  */
77*4882a593Smuzhiyun 
78*4882a593Smuzhiyun extern int pps_register_cdev(struct pps_device *pps);
79*4882a593Smuzhiyun extern void pps_unregister_cdev(struct pps_device *pps);
80*4882a593Smuzhiyun 
81*4882a593Smuzhiyun /*
82*4882a593Smuzhiyun  * Exported functions
83*4882a593Smuzhiyun  */
84*4882a593Smuzhiyun 
85*4882a593Smuzhiyun extern struct pps_device *pps_register_source(
86*4882a593Smuzhiyun 		struct pps_source_info *info, int default_params);
87*4882a593Smuzhiyun extern void pps_unregister_source(struct pps_device *pps);
88*4882a593Smuzhiyun extern void pps_event(struct pps_device *pps,
89*4882a593Smuzhiyun 		struct pps_event_time *ts, int event, void *data);
90*4882a593Smuzhiyun /* Look up a pps_device by magic cookie */
91*4882a593Smuzhiyun struct pps_device *pps_lookup_dev(void const *cookie);
92*4882a593Smuzhiyun 
timespec_to_pps_ktime(struct pps_ktime * kt,struct timespec64 ts)93*4882a593Smuzhiyun static inline void timespec_to_pps_ktime(struct pps_ktime *kt,
94*4882a593Smuzhiyun 		struct timespec64 ts)
95*4882a593Smuzhiyun {
96*4882a593Smuzhiyun 	kt->sec = ts.tv_sec;
97*4882a593Smuzhiyun 	kt->nsec = ts.tv_nsec;
98*4882a593Smuzhiyun }
99*4882a593Smuzhiyun 
pps_get_ts(struct pps_event_time * ts)100*4882a593Smuzhiyun static inline void pps_get_ts(struct pps_event_time *ts)
101*4882a593Smuzhiyun {
102*4882a593Smuzhiyun 	struct system_time_snapshot snap;
103*4882a593Smuzhiyun 
104*4882a593Smuzhiyun 	ktime_get_snapshot(&snap);
105*4882a593Smuzhiyun 	ts->ts_real = ktime_to_timespec64(snap.real);
106*4882a593Smuzhiyun #ifdef CONFIG_NTP_PPS
107*4882a593Smuzhiyun 	ts->ts_raw = ktime_to_timespec64(snap.raw);
108*4882a593Smuzhiyun #endif
109*4882a593Smuzhiyun }
110*4882a593Smuzhiyun 
111*4882a593Smuzhiyun /* Subtract known time delay from PPS event time(s) */
pps_sub_ts(struct pps_event_time * ts,struct timespec64 delta)112*4882a593Smuzhiyun static inline void pps_sub_ts(struct pps_event_time *ts, struct timespec64 delta)
113*4882a593Smuzhiyun {
114*4882a593Smuzhiyun 	ts->ts_real = timespec64_sub(ts->ts_real, delta);
115*4882a593Smuzhiyun #ifdef CONFIG_NTP_PPS
116*4882a593Smuzhiyun 	ts->ts_raw = timespec64_sub(ts->ts_raw, delta);
117*4882a593Smuzhiyun #endif
118*4882a593Smuzhiyun }
119*4882a593Smuzhiyun 
120*4882a593Smuzhiyun #endif /* LINUX_PPS_KERNEL_H */
121