1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* PTP 1588 clock support - private declarations for the core module.
*
* Copyright (C) 2010 OMICRON electronics GmbH
*/
#ifndef _PTP_PRIVATE_H_
#define _PTP_PRIVATE_H_
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <linux/posix-clock.h>
#include <linux/ptp_clock.h>
#include <linux/ptp_clock_kernel.h>
#include <linux/time.h>
#define PTP_MAX_TIMESTAMPS 128
#define PTP_BUF_TIMESTAMPS 30
struct timestamp_event_queue {
struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
int head;
int tail;
spinlock_t lock;
};
struct ptp_clock {
struct posix_clock clock;
struct device dev;
struct ptp_clock_info *info;
dev_t devid;
int index; /* index into clocks.map */
struct pps_device *pps_source;
long dialed_frequency; /* remembers the frequency adjustment */
struct timestamp_event_queue tsevq; /* simple fifo for time stamps */
struct mutex tsevq_mux; /* one process at a time reading the fifo */
struct mutex pincfg_mux; /* protect concurrent info->pin_config access */
wait_queue_head_t tsev_wq;
int defunct; /* tells readers to go away when clock is being removed */
struct device_attribute *pin_dev_attr;
struct attribute **pin_attr;
struct attribute_group pin_attr_group;
/* 1st entry is a pointer to the real group, 2nd is NULL terminator */
const struct attribute_group *pin_attr_groups[2];
struct kthread_worker *kworker;
struct kthread_delayed_work aux_work;
};
/*
* The function queue_cnt() is safe for readers to call without
* holding q->lock. Readers use this function to verify that the queue
* is nonempty before proceeding with a dequeue operation. The fact
* that a writer might concurrently increment the tail does not
* matter, since the queue remains nonempty nonetheless.
*/
static inline int queue_cnt(const struct timestamp_event_queue *q)
{
/*
* Paired with WRITE_ONCE() in enqueue_external_timestamp(),
* ptp_read(), extts_fifo_show().
*/
int cnt = READ_ONCE(q->tail) - READ_ONCE(q->head);
return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
}
/*
* see ptp_chardev.c
*/
/* caller must hold pincfg_mux */
int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
enum ptp_pin_function func, unsigned int chan);
long ptp_ioctl(struct posix_clock *pc,
unsigned int cmd, unsigned long arg);
int ptp_open(struct posix_clock *pc, fmode_t fmode);
ssize_t ptp_read(struct posix_clock *pc,
uint flags, char __user *buf, size_t cnt);
__poll_t ptp_poll(struct posix_clock *pc,
struct file *fp, poll_table *wait);
/*
* see ptp_sysfs.c
*/
extern const struct attribute_group *ptp_groups[];
int ptp_populate_pin_groups(struct ptp_clock *ptp);
void ptp_cleanup_pin_groups(struct ptp_clock *ptp);
#endif
|
