1/*
2 * PTP 1588 clock support - private declarations for the core module.
3 *
4 * Copyright (C) 2010 OMICRON electronics GmbH
5 *
6 *  This program is free software; you can redistribute it and/or modify
7 *  it under the terms of the GNU General Public License as published by
8 *  the Free Software Foundation; either version 2 of the License, or
9 *  (at your option) any later version.
10 *
11 *  This program is distributed in the hope that it will be useful,
12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 *  GNU General Public License for more details.
15 *
16 *  You should have received a copy of the GNU General Public License
17 *  along with this program; if not, write to the Free Software
18 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20#ifndef _PTP_PRIVATE_H_
21#define _PTP_PRIVATE_H_
22
23#include <linux/cdev.h>
24#include <linux/device.h>
25#include <linux/mutex.h>
26#include <linux/posix-clock.h>
27#include <linux/ptp_clock.h>
28#include <linux/ptp_clock_kernel.h>
29#include <linux/time.h>
30
31#define PTP_MAX_TIMESTAMPS 128
32#define PTP_BUF_TIMESTAMPS 30
33
34struct timestamp_event_queue {
35	struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
36	int head;
37	int tail;
38	spinlock_t lock;
39};
40
41struct ptp_clock {
42	struct posix_clock clock;
43	struct device *dev;
44	struct ptp_clock_info *info;
45	dev_t devid;
46	int index; /* index into clocks.map */
47	struct pps_device *pps_source;
48	long dialed_frequency; /* remembers the frequency adjustment */
49	struct timestamp_event_queue tsevq; /* simple fifo for time stamps */
50	struct mutex tsevq_mux; /* one process at a time reading the fifo */
51	struct mutex pincfg_mux; /* protect concurrent info->pin_config access */
52	wait_queue_head_t tsev_wq;
53	int defunct; /* tells readers to go away when clock is being removed */
54	struct device_attribute *pin_dev_attr;
55	struct attribute **pin_attr;
56	struct attribute_group pin_attr_group;
57};
58
59/*
60 * The function queue_cnt() is safe for readers to call without
61 * holding q->lock. Readers use this function to verify that the queue
62 * is nonempty before proceeding with a dequeue operation. The fact
63 * that a writer might concurrently increment the tail does not
64 * matter, since the queue remains nonempty nonetheless.
65 */
66static inline int queue_cnt(struct timestamp_event_queue *q)
67{
68	int cnt = q->tail - q->head;
69	return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
70}
71
72/*
73 * see ptp_chardev.c
74 */
75
76/* caller must hold pincfg_mux */
77int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
78		    enum ptp_pin_function func, unsigned int chan);
79
80long ptp_ioctl(struct posix_clock *pc,
81	       unsigned int cmd, unsigned long arg);
82
83int ptp_open(struct posix_clock *pc, fmode_t fmode);
84
85ssize_t ptp_read(struct posix_clock *pc,
86		 uint flags, char __user *buf, size_t cnt);
87
88uint ptp_poll(struct posix_clock *pc,
89	      struct file *fp, poll_table *wait);
90
91/*
92 * see ptp_sysfs.c
93 */
94
95extern const struct attribute_group *ptp_groups[];
96
97int ptp_cleanup_sysfs(struct ptp_clock *ptp);
98
99int ptp_populate_sysfs(struct ptp_clock *ptp);
100
101#endif
102