1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * PTP 1588 clock support - private declarations for the core module.
4 *
5 * Copyright (C) 2010 OMICRON electronics GmbH
6 */
7 #ifndef _PTP_PRIVATE_H_
8 #define _PTP_PRIVATE_H_
9
10 #include <linux/cdev.h>
11 #include <linux/device.h>
12 #include <linux/kthread.h>
13 #include <linux/mutex.h>
14 #include <linux/posix-clock.h>
15 #include <linux/ptp_clock.h>
16 #include <linux/ptp_clock_kernel.h>
17 #include <linux/time.h>
18
19 #define PTP_MAX_TIMESTAMPS 128
20 #define PTP_BUF_TIMESTAMPS 30
21 #define PTP_DEFAULT_MAX_VCLOCKS 20
22
23 struct timestamp_event_queue {
24 struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
25 int head;
26 int tail;
27 spinlock_t lock;
28 };
29
30 struct ptp_clock {
31 struct posix_clock clock;
32 struct device dev;
33 struct ptp_clock_info *info;
34 dev_t devid;
35 int index; /* index into clocks.map */
36 struct pps_device *pps_source;
37 long dialed_frequency; /* remembers the frequency adjustment */
38 struct timestamp_event_queue tsevq; /* simple fifo for time stamps */
39 struct mutex tsevq_mux; /* one process at a time reading the fifo */
40 struct mutex pincfg_mux; /* protect concurrent info->pin_config access */
41 wait_queue_head_t tsev_wq;
42 int defunct; /* tells readers to go away when clock is being removed */
43 struct device_attribute *pin_dev_attr;
44 struct attribute **pin_attr;
45 struct attribute_group pin_attr_group;
46 /* 1st entry is a pointer to the real group, 2nd is NULL terminator */
47 const struct attribute_group *pin_attr_groups[2];
48 struct kthread_worker *kworker;
49 struct kthread_delayed_work aux_work;
50 unsigned int max_vclocks;
51 unsigned int n_vclocks;
52 int *vclock_index;
53 struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */
54 bool is_virtual_clock;
55 bool has_cycles;
56 };
57
58 #define info_to_vclock(d) container_of((d), struct ptp_vclock, info)
59 #define cc_to_vclock(d) container_of((d), struct ptp_vclock, cc)
60 #define dw_to_vclock(d) container_of((d), struct ptp_vclock, refresh_work)
61
62 struct ptp_vclock {
63 struct ptp_clock *pclock;
64 struct ptp_clock_info info;
65 struct ptp_clock *clock;
66 struct hlist_node vclock_hash_node;
67 struct cyclecounter cc;
68 struct timecounter tc;
69 spinlock_t lock; /* protects tc/cc */
70 };
71
72 /*
73 * The function queue_cnt() is safe for readers to call without
74 * holding q->lock. Readers use this function to verify that the queue
75 * is nonempty before proceeding with a dequeue operation. The fact
76 * that a writer might concurrently increment the tail does not
77 * matter, since the queue remains nonempty nonetheless.
78 */
queue_cnt(struct timestamp_event_queue * q)79 static inline int queue_cnt(struct timestamp_event_queue *q)
80 {
81 int cnt = q->tail - q->head;
82 return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
83 }
84
85 /* Check if ptp virtual clock is in use */
ptp_vclock_in_use(struct ptp_clock * ptp)86 static inline bool ptp_vclock_in_use(struct ptp_clock *ptp)
87 {
88 bool in_use = false;
89
90 if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
91 return true;
92
93 if (!ptp->is_virtual_clock && ptp->n_vclocks)
94 in_use = true;
95
96 mutex_unlock(&ptp->n_vclocks_mux);
97
98 return in_use;
99 }
100
101 /* Check if ptp clock shall be free running */
ptp_clock_freerun(struct ptp_clock * ptp)102 static inline bool ptp_clock_freerun(struct ptp_clock *ptp)
103 {
104 if (ptp->has_cycles)
105 return false;
106
107 return ptp_vclock_in_use(ptp);
108 }
109
110 extern struct class *ptp_class;
111
112 /*
113 * see ptp_chardev.c
114 */
115
116 /* caller must hold pincfg_mux */
117 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
118 enum ptp_pin_function func, unsigned int chan);
119
120 long ptp_ioctl(struct posix_clock *pc,
121 unsigned int cmd, unsigned long arg);
122
123 int ptp_open(struct posix_clock *pc, fmode_t fmode);
124
125 ssize_t ptp_read(struct posix_clock *pc,
126 uint flags, char __user *buf, size_t cnt);
127
128 __poll_t ptp_poll(struct posix_clock *pc,
129 struct file *fp, poll_table *wait);
130
131 /*
132 * see ptp_sysfs.c
133 */
134
135 extern const struct attribute_group *ptp_groups[];
136
137 int ptp_populate_pin_groups(struct ptp_clock *ptp);
138 void ptp_cleanup_pin_groups(struct ptp_clock *ptp);
139
140 struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock);
141 void ptp_vclock_unregister(struct ptp_vclock *vclock);
142 #endif
143