xref: /linux/drivers/ptp/ptp_private.h (revision 79997eda0d31bc68203c95ecb978773ee6ce7a1f)
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 #include <linux/list.h>
19 #include <linux/bitmap.h>
20 #include <linux/debugfs.h>
21 
22 #define PTP_MAX_TIMESTAMPS 128
23 #define PTP_BUF_TIMESTAMPS 30
24 #define PTP_DEFAULT_MAX_VCLOCKS 20
25 #define PTP_MAX_CHANNELS 2048
26 
27 struct timestamp_event_queue {
28 	struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS];
29 	int head;
30 	int tail;
31 	spinlock_t lock;
32 	struct list_head qlist;
33 	unsigned long *mask;
34 	struct dentry *debugfs_instance;
35 	struct debugfs_u32_array dfs_bitmap;
36 };
37 
38 struct ptp_clock {
39 	struct posix_clock clock;
40 	struct device dev;
41 	struct ptp_clock_info *info;
42 	dev_t devid;
43 	int index; /* index into clocks.map */
44 	struct pps_device *pps_source;
45 	long dialed_frequency; /* remembers the frequency adjustment */
46 	struct list_head tsevqs; /* timestamp fifo list */
47 	spinlock_t tsevqs_lock; /* protects tsevqs from concurrent access */
48 	struct mutex pincfg_mux; /* protect concurrent info->pin_config access */
49 	wait_queue_head_t tsev_wq;
50 	int defunct; /* tells readers to go away when clock is being removed */
51 	struct device_attribute *pin_dev_attr;
52 	struct attribute **pin_attr;
53 	struct attribute_group pin_attr_group;
54 	/* 1st entry is a pointer to the real group, 2nd is NULL terminator */
55 	const struct attribute_group *pin_attr_groups[2];
56 	struct kthread_worker *kworker;
57 	struct kthread_delayed_work aux_work;
58 	unsigned int max_vclocks;
59 	unsigned int n_vclocks;
60 	int *vclock_index;
61 	struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */
62 	bool is_virtual_clock;
63 	bool has_cycles;
64 	struct dentry *debugfs_root;
65 };
66 
67 #define info_to_vclock(d) container_of((d), struct ptp_vclock, info)
68 #define cc_to_vclock(d) container_of((d), struct ptp_vclock, cc)
69 #define dw_to_vclock(d) container_of((d), struct ptp_vclock, refresh_work)
70 
71 struct ptp_vclock {
72 	struct ptp_clock *pclock;
73 	struct ptp_clock_info info;
74 	struct ptp_clock *clock;
75 	struct hlist_node vclock_hash_node;
76 	struct cyclecounter cc;
77 	struct timecounter tc;
78 	struct mutex lock;	/* protects tc/cc */
79 };
80 
81 /*
82  * The function queue_cnt() is safe for readers to call without
83  * holding q->lock. Readers use this function to verify that the queue
84  * is nonempty before proceeding with a dequeue operation. The fact
85  * that a writer might concurrently increment the tail does not
86  * matter, since the queue remains nonempty nonetheless.
87  */
88 static inline int queue_cnt(struct timestamp_event_queue *q)
89 {
90 	int cnt = q->tail - q->head;
91 	return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt;
92 }
93 
94 /* Check if ptp virtual clock is in use */
95 static inline bool ptp_vclock_in_use(struct ptp_clock *ptp)
96 {
97 	bool in_use = false;
98 
99 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
100 		return true;
101 
102 	if (!ptp->is_virtual_clock && ptp->n_vclocks)
103 		in_use = true;
104 
105 	mutex_unlock(&ptp->n_vclocks_mux);
106 
107 	return in_use;
108 }
109 
110 /* Check if ptp clock shall be free running */
111 static inline bool ptp_clock_freerun(struct ptp_clock *ptp)
112 {
113 	if (ptp->has_cycles)
114 		return false;
115 
116 	return ptp_vclock_in_use(ptp);
117 }
118 
119 extern struct class *ptp_class;
120 
121 /*
122  * see ptp_chardev.c
123  */
124 
125 /* caller must hold pincfg_mux */
126 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
127 		    enum ptp_pin_function func, unsigned int chan);
128 
129 long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd,
130 	       unsigned long arg);
131 
132 int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode);
133 
134 int ptp_release(struct posix_clock_context *pccontext);
135 
136 ssize_t ptp_read(struct posix_clock_context *pccontext, uint flags, char __user *buf,
137 		 size_t cnt);
138 
139 __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp,
140 		  poll_table *wait);
141 
142 /*
143  * see ptp_sysfs.c
144  */
145 
146 extern const struct attribute_group *ptp_groups[];
147 
148 int ptp_populate_pin_groups(struct ptp_clock *ptp);
149 void ptp_cleanup_pin_groups(struct ptp_clock *ptp);
150 
151 struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock);
152 void ptp_vclock_unregister(struct ptp_vclock *vclock);
153 #endif
154