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(const struct timestamp_event_queue *q) |
89 | { |
90 | /* |
91 | * Paired with WRITE_ONCE() in enqueue_external_timestamp(), |
92 | * ptp_read(), extts_fifo_show(). |
93 | */ |
94 | int cnt = READ_ONCE(q->tail) - READ_ONCE(q->head); |
95 | return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt; |
96 | } |
97 | |
98 | /* Check if ptp virtual clock is in use */ |
99 | static inline bool ptp_vclock_in_use(struct ptp_clock *ptp) |
100 | { |
101 | bool in_use = false; |
102 | |
103 | if (mutex_lock_interruptible(&ptp->n_vclocks_mux)) |
104 | return true; |
105 | |
106 | if (!ptp->is_virtual_clock && ptp->n_vclocks) |
107 | in_use = true; |
108 | |
109 | mutex_unlock(lock: &ptp->n_vclocks_mux); |
110 | |
111 | return in_use; |
112 | } |
113 | |
114 | /* Check if ptp clock shall be free running */ |
115 | static inline bool ptp_clock_freerun(struct ptp_clock *ptp) |
116 | { |
117 | if (ptp->has_cycles) |
118 | return false; |
119 | |
120 | return ptp_vclock_in_use(ptp); |
121 | } |
122 | |
123 | extern const struct class ptp_class; |
124 | |
125 | /* |
126 | * see ptp_chardev.c |
127 | */ |
128 | |
129 | /* caller must hold pincfg_mux */ |
130 | int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin, |
131 | enum ptp_pin_function func, unsigned int chan); |
132 | |
133 | long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd, |
134 | unsigned long arg); |
135 | |
136 | int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode); |
137 | |
138 | int ptp_release(struct posix_clock_context *pccontext); |
139 | |
140 | ssize_t ptp_read(struct posix_clock_context *pccontext, uint flags, char __user *buf, |
141 | size_t cnt); |
142 | |
143 | __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp, |
144 | poll_table *wait); |
145 | |
146 | /* |
147 | * see ptp_sysfs.c |
148 | */ |
149 | |
150 | extern const struct attribute_group *ptp_groups[]; |
151 | |
152 | int ptp_populate_pin_groups(struct ptp_clock *ptp); |
153 | void ptp_cleanup_pin_groups(struct ptp_clock *ptp); |
154 | |
155 | struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock); |
156 | void ptp_vclock_unregister(struct ptp_vclock *vclock); |
157 | #endif |
158 | |