xref: /linux/include/linux/ptp_clock_kernel.h (revision d0b73b488c55df905ea8faaad079f8535629ed26)
1 /*
2  * PTP 1588 clock support
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 
21 #ifndef _PTP_CLOCK_KERNEL_H_
22 #define _PTP_CLOCK_KERNEL_H_
23 
24 #include <linux/device.h>
25 #include <linux/pps_kernel.h>
26 #include <linux/ptp_clock.h>
27 
28 
29 struct ptp_clock_request {
30 	enum {
31 		PTP_CLK_REQ_EXTTS,
32 		PTP_CLK_REQ_PEROUT,
33 		PTP_CLK_REQ_PPS,
34 	} type;
35 	union {
36 		struct ptp_extts_request extts;
37 		struct ptp_perout_request perout;
38 	};
39 };
40 
41 /**
42  * struct ptp_clock_info - decribes a PTP hardware clock
43  *
44  * @owner:     The clock driver should set to THIS_MODULE.
45  * @name:      A short "friendly name" to identify the clock and to
46  *             help distinguish PHY based devices from MAC based ones.
47  *             The string is not meant to be a unique id.
48  * @max_adj:   The maximum possible frequency adjustment, in parts per billon.
49  * @n_alarm:   The number of programmable alarms.
50  * @n_ext_ts:  The number of external time stamp channels.
51  * @n_per_out: The number of programmable periodic signals.
52  * @pps:       Indicates whether the clock supports a PPS callback.
53  *
54  * clock operations
55  *
56  * @adjfreq:  Adjusts the frequency of the hardware clock.
57  *            parameter delta: Desired frequency offset from nominal frequency
58  *            in parts per billion
59  *
60  * @adjtime:  Shifts the time of the hardware clock.
61  *            parameter delta: Desired change in nanoseconds.
62  *
63  * @gettime:  Reads the current time from the hardware clock.
64  *            parameter ts: Holds the result.
65  *
66  * @settime:  Set the current time on the hardware clock.
67  *            parameter ts: Time value to set.
68  *
69  * @enable:   Request driver to enable or disable an ancillary feature.
70  *            parameter request: Desired resource to enable or disable.
71  *            parameter on: Caller passes one to enable or zero to disable.
72  *
73  * Drivers should embed their ptp_clock_info within a private
74  * structure, obtaining a reference to it using container_of().
75  *
76  * The callbacks must all return zero on success, non-zero otherwise.
77  */
78 
79 struct ptp_clock_info {
80 	struct module *owner;
81 	char name[16];
82 	s32 max_adj;
83 	int n_alarm;
84 	int n_ext_ts;
85 	int n_per_out;
86 	int pps;
87 	int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
88 	int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
89 	int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts);
90 	int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts);
91 	int (*enable)(struct ptp_clock_info *ptp,
92 		      struct ptp_clock_request *request, int on);
93 };
94 
95 struct ptp_clock;
96 
97 /**
98  * ptp_clock_register() - register a PTP hardware clock driver
99  *
100  * @info:   Structure describing the new clock.
101  * @parent: Pointer to the parent device of the new clock.
102  */
103 
104 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
105 					    struct device *parent);
106 
107 /**
108  * ptp_clock_unregister() - unregister a PTP hardware clock driver
109  *
110  * @ptp:  The clock to remove from service.
111  */
112 
113 extern int ptp_clock_unregister(struct ptp_clock *ptp);
114 
115 
116 enum ptp_clock_events {
117 	PTP_CLOCK_ALARM,
118 	PTP_CLOCK_EXTTS,
119 	PTP_CLOCK_PPS,
120 	PTP_CLOCK_PPSUSR,
121 };
122 
123 /**
124  * struct ptp_clock_event - decribes a PTP hardware clock event
125  *
126  * @type:  One of the ptp_clock_events enumeration values.
127  * @index: Identifies the source of the event.
128  * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
129  * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
130  */
131 
132 struct ptp_clock_event {
133 	int type;
134 	int index;
135 	union {
136 		u64 timestamp;
137 		struct pps_event_time pps_times;
138 	};
139 };
140 
141 /**
142  * ptp_clock_event() - notify the PTP layer about an event
143  *
144  * @ptp:    The clock obtained from ptp_clock_register().
145  * @event:  Message structure describing the event.
146  */
147 
148 extern void ptp_clock_event(struct ptp_clock *ptp,
149 			    struct ptp_clock_event *event);
150 
151 /**
152  * ptp_clock_index() - obtain the device index of a PTP clock
153  *
154  * @ptp:    The clock obtained from ptp_clock_register().
155  */
156 
157 extern int ptp_clock_index(struct ptp_clock *ptp);
158 
159 #endif
160