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/ptp_clock.h>
25 
26 
27 struct ptp_clock_request {
28 	enum {
29 		PTP_CLK_REQ_EXTTS,
30 		PTP_CLK_REQ_PEROUT,
31 		PTP_CLK_REQ_PPS,
32 	} type;
33 	union {
34 		struct ptp_extts_request extts;
35 		struct ptp_perout_request perout;
36 	};
37 };
38 
39 /**
40  * struct ptp_clock_info - decribes a PTP hardware clock
41  *
42  * @owner:     The clock driver should set to THIS_MODULE.
43  * @name:      A short name to identify the clock.
44  * @max_adj:   The maximum possible frequency adjustment, in parts per billon.
45  * @n_alarm:   The number of programmable alarms.
46  * @n_ext_ts:  The number of external time stamp channels.
47  * @n_per_out: The number of programmable periodic signals.
48  * @pps:       Indicates whether the clock supports a PPS callback.
49  *
50  * clock operations
51  *
52  * @adjfreq:  Adjusts the frequency of the hardware clock.
53  *            parameter delta: Desired period change in parts per billion.
54  *
55  * @adjtime:  Shifts the time of the hardware clock.
56  *            parameter delta: Desired change in nanoseconds.
57  *
58  * @gettime:  Reads the current time from the hardware clock.
59  *            parameter ts: Holds the result.
60  *
61  * @settime:  Set the current time on the hardware clock.
62  *            parameter ts: Time value to set.
63  *
64  * @enable:   Request driver to enable or disable an ancillary feature.
65  *            parameter request: Desired resource to enable or disable.
66  *            parameter on: Caller passes one to enable or zero to disable.
67  *
68  * Drivers should embed their ptp_clock_info within a private
69  * structure, obtaining a reference to it using container_of().
70  *
71  * The callbacks must all return zero on success, non-zero otherwise.
72  */
73 
74 struct ptp_clock_info {
75 	struct module *owner;
76 	char name[16];
77 	s32 max_adj;
78 	int n_alarm;
79 	int n_ext_ts;
80 	int n_per_out;
81 	int pps;
82 	int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
83 	int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
84 	int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts);
85 	int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts);
86 	int (*enable)(struct ptp_clock_info *ptp,
87 		      struct ptp_clock_request *request, int on);
88 };
89 
90 struct ptp_clock;
91 
92 /**
93  * ptp_clock_register() - register a PTP hardware clock driver
94  *
95  * @info:  Structure describing the new clock.
96  */
97 
98 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info);
99 
100 /**
101  * ptp_clock_unregister() - unregister a PTP hardware clock driver
102  *
103  * @ptp:  The clock to remove from service.
104  */
105 
106 extern int ptp_clock_unregister(struct ptp_clock *ptp);
107 
108 
109 enum ptp_clock_events {
110 	PTP_CLOCK_ALARM,
111 	PTP_CLOCK_EXTTS,
112 	PTP_CLOCK_PPS,
113 };
114 
115 /**
116  * struct ptp_clock_event - decribes a PTP hardware clock event
117  *
118  * @type:  One of the ptp_clock_events enumeration values.
119  * @index: Identifies the source of the event.
120  * @timestamp: When the event occured.
121  */
122 
123 struct ptp_clock_event {
124 	int type;
125 	int index;
126 	u64 timestamp;
127 };
128 
129 /**
130  * ptp_clock_event() - notify the PTP layer about an event
131  *
132  * @ptp:    The clock obtained from ptp_clock_register().
133  * @event:  Message structure describing the event.
134  */
135 
136 extern void ptp_clock_event(struct ptp_clock *ptp,
137 			    struct ptp_clock_event *event);
138 
139 #endif
140