Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
pps.h
Go to the documentation of this file.
1 /*
2  * PPS API header
3  *
4  * Copyright (C) 2005-2009 Rodolfo Giometti <[email protected]>
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 
22 #ifndef _PPS_H_
23 #define _PPS_H_
24 
25 #include <linux/types.h>
26 
27 #define PPS_VERSION "5.3.6"
28 #define PPS_MAX_SOURCES 16 /* should be enough... */
29 
30 /* Implementation note: the logical states ``assert'' and ``clear''
31  * are implemented in terms of the chip register, i.e. ``assert''
32  * means the bit is set. */
33 
34 /*
35  * 3.2 New data structures
36  */
37 
38 #define PPS_API_VERS_1 1
39 #define PPS_API_VERS PPS_API_VERS_1 /* we use API version 1 */
40 #define PPS_MAX_NAME_LEN 32
41 
42 /* 32-bit vs. 64-bit compatibility.
43  *
44  * 0n i386, the alignment of a uint64_t is only 4 bytes, while on most other
45  * architectures it's 8 bytes. On i386, there will be no padding between the
46  * two consecutive 'struct pps_ktime' members of struct pps_kinfo and struct
47  * pps_kparams. But on most platforms there will be padding to ensure correct
48  * alignment.
49  *
50  * The simple fix is probably to add an explicit padding.
51  * [David Woodhouse]
52  */
53 struct pps_ktime {
57 };
58 #define PPS_TIME_INVALID (1<<0) /* used to specify timeout==NULL */
59 
60 struct pps_kinfo {
61  __u32 assert_sequence; /* seq. num. of assert event */
62  __u32 clear_sequence; /* seq. num. of clear event */
63  struct pps_ktime assert_tu; /* time of assert event */
64  struct pps_ktime clear_tu; /* time of clear event */
65  int current_mode; /* current mode bits */
66 };
67 
68 struct pps_kparams {
69  int api_version; /* API version # */
70  int mode; /* mode bits */
71  struct pps_ktime assert_off_tu; /* offset compensation for assert */
72  struct pps_ktime clear_off_tu; /* offset compensation for clear */
73 };
74 
75 /*
76  * 3.3 Mode bit definitions
77  */
78 
79 /* Device/implementation parameters */
80 #define PPS_CAPTUREASSERT 0x01 /* capture assert events */
81 #define PPS_CAPTURECLEAR 0x02 /* capture clear events */
82 #define PPS_CAPTUREBOTH 0x03 /* capture assert and clear events */
83 
84 #define PPS_OFFSETASSERT 0x10 /* apply compensation for assert ev. */
85 #define PPS_OFFSETCLEAR 0x20 /* apply compensation for clear ev. */
86 
87 #define PPS_CANWAIT 0x100 /* can we wait for an event? */
88 #define PPS_CANPOLL 0x200 /* bit reserved for future use */
89 
90 /* Kernel actions */
91 #define PPS_ECHOASSERT 0x40 /* feed back assert event to output */
92 #define PPS_ECHOCLEAR 0x80 /* feed back clear event to output */
93 
94 /* Timestamp formats */
95 #define PPS_TSFMT_TSPEC 0x1000 /* select timespec format */
96 #define PPS_TSFMT_NTPFP 0x2000 /* select NTP format */
97 
98 /*
99  * 3.4.4 New functions: disciplining the kernel timebase
100  */
101 
102 /* Kernel consumers */
103 #define PPS_KC_HARDPPS 0 /* hardpps() (or equivalent) */
104 #define PPS_KC_HARDPPS_PLL 1 /* hardpps() constrained to
105  use a phase-locked loop */
106 #define PPS_KC_HARDPPS_FLL 2 /* hardpps() constrained to
107  use a frequency-locked loop */
108 /*
109  * Here begins the implementation-specific part!
110  */
112 struct pps_fdata {
113  struct pps_kinfo info;
114  struct pps_ktime timeout;
115 };
118  int tsformat; /* format of time stamps */
119  int edge; /* selected event type */
120  int consumer; /* selected kernel consumer */
121 };
122 
123 #include <linux/ioctl.h>
125 #define PPS_GETPARAMS _IOR('p', 0xa1, struct pps_kparams *)
126 #define PPS_SETPARAMS _IOW('p', 0xa2, struct pps_kparams *)
127 #define PPS_GETCAP _IOR('p', 0xa3, int *)
128 #define PPS_FETCH _IOWR('p', 0xa4, struct pps_fdata *)
129 #define PPS_KC_BIND _IOW('p', 0xa5, struct pps_bind_args *)
130 
131 #endif /* _PPS_H_ */