linux-headers/linux/pps.h
2023-06-07 11:35:51 +00:00

152 lines
4.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
/*
* PPS API header
*
* Copyright (C) 2005-2009 Rodolfo Giometti <giometti@linux.it>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef _PPS_H_
#define _PPS_H_
#include <linux/types.h>
#define PPS_VERSION "5.3.6"
#define PPS_MAX_SOURCES 16 /* should be enough... */
/* Implementation note: the logical states ``assert'' and ``clear''
* are implemented in terms of the chip register, i.e. ``assert''
* means the bit is set. */
/*
* 3.2 New data structures
*/
#define PPS_API_VERS_1 1
#define PPS_API_VERS PPS_API_VERS_1 /* we use API version 1 */
#define PPS_MAX_NAME_LEN 32
/* 32-bit vs. 64-bit compatibility.
*
* 0n i386, the alignment of a uint64_t is only 4 bytes, while on most other
* architectures it's 8 bytes. On i386, there will be no padding between the
* two consecutive 'struct pps_ktime' members of struct pps_kinfo and struct
* pps_kparams. But on most platforms there will be padding to ensure correct
* alignment.
*
* The simple fix is probably to add an explicit padding.
* [David Woodhouse]
*/
struct pps_ktime {
__s64 sec;
__s32 nsec;
__u32 flags;
};
struct pps_ktime_compat {
__s64 sec;
__s32 nsec;
__u32 flags;
} __attribute__((packed, aligned(4)));
#define PPS_TIME_INVALID (1<<0) /* used to specify timeout==NULL */
struct pps_kinfo {
__u32 assert_sequence; /* seq. num. of assert event */
__u32 clear_sequence; /* seq. num. of clear event */
struct pps_ktime assert_tu; /* time of assert event */
struct pps_ktime clear_tu; /* time of clear event */
int current_mode; /* current mode bits */
};
struct pps_kinfo_compat {
__u32 assert_sequence; /* seq. num. of assert event */
__u32 clear_sequence; /* seq. num. of clear event */
struct pps_ktime_compat assert_tu; /* time of assert event */
struct pps_ktime_compat clear_tu; /* time of clear event */
int current_mode; /* current mode bits */
};
struct pps_kparams {
int api_version; /* API version # */
int mode; /* mode bits */
struct pps_ktime assert_off_tu; /* offset compensation for assert */
struct pps_ktime clear_off_tu; /* offset compensation for clear */
};
/*
* 3.3 Mode bit definitions
*/
/* Device/implementation parameters */
#define PPS_CAPTUREASSERT 0x01 /* capture assert events */
#define PPS_CAPTURECLEAR 0x02 /* capture clear events */
#define PPS_CAPTUREBOTH 0x03 /* capture assert and clear events */
#define PPS_OFFSETASSERT 0x10 /* apply compensation for assert event */
#define PPS_OFFSETCLEAR 0x20 /* apply compensation for clear event */
#define PPS_CANWAIT 0x100 /* can we wait for an event? */
#define PPS_CANPOLL 0x200 /* bit reserved for future use */
/* Kernel actions */
#define PPS_ECHOASSERT 0x40 /* feed back assert event to output */
#define PPS_ECHOCLEAR 0x80 /* feed back clear event to output */
/* Timestamp formats */
#define PPS_TSFMT_TSPEC 0x1000 /* select timespec format */
#define PPS_TSFMT_NTPFP 0x2000 /* select NTP format */
/*
* 3.4.4 New functions: disciplining the kernel timebase
*/
/* Kernel consumers */
#define PPS_KC_HARDPPS 0 /* hardpps() (or equivalent) */
#define PPS_KC_HARDPPS_PLL 1 /* hardpps() constrained to
use a phase-locked loop */
#define PPS_KC_HARDPPS_FLL 2 /* hardpps() constrained to
use a frequency-locked loop */
/*
* Here begins the implementation-specific part!
*/
struct pps_fdata {
struct pps_kinfo info;
struct pps_ktime timeout;
};
struct pps_fdata_compat {
struct pps_kinfo_compat info;
struct pps_ktime_compat timeout;
};
struct pps_bind_args {
int tsformat; /* format of time stamps */
int edge; /* selected event type */
int consumer; /* selected kernel consumer */
};
#include <linux/ioctl.h>
#define PPS_GETPARAMS _IOR('p', 0xa1, struct pps_kparams *)
#define PPS_SETPARAMS _IOW('p', 0xa2, struct pps_kparams *)
#define PPS_GETCAP _IOR('p', 0xa3, int *)
#define PPS_FETCH _IOWR('p', 0xa4, struct pps_fdata *)
#define PPS_KC_BIND _IOW('p', 0xa5, struct pps_bind_args *)
#endif /* _PPS_H_ */