/*
 * PTP 1588 clock support - user space interface
 *
 * Copyright (C) 2010 OMICRON electronics GmbH
 *
 *  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 _PTP_CLOCK_H_
#define _PTP_CLOCK_H_

#include <linux/ioctl.h>
#include <linux/types.h>

/* PTP_xxx bits, for the flags field within the request structures. */
#define PTP_ENABLE_FEATURE (1<<0)
#define PTP_RISING_EDGE    (1<<1)
#define PTP_FALLING_EDGE   (1<<2)

/*
 * struct ptp_clock_time - represents a time value
 *
 * The sign of the seconds field applies to the whole value. The
 * nanoseconds field is always unsigned. The reserved field is
 * included for sub-nanosecond resolution, should the demand for
 * this ever appear.
 *
 */
struct ptp_clock_time {
	__s64 sec;  /* seconds */
	__u32 nsec; /* nanoseconds */
	__u32 reserved;
};

struct ptp_clock_caps {
	int max_adj;   /* Maximum frequency adjustment in parts per billon. */
	int n_alarm;   /* Number of programmable alarms. */
	int n_ext_ts;  /* Number of external time stamp channels. */
	int n_per_out; /* Number of programmable periodic signals. */
	int pps;       /* Whether the clock supports a PPS callback. */
	int n_pins;    /* Number of input/output pins. */
	int rsv[14];   /* Reserved for future use. */
};

struct ptp_extts_request {
	unsigned int index;  /* Which channel to configure. */
	unsigned int flags;  /* Bit field for PTP_xxx flags. */
	unsigned int rsv[2]; /* Reserved for future use. */
};

struct ptp_perout_request {
	struct ptp_clock_time start;  /* Absolute start time. */
	struct ptp_clock_time period; /* Desired period, zero means disable. */
	unsigned int index;           /* Which channel to configure. */
	unsigned int flags;           /* Reserved for future use. */
	unsigned int rsv[4];          /* Reserved for future use. */
};

#define PTP_MAX_SAMPLES 25 /* Maximum allowed offset measurement samples. */

struct ptp_sys_offset {
	unsigned int n_samples; /* Desired number of measurements. */
	unsigned int rsv[3];    /* Reserved for future use. */
	/*
	 * Array of interleaved system/phc time stamps. The kernel
	 * will provide 2*n_samples + 1 time stamps, with the last
	 * one as a system time stamp.
	 */
	struct ptp_clock_time ts[2 * PTP_MAX_SAMPLES + 1];
};

enum ptp_pin_function {
	PTP_PF_NONE,
	PTP_PF_EXTTS,
	PTP_PF_PEROUT,
	PTP_PF_PHYSYNC,
};

struct ptp_pin_desc {
	/*
	 * Hardware specific human readable pin name. This field is
	 * set by the kernel during the PTP_PIN_GETFUNC ioctl and is
	 * ignored for the PTP_PIN_SETFUNC ioctl.
	 */
	char name[64];
	/*
	 * Pin index in the range of zero to ptp_clock_caps.n_pins - 1.
	 */
	unsigned int index;
	/*
	 * Which of the PTP_PF_xxx functions to use on this pin.
	 */
	unsigned int func;
	/*
	 * The specific channel to use for this function.
	 * This corresponds to the 'index' field of the
	 * PTP_EXTTS_REQUEST and PTP_PEROUT_REQUEST ioctls.
	 */
	unsigned int chan;
	/*
	 * Reserved for future use.
	 */
	unsigned int rsv[5];
};

#define PTP_CLK_MAGIC '='

#define PTP_CLOCK_GETCAPS  _IOR(PTP_CLK_MAGIC, 1, struct ptp_clock_caps)
#define PTP_EXTTS_REQUEST  _IOW(PTP_CLK_MAGIC, 2, struct ptp_extts_request)
#define PTP_PEROUT_REQUEST _IOW(PTP_CLK_MAGIC, 3, struct ptp_perout_request)
#define PTP_ENABLE_PPS     _IOW(PTP_CLK_MAGIC, 4, int)
#define PTP_SYS_OFFSET     _IOW(PTP_CLK_MAGIC, 5, struct ptp_sys_offset)
#define PTP_PIN_GETFUNC    _IOWR(PTP_CLK_MAGIC, 6, struct ptp_pin_desc)
#define PTP_PIN_SETFUNC    _IOW(PTP_CLK_MAGIC, 7, struct ptp_pin_desc)

struct ptp_extts_event {
	struct ptp_clock_time t; /* Time event occured. */
	unsigned int index;      /* Which channel produced the event. */
	unsigned int flags;      /* Reserved for future use. */
	unsigned int rsv[2];     /* Reserved for future use. */
};

#endif