include/linux/ptp_clock_kernel.h

   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/pps_kernel.h>
  25 #include <linux/ptp_clock.h>
  26
  27
  28 struct ptp_clock_request {
  29         enum {
  30                 PTP_CLK_REQ_EXTTS,
  31                 PTP_CLK_REQ_PEROUT,
  32                 PTP_CLK_REQ_PPS,
  33         } type;
  34         union {
  35                 struct ptp_extts_request extts;
  36                 struct ptp_perout_request perout;
  37         };
  38 };
  39
  40 /**
  41  * struct ptp_clock_info - decribes a PTP hardware clock
  42  *
  43  * @owner:     The clock driver should set to THIS_MODULE.
  44  * @name:      A short name to identify the clock.
  45  * @max_adj:   The maximum possible frequency adjustment, in parts per billon.
  46  * @n_alarm:   The number of programmable alarms.
  47  * @n_ext_ts:  The number of external time stamp channels.
  48  * @n_per_out: The number of programmable periodic signals.
  49  * @pps:       Indicates whether the clock supports a PPS callback.
  50  *
  51  * clock operations
  52  *
  53  * @adjfreq:  Adjusts the frequency of the hardware clock.
  54  *            parameter delta: Desired period change in parts per billion.
  55  *
  56  * @adjtime:  Shifts the time of the hardware clock.
  57  *            parameter delta: Desired change in nanoseconds.
  58  *
  59  * @gettime:  Reads the current time from the hardware clock.
  60  *            parameter ts: Holds the result.
  61  *
  62  * @settime:  Set the current time on the hardware clock.
  63  *            parameter ts: Time value to set.
  64  *
  65  * @enable:   Request driver to enable or disable an ancillary feature.
  66  *            parameter request: Desired resource to enable or disable.
  67  *            parameter on: Caller passes one to enable or zero to disable.
  68  *
  69  * Drivers should embed their ptp_clock_info within a private
  70  * structure, obtaining a reference to it using container_of().
  71  *
  72  * The callbacks must all return zero on success, non-zero otherwise.
  73  */
  74
  75 struct ptp_clock_info {
  76         struct module *owner;
  77         char name[16];
  78         s32 max_adj;
  79         int n_alarm;
  80         int n_ext_ts;
  81         int n_per_out;
  82         int pps;
  83         int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
  84         int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
  85         int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts);
  86         int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts);
  87         int (*enable)(struct ptp_clock_info *ptp,
  88                       struct ptp_clock_request *request, int on);
  89 };
  90
  91 struct ptp_clock;
  92
  93 /**
  94  * ptp_clock_register() - register a PTP hardware clock driver
  95  *
  96  * @info:  Structure describing the new clock.
  97  */
  98
  99 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info);
 100
 101 /**
 102  * ptp_clock_unregister() - unregister a PTP hardware clock driver
 103  *
 104  * @ptp:  The clock to remove from service.
 105  */
 106
 107 extern int ptp_clock_unregister(struct ptp_clock *ptp);
 108
 109
 110 enum ptp_clock_events {
 111         PTP_CLOCK_ALARM,
 112         PTP_CLOCK_EXTTS,
 113         PTP_CLOCK_PPS,
 114         PTP_CLOCK_PPSUSR,
 115 };
 116
 117 /**
 118  * struct ptp_clock_event - decribes a PTP hardware clock event
 119  *
 120  * @type:  One of the ptp_clock_events enumeration values.
 121  * @index: Identifies the source of the event.
 122  * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
 123  * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
 124  */
 125
 126 struct ptp_clock_event {
 127         int type;
 128         int index;
 129         union {
 130                 u64 timestamp;
 131                 struct pps_event_time pps_times;
 132         };
 133 };
 134
 135 /**
 136  * ptp_clock_event() - notify the PTP layer about an event
 137  *
 138  * @ptp:    The clock obtained from ptp_clock_register().
 139  * @event:  Message structure describing the event.
 140  */
 141
 142 extern void ptp_clock_event(struct ptp_clock *ptp,
 143                             struct ptp_clock_event *event);
 144
 145 /**
 146  * ptp_clock_index() - obtain the device index of a PTP clock
 147  *
 148  * @ptp:    The clock obtained from ptp_clock_register().
 149  */
 150
 151 extern int ptp_clock_index(struct ptp_clock *ptp);
 152
 153 #endif