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/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 /**
 140  * ptp_clock_index() - obtain the device index of a PTP clock
 141  *
 142  * @ptp:    The clock obtained from ptp_clock_register().
 143  */
 144
 145 extern int ptp_clock_index(struct ptp_clock *ptp);
 146
 147 #endif