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/device.h>
  25 #include <linux/pps_kernel.h>
  26 #include <linux/ptp_clock.h>
  27
  28
  29 struct ptp_clock_request {
  30         enum {
  31                 PTP_CLK_REQ_EXTTS,
  32                 PTP_CLK_REQ_PEROUT,
  33                 PTP_CLK_REQ_PPS,
  34         } type;
  35         union {
  36                 struct ptp_extts_request extts;
  37                 struct ptp_perout_request perout;
  38         };
  39 };
  40
  41 /**
  42  * struct ptp_clock_info - decribes a PTP hardware clock
  43  *
  44  * @owner:     The clock driver should set to THIS_MODULE.
  45  * @name:      A short name to identify the clock.
  46  * @max_adj:   The maximum possible frequency adjustment, in parts per billon.
  47  * @n_alarm:   The number of programmable alarms.
  48  * @n_ext_ts:  The number of external time stamp channels.
  49  * @n_per_out: The number of programmable periodic signals.
  50  * @pps:       Indicates whether the clock supports a PPS callback.
  51  *
  52  * clock operations
  53  *
  54  * @adjfreq:  Adjusts the frequency of the hardware clock.
  55  *            parameter delta: Desired period change in parts per billion.
  56  *
  57  * @adjtime:  Shifts the time of the hardware clock.
  58  *            parameter delta: Desired change in nanoseconds.
  59  *
  60  * @gettime:  Reads the current time from the hardware clock.
  61  *            parameter ts: Holds the result.
  62  *
  63  * @settime:  Set the current time on the hardware clock.
  64  *            parameter ts: Time value to set.
  65  *
  66  * @enable:   Request driver to enable or disable an ancillary feature.
  67  *            parameter request: Desired resource to enable or disable.
  68  *            parameter on: Caller passes one to enable or zero to disable.
  69  *
  70  * Drivers should embed their ptp_clock_info within a private
  71  * structure, obtaining a reference to it using container_of().
  72  *
  73  * The callbacks must all return zero on success, non-zero otherwise.
  74  */
  75
  76 struct ptp_clock_info {
  77         struct module *owner;
  78         char name[16];
  79         s32 max_adj;
  80         int n_alarm;
  81         int n_ext_ts;
  82         int n_per_out;
  83         int pps;
  84         int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
  85         int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
  86         int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts);
  87         int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts);
  88         int (*enable)(struct ptp_clock_info *ptp,
  89                       struct ptp_clock_request *request, int on);
  90 };
  91
  92 struct ptp_clock;
  93
  94 /**
  95  * ptp_clock_register() - register a PTP hardware clock driver
  96  *
  97  * @info:   Structure describing the new clock.
  98  * @parent: Pointer to the parent device of the new clock.
  99  */
 100
 101 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 102                                             struct device *parent);
 103
 104 /**
 105  * ptp_clock_unregister() - unregister a PTP hardware clock driver
 106  *
 107  * @ptp:  The clock to remove from service.
 108  */
 109
 110 extern int ptp_clock_unregister(struct ptp_clock *ptp);
 111
 112
 113 enum ptp_clock_events {
 114         PTP_CLOCK_ALARM,
 115         PTP_CLOCK_EXTTS,
 116         PTP_CLOCK_PPS,
 117         PTP_CLOCK_PPSUSR,
 118 };
 119
 120 /**
 121  * struct ptp_clock_event - decribes a PTP hardware clock event
 122  *
 123  * @type:  One of the ptp_clock_events enumeration values.
 124  * @index: Identifies the source of the event.
 125  * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
 126  * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
 127  */
 128
 129 struct ptp_clock_event {
 130         int type;
 131         int index;
 132         union {
 133                 u64 timestamp;
 134                 struct pps_event_time pps_times;
 135         };
 136 };
 137
 138 /**
 139  * ptp_clock_event() - notify the PTP layer about an event
 140  *
 141  * @ptp:    The clock obtained from ptp_clock_register().
 142  * @event:  Message structure describing the event.
 143  */
 144
 145 extern void ptp_clock_event(struct ptp_clock *ptp,
 146                             struct ptp_clock_event *event);
 147
 148 /**
 149  * ptp_clock_index() - obtain the device index of a PTP clock
 150  *
 151  * @ptp:    The clock obtained from ptp_clock_register().
 152  */
 153
 154 extern int ptp_clock_index(struct ptp_clock *ptp);
 155
 156 #endif