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 "friendly name" to identify the clock and to
  46  *             help distinguish PHY based devices from MAC based ones.
  47  *             The string is not meant to be a unique id.
  48  * @max_adj:   The maximum possible frequency adjustment, in parts per billon.
  49  * @n_alarm:   The number of programmable alarms.
  50  * @n_ext_ts:  The number of external time stamp channels.
  51  * @n_per_out: The number of programmable periodic signals.
  52  * @n_pins:    The number of programmable pins.
  53  * @pps:       Indicates whether the clock supports a PPS callback.
  54  * @pin_config: Array of length 'n_pins'. If the number of
  55  *              programmable pins is nonzero, then drivers must
  56  *              allocate and initialize this array.
  57  *
  58  * clock operations
  59  *
  60  * @adjfreq:  Adjusts the frequency of the hardware clock.
  61  *            parameter delta: Desired frequency offset from nominal frequency
  62  *            in parts per billion
  63  *
  64  * @adjtime:  Shifts the time of the hardware clock.
  65  *            parameter delta: Desired change in nanoseconds.
  66  *
  67  * @gettime64:  Reads the current time from the hardware clock.
  68  *              parameter ts: Holds the result.
  69  *
  70  * @settime64:  Set the current time on the hardware clock.
  71  *              parameter ts: Time value to set.
  72  *
  73  * @enable:   Request driver to enable or disable an ancillary feature.
  74  *            parameter request: Desired resource to enable or disable.
  75  *            parameter on: Caller passes one to enable or zero to disable.
  76  *
  77  * @verify:   Confirm that a pin can perform a given function. The PTP
  78  *            Hardware Clock subsystem maintains the 'pin_config'
  79  *            array on behalf of the drivers, but the PHC subsystem
  80  *            assumes that every pin can perform every function. This
  81  *            hook gives drivers a way of telling the core about
  82  *            limitations on specific pins. This function must return
  83  *            zero if the function can be assigned to this pin, and
  84  *            nonzero otherwise.
  85  *            parameter pin: index of the pin in question.
  86  *            parameter func: the desired function to use.
  87  *            parameter chan: the function channel index to use.
  88  *
  89  * Drivers should embed their ptp_clock_info within a private
  90  * structure, obtaining a reference to it using container_of().
  91  *
  92  * The callbacks must all return zero on success, non-zero otherwise.
  93  */
  94
  95 struct ptp_clock_info {
  96         struct module *owner;
  97         char name[16];
  98         s32 max_adj;
  99         int n_alarm;
 100         int n_ext_ts;
 101         int n_per_out;
 102         int n_pins;
 103         int pps;
 104         struct ptp_pin_desc *pin_config;
 105         int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
 106         int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
 107         int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts);
 108         int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts);
 109         int (*enable)(struct ptp_clock_info *ptp,
 110                       struct ptp_clock_request *request, int on);
 111         int (*verify)(struct ptp_clock_info *ptp, unsigned int pin,
 112                       enum ptp_pin_function func, unsigned int chan);
 113 };
 114
 115 struct ptp_clock;
 116
 117 /**
 118  * ptp_clock_register() - register a PTP hardware clock driver
 119  *
 120  * @info:   Structure describing the new clock.
 121  * @parent: Pointer to the parent device of the new clock.
 122  */
 123
 124 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 125                                             struct device *parent);
 126
 127 /**
 128  * ptp_clock_unregister() - unregister a PTP hardware clock driver
 129  *
 130  * @ptp:  The clock to remove from service.
 131  */
 132
 133 extern int ptp_clock_unregister(struct ptp_clock *ptp);
 134
 135
 136 enum ptp_clock_events {
 137         PTP_CLOCK_ALARM,
 138         PTP_CLOCK_EXTTS,
 139         PTP_CLOCK_PPS,
 140         PTP_CLOCK_PPSUSR,
 141 };
 142
 143 /**
 144  * struct ptp_clock_event - decribes a PTP hardware clock event
 145  *
 146  * @type:  One of the ptp_clock_events enumeration values.
 147  * @index: Identifies the source of the event.
 148  * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
 149  * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
 150  */
 151
 152 struct ptp_clock_event {
 153         int type;
 154         int index;
 155         union {
 156                 u64 timestamp;
 157                 struct pps_event_time pps_times;
 158         };
 159 };
 160
 161 /**
 162  * ptp_clock_event() - notify the PTP layer about an event
 163  *
 164  * @ptp:    The clock obtained from ptp_clock_register().
 165  * @event:  Message structure describing the event.
 166  */
 167
 168 extern void ptp_clock_event(struct ptp_clock *ptp,
 169                             struct ptp_clock_event *event);
 170
 171 /**
 172  * ptp_clock_index() - obtain the device index of a PTP clock
 173  *
 174  * @ptp:    The clock obtained from ptp_clock_register().
 175  */
 176
 177 extern int ptp_clock_index(struct ptp_clock *ptp);
 178
 179 /**
 180  * ptp_find_pin() - obtain the pin index of a given auxiliary function
 181  *
 182  * @ptp:    The clock obtained from ptp_clock_register().
 183  * @func:   One of the ptp_pin_function enumerated values.
 184  * @chan:   The particular functional channel to find.
 185  * Return:  Pin index in the range of zero to ptp_clock_caps.n_pins - 1,
 186  *          or -1 if the auxiliary function cannot be found.
 187  */
 188
 189 int ptp_find_pin(struct ptp_clock *ptp,
 190                  enum ptp_pin_function func, unsigned int chan);
 191
 192 #endif