/*
* PTP 1588 clock support
*
* 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_KERNEL_H_
#define _PTP_CLOCK_KERNEL_H_
#include <linux/device.h>
#include <linux/pps_kernel.h>
#include <linux/ptp_clock.h>
struct ptp_clock_request {
enum {
PTP_CLK_REQ_EXTTS,
PTP_CLK_REQ_PEROUT,
PTP_CLK_REQ_PPS,
} type;
union {
struct ptp_extts_request extts;
struct ptp_perout_request perout;
};
};
/**
* struct ptp_clock_info - decribes a PTP hardware clock
*
* @owner: The clock driver should set to THIS_MODULE.
* @name: A short "friendly name" to identify the clock and to
* help distinguish PHY based devices from MAC based ones.
* The string is not meant to be a unique id.
* @max_adj: The maximum possible frequency adjustment, in parts per billon.
* @n_alarm: The number of programmable alarms.
* @n_ext_ts: The number of external time stamp channels.
* @n_per_out: The number of programmable periodic signals.
* @n_pins: The number of programmable pins.
* @pps: Indicates whether the clock supports a PPS callback.
* @pin_config: Array of length 'n_pins'. If the number of
* programmable pins is nonzero, then drivers must
* allocate and initialize this array.
*
* clock operations
*
* @adjfreq: Adjusts the frequency of the hardware clock.
* parameter delta: Desired frequency offset from nominal frequency
* in parts per billion
*
* @adjtime: Shifts the time of the hardware clock.
* parameter delta: Desired change in nanoseconds.
*
* @gettime: Reads the current time from the hardware clock.
* parameter ts: Holds the result.
*
* @settime: Set the current time on the hardware clock.
* parameter ts: Time value to set.
*
* @enable: Request driver to enable or disable an ancillary feature.
* parameter request: Desired resource to enable or disable.
* parameter on: Caller passes one to enable or zero to disable.
*
* @verify: Confirm that a pin can perform a given function. The PTP
* Hardware Clock subsystem maintains the 'pin_config'
* array on behalf of the drivers, but the PHC subsystem
* assumes that every pin can perform every function. This
* hook gives drivers a way of telling the core about
* limitations on specific pins. This function must return
* zero if the function can be assigned to this pin, and
* nonzero otherwise.
* parameter pin: index of the pin in question.
* parameter func: the desired function to use.
* parameter chan: the function channel index to use.
*
* Drivers should embed their ptp_clock_info within a private
* structure, obtaining a reference to it using container_of().
*
* The callbacks must all return zero on success, non-zero otherwise.
*/
struct ptp_clock_info {
struct module *owner;
char name[16];
s32 max_adj;
int n_alarm;
int n_ext_ts;
int n_per_out;
int n_pins;
int pps;
struct ptp_pin_desc *pin_config;
int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts);
int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts);
int (*enable)(struct ptp_clock_info *ptp,
struct ptp_clock_request *request, int on);
int (*verify)(struct ptp_clock_info *ptp, unsigned int pin,
enum ptp_pin_function func, unsigned int chan);
};
struct ptp_clock;
/**
* ptp_clock_register() - register a PTP hardware clock driver
*
* @info: Structure describing the new clock.
* @parent: Pointer to the parent device of the new clock.
*/
extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
struct device *parent);
/**
* ptp_clock_unregister() - unregister a PTP hardware clock driver
*
* @ptp: The clock to remove from service.
*/
extern int ptp_clock_unregister(struct ptp_clock *ptp);
enum ptp_clock_events {
PTP_CLOCK_ALARM,
PTP_CLOCK_EXTTS,
PTP_CLOCK_PPS,
PTP_CLOCK_PPSUSR,
};
/**
* struct ptp_clock_event - decribes a PTP hardware clock event
*
* @type: One of the ptp_clock_events enumeration values.
* @index: Identifies the source of the event.
* @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
* @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
*/
struct ptp_clock_event {
int type;
int index;
union {
u64 timestamp;
struct pps_event_time pps_times;
};
};
/**
* ptp_clock_event() - notify the PTP layer about an event
*
* @ptp: The clock obtained from ptp_clock_register().
* @event: Message structure describing the event.
*/
extern void ptp_clock_event(struct ptp_clock *ptp,
struct ptp_clock_event *event);
/**
* ptp_clock_index() - obtain the device index of a PTP clock
*
* @ptp: The clock obtained from ptp_clock_register().
*/
extern int ptp_clock_index(struct ptp_clock *ptp);
/**
* ptp_find_pin() - obtain the pin index of a given auxiliary function
*
* @ptp: The clock obtained from ptp_clock_register().
* @func: One of the ptp_pin_function enumerated values.
* @chan: The particular functional channel to find.
* Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1,
* or -1 if the auxiliary function cannot be found.
*/
int ptp_find_pin(struct ptp_clock *ptp,
enum ptp_pin_function func, unsigned int chan);
#endif