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 struct system_device_crosststamp; 42 /** 43 * struct ptp_clock_info - decribes a PTP hardware clock 44 * 45 * @owner: The clock driver should set to THIS_MODULE. 46 * @name: A short "friendly name" to identify the clock and to 47 * help distinguish PHY based devices from MAC based ones. 48 * The string is not meant to be a unique id. 49 * @max_adj: The maximum possible frequency adjustment, in parts per billon. 50 * @n_alarm: The number of programmable alarms. 51 * @n_ext_ts: The number of external time stamp channels. 52 * @n_per_out: The number of programmable periodic signals. 53 * @n_pins: The number of programmable pins. 54 * @pps: Indicates whether the clock supports a PPS callback. 55 * @pin_config: Array of length 'n_pins'. If the number of 56 * programmable pins is nonzero, then drivers must 57 * allocate and initialize this array. 58 * 59 * clock operations 60 * 61 * @adjfine: Adjusts the frequency of the hardware clock. 62 * parameter scaled_ppm: Desired frequency offset from 63 * nominal frequency in parts per million, but with a 64 * 16 bit binary fractional field. 65 * 66 * @adjfreq: Adjusts the frequency of the hardware clock. 67 * This method is deprecated. New drivers should implement 68 * the @adjfine method instead. 69 * parameter delta: Desired frequency offset from nominal frequency 70 * in parts per billion 71 * 72 * @adjtime: Shifts the time of the hardware clock. 73 * parameter delta: Desired change in nanoseconds. 74 * 75 * @gettime64: Reads the current time from the hardware clock. 76 * parameter ts: Holds the result. 77 * 78 * @getcrosststamp: Reads the current time from the hardware clock and 79 * system clock simultaneously. 80 * parameter cts: Contains timestamp (device,system) pair, 81 * where system time is realtime and monotonic. 82 * 83 * @settime64: Set the current time on the hardware clock. 84 * parameter ts: Time value to set. 85 * 86 * @enable: Request driver to enable or disable an ancillary feature. 87 * parameter request: Desired resource to enable or disable. 88 * parameter on: Caller passes one to enable or zero to disable. 89 * 90 * @verify: Confirm that a pin can perform a given function. The PTP 91 * Hardware Clock subsystem maintains the 'pin_config' 92 * array on behalf of the drivers, but the PHC subsystem 93 * assumes that every pin can perform every function. This 94 * hook gives drivers a way of telling the core about 95 * limitations on specific pins. This function must return 96 * zero if the function can be assigned to this pin, and 97 * nonzero otherwise. 98 * parameter pin: index of the pin in question. 99 * parameter func: the desired function to use. 100 * parameter chan: the function channel index to use. 101 * 102 * Drivers should embed their ptp_clock_info within a private 103 * structure, obtaining a reference to it using container_of(). 104 * 105 * The callbacks must all return zero on success, non-zero otherwise. 106 */ 107 108 struct ptp_clock_info { 109 struct module *owner; 110 char name[16]; 111 s32 max_adj; 112 int n_alarm; 113 int n_ext_ts; 114 int n_per_out; 115 int n_pins; 116 int pps; 117 struct ptp_pin_desc *pin_config; 118 int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm); 119 int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta); 120 int (*adjtime)(struct ptp_clock_info *ptp, s64 delta); 121 int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts); 122 int (*getcrosststamp)(struct ptp_clock_info *ptp, 123 struct system_device_crosststamp *cts); 124 int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts); 125 int (*enable)(struct ptp_clock_info *ptp, 126 struct ptp_clock_request *request, int on); 127 int (*verify)(struct ptp_clock_info *ptp, unsigned int pin, 128 enum ptp_pin_function func, unsigned int chan); 129 }; 130 131 struct ptp_clock; 132 133 /** 134 * ptp_clock_register() - register a PTP hardware clock driver 135 * 136 * @info: Structure describing the new clock. 137 * @parent: Pointer to the parent device of the new clock. 138 * 139 * Returns a valid pointer on success or PTR_ERR on failure. If PHC 140 * support is missing at the configuration level, this function 141 * returns NULL, and drivers are expected to gracefully handle that 142 * case separately. 143 */ 144 145 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 146 struct device *parent); 147 148 /** 149 * ptp_clock_unregister() - unregister a PTP hardware clock driver 150 * 151 * @ptp: The clock to remove from service. 152 */ 153 154 extern int ptp_clock_unregister(struct ptp_clock *ptp); 155 156 157 enum ptp_clock_events { 158 PTP_CLOCK_ALARM, 159 PTP_CLOCK_EXTTS, 160 PTP_CLOCK_PPS, 161 PTP_CLOCK_PPSUSR, 162 }; 163 164 /** 165 * struct ptp_clock_event - decribes a PTP hardware clock event 166 * 167 * @type: One of the ptp_clock_events enumeration values. 168 * @index: Identifies the source of the event. 169 * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only). 170 * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only). 171 */ 172 173 struct ptp_clock_event { 174 int type; 175 int index; 176 union { 177 u64 timestamp; 178 struct pps_event_time pps_times; 179 }; 180 }; 181 182 /** 183 * ptp_clock_event() - notify the PTP layer about an event 184 * 185 * @ptp: The clock obtained from ptp_clock_register(). 186 * @event: Message structure describing the event. 187 */ 188 189 extern void ptp_clock_event(struct ptp_clock *ptp, 190 struct ptp_clock_event *event); 191 192 /** 193 * ptp_clock_index() - obtain the device index of a PTP clock 194 * 195 * @ptp: The clock obtained from ptp_clock_register(). 196 */ 197 198 extern int ptp_clock_index(struct ptp_clock *ptp); 199 200 /** 201 * ptp_find_pin() - obtain the pin index of a given auxiliary function 202 * 203 * @ptp: The clock obtained from ptp_clock_register(). 204 * @func: One of the ptp_pin_function enumerated values. 205 * @chan: The particular functional channel to find. 206 * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1, 207 * or -1 if the auxiliary function cannot be found. 208 */ 209 210 int ptp_find_pin(struct ptp_clock *ptp, 211 enum ptp_pin_function func, unsigned int chan); 212 213 #endif 214