1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * PTP 1588 clock support 4 * 5 * Copyright (C) 2010 OMICRON electronics GmbH 6 */ 7 8 #ifndef _PTP_CLOCK_KERNEL_H_ 9 #define _PTP_CLOCK_KERNEL_H_ 10 11 #include <linux/device.h> 12 #include <linux/pps_kernel.h> 13 #include <linux/ptp_clock.h> 14 15 /** 16 * struct ptp_clock_request - request PTP clock event 17 * 18 * @type: The type of the request. 19 * EXTTS: Configure external trigger timestamping 20 * PEROUT: Configure periodic output signal (e.g. PPS) 21 * PPS: trigger internal PPS event for input 22 * into kernel PPS subsystem 23 * @extts: describes configuration for external trigger timestamping. 24 * This is only valid when event == PTP_CLK_REQ_EXTTS. 25 * @perout: describes configuration for periodic output. 26 * This is only valid when event == PTP_CLK_REQ_PEROUT. 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 /** 44 * struct ptp_system_timestamp - system time corresponding to a PHC timestamp 45 */ 46 struct ptp_system_timestamp { 47 struct timespec64 pre_ts; 48 struct timespec64 post_ts; 49 }; 50 51 /** 52 * struct ptp_clock_info - describes a PTP hardware clock 53 * 54 * @owner: The clock driver should set to THIS_MODULE. 55 * @name: A short "friendly name" to identify the clock and to 56 * help distinguish PHY based devices from MAC based ones. 57 * The string is not meant to be a unique id. 58 * @max_adj: The maximum possible frequency adjustment, in parts per billon. 59 * @n_alarm: The number of programmable alarms. 60 * @n_ext_ts: The number of external time stamp channels. 61 * @n_per_out: The number of programmable periodic signals. 62 * @n_pins: The number of programmable pins. 63 * @pps: Indicates whether the clock supports a PPS callback. 64 * @pin_config: Array of length 'n_pins'. If the number of 65 * programmable pins is nonzero, then drivers must 66 * allocate and initialize this array. 67 * 68 * clock operations 69 * 70 * @adjfine: Adjusts the frequency of the hardware clock. 71 * parameter scaled_ppm: Desired frequency offset from 72 * nominal frequency in parts per million, but with a 73 * 16 bit binary fractional field. 74 * 75 * @adjfreq: Adjusts the frequency of the hardware clock. 76 * This method is deprecated. New drivers should implement 77 * the @adjfine method instead. 78 * parameter delta: Desired frequency offset from nominal frequency 79 * in parts per billion 80 * 81 * @adjphase: Adjusts the phase offset of the hardware clock. 82 * parameter delta: Desired change in nanoseconds. 83 * 84 * @adjtime: Shifts the time of the hardware clock. 85 * parameter delta: Desired change in nanoseconds. 86 * 87 * @gettime64: Reads the current time from the hardware clock. 88 * This method is deprecated. New drivers should implement 89 * the @gettimex64 method instead. 90 * parameter ts: Holds the result. 91 * 92 * @gettimex64: Reads the current time from the hardware clock and optionally 93 * also the system clock. 94 * parameter ts: Holds the PHC timestamp. 95 * parameter sts: If not NULL, it holds a pair of timestamps from 96 * the system clock. The first reading is made right before 97 * reading the lowest bits of the PHC timestamp and the second 98 * reading immediately follows that. 99 * 100 * @getcrosststamp: Reads the current time from the hardware clock and 101 * system clock simultaneously. 102 * parameter cts: Contains timestamp (device,system) pair, 103 * where system time is realtime and monotonic. 104 * 105 * @settime64: Set the current time on the hardware clock. 106 * parameter ts: Time value to set. 107 * 108 * @enable: Request driver to enable or disable an ancillary feature. 109 * parameter request: Desired resource to enable or disable. 110 * parameter on: Caller passes one to enable or zero to disable. 111 * 112 * @verify: Confirm that a pin can perform a given function. The PTP 113 * Hardware Clock subsystem maintains the 'pin_config' 114 * array on behalf of the drivers, but the PHC subsystem 115 * assumes that every pin can perform every function. This 116 * hook gives drivers a way of telling the core about 117 * limitations on specific pins. This function must return 118 * zero if the function can be assigned to this pin, and 119 * nonzero otherwise. 120 * parameter pin: index of the pin in question. 121 * parameter func: the desired function to use. 122 * parameter chan: the function channel index to use. 123 * 124 * @do_aux_work: Request driver to perform auxiliary (periodic) operations 125 * Driver should return delay of the next auxiliary work 126 * scheduling time (>=0) or negative value in case further 127 * scheduling is not required. 128 * 129 * Drivers should embed their ptp_clock_info within a private 130 * structure, obtaining a reference to it using container_of(). 131 * 132 * The callbacks must all return zero on success, non-zero otherwise. 133 */ 134 135 struct ptp_clock_info { 136 struct module *owner; 137 char name[16]; 138 s32 max_adj; 139 int n_alarm; 140 int n_ext_ts; 141 int n_per_out; 142 int n_pins; 143 int pps; 144 struct ptp_pin_desc *pin_config; 145 int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm); 146 int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta); 147 int (*adjphase)(struct ptp_clock_info *ptp, s32 phase); 148 int (*adjtime)(struct ptp_clock_info *ptp, s64 delta); 149 int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts); 150 int (*gettimex64)(struct ptp_clock_info *ptp, struct timespec64 *ts, 151 struct ptp_system_timestamp *sts); 152 int (*getcrosststamp)(struct ptp_clock_info *ptp, 153 struct system_device_crosststamp *cts); 154 int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts); 155 int (*enable)(struct ptp_clock_info *ptp, 156 struct ptp_clock_request *request, int on); 157 int (*verify)(struct ptp_clock_info *ptp, unsigned int pin, 158 enum ptp_pin_function func, unsigned int chan); 159 long (*do_aux_work)(struct ptp_clock_info *ptp); 160 }; 161 162 struct ptp_clock; 163 164 enum ptp_clock_events { 165 PTP_CLOCK_ALARM, 166 PTP_CLOCK_EXTTS, 167 PTP_CLOCK_PPS, 168 PTP_CLOCK_PPSUSR, 169 }; 170 171 /** 172 * struct ptp_clock_event - decribes a PTP hardware clock event 173 * 174 * @type: One of the ptp_clock_events enumeration values. 175 * @index: Identifies the source of the event. 176 * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only). 177 * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only). 178 */ 179 180 struct ptp_clock_event { 181 int type; 182 int index; 183 union { 184 u64 timestamp; 185 struct pps_event_time pps_times; 186 }; 187 }; 188 189 #if IS_REACHABLE(CONFIG_PTP_1588_CLOCK) 190 191 /** 192 * ptp_clock_register() - register a PTP hardware clock driver 193 * 194 * @info: Structure describing the new clock. 195 * @parent: Pointer to the parent device of the new clock. 196 * 197 * Returns a valid pointer on success or PTR_ERR on failure. If PHC 198 * support is missing at the configuration level, this function 199 * returns NULL, and drivers are expected to gracefully handle that 200 * case separately. 201 */ 202 203 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 204 struct device *parent); 205 206 /** 207 * ptp_clock_unregister() - unregister a PTP hardware clock driver 208 * 209 * @ptp: The clock to remove from service. 210 */ 211 212 extern int ptp_clock_unregister(struct ptp_clock *ptp); 213 214 /** 215 * ptp_clock_event() - notify the PTP layer about an event 216 * 217 * @ptp: The clock obtained from ptp_clock_register(). 218 * @event: Message structure describing the event. 219 */ 220 221 extern void ptp_clock_event(struct ptp_clock *ptp, 222 struct ptp_clock_event *event); 223 224 /** 225 * ptp_clock_index() - obtain the device index of a PTP clock 226 * 227 * @ptp: The clock obtained from ptp_clock_register(). 228 */ 229 230 extern int ptp_clock_index(struct ptp_clock *ptp); 231 232 /** 233 * scaled_ppm_to_ppb() - convert scaled ppm to ppb 234 * 235 * @ppm: Parts per million, but with a 16 bit binary fractional field 236 */ 237 238 extern s32 scaled_ppm_to_ppb(long ppm); 239 240 /** 241 * ptp_find_pin() - obtain the pin index of a given auxiliary function 242 * 243 * The caller must hold ptp_clock::pincfg_mux. Drivers do not have 244 * access to that mutex as ptp_clock is an opaque type. However, the 245 * core code acquires the mutex before invoking the driver's 246 * ptp_clock_info::enable() callback, and so drivers may call this 247 * function from that context. 248 * 249 * @ptp: The clock obtained from ptp_clock_register(). 250 * @func: One of the ptp_pin_function enumerated values. 251 * @chan: The particular functional channel to find. 252 * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1, 253 * or -1 if the auxiliary function cannot be found. 254 */ 255 256 int ptp_find_pin(struct ptp_clock *ptp, 257 enum ptp_pin_function func, unsigned int chan); 258 259 /** 260 * ptp_find_pin_unlocked() - wrapper for ptp_find_pin() 261 * 262 * This function acquires the ptp_clock::pincfg_mux mutex before 263 * invoking ptp_find_pin(). Instead of using this function, drivers 264 * should most likely call ptp_find_pin() directly from their 265 * ptp_clock_info::enable() method. 266 * 267 */ 268 269 int ptp_find_pin_unlocked(struct ptp_clock *ptp, 270 enum ptp_pin_function func, unsigned int chan); 271 272 /** 273 * ptp_schedule_worker() - schedule ptp auxiliary work 274 * 275 * @ptp: The clock obtained from ptp_clock_register(). 276 * @delay: number of jiffies to wait before queuing 277 * See kthread_queue_delayed_work() for more info. 278 */ 279 280 int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay); 281 282 /** 283 * ptp_cancel_worker_sync() - cancel ptp auxiliary clock 284 * 285 * @ptp: The clock obtained from ptp_clock_register(). 286 */ 287 void ptp_cancel_worker_sync(struct ptp_clock *ptp); 288 289 #else 290 static inline struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 291 struct device *parent) 292 { return NULL; } 293 static inline int ptp_clock_unregister(struct ptp_clock *ptp) 294 { return 0; } 295 static inline void ptp_clock_event(struct ptp_clock *ptp, 296 struct ptp_clock_event *event) 297 { } 298 static inline int ptp_clock_index(struct ptp_clock *ptp) 299 { return -1; } 300 static inline int ptp_find_pin(struct ptp_clock *ptp, 301 enum ptp_pin_function func, unsigned int chan) 302 { return -1; } 303 static inline int ptp_schedule_worker(struct ptp_clock *ptp, 304 unsigned long delay) 305 { return -EOPNOTSUPP; } 306 static inline void ptp_cancel_worker_sync(struct ptp_clock *ptp) 307 { } 308 309 #endif 310 311 static inline void ptp_read_system_prets(struct ptp_system_timestamp *sts) 312 { 313 if (sts) 314 ktime_get_real_ts64(&sts->pre_ts); 315 } 316 317 static inline void ptp_read_system_postts(struct ptp_system_timestamp *sts) 318 { 319 if (sts) 320 ktime_get_real_ts64(&sts->post_ts); 321 } 322 323 #endif 324