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 { 17 enum { 18 PTP_CLK_REQ_EXTTS, 19 PTP_CLK_REQ_PEROUT, 20 PTP_CLK_REQ_PPS, 21 } type; 22 union { 23 struct ptp_extts_request extts; 24 struct ptp_perout_request perout; 25 }; 26 }; 27 28 struct system_device_crosststamp; 29 30 /** 31 * struct ptp_system_timestamp - system time corresponding to a PHC timestamp 32 */ 33 struct ptp_system_timestamp { 34 struct timespec64 pre_ts; 35 struct timespec64 post_ts; 36 }; 37 38 /** 39 * struct ptp_clock_info - describes a PTP hardware clock 40 * 41 * @owner: The clock driver should set to THIS_MODULE. 42 * @name: A short "friendly name" to identify the clock and to 43 * help distinguish PHY based devices from MAC based ones. 44 * The string is not meant to be a unique id. 45 * @max_adj: The maximum possible frequency adjustment, in parts per billon. 46 * @n_alarm: The number of programmable alarms. 47 * @n_ext_ts: The number of external time stamp channels. 48 * @n_per_out: The number of programmable periodic signals. 49 * @n_pins: The number of programmable pins. 50 * @pps: Indicates whether the clock supports a PPS callback. 51 * @pin_config: Array of length 'n_pins'. If the number of 52 * programmable pins is nonzero, then drivers must 53 * allocate and initialize this array. 54 * 55 * clock operations 56 * 57 * @adjfine: Adjusts the frequency of the hardware clock. 58 * parameter scaled_ppm: Desired frequency offset from 59 * nominal frequency in parts per million, but with a 60 * 16 bit binary fractional field. 61 * 62 * @adjfreq: Adjusts the frequency of the hardware clock. 63 * This method is deprecated. New drivers should implement 64 * the @adjfine method instead. 65 * parameter delta: Desired frequency offset from nominal frequency 66 * in parts per billion 67 * 68 * @adjphase: Adjusts the phase offset of the hardware clock. 69 * parameter delta: Desired change in nanoseconds. 70 * 71 * @adjtime: Shifts the time of the hardware clock. 72 * parameter delta: Desired change in nanoseconds. 73 * 74 * @gettime64: Reads the current time from the hardware clock. 75 * This method is deprecated. New drivers should implement 76 * the @gettimex64 method instead. 77 * parameter ts: Holds the result. 78 * 79 * @gettimex64: Reads the current time from the hardware clock and optionally 80 * also the system clock. 81 * parameter ts: Holds the PHC timestamp. 82 * parameter sts: If not NULL, it holds a pair of timestamps from 83 * the system clock. The first reading is made right before 84 * reading the lowest bits of the PHC timestamp and the second 85 * reading immediately follows that. 86 * 87 * @getcrosststamp: Reads the current time from the hardware clock and 88 * system clock simultaneously. 89 * parameter cts: Contains timestamp (device,system) pair, 90 * where system time is realtime and monotonic. 91 * 92 * @settime64: Set the current time on the hardware clock. 93 * parameter ts: Time value to set. 94 * 95 * @enable: Request driver to enable or disable an ancillary feature. 96 * parameter request: Desired resource to enable or disable. 97 * parameter on: Caller passes one to enable or zero to disable. 98 * 99 * @verify: Confirm that a pin can perform a given function. The PTP 100 * Hardware Clock subsystem maintains the 'pin_config' 101 * array on behalf of the drivers, but the PHC subsystem 102 * assumes that every pin can perform every function. This 103 * hook gives drivers a way of telling the core about 104 * limitations on specific pins. This function must return 105 * zero if the function can be assigned to this pin, and 106 * nonzero otherwise. 107 * parameter pin: index of the pin in question. 108 * parameter func: the desired function to use. 109 * parameter chan: the function channel index to use. 110 * 111 * @do_aux_work: Request driver to perform auxiliary (periodic) operations 112 * Driver should return delay of the next auxiliary work 113 * scheduling time (>=0) or negative value in case further 114 * scheduling is not required. 115 * 116 * Drivers should embed their ptp_clock_info within a private 117 * structure, obtaining a reference to it using container_of(). 118 * 119 * The callbacks must all return zero on success, non-zero otherwise. 120 */ 121 122 struct ptp_clock_info { 123 struct module *owner; 124 char name[16]; 125 s32 max_adj; 126 int n_alarm; 127 int n_ext_ts; 128 int n_per_out; 129 int n_pins; 130 int pps; 131 struct ptp_pin_desc *pin_config; 132 int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm); 133 int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta); 134 int (*adjphase)(struct ptp_clock_info *ptp, s32 phase); 135 int (*adjtime)(struct ptp_clock_info *ptp, s64 delta); 136 int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts); 137 int (*gettimex64)(struct ptp_clock_info *ptp, struct timespec64 *ts, 138 struct ptp_system_timestamp *sts); 139 int (*getcrosststamp)(struct ptp_clock_info *ptp, 140 struct system_device_crosststamp *cts); 141 int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts); 142 int (*enable)(struct ptp_clock_info *ptp, 143 struct ptp_clock_request *request, int on); 144 int (*verify)(struct ptp_clock_info *ptp, unsigned int pin, 145 enum ptp_pin_function func, unsigned int chan); 146 long (*do_aux_work)(struct ptp_clock_info *ptp); 147 }; 148 149 struct ptp_clock; 150 151 enum ptp_clock_events { 152 PTP_CLOCK_ALARM, 153 PTP_CLOCK_EXTTS, 154 PTP_CLOCK_PPS, 155 PTP_CLOCK_PPSUSR, 156 }; 157 158 /** 159 * struct ptp_clock_event - decribes a PTP hardware clock event 160 * 161 * @type: One of the ptp_clock_events enumeration values. 162 * @index: Identifies the source of the event. 163 * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only). 164 * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only). 165 */ 166 167 struct ptp_clock_event { 168 int type; 169 int index; 170 union { 171 u64 timestamp; 172 struct pps_event_time pps_times; 173 }; 174 }; 175 176 #if IS_REACHABLE(CONFIG_PTP_1588_CLOCK) 177 178 /** 179 * ptp_clock_register() - register a PTP hardware clock driver 180 * 181 * @info: Structure describing the new clock. 182 * @parent: Pointer to the parent device of the new clock. 183 * 184 * Returns a valid pointer on success or PTR_ERR on failure. If PHC 185 * support is missing at the configuration level, this function 186 * returns NULL, and drivers are expected to gracefully handle that 187 * case separately. 188 */ 189 190 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 191 struct device *parent); 192 193 /** 194 * ptp_clock_unregister() - unregister a PTP hardware clock driver 195 * 196 * @ptp: The clock to remove from service. 197 */ 198 199 extern int ptp_clock_unregister(struct ptp_clock *ptp); 200 201 /** 202 * ptp_clock_event() - notify the PTP layer about an event 203 * 204 * @ptp: The clock obtained from ptp_clock_register(). 205 * @event: Message structure describing the event. 206 */ 207 208 extern void ptp_clock_event(struct ptp_clock *ptp, 209 struct ptp_clock_event *event); 210 211 /** 212 * ptp_clock_index() - obtain the device index of a PTP clock 213 * 214 * @ptp: The clock obtained from ptp_clock_register(). 215 */ 216 217 extern int ptp_clock_index(struct ptp_clock *ptp); 218 219 /** 220 * scaled_ppm_to_ppb() - convert scaled ppm to ppb 221 * 222 * @ppm: Parts per million, but with a 16 bit binary fractional field 223 */ 224 225 extern s32 scaled_ppm_to_ppb(long ppm); 226 227 /** 228 * ptp_find_pin() - obtain the pin index of a given auxiliary function 229 * 230 * The caller must hold ptp_clock::pincfg_mux. Drivers do not have 231 * access to that mutex as ptp_clock is an opaque type. However, the 232 * core code acquires the mutex before invoking the driver's 233 * ptp_clock_info::enable() callback, and so drivers may call this 234 * function from that context. 235 * 236 * @ptp: The clock obtained from ptp_clock_register(). 237 * @func: One of the ptp_pin_function enumerated values. 238 * @chan: The particular functional channel to find. 239 * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1, 240 * or -1 if the auxiliary function cannot be found. 241 */ 242 243 int ptp_find_pin(struct ptp_clock *ptp, 244 enum ptp_pin_function func, unsigned int chan); 245 246 /** 247 * ptp_find_pin_unlocked() - wrapper for ptp_find_pin() 248 * 249 * This function acquires the ptp_clock::pincfg_mux mutex before 250 * invoking ptp_find_pin(). Instead of using this function, drivers 251 * should most likely call ptp_find_pin() directly from their 252 * ptp_clock_info::enable() method. 253 * 254 */ 255 256 int ptp_find_pin_unlocked(struct ptp_clock *ptp, 257 enum ptp_pin_function func, unsigned int chan); 258 259 /** 260 * ptp_schedule_worker() - schedule ptp auxiliary work 261 * 262 * @ptp: The clock obtained from ptp_clock_register(). 263 * @delay: number of jiffies to wait before queuing 264 * See kthread_queue_delayed_work() for more info. 265 */ 266 267 int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay); 268 269 /** 270 * ptp_cancel_worker_sync() - cancel ptp auxiliary clock 271 * 272 * @ptp: The clock obtained from ptp_clock_register(). 273 */ 274 void ptp_cancel_worker_sync(struct ptp_clock *ptp); 275 276 #else 277 static inline struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 278 struct device *parent) 279 { return NULL; } 280 static inline int ptp_clock_unregister(struct ptp_clock *ptp) 281 { return 0; } 282 static inline void ptp_clock_event(struct ptp_clock *ptp, 283 struct ptp_clock_event *event) 284 { } 285 static inline int ptp_clock_index(struct ptp_clock *ptp) 286 { return -1; } 287 static inline int ptp_find_pin(struct ptp_clock *ptp, 288 enum ptp_pin_function func, unsigned int chan) 289 { return -1; } 290 static inline int ptp_schedule_worker(struct ptp_clock *ptp, 291 unsigned long delay) 292 { return -EOPNOTSUPP; } 293 static inline void ptp_cancel_worker_sync(struct ptp_clock *ptp) 294 { } 295 296 #endif 297 298 static inline void ptp_read_system_prets(struct ptp_system_timestamp *sts) 299 { 300 if (sts) 301 ktime_get_real_ts64(&sts->pre_ts); 302 } 303 304 static inline void ptp_read_system_postts(struct ptp_system_timestamp *sts) 305 { 306 if (sts) 307 ktime_get_real_ts64(&sts->post_ts); 308 } 309 310 #endif 311