1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * PTP 1588 clock support
5 * Copyright (C) 2010 OMICRON electronics GmbH
8 #ifndef _PTP_CLOCK_KERNEL_H_
9 #define _PTP_CLOCK_KERNEL_H_
11 #include <linux/device.h>
12 #include <linux/pps_kernel.h>
13 #include <linux/ptp_clock.h>
14 #include <linux/timecounter.h>
16 #define PTP_CLOCK_NAME_LEN 32
18 * struct ptp_clock_request - request PTP clock event
20 * @type: The type of the request.
21 * EXTTS: Configure external trigger timestamping
22 * PEROUT: Configure periodic output signal (e.g. PPS)
23 * PPS: trigger internal PPS event for input
24 * into kernel PPS subsystem
25 * @extts: describes configuration for external trigger timestamping.
26 * This is only valid when event == PTP_CLK_REQ_EXTTS.
27 * @perout: describes configuration for periodic output.
28 * This is only valid when event == PTP_CLK_REQ_PEROUT.
31 struct ptp_clock_request {
38 struct ptp_extts_request extts;
39 struct ptp_perout_request perout;
43 struct system_device_crosststamp;
46 * struct ptp_system_timestamp - system time corresponding to a PHC timestamp
48 struct ptp_system_timestamp {
49 struct timespec64 pre_ts;
50 struct timespec64 post_ts;
54 * struct ptp_clock_info - describes a PTP hardware clock
56 * @owner: The clock driver should set to THIS_MODULE.
57 * @name: A short "friendly name" to identify the clock and to
58 * help distinguish PHY based devices from MAC based ones.
59 * The string is not meant to be a unique id.
60 * @max_adj: The maximum possible frequency adjustment, in parts per billon.
61 * @n_alarm: The number of programmable alarms.
62 * @n_ext_ts: The number of external time stamp channels.
63 * @n_per_out: The number of programmable periodic signals.
64 * @n_pins: The number of programmable pins.
65 * @pps: Indicates whether the clock supports a PPS callback.
66 * @pin_config: Array of length 'n_pins'. If the number of
67 * programmable pins is nonzero, then drivers must
68 * allocate and initialize this array.
72 * @adjfine: Adjusts the frequency of the hardware clock.
73 * parameter scaled_ppm: Desired frequency offset from
74 * nominal frequency in parts per million, but with a
75 * 16 bit binary fractional field.
77 * @adjfreq: Adjusts the frequency of the hardware clock.
78 * This method is deprecated. New drivers should implement
79 * the @adjfine method instead.
80 * parameter delta: Desired frequency offset from nominal frequency
81 * in parts per billion
83 * @adjphase: Adjusts the phase offset of the hardware clock.
84 * parameter delta: Desired change in nanoseconds.
86 * @adjtime: Shifts the time of the hardware clock.
87 * parameter delta: Desired change in nanoseconds.
89 * @gettime64: Reads the current time from the hardware clock.
90 * This method is deprecated. New drivers should implement
91 * the @gettimex64 method instead.
92 * parameter ts: Holds the result.
94 * @gettimex64: Reads the current time from the hardware clock and optionally
95 * also the system clock.
96 * parameter ts: Holds the PHC timestamp.
97 * parameter sts: If not NULL, it holds a pair of timestamps from
98 * the system clock. The first reading is made right before
99 * reading the lowest bits of the PHC timestamp and the second
100 * reading immediately follows that.
102 * @getcrosststamp: Reads the current time from the hardware clock and
103 * system clock simultaneously.
104 * parameter cts: Contains timestamp (device,system) pair,
105 * where system time is realtime and monotonic.
107 * @settime64: Set the current time on the hardware clock.
108 * parameter ts: Time value to set.
110 * @enable: Request driver to enable or disable an ancillary feature.
111 * parameter request: Desired resource to enable or disable.
112 * parameter on: Caller passes one to enable or zero to disable.
114 * @verify: Confirm that a pin can perform a given function. The PTP
115 * Hardware Clock subsystem maintains the 'pin_config'
116 * array on behalf of the drivers, but the PHC subsystem
117 * assumes that every pin can perform every function. This
118 * hook gives drivers a way of telling the core about
119 * limitations on specific pins. This function must return
120 * zero if the function can be assigned to this pin, and
122 * parameter pin: index of the pin in question.
123 * parameter func: the desired function to use.
124 * parameter chan: the function channel index to use.
126 * @do_aux_work: Request driver to perform auxiliary (periodic) operations
127 * Driver should return delay of the next auxiliary work
128 * scheduling time (>=0) or negative value in case further
129 * scheduling is not required.
131 * Drivers should embed their ptp_clock_info within a private
132 * structure, obtaining a reference to it using container_of().
134 * The callbacks must all return zero on success, non-zero otherwise.
137 struct ptp_clock_info {
138 struct module *owner;
139 char name[PTP_CLOCK_NAME_LEN];
146 struct ptp_pin_desc *pin_config;
147 int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm);
148 int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
149 int (*adjphase)(struct ptp_clock_info *ptp, s32 phase);
150 int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
151 int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts);
152 int (*gettimex64)(struct ptp_clock_info *ptp, struct timespec64 *ts,
153 struct ptp_system_timestamp *sts);
154 int (*getcrosststamp)(struct ptp_clock_info *ptp,
155 struct system_device_crosststamp *cts);
156 int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts);
157 int (*enable)(struct ptp_clock_info *ptp,
158 struct ptp_clock_request *request, int on);
159 int (*verify)(struct ptp_clock_info *ptp, unsigned int pin,
160 enum ptp_pin_function func, unsigned int chan);
161 long (*do_aux_work)(struct ptp_clock_info *ptp);
166 enum ptp_clock_events {
174 * struct ptp_clock_event - decribes a PTP hardware clock event
176 * @type: One of the ptp_clock_events enumeration values.
177 * @index: Identifies the source of the event.
178 * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
179 * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
182 struct ptp_clock_event {
187 struct pps_event_time pps_times;
192 * scaled_ppm_to_ppb() - convert scaled ppm to ppb
194 * @ppm: Parts per million, but with a 16 bit binary fractional field
196 static inline long scaled_ppm_to_ppb(long ppm)
199 * The 'freq' field in the 'struct timex' is in parts per
200 * million, but with a 16 bit binary fractional field.
202 * We want to calculate
204 * ppb = scaled_ppm * 1000 / 2^16
206 * which simplifies to
208 * ppb = scaled_ppm * 125 / 2^13
217 #if IS_REACHABLE(CONFIG_PTP_1588_CLOCK)
220 * ptp_clock_register() - register a PTP hardware clock driver
222 * @info: Structure describing the new clock.
223 * @parent: Pointer to the parent device of the new clock.
225 * Returns a valid pointer on success or PTR_ERR on failure. If PHC
226 * support is missing at the configuration level, this function
227 * returns NULL, and drivers are expected to gracefully handle that
231 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
232 struct device *parent);
235 * ptp_clock_unregister() - unregister a PTP hardware clock driver
237 * @ptp: The clock to remove from service.
240 extern int ptp_clock_unregister(struct ptp_clock *ptp);
243 * ptp_clock_event() - notify the PTP layer about an event
245 * @ptp: The clock obtained from ptp_clock_register().
246 * @event: Message structure describing the event.
249 extern void ptp_clock_event(struct ptp_clock *ptp,
250 struct ptp_clock_event *event);
253 * ptp_clock_index() - obtain the device index of a PTP clock
255 * @ptp: The clock obtained from ptp_clock_register().
258 extern int ptp_clock_index(struct ptp_clock *ptp);
261 * ptp_find_pin() - obtain the pin index of a given auxiliary function
263 * The caller must hold ptp_clock::pincfg_mux. Drivers do not have
264 * access to that mutex as ptp_clock is an opaque type. However, the
265 * core code acquires the mutex before invoking the driver's
266 * ptp_clock_info::enable() callback, and so drivers may call this
267 * function from that context.
269 * @ptp: The clock obtained from ptp_clock_register().
270 * @func: One of the ptp_pin_function enumerated values.
271 * @chan: The particular functional channel to find.
272 * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1,
273 * or -1 if the auxiliary function cannot be found.
276 int ptp_find_pin(struct ptp_clock *ptp,
277 enum ptp_pin_function func, unsigned int chan);
280 * ptp_find_pin_unlocked() - wrapper for ptp_find_pin()
282 * This function acquires the ptp_clock::pincfg_mux mutex before
283 * invoking ptp_find_pin(). Instead of using this function, drivers
284 * should most likely call ptp_find_pin() directly from their
285 * ptp_clock_info::enable() method.
289 int ptp_find_pin_unlocked(struct ptp_clock *ptp,
290 enum ptp_pin_function func, unsigned int chan);
293 * ptp_schedule_worker() - schedule ptp auxiliary work
295 * @ptp: The clock obtained from ptp_clock_register().
296 * @delay: number of jiffies to wait before queuing
297 * See kthread_queue_delayed_work() for more info.
300 int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay);
303 * ptp_cancel_worker_sync() - cancel ptp auxiliary clock
305 * @ptp: The clock obtained from ptp_clock_register().
307 void ptp_cancel_worker_sync(struct ptp_clock *ptp);
310 static inline struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
311 struct device *parent)
313 static inline int ptp_clock_unregister(struct ptp_clock *ptp)
315 static inline void ptp_clock_event(struct ptp_clock *ptp,
316 struct ptp_clock_event *event)
318 static inline int ptp_clock_index(struct ptp_clock *ptp)
320 static inline int ptp_find_pin(struct ptp_clock *ptp,
321 enum ptp_pin_function func, unsigned int chan)
323 static inline int ptp_schedule_worker(struct ptp_clock *ptp,
325 { return -EOPNOTSUPP; }
326 static inline void ptp_cancel_worker_sync(struct ptp_clock *ptp)
331 static inline void ptp_read_system_prets(struct ptp_system_timestamp *sts)
334 ktime_get_real_ts64(&sts->pre_ts);
337 static inline void ptp_read_system_postts(struct ptp_system_timestamp *sts)
340 ktime_get_real_ts64(&sts->post_ts);