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 * @do_work: Request driver to perform auxiliary (periodic) operations
103 * Driver should return delay of the next auxiliary work scheduling
104 * time (>=0) or negative value in case further scheduling
105 * is not required.
106 *
107 * Drivers should embed their ptp_clock_info within a private
108 * structure, obtaining a reference to it using container_of().
109 *
110 * The callbacks must all return zero on success, non-zero otherwise.
111 */
112
113 struct ptp_clock_info {
114 struct module *owner;
115 char name[16];
116 s32 max_adj;
117 int n_alarm;
118 int n_ext_ts;
119 int n_per_out;
120 int n_pins;
121 int pps;
122 struct ptp_pin_desc *pin_config;
123 int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm);
124 int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
125 int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
126 int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts);
127 int (*getcrosststamp)(struct ptp_clock_info *ptp,
128 struct system_device_crosststamp *cts);
129 int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts);
130 int (*enable)(struct ptp_clock_info *ptp,
131 struct ptp_clock_request *request, int on);
132 int (*verify)(struct ptp_clock_info *ptp, unsigned int pin,
133 enum ptp_pin_function func, unsigned int chan);
134 long (*do_aux_work)(struct ptp_clock_info *ptp);
135 };
136
137 struct ptp_clock;
138
139 enum ptp_clock_events {
140 PTP_CLOCK_ALARM,
141 PTP_CLOCK_EXTTS,
142 PTP_CLOCK_PPS,
143 PTP_CLOCK_PPSUSR,
144 };
145
146 /**
147 * struct ptp_clock_event - decribes a PTP hardware clock event
148 *
149 * @type: One of the ptp_clock_events enumeration values.
150 * @index: Identifies the source of the event.
151 * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only).
152 * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only).
153 */
154
155 struct ptp_clock_event {
156 int type;
157 int index;
158 union {
159 u64 timestamp;
160 struct pps_event_time pps_times;
161 };
162 };
163
164 #if IS_REACHABLE(CONFIG_PTP_1588_CLOCK)
165
166 /**
167 * ptp_clock_register() - register a PTP hardware clock driver
168 *
169 * @info: Structure describing the new clock.
170 * @parent: Pointer to the parent device of the new clock.
171 *
172 * Returns a valid pointer on success or PTR_ERR on failure. If PHC
173 * support is missing at the configuration level, this function
174 * returns NULL, and drivers are expected to gracefully handle that
175 * case separately.
176 */
177
178 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
179 struct device *parent);
180
181 /**
182 * ptp_clock_unregister() - unregister a PTP hardware clock driver
183 *
184 * @ptp: The clock to remove from service.
185 */
186
187 extern int ptp_clock_unregister(struct ptp_clock *ptp);
188
189 /**
190 * ptp_clock_event() - notify the PTP layer about an event
191 *
192 * @ptp: The clock obtained from ptp_clock_register().
193 * @event: Message structure describing the event.
194 */
195
196 extern void ptp_clock_event(struct ptp_clock *ptp,
197 struct ptp_clock_event *event);
198
199 /**
200 * ptp_clock_index() - obtain the device index of a PTP clock
201 *
202 * @ptp: The clock obtained from ptp_clock_register().
203 */
204
205 extern int ptp_clock_index(struct ptp_clock *ptp);
206
207 /**
208 * ptp_find_pin() - obtain the pin index of a given auxiliary function
209 *
210 * @ptp: The clock obtained from ptp_clock_register().
211 * @func: One of the ptp_pin_function enumerated values.
212 * @chan: The particular functional channel to find.
213 * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1,
214 * or -1 if the auxiliary function cannot be found.
215 */
216
217 int ptp_find_pin(struct ptp_clock *ptp,
218 enum ptp_pin_function func, unsigned int chan);
219
220 /**
221 * ptp_schedule_worker() - schedule ptp auxiliary work
222 *
223 * @ptp: The clock obtained from ptp_clock_register().
224 * @delay: number of jiffies to wait before queuing
225 * See kthread_queue_delayed_work() for more info.
226 */
227
228 int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay);
229
230 #else
ptp_clock_register(struct ptp_clock_info * info,struct device * parent)231 static inline struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
232 struct device *parent)
233 { return NULL; }
ptp_clock_unregister(struct ptp_clock * ptp)234 static inline int ptp_clock_unregister(struct ptp_clock *ptp)
235 { return 0; }
ptp_clock_event(struct ptp_clock * ptp,struct ptp_clock_event * event)236 static inline void ptp_clock_event(struct ptp_clock *ptp,
237 struct ptp_clock_event *event)
238 { }
ptp_clock_index(struct ptp_clock * ptp)239 static inline int ptp_clock_index(struct ptp_clock *ptp)
240 { return -1; }
ptp_find_pin(struct ptp_clock * ptp,enum ptp_pin_function func,unsigned int chan)241 static inline int ptp_find_pin(struct ptp_clock *ptp,
242 enum ptp_pin_function func, unsigned int chan)
243 { return -1; }
ptp_schedule_worker(struct ptp_clock * ptp,unsigned long delay)244 static inline int ptp_schedule_worker(struct ptp_clock *ptp,
245 unsigned long delay)
246 { return -EOPNOTSUPP; }
247
248 #endif
249
250 #endif
251
