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7#include <linux/idr.h>
8#include <linux/device.h>
9#include <linux/err.h>
10#include <linux/init.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/posix-clock.h>
14#include <linux/pps_kernel.h>
15#include <linux/slab.h>
16#include <linux/syscalls.h>
17#include <linux/uaccess.h>
18#include <uapi/linux/sched/types.h>
19
20#include "ptp_private.h"
21
22#define PTP_MAX_ALARMS 4
23#define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT)
24#define PTP_PPS_EVENT PPS_CAPTUREASSERT
25#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
26
27
28
29static dev_t ptp_devt;
30static struct class *ptp_class;
31
32static DEFINE_IDA(ptp_clocks_map);
33
34
35
36static inline int queue_free(struct timestamp_event_queue *q)
37{
38 return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
39}
40
41static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
42 struct ptp_clock_event *src)
43{
44 struct ptp_extts_event *dst;
45 unsigned long flags;
46 s64 seconds;
47 u32 remainder;
48
49 seconds = div_u64_rem(src->timestamp, 1000000000, &remainder);
50
51 spin_lock_irqsave(&queue->lock, flags);
52
53 dst = &queue->buf[queue->tail];
54 dst->index = src->index;
55 dst->t.sec = seconds;
56 dst->t.nsec = remainder;
57
58 if (!queue_free(queue))
59 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
60
61 queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
62
63 spin_unlock_irqrestore(&queue->lock, flags);
64}
65
66s32 scaled_ppm_to_ppb(long ppm)
67{
68
69
70
71
72
73
74
75
76
77
78
79
80 s64 ppb = 1 + ppm;
81 ppb *= 125;
82 ppb >>= 13;
83 return (s32) ppb;
84}
85EXPORT_SYMBOL(scaled_ppm_to_ppb);
86
87
88
89static int ptp_clock_getres(struct posix_clock *pc, struct timespec64 *tp)
90{
91 tp->tv_sec = 0;
92 tp->tv_nsec = 1;
93 return 0;
94}
95
96static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp)
97{
98 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
99
100 return ptp->info->settime64(ptp->info, tp);
101}
102
103static int ptp_clock_gettime(struct posix_clock *pc, struct timespec64 *tp)
104{
105 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
106 int err;
107
108 if (ptp->info->gettimex64)
109 err = ptp->info->gettimex64(ptp->info, tp, NULL);
110 else
111 err = ptp->info->gettime64(ptp->info, tp);
112 return err;
113}
114
115static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx)
116{
117 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
118 struct ptp_clock_info *ops;
119 int err = -EOPNOTSUPP;
120
121 ops = ptp->info;
122
123 if (tx->modes & ADJ_SETOFFSET) {
124 struct timespec64 ts;
125 ktime_t kt;
126 s64 delta;
127
128 ts.tv_sec = tx->time.tv_sec;
129 ts.tv_nsec = tx->time.tv_usec;
130
131 if (!(tx->modes & ADJ_NANO))
132 ts.tv_nsec *= 1000;
133
134 if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC)
135 return -EINVAL;
136
137 kt = timespec64_to_ktime(ts);
138 delta = ktime_to_ns(kt);
139 err = ops->adjtime(ops, delta);
140 } else if (tx->modes & ADJ_FREQUENCY) {
141 s32 ppb = scaled_ppm_to_ppb(tx->freq);
142 if (ppb > ops->max_adj || ppb < -ops->max_adj)
143 return -ERANGE;
144 if (ops->adjfine)
145 err = ops->adjfine(ops, tx->freq);
146 else
147 err = ops->adjfreq(ops, ppb);
148 ptp->dialed_frequency = tx->freq;
149 } else if (tx->modes == 0) {
150 tx->freq = ptp->dialed_frequency;
151 err = 0;
152 }
153
154 return err;
155}
156
157static struct posix_clock_operations ptp_clock_ops = {
158 .owner = THIS_MODULE,
159 .clock_adjtime = ptp_clock_adjtime,
160 .clock_gettime = ptp_clock_gettime,
161 .clock_getres = ptp_clock_getres,
162 .clock_settime = ptp_clock_settime,
163 .ioctl = ptp_ioctl,
164 .open = ptp_open,
165 .poll = ptp_poll,
166 .read = ptp_read,
167};
168
169static void ptp_clock_release(struct device *dev)
170{
171 struct ptp_clock *ptp = container_of(dev, struct ptp_clock, dev);
172
173 ptp_cleanup_pin_groups(ptp);
174 mutex_destroy(&ptp->tsevq_mux);
175 mutex_destroy(&ptp->pincfg_mux);
176 ida_simple_remove(&ptp_clocks_map, ptp->index);
177 kfree(ptp);
178}
179
180static void ptp_aux_kworker(struct kthread_work *work)
181{
182 struct ptp_clock *ptp = container_of(work, struct ptp_clock,
183 aux_work.work);
184 struct ptp_clock_info *info = ptp->info;
185 long delay;
186
187 delay = info->do_aux_work(info);
188
189 if (delay >= 0)
190 kthread_queue_delayed_work(ptp->kworker, &ptp->aux_work, delay);
191}
192
193
194
195struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
196 struct device *parent)
197{
198 struct ptp_clock *ptp;
199 int err = 0, index, major = MAJOR(ptp_devt);
200
201 if (info->n_alarm > PTP_MAX_ALARMS)
202 return ERR_PTR(-EINVAL);
203
204
205 err = -ENOMEM;
206 ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
207 if (ptp == NULL)
208 goto no_memory;
209
210 index = ida_simple_get(&ptp_clocks_map, 0, MINORMASK + 1, GFP_KERNEL);
211 if (index < 0) {
212 err = index;
213 goto no_slot;
214 }
215
216 ptp->clock.ops = ptp_clock_ops;
217 ptp->info = info;
218 ptp->devid = MKDEV(major, index);
219 ptp->index = index;
220 spin_lock_init(&ptp->tsevq.lock);
221 mutex_init(&ptp->tsevq_mux);
222 mutex_init(&ptp->pincfg_mux);
223 init_waitqueue_head(&ptp->tsev_wq);
224
225 if (ptp->info->do_aux_work) {
226 kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker);
227 ptp->kworker = kthread_create_worker(0, "ptp%d", ptp->index);
228 if (IS_ERR(ptp->kworker)) {
229 err = PTR_ERR(ptp->kworker);
230 pr_err("failed to create ptp aux_worker %d\n", err);
231 goto kworker_err;
232 }
233 }
234
235 err = ptp_populate_pin_groups(ptp);
236 if (err)
237 goto no_pin_groups;
238
239
240 if (info->pps) {
241 struct pps_source_info pps;
242 memset(&pps, 0, sizeof(pps));
243 snprintf(pps.name, PPS_MAX_NAME_LEN, "ptp%d", index);
244 pps.mode = PTP_PPS_MODE;
245 pps.owner = info->owner;
246 ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
247 if (IS_ERR(ptp->pps_source)) {
248 err = PTR_ERR(ptp->pps_source);
249 pr_err("failed to register pps source\n");
250 goto no_pps;
251 }
252 }
253
254
255 device_initialize(&ptp->dev);
256 ptp->dev.devt = ptp->devid;
257 ptp->dev.class = ptp_class;
258 ptp->dev.parent = parent;
259 ptp->dev.groups = ptp->pin_attr_groups;
260 ptp->dev.release = ptp_clock_release;
261 dev_set_drvdata(&ptp->dev, ptp);
262 dev_set_name(&ptp->dev, "ptp%d", ptp->index);
263
264
265 err = posix_clock_register(&ptp->clock, &ptp->dev);
266 if (err) {
267 pr_err("failed to create posix clock\n");
268 goto no_clock;
269 }
270
271 return ptp;
272
273no_clock:
274 if (ptp->pps_source)
275 pps_unregister_source(ptp->pps_source);
276no_pps:
277 ptp_cleanup_pin_groups(ptp);
278no_pin_groups:
279 if (ptp->kworker)
280 kthread_destroy_worker(ptp->kworker);
281kworker_err:
282 mutex_destroy(&ptp->tsevq_mux);
283 mutex_destroy(&ptp->pincfg_mux);
284 ida_simple_remove(&ptp_clocks_map, index);
285no_slot:
286 kfree(ptp);
287no_memory:
288 return ERR_PTR(err);
289}
290EXPORT_SYMBOL(ptp_clock_register);
291
292int ptp_clock_unregister(struct ptp_clock *ptp)
293{
294 ptp->defunct = 1;
295 wake_up_interruptible(&ptp->tsev_wq);
296
297 if (ptp->kworker) {
298 kthread_cancel_delayed_work_sync(&ptp->aux_work);
299 kthread_destroy_worker(ptp->kworker);
300 }
301
302
303 if (ptp->pps_source)
304 pps_unregister_source(ptp->pps_source);
305
306 posix_clock_unregister(&ptp->clock);
307
308 return 0;
309}
310EXPORT_SYMBOL(ptp_clock_unregister);
311
312void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
313{
314 struct pps_event_time evt;
315
316 switch (event->type) {
317
318 case PTP_CLOCK_ALARM:
319 break;
320
321 case PTP_CLOCK_EXTTS:
322 enqueue_external_timestamp(&ptp->tsevq, event);
323 wake_up_interruptible(&ptp->tsev_wq);
324 break;
325
326 case PTP_CLOCK_PPS:
327 pps_get_ts(&evt);
328 pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
329 break;
330
331 case PTP_CLOCK_PPSUSR:
332 pps_event(ptp->pps_source, &event->pps_times,
333 PTP_PPS_EVENT, NULL);
334 break;
335 }
336}
337EXPORT_SYMBOL(ptp_clock_event);
338
339int ptp_clock_index(struct ptp_clock *ptp)
340{
341 return ptp->index;
342}
343EXPORT_SYMBOL(ptp_clock_index);
344
345int ptp_find_pin(struct ptp_clock *ptp,
346 enum ptp_pin_function func, unsigned int chan)
347{
348 struct ptp_pin_desc *pin = NULL;
349 int i;
350
351 mutex_lock(&ptp->pincfg_mux);
352 for (i = 0; i < ptp->info->n_pins; i++) {
353 if (ptp->info->pin_config[i].func == func &&
354 ptp->info->pin_config[i].chan == chan) {
355 pin = &ptp->info->pin_config[i];
356 break;
357 }
358 }
359 mutex_unlock(&ptp->pincfg_mux);
360
361 return pin ? i : -1;
362}
363EXPORT_SYMBOL(ptp_find_pin);
364
365int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay)
366{
367 return kthread_mod_delayed_work(ptp->kworker, &ptp->aux_work, delay);
368}
369EXPORT_SYMBOL(ptp_schedule_worker);
370
371void ptp_cancel_worker_sync(struct ptp_clock *ptp)
372{
373 kthread_cancel_delayed_work_sync(&ptp->aux_work);
374}
375EXPORT_SYMBOL(ptp_cancel_worker_sync);
376
377
378
379static void __exit ptp_exit(void)
380{
381 class_destroy(ptp_class);
382 unregister_chrdev_region(ptp_devt, MINORMASK + 1);
383 ida_destroy(&ptp_clocks_map);
384}
385
386static int __init ptp_init(void)
387{
388 int err;
389
390 ptp_class = class_create(THIS_MODULE, "ptp");
391 if (IS_ERR(ptp_class)) {
392 pr_err("ptp: failed to allocate class\n");
393 return PTR_ERR(ptp_class);
394 }
395
396 err = alloc_chrdev_region(&ptp_devt, 0, MINORMASK + 1, "ptp");
397 if (err < 0) {
398 pr_err("ptp: failed to allocate device region\n");
399 goto no_region;
400 }
401
402 ptp_class->dev_groups = ptp_groups;
403 pr_info("PTP clock support registered\n");
404 return 0;
405
406no_region:
407 class_destroy(ptp_class);
408 return err;
409}
410
411subsys_initcall(ptp_init);
412module_exit(ptp_exit);
413
414MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
415MODULE_DESCRIPTION("PTP clocks support");
416MODULE_LICENSE("GPL");
417
