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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
27struct class *ptp_class;
28
29
30
31static dev_t ptp_devt;
32
33static DEFINE_IDA(ptp_clocks_map);
34
35
36
37static inline int queue_free(struct timestamp_event_queue *q)
38{
39 return PTP_MAX_TIMESTAMPS - queue_cnt(q) - 1;
40}
41
42static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
43 struct ptp_clock_event *src)
44{
45 struct ptp_extts_event *dst;
46 unsigned long flags;
47 s64 seconds;
48 u32 remainder;
49
50 seconds = div_u64_rem(src->timestamp, 1000000000, &remainder);
51
52 spin_lock_irqsave(&queue->lock, flags);
53
54 dst = &queue->buf[queue->tail];
55 dst->index = src->index;
56 dst->t.sec = seconds;
57 dst->t.nsec = remainder;
58
59 if (!queue_free(queue))
60 queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
61
62 queue->tail = (queue->tail + 1) % PTP_MAX_TIMESTAMPS;
63
64 spin_unlock_irqrestore(&queue->lock, flags);
65}
66
67
68
69static int ptp_clock_getres(struct posix_clock *pc, struct timespec64 *tp)
70{
71 tp->tv_sec = 0;
72 tp->tv_nsec = 1;
73 return 0;
74}
75
76static int ptp_clock_settime(struct posix_clock *pc, const struct timespec64 *tp)
77{
78 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
79
80 if (ptp_vclock_in_use(ptp)) {
81 pr_err("ptp: virtual clock in use\n");
82 return -EBUSY;
83 }
84
85 return ptp->info->settime64(ptp->info, tp);
86}
87
88static int ptp_clock_gettime(struct posix_clock *pc, struct timespec64 *tp)
89{
90 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
91 int err;
92
93 if (ptp->info->gettimex64)
94 err = ptp->info->gettimex64(ptp->info, tp, NULL);
95 else
96 err = ptp->info->gettime64(ptp->info, tp);
97 return err;
98}
99
100static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx)
101{
102 struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
103 struct ptp_clock_info *ops;
104 int err = -EOPNOTSUPP;
105
106 if (ptp_vclock_in_use(ptp)) {
107 pr_err("ptp: virtual clock in use\n");
108 return -EBUSY;
109 }
110
111 ops = ptp->info;
112
113 if (tx->modes & ADJ_SETOFFSET) {
114 struct timespec64 ts;
115 ktime_t kt;
116 s64 delta;
117
118 ts.tv_sec = tx->time.tv_sec;
119 ts.tv_nsec = tx->time.tv_usec;
120
121 if (!(tx->modes & ADJ_NANO))
122 ts.tv_nsec *= 1000;
123
124 if ((unsigned long) ts.tv_nsec >= NSEC_PER_SEC)
125 return -EINVAL;
126
127 kt = timespec64_to_ktime(ts);
128 delta = ktime_to_ns(kt);
129 err = ops->adjtime(ops, delta);
130 } else if (tx->modes & ADJ_FREQUENCY) {
131 long ppb = scaled_ppm_to_ppb(tx->freq);
132 if (ppb > ops->max_adj || ppb < -ops->max_adj)
133 return -ERANGE;
134 if (ops->adjfine)
135 err = ops->adjfine(ops, tx->freq);
136 else
137 err = ops->adjfreq(ops, ppb);
138 ptp->dialed_frequency = tx->freq;
139 } else if (tx->modes & ADJ_OFFSET) {
140 if (ops->adjphase) {
141 s32 offset = tx->offset;
142
143 if (!(tx->modes & ADJ_NANO))
144 offset *= NSEC_PER_USEC;
145
146 err = ops->adjphase(ops, offset);
147 }
148 } else if (tx->modes == 0) {
149 tx->freq = ptp->dialed_frequency;
150 err = 0;
151 }
152
153 return err;
154}
155
156static struct posix_clock_operations ptp_clock_ops = {
157 .owner = THIS_MODULE,
158 .clock_adjtime = ptp_clock_adjtime,
159 .clock_gettime = ptp_clock_gettime,
160 .clock_getres = ptp_clock_getres,
161 .clock_settime = ptp_clock_settime,
162 .ioctl = ptp_ioctl,
163 .open = ptp_open,
164 .poll = ptp_poll,
165 .read = ptp_read,
166};
167
168static void ptp_clock_release(struct device *dev)
169{
170 struct ptp_clock *ptp = container_of(dev, struct ptp_clock, dev);
171
172 ptp_cleanup_pin_groups(ptp);
173 kfree(ptp->vclock_index);
174 mutex_destroy(&ptp->tsevq_mux);
175 mutex_destroy(&ptp->pincfg_mux);
176 mutex_destroy(&ptp->n_vclocks_mux);
177 ida_simple_remove(&ptp_clocks_map, ptp->index);
178 kfree(ptp);
179}
180
181static void ptp_aux_kworker(struct kthread_work *work)
182{
183 struct ptp_clock *ptp = container_of(work, struct ptp_clock,
184 aux_work.work);
185 struct ptp_clock_info *info = ptp->info;
186 long delay;
187
188 delay = info->do_aux_work(info);
189
190 if (delay >= 0)
191 kthread_queue_delayed_work(ptp->kworker, &ptp->aux_work, delay);
192}
193
194
195
196struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
197 struct device *parent)
198{
199 struct ptp_clock *ptp;
200 int err = 0, index, major = MAJOR(ptp_devt);
201 size_t size;
202
203 if (info->n_alarm > PTP_MAX_ALARMS)
204 return ERR_PTR(-EINVAL);
205
206
207 err = -ENOMEM;
208 ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
209 if (ptp == NULL)
210 goto no_memory;
211
212 index = ida_simple_get(&ptp_clocks_map, 0, MINORMASK + 1, GFP_KERNEL);
213 if (index < 0) {
214 err = index;
215 goto no_slot;
216 }
217
218 ptp->clock.ops = ptp_clock_ops;
219 ptp->info = info;
220 ptp->devid = MKDEV(major, index);
221 ptp->index = index;
222 spin_lock_init(&ptp->tsevq.lock);
223 mutex_init(&ptp->tsevq_mux);
224 mutex_init(&ptp->pincfg_mux);
225 mutex_init(&ptp->n_vclocks_mux);
226 init_waitqueue_head(&ptp->tsev_wq);
227
228 if (ptp->info->do_aux_work) {
229 kthread_init_delayed_work(&ptp->aux_work, ptp_aux_kworker);
230 ptp->kworker = kthread_create_worker(0, "ptp%d", ptp->index);
231 if (IS_ERR(ptp->kworker)) {
232 err = PTR_ERR(ptp->kworker);
233 pr_err("failed to create ptp aux_worker %d\n", err);
234 goto kworker_err;
235 }
236 }
237
238
239 if (parent && parent->class && parent->class->name &&
240 strcmp(parent->class->name, "ptp") == 0)
241 ptp->is_virtual_clock = true;
242
243 if (!ptp->is_virtual_clock) {
244 ptp->max_vclocks = PTP_DEFAULT_MAX_VCLOCKS;
245
246 size = sizeof(int) * ptp->max_vclocks;
247 ptp->vclock_index = kzalloc(size, GFP_KERNEL);
248 if (!ptp->vclock_index) {
249 err = -ENOMEM;
250 goto no_mem_for_vclocks;
251 }
252 }
253
254 err = ptp_populate_pin_groups(ptp);
255 if (err)
256 goto no_pin_groups;
257
258
259 if (info->pps) {
260 struct pps_source_info pps;
261 memset(&pps, 0, sizeof(pps));
262 snprintf(pps.name, PPS_MAX_NAME_LEN, "ptp%d", index);
263 pps.mode = PTP_PPS_MODE;
264 pps.owner = info->owner;
265 ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
266 if (IS_ERR(ptp->pps_source)) {
267 err = PTR_ERR(ptp->pps_source);
268 pr_err("failed to register pps source\n");
269 goto no_pps;
270 }
271 ptp->pps_source->lookup_cookie = ptp;
272 }
273
274
275 device_initialize(&ptp->dev);
276 ptp->dev.devt = ptp->devid;
277 ptp->dev.class = ptp_class;
278 ptp->dev.parent = parent;
279 ptp->dev.groups = ptp->pin_attr_groups;
280 ptp->dev.release = ptp_clock_release;
281 dev_set_drvdata(&ptp->dev, ptp);
282 dev_set_name(&ptp->dev, "ptp%d", ptp->index);
283
284
285 err = posix_clock_register(&ptp->clock, &ptp->dev);
286 if (err) {
287 if (ptp->pps_source)
288 pps_unregister_source(ptp->pps_source);
289
290 if (ptp->kworker)
291 kthread_destroy_worker(ptp->kworker);
292
293 put_device(&ptp->dev);
294
295 pr_err("failed to create posix clock\n");
296 return ERR_PTR(err);
297 }
298
299 return ptp;
300
301no_pps:
302 ptp_cleanup_pin_groups(ptp);
303no_pin_groups:
304 kfree(ptp->vclock_index);
305no_mem_for_vclocks:
306 if (ptp->kworker)
307 kthread_destroy_worker(ptp->kworker);
308kworker_err:
309 mutex_destroy(&ptp->tsevq_mux);
310 mutex_destroy(&ptp->pincfg_mux);
311 mutex_destroy(&ptp->n_vclocks_mux);
312 ida_simple_remove(&ptp_clocks_map, index);
313no_slot:
314 kfree(ptp);
315no_memory:
316 return ERR_PTR(err);
317}
318EXPORT_SYMBOL(ptp_clock_register);
319
320int ptp_clock_unregister(struct ptp_clock *ptp)
321{
322 if (ptp_vclock_in_use(ptp)) {
323 pr_err("ptp: virtual clock in use\n");
324 return -EBUSY;
325 }
326
327 ptp->defunct = 1;
328 wake_up_interruptible(&ptp->tsev_wq);
329
330 if (ptp->kworker) {
331 kthread_cancel_delayed_work_sync(&ptp->aux_work);
332 kthread_destroy_worker(ptp->kworker);
333 }
334
335
336 if (ptp->pps_source)
337 pps_unregister_source(ptp->pps_source);
338
339 posix_clock_unregister(&ptp->clock);
340
341 return 0;
342}
343EXPORT_SYMBOL(ptp_clock_unregister);
344
345void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
346{
347 struct pps_event_time evt;
348
349 switch (event->type) {
350
351 case PTP_CLOCK_ALARM:
352 break;
353
354 case PTP_CLOCK_EXTTS:
355 enqueue_external_timestamp(&ptp->tsevq, event);
356 wake_up_interruptible(&ptp->tsev_wq);
357 break;
358
359 case PTP_CLOCK_PPS:
360 pps_get_ts(&evt);
361 pps_event(ptp->pps_source, &evt, PTP_PPS_EVENT, NULL);
362 break;
363
364 case PTP_CLOCK_PPSUSR:
365 pps_event(ptp->pps_source, &event->pps_times,
366 PTP_PPS_EVENT, NULL);
367 break;
368 }
369}
370EXPORT_SYMBOL(ptp_clock_event);
371
372int ptp_clock_index(struct ptp_clock *ptp)
373{
374 return ptp->index;
375}
376EXPORT_SYMBOL(ptp_clock_index);
377
378int ptp_find_pin(struct ptp_clock *ptp,
379 enum ptp_pin_function func, unsigned int chan)
380{
381 struct ptp_pin_desc *pin = NULL;
382 int i;
383
384 for (i = 0; i < ptp->info->n_pins; i++) {
385 if (ptp->info->pin_config[i].func == func &&
386 ptp->info->pin_config[i].chan == chan) {
387 pin = &ptp->info->pin_config[i];
388 break;
389 }
390 }
391
392 return pin ? i : -1;
393}
394EXPORT_SYMBOL(ptp_find_pin);
395
396int ptp_find_pin_unlocked(struct ptp_clock *ptp,
397 enum ptp_pin_function func, unsigned int chan)
398{
399 int result;
400
401 mutex_lock(&ptp->pincfg_mux);
402
403 result = ptp_find_pin(ptp, func, chan);
404
405 mutex_unlock(&ptp->pincfg_mux);
406
407 return result;
408}
409EXPORT_SYMBOL(ptp_find_pin_unlocked);
410
411int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay)
412{
413 return kthread_mod_delayed_work(ptp->kworker, &ptp->aux_work, delay);
414}
415EXPORT_SYMBOL(ptp_schedule_worker);
416
417void ptp_cancel_worker_sync(struct ptp_clock *ptp)
418{
419 kthread_cancel_delayed_work_sync(&ptp->aux_work);
420}
421EXPORT_SYMBOL(ptp_cancel_worker_sync);
422
423
424
425static void __exit ptp_exit(void)
426{
427 class_destroy(ptp_class);
428 unregister_chrdev_region(ptp_devt, MINORMASK + 1);
429 ida_destroy(&ptp_clocks_map);
430}
431
432static int __init ptp_init(void)
433{
434 int err;
435
436 ptp_class = class_create(THIS_MODULE, "ptp");
437 if (IS_ERR(ptp_class)) {
438 pr_err("ptp: failed to allocate class\n");
439 return PTR_ERR(ptp_class);
440 }
441
442 err = alloc_chrdev_region(&ptp_devt, 0, MINORMASK + 1, "ptp");
443 if (err < 0) {
444 pr_err("ptp: failed to allocate device region\n");
445 goto no_region;
446 }
447
448 ptp_class->dev_groups = ptp_groups;
449 pr_info("PTP clock support registered\n");
450 return 0;
451
452no_region:
453 class_destroy(ptp_class);
454 return err;
455}
456
457subsys_initcall(ptp_init);
458module_exit(ptp_exit);
459
460MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
461MODULE_DESCRIPTION("PTP clocks support");
462MODULE_LICENSE("GPL");
463
