1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PTP 1588 clock support - character device implementation.
4 *
5 * Copyright (C) 2010 OMICRON electronics GmbH
6 */
7#include <linux/module.h>
8#include <linux/posix-clock.h>
9#include <linux/poll.h>
10#include <linux/sched.h>
11#include <linux/slab.h>
12#include <linux/timekeeping.h>
13#include <linux/debugfs.h>
14
15#include <linux/nospec.h>
16
17#include "ptp_private.h"
18
19static int ptp_disable_pinfunc(struct ptp_clock_info *ops,
20 enum ptp_pin_function func, unsigned int chan)
21{
22 struct ptp_clock_request rq;
23 int err = 0;
24
25 memset(&rq, 0, sizeof(rq));
26
27 switch (func) {
28 case PTP_PF_NONE:
29 break;
30 case PTP_PF_EXTTS:
31 rq.type = PTP_CLK_REQ_EXTTS;
32 rq.extts.index = chan;
33 err = ops->enable(ops, &rq, 0);
34 break;
35 case PTP_PF_PEROUT:
36 rq.type = PTP_CLK_REQ_PEROUT;
37 rq.perout.index = chan;
38 err = ops->enable(ops, &rq, 0);
39 break;
40 case PTP_PF_PHYSYNC:
41 break;
42 default:
43 return -EINVAL;
44 }
45
46 return err;
47}
48
49int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin,
50 enum ptp_pin_function func, unsigned int chan)
51{
52 struct ptp_clock_info *info = ptp->info;
53 struct ptp_pin_desc *pin1 = NULL, *pin2 = &info->pin_config[pin];
54 unsigned int i;
55
56 /* Check to see if any other pin previously had this function. */
57 for (i = 0; i < info->n_pins; i++) {
58 if (info->pin_config[i].func == func &&
59 info->pin_config[i].chan == chan) {
60 pin1 = &info->pin_config[i];
61 break;
62 }
63 }
64 if (pin1 && i == pin)
65 return 0;
66
67 /* Check the desired function and channel. */
68 switch (func) {
69 case PTP_PF_NONE:
70 break;
71 case PTP_PF_EXTTS:
72 if (chan >= info->n_ext_ts)
73 return -EINVAL;
74 break;
75 case PTP_PF_PEROUT:
76 if (chan >= info->n_per_out)
77 return -EINVAL;
78 break;
79 case PTP_PF_PHYSYNC:
80 if (chan != 0)
81 return -EINVAL;
82 break;
83 default:
84 return -EINVAL;
85 }
86
87 if (info->verify(info, pin, func, chan)) {
88 pr_err("driver cannot use function %u on pin %u\n", func, chan);
89 return -EOPNOTSUPP;
90 }
91
92 /* Disable whatever function was previously assigned. */
93 if (pin1) {
94 ptp_disable_pinfunc(ops: info, func, chan);
95 pin1->func = PTP_PF_NONE;
96 pin1->chan = 0;
97 }
98 ptp_disable_pinfunc(ops: info, func: pin2->func, chan: pin2->chan);
99 pin2->func = func;
100 pin2->chan = chan;
101
102 return 0;
103}
104
105int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode)
106{
107 struct ptp_clock *ptp =
108 container_of(pccontext->clk, struct ptp_clock, clock);
109 struct timestamp_event_queue *queue;
110 char debugfsname[32];
111 unsigned long flags;
112
113 queue = kzalloc(size: sizeof(*queue), GFP_KERNEL);
114 if (!queue)
115 return -EINVAL;
116 queue->mask = bitmap_alloc(PTP_MAX_CHANNELS, GFP_KERNEL);
117 if (!queue->mask) {
118 kfree(objp: queue);
119 return -EINVAL;
120 }
121 bitmap_set(map: queue->mask, start: 0, PTP_MAX_CHANNELS);
122 spin_lock_init(&queue->lock);
123 spin_lock_irqsave(&ptp->tsevqs_lock, flags);
124 list_add_tail(new: &queue->qlist, head: &ptp->tsevqs);
125 spin_unlock_irqrestore(lock: &ptp->tsevqs_lock, flags);
126 pccontext->private_clkdata = queue;
127
128 /* Debugfs contents */
129 sprintf(buf: debugfsname, fmt: "0x%p", queue);
130 queue->debugfs_instance =
131 debugfs_create_dir(name: debugfsname, parent: ptp->debugfs_root);
132 queue->dfs_bitmap.array = (u32 *)queue->mask;
133 queue->dfs_bitmap.n_elements =
134 DIV_ROUND_UP(PTP_MAX_CHANNELS, BITS_PER_BYTE * sizeof(u32));
135 debugfs_create_u32_array(name: "mask", mode: 0444, parent: queue->debugfs_instance,
136 array: &queue->dfs_bitmap);
137
138 return 0;
139}
140
141int ptp_release(struct posix_clock_context *pccontext)
142{
143 struct timestamp_event_queue *queue = pccontext->private_clkdata;
144 unsigned long flags;
145 struct ptp_clock *ptp =
146 container_of(pccontext->clk, struct ptp_clock, clock);
147
148 debugfs_remove(dentry: queue->debugfs_instance);
149 pccontext->private_clkdata = NULL;
150 spin_lock_irqsave(&ptp->tsevqs_lock, flags);
151 list_del(entry: &queue->qlist);
152 spin_unlock_irqrestore(lock: &ptp->tsevqs_lock, flags);
153 bitmap_free(bitmap: queue->mask);
154 kfree(objp: queue);
155 return 0;
156}
157
158long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd,
159 unsigned long arg)
160{
161 struct ptp_clock *ptp =
162 container_of(pccontext->clk, struct ptp_clock, clock);
163 struct ptp_sys_offset_extended *extoff = NULL;
164 struct ptp_sys_offset_precise precise_offset;
165 struct system_device_crosststamp xtstamp;
166 struct ptp_clock_info *ops = ptp->info;
167 struct ptp_sys_offset *sysoff = NULL;
168 struct timestamp_event_queue *tsevq;
169 struct ptp_system_timestamp sts;
170 struct ptp_clock_request req;
171 struct ptp_clock_caps caps;
172 struct ptp_clock_time *pct;
173 unsigned int i, pin_index;
174 struct ptp_pin_desc pd;
175 struct timespec64 ts;
176 int enable, err = 0;
177
178 tsevq = pccontext->private_clkdata;
179
180 switch (cmd) {
181
182 case PTP_CLOCK_GETCAPS:
183 case PTP_CLOCK_GETCAPS2:
184 memset(&caps, 0, sizeof(caps));
185
186 caps.max_adj = ptp->info->max_adj;
187 caps.n_alarm = ptp->info->n_alarm;
188 caps.n_ext_ts = ptp->info->n_ext_ts;
189 caps.n_per_out = ptp->info->n_per_out;
190 caps.pps = ptp->info->pps;
191 caps.n_pins = ptp->info->n_pins;
192 caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
193 caps.adjust_phase = ptp->info->adjphase != NULL &&
194 ptp->info->getmaxphase != NULL;
195 if (caps.adjust_phase)
196 caps.max_phase_adj = ptp->info->getmaxphase(ptp->info);
197 if (copy_to_user(to: (void __user *)arg, from: &caps, n: sizeof(caps)))
198 err = -EFAULT;
199 break;
200
201 case PTP_EXTTS_REQUEST:
202 case PTP_EXTTS_REQUEST2:
203 memset(&req, 0, sizeof(req));
204
205 if (copy_from_user(to: &req.extts, from: (void __user *)arg,
206 n: sizeof(req.extts))) {
207 err = -EFAULT;
208 break;
209 }
210 if (cmd == PTP_EXTTS_REQUEST2) {
211 /* Tell the drivers to check the flags carefully. */
212 req.extts.flags |= PTP_STRICT_FLAGS;
213 /* Make sure no reserved bit is set. */
214 if ((req.extts.flags & ~PTP_EXTTS_VALID_FLAGS) ||
215 req.extts.rsv[0] || req.extts.rsv[1]) {
216 err = -EINVAL;
217 break;
218 }
219 /* Ensure one of the rising/falling edge bits is set. */
220 if ((req.extts.flags & PTP_ENABLE_FEATURE) &&
221 (req.extts.flags & PTP_EXTTS_EDGES) == 0) {
222 err = -EINVAL;
223 break;
224 }
225 } else if (cmd == PTP_EXTTS_REQUEST) {
226 req.extts.flags &= PTP_EXTTS_V1_VALID_FLAGS;
227 req.extts.rsv[0] = 0;
228 req.extts.rsv[1] = 0;
229 }
230 if (req.extts.index >= ops->n_ext_ts) {
231 err = -EINVAL;
232 break;
233 }
234 req.type = PTP_CLK_REQ_EXTTS;
235 enable = req.extts.flags & PTP_ENABLE_FEATURE ? 1 : 0;
236 if (mutex_lock_interruptible(&ptp->pincfg_mux))
237 return -ERESTARTSYS;
238 err = ops->enable(ops, &req, enable);
239 mutex_unlock(lock: &ptp->pincfg_mux);
240 break;
241
242 case PTP_PEROUT_REQUEST:
243 case PTP_PEROUT_REQUEST2:
244 memset(&req, 0, sizeof(req));
245
246 if (copy_from_user(to: &req.perout, from: (void __user *)arg,
247 n: sizeof(req.perout))) {
248 err = -EFAULT;
249 break;
250 }
251 if (cmd == PTP_PEROUT_REQUEST2) {
252 struct ptp_perout_request *perout = &req.perout;
253
254 if (perout->flags & ~PTP_PEROUT_VALID_FLAGS) {
255 err = -EINVAL;
256 break;
257 }
258 /*
259 * The "on" field has undefined meaning if
260 * PTP_PEROUT_DUTY_CYCLE isn't set, we must still treat
261 * it as reserved, which must be set to zero.
262 */
263 if (!(perout->flags & PTP_PEROUT_DUTY_CYCLE) &&
264 (perout->rsv[0] || perout->rsv[1] ||
265 perout->rsv[2] || perout->rsv[3])) {
266 err = -EINVAL;
267 break;
268 }
269 if (perout->flags & PTP_PEROUT_DUTY_CYCLE) {
270 /* The duty cycle must be subunitary. */
271 if (perout->on.sec > perout->period.sec ||
272 (perout->on.sec == perout->period.sec &&
273 perout->on.nsec > perout->period.nsec)) {
274 err = -ERANGE;
275 break;
276 }
277 }
278 if (perout->flags & PTP_PEROUT_PHASE) {
279 /*
280 * The phase should be specified modulo the
281 * period, therefore anything equal or larger
282 * than 1 period is invalid.
283 */
284 if (perout->phase.sec > perout->period.sec ||
285 (perout->phase.sec == perout->period.sec &&
286 perout->phase.nsec >= perout->period.nsec)) {
287 err = -ERANGE;
288 break;
289 }
290 }
291 } else if (cmd == PTP_PEROUT_REQUEST) {
292 req.perout.flags &= PTP_PEROUT_V1_VALID_FLAGS;
293 req.perout.rsv[0] = 0;
294 req.perout.rsv[1] = 0;
295 req.perout.rsv[2] = 0;
296 req.perout.rsv[3] = 0;
297 }
298 if (req.perout.index >= ops->n_per_out) {
299 err = -EINVAL;
300 break;
301 }
302 req.type = PTP_CLK_REQ_PEROUT;
303 enable = req.perout.period.sec || req.perout.period.nsec;
304 if (mutex_lock_interruptible(&ptp->pincfg_mux))
305 return -ERESTARTSYS;
306 err = ops->enable(ops, &req, enable);
307 mutex_unlock(lock: &ptp->pincfg_mux);
308 break;
309
310 case PTP_ENABLE_PPS:
311 case PTP_ENABLE_PPS2:
312 memset(&req, 0, sizeof(req));
313
314 if (!capable(CAP_SYS_TIME))
315 return -EPERM;
316 req.type = PTP_CLK_REQ_PPS;
317 enable = arg ? 1 : 0;
318 if (mutex_lock_interruptible(&ptp->pincfg_mux))
319 return -ERESTARTSYS;
320 err = ops->enable(ops, &req, enable);
321 mutex_unlock(lock: &ptp->pincfg_mux);
322 break;
323
324 case PTP_SYS_OFFSET_PRECISE:
325 case PTP_SYS_OFFSET_PRECISE2:
326 if (!ptp->info->getcrosststamp) {
327 err = -EOPNOTSUPP;
328 break;
329 }
330 err = ptp->info->getcrosststamp(ptp->info, &xtstamp);
331 if (err)
332 break;
333
334 memset(&precise_offset, 0, sizeof(precise_offset));
335 ts = ktime_to_timespec64(xtstamp.device);
336 precise_offset.device.sec = ts.tv_sec;
337 precise_offset.device.nsec = ts.tv_nsec;
338 ts = ktime_to_timespec64(xtstamp.sys_realtime);
339 precise_offset.sys_realtime.sec = ts.tv_sec;
340 precise_offset.sys_realtime.nsec = ts.tv_nsec;
341 ts = ktime_to_timespec64(xtstamp.sys_monoraw);
342 precise_offset.sys_monoraw.sec = ts.tv_sec;
343 precise_offset.sys_monoraw.nsec = ts.tv_nsec;
344 if (copy_to_user(to: (void __user *)arg, from: &precise_offset,
345 n: sizeof(precise_offset)))
346 err = -EFAULT;
347 break;
348
349 case PTP_SYS_OFFSET_EXTENDED:
350 case PTP_SYS_OFFSET_EXTENDED2:
351 if (!ptp->info->gettimex64) {
352 err = -EOPNOTSUPP;
353 break;
354 }
355 extoff = memdup_user((void __user *)arg, sizeof(*extoff));
356 if (IS_ERR(ptr: extoff)) {
357 err = PTR_ERR(ptr: extoff);
358 extoff = NULL;
359 break;
360 }
361 if (extoff->n_samples > PTP_MAX_SAMPLES
362 || extoff->rsv[0] || extoff->rsv[1] || extoff->rsv[2]) {
363 err = -EINVAL;
364 break;
365 }
366 for (i = 0; i < extoff->n_samples; i++) {
367 err = ptp->info->gettimex64(ptp->info, &ts, &sts);
368 if (err)
369 goto out;
370 extoff->ts[i][0].sec = sts.pre_ts.tv_sec;
371 extoff->ts[i][0].nsec = sts.pre_ts.tv_nsec;
372 extoff->ts[i][1].sec = ts.tv_sec;
373 extoff->ts[i][1].nsec = ts.tv_nsec;
374 extoff->ts[i][2].sec = sts.post_ts.tv_sec;
375 extoff->ts[i][2].nsec = sts.post_ts.tv_nsec;
376 }
377 if (copy_to_user(to: (void __user *)arg, from: extoff, n: sizeof(*extoff)))
378 err = -EFAULT;
379 break;
380
381 case PTP_SYS_OFFSET:
382 case PTP_SYS_OFFSET2:
383 sysoff = memdup_user((void __user *)arg, sizeof(*sysoff));
384 if (IS_ERR(ptr: sysoff)) {
385 err = PTR_ERR(ptr: sysoff);
386 sysoff = NULL;
387 break;
388 }
389 if (sysoff->n_samples > PTP_MAX_SAMPLES) {
390 err = -EINVAL;
391 break;
392 }
393 pct = &sysoff->ts[0];
394 for (i = 0; i < sysoff->n_samples; i++) {
395 ktime_get_real_ts64(tv: &ts);
396 pct->sec = ts.tv_sec;
397 pct->nsec = ts.tv_nsec;
398 pct++;
399 if (ops->gettimex64)
400 err = ops->gettimex64(ops, &ts, NULL);
401 else
402 err = ops->gettime64(ops, &ts);
403 if (err)
404 goto out;
405 pct->sec = ts.tv_sec;
406 pct->nsec = ts.tv_nsec;
407 pct++;
408 }
409 ktime_get_real_ts64(tv: &ts);
410 pct->sec = ts.tv_sec;
411 pct->nsec = ts.tv_nsec;
412 if (copy_to_user(to: (void __user *)arg, from: sysoff, n: sizeof(*sysoff)))
413 err = -EFAULT;
414 break;
415
416 case PTP_PIN_GETFUNC:
417 case PTP_PIN_GETFUNC2:
418 if (copy_from_user(to: &pd, from: (void __user *)arg, n: sizeof(pd))) {
419 err = -EFAULT;
420 break;
421 }
422 if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
423 || pd.rsv[3] || pd.rsv[4])
424 && cmd == PTP_PIN_GETFUNC2) {
425 err = -EINVAL;
426 break;
427 } else if (cmd == PTP_PIN_GETFUNC) {
428 pd.rsv[0] = 0;
429 pd.rsv[1] = 0;
430 pd.rsv[2] = 0;
431 pd.rsv[3] = 0;
432 pd.rsv[4] = 0;
433 }
434 pin_index = pd.index;
435 if (pin_index >= ops->n_pins) {
436 err = -EINVAL;
437 break;
438 }
439 pin_index = array_index_nospec(pin_index, ops->n_pins);
440 if (mutex_lock_interruptible(&ptp->pincfg_mux))
441 return -ERESTARTSYS;
442 pd = ops->pin_config[pin_index];
443 mutex_unlock(lock: &ptp->pincfg_mux);
444 if (!err && copy_to_user(to: (void __user *)arg, from: &pd, n: sizeof(pd)))
445 err = -EFAULT;
446 break;
447
448 case PTP_PIN_SETFUNC:
449 case PTP_PIN_SETFUNC2:
450 if (copy_from_user(to: &pd, from: (void __user *)arg, n: sizeof(pd))) {
451 err = -EFAULT;
452 break;
453 }
454 if ((pd.rsv[0] || pd.rsv[1] || pd.rsv[2]
455 || pd.rsv[3] || pd.rsv[4])
456 && cmd == PTP_PIN_SETFUNC2) {
457 err = -EINVAL;
458 break;
459 } else if (cmd == PTP_PIN_SETFUNC) {
460 pd.rsv[0] = 0;
461 pd.rsv[1] = 0;
462 pd.rsv[2] = 0;
463 pd.rsv[3] = 0;
464 pd.rsv[4] = 0;
465 }
466 pin_index = pd.index;
467 if (pin_index >= ops->n_pins) {
468 err = -EINVAL;
469 break;
470 }
471 pin_index = array_index_nospec(pin_index, ops->n_pins);
472 if (mutex_lock_interruptible(&ptp->pincfg_mux))
473 return -ERESTARTSYS;
474 err = ptp_set_pinfunc(ptp, pin: pin_index, func: pd.func, chan: pd.chan);
475 mutex_unlock(lock: &ptp->pincfg_mux);
476 break;
477
478 case PTP_MASK_CLEAR_ALL:
479 bitmap_clear(map: tsevq->mask, start: 0, PTP_MAX_CHANNELS);
480 break;
481
482 case PTP_MASK_EN_SINGLE:
483 if (copy_from_user(to: &i, from: (void __user *)arg, n: sizeof(i))) {
484 err = -EFAULT;
485 break;
486 }
487 if (i >= PTP_MAX_CHANNELS) {
488 err = -EFAULT;
489 break;
490 }
491 set_bit(nr: i, addr: tsevq->mask);
492 break;
493
494 default:
495 err = -ENOTTY;
496 break;
497 }
498
499out:
500 kfree(objp: extoff);
501 kfree(objp: sysoff);
502 return err;
503}
504
505__poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp,
506 poll_table *wait)
507{
508 struct ptp_clock *ptp =
509 container_of(pccontext->clk, struct ptp_clock, clock);
510 struct timestamp_event_queue *queue;
511
512 queue = pccontext->private_clkdata;
513 if (!queue)
514 return EPOLLERR;
515
516 poll_wait(filp: fp, wait_address: &ptp->tsev_wq, p: wait);
517
518 return queue_cnt(q: queue) ? EPOLLIN : 0;
519}
520
521#define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
522
523ssize_t ptp_read(struct posix_clock_context *pccontext, uint rdflags,
524 char __user *buf, size_t cnt)
525{
526 struct ptp_clock *ptp =
527 container_of(pccontext->clk, struct ptp_clock, clock);
528 struct timestamp_event_queue *queue;
529 struct ptp_extts_event *event;
530 unsigned long flags;
531 size_t qcnt, i;
532 int result;
533
534 queue = pccontext->private_clkdata;
535 if (!queue) {
536 result = -EINVAL;
537 goto exit;
538 }
539
540 if (cnt % sizeof(struct ptp_extts_event) != 0) {
541 result = -EINVAL;
542 goto exit;
543 }
544
545 if (cnt > EXTTS_BUFSIZE)
546 cnt = EXTTS_BUFSIZE;
547
548 cnt = cnt / sizeof(struct ptp_extts_event);
549
550 if (wait_event_interruptible(ptp->tsev_wq,
551 ptp->defunct || queue_cnt(queue))) {
552 return -ERESTARTSYS;
553 }
554
555 if (ptp->defunct) {
556 result = -ENODEV;
557 goto exit;
558 }
559
560 event = kmalloc(EXTTS_BUFSIZE, GFP_KERNEL);
561 if (!event) {
562 result = -ENOMEM;
563 goto exit;
564 }
565
566 spin_lock_irqsave(&queue->lock, flags);
567
568 qcnt = queue_cnt(q: queue);
569
570 if (cnt > qcnt)
571 cnt = qcnt;
572
573 for (i = 0; i < cnt; i++) {
574 event[i] = queue->buf[queue->head];
575 /* Paired with READ_ONCE() in queue_cnt() */
576 WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
577 }
578
579 spin_unlock_irqrestore(lock: &queue->lock, flags);
580
581 cnt = cnt * sizeof(struct ptp_extts_event);
582
583 result = cnt;
584 if (copy_to_user(to: buf, from: event, n: cnt)) {
585 result = -EFAULT;
586 goto free_event;
587 }
588
589free_event:
590 kfree(objp: event);
591exit:
592 return result;
593}
594

source code of linux/drivers/ptp/ptp_chardev.c