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(info, func, chan);
95		pin1->func = PTP_PF_NONE;
96		pin1->chan = 0;
97	}
98	ptp_disable_pinfunc(info, pin2->func, 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(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(queue);
119		return -EINVAL;
120	}
121	bitmap_set(queue->mask, 0, PTP_MAX_CHANNELS);
122	spin_lock_init(&queue->lock);
123	spin_lock_irqsave(&ptp->tsevqs_lock, flags);
124	list_add_tail(&queue->qlist, &ptp->tsevqs);
125	spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);
126	pccontext->private_clkdata = queue;
127
128	/* Debugfs contents */
129	sprintf(debugfsname, "0x%p", queue);
130	queue->debugfs_instance =
131		debugfs_create_dir(debugfsname, 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("mask", 0444, queue->debugfs_instance,
136				 &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(queue->debugfs_instance);
149	pccontext->private_clkdata = NULL;
150	spin_lock_irqsave(&ptp->tsevqs_lock, flags);
151	list_del(&queue->qlist);
152	spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);
153	bitmap_free(queue->mask);
154	kfree(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((void __user *)arg, &caps, 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(&req.extts, (void __user *)arg,
206				   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(&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(&req.perout, (void __user *)arg,
247				   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(&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(&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((void __user *)arg, &precise_offset,
345				 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(extoff)) {
357			err = PTR_ERR(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((void __user *)arg, extoff, 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(sysoff)) {
385			err = PTR_ERR(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(&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(&ts);
410		pct->sec = ts.tv_sec;
411		pct->nsec = ts.tv_nsec;
412		if (copy_to_user((void __user *)arg, sysoff, sizeof(*sysoff)))
413			err = -EFAULT;
414		break;
415
416	case PTP_PIN_GETFUNC:
417	case PTP_PIN_GETFUNC2:
418		if (copy_from_user(&pd, (void __user *)arg, 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(&ptp->pincfg_mux);
444		if (!err && copy_to_user((void __user *)arg, &pd, sizeof(pd)))
445			err = -EFAULT;
446		break;
447
448	case PTP_PIN_SETFUNC:
449	case PTP_PIN_SETFUNC2:
450		if (copy_from_user(&pd, (void __user *)arg, 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_index, pd.func, pd.chan);
475		mutex_unlock(&ptp->pincfg_mux);
476		break;
477
478	case PTP_MASK_CLEAR_ALL:
479		bitmap_clear(tsevq->mask, 0, PTP_MAX_CHANNELS);
480		break;
481
482	case PTP_MASK_EN_SINGLE:
483		if (copy_from_user(&i, (void __user *)arg, sizeof(i))) {
484			err = -EFAULT;
485			break;
486		}
487		if (i >= PTP_MAX_CHANNELS) {
488			err = -EFAULT;
489			break;
490		}
491		set_bit(i, tsevq->mask);
492		break;
493
494	default:
495		err = -ENOTTY;
496		break;
497	}
498
499out:
500	kfree(extoff);
501	kfree(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(fp, &ptp->tsev_wq, wait);
517
518	return queue_cnt(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(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(&queue->lock, flags);
580
581	cnt = cnt * sizeof(struct ptp_extts_event);
582
583	result = cnt;
584	if (copy_to_user(buf, event, cnt)) {
585		result = -EFAULT;
586		goto free_event;
587	}
588
589free_event:
590	kfree(event);
591exit:
592	return result;
593}
594