xref: /linux/drivers/ptp/ptp_sysfs.c (revision b17ef04bf3a4346d66404454d6a646343ddc9749)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * PTP 1588 clock support - sysfs interface.
4  *
5  * Copyright (C) 2010 OMICRON electronics GmbH
6  * Copyright 2021 NXP
7  */
8 #include <linux/capability.h>
9 #include <linux/slab.h>
10 
11 #include "ptp_private.h"
12 
13 static ssize_t clock_name_show(struct device *dev,
14 			       struct device_attribute *attr, char *page)
15 {
16 	struct ptp_clock *ptp = dev_get_drvdata(dev);
17 	return sysfs_emit(page, "%s\n", ptp->info->name);
18 }
19 static DEVICE_ATTR_RO(clock_name);
20 
21 static ssize_t max_phase_adjustment_show(struct device *dev,
22 					 struct device_attribute *attr,
23 					 char *page)
24 {
25 	struct ptp_clock *ptp = dev_get_drvdata(dev);
26 
27 	return snprintf(page, PAGE_SIZE - 1, "%d\n",
28 			ptp->info->getmaxphase(ptp->info));
29 }
30 static DEVICE_ATTR_RO(max_phase_adjustment);
31 
32 #define PTP_SHOW_INT(name, var)						\
33 static ssize_t var##_show(struct device *dev,				\
34 			   struct device_attribute *attr, char *page)	\
35 {									\
36 	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
37 	return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->var);	\
38 }									\
39 static DEVICE_ATTR(name, 0444, var##_show, NULL);
40 
41 PTP_SHOW_INT(max_adjustment, max_adj);
42 PTP_SHOW_INT(n_alarms, n_alarm);
43 PTP_SHOW_INT(n_external_timestamps, n_ext_ts);
44 PTP_SHOW_INT(n_periodic_outputs, n_per_out);
45 PTP_SHOW_INT(n_programmable_pins, n_pins);
46 PTP_SHOW_INT(pps_available, pps);
47 
48 static ssize_t extts_enable_store(struct device *dev,
49 				  struct device_attribute *attr,
50 				  const char *buf, size_t count)
51 {
52 	struct ptp_clock *ptp = dev_get_drvdata(dev);
53 	struct ptp_clock_info *ops = ptp->info;
54 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
55 	int cnt, enable;
56 	int err = -EINVAL;
57 
58 	cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
59 	if (cnt != 2)
60 		goto out;
61 	if (req.extts.index >= ops->n_ext_ts)
62 		goto out;
63 
64 	err = ops->enable(ops, &req, enable ? 1 : 0);
65 	if (err)
66 		goto out;
67 
68 	return count;
69 out:
70 	return err;
71 }
72 static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
73 
74 static ssize_t extts_fifo_show(struct device *dev,
75 			       struct device_attribute *attr, char *page)
76 {
77 	struct ptp_clock *ptp = dev_get_drvdata(dev);
78 	struct timestamp_event_queue *queue;
79 	struct ptp_extts_event event;
80 	unsigned long flags;
81 	size_t qcnt;
82 	int cnt = 0;
83 
84 	cnt = list_count_nodes(&ptp->tsevqs);
85 	if (cnt <= 0)
86 		goto out;
87 
88 	/* The sysfs fifo will always draw from the fist queue */
89 	queue = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue,
90 				 qlist);
91 
92 	memset(&event, 0, sizeof(event));
93 	spin_lock_irqsave(&queue->lock, flags);
94 	qcnt = queue_cnt(queue);
95 	if (qcnt) {
96 		event = queue->buf[queue->head];
97 		/* Paired with READ_ONCE() in queue_cnt() */
98 		WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
99 	}
100 	spin_unlock_irqrestore(&queue->lock, flags);
101 
102 	if (!qcnt)
103 		goto out;
104 
105 	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
106 		       event.index, event.t.sec, event.t.nsec);
107 out:
108 	return cnt;
109 }
110 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
111 
112 static ssize_t period_store(struct device *dev,
113 			    struct device_attribute *attr,
114 			    const char *buf, size_t count)
115 {
116 	struct ptp_clock *ptp = dev_get_drvdata(dev);
117 	struct ptp_clock_info *ops = ptp->info;
118 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
119 	int cnt, enable, err = -EINVAL;
120 
121 	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
122 		     &req.perout.start.sec, &req.perout.start.nsec,
123 		     &req.perout.period.sec, &req.perout.period.nsec);
124 	if (cnt != 5)
125 		goto out;
126 	if (req.perout.index >= ops->n_per_out)
127 		goto out;
128 
129 	enable = req.perout.period.sec || req.perout.period.nsec;
130 	err = ops->enable(ops, &req, enable);
131 	if (err)
132 		goto out;
133 
134 	return count;
135 out:
136 	return err;
137 }
138 static DEVICE_ATTR(period, 0220, NULL, period_store);
139 
140 static ssize_t pps_enable_store(struct device *dev,
141 				struct device_attribute *attr,
142 				const char *buf, size_t count)
143 {
144 	struct ptp_clock *ptp = dev_get_drvdata(dev);
145 	struct ptp_clock_info *ops = ptp->info;
146 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
147 	int cnt, enable;
148 	int err = -EINVAL;
149 
150 	if (!capable(CAP_SYS_TIME))
151 		return -EPERM;
152 
153 	cnt = sscanf(buf, "%d", &enable);
154 	if (cnt != 1)
155 		goto out;
156 
157 	err = ops->enable(ops, &req, enable ? 1 : 0);
158 	if (err)
159 		goto out;
160 
161 	return count;
162 out:
163 	return err;
164 }
165 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
166 
167 static int unregister_vclock(struct device *dev, void *data)
168 {
169 	struct ptp_clock *ptp = dev_get_drvdata(dev);
170 	struct ptp_clock_info *info = ptp->info;
171 	struct ptp_vclock *vclock;
172 	u32 *num = data;
173 
174 	vclock = info_to_vclock(info);
175 	dev_info(dev->parent, "delete virtual clock ptp%d\n",
176 		 vclock->clock->index);
177 
178 	ptp_vclock_unregister(vclock);
179 	(*num)--;
180 
181 	/* For break. Not error. */
182 	if (*num == 0)
183 		return -EINVAL;
184 
185 	return 0;
186 }
187 
188 static ssize_t n_vclocks_show(struct device *dev,
189 			      struct device_attribute *attr, char *page)
190 {
191 	struct ptp_clock *ptp = dev_get_drvdata(dev);
192 	ssize_t size;
193 
194 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
195 		return -ERESTARTSYS;
196 
197 	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);
198 
199 	mutex_unlock(&ptp->n_vclocks_mux);
200 
201 	return size;
202 }
203 
204 static ssize_t n_vclocks_store(struct device *dev,
205 			       struct device_attribute *attr,
206 			       const char *buf, size_t count)
207 {
208 	struct ptp_clock *ptp = dev_get_drvdata(dev);
209 	struct ptp_vclock *vclock;
210 	int err = -EINVAL;
211 	u32 num, i;
212 
213 	if (kstrtou32(buf, 0, &num))
214 		return err;
215 
216 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
217 		return -ERESTARTSYS;
218 
219 	if (num > ptp->max_vclocks) {
220 		dev_err(dev, "max value is %d\n", ptp->max_vclocks);
221 		goto out;
222 	}
223 
224 	/* Need to create more vclocks */
225 	if (num > ptp->n_vclocks) {
226 		for (i = 0; i < num - ptp->n_vclocks; i++) {
227 			vclock = ptp_vclock_register(ptp);
228 			if (!vclock)
229 				goto out;
230 
231 			*(ptp->vclock_index + ptp->n_vclocks + i) =
232 				vclock->clock->index;
233 
234 			dev_info(dev, "new virtual clock ptp%d\n",
235 				 vclock->clock->index);
236 		}
237 	}
238 
239 	/* Need to delete vclocks */
240 	if (num < ptp->n_vclocks) {
241 		i = ptp->n_vclocks - num;
242 		device_for_each_child_reverse(dev, &i,
243 					      unregister_vclock);
244 
245 		for (i = 1; i <= ptp->n_vclocks - num; i++)
246 			*(ptp->vclock_index + ptp->n_vclocks - i) = -1;
247 	}
248 
249 	/* Need to inform about changed physical clock behavior */
250 	if (!ptp->has_cycles) {
251 		if (num == 0)
252 			dev_info(dev, "only physical clock in use now\n");
253 		else
254 			dev_info(dev, "guarantee physical clock free running\n");
255 	}
256 
257 	ptp->n_vclocks = num;
258 	mutex_unlock(&ptp->n_vclocks_mux);
259 
260 	return count;
261 out:
262 	mutex_unlock(&ptp->n_vclocks_mux);
263 	return err;
264 }
265 static DEVICE_ATTR_RW(n_vclocks);
266 
267 static ssize_t max_vclocks_show(struct device *dev,
268 				struct device_attribute *attr, char *page)
269 {
270 	struct ptp_clock *ptp = dev_get_drvdata(dev);
271 	ssize_t size;
272 
273 	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);
274 
275 	return size;
276 }
277 
278 static ssize_t max_vclocks_store(struct device *dev,
279 				 struct device_attribute *attr,
280 				 const char *buf, size_t count)
281 {
282 	struct ptp_clock *ptp = dev_get_drvdata(dev);
283 	unsigned int *vclock_index;
284 	int err = -EINVAL;
285 	size_t size;
286 	u32 max;
287 
288 	if (kstrtou32(buf, 0, &max) || max == 0)
289 		return -EINVAL;
290 
291 	if (max == ptp->max_vclocks)
292 		return count;
293 
294 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
295 		return -ERESTARTSYS;
296 
297 	if (max < ptp->n_vclocks)
298 		goto out;
299 
300 	size = sizeof(int) * max;
301 	vclock_index = kzalloc(size, GFP_KERNEL);
302 	if (!vclock_index) {
303 		err = -ENOMEM;
304 		goto out;
305 	}
306 
307 	size = sizeof(int) * ptp->n_vclocks;
308 	memcpy(vclock_index, ptp->vclock_index, size);
309 
310 	kfree(ptp->vclock_index);
311 	ptp->vclock_index = vclock_index;
312 	ptp->max_vclocks = max;
313 
314 	mutex_unlock(&ptp->n_vclocks_mux);
315 
316 	return count;
317 out:
318 	mutex_unlock(&ptp->n_vclocks_mux);
319 	return err;
320 }
321 static DEVICE_ATTR_RW(max_vclocks);
322 
323 static struct attribute *ptp_attrs[] = {
324 	&dev_attr_clock_name.attr,
325 
326 	&dev_attr_max_adjustment.attr,
327 	&dev_attr_max_phase_adjustment.attr,
328 	&dev_attr_n_alarms.attr,
329 	&dev_attr_n_external_timestamps.attr,
330 	&dev_attr_n_periodic_outputs.attr,
331 	&dev_attr_n_programmable_pins.attr,
332 	&dev_attr_pps_available.attr,
333 
334 	&dev_attr_extts_enable.attr,
335 	&dev_attr_fifo.attr,
336 	&dev_attr_period.attr,
337 	&dev_attr_pps_enable.attr,
338 	&dev_attr_n_vclocks.attr,
339 	&dev_attr_max_vclocks.attr,
340 	NULL
341 };
342 
343 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
344 					struct attribute *attr, int n)
345 {
346 	struct device *dev = kobj_to_dev(kobj);
347 	struct ptp_clock *ptp = dev_get_drvdata(dev);
348 	struct ptp_clock_info *info = ptp->info;
349 	umode_t mode = attr->mode;
350 
351 	if (attr == &dev_attr_extts_enable.attr ||
352 	    attr == &dev_attr_fifo.attr) {
353 		if (!info->n_ext_ts)
354 			mode = 0;
355 	} else if (attr == &dev_attr_period.attr) {
356 		if (!info->n_per_out)
357 			mode = 0;
358 	} else if (attr == &dev_attr_pps_enable.attr) {
359 		if (!info->pps)
360 			mode = 0;
361 	} else if (attr == &dev_attr_n_vclocks.attr ||
362 		   attr == &dev_attr_max_vclocks.attr) {
363 		if (ptp->is_virtual_clock)
364 			mode = 0;
365 	} else if (attr == &dev_attr_max_phase_adjustment.attr) {
366 		if (!info->adjphase || !info->getmaxphase)
367 			mode = 0;
368 	}
369 
370 	return mode;
371 }
372 
373 static const struct attribute_group ptp_group = {
374 	.is_visible	= ptp_is_attribute_visible,
375 	.attrs		= ptp_attrs,
376 };
377 
378 const struct attribute_group *ptp_groups[] = {
379 	&ptp_group,
380 	NULL
381 };
382 
383 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
384 {
385 	int i;
386 	for (i = 0; i < ptp->info->n_pins; i++) {
387 		if (!strcmp(ptp->info->pin_config[i].name, name))
388 			return i;
389 	}
390 	return -1;
391 }
392 
393 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
394 			    char *page)
395 {
396 	struct ptp_clock *ptp = dev_get_drvdata(dev);
397 	unsigned int func, chan;
398 	int index;
399 
400 	index = ptp_pin_name2index(ptp, attr->attr.name);
401 	if (index < 0)
402 		return -EINVAL;
403 
404 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
405 		return -ERESTARTSYS;
406 
407 	func = ptp->info->pin_config[index].func;
408 	chan = ptp->info->pin_config[index].chan;
409 
410 	mutex_unlock(&ptp->pincfg_mux);
411 
412 	return sysfs_emit(page, "%u %u\n", func, chan);
413 }
414 
415 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
416 			     const char *buf, size_t count)
417 {
418 	struct ptp_clock *ptp = dev_get_drvdata(dev);
419 	unsigned int func, chan;
420 	int cnt, err, index;
421 
422 	cnt = sscanf(buf, "%u %u", &func, &chan);
423 	if (cnt != 2)
424 		return -EINVAL;
425 
426 	index = ptp_pin_name2index(ptp, attr->attr.name);
427 	if (index < 0)
428 		return -EINVAL;
429 
430 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
431 		return -ERESTARTSYS;
432 	err = ptp_set_pinfunc(ptp, index, func, chan);
433 	mutex_unlock(&ptp->pincfg_mux);
434 	if (err)
435 		return err;
436 
437 	return count;
438 }
439 
440 int ptp_populate_pin_groups(struct ptp_clock *ptp)
441 {
442 	struct ptp_clock_info *info = ptp->info;
443 	int err = -ENOMEM, i, n_pins = info->n_pins;
444 
445 	if (!n_pins)
446 		return 0;
447 
448 	ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
449 				    GFP_KERNEL);
450 	if (!ptp->pin_dev_attr)
451 		goto no_dev_attr;
452 
453 	ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
454 	if (!ptp->pin_attr)
455 		goto no_pin_attr;
456 
457 	for (i = 0; i < n_pins; i++) {
458 		struct device_attribute *da = &ptp->pin_dev_attr[i];
459 		sysfs_attr_init(&da->attr);
460 		da->attr.name = info->pin_config[i].name;
461 		da->attr.mode = 0644;
462 		da->show = ptp_pin_show;
463 		da->store = ptp_pin_store;
464 		ptp->pin_attr[i] = &da->attr;
465 	}
466 
467 	ptp->pin_attr_group.name = "pins";
468 	ptp->pin_attr_group.attrs = ptp->pin_attr;
469 
470 	ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
471 
472 	return 0;
473 
474 no_pin_attr:
475 	kfree(ptp->pin_dev_attr);
476 no_dev_attr:
477 	return err;
478 }
479 
480 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
481 {
482 	kfree(ptp->pin_attr);
483 	kfree(ptp->pin_dev_attr);
484 }
485