xref: /linux/drivers/ptp/ptp_sysfs.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
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 sysfs_emit(page, "%d\n", ptp->info->getmaxphase(ptp->info));
28 }
29 static DEVICE_ATTR_RO(max_phase_adjustment);
30 
31 #define PTP_SHOW_INT(name, var)						\
32 static ssize_t var##_show(struct device *dev,				\
33 			   struct device_attribute *attr, char *page)	\
34 {									\
35 	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
36 	return sysfs_emit(page, "%d\n", ptp->info->var);	\
37 }									\
38 static DEVICE_ATTR(name, 0444, var##_show, NULL);
39 
40 PTP_SHOW_INT(max_adjustment, max_adj);
41 PTP_SHOW_INT(n_alarms, n_alarm);
42 PTP_SHOW_INT(n_external_timestamps, n_ext_ts);
43 PTP_SHOW_INT(n_periodic_outputs, n_per_out);
44 PTP_SHOW_INT(n_programmable_pins, n_pins);
45 PTP_SHOW_INT(pps_available, pps);
46 
47 static ssize_t extts_enable_store(struct device *dev,
48 				  struct device_attribute *attr,
49 				  const char *buf, size_t count)
50 {
51 	struct ptp_clock *ptp = dev_get_drvdata(dev);
52 	struct ptp_clock_info *ops = ptp->info;
53 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
54 	int cnt, enable;
55 	int err = -EINVAL;
56 
57 	cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
58 	if (cnt != 2)
59 		goto out;
60 	if (req.extts.index >= ops->n_ext_ts)
61 		goto out;
62 
63 	err = ops->enable(ops, &req, enable ? 1 : 0);
64 	if (err)
65 		goto out;
66 
67 	return count;
68 out:
69 	return err;
70 }
71 static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
72 
73 static ssize_t extts_fifo_show(struct device *dev,
74 			       struct device_attribute *attr, char *page)
75 {
76 	struct ptp_clock *ptp = dev_get_drvdata(dev);
77 	struct timestamp_event_queue *queue;
78 	struct ptp_extts_event event;
79 	unsigned long flags;
80 	size_t qcnt;
81 	int cnt = 0;
82 
83 	cnt = list_count_nodes(&ptp->tsevqs);
84 	if (cnt <= 0)
85 		goto out;
86 
87 	/* The sysfs fifo will always draw from the fist queue */
88 	queue = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue,
89 				 qlist);
90 
91 	memset(&event, 0, sizeof(event));
92 	spin_lock_irqsave(&queue->lock, flags);
93 	qcnt = queue_cnt(queue);
94 	if (qcnt) {
95 		event = queue->buf[queue->head];
96 		/* Paired with READ_ONCE() in queue_cnt() */
97 		WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
98 	}
99 	spin_unlock_irqrestore(&queue->lock, flags);
100 
101 	if (!qcnt)
102 		goto out;
103 
104 	cnt = sysfs_emit(page, "%u %lld %u\n",
105 			 event.index, event.t.sec, event.t.nsec);
106 out:
107 	return cnt;
108 }
109 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
110 
111 static ssize_t period_store(struct device *dev,
112 			    struct device_attribute *attr,
113 			    const char *buf, size_t count)
114 {
115 	struct ptp_clock *ptp = dev_get_drvdata(dev);
116 	struct ptp_clock_info *ops = ptp->info;
117 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
118 	int cnt, enable, err = -EINVAL;
119 
120 	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
121 		     &req.perout.start.sec, &req.perout.start.nsec,
122 		     &req.perout.period.sec, &req.perout.period.nsec);
123 	if (cnt != 5)
124 		goto out;
125 	if (req.perout.index >= ops->n_per_out)
126 		goto out;
127 
128 	enable = req.perout.period.sec || req.perout.period.nsec;
129 	err = ops->enable(ops, &req, enable);
130 	if (err)
131 		goto out;
132 
133 	return count;
134 out:
135 	return err;
136 }
137 static DEVICE_ATTR(period, 0220, NULL, period_store);
138 
139 static ssize_t pps_enable_store(struct device *dev,
140 				struct device_attribute *attr,
141 				const char *buf, size_t count)
142 {
143 	struct ptp_clock *ptp = dev_get_drvdata(dev);
144 	struct ptp_clock_info *ops = ptp->info;
145 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
146 	int cnt, enable;
147 	int err = -EINVAL;
148 
149 	if (!capable(CAP_SYS_TIME))
150 		return -EPERM;
151 
152 	cnt = sscanf(buf, "%d", &enable);
153 	if (cnt != 1)
154 		goto out;
155 
156 	err = ops->enable(ops, &req, enable ? 1 : 0);
157 	if (err)
158 		goto out;
159 
160 	return count;
161 out:
162 	return err;
163 }
164 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
165 
166 static int unregister_vclock(struct device *dev, void *data)
167 {
168 	struct ptp_clock *ptp = dev_get_drvdata(dev);
169 	struct ptp_clock_info *info = ptp->info;
170 	struct ptp_vclock *vclock;
171 	u32 *num = data;
172 
173 	vclock = info_to_vclock(info);
174 	dev_info(dev->parent, "delete virtual clock ptp%d\n",
175 		 vclock->clock->index);
176 
177 	ptp_vclock_unregister(vclock);
178 	(*num)--;
179 
180 	/* For break. Not error. */
181 	if (*num == 0)
182 		return -EINVAL;
183 
184 	return 0;
185 }
186 
187 static ssize_t n_vclocks_show(struct device *dev,
188 			      struct device_attribute *attr, char *page)
189 {
190 	struct ptp_clock *ptp = dev_get_drvdata(dev);
191 	ssize_t size;
192 
193 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
194 		return -ERESTARTSYS;
195 
196 	size = sysfs_emit(page, "%u\n", ptp->n_vclocks);
197 
198 	mutex_unlock(&ptp->n_vclocks_mux);
199 
200 	return size;
201 }
202 
203 static ssize_t n_vclocks_store(struct device *dev,
204 			       struct device_attribute *attr,
205 			       const char *buf, size_t count)
206 {
207 	struct ptp_clock *ptp = dev_get_drvdata(dev);
208 	struct ptp_vclock *vclock;
209 	int err = -EINVAL;
210 	u32 num, i;
211 
212 	if (kstrtou32(buf, 0, &num))
213 		return err;
214 
215 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
216 		return -ERESTARTSYS;
217 
218 	if (num > ptp->max_vclocks) {
219 		dev_err(dev, "max value is %d\n", ptp->max_vclocks);
220 		goto out;
221 	}
222 
223 	/* Need to create more vclocks */
224 	if (num > ptp->n_vclocks) {
225 		for (i = 0; i < num - ptp->n_vclocks; i++) {
226 			vclock = ptp_vclock_register(ptp);
227 			if (!vclock)
228 				goto out;
229 
230 			*(ptp->vclock_index + ptp->n_vclocks + i) =
231 				vclock->clock->index;
232 
233 			dev_info(dev, "new virtual clock ptp%d\n",
234 				 vclock->clock->index);
235 		}
236 	}
237 
238 	/* Need to delete vclocks */
239 	if (num < ptp->n_vclocks) {
240 		i = ptp->n_vclocks - num;
241 		device_for_each_child_reverse(dev, &i,
242 					      unregister_vclock);
243 
244 		for (i = 1; i <= ptp->n_vclocks - num; i++)
245 			*(ptp->vclock_index + ptp->n_vclocks - i) = -1;
246 	}
247 
248 	/* Need to inform about changed physical clock behavior */
249 	if (!ptp->has_cycles) {
250 		if (num == 0)
251 			dev_info(dev, "only physical clock in use now\n");
252 		else
253 			dev_info(dev, "guarantee physical clock free running\n");
254 	}
255 
256 	ptp->n_vclocks = num;
257 	mutex_unlock(&ptp->n_vclocks_mux);
258 
259 	return count;
260 out:
261 	mutex_unlock(&ptp->n_vclocks_mux);
262 	return err;
263 }
264 static DEVICE_ATTR_RW(n_vclocks);
265 
266 static ssize_t max_vclocks_show(struct device *dev,
267 				struct device_attribute *attr, char *page)
268 {
269 	struct ptp_clock *ptp = dev_get_drvdata(dev);
270 	ssize_t size;
271 
272 	size = sysfs_emit(page, "%u\n", ptp->max_vclocks);
273 
274 	return size;
275 }
276 
277 static ssize_t max_vclocks_store(struct device *dev,
278 				 struct device_attribute *attr,
279 				 const char *buf, size_t count)
280 {
281 	struct ptp_clock *ptp = dev_get_drvdata(dev);
282 	unsigned int *vclock_index;
283 	int err = -EINVAL;
284 	size_t size;
285 	u32 max;
286 
287 	if (kstrtou32(buf, 0, &max) || max == 0)
288 		return -EINVAL;
289 
290 	if (max == ptp->max_vclocks)
291 		return count;
292 
293 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
294 		return -ERESTARTSYS;
295 
296 	if (max < ptp->n_vclocks)
297 		goto out;
298 
299 	size = sizeof(int) * max;
300 	vclock_index = kzalloc(size, GFP_KERNEL);
301 	if (!vclock_index) {
302 		err = -ENOMEM;
303 		goto out;
304 	}
305 
306 	size = sizeof(int) * ptp->n_vclocks;
307 	memcpy(vclock_index, ptp->vclock_index, size);
308 
309 	kfree(ptp->vclock_index);
310 	ptp->vclock_index = vclock_index;
311 	ptp->max_vclocks = max;
312 
313 	mutex_unlock(&ptp->n_vclocks_mux);
314 
315 	return count;
316 out:
317 	mutex_unlock(&ptp->n_vclocks_mux);
318 	return err;
319 }
320 static DEVICE_ATTR_RW(max_vclocks);
321 
322 static struct attribute *ptp_attrs[] = {
323 	&dev_attr_clock_name.attr,
324 
325 	&dev_attr_max_adjustment.attr,
326 	&dev_attr_max_phase_adjustment.attr,
327 	&dev_attr_n_alarms.attr,
328 	&dev_attr_n_external_timestamps.attr,
329 	&dev_attr_n_periodic_outputs.attr,
330 	&dev_attr_n_programmable_pins.attr,
331 	&dev_attr_pps_available.attr,
332 
333 	&dev_attr_extts_enable.attr,
334 	&dev_attr_fifo.attr,
335 	&dev_attr_period.attr,
336 	&dev_attr_pps_enable.attr,
337 	&dev_attr_n_vclocks.attr,
338 	&dev_attr_max_vclocks.attr,
339 	NULL
340 };
341 
342 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
343 					struct attribute *attr, int n)
344 {
345 	struct device *dev = kobj_to_dev(kobj);
346 	struct ptp_clock *ptp = dev_get_drvdata(dev);
347 	struct ptp_clock_info *info = ptp->info;
348 	umode_t mode = attr->mode;
349 
350 	if (attr == &dev_attr_extts_enable.attr ||
351 	    attr == &dev_attr_fifo.attr) {
352 		if (!info->n_ext_ts)
353 			mode = 0;
354 	} else if (attr == &dev_attr_period.attr) {
355 		if (!info->n_per_out)
356 			mode = 0;
357 	} else if (attr == &dev_attr_pps_enable.attr) {
358 		if (!info->pps)
359 			mode = 0;
360 	} else if (attr == &dev_attr_n_vclocks.attr ||
361 		   attr == &dev_attr_max_vclocks.attr) {
362 		if (ptp->is_virtual_clock)
363 			mode = 0;
364 	} else if (attr == &dev_attr_max_phase_adjustment.attr) {
365 		if (!info->adjphase || !info->getmaxphase)
366 			mode = 0;
367 	}
368 
369 	return mode;
370 }
371 
372 static const struct attribute_group ptp_group = {
373 	.is_visible	= ptp_is_attribute_visible,
374 	.attrs		= ptp_attrs,
375 };
376 
377 const struct attribute_group *ptp_groups[] = {
378 	&ptp_group,
379 	NULL
380 };
381 
382 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
383 {
384 	int i;
385 	for (i = 0; i < ptp->info->n_pins; i++) {
386 		if (!strcmp(ptp->info->pin_config[i].name, name))
387 			return i;
388 	}
389 	return -1;
390 }
391 
392 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
393 			    char *page)
394 {
395 	struct ptp_clock *ptp = dev_get_drvdata(dev);
396 	unsigned int func, chan;
397 	int index;
398 
399 	index = ptp_pin_name2index(ptp, attr->attr.name);
400 	if (index < 0)
401 		return -EINVAL;
402 
403 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
404 		return -ERESTARTSYS;
405 
406 	func = ptp->info->pin_config[index].func;
407 	chan = ptp->info->pin_config[index].chan;
408 
409 	mutex_unlock(&ptp->pincfg_mux);
410 
411 	return sysfs_emit(page, "%u %u\n", func, chan);
412 }
413 
414 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
415 			     const char *buf, size_t count)
416 {
417 	struct ptp_clock *ptp = dev_get_drvdata(dev);
418 	unsigned int func, chan;
419 	int cnt, err, index;
420 
421 	cnt = sscanf(buf, "%u %u", &func, &chan);
422 	if (cnt != 2)
423 		return -EINVAL;
424 
425 	index = ptp_pin_name2index(ptp, attr->attr.name);
426 	if (index < 0)
427 		return -EINVAL;
428 
429 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
430 		return -ERESTARTSYS;
431 	err = ptp_set_pinfunc(ptp, index, func, chan);
432 	mutex_unlock(&ptp->pincfg_mux);
433 	if (err)
434 		return err;
435 
436 	return count;
437 }
438 
439 int ptp_populate_pin_groups(struct ptp_clock *ptp)
440 {
441 	struct ptp_clock_info *info = ptp->info;
442 	int err = -ENOMEM, i, n_pins = info->n_pins;
443 
444 	if (!n_pins)
445 		return 0;
446 
447 	ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
448 				    GFP_KERNEL);
449 	if (!ptp->pin_dev_attr)
450 		goto no_dev_attr;
451 
452 	ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
453 	if (!ptp->pin_attr)
454 		goto no_pin_attr;
455 
456 	for (i = 0; i < n_pins; i++) {
457 		struct device_attribute *da = &ptp->pin_dev_attr[i];
458 		sysfs_attr_init(&da->attr);
459 		da->attr.name = info->pin_config[i].name;
460 		da->attr.mode = 0644;
461 		da->show = ptp_pin_show;
462 		da->store = ptp_pin_store;
463 		ptp->pin_attr[i] = &da->attr;
464 	}
465 
466 	ptp->pin_attr_group.name = "pins";
467 	ptp->pin_attr_group.attrs = ptp->pin_attr;
468 
469 	ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
470 
471 	return 0;
472 
473 no_pin_attr:
474 	kfree(ptp->pin_dev_attr);
475 no_dev_attr:
476 	return err;
477 }
478 
479 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
480 {
481 	kfree(ptp->pin_attr);
482 	kfree(ptp->pin_dev_attr);
483 }
484