xref: /openbmc/linux/drivers/ptp/ptp_sysfs.c (revision 94b00cd6)
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 = &ptp->tsevq;
79 	struct ptp_extts_event event;
80 	unsigned long flags;
81 	size_t qcnt;
82 	int cnt = 0;
83 
84 	memset(&event, 0, sizeof(event));
85 
86 	if (mutex_lock_interruptible(&ptp->tsevq_mux))
87 		return -ERESTARTSYS;
88 
89 	spin_lock_irqsave(&queue->lock, flags);
90 	qcnt = queue_cnt(queue);
91 	if (qcnt) {
92 		event = queue->buf[queue->head];
93 		/* Paired with READ_ONCE() in queue_cnt() */
94 		WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);
95 	}
96 	spin_unlock_irqrestore(&queue->lock, flags);
97 
98 	if (!qcnt)
99 		goto out;
100 
101 	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
102 		       event.index, event.t.sec, event.t.nsec);
103 out:
104 	mutex_unlock(&ptp->tsevq_mux);
105 	return cnt;
106 }
107 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
108 
109 static ssize_t period_store(struct device *dev,
110 			    struct device_attribute *attr,
111 			    const char *buf, size_t count)
112 {
113 	struct ptp_clock *ptp = dev_get_drvdata(dev);
114 	struct ptp_clock_info *ops = ptp->info;
115 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
116 	int cnt, enable, err = -EINVAL;
117 
118 	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
119 		     &req.perout.start.sec, &req.perout.start.nsec,
120 		     &req.perout.period.sec, &req.perout.period.nsec);
121 	if (cnt != 5)
122 		goto out;
123 	if (req.perout.index >= ops->n_per_out)
124 		goto out;
125 
126 	enable = req.perout.period.sec || req.perout.period.nsec;
127 	err = ops->enable(ops, &req, enable);
128 	if (err)
129 		goto out;
130 
131 	return count;
132 out:
133 	return err;
134 }
135 static DEVICE_ATTR(period, 0220, NULL, period_store);
136 
137 static ssize_t pps_enable_store(struct device *dev,
138 				struct device_attribute *attr,
139 				const char *buf, size_t count)
140 {
141 	struct ptp_clock *ptp = dev_get_drvdata(dev);
142 	struct ptp_clock_info *ops = ptp->info;
143 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
144 	int cnt, enable;
145 	int err = -EINVAL;
146 
147 	if (!capable(CAP_SYS_TIME))
148 		return -EPERM;
149 
150 	cnt = sscanf(buf, "%d", &enable);
151 	if (cnt != 1)
152 		goto out;
153 
154 	err = ops->enable(ops, &req, enable ? 1 : 0);
155 	if (err)
156 		goto out;
157 
158 	return count;
159 out:
160 	return err;
161 }
162 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
163 
164 static int unregister_vclock(struct device *dev, void *data)
165 {
166 	struct ptp_clock *ptp = dev_get_drvdata(dev);
167 	struct ptp_clock_info *info = ptp->info;
168 	struct ptp_vclock *vclock;
169 	u32 *num = data;
170 
171 	vclock = info_to_vclock(info);
172 	dev_info(dev->parent, "delete virtual clock ptp%d\n",
173 		 vclock->clock->index);
174 
175 	ptp_vclock_unregister(vclock);
176 	(*num)--;
177 
178 	/* For break. Not error. */
179 	if (*num == 0)
180 		return -EINVAL;
181 
182 	return 0;
183 }
184 
185 static ssize_t n_vclocks_show(struct device *dev,
186 			      struct device_attribute *attr, char *page)
187 {
188 	struct ptp_clock *ptp = dev_get_drvdata(dev);
189 	ssize_t size;
190 
191 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
192 		return -ERESTARTSYS;
193 
194 	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);
195 
196 	mutex_unlock(&ptp->n_vclocks_mux);
197 
198 	return size;
199 }
200 
201 static ssize_t n_vclocks_store(struct device *dev,
202 			       struct device_attribute *attr,
203 			       const char *buf, size_t count)
204 {
205 	struct ptp_clock *ptp = dev_get_drvdata(dev);
206 	struct ptp_vclock *vclock;
207 	int err = -EINVAL;
208 	u32 num, i;
209 
210 	if (kstrtou32(buf, 0, &num))
211 		return err;
212 
213 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
214 		return -ERESTARTSYS;
215 
216 	if (num > ptp->max_vclocks) {
217 		dev_err(dev, "max value is %d\n", ptp->max_vclocks);
218 		goto out;
219 	}
220 
221 	/* Need to create more vclocks */
222 	if (num > ptp->n_vclocks) {
223 		for (i = 0; i < num - ptp->n_vclocks; i++) {
224 			vclock = ptp_vclock_register(ptp);
225 			if (!vclock)
226 				goto out;
227 
228 			*(ptp->vclock_index + ptp->n_vclocks + i) =
229 				vclock->clock->index;
230 
231 			dev_info(dev, "new virtual clock ptp%d\n",
232 				 vclock->clock->index);
233 		}
234 	}
235 
236 	/* Need to delete vclocks */
237 	if (num < ptp->n_vclocks) {
238 		i = ptp->n_vclocks - num;
239 		device_for_each_child_reverse(dev, &i,
240 					      unregister_vclock);
241 
242 		for (i = 1; i <= ptp->n_vclocks - num; i++)
243 			*(ptp->vclock_index + ptp->n_vclocks - i) = -1;
244 	}
245 
246 	/* Need to inform about changed physical clock behavior */
247 	if (!ptp->has_cycles) {
248 		if (num == 0)
249 			dev_info(dev, "only physical clock in use now\n");
250 		else
251 			dev_info(dev, "guarantee physical clock free running\n");
252 	}
253 
254 	ptp->n_vclocks = num;
255 	mutex_unlock(&ptp->n_vclocks_mux);
256 
257 	return count;
258 out:
259 	mutex_unlock(&ptp->n_vclocks_mux);
260 	return err;
261 }
262 static DEVICE_ATTR_RW(n_vclocks);
263 
264 static ssize_t max_vclocks_show(struct device *dev,
265 				struct device_attribute *attr, char *page)
266 {
267 	struct ptp_clock *ptp = dev_get_drvdata(dev);
268 	ssize_t size;
269 
270 	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);
271 
272 	return size;
273 }
274 
275 static ssize_t max_vclocks_store(struct device *dev,
276 				 struct device_attribute *attr,
277 				 const char *buf, size_t count)
278 {
279 	struct ptp_clock *ptp = dev_get_drvdata(dev);
280 	unsigned int *vclock_index;
281 	int err = -EINVAL;
282 	size_t size;
283 	u32 max;
284 
285 	if (kstrtou32(buf, 0, &max) || max == 0)
286 		return -EINVAL;
287 
288 	if (max == ptp->max_vclocks)
289 		return count;
290 
291 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
292 		return -ERESTARTSYS;
293 
294 	if (max < ptp->n_vclocks)
295 		goto out;
296 
297 	size = sizeof(int) * max;
298 	vclock_index = kzalloc(size, GFP_KERNEL);
299 	if (!vclock_index) {
300 		err = -ENOMEM;
301 		goto out;
302 	}
303 
304 	size = sizeof(int) * ptp->n_vclocks;
305 	memcpy(vclock_index, ptp->vclock_index, size);
306 
307 	kfree(ptp->vclock_index);
308 	ptp->vclock_index = vclock_index;
309 	ptp->max_vclocks = max;
310 
311 	mutex_unlock(&ptp->n_vclocks_mux);
312 
313 	return count;
314 out:
315 	mutex_unlock(&ptp->n_vclocks_mux);
316 	return err;
317 }
318 static DEVICE_ATTR_RW(max_vclocks);
319 
320 static struct attribute *ptp_attrs[] = {
321 	&dev_attr_clock_name.attr,
322 
323 	&dev_attr_max_adjustment.attr,
324 	&dev_attr_max_phase_adjustment.attr,
325 	&dev_attr_n_alarms.attr,
326 	&dev_attr_n_external_timestamps.attr,
327 	&dev_attr_n_periodic_outputs.attr,
328 	&dev_attr_n_programmable_pins.attr,
329 	&dev_attr_pps_available.attr,
330 
331 	&dev_attr_extts_enable.attr,
332 	&dev_attr_fifo.attr,
333 	&dev_attr_period.attr,
334 	&dev_attr_pps_enable.attr,
335 	&dev_attr_n_vclocks.attr,
336 	&dev_attr_max_vclocks.attr,
337 	NULL
338 };
339 
340 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
341 					struct attribute *attr, int n)
342 {
343 	struct device *dev = kobj_to_dev(kobj);
344 	struct ptp_clock *ptp = dev_get_drvdata(dev);
345 	struct ptp_clock_info *info = ptp->info;
346 	umode_t mode = attr->mode;
347 
348 	if (attr == &dev_attr_extts_enable.attr ||
349 	    attr == &dev_attr_fifo.attr) {
350 		if (!info->n_ext_ts)
351 			mode = 0;
352 	} else if (attr == &dev_attr_period.attr) {
353 		if (!info->n_per_out)
354 			mode = 0;
355 	} else if (attr == &dev_attr_pps_enable.attr) {
356 		if (!info->pps)
357 			mode = 0;
358 	} else if (attr == &dev_attr_n_vclocks.attr ||
359 		   attr == &dev_attr_max_vclocks.attr) {
360 		if (ptp->is_virtual_clock)
361 			mode = 0;
362 	} else if (attr == &dev_attr_max_phase_adjustment.attr) {
363 		if (!info->adjphase || !info->getmaxphase)
364 			mode = 0;
365 	}
366 
367 	return mode;
368 }
369 
370 static const struct attribute_group ptp_group = {
371 	.is_visible	= ptp_is_attribute_visible,
372 	.attrs		= ptp_attrs,
373 };
374 
375 const struct attribute_group *ptp_groups[] = {
376 	&ptp_group,
377 	NULL
378 };
379 
380 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
381 {
382 	int i;
383 	for (i = 0; i < ptp->info->n_pins; i++) {
384 		if (!strcmp(ptp->info->pin_config[i].name, name))
385 			return i;
386 	}
387 	return -1;
388 }
389 
390 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
391 			    char *page)
392 {
393 	struct ptp_clock *ptp = dev_get_drvdata(dev);
394 	unsigned int func, chan;
395 	int index;
396 
397 	index = ptp_pin_name2index(ptp, attr->attr.name);
398 	if (index < 0)
399 		return -EINVAL;
400 
401 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
402 		return -ERESTARTSYS;
403 
404 	func = ptp->info->pin_config[index].func;
405 	chan = ptp->info->pin_config[index].chan;
406 
407 	mutex_unlock(&ptp->pincfg_mux);
408 
409 	return sysfs_emit(page, "%u %u\n", func, chan);
410 }
411 
412 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
413 			     const char *buf, size_t count)
414 {
415 	struct ptp_clock *ptp = dev_get_drvdata(dev);
416 	unsigned int func, chan;
417 	int cnt, err, index;
418 
419 	cnt = sscanf(buf, "%u %u", &func, &chan);
420 	if (cnt != 2)
421 		return -EINVAL;
422 
423 	index = ptp_pin_name2index(ptp, attr->attr.name);
424 	if (index < 0)
425 		return -EINVAL;
426 
427 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
428 		return -ERESTARTSYS;
429 	err = ptp_set_pinfunc(ptp, index, func, chan);
430 	mutex_unlock(&ptp->pincfg_mux);
431 	if (err)
432 		return err;
433 
434 	return count;
435 }
436 
437 int ptp_populate_pin_groups(struct ptp_clock *ptp)
438 {
439 	struct ptp_clock_info *info = ptp->info;
440 	int err = -ENOMEM, i, n_pins = info->n_pins;
441 
442 	if (!n_pins)
443 		return 0;
444 
445 	ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
446 				    GFP_KERNEL);
447 	if (!ptp->pin_dev_attr)
448 		goto no_dev_attr;
449 
450 	ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
451 	if (!ptp->pin_attr)
452 		goto no_pin_attr;
453 
454 	for (i = 0; i < n_pins; i++) {
455 		struct device_attribute *da = &ptp->pin_dev_attr[i];
456 		sysfs_attr_init(&da->attr);
457 		da->attr.name = info->pin_config[i].name;
458 		da->attr.mode = 0644;
459 		da->show = ptp_pin_show;
460 		da->store = ptp_pin_store;
461 		ptp->pin_attr[i] = &da->attr;
462 	}
463 
464 	ptp->pin_attr_group.name = "pins";
465 	ptp->pin_attr_group.attrs = ptp->pin_attr;
466 
467 	ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
468 
469 	return 0;
470 
471 no_pin_attr:
472 	kfree(ptp->pin_dev_attr);
473 no_dev_attr:
474 	return err;
475 }
476 
477 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
478 {
479 	kfree(ptp->pin_attr);
480 	kfree(ptp->pin_dev_attr);
481 }
482