xref: /openbmc/linux/drivers/ptp/ptp_sysfs.c (revision 35267cea)
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 snprintf(page, PAGE_SIZE-1, "%s\n", ptp->info->name);
18 }
19 static DEVICE_ATTR_RO(clock_name);
20 
21 #define PTP_SHOW_INT(name, var)						\
22 static ssize_t var##_show(struct device *dev,				\
23 			   struct device_attribute *attr, char *page)	\
24 {									\
25 	struct ptp_clock *ptp = dev_get_drvdata(dev);			\
26 	return snprintf(page, PAGE_SIZE-1, "%d\n", ptp->info->var);	\
27 }									\
28 static DEVICE_ATTR(name, 0444, var##_show, NULL);
29 
30 PTP_SHOW_INT(max_adjustment, max_adj);
31 PTP_SHOW_INT(n_alarms, n_alarm);
32 PTP_SHOW_INT(n_external_timestamps, n_ext_ts);
33 PTP_SHOW_INT(n_periodic_outputs, n_per_out);
34 PTP_SHOW_INT(n_programmable_pins, n_pins);
35 PTP_SHOW_INT(pps_available, pps);
36 
37 static ssize_t extts_enable_store(struct device *dev,
38 				  struct device_attribute *attr,
39 				  const char *buf, size_t count)
40 {
41 	struct ptp_clock *ptp = dev_get_drvdata(dev);
42 	struct ptp_clock_info *ops = ptp->info;
43 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_EXTTS };
44 	int cnt, enable;
45 	int err = -EINVAL;
46 
47 	cnt = sscanf(buf, "%u %d", &req.extts.index, &enable);
48 	if (cnt != 2)
49 		goto out;
50 	if (req.extts.index >= ops->n_ext_ts)
51 		goto out;
52 
53 	err = ops->enable(ops, &req, enable ? 1 : 0);
54 	if (err)
55 		goto out;
56 
57 	return count;
58 out:
59 	return err;
60 }
61 static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store);
62 
63 static ssize_t extts_fifo_show(struct device *dev,
64 			       struct device_attribute *attr, char *page)
65 {
66 	struct ptp_clock *ptp = dev_get_drvdata(dev);
67 	struct timestamp_event_queue *queue = &ptp->tsevq;
68 	struct ptp_extts_event event;
69 	unsigned long flags;
70 	size_t qcnt;
71 	int cnt = 0;
72 
73 	memset(&event, 0, sizeof(event));
74 
75 	if (mutex_lock_interruptible(&ptp->tsevq_mux))
76 		return -ERESTARTSYS;
77 
78 	spin_lock_irqsave(&queue->lock, flags);
79 	qcnt = queue_cnt(queue);
80 	if (qcnt) {
81 		event = queue->buf[queue->head];
82 		queue->head = (queue->head + 1) % PTP_MAX_TIMESTAMPS;
83 	}
84 	spin_unlock_irqrestore(&queue->lock, flags);
85 
86 	if (!qcnt)
87 		goto out;
88 
89 	cnt = snprintf(page, PAGE_SIZE, "%u %lld %u\n",
90 		       event.index, event.t.sec, event.t.nsec);
91 out:
92 	mutex_unlock(&ptp->tsevq_mux);
93 	return cnt;
94 }
95 static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL);
96 
97 static ssize_t period_store(struct device *dev,
98 			    struct device_attribute *attr,
99 			    const char *buf, size_t count)
100 {
101 	struct ptp_clock *ptp = dev_get_drvdata(dev);
102 	struct ptp_clock_info *ops = ptp->info;
103 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PEROUT };
104 	int cnt, enable, err = -EINVAL;
105 
106 	cnt = sscanf(buf, "%u %lld %u %lld %u", &req.perout.index,
107 		     &req.perout.start.sec, &req.perout.start.nsec,
108 		     &req.perout.period.sec, &req.perout.period.nsec);
109 	if (cnt != 5)
110 		goto out;
111 	if (req.perout.index >= ops->n_per_out)
112 		goto out;
113 
114 	enable = req.perout.period.sec || req.perout.period.nsec;
115 	err = ops->enable(ops, &req, enable);
116 	if (err)
117 		goto out;
118 
119 	return count;
120 out:
121 	return err;
122 }
123 static DEVICE_ATTR(period, 0220, NULL, period_store);
124 
125 static ssize_t pps_enable_store(struct device *dev,
126 				struct device_attribute *attr,
127 				const char *buf, size_t count)
128 {
129 	struct ptp_clock *ptp = dev_get_drvdata(dev);
130 	struct ptp_clock_info *ops = ptp->info;
131 	struct ptp_clock_request req = { .type = PTP_CLK_REQ_PPS };
132 	int cnt, enable;
133 	int err = -EINVAL;
134 
135 	if (!capable(CAP_SYS_TIME))
136 		return -EPERM;
137 
138 	cnt = sscanf(buf, "%d", &enable);
139 	if (cnt != 1)
140 		goto out;
141 
142 	err = ops->enable(ops, &req, enable ? 1 : 0);
143 	if (err)
144 		goto out;
145 
146 	return count;
147 out:
148 	return err;
149 }
150 static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store);
151 
152 static int unregister_vclock(struct device *dev, void *data)
153 {
154 	struct ptp_clock *ptp = dev_get_drvdata(dev);
155 	struct ptp_clock_info *info = ptp->info;
156 	struct ptp_vclock *vclock;
157 	u8 *num = data;
158 
159 	vclock = info_to_vclock(info);
160 	dev_info(dev->parent, "delete virtual clock ptp%d\n",
161 		 vclock->clock->index);
162 
163 	ptp_vclock_unregister(vclock);
164 	(*num)--;
165 
166 	/* For break. Not error. */
167 	if (*num == 0)
168 		return -EINVAL;
169 
170 	return 0;
171 }
172 
173 static ssize_t n_vclocks_show(struct device *dev,
174 			      struct device_attribute *attr, char *page)
175 {
176 	struct ptp_clock *ptp = dev_get_drvdata(dev);
177 	ssize_t size;
178 
179 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
180 		return -ERESTARTSYS;
181 
182 	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->n_vclocks);
183 
184 	mutex_unlock(&ptp->n_vclocks_mux);
185 
186 	return size;
187 }
188 
189 static ssize_t n_vclocks_store(struct device *dev,
190 			       struct device_attribute *attr,
191 			       const char *buf, size_t count)
192 {
193 	struct ptp_clock *ptp = dev_get_drvdata(dev);
194 	struct ptp_vclock *vclock;
195 	int err = -EINVAL;
196 	u32 num, i;
197 
198 	if (kstrtou32(buf, 0, &num))
199 		return err;
200 
201 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
202 		return -ERESTARTSYS;
203 
204 	if (num > ptp->max_vclocks) {
205 		dev_err(dev, "max value is %d\n", ptp->max_vclocks);
206 		goto out;
207 	}
208 
209 	/* Need to create more vclocks */
210 	if (num > ptp->n_vclocks) {
211 		for (i = 0; i < num - ptp->n_vclocks; i++) {
212 			vclock = ptp_vclock_register(ptp);
213 			if (!vclock)
214 				goto out;
215 
216 			*(ptp->vclock_index + ptp->n_vclocks + i) =
217 				vclock->clock->index;
218 
219 			dev_info(dev, "new virtual clock ptp%d\n",
220 				 vclock->clock->index);
221 		}
222 	}
223 
224 	/* Need to delete vclocks */
225 	if (num < ptp->n_vclocks) {
226 		i = ptp->n_vclocks - num;
227 		device_for_each_child_reverse(dev, &i,
228 					      unregister_vclock);
229 
230 		for (i = 1; i <= ptp->n_vclocks - num; i++)
231 			*(ptp->vclock_index + ptp->n_vclocks - i) = -1;
232 	}
233 
234 	if (num == 0)
235 		dev_info(dev, "only physical clock in use now\n");
236 	else
237 		dev_info(dev, "guarantee physical clock free running\n");
238 
239 	ptp->n_vclocks = num;
240 	mutex_unlock(&ptp->n_vclocks_mux);
241 
242 	return count;
243 out:
244 	mutex_unlock(&ptp->n_vclocks_mux);
245 	return err;
246 }
247 static DEVICE_ATTR_RW(n_vclocks);
248 
249 static ssize_t max_vclocks_show(struct device *dev,
250 				struct device_attribute *attr, char *page)
251 {
252 	struct ptp_clock *ptp = dev_get_drvdata(dev);
253 	ssize_t size;
254 
255 	size = snprintf(page, PAGE_SIZE - 1, "%u\n", ptp->max_vclocks);
256 
257 	return size;
258 }
259 
260 static ssize_t max_vclocks_store(struct device *dev,
261 				 struct device_attribute *attr,
262 				 const char *buf, size_t count)
263 {
264 	struct ptp_clock *ptp = dev_get_drvdata(dev);
265 	unsigned int *vclock_index;
266 	int err = -EINVAL;
267 	size_t size;
268 	u32 max;
269 
270 	if (kstrtou32(buf, 0, &max) || max == 0)
271 		return -EINVAL;
272 
273 	if (max == ptp->max_vclocks)
274 		return count;
275 
276 	if (mutex_lock_interruptible(&ptp->n_vclocks_mux))
277 		return -ERESTARTSYS;
278 
279 	if (max < ptp->n_vclocks)
280 		goto out;
281 
282 	size = sizeof(int) * max;
283 	vclock_index = kzalloc(size, GFP_KERNEL);
284 	if (!vclock_index) {
285 		err = -ENOMEM;
286 		goto out;
287 	}
288 
289 	size = sizeof(int) * ptp->n_vclocks;
290 	memcpy(vclock_index, ptp->vclock_index, size);
291 
292 	kfree(ptp->vclock_index);
293 	ptp->vclock_index = vclock_index;
294 	ptp->max_vclocks = max;
295 
296 	mutex_unlock(&ptp->n_vclocks_mux);
297 
298 	return count;
299 out:
300 	mutex_unlock(&ptp->n_vclocks_mux);
301 	return err;
302 }
303 static DEVICE_ATTR_RW(max_vclocks);
304 
305 static struct attribute *ptp_attrs[] = {
306 	&dev_attr_clock_name.attr,
307 
308 	&dev_attr_max_adjustment.attr,
309 	&dev_attr_n_alarms.attr,
310 	&dev_attr_n_external_timestamps.attr,
311 	&dev_attr_n_periodic_outputs.attr,
312 	&dev_attr_n_programmable_pins.attr,
313 	&dev_attr_pps_available.attr,
314 
315 	&dev_attr_extts_enable.attr,
316 	&dev_attr_fifo.attr,
317 	&dev_attr_period.attr,
318 	&dev_attr_pps_enable.attr,
319 	&dev_attr_n_vclocks.attr,
320 	&dev_attr_max_vclocks.attr,
321 	NULL
322 };
323 
324 static umode_t ptp_is_attribute_visible(struct kobject *kobj,
325 					struct attribute *attr, int n)
326 {
327 	struct device *dev = kobj_to_dev(kobj);
328 	struct ptp_clock *ptp = dev_get_drvdata(dev);
329 	struct ptp_clock_info *info = ptp->info;
330 	umode_t mode = attr->mode;
331 
332 	if (attr == &dev_attr_extts_enable.attr ||
333 	    attr == &dev_attr_fifo.attr) {
334 		if (!info->n_ext_ts)
335 			mode = 0;
336 	} else if (attr == &dev_attr_period.attr) {
337 		if (!info->n_per_out)
338 			mode = 0;
339 	} else if (attr == &dev_attr_pps_enable.attr) {
340 		if (!info->pps)
341 			mode = 0;
342 	} else if (attr == &dev_attr_n_vclocks.attr ||
343 		   attr == &dev_attr_max_vclocks.attr) {
344 		if (ptp->is_virtual_clock)
345 			mode = 0;
346 	}
347 
348 	return mode;
349 }
350 
351 static const struct attribute_group ptp_group = {
352 	.is_visible	= ptp_is_attribute_visible,
353 	.attrs		= ptp_attrs,
354 };
355 
356 const struct attribute_group *ptp_groups[] = {
357 	&ptp_group,
358 	NULL
359 };
360 
361 static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name)
362 {
363 	int i;
364 	for (i = 0; i < ptp->info->n_pins; i++) {
365 		if (!strcmp(ptp->info->pin_config[i].name, name))
366 			return i;
367 	}
368 	return -1;
369 }
370 
371 static ssize_t ptp_pin_show(struct device *dev, struct device_attribute *attr,
372 			    char *page)
373 {
374 	struct ptp_clock *ptp = dev_get_drvdata(dev);
375 	unsigned int func, chan;
376 	int index;
377 
378 	index = ptp_pin_name2index(ptp, attr->attr.name);
379 	if (index < 0)
380 		return -EINVAL;
381 
382 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
383 		return -ERESTARTSYS;
384 
385 	func = ptp->info->pin_config[index].func;
386 	chan = ptp->info->pin_config[index].chan;
387 
388 	mutex_unlock(&ptp->pincfg_mux);
389 
390 	return snprintf(page, PAGE_SIZE, "%u %u\n", func, chan);
391 }
392 
393 static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr,
394 			     const char *buf, size_t count)
395 {
396 	struct ptp_clock *ptp = dev_get_drvdata(dev);
397 	unsigned int func, chan;
398 	int cnt, err, index;
399 
400 	cnt = sscanf(buf, "%u %u", &func, &chan);
401 	if (cnt != 2)
402 		return -EINVAL;
403 
404 	index = ptp_pin_name2index(ptp, attr->attr.name);
405 	if (index < 0)
406 		return -EINVAL;
407 
408 	if (mutex_lock_interruptible(&ptp->pincfg_mux))
409 		return -ERESTARTSYS;
410 	err = ptp_set_pinfunc(ptp, index, func, chan);
411 	mutex_unlock(&ptp->pincfg_mux);
412 	if (err)
413 		return err;
414 
415 	return count;
416 }
417 
418 int ptp_populate_pin_groups(struct ptp_clock *ptp)
419 {
420 	struct ptp_clock_info *info = ptp->info;
421 	int err = -ENOMEM, i, n_pins = info->n_pins;
422 
423 	if (!n_pins)
424 		return 0;
425 
426 	ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr),
427 				    GFP_KERNEL);
428 	if (!ptp->pin_dev_attr)
429 		goto no_dev_attr;
430 
431 	ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL);
432 	if (!ptp->pin_attr)
433 		goto no_pin_attr;
434 
435 	for (i = 0; i < n_pins; i++) {
436 		struct device_attribute *da = &ptp->pin_dev_attr[i];
437 		sysfs_attr_init(&da->attr);
438 		da->attr.name = info->pin_config[i].name;
439 		da->attr.mode = 0644;
440 		da->show = ptp_pin_show;
441 		da->store = ptp_pin_store;
442 		ptp->pin_attr[i] = &da->attr;
443 	}
444 
445 	ptp->pin_attr_group.name = "pins";
446 	ptp->pin_attr_group.attrs = ptp->pin_attr;
447 
448 	ptp->pin_attr_groups[0] = &ptp->pin_attr_group;
449 
450 	return 0;
451 
452 no_pin_attr:
453 	kfree(ptp->pin_dev_attr);
454 no_dev_attr:
455 	return err;
456 }
457 
458 void ptp_cleanup_pin_groups(struct ptp_clock *ptp)
459 {
460 	kfree(ptp->pin_attr);
461 	kfree(ptp->pin_dev_attr);
462 }
463