xref: /linux/drivers/thunderbolt/debugfs.c (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Debugfs interface
4  *
5  * Copyright (C) 2020, Intel Corporation
6  * Authors: Gil Fine <gil.fine@intel.com>
7  *	    Mika Westerberg <mika.westerberg@linux.intel.com>
8  */
9 
10 #include <linux/debugfs.h>
11 #include <linux/pm_runtime.h>
12 #include <linux/uaccess.h>
13 
14 #include "tb.h"
15 
16 #define PORT_CAP_PCIE_LEN	1
17 #define PORT_CAP_POWER_LEN	2
18 #define PORT_CAP_LANE_LEN	3
19 #define PORT_CAP_USB3_LEN	5
20 #define PORT_CAP_DP_LEN		8
21 #define PORT_CAP_TMU_LEN	8
22 #define PORT_CAP_BASIC_LEN	9
23 #define PORT_CAP_USB4_LEN	20
24 
25 #define SWITCH_CAP_TMU_LEN	26
26 #define SWITCH_CAP_BASIC_LEN	27
27 
28 #define PATH_LEN		2
29 
30 #define COUNTER_SET_LEN		3
31 
32 #define DEBUGFS_ATTR(__space, __write)					\
33 static int __space ## _open(struct inode *inode, struct file *file)	\
34 {									\
35 	return single_open(file, __space ## _show, inode->i_private);	\
36 }									\
37 									\
38 static const struct file_operations __space ## _fops = {		\
39 	.owner = THIS_MODULE,						\
40 	.open = __space ## _open,					\
41 	.release = single_release,					\
42 	.read  = seq_read,						\
43 	.write = __write,						\
44 	.llseek = seq_lseek,						\
45 }
46 
47 #define DEBUGFS_ATTR_RO(__space)					\
48 	DEBUGFS_ATTR(__space, NULL)
49 
50 #define DEBUGFS_ATTR_RW(__space)					\
51 	DEBUGFS_ATTR(__space, __space ## _write)
52 
53 static struct dentry *tb_debugfs_root;
54 
55 static void *validate_and_copy_from_user(const void __user *user_buf,
56 					 size_t *count)
57 {
58 	size_t nbytes;
59 	void *buf;
60 
61 	if (!*count)
62 		return ERR_PTR(-EINVAL);
63 
64 	if (!access_ok(user_buf, *count))
65 		return ERR_PTR(-EFAULT);
66 
67 	buf = (void *)get_zeroed_page(GFP_KERNEL);
68 	if (!buf)
69 		return ERR_PTR(-ENOMEM);
70 
71 	nbytes = min_t(size_t, *count, PAGE_SIZE);
72 	if (copy_from_user(buf, user_buf, nbytes)) {
73 		free_page((unsigned long)buf);
74 		return ERR_PTR(-EFAULT);
75 	}
76 
77 	*count = nbytes;
78 	return buf;
79 }
80 
81 static bool parse_line(char **line, u32 *offs, u32 *val, int short_fmt_len,
82 		       int long_fmt_len)
83 {
84 	char *token;
85 	u32 v[5];
86 	int ret;
87 
88 	token = strsep(line, "\n");
89 	if (!token)
90 		return false;
91 
92 	/*
93 	 * For Adapter/Router configuration space:
94 	 * Short format is: offset value\n
95 	 *		    v[0]   v[1]
96 	 * Long format as produced from the read side:
97 	 * offset relative_offset cap_id vs_cap_id value\n
98 	 * v[0]   v[1]            v[2]   v[3]      v[4]
99 	 *
100 	 * For Counter configuration space:
101 	 * Short format is: offset\n
102 	 *		    v[0]
103 	 * Long format as produced from the read side:
104 	 * offset relative_offset counter_id value\n
105 	 * v[0]   v[1]            v[2]       v[3]
106 	 */
107 	ret = sscanf(token, "%i %i %i %i %i", &v[0], &v[1], &v[2], &v[3], &v[4]);
108 	/* In case of Counters, clear counter, "val" content is NA */
109 	if (ret == short_fmt_len) {
110 		*offs = v[0];
111 		*val = v[short_fmt_len - 1];
112 		return true;
113 	} else if (ret == long_fmt_len) {
114 		*offs = v[0];
115 		*val = v[long_fmt_len - 1];
116 		return true;
117 	}
118 
119 	return false;
120 }
121 
122 #if IS_ENABLED(CONFIG_USB4_DEBUGFS_WRITE)
123 static ssize_t regs_write(struct tb_switch *sw, struct tb_port *port,
124 			  const char __user *user_buf, size_t count,
125 			  loff_t *ppos)
126 {
127 	struct tb *tb = sw->tb;
128 	char *line, *buf;
129 	u32 val, offset;
130 	int ret = 0;
131 
132 	buf = validate_and_copy_from_user(user_buf, &count);
133 	if (IS_ERR(buf))
134 		return PTR_ERR(buf);
135 
136 	pm_runtime_get_sync(&sw->dev);
137 
138 	if (mutex_lock_interruptible(&tb->lock)) {
139 		ret = -ERESTARTSYS;
140 		goto out;
141 	}
142 
143 	/* User did hardware changes behind the driver's back */
144 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
145 
146 	line = buf;
147 	while (parse_line(&line, &offset, &val, 2, 5)) {
148 		if (port)
149 			ret = tb_port_write(port, &val, TB_CFG_PORT, offset, 1);
150 		else
151 			ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, offset, 1);
152 		if (ret)
153 			break;
154 	}
155 
156 	mutex_unlock(&tb->lock);
157 
158 out:
159 	pm_runtime_mark_last_busy(&sw->dev);
160 	pm_runtime_put_autosuspend(&sw->dev);
161 	free_page((unsigned long)buf);
162 
163 	return ret < 0 ? ret : count;
164 }
165 
166 static ssize_t port_regs_write(struct file *file, const char __user *user_buf,
167 			       size_t count, loff_t *ppos)
168 {
169 	struct seq_file *s = file->private_data;
170 	struct tb_port *port = s->private;
171 
172 	return regs_write(port->sw, port, user_buf, count, ppos);
173 }
174 
175 static ssize_t switch_regs_write(struct file *file, const char __user *user_buf,
176 				 size_t count, loff_t *ppos)
177 {
178 	struct seq_file *s = file->private_data;
179 	struct tb_switch *sw = s->private;
180 
181 	return regs_write(sw, NULL, user_buf, count, ppos);
182 }
183 #define DEBUGFS_MODE		0600
184 #else
185 #define port_regs_write		NULL
186 #define switch_regs_write	NULL
187 #define DEBUGFS_MODE		0400
188 #endif
189 
190 static int port_clear_all_counters(struct tb_port *port)
191 {
192 	u32 *buf;
193 	int ret;
194 
195 	buf = kcalloc(COUNTER_SET_LEN * port->config.max_counters, sizeof(u32),
196 		      GFP_KERNEL);
197 	if (!buf)
198 		return -ENOMEM;
199 
200 	ret = tb_port_write(port, buf, TB_CFG_COUNTERS, 0,
201 			    COUNTER_SET_LEN * port->config.max_counters);
202 	kfree(buf);
203 
204 	return ret;
205 }
206 
207 static ssize_t counters_write(struct file *file, const char __user *user_buf,
208 			      size_t count, loff_t *ppos)
209 {
210 	struct seq_file *s = file->private_data;
211 	struct tb_port *port = s->private;
212 	struct tb_switch *sw = port->sw;
213 	struct tb *tb = port->sw->tb;
214 	char *buf;
215 	int ret;
216 
217 	buf = validate_and_copy_from_user(user_buf, &count);
218 	if (IS_ERR(buf))
219 		return PTR_ERR(buf);
220 
221 	pm_runtime_get_sync(&sw->dev);
222 
223 	if (mutex_lock_interruptible(&tb->lock)) {
224 		ret = -ERESTARTSYS;
225 		goto out;
226 	}
227 
228 	/* If written delimiter only, clear all counters in one shot */
229 	if (buf[0] == '\n') {
230 		ret = port_clear_all_counters(port);
231 	} else  {
232 		char *line = buf;
233 		u32 val, offset;
234 
235 		ret = -EINVAL;
236 		while (parse_line(&line, &offset, &val, 1, 4)) {
237 			ret = tb_port_write(port, &val, TB_CFG_COUNTERS,
238 					    offset, 1);
239 			if (ret)
240 				break;
241 		}
242 	}
243 
244 	mutex_unlock(&tb->lock);
245 
246 out:
247 	pm_runtime_mark_last_busy(&sw->dev);
248 	pm_runtime_put_autosuspend(&sw->dev);
249 	free_page((unsigned long)buf);
250 
251 	return ret < 0 ? ret : count;
252 }
253 
254 static void cap_show_by_dw(struct seq_file *s, struct tb_switch *sw,
255 			   struct tb_port *port, unsigned int cap,
256 			   unsigned int offset, u8 cap_id, u8 vsec_id,
257 			   int dwords)
258 {
259 	int i, ret;
260 	u32 data;
261 
262 	for (i = 0; i < dwords; i++) {
263 		if (port)
264 			ret = tb_port_read(port, &data, TB_CFG_PORT, cap + offset + i, 1);
265 		else
266 			ret = tb_sw_read(sw, &data, TB_CFG_SWITCH, cap + offset + i, 1);
267 		if (ret) {
268 			seq_printf(s, "0x%04x <not accessible>\n", cap + offset + i);
269 			continue;
270 		}
271 
272 		seq_printf(s, "0x%04x %4d 0x%02x 0x%02x 0x%08x\n", cap + offset + i,
273 			   offset + i, cap_id, vsec_id, data);
274 	}
275 }
276 
277 static void cap_show(struct seq_file *s, struct tb_switch *sw,
278 		     struct tb_port *port, unsigned int cap, u8 cap_id,
279 		     u8 vsec_id, int length)
280 {
281 	int ret, offset = 0;
282 
283 	while (length > 0) {
284 		int i, dwords = min(length, TB_MAX_CONFIG_RW_LENGTH);
285 		u32 data[TB_MAX_CONFIG_RW_LENGTH];
286 
287 		if (port)
288 			ret = tb_port_read(port, data, TB_CFG_PORT, cap + offset,
289 					   dwords);
290 		else
291 			ret = tb_sw_read(sw, data, TB_CFG_SWITCH, cap + offset, dwords);
292 		if (ret) {
293 			cap_show_by_dw(s, sw, port, cap, offset, cap_id, vsec_id, length);
294 			return;
295 		}
296 
297 		for (i = 0; i < dwords; i++) {
298 			seq_printf(s, "0x%04x %4d 0x%02x 0x%02x 0x%08x\n",
299 				   cap + offset + i, offset + i,
300 				   cap_id, vsec_id, data[i]);
301 		}
302 
303 		length -= dwords;
304 		offset += dwords;
305 	}
306 }
307 
308 static void port_cap_show(struct tb_port *port, struct seq_file *s,
309 			  unsigned int cap)
310 {
311 	struct tb_cap_any header;
312 	u8 vsec_id = 0;
313 	size_t length;
314 	int ret;
315 
316 	ret = tb_port_read(port, &header, TB_CFG_PORT, cap, 1);
317 	if (ret) {
318 		seq_printf(s, "0x%04x <capability read failed>\n", cap);
319 		return;
320 	}
321 
322 	switch (header.basic.cap) {
323 	case TB_PORT_CAP_PHY:
324 		length = PORT_CAP_LANE_LEN;
325 		break;
326 
327 	case TB_PORT_CAP_TIME1:
328 		length = PORT_CAP_TMU_LEN;
329 		break;
330 
331 	case TB_PORT_CAP_POWER:
332 		length = PORT_CAP_POWER_LEN;
333 		break;
334 
335 	case TB_PORT_CAP_ADAP:
336 		if (tb_port_is_pcie_down(port) || tb_port_is_pcie_up(port)) {
337 			length = PORT_CAP_PCIE_LEN;
338 		} else if (tb_port_is_dpin(port) || tb_port_is_dpout(port)) {
339 			length = PORT_CAP_DP_LEN;
340 		} else if (tb_port_is_usb3_down(port) ||
341 			   tb_port_is_usb3_up(port)) {
342 			length = PORT_CAP_USB3_LEN;
343 		} else {
344 			seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
345 				   cap, header.basic.cap);
346 			return;
347 		}
348 		break;
349 
350 	case TB_PORT_CAP_VSE:
351 		if (!header.extended_short.length) {
352 			ret = tb_port_read(port, (u32 *)&header + 1, TB_CFG_PORT,
353 					   cap + 1, 1);
354 			if (ret) {
355 				seq_printf(s, "0x%04x <capability read failed>\n",
356 					   cap + 1);
357 				return;
358 			}
359 			length = header.extended_long.length;
360 			vsec_id = header.extended_short.vsec_id;
361 		} else {
362 			length = header.extended_short.length;
363 			vsec_id = header.extended_short.vsec_id;
364 		}
365 		break;
366 
367 	case TB_PORT_CAP_USB4:
368 		length = PORT_CAP_USB4_LEN;
369 		break;
370 
371 	default:
372 		seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
373 			   cap, header.basic.cap);
374 		return;
375 	}
376 
377 	cap_show(s, NULL, port, cap, header.basic.cap, vsec_id, length);
378 }
379 
380 static void port_caps_show(struct tb_port *port, struct seq_file *s)
381 {
382 	int cap;
383 
384 	cap = tb_port_next_cap(port, 0);
385 	while (cap > 0) {
386 		port_cap_show(port, s, cap);
387 		cap = tb_port_next_cap(port, cap);
388 	}
389 }
390 
391 static int port_basic_regs_show(struct tb_port *port, struct seq_file *s)
392 {
393 	u32 data[PORT_CAP_BASIC_LEN];
394 	int ret, i;
395 
396 	ret = tb_port_read(port, data, TB_CFG_PORT, 0, ARRAY_SIZE(data));
397 	if (ret)
398 		return ret;
399 
400 	for (i = 0; i < ARRAY_SIZE(data); i++)
401 		seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
402 
403 	return 0;
404 }
405 
406 static int port_regs_show(struct seq_file *s, void *not_used)
407 {
408 	struct tb_port *port = s->private;
409 	struct tb_switch *sw = port->sw;
410 	struct tb *tb = sw->tb;
411 	int ret;
412 
413 	pm_runtime_get_sync(&sw->dev);
414 
415 	if (mutex_lock_interruptible(&tb->lock)) {
416 		ret = -ERESTARTSYS;
417 		goto out_rpm_put;
418 	}
419 
420 	seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
421 
422 	ret = port_basic_regs_show(port, s);
423 	if (ret)
424 		goto out_unlock;
425 
426 	port_caps_show(port, s);
427 
428 out_unlock:
429 	mutex_unlock(&tb->lock);
430 out_rpm_put:
431 	pm_runtime_mark_last_busy(&sw->dev);
432 	pm_runtime_put_autosuspend(&sw->dev);
433 
434 	return ret;
435 }
436 DEBUGFS_ATTR_RW(port_regs);
437 
438 static void switch_cap_show(struct tb_switch *sw, struct seq_file *s,
439 			    unsigned int cap)
440 {
441 	struct tb_cap_any header;
442 	int ret, length;
443 	u8 vsec_id = 0;
444 
445 	ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, cap, 1);
446 	if (ret) {
447 		seq_printf(s, "0x%04x <capability read failed>\n", cap);
448 		return;
449 	}
450 
451 	if (header.basic.cap == TB_SWITCH_CAP_VSE) {
452 		if (!header.extended_short.length) {
453 			ret = tb_sw_read(sw, (u32 *)&header + 1, TB_CFG_SWITCH,
454 					 cap + 1, 1);
455 			if (ret) {
456 				seq_printf(s, "0x%04x <capability read failed>\n",
457 					   cap + 1);
458 				return;
459 			}
460 			length = header.extended_long.length;
461 		} else {
462 			length = header.extended_short.length;
463 		}
464 		vsec_id = header.extended_short.vsec_id;
465 	} else {
466 		if (header.basic.cap == TB_SWITCH_CAP_TMU) {
467 			length = SWITCH_CAP_TMU_LEN;
468 		} else  {
469 			seq_printf(s, "0x%04x <unknown capability 0x%02x>\n",
470 				   cap, header.basic.cap);
471 			return;
472 		}
473 	}
474 
475 	cap_show(s, sw, NULL, cap, header.basic.cap, vsec_id, length);
476 }
477 
478 static void switch_caps_show(struct tb_switch *sw, struct seq_file *s)
479 {
480 	int cap;
481 
482 	cap = tb_switch_next_cap(sw, 0);
483 	while (cap > 0) {
484 		switch_cap_show(sw, s, cap);
485 		cap = tb_switch_next_cap(sw, cap);
486 	}
487 }
488 
489 static int switch_basic_regs_show(struct tb_switch *sw, struct seq_file *s)
490 {
491 	u32 data[SWITCH_CAP_BASIC_LEN];
492 	size_t dwords;
493 	int ret, i;
494 
495 	/* Only USB4 has the additional registers */
496 	if (tb_switch_is_usb4(sw))
497 		dwords = ARRAY_SIZE(data);
498 	else
499 		dwords = 7;
500 
501 	ret = tb_sw_read(sw, data, TB_CFG_SWITCH, 0, dwords);
502 	if (ret)
503 		return ret;
504 
505 	for (i = 0; i < dwords; i++)
506 		seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
507 
508 	return 0;
509 }
510 
511 static int switch_regs_show(struct seq_file *s, void *not_used)
512 {
513 	struct tb_switch *sw = s->private;
514 	struct tb *tb = sw->tb;
515 	int ret;
516 
517 	pm_runtime_get_sync(&sw->dev);
518 
519 	if (mutex_lock_interruptible(&tb->lock)) {
520 		ret = -ERESTARTSYS;
521 		goto out_rpm_put;
522 	}
523 
524 	seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
525 
526 	ret = switch_basic_regs_show(sw, s);
527 	if (ret)
528 		goto out_unlock;
529 
530 	switch_caps_show(sw, s);
531 
532 out_unlock:
533 	mutex_unlock(&tb->lock);
534 out_rpm_put:
535 	pm_runtime_mark_last_busy(&sw->dev);
536 	pm_runtime_put_autosuspend(&sw->dev);
537 
538 	return ret;
539 }
540 DEBUGFS_ATTR_RW(switch_regs);
541 
542 static int path_show_one(struct tb_port *port, struct seq_file *s, int hopid)
543 {
544 	u32 data[PATH_LEN];
545 	int ret, i;
546 
547 	ret = tb_port_read(port, data, TB_CFG_HOPS, hopid * PATH_LEN,
548 			   ARRAY_SIZE(data));
549 	if (ret) {
550 		seq_printf(s, "0x%04x <not accessible>\n", hopid * PATH_LEN);
551 		return ret;
552 	}
553 
554 	for (i = 0; i < ARRAY_SIZE(data); i++) {
555 		seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
556 			   hopid * PATH_LEN + i, i, hopid, data[i]);
557 	}
558 
559 	return 0;
560 }
561 
562 static int path_show(struct seq_file *s, void *not_used)
563 {
564 	struct tb_port *port = s->private;
565 	struct tb_switch *sw = port->sw;
566 	struct tb *tb = sw->tb;
567 	int start, i, ret = 0;
568 
569 	pm_runtime_get_sync(&sw->dev);
570 
571 	if (mutex_lock_interruptible(&tb->lock)) {
572 		ret = -ERESTARTSYS;
573 		goto out_rpm_put;
574 	}
575 
576 	seq_puts(s, "# offset relative_offset in_hop_id value\n");
577 
578 	/* NHI and lane adapters have entry for path 0 */
579 	if (tb_port_is_null(port) || tb_port_is_nhi(port)) {
580 		ret = path_show_one(port, s, 0);
581 		if (ret)
582 			goto out_unlock;
583 	}
584 
585 	start = tb_port_is_nhi(port) ? 1 : TB_PATH_MIN_HOPID;
586 
587 	for (i = start; i <= port->config.max_in_hop_id; i++) {
588 		ret = path_show_one(port, s, i);
589 		if (ret)
590 			break;
591 	}
592 
593 out_unlock:
594 	mutex_unlock(&tb->lock);
595 out_rpm_put:
596 	pm_runtime_mark_last_busy(&sw->dev);
597 	pm_runtime_put_autosuspend(&sw->dev);
598 
599 	return ret;
600 }
601 DEBUGFS_ATTR_RO(path);
602 
603 static int counter_set_regs_show(struct tb_port *port, struct seq_file *s,
604 				 int counter)
605 {
606 	u32 data[COUNTER_SET_LEN];
607 	int ret, i;
608 
609 	ret = tb_port_read(port, data, TB_CFG_COUNTERS,
610 			   counter * COUNTER_SET_LEN, ARRAY_SIZE(data));
611 	if (ret) {
612 		seq_printf(s, "0x%04x <not accessible>\n",
613 			   counter * COUNTER_SET_LEN);
614 		return ret;
615 	}
616 
617 	for (i = 0; i < ARRAY_SIZE(data); i++) {
618 		seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
619 			   counter * COUNTER_SET_LEN + i, i, counter, data[i]);
620 	}
621 
622 	return 0;
623 }
624 
625 static int counters_show(struct seq_file *s, void *not_used)
626 {
627 	struct tb_port *port = s->private;
628 	struct tb_switch *sw = port->sw;
629 	struct tb *tb = sw->tb;
630 	int i, ret = 0;
631 
632 	pm_runtime_get_sync(&sw->dev);
633 
634 	if (mutex_lock_interruptible(&tb->lock)) {
635 		ret = -ERESTARTSYS;
636 		goto out;
637 	}
638 
639 	seq_puts(s, "# offset relative_offset counter_id value\n");
640 
641 	for (i = 0; i < port->config.max_counters; i++) {
642 		ret = counter_set_regs_show(port, s, i);
643 		if (ret)
644 			break;
645 	}
646 
647 	mutex_unlock(&tb->lock);
648 
649 out:
650 	pm_runtime_mark_last_busy(&sw->dev);
651 	pm_runtime_put_autosuspend(&sw->dev);
652 
653 	return ret;
654 }
655 DEBUGFS_ATTR_RW(counters);
656 
657 /**
658  * tb_switch_debugfs_init() - Add debugfs entries for router
659  * @sw: Pointer to the router
660  *
661  * Adds debugfs directories and files for given router.
662  */
663 void tb_switch_debugfs_init(struct tb_switch *sw)
664 {
665 	struct dentry *debugfs_dir;
666 	struct tb_port *port;
667 
668 	debugfs_dir = debugfs_create_dir(dev_name(&sw->dev), tb_debugfs_root);
669 	sw->debugfs_dir = debugfs_dir;
670 	debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir, sw,
671 			    &switch_regs_fops);
672 
673 	tb_switch_for_each_port(sw, port) {
674 		struct dentry *debugfs_dir;
675 		char dir_name[10];
676 
677 		if (port->disabled)
678 			continue;
679 		if (port->config.type == TB_TYPE_INACTIVE)
680 			continue;
681 
682 		snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
683 		debugfs_dir = debugfs_create_dir(dir_name, sw->debugfs_dir);
684 		debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir,
685 				    port, &port_regs_fops);
686 		debugfs_create_file("path", 0400, debugfs_dir, port,
687 				    &path_fops);
688 		if (port->config.counters_support)
689 			debugfs_create_file("counters", 0600, debugfs_dir, port,
690 					    &counters_fops);
691 	}
692 }
693 
694 /**
695  * tb_switch_debugfs_remove() - Remove all router debugfs entries
696  * @sw: Pointer to the router
697  *
698  * Removes all previously added debugfs entries under this router.
699  */
700 void tb_switch_debugfs_remove(struct tb_switch *sw)
701 {
702 	debugfs_remove_recursive(sw->debugfs_dir);
703 }
704 
705 /**
706  * tb_service_debugfs_init() - Add debugfs directory for service
707  * @svc: Thunderbolt service pointer
708  *
709  * Adds debugfs directory for service.
710  */
711 void tb_service_debugfs_init(struct tb_service *svc)
712 {
713 	svc->debugfs_dir = debugfs_create_dir(dev_name(&svc->dev),
714 					      tb_debugfs_root);
715 }
716 
717 /**
718  * tb_service_debugfs_remove() - Remove service debugfs directory
719  * @svc: Thunderbolt service pointer
720  *
721  * Removes the previously created debugfs directory for @svc.
722  */
723 void tb_service_debugfs_remove(struct tb_service *svc)
724 {
725 	debugfs_remove_recursive(svc->debugfs_dir);
726 	svc->debugfs_dir = NULL;
727 }
728 
729 void tb_debugfs_init(void)
730 {
731 	tb_debugfs_root = debugfs_create_dir("thunderbolt", NULL);
732 }
733 
734 void tb_debugfs_exit(void)
735 {
736 	debugfs_remove_recursive(tb_debugfs_root);
737 }
738