xref: /openbmc/linux/drivers/usb/dwc3/debugfs.c (revision 31b90347)
1 /**
2  * debugfs.c - DesignWare USB3 DRD Controller DebugFS file
3  *
4  * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
5  *
6  * Authors: Felipe Balbi <balbi@ti.com>,
7  *	    Sebastian Andrzej Siewior <bigeasy@linutronix.de>
8  *
9  * This program is free software: you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2  of
11  * the License as published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/slab.h>
21 #include <linux/ptrace.h>
22 #include <linux/types.h>
23 #include <linux/spinlock.h>
24 #include <linux/debugfs.h>
25 #include <linux/seq_file.h>
26 #include <linux/delay.h>
27 #include <linux/uaccess.h>
28 
29 #include <linux/usb/ch9.h>
30 
31 #include "core.h"
32 #include "gadget.h"
33 #include "io.h"
34 #include "debug.h"
35 
36 #define dump_register(nm)				\
37 {							\
38 	.name	= __stringify(nm),			\
39 	.offset	= DWC3_ ##nm - DWC3_GLOBALS_REGS_START,	\
40 }
41 
42 static const struct debugfs_reg32 dwc3_regs[] = {
43 	dump_register(GSBUSCFG0),
44 	dump_register(GSBUSCFG1),
45 	dump_register(GTXTHRCFG),
46 	dump_register(GRXTHRCFG),
47 	dump_register(GCTL),
48 	dump_register(GEVTEN),
49 	dump_register(GSTS),
50 	dump_register(GSNPSID),
51 	dump_register(GGPIO),
52 	dump_register(GUID),
53 	dump_register(GUCTL),
54 	dump_register(GBUSERRADDR0),
55 	dump_register(GBUSERRADDR1),
56 	dump_register(GPRTBIMAP0),
57 	dump_register(GPRTBIMAP1),
58 	dump_register(GHWPARAMS0),
59 	dump_register(GHWPARAMS1),
60 	dump_register(GHWPARAMS2),
61 	dump_register(GHWPARAMS3),
62 	dump_register(GHWPARAMS4),
63 	dump_register(GHWPARAMS5),
64 	dump_register(GHWPARAMS6),
65 	dump_register(GHWPARAMS7),
66 	dump_register(GDBGFIFOSPACE),
67 	dump_register(GDBGLTSSM),
68 	dump_register(GPRTBIMAP_HS0),
69 	dump_register(GPRTBIMAP_HS1),
70 	dump_register(GPRTBIMAP_FS0),
71 	dump_register(GPRTBIMAP_FS1),
72 
73 	dump_register(GUSB2PHYCFG(0)),
74 	dump_register(GUSB2PHYCFG(1)),
75 	dump_register(GUSB2PHYCFG(2)),
76 	dump_register(GUSB2PHYCFG(3)),
77 	dump_register(GUSB2PHYCFG(4)),
78 	dump_register(GUSB2PHYCFG(5)),
79 	dump_register(GUSB2PHYCFG(6)),
80 	dump_register(GUSB2PHYCFG(7)),
81 	dump_register(GUSB2PHYCFG(8)),
82 	dump_register(GUSB2PHYCFG(9)),
83 	dump_register(GUSB2PHYCFG(10)),
84 	dump_register(GUSB2PHYCFG(11)),
85 	dump_register(GUSB2PHYCFG(12)),
86 	dump_register(GUSB2PHYCFG(13)),
87 	dump_register(GUSB2PHYCFG(14)),
88 	dump_register(GUSB2PHYCFG(15)),
89 
90 	dump_register(GUSB2I2CCTL(0)),
91 	dump_register(GUSB2I2CCTL(1)),
92 	dump_register(GUSB2I2CCTL(2)),
93 	dump_register(GUSB2I2CCTL(3)),
94 	dump_register(GUSB2I2CCTL(4)),
95 	dump_register(GUSB2I2CCTL(5)),
96 	dump_register(GUSB2I2CCTL(6)),
97 	dump_register(GUSB2I2CCTL(7)),
98 	dump_register(GUSB2I2CCTL(8)),
99 	dump_register(GUSB2I2CCTL(9)),
100 	dump_register(GUSB2I2CCTL(10)),
101 	dump_register(GUSB2I2CCTL(11)),
102 	dump_register(GUSB2I2CCTL(12)),
103 	dump_register(GUSB2I2CCTL(13)),
104 	dump_register(GUSB2I2CCTL(14)),
105 	dump_register(GUSB2I2CCTL(15)),
106 
107 	dump_register(GUSB2PHYACC(0)),
108 	dump_register(GUSB2PHYACC(1)),
109 	dump_register(GUSB2PHYACC(2)),
110 	dump_register(GUSB2PHYACC(3)),
111 	dump_register(GUSB2PHYACC(4)),
112 	dump_register(GUSB2PHYACC(5)),
113 	dump_register(GUSB2PHYACC(6)),
114 	dump_register(GUSB2PHYACC(7)),
115 	dump_register(GUSB2PHYACC(8)),
116 	dump_register(GUSB2PHYACC(9)),
117 	dump_register(GUSB2PHYACC(10)),
118 	dump_register(GUSB2PHYACC(11)),
119 	dump_register(GUSB2PHYACC(12)),
120 	dump_register(GUSB2PHYACC(13)),
121 	dump_register(GUSB2PHYACC(14)),
122 	dump_register(GUSB2PHYACC(15)),
123 
124 	dump_register(GUSB3PIPECTL(0)),
125 	dump_register(GUSB3PIPECTL(1)),
126 	dump_register(GUSB3PIPECTL(2)),
127 	dump_register(GUSB3PIPECTL(3)),
128 	dump_register(GUSB3PIPECTL(4)),
129 	dump_register(GUSB3PIPECTL(5)),
130 	dump_register(GUSB3PIPECTL(6)),
131 	dump_register(GUSB3PIPECTL(7)),
132 	dump_register(GUSB3PIPECTL(8)),
133 	dump_register(GUSB3PIPECTL(9)),
134 	dump_register(GUSB3PIPECTL(10)),
135 	dump_register(GUSB3PIPECTL(11)),
136 	dump_register(GUSB3PIPECTL(12)),
137 	dump_register(GUSB3PIPECTL(13)),
138 	dump_register(GUSB3PIPECTL(14)),
139 	dump_register(GUSB3PIPECTL(15)),
140 
141 	dump_register(GTXFIFOSIZ(0)),
142 	dump_register(GTXFIFOSIZ(1)),
143 	dump_register(GTXFIFOSIZ(2)),
144 	dump_register(GTXFIFOSIZ(3)),
145 	dump_register(GTXFIFOSIZ(4)),
146 	dump_register(GTXFIFOSIZ(5)),
147 	dump_register(GTXFIFOSIZ(6)),
148 	dump_register(GTXFIFOSIZ(7)),
149 	dump_register(GTXFIFOSIZ(8)),
150 	dump_register(GTXFIFOSIZ(9)),
151 	dump_register(GTXFIFOSIZ(10)),
152 	dump_register(GTXFIFOSIZ(11)),
153 	dump_register(GTXFIFOSIZ(12)),
154 	dump_register(GTXFIFOSIZ(13)),
155 	dump_register(GTXFIFOSIZ(14)),
156 	dump_register(GTXFIFOSIZ(15)),
157 	dump_register(GTXFIFOSIZ(16)),
158 	dump_register(GTXFIFOSIZ(17)),
159 	dump_register(GTXFIFOSIZ(18)),
160 	dump_register(GTXFIFOSIZ(19)),
161 	dump_register(GTXFIFOSIZ(20)),
162 	dump_register(GTXFIFOSIZ(21)),
163 	dump_register(GTXFIFOSIZ(22)),
164 	dump_register(GTXFIFOSIZ(23)),
165 	dump_register(GTXFIFOSIZ(24)),
166 	dump_register(GTXFIFOSIZ(25)),
167 	dump_register(GTXFIFOSIZ(26)),
168 	dump_register(GTXFIFOSIZ(27)),
169 	dump_register(GTXFIFOSIZ(28)),
170 	dump_register(GTXFIFOSIZ(29)),
171 	dump_register(GTXFIFOSIZ(30)),
172 	dump_register(GTXFIFOSIZ(31)),
173 
174 	dump_register(GRXFIFOSIZ(0)),
175 	dump_register(GRXFIFOSIZ(1)),
176 	dump_register(GRXFIFOSIZ(2)),
177 	dump_register(GRXFIFOSIZ(3)),
178 	dump_register(GRXFIFOSIZ(4)),
179 	dump_register(GRXFIFOSIZ(5)),
180 	dump_register(GRXFIFOSIZ(6)),
181 	dump_register(GRXFIFOSIZ(7)),
182 	dump_register(GRXFIFOSIZ(8)),
183 	dump_register(GRXFIFOSIZ(9)),
184 	dump_register(GRXFIFOSIZ(10)),
185 	dump_register(GRXFIFOSIZ(11)),
186 	dump_register(GRXFIFOSIZ(12)),
187 	dump_register(GRXFIFOSIZ(13)),
188 	dump_register(GRXFIFOSIZ(14)),
189 	dump_register(GRXFIFOSIZ(15)),
190 	dump_register(GRXFIFOSIZ(16)),
191 	dump_register(GRXFIFOSIZ(17)),
192 	dump_register(GRXFIFOSIZ(18)),
193 	dump_register(GRXFIFOSIZ(19)),
194 	dump_register(GRXFIFOSIZ(20)),
195 	dump_register(GRXFIFOSIZ(21)),
196 	dump_register(GRXFIFOSIZ(22)),
197 	dump_register(GRXFIFOSIZ(23)),
198 	dump_register(GRXFIFOSIZ(24)),
199 	dump_register(GRXFIFOSIZ(25)),
200 	dump_register(GRXFIFOSIZ(26)),
201 	dump_register(GRXFIFOSIZ(27)),
202 	dump_register(GRXFIFOSIZ(28)),
203 	dump_register(GRXFIFOSIZ(29)),
204 	dump_register(GRXFIFOSIZ(30)),
205 	dump_register(GRXFIFOSIZ(31)),
206 
207 	dump_register(GEVNTADRLO(0)),
208 	dump_register(GEVNTADRHI(0)),
209 	dump_register(GEVNTSIZ(0)),
210 	dump_register(GEVNTCOUNT(0)),
211 
212 	dump_register(GHWPARAMS8),
213 	dump_register(DCFG),
214 	dump_register(DCTL),
215 	dump_register(DEVTEN),
216 	dump_register(DSTS),
217 	dump_register(DGCMDPAR),
218 	dump_register(DGCMD),
219 	dump_register(DALEPENA),
220 
221 	dump_register(DEPCMDPAR2(0)),
222 	dump_register(DEPCMDPAR2(1)),
223 	dump_register(DEPCMDPAR2(2)),
224 	dump_register(DEPCMDPAR2(3)),
225 	dump_register(DEPCMDPAR2(4)),
226 	dump_register(DEPCMDPAR2(5)),
227 	dump_register(DEPCMDPAR2(6)),
228 	dump_register(DEPCMDPAR2(7)),
229 	dump_register(DEPCMDPAR2(8)),
230 	dump_register(DEPCMDPAR2(9)),
231 	dump_register(DEPCMDPAR2(10)),
232 	dump_register(DEPCMDPAR2(11)),
233 	dump_register(DEPCMDPAR2(12)),
234 	dump_register(DEPCMDPAR2(13)),
235 	dump_register(DEPCMDPAR2(14)),
236 	dump_register(DEPCMDPAR2(15)),
237 	dump_register(DEPCMDPAR2(16)),
238 	dump_register(DEPCMDPAR2(17)),
239 	dump_register(DEPCMDPAR2(18)),
240 	dump_register(DEPCMDPAR2(19)),
241 	dump_register(DEPCMDPAR2(20)),
242 	dump_register(DEPCMDPAR2(21)),
243 	dump_register(DEPCMDPAR2(22)),
244 	dump_register(DEPCMDPAR2(23)),
245 	dump_register(DEPCMDPAR2(24)),
246 	dump_register(DEPCMDPAR2(25)),
247 	dump_register(DEPCMDPAR2(26)),
248 	dump_register(DEPCMDPAR2(27)),
249 	dump_register(DEPCMDPAR2(28)),
250 	dump_register(DEPCMDPAR2(29)),
251 	dump_register(DEPCMDPAR2(30)),
252 	dump_register(DEPCMDPAR2(31)),
253 
254 	dump_register(DEPCMDPAR1(0)),
255 	dump_register(DEPCMDPAR1(1)),
256 	dump_register(DEPCMDPAR1(2)),
257 	dump_register(DEPCMDPAR1(3)),
258 	dump_register(DEPCMDPAR1(4)),
259 	dump_register(DEPCMDPAR1(5)),
260 	dump_register(DEPCMDPAR1(6)),
261 	dump_register(DEPCMDPAR1(7)),
262 	dump_register(DEPCMDPAR1(8)),
263 	dump_register(DEPCMDPAR1(9)),
264 	dump_register(DEPCMDPAR1(10)),
265 	dump_register(DEPCMDPAR1(11)),
266 	dump_register(DEPCMDPAR1(12)),
267 	dump_register(DEPCMDPAR1(13)),
268 	dump_register(DEPCMDPAR1(14)),
269 	dump_register(DEPCMDPAR1(15)),
270 	dump_register(DEPCMDPAR1(16)),
271 	dump_register(DEPCMDPAR1(17)),
272 	dump_register(DEPCMDPAR1(18)),
273 	dump_register(DEPCMDPAR1(19)),
274 	dump_register(DEPCMDPAR1(20)),
275 	dump_register(DEPCMDPAR1(21)),
276 	dump_register(DEPCMDPAR1(22)),
277 	dump_register(DEPCMDPAR1(23)),
278 	dump_register(DEPCMDPAR1(24)),
279 	dump_register(DEPCMDPAR1(25)),
280 	dump_register(DEPCMDPAR1(26)),
281 	dump_register(DEPCMDPAR1(27)),
282 	dump_register(DEPCMDPAR1(28)),
283 	dump_register(DEPCMDPAR1(29)),
284 	dump_register(DEPCMDPAR1(30)),
285 	dump_register(DEPCMDPAR1(31)),
286 
287 	dump_register(DEPCMDPAR0(0)),
288 	dump_register(DEPCMDPAR0(1)),
289 	dump_register(DEPCMDPAR0(2)),
290 	dump_register(DEPCMDPAR0(3)),
291 	dump_register(DEPCMDPAR0(4)),
292 	dump_register(DEPCMDPAR0(5)),
293 	dump_register(DEPCMDPAR0(6)),
294 	dump_register(DEPCMDPAR0(7)),
295 	dump_register(DEPCMDPAR0(8)),
296 	dump_register(DEPCMDPAR0(9)),
297 	dump_register(DEPCMDPAR0(10)),
298 	dump_register(DEPCMDPAR0(11)),
299 	dump_register(DEPCMDPAR0(12)),
300 	dump_register(DEPCMDPAR0(13)),
301 	dump_register(DEPCMDPAR0(14)),
302 	dump_register(DEPCMDPAR0(15)),
303 	dump_register(DEPCMDPAR0(16)),
304 	dump_register(DEPCMDPAR0(17)),
305 	dump_register(DEPCMDPAR0(18)),
306 	dump_register(DEPCMDPAR0(19)),
307 	dump_register(DEPCMDPAR0(20)),
308 	dump_register(DEPCMDPAR0(21)),
309 	dump_register(DEPCMDPAR0(22)),
310 	dump_register(DEPCMDPAR0(23)),
311 	dump_register(DEPCMDPAR0(24)),
312 	dump_register(DEPCMDPAR0(25)),
313 	dump_register(DEPCMDPAR0(26)),
314 	dump_register(DEPCMDPAR0(27)),
315 	dump_register(DEPCMDPAR0(28)),
316 	dump_register(DEPCMDPAR0(29)),
317 	dump_register(DEPCMDPAR0(30)),
318 	dump_register(DEPCMDPAR0(31)),
319 
320 	dump_register(DEPCMD(0)),
321 	dump_register(DEPCMD(1)),
322 	dump_register(DEPCMD(2)),
323 	dump_register(DEPCMD(3)),
324 	dump_register(DEPCMD(4)),
325 	dump_register(DEPCMD(5)),
326 	dump_register(DEPCMD(6)),
327 	dump_register(DEPCMD(7)),
328 	dump_register(DEPCMD(8)),
329 	dump_register(DEPCMD(9)),
330 	dump_register(DEPCMD(10)),
331 	dump_register(DEPCMD(11)),
332 	dump_register(DEPCMD(12)),
333 	dump_register(DEPCMD(13)),
334 	dump_register(DEPCMD(14)),
335 	dump_register(DEPCMD(15)),
336 	dump_register(DEPCMD(16)),
337 	dump_register(DEPCMD(17)),
338 	dump_register(DEPCMD(18)),
339 	dump_register(DEPCMD(19)),
340 	dump_register(DEPCMD(20)),
341 	dump_register(DEPCMD(21)),
342 	dump_register(DEPCMD(22)),
343 	dump_register(DEPCMD(23)),
344 	dump_register(DEPCMD(24)),
345 	dump_register(DEPCMD(25)),
346 	dump_register(DEPCMD(26)),
347 	dump_register(DEPCMD(27)),
348 	dump_register(DEPCMD(28)),
349 	dump_register(DEPCMD(29)),
350 	dump_register(DEPCMD(30)),
351 	dump_register(DEPCMD(31)),
352 
353 	dump_register(OCFG),
354 	dump_register(OCTL),
355 	dump_register(OEVT),
356 	dump_register(OEVTEN),
357 	dump_register(OSTS),
358 };
359 
360 static int dwc3_mode_show(struct seq_file *s, void *unused)
361 {
362 	struct dwc3		*dwc = s->private;
363 	unsigned long		flags;
364 	u32			reg;
365 
366 	spin_lock_irqsave(&dwc->lock, flags);
367 	reg = dwc3_readl(dwc->regs, DWC3_GCTL);
368 	spin_unlock_irqrestore(&dwc->lock, flags);
369 
370 	switch (DWC3_GCTL_PRTCAP(reg)) {
371 	case DWC3_GCTL_PRTCAP_HOST:
372 		seq_printf(s, "host\n");
373 		break;
374 	case DWC3_GCTL_PRTCAP_DEVICE:
375 		seq_printf(s, "device\n");
376 		break;
377 	case DWC3_GCTL_PRTCAP_OTG:
378 		seq_printf(s, "OTG\n");
379 		break;
380 	default:
381 		seq_printf(s, "UNKNOWN %08x\n", DWC3_GCTL_PRTCAP(reg));
382 	}
383 
384 	return 0;
385 }
386 
387 static int dwc3_mode_open(struct inode *inode, struct file *file)
388 {
389 	return single_open(file, dwc3_mode_show, inode->i_private);
390 }
391 
392 static ssize_t dwc3_mode_write(struct file *file,
393 		const char __user *ubuf, size_t count, loff_t *ppos)
394 {
395 	struct seq_file		*s = file->private_data;
396 	struct dwc3		*dwc = s->private;
397 	unsigned long		flags;
398 	u32			mode = 0;
399 	char			buf[32];
400 
401 	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
402 		return -EFAULT;
403 
404 	if (!strncmp(buf, "host", 4))
405 		mode |= DWC3_GCTL_PRTCAP_HOST;
406 
407 	if (!strncmp(buf, "device", 6))
408 		mode |= DWC3_GCTL_PRTCAP_DEVICE;
409 
410 	if (!strncmp(buf, "otg", 3))
411 		mode |= DWC3_GCTL_PRTCAP_OTG;
412 
413 	if (mode) {
414 		spin_lock_irqsave(&dwc->lock, flags);
415 		dwc3_set_mode(dwc, mode);
416 		spin_unlock_irqrestore(&dwc->lock, flags);
417 	}
418 	return count;
419 }
420 
421 static const struct file_operations dwc3_mode_fops = {
422 	.open			= dwc3_mode_open,
423 	.write			= dwc3_mode_write,
424 	.read			= seq_read,
425 	.llseek			= seq_lseek,
426 	.release		= single_release,
427 };
428 
429 static int dwc3_testmode_show(struct seq_file *s, void *unused)
430 {
431 	struct dwc3		*dwc = s->private;
432 	unsigned long		flags;
433 	u32			reg;
434 
435 	spin_lock_irqsave(&dwc->lock, flags);
436 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
437 	reg &= DWC3_DCTL_TSTCTRL_MASK;
438 	reg >>= 1;
439 	spin_unlock_irqrestore(&dwc->lock, flags);
440 
441 	switch (reg) {
442 	case 0:
443 		seq_printf(s, "no test\n");
444 		break;
445 	case TEST_J:
446 		seq_printf(s, "test_j\n");
447 		break;
448 	case TEST_K:
449 		seq_printf(s, "test_k\n");
450 		break;
451 	case TEST_SE0_NAK:
452 		seq_printf(s, "test_se0_nak\n");
453 		break;
454 	case TEST_PACKET:
455 		seq_printf(s, "test_packet\n");
456 		break;
457 	case TEST_FORCE_EN:
458 		seq_printf(s, "test_force_enable\n");
459 		break;
460 	default:
461 		seq_printf(s, "UNKNOWN %d\n", reg);
462 	}
463 
464 	return 0;
465 }
466 
467 static int dwc3_testmode_open(struct inode *inode, struct file *file)
468 {
469 	return single_open(file, dwc3_testmode_show, inode->i_private);
470 }
471 
472 static ssize_t dwc3_testmode_write(struct file *file,
473 		const char __user *ubuf, size_t count, loff_t *ppos)
474 {
475 	struct seq_file		*s = file->private_data;
476 	struct dwc3		*dwc = s->private;
477 	unsigned long		flags;
478 	u32			testmode = 0;
479 	char			buf[32];
480 
481 	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
482 		return -EFAULT;
483 
484 	if (!strncmp(buf, "test_j", 6))
485 		testmode = TEST_J;
486 	else if (!strncmp(buf, "test_k", 6))
487 		testmode = TEST_K;
488 	else if (!strncmp(buf, "test_se0_nak", 12))
489 		testmode = TEST_SE0_NAK;
490 	else if (!strncmp(buf, "test_packet", 11))
491 		testmode = TEST_PACKET;
492 	else if (!strncmp(buf, "test_force_enable", 17))
493 		testmode = TEST_FORCE_EN;
494 	else
495 		testmode = 0;
496 
497 	spin_lock_irqsave(&dwc->lock, flags);
498 	dwc3_gadget_set_test_mode(dwc, testmode);
499 	spin_unlock_irqrestore(&dwc->lock, flags);
500 
501 	return count;
502 }
503 
504 static const struct file_operations dwc3_testmode_fops = {
505 	.open			= dwc3_testmode_open,
506 	.write			= dwc3_testmode_write,
507 	.read			= seq_read,
508 	.llseek			= seq_lseek,
509 	.release		= single_release,
510 };
511 
512 static int dwc3_link_state_show(struct seq_file *s, void *unused)
513 {
514 	struct dwc3		*dwc = s->private;
515 	unsigned long		flags;
516 	enum dwc3_link_state	state;
517 	u32			reg;
518 
519 	spin_lock_irqsave(&dwc->lock, flags);
520 	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
521 	state = DWC3_DSTS_USBLNKST(reg);
522 	spin_unlock_irqrestore(&dwc->lock, flags);
523 
524 	switch (state) {
525 	case DWC3_LINK_STATE_U0:
526 		seq_printf(s, "U0\n");
527 		break;
528 	case DWC3_LINK_STATE_U1:
529 		seq_printf(s, "U1\n");
530 		break;
531 	case DWC3_LINK_STATE_U2:
532 		seq_printf(s, "U2\n");
533 		break;
534 	case DWC3_LINK_STATE_U3:
535 		seq_printf(s, "U3\n");
536 		break;
537 	case DWC3_LINK_STATE_SS_DIS:
538 		seq_printf(s, "SS.Disabled\n");
539 		break;
540 	case DWC3_LINK_STATE_RX_DET:
541 		seq_printf(s, "Rx.Detect\n");
542 		break;
543 	case DWC3_LINK_STATE_SS_INACT:
544 		seq_printf(s, "SS.Inactive\n");
545 		break;
546 	case DWC3_LINK_STATE_POLL:
547 		seq_printf(s, "Poll\n");
548 		break;
549 	case DWC3_LINK_STATE_RECOV:
550 		seq_printf(s, "Recovery\n");
551 		break;
552 	case DWC3_LINK_STATE_HRESET:
553 		seq_printf(s, "HRESET\n");
554 		break;
555 	case DWC3_LINK_STATE_CMPLY:
556 		seq_printf(s, "Compliance\n");
557 		break;
558 	case DWC3_LINK_STATE_LPBK:
559 		seq_printf(s, "Loopback\n");
560 		break;
561 	case DWC3_LINK_STATE_RESET:
562 		seq_printf(s, "Reset\n");
563 		break;
564 	case DWC3_LINK_STATE_RESUME:
565 		seq_printf(s, "Resume\n");
566 		break;
567 	default:
568 		seq_printf(s, "UNKNOWN %d\n", state);
569 	}
570 
571 	return 0;
572 }
573 
574 static int dwc3_link_state_open(struct inode *inode, struct file *file)
575 {
576 	return single_open(file, dwc3_link_state_show, inode->i_private);
577 }
578 
579 static ssize_t dwc3_link_state_write(struct file *file,
580 		const char __user *ubuf, size_t count, loff_t *ppos)
581 {
582 	struct seq_file		*s = file->private_data;
583 	struct dwc3		*dwc = s->private;
584 	unsigned long		flags;
585 	enum dwc3_link_state	state = 0;
586 	char			buf[32];
587 
588 	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
589 		return -EFAULT;
590 
591 	if (!strncmp(buf, "SS.Disabled", 11))
592 		state = DWC3_LINK_STATE_SS_DIS;
593 	else if (!strncmp(buf, "Rx.Detect", 9))
594 		state = DWC3_LINK_STATE_RX_DET;
595 	else if (!strncmp(buf, "SS.Inactive", 11))
596 		state = DWC3_LINK_STATE_SS_INACT;
597 	else if (!strncmp(buf, "Recovery", 8))
598 		state = DWC3_LINK_STATE_RECOV;
599 	else if (!strncmp(buf, "Compliance", 10))
600 		state = DWC3_LINK_STATE_CMPLY;
601 	else if (!strncmp(buf, "Loopback", 8))
602 		state = DWC3_LINK_STATE_LPBK;
603 	else
604 		return -EINVAL;
605 
606 	spin_lock_irqsave(&dwc->lock, flags);
607 	dwc3_gadget_set_link_state(dwc, state);
608 	spin_unlock_irqrestore(&dwc->lock, flags);
609 
610 	return count;
611 }
612 
613 static const struct file_operations dwc3_link_state_fops = {
614 	.open			= dwc3_link_state_open,
615 	.write			= dwc3_link_state_write,
616 	.read			= seq_read,
617 	.llseek			= seq_lseek,
618 	.release		= single_release,
619 };
620 
621 int dwc3_debugfs_init(struct dwc3 *dwc)
622 {
623 	struct dentry		*root;
624 	struct dentry		*file;
625 	int			ret;
626 
627 	root = debugfs_create_dir(dev_name(dwc->dev), NULL);
628 	if (!root) {
629 		ret = -ENOMEM;
630 		goto err0;
631 	}
632 
633 	dwc->root = root;
634 
635 	dwc->regset = kzalloc(sizeof(*dwc->regset), GFP_KERNEL);
636 	if (!dwc->regset) {
637 		ret = -ENOMEM;
638 		goto err1;
639 	}
640 
641 	dwc->regset->regs = dwc3_regs;
642 	dwc->regset->nregs = ARRAY_SIZE(dwc3_regs);
643 	dwc->regset->base = dwc->regs;
644 
645 	file = debugfs_create_regset32("regdump", S_IRUGO, root, dwc->regset);
646 	if (!file) {
647 		ret = -ENOMEM;
648 		goto err1;
649 	}
650 
651 	if (IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)) {
652 		file = debugfs_create_file("mode", S_IRUGO | S_IWUSR, root,
653 				dwc, &dwc3_mode_fops);
654 		if (!file) {
655 			ret = -ENOMEM;
656 			goto err1;
657 		}
658 	}
659 
660 	if (IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE) ||
661 			IS_ENABLED(CONFIG_USB_DWC3_GADGET)) {
662 		file = debugfs_create_file("testmode", S_IRUGO | S_IWUSR, root,
663 				dwc, &dwc3_testmode_fops);
664 		if (!file) {
665 			ret = -ENOMEM;
666 			goto err1;
667 		}
668 
669 		file = debugfs_create_file("link_state", S_IRUGO | S_IWUSR, root,
670 				dwc, &dwc3_link_state_fops);
671 		if (!file) {
672 			ret = -ENOMEM;
673 			goto err1;
674 		}
675 	}
676 
677 	return 0;
678 
679 err1:
680 	debugfs_remove_recursive(root);
681 
682 err0:
683 	return ret;
684 }
685 
686 void dwc3_debugfs_exit(struct dwc3 *dwc)
687 {
688 	debugfs_remove_recursive(dwc->root);
689 	dwc->root = NULL;
690 }
691