xref: /linux/drivers/usb/host/ohci-dbg.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
1 /*
2  * OHCI HCD (Host Controller Driver) for USB.
3  *
4  * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
5  * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
6  *
7  * This file is licenced under the GPL.
8  */
9 
10 /*-------------------------------------------------------------------------*/
11 
12 #define edstring(ed_type) ({ char *temp; \
13 	switch (ed_type) { \
14 	case PIPE_CONTROL:	temp = "ctrl"; break; \
15 	case PIPE_BULK:		temp = "bulk"; break; \
16 	case PIPE_INTERRUPT:	temp = "intr"; break; \
17 	default:		temp = "isoc"; break; \
18 	} temp;})
19 #define pipestring(pipe) edstring(usb_pipetype(pipe))
20 
21 
22 #define ohci_dbg_sw(ohci, next, size, format, arg...) \
23 	do { \
24 	if (next != NULL) { \
25 		unsigned s_len; \
26 		s_len = scnprintf (*next, *size, format, ## arg ); \
27 		*size -= s_len; *next += s_len; \
28 	} else \
29 		ohci_dbg(ohci,format, ## arg ); \
30 	} while (0);
31 
32 /* Version for use where "next" is the address of a local variable */
33 #define ohci_dbg_nosw(ohci, next, size, format, arg...) \
34 	do { \
35 		unsigned s_len; \
36 		s_len = scnprintf(*next, *size, format, ## arg); \
37 		*size -= s_len; *next += s_len; \
38 	} while (0);
39 
40 
41 static void ohci_dump_intr_mask (
42 	struct ohci_hcd *ohci,
43 	char *label,
44 	u32 mask,
45 	char **next,
46 	unsigned *size)
47 {
48 	ohci_dbg_sw (ohci, next, size, "%s 0x%08x%s%s%s%s%s%s%s%s%s\n",
49 		label,
50 		mask,
51 		(mask & OHCI_INTR_MIE) ? " MIE" : "",
52 		(mask & OHCI_INTR_OC) ? " OC" : "",
53 		(mask & OHCI_INTR_RHSC) ? " RHSC" : "",
54 		(mask & OHCI_INTR_FNO) ? " FNO" : "",
55 		(mask & OHCI_INTR_UE) ? " UE" : "",
56 		(mask & OHCI_INTR_RD) ? " RD" : "",
57 		(mask & OHCI_INTR_SF) ? " SF" : "",
58 		(mask & OHCI_INTR_WDH) ? " WDH" : "",
59 		(mask & OHCI_INTR_SO) ? " SO" : ""
60 		);
61 }
62 
63 static void maybe_print_eds (
64 	struct ohci_hcd *ohci,
65 	char *label,
66 	u32 value,
67 	char **next,
68 	unsigned *size)
69 {
70 	if (value)
71 		ohci_dbg_sw (ohci, next, size, "%s %08x\n", label, value);
72 }
73 
74 static char *hcfs2string (int state)
75 {
76 	switch (state) {
77 		case OHCI_USB_RESET:	return "reset";
78 		case OHCI_USB_RESUME:	return "resume";
79 		case OHCI_USB_OPER:	return "operational";
80 		case OHCI_USB_SUSPEND:	return "suspend";
81 	}
82 	return "?";
83 }
84 
85 static const char *rh_state_string(struct ohci_hcd *ohci)
86 {
87 	switch (ohci->rh_state) {
88 	case OHCI_RH_HALTED:
89 		return "halted";
90 	case OHCI_RH_SUSPENDED:
91 		return "suspended";
92 	case OHCI_RH_RUNNING:
93 		return "running";
94 	}
95 	return "?";
96 }
97 
98 // dump control and status registers
99 static void
100 ohci_dump_status (struct ohci_hcd *controller, char **next, unsigned *size)
101 {
102 	struct ohci_regs __iomem *regs = controller->regs;
103 	u32			temp;
104 
105 	temp = ohci_readl (controller, &regs->revision) & 0xff;
106 	ohci_dbg_sw (controller, next, size,
107 		"OHCI %d.%d, %s legacy support registers, rh state %s\n",
108 		0x03 & (temp >> 4), (temp & 0x0f),
109 		(temp & 0x0100) ? "with" : "NO",
110 		rh_state_string(controller));
111 
112 	temp = ohci_readl (controller, &regs->control);
113 	ohci_dbg_sw (controller, next, size,
114 		"control 0x%03x%s%s%s HCFS=%s%s%s%s%s CBSR=%d\n",
115 		temp,
116 		(temp & OHCI_CTRL_RWE) ? " RWE" : "",
117 		(temp & OHCI_CTRL_RWC) ? " RWC" : "",
118 		(temp & OHCI_CTRL_IR) ? " IR" : "",
119 		hcfs2string (temp & OHCI_CTRL_HCFS),
120 		(temp & OHCI_CTRL_BLE) ? " BLE" : "",
121 		(temp & OHCI_CTRL_CLE) ? " CLE" : "",
122 		(temp & OHCI_CTRL_IE) ? " IE" : "",
123 		(temp & OHCI_CTRL_PLE) ? " PLE" : "",
124 		temp & OHCI_CTRL_CBSR
125 		);
126 
127 	temp = ohci_readl (controller, &regs->cmdstatus);
128 	ohci_dbg_sw (controller, next, size,
129 		"cmdstatus 0x%05x SOC=%d%s%s%s%s\n", temp,
130 		(temp & OHCI_SOC) >> 16,
131 		(temp & OHCI_OCR) ? " OCR" : "",
132 		(temp & OHCI_BLF) ? " BLF" : "",
133 		(temp & OHCI_CLF) ? " CLF" : "",
134 		(temp & OHCI_HCR) ? " HCR" : ""
135 		);
136 
137 	ohci_dump_intr_mask (controller, "intrstatus",
138 			ohci_readl (controller, &regs->intrstatus),
139 			next, size);
140 	ohci_dump_intr_mask (controller, "intrenable",
141 			ohci_readl (controller, &regs->intrenable),
142 			next, size);
143 	// intrdisable always same as intrenable
144 
145 	maybe_print_eds (controller, "ed_periodcurrent",
146 			ohci_readl (controller, &regs->ed_periodcurrent),
147 			next, size);
148 
149 	maybe_print_eds (controller, "ed_controlhead",
150 			ohci_readl (controller, &regs->ed_controlhead),
151 			next, size);
152 	maybe_print_eds (controller, "ed_controlcurrent",
153 			ohci_readl (controller, &regs->ed_controlcurrent),
154 			next, size);
155 
156 	maybe_print_eds (controller, "ed_bulkhead",
157 			ohci_readl (controller, &regs->ed_bulkhead),
158 			next, size);
159 	maybe_print_eds (controller, "ed_bulkcurrent",
160 			ohci_readl (controller, &regs->ed_bulkcurrent),
161 			next, size);
162 
163 	maybe_print_eds (controller, "donehead",
164 			ohci_readl (controller, &regs->donehead), next, size);
165 }
166 
167 #define dbg_port_sw(hc,num,value,next,size) \
168 	ohci_dbg_sw (hc, next, size, \
169 		"roothub.portstatus [%d] " \
170 		"0x%08x%s%s%s%s%s%s%s%s%s%s%s%s\n", \
171 		num, temp, \
172 		(temp & RH_PS_PRSC) ? " PRSC" : "", \
173 		(temp & RH_PS_OCIC) ? " OCIC" : "", \
174 		(temp & RH_PS_PSSC) ? " PSSC" : "", \
175 		(temp & RH_PS_PESC) ? " PESC" : "", \
176 		(temp & RH_PS_CSC) ? " CSC" : "", \
177 		\
178 		(temp & RH_PS_LSDA) ? " LSDA" : "", \
179 		(temp & RH_PS_PPS) ? " PPS" : "", \
180 		(temp & RH_PS_PRS) ? " PRS" : "", \
181 		(temp & RH_PS_POCI) ? " POCI" : "", \
182 		(temp & RH_PS_PSS) ? " PSS" : "", \
183 		\
184 		(temp & RH_PS_PES) ? " PES" : "", \
185 		(temp & RH_PS_CCS) ? " CCS" : "" \
186 		);
187 
188 
189 static void
190 ohci_dump_roothub (
191 	struct ohci_hcd *controller,
192 	int verbose,
193 	char **next,
194 	unsigned *size)
195 {
196 	u32			temp, i;
197 
198 	temp = roothub_a (controller);
199 	if (temp == ~(u32)0)
200 		return;
201 
202 	if (verbose) {
203 		ohci_dbg_sw (controller, next, size,
204 			"roothub.a %08x POTPGT=%d%s%s%s%s%s NDP=%d(%d)\n", temp,
205 			((temp & RH_A_POTPGT) >> 24) & 0xff,
206 			(temp & RH_A_NOCP) ? " NOCP" : "",
207 			(temp & RH_A_OCPM) ? " OCPM" : "",
208 			(temp & RH_A_DT) ? " DT" : "",
209 			(temp & RH_A_NPS) ? " NPS" : "",
210 			(temp & RH_A_PSM) ? " PSM" : "",
211 			(temp & RH_A_NDP), controller->num_ports
212 			);
213 		temp = roothub_b (controller);
214 		ohci_dbg_sw (controller, next, size,
215 			"roothub.b %08x PPCM=%04x DR=%04x\n",
216 			temp,
217 			(temp & RH_B_PPCM) >> 16,
218 			(temp & RH_B_DR)
219 			);
220 		temp = roothub_status (controller);
221 		ohci_dbg_sw (controller, next, size,
222 			"roothub.status %08x%s%s%s%s%s%s\n",
223 			temp,
224 			(temp & RH_HS_CRWE) ? " CRWE" : "",
225 			(temp & RH_HS_OCIC) ? " OCIC" : "",
226 			(temp & RH_HS_LPSC) ? " LPSC" : "",
227 			(temp & RH_HS_DRWE) ? " DRWE" : "",
228 			(temp & RH_HS_OCI) ? " OCI" : "",
229 			(temp & RH_HS_LPS) ? " LPS" : ""
230 			);
231 	}
232 
233 	for (i = 0; i < controller->num_ports; i++) {
234 		temp = roothub_portstatus (controller, i);
235 		dbg_port_sw (controller, i, temp, next, size);
236 	}
237 }
238 
239 static void ohci_dump(struct ohci_hcd *controller)
240 {
241 	ohci_dbg (controller, "OHCI controller state\n");
242 
243 	// dumps some of the state we know about
244 	ohci_dump_status (controller, NULL, NULL);
245 	if (controller->hcca)
246 		ohci_dbg (controller,
247 			"hcca frame #%04x\n", ohci_frame_no(controller));
248 	ohci_dump_roothub (controller, 1, NULL, NULL);
249 }
250 
251 static const char data0 [] = "DATA0";
252 static const char data1 [] = "DATA1";
253 
254 static void ohci_dump_td (const struct ohci_hcd *ohci, const char *label,
255 		const struct td *td)
256 {
257 	u32	tmp = hc32_to_cpup (ohci, &td->hwINFO);
258 
259 	ohci_dbg (ohci, "%s td %p%s; urb %p index %d; hw next td %08x\n",
260 		label, td,
261 		(tmp & TD_DONE) ? " (DONE)" : "",
262 		td->urb, td->index,
263 		hc32_to_cpup (ohci, &td->hwNextTD));
264 	if ((tmp & TD_ISO) == 0) {
265 		const char	*toggle, *pid;
266 		u32	cbp, be;
267 
268 		switch (tmp & TD_T) {
269 		case TD_T_DATA0: toggle = data0; break;
270 		case TD_T_DATA1: toggle = data1; break;
271 		case TD_T_TOGGLE: toggle = "(CARRY)"; break;
272 		default: toggle = "(?)"; break;
273 		}
274 		switch (tmp & TD_DP) {
275 		case TD_DP_SETUP: pid = "SETUP"; break;
276 		case TD_DP_IN: pid = "IN"; break;
277 		case TD_DP_OUT: pid = "OUT"; break;
278 		default: pid = "(bad pid)"; break;
279 		}
280 		ohci_dbg (ohci, "     info %08x CC=%x %s DI=%d %s %s\n", tmp,
281 			TD_CC_GET(tmp), /* EC, */ toggle,
282 			(tmp & TD_DI) >> 21, pid,
283 			(tmp & TD_R) ? "R" : "");
284 		cbp = hc32_to_cpup (ohci, &td->hwCBP);
285 		be = hc32_to_cpup (ohci, &td->hwBE);
286 		ohci_dbg (ohci, "     cbp %08x be %08x (len %d)\n", cbp, be,
287 			cbp ? (be + 1 - cbp) : 0);
288 	} else {
289 		unsigned	i;
290 		ohci_dbg (ohci, "  info %08x CC=%x FC=%d DI=%d SF=%04x\n", tmp,
291 			TD_CC_GET(tmp),
292 			(tmp >> 24) & 0x07,
293 			(tmp & TD_DI) >> 21,
294 			tmp & 0x0000ffff);
295 		ohci_dbg (ohci, "  bp0 %08x be %08x\n",
296 			hc32_to_cpup (ohci, &td->hwCBP) & ~0x0fff,
297 			hc32_to_cpup (ohci, &td->hwBE));
298 		for (i = 0; i < MAXPSW; i++) {
299 			u16	psw = ohci_hwPSW (ohci, td, i);
300 			int	cc = (psw >> 12) & 0x0f;
301 			ohci_dbg (ohci, "    psw [%d] = %2x, CC=%x %s=%d\n", i,
302 				psw, cc,
303 				(cc >= 0x0e) ? "OFFSET" : "SIZE",
304 				psw & 0x0fff);
305 		}
306 	}
307 }
308 
309 /* caller MUST own hcd spinlock if verbose is set! */
310 static void __maybe_unused
311 ohci_dump_ed (const struct ohci_hcd *ohci, const char *label,
312 		const struct ed *ed, int verbose)
313 {
314 	u32	tmp = hc32_to_cpu (ohci, ed->hwINFO);
315 	char	*type = "";
316 
317 	ohci_dbg (ohci, "%s, ed %p state 0x%x type %s; next ed %08x\n",
318 		label,
319 		ed, ed->state, edstring (ed->type),
320 		hc32_to_cpup (ohci, &ed->hwNextED));
321 	switch (tmp & (ED_IN|ED_OUT)) {
322 	case ED_OUT: type = "-OUT"; break;
323 	case ED_IN: type = "-IN"; break;
324 	/* else from TDs ... control */
325 	}
326 	ohci_dbg (ohci,
327 		"  info %08x MAX=%d%s%s%s%s EP=%d%s DEV=%d\n", tmp,
328 		0x03ff & (tmp >> 16),
329 		(tmp & ED_DEQUEUE) ? " DQ" : "",
330 		(tmp & ED_ISO) ? " ISO" : "",
331 		(tmp & ED_SKIP) ? " SKIP" : "",
332 		(tmp & ED_LOWSPEED) ? " LOW" : "",
333 		0x000f & (tmp >> 7),
334 		type,
335 		0x007f & tmp);
336 	tmp = hc32_to_cpup (ohci, &ed->hwHeadP);
337 	ohci_dbg (ohci, "  tds: head %08x %s%s tail %08x%s\n",
338 		tmp,
339 		(tmp & ED_C) ? data1 : data0,
340 		(tmp & ED_H) ? " HALT" : "",
341 		hc32_to_cpup (ohci, &ed->hwTailP),
342 		verbose ? "" : " (not listing)");
343 	if (verbose) {
344 		struct list_head	*tmp;
345 
346 		/* use ed->td_list because HC concurrently modifies
347 		 * hwNextTD as it accumulates ed_donelist.
348 		 */
349 		list_for_each (tmp, &ed->td_list) {
350 			struct td		*td;
351 			td = list_entry (tmp, struct td, td_list);
352 			ohci_dump_td (ohci, "  ->", td);
353 		}
354 	}
355 }
356 
357 /*-------------------------------------------------------------------------*/
358 
359 static int debug_async_open(struct inode *, struct file *);
360 static int debug_periodic_open(struct inode *, struct file *);
361 static int debug_registers_open(struct inode *, struct file *);
362 static int debug_async_open(struct inode *, struct file *);
363 static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
364 static int debug_close(struct inode *, struct file *);
365 
366 static const struct file_operations debug_async_fops = {
367 	.owner		= THIS_MODULE,
368 	.open		= debug_async_open,
369 	.read		= debug_output,
370 	.release	= debug_close,
371 	.llseek		= default_llseek,
372 };
373 static const struct file_operations debug_periodic_fops = {
374 	.owner		= THIS_MODULE,
375 	.open		= debug_periodic_open,
376 	.read		= debug_output,
377 	.release	= debug_close,
378 	.llseek		= default_llseek,
379 };
380 static const struct file_operations debug_registers_fops = {
381 	.owner		= THIS_MODULE,
382 	.open		= debug_registers_open,
383 	.read		= debug_output,
384 	.release	= debug_close,
385 	.llseek		= default_llseek,
386 };
387 
388 static struct dentry *ohci_debug_root;
389 
390 struct debug_buffer {
391 	ssize_t (*fill_func)(struct debug_buffer *);	/* fill method */
392 	struct ohci_hcd *ohci;
393 	struct mutex mutex;	/* protect filling of buffer */
394 	size_t count;		/* number of characters filled into buffer */
395 	char *page;
396 };
397 
398 static ssize_t
399 show_list (struct ohci_hcd *ohci, char *buf, size_t count, struct ed *ed)
400 {
401 	unsigned		temp, size = count;
402 
403 	if (!ed)
404 		return 0;
405 
406 	/* print first --> last */
407 	while (ed->ed_prev)
408 		ed = ed->ed_prev;
409 
410 	/* dump a snapshot of the bulk or control schedule */
411 	while (ed) {
412 		u32		info = hc32_to_cpu (ohci, ed->hwINFO);
413 		u32		headp = hc32_to_cpu (ohci, ed->hwHeadP);
414 		struct list_head *entry;
415 		struct td	*td;
416 
417 		temp = scnprintf (buf, size,
418 			"ed/%p %cs dev%d ep%d%s max %d %08x%s%s %s",
419 			ed,
420 			(info & ED_LOWSPEED) ? 'l' : 'f',
421 			info & 0x7f,
422 			(info >> 7) & 0xf,
423 			(info & ED_IN) ? "in" : "out",
424 			0x03ff & (info >> 16),
425 			info,
426 			(info & ED_SKIP) ? " s" : "",
427 			(headp & ED_H) ? " H" : "",
428 			(headp & ED_C) ? data1 : data0);
429 		size -= temp;
430 		buf += temp;
431 
432 		list_for_each (entry, &ed->td_list) {
433 			u32		cbp, be;
434 
435 			td = list_entry (entry, struct td, td_list);
436 			info = hc32_to_cpup (ohci, &td->hwINFO);
437 			cbp = hc32_to_cpup (ohci, &td->hwCBP);
438 			be = hc32_to_cpup (ohci, &td->hwBE);
439 			temp = scnprintf (buf, size,
440 					"\n\ttd %p %s %d cc=%x urb %p (%08x)",
441 					td,
442 					({ char *pid;
443 					switch (info & TD_DP) {
444 					case TD_DP_SETUP: pid = "setup"; break;
445 					case TD_DP_IN: pid = "in"; break;
446 					case TD_DP_OUT: pid = "out"; break;
447 					default: pid = "(?)"; break;
448 					 } pid;}),
449 					cbp ? (be + 1 - cbp) : 0,
450 					TD_CC_GET (info), td->urb, info);
451 			size -= temp;
452 			buf += temp;
453 		}
454 
455 		temp = scnprintf (buf, size, "\n");
456 		size -= temp;
457 		buf += temp;
458 
459 		ed = ed->ed_next;
460 	}
461 	return count - size;
462 }
463 
464 static ssize_t fill_async_buffer(struct debug_buffer *buf)
465 {
466 	struct ohci_hcd		*ohci;
467 	size_t			temp, size;
468 	unsigned long		flags;
469 
470 	ohci = buf->ohci;
471 	size = PAGE_SIZE;
472 
473 	/* display control and bulk lists together, for simplicity */
474 	spin_lock_irqsave (&ohci->lock, flags);
475 	temp = show_list(ohci, buf->page, size, ohci->ed_controltail);
476 	temp += show_list(ohci, buf->page + temp, size - temp,
477 			  ohci->ed_bulktail);
478 	spin_unlock_irqrestore (&ohci->lock, flags);
479 
480 	return temp;
481 }
482 
483 #define DBG_SCHED_LIMIT 64
484 
485 static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
486 {
487 	struct ohci_hcd		*ohci;
488 	struct ed		**seen, *ed;
489 	unsigned long		flags;
490 	unsigned		temp, size, seen_count;
491 	char			*next;
492 	unsigned		i;
493 
494 	if (!(seen = kmalloc (DBG_SCHED_LIMIT * sizeof *seen, GFP_ATOMIC)))
495 		return 0;
496 	seen_count = 0;
497 
498 	ohci = buf->ohci;
499 	next = buf->page;
500 	size = PAGE_SIZE;
501 
502 	temp = scnprintf (next, size, "size = %d\n", NUM_INTS);
503 	size -= temp;
504 	next += temp;
505 
506 	/* dump a snapshot of the periodic schedule (and load) */
507 	spin_lock_irqsave (&ohci->lock, flags);
508 	for (i = 0; i < NUM_INTS; i++) {
509 		if (!(ed = ohci->periodic [i]))
510 			continue;
511 
512 		temp = scnprintf (next, size, "%2d [%3d]:", i, ohci->load [i]);
513 		size -= temp;
514 		next += temp;
515 
516 		do {
517 			temp = scnprintf (next, size, " ed%d/%p",
518 				ed->interval, ed);
519 			size -= temp;
520 			next += temp;
521 			for (temp = 0; temp < seen_count; temp++) {
522 				if (seen [temp] == ed)
523 					break;
524 			}
525 
526 			/* show more info the first time around */
527 			if (temp == seen_count) {
528 				u32	info = hc32_to_cpu (ohci, ed->hwINFO);
529 				struct list_head	*entry;
530 				unsigned		qlen = 0;
531 
532 				/* qlen measured here in TDs, not urbs */
533 				list_for_each (entry, &ed->td_list)
534 					qlen++;
535 
536 				temp = scnprintf (next, size,
537 					" (%cs dev%d ep%d%s-%s qlen %u"
538 					" max %d %08x%s%s)",
539 					(info & ED_LOWSPEED) ? 'l' : 'f',
540 					info & 0x7f,
541 					(info >> 7) & 0xf,
542 					(info & ED_IN) ? "in" : "out",
543 					(info & ED_ISO) ? "iso" : "int",
544 					qlen,
545 					0x03ff & (info >> 16),
546 					info,
547 					(info & ED_SKIP) ? " K" : "",
548 					(ed->hwHeadP &
549 						cpu_to_hc32(ohci, ED_H)) ?
550 							" H" : "");
551 				size -= temp;
552 				next += temp;
553 
554 				if (seen_count < DBG_SCHED_LIMIT)
555 					seen [seen_count++] = ed;
556 
557 				ed = ed->ed_next;
558 
559 			} else {
560 				/* we've seen it and what's after */
561 				temp = 0;
562 				ed = NULL;
563 			}
564 
565 		} while (ed);
566 
567 		temp = scnprintf (next, size, "\n");
568 		size -= temp;
569 		next += temp;
570 	}
571 	spin_unlock_irqrestore (&ohci->lock, flags);
572 	kfree (seen);
573 
574 	return PAGE_SIZE - size;
575 }
576 #undef DBG_SCHED_LIMIT
577 
578 static ssize_t fill_registers_buffer(struct debug_buffer *buf)
579 {
580 	struct usb_hcd		*hcd;
581 	struct ohci_hcd		*ohci;
582 	struct ohci_regs __iomem *regs;
583 	unsigned long		flags;
584 	unsigned		temp, size;
585 	char			*next;
586 	u32			rdata;
587 
588 	ohci = buf->ohci;
589 	hcd = ohci_to_hcd(ohci);
590 	regs = ohci->regs;
591 	next = buf->page;
592 	size = PAGE_SIZE;
593 
594 	spin_lock_irqsave (&ohci->lock, flags);
595 
596 	/* dump driver info, then registers in spec order */
597 
598 	ohci_dbg_nosw(ohci, &next, &size,
599 		"bus %s, device %s\n"
600 		"%s\n"
601 		"%s\n",
602 		hcd->self.controller->bus->name,
603 		dev_name(hcd->self.controller),
604 		hcd->product_desc,
605 		hcd_name);
606 
607 	if (!HCD_HW_ACCESSIBLE(hcd)) {
608 		size -= scnprintf (next, size,
609 			"SUSPENDED (no register access)\n");
610 		goto done;
611 	}
612 
613 	ohci_dump_status(ohci, &next, &size);
614 
615 	/* hcca */
616 	if (ohci->hcca)
617 		ohci_dbg_nosw(ohci, &next, &size,
618 			"hcca frame 0x%04x\n", ohci_frame_no(ohci));
619 
620 	/* other registers mostly affect frame timings */
621 	rdata = ohci_readl (ohci, &regs->fminterval);
622 	temp = scnprintf (next, size,
623 			"fmintvl 0x%08x %sFSMPS=0x%04x FI=0x%04x\n",
624 			rdata, (rdata >> 31) ? "FIT " : "",
625 			(rdata >> 16) & 0xefff, rdata & 0xffff);
626 	size -= temp;
627 	next += temp;
628 
629 	rdata = ohci_readl (ohci, &regs->fmremaining);
630 	temp = scnprintf (next, size, "fmremaining 0x%08x %sFR=0x%04x\n",
631 			rdata, (rdata >> 31) ? "FRT " : "",
632 			rdata & 0x3fff);
633 	size -= temp;
634 	next += temp;
635 
636 	rdata = ohci_readl (ohci, &regs->periodicstart);
637 	temp = scnprintf (next, size, "periodicstart 0x%04x\n",
638 			rdata & 0x3fff);
639 	size -= temp;
640 	next += temp;
641 
642 	rdata = ohci_readl (ohci, &regs->lsthresh);
643 	temp = scnprintf (next, size, "lsthresh 0x%04x\n",
644 			rdata & 0x3fff);
645 	size -= temp;
646 	next += temp;
647 
648 	temp = scnprintf (next, size, "hub poll timer %s\n",
649 			HCD_POLL_RH(ohci_to_hcd(ohci)) ? "ON" : "off");
650 	size -= temp;
651 	next += temp;
652 
653 	/* roothub */
654 	ohci_dump_roothub (ohci, 1, &next, &size);
655 
656 done:
657 	spin_unlock_irqrestore (&ohci->lock, flags);
658 
659 	return PAGE_SIZE - size;
660 }
661 
662 static struct debug_buffer *alloc_buffer(struct ohci_hcd *ohci,
663 				ssize_t (*fill_func)(struct debug_buffer *))
664 {
665 	struct debug_buffer *buf;
666 
667 	buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
668 
669 	if (buf) {
670 		buf->ohci = ohci;
671 		buf->fill_func = fill_func;
672 		mutex_init(&buf->mutex);
673 	}
674 
675 	return buf;
676 }
677 
678 static int fill_buffer(struct debug_buffer *buf)
679 {
680 	int ret = 0;
681 
682 	if (!buf->page)
683 		buf->page = (char *)get_zeroed_page(GFP_KERNEL);
684 
685 	if (!buf->page) {
686 		ret = -ENOMEM;
687 		goto out;
688 	}
689 
690 	ret = buf->fill_func(buf);
691 
692 	if (ret >= 0) {
693 		buf->count = ret;
694 		ret = 0;
695 	}
696 
697 out:
698 	return ret;
699 }
700 
701 static ssize_t debug_output(struct file *file, char __user *user_buf,
702 			size_t len, loff_t *offset)
703 {
704 	struct debug_buffer *buf = file->private_data;
705 	int ret = 0;
706 
707 	mutex_lock(&buf->mutex);
708 	if (buf->count == 0) {
709 		ret = fill_buffer(buf);
710 		if (ret != 0) {
711 			mutex_unlock(&buf->mutex);
712 			goto out;
713 		}
714 	}
715 	mutex_unlock(&buf->mutex);
716 
717 	ret = simple_read_from_buffer(user_buf, len, offset,
718 				      buf->page, buf->count);
719 
720 out:
721 	return ret;
722 
723 }
724 
725 static int debug_close(struct inode *inode, struct file *file)
726 {
727 	struct debug_buffer *buf = file->private_data;
728 
729 	if (buf) {
730 		if (buf->page)
731 			free_page((unsigned long)buf->page);
732 		kfree(buf);
733 	}
734 
735 	return 0;
736 }
737 static int debug_async_open(struct inode *inode, struct file *file)
738 {
739 	file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);
740 
741 	return file->private_data ? 0 : -ENOMEM;
742 }
743 
744 static int debug_periodic_open(struct inode *inode, struct file *file)
745 {
746 	file->private_data = alloc_buffer(inode->i_private,
747 					  fill_periodic_buffer);
748 
749 	return file->private_data ? 0 : -ENOMEM;
750 }
751 
752 static int debug_registers_open(struct inode *inode, struct file *file)
753 {
754 	file->private_data = alloc_buffer(inode->i_private,
755 					  fill_registers_buffer);
756 
757 	return file->private_data ? 0 : -ENOMEM;
758 }
759 static inline void create_debug_files (struct ohci_hcd *ohci)
760 {
761 	struct usb_bus *bus = &ohci_to_hcd(ohci)->self;
762 
763 	ohci->debug_dir = debugfs_create_dir(bus->bus_name, ohci_debug_root);
764 	if (!ohci->debug_dir)
765 		goto dir_error;
766 
767 	ohci->debug_async = debugfs_create_file("async", S_IRUGO,
768 						ohci->debug_dir, ohci,
769 						&debug_async_fops);
770 	if (!ohci->debug_async)
771 		goto async_error;
772 
773 	ohci->debug_periodic = debugfs_create_file("periodic", S_IRUGO,
774 						   ohci->debug_dir, ohci,
775 						   &debug_periodic_fops);
776 	if (!ohci->debug_periodic)
777 		goto periodic_error;
778 
779 	ohci->debug_registers = debugfs_create_file("registers", S_IRUGO,
780 						    ohci->debug_dir, ohci,
781 						    &debug_registers_fops);
782 	if (!ohci->debug_registers)
783 		goto registers_error;
784 
785 	ohci_dbg (ohci, "created debug files\n");
786 	return;
787 
788 registers_error:
789 	debugfs_remove(ohci->debug_periodic);
790 periodic_error:
791 	debugfs_remove(ohci->debug_async);
792 async_error:
793 	debugfs_remove(ohci->debug_dir);
794 dir_error:
795 	ohci->debug_periodic = NULL;
796 	ohci->debug_async = NULL;
797 	ohci->debug_dir = NULL;
798 }
799 
800 static inline void remove_debug_files (struct ohci_hcd *ohci)
801 {
802 	debugfs_remove(ohci->debug_registers);
803 	debugfs_remove(ohci->debug_periodic);
804 	debugfs_remove(ohci->debug_async);
805 	debugfs_remove(ohci->debug_dir);
806 }
807 
808 /*-------------------------------------------------------------------------*/
809 
810