xref: /openbmc/linux/drivers/usb/host/ohci-dbg.c (revision 6038f373)
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 #ifdef DEBUG
13 
14 #define edstring(ed_type) ({ char *temp; \
15 	switch (ed_type) { \
16 	case PIPE_CONTROL:	temp = "ctrl"; break; \
17 	case PIPE_BULK:		temp = "bulk"; break; \
18 	case PIPE_INTERRUPT:	temp = "intr"; break; \
19 	default:		temp = "isoc"; break; \
20 	}; temp;})
21 #define pipestring(pipe) edstring(usb_pipetype(pipe))
22 
23 /* debug| print the main components of an URB
24  * small: 0) header + data packets 1) just header
25  */
26 static void __maybe_unused
27 urb_print(struct urb * urb, char * str, int small, int status)
28 {
29 	unsigned int pipe= urb->pipe;
30 
31 	if (!urb->dev || !urb->dev->bus) {
32 		dbg("%s URB: no dev", str);
33 		return;
34 	}
35 
36 #ifndef	OHCI_VERBOSE_DEBUG
37 	if (status != 0)
38 #endif
39 	dbg("%s %p dev=%d ep=%d%s-%s flags=%x len=%d/%d stat=%d",
40 		    str,
41 		    urb,
42 		    usb_pipedevice (pipe),
43 		    usb_pipeendpoint (pipe),
44 		    usb_pipeout (pipe)? "out" : "in",
45 		    pipestring (pipe),
46 		    urb->transfer_flags,
47 		    urb->actual_length,
48 		    urb->transfer_buffer_length,
49 		    status);
50 
51 #ifdef	OHCI_VERBOSE_DEBUG
52 	if (!small) {
53 		int i, len;
54 
55 		if (usb_pipecontrol (pipe)) {
56 			printk (KERN_DEBUG "%s: setup(8):", __FILE__);
57 			for (i = 0; i < 8 ; i++)
58 				printk (" %02x", ((__u8 *) urb->setup_packet) [i]);
59 			printk ("\n");
60 		}
61 		if (urb->transfer_buffer_length > 0 && urb->transfer_buffer) {
62 			printk (KERN_DEBUG "%s: data(%d/%d):", __FILE__,
63 				urb->actual_length,
64 				urb->transfer_buffer_length);
65 			len = usb_pipeout (pipe)?
66 						urb->transfer_buffer_length: urb->actual_length;
67 			for (i = 0; i < 16 && i < len; i++)
68 				printk (" %02x", ((__u8 *) urb->transfer_buffer) [i]);
69 			printk ("%s stat:%d\n", i < len? "...": "", status);
70 		}
71 	}
72 #endif
73 }
74 
75 #define ohci_dbg_sw(ohci, next, size, format, arg...) \
76 	do { \
77 	if (next != NULL) { \
78 		unsigned s_len; \
79 		s_len = scnprintf (*next, *size, format, ## arg ); \
80 		*size -= s_len; *next += s_len; \
81 	} else \
82 		ohci_dbg(ohci,format, ## arg ); \
83 	} while (0);
84 
85 
86 static void ohci_dump_intr_mask (
87 	struct ohci_hcd *ohci,
88 	char *label,
89 	u32 mask,
90 	char **next,
91 	unsigned *size)
92 {
93 	ohci_dbg_sw (ohci, next, size, "%s 0x%08x%s%s%s%s%s%s%s%s%s\n",
94 		label,
95 		mask,
96 		(mask & OHCI_INTR_MIE) ? " MIE" : "",
97 		(mask & OHCI_INTR_OC) ? " OC" : "",
98 		(mask & OHCI_INTR_RHSC) ? " RHSC" : "",
99 		(mask & OHCI_INTR_FNO) ? " FNO" : "",
100 		(mask & OHCI_INTR_UE) ? " UE" : "",
101 		(mask & OHCI_INTR_RD) ? " RD" : "",
102 		(mask & OHCI_INTR_SF) ? " SF" : "",
103 		(mask & OHCI_INTR_WDH) ? " WDH" : "",
104 		(mask & OHCI_INTR_SO) ? " SO" : ""
105 		);
106 }
107 
108 static void maybe_print_eds (
109 	struct ohci_hcd *ohci,
110 	char *label,
111 	u32 value,
112 	char **next,
113 	unsigned *size)
114 {
115 	if (value)
116 		ohci_dbg_sw (ohci, next, size, "%s %08x\n", label, value);
117 }
118 
119 static char *hcfs2string (int state)
120 {
121 	switch (state) {
122 		case OHCI_USB_RESET:	return "reset";
123 		case OHCI_USB_RESUME:	return "resume";
124 		case OHCI_USB_OPER:	return "operational";
125 		case OHCI_USB_SUSPEND:	return "suspend";
126 	}
127 	return "?";
128 }
129 
130 // dump control and status registers
131 static void
132 ohci_dump_status (struct ohci_hcd *controller, char **next, unsigned *size)
133 {
134 	struct ohci_regs __iomem *regs = controller->regs;
135 	u32			temp;
136 
137 	temp = ohci_readl (controller, &regs->revision) & 0xff;
138 	ohci_dbg_sw (controller, next, size,
139 		"OHCI %d.%d, %s legacy support registers\n",
140 		0x03 & (temp >> 4), (temp & 0x0f),
141 		(temp & 0x0100) ? "with" : "NO");
142 
143 	temp = ohci_readl (controller, &regs->control);
144 	ohci_dbg_sw (controller, next, size,
145 		"control 0x%03x%s%s%s HCFS=%s%s%s%s%s CBSR=%d\n",
146 		temp,
147 		(temp & OHCI_CTRL_RWE) ? " RWE" : "",
148 		(temp & OHCI_CTRL_RWC) ? " RWC" : "",
149 		(temp & OHCI_CTRL_IR) ? " IR" : "",
150 		hcfs2string (temp & OHCI_CTRL_HCFS),
151 		(temp & OHCI_CTRL_BLE) ? " BLE" : "",
152 		(temp & OHCI_CTRL_CLE) ? " CLE" : "",
153 		(temp & OHCI_CTRL_IE) ? " IE" : "",
154 		(temp & OHCI_CTRL_PLE) ? " PLE" : "",
155 		temp & OHCI_CTRL_CBSR
156 		);
157 
158 	temp = ohci_readl (controller, &regs->cmdstatus);
159 	ohci_dbg_sw (controller, next, size,
160 		"cmdstatus 0x%05x SOC=%d%s%s%s%s\n", temp,
161 		(temp & OHCI_SOC) >> 16,
162 		(temp & OHCI_OCR) ? " OCR" : "",
163 		(temp & OHCI_BLF) ? " BLF" : "",
164 		(temp & OHCI_CLF) ? " CLF" : "",
165 		(temp & OHCI_HCR) ? " HCR" : ""
166 		);
167 
168 	ohci_dump_intr_mask (controller, "intrstatus",
169 			ohci_readl (controller, &regs->intrstatus),
170 			next, size);
171 	ohci_dump_intr_mask (controller, "intrenable",
172 			ohci_readl (controller, &regs->intrenable),
173 			next, size);
174 	// intrdisable always same as intrenable
175 
176 	maybe_print_eds (controller, "ed_periodcurrent",
177 			ohci_readl (controller, &regs->ed_periodcurrent),
178 			next, size);
179 
180 	maybe_print_eds (controller, "ed_controlhead",
181 			ohci_readl (controller, &regs->ed_controlhead),
182 			next, size);
183 	maybe_print_eds (controller, "ed_controlcurrent",
184 			ohci_readl (controller, &regs->ed_controlcurrent),
185 			next, size);
186 
187 	maybe_print_eds (controller, "ed_bulkhead",
188 			ohci_readl (controller, &regs->ed_bulkhead),
189 			next, size);
190 	maybe_print_eds (controller, "ed_bulkcurrent",
191 			ohci_readl (controller, &regs->ed_bulkcurrent),
192 			next, size);
193 
194 	maybe_print_eds (controller, "donehead",
195 			ohci_readl (controller, &regs->donehead), next, size);
196 }
197 
198 #define dbg_port_sw(hc,num,value,next,size) \
199 	ohci_dbg_sw (hc, next, size, \
200 		"roothub.portstatus [%d] " \
201 		"0x%08x%s%s%s%s%s%s%s%s%s%s%s%s\n", \
202 		num, temp, \
203 		(temp & RH_PS_PRSC) ? " PRSC" : "", \
204 		(temp & RH_PS_OCIC) ? " OCIC" : "", \
205 		(temp & RH_PS_PSSC) ? " PSSC" : "", \
206 		(temp & RH_PS_PESC) ? " PESC" : "", \
207 		(temp & RH_PS_CSC) ? " CSC" : "", \
208 		\
209 		(temp & RH_PS_LSDA) ? " LSDA" : "", \
210 		(temp & RH_PS_PPS) ? " PPS" : "", \
211 		(temp & RH_PS_PRS) ? " PRS" : "", \
212 		(temp & RH_PS_POCI) ? " POCI" : "", \
213 		(temp & RH_PS_PSS) ? " PSS" : "", \
214 		\
215 		(temp & RH_PS_PES) ? " PES" : "", \
216 		(temp & RH_PS_CCS) ? " CCS" : "" \
217 		);
218 
219 
220 static void
221 ohci_dump_roothub (
222 	struct ohci_hcd *controller,
223 	int verbose,
224 	char **next,
225 	unsigned *size)
226 {
227 	u32			temp, i;
228 
229 	temp = roothub_a (controller);
230 	if (temp == ~(u32)0)
231 		return;
232 
233 	if (verbose) {
234 		ohci_dbg_sw (controller, next, size,
235 			"roothub.a %08x POTPGT=%d%s%s%s%s%s NDP=%d(%d)\n", temp,
236 			((temp & RH_A_POTPGT) >> 24) & 0xff,
237 			(temp & RH_A_NOCP) ? " NOCP" : "",
238 			(temp & RH_A_OCPM) ? " OCPM" : "",
239 			(temp & RH_A_DT) ? " DT" : "",
240 			(temp & RH_A_NPS) ? " NPS" : "",
241 			(temp & RH_A_PSM) ? " PSM" : "",
242 			(temp & RH_A_NDP), controller->num_ports
243 			);
244 		temp = roothub_b (controller);
245 		ohci_dbg_sw (controller, next, size,
246 			"roothub.b %08x PPCM=%04x DR=%04x\n",
247 			temp,
248 			(temp & RH_B_PPCM) >> 16,
249 			(temp & RH_B_DR)
250 			);
251 		temp = roothub_status (controller);
252 		ohci_dbg_sw (controller, next, size,
253 			"roothub.status %08x%s%s%s%s%s%s\n",
254 			temp,
255 			(temp & RH_HS_CRWE) ? " CRWE" : "",
256 			(temp & RH_HS_OCIC) ? " OCIC" : "",
257 			(temp & RH_HS_LPSC) ? " LPSC" : "",
258 			(temp & RH_HS_DRWE) ? " DRWE" : "",
259 			(temp & RH_HS_OCI) ? " OCI" : "",
260 			(temp & RH_HS_LPS) ? " LPS" : ""
261 			);
262 	}
263 
264 	for (i = 0; i < controller->num_ports; i++) {
265 		temp = roothub_portstatus (controller, i);
266 		dbg_port_sw (controller, i, temp, next, size);
267 	}
268 }
269 
270 static void ohci_dump (struct ohci_hcd *controller, int verbose)
271 {
272 	ohci_dbg (controller, "OHCI controller state\n");
273 
274 	// dumps some of the state we know about
275 	ohci_dump_status (controller, NULL, NULL);
276 	if (controller->hcca)
277 		ohci_dbg (controller,
278 			"hcca frame #%04x\n", ohci_frame_no(controller));
279 	ohci_dump_roothub (controller, 1, NULL, NULL);
280 }
281 
282 static const char data0 [] = "DATA0";
283 static const char data1 [] = "DATA1";
284 
285 static void ohci_dump_td (const struct ohci_hcd *ohci, const char *label,
286 		const struct td *td)
287 {
288 	u32	tmp = hc32_to_cpup (ohci, &td->hwINFO);
289 
290 	ohci_dbg (ohci, "%s td %p%s; urb %p index %d; hw next td %08x\n",
291 		label, td,
292 		(tmp & TD_DONE) ? " (DONE)" : "",
293 		td->urb, td->index,
294 		hc32_to_cpup (ohci, &td->hwNextTD));
295 	if ((tmp & TD_ISO) == 0) {
296 		const char	*toggle, *pid;
297 		u32	cbp, be;
298 
299 		switch (tmp & TD_T) {
300 		case TD_T_DATA0: toggle = data0; break;
301 		case TD_T_DATA1: toggle = data1; break;
302 		case TD_T_TOGGLE: toggle = "(CARRY)"; break;
303 		default: toggle = "(?)"; break;
304 		}
305 		switch (tmp & TD_DP) {
306 		case TD_DP_SETUP: pid = "SETUP"; break;
307 		case TD_DP_IN: pid = "IN"; break;
308 		case TD_DP_OUT: pid = "OUT"; break;
309 		default: pid = "(bad pid)"; break;
310 		}
311 		ohci_dbg (ohci, "     info %08x CC=%x %s DI=%d %s %s\n", tmp,
312 			TD_CC_GET(tmp), /* EC, */ toggle,
313 			(tmp & TD_DI) >> 21, pid,
314 			(tmp & TD_R) ? "R" : "");
315 		cbp = hc32_to_cpup (ohci, &td->hwCBP);
316 		be = hc32_to_cpup (ohci, &td->hwBE);
317 		ohci_dbg (ohci, "     cbp %08x be %08x (len %d)\n", cbp, be,
318 			cbp ? (be + 1 - cbp) : 0);
319 	} else {
320 		unsigned	i;
321 		ohci_dbg (ohci, "  info %08x CC=%x FC=%d DI=%d SF=%04x\n", tmp,
322 			TD_CC_GET(tmp),
323 			(tmp >> 24) & 0x07,
324 			(tmp & TD_DI) >> 21,
325 			tmp & 0x0000ffff);
326 		ohci_dbg (ohci, "  bp0 %08x be %08x\n",
327 			hc32_to_cpup (ohci, &td->hwCBP) & ~0x0fff,
328 			hc32_to_cpup (ohci, &td->hwBE));
329 		for (i = 0; i < MAXPSW; i++) {
330 			u16	psw = ohci_hwPSW (ohci, td, i);
331 			int	cc = (psw >> 12) & 0x0f;
332 			ohci_dbg (ohci, "    psw [%d] = %2x, CC=%x %s=%d\n", i,
333 				psw, cc,
334 				(cc >= 0x0e) ? "OFFSET" : "SIZE",
335 				psw & 0x0fff);
336 		}
337 	}
338 }
339 
340 /* caller MUST own hcd spinlock if verbose is set! */
341 static void __maybe_unused
342 ohci_dump_ed (const struct ohci_hcd *ohci, const char *label,
343 		const struct ed *ed, int verbose)
344 {
345 	u32	tmp = hc32_to_cpu (ohci, ed->hwINFO);
346 	char	*type = "";
347 
348 	ohci_dbg (ohci, "%s, ed %p state 0x%x type %s; next ed %08x\n",
349 		label,
350 		ed, ed->state, edstring (ed->type),
351 		hc32_to_cpup (ohci, &ed->hwNextED));
352 	switch (tmp & (ED_IN|ED_OUT)) {
353 	case ED_OUT: type = "-OUT"; break;
354 	case ED_IN: type = "-IN"; break;
355 	/* else from TDs ... control */
356 	}
357 	ohci_dbg (ohci,
358 		"  info %08x MAX=%d%s%s%s%s EP=%d%s DEV=%d\n", tmp,
359 		0x03ff & (tmp >> 16),
360 		(tmp & ED_DEQUEUE) ? " DQ" : "",
361 		(tmp & ED_ISO) ? " ISO" : "",
362 		(tmp & ED_SKIP) ? " SKIP" : "",
363 		(tmp & ED_LOWSPEED) ? " LOW" : "",
364 		0x000f & (tmp >> 7),
365 		type,
366 		0x007f & tmp);
367 	tmp = hc32_to_cpup (ohci, &ed->hwHeadP);
368 	ohci_dbg (ohci, "  tds: head %08x %s%s tail %08x%s\n",
369 		tmp,
370 		(tmp & ED_C) ? data1 : data0,
371 		(tmp & ED_H) ? " HALT" : "",
372 		hc32_to_cpup (ohci, &ed->hwTailP),
373 		verbose ? "" : " (not listing)");
374 	if (verbose) {
375 		struct list_head	*tmp;
376 
377 		/* use ed->td_list because HC concurrently modifies
378 		 * hwNextTD as it accumulates ed_donelist.
379 		 */
380 		list_for_each (tmp, &ed->td_list) {
381 			struct td		*td;
382 			td = list_entry (tmp, struct td, td_list);
383 			ohci_dump_td (ohci, "  ->", td);
384 		}
385 	}
386 }
387 
388 #else
389 static inline void ohci_dump (struct ohci_hcd *controller, int verbose) {}
390 
391 #undef OHCI_VERBOSE_DEBUG
392 
393 #endif /* DEBUG */
394 
395 /*-------------------------------------------------------------------------*/
396 
397 #ifdef STUB_DEBUG_FILES
398 
399 static inline void create_debug_files (struct ohci_hcd *bus) { }
400 static inline void remove_debug_files (struct ohci_hcd *bus) { }
401 
402 #else
403 
404 static int debug_async_open(struct inode *, struct file *);
405 static int debug_periodic_open(struct inode *, struct file *);
406 static int debug_registers_open(struct inode *, struct file *);
407 static int debug_async_open(struct inode *, struct file *);
408 static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
409 static int debug_close(struct inode *, struct file *);
410 
411 static const struct file_operations debug_async_fops = {
412 	.owner		= THIS_MODULE,
413 	.open		= debug_async_open,
414 	.read		= debug_output,
415 	.release	= debug_close,
416 	.llseek		= default_llseek,
417 };
418 static const struct file_operations debug_periodic_fops = {
419 	.owner		= THIS_MODULE,
420 	.open		= debug_periodic_open,
421 	.read		= debug_output,
422 	.release	= debug_close,
423 	.llseek		= default_llseek,
424 };
425 static const struct file_operations debug_registers_fops = {
426 	.owner		= THIS_MODULE,
427 	.open		= debug_registers_open,
428 	.read		= debug_output,
429 	.release	= debug_close,
430 	.llseek		= default_llseek,
431 };
432 
433 static struct dentry *ohci_debug_root;
434 
435 struct debug_buffer {
436 	ssize_t (*fill_func)(struct debug_buffer *);	/* fill method */
437 	struct ohci_hcd *ohci;
438 	struct mutex mutex;	/* protect filling of buffer */
439 	size_t count;		/* number of characters filled into buffer */
440 	char *page;
441 };
442 
443 static ssize_t
444 show_list (struct ohci_hcd *ohci, char *buf, size_t count, struct ed *ed)
445 {
446 	unsigned		temp, size = count;
447 
448 	if (!ed)
449 		return 0;
450 
451 	/* print first --> last */
452 	while (ed->ed_prev)
453 		ed = ed->ed_prev;
454 
455 	/* dump a snapshot of the bulk or control schedule */
456 	while (ed) {
457 		u32		info = hc32_to_cpu (ohci, ed->hwINFO);
458 		u32		headp = hc32_to_cpu (ohci, ed->hwHeadP);
459 		struct list_head *entry;
460 		struct td	*td;
461 
462 		temp = scnprintf (buf, size,
463 			"ed/%p %cs dev%d ep%d%s max %d %08x%s%s %s",
464 			ed,
465 			(info & ED_LOWSPEED) ? 'l' : 'f',
466 			info & 0x7f,
467 			(info >> 7) & 0xf,
468 			(info & ED_IN) ? "in" : "out",
469 			0x03ff & (info >> 16),
470 			info,
471 			(info & ED_SKIP) ? " s" : "",
472 			(headp & ED_H) ? " H" : "",
473 			(headp & ED_C) ? data1 : data0);
474 		size -= temp;
475 		buf += temp;
476 
477 		list_for_each (entry, &ed->td_list) {
478 			u32		cbp, be;
479 
480 			td = list_entry (entry, struct td, td_list);
481 			info = hc32_to_cpup (ohci, &td->hwINFO);
482 			cbp = hc32_to_cpup (ohci, &td->hwCBP);
483 			be = hc32_to_cpup (ohci, &td->hwBE);
484 			temp = scnprintf (buf, size,
485 					"\n\ttd %p %s %d cc=%x urb %p (%08x)",
486 					td,
487 					({ char *pid;
488 					switch (info & TD_DP) {
489 					case TD_DP_SETUP: pid = "setup"; break;
490 					case TD_DP_IN: pid = "in"; break;
491 					case TD_DP_OUT: pid = "out"; break;
492 					default: pid = "(?)"; break;
493 					 } pid;}),
494 					cbp ? (be + 1 - cbp) : 0,
495 					TD_CC_GET (info), td->urb, info);
496 			size -= temp;
497 			buf += temp;
498 		}
499 
500 		temp = scnprintf (buf, size, "\n");
501 		size -= temp;
502 		buf += temp;
503 
504 		ed = ed->ed_next;
505 	}
506 	return count - size;
507 }
508 
509 static ssize_t fill_async_buffer(struct debug_buffer *buf)
510 {
511 	struct ohci_hcd		*ohci;
512 	size_t			temp;
513 	unsigned long		flags;
514 
515 	ohci = buf->ohci;
516 
517 	/* display control and bulk lists together, for simplicity */
518 	spin_lock_irqsave (&ohci->lock, flags);
519 	temp = show_list(ohci, buf->page, buf->count, ohci->ed_controltail);
520 	temp += show_list(ohci, buf->page + temp, buf->count - temp,
521 			  ohci->ed_bulktail);
522 	spin_unlock_irqrestore (&ohci->lock, flags);
523 
524 	return temp;
525 }
526 
527 #define DBG_SCHED_LIMIT 64
528 
529 static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
530 {
531 	struct ohci_hcd		*ohci;
532 	struct ed		**seen, *ed;
533 	unsigned long		flags;
534 	unsigned		temp, size, seen_count;
535 	char			*next;
536 	unsigned		i;
537 
538 	if (!(seen = kmalloc (DBG_SCHED_LIMIT * sizeof *seen, GFP_ATOMIC)))
539 		return 0;
540 	seen_count = 0;
541 
542 	ohci = buf->ohci;
543 	next = buf->page;
544 	size = PAGE_SIZE;
545 
546 	temp = scnprintf (next, size, "size = %d\n", NUM_INTS);
547 	size -= temp;
548 	next += temp;
549 
550 	/* dump a snapshot of the periodic schedule (and load) */
551 	spin_lock_irqsave (&ohci->lock, flags);
552 	for (i = 0; i < NUM_INTS; i++) {
553 		if (!(ed = ohci->periodic [i]))
554 			continue;
555 
556 		temp = scnprintf (next, size, "%2d [%3d]:", i, ohci->load [i]);
557 		size -= temp;
558 		next += temp;
559 
560 		do {
561 			temp = scnprintf (next, size, " ed%d/%p",
562 				ed->interval, ed);
563 			size -= temp;
564 			next += temp;
565 			for (temp = 0; temp < seen_count; temp++) {
566 				if (seen [temp] == ed)
567 					break;
568 			}
569 
570 			/* show more info the first time around */
571 			if (temp == seen_count) {
572 				u32	info = hc32_to_cpu (ohci, ed->hwINFO);
573 				struct list_head	*entry;
574 				unsigned		qlen = 0;
575 
576 				/* qlen measured here in TDs, not urbs */
577 				list_for_each (entry, &ed->td_list)
578 					qlen++;
579 
580 				temp = scnprintf (next, size,
581 					" (%cs dev%d ep%d%s-%s qlen %u"
582 					" max %d %08x%s%s)",
583 					(info & ED_LOWSPEED) ? 'l' : 'f',
584 					info & 0x7f,
585 					(info >> 7) & 0xf,
586 					(info & ED_IN) ? "in" : "out",
587 					(info & ED_ISO) ? "iso" : "int",
588 					qlen,
589 					0x03ff & (info >> 16),
590 					info,
591 					(info & ED_SKIP) ? " K" : "",
592 					(ed->hwHeadP &
593 						cpu_to_hc32(ohci, ED_H)) ?
594 							" H" : "");
595 				size -= temp;
596 				next += temp;
597 
598 				if (seen_count < DBG_SCHED_LIMIT)
599 					seen [seen_count++] = ed;
600 
601 				ed = ed->ed_next;
602 
603 			} else {
604 				/* we've seen it and what's after */
605 				temp = 0;
606 				ed = NULL;
607 			}
608 
609 		} while (ed);
610 
611 		temp = scnprintf (next, size, "\n");
612 		size -= temp;
613 		next += temp;
614 	}
615 	spin_unlock_irqrestore (&ohci->lock, flags);
616 	kfree (seen);
617 
618 	return PAGE_SIZE - size;
619 }
620 #undef DBG_SCHED_LIMIT
621 
622 static ssize_t fill_registers_buffer(struct debug_buffer *buf)
623 {
624 	struct usb_hcd		*hcd;
625 	struct ohci_hcd		*ohci;
626 	struct ohci_regs __iomem *regs;
627 	unsigned long		flags;
628 	unsigned		temp, size;
629 	char			*next;
630 	u32			rdata;
631 
632 	ohci = buf->ohci;
633 	hcd = ohci_to_hcd(ohci);
634 	regs = ohci->regs;
635 	next = buf->page;
636 	size = PAGE_SIZE;
637 
638 	spin_lock_irqsave (&ohci->lock, flags);
639 
640 	/* dump driver info, then registers in spec order */
641 
642 	ohci_dbg_sw (ohci, &next, &size,
643 		"bus %s, device %s\n"
644 		"%s\n"
645 		"%s\n",
646 		hcd->self.controller->bus->name,
647 		dev_name(hcd->self.controller),
648 		hcd->product_desc,
649 		hcd_name);
650 
651 	if (!HCD_HW_ACCESSIBLE(hcd)) {
652 		size -= scnprintf (next, size,
653 			"SUSPENDED (no register access)\n");
654 		goto done;
655 	}
656 
657 	ohci_dump_status(ohci, &next, &size);
658 
659 	/* hcca */
660 	if (ohci->hcca)
661 		ohci_dbg_sw (ohci, &next, &size,
662 			"hcca frame 0x%04x\n", ohci_frame_no(ohci));
663 
664 	/* other registers mostly affect frame timings */
665 	rdata = ohci_readl (ohci, &regs->fminterval);
666 	temp = scnprintf (next, size,
667 			"fmintvl 0x%08x %sFSMPS=0x%04x FI=0x%04x\n",
668 			rdata, (rdata >> 31) ? "FIT " : "",
669 			(rdata >> 16) & 0xefff, rdata & 0xffff);
670 	size -= temp;
671 	next += temp;
672 
673 	rdata = ohci_readl (ohci, &regs->fmremaining);
674 	temp = scnprintf (next, size, "fmremaining 0x%08x %sFR=0x%04x\n",
675 			rdata, (rdata >> 31) ? "FRT " : "",
676 			rdata & 0x3fff);
677 	size -= temp;
678 	next += temp;
679 
680 	rdata = ohci_readl (ohci, &regs->periodicstart);
681 	temp = scnprintf (next, size, "periodicstart 0x%04x\n",
682 			rdata & 0x3fff);
683 	size -= temp;
684 	next += temp;
685 
686 	rdata = ohci_readl (ohci, &regs->lsthresh);
687 	temp = scnprintf (next, size, "lsthresh 0x%04x\n",
688 			rdata & 0x3fff);
689 	size -= temp;
690 	next += temp;
691 
692 	temp = scnprintf (next, size, "hub poll timer %s\n",
693 			HCD_POLL_RH(ohci_to_hcd(ohci)) ? "ON" : "off");
694 	size -= temp;
695 	next += temp;
696 
697 	/* roothub */
698 	ohci_dump_roothub (ohci, 1, &next, &size);
699 
700 done:
701 	spin_unlock_irqrestore (&ohci->lock, flags);
702 
703 	return PAGE_SIZE - size;
704 }
705 
706 static struct debug_buffer *alloc_buffer(struct ohci_hcd *ohci,
707 				ssize_t (*fill_func)(struct debug_buffer *))
708 {
709 	struct debug_buffer *buf;
710 
711 	buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
712 
713 	if (buf) {
714 		buf->ohci = ohci;
715 		buf->fill_func = fill_func;
716 		mutex_init(&buf->mutex);
717 	}
718 
719 	return buf;
720 }
721 
722 static int fill_buffer(struct debug_buffer *buf)
723 {
724 	int ret = 0;
725 
726 	if (!buf->page)
727 		buf->page = (char *)get_zeroed_page(GFP_KERNEL);
728 
729 	if (!buf->page) {
730 		ret = -ENOMEM;
731 		goto out;
732 	}
733 
734 	ret = buf->fill_func(buf);
735 
736 	if (ret >= 0) {
737 		buf->count = ret;
738 		ret = 0;
739 	}
740 
741 out:
742 	return ret;
743 }
744 
745 static ssize_t debug_output(struct file *file, char __user *user_buf,
746 			size_t len, loff_t *offset)
747 {
748 	struct debug_buffer *buf = file->private_data;
749 	int ret = 0;
750 
751 	mutex_lock(&buf->mutex);
752 	if (buf->count == 0) {
753 		ret = fill_buffer(buf);
754 		if (ret != 0) {
755 			mutex_unlock(&buf->mutex);
756 			goto out;
757 		}
758 	}
759 	mutex_unlock(&buf->mutex);
760 
761 	ret = simple_read_from_buffer(user_buf, len, offset,
762 				      buf->page, buf->count);
763 
764 out:
765 	return ret;
766 
767 }
768 
769 static int debug_close(struct inode *inode, struct file *file)
770 {
771 	struct debug_buffer *buf = file->private_data;
772 
773 	if (buf) {
774 		if (buf->page)
775 			free_page((unsigned long)buf->page);
776 		kfree(buf);
777 	}
778 
779 	return 0;
780 }
781 static int debug_async_open(struct inode *inode, struct file *file)
782 {
783 	file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);
784 
785 	return file->private_data ? 0 : -ENOMEM;
786 }
787 
788 static int debug_periodic_open(struct inode *inode, struct file *file)
789 {
790 	file->private_data = alloc_buffer(inode->i_private,
791 					  fill_periodic_buffer);
792 
793 	return file->private_data ? 0 : -ENOMEM;
794 }
795 
796 static int debug_registers_open(struct inode *inode, struct file *file)
797 {
798 	file->private_data = alloc_buffer(inode->i_private,
799 					  fill_registers_buffer);
800 
801 	return file->private_data ? 0 : -ENOMEM;
802 }
803 static inline void create_debug_files (struct ohci_hcd *ohci)
804 {
805 	struct usb_bus *bus = &ohci_to_hcd(ohci)->self;
806 
807 	ohci->debug_dir = debugfs_create_dir(bus->bus_name, ohci_debug_root);
808 	if (!ohci->debug_dir)
809 		goto dir_error;
810 
811 	ohci->debug_async = debugfs_create_file("async", S_IRUGO,
812 						ohci->debug_dir, ohci,
813 						&debug_async_fops);
814 	if (!ohci->debug_async)
815 		goto async_error;
816 
817 	ohci->debug_periodic = debugfs_create_file("periodic", S_IRUGO,
818 						   ohci->debug_dir, ohci,
819 						   &debug_periodic_fops);
820 	if (!ohci->debug_periodic)
821 		goto periodic_error;
822 
823 	ohci->debug_registers = debugfs_create_file("registers", S_IRUGO,
824 						    ohci->debug_dir, ohci,
825 						    &debug_registers_fops);
826 	if (!ohci->debug_registers)
827 		goto registers_error;
828 
829 	ohci_dbg (ohci, "created debug files\n");
830 	return;
831 
832 registers_error:
833 	debugfs_remove(ohci->debug_periodic);
834 periodic_error:
835 	debugfs_remove(ohci->debug_async);
836 async_error:
837 	debugfs_remove(ohci->debug_dir);
838 dir_error:
839 	ohci->debug_periodic = NULL;
840 	ohci->debug_async = NULL;
841 	ohci->debug_dir = NULL;
842 }
843 
844 static inline void remove_debug_files (struct ohci_hcd *ohci)
845 {
846 	debugfs_remove(ohci->debug_registers);
847 	debugfs_remove(ohci->debug_periodic);
848 	debugfs_remove(ohci->debug_async);
849 	debugfs_remove(ohci->debug_dir);
850 }
851 
852 #endif
853 
854 /*-------------------------------------------------------------------------*/
855 
856