/*
   * OHCI HCD (Host Controller Driver) for USB.
   *
   * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
   * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
   *
   * This file is licenced under the GPL.
   */
  
  /*-------------------------------------------------------------------------*/
  
  #define edstring(ed_type) ({ char *temp; \
  	switch (ed_type) { \
  	case PIPE_CONTROL:	temp = "ctrl"; break; \
  	case PIPE_BULK:		temp = "bulk"; break; \
  	case PIPE_INTERRUPT:	temp = "intr"; break; \
  	default:		temp = "isoc"; break; \
  	} temp;})
  #define pipestring(pipe) edstring(usb_pipetype(pipe))
  
  
  #define ohci_dbg_sw(ohci, next, size, format, arg...) \
  	do { \
  	if (next != NULL) { \
  		unsigned s_len; \
  		s_len = scnprintf (*next, *size, format, ## arg ); \
  		*size -= s_len; *next += s_len; \
  	} else \
  		ohci_dbg(ohci,format, ## arg ); \
  	} while (0);
  
  /* Version for use where "next" is the address of a local variable */
  #define ohci_dbg_nosw(ohci, next, size, format, arg...) \
  	do { \
  		unsigned s_len; \
  		s_len = scnprintf(*next, *size, format, ## arg); \
  		*size -= s_len; *next += s_len; \
  	} while (0);
  
  
  static void ohci_dump_intr_mask (
  	struct ohci_hcd *ohci,
  	char *label,
  	u32 mask,
  	char **next,
  	unsigned *size)
  {
  	ohci_dbg_sw (ohci, next, size, "%s 0x%08x%s%s%s%s%s%s%s%s%s
  ",
  		label,
  		mask,
  		(mask & OHCI_INTR_MIE) ? " MIE" : "",
  		(mask & OHCI_INTR_OC) ? " OC" : "",
  		(mask & OHCI_INTR_RHSC) ? " RHSC" : "",
  		(mask & OHCI_INTR_FNO) ? " FNO" : "",
  		(mask & OHCI_INTR_UE) ? " UE" : "",
  		(mask & OHCI_INTR_RD) ? " RD" : "",
  		(mask & OHCI_INTR_SF) ? " SF" : "",
  		(mask & OHCI_INTR_WDH) ? " WDH" : "",
  		(mask & OHCI_INTR_SO) ? " SO" : ""
  		);
  }
  
  static void maybe_print_eds (
  	struct ohci_hcd *ohci,
  	char *label,
  	u32 value,
  	char **next,
  	unsigned *size)
  {
  	if (value)
  		ohci_dbg_sw (ohci, next, size, "%s %08x
  ", label, value);
  }
  
  static char *hcfs2string (int state)
  {
  	switch (state) {
  		case OHCI_USB_RESET:	return "reset";
  		case OHCI_USB_RESUME:	return "resume";
  		case OHCI_USB_OPER:	return "operational";
  		case OHCI_USB_SUSPEND:	return "suspend";
  	}
  	return "?";
  }
  
  static const char *rh_state_string(struct ohci_hcd *ohci)
  {
  	switch (ohci->rh_state) {
  	case OHCI_RH_HALTED:
  		return "halted";
  	case OHCI_RH_SUSPENDED:
  		return "suspended";
  	case OHCI_RH_RUNNING:
  		return "running";
  	}
  	return "?";
  }
  
  // dump control and status registers
  static void
  ohci_dump_status (struct ohci_hcd *controller, char **next, unsigned *size)
  {
  	struct ohci_regs __iomem *regs = controller->regs;
  	u32			temp;
  
  	temp = ohci_readl (controller, &regs->revision) & 0xff;
  	ohci_dbg_sw (controller, next, size,
  		"OHCI %d.%d, %s legacy support registers, rh state %s
  ",
  		0x03 & (temp >> 4), (temp & 0x0f),
  		(temp & 0x0100) ? "with" : "NO",
  		rh_state_string(controller));
  
  	temp = ohci_readl (controller, &regs->control);
  	ohci_dbg_sw (controller, next, size,
  		"control 0x%03x%s%s%s HCFS=%s%s%s%s%s CBSR=%d
  ",
  		temp,
  		(temp & OHCI_CTRL_RWE) ? " RWE" : "",
  		(temp & OHCI_CTRL_RWC) ? " RWC" : "",
  		(temp & OHCI_CTRL_IR) ? " IR" : "",
  		hcfs2string (temp & OHCI_CTRL_HCFS),
  		(temp & OHCI_CTRL_BLE) ? " BLE" : "",
  		(temp & OHCI_CTRL_CLE) ? " CLE" : "",
  		(temp & OHCI_CTRL_IE) ? " IE" : "",
  		(temp & OHCI_CTRL_PLE) ? " PLE" : "",
  		temp & OHCI_CTRL_CBSR
  		);
  
  	temp = ohci_readl (controller, &regs->cmdstatus);
  	ohci_dbg_sw (controller, next, size,
  		"cmdstatus 0x%05x SOC=%d%s%s%s%s
  ", temp,
  		(temp & OHCI_SOC) >> 16,
  		(temp & OHCI_OCR) ? " OCR" : "",
  		(temp & OHCI_BLF) ? " BLF" : "",
  		(temp & OHCI_CLF) ? " CLF" : "",
  		(temp & OHCI_HCR) ? " HCR" : ""
  		);
  
  	ohci_dump_intr_mask (controller, "intrstatus",
  			ohci_readl (controller, &regs->intrstatus),
  			next, size);
  	ohci_dump_intr_mask (controller, "intrenable",
  			ohci_readl (controller, &regs->intrenable),
  			next, size);
  	// intrdisable always same as intrenable
  
  	maybe_print_eds (controller, "ed_periodcurrent",
  			ohci_readl (controller, &regs->ed_periodcurrent),
  			next, size);
  
  	maybe_print_eds (controller, "ed_controlhead",
  			ohci_readl (controller, &regs->ed_controlhead),
  			next, size);
  	maybe_print_eds (controller, "ed_controlcurrent",
  			ohci_readl (controller, &regs->ed_controlcurrent),
  			next, size);
  
  	maybe_print_eds (controller, "ed_bulkhead",
  			ohci_readl (controller, &regs->ed_bulkhead),
  			next, size);
  	maybe_print_eds (controller, "ed_bulkcurrent",
  			ohci_readl (controller, &regs->ed_bulkcurrent),
  			next, size);
  
  	maybe_print_eds (controller, "donehead",
  			ohci_readl (controller, &regs->donehead), next, size);
  }
  
  #define dbg_port_sw(hc,num,value,next,size) \
  	ohci_dbg_sw (hc, next, size, \
  		"roothub.portstatus [%d] " \
  		"0x%08x%s%s%s%s%s%s%s%s%s%s%s%s
  ", \
  		num, temp, \
  		(temp & RH_PS_PRSC) ? " PRSC" : "", \
  		(temp & RH_PS_OCIC) ? " OCIC" : "", \
  		(temp & RH_PS_PSSC) ? " PSSC" : "", \
  		(temp & RH_PS_PESC) ? " PESC" : "", \
  		(temp & RH_PS_CSC) ? " CSC" : "", \
  		\
  		(temp & RH_PS_LSDA) ? " LSDA" : "", \
  		(temp & RH_PS_PPS) ? " PPS" : "", \
  		(temp & RH_PS_PRS) ? " PRS" : "", \
  		(temp & RH_PS_POCI) ? " POCI" : "", \
  		(temp & RH_PS_PSS) ? " PSS" : "", \
  		\
  		(temp & RH_PS_PES) ? " PES" : "", \
  		(temp & RH_PS_CCS) ? " CCS" : "" \
  		);
  
  
  static void
  ohci_dump_roothub (
  	struct ohci_hcd *controller,
  	int verbose,
  	char **next,
  	unsigned *size)
  {
  	u32			temp, i;
  
  	temp = roothub_a (controller);
  	if (temp == ~(u32)0)
  		return;
  
  	if (verbose) {
  		ohci_dbg_sw (controller, next, size,
  			"roothub.a %08x POTPGT=%d%s%s%s%s%s NDP=%d(%d)
  ", temp,
  			((temp & RH_A_POTPGT) >> 24) & 0xff,
  			(temp & RH_A_NOCP) ? " NOCP" : "",
  			(temp & RH_A_OCPM) ? " OCPM" : "",
  			(temp & RH_A_DT) ? " DT" : "",
  			(temp & RH_A_NPS) ? " NPS" : "",
  			(temp & RH_A_PSM) ? " PSM" : "",
  			(temp & RH_A_NDP), controller->num_ports
  			);
  		temp = roothub_b (controller);
  		ohci_dbg_sw (controller, next, size,
  			"roothub.b %08x PPCM=%04x DR=%04x
  ",
  			temp,
  			(temp & RH_B_PPCM) >> 16,
  			(temp & RH_B_DR)
  			);
  		temp = roothub_status (controller);
  		ohci_dbg_sw (controller, next, size,
  			"roothub.status %08x%s%s%s%s%s%s
  ",
  			temp,
  			(temp & RH_HS_CRWE) ? " CRWE" : "",
  			(temp & RH_HS_OCIC) ? " OCIC" : "",
  			(temp & RH_HS_LPSC) ? " LPSC" : "",
  			(temp & RH_HS_DRWE) ? " DRWE" : "",
  			(temp & RH_HS_OCI) ? " OCI" : "",
  			(temp & RH_HS_LPS) ? " LPS" : ""
  			);
  	}
  
  	for (i = 0; i < controller->num_ports; i++) {
  		temp = roothub_portstatus (controller, i);
  		dbg_port_sw (controller, i, temp, next, size);
  	}
  }
  
  static void ohci_dump(struct ohci_hcd *controller)
  {
  	ohci_dbg (controller, "OHCI controller state
  ");
  
  	// dumps some of the state we know about
  	ohci_dump_status (controller, NULL, NULL);
  	if (controller->hcca)
  		ohci_dbg (controller,
  			"hcca frame #%04x
  ", ohci_frame_no(controller));
  	ohci_dump_roothub (controller, 1, NULL, NULL);
  }
  
  static const char data0 [] = "DATA0";
  static const char data1 [] = "DATA1";
  
  static void ohci_dump_td (const struct ohci_hcd *ohci, const char *label,
  		const struct td *td)
  {
  	u32	tmp = hc32_to_cpup (ohci, &td->hwINFO);
  
  	ohci_dbg (ohci, "%s td %p%s; urb %p index %d; hw next td %08x
  ",
  		label, td,
  		(tmp & TD_DONE) ? " (DONE)" : "",
  		td->urb, td->index,
  		hc32_to_cpup (ohci, &td->hwNextTD));
  	if ((tmp & TD_ISO) == 0) {
  		const char	*toggle, *pid;
  		u32	cbp, be;
  
  		switch (tmp & TD_T) {
  		case TD_T_DATA0: toggle = data0; break;
  		case TD_T_DATA1: toggle = data1; break;
  		case TD_T_TOGGLE: toggle = "(CARRY)"; break;
  		default: toggle = "(?)"; break;
  		}
  		switch (tmp & TD_DP) {
  		case TD_DP_SETUP: pid = "SETUP"; break;
  		case TD_DP_IN: pid = "IN"; break;
  		case TD_DP_OUT: pid = "OUT"; break;
  		default: pid = "(bad pid)"; break;
  		}
  		ohci_dbg (ohci, "     info %08x CC=%x %s DI=%d %s %s
  ", tmp,
  			TD_CC_GET(tmp), /* EC, */ toggle,
  			(tmp & TD_DI) >> 21, pid,
  			(tmp & TD_R) ? "R" : "");
  		cbp = hc32_to_cpup (ohci, &td->hwCBP);
  		be = hc32_to_cpup (ohci, &td->hwBE);
  		ohci_dbg (ohci, "     cbp %08x be %08x (len %d)
  ", cbp, be,
  			cbp ? (be + 1 - cbp) : 0);
  	} else {
  		unsigned	i;
  		ohci_dbg (ohci, "  info %08x CC=%x FC=%d DI=%d SF=%04x
  ", tmp,
  			TD_CC_GET(tmp),
  			(tmp >> 24) & 0x07,
  			(tmp & TD_DI) >> 21,
  			tmp & 0x0000ffff);
  		ohci_dbg (ohci, "  bp0 %08x be %08x
  ",
  			hc32_to_cpup (ohci, &td->hwCBP) & ~0x0fff,
  			hc32_to_cpup (ohci, &td->hwBE));
  		for (i = 0; i < MAXPSW; i++) {
  			u16	psw = ohci_hwPSW (ohci, td, i);
  			int	cc = (psw >> 12) & 0x0f;
  			ohci_dbg (ohci, "    psw [%d] = %2x, CC=%x %s=%d
  ", i,
  				psw, cc,
  				(cc >= 0x0e) ? "OFFSET" : "SIZE",
  				psw & 0x0fff);
  		}
  	}
  }
  
  /* caller MUST own hcd spinlock if verbose is set! */
  static void __maybe_unused
  ohci_dump_ed (const struct ohci_hcd *ohci, const char *label,
  		const struct ed *ed, int verbose)
  {
  	u32	tmp = hc32_to_cpu (ohci, ed->hwINFO);
  	char	*type = "";
  
  	ohci_dbg (ohci, "%s, ed %p state 0x%x type %s; next ed %08x
  ",
  		label,
  		ed, ed->state, edstring (ed->type),
  		hc32_to_cpup (ohci, &ed->hwNextED));
  	switch (tmp & (ED_IN|ED_OUT)) {
  	case ED_OUT: type = "-OUT"; break;
  	case ED_IN: type = "-IN"; break;
  	/* else from TDs ... control */
  	}
  	ohci_dbg (ohci,
  		"  info %08x MAX=%d%s%s%s%s EP=%d%s DEV=%d
  ", tmp,
  		0x03ff & (tmp >> 16),
  		(tmp & ED_DEQUEUE) ? " DQ" : "",
  		(tmp & ED_ISO) ? " ISO" : "",
  		(tmp & ED_SKIP) ? " SKIP" : "",
  		(tmp & ED_LOWSPEED) ? " LOW" : "",
  		0x000f & (tmp >> 7),
  		type,
  		0x007f & tmp);
  	tmp = hc32_to_cpup (ohci, &ed->hwHeadP);
  	ohci_dbg (ohci, "  tds: head %08x %s%s tail %08x%s
  ",
  		tmp,
  		(tmp & ED_C) ? data1 : data0,
  		(tmp & ED_H) ? " HALT" : "",
  		hc32_to_cpup (ohci, &ed->hwTailP),
  		verbose ? "" : " (not listing)");
  	if (verbose) {
  		struct list_head	*tmp;
  
  		/* use ed->td_list because HC concurrently modifies
  		 * hwNextTD as it accumulates ed_donelist.
  		 */
  		list_for_each (tmp, &ed->td_list) {
  			struct td		*td;
  			td = list_entry (tmp, struct td, td_list);
  			ohci_dump_td (ohci, "  ->", td);
  		}
  	}
  }
  
  /*-------------------------------------------------------------------------*/
  
  static int debug_async_open(struct inode *, struct file *);
  static int debug_periodic_open(struct inode *, struct file *);
  static int debug_registers_open(struct inode *, struct file *);
  static int debug_async_open(struct inode *, struct file *);
  static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
  static int debug_close(struct inode *, struct file *);
  
  static const struct file_operations debug_async_fops = {
  	.owner		= THIS_MODULE,
  	.open		= debug_async_open,
  	.read		= debug_output,
  	.release	= debug_close,
  	.llseek		= default_llseek,
  };
  static const struct file_operations debug_periodic_fops = {
  	.owner		= THIS_MODULE,
  	.open		= debug_periodic_open,
  	.read		= debug_output,
  	.release	= debug_close,
  	.llseek		= default_llseek,
  };
  static const struct file_operations debug_registers_fops = {
  	.owner		= THIS_MODULE,
  	.open		= debug_registers_open,
  	.read		= debug_output,
  	.release	= debug_close,
  	.llseek		= default_llseek,
  };
  
  static struct dentry *ohci_debug_root;
  
  struct debug_buffer {
  	ssize_t (*fill_func)(struct debug_buffer *);	/* fill method */
  	struct ohci_hcd *ohci;
  	struct mutex mutex;	/* protect filling of buffer */
  	size_t count;		/* number of characters filled into buffer */
  	char *page;
  };
  
  static ssize_t
  show_list (struct ohci_hcd *ohci, char *buf, size_t count, struct ed *ed)
  {
  	unsigned		temp, size = count;
  
  	if (!ed)
  		return 0;
  
  	/* print first --> last */
  	while (ed->ed_prev)
  		ed = ed->ed_prev;
  
  	/* dump a snapshot of the bulk or control schedule */
  	while (ed) {
  		u32		info = hc32_to_cpu (ohci, ed->hwINFO);
  		u32		headp = hc32_to_cpu (ohci, ed->hwHeadP);
  		struct list_head *entry;
  		struct td	*td;
  
  		temp = scnprintf (buf, size,
  			"ed/%p %cs dev%d ep%d%s max %d %08x%s%s %s",
  			ed,
  			(info & ED_LOWSPEED) ? 'l' : 'f',
  			info & 0x7f,
  			(info >> 7) & 0xf,
  			(info & ED_IN) ? "in" : "out",
  			0x03ff & (info >> 16),
  			info,
  			(info & ED_SKIP) ? " s" : "",
  			(headp & ED_H) ? " H" : "",
  			(headp & ED_C) ? data1 : data0);
  		size -= temp;
  		buf += temp;
  
  		list_for_each (entry, &ed->td_list) {
  			u32		cbp, be;
  
  			td = list_entry (entry, struct td, td_list);
  			info = hc32_to_cpup (ohci, &td->hwINFO);
  			cbp = hc32_to_cpup (ohci, &td->hwCBP);
  			be = hc32_to_cpup (ohci, &td->hwBE);
  			temp = scnprintf (buf, size,
  					"
  \ttd %p %s %d cc=%x urb %p (%08x)",
  					td,
  					({ char *pid;
  					switch (info & TD_DP) {
  					case TD_DP_SETUP: pid = "setup"; break;
  					case TD_DP_IN: pid = "in"; break;
  					case TD_DP_OUT: pid = "out"; break;
  					default: pid = "(?)"; break;
  					 } pid;}),
  					cbp ? (be + 1 - cbp) : 0,
  					TD_CC_GET (info), td->urb, info);
  			size -= temp;
  			buf += temp;
  		}
  
  		temp = scnprintf (buf, size, "
  ");
  		size -= temp;
  		buf += temp;
  
  		ed = ed->ed_next;
  	}
  	return count - size;
  }
  
  static ssize_t fill_async_buffer(struct debug_buffer *buf)
  {
  	struct ohci_hcd		*ohci;
  	size_t			temp, size;
  	unsigned long		flags;
  
  	ohci = buf->ohci;
  	size = PAGE_SIZE;
  
  	/* display control and bulk lists together, for simplicity */
  	spin_lock_irqsave (&ohci->lock, flags);
  	temp = show_list(ohci, buf->page, size, ohci->ed_controltail);
  	temp += show_list(ohci, buf->page + temp, size - temp,
  			  ohci->ed_bulktail);
  	spin_unlock_irqrestore (&ohci->lock, flags);
  
  	return temp;
  }
  
  #define DBG_SCHED_LIMIT 64
  
  static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
  {
  	struct ohci_hcd		*ohci;
  	struct ed		**seen, *ed;
  	unsigned long		flags;
  	unsigned		temp, size, seen_count;
  	char			*next;
  	unsigned		i;
  
  	if (!(seen = kmalloc (DBG_SCHED_LIMIT * sizeof *seen, GFP_ATOMIC)))
  		return 0;
  	seen_count = 0;
  
  	ohci = buf->ohci;
  	next = buf->page;
  	size = PAGE_SIZE;
  
  	temp = scnprintf (next, size, "size = %d
  ", NUM_INTS);
  	size -= temp;
  	next += temp;
  
  	/* dump a snapshot of the periodic schedule (and load) */
  	spin_lock_irqsave (&ohci->lock, flags);
  	for (i = 0; i < NUM_INTS; i++) {
  		if (!(ed = ohci->periodic [i]))
  			continue;
  
  		temp = scnprintf (next, size, "%2d [%3d]:", i, ohci->load [i]);
  		size -= temp;
  		next += temp;
  
  		do {
  			temp = scnprintf (next, size, " ed%d/%p",
  				ed->interval, ed);
  			size -= temp;
  			next += temp;
  			for (temp = 0; temp < seen_count; temp++) {
  				if (seen [temp] == ed)
  					break;
  			}
  
  			/* show more info the first time around */
  			if (temp == seen_count) {
  				u32	info = hc32_to_cpu (ohci, ed->hwINFO);
  				struct list_head	*entry;
  				unsigned		qlen = 0;
  
  				/* qlen measured here in TDs, not urbs */
  				list_for_each (entry, &ed->td_list)
  					qlen++;
  
  				temp = scnprintf (next, size,
  					" (%cs dev%d ep%d%s-%s qlen %u"
  					" max %d %08x%s%s)",
  					(info & ED_LOWSPEED) ? 'l' : 'f',
  					info & 0x7f,
  					(info >> 7) & 0xf,
  					(info & ED_IN) ? "in" : "out",
  					(info & ED_ISO) ? "iso" : "int",
  					qlen,
  					0x03ff & (info >> 16),
  					info,
  					(info & ED_SKIP) ? " K" : "",
  					(ed->hwHeadP &
  						cpu_to_hc32(ohci, ED_H)) ?
  							" H" : "");
  				size -= temp;
  				next += temp;
  
  				if (seen_count < DBG_SCHED_LIMIT)
  					seen [seen_count++] = ed;
  
  				ed = ed->ed_next;
  
  			} else {
  				/* we've seen it and what's after */
  				temp = 0;
  				ed = NULL;
  			}
  
  		} while (ed);
  
  		temp = scnprintf (next, size, "
  ");
  		size -= temp;
  		next += temp;
  	}
  	spin_unlock_irqrestore (&ohci->lock, flags);
  	kfree (seen);
  
  	return PAGE_SIZE - size;
  }
  #undef DBG_SCHED_LIMIT
  
  static ssize_t fill_registers_buffer(struct debug_buffer *buf)
  {
  	struct usb_hcd		*hcd;
  	struct ohci_hcd		*ohci;
  	struct ohci_regs __iomem *regs;
  	unsigned long		flags;
  	unsigned		temp, size;
  	char			*next;
  	u32			rdata;
  
  	ohci = buf->ohci;
  	hcd = ohci_to_hcd(ohci);
  	regs = ohci->regs;
  	next = buf->page;
  	size = PAGE_SIZE;
  
  	spin_lock_irqsave (&ohci->lock, flags);
  
  	/* dump driver info, then registers in spec order */
  
  	ohci_dbg_nosw(ohci, &next, &size,
  		"bus %s, device %s
  "
  		"%s
  "
  		"%s
  ",
  		hcd->self.controller->bus->name,
  		dev_name(hcd->self.controller),
  		hcd->product_desc,
  		hcd_name);
  
  	if (!HCD_HW_ACCESSIBLE(hcd)) {
  		size -= scnprintf (next, size,
  			"SUSPENDED (no register access)
  ");
  		goto done;
  	}
  
  	ohci_dump_status(ohci, &next, &size);
  
  	/* hcca */
  	if (ohci->hcca)
  		ohci_dbg_nosw(ohci, &next, &size,
  			"hcca frame 0x%04x
  ", ohci_frame_no(ohci));
  
  	/* other registers mostly affect frame timings */
  	rdata = ohci_readl (ohci, &regs->fminterval);
  	temp = scnprintf (next, size,
  			"fmintvl 0x%08x %sFSMPS=0x%04x FI=0x%04x
  ",
  			rdata, (rdata >> 31) ? "FIT " : "",
  			(rdata >> 16) & 0xefff, rdata & 0xffff);
  	size -= temp;
  	next += temp;
  
  	rdata = ohci_readl (ohci, &regs->fmremaining);
  	temp = scnprintf (next, size, "fmremaining 0x%08x %sFR=0x%04x
  ",
  			rdata, (rdata >> 31) ? "FRT " : "",
  			rdata & 0x3fff);
  	size -= temp;
  	next += temp;
  
  	rdata = ohci_readl (ohci, &regs->periodicstart);
  	temp = scnprintf (next, size, "periodicstart 0x%04x
  ",
  			rdata & 0x3fff);
  	size -= temp;
  	next += temp;
  
  	rdata = ohci_readl (ohci, &regs->lsthresh);
  	temp = scnprintf (next, size, "lsthresh 0x%04x
  ",
  			rdata & 0x3fff);
  	size -= temp;
  	next += temp;
  
  	temp = scnprintf (next, size, "hub poll timer %s
  ",
  			HCD_POLL_RH(ohci_to_hcd(ohci)) ? "ON" : "off");
  	size -= temp;
  	next += temp;
  
  	/* roothub */
  	ohci_dump_roothub (ohci, 1, &next, &size);
  
  done:
  	spin_unlock_irqrestore (&ohci->lock, flags);
  
  	return PAGE_SIZE - size;
  }
  
  static struct debug_buffer *alloc_buffer(struct ohci_hcd *ohci,
  				ssize_t (*fill_func)(struct debug_buffer *))
  {
  	struct debug_buffer *buf;
  
  	buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
  
  	if (buf) {
  		buf->ohci = ohci;
  		buf->fill_func = fill_func;
  		mutex_init(&buf->mutex);
  	}
  
  	return buf;
  }
  
  static int fill_buffer(struct debug_buffer *buf)
  {
  	int ret = 0;
  
  	if (!buf->page)
  		buf->page = (char *)get_zeroed_page(GFP_KERNEL);
  
  	if (!buf->page) {
  		ret = -ENOMEM;
  		goto out;
  	}
  
  	ret = buf->fill_func(buf);
  
  	if (ret >= 0) {
  		buf->count = ret;
  		ret = 0;
  	}
  
  out:
  	return ret;
  }
  
  static ssize_t debug_output(struct file *file, char __user *user_buf,
  			size_t len, loff_t *offset)
  {
  	struct debug_buffer *buf = file->private_data;
  	int ret = 0;
  
  	mutex_lock(&buf->mutex);
  	if (buf->count == 0) {
  		ret = fill_buffer(buf);
  		if (ret != 0) {
  			mutex_unlock(&buf->mutex);
  			goto out;
  		}
  	}
  	mutex_unlock(&buf->mutex);
  
  	ret = simple_read_from_buffer(user_buf, len, offset,
  				      buf->page, buf->count);
  
  out:
  	return ret;
  
  }
  
  static int debug_close(struct inode *inode, struct file *file)
  {
  	struct debug_buffer *buf = file->private_data;
  
  	if (buf) {
  		if (buf->page)
  			free_page((unsigned long)buf->page);
  		kfree(buf);
  	}
  
  	return 0;
  }
  static int debug_async_open(struct inode *inode, struct file *file)
  {
  	file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);
  
  	return file->private_data ? 0 : -ENOMEM;
  }
  
  static int debug_periodic_open(struct inode *inode, struct file *file)
  {
  	file->private_data = alloc_buffer(inode->i_private,
  					  fill_periodic_buffer);
  
  	return file->private_data ? 0 : -ENOMEM;
  }
  
  static int debug_registers_open(struct inode *inode, struct file *file)
  {
  	file->private_data = alloc_buffer(inode->i_private,
  					  fill_registers_buffer);
  
  	return file->private_data ? 0 : -ENOMEM;
  }
  static inline void create_debug_files (struct ohci_hcd *ohci)
  {
  	struct usb_bus *bus = &ohci_to_hcd(ohci)->self;
  
  	ohci->debug_dir = debugfs_create_dir(bus->bus_name, ohci_debug_root);
  	if (!ohci->debug_dir)
  		goto dir_error;
  
  	ohci->debug_async = debugfs_create_file("async", S_IRUGO,
  						ohci->debug_dir, ohci,
  						&debug_async_fops);
  	if (!ohci->debug_async)
  		goto async_error;
  
  	ohci->debug_periodic = debugfs_create_file("periodic", S_IRUGO,
  						   ohci->debug_dir, ohci,
  						   &debug_periodic_fops);
  	if (!ohci->debug_periodic)
  		goto periodic_error;
  
  	ohci->debug_registers = debugfs_create_file("registers", S_IRUGO,
  						    ohci->debug_dir, ohci,
  						    &debug_registers_fops);
  	if (!ohci->debug_registers)
  		goto registers_error;
  
  	ohci_dbg (ohci, "created debug files
  ");
  	return;
  
  registers_error:
  	debugfs_remove(ohci->debug_periodic);
  periodic_error:
  	debugfs_remove(ohci->debug_async);
  async_error:
  	debugfs_remove(ohci->debug_dir);
  dir_error:
  	ohci->debug_periodic = NULL;
  	ohci->debug_async = NULL;
  	ohci->debug_dir = NULL;
  }
  
  static inline void remove_debug_files (struct ohci_hcd *ohci)
  {
  	debugfs_remove(ohci->debug_registers);
  	debugfs_remove(ohci->debug_periodic);
  	debugfs_remove(ohci->debug_async);
  	debugfs_remove(ohci->debug_dir);
  }
  
  /*-------------------------------------------------------------------------*/