Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 785 insertions, 0 deletions

diff --git a/drivers/usb/host/ohci-dbg.c b/drivers/usb/host/ohci-dbg.c
new file mode 100644
index 000000000..4f267dc93
--- /dev/null
+++ b/drivers/usb/host/ohci-dbg.c
@@ -0,0 +1,785 @@
+// SPDX-License-Identifier: GPL-1.0+
+/*
+ * 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\n",
+		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\n", 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\n",
+		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\n",
+		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\n", 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\n", \
+		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)\n", 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\n",
+			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\n",
+			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\n");
+
+	// dumps some of the state we know about
+	ohci_dump_status (controller, NULL, NULL);
+	if (controller->hcca)
+		ohci_dbg (controller,
+			"hcca frame #%04x\n", 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\n",
+		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\n", 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)\n", cbp, be,
+			cbp ? (be + 1 - cbp) : 0);
+	} else {
+		unsigned	i;
+		ohci_dbg (ohci, "  info %08x CC=%x FC=%d DI=%d SF=%04x\n", tmp,
+			TD_CC_GET(tmp),
+			(tmp >> 24) & 0x07,
+			(tmp & TD_DI) >> 21,
+			tmp & 0x0000ffff);
+		ohci_dbg (ohci, "  bp0 %08x be %08x\n",
+			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\n", 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\n",
+		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\n", 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\n",
+		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,
+					"\n\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, "\n");
+		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;
+
+	seen = kmalloc_array(DBG_SCHED_LIMIT, sizeof(*seen), GFP_ATOMIC);
+	if (!seen)
+		return 0;
+	seen_count = 0;
+
+	ohci = buf->ohci;
+	next = buf->page;
+	size = PAGE_SIZE;
+
+	temp = scnprintf (next, size, "size = %d\n", 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++) {
+		ed = ohci->periodic[i];
+		if (!ed)
+			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, "\n");
+		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\n"
+		"%s\n"
+		"%s\n",
+		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)\n");
+		goto done;
+	}
+
+	ohci_dump_status(ohci, &next, &size);
+
+	/* hcca */
+	if (ohci->hcca)
+		ohci_dbg_nosw(ohci, &next, &size,
+			"hcca frame 0x%04x\n", 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\n",
+			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\n",
+			rdata, (rdata >> 31) ? "FRT " : "",
+			rdata & 0x3fff);
+	size -= temp;
+	next += temp;
+
+	rdata = ohci_readl (ohci, &regs->periodicstart);
+	temp = scnprintf (next, size, "periodicstart 0x%04x\n",
+			rdata & 0x3fff);
+	size -= temp;
+	next += temp;
+
+	rdata = ohci_readl (ohci, &regs->lsthresh);
+	temp = scnprintf (next, size, "lsthresh 0x%04x\n",
+			rdata & 0x3fff);
+	size -= temp;
+	next += temp;
+
+	temp = scnprintf (next, size, "hub poll timer %s\n",
+			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;
+	struct dentry *root;
+
+	root = debugfs_create_dir(bus->bus_name, ohci_debug_root);
+	ohci->debug_dir = root;
+
+	debugfs_create_file("async", S_IRUGO, root, ohci, &debug_async_fops);
+	debugfs_create_file("periodic", S_IRUGO, root, ohci,
+			    &debug_periodic_fops);
+	debugfs_create_file("registers", S_IRUGO, root, ohci,
+			    &debug_registers_fops);
+
+	ohci_dbg (ohci, "created debug files\n");
+}
+
+static inline void remove_debug_files (struct ohci_hcd *ohci)
+{
+	debugfs_remove_recursive(ohci->debug_dir);
+}
+
+/*-------------------------------------------------------------------------*/
+