USB: Implement support for EHCI with big endian MMIO

This patch implements supports for EHCI controllers whose MMIO
registers are big endian and enables that functionality for
the Toshiba SCC chip. It does _not_ add support for big endian
in-memory data structures as this is not needed for that chip
and I hope it will never be.

The guts of the patch are to convert readl(...) to
ehci_readl(ehci, ...) and similarly for register writes.

Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index faabce8..8325998 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -67,6 +67,11 @@
 
 	  If unsure, say N.
 
+config USB_EHCI_BIG_ENDIAN_MMIO
+	bool
+	depends on USB_EHCI_HCD
+	default n
+
 config USB_ISP116X_HCD
 	tristate "ISP116X HCD support"
 	depends on USB
diff --git a/drivers/usb/host/ehci-dbg.c b/drivers/usb/host/ehci-dbg.c
index 56349d2..246afea 100644
--- a/drivers/usb/host/ehci-dbg.c
+++ b/drivers/usb/host/ehci-dbg.c
@@ -43,7 +43,7 @@
  */
 static void dbg_hcs_params (struct ehci_hcd *ehci, char *label)
 {
-	u32	params = readl (&ehci->caps->hcs_params);
+	u32	params = ehci_readl(ehci, &ehci->caps->hcs_params);
 
 	ehci_dbg (ehci,
 		"%s hcs_params 0x%x dbg=%d%s cc=%d pcc=%d%s%s ports=%d\n",
@@ -87,7 +87,7 @@
  * */
 static void dbg_hcc_params (struct ehci_hcd *ehci, char *label)
 {
-	u32	params = readl (&ehci->caps->hcc_params);
+	u32	params = ehci_readl(ehci, &ehci->caps->hcc_params);
 
 	if (HCC_ISOC_CACHE (params)) {
 		ehci_dbg (ehci,
@@ -653,7 +653,7 @@
 	}
 
 	/* Capability Registers */
-	i = HC_VERSION(readl (&ehci->caps->hc_capbase));
+	i = HC_VERSION(ehci_readl(ehci, &ehci->caps->hc_capbase));
 	temp = scnprintf (next, size,
 		"bus %s, device %s (driver " DRIVER_VERSION ")\n"
 		"%s\n"
@@ -673,7 +673,7 @@
 		unsigned	count = 256/4;
 
 		pdev = to_pci_dev(ehci_to_hcd(ehci)->self.controller);
-		offset = HCC_EXT_CAPS (readl (&ehci->caps->hcc_params));
+		offset = HCC_EXT_CAPS (ehci_readl(ehci, &ehci->caps->hcc_params));
 		while (offset && count--) {
 			pci_read_config_dword (pdev, offset, &cap);
 			switch (cap & 0xff) {
@@ -704,50 +704,50 @@
 #endif
 
 	// FIXME interpret both types of params
-	i = readl (&ehci->caps->hcs_params);
+	i = ehci_readl(ehci, &ehci->caps->hcs_params);
 	temp = scnprintf (next, size, "structural params 0x%08x\n", i);
 	size -= temp;
 	next += temp;
 
-	i = readl (&ehci->caps->hcc_params);
+	i = ehci_readl(ehci, &ehci->caps->hcc_params);
 	temp = scnprintf (next, size, "capability params 0x%08x\n", i);
 	size -= temp;
 	next += temp;
 
 	/* Operational Registers */
 	temp = dbg_status_buf (scratch, sizeof scratch, label,
-			readl (&ehci->regs->status));
+			ehci_readl(ehci, &ehci->regs->status));
 	temp = scnprintf (next, size, fmt, temp, scratch);
 	size -= temp;
 	next += temp;
 
 	temp = dbg_command_buf (scratch, sizeof scratch, label,
-			readl (&ehci->regs->command));
+			ehci_readl(ehci, &ehci->regs->command));
 	temp = scnprintf (next, size, fmt, temp, scratch);
 	size -= temp;
 	next += temp;
 
 	temp = dbg_intr_buf (scratch, sizeof scratch, label,
-			readl (&ehci->regs->intr_enable));
+			ehci_readl(ehci, &ehci->regs->intr_enable));
 	temp = scnprintf (next, size, fmt, temp, scratch);
 	size -= temp;
 	next += temp;
 
 	temp = scnprintf (next, size, "uframe %04x\n",
-			readl (&ehci->regs->frame_index));
+			ehci_readl(ehci, &ehci->regs->frame_index));
 	size -= temp;
 	next += temp;
 
 	for (i = 1; i <= HCS_N_PORTS (ehci->hcs_params); i++) {
 		temp = dbg_port_buf (scratch, sizeof scratch, label, i,
-				readl (&ehci->regs->port_status [i - 1]));
+				ehci_readl(ehci, &ehci->regs->port_status [i - 1]));
 		temp = scnprintf (next, size, fmt, temp, scratch);
 		size -= temp;
 		next += temp;
 		if (i == HCS_DEBUG_PORT(ehci->hcs_params) && ehci->debug) {
 			temp = scnprintf (next, size,
 					"    debug control %08x\n",
-					readl (&ehci->debug->control));
+					ehci_readl(ehci, &ehci->debug->control));
 			size -= temp;
 			next += temp;
 		}
diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 1a915e9..a524805 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -177,7 +177,7 @@
 	case FSL_USB2_PHY_NONE:
 		break;
 	}
-	writel(portsc, &ehci->regs->port_status[port_offset]);
+	ehci_writel(ehci, portsc, &ehci->regs->port_status[port_offset]);
 }
 
 static void mpc83xx_usb_setup(struct usb_hcd *hcd)
@@ -214,7 +214,7 @@
 	}
 
 	/* put controller in host mode. */
-	writel(0x00000003, non_ehci + FSL_SOC_USB_USBMODE);
+	ehci_writel(ehci, 0x00000003, non_ehci + FSL_SOC_USB_USBMODE);
 	out_be32(non_ehci + FSL_SOC_USB_PRICTRL, 0x0000000c);
 	out_be32(non_ehci + FSL_SOC_USB_AGECNTTHRSH, 0x00000040);
 	out_be32(non_ehci + FSL_SOC_USB_SICTRL, 0x00000001);
@@ -238,12 +238,12 @@
 	/* EHCI registers start at offset 0x100 */
 	ehci->caps = hcd->regs + 0x100;
 	ehci->regs = hcd->regs + 0x100 +
-	    HC_LENGTH(readl(&ehci->caps->hc_capbase));
+	    HC_LENGTH(ehci_readl(ehci, &ehci->caps->hc_capbase));
 	dbg_hcs_params(ehci, "reset");
 	dbg_hcc_params(ehci, "reset");
 
 	/* cache this readonly data; minimize chip reads */
-	ehci->hcs_params = readl(&ehci->caps->hcs_params);
+	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
 
 	retval = ehci_halt(ehci);
 	if (retval)
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 025d333..03d567e 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -157,12 +157,13 @@
  * before driver shutdown. But it also seems to be caused by bugs in cardbus
  * bridge shutdown:  shutting down the bridge before the devices using it.
  */
-static int handshake (void __iomem *ptr, u32 mask, u32 done, int usec)
+static int handshake (struct ehci_hcd *ehci, void __iomem *ptr,
+		      u32 mask, u32 done, int usec)
 {
 	u32	result;
 
 	do {
-		result = readl (ptr);
+		result = ehci_readl(ehci, ptr);
 		if (result == ~(u32)0)		/* card removed */
 			return -ENODEV;
 		result &= mask;
@@ -177,18 +178,19 @@
 /* force HC to halt state from unknown (EHCI spec section 2.3) */
 static int ehci_halt (struct ehci_hcd *ehci)
 {
-	u32	temp = readl (&ehci->regs->status);
+	u32	temp = ehci_readl(ehci, &ehci->regs->status);
 
 	/* disable any irqs left enabled by previous code */
-	writel (0, &ehci->regs->intr_enable);
+	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
 
 	if ((temp & STS_HALT) != 0)
 		return 0;
 
-	temp = readl (&ehci->regs->command);
+	temp = ehci_readl(ehci, &ehci->regs->command);
 	temp &= ~CMD_RUN;
-	writel (temp, &ehci->regs->command);
-	return handshake (&ehci->regs->status, STS_HALT, STS_HALT, 16 * 125);
+	ehci_writel(ehci, temp, &ehci->regs->command);
+	return handshake (ehci, &ehci->regs->status,
+			  STS_HALT, STS_HALT, 16 * 125);
 }
 
 /* put TDI/ARC silicon into EHCI mode */
@@ -198,23 +200,24 @@
 	u32		tmp;
 
 	reg_ptr = (u32 __iomem *)(((u8 __iomem *)ehci->regs) + 0x68);
-	tmp = readl (reg_ptr);
+	tmp = ehci_readl(ehci, reg_ptr);
 	tmp |= 0x3;
-	writel (tmp, reg_ptr);
+	ehci_writel(ehci, tmp, reg_ptr);
 }
 
 /* reset a non-running (STS_HALT == 1) controller */
 static int ehci_reset (struct ehci_hcd *ehci)
 {
 	int	retval;
-	u32	command = readl (&ehci->regs->command);
+	u32	command = ehci_readl(ehci, &ehci->regs->command);
 
 	command |= CMD_RESET;
 	dbg_cmd (ehci, "reset", command);
-	writel (command, &ehci->regs->command);
+	ehci_writel(ehci, command, &ehci->regs->command);
 	ehci_to_hcd(ehci)->state = HC_STATE_HALT;
 	ehci->next_statechange = jiffies;
-	retval = handshake (&ehci->regs->command, CMD_RESET, 0, 250 * 1000);
+	retval = handshake (ehci, &ehci->regs->command,
+			    CMD_RESET, 0, 250 * 1000);
 
 	if (retval)
 		return retval;
@@ -236,21 +239,21 @@
 #endif
 
 	/* wait for any schedule enables/disables to take effect */
-	temp = readl (&ehci->regs->command) << 10;
+	temp = ehci_readl(ehci, &ehci->regs->command) << 10;
 	temp &= STS_ASS | STS_PSS;
-	if (handshake (&ehci->regs->status, STS_ASS | STS_PSS,
+	if (handshake (ehci, &ehci->regs->status, STS_ASS | STS_PSS,
 				temp, 16 * 125) != 0) {
 		ehci_to_hcd(ehci)->state = HC_STATE_HALT;
 		return;
 	}
 
 	/* then disable anything that's still active */
-	temp = readl (&ehci->regs->command);
+	temp = ehci_readl(ehci, &ehci->regs->command);
 	temp &= ~(CMD_ASE | CMD_IAAD | CMD_PSE);
-	writel (temp, &ehci->regs->command);
+	ehci_writel(ehci, temp, &ehci->regs->command);
 
 	/* hardware can take 16 microframes to turn off ... */
-	if (handshake (&ehci->regs->status, STS_ASS | STS_PSS,
+	if (handshake (ehci, &ehci->regs->status, STS_ASS | STS_PSS,
 				0, 16 * 125) != 0) {
 		ehci_to_hcd(ehci)->state = HC_STATE_HALT;
 		return;
@@ -277,11 +280,11 @@
 
 	/* lost IAA irqs wedge things badly; seen with a vt8235 */
 	if (ehci->reclaim) {
-		u32		status = readl (&ehci->regs->status);
+		u32		status = ehci_readl(ehci, &ehci->regs->status);
 		if (status & STS_IAA) {
 			ehci_vdbg (ehci, "lost IAA\n");
 			COUNT (ehci->stats.lost_iaa);
-			writel (STS_IAA, &ehci->regs->status);
+			ehci_writel(ehci, STS_IAA, &ehci->regs->status);
 			ehci->reclaim_ready = 1;
 		}
 	}
@@ -309,7 +312,7 @@
 	(void) ehci_halt (ehci);
 
 	/* make BIOS/etc use companion controller during reboot */
-	writel (0, &ehci->regs->configured_flag);
+	ehci_writel(ehci, 0, &ehci->regs->configured_flag);
 }
 
 static void ehci_port_power (struct ehci_hcd *ehci, int is_on)
@@ -379,11 +382,11 @@
 		ehci_quiesce (ehci);
 
 	ehci_reset (ehci);
-	writel (0, &ehci->regs->intr_enable);
+	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
 	spin_unlock_irq(&ehci->lock);
 
 	/* let companion controllers work when we aren't */
-	writel (0, &ehci->regs->configured_flag);
+	ehci_writel(ehci, 0, &ehci->regs->configured_flag);
 
 	remove_debug_files (ehci);
 
@@ -402,7 +405,8 @@
 		ehci->stats.complete, ehci->stats.unlink);
 #endif
 
-	dbg_status (ehci, "ehci_stop completed", readl (&ehci->regs->status));
+	dbg_status (ehci, "ehci_stop completed",
+		    ehci_readl(ehci, &ehci->regs->status));
 }
 
 /* one-time init, only for memory state */
@@ -428,7 +432,7 @@
 		return retval;
 
 	/* controllers may cache some of the periodic schedule ... */
-	hcc_params = readl(&ehci->caps->hcc_params);
+	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);
 	if (HCC_ISOC_CACHE(hcc_params))		// full frame cache
 		ehci->i_thresh = 8;
 	else					// N microframes cached
@@ -501,8 +505,8 @@
 		ehci_mem_cleanup(ehci);
 		return retval;
 	}
-	writel(ehci->periodic_dma, &ehci->regs->frame_list);
-	writel((u32)ehci->async->qh_dma, &ehci->regs->async_next);
+	ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
+	ehci_writel(ehci, (u32)ehci->async->qh_dma, &ehci->regs->async_next);
 
 	/*
 	 * hcc_params controls whether ehci->regs->segment must (!!!)
@@ -516,9 +520,9 @@
 	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
 	 * host side drivers though.
 	 */
-	hcc_params = readl(&ehci->caps->hcc_params);
+	hcc_params = ehci_readl(ehci, &ehci->caps->hcc_params);
 	if (HCC_64BIT_ADDR(hcc_params)) {
-		writel(0, &ehci->regs->segment);
+		ehci_writel(ehci, 0, &ehci->regs->segment);
 #if 0
 // this is deeply broken on almost all architectures
 		if (!dma_set_mask(hcd->self.controller, DMA_64BIT_MASK))
@@ -531,7 +535,7 @@
 	// root hub will detect new devices (why?); NEC doesn't
 	ehci->command &= ~(CMD_LRESET|CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
 	ehci->command |= CMD_RUN;
-	writel (ehci->command, &ehci->regs->command);
+	ehci_writel(ehci, ehci->command, &ehci->regs->command);
 	dbg_cmd (ehci, "init", ehci->command);
 
 	/*
@@ -541,17 +545,18 @@
 	 * and there's no companion controller unless maybe for USB OTG.)
 	 */
 	hcd->state = HC_STATE_RUNNING;
-	writel (FLAG_CF, &ehci->regs->configured_flag);
-	readl (&ehci->regs->command);	/* unblock posted writes */
+	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
+	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */
 
-	temp = HC_VERSION(readl (&ehci->caps->hc_capbase));
+	temp = HC_VERSION(ehci_readl(ehci, &ehci->caps->hc_capbase));
 	ehci_info (ehci,
 		"USB %x.%x started, EHCI %x.%02x, driver %s%s\n",
 		((ehci->sbrn & 0xf0)>>4), (ehci->sbrn & 0x0f),
 		temp >> 8, temp & 0xff, DRIVER_VERSION,
 		ignore_oc ? ", overcurrent ignored" : "");
 
-	writel (INTR_MASK, &ehci->regs->intr_enable); /* Turn On Interrupts */
+	ehci_writel(ehci, INTR_MASK,
+		    &ehci->regs->intr_enable); /* Turn On Interrupts */
 
 	/* GRR this is run-once init(), being done every time the HC starts.
 	 * So long as they're part of class devices, we can't do it init()
@@ -572,7 +577,7 @@
 
 	spin_lock (&ehci->lock);
 
-	status = readl (&ehci->regs->status);
+	status = ehci_readl(ehci, &ehci->regs->status);
 
 	/* e.g. cardbus physical eject */
 	if (status == ~(u32) 0) {
@@ -587,8 +592,8 @@
 	}
 
 	/* clear (just) interrupts */
-	writel (status, &ehci->regs->status);
-	readl (&ehci->regs->command);	/* unblock posted write */
+	ehci_writel(ehci, status, &ehci->regs->status);
+	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted write */
 	bh = 0;
 
 #ifdef	EHCI_VERBOSE_DEBUG
@@ -619,11 +624,12 @@
 		unsigned	i = HCS_N_PORTS (ehci->hcs_params);
 
 		/* resume root hub? */
-		if (!(readl(&ehci->regs->command) & CMD_RUN))
+		if (!(ehci_readl(ehci, &ehci->regs->command) & CMD_RUN))
 			usb_hcd_resume_root_hub(hcd);
 
 		while (i--) {
-			int pstatus = readl (&ehci->regs->port_status [i]);
+			int pstatus = ehci_readl(ehci,
+						 &ehci->regs->port_status [i]);
 
 			if (pstatus & PORT_OWNER)
 				continue;
@@ -643,14 +649,15 @@
 	/* PCI errors [4.15.2.4] */
 	if (unlikely ((status & STS_FATAL) != 0)) {
 		/* bogus "fatal" IRQs appear on some chips... why?  */
-		status = readl (&ehci->regs->status);
-		dbg_cmd (ehci, "fatal", readl (&ehci->regs->command));
+		status = ehci_readl(ehci, &ehci->regs->status);
+		dbg_cmd (ehci, "fatal", ehci_readl(ehci,
+						   &ehci->regs->command));
 		dbg_status (ehci, "fatal", status);
 		if (status & STS_HALT) {
 			ehci_err (ehci, "fatal error\n");
 dead:
 			ehci_reset (ehci);
-			writel (0, &ehci->regs->configured_flag);
+			ehci_writel(ehci, 0, &ehci->regs->configured_flag);
 			/* generic layer kills/unlinks all urbs, then
 			 * uses ehci_stop to clean up the rest
 			 */
@@ -873,7 +880,8 @@
 static int ehci_get_frame (struct usb_hcd *hcd)
 {
 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
-	return (readl (&ehci->regs->frame_index) >> 3) % ehci->periodic_size;
+	return (ehci_readl(ehci, &ehci->regs->frame_index) >> 3) %
+		ehci->periodic_size;
 }
 
 /*-------------------------------------------------------------------------*/
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index bfe5f30..df00fcb 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -47,7 +47,7 @@
 		ehci_quiesce (ehci);
 		hcd->state = HC_STATE_QUIESCING;
 	}
-	ehci->command = readl (&ehci->regs->command);
+	ehci->command = ehci_readl(ehci, &ehci->regs->command);
 	if (ehci->reclaim)
 		ehci->reclaim_ready = 1;
 	ehci_work(ehci);
@@ -60,7 +60,7 @@
 	ehci->bus_suspended = 0;
 	while (port--) {
 		u32 __iomem	*reg = &ehci->regs->port_status [port];
-		u32		t1 = readl (reg) & ~PORT_RWC_BITS;
+		u32		t1 = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
 		u32		t2 = t1;
 
 		/* keep track of which ports we suspend */
@@ -79,7 +79,7 @@
 		if (t1 != t2) {
 			ehci_vdbg (ehci, "port %d, %08x -> %08x\n",
 				port + 1, t1, t2);
-			writel (t2, reg);
+			ehci_writel(ehci, t2, reg);
 		}
 	}
 
@@ -92,8 +92,8 @@
 	mask = INTR_MASK;
 	if (!device_may_wakeup(&hcd->self.root_hub->dev))
 		mask &= ~STS_PCD;
-	writel(mask, &ehci->regs->intr_enable);
-	readl(&ehci->regs->intr_enable);
+	ehci_writel(ehci, mask, &ehci->regs->intr_enable);
+	ehci_readl(ehci, &ehci->regs->intr_enable);
 
 	ehci->next_statechange = jiffies + msecs_to_jiffies(10);
 	spin_unlock_irq (&ehci->lock);
@@ -118,26 +118,26 @@
 	 * the last user of the controller, not reset/pm hardware keeping
 	 * state we gave to it.
 	 */
-	temp = readl(&ehci->regs->intr_enable);
+	temp = ehci_readl(ehci, &ehci->regs->intr_enable);
 	ehci_dbg(ehci, "resume root hub%s\n", temp ? "" : " after power loss");
 
 	/* at least some APM implementations will try to deliver
 	 * IRQs right away, so delay them until we're ready.
 	 */
-	writel(0, &ehci->regs->intr_enable);
+	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
 
 	/* re-init operational registers */
-	writel(0, &ehci->regs->segment);
-	writel(ehci->periodic_dma, &ehci->regs->frame_list);
-	writel((u32) ehci->async->qh_dma, &ehci->regs->async_next);
+	ehci_writel(ehci, 0, &ehci->regs->segment);
+	ehci_writel(ehci, ehci->periodic_dma, &ehci->regs->frame_list);
+	ehci_writel(ehci, (u32) ehci->async->qh_dma, &ehci->regs->async_next);
 
 	/* restore CMD_RUN, framelist size, and irq threshold */
-	writel (ehci->command, &ehci->regs->command);
+	ehci_writel(ehci, ehci->command, &ehci->regs->command);
 
 	/* manually resume the ports we suspended during bus_suspend() */
 	i = HCS_N_PORTS (ehci->hcs_params);
 	while (i--) {
-		temp = readl (&ehci->regs->port_status [i]);
+		temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
 		temp &= ~(PORT_RWC_BITS
 			| PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E);
 		if (test_bit(i, &ehci->bus_suspended) &&
@@ -145,20 +145,20 @@
 			ehci->reset_done [i] = jiffies + msecs_to_jiffies (20);
 			temp |= PORT_RESUME;
 		}
-		writel (temp, &ehci->regs->port_status [i]);
+		ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
 	}
 	i = HCS_N_PORTS (ehci->hcs_params);
 	mdelay (20);
 	while (i--) {
-		temp = readl (&ehci->regs->port_status [i]);
+		temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
 		if (test_bit(i, &ehci->bus_suspended) &&
 				(temp & PORT_SUSPEND)) {
 			temp &= ~(PORT_RWC_BITS | PORT_RESUME);
-			writel (temp, &ehci->regs->port_status [i]);
+			ehci_writel(ehci, temp, &ehci->regs->port_status [i]);
 			ehci_vdbg (ehci, "resumed port %d\n", i + 1);
 		}
 	}
-	(void) readl (&ehci->regs->command);
+	(void) ehci_readl(ehci, &ehci->regs->command);
 
 	/* maybe re-activate the schedule(s) */
 	temp = 0;
@@ -168,14 +168,14 @@
 		temp |= CMD_PSE;
 	if (temp) {
 		ehci->command |= temp;
-		writel (ehci->command, &ehci->regs->command);
+		ehci_writel(ehci, ehci->command, &ehci->regs->command);
 	}
 
 	ehci->next_statechange = jiffies + msecs_to_jiffies(5);
 	hcd->state = HC_STATE_RUNNING;
 
 	/* Now we can safely re-enable irqs */
-	writel(INTR_MASK, &ehci->regs->intr_enable);
+	ehci_writel(ehci, INTR_MASK, &ehci->regs->intr_enable);
 
 	spin_unlock_irq (&ehci->lock);
 	return 0;
@@ -217,7 +217,8 @@
 		// what happens if HCS_N_CC(params) == 0 ?
 		port_status |= PORT_OWNER;
 		port_status &= ~PORT_RWC_BITS;
-		writel (port_status, &ehci->regs->port_status [index]);
+		ehci_writel(ehci, port_status,
+			    &ehci->regs->port_status [index]);
 
 	} else
 		ehci_dbg (ehci, "port %d high speed\n", index + 1);
@@ -268,13 +269,14 @@
 	/* port N changes (bit N)? */
 	spin_lock_irqsave (&ehci->lock, flags);
 	for (i = 0; i < ports; i++) {
-		temp = readl (&ehci->regs->port_status [i]);
+		temp = ehci_readl(ehci, &ehci->regs->port_status [i]);
 		if (temp & PORT_OWNER) {
 			/* don't report this in GetPortStatus */
 			if (temp & PORT_CSC) {
 				temp &= ~PORT_RWC_BITS;
 				temp |= PORT_CSC;
-				writel (temp, &ehci->regs->port_status [i]);
+				ehci_writel(ehci, temp,
+					    &ehci->regs->port_status [i]);
 			}
 			continue;
 		}
@@ -373,18 +375,18 @@
 		if (!wIndex || wIndex > ports)
 			goto error;
 		wIndex--;
-		temp = readl (&ehci->regs->port_status [wIndex]);
+		temp = ehci_readl(ehci, &ehci->regs->port_status [wIndex]);
 		if (temp & PORT_OWNER)
 			break;
 
 		switch (wValue) {
 		case USB_PORT_FEAT_ENABLE:
-			writel (temp & ~PORT_PE,
-				&ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, temp & ~PORT_PE,
+				    &ehci->regs->port_status [wIndex]);
 			break;
 		case USB_PORT_FEAT_C_ENABLE:
-			writel((temp & ~PORT_RWC_BITS) | PORT_PEC,
-				&ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, (temp & ~PORT_RWC_BITS) | PORT_PEC,
+				    &ehci->regs->port_status [wIndex]);
 			break;
 		case USB_PORT_FEAT_SUSPEND:
 			if (temp & PORT_RESET)
@@ -396,8 +398,8 @@
 					goto error;
 				/* resume signaling for 20 msec */
 				temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
-				writel (temp | PORT_RESUME,
-					&ehci->regs->port_status [wIndex]);
+				ehci_writel(ehci, temp | PORT_RESUME,
+					    &ehci->regs->port_status [wIndex]);
 				ehci->reset_done [wIndex] = jiffies
 						+ msecs_to_jiffies (20);
 			}
@@ -407,16 +409,17 @@
 			break;
 		case USB_PORT_FEAT_POWER:
 			if (HCS_PPC (ehci->hcs_params))
-				writel (temp & ~(PORT_RWC_BITS | PORT_POWER),
-					&ehci->regs->port_status [wIndex]);
+				ehci_writel(ehci,
+					  temp & ~(PORT_RWC_BITS | PORT_POWER),
+					  &ehci->regs->port_status [wIndex]);
 			break;
 		case USB_PORT_FEAT_C_CONNECTION:
-			writel((temp & ~PORT_RWC_BITS) | PORT_CSC,
-				&ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, (temp & ~PORT_RWC_BITS) | PORT_CSC,
+				    &ehci->regs->port_status [wIndex]);
 			break;
 		case USB_PORT_FEAT_C_OVER_CURRENT:
-			writel((temp & ~PORT_RWC_BITS) | PORT_OCC,
-				&ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, (temp & ~PORT_RWC_BITS) | PORT_OCC,
+				    &ehci->regs->port_status [wIndex]);
 			break;
 		case USB_PORT_FEAT_C_RESET:
 			/* GetPortStatus clears reset */
@@ -424,7 +427,7 @@
 		default:
 			goto error;
 		}
-		readl (&ehci->regs->command);	/* unblock posted write */
+		ehci_readl(ehci, &ehci->regs->command);	/* unblock posted write */
 		break;
 	case GetHubDescriptor:
 		ehci_hub_descriptor (ehci, (struct usb_hub_descriptor *)
@@ -440,7 +443,7 @@
 			goto error;
 		wIndex--;
 		status = 0;
-		temp = readl (&ehci->regs->port_status [wIndex]);
+		temp = ehci_readl(ehci, &ehci->regs->port_status [wIndex]);
 
 		// wPortChange bits
 		if (temp & PORT_CSC)
@@ -458,12 +461,14 @@
 			ehci->reset_done [wIndex] = 0;
 
 			/* stop resume signaling */
-			temp = readl (&ehci->regs->port_status [wIndex]);
-			writel (temp & ~(PORT_RWC_BITS | PORT_RESUME),
-				&ehci->regs->port_status [wIndex]);
-			retval = handshake (
-					&ehci->regs->port_status [wIndex],
-					PORT_RESUME, 0, 2000 /* 2msec */);
+			temp = ehci_readl(ehci,
+					  &ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci,
+				    temp & ~(PORT_RWC_BITS | PORT_RESUME),
+				    &ehci->regs->port_status [wIndex]);
+			retval = handshake(ehci,
+					   &ehci->regs->port_status [wIndex],
+					   PORT_RESUME, 0, 2000 /* 2msec */);
 			if (retval != 0) {
 				ehci_err (ehci, "port %d resume error %d\n",
 					wIndex + 1, retval);
@@ -480,13 +485,13 @@
 			ehci->reset_done [wIndex] = 0;
 
 			/* force reset to complete */
-			writel (temp & ~(PORT_RWC_BITS | PORT_RESET),
-					&ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, temp & ~(PORT_RWC_BITS | PORT_RESET),
+				    &ehci->regs->port_status [wIndex]);
 			/* REVISIT:  some hardware needs 550+ usec to clear
 			 * this bit; seems too long to spin routinely...
 			 */
-			retval = handshake (
-					&ehci->regs->port_status [wIndex],
+			retval = handshake(ehci,
+					   &ehci->regs->port_status [wIndex],
 					PORT_RESET, 0, 750);
 			if (retval != 0) {
 				ehci_err (ehci, "port %d reset error %d\n",
@@ -496,7 +501,8 @@
 
 			/* see what we found out */
 			temp = check_reset_complete (ehci, wIndex,
-				readl (&ehci->regs->port_status [wIndex]));
+				ehci_readl(ehci,
+					   &ehci->regs->port_status [wIndex]));
 		}
 
 		// don't show wPortStatus if it's owned by a companion hc
@@ -541,7 +547,7 @@
 		if (!wIndex || wIndex > ports)
 			goto error;
 		wIndex--;
-		temp = readl (&ehci->regs->port_status [wIndex]);
+		temp = ehci_readl(ehci, &ehci->regs->port_status [wIndex]);
 		if (temp & PORT_OWNER)
 			break;
 
@@ -555,13 +561,13 @@
 				goto error;
 			if (device_may_wakeup(&hcd->self.root_hub->dev))
 				temp |= PORT_WAKE_BITS;
-			writel (temp | PORT_SUSPEND,
-				&ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, temp | PORT_SUSPEND,
+				    &ehci->regs->port_status [wIndex]);
 			break;
 		case USB_PORT_FEAT_POWER:
 			if (HCS_PPC (ehci->hcs_params))
-				writel (temp | PORT_POWER,
-					&ehci->regs->port_status [wIndex]);
+				ehci_writel(ehci, temp | PORT_POWER,
+					    &ehci->regs->port_status [wIndex]);
 			break;
 		case USB_PORT_FEAT_RESET:
 			if (temp & PORT_RESUME)
@@ -589,7 +595,8 @@
 				ehci->reset_done [wIndex] = jiffies
 						+ msecs_to_jiffies (50);
 			}
-			writel (temp, &ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, temp,
+				    &ehci->regs->port_status [wIndex]);
 			break;
 
 		/* For downstream facing ports (these):  one hub port is put
@@ -604,13 +611,14 @@
 			ehci_quiesce(ehci);
 			ehci_halt(ehci);
 			temp |= selector << 16;
-			writel (temp, &ehci->regs->port_status [wIndex]);
+			ehci_writel(ehci, temp,
+				    &ehci->regs->port_status [wIndex]);
 			break;
 
 		default:
 			goto error;
 		}
-		readl (&ehci->regs->command);	/* unblock posted writes */
+		ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */
 		break;
 
 	default:
diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index 4bc7970..12edc72 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -38,7 +38,7 @@
 		if ((temp & (3 << 13)) == (1 << 13)) {
 			temp &= 0x1fff;
 			ehci->debug = ehci_to_hcd(ehci)->regs + temp;
-			temp = readl(&ehci->debug->control);
+			temp = ehci_readl(ehci, &ehci->debug->control);
 			ehci_info(ehci, "debug port %d%s\n",
 				HCS_DEBUG_PORT(ehci->hcs_params),
 				(temp & DBGP_ENABLED)
@@ -71,8 +71,24 @@
 	u32			temp;
 	int			retval;
 
+	switch (pdev->vendor) {
+	case PCI_VENDOR_ID_TOSHIBA_2:
+		/* celleb's companion chip */
+		if (pdev->device == 0x01b5) {
+#ifdef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
+			ehci->big_endian_mmio = 1;
+#else
+			ehci_warn(ehci,
+				  "unsupported big endian Toshiba quirk\n");
+#endif
+		}
+		break;
+	}
+
 	ehci->caps = hcd->regs;
-	ehci->regs = hcd->regs + HC_LENGTH(readl(&ehci->caps->hc_capbase));
+	ehci->regs = hcd->regs +
+		HC_LENGTH(ehci_readl(ehci, &ehci->caps->hc_capbase));
+
 	dbg_hcs_params(ehci, "reset");
 	dbg_hcc_params(ehci, "reset");
 
@@ -101,7 +117,7 @@
 	}
 
 	/* cache this readonly data; minimize chip reads */
-	ehci->hcs_params = readl(&ehci->caps->hcs_params);
+	ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
 
 	retval = ehci_halt(ehci);
 	if (retval)
@@ -235,8 +251,8 @@
 		rc = -EINVAL;
 		goto bail;
 	}
-	writel (0, &ehci->regs->intr_enable);
-	(void)readl(&ehci->regs->intr_enable);
+	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
+	(void)ehci_readl(ehci, &ehci->regs->intr_enable);
 
 	/* make sure snapshot being resumed re-enumerates everything */
 	if (message.event == PM_EVENT_PRETHAW) {
@@ -270,13 +286,13 @@
 	/* If CF is still set, we maintained PCI Vaux power.
 	 * Just undo the effect of ehci_pci_suspend().
 	 */
-	if (readl(&ehci->regs->configured_flag) == FLAG_CF) {
+	if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF) {
 		int	mask = INTR_MASK;
 
 		if (!device_may_wakeup(&hcd->self.root_hub->dev))
 			mask &= ~STS_PCD;
-		writel(mask, &ehci->regs->intr_enable);
-		readl(&ehci->regs->intr_enable);
+		ehci_writel(ehci, mask, &ehci->regs->intr_enable);
+		ehci_readl(ehci, &ehci->regs->intr_enable);
 		return 0;
 	}
 
@@ -300,9 +316,9 @@
 	/* here we "know" root ports should always stay powered */
 	ehci_port_power(ehci, 1);
 
-	writel(ehci->command, &ehci->regs->command);
-	writel(FLAG_CF, &ehci->regs->configured_flag);
-	readl(&ehci->regs->command);	/* unblock posted writes */
+	ehci_writel(ehci, ehci->command, &ehci->regs->command);
+	ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
+	ehci_readl(ehci, &ehci->regs->command);	/* unblock posted writes */
 
 	hcd->state = HC_STATE_SUSPENDED;
 	return 0;
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 62e46dc..e7fbbd0 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -789,13 +789,14 @@
 	head = ehci->async;
 	timer_action_done (ehci, TIMER_ASYNC_OFF);
 	if (!head->qh_next.qh) {
-		u32	cmd = readl (&ehci->regs->command);
+		u32	cmd = ehci_readl(ehci, &ehci->regs->command);
 
 		if (!(cmd & CMD_ASE)) {
 			/* in case a clear of CMD_ASE didn't take yet */
-			(void) handshake (&ehci->regs->status, STS_ASS, 0, 150);
+			(void)handshake(ehci, &ehci->regs->status,
+					STS_ASS, 0, 150);
 			cmd |= CMD_ASE | CMD_RUN;
-			writel (cmd, &ehci->regs->command);
+			ehci_writel(ehci, cmd, &ehci->regs->command);
 			ehci_to_hcd(ehci)->state = HC_STATE_RUNNING;
 			/* posted write need not be known to HC yet ... */
 		}
@@ -1007,7 +1008,7 @@
 
 static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
 {
-	int		cmd = readl (&ehci->regs->command);
+	int		cmd = ehci_readl(ehci, &ehci->regs->command);
 	struct ehci_qh	*prev;
 
 #ifdef DEBUG
@@ -1025,7 +1026,8 @@
 		if (ehci_to_hcd(ehci)->state != HC_STATE_HALT
 				&& !ehci->reclaim) {
 			/* ... and CMD_IAAD clear */
-			writel (cmd & ~CMD_ASE, &ehci->regs->command);
+			ehci_writel(ehci, cmd & ~CMD_ASE,
+				    &ehci->regs->command);
 			wmb ();
 			// handshake later, if we need to
 			timer_action_done (ehci, TIMER_ASYNC_OFF);
@@ -1054,8 +1056,8 @@
 
 	ehci->reclaim_ready = 0;
 	cmd |= CMD_IAAD;
-	writel (cmd, &ehci->regs->command);
-	(void) readl (&ehci->regs->command);
+	ehci_writel(ehci, cmd, &ehci->regs->command);
+	(void)ehci_readl(ehci, &ehci->regs->command);
 	timer_action (ehci, TIMER_IAA_WATCHDOG);
 }
 
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 65c402a..7b5ae71 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -433,20 +433,20 @@
 	/* did clearing PSE did take effect yet?
 	 * takes effect only at frame boundaries...
 	 */
-	status = handshake (&ehci->regs->status, STS_PSS, 0, 9 * 125);
+	status = handshake(ehci, &ehci->regs->status, STS_PSS, 0, 9 * 125);
 	if (status != 0) {
 		ehci_to_hcd(ehci)->state = HC_STATE_HALT;
 		return status;
 	}
 
-	cmd = readl (&ehci->regs->command) | CMD_PSE;
-	writel (cmd, &ehci->regs->command);
+	cmd = ehci_readl(ehci, &ehci->regs->command) | CMD_PSE;
+	ehci_writel(ehci, cmd, &ehci->regs->command);
 	/* posted write ... PSS happens later */
 	ehci_to_hcd(ehci)->state = HC_STATE_RUNNING;
 
 	/* make sure ehci_work scans these */
-	ehci->next_uframe = readl (&ehci->regs->frame_index)
-				% (ehci->periodic_size << 3);
+	ehci->next_uframe = ehci_readl(ehci, &ehci->regs->frame_index)
+		% (ehci->periodic_size << 3);
 	return 0;
 }
 
@@ -458,14 +458,14 @@
 	/* did setting PSE not take effect yet?
 	 * takes effect only at frame boundaries...
 	 */
-	status = handshake (&ehci->regs->status, STS_PSS, STS_PSS, 9 * 125);
+	status = handshake(ehci, &ehci->regs->status, STS_PSS, STS_PSS, 9 * 125);
 	if (status != 0) {
 		ehci_to_hcd(ehci)->state = HC_STATE_HALT;
 		return status;
 	}
 
-	cmd = readl (&ehci->regs->command) & ~CMD_PSE;
-	writel (cmd, &ehci->regs->command);
+	cmd = ehci_readl(ehci, &ehci->regs->command) & ~CMD_PSE;
+	ehci_writel(ehci, cmd, &ehci->regs->command);
 	/* posted write ... */
 
 	ehci->next_uframe = -1;
@@ -1336,7 +1336,7 @@
 		goto fail;
 	}
 
-	now = readl (&ehci->regs->frame_index) % mod;
+	now = ehci_readl(ehci, &ehci->regs->frame_index) % mod;
 
 	/* when's the last uframe this urb could start? */
 	max = now + mod;
@@ -2088,7 +2088,7 @@
 	 */
 	now_uframe = ehci->next_uframe;
 	if (HC_IS_RUNNING (ehci_to_hcd(ehci)->state))
-		clock = readl (&ehci->regs->frame_index);
+		clock = ehci_readl(ehci, &ehci->regs->frame_index);
 	else
 		clock = now_uframe + mod - 1;
 	clock %= mod;
@@ -2213,7 +2213,7 @@
 			if (!HC_IS_RUNNING (ehci_to_hcd(ehci)->state))
 				break;
 			ehci->next_uframe = now_uframe;
-			now = readl (&ehci->regs->frame_index) % mod;
+			now = ehci_readl(ehci, &ehci->regs->frame_index) % mod;
 			if (now_uframe == now)
 				break;
 
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 74dbc6c..5f28b74 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -92,6 +92,7 @@
 	unsigned		is_tdi_rh_tt:1;	/* TDI roothub with TT */
 	unsigned		no_selective_suspend:1;
 	unsigned		has_fsl_port_bug:1; /* FreeScale */
+	unsigned		big_endian_mmio:1;
 
 	u8			sbrn;		/* packed release number */
 
@@ -651,6 +652,37 @@
 #define	ehci_has_fsl_portno_bug(e)		(0)
 #endif
 
+/*
+ * While most USB host controllers implement their registers in
+ * little-endian format, a minority (celleb companion chip) implement
+ * them in big endian format.
+ *
+ * This attempts to support either format at compile time without a
+ * runtime penalty, or both formats with the additional overhead
+ * of checking a flag bit.
+ */
+
+#ifdef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
+#define ehci_big_endian_mmio(e)		((e)->big_endian_mmio)
+#else
+#define ehci_big_endian_mmio(e)		0
+#endif
+
+static inline unsigned int ehci_readl (const struct ehci_hcd *ehci,
+				       __u32 __iomem * regs)
+{
+	return ehci_big_endian_mmio(ehci) ?
+		readl_be((__force u32 *)regs) :
+		readl((__force u32 *)regs);
+}
+
+static inline void ehci_writel (const struct ehci_hcd *ehci,
+				const unsigned int val, __u32 __iomem *regs)
+{
+	ehci_big_endian_mmio(ehci) ?
+		writel_be(val, (__force u32 *)regs) :
+		writel(val, (__force u32 *)regs);
+}
 
 /*-------------------------------------------------------------------------*/