--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1259,7 +1259,7 @@ static void hub_quiesce(struct usb_hub *
 	if (type != HUB_SUSPEND) {
 		/* Disconnect all the children */
 		for (i = 0; i < hdev->maxchild; ++i) {
-			if (hub->ports[i]->child)
+			if (hub->ports[i] && hub->ports[i]->child)
 				usb_disconnect(&hub->ports[i]->child);
 		}
 	}
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -193,6 +193,7 @@ exit:
 void usb_hub_remove_port_device(struct usb_hub *hub,
 				       int port1)
 {
-	device_unregister(&hub->ports[port1 - 1]->dev);
+	if (hub->ports[port1 - 1])
+		device_unregister(&hub->ports[port1 - 1]->dev);
 }
 
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -28,7 +28,11 @@ config USB_XHCI_HCD
 if USB_XHCI_HCD
 
 config USB_XHCI_PLATFORM
-	tristate
+	bool "xHCI platform"
+
+config USB_MT7621_XHCI_PLATFORM
+	bool "MTK MT7621 xHCI"
+	depends on USB_XHCI_PLATFORM
 
 config USB_XHCI_HCD_DEBUGGING
 	bool "Debugging for the xHCI host controller"
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -13,15 +13,23 @@ fhci-$(CONFIG_FHCI_DEBUG) += fhci-dbg.o
 
 xhci-hcd-y := xhci.o xhci-mem.o
 xhci-hcd-y += xhci-ring.o xhci-hub.o xhci-dbg.o
+ifndef CONFIG_USB_MT7621_XHCI_PLATFORM
 xhci-hcd-$(CONFIG_PCI)	+= xhci-pci.o
+endif
+
+ifdef CONFIG_USB_MT7621_XHCI_PLATFORM
+xhci-hcd-y += mtk-phy.o xhci-mtk-scheduler.o xhci-mtk-power.o xhci-mtk.o mtk-phy-7621.o mtk-phy-ahb.o
+endif
 
 ifneq ($(CONFIG_USB_XHCI_PLATFORM), )
-	xhci-hcd-y		+= xhci-plat.o
+xhci-hcd-y		+= xhci-plat.o
 endif
 
 obj-$(CONFIG_USB_WHCI_HCD)	+= whci/
 
+ifndef CONFIG_USB_MT7621_XHCI_PLATFORM
 obj-$(CONFIG_PCI)		+= pci-quirks.o
+endif
 
 obj-$(CONFIG_USB_EHCI_HCD)	+= ehci-hcd.o
 obj-$(CONFIG_USB_EHCI_PCI)	+= ehci-pci.o
--- a/drivers/usb/host/pci-quirks.h
+++ b/drivers/usb/host/pci-quirks.h
@@ -1,7 +1,7 @@
 #ifndef __LINUX_USB_PCI_QUIRKS_H
 #define __LINUX_USB_PCI_QUIRKS_H
 
-#ifdef CONFIG_PCI
+#if defined (CONFIG_PCI) && !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 void uhci_reset_hc(struct pci_dev *pdev, unsigned long base);
 int uhci_check_and_reset_hc(struct pci_dev *pdev, unsigned long base);
 #endif  /* CONFIG_PCI */
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -30,6 +30,16 @@
 
 #include "xhci.h"
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+#include <asm/uaccess.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include "mtk-phy.h"
+#include "xhci-mtk-scheduler.h"
+#include "xhci-mtk-power.h"
+#include "xhci-mtk.h"
+#endif
+
 #define DRIVER_AUTHOR "Sarah Sharp"
 #define DRIVER_DESC "'eXtensible' Host Controller (xHC) Driver"
 
@@ -38,6 +48,18 @@ static int link_quirk;
 module_param(link_quirk, int, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(link_quirk, "Don't clear the chain bit on a link TRB");
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+long xhci_mtk_test_unlock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+static struct file_operations xhci_mtk_test_fops = {
+    .owner =		THIS_MODULE,
+    .read =		xhci_mtk_test_read,
+    .write =		xhci_mtk_test_write,
+    .unlocked_ioctl =	xhci_mtk_test_unlock_ioctl,
+    .open =		xhci_mtk_test_open,
+    .release =		xhci_mtk_test_release,
+};
+#endif
+
 /* TODO: copied from ehci-hcd.c - can this be refactored? */
 /*
  * xhci_handshake - spin reading hc until handshake completes or fails
@@ -189,7 +211,7 @@ int xhci_reset(struct xhci_hcd *xhci)
 	return ret;
 }
 
-#ifdef CONFIG_PCI
+#if defined (CONFIG_PCI) && !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 static int xhci_free_msi(struct xhci_hcd *xhci)
 {
 	int i;
@@ -386,6 +408,7 @@ static int xhci_try_enable_msi(struct us
 		return ret;
 	}
 	hcd->irq = pdev->irq;
+
 	return 0;
 }
 
@@ -427,6 +450,11 @@ static void compliance_mode_recovery(uns
 			xhci_dbg(xhci, "Attempting compliance mode recovery\n");
 			hcd = xhci->shared_hcd;
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+			temp |= (1 << 31);
+			xhci_writel(xhci, temp, xhci->usb3_ports[i]);
+#endif
+
 			if (hcd->state == HC_STATE_SUSPENDED)
 				usb_hcd_resume_root_hub(hcd);
 
@@ -475,6 +503,9 @@ bool xhci_compliance_mode_recovery_timer
 {
 	const char *dmi_product_name, *dmi_sys_vendor;
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	return true;
+#endif
 	dmi_product_name = dmi_get_system_info(DMI_PRODUCT_NAME);
 	dmi_sys_vendor = dmi_get_system_info(DMI_SYS_VENDOR);
 	if (!dmi_product_name || !dmi_sys_vendor)
@@ -518,6 +549,10 @@ int xhci_init(struct usb_hcd *hcd)
 	} else {
 		xhci_dbg(xhci, "xHCI doesn't need link TRB QUIRK\n");
 	}
+
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	mtk_xhci_scheduler_init();
+#endif
 	retval = xhci_mem_init(xhci, GFP_KERNEL);
 	xhci_dbg(xhci, "Finished xhci_init\n");
 
@@ -661,7 +696,11 @@ int xhci_run(struct usb_hcd *hcd)
 	xhci_dbg(xhci, "// Set the interrupt modulation register\n");
 	temp = xhci_readl(xhci, &xhci->ir_set->irq_control);
 	temp &= ~ER_IRQ_INTERVAL_MASK;
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	temp |= (u32) 16;
+#else
 	temp |= (u32) 160;
+#endif
 	xhci_writel(xhci, temp, &xhci->ir_set->irq_control);
 
 	/* Set the HCD state before we enable the irqs */
@@ -682,6 +721,9 @@ int xhci_run(struct usb_hcd *hcd)
 		xhci_queue_vendor_command(xhci, 0, 0, 0,
 				TRB_TYPE(TRB_NEC_GET_FW));
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	enableXhciAllPortPower(xhci);
+#endif
 	xhci_dbg(xhci, "Finished xhci_run for USB2 roothub\n");
 	return 0;
 }
@@ -999,7 +1041,6 @@ int xhci_resume(struct xhci_hcd *xhci, b
 
 	/* If restore operation fails, re-initialize the HC during resume */
 	if ((temp & STS_SRE) || hibernated) {
-
 		if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
 				!(xhci_all_ports_seen_u0(xhci))) {
 			del_timer_sync(&xhci->comp_mode_recovery_timer);
@@ -1583,6 +1624,13 @@ int xhci_drop_endpoint(struct usb_hcd *h
 	u32 drop_flag;
 	u32 new_add_flags, new_drop_flags, new_slot_info;
 	int ret;
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+#if MTK_SCH_NEW
+	struct sch_ep *sch_ep = NULL;
+	int isTT;
+	int ep_type;
+#endif
+#endif
 
 	ret = xhci_check_args(hcd, udev, ep, 1, true, __func__);
 	if (ret <= 0)
@@ -1634,6 +1682,40 @@ int xhci_drop_endpoint(struct usb_hcd *h
 
 	xhci_endpoint_zero(xhci, xhci->devs[udev->slot_id], ep);
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+#if MTK_SCH_NEW
+	slot_ctx = xhci_get_slot_ctx(xhci, xhci->devs[udev->slot_id]->out_ctx);
+	if ((slot_ctx->tt_info & 0xff) > 0) {
+		isTT = 1;
+	}
+	else {
+		isTT = 0;
+	}
+	if (usb_endpoint_xfer_int(&ep->desc)) {
+		ep_type = USB_EP_INT;
+	}
+	else if (usb_endpoint_xfer_isoc(&ep->desc)) {
+		ep_type = USB_EP_ISOC;
+	}
+	else if (usb_endpoint_xfer_bulk(&ep->desc)) {
+		ep_type = USB_EP_BULK;
+	}
+	else
+		ep_type = USB_EP_CONTROL;
+
+	sch_ep = mtk_xhci_scheduler_remove_ep(udev->speed, usb_endpoint_dir_in(&ep->desc)
+		, isTT, ep_type, (mtk_u32 *)ep);
+	if (sch_ep != NULL) {
+		kfree(sch_ep);
+	}
+	else {
+		xhci_dbg(xhci, "[MTK]Doesn't find ep_sch instance when removing endpoint\n");
+	}
+#else
+	mtk_xhci_scheduler_remove_ep(xhci, udev, ep);
+#endif
+#endif
+
 	xhci_dbg(xhci, "drop ep 0x%x, slot id %d, new drop flags = %#x, new add flags = %#x, new slot info = %#x\n",
 			(unsigned int) ep->desc.bEndpointAddress,
 			udev->slot_id,
@@ -1669,6 +1751,18 @@ int xhci_add_endpoint(struct usb_hcd *hc
 	u32 new_add_flags, new_drop_flags, new_slot_info;
 	struct xhci_virt_device *virt_dev;
 	int ret = 0;
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	struct xhci_ep_ctx *in_ep_ctx;
+#if MTK_SCH_NEW
+	struct sch_ep *sch_ep;
+	int isTT;
+	int ep_type;
+	int maxp = 0;
+	int burst = 0;
+	int mult = 0;
+	int interval;
+#endif
+#endif
 
 	ret = xhci_check_args(hcd, udev, ep, 1, true, __func__);
 	if (ret <= 0) {
@@ -1731,6 +1825,56 @@ int xhci_add_endpoint(struct usb_hcd *hc
 		return -ENOMEM;
 	}
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	in_ep_ctx = xhci_get_ep_ctx(xhci, in_ctx, ep_index);
+#if MTK_SCH_NEW
+	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->out_ctx);
+	if ((slot_ctx->tt_info & 0xff) > 0) {
+		isTT = 1;
+	}
+	else {
+		isTT = 0;
+	}
+	if (usb_endpoint_xfer_int(&ep->desc)) {
+		ep_type = USB_EP_INT;
+	}
+	else if (usb_endpoint_xfer_isoc(&ep->desc)) {
+		ep_type = USB_EP_ISOC;
+	}
+	else if (usb_endpoint_xfer_bulk(&ep->desc)) {
+		ep_type = USB_EP_BULK;
+	}
+	else
+		ep_type = USB_EP_CONTROL;
+
+	if (udev->speed == USB_SPEED_FULL || udev->speed == USB_SPEED_HIGH 
+		|| udev->speed == USB_SPEED_LOW) {
+		maxp = ep->desc.wMaxPacketSize & 0x7FF;
+		burst = ep->desc.wMaxPacketSize >> 11;
+		mult = 0;
+	}
+	else if (udev->speed == USB_SPEED_SUPER) {
+		maxp = ep->desc.wMaxPacketSize & 0x7FF;
+		burst = ep->ss_ep_comp.bMaxBurst;
+		mult = ep->ss_ep_comp.bmAttributes & 0x3;
+	}
+	interval = (1 << ((in_ep_ctx->ep_info >> 16) & 0xff));
+	sch_ep = kmalloc(sizeof(struct sch_ep), GFP_KERNEL);
+	if (mtk_xhci_scheduler_add_ep(udev->speed, usb_endpoint_dir_in(&ep->desc),
+		isTT, ep_type, maxp, interval, burst, mult, (mtk_u32 *)ep
+		, (mtk_u32 *)in_ep_ctx, sch_ep) != SCH_SUCCESS) {
+		xhci_err(xhci, "[MTK] not enough bandwidth\n");
+
+		return -ENOSPC;
+	}
+#else
+	if (mtk_xhci_scheduler_add_ep(xhci, udev, ep, in_ep_ctx) != SCH_SUCCESS) {
+		xhci_err(xhci, "[MTK] not enough bandwidth\n");
+
+		return -ENOSPC;
+	}
+#endif
+#endif
 	ctrl_ctx->add_flags |= cpu_to_le32(added_ctxs);
 	new_add_flags = le32_to_cpu(ctrl_ctx->add_flags);
 
@@ -2694,7 +2838,7 @@ int xhci_check_bandwidth(struct usb_hcd
 	if (ctrl_ctx->add_flags == cpu_to_le32(SLOT_FLAG) &&
 			ctrl_ctx->drop_flags == 0)
 		return 0;
-
+	
 	xhci_dbg(xhci, "New Input Control Context:\n");
 	slot_ctx = xhci_get_slot_ctx(xhci, virt_dev->in_ctx);
 	xhci_dbg_ctx(xhci, virt_dev->in_ctx,
@@ -4230,10 +4374,14 @@ static u16 xhci_call_host_update_timeout
 		u16 *timeout)
 {
 	if (state == USB3_LPM_U1) {
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 		if (xhci->quirks & XHCI_INTEL_HOST)
+#endif
 			return xhci_calculate_intel_u1_timeout(udev, desc);
 	} else {
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 		if (xhci->quirks & XHCI_INTEL_HOST)
+#endif
 			return xhci_calculate_intel_u2_timeout(udev, desc);
 	}
 
@@ -4659,7 +4807,9 @@ int xhci_gen_setup(struct usb_hcd *hcd,
 	/* Accept arbitrarily long scatter-gather lists */
 	hcd->self.sg_tablesize = ~0;
 	/* XHCI controllers don't stop the ep queue on short packets :| */
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 	hcd->self.no_stop_on_short = 1;
+#endif
 
 	if (usb_hcd_is_primary_hcd(hcd)) {
 		xhci = kzalloc(sizeof(struct xhci_hcd), GFP_KERNEL);
@@ -4728,6 +4878,10 @@ int xhci_gen_setup(struct usb_hcd *hcd,
 		goto error;
 	xhci_dbg(xhci, "Reset complete\n");
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	setInitialReg();
+#endif
+
 	temp = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
 	if (HCC_64BIT_ADDR(temp)) {
 		xhci_dbg(xhci, "Enabling 64-bit DMA addresses.\n");
@@ -4752,8 +4906,21 @@ MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_LICENSE("GPL");
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+static struct platform_device xhci_platform_dev = {
+	.name = "xhci-hcd",
+	.id   = -1,
+	.dev  = { 
+		.coherent_dma_mask = 0xffffffff,
+        },
+};
+#endif
+
 static int __init xhci_hcd_init(void)
 {
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	struct platform_device *pPlatformDev;
+#endif
 	int retval;
 
 	retval = xhci_register_pci();
@@ -4766,6 +4933,33 @@ static int __init xhci_hcd_init(void)
 		printk(KERN_DEBUG "Problem registering platform driver.");
 		goto unreg_pci;
 	}
+
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	retval = register_chrdev(XHCI_MTK_TEST_MAJOR, DEVICE_NAME, &xhci_mtk_test_fops);
+
+	u3phy_init();
+	if (u3phy_ops->u2_slew_rate_calibration) {
+                u3phy_ops->u2_slew_rate_calibration(u3phy);
+                u3phy_ops->u2_slew_rate_calibration(u3phy_p1);
+        }
+        else{
+                printk(KERN_ERR "WARN: PHY doesn't implement u2 slew rate calibration function\n");
+        }
+        u3phy_ops->init(u3phy);
+	reinitIP();
+
+	pPlatformDev = &xhci_platform_dev;
+	memset(pPlatformDev, 0, sizeof(struct platform_device));
+	pPlatformDev->name = "xhci-hcd";
+	pPlatformDev->id = -1;
+	pPlatformDev->dev.coherent_dma_mask = 0xffffffff;
+	pPlatformDev->dev.dma_mask = &pPlatformDev->dev.coherent_dma_mask;
+
+	retval = platform_device_register(&xhci_platform_dev);
+	if (retval < 0)
+		xhci_unregister_plat();
+#endif
+
 	/*
 	 * Check the compiler generated sizes of structures that must be laid
 	 * out in specific ways for hardware access.
@@ -4783,6 +4977,7 @@ static int __init xhci_hcd_init(void)
 	BUILD_BUG_ON(sizeof(struct xhci_intr_reg) != 8*32/8);
 	/* xhci_run_regs has eight fields and embeds 128 xhci_intr_regs */
 	BUILD_BUG_ON(sizeof(struct xhci_run_regs) != (8+8*128)*32/8);
+
 	return 0;
 unreg_pci:
 	xhci_unregister_pci();
--- a/drivers/usb/host/xhci-dbg.c
+++ b/drivers/usb/host/xhci-dbg.c
@@ -21,6 +21,9 @@
  */
 
 #include "xhci.h"
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+#include "xhci-mtk.h"
+#endif
 
 #define XHCI_INIT_VALUE 0x0
 
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -29,9 +29,24 @@
 #include <linux/usb/hcd.h>
 
 /* Code sharing between pci-quirks and xhci hcd */
-#include	"xhci-ext-caps.h"
+#include "xhci-ext-caps.h"
 #include "pci-quirks.h"
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+#define XHC_IRQ (22 + 8)
+#define XHC_IO_START 0x1E1C0000
+#define XHC_IO_LENGTH 0x10000
+/* mtk scheduler bitmasks */
+#define BPKTS(p)	((p) & 0x3f)
+#define BCSCOUNT(p)	(((p) & 0x7) << 8)
+#define BBM(p)		((p) << 11)
+#define BOFFSET(p)	((p) & 0x3fff)
+#define BREPEAT(p)	(((p) & 0x7fff) << 16)
+#endif
+
+
+
+
 /* xHCI PCI Configuration Registers */
 #define XHCI_SBRN_OFFSET	(0x60)
 
@@ -1536,8 +1551,12 @@ struct xhci_hcd {
 	/* Compliance Mode Recovery Data */
 	struct timer_list	comp_mode_recovery_timer;
 	u32			port_status_u0;
+#ifdef CONFIG_USB_MT7621_XHCI_PLATFORM
+#define COMP_MODE_RCVRY_MSECS 5000
+#else
 /* Compliance Mode Timer Triggered every 2 seconds */
 #define COMP_MODE_RCVRY_MSECS 2000
+#endif
 };
 
 /* convert between an HCD pointer and the corresponding EHCI_HCD */
@@ -1703,7 +1722,7 @@ void xhci_urb_free_priv(struct xhci_hcd
 void xhci_free_command(struct xhci_hcd *xhci,
 		struct xhci_command *command);
 
-#ifdef CONFIG_PCI
+#if defined (CONFIG_PCI) && !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 /* xHCI PCI glue */
 int xhci_register_pci(void);
 void xhci_unregister_pci(void);
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -65,6 +65,9 @@ static struct xhci_segment *xhci_segment
 
 static void xhci_segment_free(struct xhci_hcd *xhci, struct xhci_segment *seg)
 {
+	if (!seg)
+		return;
+
 	if (seg->trbs) {
 		dma_pool_free(xhci->segment_pool, seg->trbs, seg->dma);
 		seg->trbs = NULL;
@@ -1446,9 +1449,17 @@ int xhci_endpoint_init(struct xhci_hcd *
 			max_burst = (usb_endpoint_maxp(&ep->desc)
 				     & 0x1800) >> 11;
 		}
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+		if ((max_packet % 4 == 2) && (max_packet % 16 != 14) && (max_burst == 0) && usb_endpoint_dir_in(&ep->desc))
+		max_packet += 2;
+#endif
 		break;
 	case USB_SPEED_FULL:
 	case USB_SPEED_LOW:
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+		if ((max_packet % 4 == 2) && (max_packet % 16 != 14) && (max_burst == 0) && usb_endpoint_dir_in(&ep->desc))
+		max_packet += 2;
+#endif
 		break;
 	default:
 		BUG();
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -25,6 +25,13 @@ static void xhci_plat_quirks(struct devi
 	 * dev struct in order to setup MSI
 	 */
 	xhci->quirks |= XHCI_PLAT;
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	/* MTK host controller gives a spurious successful event after a 
+	 * short transfer. Ignore it.
+	 */
+	xhci->quirks |= XHCI_SPURIOUS_SUCCESS;
+	xhci->quirks |= XHCI_LPM_SUPPORT;
+#endif
 }
 
 /* called during probe() after chip reset completes */
@@ -96,20 +103,32 @@ static int xhci_plat_probe(struct platfo
 
 	driver = &xhci_plat_xhci_driver;
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	irq = XHC_IRQ;
+#else
 	irq = platform_get_irq(pdev, 0);
+#endif
+
 	if (irq < 0)
 		return -ENODEV;
 
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res)
 		return -ENODEV;
+#endif
 
 	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
 	if (!hcd)
 		return -ENOMEM;
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	hcd->rsrc_start = (uint32_t)XHC_IO_START;
+	hcd->rsrc_len = XHC_IO_LENGTH;
+#else
 	hcd->rsrc_start = res->start;
 	hcd->rsrc_len = resource_size(res);
+#endif
 
 	if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
 				driver->description)) {
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -236,7 +236,6 @@ static void inc_enq(struct xhci_hcd *xhc
 			 */
 			if (!chain && !more_trbs_coming)
 				break;
-
 			/* If we're not dealing with 0.95 hardware or
 			 * isoc rings on AMD 0.96 host,
 			 * carry over the chain bit of the previous TRB
@@ -273,16 +272,20 @@ static void inc_enq(struct xhci_hcd *xhc
 static inline int room_on_ring(struct xhci_hcd *xhci, struct xhci_ring *ring,
 		unsigned int num_trbs)
 {
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 	int num_trbs_in_deq_seg;
+#endif
 
 	if (ring->num_trbs_free < num_trbs)
 		return 0;
 
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 	if (ring->type != TYPE_COMMAND && ring->type != TYPE_EVENT) {
 		num_trbs_in_deq_seg = ring->dequeue - ring->deq_seg->trbs;
 		if (ring->num_trbs_free < num_trbs + num_trbs_in_deq_seg)
 			return 0;
 	}
+#endif
 
 	return 1;
 }
@@ -2910,6 +2913,7 @@ static int prepare_ring(struct xhci_hcd
 		next = ring->enqueue;
 
 		while (last_trb(xhci, ring, ring->enq_seg, next)) {
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 			/* If we're not dealing with 0.95 hardware or isoc rings
 			 * on AMD 0.96 host, clear the chain bit.
 			 */
@@ -2919,7 +2923,9 @@ static int prepare_ring(struct xhci_hcd
 				next->link.control &= cpu_to_le32(~TRB_CHAIN);
 			else
 				next->link.control |= cpu_to_le32(TRB_CHAIN);
-
+#else
+			next->link.control &= cpu_to_le32(~TRB_CHAIN);
+#endif
 			wmb();
 			next->link.control ^= cpu_to_le32(TRB_CYCLE);
 
@@ -3049,6 +3055,9 @@ static void giveback_first_trb(struct xh
 		start_trb->field[3] |= cpu_to_le32(start_cycle);
 	else
 		start_trb->field[3] &= cpu_to_le32(~TRB_CYCLE);
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	wmb();
+#endif
 	xhci_ring_ep_doorbell(xhci, slot_id, ep_index, stream_id);
 }
 
@@ -3108,6 +3117,29 @@ static u32 xhci_td_remainder(unsigned in
 		return (remainder >> 10) << 17;
 }
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+static u32 mtk_xhci_td_remainder(unsigned int td_transfer_size, unsigned int td_running_total, unsigned int maxp, unsigned trb_buffer_length)
+{
+	u32 max = 31;
+	int remainder, td_packet_count, packet_transferred;
+	
+	//0 for the last TRB
+	//FIXME: need to workaround if there is ZLP in this TD
+	if (td_running_total + trb_buffer_length == td_transfer_size)
+		return 0;
+	
+	//FIXME: need to take care of high-bandwidth (MAX_ESIT)
+	packet_transferred = (td_running_total /*+ trb_buffer_length*/) / maxp;
+	td_packet_count = DIV_ROUND_UP(td_transfer_size, maxp);
+	remainder = td_packet_count - packet_transferred;
+		
+	if (remainder > max)
+		return max << 17;
+	else
+		return remainder << 17;
+}
+#endif
+
 /*
  * For xHCI 1.0 host controllers, TD size is the number of max packet sized
  * packets remaining in the TD (*not* including this TRB).
@@ -3245,6 +3277,7 @@ static int queue_bulk_sg_tx(struct xhci_
 		}
 
 		/* Set the TRB length, TD size, and interrupter fields. */
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 		if (xhci->hci_version < 0x100) {
 			remainder = xhci_td_remainder(
 					urb->transfer_buffer_length -
@@ -3254,6 +3287,13 @@ static int queue_bulk_sg_tx(struct xhci_
 					trb_buff_len, total_packet_count, urb,
 					num_trbs - 1);
 		}
+#else
+		if (num_trbs > 1)
+			remainder = mtk_xhci_td_remainder(urb->transfer_buffer_length, 
+				running_total, urb->ep->desc.wMaxPacketSize, trb_buff_len);
+#endif
+
+	
 		length_field = TRB_LEN(trb_buff_len) |
 			remainder |
 			TRB_INTR_TARGET(0);
@@ -3316,6 +3356,9 @@ int xhci_queue_bulk_tx(struct xhci_hcd *
 	int running_total, trb_buff_len, ret;
 	unsigned int total_packet_count;
 	u64 addr;
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	int max_packet;
+#endif
 
 	if (urb->num_sgs)
 		return queue_bulk_sg_tx(xhci, mem_flags, urb, slot_id, ep_index);
@@ -3341,6 +3384,25 @@ int xhci_queue_bulk_tx(struct xhci_hcd *
 		running_total += TRB_MAX_BUFF_SIZE;
 	}
 	/* FIXME: this doesn't deal with URB_ZERO_PACKET - need one more */
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	switch(urb->dev->speed){
+		case USB_SPEED_SUPER:
+			max_packet = urb->ep->desc.wMaxPacketSize;
+			break;
+		case USB_SPEED_HIGH:
+		case USB_SPEED_FULL:
+		case USB_SPEED_LOW:
+		case USB_SPEED_WIRELESS:
+		case USB_SPEED_UNKNOWN:
+		default:
+			max_packet = urb->ep->desc.wMaxPacketSize & 0x7ff;
+			break;
+	}
+	if((urb->transfer_flags & URB_ZERO_PACKET) 
+		&& ((urb->transfer_buffer_length % max_packet) == 0)){
+		num_trbs++;
+	}
+#endif
 
 	ret = prepare_transfer(xhci, xhci->devs[slot_id],
 			ep_index, urb->stream_id,
@@ -3400,6 +3462,7 @@ int xhci_queue_bulk_tx(struct xhci_hcd *
 			field |= TRB_ISP;
 
 		/* Set the TRB length, TD size, and interrupter fields. */
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 		if (xhci->hci_version < 0x100) {
 			remainder = xhci_td_remainder(
 					urb->transfer_buffer_length -
@@ -3409,6 +3472,10 @@ int xhci_queue_bulk_tx(struct xhci_hcd *
 					trb_buff_len, total_packet_count, urb,
 					num_trbs - 1);
 		}
+#else
+		remainder = mtk_xhci_td_remainder(urb->transfer_buffer_length, running_total, max_packet, trb_buff_len);
+#endif
+
 		length_field = TRB_LEN(trb_buff_len) |
 			remainder |
 			TRB_INTR_TARGET(0);
@@ -3498,7 +3565,11 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *
 		field |= 0x1;
 
 	/* xHCI 1.0 6.4.1.2.1: Transfer Type field */
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	if (1) {
+#else
 	if (xhci->hci_version == 0x100) {
+#endif
 		if (urb->transfer_buffer_length > 0) {
 			if (setup->bRequestType & USB_DIR_IN)
 				field |= TRB_TX_TYPE(TRB_DATA_IN);
@@ -3522,7 +3593,12 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *
 		field = TRB_TYPE(TRB_DATA);
 
 	length_field = TRB_LEN(urb->transfer_buffer_length) |
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 		xhci_td_remainder(urb->transfer_buffer_length) |
+#else
+		//CC: MTK style, no scatter-gather for control transfer
+		0 |
+#endif
 		TRB_INTR_TARGET(0);
 	if (urb->transfer_buffer_length > 0) {
 		if (setup->bRequestType & USB_DIR_IN)
@@ -3533,7 +3609,7 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *
 				length_field,
 				field | ep_ring->cycle_state);
 	}
-
+	
 	/* Save the DMA address of the last TRB in the TD */
 	td->last_trb = ep_ring->enqueue;
 
@@ -3645,6 +3721,9 @@ static int xhci_queue_isoc_tx(struct xhc
 	u64 start_addr, addr;
 	int i, j;
 	bool more_trbs_coming;
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	int max_packet;
+#endif
 
 	ep_ring = xhci->devs[slot_id]->eps[ep_index].ring;
 
@@ -3658,6 +3737,21 @@ static int xhci_queue_isoc_tx(struct xhc
 	start_trb = &ep_ring->enqueue->generic;
 	start_cycle = ep_ring->cycle_state;
 
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+	switch(urb->dev->speed){
+		case USB_SPEED_SUPER:
+			max_packet = urb->ep->desc.wMaxPacketSize;
+			break;
+		case USB_SPEED_HIGH:
+		case USB_SPEED_FULL:
+		case USB_SPEED_LOW:
+		case USB_SPEED_WIRELESS:
+		case USB_SPEED_UNKNOWN:
+			max_packet = urb->ep->desc.wMaxPacketSize & 0x7ff;
+			break;
+	}
+#endif
+
 	urb_priv = urb->hcpriv;
 	/* Queue the first TRB, even if it's zero-length */
 	for (i = 0; i < num_tds; i++) {
@@ -3729,9 +3823,13 @@ static int xhci_queue_isoc_tx(struct xhc
 			} else {
 				td->last_trb = ep_ring->enqueue;
 				field |= TRB_IOC;
+#if defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
+				if (!(xhci->quirks & XHCI_AVOID_BEI)) {
+#else
 				if (xhci->hci_version == 0x100 &&
 						!(xhci->quirks &
 							XHCI_AVOID_BEI)) {
+#endif
 					/* Set BEI bit except for the last td */
 					if (i < num_tds - 1)
 						field |= TRB_BEI;
@@ -3746,6 +3844,7 @@ static int xhci_queue_isoc_tx(struct xhc
 				trb_buff_len = td_remain_len;
 
 			/* Set the TRB length, TD size, & interrupter fields. */
+#if !defined (CONFIG_USB_MT7621_XHCI_PLATFORM)
 			if (xhci->hci_version < 0x100) {
 				remainder = xhci_td_remainder(
 						td_len - running_total);
@@ -3755,6 +3854,10 @@ static int xhci_queue_isoc_tx(struct xhc
 						total_packet_count, urb,
 						(trbs_per_td - j - 1));
 			}
+#else
+			remainder = mtk_xhci_td_remainder(urb->transfer_buffer_length, running_total, max_packet, trb_buff_len);
+#endif
+
 			length_field = TRB_LEN(trb_buff_len) |
 				remainder |
 				TRB_INTR_TARGET(0);