diff --git a/drivers/usb/otg/Kconfig b/drivers/usb/otg/Kconfig
index 3b12895..299dfd2 100644
--- a/drivers/usb/otg/Kconfig
+++ b/drivers/usb/otg/Kconfig
@@ -67,4 +67,18 @@
 	 built-in with usb ip or which are autonomous and doesn't require any
 	 phy programming such as ISP1x04 etc.
 
+config USB_LANGWELL_OTG
+	tristate "Intel Langwell USB OTG dual-role support"
+	depends on USB && X86_MRST
+	select USB_OTG
+	select USB_OTG_UTILS
+	help
+	  Say Y here if you want to build Intel Langwell USB OTG
+	  transciever driver in kernel. This driver implements role
+	  switch between EHCI host driver and Langwell USB OTG
+	  client driver.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called langwell_otg.
+
 endif # USB || OTG
diff --git a/drivers/usb/otg/Makefile b/drivers/usb/otg/Makefile
index aeb49a8..b6609db 100644
--- a/drivers/usb/otg/Makefile
+++ b/drivers/usb/otg/Makefile
@@ -9,6 +9,7 @@
 obj-$(CONFIG_USB_GPIO_VBUS)	+= gpio_vbus.o
 obj-$(CONFIG_ISP1301_OMAP)	+= isp1301_omap.o
 obj-$(CONFIG_TWL4030_USB)	+= twl4030-usb.o
+obj-$(CONFIG_USB_LANGWELL_OTG)	+= langwell_otg.o
 obj-$(CONFIG_NOP_USB_XCEIV)	+= nop-usb-xceiv.o
 obj-$(CONFIG_USB_ULPI)		+= ulpi.o
 
diff --git a/drivers/usb/otg/langwell_otg.c b/drivers/usb/otg/langwell_otg.c
new file mode 100644
index 0000000..8791880
--- /dev/null
+++ b/drivers/usb/otg/langwell_otg.c
@@ -0,0 +1,2408 @@
+/*
+ * Intel Langwell USB OTG transceiver driver
+ * Copyright (C) 2008 - 2009, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+/* This driver helps to switch Langwell OTG controller function between host
+ * and peripheral. It works with EHCI driver and Langwell client controller
+ * driver together.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/moduleparam.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/hcd.h>
+#include <linux/notifier.h>
+#include <linux/delay.h>
+#include <asm/intel_scu_ipc.h>
+
+#include <linux/usb/langwell_otg.h>
+
+#define	DRIVER_DESC		"Intel Langwell USB OTG transceiver driver"
+#define	DRIVER_VERSION		"3.0.0.32L.0003"
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Henry Yuan <hang.yuan@intel.com>, Hao Wu <hao.wu@intel.com>");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+
+static const char driver_name[] = "langwell_otg";
+
+static int langwell_otg_probe(struct pci_dev *pdev,
+			const struct pci_device_id *id);
+static void langwell_otg_remove(struct pci_dev *pdev);
+static int langwell_otg_suspend(struct pci_dev *pdev, pm_message_t message);
+static int langwell_otg_resume(struct pci_dev *pdev);
+
+static int langwell_otg_set_host(struct otg_transceiver *otg,
+				struct usb_bus *host);
+static int langwell_otg_set_peripheral(struct otg_transceiver *otg,
+				struct usb_gadget *gadget);
+static int langwell_otg_start_srp(struct otg_transceiver *otg);
+
+static const struct pci_device_id pci_ids[] = {{
+	.class =        ((PCI_CLASS_SERIAL_USB << 8) | 0xfe),
+	.class_mask =   ~0,
+	.vendor =	0x8086,
+	.device =	0x0811,
+	.subvendor =	PCI_ANY_ID,
+	.subdevice =	PCI_ANY_ID,
+}, { /* end: all zeroes */ }
+};
+
+static struct pci_driver otg_pci_driver = {
+	.name =		(char *) driver_name,
+	.id_table =	pci_ids,
+
+	.probe =	langwell_otg_probe,
+	.remove =	langwell_otg_remove,
+
+	.suspend =	langwell_otg_suspend,
+	.resume =	langwell_otg_resume,
+};
+
+static const char *state_string(enum usb_otg_state state)
+{
+	switch (state) {
+	case OTG_STATE_A_IDLE:
+		return "a_idle";
+	case OTG_STATE_A_WAIT_VRISE:
+		return "a_wait_vrise";
+	case OTG_STATE_A_WAIT_BCON:
+		return "a_wait_bcon";
+	case OTG_STATE_A_HOST:
+		return "a_host";
+	case OTG_STATE_A_SUSPEND:
+		return "a_suspend";
+	case OTG_STATE_A_PERIPHERAL:
+		return "a_peripheral";
+	case OTG_STATE_A_WAIT_VFALL:
+		return "a_wait_vfall";
+	case OTG_STATE_A_VBUS_ERR:
+		return "a_vbus_err";
+	case OTG_STATE_B_IDLE:
+		return "b_idle";
+	case OTG_STATE_B_SRP_INIT:
+		return "b_srp_init";
+	case OTG_STATE_B_PERIPHERAL:
+		return "b_peripheral";
+	case OTG_STATE_B_WAIT_ACON:
+		return "b_wait_acon";
+	case OTG_STATE_B_HOST:
+		return "b_host";
+	default:
+		return "UNDEFINED";
+	}
+}
+
+/* HSM timers */
+static inline struct langwell_otg_timer *otg_timer_initializer
+(void (*function)(unsigned long), unsigned long expires, unsigned long data)
+{
+	struct langwell_otg_timer *timer;
+	timer = kmalloc(sizeof(struct langwell_otg_timer), GFP_KERNEL);
+	if (timer == NULL)
+		return timer;
+
+	timer->function = function;
+	timer->expires = expires;
+	timer->data = data;
+	return timer;
+}
+
+static struct langwell_otg_timer *a_wait_vrise_tmr, *a_aidl_bdis_tmr,
+	*b_se0_srp_tmr, *b_srp_init_tmr;
+
+static struct list_head active_timers;
+
+static struct langwell_otg *the_transceiver;
+
+/* host/client notify transceiver when event affects HNP state */
+void langwell_update_transceiver(void)
+{
+	struct langwell_otg *lnw = the_transceiver;
+
+	dev_dbg(lnw->dev, "transceiver is updated\n");
+
+	if (!lnw->qwork)
+		return ;
+
+	queue_work(lnw->qwork, &lnw->work);
+}
+EXPORT_SYMBOL(langwell_update_transceiver);
+
+static int langwell_otg_set_host(struct otg_transceiver *otg,
+					struct usb_bus *host)
+{
+	otg->host = host;
+
+	return 0;
+}
+
+static int langwell_otg_set_peripheral(struct otg_transceiver *otg,
+					struct usb_gadget *gadget)
+{
+	otg->gadget = gadget;
+
+	return 0;
+}
+
+static int langwell_otg_set_power(struct otg_transceiver *otg,
+				unsigned mA)
+{
+	return 0;
+}
+
+/* A-device drives vbus, controlled through PMIC CHRGCNTL register*/
+static int langwell_otg_set_vbus(struct otg_transceiver *otg, bool enabled)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	u8 r;
+
+	dev_dbg(lnw->dev, "%s <--- %s\n", __func__, enabled ? "on" : "off");
+
+	/* FIXME: surely we should cache this on the first read. If not use
+	   readv to avoid two transactions */
+	if (intel_scu_ipc_ioread8(0x00, &r) < 0) {
+		dev_dbg(lnw->dev, "Failed to read PMIC register 0xD2");
+		return -EBUSY;
+	}
+	if ((r & 0x03) != 0x02) {
+		dev_dbg(lnw->dev, "not NEC PMIC attached\n");
+		return -EBUSY;
+	}
+
+	if (intel_scu_ipc_ioread8(0x20, &r) < 0) {
+		dev_dbg(lnw->dev, "Failed to read PMIC register 0xD2");
+		return -EBUSY;
+	}
+
+	if ((r & 0x20) == 0) {
+		dev_dbg(lnw->dev, "no battery attached\n");
+		return -EBUSY;
+	}
+
+	/* Workaround for battery attachment issue */
+	if (r == 0x34) {
+		dev_dbg(lnw->dev, "no battery attached on SH\n");
+		return -EBUSY;
+	}
+
+	dev_dbg(lnw->dev, "battery attached. 2 reg = %x\n", r);
+
+	/* workaround: FW detect writing 0x20/0xc0 to d4 event.
+	 * this is only for NEC PMIC.
+	 */
+
+	if (intel_scu_ipc_iowrite8(0xD4, enabled ? 0x20 : 0xC0))
+		dev_dbg(lnw->dev, "Failed to write PMIC.\n");
+
+	dev_dbg(lnw->dev, "%s --->\n", __func__);
+
+	return 0;
+}
+
+/* charge vbus or discharge vbus through a resistor to ground */
+static void langwell_otg_chrg_vbus(int on)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	u32	val;
+
+	val = readl(lnw->iotg.base + CI_OTGSC);
+
+	if (on)
+		writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_VC,
+				lnw->iotg.base + CI_OTGSC);
+	else
+		writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_VD,
+				lnw->iotg.base + CI_OTGSC);
+}
+
+/* Start SRP */
+static int langwell_otg_start_srp(struct otg_transceiver *otg)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u32				val;
+
+	dev_dbg(lnw->dev, "%s --->\n", __func__);
+
+	val = readl(iotg->base + CI_OTGSC);
+
+	writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_HADP,
+				iotg->base + CI_OTGSC);
+
+	/* Check if the data plus is finished or not */
+	msleep(8);
+	val = readl(iotg->base + CI_OTGSC);
+	if (val & (OTGSC_HADP | OTGSC_DP))
+		dev_dbg(lnw->dev, "DataLine SRP Error\n");
+
+	/* Disable interrupt - b_sess_vld */
+	val = readl(iotg->base + CI_OTGSC);
+	val &= (~(OTGSC_BSVIE | OTGSC_BSEIE));
+	writel(val, iotg->base + CI_OTGSC);
+
+	/* Start VBus SRP, drive vbus to generate VBus pulse */
+	iotg->otg.set_vbus(&iotg->otg, true);
+	msleep(15);
+	iotg->otg.set_vbus(&iotg->otg, false);
+
+	/* Enable interrupt - b_sess_vld*/
+	val = readl(iotg->base + CI_OTGSC);
+	dev_dbg(lnw->dev, "after VBUS pulse otgsc = %x\n", val);
+
+	val |= (OTGSC_BSVIE | OTGSC_BSEIE);
+	writel(val, iotg->base + CI_OTGSC);
+
+	/* If Vbus is valid, then update the hsm */
+	if (val & OTGSC_BSV) {
+		dev_dbg(lnw->dev, "no b_sess_vld interrupt\n");
+
+		lnw->iotg.hsm.b_sess_vld = 1;
+		langwell_update_transceiver();
+	}
+
+	dev_dbg(lnw->dev, "%s <---\n", __func__);
+	return 0;
+}
+
+/* stop SOF via bus_suspend */
+static void langwell_otg_loc_sof(int on)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	struct usb_hcd		*hcd;
+	int			err;
+
+	dev_dbg(lnw->dev, "%s ---> %s\n", __func__, on ? "suspend" : "resume");
+
+	hcd = bus_to_hcd(lnw->iotg.otg.host);
+	if (on)
+		err = hcd->driver->bus_resume(hcd);
+	else
+		err = hcd->driver->bus_suspend(hcd);
+
+	if (err)
+		dev_dbg(lnw->dev, "Fail to resume/suspend USB bus - %d\n", err);
+
+	dev_dbg(lnw->dev, "%s <---\n", __func__);
+}
+
+static int langwell_otg_check_otgsc(void)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	u32				otgsc, usbcfg;
+
+	dev_dbg(lnw->dev, "check sync OTGSC and USBCFG registers\n");
+
+	otgsc = readl(lnw->iotg.base + CI_OTGSC);
+	usbcfg = readl(lnw->usbcfg);
+
+	dev_dbg(lnw->dev, "OTGSC = %08x, USBCFG = %08x\n",
+					otgsc, usbcfg);
+	dev_dbg(lnw->dev, "OTGSC_AVV = %d\n", !!(otgsc & OTGSC_AVV));
+	dev_dbg(lnw->dev, "USBCFG.VBUSVAL = %d\n",
+					!!(usbcfg & USBCFG_VBUSVAL));
+	dev_dbg(lnw->dev, "OTGSC_ASV = %d\n", !!(otgsc & OTGSC_ASV));
+	dev_dbg(lnw->dev, "USBCFG.AVALID = %d\n",
+					!!(usbcfg & USBCFG_AVALID));
+	dev_dbg(lnw->dev, "OTGSC_BSV = %d\n", !!(otgsc & OTGSC_BSV));
+	dev_dbg(lnw->dev, "USBCFG.BVALID = %d\n",
+					!!(usbcfg & USBCFG_BVALID));
+	dev_dbg(lnw->dev, "OTGSC_BSE = %d\n", !!(otgsc & OTGSC_BSE));
+	dev_dbg(lnw->dev, "USBCFG.SESEND = %d\n",
+					!!(usbcfg & USBCFG_SESEND));
+
+	/* Check USBCFG VBusValid/AValid/BValid/SessEnd */
+	if (!!(otgsc & OTGSC_AVV) ^ !!(usbcfg & USBCFG_VBUSVAL)) {
+		dev_dbg(lnw->dev, "OTGSC.AVV != USBCFG.VBUSVAL\n");
+		goto err;
+	}
+	if (!!(otgsc & OTGSC_ASV) ^ !!(usbcfg & USBCFG_AVALID)) {
+		dev_dbg(lnw->dev, "OTGSC.ASV != USBCFG.AVALID\n");
+		goto err;
+	}
+	if (!!(otgsc & OTGSC_BSV) ^ !!(usbcfg & USBCFG_BVALID)) {
+		dev_dbg(lnw->dev, "OTGSC.BSV != USBCFG.BVALID\n");
+		goto err;
+	}
+	if (!!(otgsc & OTGSC_BSE) ^ !!(usbcfg & USBCFG_SESEND)) {
+		dev_dbg(lnw->dev, "OTGSC.BSE != USBCFG.SESSEN\n");
+		goto err;
+	}
+
+	dev_dbg(lnw->dev, "OTGSC and USBCFG are synced\n");
+
+	return 0;
+
+err:
+	dev_warn(lnw->dev, "OTGSC isn't equal to USBCFG\n");
+	return -EPIPE;
+}
+
+
+static void langwell_otg_phy_low_power(int on)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u8				val, phcd;
+	int				retval;
+
+	dev_dbg(lnw->dev, "%s ---> %s mode\n",
+			__func__, on ? "Low power" : "Normal");
+
+	phcd = 0x40;
+
+	val = readb(iotg->base + CI_HOSTPC1 + 2);
+
+	if (on) {
+		/* Due to hardware issue, after set PHCD, sync will failed
+		 * between USBCFG and OTGSC, so before set PHCD, check if
+		 * sync is in process now. If the answer is "yes", then do
+		 * not touch PHCD bit */
+		retval = langwell_otg_check_otgsc();
+		if (retval) {
+			dev_dbg(lnw->dev, "Skip PHCD programming..\n");
+			return ;
+		}
+
+		writeb(val | phcd, iotg->base + CI_HOSTPC1 + 2);
+	} else
+		writeb(val & ~phcd, iotg->base + CI_HOSTPC1 + 2);
+
+	dev_dbg(lnw->dev, "%s <--- done\n", __func__);
+}
+
+/* After drv vbus, add 2 ms delay to set PHCD */
+static void langwell_otg_phy_low_power_wait(int on)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+
+	dev_dbg(lnw->dev, "add 2ms delay before programing PHCD\n");
+
+	mdelay(2);
+	langwell_otg_phy_low_power(on);
+}
+
+/* Enable/Disable OTG interrupt */
+static void langwell_otg_intr(int on)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u32				val;
+
+	dev_dbg(lnw->dev, "%s ---> %s\n", __func__, on ? "on" : "off");
+
+	val = readl(iotg->base + CI_OTGSC);
+
+	/* OTGSC_INT_MASK doesn't contains 1msInt */
+	if (on) {
+		val = val | (OTGSC_INT_MASK);
+		writel(val, iotg->base + CI_OTGSC);
+	} else {
+		val = val & ~(OTGSC_INT_MASK);
+		writel(val, iotg->base + CI_OTGSC);
+	}
+
+	dev_dbg(lnw->dev, "%s <---\n", __func__);
+}
+
+/* set HAAR: Hardware Assist Auto-Reset */
+static void langwell_otg_HAAR(int on)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u32				val;
+
+	dev_dbg(lnw->dev, "%s ---> %s\n", __func__, on ? "on" : "off");
+
+	val = readl(iotg->base + CI_OTGSC);
+	if (on)
+		writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_HAAR,
+					iotg->base + CI_OTGSC);
+	else
+		writel((val & ~OTGSC_INTSTS_MASK) & ~OTGSC_HAAR,
+					iotg->base + CI_OTGSC);
+
+	dev_dbg(lnw->dev, "%s <---\n", __func__);
+}
+
+/* set HABA: Hardware Assist B-Disconnect to A-Connect */
+static void langwell_otg_HABA(int on)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u32				val;
+
+	dev_dbg(lnw->dev, "%s ---> %s\n", __func__, on ? "on" : "off");
+
+	val = readl(iotg->base + CI_OTGSC);
+	if (on)
+		writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_HABA,
+					iotg->base + CI_OTGSC);
+	else
+		writel((val & ~OTGSC_INTSTS_MASK) & ~OTGSC_HABA,
+					iotg->base + CI_OTGSC);
+
+	dev_dbg(lnw->dev, "%s <---\n", __func__);
+}
+
+static int langwell_otg_check_se0_srp(int on)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	int			delay_time = TB_SE0_SRP * 10;
+	u32			val;
+
+	dev_dbg(lnw->dev, "%s --->\n", __func__);
+
+	do {
+		udelay(100);
+		if (!delay_time--)
+			break;
+		val = readl(lnw->iotg.base + CI_PORTSC1);
+		val &= PORTSC_LS;
+	} while (!val);
+
+	dev_dbg(lnw->dev, "%s <---\n", __func__);
+	return val;
+}
+
+/* The timeout callback function to set time out bit */
+static void set_tmout(unsigned long indicator)
+{
+	*(int *)indicator = 1;
+}
+
+void langwell_otg_nsf_msg(unsigned long indicator)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+
+	switch (indicator) {
+	case 2:
+	case 4:
+	case 6:
+	case 7:
+		dev_warn(lnw->dev,
+			"OTG:NSF-%lu - deivce not responding\n", indicator);
+		break;
+	case 3:
+		dev_warn(lnw->dev,
+			"OTG:NSF-%lu - deivce not supported\n", indicator);
+		break;
+	default:
+		dev_warn(lnw->dev, "Do not have this kind of NSF\n");
+		break;
+	}
+}
+
+/* Initialize timers */
+static int langwell_otg_init_timers(struct otg_hsm *hsm)
+{
+	/* HSM used timers */
+	a_wait_vrise_tmr = otg_timer_initializer(&set_tmout, TA_WAIT_VRISE,
+				(unsigned long)&hsm->a_wait_vrise_tmout);
+	if (a_wait_vrise_tmr == NULL)
+		return -ENOMEM;
+	a_aidl_bdis_tmr = otg_timer_initializer(&set_tmout, TA_AIDL_BDIS,
+				(unsigned long)&hsm->a_aidl_bdis_tmout);
+	if (a_aidl_bdis_tmr == NULL)
+		return -ENOMEM;
+	b_se0_srp_tmr = otg_timer_initializer(&set_tmout, TB_SE0_SRP,
+				(unsigned long)&hsm->b_se0_srp);
+	if (b_se0_srp_tmr == NULL)
+		return -ENOMEM;
+	b_srp_init_tmr = otg_timer_initializer(&set_tmout, TB_SRP_INIT,
+				(unsigned long)&hsm->b_srp_init_tmout);
+	if (b_srp_init_tmr == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/* Free timers */
+static void langwell_otg_free_timers(void)
+{
+	kfree(a_wait_vrise_tmr);
+	kfree(a_aidl_bdis_tmr);
+	kfree(b_se0_srp_tmr);
+	kfree(b_srp_init_tmr);
+}
+
+/* The timeout callback function to set time out bit */
+static void langwell_otg_timer_fn(unsigned long indicator)
+{
+	struct langwell_otg *lnw = the_transceiver;
+
+	*(int *)indicator = 1;
+
+	dev_dbg(lnw->dev, "kernel timer - timeout\n");
+
+	langwell_update_transceiver();
+}
+
+/* kernel timer used instead of HW based interrupt */
+static void langwell_otg_add_ktimer(enum langwell_otg_timer_type timers)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	unsigned long		j = jiffies;
+	unsigned long		data, time;
+
+	switch (timers) {
+	case TA_WAIT_VRISE_TMR:
+		iotg->hsm.a_wait_vrise_tmout = 0;
+		data = (unsigned long)&iotg->hsm.a_wait_vrise_tmout;
+		time = TA_WAIT_VRISE;
+		break;
+	case TA_WAIT_BCON_TMR:
+		iotg->hsm.a_wait_bcon_tmout = 0;
+		data = (unsigned long)&iotg->hsm.a_wait_bcon_tmout;
+		time = TA_WAIT_BCON;
+		break;
+	case TA_AIDL_BDIS_TMR:
+		iotg->hsm.a_aidl_bdis_tmout = 0;
+		data = (unsigned long)&iotg->hsm.a_aidl_bdis_tmout;
+		time = TA_AIDL_BDIS;
+		break;
+	case TB_ASE0_BRST_TMR:
+		iotg->hsm.b_ase0_brst_tmout = 0;
+		data = (unsigned long)&iotg->hsm.b_ase0_brst_tmout;
+		time = TB_ASE0_BRST;
+		break;
+	case TB_SRP_INIT_TMR:
+		iotg->hsm.b_srp_init_tmout = 0;
+		data = (unsigned long)&iotg->hsm.b_srp_init_tmout;
+		time = TB_SRP_INIT;
+		break;
+	case TB_SRP_FAIL_TMR:
+		iotg->hsm.b_srp_fail_tmout = 0;
+		data = (unsigned long)&iotg->hsm.b_srp_fail_tmout;
+		time = TB_SRP_FAIL;
+		break;
+	case TB_BUS_SUSPEND_TMR:
+		iotg->hsm.b_bus_suspend_tmout = 0;
+		data = (unsigned long)&iotg->hsm.b_bus_suspend_tmout;
+		time = TB_BUS_SUSPEND;
+		break;
+	default:
+		dev_dbg(lnw->dev, "unkown timer, cannot enable it\n");
+		return;
+	}
+
+	lnw->hsm_timer.data = data;
+	lnw->hsm_timer.function = langwell_otg_timer_fn;
+	lnw->hsm_timer.expires = j + time * HZ / 1000; /* milliseconds */
+
+	add_timer(&lnw->hsm_timer);
+
+	dev_dbg(lnw->dev, "add timer successfully\n");
+}
+
+/* Add timer to timer list */
+static void langwell_otg_add_timer(void *gtimer)
+{
+	struct langwell_otg_timer *timer = (struct langwell_otg_timer *)gtimer;
+	struct langwell_otg_timer *tmp_timer;
+	struct intel_mid_otg_xceiv *iotg = &the_transceiver->iotg;
+	u32	val32;
+
+	/* Check if the timer is already in the active list,
+	 * if so update timer count
+	 */
+	list_for_each_entry(tmp_timer, &active_timers, list)
+		if (tmp_timer == timer) {
+			timer->count = timer->expires;
+			return;
+		}
+	timer->count = timer->expires;
+
+	if (list_empty(&active_timers)) {
+		val32 = readl(iotg->base + CI_OTGSC);
+		writel(val32 | OTGSC_1MSE, iotg->base + CI_OTGSC);
+	}
+
+	list_add_tail(&timer->list, &active_timers);
+}
+
+/* Remove timer from the timer list; clear timeout status */
+static void langwell_otg_del_timer(void *gtimer)
+{
+	struct langwell_otg *lnw = the_transceiver;
+	struct langwell_otg_timer *timer = (struct langwell_otg_timer *)gtimer;
+	struct langwell_otg_timer *tmp_timer, *del_tmp;
+	u32 val32;
+
+	list_for_each_entry_safe(tmp_timer, del_tmp, &active_timers, list)
+		if (tmp_timer == timer)
+			list_del(&timer->list);
+
+	if (list_empty(&active_timers)) {
+		val32 = readl(lnw->iotg.base + CI_OTGSC);
+		writel(val32 & ~OTGSC_1MSE, lnw->iotg.base + CI_OTGSC);
+	}
+}
+
+/* Reduce timer count by 1, and find timeout conditions.*/
+static int langwell_otg_tick_timer(u32 *int_sts)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	struct langwell_otg_timer *tmp_timer, *del_tmp;
+	int expired = 0;
+
+	list_for_each_entry_safe(tmp_timer, del_tmp, &active_timers, list) {
+		tmp_timer->count--;
+		/* check if timer expires */
+		if (!tmp_timer->count) {
+			list_del(&tmp_timer->list);
+			tmp_timer->function(tmp_timer->data);
+			expired = 1;
+		}
+	}
+
+	if (list_empty(&active_timers)) {
+		dev_dbg(lnw->dev, "tick timer: disable 1ms int\n");
+		*int_sts = *int_sts & ~OTGSC_1MSE;
+	}
+	return expired;
+}
+
+static void reset_otg(void)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	int			delay_time = 1000;
+	u32			val;
+
+	dev_dbg(lnw->dev, "reseting OTG controller ...\n");
+	val = readl(lnw->iotg.base + CI_USBCMD);
+	writel(val | USBCMD_RST, lnw->iotg.base + CI_USBCMD);
+	do {
+		udelay(100);
+		if (!delay_time--)
+			dev_dbg(lnw->dev, "reset timeout\n");
+		val = readl(lnw->iotg.base + CI_USBCMD);
+		val &= USBCMD_RST;
+	} while (val != 0);
+	dev_dbg(lnw->dev, "reset done.\n");
+}
+
+static void set_host_mode(void)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	u32			val;
+
+	reset_otg();
+	val = readl(lnw->iotg.base + CI_USBMODE);
+	val = (val & (~USBMODE_CM)) | USBMODE_HOST;
+	writel(val, lnw->iotg.base + CI_USBMODE);
+}
+
+static void set_client_mode(void)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	u32			val;
+
+	reset_otg();
+	val = readl(lnw->iotg.base + CI_USBMODE);
+	val = (val & (~USBMODE_CM)) | USBMODE_DEVICE;
+	writel(val, lnw->iotg.base + CI_USBMODE);
+}
+
+static void init_hsm(void)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u32				val32;
+
+	/* read OTGSC after reset */
+	val32 = readl(lnw->iotg.base + CI_OTGSC);
+	dev_dbg(lnw->dev, "%s: OTGSC init value = 0x%x\n", __func__, val32);
+
+	/* set init state */
+	if (val32 & OTGSC_ID) {
+		iotg->hsm.id = 1;
+		iotg->otg.default_a = 0;
+		set_client_mode();
+		iotg->otg.state = OTG_STATE_B_IDLE;
+	} else {
+		iotg->hsm.id = 0;
+		iotg->otg.default_a = 1;
+		set_host_mode();
+		iotg->otg.state = OTG_STATE_A_IDLE;
+	}
+
+	/* set session indicator */
+	if (val32 & OTGSC_BSE)
+		iotg->hsm.b_sess_end = 1;
+	if (val32 & OTGSC_BSV)
+		iotg->hsm.b_sess_vld = 1;
+	if (val32 & OTGSC_ASV)
+		iotg->hsm.a_sess_vld = 1;
+	if (val32 & OTGSC_AVV)
+		iotg->hsm.a_vbus_vld = 1;
+
+	/* defautly power the bus */
+	iotg->hsm.a_bus_req = 1;
+	iotg->hsm.a_bus_drop = 0;
+	/* defautly don't request bus as B device */
+	iotg->hsm.b_bus_req = 0;
+	/* no system error */
+	iotg->hsm.a_clr_err = 0;
+
+	langwell_otg_phy_low_power_wait(1);
+}
+
+static void update_hsm(void)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u32				val32;
+
+	/* read OTGSC */
+	val32 = readl(lnw->iotg.base + CI_OTGSC);
+	dev_dbg(lnw->dev, "%s: OTGSC value = 0x%x\n", __func__, val32);
+
+	iotg->hsm.id = !!(val32 & OTGSC_ID);
+	iotg->hsm.b_sess_end = !!(val32 & OTGSC_BSE);
+	iotg->hsm.b_sess_vld = !!(val32 & OTGSC_BSV);
+	iotg->hsm.a_sess_vld = !!(val32 & OTGSC_ASV);
+	iotg->hsm.a_vbus_vld = !!(val32 & OTGSC_AVV);
+}
+
+static irqreturn_t otg_dummy_irq(int irq, void *_dev)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	void __iomem		*reg_base = _dev;
+	u32			val;
+	u32			int_mask = 0;
+
+	val = readl(reg_base + CI_USBMODE);
+	if ((val & USBMODE_CM) != USBMODE_DEVICE)
+		return IRQ_NONE;
+
+	val = readl(reg_base + CI_USBSTS);
+	int_mask = val & INTR_DUMMY_MASK;
+
+	if (int_mask == 0)
+		return IRQ_NONE;
+
+	/* clear hsm.b_conn here since host driver can't detect it
+	*  otg_dummy_irq called means B-disconnect happened.
+	*/
+	if (lnw->iotg.hsm.b_conn) {
+		lnw->iotg.hsm.b_conn = 0;
+		if (spin_trylock(&lnw->wq_lock)) {
+			langwell_update_transceiver();
+			spin_unlock(&lnw->wq_lock);
+		}
+	}
+
+	/* Clear interrupts */
+	writel(int_mask, reg_base + CI_USBSTS);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t otg_irq(int irq, void *_dev)
+{
+	struct langwell_otg		*lnw = _dev;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	u32				int_sts, int_en;
+	u32				int_mask = 0;
+	int				flag = 0;
+
+	int_sts = readl(lnw->iotg.base + CI_OTGSC);
+	int_en = (int_sts & OTGSC_INTEN_MASK) >> 8;
+	int_mask = int_sts & int_en;
+	if (int_mask == 0)
+		return IRQ_NONE;
+
+	if (int_mask & OTGSC_IDIS) {
+		dev_dbg(lnw->dev, "%s: id change int\n", __func__);
+		iotg->hsm.id = (int_sts & OTGSC_ID) ? 1 : 0;
+		dev_dbg(lnw->dev, "id = %d\n", iotg->hsm.id);
+		flag = 1;
+	}
+	if (int_mask & OTGSC_DPIS) {
+		dev_dbg(lnw->dev, "%s: data pulse int\n", __func__);
+		iotg->hsm.a_srp_det = (int_sts & OTGSC_DPS) ? 1 : 0;
+		dev_dbg(lnw->dev, "data pulse = %d\n", iotg->hsm.a_srp_det);
+		flag = 1;
+	}
+	if (int_mask & OTGSC_BSEIS) {
+		dev_dbg(lnw->dev, "%s: b session end int\n", __func__);
+		iotg->hsm.b_sess_end = (int_sts & OTGSC_BSE) ? 1 : 0;
+		dev_dbg(lnw->dev, "b_sess_end = %d\n", iotg->hsm.b_sess_end);
+		flag = 1;
+	}
+	if (int_mask & OTGSC_BSVIS) {
+		dev_dbg(lnw->dev, "%s: b session valid int\n", __func__);
+		iotg->hsm.b_sess_vld = (int_sts & OTGSC_BSV) ? 1 : 0;
+		dev_dbg(lnw->dev, "b_sess_vld = %d\n", iotg->hsm.b_sess_end);
+		flag = 1;
+	}
+	if (int_mask & OTGSC_ASVIS) {
+		dev_dbg(lnw->dev, "%s: a session valid int\n", __func__);
+		iotg->hsm.a_sess_vld = (int_sts & OTGSC_ASV) ? 1 : 0;
+		dev_dbg(lnw->dev, "a_sess_vld = %d\n", iotg->hsm.a_sess_vld);
+		flag = 1;
+	}
+	if (int_mask & OTGSC_AVVIS) {
+		dev_dbg(lnw->dev, "%s: a vbus valid int\n", __func__);
+		iotg->hsm.a_vbus_vld = (int_sts & OTGSC_AVV) ? 1 : 0;
+		dev_dbg(lnw->dev, "a_vbus_vld = %d\n", iotg->hsm.a_vbus_vld);
+		flag = 1;
+	}
+
+	if (int_mask & OTGSC_1MSS) {
+		/* need to schedule otg_work if any timer is expired */
+		if (langwell_otg_tick_timer(&int_sts))
+			flag = 1;
+	}
+
+	writel((int_sts & ~OTGSC_INTSTS_MASK) | int_mask,
+					lnw->iotg.base + CI_OTGSC);
+	if (flag)
+		langwell_update_transceiver();
+
+	return IRQ_HANDLED;
+}
+
+static int langwell_otg_iotg_notify(struct notifier_block *nb,
+				unsigned long action, void *data)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = data;
+	int				flag = 0;
+
+	if (iotg == NULL)
+		return NOTIFY_BAD;
+
+	if (lnw == NULL)
+		return NOTIFY_BAD;
+
+	switch (action) {
+	case MID_OTG_NOTIFY_CONNECT:
+		dev_dbg(lnw->dev, "Lnw OTG Notify Connect Event\n");
+		if (iotg->otg.default_a == 1)
+			iotg->hsm.b_conn = 1;
+		else
+			iotg->hsm.a_conn = 1;
+		flag = 1;
+		break;
+	case MID_OTG_NOTIFY_DISCONN:
+		dev_dbg(lnw->dev, "Lnw OTG Notify Disconnect Event\n");
+		if (iotg->otg.default_a == 1)
+			iotg->hsm.b_conn = 0;
+		else
+			iotg->hsm.a_conn = 0;
+		flag = 1;
+		break;
+	case MID_OTG_NOTIFY_HSUSPEND:
+		dev_dbg(lnw->dev, "Lnw OTG Notify Host Bus suspend Event\n");
+		if (iotg->otg.default_a == 1)
+			iotg->hsm.a_suspend_req = 1;
+		else
+			iotg->hsm.b_bus_req = 0;
+		flag = 1;
+		break;
+	case MID_OTG_NOTIFY_HRESUME:
+		dev_dbg(lnw->dev, "Lnw OTG Notify Host Bus resume Event\n");
+		if (iotg->otg.default_a == 1)
+			iotg->hsm.b_bus_resume = 1;
+		flag = 1;
+		break;
+	case MID_OTG_NOTIFY_CSUSPEND:
+		dev_dbg(lnw->dev, "Lnw OTG Notify Client Bus suspend Event\n");
+		if (iotg->otg.default_a == 1) {
+			if (iotg->hsm.b_bus_suspend_vld == 2) {
+				iotg->hsm.b_bus_suspend = 1;
+				iotg->hsm.b_bus_suspend_vld = 0;
+				flag = 1;
+			} else {
+				iotg->hsm.b_bus_suspend_vld++;
+				flag = 0;
+			}
+		} else {
+			if (iotg->hsm.a_bus_suspend == 0) {
+				iotg->hsm.a_bus_suspend = 1;
+				flag = 1;
+			}
+		}
+		break;
+	case MID_OTG_NOTIFY_CRESUME:
+		dev_dbg(lnw->dev, "Lnw OTG Notify Client Bus resume Event\n");
+		if (iotg->otg.default_a == 0)
+			iotg->hsm.a_bus_suspend = 0;
+		flag = 0;
+		break;
+	case MID_OTG_NOTIFY_HOSTADD:
+		dev_dbg(lnw->dev, "Lnw OTG Nofity Host Driver Add\n");
+		flag = 1;
+		break;
+	case MID_OTG_NOTIFY_HOSTREMOVE:
+		dev_dbg(lnw->dev, "Lnw OTG Nofity Host Driver remove\n");
+		flag = 1;
+		break;
+	case MID_OTG_NOTIFY_CLIENTADD:
+		dev_dbg(lnw->dev, "Lnw OTG Nofity Client Driver Add\n");
+		flag = 1;
+		break;
+	case MID_OTG_NOTIFY_CLIENTREMOVE:
+		dev_dbg(lnw->dev, "Lnw OTG Nofity Client Driver remove\n");
+		flag = 1;
+		break;
+	default:
+		dev_dbg(lnw->dev, "Lnw OTG Nofity unknown notify message\n");
+		return NOTIFY_DONE;
+	}
+
+	if (flag)
+		langwell_update_transceiver();
+
+	return NOTIFY_OK;
+}
+
+static void langwell_otg_work(struct work_struct *work)
+{
+	struct langwell_otg		*lnw;
+	struct intel_mid_otg_xceiv	*iotg;
+	int				retval;
+	struct pci_dev			*pdev;
+
+	lnw = container_of(work, struct langwell_otg, work);
+	iotg = &lnw->iotg;
+	pdev = to_pci_dev(lnw->dev);
+
+	dev_dbg(lnw->dev, "%s: old state = %s\n", __func__,
+			state_string(iotg->otg.state));
+
+	switch (iotg->otg.state) {
+	case OTG_STATE_UNDEFINED:
+	case OTG_STATE_B_IDLE:
+		if (!iotg->hsm.id) {
+			langwell_otg_del_timer(b_srp_init_tmr);
+			del_timer_sync(&lnw->hsm_timer);
+
+			iotg->otg.default_a = 1;
+			iotg->hsm.a_srp_det = 0;
+
+			langwell_otg_chrg_vbus(0);
+			set_host_mode();
+			langwell_otg_phy_low_power(1);
+
+			iotg->otg.state = OTG_STATE_A_IDLE;
+			langwell_update_transceiver();
+		} else if (iotg->hsm.b_sess_vld) {
+			langwell_otg_del_timer(b_srp_init_tmr);
+			del_timer_sync(&lnw->hsm_timer);
+			iotg->hsm.b_sess_end = 0;
+			iotg->hsm.a_bus_suspend = 0;
+			langwell_otg_chrg_vbus(0);
+
+			if (lnw->iotg.start_peripheral) {
+				lnw->iotg.start_peripheral(&lnw->iotg);
+				iotg->otg.state = OTG_STATE_B_PERIPHERAL;
+			} else
+				dev_dbg(lnw->dev, "client driver not loaded\n");
+
+		} else if (iotg->hsm.b_srp_init_tmout) {
+			iotg->hsm.b_srp_init_tmout = 0;
+			dev_warn(lnw->dev, "SRP init timeout\n");
+		} else if (iotg->hsm.b_srp_fail_tmout) {
+			iotg->hsm.b_srp_fail_tmout = 0;
+			iotg->hsm.b_bus_req = 0;
+
+			/* No silence failure */
+			langwell_otg_nsf_msg(6);
+		} else if (iotg->hsm.b_bus_req && iotg->hsm.b_sess_end) {
+			del_timer_sync(&lnw->hsm_timer);
+			/* workaround for b_se0_srp detection */
+			retval = langwell_otg_check_se0_srp(0);
+			if (retval) {
+				iotg->hsm.b_bus_req = 0;
+				dev_dbg(lnw->dev, "LS isn't SE0, try later\n");
+			} else {
+				/* clear the PHCD before start srp */
+				langwell_otg_phy_low_power(0);
+
+				/* Start SRP */
+				langwell_otg_add_timer(b_srp_init_tmr);
+				iotg->otg.start_srp(&iotg->otg);
+				langwell_otg_del_timer(b_srp_init_tmr);
+				langwell_otg_add_ktimer(TB_SRP_FAIL_TMR);
+
+				/* reset PHY low power mode here */
+				langwell_otg_phy_low_power_wait(1);
+			}
+		}
+		break;
+	case OTG_STATE_B_SRP_INIT:
+		if (!iotg->hsm.id) {
+			iotg->otg.default_a = 1;
+			iotg->hsm.a_srp_det = 0;
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			langwell_otg_chrg_vbus(0);
+			set_host_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_A_IDLE;
+			langwell_update_transceiver();
+		} else if (iotg->hsm.b_sess_vld) {
+			langwell_otg_chrg_vbus(0);
+			if (lnw->iotg.start_peripheral) {
+				lnw->iotg.start_peripheral(&lnw->iotg);
+				iotg->otg.state = OTG_STATE_B_PERIPHERAL;
+			} else
+				dev_dbg(lnw->dev, "client driver not loaded\n");
+		}
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		if (!iotg->hsm.id) {
+			iotg->otg.default_a = 1;
+			iotg->hsm.a_srp_det = 0;
+
+			langwell_otg_chrg_vbus(0);
+
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			set_host_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_A_IDLE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.b_sess_vld) {
+			iotg->hsm.b_hnp_enable = 0;
+
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			iotg->otg.state = OTG_STATE_B_IDLE;
+		} else if (iotg->hsm.b_bus_req && iotg->otg.gadget &&
+					iotg->otg.gadget->b_hnp_enable &&
+					iotg->hsm.a_bus_suspend) {
+
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			langwell_otg_HAAR(1);
+			iotg->hsm.a_conn = 0;
+
+			if (lnw->iotg.start_host) {
+				lnw->iotg.start_host(&lnw->iotg);
+				iotg->otg.state = OTG_STATE_B_WAIT_ACON;
+			} else
+				dev_dbg(lnw->dev,
+						"host driver not loaded.\n");
+
+			iotg->hsm.a_bus_resume = 0;
+			langwell_otg_add_ktimer(TB_ASE0_BRST_TMR);
+		}
+		break;
+
+	case OTG_STATE_B_WAIT_ACON:
+		if (!iotg->hsm.id) {
+			/* delete hsm timer for b_ase0_brst_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			iotg->otg.default_a = 1;
+			iotg->hsm.a_srp_det = 0;
+
+			langwell_otg_chrg_vbus(0);
+
+			langwell_otg_HAAR(0);
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			set_host_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_A_IDLE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.b_sess_vld) {
+			/* delete hsm timer for b_ase0_brst_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			iotg->hsm.b_hnp_enable = 0;
+			iotg->hsm.b_bus_req = 0;
+
+			langwell_otg_chrg_vbus(0);
+			langwell_otg_HAAR(0);
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			set_client_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+		} else if (iotg->hsm.a_conn) {
+			/* delete hsm timer for b_ase0_brst_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			langwell_otg_HAAR(0);
+			iotg->otg.state = OTG_STATE_B_HOST;
+			langwell_update_transceiver();
+		} else if (iotg->hsm.a_bus_resume ||
+				iotg->hsm.b_ase0_brst_tmout) {
+			/* delete hsm timer for b_ase0_brst_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			langwell_otg_HAAR(0);
+			langwell_otg_nsf_msg(7);
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			iotg->hsm.a_bus_suspend = 0;
+			iotg->hsm.b_bus_req = 0;
+
+			if (lnw->iotg.start_peripheral)
+				lnw->iotg.start_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver not loaded.\n");
+
+			iotg->otg.state = OTG_STATE_B_PERIPHERAL;
+		}
+		break;
+
+	case OTG_STATE_B_HOST:
+		if (!iotg->hsm.id) {
+			iotg->otg.default_a = 1;
+			iotg->hsm.a_srp_det = 0;
+
+			langwell_otg_chrg_vbus(0);
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			set_host_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_A_IDLE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.b_sess_vld) {
+			iotg->hsm.b_hnp_enable = 0;
+			iotg->hsm.b_bus_req = 0;
+
+			langwell_otg_chrg_vbus(0);
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			set_client_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+		} else if ((!iotg->hsm.b_bus_req) ||
+				(!iotg->hsm.a_conn)) {
+			iotg->hsm.b_bus_req = 0;
+			langwell_otg_loc_sof(0);
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			iotg->hsm.a_bus_suspend = 0;
+
+			if (lnw->iotg.start_peripheral)
+				lnw->iotg.start_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+						"client driver not loaded.\n");
+
+			iotg->otg.state = OTG_STATE_B_PERIPHERAL;
+		}
+		break;
+
+	case OTG_STATE_A_IDLE:
+		iotg->otg.default_a = 1;
+		if (iotg->hsm.id) {
+			iotg->otg.default_a = 0;
+			iotg->hsm.b_bus_req = 0;
+			iotg->hsm.vbus_srp_up = 0;
+
+			langwell_otg_chrg_vbus(0);
+			set_client_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.a_bus_drop &&
+			(iotg->hsm.a_srp_det || iotg->hsm.a_bus_req)) {
+			langwell_otg_phy_low_power(0);
+
+			/* Turn on VBus */
+			iotg->otg.set_vbus(&iotg->otg, true);
+
+			iotg->hsm.vbus_srp_up = 0;
+			iotg->hsm.a_wait_vrise_tmout = 0;
+			langwell_otg_add_timer(a_wait_vrise_tmr);
+			iotg->otg.state = OTG_STATE_A_WAIT_VRISE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.a_bus_drop && iotg->hsm.a_sess_vld) {
+			iotg->hsm.vbus_srp_up = 1;
+		} else if (!iotg->hsm.a_sess_vld && iotg->hsm.vbus_srp_up) {
+			msleep(10);
+			langwell_otg_phy_low_power(0);
+
+			/* Turn on VBus */
+			iotg->otg.set_vbus(&iotg->otg, true);
+			iotg->hsm.a_srp_det = 1;
+			iotg->hsm.vbus_srp_up = 0;
+			iotg->hsm.a_wait_vrise_tmout = 0;
+			langwell_otg_add_timer(a_wait_vrise_tmr);
+			iotg->otg.state = OTG_STATE_A_WAIT_VRISE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.a_sess_vld &&
+				!iotg->hsm.vbus_srp_up) {
+			langwell_otg_phy_low_power(1);
+		}
+		break;
+	case OTG_STATE_A_WAIT_VRISE:
+		if (iotg->hsm.id) {
+			langwell_otg_del_timer(a_wait_vrise_tmr);
+			iotg->hsm.b_bus_req = 0;
+			iotg->otg.default_a = 0;
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			set_client_mode();
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+		} else if (iotg->hsm.a_vbus_vld) {
+			langwell_otg_del_timer(a_wait_vrise_tmr);
+			iotg->hsm.b_conn = 0;
+			if (lnw->iotg.start_host)
+				lnw->iotg.start_host(&lnw->iotg);
+			else {
+				dev_dbg(lnw->dev, "host driver not loaded.\n");
+				break;
+			}
+
+			langwell_otg_add_ktimer(TA_WAIT_BCON_TMR);
+			iotg->otg.state = OTG_STATE_A_WAIT_BCON;
+		} else if (iotg->hsm.a_wait_vrise_tmout) {
+			iotg->hsm.b_conn = 0;
+			if (iotg->hsm.a_vbus_vld) {
+				if (lnw->iotg.start_host)
+					lnw->iotg.start_host(&lnw->iotg);
+				else {
+					dev_dbg(lnw->dev,
+						"host driver not loaded.\n");
+					break;
+				}
+				langwell_otg_add_ktimer(TA_WAIT_BCON_TMR);
+				iotg->otg.state = OTG_STATE_A_WAIT_BCON;
+			} else {
+
+				/* Turn off VBus */
+				iotg->otg.set_vbus(&iotg->otg, false);
+				langwell_otg_phy_low_power_wait(1);
+				iotg->otg.state = OTG_STATE_A_VBUS_ERR;
+			}
+		}
+		break;
+	case OTG_STATE_A_WAIT_BCON:
+		if (iotg->hsm.id) {
+			/* delete hsm timer for a_wait_bcon_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			iotg->otg.default_a = 0;
+			iotg->hsm.b_bus_req = 0;
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			set_client_mode();
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.a_vbus_vld) {
+			/* delete hsm timer for a_wait_bcon_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_A_VBUS_ERR;
+		} else if (iotg->hsm.a_bus_drop ||
+				(iotg->hsm.a_wait_bcon_tmout &&
+				!iotg->hsm.a_bus_req)) {
+			/* delete hsm timer for a_wait_bcon_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			iotg->otg.state = OTG_STATE_A_WAIT_VFALL;
+		} else if (iotg->hsm.b_conn) {
+			/* delete hsm timer for a_wait_bcon_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			iotg->hsm.a_suspend_req = 0;
+			iotg->otg.state = OTG_STATE_A_HOST;
+			if (iotg->hsm.a_srp_det && iotg->otg.host &&
+					!iotg->otg.host->b_hnp_enable) {
+				/* SRP capable peripheral-only device */
+				iotg->hsm.a_bus_req = 1;
+				iotg->hsm.a_srp_det = 0;
+			} else if (!iotg->hsm.a_bus_req && iotg->otg.host &&
+					iotg->otg.host->b_hnp_enable) {
+				/* It is not safe enough to do a fast
+				 * transistion from A_WAIT_BCON to
+				 * A_SUSPEND */
+				msleep(10000);
+				if (iotg->hsm.a_bus_req)
+					break;
+
+				if (request_irq(pdev->irq,
+					otg_dummy_irq, IRQF_SHARED,
+					driver_name, iotg->base) != 0) {
+					dev_dbg(lnw->dev,
+						"request interrupt %d fail\n",
+						pdev->irq);
+				}
+
+				langwell_otg_HABA(1);
+				iotg->hsm.b_bus_resume = 0;
+				iotg->hsm.a_aidl_bdis_tmout = 0;
+
+				langwell_otg_loc_sof(0);
+				/* clear PHCD to enable HW timer */
+				langwell_otg_phy_low_power(0);
+				langwell_otg_add_timer(a_aidl_bdis_tmr);
+				iotg->otg.state = OTG_STATE_A_SUSPEND;
+			} else if (!iotg->hsm.a_bus_req && iotg->otg.host &&
+				!iotg->otg.host->b_hnp_enable) {
+				if (lnw->iotg.stop_host)
+					lnw->iotg.stop_host(&lnw->iotg);
+				else
+					dev_dbg(lnw->dev,
+						"host driver removed.\n");
+
+				/* Turn off VBus */
+				iotg->otg.set_vbus(&iotg->otg, false);
+				iotg->otg.state = OTG_STATE_A_WAIT_VFALL;
+			}
+		}
+		break;
+	case OTG_STATE_A_HOST:
+		if (iotg->hsm.id) {
+			iotg->otg.default_a = 0;
+			iotg->hsm.b_bus_req = 0;
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			set_client_mode();
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+			langwell_update_transceiver();
+		} else if (iotg->hsm.a_bus_drop ||
+				(iotg->otg.host &&
+				!iotg->otg.host->b_hnp_enable &&
+					!iotg->hsm.a_bus_req)) {
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			iotg->otg.state = OTG_STATE_A_WAIT_VFALL;
+		} else if (!iotg->hsm.a_vbus_vld) {
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_A_VBUS_ERR;
+		} else if (iotg->otg.host &&
+				iotg->otg.host->b_hnp_enable &&
+				!iotg->hsm.a_bus_req) {
+			/* Set HABA to enable hardware assistance to signal
+			 *  A-connect after receiver B-disconnect. Hardware
+			 *  will then set client mode and enable URE, SLE and
+			 *  PCE after the assistance. otg_dummy_irq is used to
+			 *  clean these ints when client driver is not resumed.
+			 */
+			if (request_irq(pdev->irq, otg_dummy_irq, IRQF_SHARED,
+					driver_name, iotg->base) != 0) {
+				dev_dbg(lnw->dev,
+					"request interrupt %d failed\n",
+						pdev->irq);
+			}
+
+			/* set HABA */
+			langwell_otg_HABA(1);
+			iotg->hsm.b_bus_resume = 0;
+			iotg->hsm.a_aidl_bdis_tmout = 0;
+			langwell_otg_loc_sof(0);
+			/* clear PHCD to enable HW timer */
+			langwell_otg_phy_low_power(0);
+			langwell_otg_add_timer(a_aidl_bdis_tmr);
+			iotg->otg.state = OTG_STATE_A_SUSPEND;
+		} else if (!iotg->hsm.b_conn || !iotg->hsm.a_bus_req) {
+			langwell_otg_add_ktimer(TA_WAIT_BCON_TMR);
+			iotg->otg.state = OTG_STATE_A_WAIT_BCON;
+		}
+		break;
+	case OTG_STATE_A_SUSPEND:
+		if (iotg->hsm.id) {
+			langwell_otg_del_timer(a_aidl_bdis_tmr);
+			langwell_otg_HABA(0);
+			free_irq(pdev->irq, iotg->base);
+			iotg->otg.default_a = 0;
+			iotg->hsm.b_bus_req = 0;
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			set_client_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+			langwell_update_transceiver();
+		} else if (iotg->hsm.a_bus_req ||
+				iotg->hsm.b_bus_resume) {
+			langwell_otg_del_timer(a_aidl_bdis_tmr);
+			langwell_otg_HABA(0);
+			free_irq(pdev->irq, iotg->base);
+			iotg->hsm.a_suspend_req = 0;
+			langwell_otg_loc_sof(1);
+			iotg->otg.state = OTG_STATE_A_HOST;
+		} else if (iotg->hsm.a_aidl_bdis_tmout ||
+				iotg->hsm.a_bus_drop) {
+			langwell_otg_del_timer(a_aidl_bdis_tmr);
+			langwell_otg_HABA(0);
+			free_irq(pdev->irq, iotg->base);
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			iotg->otg.state = OTG_STATE_A_WAIT_VFALL;
+		} else if (!iotg->hsm.b_conn && iotg->otg.host &&
+				iotg->otg.host->b_hnp_enable) {
+			langwell_otg_del_timer(a_aidl_bdis_tmr);
+			langwell_otg_HABA(0);
+			free_irq(pdev->irq, iotg->base);
+
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			iotg->hsm.b_bus_suspend = 0;
+			iotg->hsm.b_bus_suspend_vld = 0;
+
+			/* msleep(200); */
+			if (lnw->iotg.start_peripheral)
+				lnw->iotg.start_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver not loaded.\n");
+
+			langwell_otg_add_ktimer(TB_BUS_SUSPEND_TMR);
+			iotg->otg.state = OTG_STATE_A_PERIPHERAL;
+			break;
+		} else if (!iotg->hsm.a_vbus_vld) {
+			langwell_otg_del_timer(a_aidl_bdis_tmr);
+			langwell_otg_HABA(0);
+			free_irq(pdev->irq, iotg->base);
+			if (lnw->iotg.stop_host)
+				lnw->iotg.stop_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"host driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_A_VBUS_ERR;
+		}
+		break;
+	case OTG_STATE_A_PERIPHERAL:
+		if (iotg->hsm.id) {
+			/* delete hsm timer for b_bus_suspend_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+			iotg->otg.default_a = 0;
+			iotg->hsm.b_bus_req = 0;
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			set_client_mode();
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+			langwell_update_transceiver();
+		} else if (!iotg->hsm.a_vbus_vld) {
+			/* delete hsm timer for b_bus_suspend_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			langwell_otg_phy_low_power_wait(1);
+			iotg->otg.state = OTG_STATE_A_VBUS_ERR;
+		} else if (iotg->hsm.a_bus_drop) {
+			/* delete hsm timer for b_bus_suspend_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			/* Turn off VBus */
+			iotg->otg.set_vbus(&iotg->otg, false);
+			iotg->otg.state = OTG_STATE_A_WAIT_VFALL;
+		} else if (iotg->hsm.b_bus_suspend) {
+			/* delete hsm timer for b_bus_suspend_tmr */
+			del_timer_sync(&lnw->hsm_timer);
+
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			if (lnw->iotg.start_host)
+				lnw->iotg.start_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+						"host driver not loaded.\n");
+			langwell_otg_add_ktimer(TA_WAIT_BCON_TMR);
+			iotg->otg.state = OTG_STATE_A_WAIT_BCON;
+		} else if (iotg->hsm.b_bus_suspend_tmout) {
+			u32	val;
+			val = readl(lnw->iotg.base + CI_PORTSC1);
+			if (!(val & PORTSC_SUSP))
+				break;
+
+			if (lnw->iotg.stop_peripheral)
+				lnw->iotg.stop_peripheral(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+					"client driver has been removed.\n");
+
+			if (lnw->iotg.start_host)
+				lnw->iotg.start_host(&lnw->iotg);
+			else
+				dev_dbg(lnw->dev,
+						"host driver not loaded.\n");
+			langwell_otg_add_ktimer(TA_WAIT_BCON_TMR);
+			iotg->otg.state = OTG_STATE_A_WAIT_BCON;
+		}
+		break;
+	case OTG_STATE_A_VBUS_ERR:
+		if (iotg->hsm.id) {
+			iotg->otg.default_a = 0;
+			iotg->hsm.a_clr_err = 0;
+			iotg->hsm.a_srp_det = 0;
+			set_client_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+			langwell_update_transceiver();
+		} else if (iotg->hsm.a_clr_err) {
+			iotg->hsm.a_clr_err = 0;
+			iotg->hsm.a_srp_det = 0;
+			reset_otg();
+			init_hsm();
+			if (iotg->otg.state == OTG_STATE_A_IDLE)
+				langwell_update_transceiver();
+		} else {
+			/* FW will clear PHCD bit when any VBus
+			 * event detected. Reset PHCD to 1 again */
+			langwell_otg_phy_low_power(1);
+		}
+		break;
+	case OTG_STATE_A_WAIT_VFALL:
+		if (iotg->hsm.id) {
+			iotg->otg.default_a = 0;
+			set_client_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_B_IDLE;
+			langwell_update_transceiver();
+		} else if (iotg->hsm.a_bus_req) {
+
+			/* Turn on VBus */
+			iotg->otg.set_vbus(&iotg->otg, true);
+			iotg->hsm.a_wait_vrise_tmout = 0;
+			langwell_otg_add_timer(a_wait_vrise_tmr);
+			iotg->otg.state = OTG_STATE_A_WAIT_VRISE;
+		} else if (!iotg->hsm.a_sess_vld) {
+			iotg->hsm.a_srp_det = 0;
+			set_host_mode();
+			langwell_otg_phy_low_power(1);
+			iotg->otg.state = OTG_STATE_A_IDLE;
+		}
+		break;
+	default:
+		;
+	}
+
+	dev_dbg(lnw->dev, "%s: new state = %s\n", __func__,
+			state_string(iotg->otg.state));
+}
+
+static ssize_t
+show_registers(struct device *_dev, struct device_attribute *attr, char *buf)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	char			*next;
+	unsigned		size, t;
+
+	next = buf;
+	size = PAGE_SIZE;
+
+	t = scnprintf(next, size,
+		"\n"
+		"USBCMD = 0x%08x\n"
+		"USBSTS = 0x%08x\n"
+		"USBINTR = 0x%08x\n"
+		"ASYNCLISTADDR = 0x%08x\n"
+		"PORTSC1 = 0x%08x\n"
+		"HOSTPC1 = 0x%08x\n"
+		"OTGSC = 0x%08x\n"
+		"USBMODE = 0x%08x\n",
+		readl(lnw->iotg.base + 0x30),
+		readl(lnw->iotg.base + 0x34),
+		readl(lnw->iotg.base + 0x38),
+		readl(lnw->iotg.base + 0x48),
+		readl(lnw->iotg.base + 0x74),
+		readl(lnw->iotg.base + 0xb4),
+		readl(lnw->iotg.base + 0xf4),
+		readl(lnw->iotg.base + 0xf8)
+	     );
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+static DEVICE_ATTR(registers, S_IRUGO, show_registers, NULL);
+
+static ssize_t
+show_hsm(struct device *_dev, struct device_attribute *attr, char *buf)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	char				*next;
+	unsigned			size, t;
+
+	next = buf;
+	size = PAGE_SIZE;
+
+	if (iotg->otg.host)
+		iotg->hsm.a_set_b_hnp_en = iotg->otg.host->b_hnp_enable;
+
+	if (iotg->otg.gadget)
+		iotg->hsm.b_hnp_enable = iotg->otg.gadget->b_hnp_enable;
+
+	t = scnprintf(next, size,
+		"\n"
+		"current state = %s\n"
+		"a_bus_resume = \t%d\n"
+		"a_bus_suspend = \t%d\n"
+		"a_conn = \t%d\n"
+		"a_sess_vld = \t%d\n"
+		"a_srp_det = \t%d\n"
+		"a_vbus_vld = \t%d\n"
+		"b_bus_resume = \t%d\n"
+		"b_bus_suspend = \t%d\n"
+		"b_conn = \t%d\n"
+		"b_se0_srp = \t%d\n"
+		"b_sess_end = \t%d\n"
+		"b_sess_vld = \t%d\n"
+		"id = \t%d\n"
+		"a_set_b_hnp_en = \t%d\n"
+		"b_srp_done = \t%d\n"
+		"b_hnp_enable = \t%d\n"
+		"a_wait_vrise_tmout = \t%d\n"
+		"a_wait_bcon_tmout = \t%d\n"
+		"a_aidl_bdis_tmout = \t%d\n"
+		"b_ase0_brst_tmout = \t%d\n"
+		"a_bus_drop = \t%d\n"
+		"a_bus_req = \t%d\n"
+		"a_clr_err = \t%d\n"
+		"a_suspend_req = \t%d\n"
+		"b_bus_req = \t%d\n"
+		"b_bus_suspend_tmout = \t%d\n"
+		"b_bus_suspend_vld = \t%d\n",
+		state_string(iotg->otg.state),
+		iotg->hsm.a_bus_resume,
+		iotg->hsm.a_bus_suspend,
+		iotg->hsm.a_conn,
+		iotg->hsm.a_sess_vld,
+		iotg->hsm.a_srp_det,
+		iotg->hsm.a_vbus_vld,
+		iotg->hsm.b_bus_resume,
+		iotg->hsm.b_bus_suspend,
+		iotg->hsm.b_conn,
+		iotg->hsm.b_se0_srp,
+		iotg->hsm.b_sess_end,
+		iotg->hsm.b_sess_vld,
+		iotg->hsm.id,
+		iotg->hsm.a_set_b_hnp_en,
+		iotg->hsm.b_srp_done,
+		iotg->hsm.b_hnp_enable,
+		iotg->hsm.a_wait_vrise_tmout,
+		iotg->hsm.a_wait_bcon_tmout,
+		iotg->hsm.a_aidl_bdis_tmout,
+		iotg->hsm.b_ase0_brst_tmout,
+		iotg->hsm.a_bus_drop,
+		iotg->hsm.a_bus_req,
+		iotg->hsm.a_clr_err,
+		iotg->hsm.a_suspend_req,
+		iotg->hsm.b_bus_req,
+		iotg->hsm.b_bus_suspend_tmout,
+		iotg->hsm.b_bus_suspend_vld
+		);
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+static DEVICE_ATTR(hsm, S_IRUGO, show_hsm, NULL);
+
+static ssize_t
+get_a_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	char			*next;
+	unsigned		size, t;
+
+	next = buf;
+	size = PAGE_SIZE;
+
+	t = scnprintf(next, size, "%d", lnw->iotg.hsm.a_bus_req);
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+
+static ssize_t
+set_a_bus_req(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+
+	if (!iotg->otg.default_a)
+		return -1;
+	if (count > 2)
+		return -1;
+
+	if (buf[0] == '0') {
+		iotg->hsm.a_bus_req = 0;
+		dev_dbg(lnw->dev, "User request: a_bus_req = 0\n");
+	} else if (buf[0] == '1') {
+		/* If a_bus_drop is TRUE, a_bus_req can't be set */
+		if (iotg->hsm.a_bus_drop)
+			return -1;
+		iotg->hsm.a_bus_req = 1;
+		dev_dbg(lnw->dev, "User request: a_bus_req = 1\n");
+	}
+	if (spin_trylock(&lnw->wq_lock)) {
+		langwell_update_transceiver();
+		spin_unlock(&lnw->wq_lock);
+	}
+	return count;
+}
+static DEVICE_ATTR(a_bus_req, S_IRUGO | S_IWUGO, get_a_bus_req, set_a_bus_req);
+
+static ssize_t
+get_a_bus_drop(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	char			*next;
+	unsigned		size, t;
+
+	next = buf;
+	size = PAGE_SIZE;
+
+	t = scnprintf(next, size, "%d", lnw->iotg.hsm.a_bus_drop);
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+
+static ssize_t
+set_a_bus_drop(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+
+	if (!iotg->otg.default_a)
+		return -1;
+	if (count > 2)
+		return -1;
+
+	if (buf[0] == '0') {
+		iotg->hsm.a_bus_drop = 0;
+		dev_dbg(lnw->dev, "User request: a_bus_drop = 0\n");
+	} else if (buf[0] == '1') {
+		iotg->hsm.a_bus_drop = 1;
+		iotg->hsm.a_bus_req = 0;
+		dev_dbg(lnw->dev, "User request: a_bus_drop = 1\n");
+		dev_dbg(lnw->dev, "User request: and a_bus_req = 0\n");
+	}
+	if (spin_trylock(&lnw->wq_lock)) {
+		langwell_update_transceiver();
+		spin_unlock(&lnw->wq_lock);
+	}
+	return count;
+}
+static DEVICE_ATTR(a_bus_drop, S_IRUGO | S_IWUGO,
+	get_a_bus_drop, set_a_bus_drop);
+
+static ssize_t
+get_b_bus_req(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	char			*next;
+	unsigned		size, t;
+
+	next = buf;
+	size = PAGE_SIZE;
+
+	t = scnprintf(next, size, "%d", lnw->iotg.hsm.b_bus_req);
+	size -= t;
+	next += t;
+
+	return PAGE_SIZE - size;
+}
+
+static ssize_t
+set_b_bus_req(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+
+	if (iotg->otg.default_a)
+		return -1;
+
+	if (count > 2)
+		return -1;
+
+	if (buf[0] == '0') {
+		iotg->hsm.b_bus_req = 0;
+		dev_dbg(lnw->dev, "User request: b_bus_req = 0\n");
+	} else if (buf[0] == '1') {
+		iotg->hsm.b_bus_req = 1;
+		dev_dbg(lnw->dev, "User request: b_bus_req = 1\n");
+	}
+	if (spin_trylock(&lnw->wq_lock)) {
+		langwell_update_transceiver();
+		spin_unlock(&lnw->wq_lock);
+	}
+	return count;
+}
+static DEVICE_ATTR(b_bus_req, S_IRUGO | S_IWUGO, get_b_bus_req, set_b_bus_req);
+
+static ssize_t
+set_a_clr_err(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+
+	if (!iotg->otg.default_a)
+		return -1;
+	if (count > 2)
+		return -1;
+
+	if (buf[0] == '1') {
+		iotg->hsm.a_clr_err = 1;
+		dev_dbg(lnw->dev, "User request: a_clr_err = 1\n");
+	}
+	if (spin_trylock(&lnw->wq_lock)) {
+		langwell_update_transceiver();
+		spin_unlock(&lnw->wq_lock);
+	}
+	return count;
+}
+static DEVICE_ATTR(a_clr_err, S_IWUGO, NULL, set_a_clr_err);
+
+static struct attribute *inputs_attrs[] = {
+	&dev_attr_a_bus_req.attr,
+	&dev_attr_a_bus_drop.attr,
+	&dev_attr_b_bus_req.attr,
+	&dev_attr_a_clr_err.attr,
+	NULL,
+};
+
+static struct attribute_group debug_dev_attr_group = {
+	.name = "inputs",
+	.attrs = inputs_attrs,
+};
+
+static int langwell_otg_probe(struct pci_dev *pdev,
+		const struct pci_device_id *id)
+{
+	unsigned long		resource, len;
+	void __iomem		*base = NULL;
+	int			retval;
+	u32			val32;
+	struct langwell_otg	*lnw;
+	char			qname[] = "langwell_otg_queue";
+
+	retval = 0;
+	dev_dbg(&pdev->dev, "\notg controller is detected.\n");
+	if (pci_enable_device(pdev) < 0) {
+		retval = -ENODEV;
+		goto done;
+	}
+
+	lnw = kzalloc(sizeof *lnw, GFP_KERNEL);
+	if (lnw == NULL) {
+		retval = -ENOMEM;
+		goto done;
+	}
+	the_transceiver = lnw;
+
+	/* control register: BAR 0 */
+	resource = pci_resource_start(pdev, 0);
+	len = pci_resource_len(pdev, 0);
+	if (!request_mem_region(resource, len, driver_name)) {
+		retval = -EBUSY;
+		goto err;
+	}
+	lnw->region = 1;
+
+	base = ioremap_nocache(resource, len);
+	if (base == NULL) {
+		retval = -EFAULT;
+		goto err;
+	}
+	lnw->iotg.base = base;
+
+	if (!request_mem_region(USBCFG_ADDR, USBCFG_LEN, driver_name)) {
+		retval = -EBUSY;
+		goto err;
+	}
+	lnw->cfg_region = 1;
+
+	/* For the SCCB.USBCFG register */
+	base = ioremap_nocache(USBCFG_ADDR, USBCFG_LEN);
+	if (base == NULL) {
+		retval = -EFAULT;
+		goto err;
+	}
+	lnw->usbcfg = base;
+
+	if (!pdev->irq) {
+		dev_dbg(&pdev->dev, "No IRQ.\n");
+		retval = -ENODEV;
+		goto err;
+	}
+
+	lnw->qwork = create_singlethread_workqueue(qname);
+	if (!lnw->qwork) {
+		dev_dbg(&pdev->dev, "cannot create workqueue %s\n", qname);
+		retval = -ENOMEM;
+		goto err;
+	}
+	INIT_WORK(&lnw->work, langwell_otg_work);
+
+	/* OTG common part */
+	lnw->dev = &pdev->dev;
+	lnw->iotg.otg.dev = lnw->dev;
+	lnw->iotg.otg.label = driver_name;
+	lnw->iotg.otg.set_host = langwell_otg_set_host;
+	lnw->iotg.otg.set_peripheral = langwell_otg_set_peripheral;
+	lnw->iotg.otg.set_power = langwell_otg_set_power;
+	lnw->iotg.otg.set_vbus = langwell_otg_set_vbus;
+	lnw->iotg.otg.start_srp = langwell_otg_start_srp;
+	lnw->iotg.otg.state = OTG_STATE_UNDEFINED;
+
+	if (otg_set_transceiver(&lnw->iotg.otg)) {
+		dev_dbg(lnw->dev, "can't set transceiver\n");
+		retval = -EBUSY;
+		goto err;
+	}
+
+	reset_otg();
+	init_hsm();
+
+	spin_lock_init(&lnw->lock);
+	spin_lock_init(&lnw->wq_lock);
+	INIT_LIST_HEAD(&active_timers);
+	retval = langwell_otg_init_timers(&lnw->iotg.hsm);
+	if (retval) {
+		dev_dbg(&pdev->dev, "Failed to init timers\n");
+		goto err;
+	}
+
+	init_timer(&lnw->hsm_timer);
+	ATOMIC_INIT_NOTIFIER_HEAD(&lnw->iotg.iotg_notifier);
+
+	lnw->iotg_notifier.notifier_call = langwell_otg_iotg_notify;
+
+	retval = intel_mid_otg_register_notifier(&lnw->iotg,
+						&lnw->iotg_notifier);
+	if (retval) {
+		dev_dbg(lnw->dev, "Failed to register notifier\n");
+		goto err;
+	}
+
+	if (request_irq(pdev->irq, otg_irq, IRQF_SHARED,
+				driver_name, lnw) != 0) {
+		dev_dbg(lnw->dev, "request interrupt %d failed\n", pdev->irq);
+		retval = -EBUSY;
+		goto err;
+	}
+
+	/* enable OTGSC int */
+	val32 = OTGSC_DPIE | OTGSC_BSEIE | OTGSC_BSVIE |
+		OTGSC_ASVIE | OTGSC_AVVIE | OTGSC_IDIE | OTGSC_IDPU;
+	writel(val32, lnw->iotg.base + CI_OTGSC);
+
+	retval = device_create_file(&pdev->dev, &dev_attr_registers);
+	if (retval < 0) {
+		dev_dbg(lnw->dev,
+			"Can't register sysfs attribute: %d\n", retval);
+		goto err;
+	}
+
+	retval = device_create_file(&pdev->dev, &dev_attr_hsm);
+	if (retval < 0) {
+		dev_dbg(lnw->dev, "Can't hsm sysfs attribute: %d\n", retval);
+		goto err;
+	}
+
+	retval = sysfs_create_group(&pdev->dev.kobj, &debug_dev_attr_group);
+	if (retval < 0) {
+		dev_dbg(lnw->dev,
+			"Can't register sysfs attr group: %d\n", retval);
+		goto err;
+	}
+
+	if (lnw->iotg.otg.state == OTG_STATE_A_IDLE)
+		langwell_update_transceiver();
+
+	return 0;
+
+err:
+	if (the_transceiver)
+		langwell_otg_remove(pdev);
+done:
+	return retval;
+}
+
+static void langwell_otg_remove(struct pci_dev *pdev)
+{
+	struct langwell_otg *lnw = the_transceiver;
+
+	if (lnw->qwork) {
+		flush_workqueue(lnw->qwork);
+		destroy_workqueue(lnw->qwork);
+	}
+	intel_mid_otg_unregister_notifier(&lnw->iotg, &lnw->iotg_notifier);
+	langwell_otg_free_timers();
+
+	/* disable OTGSC interrupt as OTGSC doesn't change in reset */
+	writel(0, lnw->iotg.base + CI_OTGSC);
+
+	if (pdev->irq)
+		free_irq(pdev->irq, lnw);
+	if (lnw->usbcfg)
+		iounmap(lnw->usbcfg);
+	if (lnw->cfg_region)
+		release_mem_region(USBCFG_ADDR, USBCFG_LEN);
+	if (lnw->iotg.base)
+		iounmap(lnw->iotg.base);
+	if (lnw->region)
+		release_mem_region(pci_resource_start(pdev, 0),
+				pci_resource_len(pdev, 0));
+
+	otg_set_transceiver(NULL);
+	pci_disable_device(pdev);
+	sysfs_remove_group(&pdev->dev.kobj, &debug_dev_attr_group);
+	device_remove_file(&pdev->dev, &dev_attr_hsm);
+	device_remove_file(&pdev->dev, &dev_attr_registers);
+	kfree(lnw);
+	lnw = NULL;
+}
+
+static void transceiver_suspend(struct pci_dev *pdev)
+{
+	pci_save_state(pdev);
+	pci_set_power_state(pdev, PCI_D3hot);
+	langwell_otg_phy_low_power(1);
+}
+
+static int langwell_otg_suspend(struct pci_dev *pdev, pm_message_t message)
+{
+	struct langwell_otg		*lnw = the_transceiver;
+	struct intel_mid_otg_xceiv	*iotg = &lnw->iotg;
+	int				ret = 0;
+
+	/* Disbale OTG interrupts */
+	langwell_otg_intr(0);
+
+	if (pdev->irq)
+		free_irq(pdev->irq, lnw);
+
+	/* Prevent more otg_work */
+	flush_workqueue(lnw->qwork);
+	destroy_workqueue(lnw->qwork);
+	lnw->qwork = NULL;
+
+	/* start actions */
+	switch (iotg->otg.state) {
+	case OTG_STATE_A_WAIT_VFALL:
+		iotg->otg.state = OTG_STATE_A_IDLE;
+	case OTG_STATE_A_IDLE:
+	case OTG_STATE_B_IDLE:
+	case OTG_STATE_A_VBUS_ERR:
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_A_WAIT_VRISE:
+		langwell_otg_del_timer(a_wait_vrise_tmr);
+		iotg->hsm.a_srp_det = 0;
+
+		/* Turn off VBus */
+		iotg->otg.set_vbus(&iotg->otg, false);
+		iotg->otg.state = OTG_STATE_A_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_A_WAIT_BCON:
+		del_timer_sync(&lnw->hsm_timer);
+		if (lnw->iotg.stop_host)
+			lnw->iotg.stop_host(&lnw->iotg);
+		else
+			dev_dbg(&pdev->dev, "host driver has been removed.\n");
+
+		iotg->hsm.a_srp_det = 0;
+
+		/* Turn off VBus */
+		iotg->otg.set_vbus(&iotg->otg, false);
+		iotg->otg.state = OTG_STATE_A_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_A_HOST:
+		if (lnw->iotg.stop_host)
+			lnw->iotg.stop_host(&lnw->iotg);
+		else
+			dev_dbg(&pdev->dev, "host driver has been removed.\n");
+
+		iotg->hsm.a_srp_det = 0;
+
+		/* Turn off VBus */
+		iotg->otg.set_vbus(&iotg->otg, false);
+
+		iotg->otg.state = OTG_STATE_A_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_A_SUSPEND:
+		langwell_otg_del_timer(a_aidl_bdis_tmr);
+		langwell_otg_HABA(0);
+		if (lnw->iotg.stop_host)
+			lnw->iotg.stop_host(&lnw->iotg);
+		else
+			dev_dbg(lnw->dev, "host driver has been removed.\n");
+		iotg->hsm.a_srp_det = 0;
+
+		/* Turn off VBus */
+		iotg->otg.set_vbus(&iotg->otg, false);
+		iotg->otg.state = OTG_STATE_A_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_A_PERIPHERAL:
+		del_timer_sync(&lnw->hsm_timer);
+
+		if (lnw->iotg.stop_peripheral)
+			lnw->iotg.stop_peripheral(&lnw->iotg);
+		else
+			dev_dbg(&pdev->dev,
+				"client driver has been removed.\n");
+		iotg->hsm.a_srp_det = 0;
+
+		/* Turn off VBus */
+		iotg->otg.set_vbus(&iotg->otg, false);
+		iotg->otg.state = OTG_STATE_A_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_B_HOST:
+		if (lnw->iotg.stop_host)
+			lnw->iotg.stop_host(&lnw->iotg);
+		else
+			dev_dbg(&pdev->dev, "host driver has been removed.\n");
+		iotg->hsm.b_bus_req = 0;
+		iotg->otg.state = OTG_STATE_B_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		if (lnw->iotg.stop_peripheral)
+			lnw->iotg.stop_peripheral(&lnw->iotg);
+		else
+			dev_dbg(&pdev->dev,
+				"client driver has been removed.\n");
+		iotg->otg.state = OTG_STATE_B_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	case OTG_STATE_B_WAIT_ACON:
+		/* delete hsm timer for b_ase0_brst_tmr */
+		del_timer_sync(&lnw->hsm_timer);
+
+		langwell_otg_HAAR(0);
+
+		if (lnw->iotg.stop_host)
+			lnw->iotg.stop_host(&lnw->iotg);
+		else
+			dev_dbg(&pdev->dev, "host driver has been removed.\n");
+		iotg->hsm.b_bus_req = 0;
+		iotg->otg.state = OTG_STATE_B_IDLE;
+		transceiver_suspend(pdev);
+		break;
+	default:
+		dev_dbg(lnw->dev, "error state before suspend\n");
+		break;
+	}
+
+	return ret;
+}
+
+static void transceiver_resume(struct pci_dev *pdev)
+{
+	pci_restore_state(pdev);
+	pci_set_power_state(pdev, PCI_D0);
+}
+
+static int langwell_otg_resume(struct pci_dev *pdev)
+{
+	struct langwell_otg	*lnw = the_transceiver;
+	int			ret = 0;
+
+	transceiver_resume(pdev);
+
+	lnw->qwork = create_singlethread_workqueue("langwell_otg_queue");
+	if (!lnw->qwork) {
+		dev_dbg(&pdev->dev, "cannot create langwell otg workqueuen");
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	if (request_irq(pdev->irq, otg_irq, IRQF_SHARED,
+				driver_name, lnw) != 0) {
+		dev_dbg(&pdev->dev, "request interrupt %d failed\n", pdev->irq);
+		ret = -EBUSY;
+		goto error;
+	}
+
+	/* enable OTG interrupts */
+	langwell_otg_intr(1);
+
+	update_hsm();
+
+	langwell_update_transceiver();
+
+	return ret;
+error:
+	langwell_otg_intr(0);
+	transceiver_suspend(pdev);
+	return ret;
+}
+
+static int __init langwell_otg_init(void)
+{
+	return pci_register_driver(&otg_pci_driver);
+}
+module_init(langwell_otg_init);
+
+static void __exit langwell_otg_cleanup(void)
+{
+	pci_unregister_driver(&otg_pci_driver);
+}
+module_exit(langwell_otg_cleanup);
diff --git a/include/linux/usb/langwell_otg.h b/include/linux/usb/langwell_otg.h
new file mode 100644
index 0000000..a6562f1
--- /dev/null
+++ b/include/linux/usb/langwell_otg.h
@@ -0,0 +1,139 @@
+/*
+ * Intel Langwell USB OTG transceiver driver
+ * Copyright (C) 2008, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef __LANGWELL_OTG_H
+#define __LANGWELL_OTG_H
+
+#include <linux/usb/intel_mid_otg.h>
+
+#define CI_USBCMD		0x30
+#	define USBCMD_RST		BIT(1)
+#	define USBCMD_RS		BIT(0)
+#define CI_USBSTS		0x34
+#	define USBSTS_SLI		BIT(8)
+#	define USBSTS_URI		BIT(6)
+#	define USBSTS_PCI		BIT(2)
+#define CI_PORTSC1		0x74
+#	define PORTSC_PP		BIT(12)
+#	define PORTSC_LS		(BIT(11) | BIT(10))
+#	define PORTSC_SUSP		BIT(7)
+#	define PORTSC_CCS		BIT(0)
+#define CI_HOSTPC1		0xb4
+#	define HOSTPC1_PHCD		BIT(22)
+#define CI_OTGSC		0xf4
+#	define OTGSC_DPIE		BIT(30)
+#	define OTGSC_1MSE		BIT(29)
+#	define OTGSC_BSEIE		BIT(28)
+#	define OTGSC_BSVIE		BIT(27)
+#	define OTGSC_ASVIE		BIT(26)
+#	define OTGSC_AVVIE		BIT(25)
+#	define OTGSC_IDIE		BIT(24)
+#	define OTGSC_DPIS		BIT(22)
+#	define OTGSC_1MSS		BIT(21)
+#	define OTGSC_BSEIS		BIT(20)
+#	define OTGSC_BSVIS		BIT(19)
+#	define OTGSC_ASVIS		BIT(18)
+#	define OTGSC_AVVIS		BIT(17)
+#	define OTGSC_IDIS		BIT(16)
+#	define OTGSC_DPS		BIT(14)
+#	define OTGSC_1MST		BIT(13)
+#	define OTGSC_BSE		BIT(12)
+#	define OTGSC_BSV		BIT(11)
+#	define OTGSC_ASV		BIT(10)
+#	define OTGSC_AVV		BIT(9)
+#	define OTGSC_ID			BIT(8)
+#	define OTGSC_HABA		BIT(7)
+#	define OTGSC_HADP		BIT(6)
+#	define OTGSC_IDPU		BIT(5)
+#	define OTGSC_DP			BIT(4)
+#	define OTGSC_OT			BIT(3)
+#	define OTGSC_HAAR		BIT(2)
+#	define OTGSC_VC			BIT(1)
+#	define OTGSC_VD			BIT(0)
+#	define OTGSC_INTEN_MASK		(0x7f << 24)
+#	define OTGSC_INT_MASK		(0x5f << 24)
+#	define OTGSC_INTSTS_MASK	(0x7f << 16)
+#define CI_USBMODE		0xf8
+#	define USBMODE_CM		(BIT(1) | BIT(0))
+#	define USBMODE_IDLE		0
+#	define USBMODE_DEVICE		0x2
+#	define USBMODE_HOST		0x3
+#define USBCFG_ADDR			0xff10801c
+#define USBCFG_LEN			4
+#	define USBCFG_VBUSVAL		BIT(14)
+#	define USBCFG_AVALID		BIT(13)
+#	define USBCFG_BVALID		BIT(12)
+#	define USBCFG_SESEND		BIT(11)
+
+#define INTR_DUMMY_MASK (USBSTS_SLI | USBSTS_URI | USBSTS_PCI)
+
+enum langwell_otg_timer_type {
+	TA_WAIT_VRISE_TMR,
+	TA_WAIT_BCON_TMR,
+	TA_AIDL_BDIS_TMR,
+	TB_ASE0_BRST_TMR,
+	TB_SE0_SRP_TMR,
+	TB_SRP_INIT_TMR,
+	TB_SRP_FAIL_TMR,
+	TB_BUS_SUSPEND_TMR
+};
+
+#define TA_WAIT_VRISE	100
+#define TA_WAIT_BCON	30000
+#define TA_AIDL_BDIS	15000
+#define TB_ASE0_BRST	5000
+#define TB_SE0_SRP	2
+#define TB_SRP_INIT	100
+#define TB_SRP_FAIL	5500
+#define TB_BUS_SUSPEND	500
+
+struct langwell_otg_timer {
+	unsigned long expires;	/* Number of count increase to timeout */
+	unsigned long count;	/* Tick counter */
+	void (*function)(unsigned long);	/* Timeout function */
+	unsigned long data;	/* Data passed to function */
+	struct list_head list;
+};
+
+struct langwell_otg {
+	struct intel_mid_otg_xceiv	iotg;
+	struct device			*dev;
+
+	void __iomem			*usbcfg;	/* SCCBUSB config Reg */
+
+	unsigned			region;
+	unsigned			cfg_region;
+
+	struct work_struct		work;
+	struct workqueue_struct		*qwork;
+	struct timer_list		hsm_timer;
+
+	spinlock_t			lock;
+	spinlock_t			wq_lock;
+
+	struct notifier_block		iotg_notifier;
+};
+
+static inline
+struct langwell_otg *mid_xceiv_to_lnw(struct intel_mid_otg_xceiv *iotg)
+{
+	return container_of(iotg, struct langwell_otg, iotg);
+}
+
+#endif /* __LANGWELL_OTG_H__ */