--- /dev/null
+/*
+ * 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/notifier.h>
+#include <asm/ipc_defs.h>
+#include <linux/delay.h>
+#include "../core/hcd.h"
+
+#include <linux/usb/langwell_otg.h>
+
+#define        DRIVER_DESC             "Intel Langwell USB OTG transceiver driver"
+#define        DRIVER_VERSION          "3.0.0.32L.0002"
+
+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);
+       timer->function = function;
+       timer->expires = expires;
+       timer->data = data;
+       return timer;
+}
+
+static struct langwell_otg_timer *a_wait_vrise_tmr, *a_wait_bcon_tmr,
+       *a_aidl_bdis_tmr, *b_ase0_brst_tmr, *b_se0_srp_tmr, *b_srp_res_tmr,
+       *b_bus_suspend_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()
+{
+       otg_dbg("transceiver driver is notified\n");
+       queue_work(the_transceiver->qwork, &the_transceiver->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 void langwell_otg_drv_vbus(int on)
+{
+       struct ipc_pmic_reg_data        pmic_data = {0};
+       struct ipc_pmic_reg_data        battery_data;
+
+       /* Check if battery is attached or not */
+       battery_data.pmic_reg_data[0].register_address = 0xd2;
+       battery_data.ioc = 0;
+       battery_data.num_entries = 1;
+       if (ipc_pmic_register_read(&battery_data)) {
+               otg_dbg("Failed to read PMIC register 0xd2.\n");
+               return;
+       }
+
+       if ((battery_data.pmic_reg_data[0].value & 0x20) == 0) {
+               otg_dbg("no battery attached\n");
+               return;
+       }
+
+       /* Workaround for battery attachment issue */
+       if (battery_data.pmic_reg_data[0].value == 0x34) {
+               otg_dbg("battery \n");
+               return;
+       }
+
+       otg_dbg("battery attached\n");
+
+       pmic_data.ioc = 0;
+       pmic_data.pmic_reg_data[0].register_address = 0xD4;
+       pmic_data.num_entries = 1;
+       if (on)
+               pmic_data.pmic_reg_data[0].value = 0x20;
+       else
+               pmic_data.pmic_reg_data[0].value = 0xc0;
+
+       if (ipc_pmic_register_write(&pmic_data, TRUE))
+               otg_dbg("Failed to write PMIC.\n");
+
+}
+
+/* charge vbus or discharge vbus through a resistor to ground */
+static void langwell_otg_chrg_vbus(int on)
+{
+
+       u32     val;
+
+       val = readl(the_transceiver->regs + CI_OTGSC);
+
+       if (on)
+               writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_VC,
+                               the_transceiver->regs + CI_OTGSC);
+       else
+               writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_VD,
+                               the_transceiver->regs + CI_OTGSC);
+
+}
+
+/* Start SRP */
+static int langwell_otg_start_srp(struct otg_transceiver *otg)
+{
+       u32     val;
+
+       otg_dbg("Start SRP ->\n");
+
+       val = readl(the_transceiver->regs + CI_OTGSC);
+
+       writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_HADP,
+               the_transceiver->regs + CI_OTGSC);
+
+       /* Check if the data plus is finished or not */
+       msleep(8);
+       val = readl(the_transceiver->regs + CI_OTGSC);
+       if (val & (OTGSC_HADP | OTGSC_DP))
+               otg_dbg("DataLine SRP Error\n");
+
+       /* FIXME: VBus SRP */
+
+       return 0;
+}
+
+
+/* stop SOF via bus_suspend */
+static void langwell_otg_loc_sof(int on)
+{
+       struct usb_hcd  *hcd;
+       int             err;
+
+       otg_dbg("loc_sof -> %d\n", on);
+
+       hcd = bus_to_hcd(the_transceiver->otg.host);
+       if (on)
+               err = hcd->driver->bus_resume(hcd);
+       else
+               err = hcd->driver->bus_suspend(hcd);
+
+       if (err)
+               otg_dbg("Failed to resume/suspend bus - %d\n", err);
+}
+
+static void langwell_otg_phy_low_power(int on)
+{
+       u32     val;
+
+       otg_dbg("phy low power mode-> %d\n", on);
+
+       val = readl(the_transceiver->regs + CI_HOSTPC1);
+       if (on)
+               writel(val | HOSTPC1_PHCD, the_transceiver->regs + CI_HOSTPC1);
+       else
+               writel(val & ~HOSTPC1_PHCD, the_transceiver->regs + CI_HOSTPC1);
+}
+
+/* Enable/Disable OTG interrupt */
+static void langwell_otg_intr(int on)
+{
+       u32 val;
+
+       otg_dbg("interrupt -> %d\n", on);
+
+       val = readl(the_transceiver->regs + CI_OTGSC);
+       if (on) {
+               val = val | (OTGSC_INTEN_MASK | OTGSC_IDPU);
+               writel(val, the_transceiver->regs + CI_OTGSC);
+       } else {
+               val = val & ~(OTGSC_INTEN_MASK | OTGSC_IDPU);
+               writel(val, the_transceiver->regs + CI_OTGSC);
+       }
+}
+
+/* set HAAR: Hardware Assist Auto-Reset */
+static void langwell_otg_HAAR(int on)
+{
+       u32     val;
+
+       otg_dbg("HAAR -> %d\n", on);
+
+       val = readl(the_transceiver->regs + CI_OTGSC);
+       if (on)
+               writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_HAAR,
+                               the_transceiver->regs + CI_OTGSC);
+       else
+               writel((val & ~OTGSC_INTSTS_MASK) & ~OTGSC_HAAR,
+                               the_transceiver->regs + CI_OTGSC);
+}
+
+/* set HABA: Hardware Assist B-Disconnect to A-Connect */
+static void langwell_otg_HABA(int on)
+{
+       u32     val;
+
+       otg_dbg("HABA -> %d\n", on);
+
+       val = readl(the_transceiver->regs + CI_OTGSC);
+       if (on)
+               writel((val & ~OTGSC_INTSTS_MASK) | OTGSC_HABA,
+                               the_transceiver->regs + CI_OTGSC);
+       else
+               writel((val & ~OTGSC_INTSTS_MASK) & ~OTGSC_HABA,
+                               the_transceiver->regs + CI_OTGSC);
+}
+
+static int langwell_otg_check_se0_srp(int on)
+{
+       u32 val;
+
+       int delay_time = TB_SE0_SRP * 10; /* step is 100us */
+
+       otg_dbg("check_se0_srp -> \n");
+
+       do {
+               udelay(100);
+               if (!delay_time--)
+                       break;
+               val = readl(the_transceiver->regs + CI_PORTSC1);
+               val &= PORTSC_LS;
+       } while (!val);
+
+       otg_dbg("check_se0_srp <- \n");
+       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)
+{
+       switch (indicator) {
+       case 2:
+       case 4:
+       case 6:
+       case 7:
+               printk(KERN_ERR "OTG:NSF-%lu - deivce not responding\n",
+                               indicator);
+               break;
+       case 3:
+               printk(KERN_ERR "OTG:NSF-%lu - deivce not supported\n",
+                               indicator);
+               break;
+       default:
+               printk(KERN_ERR "Do not have this kind of NSF\n");
+               break;
+       }
+}
+
+/* Initialize timers */
+static void 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);
+       a_wait_bcon_tmr = otg_timer_initializer(&set_tmout, TA_WAIT_BCON,
+                               (unsigned long)&hsm->a_wait_bcon_tmout);
+       a_aidl_bdis_tmr = otg_timer_initializer(&set_tmout, TA_AIDL_BDIS,
+                               (unsigned long)&hsm->a_aidl_bdis_tmout);
+       b_ase0_brst_tmr = otg_timer_initializer(&set_tmout, TB_ASE0_BRST,
+                               (unsigned long)&hsm->b_ase0_brst_tmout);
+       b_se0_srp_tmr = otg_timer_initializer(&set_tmout, TB_SE0_SRP,
+                               (unsigned long)&hsm->b_se0_srp);
+       b_srp_res_tmr = otg_timer_initializer(&set_tmout, TB_SRP_RES,
+                               (unsigned long)&hsm->b_srp_res_tmout);
+       b_bus_suspend_tmr = otg_timer_initializer(&set_tmout, TB_BUS_SUSPEND,
+                               (unsigned long)&hsm->b_bus_suspend_tmout);
+}
+
+/* Free timers */
+static void langwell_otg_free_timers(void)
+{
+       kfree(a_wait_vrise_tmr);
+       kfree(a_wait_bcon_tmr);
+       kfree(a_aidl_bdis_tmr);
+       kfree(b_ase0_brst_tmr);
+       kfree(b_se0_srp_tmr);
+       kfree(b_srp_res_tmr);
+       kfree(b_bus_suspend_tmr);
+}
+
+/* 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;
+       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(the_transceiver->regs + CI_OTGSC);
+               writel(val32 | OTGSC_1MSE, the_transceiver->regs + 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_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(the_transceiver->regs + CI_OTGSC);
+               writel(val32 & ~OTGSC_1MSE, the_transceiver->regs + CI_OTGSC);
+       }
+}
+
+/* Reduce timer count by 1, and find timeout conditions.*/
+static int langwell_otg_tick_timer(u32 *int_sts)
+{
+       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)) {
+               otg_dbg("tick timer: disable 1ms int\n");
+               *int_sts = *int_sts & ~OTGSC_1MSE;
+       }
+       return expired;
+}
+
+static void reset_otg(void)
+{
+       u32     val;
+       int     delay_time = 1000;
+
+       otg_dbg("reseting OTG controller ...\n");
+       val = readl(the_transceiver->regs + CI_USBCMD);
+       writel(val | USBCMD_RST, the_transceiver->regs + CI_USBCMD);
+       do {
+               udelay(100);
+               if (!delay_time--)
+                       otg_dbg("reset timeout\n");
+               val = readl(the_transceiver->regs + CI_USBCMD);
+               val &= USBCMD_RST;
+       } while (val != 0);
+       otg_dbg("reset done.\n");
+}
+
+static void set_host_mode(void)
+{
+       u32     val;
+
+       reset_otg();
+       val = readl(the_transceiver->regs + CI_USBMODE);
+       val = (val & (~USBMODE_CM)) | USBMODE_HOST;
+       writel(val, the_transceiver->regs + CI_USBMODE);
+}
+
+static void set_client_mode(void)
+{
+       u32     val;
+
+       reset_otg();
+       val = readl(the_transceiver->regs + CI_USBMODE);
+       val = (val & (~USBMODE_CM)) | USBMODE_DEVICE;
+       writel(val, the_transceiver->regs + CI_USBMODE);
+}
+
+static void init_hsm(void)
+{
+       struct langwell_otg     *langwell = the_transceiver;
+       u32                     val32;
+
+       /* read OTGSC after reset */
+       val32 = readl(langwell->regs + CI_OTGSC);
+       otg_dbg("%s: OTGSC init value = 0x%x\n", __func__, val32);
+
+       /* set init state */
+       if (val32 & OTGSC_ID) {
+               langwell->hsm.id = 1;
+               langwell->otg.default_a = 0;
+               set_client_mode();
+               langwell->otg.state = OTG_STATE_B_IDLE;
+               langwell_otg_drv_vbus(0);
+       } else {
+               langwell->hsm.id = 0;
+               langwell->otg.default_a = 1;
+               set_host_mode();
+               langwell->otg.state = OTG_STATE_A_IDLE;
+       }
+
+       /* set session indicator */
+       if (val32 & OTGSC_BSE)
+               langwell->hsm.b_sess_end = 1;
+       if (val32 & OTGSC_BSV)
+               langwell->hsm.b_sess_vld = 1;
+       if (val32 & OTGSC_ASV)
+               langwell->hsm.a_sess_vld = 1;
+       if (val32 & OTGSC_AVV)
+               langwell->hsm.a_vbus_vld = 1;
+
+       /* defautly power the bus */
+       langwell->hsm.a_bus_req = 1;
+       langwell->hsm.a_bus_drop = 0;
+       /* defautly don't request bus as B device */
+       langwell->hsm.b_bus_req = 0;
+       /* no system error */
+       langwell->hsm.a_clr_err = 0;
+}
+
+static irqreturn_t otg_dummy_irq(int irq, void *_dev)
+{
+       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 (the_transceiver->hsm.b_conn) {
+               the_transceiver->hsm.b_conn = 0;
+               if (spin_trylock(&the_transceiver->wq_lock)) {
+                       queue_work(the_transceiver->qwork,
+                               &the_transceiver->work);
+                       spin_unlock(&the_transceiver->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 *langwell = _dev;
+       u32     int_sts, int_en;
+       u32     int_mask = 0;
+       int     flag = 0;
+
+       int_sts = readl(langwell->regs + 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) {
+               otg_dbg("%s: id change int\n", __func__);
+               langwell->hsm.id = (int_sts & OTGSC_ID) ? 1 : 0;
+               flag = 1;
+       }
+       if (int_mask & OTGSC_DPIS) {
+               otg_dbg("%s: data pulse int\n", __func__);
+               langwell->hsm.a_srp_det = (int_sts & OTGSC_DPS) ? 1 : 0;
+               flag = 1;
+       }
+       if (int_mask & OTGSC_BSEIS) {
+               otg_dbg("%s: b session end int\n", __func__);
+               langwell->hsm.b_sess_end = (int_sts & OTGSC_BSE) ? 1 : 0;
+               flag = 1;
+       }
+       if (int_mask & OTGSC_BSVIS) {
+               otg_dbg("%s: b session valid int\n", __func__);
+               langwell->hsm.b_sess_vld = (int_sts & OTGSC_BSV) ? 1 : 0;
+               flag = 1;
+       }
+       if (int_mask & OTGSC_ASVIS) {
+               otg_dbg("%s: a session valid int\n", __func__);
+               langwell->hsm.a_sess_vld = (int_sts & OTGSC_ASV) ? 1 : 0;
+               flag = 1;
+       }
+       if (int_mask & OTGSC_AVVIS) {
+               otg_dbg("%s: a vbus valid int\n", __func__);
+               langwell->hsm.a_vbus_vld = (int_sts & OTGSC_AVV) ? 1 : 0;
+               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,
+                       langwell->regs + CI_OTGSC);
+       if (flag)
+               queue_work(langwell->qwork, &langwell->work);
+
+       return IRQ_HANDLED;
+}
+
+static void langwell_otg_work(struct work_struct *work)
+{
+       struct langwell_otg *langwell = container_of(work,
+                                       struct langwell_otg, work);
+       int     retval;
+
+       otg_dbg("%s: old state = %s\n", __func__,
+                       state_string(langwell->otg.state));
+
+       switch (langwell->otg.state) {
+       case OTG_STATE_UNDEFINED:
+       case OTG_STATE_B_IDLE:
+               if (!langwell->hsm.id) {
+                       langwell_otg_del_timer(b_srp_res_tmr);
+                       langwell->otg.default_a = 1;
+                       langwell->hsm.a_srp_det = 0;
+
+                       langwell_otg_chrg_vbus(0);
+                       langwell_otg_drv_vbus(0);
+
+                       set_host_mode();
+                       langwell->otg.state = OTG_STATE_A_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.b_srp_res_tmout) {
+                       langwell->hsm.b_srp_res_tmout = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       langwell_otg_nsf_msg(6);
+               } else if (langwell->hsm.b_sess_vld) {
+                       langwell_otg_del_timer(b_srp_res_tmr);
+                       langwell->hsm.b_sess_end = 0;
+                       langwell->hsm.a_bus_suspend = 0;
+
+                       langwell_otg_chrg_vbus(0);
+                       if (langwell->client_ops) {
+                               langwell->client_ops->resume(langwell->pdev);
+                               langwell->otg.state = OTG_STATE_B_PERIPHERAL;
+                       } else
+                               otg_dbg("client driver not loaded.\n");
+
+               } else if (langwell->hsm.b_bus_req &&
+                               (langwell->hsm.b_sess_end)) {
+                       /* workaround for b_se0_srp detection */
+                       retval = langwell_otg_check_se0_srp(0);
+                       if (retval) {
+                               langwell->hsm.b_bus_req = 0;
+                               otg_dbg("LS is not SE0, try again later\n");
+                       } else {
+                               /* Start SRP */
+                               langwell_otg_start_srp(&langwell->otg);
+                               langwell_otg_add_timer(b_srp_res_tmr);
+                       }
+               }
+               break;
+       case OTG_STATE_B_SRP_INIT:
+               if (!langwell->hsm.id) {
+                       langwell->otg.default_a = 1;
+                       langwell->hsm.a_srp_det = 0;
+
+                       langwell_otg_drv_vbus(0);
+                       langwell_otg_chrg_vbus(0);
+
+                       langwell->otg.state = OTG_STATE_A_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.b_sess_vld) {
+                       langwell_otg_chrg_vbus(0);
+                       if (langwell->client_ops) {
+                               langwell->client_ops->resume(langwell->pdev);
+                               langwell->otg.state = OTG_STATE_B_PERIPHERAL;
+                       } else
+                               otg_dbg("client driver not loaded.\n");
+               }
+               break;
+       case OTG_STATE_B_PERIPHERAL:
+               if (!langwell->hsm.id) {
+                       langwell->otg.default_a = 1;
+                       langwell->hsm.a_srp_det = 0;
+
+                       langwell_otg_drv_vbus(0);
+                       langwell_otg_chrg_vbus(0);
+                       set_host_mode();
+
+                       if (langwell->client_ops) {
+                               langwell->client_ops->suspend(langwell->pdev,
+                                       PMSG_FREEZE);
+                       } else
+                               otg_dbg("client driver has been removed.\n");
+
+                       langwell->otg.state = OTG_STATE_A_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (!langwell->hsm.b_sess_vld) {
+                       langwell->hsm.b_hnp_enable = 0;
+
+                       if (langwell->client_ops) {
+                               langwell->client_ops->suspend(langwell->pdev,
+                                       PMSG_FREEZE);
+                       } else
+                               otg_dbg("client driver has been removed.\n");
+
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+               } else if (langwell->hsm.b_bus_req && langwell->hsm.b_hnp_enable
+                       && langwell->hsm.a_bus_suspend) {
+
+                       if (langwell->client_ops) {
+                               langwell->client_ops->suspend(langwell->pdev,
+                                       PMSG_FREEZE);
+                       } else
+                               otg_dbg("client driver has been removed.\n");
+
+                       langwell_otg_HAAR(1);
+                       langwell->hsm.a_conn = 0;
+
+                       if (langwell->host_ops) {
+                               langwell->host_ops->probe(langwell->pdev,
+                                       langwell->host_ops->id_table);
+                               langwell->otg.state = OTG_STATE_B_WAIT_ACON;
+                       } else
+                               otg_dbg("host driver not loaded.\n");
+
+                       langwell->hsm.a_bus_resume = 0;
+                       langwell->hsm.b_ase0_brst_tmout = 0;
+                       langwell_otg_add_timer(b_ase0_brst_tmr);
+               }
+               break;
+
+       case OTG_STATE_B_WAIT_ACON:
+               if (!langwell->hsm.id) {
+                       langwell_otg_del_timer(b_ase0_brst_tmr);
+                       langwell->otg.default_a = 1;
+                       langwell->hsm.a_srp_det = 0;
+
+                       langwell_otg_drv_vbus(0);
+                       langwell_otg_chrg_vbus(0);
+                       set_host_mode();
+
+                       langwell_otg_HAAR(0);
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell->otg.state = OTG_STATE_A_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (!langwell->hsm.b_sess_vld) {
+                       langwell_otg_del_timer(b_ase0_brst_tmr);
+                       langwell->hsm.b_hnp_enable = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       langwell_otg_chrg_vbus(0);
+                       langwell_otg_HAAR(0);
+
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+               } else if (langwell->hsm.a_conn) {
+                       langwell_otg_del_timer(b_ase0_brst_tmr);
+                       langwell_otg_HAAR(0);
+                       langwell->otg.state = OTG_STATE_B_HOST;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.a_bus_resume ||
+                               langwell->hsm.b_ase0_brst_tmout) {
+                       langwell_otg_del_timer(b_ase0_brst_tmr);
+                       langwell_otg_HAAR(0);
+                       langwell_otg_nsf_msg(7);
+
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+
+                       langwell->hsm.a_bus_suspend = 0;
+                       langwell->hsm.b_bus_req = 0;
+
+                       if (langwell->client_ops)
+                               langwell->client_ops->resume(langwell->pdev);
+                       else
+                               otg_dbg("client driver not loaded.\n");
+
+                       langwell->otg.state = OTG_STATE_B_PERIPHERAL;
+               }
+               break;
+
+       case OTG_STATE_B_HOST:
+               if (!langwell->hsm.id) {
+                       langwell->otg.default_a = 1;
+                       langwell->hsm.a_srp_det = 0;
+
+                       langwell_otg_drv_vbus(0);
+                       langwell_otg_chrg_vbus(0);
+                       set_host_mode();
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell->otg.state = OTG_STATE_A_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (!langwell->hsm.b_sess_vld) {
+                       langwell->hsm.b_hnp_enable = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       langwell_otg_chrg_vbus(0);
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+               } else if ((!langwell->hsm.b_bus_req) ||
+                               (!langwell->hsm.a_conn)) {
+                       langwell->hsm.b_bus_req = 0;
+                       langwell_otg_loc_sof(0);
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+
+                       langwell->hsm.a_bus_suspend = 0;
+
+                       if (langwell->client_ops)
+                               langwell->client_ops->resume(langwell->pdev);
+                       else
+                               otg_dbg("client driver not loaded.\n");
+
+                       langwell->otg.state = OTG_STATE_B_PERIPHERAL;
+               }
+               break;
+
+       case OTG_STATE_A_IDLE:
+               langwell->otg.default_a = 1;
+               if (langwell->hsm.id) {
+                       langwell->otg.default_a = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       langwell_otg_drv_vbus(0);
+                       langwell_otg_chrg_vbus(0);
+
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.a_sess_vld) {
+                       langwell_otg_drv_vbus(1);
+                       langwell->hsm.a_srp_det = 1;
+                       langwell->hsm.a_wait_vrise_tmout = 0;
+                       langwell_otg_add_timer(a_wait_vrise_tmr);
+                       langwell->otg.state = OTG_STATE_A_WAIT_VRISE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (!langwell->hsm.a_bus_drop &&
+                       (langwell->hsm.a_srp_det || langwell->hsm.a_bus_req)) {
+                       langwell_otg_drv_vbus(1);
+                       langwell->hsm.a_wait_vrise_tmout = 0;
+                       langwell_otg_add_timer(a_wait_vrise_tmr);
+                       langwell->otg.state = OTG_STATE_A_WAIT_VRISE;
+                       queue_work(langwell->qwork, &langwell->work);
+               }
+               break;
+       case OTG_STATE_A_WAIT_VRISE:
+               if (langwell->hsm.id) {
+                       langwell_otg_del_timer(a_wait_vrise_tmr);
+                       langwell->hsm.b_bus_req = 0;
+                       langwell->otg.default_a = 0;
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+               } else if (langwell->hsm.a_vbus_vld) {
+                       langwell_otg_del_timer(a_wait_vrise_tmr);
+                       if (langwell->host_ops)
+                               langwell->host_ops->probe(langwell->pdev,
+                                               langwell->host_ops->id_table);
+                       else
+                               otg_dbg("host driver not loaded.\n");
+                       langwell->hsm.b_conn = 0;
+                       langwell->hsm.a_set_b_hnp_en = 0;
+                       langwell->hsm.a_wait_bcon_tmout = 0;
+                       langwell_otg_add_timer(a_wait_bcon_tmr);
+                       langwell->otg.state = OTG_STATE_A_WAIT_BCON;
+               } else if (langwell->hsm.a_wait_vrise_tmout) {
+                       if (langwell->hsm.a_vbus_vld) {
+                               if (langwell->host_ops)
+                                       langwell->host_ops->probe(
+                                               langwell->pdev,
+                                               langwell->host_ops->id_table);
+                               else
+                                       otg_dbg("host driver not loaded.\n");
+                               langwell->hsm.b_conn = 0;
+                               langwell->hsm.a_set_b_hnp_en = 0;
+                               langwell->hsm.a_wait_bcon_tmout = 0;
+                               langwell_otg_add_timer(a_wait_bcon_tmr);
+                               langwell->otg.state = OTG_STATE_A_WAIT_BCON;
+                       } else {
+                               langwell_otg_drv_vbus(0);
+                               langwell->otg.state = OTG_STATE_A_VBUS_ERR;
+                       }
+               }
+               break;
+       case OTG_STATE_A_WAIT_BCON:
+               if (langwell->hsm.id) {
+                       langwell_otg_del_timer(a_wait_bcon_tmr);
+
+                       langwell->otg.default_a = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (!langwell->hsm.a_vbus_vld) {
+                       langwell_otg_del_timer(a_wait_bcon_tmr);
+
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_VBUS_ERR;
+               } else if (langwell->hsm.a_bus_drop ||
+                               (langwell->hsm.a_wait_bcon_tmout &&
+                               !langwell->hsm.a_bus_req)) {
+                       langwell_otg_del_timer(a_wait_bcon_tmr);
+
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_WAIT_VFALL;
+               } else if (langwell->hsm.b_conn) {
+                       langwell_otg_del_timer(a_wait_bcon_tmr);
+
+                       langwell->hsm.a_suspend_req = 0;
+                       langwell->otg.state = OTG_STATE_A_HOST;
+                       if (!langwell->hsm.a_bus_req &&
+                               langwell->hsm.a_set_b_hnp_en) {
+                               /* It is not safe enough to do a fast
+                                * transistion from A_WAIT_BCON to
+                                * A_SUSPEND */
+                               msleep(10000);
+                               if (langwell->hsm.a_bus_req)
+                                       break;
+
+                               if (request_irq(langwell->pdev->irq,
+                                       otg_dummy_irq, IRQF_SHARED,
+                                       driver_name, langwell->regs) != 0) {
+                                       otg_dbg("request interrupt %d fail\n",
+                                       langwell->pdev->irq);
+                               }
+
+                               langwell_otg_HABA(1);
+                               langwell->hsm.b_bus_resume = 0;
+                               langwell->hsm.a_aidl_bdis_tmout = 0;
+                               langwell_otg_add_timer(a_aidl_bdis_tmr);
+
+                               langwell_otg_loc_sof(0);
+                               langwell->otg.state = OTG_STATE_A_SUSPEND;
+                       } else if (!langwell->hsm.a_bus_req &&
+                               !langwell->hsm.a_set_b_hnp_en) {
+                               struct pci_dev *pdev = langwell->pdev;
+                               if (langwell->host_ops)
+                                       langwell->host_ops->remove(pdev);
+                               else
+                                       otg_dbg("host driver removed.\n");
+                               langwell_otg_drv_vbus(0);
+                               langwell->otg.state = OTG_STATE_A_WAIT_VFALL;
+                       }
+               }
+               break;
+       case OTG_STATE_A_HOST:
+               if (langwell->hsm.id) {
+                       langwell->otg.default_a = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.a_bus_drop ||
+               (!langwell->hsm.a_set_b_hnp_en && !langwell->hsm.a_bus_req)) {
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_WAIT_VFALL;
+               } else if (!langwell->hsm.a_vbus_vld) {
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_VBUS_ERR;
+               } else if (langwell->hsm.a_set_b_hnp_en
+                               && !langwell->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(langwell->pdev->irq,
+                               otg_dummy_irq, IRQF_SHARED, driver_name,
+                               langwell->regs) != 0) {
+                               otg_dbg("request interrupt %d failed\n",
+                                               langwell->pdev->irq);
+                       }
+
+                       /* set HABA */
+                       langwell_otg_HABA(1);
+                       langwell->hsm.b_bus_resume = 0;
+                       langwell->hsm.a_aidl_bdis_tmout = 0;
+                       langwell_otg_add_timer(a_aidl_bdis_tmr);
+                       langwell_otg_loc_sof(0);
+                       langwell->otg.state = OTG_STATE_A_SUSPEND;
+               } else if (!langwell->hsm.b_conn || !langwell->hsm.a_bus_req) {
+                       langwell->hsm.a_wait_bcon_tmout = 0;
+                       langwell->hsm.a_set_b_hnp_en = 0;
+                       langwell_otg_add_timer(a_wait_bcon_tmr);
+                       langwell->otg.state = OTG_STATE_A_WAIT_BCON;
+               }
+               break;
+       case OTG_STATE_A_SUSPEND:
+               if (langwell->hsm.id) {
+                       langwell_otg_del_timer(a_aidl_bdis_tmr);
+                       langwell_otg_HABA(0);
+                       free_irq(langwell->pdev->irq, langwell->regs);
+                       langwell->otg.default_a = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.a_bus_req ||
+                               langwell->hsm.b_bus_resume) {
+                       langwell_otg_del_timer(a_aidl_bdis_tmr);
+                       langwell_otg_HABA(0);
+                       free_irq(langwell->pdev->irq, langwell->regs);
+                       langwell->hsm.a_suspend_req = 0;
+                       langwell_otg_loc_sof(1);
+                       langwell->otg.state = OTG_STATE_A_HOST;
+               } else if (langwell->hsm.a_aidl_bdis_tmout ||
+                               langwell->hsm.a_bus_drop) {
+                       langwell_otg_del_timer(a_aidl_bdis_tmr);
+                       langwell_otg_HABA(0);
+                       free_irq(langwell->pdev->irq, langwell->regs);
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_WAIT_VFALL;
+               } else if (!langwell->hsm.b_conn &&
+                               langwell->hsm.a_set_b_hnp_en) {
+                       langwell_otg_del_timer(a_aidl_bdis_tmr);
+                       langwell_otg_HABA(0);
+                       free_irq(langwell->pdev->irq, langwell->regs);
+
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+
+                       langwell->hsm.b_bus_suspend = 0;
+                       langwell->hsm.b_bus_suspend_vld = 0;
+                       langwell->hsm.b_bus_suspend_tmout = 0;
+
+                       /* msleep(200); */
+                       if (langwell->client_ops)
+                               langwell->client_ops->resume(langwell->pdev);
+                       else
+                               otg_dbg("client driver not loaded.\n");
+
+                       langwell_otg_add_timer(b_bus_suspend_tmr);
+                       langwell->otg.state = OTG_STATE_A_PERIPHERAL;
+                       break;
+               } else if (!langwell->hsm.a_vbus_vld) {
+                       langwell_otg_del_timer(a_aidl_bdis_tmr);
+                       langwell_otg_HABA(0);
+                       free_irq(langwell->pdev->irq, langwell->regs);
+                       if (langwell->host_ops)
+                               langwell->host_ops->remove(langwell->pdev);
+                       else
+                               otg_dbg("host driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_VBUS_ERR;
+               }
+               break;
+       case OTG_STATE_A_PERIPHERAL:
+               if (langwell->hsm.id) {
+                       langwell_otg_del_timer(b_bus_suspend_tmr);
+                       langwell->otg.default_a = 0;
+                       langwell->hsm.b_bus_req = 0;
+                       if (langwell->client_ops)
+                               langwell->client_ops->suspend(langwell->pdev,
+                                       PMSG_FREEZE);
+                       else
+                               otg_dbg("client driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (!langwell->hsm.a_vbus_vld) {
+                       langwell_otg_del_timer(b_bus_suspend_tmr);
+                       if (langwell->client_ops)
+                               langwell->client_ops->suspend(langwell->pdev,
+                                       PMSG_FREEZE);
+                       else
+                               otg_dbg("client driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_VBUS_ERR;
+               } else if (langwell->hsm.a_bus_drop) {
+                       langwell_otg_del_timer(b_bus_suspend_tmr);
+                       if (langwell->client_ops)
+                               langwell->client_ops->suspend(langwell->pdev,
+                                       PMSG_FREEZE);
+                       else
+                               otg_dbg("client driver has been removed.\n");
+                       langwell_otg_drv_vbus(0);
+                       langwell->otg.state = OTG_STATE_A_WAIT_VFALL;
+               } else if (langwell->hsm.b_bus_suspend) {
+                       langwell_otg_del_timer(b_bus_suspend_tmr);
+                       if (langwell->client_ops)
+                               langwell->client_ops->suspend(langwell->pdev,
+                                       PMSG_FREEZE);
+                       else
+                               otg_dbg("client driver has been removed.\n");
+
+                       if (langwell->host_ops)
+                               langwell->host_ops->probe(langwell->pdev,
+                                               langwell->host_ops->id_table);
+                       else
+                               otg_dbg("host driver not loaded.\n");
+                       langwell->hsm.a_set_b_hnp_en = 0;
+                       langwell->hsm.a_wait_bcon_tmout = 0;
+                       langwell_otg_add_timer(a_wait_bcon_tmr);
+                       langwell->otg.state = OTG_STATE_A_WAIT_BCON;
+               } else if (langwell->hsm.b_bus_suspend_tmout) {
+                       u32     val;
+                       val = readl(langwell->regs + CI_PORTSC1);
+                       if (!(val & PORTSC_SUSP))
+                               break;
+                       if (langwell->client_ops)
+                               langwell->client_ops->suspend(langwell->pdev,
+                                               PMSG_FREEZE);
+                       else
+                               otg_dbg("client driver has been removed.\n");
+                       if (langwell->host_ops)
+                               langwell->host_ops->probe(langwell->pdev,
+                                               langwell->host_ops->id_table);
+                       else
+                               otg_dbg("host driver not loaded.\n");
+                       langwell->hsm.a_set_b_hnp_en = 0;
+                       langwell->hsm.a_wait_bcon_tmout = 0;
+                       langwell_otg_add_timer(a_wait_bcon_tmr);
+                       langwell->otg.state = OTG_STATE_A_WAIT_BCON;
+               }
+               break;
+       case OTG_STATE_A_VBUS_ERR:
+               if (langwell->hsm.id) {
+                       langwell->otg.default_a = 0;
+                       langwell->hsm.a_clr_err = 0;
+                       langwell->hsm.a_srp_det = 0;
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.a_clr_err) {
+                       langwell->hsm.a_clr_err = 0;
+                       langwell->hsm.a_srp_det = 0;
+                       reset_otg();
+                       init_hsm();
+                       if (langwell->otg.state == OTG_STATE_A_IDLE)
+                               queue_work(langwell->qwork, &langwell->work);
+               }
+               break;
+       case OTG_STATE_A_WAIT_VFALL:
+               if (langwell->hsm.id) {
+                       langwell->otg.default_a = 0;
+                       langwell->otg.state = OTG_STATE_B_IDLE;
+                       queue_work(langwell->qwork, &langwell->work);
+               } else if (langwell->hsm.a_bus_req) {
+                       langwell_otg_drv_vbus(1);
+                       langwell->hsm.a_wait_vrise_tmout = 0;
+                       langwell_otg_add_timer(a_wait_vrise_tmr);
+                       langwell->otg.state = OTG_STATE_A_WAIT_VRISE;
+               } else if (!langwell->hsm.a_sess_vld) {
+                       langwell->hsm.a_srp_det = 0;
+                       langwell_otg_drv_vbus(0);
+                       set_host_mode();
+                       langwell->otg.state = OTG_STATE_A_IDLE;
+               }
+               break;
+       default:
+               ;
+       }
+
+       otg_dbg("%s: new state = %s\n", __func__,
+                       state_string(langwell->otg.state));
+}
+
+       static ssize_t
+show_registers(struct device *_dev, struct device_attribute *attr, char *buf)
+{
+       struct langwell_otg *langwell;
+       char *next;
+       unsigned size;
+       unsigned t;
+
+       langwell = the_transceiver;
+       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(langwell->regs + 0x30),
+               readl(langwell->regs + 0x34),
+               readl(langwell->regs + 0x38),
+               readl(langwell->regs + 0x48),
+               readl(langwell->regs + 0x74),
+               readl(langwell->regs + 0xb4),
+               readl(langwell->regs + 0xf4),
+               readl(langwell->regs + 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 *langwell;
+       char *next;
+       unsigned size;
+       unsigned t;
+
+       langwell = the_transceiver;
+       next = buf;
+       size = PAGE_SIZE;
+
+       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(langwell->otg.state),
+               langwell->hsm.a_bus_resume,
+               langwell->hsm.a_bus_suspend,
+               langwell->hsm.a_conn,
+               langwell->hsm.a_sess_vld,
+               langwell->hsm.a_srp_det,
+               langwell->hsm.a_vbus_vld,
+               langwell->hsm.b_bus_resume,
+               langwell->hsm.b_bus_suspend,
+               langwell->hsm.b_conn,
+               langwell->hsm.b_se0_srp,
+               langwell->hsm.b_sess_end,
+               langwell->hsm.b_sess_vld,
+               langwell->hsm.id,
+               langwell->hsm.a_set_b_hnp_en,
+               langwell->hsm.b_srp_done,
+               langwell->hsm.b_hnp_enable,
+               langwell->hsm.a_wait_vrise_tmout,
+               langwell->hsm.a_wait_bcon_tmout,
+               langwell->hsm.a_aidl_bdis_tmout,
+               langwell->hsm.b_ase0_brst_tmout,
+               langwell->hsm.a_bus_drop,
+               langwell->hsm.a_bus_req,
+               langwell->hsm.a_clr_err,
+               langwell->hsm.a_suspend_req,
+               langwell->hsm.b_bus_req,
+               langwell->hsm.b_bus_suspend_tmout,
+               langwell->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 *langwell;
+       char *next;
+       unsigned size;
+       unsigned t;
+
+       langwell =  the_transceiver;
+       next = buf;
+       size = PAGE_SIZE;
+
+       t = scnprintf(next, size, "%d", langwell->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 *langwell;
+       langwell = the_transceiver;
+       if (!langwell->otg.default_a)
+               return -1;
+       if (count > 2)
+               return -1;
+
+       if (buf[0] == '0') {
+               langwell->hsm.a_bus_req = 0;
+               otg_dbg("a_bus_req = 0\n");
+       } else if (buf[0] == '1') {
+               /* If a_bus_drop is TRUE, a_bus_req can't be set */
+               if (langwell->hsm.a_bus_drop)
+                       return -1;
+               langwell->hsm.a_bus_req = 1;
+               otg_dbg("a_bus_req = 1\n");
+       }
+       if (spin_trylock(&langwell->wq_lock)) {
+               queue_work(langwell->qwork, &langwell->work);
+               spin_unlock(&langwell->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 *langwell;
+       char *next;
+       unsigned size;
+       unsigned t;
+
+       langwell =  the_transceiver;
+       next = buf;
+       size = PAGE_SIZE;
+
+       t = scnprintf(next, size, "%d", langwell->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 *langwell;
+       langwell = the_transceiver;
+       if (!langwell->otg.default_a)
+               return -1;
+       if (count > 2)
+               return -1;
+
+       if (buf[0] == '0') {
+               langwell->hsm.a_bus_drop = 0;
+               otg_dbg("a_bus_drop = 0\n");
+       } else if (buf[0] == '1') {
+               langwell->hsm.a_bus_drop = 1;
+               langwell->hsm.a_bus_req = 0;
+               otg_dbg("a_bus_drop = 1, then a_bus_req = 0\n");
+       }
+       if (spin_trylock(&langwell->wq_lock)) {
+               queue_work(langwell->qwork, &langwell->work);
+               spin_unlock(&langwell->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 *langwell;
+       char *next;
+       unsigned size;
+       unsigned t;
+
+       langwell =  the_transceiver;
+       next = buf;
+       size = PAGE_SIZE;
+
+       t = scnprintf(next, size, "%d", langwell->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 *langwell;
+       langwell = the_transceiver;
+
+       if (langwell->otg.default_a)
+               return -1;
+
+       if (count > 2)
+               return -1;
+
+       if (buf[0] == '0') {
+               langwell->hsm.b_bus_req = 0;
+               otg_dbg("b_bus_req = 0\n");
+       } else if (buf[0] == '1') {
+               langwell->hsm.b_bus_req = 1;
+               otg_dbg("b_bus_req = 1\n");
+       }
+       if (spin_trylock(&langwell->wq_lock)) {
+               queue_work(langwell->qwork, &langwell->work);
+               spin_unlock(&langwell->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 *langwell;
+       langwell = the_transceiver;
+
+       if (!langwell->otg.default_a)
+               return -1;
+       if (count > 2)
+               return -1;
+
+       if (buf[0] == '1') {
+               langwell->hsm.a_clr_err = 1;
+               otg_dbg("a_clr_err = 1\n");
+       }
+       if (spin_trylock(&langwell->wq_lock)) {
+               queue_work(langwell->qwork, &langwell->work);
+               spin_unlock(&langwell->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,
+};
+
+int langwell_register_host(struct pci_driver *host_driver)
+{
+       int     ret = 0;
+
+       the_transceiver->host_ops = host_driver;
+       queue_work(the_transceiver->qwork, &the_transceiver->work);
+       otg_dbg("host controller driver is registered\n");
+
+       return ret;
+}
+EXPORT_SYMBOL(langwell_register_host);
+
+void langwell_unregister_host(struct pci_driver *host_driver)
+{
+       if (the_transceiver->host_ops)
+               the_transceiver->host_ops->remove(the_transceiver->pdev);
+       the_transceiver->host_ops = NULL;
+       the_transceiver->hsm.a_bus_drop = 1;
+       queue_work(the_transceiver->qwork, &the_transceiver->work);
+       otg_dbg("host controller driver is unregistered\n");
+}
+EXPORT_SYMBOL(langwell_unregister_host);
+
+int langwell_register_peripheral(struct pci_driver *client_driver)
+{
+       int     ret = 0;
+
+       if (client_driver)
+               ret = client_driver->probe(the_transceiver->pdev,
+                               client_driver->id_table);
+       if (!ret) {
+               the_transceiver->client_ops = client_driver;
+               queue_work(the_transceiver->qwork, &the_transceiver->work);
+               otg_dbg("client controller driver is registered\n");
+       }
+
+       return ret;
+}
+EXPORT_SYMBOL(langwell_register_peripheral);
+
+void langwell_unregister_peripheral(struct pci_driver *client_driver)
+{
+       if (the_transceiver->client_ops)
+               the_transceiver->client_ops->remove(the_transceiver->pdev);
+       the_transceiver->client_ops = NULL;
+       the_transceiver->hsm.b_bus_req = 0;
+       queue_work(the_transceiver->qwork, &the_transceiver->work);
+       otg_dbg("client controller driver is unregistered\n");
+}
+EXPORT_SYMBOL(langwell_unregister_peripheral);
+
+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     *langwell;
+       char                    qname[] = "langwell_otg_queue";
+
+       retval = 0;
+       otg_dbg("\notg controller is detected.\n");
+       if (pci_enable_device(pdev) < 0) {
+               retval = -ENODEV;
+               goto done;
+       }
+
+       langwell = kzalloc(sizeof *langwell, GFP_KERNEL);
+       if (langwell == NULL) {
+               retval = -ENOMEM;
+               goto done;
+       }
+       the_transceiver = langwell;
+
+       /* 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;
+       }
+       langwell->region = 1;
+
+       base = ioremap_nocache(resource, len);
+       if (base == NULL) {
+               retval = -EFAULT;
+               goto err;
+       }
+       langwell->regs = base;
+
+       if (!pdev->irq) {
+               otg_dbg("No IRQ.\n");
+               retval = -ENODEV;
+               goto err;
+       }
+
+       langwell->qwork = create_workqueue(qname);
+       if (!langwell->qwork) {
+               otg_dbg("cannot create workqueue %s\n", qname);
+               retval = -ENOMEM;
+               goto err;
+       }
+       INIT_WORK(&langwell->work, langwell_otg_work);
+
+       /* OTG common part */
+       langwell->pdev = pdev;
+       langwell->otg.dev = &pdev->dev;
+       langwell->otg.label = driver_name;
+       langwell->otg.set_host = langwell_otg_set_host;
+       langwell->otg.set_peripheral = langwell_otg_set_peripheral;
+       langwell->otg.set_power = langwell_otg_set_power;
+       langwell->otg.start_srp = langwell_otg_start_srp;
+       langwell->otg.state = OTG_STATE_UNDEFINED;
+       if (otg_set_transceiver(&langwell->otg)) {
+               otg_dbg("can't set transceiver\n");
+               retval = -EBUSY;
+               goto err;
+       }
+
+       reset_otg();
+       init_hsm();
+
+       spin_lock_init(&langwell->lock);
+       spin_lock_init(&langwell->wq_lock);
+       INIT_LIST_HEAD(&active_timers);
+       langwell_otg_init_timers(&langwell->hsm);
+
+       if (request_irq(pdev->irq, otg_irq, IRQF_SHARED,
+                               driver_name, langwell) != 0) {
+               otg_dbg("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, langwell->regs + CI_OTGSC);
+
+       retval = device_create_file(&pdev->dev, &dev_attr_registers);
+       if (retval < 0) {
+               otg_dbg("Can't register sysfs attribute: %d\n", retval);
+               goto err;
+       }
+
+       retval = device_create_file(&pdev->dev, &dev_attr_hsm);
+       if (retval < 0) {
+               otg_dbg("Can't hsm sysfs attribute: %d\n", retval);
+               goto err;
+       }
+
+       retval = sysfs_create_group(&pdev->dev.kobj, &debug_dev_attr_group);
+       if (retval < 0) {
+               otg_dbg("Can't register sysfs attr group: %d\n", retval);
+               goto err;
+       }
+
+       if (langwell->otg.state == OTG_STATE_A_IDLE)
+               queue_work(langwell->qwork, &langwell->work);
+
+       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 *langwell;
+
+       langwell = the_transceiver;
+
+       if (langwell->qwork) {
+               flush_workqueue(langwell->qwork);
+               destroy_workqueue(langwell->qwork);
+       }
+       langwell_otg_free_timers();
+
+       /* disable OTGSC interrupt as OTGSC doesn't change in reset */
+       writel(0, langwell->regs + CI_OTGSC);
+
+       if (pdev->irq)
+               free_irq(pdev->irq, langwell);
+       if (langwell->regs)
+               iounmap(langwell->regs);
+       if (langwell->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(langwell);
+       langwell = 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)
+{
+       int     ret = 0;
+       struct langwell_otg *langwell;
+
+       langwell = the_transceiver;
+
+       /* Disbale OTG interrupts */
+       langwell_otg_intr(0);
+
+       if (pdev->irq)
+               free_irq(pdev->irq, langwell);
+
+       /* Prevent more otg_work */
+       flush_workqueue(langwell->qwork);
+       spin_lock(&langwell->wq_lock);
+
+       /* start actions */
+       switch (langwell->otg.state) {
+       case OTG_STATE_A_IDLE:
+       case OTG_STATE_B_IDLE:
+       case OTG_STATE_A_WAIT_VFALL:
+       case OTG_STATE_A_VBUS_ERR:
+               transceiver_suspend(pdev);
+               break;
+       case OTG_STATE_A_WAIT_VRISE:
+               langwell_otg_del_timer(a_wait_vrise_tmr);
+               langwell->hsm.a_srp_det = 0;
+               langwell_otg_drv_vbus(0);
+               langwell->otg.state = OTG_STATE_A_IDLE;
+               transceiver_suspend(pdev);
+               break;
+       case OTG_STATE_A_WAIT_BCON:
+               langwell_otg_del_timer(a_wait_bcon_tmr);
+               if (langwell->host_ops)
+                       ret = langwell->host_ops->suspend(pdev, message);
+               langwell_otg_drv_vbus(0);
+               break;
+       case OTG_STATE_A_HOST:
+               if (langwell->host_ops)
+                       ret = langwell->host_ops->suspend(pdev, message);
+               langwell_otg_drv_vbus(0);
+               langwell_otg_phy_low_power(1);
+               break;
+       case OTG_STATE_A_SUSPEND:
+               langwell_otg_del_timer(a_aidl_bdis_tmr);
+               langwell_otg_HABA(0);
+               if (langwell->host_ops)
+                       langwell->host_ops->remove(pdev);
+               else
+                       otg_dbg("host driver has been removed.\n");
+               langwell_otg_drv_vbus(0);
+               transceiver_suspend(pdev);
+               langwell->otg.state = OTG_STATE_A_WAIT_VFALL;
+               break;
+       case OTG_STATE_A_PERIPHERAL:
+               if (langwell->client_ops)
+                       ret = langwell->client_ops->suspend(pdev, message);
+               else
+                       otg_dbg("client driver has been removed.\n");
+               langwell_otg_drv_vbus(0);
+               transceiver_suspend(pdev);
+               langwell->otg.state = OTG_STATE_A_WAIT_VFALL;
+               break;
+       case OTG_STATE_B_HOST:
+               if (langwell->host_ops)
+                       langwell->host_ops->remove(pdev);
+               else
+                       otg_dbg("host driver has been removed.\n");
+               langwell->hsm.b_bus_req = 0;
+               transceiver_suspend(pdev);
+               langwell->otg.state = OTG_STATE_B_IDLE;
+               break;
+       case OTG_STATE_B_PERIPHERAL:
+               if (langwell->client_ops)
+                       ret = langwell->client_ops->suspend(pdev, message);
+               else
+                       otg_dbg("client driver has been removed.\n");
+               break;
+       case OTG_STATE_B_WAIT_ACON:
+               langwell_otg_del_timer(b_ase0_brst_tmr);
+               langwell_otg_HAAR(0);
+               if (langwell->host_ops)
+                       langwell->host_ops->remove(pdev);
+               else
+                       otg_dbg("host driver has been removed.\n");
+               langwell->hsm.b_bus_req = 0;
+               langwell->otg.state = OTG_STATE_B_IDLE;
+               transceiver_suspend(pdev);
+               break;
+       default:
+               otg_dbg("error state before suspend\n ");
+               break;
+       }
+       spin_unlock(&langwell->wq_lock);
+
+       return ret;
+}
+
+static void transceiver_resume(struct pci_dev *pdev)
+{
+       pci_restore_state(pdev);
+       pci_set_power_state(pdev, PCI_D0);
+       langwell_otg_phy_low_power(0);
+}
+
+static int langwell_otg_resume(struct pci_dev *pdev)
+{
+       int     ret = 0;
+       struct langwell_otg *langwell;
+
+       langwell = the_transceiver;
+
+       spin_lock(&langwell->wq_lock);
+
+       switch (langwell->otg.state) {
+       case OTG_STATE_A_IDLE:
+       case OTG_STATE_B_IDLE:
+       case OTG_STATE_A_WAIT_VFALL:
+       case OTG_STATE_A_VBUS_ERR:
+               transceiver_resume(pdev);
+               break;
+       case OTG_STATE_A_WAIT_BCON:
+               langwell_otg_add_timer(a_wait_bcon_tmr);
+               langwell_otg_drv_vbus(1);
+               if (langwell->host_ops)
+                       ret = langwell->host_ops->resume(pdev);
+               break;
+       case OTG_STATE_A_HOST:
+               langwell_otg_drv_vbus(1);
+               langwell_otg_phy_low_power(0);
+               if (langwell->host_ops)
+                       ret = langwell->host_ops->resume(pdev);
+               break;
+       case OTG_STATE_B_PERIPHERAL:
+               if (langwell->client_ops)
+                       ret = langwell->client_ops->resume(pdev);
+               else
+                       otg_dbg("client driver not loaded.\n");
+               break;
+       default:
+               otg_dbg("error state before suspend\n ");
+               break;
+       }
+
+       if (request_irq(pdev->irq, otg_irq, IRQF_SHARED,
+                               driver_name, the_transceiver) != 0) {
+               otg_dbg("request interrupt %d failed\n", pdev->irq);
+               ret = -EBUSY;
+       }
+
+       /* enable OTG interrupts */
+       langwell_otg_intr(1);
+
+       spin_unlock(&langwell->wq_lock);
+
+       queue_work(langwell->qwork, &langwell->work);
+
+
+       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);