]> git.karo-electronics.de Git - mv-sheeva.git/blobdiff - drivers/usb/otg/msm72k_otg.c
Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[mv-sheeva.git] / drivers / usb / otg / msm72k_otg.c
diff --git a/drivers/usb/otg/msm72k_otg.c b/drivers/usb/otg/msm72k_otg.c
new file mode 100644 (file)
index 0000000..1cd52ed
--- /dev/null
@@ -0,0 +1,1125 @@
+/* Copyright (c) 2009-2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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 Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/uaccess.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/usb.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/ulpi.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/hcd.h>
+#include <linux/usb/msm_hsusb.h>
+#include <linux/usb/msm_hsusb_hw.h>
+
+#include <mach/clk.h>
+
+#define MSM_USB_BASE   (motg->regs)
+#define DRIVER_NAME    "msm_otg"
+
+#define ULPI_IO_TIMEOUT_USEC   (10 * 1000)
+static int ulpi_read(struct otg_transceiver *otg, u32 reg)
+{
+       struct msm_otg *motg = container_of(otg, struct msm_otg, otg);
+       int cnt = 0;
+
+       /* initiate read operation */
+       writel(ULPI_RUN | ULPI_READ | ULPI_ADDR(reg),
+              USB_ULPI_VIEWPORT);
+
+       /* wait for completion */
+       while (cnt < ULPI_IO_TIMEOUT_USEC) {
+               if (!(readl(USB_ULPI_VIEWPORT) & ULPI_RUN))
+                       break;
+               udelay(1);
+               cnt++;
+       }
+
+       if (cnt >= ULPI_IO_TIMEOUT_USEC) {
+               dev_err(otg->dev, "ulpi_read: timeout %08x\n",
+                       readl(USB_ULPI_VIEWPORT));
+               return -ETIMEDOUT;
+       }
+       return ULPI_DATA_READ(readl(USB_ULPI_VIEWPORT));
+}
+
+static int ulpi_write(struct otg_transceiver *otg, u32 val, u32 reg)
+{
+       struct msm_otg *motg = container_of(otg, struct msm_otg, otg);
+       int cnt = 0;
+
+       /* initiate write operation */
+       writel(ULPI_RUN | ULPI_WRITE |
+              ULPI_ADDR(reg) | ULPI_DATA(val),
+              USB_ULPI_VIEWPORT);
+
+       /* wait for completion */
+       while (cnt < ULPI_IO_TIMEOUT_USEC) {
+               if (!(readl(USB_ULPI_VIEWPORT) & ULPI_RUN))
+                       break;
+               udelay(1);
+               cnt++;
+       }
+
+       if (cnt >= ULPI_IO_TIMEOUT_USEC) {
+               dev_err(otg->dev, "ulpi_write: timeout\n");
+               return -ETIMEDOUT;
+       }
+       return 0;
+}
+
+static struct otg_io_access_ops msm_otg_io_ops = {
+       .read = ulpi_read,
+       .write = ulpi_write,
+};
+
+static void ulpi_init(struct msm_otg *motg)
+{
+       struct msm_otg_platform_data *pdata = motg->pdata;
+       int *seq = pdata->phy_init_seq;
+
+       if (!seq)
+               return;
+
+       while (seq[0] >= 0) {
+               dev_vdbg(motg->otg.dev, "ulpi: write 0x%02x to 0x%02x\n",
+                               seq[0], seq[1]);
+               ulpi_write(&motg->otg, seq[0], seq[1]);
+               seq += 2;
+       }
+}
+
+static int msm_otg_link_clk_reset(struct msm_otg *motg, bool assert)
+{
+       int ret;
+
+       if (assert) {
+               ret = clk_reset(motg->clk, CLK_RESET_ASSERT);
+               if (ret)
+                       dev_err(motg->otg.dev, "usb hs_clk assert failed\n");
+       } else {
+               ret = clk_reset(motg->clk, CLK_RESET_DEASSERT);
+               if (ret)
+                       dev_err(motg->otg.dev, "usb hs_clk deassert failed\n");
+       }
+       return ret;
+}
+
+static int msm_otg_phy_clk_reset(struct msm_otg *motg)
+{
+       int ret;
+
+       ret = clk_reset(motg->phy_reset_clk, CLK_RESET_ASSERT);
+       if (ret) {
+               dev_err(motg->otg.dev, "usb phy clk assert failed\n");
+               return ret;
+       }
+       usleep_range(10000, 12000);
+       ret = clk_reset(motg->phy_reset_clk, CLK_RESET_DEASSERT);
+       if (ret)
+               dev_err(motg->otg.dev, "usb phy clk deassert failed\n");
+       return ret;
+}
+
+static int msm_otg_phy_reset(struct msm_otg *motg)
+{
+       u32 val;
+       int ret;
+       int retries;
+
+       ret = msm_otg_link_clk_reset(motg, 1);
+       if (ret)
+               return ret;
+       ret = msm_otg_phy_clk_reset(motg);
+       if (ret)
+               return ret;
+       ret = msm_otg_link_clk_reset(motg, 0);
+       if (ret)
+               return ret;
+
+       val = readl(USB_PORTSC) & ~PORTSC_PTS_MASK;
+       writel(val | PORTSC_PTS_ULPI, USB_PORTSC);
+
+       for (retries = 3; retries > 0; retries--) {
+               ret = ulpi_write(&motg->otg, ULPI_FUNC_CTRL_SUSPENDM,
+                               ULPI_CLR(ULPI_FUNC_CTRL));
+               if (!ret)
+                       break;
+               ret = msm_otg_phy_clk_reset(motg);
+               if (ret)
+                       return ret;
+       }
+       if (!retries)
+               return -ETIMEDOUT;
+
+       /* This reset calibrates the phy, if the above write succeeded */
+       ret = msm_otg_phy_clk_reset(motg);
+       if (ret)
+               return ret;
+
+       for (retries = 3; retries > 0; retries--) {
+               ret = ulpi_read(&motg->otg, ULPI_DEBUG);
+               if (ret != -ETIMEDOUT)
+                       break;
+               ret = msm_otg_phy_clk_reset(motg);
+               if (ret)
+                       return ret;
+       }
+       if (!retries)
+               return -ETIMEDOUT;
+
+       dev_info(motg->otg.dev, "phy_reset: success\n");
+       return 0;
+}
+
+#define LINK_RESET_TIMEOUT_USEC                (250 * 1000)
+static int msm_otg_reset(struct otg_transceiver *otg)
+{
+       struct msm_otg *motg = container_of(otg, struct msm_otg, otg);
+       struct msm_otg_platform_data *pdata = motg->pdata;
+       int cnt = 0;
+       int ret;
+       u32 val = 0;
+       u32 ulpi_val = 0;
+
+       ret = msm_otg_phy_reset(motg);
+       if (ret) {
+               dev_err(otg->dev, "phy_reset failed\n");
+               return ret;
+       }
+
+       ulpi_init(motg);
+
+       writel(USBCMD_RESET, USB_USBCMD);
+       while (cnt < LINK_RESET_TIMEOUT_USEC) {
+               if (!(readl(USB_USBCMD) & USBCMD_RESET))
+                       break;
+               udelay(1);
+               cnt++;
+       }
+       if (cnt >= LINK_RESET_TIMEOUT_USEC)
+               return -ETIMEDOUT;
+
+       /* select ULPI phy */
+       writel(0x80000000, USB_PORTSC);
+
+       msleep(100);
+
+       writel(0x0, USB_AHBBURST);
+       writel(0x00, USB_AHBMODE);
+
+       if (pdata->otg_control == OTG_PHY_CONTROL) {
+               val = readl(USB_OTGSC);
+               if (pdata->mode == USB_OTG) {
+                       ulpi_val = ULPI_INT_IDGRD | ULPI_INT_SESS_VALID;
+                       val |= OTGSC_IDIE | OTGSC_BSVIE;
+               } else if (pdata->mode == USB_PERIPHERAL) {
+                       ulpi_val = ULPI_INT_SESS_VALID;
+                       val |= OTGSC_BSVIE;
+               }
+               writel(val, USB_OTGSC);
+               ulpi_write(otg, ulpi_val, ULPI_USB_INT_EN_RISE);
+               ulpi_write(otg, ulpi_val, ULPI_USB_INT_EN_FALL);
+       }
+
+       return 0;
+}
+
+#define PHY_SUSPEND_TIMEOUT_USEC       (500 * 1000)
+static int msm_otg_suspend(struct msm_otg *motg)
+{
+       struct otg_transceiver *otg = &motg->otg;
+       struct usb_bus *bus = otg->host;
+       struct msm_otg_platform_data *pdata = motg->pdata;
+       int cnt = 0;
+
+       if (atomic_read(&motg->in_lpm))
+               return 0;
+
+       disable_irq(motg->irq);
+       /*
+        * Interrupt Latch Register auto-clear feature is not present
+        * in all PHY versions. Latch register is clear on read type.
+        * Clear latch register to avoid spurious wakeup from
+        * low power mode (LPM).
+        */
+       ulpi_read(otg, 0x14);
+
+       /*
+        * PHY comparators are disabled when PHY enters into low power
+        * mode (LPM). Keep PHY comparators ON in LPM only when we expect
+        * VBUS/Id notifications from USB PHY. Otherwise turn off USB
+        * PHY comparators. This save significant amount of power.
+        */
+       if (pdata->otg_control == OTG_PHY_CONTROL)
+               ulpi_write(otg, 0x01, 0x30);
+
+       /*
+        * PLL is not turned off when PHY enters into low power mode (LPM).
+        * Disable PLL for maximum power savings.
+        */
+       ulpi_write(otg, 0x08, 0x09);
+
+       /*
+        * PHY may take some time or even fail to enter into low power
+        * mode (LPM). Hence poll for 500 msec and reset the PHY and link
+        * in failure case.
+        */
+       writel(readl(USB_PORTSC) | PORTSC_PHCD, USB_PORTSC);
+       while (cnt < PHY_SUSPEND_TIMEOUT_USEC) {
+               if (readl(USB_PORTSC) & PORTSC_PHCD)
+                       break;
+               udelay(1);
+               cnt++;
+       }
+
+       if (cnt >= PHY_SUSPEND_TIMEOUT_USEC) {
+               dev_err(otg->dev, "Unable to suspend PHY\n");
+               msm_otg_reset(otg);
+               enable_irq(motg->irq);
+               return -ETIMEDOUT;
+       }
+
+       /*
+        * PHY has capability to generate interrupt asynchronously in low
+        * power mode (LPM). This interrupt is level triggered. So USB IRQ
+        * line must be disabled till async interrupt enable bit is cleared
+        * in USBCMD register. Assert STP (ULPI interface STOP signal) to
+        * block data communication from PHY.
+        */
+       writel(readl(USB_USBCMD) | ASYNC_INTR_CTRL | ULPI_STP_CTRL, USB_USBCMD);
+
+       clk_disable(motg->pclk);
+       clk_disable(motg->clk);
+       if (motg->core_clk)
+               clk_disable(motg->core_clk);
+
+       if (device_may_wakeup(otg->dev))
+               enable_irq_wake(motg->irq);
+       if (bus)
+               clear_bit(HCD_FLAG_HW_ACCESSIBLE, &(bus_to_hcd(bus))->flags);
+
+       atomic_set(&motg->in_lpm, 1);
+       enable_irq(motg->irq);
+
+       dev_info(otg->dev, "USB in low power mode\n");
+
+       return 0;
+}
+
+#define PHY_RESUME_TIMEOUT_USEC        (100 * 1000)
+static int msm_otg_resume(struct msm_otg *motg)
+{
+       struct otg_transceiver *otg = &motg->otg;
+       struct usb_bus *bus = otg->host;
+       int cnt = 0;
+       unsigned temp;
+
+       if (!atomic_read(&motg->in_lpm))
+               return 0;
+
+       clk_enable(motg->pclk);
+       clk_enable(motg->clk);
+       if (motg->core_clk)
+               clk_enable(motg->core_clk);
+
+       temp = readl(USB_USBCMD);
+       temp &= ~ASYNC_INTR_CTRL;
+       temp &= ~ULPI_STP_CTRL;
+       writel(temp, USB_USBCMD);
+
+       /*
+        * PHY comes out of low power mode (LPM) in case of wakeup
+        * from asynchronous interrupt.
+        */
+       if (!(readl(USB_PORTSC) & PORTSC_PHCD))
+               goto skip_phy_resume;
+
+       writel(readl(USB_PORTSC) & ~PORTSC_PHCD, USB_PORTSC);
+       while (cnt < PHY_RESUME_TIMEOUT_USEC) {
+               if (!(readl(USB_PORTSC) & PORTSC_PHCD))
+                       break;
+               udelay(1);
+               cnt++;
+       }
+
+       if (cnt >= PHY_RESUME_TIMEOUT_USEC) {
+               /*
+                * This is a fatal error. Reset the link and
+                * PHY. USB state can not be restored. Re-insertion
+                * of USB cable is the only way to get USB working.
+                */
+               dev_err(otg->dev, "Unable to resume USB."
+                               "Re-plugin the cable\n");
+               msm_otg_reset(otg);
+       }
+
+skip_phy_resume:
+       if (device_may_wakeup(otg->dev))
+               disable_irq_wake(motg->irq);
+       if (bus)
+               set_bit(HCD_FLAG_HW_ACCESSIBLE, &(bus_to_hcd(bus))->flags);
+
+       if (motg->async_int) {
+               motg->async_int = 0;
+               pm_runtime_put(otg->dev);
+               enable_irq(motg->irq);
+       }
+
+       atomic_set(&motg->in_lpm, 0);
+
+       dev_info(otg->dev, "USB exited from low power mode\n");
+
+       return 0;
+}
+
+static void msm_otg_start_host(struct otg_transceiver *otg, int on)
+{
+       struct msm_otg *motg = container_of(otg, struct msm_otg, otg);
+       struct msm_otg_platform_data *pdata = motg->pdata;
+       struct usb_hcd *hcd;
+
+       if (!otg->host)
+               return;
+
+       hcd = bus_to_hcd(otg->host);
+
+       if (on) {
+               dev_dbg(otg->dev, "host on\n");
+
+               if (pdata->vbus_power)
+                       pdata->vbus_power(1);
+               /*
+                * Some boards have a switch cotrolled by gpio
+                * to enable/disable internal HUB. Enable internal
+                * HUB before kicking the host.
+                */
+               if (pdata->setup_gpio)
+                       pdata->setup_gpio(OTG_STATE_A_HOST);
+#ifdef CONFIG_USB
+               usb_add_hcd(hcd, hcd->irq, IRQF_SHARED);
+#endif
+       } else {
+               dev_dbg(otg->dev, "host off\n");
+
+#ifdef CONFIG_USB
+               usb_remove_hcd(hcd);
+#endif
+               if (pdata->setup_gpio)
+                       pdata->setup_gpio(OTG_STATE_UNDEFINED);
+               if (pdata->vbus_power)
+                       pdata->vbus_power(0);
+       }
+}
+
+static int msm_otg_set_host(struct otg_transceiver *otg, struct usb_bus *host)
+{
+       struct msm_otg *motg = container_of(otg, struct msm_otg, otg);
+       struct usb_hcd *hcd;
+
+       /*
+        * Fail host registration if this board can support
+        * only peripheral configuration.
+        */
+       if (motg->pdata->mode == USB_PERIPHERAL) {
+               dev_info(otg->dev, "Host mode is not supported\n");
+               return -ENODEV;
+       }
+
+       if (!host) {
+               if (otg->state == OTG_STATE_A_HOST) {
+                       pm_runtime_get_sync(otg->dev);
+                       msm_otg_start_host(otg, 0);
+                       otg->host = NULL;
+                       otg->state = OTG_STATE_UNDEFINED;
+                       schedule_work(&motg->sm_work);
+               } else {
+                       otg->host = NULL;
+               }
+
+               return 0;
+       }
+
+       hcd = bus_to_hcd(host);
+       hcd->power_budget = motg->pdata->power_budget;
+
+       otg->host = host;
+       dev_dbg(otg->dev, "host driver registered w/ tranceiver\n");
+
+       /*
+        * Kick the state machine work, if peripheral is not supported
+        * or peripheral is already registered with us.
+        */
+       if (motg->pdata->mode == USB_HOST || otg->gadget) {
+               pm_runtime_get_sync(otg->dev);
+               schedule_work(&motg->sm_work);
+       }
+
+       return 0;
+}
+
+static void msm_otg_start_peripheral(struct otg_transceiver *otg, int on)
+{
+       struct msm_otg *motg = container_of(otg, struct msm_otg, otg);
+       struct msm_otg_platform_data *pdata = motg->pdata;
+
+       if (!otg->gadget)
+               return;
+
+       if (on) {
+               dev_dbg(otg->dev, "gadget on\n");
+               /*
+                * Some boards have a switch cotrolled by gpio
+                * to enable/disable internal HUB. Disable internal
+                * HUB before kicking the gadget.
+                */
+               if (pdata->setup_gpio)
+                       pdata->setup_gpio(OTG_STATE_B_PERIPHERAL);
+               usb_gadget_vbus_connect(otg->gadget);
+       } else {
+               dev_dbg(otg->dev, "gadget off\n");
+               usb_gadget_vbus_disconnect(otg->gadget);
+               if (pdata->setup_gpio)
+                       pdata->setup_gpio(OTG_STATE_UNDEFINED);
+       }
+
+}
+
+static int msm_otg_set_peripheral(struct otg_transceiver *otg,
+                       struct usb_gadget *gadget)
+{
+       struct msm_otg *motg = container_of(otg, struct msm_otg, otg);
+
+       /*
+        * Fail peripheral registration if this board can support
+        * only host configuration.
+        */
+       if (motg->pdata->mode == USB_HOST) {
+               dev_info(otg->dev, "Peripheral mode is not supported\n");
+               return -ENODEV;
+       }
+
+       if (!gadget) {
+               if (otg->state == OTG_STATE_B_PERIPHERAL) {
+                       pm_runtime_get_sync(otg->dev);
+                       msm_otg_start_peripheral(otg, 0);
+                       otg->gadget = NULL;
+                       otg->state = OTG_STATE_UNDEFINED;
+                       schedule_work(&motg->sm_work);
+               } else {
+                       otg->gadget = NULL;
+               }
+
+               return 0;
+       }
+       otg->gadget = gadget;
+       dev_dbg(otg->dev, "peripheral driver registered w/ tranceiver\n");
+
+       /*
+        * Kick the state machine work, if host is not supported
+        * or host is already registered with us.
+        */
+       if (motg->pdata->mode == USB_PERIPHERAL || otg->host) {
+               pm_runtime_get_sync(otg->dev);
+               schedule_work(&motg->sm_work);
+       }
+
+       return 0;
+}
+
+/*
+ * We support OTG, Peripheral only and Host only configurations. In case
+ * of OTG, mode switch (host-->peripheral/peripheral-->host) can happen
+ * via Id pin status or user request (debugfs). Id/BSV interrupts are not
+ * enabled when switch is controlled by user and default mode is supplied
+ * by board file, which can be changed by userspace later.
+ */
+static void msm_otg_init_sm(struct msm_otg *motg)
+{
+       struct msm_otg_platform_data *pdata = motg->pdata;
+       u32 otgsc = readl(USB_OTGSC);
+
+       switch (pdata->mode) {
+       case USB_OTG:
+               if (pdata->otg_control == OTG_PHY_CONTROL) {
+                       if (otgsc & OTGSC_ID)
+                               set_bit(ID, &motg->inputs);
+                       else
+                               clear_bit(ID, &motg->inputs);
+
+                       if (otgsc & OTGSC_BSV)
+                               set_bit(B_SESS_VLD, &motg->inputs);
+                       else
+                               clear_bit(B_SESS_VLD, &motg->inputs);
+               } else if (pdata->otg_control == OTG_USER_CONTROL) {
+                       if (pdata->default_mode == USB_HOST) {
+                               clear_bit(ID, &motg->inputs);
+                       } else if (pdata->default_mode == USB_PERIPHERAL) {
+                               set_bit(ID, &motg->inputs);
+                               set_bit(B_SESS_VLD, &motg->inputs);
+                       } else {
+                               set_bit(ID, &motg->inputs);
+                               clear_bit(B_SESS_VLD, &motg->inputs);
+                       }
+               }
+               break;
+       case USB_HOST:
+               clear_bit(ID, &motg->inputs);
+               break;
+       case USB_PERIPHERAL:
+               set_bit(ID, &motg->inputs);
+               if (otgsc & OTGSC_BSV)
+                       set_bit(B_SESS_VLD, &motg->inputs);
+               else
+                       clear_bit(B_SESS_VLD, &motg->inputs);
+               break;
+       default:
+               break;
+       }
+}
+
+static void msm_otg_sm_work(struct work_struct *w)
+{
+       struct msm_otg *motg = container_of(w, struct msm_otg, sm_work);
+       struct otg_transceiver *otg = &motg->otg;
+
+       switch (otg->state) {
+       case OTG_STATE_UNDEFINED:
+               dev_dbg(otg->dev, "OTG_STATE_UNDEFINED state\n");
+               msm_otg_reset(otg);
+               msm_otg_init_sm(motg);
+               otg->state = OTG_STATE_B_IDLE;
+               /* FALL THROUGH */
+       case OTG_STATE_B_IDLE:
+               dev_dbg(otg->dev, "OTG_STATE_B_IDLE state\n");
+               if (!test_bit(ID, &motg->inputs) && otg->host) {
+                       /* disable BSV bit */
+                       writel(readl(USB_OTGSC) & ~OTGSC_BSVIE, USB_OTGSC);
+                       msm_otg_start_host(otg, 1);
+                       otg->state = OTG_STATE_A_HOST;
+               } else if (test_bit(B_SESS_VLD, &motg->inputs) && otg->gadget) {
+                       msm_otg_start_peripheral(otg, 1);
+                       otg->state = OTG_STATE_B_PERIPHERAL;
+               }
+               pm_runtime_put_sync(otg->dev);
+               break;
+       case OTG_STATE_B_PERIPHERAL:
+               dev_dbg(otg->dev, "OTG_STATE_B_PERIPHERAL state\n");
+               if (!test_bit(B_SESS_VLD, &motg->inputs) ||
+                               !test_bit(ID, &motg->inputs)) {
+                       msm_otg_start_peripheral(otg, 0);
+                       otg->state = OTG_STATE_B_IDLE;
+                       msm_otg_reset(otg);
+                       schedule_work(w);
+               }
+               break;
+       case OTG_STATE_A_HOST:
+               dev_dbg(otg->dev, "OTG_STATE_A_HOST state\n");
+               if (test_bit(ID, &motg->inputs)) {
+                       msm_otg_start_host(otg, 0);
+                       otg->state = OTG_STATE_B_IDLE;
+                       msm_otg_reset(otg);
+                       schedule_work(w);
+               }
+               break;
+       default:
+               break;
+       }
+}
+
+static irqreturn_t msm_otg_irq(int irq, void *data)
+{
+       struct msm_otg *motg = data;
+       struct otg_transceiver *otg = &motg->otg;
+       u32 otgsc = 0;
+
+       if (atomic_read(&motg->in_lpm)) {
+               disable_irq_nosync(irq);
+               motg->async_int = 1;
+               pm_runtime_get(otg->dev);
+               return IRQ_HANDLED;
+       }
+
+       otgsc = readl(USB_OTGSC);
+       if (!(otgsc & (OTGSC_IDIS | OTGSC_BSVIS)))
+               return IRQ_NONE;
+
+       if ((otgsc & OTGSC_IDIS) && (otgsc & OTGSC_IDIE)) {
+               if (otgsc & OTGSC_ID)
+                       set_bit(ID, &motg->inputs);
+               else
+                       clear_bit(ID, &motg->inputs);
+               dev_dbg(otg->dev, "ID set/clear\n");
+               pm_runtime_get_noresume(otg->dev);
+       } else if ((otgsc & OTGSC_BSVIS) && (otgsc & OTGSC_BSVIE)) {
+               if (otgsc & OTGSC_BSV)
+                       set_bit(B_SESS_VLD, &motg->inputs);
+               else
+                       clear_bit(B_SESS_VLD, &motg->inputs);
+               dev_dbg(otg->dev, "BSV set/clear\n");
+               pm_runtime_get_noresume(otg->dev);
+       }
+
+       writel(otgsc, USB_OTGSC);
+       schedule_work(&motg->sm_work);
+       return IRQ_HANDLED;
+}
+
+static int msm_otg_mode_show(struct seq_file *s, void *unused)
+{
+       struct msm_otg *motg = s->private;
+       struct otg_transceiver *otg = &motg->otg;
+
+       switch (otg->state) {
+       case OTG_STATE_A_HOST:
+               seq_printf(s, "host\n");
+               break;
+       case OTG_STATE_B_PERIPHERAL:
+               seq_printf(s, "peripheral\n");
+               break;
+       default:
+               seq_printf(s, "none\n");
+               break;
+       }
+
+       return 0;
+}
+
+static int msm_otg_mode_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, msm_otg_mode_show, inode->i_private);
+}
+
+static ssize_t msm_otg_mode_write(struct file *file, const char __user *ubuf,
+                               size_t count, loff_t *ppos)
+{
+       struct msm_otg *motg = file->private_data;
+       char buf[16];
+       struct otg_transceiver *otg = &motg->otg;
+       int status = count;
+       enum usb_mode_type req_mode;
+
+       memset(buf, 0x00, sizeof(buf));
+
+       if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count))) {
+               status = -EFAULT;
+               goto out;
+       }
+
+       if (!strncmp(buf, "host", 4)) {
+               req_mode = USB_HOST;
+       } else if (!strncmp(buf, "peripheral", 10)) {
+               req_mode = USB_PERIPHERAL;
+       } else if (!strncmp(buf, "none", 4)) {
+               req_mode = USB_NONE;
+       } else {
+               status = -EINVAL;
+               goto out;
+       }
+
+       switch (req_mode) {
+       case USB_NONE:
+               switch (otg->state) {
+               case OTG_STATE_A_HOST:
+               case OTG_STATE_B_PERIPHERAL:
+                       set_bit(ID, &motg->inputs);
+                       clear_bit(B_SESS_VLD, &motg->inputs);
+                       break;
+               default:
+                       goto out;
+               }
+               break;
+       case USB_PERIPHERAL:
+               switch (otg->state) {
+               case OTG_STATE_B_IDLE:
+               case OTG_STATE_A_HOST:
+                       set_bit(ID, &motg->inputs);
+                       set_bit(B_SESS_VLD, &motg->inputs);
+                       break;
+               default:
+                       goto out;
+               }
+               break;
+       case USB_HOST:
+               switch (otg->state) {
+               case OTG_STATE_B_IDLE:
+               case OTG_STATE_B_PERIPHERAL:
+                       clear_bit(ID, &motg->inputs);
+                       break;
+               default:
+                       goto out;
+               }
+               break;
+       default:
+               goto out;
+       }
+
+       pm_runtime_get_sync(otg->dev);
+       schedule_work(&motg->sm_work);
+out:
+       return status;
+}
+
+const struct file_operations msm_otg_mode_fops = {
+       .open = msm_otg_mode_open,
+       .read = seq_read,
+       .write = msm_otg_mode_write,
+       .llseek = seq_lseek,
+       .release = single_release,
+};
+
+static struct dentry *msm_otg_dbg_root;
+static struct dentry *msm_otg_dbg_mode;
+
+static int msm_otg_debugfs_init(struct msm_otg *motg)
+{
+       msm_otg_dbg_root = debugfs_create_dir("msm_otg", NULL);
+
+       if (!msm_otg_dbg_root || IS_ERR(msm_otg_dbg_root))
+               return -ENODEV;
+
+       msm_otg_dbg_mode = debugfs_create_file("mode", S_IRUGO | S_IWUSR,
+                               msm_otg_dbg_root, motg, &msm_otg_mode_fops);
+       if (!msm_otg_dbg_mode) {
+               debugfs_remove(msm_otg_dbg_root);
+               msm_otg_dbg_root = NULL;
+               return -ENODEV;
+       }
+
+       return 0;
+}
+
+static void msm_otg_debugfs_cleanup(void)
+{
+       debugfs_remove(msm_otg_dbg_mode);
+       debugfs_remove(msm_otg_dbg_root);
+}
+
+static int __init msm_otg_probe(struct platform_device *pdev)
+{
+       int ret = 0;
+       struct resource *res;
+       struct msm_otg *motg;
+       struct otg_transceiver *otg;
+
+       dev_info(&pdev->dev, "msm_otg probe\n");
+       if (!pdev->dev.platform_data) {
+               dev_err(&pdev->dev, "No platform data given. Bailing out\n");
+               return -ENODEV;
+       }
+
+       motg = kzalloc(sizeof(struct msm_otg), GFP_KERNEL);
+       if (!motg) {
+               dev_err(&pdev->dev, "unable to allocate msm_otg\n");
+               return -ENOMEM;
+       }
+
+       motg->pdata = pdev->dev.platform_data;
+       otg = &motg->otg;
+       otg->dev = &pdev->dev;
+
+       motg->phy_reset_clk = clk_get(&pdev->dev, "usb_phy_clk");
+       if (IS_ERR(motg->phy_reset_clk)) {
+               dev_err(&pdev->dev, "failed to get usb_phy_clk\n");
+               ret = PTR_ERR(motg->phy_reset_clk);
+               goto free_motg;
+       }
+
+       motg->clk = clk_get(&pdev->dev, "usb_hs_clk");
+       if (IS_ERR(motg->clk)) {
+               dev_err(&pdev->dev, "failed to get usb_hs_clk\n");
+               ret = PTR_ERR(motg->clk);
+               goto put_phy_reset_clk;
+       }
+
+       motg->pclk = clk_get(&pdev->dev, "usb_hs_pclk");
+       if (IS_ERR(motg->pclk)) {
+               dev_err(&pdev->dev, "failed to get usb_hs_pclk\n");
+               ret = PTR_ERR(motg->pclk);
+               goto put_clk;
+       }
+
+       /*
+        * USB core clock is not present on all MSM chips. This
+        * clock is introduced to remove the dependency on AXI
+        * bus frequency.
+        */
+       motg->core_clk = clk_get(&pdev->dev, "usb_hs_core_clk");
+       if (IS_ERR(motg->core_clk))
+               motg->core_clk = NULL;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!res) {
+               dev_err(&pdev->dev, "failed to get platform resource mem\n");
+               ret = -ENODEV;
+               goto put_core_clk;
+       }
+
+       motg->regs = ioremap(res->start, resource_size(res));
+       if (!motg->regs) {
+               dev_err(&pdev->dev, "ioremap failed\n");
+               ret = -ENOMEM;
+               goto put_core_clk;
+       }
+       dev_info(&pdev->dev, "OTG regs = %p\n", motg->regs);
+
+       motg->irq = platform_get_irq(pdev, 0);
+       if (!motg->irq) {
+               dev_err(&pdev->dev, "platform_get_irq failed\n");
+               ret = -ENODEV;
+               goto free_regs;
+       }
+
+       clk_enable(motg->clk);
+       clk_enable(motg->pclk);
+       if (motg->core_clk)
+               clk_enable(motg->core_clk);
+
+       writel(0, USB_USBINTR);
+       writel(0, USB_OTGSC);
+
+       INIT_WORK(&motg->sm_work, msm_otg_sm_work);
+       ret = request_irq(motg->irq, msm_otg_irq, IRQF_SHARED,
+                                       "msm_otg", motg);
+       if (ret) {
+               dev_err(&pdev->dev, "request irq failed\n");
+               goto disable_clks;
+       }
+
+       otg->init = msm_otg_reset;
+       otg->set_host = msm_otg_set_host;
+       otg->set_peripheral = msm_otg_set_peripheral;
+
+       otg->io_ops = &msm_otg_io_ops;
+
+       ret = otg_set_transceiver(&motg->otg);
+       if (ret) {
+               dev_err(&pdev->dev, "otg_set_transceiver failed\n");
+               goto free_irq;
+       }
+
+       platform_set_drvdata(pdev, motg);
+       device_init_wakeup(&pdev->dev, 1);
+
+       if (motg->pdata->mode == USB_OTG &&
+                       motg->pdata->otg_control == OTG_USER_CONTROL) {
+               ret = msm_otg_debugfs_init(motg);
+               if (ret)
+                       dev_dbg(&pdev->dev, "mode debugfs file is"
+                                       "not available\n");
+       }
+
+       pm_runtime_set_active(&pdev->dev);
+       pm_runtime_enable(&pdev->dev);
+
+       return 0;
+free_irq:
+       free_irq(motg->irq, motg);
+disable_clks:
+       clk_disable(motg->pclk);
+       clk_disable(motg->clk);
+free_regs:
+       iounmap(motg->regs);
+put_core_clk:
+       if (motg->core_clk)
+               clk_put(motg->core_clk);
+       clk_put(motg->pclk);
+put_clk:
+       clk_put(motg->clk);
+put_phy_reset_clk:
+       clk_put(motg->phy_reset_clk);
+free_motg:
+       kfree(motg);
+       return ret;
+}
+
+static int __devexit msm_otg_remove(struct platform_device *pdev)
+{
+       struct msm_otg *motg = platform_get_drvdata(pdev);
+       struct otg_transceiver *otg = &motg->otg;
+       int cnt = 0;
+
+       if (otg->host || otg->gadget)
+               return -EBUSY;
+
+       msm_otg_debugfs_cleanup();
+       cancel_work_sync(&motg->sm_work);
+
+       msm_otg_resume(motg);
+
+       device_init_wakeup(&pdev->dev, 0);
+       pm_runtime_disable(&pdev->dev);
+
+       otg_set_transceiver(NULL);
+       free_irq(motg->irq, motg);
+
+       /*
+        * Put PHY in low power mode.
+        */
+       ulpi_read(otg, 0x14);
+       ulpi_write(otg, 0x08, 0x09);
+
+       writel(readl(USB_PORTSC) | PORTSC_PHCD, USB_PORTSC);
+       while (cnt < PHY_SUSPEND_TIMEOUT_USEC) {
+               if (readl(USB_PORTSC) & PORTSC_PHCD)
+                       break;
+               udelay(1);
+               cnt++;
+       }
+       if (cnt >= PHY_SUSPEND_TIMEOUT_USEC)
+               dev_err(otg->dev, "Unable to suspend PHY\n");
+
+       clk_disable(motg->pclk);
+       clk_disable(motg->clk);
+       if (motg->core_clk)
+               clk_disable(motg->core_clk);
+
+       iounmap(motg->regs);
+       pm_runtime_set_suspended(&pdev->dev);
+
+       clk_put(motg->phy_reset_clk);
+       clk_put(motg->pclk);
+       clk_put(motg->clk);
+       if (motg->core_clk)
+               clk_put(motg->core_clk);
+
+       kfree(motg);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM_RUNTIME
+static int msm_otg_runtime_idle(struct device *dev)
+{
+       struct msm_otg *motg = dev_get_drvdata(dev);
+       struct otg_transceiver *otg = &motg->otg;
+
+       dev_dbg(dev, "OTG runtime idle\n");
+
+       /*
+        * It is observed some times that a spurious interrupt
+        * comes when PHY is put into LPM immediately after PHY reset.
+        * This 1 sec delay also prevents entering into LPM immediately
+        * after asynchronous interrupt.
+        */
+       if (otg->state != OTG_STATE_UNDEFINED)
+               pm_schedule_suspend(dev, 1000);
+
+       return -EAGAIN;
+}
+
+static int msm_otg_runtime_suspend(struct device *dev)
+{
+       struct msm_otg *motg = dev_get_drvdata(dev);
+
+       dev_dbg(dev, "OTG runtime suspend\n");
+       return msm_otg_suspend(motg);
+}
+
+static int msm_otg_runtime_resume(struct device *dev)
+{
+       struct msm_otg *motg = dev_get_drvdata(dev);
+
+       dev_dbg(dev, "OTG runtime resume\n");
+       return msm_otg_resume(motg);
+}
+#else
+#define msm_otg_runtime_idle   NULL
+#define msm_otg_runtime_suspend        NULL
+#define msm_otg_runtime_resume NULL
+#endif
+
+#ifdef CONFIG_PM
+static int msm_otg_pm_suspend(struct device *dev)
+{
+       struct msm_otg *motg = dev_get_drvdata(dev);
+
+       dev_dbg(dev, "OTG PM suspend\n");
+       return msm_otg_suspend(motg);
+}
+
+static int msm_otg_pm_resume(struct device *dev)
+{
+       struct msm_otg *motg = dev_get_drvdata(dev);
+       int ret;
+
+       dev_dbg(dev, "OTG PM resume\n");
+
+       ret = msm_otg_resume(motg);
+       if (ret)
+               return ret;
+
+       /*
+        * Runtime PM Documentation recommends bringing the
+        * device to full powered state upon resume.
+        */
+       pm_runtime_disable(dev);
+       pm_runtime_set_active(dev);
+       pm_runtime_enable(dev);
+
+       return 0;
+}
+#else
+#define msm_otg_pm_suspend     NULL
+#define msm_otg_pm_resume      NULL
+#endif
+
+static const struct dev_pm_ops msm_otg_dev_pm_ops = {
+       .runtime_suspend = msm_otg_runtime_suspend,
+       .runtime_resume  = msm_otg_runtime_resume,
+       .runtime_idle    = msm_otg_runtime_idle,
+       .suspend         = msm_otg_pm_suspend,
+       .resume          = msm_otg_pm_resume,
+};
+
+static struct platform_driver msm_otg_driver = {
+       .remove = __devexit_p(msm_otg_remove),
+       .driver = {
+               .name = DRIVER_NAME,
+               .owner = THIS_MODULE,
+               .pm = &msm_otg_dev_pm_ops,
+       },
+};
+
+static int __init msm_otg_init(void)
+{
+       return platform_driver_probe(&msm_otg_driver, msm_otg_probe);
+}
+
+static void __exit msm_otg_exit(void)
+{
+       platform_driver_unregister(&msm_otg_driver);
+}
+
+module_init(msm_otg_init);
+module_exit(msm_otg_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MSM USB transceiver driver");