Initial import

1 files changed, 1830 insertions, 0 deletions

diff --git a/drivers/usb/phy/phy-msm-usb.c b/drivers/usb/phy/phy-msm-usb.c
new file mode 100644
index 000000000..c9156beea
--- /dev/null
+++ b/drivers/usb/phy/phy-msm-usb.c
@@ -0,0 +1,1830 @@
+/* Copyright (c) 2009-2011, 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/of.h>
+#include <linux/of_device.h>
+#include <linux/reset.h>
+
+#include <linux/usb.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/of.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 <linux/regulator/consumer.h>
+
+#define MSM_USB_BASE	(motg->regs)
+#define DRIVER_NAME	"msm_otg"
+
+#define ULPI_IO_TIMEOUT_USEC	(10 * 1000)
+#define LINK_RESET_TIMEOUT_USEC	(250 * 1000)
+
+#define USB_PHY_3P3_VOL_MIN	3050000 /* uV */
+#define USB_PHY_3P3_VOL_MAX	3300000 /* uV */
+#define USB_PHY_3P3_HPM_LOAD	50000	/* uA */
+#define USB_PHY_3P3_LPM_LOAD	4000	/* uA */
+
+#define USB_PHY_1P8_VOL_MIN	1800000 /* uV */
+#define USB_PHY_1P8_VOL_MAX	1800000 /* uV */
+#define USB_PHY_1P8_HPM_LOAD	50000	/* uA */
+#define USB_PHY_1P8_LPM_LOAD	4000	/* uA */
+
+#define USB_PHY_VDD_DIG_VOL_MIN	1000000 /* uV */
+#define USB_PHY_VDD_DIG_VOL_MAX	1320000 /* uV */
+#define USB_PHY_SUSP_DIG_VOL	500000  /* uV */
+
+enum vdd_levels {
+	VDD_LEVEL_NONE = 0,
+	VDD_LEVEL_MIN,
+	VDD_LEVEL_MAX,
+};
+
+static int msm_hsusb_init_vddcx(struct msm_otg *motg, int init)
+{
+	int ret = 0;
+
+	if (init) {
+		ret = regulator_set_voltage(motg->vddcx,
+				motg->vdd_levels[VDD_LEVEL_MIN],
+				motg->vdd_levels[VDD_LEVEL_MAX]);
+		if (ret) {
+			dev_err(motg->phy.dev, "Cannot set vddcx voltage\n");
+			return ret;
+		}
+
+		ret = regulator_enable(motg->vddcx);
+		if (ret)
+			dev_err(motg->phy.dev, "unable to enable hsusb vddcx\n");
+	} else {
+		ret = regulator_set_voltage(motg->vddcx, 0,
+				motg->vdd_levels[VDD_LEVEL_MAX]);
+		if (ret)
+			dev_err(motg->phy.dev, "Cannot set vddcx voltage\n");
+		ret = regulator_disable(motg->vddcx);
+		if (ret)
+			dev_err(motg->phy.dev, "unable to disable hsusb vddcx\n");
+	}
+
+	return ret;
+}
+
+static int msm_hsusb_ldo_init(struct msm_otg *motg, int init)
+{
+	int rc = 0;
+
+	if (init) {
+		rc = regulator_set_voltage(motg->v3p3, USB_PHY_3P3_VOL_MIN,
+				USB_PHY_3P3_VOL_MAX);
+		if (rc) {
+			dev_err(motg->phy.dev, "Cannot set v3p3 voltage\n");
+			goto exit;
+		}
+		rc = regulator_enable(motg->v3p3);
+		if (rc) {
+			dev_err(motg->phy.dev, "unable to enable the hsusb 3p3\n");
+			goto exit;
+		}
+		rc = regulator_set_voltage(motg->v1p8, USB_PHY_1P8_VOL_MIN,
+				USB_PHY_1P8_VOL_MAX);
+		if (rc) {
+			dev_err(motg->phy.dev, "Cannot set v1p8 voltage\n");
+			goto disable_3p3;
+		}
+		rc = regulator_enable(motg->v1p8);
+		if (rc) {
+			dev_err(motg->phy.dev, "unable to enable the hsusb 1p8\n");
+			goto disable_3p3;
+		}
+
+		return 0;
+	}
+
+	regulator_disable(motg->v1p8);
+disable_3p3:
+	regulator_disable(motg->v3p3);
+exit:
+	return rc;
+}
+
+static int msm_hsusb_ldo_set_mode(struct msm_otg *motg, int on)
+{
+	int ret = 0;
+
+	if (on) {
+		ret = regulator_set_load(motg->v1p8, USB_PHY_1P8_HPM_LOAD);
+		if (ret < 0) {
+			pr_err("Could not set HPM for v1p8\n");
+			return ret;
+		}
+		ret = regulator_set_load(motg->v3p3, USB_PHY_3P3_HPM_LOAD);
+		if (ret < 0) {
+			pr_err("Could not set HPM for v3p3\n");
+			regulator_set_load(motg->v1p8, USB_PHY_1P8_LPM_LOAD);
+			return ret;
+		}
+	} else {
+		ret = regulator_set_load(motg->v1p8, USB_PHY_1P8_LPM_LOAD);
+		if (ret < 0)
+			pr_err("Could not set LPM for v1p8\n");
+		ret = regulator_set_load(motg->v3p3, USB_PHY_3P3_LPM_LOAD);
+		if (ret < 0)
+			pr_err("Could not set LPM for v3p3\n");
+	}
+
+	pr_debug("reg (%s)\n", on ? "HPM" : "LPM");
+	return ret < 0 ? ret : 0;
+}
+
+static int ulpi_read(struct usb_phy *phy, u32 reg)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+	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(phy->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 usb_phy *phy, u32 val, u32 reg)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+	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(phy->dev, "ulpi_write: timeout\n");
+		return -ETIMEDOUT;
+	}
+	return 0;
+}
+
+static struct usb_phy_io_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, idx;
+	u32 addr = ULPI_EXT_VENDOR_SPECIFIC;
+
+	for (idx = 0; idx < pdata->phy_init_sz; idx++) {
+		if (seq[idx] == -1)
+			continue;
+
+		dev_vdbg(motg->phy.dev, "ulpi: write 0x%02x to 0x%02x\n",
+				seq[idx], addr + idx);
+		ulpi_write(&motg->phy, seq[idx], addr + idx);
+	}
+}
+
+static int msm_phy_notify_disconnect(struct usb_phy *phy,
+				   enum usb_device_speed speed)
+{
+	int val;
+
+	/*
+	 * Put the transceiver in non-driving mode. Otherwise host
+	 * may not detect soft-disconnection.
+	 */
+	val = ulpi_read(phy, ULPI_FUNC_CTRL);
+	val &= ~ULPI_FUNC_CTRL_OPMODE_MASK;
+	val |= ULPI_FUNC_CTRL_OPMODE_NONDRIVING;
+	ulpi_write(phy, val, ULPI_FUNC_CTRL);
+
+	return 0;
+}
+
+static int msm_otg_link_clk_reset(struct msm_otg *motg, bool assert)
+{
+	int ret;
+
+	if (assert)
+		ret = reset_control_assert(motg->link_rst);
+	else
+		ret = reset_control_deassert(motg->link_rst);
+
+	if (ret)
+		dev_err(motg->phy.dev, "usb link clk reset %s failed\n",
+			assert ? "assert" : "deassert");
+
+	return ret;
+}
+
+static int msm_otg_phy_clk_reset(struct msm_otg *motg)
+{
+	int ret = 0;
+
+	if (motg->phy_rst)
+		ret = reset_control_reset(motg->phy_rst);
+
+	if (ret)
+		dev_err(motg->phy.dev, "usb phy clk reset failed\n");
+
+	return ret;
+}
+
+static int msm_link_reset(struct msm_otg *motg)
+{
+	u32 val;
+	int ret;
+
+	ret = msm_otg_link_clk_reset(motg, 1);
+	if (ret)
+		return ret;
+
+	/* wait for 1ms delay as suggested in HPG. */
+	usleep_range(1000, 1200);
+
+	ret = msm_otg_link_clk_reset(motg, 0);
+	if (ret)
+		return ret;
+
+	if (motg->phy_number)
+		writel(readl(USB_PHY_CTRL2) | BIT(16), USB_PHY_CTRL2);
+
+	/* put transceiver in serial mode as part of reset */
+	val = readl(USB_PORTSC) & ~PORTSC_PTS_MASK;
+	writel(val | PORTSC_PTS_SERIAL, USB_PORTSC);
+
+	return 0;
+}
+
+static int msm_otg_reset(struct usb_phy *phy)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+	int cnt = 0;
+
+	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 and clear other status/control bits in PORTSC */
+	writel(PORTSC_PTS_ULPI, USB_PORTSC);
+
+	writel(0x0, USB_AHBBURST);
+	writel(0x08, USB_AHBMODE);
+
+	if (motg->phy_number)
+		writel(readl(USB_PHY_CTRL2) | BIT(16), USB_PHY_CTRL2);
+	return 0;
+}
+
+static void msm_phy_reset(struct msm_otg *motg)
+{
+	void __iomem *addr;
+
+	if (motg->pdata->phy_type != SNPS_28NM_INTEGRATED_PHY) {
+		msm_otg_phy_clk_reset(motg);
+		return;
+	}
+
+	addr = USB_PHY_CTRL;
+	if (motg->phy_number)
+		addr = USB_PHY_CTRL2;
+
+	/* Assert USB PHY_POR */
+	writel(readl(addr) | PHY_POR_ASSERT, addr);
+
+	/*
+	 * wait for minimum 10 microseconds as suggested in HPG.
+	 * Use a slightly larger value since the exact value didn't
+	 * work 100% of the time.
+	 */
+	udelay(12);
+
+	/* Deassert USB PHY_POR */
+	writel(readl(addr) & ~PHY_POR_ASSERT, addr);
+}
+
+static int msm_usb_reset(struct usb_phy *phy)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+	int ret;
+
+	if (!IS_ERR(motg->core_clk))
+		clk_prepare_enable(motg->core_clk);
+
+	ret = msm_link_reset(motg);
+	if (ret) {
+		dev_err(phy->dev, "phy_reset failed\n");
+		return ret;
+	}
+
+	ret = msm_otg_reset(&motg->phy);
+	if (ret) {
+		dev_err(phy->dev, "link reset failed\n");
+		return ret;
+	}
+
+	msleep(100);
+
+	/* Reset USB PHY after performing USB Link RESET */
+	msm_phy_reset(motg);
+
+	if (!IS_ERR(motg->core_clk))
+		clk_disable_unprepare(motg->core_clk);
+
+	return 0;
+}
+
+static int msm_phy_init(struct usb_phy *phy)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+	struct msm_otg_platform_data *pdata = motg->pdata;
+	u32 val, ulpi_val = 0;
+
+	/* Program USB PHY Override registers. */
+	ulpi_init(motg);
+
+	/*
+	 * It is recommended in HPG to reset USB PHY after programming
+	 * USB PHY Override registers.
+	 */
+	msm_phy_reset(motg);
+
+	if (pdata->otg_control == OTG_PHY_CONTROL) {
+		val = readl(USB_OTGSC);
+		if (pdata->mode == USB_DR_MODE_OTG) {
+			ulpi_val = ULPI_INT_IDGRD | ULPI_INT_SESS_VALID;
+			val |= OTGSC_IDIE | OTGSC_BSVIE;
+		} else if (pdata->mode == USB_DR_MODE_PERIPHERAL) {
+			ulpi_val = ULPI_INT_SESS_VALID;
+			val |= OTGSC_BSVIE;
+		}
+		writel(val, USB_OTGSC);
+		ulpi_write(phy, ulpi_val, ULPI_USB_INT_EN_RISE);
+		ulpi_write(phy, ulpi_val, ULPI_USB_INT_EN_FALL);
+	}
+
+	if (motg->phy_number)
+		writel(readl(USB_PHY_CTRL2) | BIT(16), USB_PHY_CTRL2);
+
+	return 0;
+}
+
+#define PHY_SUSPEND_TIMEOUT_USEC	(500 * 1000)
+#define PHY_RESUME_TIMEOUT_USEC	(100 * 1000)
+
+#ifdef CONFIG_PM
+
+static int msm_hsusb_config_vddcx(struct msm_otg *motg, int high)
+{
+	int max_vol = motg->vdd_levels[VDD_LEVEL_MAX];
+	int min_vol;
+	int ret;
+
+	if (high)
+		min_vol = motg->vdd_levels[VDD_LEVEL_MIN];
+	else
+		min_vol = motg->vdd_levels[VDD_LEVEL_NONE];
+
+	ret = regulator_set_voltage(motg->vddcx, min_vol, max_vol);
+	if (ret) {
+		pr_err("Cannot set vddcx voltage\n");
+		return ret;
+	}
+
+	pr_debug("%s: min_vol:%d max_vol:%d\n", __func__, min_vol, max_vol);
+
+	return ret;
+}
+
+static int msm_otg_suspend(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	struct usb_bus *bus = phy->otg->host;
+	struct msm_otg_platform_data *pdata = motg->pdata;
+	void __iomem *addr;
+	int cnt = 0;
+
+	if (atomic_read(&motg->in_lpm))
+		return 0;
+
+	disable_irq(motg->irq);
+	/*
+	 * Chipidea 45-nm PHY suspend sequence:
+	 *
+	 * 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).
+	 *
+	 * 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.
+	 *
+	 * PLL is not turned off when PHY enters into low power mode (LPM).
+	 * Disable PLL for maximum power savings.
+	 */
+
+	if (motg->pdata->phy_type == CI_45NM_INTEGRATED_PHY) {
+		ulpi_read(phy, 0x14);
+		if (pdata->otg_control == OTG_PHY_CONTROL)
+			ulpi_write(phy, 0x01, 0x30);
+		ulpi_write(phy, 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(phy->dev, "Unable to suspend PHY\n");
+		msm_otg_reset(phy);
+		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);
+
+	addr = USB_PHY_CTRL;
+	if (motg->phy_number)
+		addr = USB_PHY_CTRL2;
+
+	if (motg->pdata->phy_type == SNPS_28NM_INTEGRATED_PHY &&
+			motg->pdata->otg_control == OTG_PMIC_CONTROL)
+		writel(readl(addr) | PHY_RETEN, addr);
+
+	clk_disable_unprepare(motg->pclk);
+	clk_disable_unprepare(motg->clk);
+	if (!IS_ERR(motg->core_clk))
+		clk_disable_unprepare(motg->core_clk);
+
+	if (motg->pdata->phy_type == SNPS_28NM_INTEGRATED_PHY &&
+			motg->pdata->otg_control == OTG_PMIC_CONTROL) {
+		msm_hsusb_ldo_set_mode(motg, 0);
+		msm_hsusb_config_vddcx(motg, 0);
+	}
+
+	if (device_may_wakeup(phy->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(phy->dev, "USB in low power mode\n");
+
+	return 0;
+}
+
+static int msm_otg_resume(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	struct usb_bus *bus = phy->otg->host;
+	void __iomem *addr;
+	int cnt = 0;
+	unsigned temp;
+
+	if (!atomic_read(&motg->in_lpm))
+		return 0;
+
+	clk_prepare_enable(motg->pclk);
+	clk_prepare_enable(motg->clk);
+	if (!IS_ERR(motg->core_clk))
+		clk_prepare_enable(motg->core_clk);
+
+	if (motg->pdata->phy_type == SNPS_28NM_INTEGRATED_PHY &&
+			motg->pdata->otg_control == OTG_PMIC_CONTROL) {
+
+		addr = USB_PHY_CTRL;
+		if (motg->phy_number)
+			addr = USB_PHY_CTRL2;
+
+		msm_hsusb_ldo_set_mode(motg, 1);
+		msm_hsusb_config_vddcx(motg, 1);
+		writel(readl(addr) & ~PHY_RETEN, addr);
+	}
+
+	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(phy->dev, "Unable to resume USB. Re-plugin the cable\n");
+		msm_otg_reset(phy);
+	}
+
+skip_phy_resume:
+	if (device_may_wakeup(phy->dev))
+		disable_irq_wake(motg->irq);
+	if (bus)
+		set_bit(HCD_FLAG_HW_ACCESSIBLE, &(bus_to_hcd(bus))->flags);
+
+	atomic_set(&motg->in_lpm, 0);
+
+	if (motg->async_int) {
+		motg->async_int = 0;
+		pm_runtime_put(phy->dev);
+		enable_irq(motg->irq);
+	}
+
+	dev_info(phy->dev, "USB exited from low power mode\n");
+
+	return 0;
+}
+#endif
+
+static void msm_otg_notify_charger(struct msm_otg *motg, unsigned mA)
+{
+	if (motg->cur_power == mA)
+		return;
+
+	/* TODO: Notify PMIC about available current */
+	dev_info(motg->phy.dev, "Avail curr from USB = %u\n", mA);
+	motg->cur_power = mA;
+}
+
+static int msm_otg_set_power(struct usb_phy *phy, unsigned mA)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+
+	/*
+	 * Gadget driver uses set_power method to notify about the
+	 * available current based on suspend/configured states.
+	 *
+	 * IDEV_CHG can be drawn irrespective of suspend/un-configured
+	 * states when CDP/ACA is connected.
+	 */
+	if (motg->chg_type == USB_SDP_CHARGER)
+		msm_otg_notify_charger(motg, mA);
+
+	return 0;
+}
+
+static void msm_otg_start_host(struct usb_phy *phy, int on)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+	struct msm_otg_platform_data *pdata = motg->pdata;
+	struct usb_hcd *hcd;
+
+	if (!phy->otg->host)
+		return;
+
+	hcd = bus_to_hcd(phy->otg->host);
+
+	if (on) {
+		dev_dbg(phy->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);
+		device_wakeup_enable(hcd->self.controller);
+#endif
+	} else {
+		dev_dbg(phy->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 usb_otg *otg, struct usb_bus *host)
+{
+	struct msm_otg *motg = container_of(otg->usb_phy, struct msm_otg, phy);
+	struct usb_hcd *hcd;
+
+	/*
+	 * Fail host registration if this board can support
+	 * only peripheral configuration.
+	 */
+	if (motg->pdata->mode == USB_DR_MODE_PERIPHERAL) {
+		dev_info(otg->usb_phy->dev, "Host mode is not supported\n");
+		return -ENODEV;
+	}
+
+	if (!host) {
+		if (otg->state == OTG_STATE_A_HOST) {
+			pm_runtime_get_sync(otg->usb_phy->dev);
+			msm_otg_start_host(otg->usb_phy, 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->usb_phy->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_DR_MODE_HOST || otg->gadget) {
+		pm_runtime_get_sync(otg->usb_phy->dev);
+		schedule_work(&motg->sm_work);
+	}
+
+	return 0;
+}
+
+static void msm_otg_start_peripheral(struct usb_phy *phy, int on)
+{
+	struct msm_otg *motg = container_of(phy, struct msm_otg, phy);
+	struct msm_otg_platform_data *pdata = motg->pdata;
+
+	if (!phy->otg->gadget)
+		return;
+
+	if (on) {
+		dev_dbg(phy->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(phy->otg->gadget);
+	} else {
+		dev_dbg(phy->dev, "gadget off\n");
+		usb_gadget_vbus_disconnect(phy->otg->gadget);
+		if (pdata->setup_gpio)
+			pdata->setup_gpio(OTG_STATE_UNDEFINED);
+	}
+
+}
+
+static int msm_otg_set_peripheral(struct usb_otg *otg,
+					struct usb_gadget *gadget)
+{
+	struct msm_otg *motg = container_of(otg->usb_phy, struct msm_otg, phy);
+
+	/*
+	 * Fail peripheral registration if this board can support
+	 * only host configuration.
+	 */
+	if (motg->pdata->mode == USB_DR_MODE_HOST) {
+		dev_info(otg->usb_phy->dev, "Peripheral mode is not supported\n");
+		return -ENODEV;
+	}
+
+	if (!gadget) {
+		if (otg->state == OTG_STATE_B_PERIPHERAL) {
+			pm_runtime_get_sync(otg->usb_phy->dev);
+			msm_otg_start_peripheral(otg->usb_phy, 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->usb_phy->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_DR_MODE_PERIPHERAL || otg->host) {
+		pm_runtime_get_sync(otg->usb_phy->dev);
+		schedule_work(&motg->sm_work);
+	}
+
+	return 0;
+}
+
+static bool msm_chg_check_secondary_det(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 chg_det;
+	bool ret = false;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		ret = chg_det & (1 << 4);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x87);
+		ret = chg_det & 1;
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
+static void msm_chg_enable_secondary_det(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 chg_det;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		/* Turn off charger block */
+		chg_det |= ~(1 << 1);
+		ulpi_write(phy, chg_det, 0x34);
+		udelay(20);
+		/* control chg block via ULPI */
+		chg_det &= ~(1 << 3);
+		ulpi_write(phy, chg_det, 0x34);
+		/* put it in host mode for enabling D- source */
+		chg_det &= ~(1 << 2);
+		ulpi_write(phy, chg_det, 0x34);
+		/* Turn on chg detect block */
+		chg_det &= ~(1 << 1);
+		ulpi_write(phy, chg_det, 0x34);
+		udelay(20);
+		/* enable chg detection */
+		chg_det &= ~(1 << 0);
+		ulpi_write(phy, chg_det, 0x34);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		/*
+		 * Configure DM as current source, DP as current sink
+		 * and enable battery charging comparators.
+		 */
+		ulpi_write(phy, 0x8, 0x85);
+		ulpi_write(phy, 0x2, 0x85);
+		ulpi_write(phy, 0x1, 0x85);
+		break;
+	default:
+		break;
+	}
+}
+
+static bool msm_chg_check_primary_det(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 chg_det;
+	bool ret = false;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		ret = chg_det & (1 << 4);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x87);
+		ret = chg_det & 1;
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
+static void msm_chg_enable_primary_det(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 chg_det;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		/* enable chg detection */
+		chg_det &= ~(1 << 0);
+		ulpi_write(phy, chg_det, 0x34);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		/*
+		 * Configure DP as current source, DM as current sink
+		 * and enable battery charging comparators.
+		 */
+		ulpi_write(phy, 0x2, 0x85);
+		ulpi_write(phy, 0x1, 0x85);
+		break;
+	default:
+		break;
+	}
+}
+
+static bool msm_chg_check_dcd(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 line_state;
+	bool ret = false;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		line_state = ulpi_read(phy, 0x15);
+		ret = !(line_state & 1);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		line_state = ulpi_read(phy, 0x87);
+		ret = line_state & 2;
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
+static void msm_chg_disable_dcd(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 chg_det;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		chg_det &= ~(1 << 5);
+		ulpi_write(phy, chg_det, 0x34);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		ulpi_write(phy, 0x10, 0x86);
+		break;
+	default:
+		break;
+	}
+}
+
+static void msm_chg_enable_dcd(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 chg_det;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		/* Turn on D+ current source */
+		chg_det |= (1 << 5);
+		ulpi_write(phy, chg_det, 0x34);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		/* Data contact detection enable */
+		ulpi_write(phy, 0x10, 0x85);
+		break;
+	default:
+		break;
+	}
+}
+
+static void msm_chg_block_on(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 func_ctrl, chg_det;
+
+	/* put the controller in non-driving mode */
+	func_ctrl = ulpi_read(phy, ULPI_FUNC_CTRL);
+	func_ctrl &= ~ULPI_FUNC_CTRL_OPMODE_MASK;
+	func_ctrl |= ULPI_FUNC_CTRL_OPMODE_NONDRIVING;
+	ulpi_write(phy, func_ctrl, ULPI_FUNC_CTRL);
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		/* control chg block via ULPI */
+		chg_det &= ~(1 << 3);
+		ulpi_write(phy, chg_det, 0x34);
+		/* Turn on chg detect block */
+		chg_det &= ~(1 << 1);
+		ulpi_write(phy, chg_det, 0x34);
+		udelay(20);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		/* Clear charger detecting control bits */
+		ulpi_write(phy, 0x3F, 0x86);
+		/* Clear alt interrupt latch and enable bits */
+		ulpi_write(phy, 0x1F, 0x92);
+		ulpi_write(phy, 0x1F, 0x95);
+		udelay(100);
+		break;
+	default:
+		break;
+	}
+}
+
+static void msm_chg_block_off(struct msm_otg *motg)
+{
+	struct usb_phy *phy = &motg->phy;
+	u32 func_ctrl, chg_det;
+
+	switch (motg->pdata->phy_type) {
+	case CI_45NM_INTEGRATED_PHY:
+		chg_det = ulpi_read(phy, 0x34);
+		/* Turn off charger block */
+		chg_det |= ~(1 << 1);
+		ulpi_write(phy, chg_det, 0x34);
+		break;
+	case SNPS_28NM_INTEGRATED_PHY:
+		/* Clear charger detecting control bits */
+		ulpi_write(phy, 0x3F, 0x86);
+		/* Clear alt interrupt latch and enable bits */
+		ulpi_write(phy, 0x1F, 0x92);
+		ulpi_write(phy, 0x1F, 0x95);
+		break;
+	default:
+		break;
+	}
+
+	/* put the controller in normal mode */
+	func_ctrl = ulpi_read(phy, ULPI_FUNC_CTRL);
+	func_ctrl &= ~ULPI_FUNC_CTRL_OPMODE_MASK;
+	func_ctrl |= ULPI_FUNC_CTRL_OPMODE_NORMAL;
+	ulpi_write(phy, func_ctrl, ULPI_FUNC_CTRL);
+}
+
+#define MSM_CHG_DCD_POLL_TIME		(100 * HZ/1000) /* 100 msec */
+#define MSM_CHG_DCD_MAX_RETRIES		6 /* Tdcd_tmout = 6 * 100 msec */
+#define MSM_CHG_PRIMARY_DET_TIME	(40 * HZ/1000) /* TVDPSRC_ON */
+#define MSM_CHG_SECONDARY_DET_TIME	(40 * HZ/1000) /* TVDMSRC_ON */
+static void msm_chg_detect_work(struct work_struct *w)
+{
+	struct msm_otg *motg = container_of(w, struct msm_otg, chg_work.work);
+	struct usb_phy *phy = &motg->phy;
+	bool is_dcd, tmout, vout;
+	unsigned long delay;
+
+	dev_dbg(phy->dev, "chg detection work\n");
+	switch (motg->chg_state) {
+	case USB_CHG_STATE_UNDEFINED:
+		pm_runtime_get_sync(phy->dev);
+		msm_chg_block_on(motg);
+		msm_chg_enable_dcd(motg);
+		motg->chg_state = USB_CHG_STATE_WAIT_FOR_DCD;
+		motg->dcd_retries = 0;
+		delay = MSM_CHG_DCD_POLL_TIME;
+		break;
+	case USB_CHG_STATE_WAIT_FOR_DCD:
+		is_dcd = msm_chg_check_dcd(motg);
+		tmout = ++motg->dcd_retries == MSM_CHG_DCD_MAX_RETRIES;
+		if (is_dcd || tmout) {
+			msm_chg_disable_dcd(motg);
+			msm_chg_enable_primary_det(motg);
+			delay = MSM_CHG_PRIMARY_DET_TIME;
+			motg->chg_state = USB_CHG_STATE_DCD_DONE;
+		} else {
+			delay = MSM_CHG_DCD_POLL_TIME;
+		}
+		break;
+	case USB_CHG_STATE_DCD_DONE:
+		vout = msm_chg_check_primary_det(motg);
+		if (vout) {
+			msm_chg_enable_secondary_det(motg);
+			delay = MSM_CHG_SECONDARY_DET_TIME;
+			motg->chg_state = USB_CHG_STATE_PRIMARY_DONE;
+		} else {
+			motg->chg_type = USB_SDP_CHARGER;
+			motg->chg_state = USB_CHG_STATE_DETECTED;
+			delay = 0;
+		}
+		break;
+	case USB_CHG_STATE_PRIMARY_DONE:
+		vout = msm_chg_check_secondary_det(motg);
+		if (vout)
+			motg->chg_type = USB_DCP_CHARGER;
+		else
+			motg->chg_type = USB_CDP_CHARGER;
+		motg->chg_state = USB_CHG_STATE_SECONDARY_DONE;
+		/* fall through */
+	case USB_CHG_STATE_SECONDARY_DONE:
+		motg->chg_state = USB_CHG_STATE_DETECTED;
+	case USB_CHG_STATE_DETECTED:
+		msm_chg_block_off(motg);
+		dev_dbg(phy->dev, "charger = %d\n", motg->chg_type);
+		schedule_work(&motg->sm_work);
+		return;
+	default:
+		return;
+	}
+
+	schedule_delayed_work(&motg->chg_work, delay);
+}
+
+/*
+ * 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_DR_MODE_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) {
+				set_bit(ID, &motg->inputs);
+				clear_bit(B_SESS_VLD, &motg->inputs);
+		}
+		break;
+	case USB_DR_MODE_HOST:
+		clear_bit(ID, &motg->inputs);
+		break;
+	case USB_DR_MODE_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 usb_otg *otg = motg->phy.otg;
+
+	switch (otg->state) {
+	case OTG_STATE_UNDEFINED:
+		dev_dbg(otg->usb_phy->dev, "OTG_STATE_UNDEFINED state\n");
+		msm_otg_reset(otg->usb_phy);
+		msm_otg_init_sm(motg);
+		otg->state = OTG_STATE_B_IDLE;
+		/* FALL THROUGH */
+	case OTG_STATE_B_IDLE:
+		dev_dbg(otg->usb_phy->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->usb_phy, 1);
+			otg->state = OTG_STATE_A_HOST;
+		} else if (test_bit(B_SESS_VLD, &motg->inputs)) {
+			switch (motg->chg_state) {
+			case USB_CHG_STATE_UNDEFINED:
+				msm_chg_detect_work(&motg->chg_work.work);
+				break;
+			case USB_CHG_STATE_DETECTED:
+				switch (motg->chg_type) {
+				case USB_DCP_CHARGER:
+					msm_otg_notify_charger(motg,
+							IDEV_CHG_MAX);
+					break;
+				case USB_CDP_CHARGER:
+					msm_otg_notify_charger(motg,
+							IDEV_CHG_MAX);
+					msm_otg_start_peripheral(otg->usb_phy,
+								 1);
+					otg->state
+						= OTG_STATE_B_PERIPHERAL;
+					break;
+				case USB_SDP_CHARGER:
+					msm_otg_notify_charger(motg, IUNIT);
+					msm_otg_start_peripheral(otg->usb_phy,
+								 1);
+					otg->state
+						= OTG_STATE_B_PERIPHERAL;
+					break;
+				default:
+					break;
+				}
+				break;
+			default:
+				break;
+			}
+		} else {
+			/*
+			 * If charger detection work is pending, decrement
+			 * the pm usage counter to balance with the one that
+			 * is incremented in charger detection work.
+			 */
+			if (cancel_delayed_work_sync(&motg->chg_work)) {
+				pm_runtime_put_sync(otg->usb_phy->dev);
+				msm_otg_reset(otg->usb_phy);
+			}
+			msm_otg_notify_charger(motg, 0);
+			motg->chg_state = USB_CHG_STATE_UNDEFINED;
+			motg->chg_type = USB_INVALID_CHARGER;
+		}
+
+		if (otg->state == OTG_STATE_B_IDLE)
+			pm_runtime_put_sync(otg->usb_phy->dev);
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		dev_dbg(otg->usb_phy->dev, "OTG_STATE_B_PERIPHERAL state\n");
+		if (!test_bit(B_SESS_VLD, &motg->inputs) ||
+				!test_bit(ID, &motg->inputs)) {
+			msm_otg_notify_charger(motg, 0);
+			msm_otg_start_peripheral(otg->usb_phy, 0);
+			motg->chg_state = USB_CHG_STATE_UNDEFINED;
+			motg->chg_type = USB_INVALID_CHARGER;
+			otg->state = OTG_STATE_B_IDLE;
+			msm_otg_reset(otg->usb_phy);
+			schedule_work(w);
+		}
+		break;
+	case OTG_STATE_A_HOST:
+		dev_dbg(otg->usb_phy->dev, "OTG_STATE_A_HOST state\n");
+		if (test_bit(ID, &motg->inputs)) {
+			msm_otg_start_host(otg->usb_phy, 0);
+			otg->state = OTG_STATE_B_IDLE;
+			msm_otg_reset(otg->usb_phy);
+			schedule_work(w);
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+static irqreturn_t msm_otg_irq(int irq, void *data)
+{
+	struct msm_otg *motg = data;
+	struct usb_phy *phy = &motg->phy;
+	u32 otgsc = 0;
+
+	if (atomic_read(&motg->in_lpm)) {
+		disable_irq_nosync(irq);
+		motg->async_int = 1;
+		pm_runtime_get(phy->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(phy->dev, "ID set/clear\n");
+		pm_runtime_get_noresume(phy->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(phy->dev, "BSV set/clear\n");
+		pm_runtime_get_noresume(phy->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 usb_otg *otg = motg->phy.otg;
+
+	switch (otg->state) {
+	case OTG_STATE_A_HOST:
+		seq_puts(s, "host\n");
+		break;
+	case OTG_STATE_B_PERIPHERAL:
+		seq_puts(s, "peripheral\n");
+		break;
+	default:
+		seq_puts(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 seq_file *s = file->private_data;
+	struct msm_otg *motg = s->private;
+	char buf[16];
+	struct usb_otg *otg = motg->phy.otg;
+	int status = count;
+	enum usb_dr_mode 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_DR_MODE_HOST;
+	} else if (!strncmp(buf, "peripheral", 10)) {
+		req_mode = USB_DR_MODE_PERIPHERAL;
+	} else if (!strncmp(buf, "none", 4)) {
+		req_mode = USB_DR_MODE_UNKNOWN;
+	} else {
+		status = -EINVAL;
+		goto out;
+	}
+
+	switch (req_mode) {
+	case USB_DR_MODE_UNKNOWN:
+		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_DR_MODE_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_DR_MODE_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->usb_phy->dev);
+	schedule_work(&motg->sm_work);
+out:
+	return status;
+}
+
+static 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 const struct of_device_id msm_otg_dt_match[] = {
+	{
+		.compatible = "qcom,usb-otg-ci",
+		.data = (void *) CI_45NM_INTEGRATED_PHY
+	},
+	{
+		.compatible = "qcom,usb-otg-snps",
+		.data = (void *) SNPS_28NM_INTEGRATED_PHY
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, msm_otg_dt_match);
+
+static int msm_otg_read_dt(struct platform_device *pdev, struct msm_otg *motg)
+{
+	struct msm_otg_platform_data *pdata;
+	const struct of_device_id *id;
+	struct device_node *node = pdev->dev.of_node;
+	struct property *prop;
+	int len, ret, words;
+	u32 val, tmp[3];
+
+	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	motg->pdata = pdata;
+
+	id = of_match_device(msm_otg_dt_match, &pdev->dev);
+	pdata->phy_type = (enum msm_usb_phy_type) id->data;
+
+	motg->link_rst = devm_reset_control_get(&pdev->dev, "link");
+	if (IS_ERR(motg->link_rst))
+		return PTR_ERR(motg->link_rst);
+
+	motg->phy_rst = devm_reset_control_get(&pdev->dev, "phy");
+	if (IS_ERR(motg->phy_rst))
+		motg->phy_rst = NULL;
+
+	pdata->mode = of_usb_get_dr_mode(node);
+	if (pdata->mode == USB_DR_MODE_UNKNOWN)
+		pdata->mode = USB_DR_MODE_OTG;
+
+	pdata->otg_control = OTG_PHY_CONTROL;
+	if (!of_property_read_u32(node, "qcom,otg-control", &val))
+		if (val == OTG_PMIC_CONTROL)
+			pdata->otg_control = val;
+
+	if (!of_property_read_u32(node, "qcom,phy-num", &val) && val < 2)
+		motg->phy_number = val;
+
+	motg->vdd_levels[VDD_LEVEL_NONE] = USB_PHY_SUSP_DIG_VOL;
+	motg->vdd_levels[VDD_LEVEL_MIN] = USB_PHY_VDD_DIG_VOL_MIN;
+	motg->vdd_levels[VDD_LEVEL_MAX] = USB_PHY_VDD_DIG_VOL_MAX;
+
+	if (of_get_property(node, "qcom,vdd-levels", &len) &&
+	    len == sizeof(tmp)) {
+		of_property_read_u32_array(node, "qcom,vdd-levels",
+					   tmp, len / sizeof(*tmp));
+		motg->vdd_levels[VDD_LEVEL_NONE] = tmp[VDD_LEVEL_NONE];
+		motg->vdd_levels[VDD_LEVEL_MIN] = tmp[VDD_LEVEL_MIN];
+		motg->vdd_levels[VDD_LEVEL_MAX] = tmp[VDD_LEVEL_MAX];
+	}
+
+	prop = of_find_property(node, "qcom,phy-init-sequence", &len);
+	if (!prop || !len)
+		return 0;
+
+	words = len / sizeof(u32);
+
+	if (words >= ULPI_EXT_VENDOR_SPECIFIC) {
+		dev_warn(&pdev->dev, "Too big PHY init sequence %d\n", words);
+		return 0;
+	}
+
+	pdata->phy_init_seq = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
+	if (!pdata->phy_init_seq)
+		return 0;
+
+	ret = of_property_read_u32_array(node, "qcom,phy-init-sequence",
+					 pdata->phy_init_seq, words);
+	if (!ret)
+		pdata->phy_init_sz = words;
+
+	return 0;
+}
+
+static int msm_otg_probe(struct platform_device *pdev)
+{
+	struct regulator_bulk_data regs[3];
+	int ret = 0;
+	struct device_node *np = pdev->dev.of_node;
+	struct msm_otg_platform_data *pdata;
+	struct resource *res;
+	struct msm_otg *motg;
+	struct usb_phy *phy;
+	void __iomem *phy_select;
+
+	motg = devm_kzalloc(&pdev->dev, sizeof(struct msm_otg), GFP_KERNEL);
+	if (!motg)
+		return -ENOMEM;
+
+	pdata = dev_get_platdata(&pdev->dev);
+	if (!pdata) {
+		if (!np)
+			return -ENXIO;
+		ret = msm_otg_read_dt(pdev, motg);
+		if (ret)
+			return ret;
+	}
+
+	motg->phy.otg = devm_kzalloc(&pdev->dev, sizeof(struct usb_otg),
+				     GFP_KERNEL);
+	if (!motg->phy.otg)
+		return -ENOMEM;
+
+	phy = &motg->phy;
+	phy->dev = &pdev->dev;
+
+	motg->clk = devm_clk_get(&pdev->dev, np ? "core" : "usb_hs_clk");
+	if (IS_ERR(motg->clk)) {
+		dev_err(&pdev->dev, "failed to get usb_hs_clk\n");
+		return PTR_ERR(motg->clk);
+	}
+
+	/*
+	 * If USB Core is running its protocol engine based on CORE CLK,
+	 * CORE CLK  must be running at >55Mhz for correct HSUSB
+	 * operation and USB core cannot tolerate frequency changes on
+	 * CORE CLK.
+	 */
+	motg->pclk = devm_clk_get(&pdev->dev, np ? "iface" : "usb_hs_pclk");
+	if (IS_ERR(motg->pclk)) {
+		dev_err(&pdev->dev, "failed to get usb_hs_pclk\n");
+		return PTR_ERR(motg->pclk);
+	}
+
+	/*
+	 * 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 = devm_clk_get(&pdev->dev,
+				      np ? "alt_core" : "usb_hs_core_clk");
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -EINVAL;
+	motg->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+	if (!motg->regs)
+		return -ENOMEM;
+
+	/*
+	 * NOTE: The PHYs can be multiplexed between the chipidea controller
+	 * and the dwc3 controller, using a single bit. It is important that
+	 * the dwc3 driver does not set this bit in an incompatible way.
+	 */
+	if (motg->phy_number) {
+		phy_select = devm_ioremap_nocache(&pdev->dev, USB2_PHY_SEL, 4);
+		if (!phy_select)
+			return -ENOMEM;
+		/* Enable second PHY with the OTG port */
+		writel(0x1, phy_select);
+	}
+
+	dev_info(&pdev->dev, "OTG regs = %p\n", motg->regs);
+
+	motg->irq = platform_get_irq(pdev, 0);
+	if (motg->irq < 0) {
+		dev_err(&pdev->dev, "platform_get_irq failed\n");
+		return motg->irq;
+	}
+
+	regs[0].supply = "vddcx";
+	regs[1].supply = "v3p3";
+	regs[2].supply = "v1p8";
+
+	ret = devm_regulator_bulk_get(motg->phy.dev, ARRAY_SIZE(regs), regs);
+	if (ret)
+		return ret;
+
+	motg->vddcx = regs[0].consumer;
+	motg->v3p3  = regs[1].consumer;
+	motg->v1p8  = regs[2].consumer;
+
+	clk_set_rate(motg->clk, 60000000);
+
+	clk_prepare_enable(motg->clk);
+	clk_prepare_enable(motg->pclk);
+
+	if (!IS_ERR(motg->core_clk))
+		clk_prepare_enable(motg->core_clk);
+
+	ret = msm_hsusb_init_vddcx(motg, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "hsusb vddcx configuration failed\n");
+		goto disable_clks;
+	}
+
+	ret = msm_hsusb_ldo_init(motg, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "hsusb vreg configuration failed\n");
+		goto disable_vddcx;
+	}
+	ret = msm_hsusb_ldo_set_mode(motg, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "hsusb vreg enable failed\n");
+		goto disable_ldo;
+	}
+
+	writel(0, USB_USBINTR);
+	writel(0, USB_OTGSC);
+
+	INIT_WORK(&motg->sm_work, msm_otg_sm_work);
+	INIT_DELAYED_WORK(&motg->chg_work, msm_chg_detect_work);
+	ret = devm_request_irq(&pdev->dev, motg->irq, msm_otg_irq, IRQF_SHARED,
+					"msm_otg", motg);
+	if (ret) {
+		dev_err(&pdev->dev, "request irq failed\n");
+		goto disable_ldo;
+	}
+
+	phy->init = msm_phy_init;
+	phy->set_power = msm_otg_set_power;
+	phy->notify_disconnect = msm_phy_notify_disconnect;
+	phy->type = USB_PHY_TYPE_USB2;
+
+	phy->io_ops = &msm_otg_io_ops;
+
+	phy->otg->usb_phy = &motg->phy;
+	phy->otg->set_host = msm_otg_set_host;
+	phy->otg->set_peripheral = msm_otg_set_peripheral;
+
+	msm_usb_reset(phy);
+
+	ret = usb_add_phy_dev(&motg->phy);
+	if (ret) {
+		dev_err(&pdev->dev, "usb_add_phy failed\n");
+		goto disable_ldo;
+	}
+
+	platform_set_drvdata(pdev, motg);
+	device_init_wakeup(&pdev->dev, 1);
+
+	if (motg->pdata->mode == USB_DR_MODE_OTG &&
+		motg->pdata->otg_control == OTG_USER_CONTROL) {
+		ret = msm_otg_debugfs_init(motg);
+		if (ret)
+			dev_dbg(&pdev->dev, "Can not create mode change file\n");
+	}
+
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
+
+disable_ldo:
+	msm_hsusb_ldo_init(motg, 0);
+disable_vddcx:
+	msm_hsusb_init_vddcx(motg, 0);
+disable_clks:
+	clk_disable_unprepare(motg->pclk);
+	clk_disable_unprepare(motg->clk);
+	if (!IS_ERR(motg->core_clk))
+		clk_disable_unprepare(motg->core_clk);
+	return ret;
+}
+
+static int msm_otg_remove(struct platform_device *pdev)
+{
+	struct msm_otg *motg = platform_get_drvdata(pdev);
+	struct usb_phy *phy = &motg->phy;
+	int cnt = 0;
+
+	if (phy->otg->host || phy->otg->gadget)
+		return -EBUSY;
+
+	msm_otg_debugfs_cleanup();
+	cancel_delayed_work_sync(&motg->chg_work);
+	cancel_work_sync(&motg->sm_work);
+
+	pm_runtime_resume(&pdev->dev);
+
+	device_init_wakeup(&pdev->dev, 0);
+	pm_runtime_disable(&pdev->dev);
+
+	usb_remove_phy(phy);
+	disable_irq(motg->irq);
+
+	/*
+	 * Put PHY in low power mode.
+	 */
+	ulpi_read(phy, 0x14);
+	ulpi_write(phy, 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(phy->dev, "Unable to suspend PHY\n");
+
+	clk_disable_unprepare(motg->pclk);
+	clk_disable_unprepare(motg->clk);
+	if (!IS_ERR(motg->core_clk))
+		clk_disable_unprepare(motg->core_clk);
+	msm_hsusb_ldo_init(motg, 0);
+
+	pm_runtime_set_suspended(&pdev->dev);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int msm_otg_runtime_idle(struct device *dev)
+{
+	struct msm_otg *motg = dev_get_drvdata(dev);
+	struct usb_otg *otg = motg->phy.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);
+}
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+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;
+}
+#endif
+
+static const struct dev_pm_ops msm_otg_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(msm_otg_pm_suspend, msm_otg_pm_resume)
+	SET_RUNTIME_PM_OPS(msm_otg_runtime_suspend, msm_otg_runtime_resume,
+				msm_otg_runtime_idle)
+};
+
+static struct platform_driver msm_otg_driver = {
+	.probe = msm_otg_probe,
+	.remove = msm_otg_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.pm = &msm_otg_dev_pm_ops,
+		.of_match_table = msm_otg_dt_match,
+	},
+};
+
+module_platform_driver(msm_otg_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MSM USB transceiver driver");