/**
   * omap-usb-host.c - The USBHS core driver for OMAP EHCI & OHCI
   *

   * Copyright (C) 2011-2013 Texas Instruments Incorporated - http://www.ti.com

   * Author: Keshava Munegowda <keshava_mgowda@ti.com>

   * Author: Roger Quadros <rogerq@ti.com>

   *
   * This program is free software: you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2  of
   * the License 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, see <http://www.gnu.org/licenses/>.
   */
  #include <linux/kernel.h>

  #include <linux/module.h>

  #include <linux/types.h>
  #include <linux/slab.h>
  #include <linux/delay.h>

  #include <linux/clk.h>
  #include <linux/dma-mapping.h>

  #include <linux/gpio.h>

  #include <linux/platform_device.h>
  #include <linux/platform_data/usb-omap.h>

  #include <linux/pm_runtime.h>

  #include <linux/of.h>
  #include <linux/of_platform.h>

  #include <linux/err.h>

  #include "omap-usb.h"

  #define USBHS_DRIVER_NAME	"usbhs_omap"

  #define OMAP_EHCI_DEVICE	"ehci-omap"
  #define OMAP_OHCI_DEVICE	"ohci-omap3"
  
  /* OMAP USBHOST Register addresses  */

  /* UHH Register Set */
  #define	OMAP_UHH_REVISION				(0x00)
  #define	OMAP_UHH_SYSCONFIG				(0x10)
  #define	OMAP_UHH_SYSCONFIG_MIDLEMODE			(1 << 12)
  #define	OMAP_UHH_SYSCONFIG_CACTIVITY			(1 << 8)
  #define	OMAP_UHH_SYSCONFIG_SIDLEMODE			(1 << 3)
  #define	OMAP_UHH_SYSCONFIG_ENAWAKEUP			(1 << 2)
  #define	OMAP_UHH_SYSCONFIG_SOFTRESET			(1 << 1)
  #define	OMAP_UHH_SYSCONFIG_AUTOIDLE			(1 << 0)
  
  #define	OMAP_UHH_SYSSTATUS				(0x14)
  #define	OMAP_UHH_HOSTCONFIG				(0x40)
  #define	OMAP_UHH_HOSTCONFIG_ULPI_BYPASS			(1 << 0)
  #define	OMAP_UHH_HOSTCONFIG_ULPI_P1_BYPASS		(1 << 0)
  #define	OMAP_UHH_HOSTCONFIG_ULPI_P2_BYPASS		(1 << 11)
  #define	OMAP_UHH_HOSTCONFIG_ULPI_P3_BYPASS		(1 << 12)
  #define OMAP_UHH_HOSTCONFIG_INCR4_BURST_EN		(1 << 2)
  #define OMAP_UHH_HOSTCONFIG_INCR8_BURST_EN		(1 << 3)
  #define OMAP_UHH_HOSTCONFIG_INCR16_BURST_EN		(1 << 4)
  #define OMAP_UHH_HOSTCONFIG_INCRX_ALIGN_EN		(1 << 5)
  #define OMAP_UHH_HOSTCONFIG_P1_CONNECT_STATUS		(1 << 8)
  #define OMAP_UHH_HOSTCONFIG_P2_CONNECT_STATUS		(1 << 9)
  #define OMAP_UHH_HOSTCONFIG_P3_CONNECT_STATUS		(1 << 10)
  #define OMAP4_UHH_HOSTCONFIG_APP_START_CLK		(1 << 31)
  
  /* OMAP4-specific defines */
  #define OMAP4_UHH_SYSCONFIG_IDLEMODE_CLEAR		(3 << 2)
  #define OMAP4_UHH_SYSCONFIG_NOIDLE			(1 << 2)
  #define OMAP4_UHH_SYSCONFIG_STDBYMODE_CLEAR		(3 << 4)
  #define OMAP4_UHH_SYSCONFIG_NOSTDBY			(1 << 4)
  #define OMAP4_UHH_SYSCONFIG_SOFTRESET			(1 << 0)
  
  #define OMAP4_P1_MODE_CLEAR				(3 << 16)
  #define OMAP4_P1_MODE_TLL				(1 << 16)
  #define OMAP4_P1_MODE_HSIC				(3 << 16)
  #define OMAP4_P2_MODE_CLEAR				(3 << 18)
  #define OMAP4_P2_MODE_TLL				(1 << 18)
  #define OMAP4_P2_MODE_HSIC				(3 << 18)

  #define	OMAP_UHH_DEBUG_CSR				(0x44)
  
  /* Values of UHH_REVISION - Note: these are not given in the TRM */
  #define OMAP_USBHS_REV1		0x00000010	/* OMAP3 */
  #define OMAP_USBHS_REV2		0x50700100	/* OMAP4 */
  
  #define is_omap_usbhs_rev1(x)	(x->usbhs_rev == OMAP_USBHS_REV1)
  #define is_omap_usbhs_rev2(x)	(x->usbhs_rev == OMAP_USBHS_REV2)
  
  #define is_ehci_phy_mode(x)	(x == OMAP_EHCI_PORT_MODE_PHY)
  #define is_ehci_tll_mode(x)	(x == OMAP_EHCI_PORT_MODE_TLL)
  #define is_ehci_hsic_mode(x)	(x == OMAP_EHCI_PORT_MODE_HSIC)
  
  
  struct usbhs_hcd_omap {

  	int				nports;

  	struct clk			**utmi_clk;

  	struct clk			**hsic60m_clk;
  	struct clk			**hsic480m_clk;

  	struct clk			*xclk60mhsp1_ck;
  	struct clk			*xclk60mhsp2_ck;

  	struct clk			*utmi_p1_gfclk;
  	struct clk			*utmi_p2_gfclk;

  	struct clk			*init_60m_fclk;

  	struct clk			*ehci_logic_fck;

  
  	void __iomem			*uhh_base;

  	struct usbhs_omap_platform_data	*pdata;

  
  	u32				usbhs_rev;

  };
  /*-------------------------------------------------------------------------*/

  static const char usbhs_driver_name[] = USBHS_DRIVER_NAME;

  static u64 usbhs_dmamask = DMA_BIT_MASK(32);

  
  /*-------------------------------------------------------------------------*/
  
  static inline void usbhs_write(void __iomem *base, u32 reg, u32 val)
  {

  	writel_relaxed(val, base + reg);

  }
  
  static inline u32 usbhs_read(void __iomem *base, u32 reg)
  {

  	return readl_relaxed(base + reg);

  }

  /*-------------------------------------------------------------------------*/

  /**
   * Map 'enum usbhs_omap_port_mode' found in <linux/platform_data/usb-omap.h>
   * to the device tree binding portN-mode found in
   * 'Documentation/devicetree/bindings/mfd/omap-usb-host.txt'
   */
  static const char * const port_modes[] = {
  	[OMAP_USBHS_PORT_MODE_UNUSED]	= "",
  	[OMAP_EHCI_PORT_MODE_PHY]	= "ehci-phy",
  	[OMAP_EHCI_PORT_MODE_TLL]	= "ehci-tll",
  	[OMAP_EHCI_PORT_MODE_HSIC]	= "ehci-hsic",
  	[OMAP_OHCI_PORT_MODE_PHY_6PIN_DATSE0]	= "ohci-phy-6pin-datse0",
  	[OMAP_OHCI_PORT_MODE_PHY_6PIN_DPDM]	= "ohci-phy-6pin-dpdm",
  	[OMAP_OHCI_PORT_MODE_PHY_3PIN_DATSE0]	= "ohci-phy-3pin-datse0",
  	[OMAP_OHCI_PORT_MODE_PHY_4PIN_DPDM]	= "ohci-phy-4pin-dpdm",
  	[OMAP_OHCI_PORT_MODE_TLL_6PIN_DATSE0]	= "ohci-tll-6pin-datse0",
  	[OMAP_OHCI_PORT_MODE_TLL_6PIN_DPDM]	= "ohci-tll-6pin-dpdm",
  	[OMAP_OHCI_PORT_MODE_TLL_3PIN_DATSE0]	= "ohci-tll-3pin-datse0",
  	[OMAP_OHCI_PORT_MODE_TLL_4PIN_DPDM]	= "ohci-tll-4pin-dpdm",
  	[OMAP_OHCI_PORT_MODE_TLL_2PIN_DATSE0]	= "ohci-tll-2pin-datse0",
  	[OMAP_OHCI_PORT_MODE_TLL_2PIN_DPDM]	= "ohci-tll-2pin-dpdm",
  };
  
  /**
   * omap_usbhs_get_dt_port_mode - Get the 'enum usbhs_omap_port_mode'
   * from the port mode string.
   * @mode: The port mode string, usually obtained from device tree.
   *
   * The function returns the 'enum usbhs_omap_port_mode' that matches the
   * provided port mode string as per the port_modes table.
   * If no match is found it returns -ENODEV
   */

  static int omap_usbhs_get_dt_port_mode(const char *mode)

  {
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(port_modes); i++) {
  		if (!strcmp(mode, port_modes[i]))
  			return i;
  	}
  
  	return -ENODEV;
  }

  static struct platform_device *omap_usbhs_alloc_child(const char *name,
  			struct resource	*res, int num_resources, void *pdata,
  			size_t pdata_size, struct device *dev)
  {
  	struct platform_device	*child;
  	int			ret;
  
  	child = platform_device_alloc(name, 0);
  
  	if (!child) {
  		dev_err(dev, "platform_device_alloc %s failed
  ", name);
  		goto err_end;
  	}
  
  	ret = platform_device_add_resources(child, res, num_resources);
  	if (ret) {
  		dev_err(dev, "platform_device_add_resources failed
  ");
  		goto err_alloc;
  	}
  
  	ret = platform_device_add_data(child, pdata, pdata_size);
  	if (ret) {
  		dev_err(dev, "platform_device_add_data failed
  ");
  		goto err_alloc;
  	}
  
  	child->dev.dma_mask		= &usbhs_dmamask;

  	dma_set_coherent_mask(&child->dev, DMA_BIT_MASK(32));

  	child->dev.parent		= dev;
  
  	ret = platform_device_add(child);
  	if (ret) {
  		dev_err(dev, "platform_device_add failed
  ");
  		goto err_alloc;
  	}
  
  	return child;
  
  err_alloc:
  	platform_device_put(child);
  
  err_end:
  	return NULL;
  }
  
  static int omap_usbhs_alloc_children(struct platform_device *pdev)
  {
  	struct device				*dev = &pdev->dev;

  	struct usbhs_omap_platform_data		*pdata = dev_get_platdata(dev);

  	struct platform_device			*ehci;
  	struct platform_device			*ohci;
  	struct resource				*res;
  	struct resource				resources[2];
  	int					ret;

  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ehci");
  	if (!res) {
  		dev_err(dev, "EHCI get resource IORESOURCE_MEM failed
  ");
  		ret = -ENODEV;
  		goto err_end;
  	}
  	resources[0] = *res;
  
  	res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ehci-irq");
  	if (!res) {
  		dev_err(dev, " EHCI get resource IORESOURCE_IRQ failed
  ");
  		ret = -ENODEV;
  		goto err_end;
  	}
  	resources[1] = *res;

  	ehci = omap_usbhs_alloc_child(OMAP_EHCI_DEVICE, resources, 2, pdata,
  		sizeof(*pdata), dev);

  
  	if (!ehci) {
  		dev_err(dev, "omap_usbhs_alloc_child failed
  ");

  		ret = -ENOMEM;

  		goto err_end;
  	}
  
  	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ohci");
  	if (!res) {
  		dev_err(dev, "OHCI get resource IORESOURCE_MEM failed
  ");
  		ret = -ENODEV;
  		goto err_ehci;
  	}
  	resources[0] = *res;
  
  	res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "ohci-irq");
  	if (!res) {
  		dev_err(dev, "OHCI get resource IORESOURCE_IRQ failed
  ");
  		ret = -ENODEV;
  		goto err_ehci;
  	}
  	resources[1] = *res;

  	ohci = omap_usbhs_alloc_child(OMAP_OHCI_DEVICE, resources, 2, pdata,
  		sizeof(*pdata), dev);

  	if (!ohci) {
  		dev_err(dev, "omap_usbhs_alloc_child failed
  ");

  		ret = -ENOMEM;

  		goto err_ehci;
  	}
  
  	return 0;
  
  err_ehci:

  	platform_device_unregister(ehci);

  
  err_end:
  	return ret;
  }

  static bool is_ohci_port(enum usbhs_omap_port_mode pmode)
  {
  	switch (pmode) {
  	case OMAP_OHCI_PORT_MODE_PHY_6PIN_DATSE0:
  	case OMAP_OHCI_PORT_MODE_PHY_6PIN_DPDM:
  	case OMAP_OHCI_PORT_MODE_PHY_3PIN_DATSE0:
  	case OMAP_OHCI_PORT_MODE_PHY_4PIN_DPDM:
  	case OMAP_OHCI_PORT_MODE_TLL_6PIN_DATSE0:
  	case OMAP_OHCI_PORT_MODE_TLL_6PIN_DPDM:
  	case OMAP_OHCI_PORT_MODE_TLL_3PIN_DATSE0:
  	case OMAP_OHCI_PORT_MODE_TLL_4PIN_DPDM:
  	case OMAP_OHCI_PORT_MODE_TLL_2PIN_DATSE0:
  	case OMAP_OHCI_PORT_MODE_TLL_2PIN_DPDM:
  		return true;
  
  	default:
  		return false;
  	}
  }

  static int usbhs_runtime_resume(struct device *dev)

  {
  	struct usbhs_hcd_omap		*omap = dev_get_drvdata(dev);

  	struct usbhs_omap_platform_data	*pdata = omap->pdata;

  	int i, r;

  
  	dev_dbg(dev, "usbhs_runtime_resume
  ");

  	omap_tll_enable(pdata);

  	if (!IS_ERR(omap->ehci_logic_fck))

  		clk_prepare_enable(omap->ehci_logic_fck);

  	for (i = 0; i < omap->nports; i++) {

  		switch (pdata->port_mode[i]) {
  		case OMAP_EHCI_PORT_MODE_HSIC:
  			if (!IS_ERR(omap->hsic60m_clk[i])) {

  				r = clk_prepare_enable(omap->hsic60m_clk[i]);

  				if (r) {
  					dev_err(dev,
  					 "Can't enable port %d hsic60m clk:%d
  ",
  					 i, r);
  				}
  			}
  
  			if (!IS_ERR(omap->hsic480m_clk[i])) {

  				r = clk_prepare_enable(omap->hsic480m_clk[i]);

  				if (r) {
  					dev_err(dev,
  					 "Can't enable port %d hsic480m clk:%d
  ",
  					 i, r);
  				}
  			}
  		/* Fall through as HSIC mode needs utmi_clk */
  
  		case OMAP_EHCI_PORT_MODE_TLL:
  			if (!IS_ERR(omap->utmi_clk[i])) {

  				r = clk_prepare_enable(omap->utmi_clk[i]);

  				if (r) {
  					dev_err(dev,
  					 "Can't enable port %d clk : %d
  ",
  					 i, r);
  				}
  			}
  			break;
  		default:
  			break;
  		}

  	}

  	return 0;
  }
  
  static int usbhs_runtime_suspend(struct device *dev)
  {
  	struct usbhs_hcd_omap		*omap = dev_get_drvdata(dev);

  	struct usbhs_omap_platform_data	*pdata = omap->pdata;

  	int i;

  
  	dev_dbg(dev, "usbhs_runtime_suspend
  ");

  	for (i = 0; i < omap->nports; i++) {

  		switch (pdata->port_mode[i]) {
  		case OMAP_EHCI_PORT_MODE_HSIC:
  			if (!IS_ERR(omap->hsic60m_clk[i]))

  				clk_disable_unprepare(omap->hsic60m_clk[i]);

  
  			if (!IS_ERR(omap->hsic480m_clk[i]))

  				clk_disable_unprepare(omap->hsic480m_clk[i]);

  		/* Fall through as utmi_clks were used in HSIC mode */
  
  		case OMAP_EHCI_PORT_MODE_TLL:
  			if (!IS_ERR(omap->utmi_clk[i]))

  				clk_disable_unprepare(omap->utmi_clk[i]);

  			break;
  		default:
  			break;
  		}

  	}

  	if (!IS_ERR(omap->ehci_logic_fck))

  		clk_disable_unprepare(omap->ehci_logic_fck);

  	omap_tll_disable(pdata);

  
  	return 0;
  }

  static unsigned omap_usbhs_rev1_hostconfig(struct usbhs_hcd_omap *omap,
  						unsigned reg)
  {
  	struct usbhs_omap_platform_data	*pdata = omap->pdata;
  	int i;
  
  	for (i = 0; i < omap->nports; i++) {
  		switch (pdata->port_mode[i]) {
  		case OMAP_USBHS_PORT_MODE_UNUSED:
  			reg &= ~(OMAP_UHH_HOSTCONFIG_P1_CONNECT_STATUS << i);
  			break;
  		case OMAP_EHCI_PORT_MODE_PHY:
  			if (pdata->single_ulpi_bypass)
  				break;
  
  			if (i == 0)
  				reg &= ~OMAP_UHH_HOSTCONFIG_ULPI_P1_BYPASS;
  			else
  				reg &= ~(OMAP_UHH_HOSTCONFIG_ULPI_P2_BYPASS
  								<< (i-1));
  			break;
  		default:
  			if (pdata->single_ulpi_bypass)
  				break;
  
  			if (i == 0)
  				reg |= OMAP_UHH_HOSTCONFIG_ULPI_P1_BYPASS;
  			else
  				reg |= OMAP_UHH_HOSTCONFIG_ULPI_P2_BYPASS
  								<< (i-1);
  			break;
  		}
  	}
  
  	if (pdata->single_ulpi_bypass) {
  		/* bypass ULPI only if none of the ports use PHY mode */
  		reg |= OMAP_UHH_HOSTCONFIG_ULPI_BYPASS;
  
  		for (i = 0; i < omap->nports; i++) {
  			if (is_ehci_phy_mode(pdata->port_mode[i])) {

  				reg &= ~OMAP_UHH_HOSTCONFIG_ULPI_BYPASS;

  				break;
  			}
  		}
  	}
  
  	return reg;
  }
  
  static unsigned omap_usbhs_rev2_hostconfig(struct usbhs_hcd_omap *omap,
  						unsigned reg)
  {
  	struct usbhs_omap_platform_data	*pdata = omap->pdata;
  	int i;
  
  	for (i = 0; i < omap->nports; i++) {
  		/* Clear port mode fields for PHY mode */
  		reg &= ~(OMAP4_P1_MODE_CLEAR << 2 * i);
  
  		if (is_ehci_tll_mode(pdata->port_mode[i]) ||
  				(is_ohci_port(pdata->port_mode[i])))
  			reg |= OMAP4_P1_MODE_TLL << 2 * i;
  		else if (is_ehci_hsic_mode(pdata->port_mode[i]))
  			reg |= OMAP4_P1_MODE_HSIC << 2 * i;
  	}
  
  	return reg;
  }

  static void omap_usbhs_init(struct device *dev)
  {
  	struct usbhs_hcd_omap		*omap = dev_get_drvdata(dev);

  	unsigned			reg;
  
  	dev_dbg(dev, "starting TI HSUSB Controller
  ");

  	pm_runtime_get_sync(dev);

  	reg = usbhs_read(omap->uhh_base, OMAP_UHH_HOSTCONFIG);
  	/* setup ULPI bypass and burst configurations */
  	reg |= (OMAP_UHH_HOSTCONFIG_INCR4_BURST_EN
  			| OMAP_UHH_HOSTCONFIG_INCR8_BURST_EN
  			| OMAP_UHH_HOSTCONFIG_INCR16_BURST_EN);
  	reg |= OMAP4_UHH_HOSTCONFIG_APP_START_CLK;
  	reg &= ~OMAP_UHH_HOSTCONFIG_INCRX_ALIGN_EN;

  	switch (omap->usbhs_rev) {
  	case OMAP_USBHS_REV1:

  		reg = omap_usbhs_rev1_hostconfig(omap, reg);

  		break;
  
  	case OMAP_USBHS_REV2:

  		reg = omap_usbhs_rev2_hostconfig(omap, reg);

  		break;
  
  	default:	/* newer revisions */

  		reg = omap_usbhs_rev2_hostconfig(omap, reg);

  		break;

  	}
  
  	usbhs_write(omap->uhh_base, OMAP_UHH_HOSTCONFIG, reg);
  	dev_dbg(dev, "UHH setup done, uhh_hostconfig=%x
  ", reg);

  	pm_runtime_put_sync(dev);

  }

  static int usbhs_omap_get_dt_pdata(struct device *dev,
  					struct usbhs_omap_platform_data *pdata)
  {
  	int ret, i;
  	struct device_node *node = dev->of_node;
  
  	ret = of_property_read_u32(node, "num-ports", &pdata->nports);
  	if (ret)
  		pdata->nports = 0;
  
  	if (pdata->nports > OMAP3_HS_USB_PORTS) {
  		dev_warn(dev, "Too many num_ports <%d> in device tree. Max %d
  ",
  				pdata->nports, OMAP3_HS_USB_PORTS);
  		return -ENODEV;
  	}
  
  	/* get port modes */
  	for (i = 0; i < OMAP3_HS_USB_PORTS; i++) {
  		char prop[11];
  		const char *mode;
  
  		pdata->port_mode[i] = OMAP_USBHS_PORT_MODE_UNUSED;
  
  		snprintf(prop, sizeof(prop), "port%d-mode", i + 1);
  		ret = of_property_read_string(node, prop, &mode);
  		if (ret < 0)
  			continue;
  
  		ret = omap_usbhs_get_dt_port_mode(mode);
  		if (ret < 0) {
  			dev_warn(dev, "Invalid port%d-mode \"%s\" in device tree
  ",
  					i, mode);
  			return -ENODEV;
  		}
  
  		dev_dbg(dev, "port%d-mode: %s -> %d
  ", i, mode, ret);
  		pdata->port_mode[i] = ret;
  	}
  
  	/* get flags */
  	pdata->single_ulpi_bypass = of_property_read_bool(node,
  						"single-ulpi-bypass");
  
  	return 0;
  }

  static const struct of_device_id usbhs_child_match_table[] = {

  	{ .compatible = "ti,omap-ehci", },
  	{ .compatible = "ti,omap-ohci", },
  	{ }
  };

  /**
   * usbhs_omap_probe - initialize TI-based HCDs
   *
   * Allocates basic resources for this USB host controller.
   */

  static int usbhs_omap_probe(struct platform_device *pdev)

  {

  	struct device			*dev =  &pdev->dev;

  	struct usbhs_omap_platform_data	*pdata = dev_get_platdata(dev);

  	struct usbhs_hcd_omap		*omap;
  	struct resource			*res;
  	int				ret = 0;
  	int				i;

  	bool				need_logic_fck;

  	if (dev->of_node) {
  		/* For DT boot we populate platform data from OF node */
  		pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
  		if (!pdata)
  			return -ENOMEM;
  
  		ret = usbhs_omap_get_dt_pdata(dev, pdata);
  		if (ret)
  			return ret;
  
  		dev->platform_data = pdata;
  	}

  	if (!pdata) {
  		dev_err(dev, "Missing platform data
  ");

  		return -ENODEV;

  	}

  	if (pdata->nports > OMAP3_HS_USB_PORTS) {
  		dev_info(dev, "Too many num_ports <%d> in platform_data. Max %d
  ",
  				pdata->nports, OMAP3_HS_USB_PORTS);
  		return -ENODEV;
  	}

  	omap = devm_kzalloc(dev, sizeof(*omap), GFP_KERNEL);

  	if (!omap) {
  		dev_err(dev, "Memory allocation failed
  ");

  		return -ENOMEM;
  	}

  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

  	omap->uhh_base = devm_ioremap_resource(dev, res);
  	if (IS_ERR(omap->uhh_base))
  		return PTR_ERR(omap->uhh_base);

  	omap->pdata = pdata;

  	/* Initialize the TLL subsystem */
  	omap_tll_init(pdata);

  	pm_runtime_enable(dev);

  	platform_set_drvdata(pdev, omap);
  	pm_runtime_get_sync(dev);
  
  	omap->usbhs_rev = usbhs_read(omap->uhh_base, OMAP_UHH_REVISION);
  
  	/* we need to call runtime suspend before we update omap->nports
  	 * to prevent unbalanced clk_disable()
  	 */
  	pm_runtime_put_sync(dev);

  	/*
  	 * If platform data contains nports then use that
  	 * else make out number of ports from USBHS revision
  	 */
  	if (pdata->nports) {
  		omap->nports = pdata->nports;
  	} else {
  		switch (omap->usbhs_rev) {
  		case OMAP_USBHS_REV1:
  			omap->nports = 3;
  			break;
  		case OMAP_USBHS_REV2:
  			omap->nports = 2;
  			break;
  		default:
  			omap->nports = OMAP3_HS_USB_PORTS;
  			dev_dbg(dev,

  			 "USB HOST Rev:0x%x not recognized, assuming %d ports
  ",

  			 omap->usbhs_rev, omap->nports);
  			break;
  		}

  		pdata->nports = omap->nports;

  	}

  	i = sizeof(struct clk *) * omap->nports;
  	omap->utmi_clk = devm_kzalloc(dev, i, GFP_KERNEL);

  	omap->hsic480m_clk = devm_kzalloc(dev, i, GFP_KERNEL);
  	omap->hsic60m_clk = devm_kzalloc(dev, i, GFP_KERNEL);
  
  	if (!omap->utmi_clk || !omap->hsic480m_clk || !omap->hsic60m_clk) {

  		dev_err(dev, "Memory allocation failed
  ");
  		ret = -ENOMEM;
  		goto err_mem;
  	}

  	/* Set all clocks as invalid to begin with */
  	omap->ehci_logic_fck = ERR_PTR(-ENODEV);
  	omap->init_60m_fclk = ERR_PTR(-ENODEV);
  	omap->utmi_p1_gfclk = ERR_PTR(-ENODEV);
  	omap->utmi_p2_gfclk = ERR_PTR(-ENODEV);
  	omap->xclk60mhsp1_ck = ERR_PTR(-ENODEV);
  	omap->xclk60mhsp2_ck = ERR_PTR(-ENODEV);

  	for (i = 0; i < omap->nports; i++) {

  		omap->utmi_clk[i] = ERR_PTR(-ENODEV);
  		omap->hsic480m_clk[i] = ERR_PTR(-ENODEV);
  		omap->hsic60m_clk[i] = ERR_PTR(-ENODEV);

  	}

  	/* for OMAP3 i.e. USBHS REV1 */
  	if (omap->usbhs_rev == OMAP_USBHS_REV1) {
  		need_logic_fck = false;
  		for (i = 0; i < omap->nports; i++) {
  			if (is_ehci_phy_mode(pdata->port_mode[i]) ||
  			    is_ehci_tll_mode(pdata->port_mode[i]) ||
  			    is_ehci_hsic_mode(pdata->port_mode[i]))
  
  				need_logic_fck |= true;
  		}
  
  		if (need_logic_fck) {
  			omap->ehci_logic_fck = devm_clk_get(dev,

  							    "usbhost_120m_fck");

  			if (IS_ERR(omap->ehci_logic_fck)) {
  				ret = PTR_ERR(omap->ehci_logic_fck);

  				dev_err(dev, "usbhost_120m_fck failed:%d
  ",
  					ret);

  				goto err_mem;

  			}

  		}

  		goto initialize;

  	}

  	/* for OMAP4+ i.e. USBHS REV2+ */

  	omap->utmi_p1_gfclk = devm_clk_get(dev, "utmi_p1_gfclk");

  	if (IS_ERR(omap->utmi_p1_gfclk)) {
  		ret = PTR_ERR(omap->utmi_p1_gfclk);
  		dev_err(dev, "utmi_p1_gfclk failed error:%d
  ", ret);

  		goto err_mem;

  	}

  	omap->utmi_p2_gfclk = devm_clk_get(dev, "utmi_p2_gfclk");

  	if (IS_ERR(omap->utmi_p2_gfclk)) {
  		ret = PTR_ERR(omap->utmi_p2_gfclk);
  		dev_err(dev, "utmi_p2_gfclk failed error:%d
  ", ret);

  		goto err_mem;

  	}

  	omap->xclk60mhsp1_ck = devm_clk_get(dev, "refclk_60m_ext_p1");

  	if (IS_ERR(omap->xclk60mhsp1_ck)) {
  		ret = PTR_ERR(omap->xclk60mhsp1_ck);

  		dev_err(dev, "refclk_60m_ext_p1 failed error:%d
  ", ret);

  		goto err_mem;

  	}

  	omap->xclk60mhsp2_ck = devm_clk_get(dev, "refclk_60m_ext_p2");

  	if (IS_ERR(omap->xclk60mhsp2_ck)) {
  		ret = PTR_ERR(omap->xclk60mhsp2_ck);

  		dev_err(dev, "refclk_60m_ext_p2 failed error:%d
  ", ret);

  		goto err_mem;

  	}

  	omap->init_60m_fclk = devm_clk_get(dev, "refclk_60m_int");

  	if (IS_ERR(omap->init_60m_fclk)) {
  		ret = PTR_ERR(omap->init_60m_fclk);

  		dev_err(dev, "refclk_60m_int failed error:%d
  ", ret);

  		goto err_mem;

  	}
  
  	for (i = 0; i < omap->nports; i++) {

  		char clkname[30];

  
  		/* clock names are indexed from 1*/
  		snprintf(clkname, sizeof(clkname),
  				"usb_host_hs_utmi_p%d_clk", i + 1);
  
  		/* If a clock is not found we won't bail out as not all
  		 * platforms have all clocks and we can function without
  		 * them
  		 */

  		omap->utmi_clk[i] = devm_clk_get(dev, clkname);

  		if (IS_ERR(omap->utmi_clk[i])) {
  			ret = PTR_ERR(omap->utmi_clk[i]);
  			dev_err(dev, "Failed to get clock : %s : %d
  ",
  				clkname, ret);
  			goto err_mem;
  		}

  
  		snprintf(clkname, sizeof(clkname),
  				"usb_host_hs_hsic480m_p%d_clk", i + 1);

  		omap->hsic480m_clk[i] = devm_clk_get(dev, clkname);

  		if (IS_ERR(omap->hsic480m_clk[i])) {
  			ret = PTR_ERR(omap->hsic480m_clk[i]);
  			dev_err(dev, "Failed to get clock : %s : %d
  ",
  				clkname, ret);
  			goto err_mem;
  		}

  
  		snprintf(clkname, sizeof(clkname),
  				"usb_host_hs_hsic60m_p%d_clk", i + 1);

  		omap->hsic60m_clk[i] = devm_clk_get(dev, clkname);

  		if (IS_ERR(omap->hsic60m_clk[i])) {
  			ret = PTR_ERR(omap->hsic60m_clk[i]);
  			dev_err(dev, "Failed to get clock : %s : %d
  ",
  				clkname, ret);
  			goto err_mem;
  		}

  	}

  	if (is_ehci_phy_mode(pdata->port_mode[0])) {

  		ret = clk_set_parent(omap->utmi_p1_gfclk,

  					omap->xclk60mhsp1_ck);

  		if (ret != 0) {
  			dev_err(dev, "xclk60mhsp1_ck set parent failed: %d
  ",
  				ret);
  			goto err_mem;
  		}

  	} else if (is_ehci_tll_mode(pdata->port_mode[0])) {

  		ret = clk_set_parent(omap->utmi_p1_gfclk,

  					omap->init_60m_fclk);

  		if (ret != 0) {
  			dev_err(dev, "P0 init_60m_fclk set parent failed: %d
  ",
  				ret);
  			goto err_mem;
  		}

  	}

  	if (is_ehci_phy_mode(pdata->port_mode[1])) {

  		ret = clk_set_parent(omap->utmi_p2_gfclk,

  					omap->xclk60mhsp2_ck);

  		if (ret != 0) {
  			dev_err(dev, "xclk60mhsp2_ck set parent failed: %d
  ",
  				ret);
  			goto err_mem;
  		}

  	} else if (is_ehci_tll_mode(pdata->port_mode[1])) {

  		ret = clk_set_parent(omap->utmi_p2_gfclk,

  						omap->init_60m_fclk);

  		if (ret != 0) {
  			dev_err(dev, "P1 init_60m_fclk set parent failed: %d
  ",
  				ret);
  			goto err_mem;
  		}

  	}

  initialize:

  	omap_usbhs_init(dev);

  
  	if (dev->of_node) {
  		ret = of_platform_populate(dev->of_node,
  				usbhs_child_match_table, NULL, dev);
  
  		if (ret) {
  			dev_err(dev, "Failed to create DT children: %d
  ", ret);

  			goto err_mem;

  		}
  
  	} else {
  		ret = omap_usbhs_alloc_children(pdev);
  		if (ret) {
  			dev_err(dev, "omap_usbhs_alloc_children failed: %d
  ",
  						ret);

  			goto err_mem;

  		}

  	}

  	return 0;

  err_mem:

  	pm_runtime_disable(dev);

  	return ret;

  }

  static int usbhs_omap_remove_child(struct device *dev, void *data)
  {
  	dev_info(dev, "unregistering
  ");
  	platform_device_unregister(to_platform_device(dev));
  	return 0;
  }

  /**
   * usbhs_omap_remove - shutdown processing for UHH & TLL HCDs
   * @pdev: USB Host Controller being removed
   *
   * Reverses the effect of usbhs_omap_probe().
   */

  static int usbhs_omap_remove(struct platform_device *pdev)

  {

  	pm_runtime_disable(&pdev->dev);

  	/* remove children */
  	device_for_each_child(&pdev->dev, NULL, usbhs_omap_remove_child);

  	return 0;

  }

  
  static const struct dev_pm_ops usbhsomap_dev_pm_ops = {
  	.runtime_suspend	= usbhs_runtime_suspend,
  	.runtime_resume		= usbhs_runtime_resume,
  };

  static const struct of_device_id usbhs_omap_dt_ids[] = {
  	{ .compatible = "ti,usbhs-host" },
  	{ }
  };
  
  MODULE_DEVICE_TABLE(of, usbhs_omap_dt_ids);

  static struct platform_driver usbhs_omap_driver = {
  	.driver = {
  		.name		= (char *)usbhs_driver_name,

  		.pm		= &usbhsomap_dev_pm_ops,

  		.of_match_table = usbhs_omap_dt_ids,

  	},

  	.remove		= usbhs_omap_remove,

  };
  
  MODULE_AUTHOR("Keshava Munegowda <keshava_mgowda@ti.com>");

  MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");

  MODULE_ALIAS("platform:" USBHS_DRIVER_NAME);
  MODULE_LICENSE("GPL v2");
  MODULE_DESCRIPTION("usb host common core driver for omap EHCI and OHCI");
  
  static int __init omap_usbhs_drvinit(void)
  {
  	return platform_driver_probe(&usbhs_omap_driver, usbhs_omap_probe);
  }
  
  /*
   * init before ehci and ohci drivers;
   * The usbhs core driver should be initialized much before
   * the omap ehci and ohci probe functions are called.

   * This usbhs core driver should be initialized after
   * usb tll driver

   */

  fs_initcall_sync(omap_usbhs_drvinit);

  
  static void __exit omap_usbhs_drvexit(void)
  {
  	platform_driver_unregister(&usbhs_omap_driver);
  }
  module_exit(omap_usbhs_drvexit);