USB: ehci_omap: fix device detect issue with modules

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / usb / host / ehci-omap.c

/*
 * ehci-omap.c - driver for USBHOST on OMAP 34xx processor
 *
 * Bus Glue for OMAP34xx USBHOST 3 port EHCI controller
 * Tested on OMAP3430 ES2.0 SDP
 *
 * Copyright (C) 2007-2008 Texas Instruments, Inc.
 *      Author: Vikram Pandita <vikram.pandita@ti.com>
 *
 * Copyright (C) 2009 Nokia Corporation
 *      Contact: Felipe Balbi <felipe.balbi@nokia.com>
 *
 * Based on "ehci-fsl.c" and "ehci-au1xxx.c" ehci glue layers
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 * TODO (last updated Feb 12, 2010):
 *      - add kernel-doc
 *      - enable AUTOIDLE
 *      - add suspend/resume
 *      - move workarounds to board-files
 */

#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/gpio.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/usb/ulpi.h>
#include <plat/usb.h>

/*
 * OMAP USBHOST Register addresses: VIRTUAL ADDRESSES
 *      Use ehci_omap_readl()/ehci_omap_writel() functions
 */

/* TLL Register Set */
#define OMAP_USBTLL_REVISION                            (0x00)
#define OMAP_USBTLL_SYSCONFIG                           (0x10)
#define OMAP_USBTLL_SYSCONFIG_CACTIVITY                 (1 << 8)
#define OMAP_USBTLL_SYSCONFIG_SIDLEMODE                 (1 << 3)
#define OMAP_USBTLL_SYSCONFIG_ENAWAKEUP                 (1 << 2)
#define OMAP_USBTLL_SYSCONFIG_SOFTRESET                 (1 << 1)
#define OMAP_USBTLL_SYSCONFIG_AUTOIDLE                  (1 << 0)

#define OMAP_USBTLL_SYSSTATUS                           (0x14)
#define OMAP_USBTLL_SYSSTATUS_RESETDONE                 (1 << 0)

#define OMAP_USBTLL_IRQSTATUS                           (0x18)
#define OMAP_USBTLL_IRQENABLE                           (0x1C)

#define OMAP_TLL_SHARED_CONF                            (0x30)
#define OMAP_TLL_SHARED_CONF_USB_90D_DDR_EN             (1 << 6)
#define OMAP_TLL_SHARED_CONF_USB_180D_SDR_EN            (1 << 5)
#define OMAP_TLL_SHARED_CONF_USB_DIVRATION              (1 << 2)
#define OMAP_TLL_SHARED_CONF_FCLK_REQ                   (1 << 1)
#define OMAP_TLL_SHARED_CONF_FCLK_IS_ON                 (1 << 0)

#define OMAP_TLL_CHANNEL_CONF(num)                      (0x040 + 0x004 * num)
#define OMAP_TLL_CHANNEL_CONF_ULPINOBITSTUFF            (1 << 11)
#define OMAP_TLL_CHANNEL_CONF_ULPI_ULPIAUTOIDLE         (1 << 10)
#define OMAP_TLL_CHANNEL_CONF_UTMIAUTOIDLE              (1 << 9)
#define OMAP_TLL_CHANNEL_CONF_ULPIDDRMODE               (1 << 8)
#define OMAP_TLL_CHANNEL_CONF_CHANEN                    (1 << 0)

#define OMAP_TLL_ULPI_FUNCTION_CTRL(num)                (0x804 + 0x100 * num)
#define OMAP_TLL_ULPI_INTERFACE_CTRL(num)               (0x807 + 0x100 * num)
#define OMAP_TLL_ULPI_OTG_CTRL(num)                     (0x80A + 0x100 * num)
#define OMAP_TLL_ULPI_INT_EN_RISE(num)                  (0x80D + 0x100 * num)
#define OMAP_TLL_ULPI_INT_EN_FALL(num)                  (0x810 + 0x100 * num)
#define OMAP_TLL_ULPI_INT_STATUS(num)                   (0x813 + 0x100 * num)
#define OMAP_TLL_ULPI_INT_LATCH(num)                    (0x814 + 0x100 * num)
#define OMAP_TLL_ULPI_DEBUG(num)                        (0x815 + 0x100 * num)
#define OMAP_TLL_ULPI_SCRATCH_REGISTER(num)             (0x816 + 0x100 * num)

#define OMAP_TLL_CHANNEL_COUNT                          3
#define OMAP_TLL_CHANNEL_1_EN_MASK                      (1 << 1)
#define OMAP_TLL_CHANNEL_2_EN_MASK                      (1 << 2)
#define OMAP_TLL_CHANNEL_3_EN_MASK                      (1 << 4)

/* 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 OMAP_UHH_DEBUG_CSR                              (0x44)

/* EHCI Register Set */
#define EHCI_INSNREG04                                  (0xA0)
#define EHCI_INSNREG04_DISABLE_UNSUSPEND                (1 << 5)
#define EHCI_INSNREG05_ULPI                             (0xA4)
#define EHCI_INSNREG05_ULPI_CONTROL_SHIFT               31
#define EHCI_INSNREG05_ULPI_PORTSEL_SHIFT               24
#define EHCI_INSNREG05_ULPI_OPSEL_SHIFT                 22
#define EHCI_INSNREG05_ULPI_REGADD_SHIFT                16
#define EHCI_INSNREG05_ULPI_EXTREGADD_SHIFT             8
#define EHCI_INSNREG05_ULPI_WRDATA_SHIFT                0

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

static inline void ehci_omap_writel(void __iomem *base, u32 reg, u32 val)
{
        __raw_writel(val, base + reg);
}

static inline u32 ehci_omap_readl(void __iomem *base, u32 reg)
{
        return __raw_readl(base + reg);
}

static inline void ehci_omap_writeb(void __iomem *base, u8 reg, u8 val)
{
        __raw_writeb(val, base + reg);
}

static inline u8 ehci_omap_readb(void __iomem *base, u8 reg)
{
        return __raw_readb(base + reg);
}

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

struct ehci_hcd_omap {
        struct ehci_hcd         *ehci;
        struct device           *dev;

        struct clk              *usbhost_ick;
        struct clk              *usbhost2_120m_fck;
        struct clk              *usbhost1_48m_fck;
        struct clk              *usbtll_fck;
        struct clk              *usbtll_ick;

        /* FIXME the following two workarounds are
         * board specific not silicon-specific so these
         * should be moved to board-file instead.
         *
         * Maybe someone from TI will know better which
         * board is affected and needs the workarounds
         * to be applied
         */

        /* gpio for resetting phy */
        int                     reset_gpio_port[OMAP3_HS_USB_PORTS];

        /* phy reset workaround */
        int                     phy_reset;

        /* desired phy_mode: TLL, PHY */
        enum ehci_hcd_omap_mode port_mode[OMAP3_HS_USB_PORTS];

        void __iomem            *uhh_base;
        void __iomem            *tll_base;
        void __iomem            *ehci_base;

        /* Regulators for USB PHYs.
         * Each PHY can have a separate regulator.
         */
        struct regulator        *regulator[OMAP3_HS_USB_PORTS];
};

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

static void omap_usb_utmi_init(struct ehci_hcd_omap *omap, u8 tll_channel_mask)
{
        unsigned reg;
        int i;

        /* Program the 3 TLL channels upfront */
        for (i = 0; i < OMAP_TLL_CHANNEL_COUNT; i++) {
                reg = ehci_omap_readl(omap->tll_base, OMAP_TLL_CHANNEL_CONF(i));

                /* Disable AutoIdle, BitStuffing and use SDR Mode */
                reg &= ~(OMAP_TLL_CHANNEL_CONF_UTMIAUTOIDLE
                                | OMAP_TLL_CHANNEL_CONF_ULPINOBITSTUFF
                                | OMAP_TLL_CHANNEL_CONF_ULPIDDRMODE);
                ehci_omap_writel(omap->tll_base, OMAP_TLL_CHANNEL_CONF(i), reg);
        }

        /* Program Common TLL register */
        reg = ehci_omap_readl(omap->tll_base, OMAP_TLL_SHARED_CONF);
        reg |= (OMAP_TLL_SHARED_CONF_FCLK_IS_ON
                        | OMAP_TLL_SHARED_CONF_USB_DIVRATION
                        | OMAP_TLL_SHARED_CONF_USB_180D_SDR_EN);
        reg &= ~OMAP_TLL_SHARED_CONF_USB_90D_DDR_EN;

        ehci_omap_writel(omap->tll_base, OMAP_TLL_SHARED_CONF, reg);

        /* Enable channels now */
        for (i = 0; i < OMAP_TLL_CHANNEL_COUNT; i++) {
                reg = ehci_omap_readl(omap->tll_base, OMAP_TLL_CHANNEL_CONF(i));

                /* Enable only the reg that is needed */
                if (!(tll_channel_mask & 1<<i))
                        continue;

                reg |= OMAP_TLL_CHANNEL_CONF_CHANEN;
                ehci_omap_writel(omap->tll_base, OMAP_TLL_CHANNEL_CONF(i), reg);

                ehci_omap_writeb(omap->tll_base,
                                OMAP_TLL_ULPI_SCRATCH_REGISTER(i), 0xbe);
                dev_dbg(omap->dev, "ULPI_SCRATCH_REG[ch=%d]= 0x%02x\n",
                                i+1, ehci_omap_readb(omap->tll_base,
                                OMAP_TLL_ULPI_SCRATCH_REGISTER(i)));
        }
}

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

static void omap_ehci_soft_phy_reset(struct ehci_hcd_omap *omap, u8 port)
{
        unsigned long timeout = jiffies + msecs_to_jiffies(1000);
        unsigned reg = 0;

        reg = ULPI_FUNC_CTRL_RESET
                /* FUNCTION_CTRL_SET register */
                | (ULPI_SET(ULPI_FUNC_CTRL) << EHCI_INSNREG05_ULPI_REGADD_SHIFT)
                /* Write */
                | (2 << EHCI_INSNREG05_ULPI_OPSEL_SHIFT)
                /* PORTn */
                | ((port + 1) << EHCI_INSNREG05_ULPI_PORTSEL_SHIFT)
                /* start ULPI access*/
                | (1 << EHCI_INSNREG05_ULPI_CONTROL_SHIFT);

        ehci_omap_writel(omap->ehci_base, EHCI_INSNREG05_ULPI, reg);

        /* Wait for ULPI access completion */
        while ((ehci_omap_readl(omap->ehci_base, EHCI_INSNREG05_ULPI)
                        & (1 << EHCI_INSNREG05_ULPI_CONTROL_SHIFT))) {
                cpu_relax();

                if (time_after(jiffies, timeout)) {
                        dev_dbg(omap->dev, "phy reset operation timed out\n");
                        break;
                }
        }
}

/* omap_start_ehc
 *      - Start the TI USBHOST controller
 */
static int omap_start_ehc(struct ehci_hcd_omap *omap, struct usb_hcd *hcd)
{
        unsigned long timeout = jiffies + msecs_to_jiffies(1000);
        u8 tll_ch_mask = 0;
        unsigned reg = 0;
        int ret = 0;

        dev_dbg(omap->dev, "starting TI EHCI USB Controller\n");

        /* Enable Clocks for USBHOST */
        omap->usbhost_ick = clk_get(omap->dev, "usbhost_ick");
        if (IS_ERR(omap->usbhost_ick)) {
                ret =  PTR_ERR(omap->usbhost_ick);
                goto err_host_ick;
        }
        clk_enable(omap->usbhost_ick);

        omap->usbhost2_120m_fck = clk_get(omap->dev, "usbhost_120m_fck");
        if (IS_ERR(omap->usbhost2_120m_fck)) {
                ret = PTR_ERR(omap->usbhost2_120m_fck);
                goto err_host_120m_fck;
        }
        clk_enable(omap->usbhost2_120m_fck);

        omap->usbhost1_48m_fck = clk_get(omap->dev, "usbhost_48m_fck");
        if (IS_ERR(omap->usbhost1_48m_fck)) {
                ret = PTR_ERR(omap->usbhost1_48m_fck);
                goto err_host_48m_fck;
        }
        clk_enable(omap->usbhost1_48m_fck);

        if (omap->phy_reset) {
                /* Refer: ISSUE1 */
                if (gpio_is_valid(omap->reset_gpio_port[0])) {
                        gpio_request(omap->reset_gpio_port[0],
                                                "USB1 PHY reset");
                        gpio_direction_output(omap->reset_gpio_port[0], 0);
                }

                if (gpio_is_valid(omap->reset_gpio_port[1])) {
                        gpio_request(omap->reset_gpio_port[1],
                                                "USB2 PHY reset");
                        gpio_direction_output(omap->reset_gpio_port[1], 0);
                }

                /* Hold the PHY in RESET for enough time till DIR is high */
                udelay(10);
        }

        /* Configure TLL for 60Mhz clk for ULPI */
        omap->usbtll_fck = clk_get(omap->dev, "usbtll_fck");
        if (IS_ERR(omap->usbtll_fck)) {
                ret = PTR_ERR(omap->usbtll_fck);
                goto err_tll_fck;
        }
        clk_enable(omap->usbtll_fck);

        omap->usbtll_ick = clk_get(omap->dev, "usbtll_ick");
        if (IS_ERR(omap->usbtll_ick)) {
                ret = PTR_ERR(omap->usbtll_ick);
                goto err_tll_ick;
        }
        clk_enable(omap->usbtll_ick);

        /* perform TLL soft reset, and wait until reset is complete */
        ehci_omap_writel(omap->tll_base, OMAP_USBTLL_SYSCONFIG,
                        OMAP_USBTLL_SYSCONFIG_SOFTRESET);

        /* Wait for TLL reset to complete */
        while (!(ehci_omap_readl(omap->tll_base, OMAP_USBTLL_SYSSTATUS)
                        & OMAP_USBTLL_SYSSTATUS_RESETDONE)) {
                cpu_relax();

                if (time_after(jiffies, timeout)) {
                        dev_dbg(omap->dev, "operation timed out\n");
                        ret = -EINVAL;
                        goto err_sys_status;
                }
        }

        dev_dbg(omap->dev, "TLL RESET DONE\n");

        /* (1<<3) = no idle mode only for initial debugging */
        ehci_omap_writel(omap->tll_base, OMAP_USBTLL_SYSCONFIG,
                        OMAP_USBTLL_SYSCONFIG_ENAWAKEUP |
                        OMAP_USBTLL_SYSCONFIG_SIDLEMODE |
                        OMAP_USBTLL_SYSCONFIG_CACTIVITY);


        /* Put UHH in NoIdle/NoStandby mode */
        reg = ehci_omap_readl(omap->uhh_base, OMAP_UHH_SYSCONFIG);
        reg |= (OMAP_UHH_SYSCONFIG_ENAWAKEUP
                        | OMAP_UHH_SYSCONFIG_SIDLEMODE
                        | OMAP_UHH_SYSCONFIG_CACTIVITY
                        | OMAP_UHH_SYSCONFIG_MIDLEMODE);
        reg &= ~OMAP_UHH_SYSCONFIG_AUTOIDLE;

        ehci_omap_writel(omap->uhh_base, OMAP_UHH_SYSCONFIG, reg);

        reg = ehci_omap_readl(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 &= ~OMAP_UHH_HOSTCONFIG_INCRX_ALIGN_EN;

        if (omap->port_mode[0] == EHCI_HCD_OMAP_MODE_UNKNOWN)
                reg &= ~OMAP_UHH_HOSTCONFIG_P1_CONNECT_STATUS;
        if (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_UNKNOWN)
                reg &= ~OMAP_UHH_HOSTCONFIG_P2_CONNECT_STATUS;
        if (omap->port_mode[2] == EHCI_HCD_OMAP_MODE_UNKNOWN)
                reg &= ~OMAP_UHH_HOSTCONFIG_P3_CONNECT_STATUS;

        /* Bypass the TLL module for PHY mode operation */
        if (cpu_is_omap3430() && (omap_rev() <= OMAP3430_REV_ES2_1)) {
                dev_dbg(omap->dev, "OMAP3 ES version <= ES2.1\n");
                if ((omap->port_mode[0] == EHCI_HCD_OMAP_MODE_PHY) ||
                        (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_PHY) ||
                                (omap->port_mode[2] == EHCI_HCD_OMAP_MODE_PHY))
                        reg &= ~OMAP_UHH_HOSTCONFIG_ULPI_BYPASS;
                else
                        reg |= OMAP_UHH_HOSTCONFIG_ULPI_BYPASS;
        } else {
                dev_dbg(omap->dev, "OMAP3 ES version > ES2.1\n");
                if (omap->port_mode[0] == EHCI_HCD_OMAP_MODE_PHY)
                        reg &= ~OMAP_UHH_HOSTCONFIG_ULPI_P1_BYPASS;
                else if (omap->port_mode[0] == EHCI_HCD_OMAP_MODE_TLL)
                        reg |= OMAP_UHH_HOSTCONFIG_ULPI_P1_BYPASS;

                if (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_PHY)
                        reg &= ~OMAP_UHH_HOSTCONFIG_ULPI_P2_BYPASS;
                else if (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_TLL)
                        reg |= OMAP_UHH_HOSTCONFIG_ULPI_P2_BYPASS;

                if (omap->port_mode[2] == EHCI_HCD_OMAP_MODE_PHY)
                        reg &= ~OMAP_UHH_HOSTCONFIG_ULPI_P3_BYPASS;
                else if (omap->port_mode[2] == EHCI_HCD_OMAP_MODE_TLL)
                        reg |= OMAP_UHH_HOSTCONFIG_ULPI_P3_BYPASS;

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


        /*
         * An undocumented "feature" in the OMAP3 EHCI controller,
         * causes suspended ports to be taken out of suspend when
         * the USBCMD.Run/Stop bit is cleared (for example when
         * we do ehci_bus_suspend).
         * This breaks suspend-resume if the root-hub is allowed
         * to suspend. Writing 1 to this undocumented register bit
         * disables this feature and restores normal behavior.
         */
        ehci_omap_writel(omap->ehci_base, EHCI_INSNREG04,
                                EHCI_INSNREG04_DISABLE_UNSUSPEND);

        if ((omap->port_mode[0] == EHCI_HCD_OMAP_MODE_TLL) ||
                (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_TLL) ||
                        (omap->port_mode[2] == EHCI_HCD_OMAP_MODE_TLL)) {

                if (omap->port_mode[0] == EHCI_HCD_OMAP_MODE_TLL)
                        tll_ch_mask |= OMAP_TLL_CHANNEL_1_EN_MASK;
                if (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_TLL)
                        tll_ch_mask |= OMAP_TLL_CHANNEL_2_EN_MASK;
                if (omap->port_mode[2] == EHCI_HCD_OMAP_MODE_TLL)
                        tll_ch_mask |= OMAP_TLL_CHANNEL_3_EN_MASK;

                /* Enable UTMI mode for required TLL channels */
                omap_usb_utmi_init(omap, tll_ch_mask);
        }

        if (omap->phy_reset) {
                /* Refer ISSUE1:
                 * Hold the PHY in RESET for enough time till
                 * PHY is settled and ready
                 */
                udelay(10);

                if (gpio_is_valid(omap->reset_gpio_port[0]))
                        gpio_set_value(omap->reset_gpio_port[0], 1);

                if (gpio_is_valid(omap->reset_gpio_port[1]))
                        gpio_set_value(omap->reset_gpio_port[1], 1);
        }

        /* Soft reset the PHY using PHY reset command over ULPI */
        if (omap->port_mode[0] == EHCI_HCD_OMAP_MODE_PHY)
                omap_ehci_soft_phy_reset(omap, 0);
        if (omap->port_mode[1] == EHCI_HCD_OMAP_MODE_PHY)
                omap_ehci_soft_phy_reset(omap, 1);

        return 0;

err_sys_status:
        clk_disable(omap->usbtll_ick);
        clk_put(omap->usbtll_ick);

err_tll_ick:
        clk_disable(omap->usbtll_fck);
        clk_put(omap->usbtll_fck);

err_tll_fck:
        clk_disable(omap->usbhost1_48m_fck);
        clk_put(omap->usbhost1_48m_fck);

        if (omap->phy_reset) {
                if (gpio_is_valid(omap->reset_gpio_port[0]))
                        gpio_free(omap->reset_gpio_port[0]);

                if (gpio_is_valid(omap->reset_gpio_port[1]))
                        gpio_free(omap->reset_gpio_port[1]);
        }

err_host_48m_fck:
        clk_disable(omap->usbhost2_120m_fck);
        clk_put(omap->usbhost2_120m_fck);

err_host_120m_fck:
        clk_disable(omap->usbhost_ick);
        clk_put(omap->usbhost_ick);

err_host_ick:
        return ret;
}

static void omap_stop_ehc(struct ehci_hcd_omap *omap, struct usb_hcd *hcd)
{
        unsigned long timeout = jiffies + msecs_to_jiffies(100);

        dev_dbg(omap->dev, "stopping TI EHCI USB Controller\n");

        /* Reset OMAP modules for insmod/rmmod to work */
        ehci_omap_writel(omap->uhh_base, OMAP_UHH_SYSCONFIG,
                        OMAP_UHH_SYSCONFIG_SOFTRESET);
        while (!(ehci_omap_readl(omap->uhh_base, OMAP_UHH_SYSSTATUS)
                                & (1 << 0))) {
                cpu_relax();

                if (time_after(jiffies, timeout))
                        dev_dbg(omap->dev, "operation timed out\n");
        }

        while (!(ehci_omap_readl(omap->uhh_base, OMAP_UHH_SYSSTATUS)
                                & (1 << 1))) {
                cpu_relax();

                if (time_after(jiffies, timeout))
                        dev_dbg(omap->dev, "operation timed out\n");
        }

        while (!(ehci_omap_readl(omap->uhh_base, OMAP_UHH_SYSSTATUS)
                                & (1 << 2))) {
                cpu_relax();

                if (time_after(jiffies, timeout))
                        dev_dbg(omap->dev, "operation timed out\n");
        }

        ehci_omap_writel(omap->tll_base, OMAP_USBTLL_SYSCONFIG, (1 << 1));

        while (!(ehci_omap_readl(omap->tll_base, OMAP_USBTLL_SYSSTATUS)
                                & (1 << 0))) {
                cpu_relax();

                if (time_after(jiffies, timeout))
                        dev_dbg(omap->dev, "operation timed out\n");
        }

        if (omap->usbtll_fck != NULL) {
                clk_disable(omap->usbtll_fck);
                clk_put(omap->usbtll_fck);
                omap->usbtll_fck = NULL;
        }

        if (omap->usbhost_ick != NULL) {
                clk_disable(omap->usbhost_ick);
                clk_put(omap->usbhost_ick);
                omap->usbhost_ick = NULL;
        }

        if (omap->usbhost1_48m_fck != NULL) {
                clk_disable(omap->usbhost1_48m_fck);
                clk_put(omap->usbhost1_48m_fck);
                omap->usbhost1_48m_fck = NULL;
        }

        if (omap->usbhost2_120m_fck != NULL) {
                clk_disable(omap->usbhost2_120m_fck);
                clk_put(omap->usbhost2_120m_fck);
                omap->usbhost2_120m_fck = NULL;
        }

        if (omap->usbtll_ick != NULL) {
                clk_disable(omap->usbtll_ick);
                clk_put(omap->usbtll_ick);
                omap->usbtll_ick = NULL;
        }

        if (omap->phy_reset) {
                if (gpio_is_valid(omap->reset_gpio_port[0]))
                        gpio_free(omap->reset_gpio_port[0]);

                if (gpio_is_valid(omap->reset_gpio_port[1]))
                        gpio_free(omap->reset_gpio_port[1]);
        }

        dev_dbg(omap->dev, "Clock to USB host has been disabled\n");
}

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

static const struct hc_driver ehci_omap_hc_driver;

/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */

/**
 * ehci_hcd_omap_probe - initialize TI-based HCDs
 *
 * Allocates basic resources for this USB host controller, and
 * then invokes the start() method for the HCD associated with it
 * through the hotplug entry's driver_data.
 */
static int ehci_hcd_omap_probe(struct platform_device *pdev)
{
        struct ehci_hcd_omap_platform_data *pdata = pdev->dev.platform_data;
        struct ehci_hcd_omap *omap;
        struct resource *res;
        struct usb_hcd *hcd;

        int irq = platform_get_irq(pdev, 0);
        int ret = -ENODEV;
        int i;
        char supply[7];

        if (!pdata) {
                dev_dbg(&pdev->dev, "missing platform_data\n");
                goto err_pdata;
        }

        if (usb_disabled())
                goto err_disabled;

        omap = kzalloc(sizeof(*omap), GFP_KERNEL);
        if (!omap) {
                ret = -ENOMEM;
                goto err_disabled;
        }

        hcd = usb_create_hcd(&ehci_omap_hc_driver, &pdev->dev,
                        dev_name(&pdev->dev));
        if (!hcd) {
                dev_dbg(&pdev->dev, "failed to create hcd with err %d\n", ret);
                ret = -ENOMEM;
                goto err_create_hcd;
        }

        platform_set_drvdata(pdev, omap);
        omap->dev               = &pdev->dev;
        omap->phy_reset         = pdata->phy_reset;
        omap->reset_gpio_port[0]        = pdata->reset_gpio_port[0];
        omap->reset_gpio_port[1]        = pdata->reset_gpio_port[1];
        omap->reset_gpio_port[2]        = pdata->reset_gpio_port[2];
        omap->port_mode[0]              = pdata->port_mode[0];
        omap->port_mode[1]              = pdata->port_mode[1];
        omap->port_mode[2]              = pdata->port_mode[2];
        omap->ehci              = hcd_to_ehci(hcd);
        omap->ehci->sbrn        = 0x20;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

        hcd->rsrc_start = res->start;
        hcd->rsrc_len = resource_size(res);

        hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
        if (!hcd->regs) {
                dev_err(&pdev->dev, "EHCI ioremap failed\n");
                ret = -ENOMEM;
                goto err_ioremap;
        }

        /* we know this is the memory we want, no need to ioremap again */
        omap->ehci->caps = hcd->regs;
        omap->ehci_base = hcd->regs;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
        omap->uhh_base = ioremap(res->start, resource_size(res));
        if (!omap->uhh_base) {
                dev_err(&pdev->dev, "UHH ioremap failed\n");
                ret = -ENOMEM;
                goto err_uhh_ioremap;
        }

        res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
        omap->tll_base = ioremap(res->start, resource_size(res));
        if (!omap->tll_base) {
                dev_err(&pdev->dev, "TLL ioremap failed\n");
                ret = -ENOMEM;
                goto err_tll_ioremap;
        }

        /* get ehci regulator and enable */
        for (i = 0 ; i < OMAP3_HS_USB_PORTS ; i++) {
                if (omap->port_mode[i] != EHCI_HCD_OMAP_MODE_PHY) {
                        omap->regulator[i] = NULL;
                        continue;
                }
                snprintf(supply, sizeof(supply), "hsusb%d", i);
                omap->regulator[i] = regulator_get(omap->dev, supply);
                if (IS_ERR(omap->regulator[i])) {
                        omap->regulator[i] = NULL;
                        dev_dbg(&pdev->dev,
                        "failed to get ehci port%d regulator\n", i);
                } else {
                        regulator_enable(omap->regulator[i]);
                }
        }

        ret = omap_start_ehc(omap, hcd);
        if (ret) {
                dev_dbg(&pdev->dev, "failed to start ehci\n");
                goto err_start;
        }

        omap->ehci->regs = hcd->regs
                + HC_LENGTH(readl(&omap->ehci->caps->hc_capbase));

        dbg_hcs_params(omap->ehci, "reset");
        dbg_hcc_params(omap->ehci, "reset");

        /* cache this readonly data; minimize chip reads */
        omap->ehci->hcs_params = readl(&omap->ehci->caps->hcs_params);

        ret = usb_add_hcd(hcd, irq, IRQF_DISABLED | IRQF_SHARED);
        if (ret) {
                dev_dbg(&pdev->dev, "failed to add hcd with err %d\n", ret);
                goto err_add_hcd;
        }

        /* root ports should always stay powered */
        ehci_port_power(omap->ehci, 1);

        return 0;

err_add_hcd:
        omap_stop_ehc(omap, hcd);

err_start:
        for (i = 0 ; i < OMAP3_HS_USB_PORTS ; i++) {
                if (omap->regulator[i]) {
                        regulator_disable(omap->regulator[i]);
                        regulator_put(omap->regulator[i]);
                }
        }
        iounmap(omap->tll_base);

err_tll_ioremap:
        iounmap(omap->uhh_base);

err_uhh_ioremap:
        iounmap(hcd->regs);

err_ioremap:
        usb_put_hcd(hcd);

err_create_hcd:
        kfree(omap);
err_disabled:
err_pdata:
        return ret;
}

/* may be called without controller electrically present */
/* may be called with controller, bus, and devices active */

/**
 * ehci_hcd_omap_remove - shutdown processing for EHCI HCDs
 * @pdev: USB Host Controller being removed
 *
 * Reverses the effect of usb_ehci_hcd_omap_probe(), first invoking
 * the HCD's stop() method.  It is always called from a thread
 * context, normally "rmmod", "apmd", or something similar.
 */
static int ehci_hcd_omap_remove(struct platform_device *pdev)
{
        struct ehci_hcd_omap *omap = platform_get_drvdata(pdev);
        struct usb_hcd *hcd = ehci_to_hcd(omap->ehci);
        int i;

        usb_remove_hcd(hcd);
        omap_stop_ehc(omap, hcd);
        iounmap(hcd->regs);
        for (i = 0 ; i < OMAP3_HS_USB_PORTS ; i++) {
                if (omap->regulator[i]) {
                        regulator_disable(omap->regulator[i]);
                        regulator_put(omap->regulator[i]);
                }
        }
        iounmap(omap->tll_base);
        iounmap(omap->uhh_base);
        usb_put_hcd(hcd);
        kfree(omap);

        return 0;
}

static void ehci_hcd_omap_shutdown(struct platform_device *pdev)
{
        struct ehci_hcd_omap *omap = platform_get_drvdata(pdev);
        struct usb_hcd *hcd = ehci_to_hcd(omap->ehci);

        if (hcd->driver->shutdown)
                hcd->driver->shutdown(hcd);
}

static struct platform_driver ehci_hcd_omap_driver = {
        .probe                  = ehci_hcd_omap_probe,
        .remove                 = ehci_hcd_omap_remove,
        .shutdown               = ehci_hcd_omap_shutdown,
        /*.suspend              = ehci_hcd_omap_suspend, */
        /*.resume               = ehci_hcd_omap_resume, */
        .driver = {
                .name           = "ehci-omap",
        }
};

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

static const struct hc_driver ehci_omap_hc_driver = {
        .description            = hcd_name,
        .product_desc           = "OMAP-EHCI Host Controller",
        .hcd_priv_size          = sizeof(struct ehci_hcd),

        /*
         * generic hardware linkage
         */
        .irq                    = ehci_irq,
        .flags                  = HCD_MEMORY | HCD_USB2,

        /*
         * basic lifecycle operations
         */
        .reset                  = ehci_init,
        .start                  = ehci_run,
        .stop                   = ehci_stop,
        .shutdown               = ehci_shutdown,

        /*
         * managing i/o requests and associated device resources
         */
        .urb_enqueue            = ehci_urb_enqueue,
        .urb_dequeue            = ehci_urb_dequeue,
        .endpoint_disable       = ehci_endpoint_disable,
        .endpoint_reset         = ehci_endpoint_reset,

        /*
         * scheduling support
         */
        .get_frame_number       = ehci_get_frame,

        /*
         * root hub support
         */
        .hub_status_data        = ehci_hub_status_data,
        .hub_control            = ehci_hub_control,
        .bus_suspend            = ehci_bus_suspend,
        .bus_resume             = ehci_bus_resume,

        .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
};

MODULE_ALIAS("platform:omap-ehci");
MODULE_AUTHOR("Texas Instruments, Inc.");
MODULE_AUTHOR("Felipe Balbi <felipe.balbi@nokia.com>");