/*
 * TUSB6010 USB 2.0 OTG Dual Role controller
 *
 * Copyright (C) 2006 Nokia Corporation
 * Tony Lindgren <tony@atomide.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 as
 * published by the Free Software Foundation.
 *
 * Notes:
 * - Driver assumes that interface to external host (main CPU) is
 *   configured for NOR FLASH interface instead of VLYNQ serial
 *   interface.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/prefetch.h>
#include <linux/usb.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/usb/usb_phy_gen_xceiv.h>

#include "musb_core.h"

struct tusb6010_glue {
        struct device           *dev;
        struct platform_device  *musb;
};

static void tusb_musb_set_vbus(struct musb *musb, int is_on);

#define TUSB_REV_MAJOR(reg_val)         ((reg_val >> 4) & 0xf)
#define TUSB_REV_MINOR(reg_val)         (reg_val & 0xf)

/*
 * Checks the revision. We need to use the DMA register as 3.0 does not
 * have correct versions for TUSB_PRCM_REV or TUSB_INT_CTRL_REV.
 */
u8 tusb_get_revision(struct musb *musb)
{
        void __iomem    *tbase = musb->ctrl_base;
        u32             die_id;
        u8              rev;

        rev = musb_readl(tbase, TUSB_DMA_CTRL_REV) & 0xff;
        if (TUSB_REV_MAJOR(rev) == 3) {
                die_id = TUSB_DIDR1_HI_CHIP_REV(musb_readl(tbase,
                                TUSB_DIDR1_HI));
                if (die_id >= TUSB_DIDR1_HI_REV_31)
                        rev |= 1;
        }

        return rev;
}
EXPORT_SYMBOL_GPL(tusb_get_revision);

static int tusb_print_revision(struct musb *musb)
{
        void __iomem    *tbase = musb->ctrl_base;
        u8              rev;

        rev = tusb_get_revision(musb);

        pr_info("tusb: %s%i.%i %s%i.%i %s%i.%i %s%i.%i %s%i %s%i.%i\n",
                "prcm",
                TUSB_REV_MAJOR(musb_readl(tbase, TUSB_PRCM_REV)),
                TUSB_REV_MINOR(musb_readl(tbase, TUSB_PRCM_REV)),
                "int",
                TUSB_REV_MAJOR(musb_readl(tbase, TUSB_INT_CTRL_REV)),
                TUSB_REV_MINOR(musb_readl(tbase, TUSB_INT_CTRL_REV)),
                "gpio",
                TUSB_REV_MAJOR(musb_readl(tbase, TUSB_GPIO_REV)),
                TUSB_REV_MINOR(musb_readl(tbase, TUSB_GPIO_REV)),
                "dma",
                TUSB_REV_MAJOR(musb_readl(tbase, TUSB_DMA_CTRL_REV)),
                TUSB_REV_MINOR(musb_readl(tbase, TUSB_DMA_CTRL_REV)),
                "dieid",
                TUSB_DIDR1_HI_CHIP_REV(musb_readl(tbase, TUSB_DIDR1_HI)),
                "rev",
                TUSB_REV_MAJOR(rev), TUSB_REV_MINOR(rev));

        return tusb_get_revision(musb);
}

#define WBUS_QUIRK_MASK (TUSB_PHY_OTG_CTRL_TESTM2 | TUSB_PHY_OTG_CTRL_TESTM1 \
                                | TUSB_PHY_OTG_CTRL_TESTM0)

/*
 * Workaround for spontaneous WBUS wake-up issue #2 for tusb3.0.
 * Disables power detection in PHY for the duration of idle.
 */
static void tusb_wbus_quirk(struct musb *musb, int enabled)
{
        void __iomem    *tbase = musb->ctrl_base;
        static u32      phy_otg_ctrl, phy_otg_ena;
        u32             tmp;

        if (enabled) {
                phy_otg_ctrl = musb_readl(tbase, TUSB_PHY_OTG_CTRL);
                phy_otg_ena = musb_readl(tbase, TUSB_PHY_OTG_CTRL_ENABLE);
                tmp = TUSB_PHY_OTG_CTRL_WRPROTECT
                                | phy_otg_ena | WBUS_QUIRK_MASK;
                musb_writel(tbase, TUSB_PHY_OTG_CTRL, tmp);
                tmp = phy_otg_ena & ~WBUS_QUIRK_MASK;
                tmp |= TUSB_PHY_OTG_CTRL_WRPROTECT | TUSB_PHY_OTG_CTRL_TESTM2;
                musb_writel(tbase, TUSB_PHY_OTG_CTRL_ENABLE, tmp);
                dev_dbg(musb->controller, "Enabled tusb wbus quirk ctrl %08x ena %08x\n",
                        musb_readl(tbase, TUSB_PHY_OTG_CTRL),
                        musb_readl(tbase, TUSB_PHY_OTG_CTRL_ENABLE));
        } else if (musb_readl(tbase, TUSB_PHY_OTG_CTRL_ENABLE)
                                        & TUSB_PHY_OTG_CTRL_TESTM2) {
                tmp = TUSB_PHY_OTG_CTRL_WRPROTECT | phy_otg_ctrl;
                musb_writel(tbase, TUSB_PHY_OTG_CTRL, tmp);
                tmp = TUSB_PHY_OTG_CTRL_WRPROTECT | phy_otg_ena;
                musb_writel(tbase, TUSB_PHY_OTG_CTRL_ENABLE, tmp);
                dev_dbg(musb->controller, "Disabled tusb wbus quirk ctrl %08x ena %08x\n",
                        musb_readl(tbase, TUSB_PHY_OTG_CTRL),
                        musb_readl(tbase, TUSB_PHY_OTG_CTRL_ENABLE));
                phy_otg_ctrl = 0;
                phy_otg_ena = 0;
        }
}

/*
 * TUSB 6010 may use a parallel bus that doesn't support byte ops;
 * so both loading and unloading FIFOs need explicit byte counts.
 */

static inline void
tusb_fifo_write_unaligned(void __iomem *fifo, const u8 *buf, u16 len)
{
        u32             val;
        int             i;

        if (len > 4) {
                for (i = 0; i < (len >> 2); i++) {
                        memcpy(&val, buf, 4);
                        musb_writel(fifo, 0, val);
                        buf += 4;
                }
                len %= 4;
        }
        if (len > 0) {
                /* Write the rest 1 - 3 bytes to FIFO */
                memcpy(&val, buf, len);
                musb_writel(fifo, 0, val);
        }
}

static inline void tusb_fifo_read_unaligned(void __iomem *fifo,
                                                void *buf, u16 len)
{
        u32             val;
        int             i;

        if (len > 4) {
                for (i = 0; i < (len >> 2); i++) {
                        val = musb_readl(fifo, 0);
                        memcpy(buf, &val, 4);
                        buf += 4;
                }
                len %= 4;
        }
        if (len > 0) {
                /* Read the rest 1 - 3 bytes from FIFO */
                val = musb_readl(fifo, 0);
                memcpy(buf, &val, len);
        }
}

void musb_write_fifo(struct musb_hw_ep *hw_ep, u16 len, const u8 *buf)
{
        struct musb *musb = hw_ep->musb;
        void __iomem    *ep_conf = hw_ep->conf;
        void __iomem    *fifo = hw_ep->fifo;
        u8              epnum = hw_ep->epnum;

        prefetch(buf);

        dev_dbg(musb->controller, "%cX ep%d fifo %p count %d buf %p\n",
                        'T', epnum, fifo, len, buf);

        if (epnum)
                musb_writel(ep_conf, TUSB_EP_TX_OFFSET,
                        TUSB_EP_CONFIG_XFR_SIZE(len));
        else
                musb_writel(ep_conf, 0, TUSB_EP0_CONFIG_DIR_TX |
                        TUSB_EP0_CONFIG_XFR_SIZE(len));

        if (likely((0x01 & (unsigned long) buf) == 0)) {

                /* Best case is 32bit-aligned destination address */
                if ((0x02 & (unsigned long) buf) == 0) {
                        if (len >= 4) {
                                iowrite32_rep(fifo, buf, len >> 2);
                                buf += (len & ~0x03);
                                len &= 0x03;
                        }
                } else {
                        if (len >= 2) {
                                u32 val;
                                int i;

                                /* Cannot use writesw, fifo is 32-bit */
                                for (i = 0; i < (len >> 2); i++) {
                                        val = (u32)(*(u16 *)buf);
                                        buf += 2;
                                        val |= (*(u16 *)buf) << 16;
                                        buf += 2;
                                        musb_writel(fifo, 0, val);
                                }
                                len &= 0x03;
                        }
                }
        }

        if (len > 0)
                tusb_fifo_write_unaligned(fifo, buf, len);
}

void musb_read_fifo(struct musb_hw_ep *hw_ep, u16 len, u8 *buf)
{
        struct musb *musb = hw_ep->musb;
        void __iomem    *ep_conf = hw_ep->conf;
        void __iomem    *fifo = hw_ep->fifo;
        u8              epnum = hw_ep->epnum;

        dev_dbg(musb->controller, "%cX ep%d fifo %p count %d buf %p\n",
                        'R', epnum, fifo, len, buf);

        if (epnum)
                musb_writel(ep_conf, TUSB_EP_RX_OFFSET,
                        TUSB_EP_CONFIG_XFR_SIZE(len));
        else
                musb_writel(ep_conf, 0, TUSB_EP0_CONFIG_XFR_SIZE(len));

        if (likely((0x01 & (unsigned long) buf) == 0)) {

                /* Best case is 32bit-aligned destination address */
                if ((0x02 & (unsigned long) buf) == 0) {
                        if (len >= 4) {
                                ioread32_rep(fifo, buf, len >> 2);
                                buf += (len & ~0x03);
                                len &= 0x03;
                        }
                } else {
                        if (len >= 2) {
                                u32 val;
                                int i;

                                /* Cannot use readsw, fifo is 32-bit */
                                for (i = 0; i < (len >> 2); i++) {
                                        val = musb_readl(fifo, 0);
                                        *(u16 *)buf = (u16)(val & 0xffff);
                                        buf += 2;
                                        *(u16 *)buf = (u16)(val >> 16);
                                        buf += 2;
                                }
                                len &= 0x03;
                        }
                }
        }

        if (len > 0)
                tusb_fifo_read_unaligned(fifo, buf, len);
}

static struct musb *the_musb;

/* This is used by gadget drivers, and OTG transceiver logic, allowing
 * at most mA current to be drawn from VBUS during a Default-B session
 * (that is, while VBUS exceeds 4.4V).  In Default-A (including pure host
 * mode), or low power Default-B sessions, something else supplies power.
 * Caller must take care of locking.
 */
static int tusb_draw_power(struct usb_phy *x, unsigned mA)
{
        struct musb     *musb = the_musb;
        void __iomem    *tbase = musb->ctrl_base;
        u32             reg;

        /* tps65030 seems to consume max 100mA, with maybe 60mA available
         * (measured on one board) for things other than tps and tusb.
         *
         * Boards sharing the CPU clock with CLKIN will need to prevent
         * certain idle sleep states while the USB link is active.
         *
         * REVISIT we could use VBUS to supply only _one_ of { 1.5V, 3.3V }.
         * The actual current usage would be very board-specific.  For now,
         * it's simpler to just use an aggregate (also board-specific).
         */
        if (x->otg->default_a || mA < (musb->min_power << 1))
                mA = 0;

        reg = musb_readl(tbase, TUSB_PRCM_MNGMT);
        if (mA) {
                musb->is_bus_powered = 1;
                reg |= TUSB_PRCM_MNGMT_15_SW_EN | TUSB_PRCM_MNGMT_33_SW_EN;
        } else {
                musb->is_bus_powered = 0;
                reg &= ~(TUSB_PRCM_MNGMT_15_SW_EN | TUSB_PRCM_MNGMT_33_SW_EN);
        }
        musb_writel(tbase, TUSB_PRCM_MNGMT, reg);

        dev_dbg(musb->controller, "draw max %d mA VBUS\n", mA);
        return 0;
}

/* workaround for issue 13:  change clock during chip idle
 * (to be fixed in rev3 silicon) ... symptoms include disconnect
 * or looping suspend/resume cycles
 */
static void tusb_set_clock_source(struct musb *musb, unsigned mode)
{
        void __iomem    *tbase = musb->ctrl_base;
        u32             reg;

        reg = musb_readl(tbase, TUSB_PRCM_CONF);
        reg &= ~TUSB_PRCM_CONF_SYS_CLKSEL(0x3);

        /* 0 = refclk (clkin, XI)
         * 1 = PHY 60 MHz (internal PLL)
         * 2 = not supported
         * 3 = what?
         */
        if (mode > 0)
                reg |= TUSB_PRCM_CONF_SYS_CLKSEL(mode & 0x3);

        musb_writel(tbase, TUSB_PRCM_CONF, reg);

        /* FIXME tusb6010_platform_retime(mode == 0); */
}

/*
 * Idle TUSB6010 until next wake-up event; NOR access always wakes.
 * Other code ensures that we idle unless we're connected _and_ the
 * USB link is not suspended ... and tells us the relevant wakeup
 * events.  SW_EN for voltage is handled separately.
 */
static void tusb_allow_idle(struct musb *musb, u32 wakeup_enables)
{
        void __iomem    *tbase = musb->ctrl_base;
        u32             reg;

        if ((wakeup_enables & TUSB_PRCM_WBUS)
                        && (tusb_get_revision(musb) == TUSB_REV_30))
                tusb_wbus_quirk(musb, 1);

        tusb_set_clock_source(musb, 0);

        wakeup_enables |= TUSB_PRCM_WNORCS;
        musb_writel(tbase, TUSB_PRCM_WAKEUP_MASK, ~wakeup_enables);

        /* REVISIT writeup of WID implies that if WID set and ID is grounded,
         * TUSB_PHY_OTG_CTRL.TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP must be cleared.
         * Presumably that's mostly to save power, hence WID is immaterial ...
         */

        reg = musb_readl(tbase, TUSB_PRCM_MNGMT);
        /* issue 4: when driving vbus, use hipower (vbus_det) comparator */
        if (is_host_active(musb)) {
                reg |= TUSB_PRCM_MNGMT_OTG_VBUS_DET_EN;
                reg &= ~TUSB_PRCM_MNGMT_OTG_SESS_END_EN;
        } else {
                reg |= TUSB_PRCM_MNGMT_OTG_SESS_END_EN;
                reg &= ~TUSB_PRCM_MNGMT_OTG_VBUS_DET_EN;
        }
        reg |= TUSB_PRCM_MNGMT_PM_IDLE | TUSB_PRCM_MNGMT_DEV_IDLE;
        musb_writel(tbase, TUSB_PRCM_MNGMT, reg);

        dev_dbg(musb->controller, "idle, wake on %02x\n", wakeup_enables);
}

/*
 * Updates cable VBUS status. Caller must take care of locking.
 */
static int tusb_musb_vbus_status(struct musb *musb)
{
        void __iomem    *tbase = musb->ctrl_base;
        u32             otg_stat, prcm_mngmt;
        int             ret = 0;

        otg_stat = musb_readl(tbase, TUSB_DEV_OTG_STAT);
        prcm_mngmt = musb_readl(tbase, TUSB_PRCM_MNGMT);

        /* Temporarily enable VBUS detection if it was disabled for
         * suspend mode. Unless it's enabled otg_stat and devctl will
         * not show correct VBUS state.
         */
        if (!(prcm_mngmt & TUSB_PRCM_MNGMT_OTG_VBUS_DET_EN)) {
                u32 tmp = prcm_mngmt;
                tmp |= TUSB_PRCM_MNGMT_OTG_VBUS_DET_EN;
                musb_writel(tbase, TUSB_PRCM_MNGMT, tmp);
                otg_stat = musb_readl(tbase, TUSB_DEV_OTG_STAT);
                musb_writel(tbase, TUSB_PRCM_MNGMT, prcm_mngmt);
        }

        if (otg_stat & TUSB_DEV_OTG_STAT_VBUS_VALID)
                ret = 1;

        return ret;
}

static struct timer_list musb_idle_timer;

static void musb_do_idle(unsigned long _musb)
{
        struct musb     *musb = (void *)_musb;
        unsigned long   flags;

        spin_lock_irqsave(&musb->lock, flags);

        switch (musb->xceiv->state) {
        case OTG_STATE_A_WAIT_BCON:
                if ((musb->a_wait_bcon != 0)
                        && (musb->idle_timeout == 0
                                || time_after(jiffies, musb->idle_timeout))) {
                        dev_dbg(musb->controller, "Nothing connected %s, turning off VBUS\n",
                                        usb_otg_state_string(musb->xceiv->state));
                }
                /* FALLTHROUGH */
        case OTG_STATE_A_IDLE:
                tusb_musb_set_vbus(musb, 0);
        default:
                break;
        }

        if (!musb->is_active) {
                u32     wakeups;

                /* wait until khubd handles port change status */
                if (is_host_active(musb) && (musb->port1_status >> 16))
                        goto done;

                if (!musb->gadget_driver) {
                        wakeups = 0;
                } else {
                        wakeups = TUSB_PRCM_WHOSTDISCON
                                | TUSB_PRCM_WBUS
                                        | TUSB_PRCM_WVBUS;
                        wakeups |= TUSB_PRCM_WID;
                }
                tusb_allow_idle(musb, wakeups);
        }
done:
        spin_unlock_irqrestore(&musb->lock, flags);
}

/*
 * Maybe put TUSB6010 into idle mode mode depending on USB link status,
 * like "disconnected" or "suspended".  We'll be woken out of it by
 * connect, resume, or disconnect.
 *
 * Needs to be called as the last function everywhere where there is
 * register access to TUSB6010 because of NOR flash wake-up.
 * Caller should own controller spinlock.
 *
 * Delay because peripheral enables D+ pullup 3msec after SE0, and
 * we don't want to treat that full speed J as a wakeup event.
 * ... peripherals must draw only suspend current after 10 msec.
 */
static void tusb_musb_try_idle(struct musb *musb, unsigned long timeout)
{
        unsigned long           default_timeout = jiffies + msecs_to_jiffies(3);
        static unsigned long    last_timer;

        if (timeout == 0)
                timeout = default_timeout;

        /* Never idle if active, or when VBUS timeout is not set as host */
        if (musb->is_active || ((musb->a_wait_bcon == 0)
                        && (musb->xceiv->state == OTG_STATE_A_WAIT_BCON))) {
                dev_dbg(musb->controller, "%s active, deleting timer\n",
                        usb_otg_state_string(musb->xceiv->state));
                del_timer(&musb_idle_timer);
                last_timer = jiffies;
                return;
        }

        if (time_after(last_timer, timeout)) {
                if (!timer_pending(&musb_idle_timer))
                        last_timer = timeout;
                else {
                        dev_dbg(musb->controller, "Longer idle timer already pending, ignoring\n");
                        return;
                }
        }
        last_timer = timeout;

        dev_dbg(musb->controller, "%s inactive, for idle timer for %lu ms\n",
                usb_otg_state_string(musb->xceiv->state),
                (unsigned long)jiffies_to_msecs(timeout - jiffies));
        mod_timer(&musb_idle_timer, timeout);
}

/* ticks of 60 MHz clock */
#define DEVCLOCK                60000000
#define OTG_TIMER_MS(msecs)     ((msecs) \
                ? (TUSB_DEV_OTG_TIMER_VAL((DEVCLOCK/1000)*(msecs)) \
                                | TUSB_DEV_OTG_TIMER_ENABLE) \
                : 0)

static void tusb_musb_set_vbus(struct musb *musb, int is_on)
{
        void __iomem    *tbase = musb->ctrl_base;
        u32             conf, prcm, timer;
        u8              devctl;
        struct usb_otg  *otg = musb->xceiv->otg;

        /* HDRC controls CPEN, but beware current surges during device
         * connect.  They can trigger transient overcurrent conditions
         * that must be ignored.
         */

        prcm = musb_readl(tbase, TUSB_PRCM_MNGMT);
        conf = musb_readl(tbase, TUSB_DEV_CONF);
        devctl = musb_readb(musb->mregs, MUSB_DEVCTL);

        if (is_on) {
                timer = OTG_TIMER_MS(OTG_TIME_A_WAIT_VRISE);
                otg->default_a = 1;
                musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
                devctl |= MUSB_DEVCTL_SESSION;

                conf |= TUSB_DEV_CONF_USB_HOST_MODE;
                MUSB_HST_MODE(musb);
        } else {
                u32     otg_stat;

                timer = 0;

                /* If ID pin is grounded, we want to be a_idle */
                otg_stat = musb_readl(tbase, TUSB_DEV_OTG_STAT);
                if (!(otg_stat & TUSB_DEV_OTG_STAT_ID_STATUS)) {
                        switch (musb->xceiv->state) {
                        case OTG_STATE_A_WAIT_VRISE:
                        case OTG_STATE_A_WAIT_BCON:
                                musb->xceiv->state = OTG_STATE_A_WAIT_VFALL;
                                break;
                        case OTG_STATE_A_WAIT_VFALL:
                                musb->xceiv->state = OTG_STATE_A_IDLE;
                                break;
                        default:
                                musb->xceiv->state = OTG_STATE_A_IDLE;
                        }
                        musb->is_active = 0;
                        otg->default_a = 1;
                        MUSB_HST_MODE(musb);
                } else {
                        musb->is_active = 0;
                        otg->default_a = 0;
                        musb->xceiv->state = OTG_STATE_B_IDLE;
                        MUSB_DEV_MODE(musb);
                }

                devctl &= ~MUSB_DEVCTL_SESSION;
                conf &= ~TUSB_DEV_CONF_USB_HOST_MODE;
        }
        prcm &= ~(TUSB_PRCM_MNGMT_15_SW_EN | TUSB_PRCM_MNGMT_33_SW_EN);

        musb_writel(tbase, TUSB_PRCM_MNGMT, prcm);
        musb_writel(tbase, TUSB_DEV_OTG_TIMER, timer);
        musb_writel(tbase, TUSB_DEV_CONF, conf);
        musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);

        dev_dbg(musb->controller, "VBUS %s, devctl %02x otg %3x conf %08x prcm %08x\n",
                usb_otg_state_string(musb->xceiv->state),
                musb_readb(musb->mregs, MUSB_DEVCTL),
                musb_readl(tbase, TUSB_DEV_OTG_STAT),
                conf, prcm);
}

/*
 * Sets the mode to OTG, peripheral or host by changing the ID detection.
 * Caller must take care of locking.
 *
 * Note that if a mini-A cable is plugged in the ID line will stay down as
 * the weak ID pull-up is not able to pull the ID up.
 */
static int tusb_musb_set_mode(struct musb *musb, u8 musb_mode)
{
        void __iomem    *tbase = musb->ctrl_base;
        u32             otg_stat, phy_otg_ctrl, phy_otg_ena, dev_conf;

        otg_stat = musb_readl(tbase, TUSB_DEV_OTG_STAT);
        phy_otg_ctrl = musb_readl(tbase, TUSB_PHY_OTG_CTRL);
        phy_otg_ena = musb_readl(tbase, TUSB_PHY_OTG_CTRL_ENABLE);
        dev_conf = musb_readl(tbase, TUSB_DEV_CONF);

        switch (musb_mode) {

        case MUSB_HOST:         /* Disable PHY ID detect, ground ID */
                phy_otg_ctrl &= ~TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
                phy_otg_ena |= TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
                dev_conf |= TUSB_DEV_CONF_ID_SEL;
                dev_conf &= ~TUSB_DEV_CONF_SOFT_ID;
                break;
        case MUSB_PERIPHERAL:   /* Disable PHY ID detect, keep ID pull-up on */
                phy_otg_ctrl |= TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
                phy_otg_ena |= TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
                dev_conf |= (TUSB_DEV_CONF_ID_SEL | TUSB_DEV_CONF_SOFT_ID);
                break;
        case MUSB_OTG:          /* Use PHY ID detection */
                phy_otg_ctrl |= TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
                phy_otg_ena |= TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
                dev_conf &= ~(TUSB_DEV_CONF_ID_SEL | TUSB_DEV_CONF_SOFT_ID);
                break;

        default:
                dev_dbg(musb->controller, "Trying to set mode %i\n", musb_mode);
                return -EINVAL;
        }

        musb_writel(tbase, TUSB_PHY_OTG_CTRL,
                        TUSB_PHY_OTG_CTRL_WRPROTECT | phy_otg_ctrl);
        musb_writel(tbase, TUSB_PHY_OTG_CTRL_ENABLE,
                        TUSB_PHY_OTG_CTRL_WRPROTECT | phy_otg_ena);
        musb_writel(tbase, TUSB_DEV_CONF, dev_conf);

        otg_stat = musb_readl(tbase, TUSB_DEV_OTG_STAT);
        if ((musb_mode == MUSB_PERIPHERAL) &&
                !(otg_stat & TUSB_DEV_OTG_STAT_ID_STATUS))
                        INFO("Cannot be peripheral with mini-A cable "
                        "otg_stat: %08x\n", otg_stat);

        return 0;
}

static inline unsigned long
tusb_otg_ints(struct musb *musb, u32 int_src, void __iomem *tbase)
{
        u32             otg_stat = musb_readl(tbase, TUSB_DEV_OTG_STAT);
        unsigned long   idle_timeout = 0;
        struct usb_otg  *otg = musb->xceiv->otg;

        /* ID pin */
        if ((int_src & TUSB_INT_SRC_ID_STATUS_CHNG)) {
                int     default_a;

                default_a = !(otg_stat & TUSB_DEV_OTG_STAT_ID_STATUS);
                dev_dbg(musb->controller, "Default-%c\n", default_a ? 'A' : 'B');
                otg->default_a = default_a;
                tusb_musb_set_vbus(musb, default_a);

                /* Don't allow idling immediately */
                if (default_a)
                        idle_timeout = jiffies + (HZ * 3);
        }

        /* VBUS state change */
        if (int_src & TUSB_INT_SRC_VBUS_SENSE_CHNG) {

                /* B-dev state machine:  no vbus ~= disconnect */
                if (!otg->default_a) {
                        /* ? musb_root_disconnect(musb); */
                        musb->port1_status &=
                                ~(USB_PORT_STAT_CONNECTION
                                | USB_PORT_STAT_ENABLE
                                | USB_PORT_STAT_LOW_SPEED
                                | USB_PORT_STAT_HIGH_SPEED
                                | USB_PORT_STAT_TEST
                                );

                        if (otg_stat & TUSB_DEV_OTG_STAT_SESS_END) {
                                dev_dbg(musb->controller, "Forcing disconnect (no interrupt)\n");
                                if (musb->xceiv->state != OTG_STATE_B_IDLE) {
                                        /* INTR_DISCONNECT can hide... */
                                        musb->xceiv->state = OTG_STATE_B_IDLE;
                                        musb->int_usb |= MUSB_INTR_DISCONNECT;
                                }
                                musb->is_active = 0;
                        }
                        dev_dbg(musb->controller, "vbus change, %s, otg %03x\n",
                                usb_otg_state_string(musb->xceiv->state), otg_stat);
                        idle_timeout = jiffies + (1 * HZ);
                        schedule_work(&musb->irq_work);

                } else /* A-dev state machine */ {
                        dev_dbg(musb->controller, "vbus change, %s, otg %03x\n",
                                usb_otg_state_string(musb->xceiv->state), otg_stat);

                        switch (musb->xceiv->state) {
                        case OTG_STATE_A_IDLE:
                                dev_dbg(musb->controller, "Got SRP, turning on VBUS\n");
                                musb_platform_set_vbus(musb, 1);

                                /* CONNECT can wake if a_wait_bcon is set */
                                if (musb->a_wait_bcon != 0)
                                        musb->is_active = 0;
                                else
                                        musb->is_active = 1;

                                /*
                                 * OPT FS A TD.4.6 needs few seconds for
                                 * A_WAIT_VRISE
                                 */
                                idle_timeout = jiffies + (2 * HZ);

                                break;
                        case OTG_STATE_A_WAIT_VRISE:
                                /* ignore; A-session-valid < VBUS_VALID/2,
                                 * we monitor this with the timer
                                 */
                                break;
                        case OTG_STATE_A_WAIT_VFALL:
                                /* REVISIT this irq triggers during short
                                 * spikes caused by enumeration ...
                                 */
                                if (musb->vbuserr_retry) {
                                        musb->vbuserr_retry--;
                                        tusb_musb_set_vbus(musb, 1);
                                } else {
                                        musb->vbuserr_retry
                                                = VBUSERR_RETRY_COUNT;
                                        tusb_musb_set_vbus(musb, 0);
                                }
                                break;
                        default:
                                break;
                        }
                }
        }

        /* OTG timer expiration */
        if (int_src & TUSB_INT_SRC_OTG_TIMEOUT) {
                u8      devctl;

                dev_dbg(musb->controller, "%s timer, %03x\n",
                        usb_otg_state_string(musb->xceiv->state), otg_stat);

                switch (musb->xceiv->state) {
                case OTG_STATE_A_WAIT_VRISE:
                        /* VBUS has probably been valid for a while now,
                         * but may well have bounced out of range a bit
                         */
                        devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
                        if (otg_stat & TUSB_DEV_OTG_STAT_VBUS_VALID) {
                                if ((devctl & MUSB_DEVCTL_VBUS)
                                                != MUSB_DEVCTL_VBUS) {
                                        dev_dbg(musb->controller, "devctl %02x\n", devctl);
                                        break;
                                }
                                musb->xceiv->state = OTG_STATE_A_WAIT_BCON;
                                musb->is_active = 0;
                                idle_timeout = jiffies
                                        + msecs_to_jiffies(musb->a_wait_bcon);
                        } else {
                                /* REVISIT report overcurrent to hub? */
                                ERR("vbus too slow, devctl %02x\n", devctl);
                                tusb_musb_set_vbus(musb, 0);
                        }
                        break;
                case OTG_STATE_A_WAIT_BCON:
                        if (musb->a_wait_bcon != 0)
                                idle_timeout = jiffies
                                        + msecs_to_jiffies(musb->a_wait_bcon);
                        break;
                case OTG_STATE_A_SUSPEND:
                        break;
                case OTG_STATE_B_WAIT_ACON:
                        break;
                default:
                        break;
                }
        }
        schedule_work(&musb->irq_work);

        return idle_timeout;
}

static irqreturn_t tusb_musb_interrupt(int irq, void *__hci)
{
        struct musb     *musb = __hci;
        void __iomem    *tbase = musb->ctrl_base;
        unsigned long   flags, idle_timeout = 0;
        u32             int_mask, int_src;

        spin_lock_irqsave(&musb->lock, flags);

        /* Mask all interrupts to allow using both edge and level GPIO irq */
        int_mask = musb_readl(tbase, TUSB_INT_MASK);
        musb_writel(tbase, TUSB_INT_MASK, ~TUSB_INT_MASK_RESERVED_BITS);

        int_src = musb_readl(tbase, TUSB_INT_SRC) & ~TUSB_INT_SRC_RESERVED_BITS;
        dev_dbg(musb->controller, "TUSB IRQ %08x\n", int_src);

        musb->int_usb = (u8) int_src;

        /* Acknowledge wake-up source interrupts */
        if (int_src & TUSB_INT_SRC_DEV_WAKEUP) {
                u32     reg;
                u32     i;

                if (tusb_get_revision(musb) == TUSB_REV_30)
                        tusb_wbus_quirk(musb, 0);

                /* there are issues re-locking the PLL on wakeup ... */

                /* work around issue 8 */
                for (i = 0xf7f7f7; i > 0xf7f7f7 - 1000; i--) {
                        musb_writel(tbase, TUSB_SCRATCH_PAD, 0);
                        musb_writel(tbase, TUSB_SCRATCH_PAD, i);
                        reg = musb_readl(tbase, TUSB_SCRATCH_PAD);
                        if (reg == i)
                                break;
                        dev_dbg(musb->controller, "TUSB NOR not ready\n");
                }

                /* work around issue 13 (2nd half) */
                tusb_set_clock_source(musb, 1);

                reg = musb_readl(tbase, TUSB_PRCM_WAKEUP_SOURCE);
                musb_writel(tbase, TUSB_PRCM_WAKEUP_CLEAR, reg);
                if (reg & ~TUSB_PRCM_WNORCS) {
                        musb->is_active = 1;
                        schedule_work(&musb->irq_work);
                }
                dev_dbg(musb->controller, "wake %sactive %02x\n",
                                musb->is_active ? "" : "in", reg);

                /* REVISIT host side TUSB_PRCM_WHOSTDISCON, TUSB_PRCM_WBUS */
        }

        if (int_src & TUSB_INT_SRC_USB_IP_CONN)
                del_timer(&musb_idle_timer);

        /* OTG state change reports (annoyingly) not issued by Mentor core */
        if (int_src & (TUSB_INT_SRC_VBUS_SENSE_CHNG
                                | TUSB_INT_SRC_OTG_TIMEOUT
                                | TUSB_INT_SRC_ID_STATUS_CHNG))
                idle_timeout = tusb_otg_ints(musb, int_src, tbase);

        /* TX dma callback must be handled here, RX dma callback is
         * handled in tusb_omap_dma_cb.
         */
        if ((int_src & TUSB_INT_SRC_TXRX_DMA_DONE)) {
                u32     dma_src = musb_readl(tbase, TUSB_DMA_INT_SRC);
                u32     real_dma_src = musb_readl(tbase, TUSB_DMA_INT_MASK);

                dev_dbg(musb->controller, "DMA IRQ %08x\n", dma_src);
                real_dma_src = ~real_dma_src & dma_src;
                if (tusb_dma_omap() && real_dma_src) {
                        int     tx_source = (real_dma_src & 0xffff);
                        int     i;

                        for (i = 1; i <= 15; i++) {
                                if (tx_source & (1 << i)) {
                                        dev_dbg(musb->controller, "completing ep%i %s\n", i, "tx");
                                        musb_dma_completion(musb, i, 1);
                                }
                        }
                }
                musb_writel(tbase, TUSB_DMA_INT_CLEAR, dma_src);
        }

        /* EP interrupts. In OCP mode tusb6010 mirrors the MUSB interrupts */
        if (int_src & (TUSB_INT_SRC_USB_IP_TX | TUSB_INT_SRC_USB_IP_RX)) {
                u32     musb_src = musb_readl(tbase, TUSB_USBIP_INT_SRC);

                musb_writel(tbase, TUSB_USBIP_INT_CLEAR, musb_src);
                musb->int_rx = (((musb_src >> 16) & 0xffff) << 1);
                musb->int_tx = (musb_src & 0xffff);
        } else {
                musb->int_rx = 0;
                musb->int_tx = 0;
        }

        if (int_src & (TUSB_INT_SRC_USB_IP_TX | TUSB_INT_SRC_USB_IP_RX | 0xff))
                musb_interrupt(musb);

        /* Acknowledge TUSB interrupts. Clear only non-reserved bits */
        musb_writel(tbase, TUSB_INT_SRC_CLEAR,
                int_src & ~TUSB_INT_MASK_RESERVED_BITS);

        tusb_musb_try_idle(musb, idle_timeout);

        musb_writel(tbase, TUSB_INT_MASK, int_mask);
        spin_unlock_irqrestore(&musb->lock, flags);

        return IRQ_HANDLED;
}

static int dma_off;

/*
 * Enables TUSB6010. Caller must take care of locking.
 * REVISIT:
 * - Check what is unnecessary in MGC_HdrcStart()
 */
static void tusb_musb_enable(struct musb *musb)
{
        void __iomem    *tbase = musb->ctrl_base;

        /* Setup TUSB6010 main interrupt mask. Enable all interrupts except SOF.
         * REVISIT: Enable and deal with TUSB_INT_SRC_USB_IP_SOF */
        musb_writel(tbase, TUSB_INT_MASK, TUSB_INT_SRC_USB_IP_SOF);

        /* Setup TUSB interrupt, disable DMA and GPIO interrupts */
        musb_writel(tbase, TUSB_USBIP_INT_MASK, 0);
        musb_writel(tbase, TUSB_DMA_INT_MASK, 0x7fffffff);
        musb_writel(tbase, TUSB_GPIO_INT_MASK, 0x1ff);

        /* Clear all subsystem interrups */
        musb_writel(tbase, TUSB_USBIP_INT_CLEAR, 0x7fffffff);
        musb_writel(tbase, TUSB_DMA_INT_CLEAR, 0x7fffffff);
        musb_writel(tbase, TUSB_GPIO_INT_CLEAR, 0x1ff);

        /* Acknowledge pending interrupt(s) */
        musb_writel(tbase, TUSB_INT_SRC_CLEAR, ~TUSB_INT_MASK_RESERVED_BITS);

        /* Only 0 clock cycles for minimum interrupt de-assertion time and
         * interrupt polarity active low seems to work reliably here */
        musb_writel(tbase, TUSB_INT_CTRL_CONF,
                        TUSB_INT_CTRL_CONF_INT_RELCYC(0));

        irq_set_irq_type(musb->nIrq, IRQ_TYPE_LEVEL_LOW);

        /* maybe force into the Default-A OTG state machine */
        if (!(musb_readl(tbase, TUSB_DEV_OTG_STAT)
                        & TUSB_DEV_OTG_STAT_ID_STATUS))
                musb_writel(tbase, TUSB_INT_SRC_SET,
                                TUSB_INT_SRC_ID_STATUS_CHNG);

        if (is_dma_capable() && dma_off)
                printk(KERN_WARNING "%s %s: dma not reactivated\n",
                                __FILE__, __func__);
        else
                dma_off = 1;
}

/*
 * Disables TUSB6010. Caller must take care of locking.
 */
static void tusb_musb_disable(struct musb *musb)
{
        void __iomem    *tbase = musb->ctrl_base;

        /* FIXME stop DMA, IRQs, timers, ... */

        /* disable all IRQs */
        musb_writel(tbase, TUSB_INT_MASK, ~TUSB_INT_MASK_RESERVED_BITS);
        musb_writel(tbase, TUSB_USBIP_INT_MASK, 0x7fffffff);
        musb_writel(tbase, TUSB_DMA_INT_MASK, 0x7fffffff);
        musb_writel(tbase, TUSB_GPIO_INT_MASK, 0x1ff);

        del_timer(&musb_idle_timer);

        if (is_dma_capable() && !dma_off) {
                printk(KERN_WARNING "%s %s: dma still active\n",
                                __FILE__, __func__);
                dma_off = 1;
        }
}

/*
 * Sets up TUSB6010 CPU interface specific signals and registers
 * Note: Settings optimized for OMAP24xx
 */
static void tusb_setup_cpu_interface(struct musb *musb)
{
        void __iomem    *tbase = musb->ctrl_base;

        /*
         * Disable GPIO[5:0] pullups (used as output DMA requests)
         * Don't disable GPIO[7:6] as they are needed for wake-up.
         */
        musb_writel(tbase, TUSB_PULLUP_1_CTRL, 0x0000003F);

        /* Disable all pullups on NOR IF, DMAREQ0 and DMAREQ1 */
        musb_writel(tbase, TUSB_PULLUP_2_CTRL, 0x01FFFFFF);

        /* Turn GPIO[5:0] to DMAREQ[5:0] signals */
        musb_writel(tbase, TUSB_GPIO_CONF, TUSB_GPIO_CONF_DMAREQ(0x3f));

        /* Burst size 16x16 bits, all six DMA requests enabled, DMA request
         * de-assertion time 2 system clocks p 62 */
        musb_writel(tbase, TUSB_DMA_REQ_CONF,
                TUSB_DMA_REQ_CONF_BURST_SIZE(2) |
                TUSB_DMA_REQ_CONF_DMA_REQ_EN(0x3f) |
                TUSB_DMA_REQ_CONF_DMA_REQ_ASSER(2));

        /* Set 0 wait count for synchronous burst access */
        musb_writel(tbase, TUSB_WAIT_COUNT, 1);
}

static int tusb_musb_start(struct musb *musb)
{
        void __iomem    *tbase = musb->ctrl_base;
        int             ret = 0;
        unsigned long   flags;
        u32             reg;

        if (musb->board_set_power)

                ret = musb->board_set_power(1);
        if (ret != 0) {
                printk(KERN_ERR "tusb: Cannot enable TUSB6010\n");
                return ret;
        }

        spin_lock_irqsave(&musb->lock, flags);

        if (musb_readl(tbase, TUSB_PROD_TEST_RESET) !=
                TUSB_PROD_TEST_RESET_VAL) {
                printk(KERN_ERR "tusb: Unable to detect TUSB6010\n");
                goto err;
        }

        ret = tusb_print_revision(musb);
        if (ret < 2) {
                printk(KERN_ERR "tusb: Unsupported TUSB6010 revision %i\n",
                                ret);
                goto err;
        }

        /* The uint bit for "USB non-PDR interrupt enable" has to be 1 when
         * NOR FLASH interface is used */
        musb_writel(tbase, TUSB_VLYNQ_CTRL, 8);

        /* Select PHY free running 60MHz as a system clock */
        tusb_set_clock_source(musb, 1);

        /* VBus valid timer 1us, disable DFT/Debug and VLYNQ clocks for
         * power saving, enable VBus detect and session end comparators,
         * enable IDpullup, enable VBus charging */
        musb_writel(tbase, TUSB_PRCM_MNGMT,
                TUSB_PRCM_MNGMT_VBUS_VALID_TIMER(0xa) |
                TUSB_PRCM_MNGMT_VBUS_VALID_FLT_EN |
                TUSB_PRCM_MNGMT_OTG_SESS_END_EN |
                TUSB_PRCM_MNGMT_OTG_VBUS_DET_EN |
                TUSB_PRCM_MNGMT_OTG_ID_PULLUP);
        tusb_setup_cpu_interface(musb);

        /* simplify:  always sense/pullup ID pins, as if in OTG mode */
        reg = musb_readl(tbase, TUSB_PHY_OTG_CTRL_ENABLE);
        reg |= TUSB_PHY_OTG_CTRL_WRPROTECT | TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
        musb_writel(tbase, TUSB_PHY_OTG_CTRL_ENABLE, reg);

        reg = musb_readl(tbase, TUSB_PHY_OTG_CTRL);
        reg |= TUSB_PHY_OTG_CTRL_WRPROTECT | TUSB_PHY_OTG_CTRL_OTG_ID_PULLUP;
        musb_writel(tbase, TUSB_PHY_OTG_CTRL, reg);

        spin_unlock_irqrestore(&musb->lock, flags);

        return 0;

err:
        spin_unlock_irqrestore(&musb->lock, flags);

        if (musb->board_set_power)
                musb->board_set_power(0);

        return -ENODEV;
}

static int tusb_musb_init(struct musb *musb)
{
        struct platform_device  *pdev;
        struct resource         *mem;
        void __iomem            *sync = NULL;
        int                     ret;

        usb_nop_xceiv_register();
        musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
        if (IS_ERR_OR_NULL(musb->xceiv))
                return -EPROBE_DEFER;

        pdev = to_platform_device(musb->controller);

        /* dma address for async dma */
        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        musb->async = mem->start;

        /* dma address for sync dma */
        mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
        if (!mem) {
                pr_debug("no sync dma resource?\n");
                ret = -ENODEV;
                goto done;
        }
        musb->sync = mem->start;

        sync = ioremap(mem->start, resource_size(mem));
        if (!sync) {
                pr_debug("ioremap for sync failed\n");
                ret = -ENOMEM;
                goto done;
        }
        musb->sync_va = sync;

        /* Offsets from base: VLYNQ at 0x000, MUSB regs at 0x400,
         * FIFOs at 0x600, TUSB at 0x800
         */
        musb->mregs += TUSB_BASE_OFFSET;

        ret = tusb_musb_start(musb);
        if (ret) {
                printk(KERN_ERR "Could not start tusb6010 (%d)\n",
                                ret);
                goto done;
        }
        musb->isr = tusb_musb_interrupt;

        musb->xceiv->set_power = tusb_draw_power;
        the_musb = musb;

        setup_timer(&musb_idle_timer, musb_do_idle, (unsigned long) musb);

done:
        if (ret < 0) {
                if (sync)
                        iounmap(sync);

                usb_put_phy(musb->xceiv);
                usb_nop_xceiv_unregister();
        }
        return ret;
}

static int tusb_musb_exit(struct musb *musb)
{
        del_timer_sync(&musb_idle_timer);
        the_musb = NULL;

        if (musb->board_set_power)
                musb->board_set_power(0);

        iounmap(musb->sync_va);

        usb_put_phy(musb->xceiv);
        usb_nop_xceiv_unregister();
        return 0;
}

static const struct musb_platform_ops tusb_ops = {
        .init           = tusb_musb_init,
        .exit           = tusb_musb_exit,

        .enable         = tusb_musb_enable,
        .disable        = tusb_musb_disable,

        .set_mode       = tusb_musb_set_mode,
        .try_idle       = tusb_musb_try_idle,

        .vbus_status    = tusb_musb_vbus_status,
        .set_vbus       = tusb_musb_set_vbus,
};

static u64 tusb_dmamask = DMA_BIT_MASK(32);

static int tusb_probe(struct platform_device *pdev)
{
        struct resource musb_resources[3];
        struct musb_hdrc_platform_data  *pdata = dev_get_platdata(&pdev->dev);
        struct platform_device          *musb;
        struct tusb6010_glue            *glue;

        int                             ret = -ENOMEM;

        glue = kzalloc(sizeof(*glue), GFP_KERNEL);
        if (!glue) {
                dev_err(&pdev->dev, "failed to allocate glue context\n");
                goto err0;
        }

        musb = platform_device_alloc("musb-hdrc", PLATFORM_DEVID_AUTO);
        if (!musb) {
                dev_err(&pdev->dev, "failed to allocate musb device\n");
                goto err1;
        }

        musb->dev.parent                = &pdev->dev;
        musb->dev.dma_mask              = &tusb_dmamask;
        musb->dev.coherent_dma_mask     = tusb_dmamask;

        glue->dev                       = &pdev->dev;
        glue->musb                      = musb;

        pdata->platform_ops             = &tusb_ops;

        platform_set_drvdata(pdev, glue);

        memset(musb_resources, 0x00, sizeof(*musb_resources) *
                        ARRAY_SIZE(musb_resources));

        musb_resources[0].name = pdev->resource[0].name;
        musb_resources[0].start = pdev->resource[0].start;
        musb_resources[0].end = pdev->resource[0].end;
        musb_resources[0].flags = pdev->resource[0].flags;

        musb_resources[1].name = pdev->resource[1].name;
        musb_resources[1].start = pdev->resource[1].start;
        musb_resources[1].end = pdev->resource[1].end;
        musb_resources[1].flags = pdev->resource[1].flags;

        musb_resources[2].name = pdev->resource[2].name;
        musb_resources[2].start = pdev->resource[2].start;
        musb_resources[2].end = pdev->resource[2].end;
        musb_resources[2].flags = pdev->resource[2].flags;

        ret = platform_device_add_resources(musb, musb_resources,
                        ARRAY_SIZE(musb_resources));
        if (ret) {
                dev_err(&pdev->dev, "failed to add resources\n");
                goto err3;
        }

        ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
        if (ret) {
                dev_err(&pdev->dev, "failed to add platform_data\n");
                goto err3;
        }

        ret = platform_device_add(musb);
        if (ret) {
                dev_err(&pdev->dev, "failed to register musb device\n");
                goto err3;
        }

        return 0;

err3:
        platform_device_put(musb);

err1:
        kfree(glue);

err0:
        return ret;
}

static int tusb_remove(struct platform_device *pdev)
{
        struct tusb6010_glue            *glue = platform_get_drvdata(pdev);

        platform_device_unregister(glue->musb);
        kfree(glue);

        return 0;
}

static struct platform_driver tusb_driver = {
        .probe          = tusb_probe,
        .remove         = tusb_remove,
        .driver         = {
                .name   = "musb-tusb",
        },
};

MODULE_DESCRIPTION("TUSB6010 MUSB Glue Layer");
MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
MODULE_LICENSE("GPL v2");
module_platform_driver(tusb_driver);