musb_core: don't touch 'musb->clock' in musb_free()

[safe/jmp/linux-2.6] / drivers / usb / musb / musb_core.c

/*
 * MUSB OTG driver core code
 *
 * Copyright 2005 Mentor Graphics Corporation
 * Copyright (C) 2005-2006 by Texas Instruments
 * Copyright (C) 2006-2007 Nokia Corporation
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/*
 * Inventra (Multipoint) Dual-Role Controller Driver for Linux.
 *
 * This consists of a Host Controller Driver (HCD) and a peripheral
 * controller driver implementing the "Gadget" API; OTG support is
 * in the works.  These are normal Linux-USB controller drivers which
 * use IRQs and have no dedicated thread.
 *
 * This version of the driver has only been used with products from
 * Texas Instruments.  Those products integrate the Inventra logic
 * with other DMA, IRQ, and bus modules, as well as other logic that
 * needs to be reflected in this driver.
 *
 *
 * NOTE:  the original Mentor code here was pretty much a collection
 * of mechanisms that don't seem to have been fully integrated/working
 * for *any* Linux kernel version.  This version aims at Linux 2.6.now,
 * Key open issues include:
 *
 *  - Lack of host-side transaction scheduling, for all transfer types.
 *    The hardware doesn't do it; instead, software must.
 *
 *    This is not an issue for OTG devices that don't support external
 *    hubs, but for more "normal" USB hosts it's a user issue that the
 *    "multipoint" support doesn't scale in the expected ways.  That
 *    includes DaVinci EVM in a common non-OTG mode.
 *
 *      * Control and bulk use dedicated endpoints, and there's as
 *        yet no mechanism to either (a) reclaim the hardware when
 *        peripherals are NAKing, which gets complicated with bulk
 *        endpoints, or (b) use more than a single bulk endpoint in
 *        each direction.
 *
 *        RESULT:  one device may be perceived as blocking another one.
 *
 *      * Interrupt and isochronous will dynamically allocate endpoint
 *        hardware, but (a) there's no record keeping for bandwidth;
 *        (b) in the common case that few endpoints are available, there
 *        is no mechanism to reuse endpoints to talk to multiple devices.
 *
 *        RESULT:  At one extreme, bandwidth can be overcommitted in
 *        some hardware configurations, no faults will be reported.
 *        At the other extreme, the bandwidth capabilities which do
 *        exist tend to be severely undercommitted.  You can't yet hook
 *        up both a keyboard and a mouse to an external USB hub.
 */

/*
 * This gets many kinds of configuration information:
 *      - Kconfig for everything user-configurable
 *      - platform_device for addressing, irq, and platform_data
 *      - platform_data is mostly for board-specific informarion
 *        (plus recentrly, SOC or family details)
 *
 * Most of the conditional compilation will (someday) vanish.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/kobject.h>
#include <linux/platform_device.h>
#include <linux/io.h>

#ifdef  CONFIG_ARM
#include <mach/hardware.h>
#include <mach/memory.h>
#include <asm/mach-types.h>
#endif

#include "musb_core.h"


#ifdef CONFIG_ARCH_DAVINCI
#include "davinci.h"
#endif

#define TA_WAIT_BCON(m) max_t(int, (m)->a_wait_bcon, OTG_TIME_A_WAIT_BCON)


unsigned musb_debug;
module_param_named(debug, musb_debug, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug message level. Default = 0");

#define DRIVER_AUTHOR "Mentor Graphics, Texas Instruments, Nokia"
#define DRIVER_DESC "Inventra Dual-Role USB Controller Driver"

#define MUSB_VERSION "6.0"

#define DRIVER_INFO DRIVER_DESC ", v" MUSB_VERSION

#define MUSB_DRIVER_NAME "musb_hdrc"
const char musb_driver_name[] = MUSB_DRIVER_NAME;

MODULE_DESCRIPTION(DRIVER_INFO);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" MUSB_DRIVER_NAME);


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

static inline struct musb *dev_to_musb(struct device *dev)
{
#ifdef CONFIG_USB_MUSB_HDRC_HCD
        /* usbcore insists dev->driver_data is a "struct hcd *" */
        return hcd_to_musb(dev_get_drvdata(dev));
#else
        return dev_get_drvdata(dev);
#endif
}

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

#if !defined(CONFIG_USB_TUSB6010) && !defined(CONFIG_BLACKFIN)

/*
 * Load an endpoint's FIFO
 */
void musb_write_fifo(struct musb_hw_ep *hw_ep, u16 len, const u8 *src)
{
        void __iomem *fifo = hw_ep->fifo;

        prefetch((u8 *)src);

        DBG(4, "%cX ep%d fifo %p count %d buf %p\n",
                        'T', hw_ep->epnum, fifo, len, src);

        /* we can't assume unaligned reads work */
        if (likely((0x01 & (unsigned long) src) == 0)) {
                u16     index = 0;

                /* best case is 32bit-aligned source address */
                if ((0x02 & (unsigned long) src) == 0) {
                        if (len >= 4) {
                                writesl(fifo, src + index, len >> 2);
                                index += len & ~0x03;
                        }
                        if (len & 0x02) {
                                musb_writew(fifo, 0, *(u16 *)&src[index]);
                                index += 2;
                        }
                } else {
                        if (len >= 2) {
                                writesw(fifo, src + index, len >> 1);
                                index += len & ~0x01;
                        }
                }
                if (len & 0x01)
                        musb_writeb(fifo, 0, src[index]);
        } else  {
                /* byte aligned */
                writesb(fifo, src, len);
        }
}

/*
 * Unload an endpoint's FIFO
 */
void musb_read_fifo(struct musb_hw_ep *hw_ep, u16 len, u8 *dst)
{
        void __iomem *fifo = hw_ep->fifo;

        DBG(4, "%cX ep%d fifo %p count %d buf %p\n",
                        'R', hw_ep->epnum, fifo, len, dst);

        /* we can't assume unaligned writes work */
        if (likely((0x01 & (unsigned long) dst) == 0)) {
                u16     index = 0;

                /* best case is 32bit-aligned destination address */
                if ((0x02 & (unsigned long) dst) == 0) {
                        if (len >= 4) {
                                readsl(fifo, dst, len >> 2);
                                index = len & ~0x03;
                        }
                        if (len & 0x02) {
                                *(u16 *)&dst[index] = musb_readw(fifo, 0);
                                index += 2;
                        }
                } else {
                        if (len >= 2) {
                                readsw(fifo, dst, len >> 1);
                                index = len & ~0x01;
                        }
                }
                if (len & 0x01)
                        dst[index] = musb_readb(fifo, 0);
        } else  {
                /* byte aligned */
                readsb(fifo, dst, len);
        }
}

#endif  /* normal PIO */


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

/* for high speed test mode; see USB 2.0 spec 7.1.20 */
static const u8 musb_test_packet[53] = {
        /* implicit SYNC then DATA0 to start */

        /* JKJKJKJK x9 */
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        /* JJKKJJKK x8 */
        0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        /* JJJJKKKK x8 */
        0xee, 0xee, 0xee, 0xee, 0xee, 0xee, 0xee, 0xee,
        /* JJJJJJJKKKKKKK x8 */
        0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
        /* JJJJJJJK x8 */
        0x7f, 0xbf, 0xdf, 0xef, 0xf7, 0xfb, 0xfd,
        /* JKKKKKKK x10, JK */
        0xfc, 0x7e, 0xbf, 0xdf, 0xef, 0xf7, 0xfb, 0xfd, 0x7e

        /* implicit CRC16 then EOP to end */
};

void musb_load_testpacket(struct musb *musb)
{
        void __iomem    *regs = musb->endpoints[0].regs;

        musb_ep_select(musb->mregs, 0);
        musb_write_fifo(musb->control_ep,
                        sizeof(musb_test_packet), musb_test_packet);
        musb_writew(regs, MUSB_CSR0, MUSB_CSR0_TXPKTRDY);
}

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

const char *otg_state_string(struct musb *musb)
{
        switch (musb->xceiv->state) {
        case OTG_STATE_A_IDLE:          return "a_idle";
        case OTG_STATE_A_WAIT_VRISE:    return "a_wait_vrise";
        case OTG_STATE_A_WAIT_BCON:     return "a_wait_bcon";
        case OTG_STATE_A_HOST:          return "a_host";
        case OTG_STATE_A_SUSPEND:       return "a_suspend";
        case OTG_STATE_A_PERIPHERAL:    return "a_peripheral";
        case OTG_STATE_A_WAIT_VFALL:    return "a_wait_vfall";
        case OTG_STATE_A_VBUS_ERR:      return "a_vbus_err";
        case OTG_STATE_B_IDLE:          return "b_idle";
        case OTG_STATE_B_SRP_INIT:      return "b_srp_init";
        case OTG_STATE_B_PERIPHERAL:    return "b_peripheral";
        case OTG_STATE_B_WAIT_ACON:     return "b_wait_acon";
        case OTG_STATE_B_HOST:          return "b_host";
        default:                        return "UNDEFINED";
        }
}

#ifdef  CONFIG_USB_MUSB_OTG

/*
 * Handles OTG hnp timeouts, such as b_ase0_brst
 */
void musb_otg_timer_func(unsigned long data)
{
        struct musb     *musb = (struct musb *)data;
        unsigned long   flags;

        spin_lock_irqsave(&musb->lock, flags);
        switch (musb->xceiv->state) {
        case OTG_STATE_B_WAIT_ACON:
                DBG(1, "HNP: b_wait_acon timeout; back to b_peripheral\n");
                musb_g_disconnect(musb);
                musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
                musb->is_active = 0;
                break;
        case OTG_STATE_A_SUSPEND:
        case OTG_STATE_A_WAIT_BCON:
                DBG(1, "HNP: %s timeout\n", otg_state_string(musb));
                musb_set_vbus(musb, 0);
                musb->xceiv->state = OTG_STATE_A_WAIT_VFALL;
                break;
        default:
                DBG(1, "HNP: Unhandled mode %s\n", otg_state_string(musb));
        }
        musb->ignore_disconnect = 0;
        spin_unlock_irqrestore(&musb->lock, flags);
}

/*
 * Stops the HNP transition. Caller must take care of locking.
 */
void musb_hnp_stop(struct musb *musb)
{
        struct usb_hcd  *hcd = musb_to_hcd(musb);
        void __iomem    *mbase = musb->mregs;
        u8      reg;

        DBG(1, "HNP: stop from %s\n", otg_state_string(musb));

        switch (musb->xceiv->state) {
        case OTG_STATE_A_PERIPHERAL:
                musb_g_disconnect(musb);
                DBG(1, "HNP: back to %s\n", otg_state_string(musb));
                break;
        case OTG_STATE_B_HOST:
                DBG(1, "HNP: Disabling HR\n");
                hcd->self.is_b_host = 0;
                musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
                MUSB_DEV_MODE(musb);
                reg = musb_readb(mbase, MUSB_POWER);
                reg |= MUSB_POWER_SUSPENDM;
                musb_writeb(mbase, MUSB_POWER, reg);
                /* REVISIT: Start SESSION_REQUEST here? */
                break;
        default:
                DBG(1, "HNP: Stopping in unknown state %s\n",
                        otg_state_string(musb));
        }

        /*
         * When returning to A state after HNP, avoid hub_port_rebounce(),
         * which cause occasional OPT A "Did not receive reset after connect"
         * errors.
         */
        musb->port1_status &=
                ~(1 << USB_PORT_FEAT_C_CONNECTION);
}

#endif

/*
 * Interrupt Service Routine to record USB "global" interrupts.
 * Since these do not happen often and signify things of
 * paramount importance, it seems OK to check them individually;
 * the order of the tests is specified in the manual
 *
 * @param musb instance pointer
 * @param int_usb register contents
 * @param devctl
 * @param power
 */

#define STAGE0_MASK (MUSB_INTR_RESUME | MUSB_INTR_SESSREQ \
                | MUSB_INTR_VBUSERROR | MUSB_INTR_CONNECT \
                | MUSB_INTR_RESET)

static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb,
                                u8 devctl, u8 power)
{
        irqreturn_t handled = IRQ_NONE;

        DBG(3, "<== Power=%02x, DevCtl=%02x, int_usb=0x%x\n", power, devctl,
                int_usb);

        /* in host mode, the peripheral may issue remote wakeup.
         * in peripheral mode, the host may resume the link.
         * spurious RESUME irqs happen too, paired with SUSPEND.
         */
        if (int_usb & MUSB_INTR_RESUME) {
                handled = IRQ_HANDLED;
                DBG(3, "RESUME (%s)\n", otg_state_string(musb));

                if (devctl & MUSB_DEVCTL_HM) {
#ifdef CONFIG_USB_MUSB_HDRC_HCD
                        void __iomem *mbase = musb->mregs;

                        switch (musb->xceiv->state) {
                        case OTG_STATE_A_SUSPEND:
                                /* remote wakeup?  later, GetPortStatus
                                 * will stop RESUME signaling
                                 */

                                if (power & MUSB_POWER_SUSPENDM) {
                                        /* spurious */
                                        musb->int_usb &= ~MUSB_INTR_SUSPEND;
                                        DBG(2, "Spurious SUSPENDM\n");
                                        break;
                                }

                                power &= ~MUSB_POWER_SUSPENDM;
                                musb_writeb(mbase, MUSB_POWER,
                                                power | MUSB_POWER_RESUME);

                                musb->port1_status |=
                                                (USB_PORT_STAT_C_SUSPEND << 16)
                                                | MUSB_PORT_STAT_RESUME;
                                musb->rh_timer = jiffies
                                                + msecs_to_jiffies(20);

                                musb->xceiv->state = OTG_STATE_A_HOST;
                                musb->is_active = 1;
                                usb_hcd_resume_root_hub(musb_to_hcd(musb));
                                break;
                        case OTG_STATE_B_WAIT_ACON:
                                musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
                                musb->is_active = 1;
                                MUSB_DEV_MODE(musb);
                                break;
                        default:
                                WARNING("bogus %s RESUME (%s)\n",
                                        "host",
                                        otg_state_string(musb));
                        }
#endif
                } else {
                        switch (musb->xceiv->state) {
#ifdef CONFIG_USB_MUSB_HDRC_HCD
                        case OTG_STATE_A_SUSPEND:
                                /* possibly DISCONNECT is upcoming */
                                musb->xceiv->state = OTG_STATE_A_HOST;
                                usb_hcd_resume_root_hub(musb_to_hcd(musb));
                                break;
#endif
#ifdef CONFIG_USB_GADGET_MUSB_HDRC
                        case OTG_STATE_B_WAIT_ACON:
                        case OTG_STATE_B_PERIPHERAL:
                                /* disconnect while suspended?  we may
                                 * not get a disconnect irq...
                                 */
                                if ((devctl & MUSB_DEVCTL_VBUS)
                                                != (3 << MUSB_DEVCTL_VBUS_SHIFT)
                                                ) {
                                        musb->int_usb |= MUSB_INTR_DISCONNECT;
                                        musb->int_usb &= ~MUSB_INTR_SUSPEND;
                                        break;
                                }
                                musb_g_resume(musb);
                                break;
                        case OTG_STATE_B_IDLE:
                                musb->int_usb &= ~MUSB_INTR_SUSPEND;
                                break;
#endif
                        default:
                                WARNING("bogus %s RESUME (%s)\n",
                                        "peripheral",
                                        otg_state_string(musb));
                        }
                }
        }

#ifdef CONFIG_USB_MUSB_HDRC_HCD
        /* see manual for the order of the tests */
        if (int_usb & MUSB_INTR_SESSREQ) {
                void __iomem *mbase = musb->mregs;

                DBG(1, "SESSION_REQUEST (%s)\n", otg_state_string(musb));

                /* IRQ arrives from ID pin sense or (later, if VBUS power
                 * is removed) SRP.  responses are time critical:
                 *  - turn on VBUS (with silicon-specific mechanism)
                 *  - go through A_WAIT_VRISE
                 *  - ... to A_WAIT_BCON.
                 * a_wait_vrise_tmout triggers VBUS_ERROR transitions
                 */
                musb_writeb(mbase, MUSB_DEVCTL, MUSB_DEVCTL_SESSION);
                musb->ep0_stage = MUSB_EP0_START;
                musb->xceiv->state = OTG_STATE_A_IDLE;
                MUSB_HST_MODE(musb);
                musb_set_vbus(musb, 1);

                handled = IRQ_HANDLED;
        }

        if (int_usb & MUSB_INTR_VBUSERROR) {
                int     ignore = 0;

                /* During connection as an A-Device, we may see a short
                 * current spikes causing voltage drop, because of cable
                 * and peripheral capacitance combined with vbus draw.
                 * (So: less common with truly self-powered devices, where
                 * vbus doesn't act like a power supply.)
                 *
                 * Such spikes are short; usually less than ~500 usec, max
                 * of ~2 msec.  That is, they're not sustained overcurrent
                 * errors, though they're reported using VBUSERROR irqs.
                 *
                 * Workarounds:  (a) hardware: use self powered devices.
                 * (b) software:  ignore non-repeated VBUS errors.
                 *
                 * REVISIT:  do delays from lots of DEBUG_KERNEL checks
                 * make trouble here, keeping VBUS < 4.4V ?
                 */
                switch (musb->xceiv->state) {
                case OTG_STATE_A_HOST:
                        /* recovery is dicey once we've gotten past the
                         * initial stages of enumeration, but if VBUS
                         * stayed ok at the other end of the link, and
                         * another reset is due (at least for high speed,
                         * to redo the chirp etc), it might work OK...
                         */
                case OTG_STATE_A_WAIT_BCON:
                case OTG_STATE_A_WAIT_VRISE:
                        if (musb->vbuserr_retry) {
                                void __iomem *mbase = musb->mregs;

                                musb->vbuserr_retry--;
                                ignore = 1;
                                devctl |= MUSB_DEVCTL_SESSION;
                                musb_writeb(mbase, MUSB_DEVCTL, devctl);
                        } else {
                                musb->port1_status |=
                                          (1 << USB_PORT_FEAT_OVER_CURRENT)
                                        | (1 << USB_PORT_FEAT_C_OVER_CURRENT);
                        }
                        break;
                default:
                        break;
                }

                DBG(1, "VBUS_ERROR in %s (%02x, %s), retry #%d, port1 %08x\n",
                                otg_state_string(musb),
                                devctl,
                                ({ char *s;
                                switch (devctl & MUSB_DEVCTL_VBUS) {
                                case 0 << MUSB_DEVCTL_VBUS_SHIFT:
                                        s = "<SessEnd"; break;
                                case 1 << MUSB_DEVCTL_VBUS_SHIFT:
                                        s = "<AValid"; break;
                                case 2 << MUSB_DEVCTL_VBUS_SHIFT:
                                        s = "<VBusValid"; break;
                                /* case 3 << MUSB_DEVCTL_VBUS_SHIFT: */
                                default:
                                        s = "VALID"; break;
                                }; s; }),
                                VBUSERR_RETRY_COUNT - musb->vbuserr_retry,
                                musb->port1_status);

                /* go through A_WAIT_VFALL then start a new session */
                if (!ignore)
                        musb_set_vbus(musb, 0);
                handled = IRQ_HANDLED;
        }


        if (int_usb & MUSB_INTR_SUSPEND) {
                DBG(1, "SUSPEND (%s) devctl %02x power %02x\n",
                                otg_state_string(musb), devctl, power);
                handled = IRQ_HANDLED;

                switch (musb->xceiv->state) {
#ifdef  CONFIG_USB_MUSB_OTG
                case OTG_STATE_A_PERIPHERAL:
                        /* We also come here if the cable is removed, since
                         * this silicon doesn't report ID-no-longer-grounded.
                         *
                         * We depend on T(a_wait_bcon) to shut us down, and
                         * hope users don't do anything dicey during this
                         * undesired detour through A_WAIT_BCON.
                         */
                        musb_hnp_stop(musb);
                        usb_hcd_resume_root_hub(musb_to_hcd(musb));
                        musb_root_disconnect(musb);
                        musb_platform_try_idle(musb, jiffies
                                        + msecs_to_jiffies(musb->a_wait_bcon
                                                ? : OTG_TIME_A_WAIT_BCON));

                        break;
#endif
                case OTG_STATE_B_IDLE:
                        if (!musb->is_active)
                                break;
                case OTG_STATE_B_PERIPHERAL:
                        musb_g_suspend(musb);
                        musb->is_active = is_otg_enabled(musb)
                                        && musb->xceiv->gadget->b_hnp_enable;
                        if (musb->is_active) {
#ifdef  CONFIG_USB_MUSB_OTG
                                musb->xceiv->state = OTG_STATE_B_WAIT_ACON;
                                DBG(1, "HNP: Setting timer for b_ase0_brst\n");
                                mod_timer(&musb->otg_timer, jiffies
                                        + msecs_to_jiffies(
                                                        OTG_TIME_B_ASE0_BRST));
#endif
                        }
                        break;
                case OTG_STATE_A_WAIT_BCON:
                        if (musb->a_wait_bcon != 0)
                                musb_platform_try_idle(musb, jiffies
                                        + msecs_to_jiffies(musb->a_wait_bcon));
                        break;
                case OTG_STATE_A_HOST:
                        musb->xceiv->state = OTG_STATE_A_SUSPEND;
                        musb->is_active = is_otg_enabled(musb)
                                        && musb->xceiv->host->b_hnp_enable;
                        break;
                case OTG_STATE_B_HOST:
                        /* Transition to B_PERIPHERAL, see 6.8.2.6 p 44 */
                        DBG(1, "REVISIT: SUSPEND as B_HOST\n");
                        break;
                default:
                        /* "should not happen" */
                        musb->is_active = 0;
                        break;
                }
        }

        if (int_usb & MUSB_INTR_CONNECT) {
                struct usb_hcd *hcd = musb_to_hcd(musb);
                void __iomem *mbase = musb->mregs;

                handled = IRQ_HANDLED;
                musb->is_active = 1;
                set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);

                musb->ep0_stage = MUSB_EP0_START;

#ifdef CONFIG_USB_MUSB_OTG
                /* flush endpoints when transitioning from Device Mode */
                if (is_peripheral_active(musb)) {
                        /* REVISIT HNP; just force disconnect */
                }
                musb_writew(mbase, MUSB_INTRTXE, musb->epmask);
                musb_writew(mbase, MUSB_INTRRXE, musb->epmask & 0xfffe);
                musb_writeb(mbase, MUSB_INTRUSBE, 0xf7);
#endif
                musb->port1_status &= ~(USB_PORT_STAT_LOW_SPEED
                                        |USB_PORT_STAT_HIGH_SPEED
                                        |USB_PORT_STAT_ENABLE
                                        );
                musb->port1_status |= USB_PORT_STAT_CONNECTION
                                        |(USB_PORT_STAT_C_CONNECTION << 16);

                /* high vs full speed is just a guess until after reset */
                if (devctl & MUSB_DEVCTL_LSDEV)
                        musb->port1_status |= USB_PORT_STAT_LOW_SPEED;

                /* indicate new connection to OTG machine */
                switch (musb->xceiv->state) {
                case OTG_STATE_B_PERIPHERAL:
                        if (int_usb & MUSB_INTR_SUSPEND) {
                                DBG(1, "HNP: SUSPEND+CONNECT, now b_host\n");
                                int_usb &= ~MUSB_INTR_SUSPEND;
                                goto b_host;
                        } else
                                DBG(1, "CONNECT as b_peripheral???\n");
                        break;
                case OTG_STATE_B_WAIT_ACON:
                        DBG(1, "HNP: CONNECT, now b_host\n");
b_host:
                        musb->xceiv->state = OTG_STATE_B_HOST;
                        hcd->self.is_b_host = 1;
                        musb->ignore_disconnect = 0;
                        del_timer(&musb->otg_timer);
                        break;
                default:
                        if ((devctl & MUSB_DEVCTL_VBUS)
                                        == (3 << MUSB_DEVCTL_VBUS_SHIFT)) {
                                musb->xceiv->state = OTG_STATE_A_HOST;
                                hcd->self.is_b_host = 0;
                        }
                        break;
                }

                /* poke the root hub */
                MUSB_HST_MODE(musb);
                if (hcd->status_urb)
                        usb_hcd_poll_rh_status(hcd);
                else
                        usb_hcd_resume_root_hub(hcd);

                DBG(1, "CONNECT (%s) devctl %02x\n",
                                otg_state_string(musb), devctl);
        }
#endif  /* CONFIG_USB_MUSB_HDRC_HCD */

        if ((int_usb & MUSB_INTR_DISCONNECT) && !musb->ignore_disconnect) {
                DBG(1, "DISCONNECT (%s) as %s, devctl %02x\n",
                                otg_state_string(musb),
                                MUSB_MODE(musb), devctl);
                handled = IRQ_HANDLED;

                switch (musb->xceiv->state) {
#ifdef CONFIG_USB_MUSB_HDRC_HCD
                case OTG_STATE_A_HOST:
                case OTG_STATE_A_SUSPEND:
                        usb_hcd_resume_root_hub(musb_to_hcd(musb));
                        musb_root_disconnect(musb);
                        if (musb->a_wait_bcon != 0 && is_otg_enabled(musb))
                                musb_platform_try_idle(musb, jiffies
                                        + msecs_to_jiffies(musb->a_wait_bcon));
                        break;
#endif  /* HOST */
#ifdef CONFIG_USB_MUSB_OTG
                case OTG_STATE_B_HOST:
                        /* REVISIT this behaves for "real disconnect"
                         * cases; make sure the other transitions from
                         * from B_HOST act right too.  The B_HOST code
                         * in hnp_stop() is currently not used...
                         */
                        musb_root_disconnect(musb);
                        musb_to_hcd(musb)->self.is_b_host = 0;
                        musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
                        MUSB_DEV_MODE(musb);
                        musb_g_disconnect(musb);
                        break;
                case OTG_STATE_A_PERIPHERAL:
                        musb_hnp_stop(musb);
                        musb_root_disconnect(musb);
                        /* FALLTHROUGH */
                case OTG_STATE_B_WAIT_ACON:
                        /* FALLTHROUGH */
#endif  /* OTG */
#ifdef CONFIG_USB_GADGET_MUSB_HDRC
                case OTG_STATE_B_PERIPHERAL:
                case OTG_STATE_B_IDLE:
                        musb_g_disconnect(musb);
                        break;
#endif  /* GADGET */
                default:
                        WARNING("unhandled DISCONNECT transition (%s)\n",
                                otg_state_string(musb));
                        break;
                }
        }

        /* mentor saves a bit: bus reset and babble share the same irq.
         * only host sees babble; only peripheral sees bus reset.
         */
        if (int_usb & MUSB_INTR_RESET) {
                handled = IRQ_HANDLED;
                if (is_host_capable() && (devctl & MUSB_DEVCTL_HM) != 0) {
                        /*
                         * Looks like non-HS BABBLE can be ignored, but
                         * HS BABBLE is an error condition. For HS the solution
                         * is to avoid babble in the first place and fix what
                         * caused BABBLE. When HS BABBLE happens we can only
                         * stop the session.
                         */
                        if (devctl & (MUSB_DEVCTL_FSDEV | MUSB_DEVCTL_LSDEV))
                                DBG(1, "BABBLE devctl: %02x\n", devctl);
                        else {
                                ERR("Stopping host session -- babble\n");
                                musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
                        }
                } else if (is_peripheral_capable()) {
                        DBG(1, "BUS RESET as %s\n", otg_state_string(musb));
                        switch (musb->xceiv->state) {
#ifdef CONFIG_USB_OTG
                        case OTG_STATE_A_SUSPEND:
                                /* We need to ignore disconnect on suspend
                                 * otherwise tusb 2.0 won't reconnect after a
                                 * power cycle, which breaks otg compliance.
                                 */
                                musb->ignore_disconnect = 1;
                                musb_g_reset(musb);
                                /* FALLTHROUGH */
                        case OTG_STATE_A_WAIT_BCON:     /* OPT TD.4.7-900ms */
                                /* never use invalid T(a_wait_bcon) */
                                DBG(1, "HNP: in %s, %d msec timeout\n",
                                                otg_state_string(musb),
                                                TA_WAIT_BCON(musb));
                                mod_timer(&musb->otg_timer, jiffies
                                        + msecs_to_jiffies(TA_WAIT_BCON(musb)));
                                break;
                        case OTG_STATE_A_PERIPHERAL:
                                musb->ignore_disconnect = 0;
                                del_timer(&musb->otg_timer);
                                musb_g_reset(musb);
                                break;
                        case OTG_STATE_B_WAIT_ACON:
                                DBG(1, "HNP: RESET (%s), to b_peripheral\n",
                                        otg_state_string(musb));
                                musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
                                musb_g_reset(musb);
                                break;
#endif
                        case OTG_STATE_B_IDLE:
                                musb->xceiv->state = OTG_STATE_B_PERIPHERAL;
                                /* FALLTHROUGH */
                        case OTG_STATE_B_PERIPHERAL:
                                musb_g_reset(musb);
                                break;
                        default:
                                DBG(1, "Unhandled BUS RESET as %s\n",
                                        otg_state_string(musb));
                        }
                }
        }

#if 0
/* REVISIT ... this would be for multiplexing periodic endpoints, or
 * supporting transfer phasing to prevent exceeding ISO bandwidth
 * limits of a given frame or microframe.
 *
 * It's not needed for peripheral side, which dedicates endpoints;
 * though it _might_ use SOF irqs for other purposes.
 *
 * And it's not currently needed for host side, which also dedicates
 * endpoints, relies on TX/RX interval registers, and isn't claimed
 * to support ISO transfers yet.
 */
        if (int_usb & MUSB_INTR_SOF) {
                void __iomem *mbase = musb->mregs;
                struct musb_hw_ep       *ep;
                u8 epnum;
                u16 frame;

                DBG(6, "START_OF_FRAME\n");
                handled = IRQ_HANDLED;

                /* start any periodic Tx transfers waiting for current frame */
                frame = musb_readw(mbase, MUSB_FRAME);
                ep = musb->endpoints;
                for (epnum = 1; (epnum < musb->nr_endpoints)
                                        && (musb->epmask >= (1 << epnum));
                                epnum++, ep++) {
                        /*
                         * FIXME handle framecounter wraps (12 bits)
                         * eliminate duplicated StartUrb logic
                         */
                        if (ep->dwWaitFrame >= frame) {
                                ep->dwWaitFrame = 0;
                                pr_debug("SOF --> periodic TX%s on %d\n",
                                        ep->tx_channel ? " DMA" : "",
                                        epnum);
                                if (!ep->tx_channel)
                                        musb_h_tx_start(musb, epnum);
                                else
                                        cppi_hostdma_start(musb, epnum);
                        }
                }               /* end of for loop */
        }
#endif

        schedule_work(&musb->irq_work);

        return handled;
}

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

/*
* Program the HDRC to start (enable interrupts, dma, etc.).
*/
void musb_start(struct musb *musb)
{
        void __iomem    *regs = musb->mregs;
        u8              devctl = musb_readb(regs, MUSB_DEVCTL);

        DBG(2, "<== devctl %02x\n", devctl);

        /*  Set INT enable registers, enable interrupts */
        musb_writew(regs, MUSB_INTRTXE, musb->epmask);
        musb_writew(regs, MUSB_INTRRXE, musb->epmask & 0xfffe);
        musb_writeb(regs, MUSB_INTRUSBE, 0xf7);

        musb_writeb(regs, MUSB_TESTMODE, 0);

        /* put into basic highspeed mode and start session */
        musb_writeb(regs, MUSB_POWER, MUSB_POWER_ISOUPDATE
                                                | MUSB_POWER_SOFTCONN
                                                | MUSB_POWER_HSENAB
                                                /* ENSUSPEND wedges tusb */
                                                /* | MUSB_POWER_ENSUSPEND */
                                                );

        musb->is_active = 0;
        devctl = musb_readb(regs, MUSB_DEVCTL);
        devctl &= ~MUSB_DEVCTL_SESSION;

        if (is_otg_enabled(musb)) {
                /* session started after:
                 * (a) ID-grounded irq, host mode;
                 * (b) vbus present/connect IRQ, peripheral mode;
                 * (c) peripheral initiates, using SRP
                 */
                if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
                        musb->is_active = 1;
                else
                        devctl |= MUSB_DEVCTL_SESSION;

        } else if (is_host_enabled(musb)) {
                /* assume ID pin is hard-wired to ground */
                devctl |= MUSB_DEVCTL_SESSION;

        } else /* peripheral is enabled */ {
                if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
                        musb->is_active = 1;
        }
        musb_platform_enable(musb);
        musb_writeb(regs, MUSB_DEVCTL, devctl);
}


static void musb_generic_disable(struct musb *musb)
{
        void __iomem    *mbase = musb->mregs;
        u16     temp;

        /* disable interrupts */
        musb_writeb(mbase, MUSB_INTRUSBE, 0);
        musb_writew(mbase, MUSB_INTRTXE, 0);
        musb_writew(mbase, MUSB_INTRRXE, 0);

        /* off */
        musb_writeb(mbase, MUSB_DEVCTL, 0);

        /*  flush pending interrupts */
        temp = musb_readb(mbase, MUSB_INTRUSB);
        temp = musb_readw(mbase, MUSB_INTRTX);
        temp = musb_readw(mbase, MUSB_INTRRX);

}

/*
 * Make the HDRC stop (disable interrupts, etc.);
 * reversible by musb_start
 * called on gadget driver unregister
 * with controller locked, irqs blocked
 * acts as a NOP unless some role activated the hardware
 */
void musb_stop(struct musb *musb)
{
        /* stop IRQs, timers, ... */
        musb_platform_disable(musb);
        musb_generic_disable(musb);
        DBG(3, "HDRC disabled\n");

        /* FIXME
         *  - mark host and/or peripheral drivers unusable/inactive
         *  - disable DMA (and enable it in HdrcStart)
         *  - make sure we can musb_start() after musb_stop(); with
         *    OTG mode, gadget driver module rmmod/modprobe cycles that
         *  - ...
         */
        musb_platform_try_idle(musb, 0);
}

static void musb_shutdown(struct platform_device *pdev)
{
        struct musb     *musb = dev_to_musb(&pdev->dev);
        unsigned long   flags;

        spin_lock_irqsave(&musb->lock, flags);
        musb_platform_disable(musb);
        musb_generic_disable(musb);
        if (musb->clock) {
                clk_put(musb->clock);
                musb->clock = NULL;
        }
        spin_unlock_irqrestore(&musb->lock, flags);

        /* FIXME power down */
}


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

/*
 * The silicon either has hard-wired endpoint configurations, or else
 * "dynamic fifo" sizing.  The driver has support for both, though at this
 * writing only the dynamic sizing is very well tested.   Since we switched
 * away from compile-time hardware parameters, we can no longer rely on
 * dead code elimination to leave only the relevant one in the object file.
 *
 * We don't currently use dynamic fifo setup capability to do anything
 * more than selecting one of a bunch of predefined configurations.
 */
#if defined(CONFIG_USB_TUSB6010) || \
        defined(CONFIG_ARCH_OMAP2430) || defined(CONFIG_ARCH_OMAP3)
static ushort __initdata fifo_mode = 4;
#else
static ushort __initdata fifo_mode = 2;
#endif

/* "modprobe ... fifo_mode=1" etc */
module_param(fifo_mode, ushort, 0);
MODULE_PARM_DESC(fifo_mode, "initial endpoint configuration");


enum fifo_style { FIFO_RXTX, FIFO_TX, FIFO_RX } __attribute__ ((packed));
enum buf_mode { BUF_SINGLE, BUF_DOUBLE } __attribute__ ((packed));

struct fifo_cfg {
        u8              hw_ep_num;
        enum fifo_style style;
        enum buf_mode   mode;
        u16             maxpacket;
};

/*
 * tables defining fifo_mode values.  define more if you like.
 * for host side, make sure both halves of ep1 are set up.
 */

/* mode 0 - fits in 2KB */
static struct fifo_cfg __initdata mode_0_cfg[] = {
{ .hw_ep_num = 1, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num = 1, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num = 2, .style = FIFO_RXTX, .maxpacket = 512, },
{ .hw_ep_num = 3, .style = FIFO_RXTX, .maxpacket = 256, },
{ .hw_ep_num = 4, .style = FIFO_RXTX, .maxpacket = 256, },
};

/* mode 1 - fits in 4KB */
static struct fifo_cfg __initdata mode_1_cfg[] = {
{ .hw_ep_num = 1, .style = FIFO_TX,   .maxpacket = 512, .mode = BUF_DOUBLE, },
{ .hw_ep_num = 1, .style = FIFO_RX,   .maxpacket = 512, .mode = BUF_DOUBLE, },
{ .hw_ep_num = 2, .style = FIFO_RXTX, .maxpacket = 512, .mode = BUF_DOUBLE, },
{ .hw_ep_num = 3, .style = FIFO_RXTX, .maxpacket = 256, },
{ .hw_ep_num = 4, .style = FIFO_RXTX, .maxpacket = 256, },
};

/* mode 2 - fits in 4KB */
static struct fifo_cfg __initdata mode_2_cfg[] = {
{ .hw_ep_num = 1, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num = 1, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num = 2, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num = 2, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num = 3, .style = FIFO_RXTX, .maxpacket = 256, },
{ .hw_ep_num = 4, .style = FIFO_RXTX, .maxpacket = 256, },
};

/* mode 3 - fits in 4KB */
static struct fifo_cfg __initdata mode_3_cfg[] = {
{ .hw_ep_num = 1, .style = FIFO_TX,   .maxpacket = 512, .mode = BUF_DOUBLE, },
{ .hw_ep_num = 1, .style = FIFO_RX,   .maxpacket = 512, .mode = BUF_DOUBLE, },
{ .hw_ep_num = 2, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num = 2, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num = 3, .style = FIFO_RXTX, .maxpacket = 256, },
{ .hw_ep_num = 4, .style = FIFO_RXTX, .maxpacket = 256, },
};

/* mode 4 - fits in 16KB */
static struct fifo_cfg __initdata mode_4_cfg[] = {
{ .hw_ep_num =  1, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  1, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  2, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  2, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  3, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  3, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  4, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  4, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  5, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  5, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  6, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  6, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  7, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  7, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  8, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  8, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  9, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  9, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num = 10, .style = FIFO_TX,   .maxpacket = 256, },
{ .hw_ep_num = 10, .style = FIFO_RX,   .maxpacket = 64, },
{ .hw_ep_num = 11, .style = FIFO_TX,   .maxpacket = 256, },
{ .hw_ep_num = 11, .style = FIFO_RX,   .maxpacket = 64, },
{ .hw_ep_num = 12, .style = FIFO_TX,   .maxpacket = 256, },
{ .hw_ep_num = 12, .style = FIFO_RX,   .maxpacket = 64, },
{ .hw_ep_num = 13, .style = FIFO_RXTX, .maxpacket = 4096, },
{ .hw_ep_num = 14, .style = FIFO_RXTX, .maxpacket = 1024, },
{ .hw_ep_num = 15, .style = FIFO_RXTX, .maxpacket = 1024, },
};

/* mode 5 - fits in 8KB */
static struct fifo_cfg __initdata mode_5_cfg[] = {
{ .hw_ep_num =  1, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  1, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  2, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  2, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  3, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  3, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  4, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  4, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  5, .style = FIFO_TX,   .maxpacket = 512, },
{ .hw_ep_num =  5, .style = FIFO_RX,   .maxpacket = 512, },
{ .hw_ep_num =  6, .style = FIFO_TX,   .maxpacket = 32, },
{ .hw_ep_num =  6, .style = FIFO_RX,   .maxpacket = 32, },
{ .hw_ep_num =  7, .style = FIFO_TX,   .maxpacket = 32, },
{ .hw_ep_num =  7, .style = FIFO_RX,   .maxpacket = 32, },
{ .hw_ep_num =  8, .style = FIFO_TX,   .maxpacket = 32, },
{ .hw_ep_num =  8, .style = FIFO_RX,   .maxpacket = 32, },
{ .hw_ep_num =  9, .style = FIFO_TX,   .maxpacket = 32, },
{ .hw_ep_num =  9, .style = FIFO_RX,   .maxpacket = 32, },
{ .hw_ep_num = 10, .style = FIFO_TX,   .maxpacket = 32, },
{ .hw_ep_num = 10, .style = FIFO_RX,   .maxpacket = 32, },
{ .hw_ep_num = 11, .style = FIFO_TX,   .maxpacket = 32, },
{ .hw_ep_num = 11, .style = FIFO_RX,   .maxpacket = 32, },
{ .hw_ep_num = 12, .style = FIFO_TX,   .maxpacket = 32, },
{ .hw_ep_num = 12, .style = FIFO_RX,   .maxpacket = 32, },
{ .hw_ep_num = 13, .style = FIFO_RXTX, .maxpacket = 512, },
{ .hw_ep_num = 14, .style = FIFO_RXTX, .maxpacket = 1024, },
{ .hw_ep_num = 15, .style = FIFO_RXTX, .maxpacket = 1024, },
};

/*
 * configure a fifo; for non-shared endpoints, this may be called
 * once for a tx fifo and once for an rx fifo.
 *
 * returns negative errno or offset for next fifo.
 */
static int __init
fifo_setup(struct musb *musb, struct musb_hw_ep  *hw_ep,
                const struct fifo_cfg *cfg, u16 offset)
{
        void __iomem    *mbase = musb->mregs;
        int     size = 0;
        u16     maxpacket = cfg->maxpacket;
        u16     c_off = offset >> 3;
        u8      c_size;

        /* expect hw_ep has already been zero-initialized */

        size = ffs(max(maxpacket, (u16) 8)) - 1;
        maxpacket = 1 << size;

        c_size = size - 3;
        if (cfg->mode == BUF_DOUBLE) {
                if ((offset + (maxpacket << 1)) >
                                (1 << (musb->config->ram_bits + 2)))
                        return -EMSGSIZE;
                c_size |= MUSB_FIFOSZ_DPB;
        } else {
                if ((offset + maxpacket) > (1 << (musb->config->ram_bits + 2)))
                        return -EMSGSIZE;
        }

        /* configure the FIFO */
        musb_writeb(mbase, MUSB_INDEX, hw_ep->epnum);

#ifdef CONFIG_USB_MUSB_HDRC_HCD
        /* EP0 reserved endpoint for control, bidirectional;
         * EP1 reserved for bulk, two unidirection halves.
         */
        if (hw_ep->epnum == 1)
                musb->bulk_ep = hw_ep;
        /* REVISIT error check:  be sure ep0 can both rx and tx ... */
#endif
        switch (cfg->style) {
        case FIFO_TX:
                musb_write_txfifosz(mbase, c_size);
                musb_write_txfifoadd(mbase, c_off);
                hw_ep->tx_double_buffered = !!(c_size & MUSB_FIFOSZ_DPB);
                hw_ep->max_packet_sz_tx = maxpacket;
                break;
        case FIFO_RX:
                musb_write_rxfifosz(mbase, c_size);
                musb_write_rxfifoadd(mbase, c_off);
                hw_ep->rx_double_buffered = !!(c_size & MUSB_FIFOSZ_DPB);
                hw_ep->max_packet_sz_rx = maxpacket;
                break;
        case FIFO_RXTX:
                musb_write_txfifosz(mbase, c_size);
                musb_write_txfifoadd(mbase, c_off);
                hw_ep->rx_double_buffered = !!(c_size & MUSB_FIFOSZ_DPB);
                hw_ep->max_packet_sz_rx = maxpacket;

                musb_write_rxfifosz(mbase, c_size);
                musb_write_rxfifoadd(mbase, c_off);
                hw_ep->tx_double_buffered = hw_ep->rx_double_buffered;
                hw_ep->max_packet_sz_tx = maxpacket;

                hw_ep->is_shared_fifo = true;
                break;
        }

        /* NOTE rx and tx endpoint irqs aren't managed separately,
         * which happens to be ok
         */
        musb->epmask |= (1 << hw_ep->epnum);

        return offset + (maxpacket << ((c_size & MUSB_FIFOSZ_DPB) ? 1 : 0));
}

static struct fifo_cfg __initdata ep0_cfg = {
        .style = FIFO_RXTX, .maxpacket = 64,
};

static int __init ep_config_from_table(struct musb *musb)
{
        const struct fifo_cfg   *cfg;
        unsigned                i, n;
        int                     offset;
        struct musb_hw_ep       *hw_ep = musb->endpoints;

        switch (fifo_mode) {
        default:
                fifo_mode = 0;
                /* FALLTHROUGH */
        case 0:
                cfg = mode_0_cfg;
                n = ARRAY_SIZE(mode_0_cfg);
                break;
        case 1:
                cfg = mode_1_cfg;
                n = ARRAY_SIZE(mode_1_cfg);
                break;
        case 2:
                cfg = mode_2_cfg;
                n = ARRAY_SIZE(mode_2_cfg);
                break;
        case 3:
                cfg = mode_3_cfg;
                n = ARRAY_SIZE(mode_3_cfg);
                break;
        case 4:
                cfg = mode_4_cfg;
                n = ARRAY_SIZE(mode_4_cfg);
                break;
        case 5:
                cfg = mode_5_cfg;
                n = ARRAY_SIZE(mode_5_cfg);
                break;
        }

        printk(KERN_DEBUG "%s: setup fifo_mode %d\n",
                        musb_driver_name, fifo_mode);


        offset = fifo_setup(musb, hw_ep, &ep0_cfg, 0);
        /* assert(offset > 0) */

        /* NOTE:  for RTL versions >= 1.400 EPINFO and RAMINFO would
         * be better than static musb->config->num_eps and DYN_FIFO_SIZE...
         */

        for (i = 0; i < n; i++) {
                u8      epn = cfg->hw_ep_num;

                if (epn >= musb->config->num_eps) {
                        pr_debug("%s: invalid ep %d\n",
                                        musb_driver_name, epn);
                        return -EINVAL;
                }
                offset = fifo_setup(musb, hw_ep + epn, cfg++, offset);
                if (offset < 0) {
                        pr_debug("%s: mem overrun, ep %d\n",
                                        musb_driver_name, epn);
                        return -EINVAL;
                }
                epn++;
                musb->nr_endpoints = max(epn, musb->nr_endpoints);
        }

        printk(KERN_DEBUG "%s: %d/%d max ep, %d/%d memory\n",
                        musb_driver_name,
                        n + 1, musb->config->num_eps * 2 - 1,
                        offset, (1 << (musb->config->ram_bits + 2)));

#ifdef CONFIG_USB_MUSB_HDRC_HCD
        if (!musb->bulk_ep) {
                pr_debug("%s: missing bulk\n", musb_driver_name);
                return -EINVAL;
        }
#endif

        return 0;
}


/*
 * ep_config_from_hw - when MUSB_C_DYNFIFO_DEF is false
 * @param musb the controller
 */
static int __init ep_config_from_hw(struct musb *musb)
{
        u8 epnum = 0;
        struct musb_hw_ep *hw_ep;
        void *mbase = musb->mregs;
        int ret = 0;

        DBG(2, "<== static silicon ep config\n");

        /* FIXME pick up ep0 maxpacket size */

        for (epnum = 1; epnum < musb->config->num_eps; epnum++) {
                musb_ep_select(mbase, epnum);
                hw_ep = musb->endpoints + epnum;

                ret = musb_read_fifosize(musb, hw_ep, epnum);
                if (ret < 0)
                        break;

                /* FIXME set up hw_ep->{rx,tx}_double_buffered */

#ifdef CONFIG_USB_MUSB_HDRC_HCD
                /* pick an RX/TX endpoint for bulk */
                if (hw_ep->max_packet_sz_tx < 512
                                || hw_ep->max_packet_sz_rx < 512)
                        continue;

                /* REVISIT:  this algorithm is lazy, we should at least
                 * try to pick a double buffered endpoint.
                 */
                if (musb->bulk_ep)
                        continue;
                musb->bulk_ep = hw_ep;
#endif
        }

#ifdef CONFIG_USB_MUSB_HDRC_HCD
        if (!musb->bulk_ep) {
                pr_debug("%s: missing bulk\n", musb_driver_name);
                return -EINVAL;
        }
#endif

        return 0;
}

enum { MUSB_CONTROLLER_MHDRC, MUSB_CONTROLLER_HDRC, };

/* Initialize MUSB (M)HDRC part of the USB hardware subsystem;
 * configure endpoints, or take their config from silicon
 */
static int __init musb_core_init(u16 musb_type, struct musb *musb)
{
        u8 reg;
        char *type;
        char aInfo[90], aRevision[32], aDate[12];
        void __iomem    *mbase = musb->mregs;
        int             status = 0;
        int             i;

        /* log core options (read using indexed model) */
        reg = musb_read_configdata(mbase);

        strcpy(aInfo, (reg & MUSB_CONFIGDATA_UTMIDW) ? "UTMI-16" : "UTMI-8");
        if (reg & MUSB_CONFIGDATA_DYNFIFO) {
                strcat(aInfo, ", dyn FIFOs");
                musb->dyn_fifo = true;
        }
        if (reg & MUSB_CONFIGDATA_MPRXE) {
                strcat(aInfo, ", bulk combine");
                musb->bulk_combine = true;
        }
        if (reg & MUSB_CONFIGDATA_MPTXE) {
                strcat(aInfo, ", bulk split");
                musb->bulk_split = true;
        }
        if (reg & MUSB_CONFIGDATA_HBRXE) {
                strcat(aInfo, ", HB-ISO Rx");
                musb->hb_iso_rx = true;
        }
        if (reg & MUSB_CONFIGDATA_HBTXE) {
                strcat(aInfo, ", HB-ISO Tx");
                musb->hb_iso_tx = true;
        }
        if (reg & MUSB_CONFIGDATA_SOFTCONE)
                strcat(aInfo, ", SoftConn");

        printk(KERN_DEBUG "%s: ConfigData=0x%02x (%s)\n",
                        musb_driver_name, reg, aInfo);

        aDate[0] = 0;
        if (MUSB_CONTROLLER_MHDRC == musb_type) {
                musb->is_multipoint = 1;
                type = "M";
        } else {
                musb->is_multipoint = 0;
                type = "";
#ifdef CONFIG_USB_MUSB_HDRC_HCD
#ifndef CONFIG_USB_OTG_BLACKLIST_HUB
                printk(KERN_ERR
                        "%s: kernel must blacklist external hubs\n",
                        musb_driver_name);
#endif
#endif
        }

        /* log release info */
        musb->hwvers = musb_read_hwvers(mbase);
        snprintf(aRevision, 32, "%d.%d%s", MUSB_HWVERS_MAJOR(musb->hwvers),
                MUSB_HWVERS_MINOR(musb->hwvers),
                (musb->hwvers & MUSB_HWVERS_RC) ? "RC" : "");
        printk(KERN_DEBUG "%s: %sHDRC RTL version %s %s\n",
                        musb_driver_name, type, aRevision, aDate);

        /* configure ep0 */
        musb_configure_ep0(musb);

        /* discover endpoint configuration */
        musb->nr_endpoints = 1;
        musb->epmask = 1;

        if (musb->dyn_fifo)
                status = ep_config_from_table(musb);
        else
                status = ep_config_from_hw(musb);

        if (status < 0)
                return status;

        /* finish init, and print endpoint config */
        for (i = 0; i < musb->nr_endpoints; i++) {
                struct musb_hw_ep       *hw_ep = musb->endpoints + i;

                hw_ep->fifo = MUSB_FIFO_OFFSET(i) + mbase;
#ifdef CONFIG_USB_TUSB6010
                hw_ep->fifo_async = musb->async + 0x400 + MUSB_FIFO_OFFSET(i);
                hw_ep->fifo_sync = musb->sync + 0x400 + MUSB_FIFO_OFFSET(i);
                hw_ep->fifo_sync_va =
                        musb->sync_va + 0x400 + MUSB_FIFO_OFFSET(i);

                if (i == 0)
                        hw_ep->conf = mbase - 0x400 + TUSB_EP0_CONF;
                else
                        hw_ep->conf = mbase + 0x400 + (((i - 1) & 0xf) << 2);
#endif

                hw_ep->regs = MUSB_EP_OFFSET(i, 0) + mbase;
#ifdef CONFIG_USB_MUSB_HDRC_HCD
                hw_ep->target_regs = musb_read_target_reg_base(i, mbase);
                hw_ep->rx_reinit = 1;
                hw_ep->tx_reinit = 1;
#endif

                if (hw_ep->max_packet_sz_tx) {
                        DBG(1,
                                "%s: hw_ep %d%s, %smax %d\n",
                                musb_driver_name, i,
                                hw_ep->is_shared_fifo ? "shared" : "tx",
                                hw_ep->tx_double_buffered
                                        ? "doublebuffer, " : "",
                                hw_ep->max_packet_sz_tx);
                }
                if (hw_ep->max_packet_sz_rx && !hw_ep->is_shared_fifo) {
                        DBG(1,
                                "%s: hw_ep %d%s, %smax %d\n",
                                musb_driver_name, i,
                                "rx",
                                hw_ep->rx_double_buffered
                                        ? "doublebuffer, " : "",
                                hw_ep->max_packet_sz_rx);
                }
                if (!(hw_ep->max_packet_sz_tx || hw_ep->max_packet_sz_rx))
                        DBG(1, "hw_ep %d not configured\n", i);
        }

        return 0;
}

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

#if defined(CONFIG_ARCH_OMAP2430) || defined(CONFIG_ARCH_OMAP3430)

static irqreturn_t generic_interrupt(int irq, void *__hci)
{
        unsigned long   flags;
        irqreturn_t     retval = IRQ_NONE;
        struct musb     *musb = __hci;

        spin_lock_irqsave(&musb->lock, flags);

        musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
        musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
        musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);

        if (musb->int_usb || musb->int_tx || musb->int_rx)
                retval = musb_interrupt(musb);

        spin_unlock_irqrestore(&musb->lock, flags);

        return retval;
}

#else
#define generic_interrupt       NULL
#endif

/*
 * handle all the irqs defined by the HDRC core. for now we expect:  other
 * irq sources (phy, dma, etc) will be handled first, musb->int_* values
 * will be assigned, and the irq will already have been acked.
 *
 * called in irq context with spinlock held, irqs blocked
 */
irqreturn_t musb_interrupt(struct musb *musb)
{
        irqreturn_t     retval = IRQ_NONE;
        u8              devctl, power;
        int             ep_num;
        u32             reg;

        devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
        power = musb_readb(musb->mregs, MUSB_POWER);

        DBG(4, "** IRQ %s usb%04x tx%04x rx%04x\n",
                (devctl & MUSB_DEVCTL_HM) ? "host" : "peripheral",
                musb->int_usb, musb->int_tx, musb->int_rx);

#ifdef CONFIG_USB_GADGET_MUSB_HDRC
        if (is_otg_enabled(musb) || is_peripheral_enabled(musb))
                if (!musb->gadget_driver) {
                        DBG(5, "No gadget driver loaded\n");
                        return IRQ_HANDLED;
                }
#endif

        /* the core can interrupt us for multiple reasons; docs have
         * a generic interrupt flowchart to follow
         */
        if (musb->int_usb & STAGE0_MASK)
                retval |= musb_stage0_irq(musb, musb->int_usb,
                                devctl, power);

        /* "stage 1" is handling endpoint irqs */

        /* handle endpoint 0 first */
        if (musb->int_tx & 1) {
                if (devctl & MUSB_DEVCTL_HM)
                        retval |= musb_h_ep0_irq(musb);
                else
                        retval |= musb_g_ep0_irq(musb);
        }

        /* RX on endpoints 1-15 */
        reg = musb->int_rx >> 1;
        ep_num = 1;
        while (reg) {
                if (reg & 1) {
                        /* musb_ep_select(musb->mregs, ep_num); */
                        /* REVISIT just retval = ep->rx_irq(...) */
                        retval = IRQ_HANDLED;
                        if (devctl & MUSB_DEVCTL_HM) {
                                if (is_host_capable())
                                        musb_host_rx(musb, ep_num);
                        } else {
                                if (is_peripheral_capable())
                                        musb_g_rx(musb, ep_num);
                        }
                }

                reg >>= 1;
                ep_num++;
        }

        /* TX on endpoints 1-15 */
        reg = musb->int_tx >> 1;
        ep_num = 1;
        while (reg) {
                if (reg & 1) {
                        /* musb_ep_select(musb->mregs, ep_num); */
                        /* REVISIT just retval |= ep->tx_irq(...) */
                        retval = IRQ_HANDLED;
                        if (devctl & MUSB_DEVCTL_HM) {
                                if (is_host_capable())
                                        musb_host_tx(musb, ep_num);
                        } else {
                                if (is_peripheral_capable())
                                        musb_g_tx(musb, ep_num);
                        }
                }
                reg >>= 1;
                ep_num++;
        }

        return retval;
}


#ifndef CONFIG_MUSB_PIO_ONLY
static int __initdata use_dma = 1;

/* "modprobe ... use_dma=0" etc */
module_param(use_dma, bool, 0);
MODULE_PARM_DESC(use_dma, "enable/disable use of DMA");

void musb_dma_completion(struct musb *musb, u8 epnum, u8 transmit)
{
        u8      devctl = musb_readb(musb->mregs, MUSB_DEVCTL);

        /* called with controller lock already held */

        if (!epnum) {
#ifndef CONFIG_USB_TUSB_OMAP_DMA
                if (!is_cppi_enabled()) {
                        /* endpoint 0 */
                        if (devctl & MUSB_DEVCTL_HM)
                                musb_h_ep0_irq(musb);
                        else
                                musb_g_ep0_irq(musb);
                }
#endif
        } else {
                /* endpoints 1..15 */
                if (transmit) {
                        if (devctl & MUSB_DEVCTL_HM) {
                                if (is_host_capable())
                                        musb_host_tx(musb, epnum);
                        } else {
                                if (is_peripheral_capable())
                                        musb_g_tx(musb, epnum);
                        }
                } else {
                        /* receive */
                        if (devctl & MUSB_DEVCTL_HM) {
                                if (is_host_capable())
                                        musb_host_rx(musb, epnum);
                        } else {
                                if (is_peripheral_capable())
                                        musb_g_rx(musb, epnum);
                        }
                }
        }
}

#else
#define use_dma                 0
#endif

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

#ifdef CONFIG_SYSFS

static ssize_t
musb_mode_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct musb *musb = dev_to_musb(dev);
        unsigned long flags;
        int ret = -EINVAL;

        spin_lock_irqsave(&musb->lock, flags);
        ret = sprintf(buf, "%s\n", otg_state_string(musb));
        spin_unlock_irqrestore(&musb->lock, flags);

        return ret;
}

static ssize_t
musb_mode_store(struct device *dev, struct device_attribute *attr,
                const char *buf, size_t n)
{
        struct musb     *musb = dev_to_musb(dev);
        unsigned long   flags;
        int             status;

        spin_lock_irqsave(&musb->lock, flags);
        if (sysfs_streq(buf, "host"))
                status = musb_platform_set_mode(musb, MUSB_HOST);
        else if (sysfs_streq(buf, "peripheral"))
                status = musb_platform_set_mode(musb, MUSB_PERIPHERAL);
        else if (sysfs_streq(buf, "otg"))
                status = musb_platform_set_mode(musb, MUSB_OTG);
        else
                status = -EINVAL;
        spin_unlock_irqrestore(&musb->lock, flags);

        return (status == 0) ? n : status;
}
static DEVICE_ATTR(mode, 0644, musb_mode_show, musb_mode_store);

static ssize_t
musb_vbus_store(struct device *dev, struct device_attribute *attr,
                const char *buf, size_t n)
{
        struct musb     *musb = dev_to_musb(dev);
        unsigned long   flags;
        unsigned long   val;

        if (sscanf(buf, "%lu", &val) < 1) {
                dev_err(dev, "Invalid VBUS timeout ms value\n");
                return -EINVAL;
        }

        spin_lock_irqsave(&musb->lock, flags);
        /* force T(a_wait_bcon) to be zero/unlimited *OR* valid */
        musb->a_wait_bcon = val ? max_t(int, val, OTG_TIME_A_WAIT_BCON) : 0 ;
        if (musb->xceiv->state == OTG_STATE_A_WAIT_BCON)
                musb->is_active = 0;
        musb_platform_try_idle(musb, jiffies + msecs_to_jiffies(val));
        spin_unlock_irqrestore(&musb->lock, flags);

        return n;
}

static ssize_t
musb_vbus_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct musb     *musb = dev_to_musb(dev);
        unsigned long   flags;
        unsigned long   val;
        int             vbus;

        spin_lock_irqsave(&musb->lock, flags);
        val = musb->a_wait_bcon;
        /* FIXME get_vbus_status() is normally #defined as false...
         * and is effectively TUSB-specific.
         */
        vbus = musb_platform_get_vbus_status(musb);
        spin_unlock_irqrestore(&musb->lock, flags);

        return sprintf(buf, "Vbus %s, timeout %lu msec\n",
                        vbus ? "on" : "off", val);
}
static DEVICE_ATTR(vbus, 0644, musb_vbus_show, musb_vbus_store);

#ifdef CONFIG_USB_GADGET_MUSB_HDRC

/* Gadget drivers can't know that a host is connected so they might want
 * to start SRP, but users can.  This allows userspace to trigger SRP.
 */
static ssize_t
musb_srp_store(struct device *dev, struct device_attribute *attr,
                const char *buf, size_t n)
{
        struct musb     *musb = dev_to_musb(dev);
        unsigned short  srp;

        if (sscanf(buf, "%hu", &srp) != 1
                        || (srp != 1)) {
                dev_err(dev, "SRP: Value must be 1\n");
                return -EINVAL;
        }

        if (srp == 1)
                musb_g_wakeup(musb);

        return n;
}
static DEVICE_ATTR(srp, 0644, NULL, musb_srp_store);

#endif /* CONFIG_USB_GADGET_MUSB_HDRC */

static struct attribute *musb_attributes[] = {
        &dev_attr_mode.attr,
        &dev_attr_vbus.attr,
#ifdef CONFIG_USB_GADGET_MUSB_HDRC
        &dev_attr_srp.attr,
#endif
        NULL
};

static const struct attribute_group musb_attr_group = {
        .attrs = musb_attributes,
};

#endif  /* sysfs */

/* Only used to provide driver mode change events */
static void musb_irq_work(struct work_struct *data)
{
        struct musb *musb = container_of(data, struct musb, irq_work);
        static int old_state;

        if (musb->xceiv->state != old_state) {
                old_state = musb->xceiv->state;
                sysfs_notify(&musb->controller->kobj, NULL, "mode");
        }
}

/* --------------------------------------------------------------------------
 * Init support
 */

static struct musb *__init
allocate_instance(struct device *dev,
                struct musb_hdrc_config *config, void __iomem *mbase)
{
        struct musb             *musb;
        struct musb_hw_ep       *ep;
        int                     epnum;
#ifdef CONFIG_USB_MUSB_HDRC_HCD
        struct usb_hcd  *hcd;

        hcd = usb_create_hcd(&musb_hc_driver, dev, dev_name(dev));
        if (!hcd)
                return NULL;
        /* usbcore sets dev->driver_data to hcd, and sometimes uses that... */

        musb = hcd_to_musb(hcd);
        INIT_LIST_HEAD(&musb->control);
        INIT_LIST_HEAD(&musb->in_bulk);
        INIT_LIST_HEAD(&musb->out_bulk);

        hcd->uses_new_polling = 1;

        musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
        musb->a_wait_bcon = OTG_TIME_A_WAIT_BCON;
#else
        musb = kzalloc(sizeof *musb, GFP_KERNEL);
        if (!musb)
                return NULL;
        dev_set_drvdata(dev, musb);

#endif

        musb->mregs = mbase;
        musb->ctrl_base = mbase;
        musb->nIrq = -ENODEV;
        musb->config = config;
        BUG_ON(musb->config->num_eps > MUSB_C_NUM_EPS);
        for (epnum = 0, ep = musb->endpoints;
                        epnum < musb->config->num_eps;
                        epnum++, ep++) {
                ep->musb = musb;
                ep->epnum = epnum;
        }

        musb->controller = dev;
        return musb;
}

static void musb_free(struct musb *musb)
{
        /* this has multiple entry modes. it handles fault cleanup after
         * probe(), where things may be partially set up, as well as rmmod
         * cleanup after everything's been de-activated.
         */

#ifdef CONFIG_SYSFS
        sysfs_remove_group(&musb->controller->kobj, &musb_attr_group);
#endif

#ifdef CONFIG_USB_GADGET_MUSB_HDRC
        musb_gadget_cleanup(musb);
#endif

        if (musb->nIrq >= 0) {
                if (musb->irq_wake)
                        disable_irq_wake(musb->nIrq);
                free_irq(musb->nIrq, musb);
        }
        if (is_dma_capable() && musb->dma_controller) {
                struct dma_controller   *c = musb->dma_controller;

                (void) c->stop(c);
                dma_controller_destroy(c);
        }

#ifdef CONFIG_USB_MUSB_OTG
        put_device(musb->xceiv->dev);
#endif

        musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
        musb_platform_exit(musb);
        musb_writeb(musb->mregs, MUSB_DEVCTL, 0);

#ifdef CONFIG_USB_MUSB_HDRC_HCD
        usb_put_hcd(musb_to_hcd(musb));
#else
        kfree(musb);
#endif
}

/*
 * Perform generic per-controller initialization.
 *
 * @pDevice: the controller (already clocked, etc)
 * @nIrq: irq
 * @mregs: virtual address of controller registers,
 *      not yet corrected for platform-specific offsets
 */
static int __init
musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl)
{
        int                     status;
        struct musb             *musb;
        struct musb_hdrc_platform_data *plat = dev->platform_data;

        /* The driver might handle more features than the board; OK.
         * Fail when the board needs a feature that's not enabled.
         */
        if (!plat) {
                dev_dbg(dev, "no platform_data?\n");
                return -ENODEV;
        }
        switch (plat->mode) {
        case MUSB_HOST:
#ifdef CONFIG_USB_MUSB_HDRC_HCD
                break;
#else
                goto bad_config;
#endif
        case MUSB_PERIPHERAL:
#ifdef CONFIG_USB_GADGET_MUSB_HDRC
                break;
#else
                goto bad_config;
#endif
        case MUSB_OTG:
#ifdef CONFIG_USB_MUSB_OTG
                break;
#else
bad_config:
#endif
        default:
                dev_err(dev, "incompatible Kconfig role setting\n");
                return -EINVAL;
        }

        /* allocate */
        musb = allocate_instance(dev, plat->config, ctrl);
        if (!musb)
                return -ENOMEM;

        spin_lock_init(&musb->lock);
        musb->board_mode = plat->mode;
        musb->board_set_power = plat->set_power;
        musb->set_clock = plat->set_clock;
        musb->min_power = plat->min_power;

        /* Clock usage is chip-specific ... functional clock (DaVinci,
         * OMAP2430), or PHY ref (some TUSB6010 boards).  All this core
         * code does is make sure a clock handle is available; platform
         * code manages it during start/stop and suspend/resume.
         */
        if (plat->clock) {
                musb->clock = clk_get(dev, plat->clock);
                if (IS_ERR(musb->clock)) {
                        status = PTR_ERR(musb->clock);
                        musb->clock = NULL;
                        goto fail;
                }
        }

        /* The musb_platform_init() call:
         *   - adjusts musb->mregs and musb->isr if needed,
         *   - may initialize an integrated tranceiver
         *   - initializes musb->xceiv, usually by otg_get_transceiver()
         *   - activates clocks.
         *   - stops powering VBUS
         *   - assigns musb->board_set_vbus if host mode is enabled
         *
         * There are various transciever configurations.  Blackfin,
         * DaVinci, TUSB60x0, and others integrate them.  OMAP3 uses
         * external/discrete ones in various flavors (twl4030 family,
         * isp1504, non-OTG, etc) mostly hooking up through ULPI.
         */
        musb->isr = generic_interrupt;
        status = musb_platform_init(musb);

        if (status < 0)
                goto fail;
        if (!musb->isr) {
                status = -ENODEV;
                goto fail2;
        }

#ifndef CONFIG_MUSB_PIO_ONLY
        if (use_dma && dev->dma_mask) {
                struct dma_controller   *c;

                c = dma_controller_create(musb, musb->mregs);
                musb->dma_controller = c;
                if (c)
                        (void) c->start(c);
        }
#endif
        /* ideally this would be abstracted in platform setup */
        if (!is_dma_capable() || !musb->dma_controller)
                dev->dma_mask = NULL;

        /* be sure interrupts are disabled before connecting ISR */
        musb_platform_disable(musb);
        musb_generic_disable(musb);

        /* setup musb parts of the core (especially endpoints) */
        status = musb_core_init(plat->config->multipoint
                        ? MUSB_CONTROLLER_MHDRC
                        : MUSB_CONTROLLER_HDRC, musb);
        if (status < 0)
                goto fail2;

#ifdef CONFIG_USB_MUSB_OTG
        setup_timer(&musb->otg_timer, musb_otg_timer_func, (unsigned long) musb);
#endif

        /* Init IRQ workqueue before request_irq */
        INIT_WORK(&musb->irq_work, musb_irq_work);

        /* attach to the IRQ */
        if (request_irq(nIrq, musb->isr, 0, dev_name(dev), musb)) {
                dev_err(dev, "request_irq %d failed!\n", nIrq);
                status = -ENODEV;
                goto fail2;
        }
        musb->nIrq = nIrq;
/* FIXME this handles wakeup irqs wrong */
        if (enable_irq_wake(nIrq) == 0) {
                musb->irq_wake = 1;
                device_init_wakeup(dev, 1);
        } else {
                musb->irq_wake = 0;
        }

        /* host side needs more setup */
        if (is_host_enabled(musb)) {
                struct usb_hcd  *hcd = musb_to_hcd(musb);

                otg_set_host(musb->xceiv, &hcd->self);

                if (is_otg_enabled(musb))
                        hcd->self.otg_port = 1;
                musb->xceiv->host = &hcd->self;
                hcd->power_budget = 2 * (plat->power ? : 250);

                /* program PHY to use external vBus if required */
                if (plat->extvbus) {
                        u8 busctl = musb_read_ulpi_buscontrol(musb->mregs);
                        busctl |= MUSB_ULPI_USE_EXTVBUS;
                        musb_write_ulpi_buscontrol(musb->mregs, busctl);
                }
        }

        /* For the host-only role, we can activate right away.
         * (We expect the ID pin to be forcibly grounded!!)
         * Otherwise, wait till the gadget driver hooks up.
         */
        if (!is_otg_enabled(musb) && is_host_enabled(musb)) {
                MUSB_HST_MODE(musb);
                musb->xceiv->default_a = 1;
                musb->xceiv->state = OTG_STATE_A_IDLE;

                status = usb_add_hcd(musb_to_hcd(musb), -1, 0);
                if (status)
                        goto fail;

                DBG(1, "%s mode, status %d, devctl %02x %c\n",
                        "HOST", status,
                        musb_readb(musb->mregs, MUSB_DEVCTL),
                        (musb_readb(musb->mregs, MUSB_DEVCTL)
                                        & MUSB_DEVCTL_BDEVICE
                                ? 'B' : 'A'));

        } else /* peripheral is enabled */ {
                MUSB_DEV_MODE(musb);
                musb->xceiv->default_a = 0;
                musb->xceiv->state = OTG_STATE_B_IDLE;

                status = musb_gadget_setup(musb);
                if (status)
                        goto fail;

                DBG(1, "%s mode, status %d, dev%02x\n",
                        is_otg_enabled(musb) ? "OTG" : "PERIPHERAL",
                        status,
                        musb_readb(musb->mregs, MUSB_DEVCTL));

        }

#ifdef CONFIG_SYSFS
        status = sysfs_create_group(&musb->controller->kobj, &musb_attr_group);
#endif
        if (status)
                goto fail2;

        dev_info(dev, "USB %s mode controller at %p using %s, IRQ %d\n",
                        ({char *s;
                         switch (musb->board_mode) {
                         case MUSB_HOST:                s = "Host"; break;
                         case MUSB_PERIPHERAL:  s = "Peripheral"; break;
                         default:               s = "OTG"; break;
                         }; s; }),
                        ctrl,
                        (is_dma_capable() && musb->dma_controller)
                        ? "DMA" : "PIO",
                        musb->nIrq);

        return 0;

fail2:
        musb_platform_exit(musb);
fail:
        dev_err(musb->controller,
                "musb_init_controller failed with status %d\n", status);

        if (musb->clock)
                clk_put(musb->clock);
        device_init_wakeup(dev, 0);
        musb_free(musb);

        return status;

}

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

/* all implementations (PCI bridge to FPGA, VLYNQ, etc) should just
 * bridge to a platform device; this driver then suffices.
 */

#ifndef CONFIG_MUSB_PIO_ONLY
static u64      *orig_dma_mask;
#endif

static int __init musb_probe(struct platform_device *pdev)
{
        struct device   *dev = &pdev->dev;
        int             irq = platform_get_irq(pdev, 0);
        int             status;
        struct resource *iomem;
        void __iomem    *base;

        iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!iomem || irq == 0)
                return -ENODEV;

        base = ioremap(iomem->start, resource_size(iomem));
        if (!base) {
                dev_err(dev, "ioremap failed\n");
                return -ENOMEM;
        }

#ifndef CONFIG_MUSB_PIO_ONLY
        /* clobbered by use_dma=n */
        orig_dma_mask = dev->dma_mask;
#endif

        status = musb_init_controller(dev, irq, base);
        if (status < 0)
                iounmap(base);

        return status;
}

static int __exit musb_remove(struct platform_device *pdev)
{
        struct musb     *musb = dev_to_musb(&pdev->dev);
        void __iomem    *ctrl_base = musb->ctrl_base;

        /* this gets called on rmmod.
         *  - Host mode: host may still be active
         *  - Peripheral mode: peripheral is deactivated (or never-activated)
         *  - OTG mode: both roles are deactivated (or never-activated)
         */
        musb_shutdown(pdev);
#ifdef CONFIG_USB_MUSB_HDRC_HCD
        if (musb->board_mode == MUSB_HOST)
                usb_remove_hcd(musb_to_hcd(musb));
#endif
        musb_free(musb);
        iounmap(ctrl_base);
        device_init_wakeup(&pdev->dev, 0);
#ifndef CONFIG_MUSB_PIO_ONLY
        pdev->dev.dma_mask = orig_dma_mask;
#endif
        return 0;
}

#ifdef  CONFIG_PM

static struct musb_context_registers musb_context;

void musb_save_context(struct musb *musb)
{
        int i;
        void __iomem *musb_base = musb->mregs;

        if (is_host_enabled(musb)) {
                musb_context.frame = musb_readw(musb_base, MUSB_FRAME);
                musb_context.testmode = musb_readb(musb_base, MUSB_TESTMODE);
                musb_context.busctl = musb_read_ulpi_buscontrol(musb->mregs);
        }
        musb_context.power = musb_readb(musb_base, MUSB_POWER);
        musb_context.intrtxe = musb_readw(musb_base, MUSB_INTRTXE);
        musb_context.intrrxe = musb_readw(musb_base, MUSB_INTRRXE);
        musb_context.intrusbe = musb_readb(musb_base, MUSB_INTRUSBE);
        musb_context.index = musb_readb(musb_base, MUSB_INDEX);
        musb_context.devctl = musb_readb(musb_base, MUSB_DEVCTL);

        for (i = 0; i < MUSB_C_NUM_EPS; ++i) {
                musb_writeb(musb_base, MUSB_INDEX, i);
                musb_context.index_regs[i].txmaxp =
                        musb_readw(musb_base, 0x10 + MUSB_TXMAXP);
                musb_context.index_regs[i].txcsr =
                        musb_readw(musb_base, 0x10 + MUSB_TXCSR);
                musb_context.index_regs[i].rxmaxp =
                        musb_readw(musb_base, 0x10 + MUSB_RXMAXP);
                musb_context.index_regs[i].rxcsr =
                        musb_readw(musb_base, 0x10 + MUSB_RXCSR);

                if (musb->dyn_fifo) {
                        musb_context.index_regs[i].txfifoadd =
                                        musb_read_txfifoadd(musb_base);
                        musb_context.index_regs[i].rxfifoadd =
                                        musb_read_rxfifoadd(musb_base);
                        musb_context.index_regs[i].txfifosz =
                                        musb_read_txfifosz(musb_base);
                        musb_context.index_regs[i].rxfifosz =
                                        musb_read_rxfifosz(musb_base);
                }
                if (is_host_enabled(musb)) {
                        musb_context.index_regs[i].txtype =
                                musb_readb(musb_base, 0x10 + MUSB_TXTYPE);
                        musb_context.index_regs[i].txinterval =
                                musb_readb(musb_base, 0x10 + MUSB_TXINTERVAL);
                        musb_context.index_regs[i].rxtype =
                                musb_readb(musb_base, 0x10 + MUSB_RXTYPE);
                        musb_context.index_regs[i].rxinterval =
                                musb_readb(musb_base, 0x10 + MUSB_RXINTERVAL);

                        musb_context.index_regs[i].txfunaddr =
                                musb_read_txfunaddr(musb_base, i);
                        musb_context.index_regs[i].txhubaddr =
                                musb_read_txhubaddr(musb_base, i);
                        musb_context.index_regs[i].txhubport =
                                musb_read_txhubport(musb_base, i);

                        musb_context.index_regs[i].rxfunaddr =
                                musb_read_rxfunaddr(musb_base, i);
                        musb_context.index_regs[i].rxhubaddr =
                                musb_read_rxhubaddr(musb_base, i);
                        musb_context.index_regs[i].rxhubport =
                                musb_read_rxhubport(musb_base, i);
                }
        }

        musb_writeb(musb_base, MUSB_INDEX, musb_context.index);

        musb_platform_save_context(musb, &musb_context);
}

void musb_restore_context(struct musb *musb)
{
        int i;
        void __iomem *musb_base = musb->mregs;
        void __iomem *ep_target_regs;

        musb_platform_restore_context(musb, &musb_context);

        if (is_host_enabled(musb)) {
                musb_writew(musb_base, MUSB_FRAME, musb_context.frame);
                musb_writeb(musb_base, MUSB_TESTMODE, musb_context.testmode);
                musb_write_ulpi_buscontrol(musb->mregs, musb_context.busctl);
        }
        musb_writeb(musb_base, MUSB_POWER, musb_context.power);
        musb_writew(musb_base, MUSB_INTRTXE, musb_context.intrtxe);
        musb_writew(musb_base, MUSB_INTRRXE, musb_context.intrrxe);
        musb_writeb(musb_base, MUSB_INTRUSBE, musb_context.intrusbe);
        musb_writeb(musb_base, MUSB_DEVCTL, musb_context.devctl);

        for (i = 0; i < MUSB_C_NUM_EPS; ++i) {
                musb_writeb(musb_base, MUSB_INDEX, i);
                musb_writew(musb_base, 0x10 + MUSB_TXMAXP,
                        musb_context.index_regs[i].txmaxp);
                musb_writew(musb_base, 0x10 + MUSB_TXCSR,
                        musb_context.index_regs[i].txcsr);
                musb_writew(musb_base, 0x10 + MUSB_RXMAXP,
                        musb_context.index_regs[i].rxmaxp);
                musb_writew(musb_base, 0x10 + MUSB_RXCSR,
                        musb_context.index_regs[i].rxcsr);

                if (musb->dyn_fifo) {
                        musb_write_txfifosz(musb_base,
                                musb_context.index_regs[i].txfifosz);
                        musb_write_rxfifosz(musb_base,
                                musb_context.index_regs[i].rxfifosz);
                        musb_write_txfifoadd(musb_base,
                                musb_context.index_regs[i].txfifoadd);
                        musb_write_rxfifoadd(musb_base,
                                musb_context.index_regs[i].rxfifoadd);
                }

                if (is_host_enabled(musb)) {
                        musb_writeb(musb_base, 0x10 + MUSB_TXTYPE,
                                musb_context.index_regs[i].txtype);
                        musb_writeb(musb_base, 0x10 + MUSB_TXINTERVAL,
                                musb_context.index_regs[i].txinterval);
                        musb_writeb(musb_base, 0x10 + MUSB_RXTYPE,
                                musb_context.index_regs[i].rxtype);
                        musb_writeb(musb_base, 0x10 + MUSB_RXINTERVAL,

                        musb_context.index_regs[i].rxinterval);
                        musb_write_txfunaddr(musb_base, i,
                                musb_context.index_regs[i].txfunaddr);
                        musb_write_txhubaddr(musb_base, i,
                                musb_context.index_regs[i].txhubaddr);
                        musb_write_txhubport(musb_base, i,
                                musb_context.index_regs[i].txhubport);

                        ep_target_regs =
                                musb_read_target_reg_base(i, musb_base);

                        musb_write_rxfunaddr(ep_target_regs,
                                musb_context.index_regs[i].rxfunaddr);
                        musb_write_rxhubaddr(ep_target_regs,
                                musb_context.index_regs[i].rxhubaddr);
                        musb_write_rxhubport(ep_target_regs,
                                musb_context.index_regs[i].rxhubport);
                }
        }

        musb_writeb(musb_base, MUSB_INDEX, musb_context.index);
}

static int musb_suspend(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        unsigned long   flags;
        struct musb     *musb = dev_to_musb(&pdev->dev);

        if (!musb->clock)
                return 0;

        spin_lock_irqsave(&musb->lock, flags);

        if (is_peripheral_active(musb)) {
                /* FIXME force disconnect unless we know USB will wake
                 * the system up quickly enough to respond ...
                 */
        } else if (is_host_active(musb)) {
                /* we know all the children are suspended; sometimes
                 * they will even be wakeup-enabled.
                 */
        }

        musb_save_context(musb);

        if (musb->set_clock)
                musb->set_clock(musb->clock, 0);
        else
                clk_disable(musb->clock);
        spin_unlock_irqrestore(&musb->lock, flags);
        return 0;
}

static int musb_resume_noirq(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct musb     *musb = dev_to_musb(&pdev->dev);

        if (!musb->clock)
                return 0;

        if (musb->set_clock)
                musb->set_clock(musb->clock, 1);
        else
                clk_enable(musb->clock);

        musb_restore_context(musb);

        /* for static cmos like DaVinci, register values were preserved
         * unless for some reason the whole soc powered down or the USB
         * module got reset through the PSC (vs just being disabled).
         */
        return 0;
}

static const struct dev_pm_ops musb_dev_pm_ops = {
        .suspend        = musb_suspend,
        .resume_noirq   = musb_resume_noirq,
};

#define MUSB_DEV_PM_OPS (&musb_dev_pm_ops)
#else
#define MUSB_DEV_PM_OPS NULL
#endif

static struct platform_driver musb_driver = {
        .driver = {
                .name           = (char *)musb_driver_name,
                .bus            = &platform_bus_type,
                .owner          = THIS_MODULE,
                .pm             = MUSB_DEV_PM_OPS,
        },
        .remove         = __exit_p(musb_remove),
        .shutdown       = musb_shutdown,
};

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

static int __init musb_init(void)
{
#ifdef CONFIG_USB_MUSB_HDRC_HCD
        if (usb_disabled())
                return 0;
#endif

        pr_info("%s: version " MUSB_VERSION ", "
#ifdef CONFIG_MUSB_PIO_ONLY
                "pio"
#elif defined(CONFIG_USB_TI_CPPI_DMA)
                "cppi-dma"
#elif defined(CONFIG_USB_INVENTRA_DMA)
                "musb-dma"
#elif defined(CONFIG_USB_TUSB_OMAP_DMA)
                "tusb-omap-dma"
#else
                "?dma?"
#endif
                ", "
#ifdef CONFIG_USB_MUSB_OTG
                "otg (peripheral+host)"
#elif defined(CONFIG_USB_GADGET_MUSB_HDRC)
                "peripheral"
#elif defined(CONFIG_USB_MUSB_HDRC_HCD)
                "host"
#endif
                ", debug=%d\n",
                musb_driver_name, musb_debug);
        return platform_driver_probe(&musb_driver, musb_probe);
}

/* make us init after usbcore and i2c (transceivers, regulators, etc)
 * and before usb gadget and host-side drivers start to register
 */
fs_initcall(musb_init);

static void __exit musb_cleanup(void)
{
        platform_driver_unregister(&musb_driver);
}
module_exit(musb_cleanup);