/*
 * Driver for the NXP ISP1760 chip
 *
 * However, the code might contain some bugs. What doesn't work for sure is:
 * - ISO
 * - OTG
 e The interrupt line is configured as active low, level.
 *
 * (c) 2007 Sebastian Siewior <bigeasy@linutronix.de>
 *
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/usb.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <asm/unaligned.h>

#include "../core/hcd.h"
#include "isp1760-hcd.h"

static struct kmem_cache *qtd_cachep;
static struct kmem_cache *qh_cachep;

struct isp1760_hcd {
        u32 hcs_params;
        spinlock_t              lock;
        struct inter_packet_info atl_ints[32];
        struct inter_packet_info int_ints[32];
        struct memory_chunk memory_pool[BLOCKS];

        /* periodic schedule support */
#define DEFAULT_I_TDPS          1024
        unsigned                periodic_size;
        unsigned                i_thresh;
        unsigned long           reset_done;
        unsigned long           next_statechange;
        unsigned int            devflags;
};

static inline struct isp1760_hcd *hcd_to_priv(struct usb_hcd *hcd)
{
        return (struct isp1760_hcd *) (hcd->hcd_priv);
}
static inline struct usb_hcd *priv_to_hcd(struct isp1760_hcd *priv)
{
        return container_of((void *) priv, struct usb_hcd, hcd_priv);
}

/* Section 2.2 Host Controller Capability Registers */
#define HC_LENGTH(p)            (((p)>>00)&0x00ff)      /* bits 7:0 */
#define HC_VERSION(p)           (((p)>>16)&0xffff)      /* bits 31:16 */
#define HCS_INDICATOR(p)        ((p)&(1 << 16)) /* true: has port indicators */
#define HCS_PPC(p)              ((p)&(1 << 4))  /* true: port power control */
#define HCS_N_PORTS(p)          (((p)>>0)&0xf)  /* bits 3:0, ports on HC */
#define HCC_ISOC_CACHE(p)       ((p)&(1 << 7))  /* true: can cache isoc frame */
#define HCC_ISOC_THRES(p)       (((p)>>4)&0x7)  /* bits 6:4, uframes cached */

/* Section 2.3 Host Controller Operational Registers */
#define CMD_LRESET      (1<<7)          /* partial reset (no ports, etc) */
#define CMD_RESET       (1<<1)          /* reset HC not bus */
#define CMD_RUN         (1<<0)          /* start/stop HC */
#define STS_PCD         (1<<2)          /* port change detect */
#define FLAG_CF         (1<<0)          /* true: we'll support "high speed" */

#define PORT_OWNER      (1<<13)         /* true: companion hc owns this port */
#define PORT_POWER      (1<<12)         /* true: has power (see PPC) */
#define PORT_USB11(x) (((x) & (3 << 10)) == (1 << 10))  /* USB 1.1 device */
#define PORT_RESET      (1<<8)          /* reset port */
#define PORT_SUSPEND    (1<<7)          /* suspend port */
#define PORT_RESUME     (1<<6)          /* resume it */
#define PORT_PE         (1<<2)          /* port enable */
#define PORT_CSC        (1<<1)          /* connect status change */
#define PORT_CONNECT    (1<<0)          /* device connected */
#define PORT_RWC_BITS   (PORT_CSC)

struct isp1760_qtd {
        struct isp1760_qtd *hw_next;
        u8 packet_type;
        u8 toggle;

        void *data_buffer;
        /* the rest is HCD-private */
        struct list_head qtd_list;
        struct urb *urb;
        size_t length;

        /* isp special*/
        u32 status;
#define URB_COMPLETE_NOTIFY     (1 << 0)
#define URB_ENQUEUED            (1 << 1)
#define URB_TYPE_ATL            (1 << 2)
#define URB_TYPE_INT            (1 << 3)
};

struct isp1760_qh {
        /* first part defined by EHCI spec */
        struct list_head qtd_list;
        struct isp1760_hcd *priv;

        /* periodic schedule info */
        unsigned short period;          /* polling interval */
        struct usb_device *dev;

        u32 toggle;
        u32 ping;
};

#define ehci_port_speed(priv, portsc) (1 << USB_PORT_FEAT_HIGHSPEED)

static unsigned int isp1760_readl(__u32 __iomem *regs)
{
        return readl(regs);
}

static void isp1760_writel(const unsigned int val, __u32 __iomem *regs)
{
        writel(val, regs);
}

/*
 * The next two copy via MMIO data to/from the device. memcpy_{to|from}io()
 * doesn't quite work because some people have to enforce 32-bit access
 */
static void priv_read_copy(struct isp1760_hcd *priv, u32 *src,
                __u32 __iomem *dst, u32 len)
{
        u32 val;
        u8 *buff8;

        if (!src) {
                printk(KERN_ERR "ERROR: buffer: %p len: %d\n", src, len);
                return;
        }

        while (len >= 4) {
                *src = __raw_readl(dst);
                len -= 4;
                src++;
                dst++;
        }

        if (!len)
                return;

        /* in case we have 3, 2 or 1 by left. The dst buffer may not be fully
         * allocated.
         */
        val = isp1760_readl(dst);

        buff8 = (u8 *)src;
        while (len) {

                *buff8 = val;
                val >>= 8;
                len--;
                buff8++;
        }
}

static void priv_write_copy(const struct isp1760_hcd *priv, const u32 *src,
                __u32 __iomem *dst, u32 len)
{
        while (len >= 4) {
                __raw_writel(*src, dst);
                len -= 4;
                src++;
                dst++;
        }

        if (!len)
                return;
        /* in case we have 3, 2 or 1 by left. The buffer is allocated and the
         * extra bytes should not be read by the HW
         */

        __raw_writel(*src, dst);
}

/* memory management of the 60kb on the chip from 0x1000 to 0xffff */
static void init_memory(struct isp1760_hcd *priv)
{
        int i;
        u32 payload;

        payload = 0x1000;
        for (i = 0; i < BLOCK_1_NUM; i++) {
                priv->memory_pool[i].start = payload;
                priv->memory_pool[i].size = BLOCK_1_SIZE;
                priv->memory_pool[i].free = 1;
                payload += priv->memory_pool[i].size;
        }


        for (i = BLOCK_1_NUM; i < BLOCK_1_NUM + BLOCK_2_NUM; i++) {
                priv->memory_pool[i].start = payload;
                priv->memory_pool[i].size = BLOCK_2_SIZE;
                priv->memory_pool[i].free = 1;
                payload += priv->memory_pool[i].size;
        }


        for (i = BLOCK_1_NUM + BLOCK_2_NUM; i < BLOCKS; i++) {
                priv->memory_pool[i].start = payload;
                priv->memory_pool[i].size = BLOCK_3_SIZE;
                priv->memory_pool[i].free = 1;
                payload += priv->memory_pool[i].size;
        }

        BUG_ON(payload - priv->memory_pool[i - 1].size > PAYLOAD_SIZE);
}

static u32 alloc_mem(struct isp1760_hcd *priv, u32 size)
{
        int i;

        if (!size)
                return ISP1760_NULL_POINTER;

        for (i = 0; i < BLOCKS; i++) {
                if (priv->memory_pool[i].size >= size &&
                                priv->memory_pool[i].free) {

                        priv->memory_pool[i].free = 0;
                        return priv->memory_pool[i].start;
                }
        }

        printk(KERN_ERR "ISP1760 MEM: can not allocate %d bytes of memory\n",
                        size);
        printk(KERN_ERR "Current memory map:\n");
        for (i = 0; i < BLOCKS; i++) {
                printk(KERN_ERR "Pool %2d size %4d status: %d\n",
                                i, priv->memory_pool[i].size,
                                priv->memory_pool[i].free);
        }
        /* XXX maybe -ENOMEM could be possible */
        BUG();
        return 0;
}

static void free_mem(struct isp1760_hcd *priv, u32 mem)
{
        int i;

        if (mem == ISP1760_NULL_POINTER)
                return;

        for (i = 0; i < BLOCKS; i++) {
                if (priv->memory_pool[i].start == mem) {

                        BUG_ON(priv->memory_pool[i].free);

                        priv->memory_pool[i].free = 1;
                        return ;
                }
        }

        printk(KERN_ERR "Trying to free not-here-allocated memory :%08x\n",
                        mem);
        BUG();
}

static void isp1760_init_regs(struct usb_hcd *hcd)
{
        isp1760_writel(0, hcd->regs + HC_BUFFER_STATUS_REG);
        isp1760_writel(NO_TRANSFER_ACTIVE, hcd->regs +
                        HC_ATL_PTD_SKIPMAP_REG);
        isp1760_writel(NO_TRANSFER_ACTIVE, hcd->regs +
                        HC_INT_PTD_SKIPMAP_REG);
        isp1760_writel(NO_TRANSFER_ACTIVE, hcd->regs +
                        HC_ISO_PTD_SKIPMAP_REG);

        isp1760_writel(~NO_TRANSFER_ACTIVE, hcd->regs +
                        HC_ATL_PTD_DONEMAP_REG);
        isp1760_writel(~NO_TRANSFER_ACTIVE, hcd->regs +
                        HC_INT_PTD_DONEMAP_REG);
        isp1760_writel(~NO_TRANSFER_ACTIVE, hcd->regs +
                        HC_ISO_PTD_DONEMAP_REG);
}

static int handshake(struct isp1760_hcd *priv, void __iomem *ptr,
                      u32 mask, u32 done, int usec)
{
        u32 result;

        do {
                result = isp1760_readl(ptr);
                if (result == ~0)
                        return -ENODEV;
                result &= mask;
                if (result == done)
                        return 0;
                udelay(1);
                usec--;
        } while (usec > 0);
        return -ETIMEDOUT;
}

/* reset a non-running (STS_HALT == 1) controller */
static int ehci_reset(struct isp1760_hcd *priv)
{
        int retval;
        struct usb_hcd *hcd = priv_to_hcd(priv);
        u32 command = isp1760_readl(hcd->regs + HC_USBCMD);

        command |= CMD_RESET;
        isp1760_writel(command, hcd->regs + HC_USBCMD);
        hcd->state = HC_STATE_HALT;
        priv->next_statechange = jiffies;
        retval = handshake(priv, hcd->regs + HC_USBCMD,
                            CMD_RESET, 0, 250 * 1000);
        return retval;
}

static void qh_destroy(struct isp1760_qh *qh)
{
        BUG_ON(!list_empty(&qh->qtd_list));
        kmem_cache_free(qh_cachep, qh);
}

static struct isp1760_qh *isp1760_qh_alloc(struct isp1760_hcd *priv,
                gfp_t flags)
{
        struct isp1760_qh *qh;

        qh = kmem_cache_zalloc(qh_cachep, flags);
        if (!qh)
                return qh;

        INIT_LIST_HEAD(&qh->qtd_list);
        qh->priv = priv;
        return qh;
}

/* magic numbers that can affect system performance */
#define EHCI_TUNE_CERR          3       /* 0-3 qtd retries; 0 == don't stop */
#define EHCI_TUNE_RL_HS         4       /* nak throttle; see 4.9 */
#define EHCI_TUNE_RL_TT         0
#define EHCI_TUNE_MULT_HS       1       /* 1-3 transactions/uframe; 4.10.3 */
#define EHCI_TUNE_MULT_TT       1
#define EHCI_TUNE_FLS           2       /* (small) 256 frame schedule */

/* one-time init, only for memory state */
static int priv_init(struct usb_hcd *hcd)
{
        struct isp1760_hcd              *priv = hcd_to_priv(hcd);
        u32                     hcc_params;

        spin_lock_init(&priv->lock);

        /*
         * hw default: 1K periodic list heads, one per frame.
         * periodic_size can shrink by USBCMD update if hcc_params allows.
         */
        priv->periodic_size = DEFAULT_I_TDPS;

        /* controllers may cache some of the periodic schedule ... */
        hcc_params = isp1760_readl(hcd->regs + HC_HCCPARAMS);
        /* full frame cache */
        if (HCC_ISOC_CACHE(hcc_params))
                priv->i_thresh = 8;
        else /* N microframes cached */
                priv->i_thresh = 2 + HCC_ISOC_THRES(hcc_params);

        return 0;
}

static int isp1760_hc_setup(struct usb_hcd *hcd)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        int result;
        u32 scratch, hwmode;

        /* Setup HW Mode Control: This assumes a level active-low interrupt */
        hwmode = HW_DATA_BUS_32BIT;

        if (priv->devflags & ISP1760_FLAG_BUS_WIDTH_16)
                hwmode &= ~HW_DATA_BUS_32BIT;
        if (priv->devflags & ISP1760_FLAG_ANALOG_OC)
                hwmode |= HW_ANA_DIGI_OC;
        if (priv->devflags & ISP1760_FLAG_DACK_POL_HIGH)
                hwmode |= HW_DACK_POL_HIGH;
        if (priv->devflags & ISP1760_FLAG_DREQ_POL_HIGH)
                hwmode |= HW_DREQ_POL_HIGH;
        if (priv->devflags & ISP1760_FLAG_INTR_POL_HIGH)
                hwmode |= HW_INTR_HIGH_ACT;
        if (priv->devflags & ISP1760_FLAG_INTR_EDGE_TRIG)
                hwmode |= HW_INTR_EDGE_TRIG;

        /*
         * We have to set this first in case we're in 16-bit mode.
         * Write it twice to ensure correct upper bits if switching
         * to 16-bit mode.
         */
        isp1760_writel(hwmode, hcd->regs + HC_HW_MODE_CTRL);
        isp1760_writel(hwmode, hcd->regs + HC_HW_MODE_CTRL);

        isp1760_writel(0xdeadbabe, hcd->regs + HC_SCRATCH_REG);
        /* Change bus pattern */
        scratch = isp1760_readl(hcd->regs + HC_CHIP_ID_REG);
        scratch = isp1760_readl(hcd->regs + HC_SCRATCH_REG);
        if (scratch != 0xdeadbabe) {
                printk(KERN_ERR "ISP1760: Scratch test failed.\n");
                return -ENODEV;
        }

        /* pre reset */
        isp1760_init_regs(hcd);

        /* reset */
        isp1760_writel(SW_RESET_RESET_ALL, hcd->regs + HC_RESET_REG);
        mdelay(100);

        isp1760_writel(SW_RESET_RESET_HC, hcd->regs + HC_RESET_REG);
        mdelay(100);

        result = ehci_reset(priv);
        if (result)
                return result;

        /* Step 11 passed */

        isp1760_info(priv, "bus width: %d, oc: %s\n",
                           (priv->devflags & ISP1760_FLAG_BUS_WIDTH_16) ?
                           16 : 32, (priv->devflags & ISP1760_FLAG_ANALOG_OC) ?
                           "analog" : "digital");

        /* ATL reset */
        isp1760_writel(hwmode | ALL_ATX_RESET, hcd->regs + HC_HW_MODE_CTRL);
        mdelay(10);
        isp1760_writel(hwmode, hcd->regs + HC_HW_MODE_CTRL);

        isp1760_writel(INTERRUPT_ENABLE_MASK, hcd->regs + HC_INTERRUPT_REG);
        isp1760_writel(INTERRUPT_ENABLE_MASK, hcd->regs + HC_INTERRUPT_ENABLE);

        /*
         * PORT 1 Control register of the ISP1760 is the OTG control
         * register on ISP1761. Since there is no OTG or device controller
         * support in this driver, we use port 1 as a "normal" USB host port on
         * both chips.
         */
        isp1760_writel(PORT1_POWER | PORT1_INIT2,
                       hcd->regs + HC_PORT1_CTRL);
        mdelay(10);

        priv->hcs_params = isp1760_readl(hcd->regs + HC_HCSPARAMS);

        return priv_init(hcd);
}

static void isp1760_init_maps(struct usb_hcd *hcd)
{
        /*set last maps, for iso its only 1, else 32 tds bitmap*/
        isp1760_writel(0x80000000, hcd->regs + HC_ATL_PTD_LASTPTD_REG);
        isp1760_writel(0x80000000, hcd->regs + HC_INT_PTD_LASTPTD_REG);
        isp1760_writel(0x00000001, hcd->regs + HC_ISO_PTD_LASTPTD_REG);
}

static void isp1760_enable_interrupts(struct usb_hcd *hcd)
{
        isp1760_writel(0, hcd->regs + HC_ATL_IRQ_MASK_AND_REG);
        isp1760_writel(0, hcd->regs + HC_ATL_IRQ_MASK_OR_REG);
        isp1760_writel(0, hcd->regs + HC_INT_IRQ_MASK_AND_REG);
        isp1760_writel(0, hcd->regs + HC_INT_IRQ_MASK_OR_REG);
        isp1760_writel(0, hcd->regs + HC_ISO_IRQ_MASK_AND_REG);
        isp1760_writel(0xffffffff, hcd->regs + HC_ISO_IRQ_MASK_OR_REG);
        /* step 23 passed */
}

static int isp1760_run(struct usb_hcd *hcd)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        int retval;
        u32 temp;
        u32 command;
        u32 chipid;

        hcd->uses_new_polling = 1;
        hcd->poll_rh = 0;

        hcd->state = HC_STATE_RUNNING;
        isp1760_enable_interrupts(hcd);
        temp = isp1760_readl(hcd->regs + HC_HW_MODE_CTRL);
        isp1760_writel(temp | HW_GLOBAL_INTR_EN, hcd->regs + HC_HW_MODE_CTRL);

        command = isp1760_readl(hcd->regs + HC_USBCMD);
        command &= ~(CMD_LRESET|CMD_RESET);
        command |= CMD_RUN;
        isp1760_writel(command, hcd->regs + HC_USBCMD);

        retval = handshake(priv, hcd->regs + HC_USBCMD, CMD_RUN, CMD_RUN,
                        250 * 1000);
        if (retval)
                return retval;

        /*
         * XXX
         * Spec says to write FLAG_CF as last config action, priv code grabs
         * the semaphore while doing so.
         */
        down_write(&ehci_cf_port_reset_rwsem);
        isp1760_writel(FLAG_CF, hcd->regs + HC_CONFIGFLAG);

        retval = handshake(priv, hcd->regs + HC_CONFIGFLAG, FLAG_CF, FLAG_CF,
                        250 * 1000);
        up_write(&ehci_cf_port_reset_rwsem);
        if (retval)
                return retval;

        chipid = isp1760_readl(hcd->regs + HC_CHIP_ID_REG);
        isp1760_info(priv, "USB ISP %04x HW rev. %d started\n", chipid & 0xffff,
                        chipid >> 16);

        /* PTD Register Init Part 2, Step 28 */
        /* enable INTs */
        isp1760_init_maps(hcd);

        /* GRR this is run-once init(), being done every time the HC starts.
         * So long as they're part of class devices, we can't do it init()
         * since the class device isn't created that early.
         */
        return 0;
}

static u32 base_to_chip(u32 base)
{
        return ((base - 0x400) >> 3);
}

static void transform_into_atl(struct isp1760_hcd *priv, struct isp1760_qh *qh,
                        struct isp1760_qtd *qtd, struct urb *urb,
                        u32 payload, struct ptd *ptd)
{
        u32 dw0;
        u32 dw1;
        u32 dw2;
        u32 dw3;
        u32 maxpacket;
        u32 multi;
        u32 pid_code;
        u32 rl = RL_COUNTER;
        u32 nak = NAK_COUNTER;

        /* according to 3.6.2, max packet len can not be > 0x400 */
        maxpacket = usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe));
        multi =  1 + ((maxpacket >> 11) & 0x3);
        maxpacket &= 0x7ff;

        /* DW0 */
        dw0 = PTD_VALID;
        dw0 |= PTD_LENGTH(qtd->length);
        dw0 |= PTD_MAXPACKET(maxpacket);
        dw0 |= PTD_ENDPOINT(usb_pipeendpoint(urb->pipe));
        dw1 = usb_pipeendpoint(urb->pipe) >> 1;

        /* DW1 */
        dw1 |= PTD_DEVICE_ADDR(usb_pipedevice(urb->pipe));

        pid_code = qtd->packet_type;
        dw1 |= PTD_PID_TOKEN(pid_code);

        if (usb_pipebulk(urb->pipe))
                dw1 |= PTD_TRANS_BULK;
        else if  (usb_pipeint(urb->pipe))
                dw1 |= PTD_TRANS_INT;

        if (urb->dev->speed != USB_SPEED_HIGH) {
                /* split transaction */

                dw1 |= PTD_TRANS_SPLIT;
                if (urb->dev->speed == USB_SPEED_LOW)
                        dw1 |= PTD_SE_USB_LOSPEED;

                dw1 |= PTD_PORT_NUM(urb->dev->ttport);
                dw1 |= PTD_HUB_NUM(urb->dev->tt->hub->devnum);

                /* SE bit for Split INT transfers */
                if (usb_pipeint(urb->pipe) &&
                                (urb->dev->speed == USB_SPEED_LOW))
                        dw1 |= 2 << 16;

                dw3 = 0;
                rl = 0;
                nak = 0;
        } else {
                dw0 |= PTD_MULTI(multi);
                if (usb_pipecontrol(urb->pipe) || usb_pipebulk(urb->pipe))
                        dw3 = qh->ping;
                else
                        dw3 = 0;
        }
        /* DW2 */
        dw2 = 0;
        dw2 |= PTD_DATA_START_ADDR(base_to_chip(payload));
        dw2 |= PTD_RL_CNT(rl);
        dw3 |= PTD_NAC_CNT(nak);

        /* DW3 */
        if (usb_pipecontrol(urb->pipe))
                dw3 |= PTD_DATA_TOGGLE(qtd->toggle);
        else
                dw3 |= qh->toggle;


        dw3 |= PTD_ACTIVE;
        /* Cerr */
        dw3 |= PTD_CERR(ERR_COUNTER);

        memset(ptd, 0, sizeof(*ptd));

        ptd->dw0 = cpu_to_le32(dw0);
        ptd->dw1 = cpu_to_le32(dw1);
        ptd->dw2 = cpu_to_le32(dw2);
        ptd->dw3 = cpu_to_le32(dw3);
}

static void transform_add_int(struct isp1760_hcd *priv, struct isp1760_qh *qh,
                        struct isp1760_qtd *qtd, struct urb *urb,
                        u32 payload, struct ptd *ptd)
{
        u32 maxpacket;
        u32 multi;
        u32 numberofusofs;
        u32 i;
        u32 usofmask, usof;
        u32 period;

        maxpacket = usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe));
        multi =  1 + ((maxpacket >> 11) & 0x3);
        maxpacket &= 0x7ff;
        /* length of the data per uframe */
        maxpacket = multi * maxpacket;

        numberofusofs = urb->transfer_buffer_length / maxpacket;
        if (urb->transfer_buffer_length % maxpacket)
                numberofusofs += 1;

        usofmask = 1;
        usof = 0;
        for (i = 0; i < numberofusofs; i++) {
                usof |= usofmask;
                usofmask <<= 1;
        }

        if (urb->dev->speed != USB_SPEED_HIGH) {
                /* split */
                ptd->dw5 = cpu_to_le32(0x1c);

                if (qh->period >= 32)
                        period = qh->period / 2;
                else
                        period = qh->period;

        } else {

                if (qh->period >= 8)
                        period = qh->period/8;
                else
                        period = qh->period;

                if (period >= 32)
                        period  = 16;

                if (qh->period >= 8) {
                        /* millisecond period */
                        period = (period << 3);
                } else {
                        /* usof based tranmsfers */
                        /* minimum 4 usofs */
                        usof = 0x11;
                }
        }

        ptd->dw2 |= cpu_to_le32(period);
        ptd->dw4 = cpu_to_le32(usof);
}

static void transform_into_int(struct isp1760_hcd *priv, struct isp1760_qh *qh,
                        struct isp1760_qtd *qtd, struct urb *urb,
                        u32 payload, struct ptd *ptd)
{
        transform_into_atl(priv, qh, qtd, urb, payload, ptd);
        transform_add_int(priv, qh, qtd, urb,  payload, ptd);
}

static int qtd_fill(struct isp1760_qtd *qtd, void *databuffer, size_t len,
                u32 token)
{
        int count;

        qtd->data_buffer = databuffer;
        qtd->packet_type = GET_QTD_TOKEN_TYPE(token);
        qtd->toggle = GET_DATA_TOGGLE(token);

        if (len > HC_ATL_PL_SIZE)
                count = HC_ATL_PL_SIZE;
        else
                count = len;

        qtd->length = count;
        return count;
}

static int check_error(struct ptd *ptd)
{
        int error = 0;
        u32 dw3;

        dw3 = le32_to_cpu(ptd->dw3);
        if (dw3 & DW3_HALT_BIT)
                error = -EPIPE;

        if (dw3 & DW3_ERROR_BIT) {
                printk(KERN_ERR "error bit is set in DW3\n");
                error = -EPIPE;
        }

        if (dw3 & DW3_QTD_ACTIVE) {
                printk(KERN_ERR "transfer active bit is set DW3\n");
                printk(KERN_ERR "nak counter: %d, rl: %d\n", (dw3 >> 19) & 0xf,
                                (le32_to_cpu(ptd->dw2) >> 25) & 0xf);
        }

        return error;
}

static void check_int_err_status(u32 dw4)
{
        u32 i;

        dw4 >>= 8;

        for (i = 0; i < 8; i++) {
                switch (dw4 & 0x7) {
                case INT_UNDERRUN:
                        printk(KERN_ERR "ERROR: under run , %d\n", i);
                        break;

                case INT_EXACT:
                        printk(KERN_ERR "ERROR: transaction error, %d\n", i);
                        break;

                case INT_BABBLE:
                        printk(KERN_ERR "ERROR: babble error, %d\n", i);
                        break;
                }
                dw4 >>= 3;
        }
}

static void enqueue_one_qtd(struct isp1760_qtd *qtd, struct isp1760_hcd *priv,
                u32 payload)
{
        u32 token;
        struct usb_hcd *hcd = priv_to_hcd(priv);

        token = qtd->packet_type;

        if (qtd->length && (qtd->length <= HC_ATL_PL_SIZE)) {
                switch (token) {
                case IN_PID:
                        break;
                case OUT_PID:
                case SETUP_PID:
                        priv_write_copy(priv, qtd->data_buffer,
                                        hcd->regs + payload,
                                        qtd->length);
                }
        }
}

static void enqueue_one_atl_qtd(u32 atl_regs, u32 payload,
                struct isp1760_hcd *priv, struct isp1760_qh *qh,
                struct urb *urb, u32 slot, struct isp1760_qtd *qtd)
{
        struct ptd ptd;
        struct usb_hcd *hcd = priv_to_hcd(priv);

        transform_into_atl(priv, qh, qtd, urb, payload, &ptd);
        priv_write_copy(priv, (u32 *)&ptd, hcd->regs + atl_regs, sizeof(ptd));
        enqueue_one_qtd(qtd, priv, payload);

        priv->atl_ints[slot].urb = urb;
        priv->atl_ints[slot].qh = qh;
        priv->atl_ints[slot].qtd = qtd;
        priv->atl_ints[slot].data_buffer = qtd->data_buffer;
        priv->atl_ints[slot].payload = payload;
        qtd->status |= URB_ENQUEUED | URB_TYPE_ATL;
        qtd->status |= slot << 16;
}

static void enqueue_one_int_qtd(u32 int_regs, u32 payload,
                struct isp1760_hcd *priv, struct isp1760_qh *qh,
                struct urb *urb, u32 slot,  struct isp1760_qtd *qtd)
{
        struct ptd ptd;
        struct usb_hcd *hcd = priv_to_hcd(priv);

        transform_into_int(priv, qh, qtd, urb, payload, &ptd);
        priv_write_copy(priv, (u32 *)&ptd, hcd->regs + int_regs, sizeof(ptd));
        enqueue_one_qtd(qtd, priv, payload);

        priv->int_ints[slot].urb = urb;
        priv->int_ints[slot].qh = qh;
        priv->int_ints[slot].qtd = qtd;
        priv->int_ints[slot].data_buffer = qtd->data_buffer;
        priv->int_ints[slot].payload = payload;
        qtd->status |= URB_ENQUEUED | URB_TYPE_INT;
        qtd->status |= slot << 16;
}

static void enqueue_an_ATL_packet(struct usb_hcd *hcd, struct isp1760_qh *qh,
                                  struct isp1760_qtd *qtd)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        u32 skip_map, or_map;
        u32 queue_entry;
        u32 slot;
        u32 atl_regs, payload;
        u32 buffstatus;

        /*
         * When this function is called from the interrupt handler to enqueue
         * a follow-up packet, the SKIP register gets written and read back
         * almost immediately. With ISP1761, this register requires a delay of
         * 195ns between a write and subsequent read (see section 15.1.1.3).
         */
        ndelay(195);
        skip_map = isp1760_readl(hcd->regs + HC_ATL_PTD_SKIPMAP_REG);

        BUG_ON(!skip_map);
        slot = __ffs(skip_map);
        queue_entry = 1 << slot;

        atl_regs = ATL_REGS_OFFSET + slot * sizeof(struct ptd);

        payload = alloc_mem(priv, qtd->length);

        enqueue_one_atl_qtd(atl_regs, payload, priv, qh, qtd->urb, slot, qtd);

        or_map = isp1760_readl(hcd->regs + HC_ATL_IRQ_MASK_OR_REG);
        or_map |= queue_entry;
        isp1760_writel(or_map, hcd->regs + HC_ATL_IRQ_MASK_OR_REG);

        skip_map &= ~queue_entry;
        isp1760_writel(skip_map, hcd->regs + HC_ATL_PTD_SKIPMAP_REG);

        buffstatus = isp1760_readl(hcd->regs + HC_BUFFER_STATUS_REG);
        buffstatus |= ATL_BUFFER;
        isp1760_writel(buffstatus, hcd->regs + HC_BUFFER_STATUS_REG);
}

static void enqueue_an_INT_packet(struct usb_hcd *hcd, struct isp1760_qh *qh,
                                  struct isp1760_qtd *qtd)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        u32 skip_map, or_map;
        u32 queue_entry;
        u32 slot;
        u32 int_regs, payload;
        u32 buffstatus;

        /*
         * When this function is called from the interrupt handler to enqueue
         * a follow-up packet, the SKIP register gets written and read back
         * almost immediately. With ISP1761, this register requires a delay of
         * 195ns between a write and subsequent read (see section 15.1.1.3).
         */
        ndelay(195);
        skip_map = isp1760_readl(hcd->regs + HC_INT_PTD_SKIPMAP_REG);

        BUG_ON(!skip_map);
        slot = __ffs(skip_map);
        queue_entry = 1 << slot;

        int_regs = INT_REGS_OFFSET + slot * sizeof(struct ptd);

        payload = alloc_mem(priv, qtd->length);

        enqueue_one_int_qtd(int_regs, payload, priv, qh, qtd->urb, slot, qtd);

        or_map = isp1760_readl(hcd->regs + HC_INT_IRQ_MASK_OR_REG);
        or_map |= queue_entry;
        isp1760_writel(or_map, hcd->regs + HC_INT_IRQ_MASK_OR_REG);

        skip_map &= ~queue_entry;
        isp1760_writel(skip_map, hcd->regs + HC_INT_PTD_SKIPMAP_REG);

        buffstatus = isp1760_readl(hcd->regs + HC_BUFFER_STATUS_REG);
        buffstatus |= INT_BUFFER;
        isp1760_writel(buffstatus, hcd->regs + HC_BUFFER_STATUS_REG);
}

static void isp1760_urb_done(struct isp1760_hcd *priv, struct urb *urb, int status)
__releases(priv->lock)
__acquires(priv->lock)
{
        if (!urb->unlinked) {
                if (status == -EINPROGRESS)
                        status = 0;
        }

        /* complete() can reenter this HCD */
        usb_hcd_unlink_urb_from_ep(priv_to_hcd(priv), urb);
        spin_unlock(&priv->lock);
        usb_hcd_giveback_urb(priv_to_hcd(priv), urb, status);
        spin_lock(&priv->lock);
}

static void isp1760_qtd_free(struct isp1760_qtd *qtd)
{
        kmem_cache_free(qtd_cachep, qtd);
}

static struct isp1760_qtd *clean_this_qtd(struct isp1760_qtd *qtd)
{
        struct isp1760_qtd *tmp_qtd;

        tmp_qtd = qtd->hw_next;
        list_del(&qtd->qtd_list);
        isp1760_qtd_free(qtd);
        return tmp_qtd;
}

/*
 * Remove this QTD from the QH list and free its memory. If this QTD
 * isn't the last one than remove also his successor(s).
 * Returns the QTD which is part of an new URB and should be enqueued.
 */
static struct isp1760_qtd *clean_up_qtdlist(struct isp1760_qtd *qtd)
{
        struct isp1760_qtd *tmp_qtd;
        int last_one;

        do {
                tmp_qtd = qtd->hw_next;
                last_one = qtd->status & URB_COMPLETE_NOTIFY;
                list_del(&qtd->qtd_list);
                isp1760_qtd_free(qtd);
                qtd = tmp_qtd;
        } while (!last_one && qtd);

        return qtd;
}

static void do_atl_int(struct usb_hcd *usb_hcd)
{
        struct isp1760_hcd *priv = hcd_to_priv(usb_hcd);
        u32 done_map, skip_map;
        struct ptd ptd;
        struct urb *urb = NULL;
        u32 atl_regs_base;
        u32 atl_regs;
        u32 queue_entry;
        u32 payload;
        u32 length;
        u32 or_map;
        u32 status = -EINVAL;
        int error;
        struct isp1760_qtd *qtd;
        struct isp1760_qh *qh;
        u32 rl;
        u32 nakcount;

        done_map = isp1760_readl(usb_hcd->regs +
                        HC_ATL_PTD_DONEMAP_REG);
        skip_map = isp1760_readl(usb_hcd->regs +
                        HC_ATL_PTD_SKIPMAP_REG);

        or_map = isp1760_readl(usb_hcd->regs + HC_ATL_IRQ_MASK_OR_REG);
        or_map &= ~done_map;
        isp1760_writel(or_map, usb_hcd->regs + HC_ATL_IRQ_MASK_OR_REG);

        atl_regs_base = ATL_REGS_OFFSET;
        while (done_map) {
                u32 dw1;
                u32 dw2;
                u32 dw3;

                status = 0;

                queue_entry = __ffs(done_map);
                done_map &= ~(1 << queue_entry);
                skip_map |= 1 << queue_entry;

                atl_regs = atl_regs_base + queue_entry * sizeof(struct ptd);

                urb = priv->atl_ints[queue_entry].urb;
                qtd = priv->atl_ints[queue_entry].qtd;
                qh = priv->atl_ints[queue_entry].qh;
                payload = priv->atl_ints[queue_entry].payload;

                if (!qh) {
                        printk(KERN_ERR "qh is 0\n");
                        continue;
                }

                isp1760_writel(atl_regs + ISP_BANK(0), usb_hcd->regs +
                                HC_MEMORY_REG);
                isp1760_writel(payload  + ISP_BANK(1), usb_hcd->regs +
                                HC_MEMORY_REG);
                /*
                 * write bank1 address twice to ensure the 90ns delay (time
                 * between BANK0 write and the priv_read_copy() call is at
                 * least 3*t_WHWL + 2*t_w11 = 3*25ns + 2*17ns = 109ns)
                 */
                isp1760_writel(payload  + ISP_BANK(1), usb_hcd->regs +
                                HC_MEMORY_REG);

                priv_read_copy(priv, (u32 *)&ptd, usb_hcd->regs + atl_regs +
                                ISP_BANK(0), sizeof(ptd));

                dw1 = le32_to_cpu(ptd.dw1);
                dw2 = le32_to_cpu(ptd.dw2);
                dw3 = le32_to_cpu(ptd.dw3);
                rl = (dw2 >> 25) & 0x0f;
                nakcount = (dw3 >> 19) & 0xf;

                /* Transfer Error, *but* active and no HALT -> reload */
                if ((dw3 & DW3_ERROR_BIT) && (dw3 & DW3_QTD_ACTIVE) &&
                                !(dw3 & DW3_HALT_BIT)) {

                        /* according to ppriv code, we have to
                         * reload this one if trasfered bytes != requested bytes
                         * else act like everything went smooth..
                         * XXX This just doesn't feel right and hasn't
                         * triggered so far.
                         */

                        length = PTD_XFERRED_LENGTH(dw3);
                        printk(KERN_ERR "Should reload now.... transfered %d "
                                        "of %zu\n", length, qtd->length);
                        BUG();
                }

                if (!nakcount && (dw3 & DW3_QTD_ACTIVE)) {
                        u32 buffstatus;

                        /*
                         * NAKs are handled in HW by the chip. Usually if the
                         * device is not able to send data fast enough.
                         * This happens mostly on slower hardware.
                         */
                        printk(KERN_NOTICE "Reloading ptd %p/%p... qh %p read: "
                                        "%d of %zu done: %08x cur: %08x\n", qtd,
                                        urb, qh, PTD_XFERRED_LENGTH(dw3),
                                        qtd->length, done_map,
                                        (1 << queue_entry));

                        /* RL counter = ERR counter */
                        dw3 &= ~(0xf << 19);
                        dw3 |= rl << 19;
                        dw3 &= ~(3 << (55 - 32));
                        dw3 |= ERR_COUNTER << (55 - 32);

                        /*
                         * It is not needed to write skip map back because it
                         * is unchanged. Just make sure that this entry is
                         * unskipped once it gets written to the HW.
                         */
                        skip_map &= ~(1 << queue_entry);
                        or_map = isp1760_readl(usb_hcd->regs +
                                        HC_ATL_IRQ_MASK_OR_REG);
                        or_map |= 1 << queue_entry;
                        isp1760_writel(or_map, usb_hcd->regs +
                                        HC_ATL_IRQ_MASK_OR_REG);

                        ptd.dw3 = cpu_to_le32(dw3);
                        priv_write_copy(priv, (u32 *)&ptd, usb_hcd->regs +
                                        atl_regs, sizeof(ptd));

                        ptd.dw0 |= cpu_to_le32(PTD_VALID);
                        priv_write_copy(priv, (u32 *)&ptd, usb_hcd->regs +
                                        atl_regs, sizeof(ptd));

                        buffstatus = isp1760_readl(usb_hcd->regs +
                                        HC_BUFFER_STATUS_REG);
                        buffstatus |= ATL_BUFFER;
                        isp1760_writel(buffstatus, usb_hcd->regs +
                                        HC_BUFFER_STATUS_REG);
                        continue;
                }

                error = check_error(&ptd);
                if (error) {
                        status = error;
                        priv->atl_ints[queue_entry].qh->toggle = 0;
                        priv->atl_ints[queue_entry].qh->ping = 0;
                        urb->status = -EPIPE;

#if 0
                        printk(KERN_ERR "Error in %s().\n", __func__);
                        printk(KERN_ERR "IN dw0: %08x dw1: %08x dw2: %08x "
                                        "dw3: %08x dw4: %08x dw5: %08x dw6: "
                                        "%08x dw7: %08x\n",
                                        ptd.dw0, ptd.dw1, ptd.dw2, ptd.dw3,
                                        ptd.dw4, ptd.dw5, ptd.dw6, ptd.dw7);
#endif
                } else {
                        if (usb_pipetype(urb->pipe) == PIPE_BULK) {
                                priv->atl_ints[queue_entry].qh->toggle = dw3 &
                                        (1 << 25);
                                priv->atl_ints[queue_entry].qh->ping = dw3 &
                                        (1 << 26);
                        }
                }

                length = PTD_XFERRED_LENGTH(dw3);
                if (length) {
                        switch (DW1_GET_PID(dw1)) {
                        case IN_PID:
                                priv_read_copy(priv,
                                        priv->atl_ints[queue_entry].data_buffer,
                                        usb_hcd->regs + payload + ISP_BANK(1),
                                        length);

                        case OUT_PID:

                                urb->actual_length += length;

                        case SETUP_PID:
                                break;
                        }
                }

                priv->atl_ints[queue_entry].data_buffer = NULL;
                priv->atl_ints[queue_entry].urb = NULL;
                priv->atl_ints[queue_entry].qtd = NULL;
                priv->atl_ints[queue_entry].qh = NULL;

                free_mem(priv, payload);

                isp1760_writel(skip_map, usb_hcd->regs +
                                HC_ATL_PTD_SKIPMAP_REG);

                if (urb->status == -EPIPE) {
                        /* HALT was received */

                        qtd = clean_up_qtdlist(qtd);
                        isp1760_urb_done(priv, urb, urb->status);

                } else if (usb_pipebulk(urb->pipe) && (length < qtd->length)) {
                        /* short BULK received */

                        if (urb->transfer_flags & URB_SHORT_NOT_OK) {
                                urb->status = -EREMOTEIO;
                                isp1760_dbg(priv, "short bulk, %d instead %zu "
                                        "with URB_SHORT_NOT_OK flag.\n",
                                        length, qtd->length);
                        }

                        if (urb->status == -EINPROGRESS)
                                urb->status = 0;

                        qtd = clean_up_qtdlist(qtd);

                        isp1760_urb_done(priv, urb, urb->status);

                } else if (qtd->status & URB_COMPLETE_NOTIFY) {
                        /* that was the last qtd of that URB */

                        if (urb->status == -EINPROGRESS)
                                urb->status = 0;

                        qtd = clean_this_qtd(qtd);
                        isp1760_urb_done(priv, urb, urb->status);

                } else {
                        /* next QTD of this URB */

                        qtd = clean_this_qtd(qtd);
                        BUG_ON(!qtd);
                }

                if (qtd)
                        enqueue_an_ATL_packet(usb_hcd, qh, qtd);

                skip_map = isp1760_readl(usb_hcd->regs +
                                HC_ATL_PTD_SKIPMAP_REG);
        }
}

static void do_intl_int(struct usb_hcd *usb_hcd)
{
        struct isp1760_hcd *priv = hcd_to_priv(usb_hcd);
        u32 done_map, skip_map;
        struct ptd ptd;
        struct urb *urb = NULL;
        u32 int_regs;
        u32 int_regs_base;
        u32 payload;
        u32 length;
        u32 or_map;
        int error;
        u32 queue_entry;
        struct isp1760_qtd *qtd;
        struct isp1760_qh *qh;

        done_map = isp1760_readl(usb_hcd->regs +
                        HC_INT_PTD_DONEMAP_REG);
        skip_map = isp1760_readl(usb_hcd->regs +
                        HC_INT_PTD_SKIPMAP_REG);

        or_map = isp1760_readl(usb_hcd->regs + HC_INT_IRQ_MASK_OR_REG);
        or_map &= ~done_map;
        isp1760_writel(or_map, usb_hcd->regs + HC_INT_IRQ_MASK_OR_REG);

        int_regs_base = INT_REGS_OFFSET;

        while (done_map) {
                u32 dw1;
                u32 dw3;

                queue_entry = __ffs(done_map);
                done_map &= ~(1 << queue_entry);
                skip_map |= 1 << queue_entry;

                int_regs = int_regs_base + queue_entry * sizeof(struct ptd);
                urb = priv->int_ints[queue_entry].urb;
                qtd = priv->int_ints[queue_entry].qtd;
                qh = priv->int_ints[queue_entry].qh;
                payload = priv->int_ints[queue_entry].payload;

                if (!qh) {
                        printk(KERN_ERR "(INT) qh is 0\n");
                        continue;
                }

                isp1760_writel(int_regs + ISP_BANK(0), usb_hcd->regs +
                                HC_MEMORY_REG);
                isp1760_writel(payload  + ISP_BANK(1), usb_hcd->regs +
                                HC_MEMORY_REG);
                /*
                 * write bank1 address twice to ensure the 90ns delay (time
                 * between BANK0 write and the priv_read_copy() call is at
                 * least 3*t_WHWL + 2*t_w11 = 3*25ns + 2*17ns = 92ns)
                 */
                isp1760_writel(payload  + ISP_BANK(1), usb_hcd->regs +
                                HC_MEMORY_REG);

                priv_read_copy(priv, (u32 *)&ptd, usb_hcd->regs + int_regs +
                                ISP_BANK(0), sizeof(ptd));
                dw1 = le32_to_cpu(ptd.dw1);
                dw3 = le32_to_cpu(ptd.dw3);
                check_int_err_status(le32_to_cpu(ptd.dw4));

                error = check_error(&ptd);
                if (error) {
#if 0
                        printk(KERN_ERR "Error in %s().\n", __func__);
                        printk(KERN_ERR "IN dw0: %08x dw1: %08x dw2: %08x "
                                        "dw3: %08x dw4: %08x dw5: %08x dw6: "
                                        "%08x dw7: %08x\n",
                                        ptd.dw0, ptd.dw1, ptd.dw2, ptd.dw3,
                                        ptd.dw4, ptd.dw5, ptd.dw6, ptd.dw7);
#endif
                        urb->status = -EPIPE;
                        priv->int_ints[queue_entry].qh->toggle = 0;
                        priv->int_ints[queue_entry].qh->ping = 0;

                } else {
                        priv->int_ints[queue_entry].qh->toggle =
                                dw3 & (1 << 25);
                        priv->int_ints[queue_entry].qh->ping = dw3 & (1 << 26);
                }

                if (urb->dev->speed != USB_SPEED_HIGH)
                        length = PTD_XFERRED_LENGTH_LO(dw3);
                else
                        length = PTD_XFERRED_LENGTH(dw3);

                if (length) {
                        switch (DW1_GET_PID(dw1)) {
                        case IN_PID:
                                priv_read_copy(priv,
                                        priv->int_ints[queue_entry].data_buffer,
                                        usb_hcd->regs + payload + ISP_BANK(1),
                                        length);
                        case OUT_PID:

                                urb->actual_length += length;

                        case SETUP_PID:
                                break;
                        }
                }

                priv->int_ints[queue_entry].data_buffer = NULL;
                priv->int_ints[queue_entry].urb = NULL;
                priv->int_ints[queue_entry].qtd = NULL;
                priv->int_ints[queue_entry].qh = NULL;

                isp1760_writel(skip_map, usb_hcd->regs +
                                HC_INT_PTD_SKIPMAP_REG);
                free_mem(priv, payload);

                if (urb->status == -EPIPE) {
                        /* HALT received */

                         qtd = clean_up_qtdlist(qtd);
                         isp1760_urb_done(priv, urb, urb->status);

                } else if (qtd->status & URB_COMPLETE_NOTIFY) {

                        if (urb->status == -EINPROGRESS)
                                urb->status = 0;

                        qtd = clean_this_qtd(qtd);
                        isp1760_urb_done(priv, urb, urb->status);

                } else {
                        /* next QTD of this URB */

                        qtd = clean_this_qtd(qtd);
                        BUG_ON(!qtd);
                }

                if (qtd)
                        enqueue_an_INT_packet(usb_hcd, qh, qtd);

                skip_map = isp1760_readl(usb_hcd->regs +
                                HC_INT_PTD_SKIPMAP_REG);
        }
}

#define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff)
static struct isp1760_qh *qh_make(struct isp1760_hcd *priv, struct urb *urb,
                gfp_t flags)
{
        struct isp1760_qh *qh;
        int is_input, type;

        qh = isp1760_qh_alloc(priv, flags);
        if (!qh)
                return qh;

        /*
         * init endpoint/device data for this QH
         */
        is_input = usb_pipein(urb->pipe);
        type = usb_pipetype(urb->pipe);

        if (type == PIPE_INTERRUPT) {

                if (urb->dev->speed == USB_SPEED_HIGH) {

                        qh->period = urb->interval >> 3;
                        if (qh->period == 0 && urb->interval != 1) {
                                /* NOTE interval 2 or 4 uframes could work.
                                 * But interval 1 scheduling is simpler, and
                                 * includes high bandwidth.
                                 */
                                printk(KERN_ERR "intr period %d uframes, NYET!",
                                                urb->interval);
                                qh_destroy(qh);
                                return NULL;
                        }
                } else {
                        qh->period = urb->interval;
                }
        }

        /* support for tt scheduling, and access to toggles */
        qh->dev = urb->dev;

        if (!usb_pipecontrol(urb->pipe))
                usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe), !is_input,
                                1);
        return qh;
}

/*
 * For control/bulk/interrupt, return QH with these TDs appended.
 * Allocates and initializes the QH if necessary.
 * Returns null if it can't allocate a QH it needs to.
 * If the QH has TDs (urbs) already, that's great.
 */
static struct isp1760_qh *qh_append_tds(struct isp1760_hcd *priv,
                struct urb *urb, struct list_head *qtd_list, int epnum,
                void **ptr)
{
        struct isp1760_qh *qh;
        struct isp1760_qtd *qtd;
        struct isp1760_qtd *prev_qtd;

        qh = (struct isp1760_qh *)*ptr;
        if (!qh) {
                /* can't sleep here, we have priv->lock... */
                qh = qh_make(priv, urb, GFP_ATOMIC);
                if (!qh)
                        return qh;
                *ptr = qh;
        }

        qtd = list_entry(qtd_list->next, struct isp1760_qtd,
                        qtd_list);
        if (!list_empty(&qh->qtd_list))
                prev_qtd = list_entry(qh->qtd_list.prev,
                                struct isp1760_qtd, qtd_list);
        else
                prev_qtd = NULL;

        list_splice(qtd_list, qh->qtd_list.prev);
        if (prev_qtd) {
                BUG_ON(prev_qtd->hw_next);
                prev_qtd->hw_next = qtd;
        }

        urb->hcpriv = qh;
        return qh;
}

static void qtd_list_free(struct isp1760_hcd *priv, struct urb *urb,
                struct list_head *qtd_list)
{
        struct list_head *entry, *temp;

        list_for_each_safe(entry, temp, qtd_list) {
                struct isp1760_qtd      *qtd;

                qtd = list_entry(entry, struct isp1760_qtd, qtd_list);
                list_del(&qtd->qtd_list);
                isp1760_qtd_free(qtd);
        }
}

static int isp1760_prepare_enqueue(struct isp1760_hcd *priv, struct urb *urb,
                struct list_head *qtd_list, gfp_t mem_flags, packet_enqueue *p)
{
        struct isp1760_qtd         *qtd;
        int                     epnum;
        unsigned long           flags;
        struct isp1760_qh          *qh = NULL;
        int                     rc;
        int qh_busy;

        qtd = list_entry(qtd_list->next, struct isp1760_qtd, qtd_list);
        epnum = urb->ep->desc.bEndpointAddress;

        spin_lock_irqsave(&priv->lock, flags);
        if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &priv_to_hcd(priv)->flags)) {
                rc = -ESHUTDOWN;
                goto done;
        }
        rc = usb_hcd_link_urb_to_ep(priv_to_hcd(priv), urb);
        if (rc)
                goto done;

        qh = urb->ep->hcpriv;
        if (qh)
                qh_busy = !list_empty(&qh->qtd_list);
        else
                qh_busy = 0;

        qh = qh_append_tds(priv, urb, qtd_list, epnum, &urb->ep->hcpriv);
        if (!qh) {
                usb_hcd_unlink_urb_from_ep(priv_to_hcd(priv), urb);
                rc = -ENOMEM;
                goto done;
        }

        if (!qh_busy)
                p(priv_to_hcd(priv), qh, qtd);

done:
        spin_unlock_irqrestore(&priv->lock, flags);
        if (!qh)
                qtd_list_free(priv, urb, qtd_list);
        return rc;
}

static struct isp1760_qtd *isp1760_qtd_alloc(struct isp1760_hcd *priv,
                gfp_t flags)
{
        struct isp1760_qtd *qtd;

        qtd = kmem_cache_zalloc(qtd_cachep, flags);
        if (qtd)
                INIT_LIST_HEAD(&qtd->qtd_list);

        return qtd;
}

/*
 * create a list of filled qtds for this URB; won't link into qh.
 */
static struct list_head *qh_urb_transaction(struct isp1760_hcd *priv,
                struct urb *urb, struct list_head *head, gfp_t flags)
{
        struct isp1760_qtd *qtd, *qtd_prev;
        void *buf;
        int len, maxpacket;
        int is_input;
        u32 token;

        /*
         * URBs map to sequences of QTDs:  one logical transaction
         */
        qtd = isp1760_qtd_alloc(priv, flags);
        if (!qtd)
                return NULL;

        list_add_tail(&qtd->qtd_list, head);
        qtd->urb = urb;
        urb->status = -EINPROGRESS;

        token = 0;
        /* for split transactions, SplitXState initialized to zero */

        len = urb->transfer_buffer_length;
        is_input = usb_pipein(urb->pipe);
        if (usb_pipecontrol(urb->pipe)) {
                /* SETUP pid */
                qtd_fill(qtd, urb->setup_packet,
                                sizeof(struct usb_ctrlrequest),
                                token | SETUP_PID);

                /* ... and always at least one more pid */
                token ^= DATA_TOGGLE;
                qtd_prev = qtd;
                qtd = isp1760_qtd_alloc(priv, flags);
                if (!qtd)
                        goto cleanup;
                qtd->urb = urb;
                qtd_prev->hw_next = qtd;
                list_add_tail(&qtd->qtd_list, head);

                /* for zero length DATA stages, STATUS is always IN */
                if (len == 0)
                        token |= IN_PID;
        }

        /*
         * data transfer stage:  buffer setup
         */
        buf = urb->transfer_buffer;

        if (is_input)
                token |= IN_PID;
        else
                token |= OUT_PID;

        maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input));

        /*
         * buffer gets wrapped in one or more qtds;
         * last one may be "short" (including zero len)
         * and may serve as a control status ack
         */
        for (;;) {
                int this_qtd_len;

                if (!buf && len) {
                        /* XXX This looks like usb storage / SCSI bug */
                        printk(KERN_ERR "buf is null, dma is %08lx len is %d\n",
                                        (long unsigned)urb->transfer_dma, len);
                        WARN_ON(1);
                }

                this_qtd_len = qtd_fill(qtd, buf, len, token);
                len -= this_qtd_len;
                buf += this_qtd_len;

                /* qh makes control packets use qtd toggle; maybe switch it */
                if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
                        token ^= DATA_TOGGLE;

                if (len <= 0)
                        break;

                qtd_prev = qtd;
                qtd = isp1760_qtd_alloc(priv, flags);
                if (!qtd)
                        goto cleanup;
                qtd->urb = urb;
                qtd_prev->hw_next = qtd;
                list_add_tail(&qtd->qtd_list, head);
        }

        /*
         * control requests may need a terminating data "status" ack;
         * bulk ones may need a terminating short packet (zero length).
         */
        if (urb->transfer_buffer_length != 0) {
                int one_more = 0;

                if (usb_pipecontrol(urb->pipe)) {
                        one_more = 1;
                        /* "in" <--> "out"  */
                        token ^= IN_PID;
                        /* force DATA1 */
                        token |= DATA_TOGGLE;
                } else if (usb_pipebulk(urb->pipe)
                                && (urb->transfer_flags & URB_ZERO_PACKET)
                                && !(urb->transfer_buffer_length % maxpacket)) {
                        one_more = 1;
                }
                if (one_more) {
                        qtd_prev = qtd;
                        qtd = isp1760_qtd_alloc(priv, flags);
                        if (!qtd)
                                goto cleanup;
                        qtd->urb = urb;
                        qtd_prev->hw_next = qtd;
                        list_add_tail(&qtd->qtd_list, head);

                        /* never any data in such packets */
                        qtd_fill(qtd, NULL, 0, token);
                }
        }

        qtd->status = URB_COMPLETE_NOTIFY;
        return head;

cleanup:
        qtd_list_free(priv, urb, head);
        return NULL;
}

static int isp1760_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
                gfp_t mem_flags)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        struct list_head qtd_list;
        packet_enqueue *pe;

        INIT_LIST_HEAD(&qtd_list);

        switch (usb_pipetype(urb->pipe)) {
        case PIPE_CONTROL:
        case PIPE_BULK:

                if (!qh_urb_transaction(priv, urb, &qtd_list, mem_flags))
                        return -ENOMEM;
                pe =  enqueue_an_ATL_packet;
                break;

        case PIPE_INTERRUPT:
                if (!qh_urb_transaction(priv, urb, &qtd_list, mem_flags))
                        return -ENOMEM;
                pe = enqueue_an_INT_packet;
                break;

        case PIPE_ISOCHRONOUS:
                printk(KERN_ERR "PIPE_ISOCHRONOUS ain't supported\n");
        default:
                return -EPIPE;
        }

        return isp1760_prepare_enqueue(priv, urb, &qtd_list, mem_flags, pe);
}

static int isp1760_urb_dequeue(struct usb_hcd *hcd, struct urb *urb,
                int status)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        struct inter_packet_info *ints;
        u32 i;
        u32 reg_base, or_reg, skip_reg;
        unsigned long flags;
        struct ptd ptd;
        packet_enqueue *pe;

        switch (usb_pipetype(urb->pipe)) {
        case PIPE_ISOCHRONOUS:
                return -EPIPE;
                break;

        case PIPE_INTERRUPT:
                ints = priv->int_ints;
                reg_base = INT_REGS_OFFSET;
                or_reg = HC_INT_IRQ_MASK_OR_REG;
                skip_reg = HC_INT_PTD_SKIPMAP_REG;
                pe = enqueue_an_INT_packet;
                break;

        default:
                ints = priv->atl_ints;
                reg_base = ATL_REGS_OFFSET;
                or_reg = HC_ATL_IRQ_MASK_OR_REG;
                skip_reg = HC_ATL_PTD_SKIPMAP_REG;
                pe =  enqueue_an_ATL_packet;
                break;
        }

        memset(&ptd, 0, sizeof(ptd));
        spin_lock_irqsave(&priv->lock, flags);

        for (i = 0; i < 32; i++) {
                if (ints->urb == urb) {
                        u32 skip_map;
                        u32 or_map;
                        struct isp1760_qtd *qtd;
                        struct isp1760_qh *qh = ints->qh;

                        skip_map = isp1760_readl(hcd->regs + skip_reg);
                        skip_map |= 1 << i;
                        isp1760_writel(skip_map, hcd->regs + skip_reg);

                        or_map = isp1760_readl(hcd->regs + or_reg);
                        or_map &= ~(1 << i);
                        isp1760_writel(or_map, hcd->regs + or_reg);

                        priv_write_copy(priv, (u32 *)&ptd, hcd->regs + reg_base
                                        + i * sizeof(ptd), sizeof(ptd));
                        qtd = ints->qtd;
                        qtd = clean_up_qtdlist(qtd);

                        free_mem(priv, ints->payload);

                        ints->urb = NULL;
                        ints->qh = NULL;
                        ints->qtd = NULL;
                        ints->data_buffer = NULL;
                        ints->payload = 0;

                        isp1760_urb_done(priv, urb, status);
                        if (qtd)
                                pe(hcd, qh, qtd);
                        break;

                } else if (ints->qtd) {
                        struct isp1760_qtd *qtd, *prev_qtd = ints->qtd;

                        for (qtd = ints->qtd->hw_next; qtd; qtd = qtd->hw_next) {
                                if (qtd->urb == urb) {
                                        prev_qtd->hw_next = clean_up_qtdlist(qtd);
                                        isp1760_urb_done(priv, urb, status);
                                        break;
                                }
                                prev_qtd = qtd;
                        }
                        /* we found the urb before the end of the list */
                        if (qtd)
                                break;
                }
                ints++;
        }

        spin_unlock_irqrestore(&priv->lock, flags);
        return 0;
}

static irqreturn_t isp1760_irq(struct usb_hcd *usb_hcd)
{
        struct isp1760_hcd *priv = hcd_to_priv(usb_hcd);
        u32 imask;
        irqreturn_t irqret = IRQ_NONE;

        spin_lock(&priv->lock);

        if (!(usb_hcd->state & HC_STATE_RUNNING))
                goto leave;

        imask = isp1760_readl(usb_hcd->regs + HC_INTERRUPT_REG);
        if (unlikely(!imask))
                goto leave;

        isp1760_writel(imask, usb_hcd->regs + HC_INTERRUPT_REG);
        if (imask & HC_ATL_INT)
                do_atl_int(usb_hcd);

        if (imask & HC_INTL_INT)
                do_intl_int(usb_hcd);

        irqret = IRQ_HANDLED;
leave:
        spin_unlock(&priv->lock);
        return irqret;
}

static int isp1760_hub_status_data(struct usb_hcd *hcd, char *buf)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        u32 temp, status = 0;
        u32 mask;
        int retval = 1;
        unsigned long flags;

        /* if !USB_SUSPEND, root hub timers won't get shut down ... */
        if (!HC_IS_RUNNING(hcd->state))
                return 0;

        /* init status to no-changes */
        buf[0] = 0;
        mask = PORT_CSC;

        spin_lock_irqsave(&priv->lock, flags);
        temp = isp1760_readl(hcd->regs + HC_PORTSC1);

        if (temp & PORT_OWNER) {
                if (temp & PORT_CSC) {
                        temp &= ~PORT_CSC;
                        isp1760_writel(temp, hcd->regs + HC_PORTSC1);
                        goto done;
                }
        }

        /*
         * Return status information even for ports with OWNER set.
         * Otherwise khubd wouldn't see the disconnect event when a
         * high-speed device is switched over to the companion
         * controller by the user.
         */

        if ((temp & mask) != 0
                        || ((temp & PORT_RESUME) != 0
                                && time_after_eq(jiffies,
                                        priv->reset_done))) {
                buf [0] |= 1 << (0 + 1);
                status = STS_PCD;
        }
        /* FIXME autosuspend idle root hubs */
done:
        spin_unlock_irqrestore(&priv->lock, flags);
        return status ? retval : 0;
}

static void isp1760_hub_descriptor(struct isp1760_hcd *priv,
                struct usb_hub_descriptor *desc)
{
        int ports = HCS_N_PORTS(priv->hcs_params);
        u16 temp;

        desc->bDescriptorType = 0x29;
        /* priv 1.0, 2.3.9 says 20ms max */
        desc->bPwrOn2PwrGood = 10;
        desc->bHubContrCurrent = 0;

        desc->bNbrPorts = ports;
        temp = 1 + (ports / 8);
        desc->bDescLength = 7 + 2 * temp;

        /* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
        memset(&desc->bitmap[0], 0, temp);
        memset(&desc->bitmap[temp], 0xff, temp);

        /* per-port overcurrent reporting */
        temp = 0x0008;
        if (HCS_PPC(priv->hcs_params))
                /* per-port power control */
                temp |= 0x0001;
        else
                /* no power switching */
                temp |= 0x0002;
        desc->wHubCharacteristics = cpu_to_le16(temp);
}

#define PORT_WAKE_BITS  (PORT_WKOC_E|PORT_WKDISC_E|PORT_WKCONN_E)

static int check_reset_complete(struct isp1760_hcd *priv, int index,
                u32 __iomem *status_reg, int port_status)
{
        if (!(port_status & PORT_CONNECT))
                return port_status;

        /* if reset finished and it's still not enabled -- handoff */
        if (!(port_status & PORT_PE)) {

                printk(KERN_ERR "port %d full speed --> companion\n",
                        index + 1);

                port_status |= PORT_OWNER;
                port_status &= ~PORT_RWC_BITS;
                isp1760_writel(port_status, status_reg);

        } else
                printk(KERN_ERR "port %d high speed\n", index + 1);

        return port_status;
}

static int isp1760_hub_control(struct usb_hcd *hcd, u16 typeReq,
                u16 wValue, u16 wIndex, char *buf, u16 wLength)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        int ports = HCS_N_PORTS(priv->hcs_params);
        u32 __iomem *status_reg = hcd->regs + HC_PORTSC1;
        u32 temp, status;
        unsigned long flags;
        int retval = 0;
        unsigned selector;

        /*
         * FIXME:  support SetPortFeatures USB_PORT_FEAT_INDICATOR.
         * HCS_INDICATOR may say we can change LEDs to off/amber/green.
         * (track current state ourselves) ... blink for diagnostics,
         * power, "this is the one", etc.  EHCI spec supports this.
         */

        spin_lock_irqsave(&priv->lock, flags);
        switch (typeReq) {
        case ClearHubFeature:
                switch (wValue) {
                case C_HUB_LOCAL_POWER:
                case C_HUB_OVER_CURRENT:
                        /* no hub-wide feature/status flags */
                        break;
                default:
                        goto error;
                }
                break;
        case ClearPortFeature:
                if (!wIndex || wIndex > ports)
                        goto error;
                wIndex--;
                temp = isp1760_readl(status_reg);

                /*
                 * Even if OWNER is set, so the port is owned by the
                 * companion controller, khubd needs to be able to clear
                 * the port-change status bits (especially
                 * USB_PORT_FEAT_C_CONNECTION).
                 */

                switch (wValue) {
                case USB_PORT_FEAT_ENABLE:
                        isp1760_writel(temp & ~PORT_PE, status_reg);
                        break;
                case USB_PORT_FEAT_C_ENABLE:
                        /* XXX error? */
                        break;
                case USB_PORT_FEAT_SUSPEND:
                        if (temp & PORT_RESET)
                                goto error;

                        if (temp & PORT_SUSPEND) {
                                if ((temp & PORT_PE) == 0)
                                        goto error;
                                /* resume signaling for 20 msec */
                                temp &= ~(PORT_RWC_BITS);
                                isp1760_writel(temp | PORT_RESUME,
                                                status_reg);
                                priv->reset_done = jiffies +
                                        msecs_to_jiffies(20);
                        }
                        break;
                case USB_PORT_FEAT_C_SUSPEND:
                        /* we auto-clear this feature */
                        break;
                case USB_PORT_FEAT_POWER:
                        if (HCS_PPC(priv->hcs_params))
                                isp1760_writel(temp & ~PORT_POWER, status_reg);
                        break;
                case USB_PORT_FEAT_C_CONNECTION:
                        isp1760_writel(temp | PORT_CSC,
                                        status_reg);
                        break;
                case USB_PORT_FEAT_C_OVER_CURRENT:
                        /* XXX error ?*/
                        break;
                case USB_PORT_FEAT_C_RESET:
                        /* GetPortStatus clears reset */
                        break;
                default:
                        goto error;
                }
                isp1760_readl(hcd->regs + HC_USBCMD);
                break;
        case GetHubDescriptor:
                isp1760_hub_descriptor(priv, (struct usb_hub_descriptor *)
                        buf);
                break;
        case GetHubStatus:
                /* no hub-wide feature/status flags */
                memset(buf, 0, 4);
                break;
        case GetPortStatus:
                if (!wIndex || wIndex > ports)
                        goto error;
                wIndex--;
                status = 0;
                temp = isp1760_readl(status_reg);

                /* wPortChange bits */
                if (temp & PORT_CSC)
                        status |= 1 << USB_PORT_FEAT_C_CONNECTION;


                /* whoever resumes must GetPortStatus to complete it!! */
                if (temp & PORT_RESUME) {
                        printk(KERN_ERR "Port resume should be skipped.\n");

                        /* Remote Wakeup received? */
                        if (!priv->reset_done) {
                                /* resume signaling for 20 msec */
                                priv->reset_done = jiffies
                                                + msecs_to_jiffies(20);
                                /* check the port again */
                                mod_timer(&priv_to_hcd(priv)->rh_timer,
                                                priv->reset_done);
                        }

                        /* resume completed? */
                        else if (time_after_eq(jiffies,
                                        priv->reset_done)) {
                                status |= 1 << USB_PORT_FEAT_C_SUSPEND;

                                priv->reset_done = 0;

                                /* stop resume signaling */
                                temp = isp1760_readl(status_reg);
                                isp1760_writel(
                                        temp & ~(PORT_RWC_BITS | PORT_RESUME),
                                        status_reg);
                                retval = handshake(priv, status_reg,
                                           PORT_RESUME, 0, 2000 /* 2msec */);
                                if (retval != 0) {
                                        isp1760_err(priv,
                                                "port %d resume error %d\n",
                                                wIndex + 1, retval);
                                        goto error;
                                }
                                temp &= ~(PORT_SUSPEND|PORT_RESUME|(3<<10));
                        }
                }

                /* whoever resets must GetPortStatus to complete it!! */
                if ((temp & PORT_RESET)
                                && time_after_eq(jiffies,
                                        priv->reset_done)) {
                        status |= 1 << USB_PORT_FEAT_C_RESET;
                        priv->reset_done = 0;

                        /* force reset to complete */
                        isp1760_writel(temp & ~PORT_RESET,
                                        status_reg);
                        /* REVISIT:  some hardware needs 550+ usec to clear
                         * this bit; seems too long to spin routinely...
                         */
                        retval = handshake(priv, status_reg,
                                        PORT_RESET, 0, 750);
                        if (retval != 0) {
                                isp1760_err(priv, "port %d reset error %d\n",
                                                wIndex + 1, retval);
                                goto error;
                        }

                        /* see what we found out */
                        temp = check_reset_complete(priv, wIndex, status_reg,
                                        isp1760_readl(status_reg));
                }
                /*
                 * Even if OWNER is set, there's no harm letting khubd
                 * see the wPortStatus values (they should all be 0 except
                 * for PORT_POWER anyway).
                 */

                if (temp & PORT_OWNER)
                        printk(KERN_ERR "Warning: PORT_OWNER is set\n");

                if (temp & PORT_CONNECT) {
                        status |= 1 << USB_PORT_FEAT_CONNECTION;
                        /* status may be from integrated TT */
                        status |= ehci_port_speed(priv, temp);
                }
                if (temp & PORT_PE)
                        status |= 1 << USB_PORT_FEAT_ENABLE;
                if (temp & (PORT_SUSPEND|PORT_RESUME))
                        status |= 1 << USB_PORT_FEAT_SUSPEND;
                if (temp & PORT_RESET)
                        status |= 1 << USB_PORT_FEAT_RESET;
                if (temp & PORT_POWER)
                        status |= 1 << USB_PORT_FEAT_POWER;

                put_unaligned(cpu_to_le32(status), (__le32 *) buf);
                break;
        case SetHubFeature:
                switch (wValue) {
                case C_HUB_LOCAL_POWER:
                case C_HUB_OVER_CURRENT:
                        /* no hub-wide feature/status flags */
                        break;
                default:
                        goto error;
                }
                break;
        case SetPortFeature:
                selector = wIndex >> 8;
                wIndex &= 0xff;
                if (!wIndex || wIndex > ports)
                        goto error;
                wIndex--;
                temp = isp1760_readl(status_reg);
                if (temp & PORT_OWNER)
                        break;

/*              temp &= ~PORT_RWC_BITS; */
                switch (wValue) {
                case USB_PORT_FEAT_ENABLE:
                        isp1760_writel(temp | PORT_PE, status_reg);
                        break;

                case USB_PORT_FEAT_SUSPEND:
                        if ((temp & PORT_PE) == 0
                                        || (temp & PORT_RESET) != 0)
                                goto error;

                        isp1760_writel(temp | PORT_SUSPEND, status_reg);
                        break;
                case USB_PORT_FEAT_POWER:
                        if (HCS_PPC(priv->hcs_params))
                                isp1760_writel(temp | PORT_POWER,
                                                status_reg);
                        break;
                case USB_PORT_FEAT_RESET:
                        if (temp & PORT_RESUME)
                                goto error;
                        /* line status bits may report this as low speed,
                         * which can be fine if this root hub has a
                         * transaction translator built in.
                         */
                        if ((temp & (PORT_PE|PORT_CONNECT)) == PORT_CONNECT
                                        && PORT_USB11(temp)) {
                                temp |= PORT_OWNER;
                        } else {
                                temp |= PORT_RESET;
                                temp &= ~PORT_PE;

                                /*
                                 * caller must wait, then call GetPortStatus
                                 * usb 2.0 spec says 50 ms resets on root
                                 */
                                priv->reset_done = jiffies +
                                        msecs_to_jiffies(50);
                        }
                        isp1760_writel(temp, status_reg);
                        break;
                default:
                        goto error;
                }
                isp1760_readl(hcd->regs + HC_USBCMD);
                break;

        default:
error:
                /* "stall" on error */
                retval = -EPIPE;
        }
        spin_unlock_irqrestore(&priv->lock, flags);
        return retval;
}

static void isp1760_endpoint_disable(struct usb_hcd *usb_hcd,
                struct usb_host_endpoint *ep)
{
        struct isp1760_hcd *priv = hcd_to_priv(usb_hcd);
        struct isp1760_qh *qh;
        struct isp1760_qtd *qtd;
        unsigned long flags;

        spin_lock_irqsave(&priv->lock, flags);
        qh = ep->hcpriv;
        if (!qh)
                goto out;

        ep->hcpriv = NULL;
        do {
                /* more than entry might get removed */
                if (list_empty(&qh->qtd_list))
                        break;

                qtd = list_first_entry(&qh->qtd_list, struct isp1760_qtd,
                                qtd_list);

                if (qtd->status & URB_ENQUEUED) {

                        spin_unlock_irqrestore(&priv->lock, flags);
                        isp1760_urb_dequeue(usb_hcd, qtd->urb, -ECONNRESET);
                        spin_lock_irqsave(&priv->lock, flags);
                } else {
                        struct urb *urb;

                        urb = qtd->urb;
                        clean_up_qtdlist(qtd);
                        isp1760_urb_done(priv, urb, -ECONNRESET);
                }
        } while (1);

        qh_destroy(qh);
        /* remove requests and leak them.
         * ATL are pretty fast done, INT could take a while...
         * The latter shoule be removed
         */
out:
        spin_unlock_irqrestore(&priv->lock, flags);
}

static int isp1760_get_frame(struct usb_hcd *hcd)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        u32 fr;

        fr = isp1760_readl(hcd->regs + HC_FRINDEX);
        return (fr >> 3) % priv->periodic_size;
}

static void isp1760_stop(struct usb_hcd *hcd)
{
        struct isp1760_hcd *priv = hcd_to_priv(hcd);
        u32 temp;

        isp1760_hub_control(hcd, ClearPortFeature, USB_PORT_FEAT_POWER, 1,
                        NULL, 0);
        mdelay(20);

        spin_lock_irq(&priv->lock);
        ehci_reset(priv);
        /* Disable IRQ */
        temp = isp1760_readl(hcd->regs + HC_HW_MODE_CTRL);
        isp1760_writel(temp &= ~HW_GLOBAL_INTR_EN, hcd->regs + HC_HW_MODE_CTRL);
        spin_unlock_irq(&priv->lock);

        isp1760_writel(0, hcd->regs + HC_CONFIGFLAG);
}

static void isp1760_shutdown(struct usb_hcd *hcd)
{
        u32 command, temp;

        isp1760_stop(hcd);
        temp = isp1760_readl(hcd->regs + HC_HW_MODE_CTRL);
        isp1760_writel(temp &= ~HW_GLOBAL_INTR_EN, hcd->regs + HC_HW_MODE_CTRL);

        command = isp1760_readl(hcd->regs + HC_USBCMD);
        command &= ~CMD_RUN;
        isp1760_writel(command, hcd->regs + HC_USBCMD);
}

static const struct hc_driver isp1760_hc_driver = {
        .description            = "isp1760-hcd",
        .product_desc           = "NXP ISP1760 USB Host Controller",
        .hcd_priv_size          = sizeof(struct isp1760_hcd),
        .irq                    = isp1760_irq,
        .flags                  = HCD_MEMORY | HCD_USB2,
        .reset                  = isp1760_hc_setup,
        .start                  = isp1760_run,
        .stop                   = isp1760_stop,
        .shutdown               = isp1760_shutdown,
        .urb_enqueue            = isp1760_urb_enqueue,
        .urb_dequeue            = isp1760_urb_dequeue,
        .endpoint_disable       = isp1760_endpoint_disable,
        .get_frame_number       = isp1760_get_frame,
        .hub_status_data        = isp1760_hub_status_data,
        .hub_control            = isp1760_hub_control,
};

int __init init_kmem_once(void)
{
        qtd_cachep = kmem_cache_create("isp1760_qtd",
                        sizeof(struct isp1760_qtd), 0, SLAB_TEMPORARY |
                        SLAB_MEM_SPREAD, NULL);

        if (!qtd_cachep)
                return -ENOMEM;

        qh_cachep = kmem_cache_create("isp1760_qh", sizeof(struct isp1760_qh),
                        0, SLAB_TEMPORARY | SLAB_MEM_SPREAD, NULL);

        if (!qh_cachep) {
                kmem_cache_destroy(qtd_cachep);
                return -ENOMEM;
        }

        return 0;
}

void deinit_kmem_cache(void)
{
        kmem_cache_destroy(qtd_cachep);
        kmem_cache_destroy(qh_cachep);
}

struct usb_hcd *isp1760_register(phys_addr_t res_start, resource_size_t res_len,
                                 int irq, unsigned long irqflags,
                                 struct device *dev, const char *busname,
                                 unsigned int devflags)
{
        struct usb_hcd *hcd;
        struct isp1760_hcd *priv;
        int ret;

        if (usb_disabled())
                return ERR_PTR(-ENODEV);

        /* prevent usb-core allocating DMA pages */
        dev->dma_mask = NULL;

        hcd = usb_create_hcd(&isp1760_hc_driver, dev, dev_name(dev));
        if (!hcd)
                return ERR_PTR(-ENOMEM);

        priv = hcd_to_priv(hcd);
        priv->devflags = devflags;
        init_memory(priv);
        hcd->regs = ioremap(res_start, res_len);
        if (!hcd->regs) {
                ret = -EIO;
                goto err_put;
        }

        hcd->irq = irq;
        hcd->rsrc_start = res_start;
        hcd->rsrc_len = res_len;

        ret = usb_add_hcd(hcd, irq, irqflags);
        if (ret)
                goto err_unmap;

        return hcd;

err_unmap:
         iounmap(hcd->regs);

err_put:
         usb_put_hcd(hcd);

         return ERR_PTR(ret);
}

MODULE_DESCRIPTION("Driver for the ISP1760 USB-controller from NXP");
MODULE_AUTHOR("Sebastian Siewior <bigeasy@linuxtronix.de>");
MODULE_LICENSE("GPL v2");