/* -----------------------------------------------------------------------------
 * Copyright (c) 2011 Ozmo Inc
 * Released under the GNU General Public License Version 2 (GPLv2).
 *
 * This file provides the implementation of a USB host controller device that
 * does not have any associated hardware. Instead the virtual device is
 * connected to the WiFi network and emulates the operation of a USB hcd by
 * receiving and sending network frames.
 * Note:
 * We take great pains to reduce the amount of code where interrupts need to be
 * disabled and in this respect we are different from standard HCD's. In
 * particular we don't want in_irq() code bleeding over to the protocol side of
 * the driver.
 * The troublesome functions are the urb enqueue and dequeue functions both of
 * which can be called in_irq(). So for these functions we put the urbs into a
 * queue and request a tasklet to process them. This means that a spinlock with
 * interrupts disabled must be held for insertion and removal but most code is
 * is in tasklet or soft irq context. The lock that protects this list is called
 * the tasklet lock and serves the purpose of the 'HCD lock' which must be held
 * when calling the following functions.
 *   usb_hcd_link_urb_to_ep()
 *   usb_hcd_unlink_urb_from_ep()
 *   usb_hcd_flush_endpoint()
 *   usb_hcd_check_unlink_urb()
 * -----------------------------------------------------------------------------
 */
#include <linux/platform_device.h>
#include <linux/usb.h>
#include <linux/slab.h>
#include <linux/export.h>
#include "linux/usb/hcd.h"
#include <asm/unaligned.h>
#include "ozdbg.h"
#include "ozusbif.h"
#include "ozurbparanoia.h"
#include "ozhcd.h"

/*
 * Number of units of buffering to capture for an isochronous IN endpoint before
 * allowing data to be indicated up.
 */
#define OZ_IN_BUFFERING_UNITS   100

/* Name of our platform device.
 */
#define OZ_PLAT_DEV_NAME        "ozwpan"

/* Maximum number of free urb links that can be kept in the pool.
 */
#define OZ_MAX_LINK_POOL_SIZE   16

/* Get endpoint object from the containing link.
 */
#define ep_from_link(__e) container_of((__e), struct oz_endpoint, link)

/*EP0 timeout before ep0 request is again added to TX queue. (13*8 = 98mSec)
 */
#define EP0_TIMEOUT_COUNTER 13

/* Debounce time HCD driver should wait before unregistering.
 */
#define OZ_HUB_DEBOUNCE_TIMEOUT 1500

/*
 * Used to link urbs together and also store some status information for each
 * urb.
 * A cache of these are kept in a pool to reduce number of calls to kmalloc.
 */
struct oz_urb_link {
        struct list_head link;
        struct urb *urb;
        struct oz_port *port;
        u8 req_id;
        u8 ep_num;
        unsigned submit_counter;
};

/* Holds state information about a USB endpoint.
 */
#define OZ_EP_BUFFER_SIZE_ISOC  (1024 * 24)
#define OZ_EP_BUFFER_SIZE_INT   512
struct oz_endpoint {
        struct list_head urb_list;      /* List of oz_urb_link items. */
        struct list_head link;          /* For isoc ep, links in to isoc
                                           lists of oz_port. */
        struct timespec timestamp;
        int credit;
        int credit_ceiling;
        u8 ep_num;
        u8 attrib;
        u8 *buffer;
        int buffer_size;
        int in_ix;
        int out_ix;
        int buffered_units;
        unsigned flags;
        int start_frame;
};

/* Bits in the flags field. */
#define OZ_F_EP_BUFFERING       0x1
#define OZ_F_EP_HAVE_STREAM     0x2

/* Holds state information about a USB interface.
 */
struct oz_interface {
        unsigned ep_mask;
        u8 alt;
};

/* Holds state information about an hcd port.
 */
#define OZ_NB_ENDPOINTS 16
struct oz_port {
        unsigned flags;
        unsigned status;
        void *hpd;
        struct oz_hcd *ozhcd;
        spinlock_t port_lock;
        u8 bus_addr;
        u8 next_req_id;
        u8 config_num;
        int num_iface;
        struct oz_interface *iface;
        struct oz_endpoint *out_ep[OZ_NB_ENDPOINTS];
        struct oz_endpoint *in_ep[OZ_NB_ENDPOINTS];
        struct list_head isoc_out_ep;
        struct list_head isoc_in_ep;
};

#define OZ_PORT_F_PRESENT       0x1
#define OZ_PORT_F_CHANGED       0x2
#define OZ_PORT_F_DYING         0x4

/* Data structure in the private context area of struct usb_hcd.
 */
#define OZ_NB_PORTS     8
struct oz_hcd {
        spinlock_t hcd_lock;
        struct list_head urb_pending_list;
        struct list_head urb_cancel_list;
        struct list_head orphanage;
        int conn_port; /* Port that is currently connecting, -1 if none.*/
        struct oz_port ports[OZ_NB_PORTS];
        uint flags;
        struct usb_hcd *hcd;
};

/* Bits in flags field.
 */
#define OZ_HDC_F_SUSPENDED      0x1

/*
 * Static function prototypes.
 */
static int oz_hcd_start(struct usb_hcd *hcd);
static void oz_hcd_stop(struct usb_hcd *hcd);
static void oz_hcd_shutdown(struct usb_hcd *hcd);
static int oz_hcd_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
                                gfp_t mem_flags);
static int oz_hcd_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status);
static void oz_hcd_endpoint_disable(struct usb_hcd *hcd,
                                struct usb_host_endpoint *ep);
static void oz_hcd_endpoint_reset(struct usb_hcd *hcd,
                                struct usb_host_endpoint *ep);
static int oz_hcd_get_frame_number(struct usb_hcd *hcd);
static int oz_hcd_hub_status_data(struct usb_hcd *hcd, char *buf);
static int oz_hcd_hub_control(struct usb_hcd *hcd, u16 req_type, u16 wvalue,
                                u16 windex, char *buf, u16 wlength);
static int oz_hcd_bus_suspend(struct usb_hcd *hcd);
static int oz_hcd_bus_resume(struct usb_hcd *hcd);
static int oz_plat_probe(struct platform_device *dev);
static int oz_plat_remove(struct platform_device *dev);
static void oz_plat_shutdown(struct platform_device *dev);
static int oz_plat_suspend(struct platform_device *dev, pm_message_t msg);
static int oz_plat_resume(struct platform_device *dev);
static void oz_urb_process_tasklet(unsigned long unused);
static int oz_build_endpoints_for_config(struct usb_hcd *hcd,
                struct oz_port *port, struct usb_host_config *config,
                gfp_t mem_flags);
static void oz_clean_endpoints_for_config(struct usb_hcd *hcd,
                                struct oz_port *port);
static int oz_build_endpoints_for_interface(struct usb_hcd *hcd,
                        struct oz_port *port,
                        struct usb_host_interface *intf, gfp_t mem_flags);
static void oz_clean_endpoints_for_interface(struct usb_hcd *hcd,
                        struct oz_port *port, int if_ix);
static void oz_process_ep0_urb(struct oz_hcd *ozhcd, struct urb *urb,
                gfp_t mem_flags);
static struct oz_urb_link *oz_remove_urb(struct oz_endpoint *ep,
                struct urb *urb);
static void oz_hcd_clear_orphanage(struct oz_hcd *ozhcd, int status);

/*
 * Static external variables.
 */
static struct platform_device *g_plat_dev;
static struct oz_hcd *g_ozhcd;
static DEFINE_SPINLOCK(g_hcdlock);      /* Guards g_ozhcd. */
static const char g_hcd_name[] = "Ozmo WPAN";
static struct list_head *g_link_pool;
static int g_link_pool_size;
static DEFINE_SPINLOCK(g_link_lock);
static DEFINE_SPINLOCK(g_tasklet_lock);
static struct tasklet_struct g_urb_process_tasklet;
static struct tasklet_struct g_urb_cancel_tasklet;
static atomic_t g_pending_urbs = ATOMIC_INIT(0);
static atomic_t g_usb_frame_number = ATOMIC_INIT(0);
static const struct hc_driver g_oz_hc_drv = {
        .description =          g_hcd_name,
        .product_desc =         "Ozmo Devices WPAN",
        .hcd_priv_size =        sizeof(struct oz_hcd),
        .flags =                HCD_USB11,
        .start =                oz_hcd_start,
        .stop =                 oz_hcd_stop,
        .shutdown =             oz_hcd_shutdown,
        .urb_enqueue =          oz_hcd_urb_enqueue,
        .urb_dequeue =          oz_hcd_urb_dequeue,
        .endpoint_disable =     oz_hcd_endpoint_disable,
        .endpoint_reset =       oz_hcd_endpoint_reset,
        .get_frame_number =     oz_hcd_get_frame_number,
        .hub_status_data =      oz_hcd_hub_status_data,
        .hub_control =          oz_hcd_hub_control,
        .bus_suspend =          oz_hcd_bus_suspend,
        .bus_resume =           oz_hcd_bus_resume,
};

static struct platform_driver g_oz_plat_drv = {
        .probe = oz_plat_probe,
        .remove = oz_plat_remove,
        .shutdown = oz_plat_shutdown,
        .suspend = oz_plat_suspend,
        .resume = oz_plat_resume,
        .driver = {
                .name = OZ_PLAT_DEV_NAME,
                .owner = THIS_MODULE,
        },
};

/*
 * Gets our private context area (which is of type struct oz_hcd) from the
 * usb_hcd structure.
 * Context: any
 */
static inline struct oz_hcd *oz_hcd_private(struct usb_hcd *hcd)
{
        return (struct oz_hcd *)hcd->hcd_priv;
}

/*
 * Searches list of ports to find the index of the one with a specified  USB
 * bus address. If none of the ports has the bus address then the connection
 * port is returned, if there is one or -1 otherwise.
 * Context: any
 */
static int oz_get_port_from_addr(struct oz_hcd *ozhcd, u8 bus_addr)
{
        int i;

        for (i = 0; i < OZ_NB_PORTS; i++) {
                if (ozhcd->ports[i].bus_addr == bus_addr)
                        return i;
        }
        return ozhcd->conn_port;
}

/*
 * Allocates an urb link, first trying the pool but going to heap if empty.
 * Context: any
 */
static struct oz_urb_link *oz_alloc_urb_link(void)
{
        struct oz_urb_link *urbl = NULL;
        unsigned long irq_state;

        spin_lock_irqsave(&g_link_lock, irq_state);
        if (g_link_pool) {
                urbl = container_of(g_link_pool, struct oz_urb_link, link);
                g_link_pool = urbl->link.next;
                --g_link_pool_size;
        }
        spin_unlock_irqrestore(&g_link_lock, irq_state);
        if (urbl == NULL)
                urbl = kmalloc(sizeof(struct oz_urb_link), GFP_ATOMIC);
        return urbl;
}

/*
 * Frees an urb link by putting it in the pool if there is enough space or
 * deallocating it to heap otherwise.
 * Context: any
 */
static void oz_free_urb_link(struct oz_urb_link *urbl)
{
        if (urbl) {
                unsigned long irq_state;
                spin_lock_irqsave(&g_link_lock, irq_state);
                if (g_link_pool_size < OZ_MAX_LINK_POOL_SIZE) {
                        urbl->link.next = g_link_pool;
                        g_link_pool = &urbl->link;
                        urbl = NULL;
                        g_link_pool_size++;
                }
                spin_unlock_irqrestore(&g_link_lock, irq_state);
                kfree(urbl);
        }
}

/*
 * Deallocates all the urb links in the pool.
 * Context: unknown
 */
static void oz_empty_link_pool(void)
{
        struct list_head *e;
        unsigned long irq_state;

        spin_lock_irqsave(&g_link_lock, irq_state);
        e = g_link_pool;
        g_link_pool = NULL;
        g_link_pool_size = 0;
        spin_unlock_irqrestore(&g_link_lock, irq_state);
        while (e) {
                struct oz_urb_link *urbl =
                        container_of(e, struct oz_urb_link, link);
                e = e->next;
                kfree(urbl);
        }
}

/*
 * Allocates endpoint structure and optionally a buffer. If a buffer is
 * allocated it immediately follows the endpoint structure.
 * Context: softirq
 */
static struct oz_endpoint *oz_ep_alloc(int buffer_size, gfp_t mem_flags)
{
        struct oz_endpoint *ep =
                kzalloc(sizeof(struct oz_endpoint)+buffer_size, mem_flags);
        if (ep) {
                INIT_LIST_HEAD(&ep->urb_list);
                INIT_LIST_HEAD(&ep->link);
                ep->credit = -1;
                if (buffer_size) {
                        ep->buffer_size = buffer_size;
                        ep->buffer = (u8 *)(ep+1);
                }
        }
        return ep;
}

/*
 * Pre-condition: Must be called with g_tasklet_lock held and interrupts
 * disabled.
 * Context: softirq or process
 */
static struct oz_urb_link *oz_uncancel_urb(struct oz_hcd *ozhcd, struct urb *urb)
{
        struct oz_urb_link *urbl;
        struct list_head *e;

        list_for_each(e, &ozhcd->urb_cancel_list) {
                urbl = container_of(e, struct oz_urb_link, link);
                if (urb == urbl->urb) {
                        list_del_init(e);
                        return urbl;
                }
        }
        return NULL;
}

/*
 * This is called when we have finished processing an urb. It unlinks it from
 * the ep and returns it to the core.
 * Context: softirq or process
 */
static void oz_complete_urb(struct usb_hcd *hcd, struct urb *urb,
                int status)
{
        struct oz_hcd *ozhcd = oz_hcd_private(hcd);
        unsigned long irq_state;
        struct oz_urb_link *cancel_urbl;

        spin_lock_irqsave(&g_tasklet_lock, irq_state);
        usb_hcd_unlink_urb_from_ep(hcd, urb);
        /* Clear hcpriv which will prevent it being put in the cancel list
         * in the event that an attempt is made to cancel it.
         */
        urb->hcpriv = NULL;
        /* Walk the cancel list in case the urb is already sitting there.
         * Since we process the cancel list in a tasklet rather than in
         * the dequeue function this could happen.
         */
        cancel_urbl = oz_uncancel_urb(ozhcd, urb);
        /* Note: we release lock but do not enable local irqs.
         * It appears that usb_hcd_giveback_urb() expects irqs to be disabled,
         * or at least other host controllers disable interrupts at this point
         * so we do the same. We must, however, release the lock otherwise a
         * deadlock will occur if an urb is submitted to our driver in the urb
         * completion function. Because we disable interrupts it is possible
         * that the urb_enqueue function can be called with them disabled.
         */
        spin_unlock(&g_tasklet_lock);
        if (oz_forget_urb(urb)) {
                oz_dbg(ON, "ERROR Unknown URB %p\n", urb);
        } else {
                atomic_dec(&g_pending_urbs);
                usb_hcd_giveback_urb(hcd, urb, status);
        }
        spin_lock(&g_tasklet_lock);
        spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
        if (cancel_urbl)
                oz_free_urb_link(cancel_urbl);
}

/*
 * Deallocates an endpoint including deallocating any associated stream and
 * returning any queued urbs to the core.
 * Context: softirq
 */
static void oz_ep_free(struct oz_port *port, struct oz_endpoint *ep)
{
        if (port) {
                struct list_head list;
                struct oz_hcd *ozhcd = port->ozhcd;
                INIT_LIST_HEAD(&list);
                if (ep->flags & OZ_F_EP_HAVE_STREAM)
                        oz_usb_stream_delete(port->hpd, ep->ep_num);
                /* Transfer URBs to the orphanage while we hold the lock. */
                spin_lock_bh(&ozhcd->hcd_lock);
                /* Note: this works even if ep->urb_list is empty.*/
                list_replace_init(&ep->urb_list, &list);
                /* Put the URBs in the orphanage. */
                list_splice_tail(&list, &ozhcd->orphanage);
                spin_unlock_bh(&ozhcd->hcd_lock);
        }
        oz_dbg(ON, "Freeing endpoint memory\n");
        kfree(ep);
}

/*
 * Context: softirq
 */
static void oz_complete_buffered_urb(struct oz_port *port,
                        struct oz_endpoint *ep,
                        struct urb *urb)
{
        int data_len, available_space, copy_len;

        data_len = ep->buffer[ep->out_ix];
        if (data_len <= urb->transfer_buffer_length)
                available_space = data_len;
        else
                available_space = urb->transfer_buffer_length;

        if (++ep->out_ix == ep->buffer_size)
                ep->out_ix = 0;
        copy_len = ep->buffer_size - ep->out_ix;
        if (copy_len >= available_space)
                copy_len = available_space;
        memcpy(urb->transfer_buffer, &ep->buffer[ep->out_ix], copy_len);

        if (copy_len < available_space) {
                memcpy((urb->transfer_buffer + copy_len), ep->buffer,
                                                (available_space - copy_len));
                ep->out_ix = available_space - copy_len;
        } else {
                ep->out_ix += copy_len;
        }
        urb->actual_length = available_space;
        if (ep->out_ix == ep->buffer_size)
                ep->out_ix = 0;

        ep->buffered_units--;
        oz_dbg(ON, "Trying to give back buffered frame of size=%d\n",
               available_space);
        oz_complete_urb(port->ozhcd->hcd, urb, 0);
}

/*
 * Context: softirq
 */
static int oz_enqueue_ep_urb(struct oz_port *port, u8 ep_addr, int in_dir,
                        struct urb *urb, u8 req_id)
{
        struct oz_urb_link *urbl;
        struct oz_endpoint *ep = NULL;
        int err = 0;

        if (ep_addr >= OZ_NB_ENDPOINTS) {
                oz_dbg(ON, "%s: Invalid endpoint number\n", __func__);
                return -EINVAL;
        }
        urbl = oz_alloc_urb_link();
        if (!urbl)
                return -ENOMEM;
        urbl->submit_counter = 0;
        urbl->urb = urb;
        urbl->req_id = req_id;
        urbl->ep_num = ep_addr;
        /* Hold lock while we insert the URB into the list within the
         * endpoint structure.
         */
        spin_lock_bh(&port->ozhcd->hcd_lock);
        /* If the urb has been unlinked while out of any list then
         * complete it now.
         */
        if (urb->unlinked) {
                spin_unlock_bh(&port->ozhcd->hcd_lock);
                oz_dbg(ON, "urb %p unlinked so complete immediately\n", urb);
                oz_complete_urb(port->ozhcd->hcd, urb, 0);
                oz_free_urb_link(urbl);
                return 0;
        }

        if (in_dir)
                ep = port->in_ep[ep_addr];
        else
                ep = port->out_ep[ep_addr];
        if (!ep) {
                err = -ENOMEM;
                goto out;
        }

        /*For interrupt endpoint check for buffered data
        * & complete urb
        */
        if (((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)
                                                 && ep->buffered_units > 0) {
                oz_free_urb_link(urbl);
                spin_unlock_bh(&port->ozhcd->hcd_lock);
                oz_complete_buffered_urb(port, ep, urb);
                return 0;
        }

        if (port->hpd) {
                list_add_tail(&urbl->link, &ep->urb_list);
                if (!in_dir && ep_addr && (ep->credit < 0)) {
                        getrawmonotonic(&ep->timestamp);
                        ep->credit = 0;
                }
        } else {
                err = -EPIPE;
        }
out:
        spin_unlock_bh(&port->ozhcd->hcd_lock);
        if (err)
                oz_free_urb_link(urbl);
        return err;
}

/*
 * Removes an urb from the queue in the endpoint.
 * Returns 0 if it is found and -EIDRM otherwise.
 * Context: softirq
 */
static int oz_dequeue_ep_urb(struct oz_port *port, u8 ep_addr, int in_dir,
                        struct urb *urb)
{
        struct oz_urb_link *urbl = NULL;
        struct oz_endpoint *ep;

        spin_lock_bh(&port->ozhcd->hcd_lock);
        if (in_dir)
                ep = port->in_ep[ep_addr];
        else
                ep = port->out_ep[ep_addr];
        if (ep) {
                struct list_head *e;
                list_for_each(e, &ep->urb_list) {
                        urbl = container_of(e, struct oz_urb_link, link);
                        if (urbl->urb == urb) {
                                list_del_init(e);
                                break;
                        }
                        urbl = NULL;
                }
        }
        spin_unlock_bh(&port->ozhcd->hcd_lock);
        if (urbl)
                oz_free_urb_link(urbl);
        return urbl ? 0 : -EIDRM;
}

/*
 * Finds an urb given its request id.
 * Context: softirq
 */
static struct urb *oz_find_urb_by_id(struct oz_port *port, int ep_ix,
                u8 req_id)
{
        struct oz_hcd *ozhcd = port->ozhcd;
        struct urb *urb = NULL;
        struct oz_urb_link *urbl;
        struct oz_endpoint *ep;

        spin_lock_bh(&ozhcd->hcd_lock);
        ep = port->out_ep[ep_ix];
        if (ep) {
                struct list_head *e;
                list_for_each(e, &ep->urb_list) {
                        urbl = container_of(e, struct oz_urb_link, link);
                        if (urbl->req_id == req_id) {
                                urb = urbl->urb;
                                list_del_init(e);
                                break;
                        }
                }
        }
        spin_unlock_bh(&ozhcd->hcd_lock);
        /* If urb is non-zero then we we must have an urb link to delete.
         */
        if (urb)
                oz_free_urb_link(urbl);
        return urb;
}

/*
 * Pre-condition: Port lock must be held.
 * Context: softirq
 */
static void oz_acquire_port(struct oz_port *port, void *hpd)
{
        INIT_LIST_HEAD(&port->isoc_out_ep);
        INIT_LIST_HEAD(&port->isoc_in_ep);
        port->flags |= OZ_PORT_F_PRESENT | OZ_PORT_F_CHANGED;
        port->status |= USB_PORT_STAT_CONNECTION |
                        (USB_PORT_STAT_C_CONNECTION << 16);
        oz_usb_get(hpd);
        port->hpd = hpd;
}

/*
 * Context: softirq
 */
static struct oz_hcd *oz_hcd_claim(void)
{
        struct oz_hcd *ozhcd;

        spin_lock_bh(&g_hcdlock);
        ozhcd = g_ozhcd;
        if (ozhcd)
                usb_get_hcd(ozhcd->hcd);
        spin_unlock_bh(&g_hcdlock);
        return ozhcd;
}

/*
 * Context: softirq
 */
static inline void oz_hcd_put(struct oz_hcd *ozhcd)
{
        if (ozhcd)
                usb_put_hcd(ozhcd->hcd);
}

/*
 * This is called by the protocol handler to notify that a PD has arrived.
 * We allocate a port to associate with the PD and create a structure for
 * endpoint 0. This port is made the connection port.
 * In the event that one of the other port is already a connection port then
 * we fail.
 * TODO We should be able to do better than fail and should be able remember
 * that this port needs configuring and make it the connection port once the
 * current connection port has been assigned an address. Collisions here are
 * probably very rare indeed.
 * Context: softirq
 */
struct oz_port *oz_hcd_pd_arrived(void *hpd)
{
        int i;
        struct oz_port *hport;
        struct oz_hcd *ozhcd;
        struct oz_endpoint *ep;

        ozhcd = oz_hcd_claim();
        if (!ozhcd)
                return NULL;
        /* Allocate an endpoint object in advance (before holding hcd lock) to
         * use for out endpoint 0.
         */
        ep = oz_ep_alloc(0, GFP_ATOMIC);
        if (!ep)
                goto err_put;

        spin_lock_bh(&ozhcd->hcd_lock);
        if (ozhcd->conn_port >= 0)
                goto err_unlock;

        for (i = 0; i < OZ_NB_PORTS; i++) {
                struct oz_port *port = &ozhcd->ports[i];

                spin_lock(&port->port_lock);
                if (!(port->flags & (OZ_PORT_F_PRESENT | OZ_PORT_F_CHANGED))) {
                        oz_acquire_port(port, hpd);
                        spin_unlock(&port->port_lock);
                        break;
                }
                spin_unlock(&port->port_lock);
        }
        if (i == OZ_NB_PORTS)
                goto err_unlock;

        ozhcd->conn_port = i;
        hport = &ozhcd->ports[i];
        hport->out_ep[0] = ep;
        spin_unlock_bh(&ozhcd->hcd_lock);
        if (ozhcd->flags & OZ_HDC_F_SUSPENDED)
                usb_hcd_resume_root_hub(ozhcd->hcd);
        usb_hcd_poll_rh_status(ozhcd->hcd);
        oz_hcd_put(ozhcd);

        return hport;

err_unlock:
        spin_unlock_bh(&ozhcd->hcd_lock);
        oz_ep_free(NULL, ep);
err_put:
        oz_hcd_put(ozhcd);
        return NULL;
}

/*
 * This is called by the protocol handler to notify that the PD has gone away.
 * We need to deallocate all resources and then request that the root hub is
 * polled. We release the reference we hold on the PD.
 * Context: softirq
 */
void oz_hcd_pd_departed(struct oz_port *port)
{
        struct oz_hcd *ozhcd;
        void *hpd;
        struct oz_endpoint *ep = NULL;

        if (port == NULL) {
                oz_dbg(ON, "%s: port = 0\n", __func__);
                return;
        }
        ozhcd = port->ozhcd;
        if (ozhcd == NULL)
                return;
        /* Check if this is the connection port - if so clear it.
         */
        spin_lock_bh(&ozhcd->hcd_lock);
        if ((ozhcd->conn_port >= 0) &&
                (port == &ozhcd->ports[ozhcd->conn_port])) {
                oz_dbg(ON, "Clearing conn_port\n");
                ozhcd->conn_port = -1;
        }
        spin_lock(&port->port_lock);
        port->flags |= OZ_PORT_F_DYING;
        spin_unlock(&port->port_lock);
        spin_unlock_bh(&ozhcd->hcd_lock);

        oz_clean_endpoints_for_config(ozhcd->hcd, port);
        spin_lock_bh(&port->port_lock);
        hpd = port->hpd;
        port->hpd = NULL;
        port->bus_addr = 0xff;
        port->config_num = 0;
        port->flags &= ~(OZ_PORT_F_PRESENT | OZ_PORT_F_DYING);
        port->flags |= OZ_PORT_F_CHANGED;
        port->status &= ~(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE);
        port->status |= (USB_PORT_STAT_C_CONNECTION << 16);
        /* If there is an endpont 0 then clear the pointer while we hold
         * the spinlock be we deallocate it after releasing the lock.
         */
        if (port->out_ep[0]) {
                ep = port->out_ep[0];
                port->out_ep[0] = NULL;
        }
        spin_unlock_bh(&port->port_lock);
        if (ep)
                oz_ep_free(port, ep);
        usb_hcd_poll_rh_status(ozhcd->hcd);
        oz_usb_put(hpd);
}

/*
 * Context: softirq
 */
void oz_hcd_pd_reset(void *hpd, void *hport)
{
        /* Cleanup the current configuration and report reset to the core.
         */
        struct oz_port *port = (struct oz_port *)hport;
        struct oz_hcd *ozhcd = port->ozhcd;

        oz_dbg(ON, "PD Reset\n");
        spin_lock_bh(&port->port_lock);
        port->flags |= OZ_PORT_F_CHANGED;
        port->status |= USB_PORT_STAT_RESET;
        port->status |= (USB_PORT_STAT_C_RESET << 16);
        spin_unlock_bh(&port->port_lock);
        oz_clean_endpoints_for_config(ozhcd->hcd, port);
        usb_hcd_poll_rh_status(ozhcd->hcd);
}

/*
 * Context: softirq
 */
void oz_hcd_get_desc_cnf(void *hport, u8 req_id, int status, const u8 *desc,
                        int length, int offset, int total_size)
{
        struct oz_port *port = (struct oz_port *)hport;
        struct urb *urb;
        int err = 0;

        oz_dbg(ON, "oz_hcd_get_desc_cnf length = %d offs = %d tot_size = %d\n",
               length, offset, total_size);
        urb = oz_find_urb_by_id(port, 0, req_id);
        if (!urb)
                return;
        if (status == 0) {
                int copy_len;
                int required_size = urb->transfer_buffer_length;
                if (required_size > total_size)
                        required_size = total_size;
                copy_len = required_size-offset;
                if (length <= copy_len)
                        copy_len = length;
                memcpy(urb->transfer_buffer+offset, desc, copy_len);
                offset += copy_len;
                if (offset < required_size) {
                        struct usb_ctrlrequest *setup =
                                (struct usb_ctrlrequest *)urb->setup_packet;
                        unsigned wvalue = le16_to_cpu(setup->wValue);
                        if (oz_enqueue_ep_urb(port, 0, 0, urb, req_id))
                                err = -ENOMEM;
                        else if (oz_usb_get_desc_req(port->hpd, req_id,
                                        setup->bRequestType, (u8)(wvalue>>8),
                                        (u8)wvalue, setup->wIndex, offset,
                                        required_size-offset)) {
                                oz_dequeue_ep_urb(port, 0, 0, urb);
                                err = -ENOMEM;
                        }
                        if (err == 0)
                                return;
                }
        }
        urb->actual_length = total_size;
        oz_complete_urb(port->ozhcd->hcd, urb, 0);
}

/*
 * Context: softirq
 */
static void oz_display_conf_type(u8 t)
{
        switch (t) {
        case USB_REQ_GET_STATUS:
                oz_dbg(ON, "USB_REQ_GET_STATUS - cnf\n");
                break;
        case USB_REQ_CLEAR_FEATURE:
                oz_dbg(ON, "USB_REQ_CLEAR_FEATURE - cnf\n");
                break;
        case USB_REQ_SET_FEATURE:
                oz_dbg(ON, "USB_REQ_SET_FEATURE - cnf\n");
                break;
        case USB_REQ_SET_ADDRESS:
                oz_dbg(ON, "USB_REQ_SET_ADDRESS - cnf\n");
                break;
        case USB_REQ_GET_DESCRIPTOR:
                oz_dbg(ON, "USB_REQ_GET_DESCRIPTOR - cnf\n");
                break;
        case USB_REQ_SET_DESCRIPTOR:
                oz_dbg(ON, "USB_REQ_SET_DESCRIPTOR - cnf\n");
                break;
        case USB_REQ_GET_CONFIGURATION:
                oz_dbg(ON, "USB_REQ_GET_CONFIGURATION - cnf\n");
                break;
        case USB_REQ_SET_CONFIGURATION:
                oz_dbg(ON, "USB_REQ_SET_CONFIGURATION - cnf\n");
                break;
        case USB_REQ_GET_INTERFACE:
                oz_dbg(ON, "USB_REQ_GET_INTERFACE - cnf\n");
                break;
        case USB_REQ_SET_INTERFACE:
                oz_dbg(ON, "USB_REQ_SET_INTERFACE - cnf\n");
                break;
        case USB_REQ_SYNCH_FRAME:
                oz_dbg(ON, "USB_REQ_SYNCH_FRAME - cnf\n");
                break;
        }
}

/*
 * Context: softirq
 */
static void oz_hcd_complete_set_config(struct oz_port *port, struct urb *urb,
                u8 rcode, u8 config_num)
{
        int rc = 0;
        struct usb_hcd *hcd = port->ozhcd->hcd;

        if (rcode == 0) {
                port->config_num = config_num;
                oz_clean_endpoints_for_config(hcd, port);
                if (oz_build_endpoints_for_config(hcd, port,
                        &urb->dev->config[port->config_num-1], GFP_ATOMIC)) {
                        rc = -ENOMEM;
                }
        } else {
                rc = -ENOMEM;
        }
        oz_complete_urb(hcd, urb, rc);
}

/*
 * Context: softirq
 */
static void oz_hcd_complete_set_interface(struct oz_port *port, struct urb *urb,
                u8 rcode, u8 if_num, u8 alt)
{
        struct usb_hcd *hcd = port->ozhcd->hcd;
        int rc = 0;

        if ((rcode == 0) && (port->config_num > 0)) {
                struct usb_host_config *config;
                struct usb_host_interface *intf;
                oz_dbg(ON, "Set interface %d alt %d\n", if_num, alt);
                oz_clean_endpoints_for_interface(hcd, port, if_num);
                config = &urb->dev->config[port->config_num-1];
                intf = &config->intf_cache[if_num]->altsetting[alt];
                if (oz_build_endpoints_for_interface(hcd, port, intf,
                        GFP_ATOMIC))
                        rc = -ENOMEM;
                else
                        port->iface[if_num].alt = alt;
        } else {
                rc = -ENOMEM;
        }
        oz_complete_urb(hcd, urb, rc);
}

/*
 * Context: softirq
 */
void oz_hcd_control_cnf(void *hport, u8 req_id, u8 rcode, const u8 *data,
        int data_len)
{
        struct oz_port *port = (struct oz_port *)hport;
        struct urb *urb;
        struct usb_ctrlrequest *setup;
        struct usb_hcd *hcd = port->ozhcd->hcd;
        unsigned windex;
        unsigned wvalue;

        oz_dbg(ON, "oz_hcd_control_cnf rcode=%u len=%d\n", rcode, data_len);
        urb = oz_find_urb_by_id(port, 0, req_id);
        if (!urb) {
                oz_dbg(ON, "URB not found\n");
                return;
        }
        setup = (struct usb_ctrlrequest *)urb->setup_packet;
        windex = le16_to_cpu(setup->wIndex);
        wvalue = le16_to_cpu(setup->wValue);
        if ((setup->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
                /* Standard requests */
                oz_display_conf_type(setup->bRequest);
                switch (setup->bRequest) {
                case USB_REQ_SET_CONFIGURATION:
                        oz_hcd_complete_set_config(port, urb, rcode,
                                (u8)wvalue);
                        break;
                case USB_REQ_SET_INTERFACE:
                        oz_hcd_complete_set_interface(port, urb, rcode,
                                (u8)windex, (u8)wvalue);
                        break;
                default:
                        oz_complete_urb(hcd, urb, 0);
                }

        } else {
                int copy_len;
                oz_dbg(ON, "VENDOR-CLASS - cnf\n");
                if (data_len) {
                        if (data_len <= urb->transfer_buffer_length)
                                copy_len = data_len;
                        else
                                copy_len = urb->transfer_buffer_length;
                        memcpy(urb->transfer_buffer, data, copy_len);
                        urb->actual_length = copy_len;
                }
                oz_complete_urb(hcd, urb, 0);
        }
}

/*
 * Context: softirq-serialized
 */
static int oz_hcd_buffer_data(struct oz_endpoint *ep, const u8 *data,
                              int data_len)
{
        int space;
        int copy_len;

        if (!ep->buffer)
                return -1;
        space = ep->out_ix-ep->in_ix-1;

        if (space < 0)
                space += ep->buffer_size;
        if (space < (data_len+1)) {
                oz_dbg(ON, "Buffer full\n");
                return -1;
        }
        ep->buffer[ep->in_ix] = (u8)data_len;
        if (++ep->in_ix == ep->buffer_size)
                ep->in_ix = 0;
        copy_len = ep->buffer_size - ep->in_ix;
        if (copy_len > data_len)
                copy_len = data_len;
        memcpy(&ep->buffer[ep->in_ix], data, copy_len);

        if (copy_len < data_len) {
                memcpy(ep->buffer, data+copy_len, data_len-copy_len);
                ep->in_ix = data_len-copy_len;
        } else {
                ep->in_ix += copy_len;
        }
        if (ep->in_ix == ep->buffer_size)
                ep->in_ix = 0;
        ep->buffered_units++;
        return 0;
}

/*
 * Context: softirq-serialized
 */
void oz_hcd_data_ind(void *hport, u8 endpoint, const u8 *data, int data_len)
{
        struct oz_port *port = (struct oz_port *)hport;
        struct oz_endpoint *ep;
        struct oz_hcd *ozhcd = port->ozhcd;

        spin_lock_bh(&ozhcd->hcd_lock);
        ep = port->in_ep[endpoint & USB_ENDPOINT_NUMBER_MASK];
        if (ep == NULL)
                goto done;
        switch (ep->attrib & USB_ENDPOINT_XFERTYPE_MASK) {
        case USB_ENDPOINT_XFER_INT:
        case USB_ENDPOINT_XFER_BULK:
                if (!list_empty(&ep->urb_list)) {
                        struct oz_urb_link *urbl =
                                list_first_entry(&ep->urb_list,
                                        struct oz_urb_link, link);
                        struct urb *urb;
                        int copy_len;
                        list_del_init(&urbl->link);
                        spin_unlock_bh(&ozhcd->hcd_lock);
                        urb = urbl->urb;
                        oz_free_urb_link(urbl);
                        if (data_len <= urb->transfer_buffer_length)
                                copy_len = data_len;
                        else
                                copy_len = urb->transfer_buffer_length;
                        memcpy(urb->transfer_buffer, data, copy_len);
                        urb->actual_length = copy_len;
                        oz_complete_urb(port->ozhcd->hcd, urb, 0);
                        return;
                } else {
                        oz_dbg(ON, "buffering frame as URB is not available\n");
                        oz_hcd_buffer_data(ep, data, data_len);
                }
                break;
        case USB_ENDPOINT_XFER_ISOC:
                oz_hcd_buffer_data(ep, data, data_len);
                break;
        }
done:
        spin_unlock_bh(&ozhcd->hcd_lock);
}

/*
 * Context: unknown
 */
static inline int oz_usb_get_frame_number(void)
{
        return atomic_inc_return(&g_usb_frame_number);
}

/*
 * Context: softirq
 */
int oz_hcd_heartbeat(void *hport)
{
        int rc = 0;
        struct oz_port *port = (struct oz_port *)hport;
        struct oz_hcd *ozhcd = port->ozhcd;
        struct oz_urb_link *urbl;
        struct list_head xfr_list;
        struct list_head *e;
        struct list_head *n;
        struct urb *urb;
        struct oz_endpoint *ep;
        struct timespec ts, delta;

        getrawmonotonic(&ts);
        INIT_LIST_HEAD(&xfr_list);
        /* Check the OUT isoc endpoints to see if any URB data can be sent.
         */
        spin_lock_bh(&ozhcd->hcd_lock);
        list_for_each(e, &port->isoc_out_ep) {
                ep = ep_from_link(e);
                if (ep->credit < 0)
                        continue;
                delta = timespec_sub(ts, ep->timestamp);
                ep->credit += div_u64(timespec_to_ns(&delta), NSEC_PER_MSEC);
                if (ep->credit > ep->credit_ceiling)
                        ep->credit = ep->credit_ceiling;
                ep->timestamp = ts;
                while (ep->credit && !list_empty(&ep->urb_list)) {
                        urbl = list_first_entry(&ep->urb_list,
                                struct oz_urb_link, link);
                        urb = urbl->urb;
                        if ((ep->credit + 1) < urb->number_of_packets)
                                break;
                        ep->credit -= urb->number_of_packets;
                        if (ep->credit < 0)
                                ep->credit = 0;
                        list_move_tail(&urbl->link, &xfr_list);
                }
        }
        spin_unlock_bh(&ozhcd->hcd_lock);
        /* Send to PD and complete URBs.
         */
        list_for_each_safe(e, n, &xfr_list) {
                urbl = container_of(e, struct oz_urb_link, link);
                urb = urbl->urb;
                list_del_init(e);
                urb->error_count = 0;
                urb->start_frame = oz_usb_get_frame_number();
                oz_usb_send_isoc(port->hpd, urbl->ep_num, urb);
                oz_free_urb_link(urbl);
                oz_complete_urb(port->ozhcd->hcd, urb, 0);
        }
        /* Check the IN isoc endpoints to see if any URBs can be completed.
         */
        spin_lock_bh(&ozhcd->hcd_lock);
        list_for_each(e, &port->isoc_in_ep) {
                struct oz_endpoint *ep = ep_from_link(e);
                if (ep->flags & OZ_F_EP_BUFFERING) {
                        if (ep->buffered_units >= OZ_IN_BUFFERING_UNITS) {
                                ep->flags &= ~OZ_F_EP_BUFFERING;
                                ep->credit = 0;
                                ep->timestamp = ts;
                                ep->start_frame = 0;
                        }
                        continue;
                }
                delta = timespec_sub(ts, ep->timestamp);
                ep->credit += div_u64(timespec_to_ns(&delta), NSEC_PER_MSEC);
                ep->timestamp = ts;
                while (!list_empty(&ep->urb_list)) {
                        struct oz_urb_link *urbl =
                                list_first_entry(&ep->urb_list,
                                        struct oz_urb_link, link);
                        struct urb *urb = urbl->urb;
                        int len = 0;
                        int copy_len;
                        int i;
                        if (ep->credit  < urb->number_of_packets)
                                break;
                        if (ep->buffered_units < urb->number_of_packets)
                                break;
                        urb->actual_length = 0;
                        for (i = 0; i < urb->number_of_packets; i++) {
                                len = ep->buffer[ep->out_ix];
                                if (++ep->out_ix == ep->buffer_size)
                                        ep->out_ix = 0;
                                copy_len = ep->buffer_size - ep->out_ix;
                                if (copy_len > len)
                                        copy_len = len;
                                memcpy(urb->transfer_buffer,
                                        &ep->buffer[ep->out_ix], copy_len);
                                if (copy_len < len) {
                                        memcpy(urb->transfer_buffer+copy_len,
                                                ep->buffer, len-copy_len);
                                        ep->out_ix = len-copy_len;
                                } else
                                        ep->out_ix += copy_len;
                                if (ep->out_ix == ep->buffer_size)
                                        ep->out_ix = 0;
                                urb->iso_frame_desc[i].offset =
                                        urb->actual_length;
                                urb->actual_length += len;
                                urb->iso_frame_desc[i].actual_length = len;
                                urb->iso_frame_desc[i].status = 0;
                        }
                        ep->buffered_units -= urb->number_of_packets;
                        urb->error_count = 0;
                        urb->start_frame = ep->start_frame;
                        ep->start_frame += urb->number_of_packets;
                        list_move_tail(&urbl->link, &xfr_list);
                        ep->credit -= urb->number_of_packets;
                }
        }
        if (!list_empty(&port->isoc_out_ep) || !list_empty(&port->isoc_in_ep))
                rc = 1;
        spin_unlock_bh(&ozhcd->hcd_lock);
        /* Complete the filled URBs.
         */
        list_for_each_safe(e, n, &xfr_list) {
                urbl = container_of(e, struct oz_urb_link, link);
                urb = urbl->urb;
                list_del_init(e);
                oz_free_urb_link(urbl);
                oz_complete_urb(port->ozhcd->hcd, urb, 0);
        }
        /* Check if there are any ep0 requests that have timed out.
         * If so resent to PD.
         */
        ep = port->out_ep[0];
        if (ep) {
                struct list_head *e;
                struct list_head *n;
                spin_lock_bh(&ozhcd->hcd_lock);
                list_for_each_safe(e, n, &ep->urb_list) {
                        urbl = container_of(e, struct oz_urb_link, link);
                        if (urbl->submit_counter > EP0_TIMEOUT_COUNTER) {
                                oz_dbg(ON, "Request 0x%p timeout\n", urbl->urb);
                                list_move_tail(e, &xfr_list);
                                urbl->submit_counter = 0;
                        } else {
                                urbl->submit_counter++;
                        }
                }
                if (!list_empty(&ep->urb_list))
                        rc = 1;
                spin_unlock_bh(&ozhcd->hcd_lock);
                e = xfr_list.next;
                while (e != &xfr_list) {
                        urbl = container_of(e, struct oz_urb_link, link);
                        e = e->next;
                        oz_dbg(ON, "Resending request to PD\n");
                        oz_process_ep0_urb(ozhcd, urbl->urb, GFP_ATOMIC);
                        oz_free_urb_link(urbl);
                }
        }
        return rc;
}

/*
 * Context: softirq
 */
static int oz_build_endpoints_for_interface(struct usb_hcd *hcd,
                struct oz_port *port,
                struct usb_host_interface *intf, gfp_t mem_flags)
{
        struct oz_hcd *ozhcd = port->ozhcd;
        int i;
        int if_ix = intf->desc.bInterfaceNumber;
        int request_heartbeat = 0;

        oz_dbg(ON, "interface[%d] = %p\n", if_ix, intf);
        if (if_ix >= port->num_iface || port->iface == NULL)
                return -ENOMEM;
        for (i = 0; i < intf->desc.bNumEndpoints; i++) {
                struct usb_host_endpoint *hep = &intf->endpoint[i];
                u8 ep_addr = hep->desc.bEndpointAddress;
                u8 ep_num = ep_addr & USB_ENDPOINT_NUMBER_MASK;
                struct oz_endpoint *ep;
                int buffer_size = 0;

                oz_dbg(ON, "%d bEndpointAddress = %x\n", i, ep_addr);
                if (ep_addr & USB_ENDPOINT_DIR_MASK) {
                        switch (hep->desc.bmAttributes &
                                                USB_ENDPOINT_XFERTYPE_MASK) {
                        case USB_ENDPOINT_XFER_ISOC:
                                buffer_size = OZ_EP_BUFFER_SIZE_ISOC;
                                break;
                        case USB_ENDPOINT_XFER_INT:
                                buffer_size = OZ_EP_BUFFER_SIZE_INT;
                                break;
                        }
                }

                ep = oz_ep_alloc(buffer_size, mem_flags);
                if (!ep) {
                        oz_clean_endpoints_for_interface(hcd, port, if_ix);
                        return -ENOMEM;
                }
                ep->attrib = hep->desc.bmAttributes;
                ep->ep_num = ep_num;
                if ((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK)
                        == USB_ENDPOINT_XFER_ISOC) {
                        oz_dbg(ON, "wMaxPacketSize = %d\n",
                               usb_endpoint_maxp(&hep->desc));
                        ep->credit_ceiling = 200;
                        if (ep_addr & USB_ENDPOINT_DIR_MASK) {
                                ep->flags |= OZ_F_EP_BUFFERING;
                        } else {
                                ep->flags |= OZ_F_EP_HAVE_STREAM;
                                if (oz_usb_stream_create(port->hpd, ep_num))
                                        ep->flags &= ~OZ_F_EP_HAVE_STREAM;
                        }
                }
                spin_lock_bh(&ozhcd->hcd_lock);
                if (ep_addr & USB_ENDPOINT_DIR_MASK) {
                        port->in_ep[ep_num] = ep;
                        port->iface[if_ix].ep_mask |=
                                (1<<(ep_num+OZ_NB_ENDPOINTS));
                        if ((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK)
                                 == USB_ENDPOINT_XFER_ISOC) {
                                list_add_tail(&ep->link, &port->isoc_in_ep);
                                request_heartbeat = 1;
                        }
                } else {
                        port->out_ep[ep_num] = ep;
                        port->iface[if_ix].ep_mask |= (1<<ep_num);
                        if ((ep->attrib & USB_ENDPOINT_XFERTYPE_MASK)
                                == USB_ENDPOINT_XFER_ISOC) {
                                list_add_tail(&ep->link, &port->isoc_out_ep);
                                request_heartbeat = 1;
                        }
                }
                spin_unlock_bh(&ozhcd->hcd_lock);
                if (request_heartbeat && port->hpd)
                        oz_usb_request_heartbeat(port->hpd);
        }
        return 0;
}

/*
 * Context: softirq
 */
static void oz_clean_endpoints_for_interface(struct usb_hcd *hcd,
                        struct oz_port *port, int if_ix)
{
        struct oz_hcd *ozhcd = port->ozhcd;
        unsigned mask;
        int i;
        struct list_head ep_list;

        oz_dbg(ON, "Deleting endpoints for interface %d\n", if_ix);
        if (if_ix >= port->num_iface)
                return;
        INIT_LIST_HEAD(&ep_list);
        spin_lock_bh(&ozhcd->hcd_lock);
        mask = port->iface[if_ix].ep_mask;
        port->iface[if_ix].ep_mask = 0;
        for (i = 0; i < OZ_NB_ENDPOINTS; i++) {
                struct list_head *e;
                /* Gather OUT endpoints.
                 */
                if ((mask & (1<<i)) && port->out_ep[i]) {
                        e = &port->out_ep[i]->link;
                        port->out_ep[i] = NULL;
                        /* Remove from isoc list if present.
                         */
                        list_move_tail(e, &ep_list);
                }
                /* Gather IN endpoints.
                 */
                if ((mask & (1<<(i+OZ_NB_ENDPOINTS))) && port->in_ep[i]) {
                        e = &port->in_ep[i]->link;
                        port->in_ep[i] = NULL;
                        list_move_tail(e, &ep_list);
                }
        }
        spin_unlock_bh(&ozhcd->hcd_lock);
        while (!list_empty(&ep_list)) {
                struct oz_endpoint *ep =
                        list_first_entry(&ep_list, struct oz_endpoint, link);
                list_del_init(&ep->link);
                oz_ep_free(port, ep);
        }
}

/*
 * Context: softirq
 */
static int oz_build_endpoints_for_config(struct usb_hcd *hcd,
                struct oz_port *port, struct usb_host_config *config,
                gfp_t mem_flags)
{
        struct oz_hcd *ozhcd = port->ozhcd;
        int i;
        int num_iface = config->desc.bNumInterfaces;

        if (num_iface) {
                struct oz_interface *iface;

                iface = kmalloc(num_iface*sizeof(struct oz_interface),
                                mem_flags | __GFP_ZERO);
                if (!iface)
                        return -ENOMEM;
                spin_lock_bh(&ozhcd->hcd_lock);
                port->iface = iface;
                port->num_iface = num_iface;
                spin_unlock_bh(&ozhcd->hcd_lock);
        }
        for (i = 0; i < num_iface; i++) {
                struct usb_host_interface *intf =
                        &config->intf_cache[i]->altsetting[0];
                if (oz_build_endpoints_for_interface(hcd, port, intf,
                        mem_flags))
                        goto fail;
        }
        return 0;
fail:
        oz_clean_endpoints_for_config(hcd, port);
        return -1;
}

/*
 * Context: softirq
 */
static void oz_clean_endpoints_for_config(struct usb_hcd *hcd,
                        struct oz_port *port)
{
        struct oz_hcd *ozhcd = port->ozhcd;
        int i;

        oz_dbg(ON, "Deleting endpoints for configuration\n");
        for (i = 0; i < port->num_iface; i++)
                oz_clean_endpoints_for_interface(hcd, port, i);
        spin_lock_bh(&ozhcd->hcd_lock);
        if (port->iface) {
                oz_dbg(ON, "Freeing interfaces object\n");
                kfree(port->iface);
                port->iface = NULL;
        }
        port->num_iface = 0;
        spin_unlock_bh(&ozhcd->hcd_lock);
}

/*
 * Context: tasklet
 */
static void *oz_claim_hpd(struct oz_port *port)
{
        void *hpd;
        struct oz_hcd *ozhcd = port->ozhcd;

        spin_lock_bh(&ozhcd->hcd_lock);
        hpd = port->hpd;
        if (hpd)
                oz_usb_get(hpd);
        spin_unlock_bh(&ozhcd->hcd_lock);
        return hpd;
}

/*
 * Context: tasklet
 */
static void oz_process_ep0_urb(struct oz_hcd *ozhcd, struct urb *urb,
                gfp_t mem_flags)
{
        struct usb_ctrlrequest *setup;
        unsigned windex;
        unsigned wvalue;
        unsigned wlength;
        void *hpd;
        u8 req_id;
        int rc = 0;
        unsigned complete = 0;

        int port_ix = -1;
        struct oz_port *port = NULL;

        oz_dbg(URB, "[%s]:(%p)\n", __func__, urb);
        port_ix = oz_get_port_from_addr(ozhcd, urb->dev->devnum);
        if (port_ix < 0) {
                rc = -EPIPE;
                goto out;
        }
        port =  &ozhcd->ports[port_ix];
        if (((port->flags & OZ_PORT_F_PRESENT) == 0)
                || (port->flags & OZ_PORT_F_DYING)) {
                oz_dbg(ON, "Refusing URB port_ix = %d devnum = %d\n",
                       port_ix, urb->dev->devnum);
                rc = -EPIPE;
                goto out;
        }
        /* Store port in private context data.
         */
        urb->hcpriv = port;
        setup = (struct usb_ctrlrequest *)urb->setup_packet;
        windex = le16_to_cpu(setup->wIndex);
        wvalue = le16_to_cpu(setup->wValue);
        wlength = le16_to_cpu(setup->wLength);
        oz_dbg(CTRL_DETAIL, "bRequestType = %x\n", setup->bRequestType);
        oz_dbg(CTRL_DETAIL, "bRequest = %x\n", setup->bRequest);
        oz_dbg(CTRL_DETAIL, "wValue = %x\n", wvalue);
        oz_dbg(CTRL_DETAIL, "wIndex = %x\n", windex);
        oz_dbg(CTRL_DETAIL, "wLength = %x\n", wlength);

        req_id = port->next_req_id++;
        hpd = oz_claim_hpd(port);
        if (hpd == NULL) {
                oz_dbg(ON, "Cannot claim port\n");
                rc = -EPIPE;
                goto out;
        }

        if ((setup->bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD) {
                /* Standard requests
                 */
                switch (setup->bRequest) {
                case USB_REQ_GET_DESCRIPTOR:
                        oz_dbg(ON, "USB_REQ_GET_DESCRIPTOR - req\n");
                        break;
                case USB_REQ_SET_ADDRESS:
                        oz_dbg(ON, "USB_REQ_SET_ADDRESS - req\n");
                        oz_dbg(ON, "Port %d address is 0x%x\n",
                               ozhcd->conn_port,
                               (u8)le16_to_cpu(setup->wValue));
                        spin_lock_bh(&ozhcd->hcd_lock);
                        if (ozhcd->conn_port >= 0) {
                                ozhcd->ports[ozhcd->conn_port].bus_addr =
                                        (u8)le16_to_cpu(setup->wValue);
                                oz_dbg(ON, "Clearing conn_port\n");
                                ozhcd->conn_port = -1;
                        }
                        spin_unlock_bh(&ozhcd->hcd_lock);
                        complete = 1;
                        break;
                case USB_REQ_SET_CONFIGURATION:
                        oz_dbg(ON, "USB_REQ_SET_CONFIGURATION - req\n");
                        break;
                case USB_REQ_GET_CONFIGURATION:
                        /* We short circuit this case and reply directly since
                         * we have the selected configuration number cached.
                         */
                        oz_dbg(ON, "USB_REQ_GET_CONFIGURATION - reply now\n");
                        if (urb->transfer_buffer_length >= 1) {
                                urb->actual_length = 1;
                                *((u8 *)urb->transfer_buffer) =
                                        port->config_num;
                                complete = 1;
                        } else {
                                rc = -EPIPE;
                        }
                        break;
                case USB_REQ_GET_INTERFACE:
                        /* We short circuit this case and reply directly since
                         * we have the selected interface alternative cached.
                         */
                        oz_dbg(ON, "USB_REQ_GET_INTERFACE - reply now\n");
                        if (urb->transfer_buffer_length >= 1) {
                                urb->actual_length = 1;
                                *((u8 *)urb->transfer_buffer) =
                                        port->iface[(u8)windex].alt;
                                oz_dbg(ON, "interface = %d alt = %d\n",
                                       windex, port->iface[(u8)windex].alt);
                                complete = 1;
                        } else {
                                rc = -EPIPE;
                        }
                        break;
                case USB_REQ_SET_INTERFACE:
                        oz_dbg(ON, "USB_REQ_SET_INTERFACE - req\n");
                        break;
                }
        }
        if (!rc && !complete) {
                int data_len = 0;
                if ((setup->bRequestType & USB_DIR_IN) == 0)
                        data_len = wlength;
                urb->actual_length = data_len;
                if (oz_usb_control_req(port->hpd, req_id, setup,
                                urb->transfer_buffer, data_len)) {
                        rc = -ENOMEM;
                } else {
                        /* Note: we are queuing the request after we have
                         * submitted it to be transmitted. If the request were
                         * to complete before we queued it then it would not
                         * be found in the queue. It seems impossible for
                         * this to happen but if it did the request would
                         * be resubmitted so the problem would hopefully
                         * resolve itself. Putting the request into the
                         * queue before it has been sent is worse since the
                         * urb could be cancelled while we are using it
                         * to build the request.
                         */
                        if (oz_enqueue_ep_urb(port, 0, 0, urb, req_id))
                                rc = -ENOMEM;
                }
        }
        oz_usb_put(hpd);
out:
        if (rc || complete) {
                oz_dbg(ON, "Completing request locally\n");
                oz_complete_urb(ozhcd->hcd, urb, rc);
        } else {
                oz_usb_request_heartbeat(port->hpd);
        }
}

/*
 * Context: tasklet
 */
static int oz_urb_process(struct oz_hcd *ozhcd, struct urb *urb)
{
        int rc = 0;
        struct oz_port *port = urb->hcpriv;
        u8 ep_addr;

        /* When we are paranoid we keep a list of urbs which we check against
         * before handing one back. This is just for debugging during
         * development and should be turned off in the released driver.
         */
        oz_remember_urb(urb);
        /* Check buffer is valid.
         */
        if (!urb->transfer_buffer && urb->transfer_buffer_length)
                return -EINVAL;
        /* Check if there is a device at the port - refuse if not.
         */
        if ((port->flags & OZ_PORT_F_PRESENT) == 0)
                return -EPIPE;
        ep_addr = usb_pipeendpoint(urb->pipe);
        if (ep_addr) {
                /* If the request is not for EP0 then queue it.
                 */
                if (oz_enqueue_ep_urb(port, ep_addr, usb_pipein(urb->pipe),
                        urb, 0))
                        rc = -EPIPE;
        } else {
                oz_process_ep0_urb(ozhcd, urb, GFP_ATOMIC);
        }
        return rc;
}

/*
 * Context: tasklet
 */
static void oz_urb_process_tasklet(unsigned long unused)
{
        unsigned long irq_state;
        struct urb *urb;
        struct oz_hcd *ozhcd = oz_hcd_claim();
        int rc = 0;

        if (ozhcd == NULL)
                return;
        /* This is called from a tasklet so is in softirq context but the urb
         * list is filled from any context so we need to lock
         * appropriately while removing urbs.
         */
        spin_lock_irqsave(&g_tasklet_lock, irq_state);
        while (!list_empty(&ozhcd->urb_pending_list)) {
                struct oz_urb_link *urbl =
                        list_first_entry(&ozhcd->urb_pending_list,
                                struct oz_urb_link, link);
                list_del_init(&urbl->link);
                spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
                urb = urbl->urb;
                oz_free_urb_link(urbl);
                rc = oz_urb_process(ozhcd, urb);
                if (rc)
                        oz_complete_urb(ozhcd->hcd, urb, rc);
                spin_lock_irqsave(&g_tasklet_lock, irq_state);
        }
        spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
        oz_hcd_put(ozhcd);
}

/*
 * This function searches for the urb in any of the lists it could be in.
 * If it is found it is removed from the list and completed. If the urb is
 * being processed then it won't be in a list so won't be found. However, the
 * call to usb_hcd_check_unlink_urb() will set the value of the unlinked field
 * to a non-zero value. When an attempt is made to put the urb back in a list
 * the unlinked field will be checked and the urb will then be completed.
 * Context: tasklet
 */
static void oz_urb_cancel(struct oz_port *port, u8 ep_num, struct urb *urb)
{
        struct oz_urb_link *urbl = NULL;
        struct list_head *e;
        struct oz_hcd *ozhcd;
        unsigned long irq_state;
        u8 ix;

        if (port == NULL) {
                oz_dbg(ON, "%s: ERROR: (%p) port is null\n", __func__, urb);
                return;
        }
        ozhcd = port->ozhcd;
        if (ozhcd == NULL) {
                oz_dbg(ON, "%s; ERROR: (%p) ozhcd is null\n", __func__, urb);
                return;
        }

        /* Look in the tasklet queue.
         */
        spin_lock_irqsave(&g_tasklet_lock, irq_state);
        list_for_each(e, &ozhcd->urb_cancel_list) {
                urbl = container_of(e, struct oz_urb_link, link);
                if (urb == urbl->urb) {
                        list_del_init(e);
                        spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
                        goto out2;
                }
        }
        spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
        urbl = NULL;

        /* Look in the orphanage.
         */
        spin_lock_irqsave(&ozhcd->hcd_lock, irq_state);
        list_for_each(e, &ozhcd->orphanage) {
                urbl = container_of(e, struct oz_urb_link, link);
                if (urbl->urb == urb) {
                        list_del(e);
                        oz_dbg(ON, "Found urb in orphanage\n");
                        goto out;
                }
        }
        ix = (ep_num & 0xf);
        urbl = NULL;
        if ((ep_num & USB_DIR_IN) && ix)
                urbl = oz_remove_urb(port->in_ep[ix], urb);
        else
                urbl = oz_remove_urb(port->out_ep[ix], urb);
out:
        spin_unlock_irqrestore(&ozhcd->hcd_lock, irq_state);
out2:
        if (urbl) {
                urb->actual_length = 0;
                oz_free_urb_link(urbl);
                oz_complete_urb(ozhcd->hcd, urb, -EPIPE);
        }
}

/*
 * Context: tasklet
 */
static void oz_urb_cancel_tasklet(unsigned long unused)
{
        unsigned long irq_state;
        struct urb *urb;
        struct oz_hcd *ozhcd = oz_hcd_claim();

        if (ozhcd == NULL)
                return;
        spin_lock_irqsave(&g_tasklet_lock, irq_state);
        while (!list_empty(&ozhcd->urb_cancel_list)) {
                struct oz_urb_link *urbl =
                        list_first_entry(&ozhcd->urb_cancel_list,
                                struct oz_urb_link, link);
                list_del_init(&urbl->link);
                spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
                urb = urbl->urb;
                if (urb->unlinked)
                        oz_urb_cancel(urbl->port, urbl->ep_num, urb);
                oz_free_urb_link(urbl);
                spin_lock_irqsave(&g_tasklet_lock, irq_state);
        }
        spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
        oz_hcd_put(ozhcd);
}

/*
 * Context: unknown
 */
static void oz_hcd_clear_orphanage(struct oz_hcd *ozhcd, int status)
{
        if (ozhcd) {
                struct oz_urb_link *urbl;
                while (!list_empty(&ozhcd->orphanage)) {
                        urbl = list_first_entry(&ozhcd->orphanage,
                                struct oz_urb_link, link);
                        list_del(&urbl->link);
                        oz_complete_urb(ozhcd->hcd, urbl->urb, status);
                        oz_free_urb_link(urbl);
                }
        }
}

/*
 * Context: unknown
 */
static int oz_hcd_start(struct usb_hcd *hcd)
{
        hcd->power_budget = 200;
        hcd->state = HC_STATE_RUNNING;
        hcd->uses_new_polling = 1;
        return 0;
}

/*
 * Context: unknown
 */
static void oz_hcd_stop(struct usb_hcd *hcd)
{
}

/*
 * Context: unknown
 */
static void oz_hcd_shutdown(struct usb_hcd *hcd)
{
}

/*
 * Called to queue an urb for the device.
 * This function should return a non-zero error code if it fails the urb but
 * should not call usb_hcd_giveback_urb().
 * Context: any
 */
static int oz_hcd_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
                                gfp_t mem_flags)
{
        struct oz_hcd *ozhcd = oz_hcd_private(hcd);
        int rc;
        int port_ix;
        struct oz_port *port;
        unsigned long irq_state;
        struct oz_urb_link *urbl;

        oz_dbg(URB, "%s: (%p)\n",  __func__, urb);
        if (unlikely(ozhcd == NULL)) {
                oz_dbg(URB, "Refused urb(%p) not ozhcd\n", urb);
                return -EPIPE;
        }
        if (unlikely(hcd->state != HC_STATE_RUNNING)) {
                oz_dbg(URB, "Refused urb(%p) not running\n", urb);
                return -EPIPE;
        }
        port_ix = oz_get_port_from_addr(ozhcd, urb->dev->devnum);
        if (port_ix < 0)
                return -EPIPE;
        port =  &ozhcd->ports[port_ix];
        if (port == NULL)
                return -EPIPE;
        if (!(port->flags & OZ_PORT_F_PRESENT) ||
                                (port->flags & OZ_PORT_F_CHANGED)) {
                oz_dbg(ON, "Refusing URB port_ix = %d devnum = %d\n",
                       port_ix, urb->dev->devnum);
                return -EPIPE;
        }
        urb->hcpriv = port;
        /* Put request in queue for processing by tasklet.
         */
        urbl = oz_alloc_urb_link();
        if (unlikely(urbl == NULL))
                return -ENOMEM;
        urbl->urb = urb;
        spin_lock_irqsave(&g_tasklet_lock, irq_state);
        rc = usb_hcd_link_urb_to_ep(hcd, urb);
        if (unlikely(rc)) {
                spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
                oz_free_urb_link(urbl);
                return rc;
        }
        list_add_tail(&urbl->link, &ozhcd->urb_pending_list);
        spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
        tasklet_schedule(&g_urb_process_tasklet);
        atomic_inc(&g_pending_urbs);
        return 0;
}

/*
 * Context: tasklet
 */
static struct oz_urb_link *oz_remove_urb(struct oz_endpoint *ep,
                                struct urb *urb)
{
        struct oz_urb_link *urbl;
        struct list_head *e;

        if (unlikely(ep == NULL))
                return NULL;
        list_for_each(e, &ep->urb_list) {
                urbl = container_of(e, struct oz_urb_link, link);
                if (urbl->urb == urb) {
                        list_del_init(e);
                        if (usb_pipeisoc(urb->pipe)) {
                                ep->credit -= urb->number_of_packets;
                                if (ep->credit < 0)
                                        ep->credit = 0;
                        }
                        return urbl;
                }
        }
        return NULL;
}

/*
 * Called to dequeue a previously submitted urb for the device.
 * Context: any
 */
static int oz_hcd_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
{
        struct oz_hcd *ozhcd = oz_hcd_private(hcd);
        struct oz_urb_link *urbl;
        int rc;
        unsigned long irq_state;

        oz_dbg(URB, "%s: (%p)\n",  __func__, urb);
        urbl = oz_alloc_urb_link();
        if (unlikely(urbl == NULL))
                return -ENOMEM;
        spin_lock_irqsave(&g_tasklet_lock, irq_state);
        /* The following function checks the urb is still in the queue
         * maintained by the core and that the unlinked field is zero.
         * If both are true the function sets the unlinked field and returns
         * zero. Otherwise it returns an error.
         */
        rc = usb_hcd_check_unlink_urb(hcd, urb, status);
        /* We have to check we haven't completed the urb or are about
         * to complete it. When we do we set hcpriv to 0 so if this has
         * already happened we don't put the urb in the cancel queue.
         */
        if ((rc == 0) && urb->hcpriv) {
                urbl->urb = urb;
                urbl->port = (struct oz_port *)urb->hcpriv;
                urbl->ep_num = usb_pipeendpoint(urb->pipe);
                if (usb_pipein(urb->pipe))
                        urbl->ep_num |= USB_DIR_IN;
                list_add_tail(&urbl->link, &ozhcd->urb_cancel_list);
                spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
                tasklet_schedule(&g_urb_cancel_tasklet);
        } else {
                spin_unlock_irqrestore(&g_tasklet_lock, irq_state);
                oz_free_urb_link(urbl);
        }
        return rc;
}

/*
 * Context: unknown
 */
static void oz_hcd_endpoint_disable(struct usb_hcd *hcd,
                                struct usb_host_endpoint *ep)
{
}

/*
 * Context: unknown
 */
static void oz_hcd_endpoint_reset(struct usb_hcd *hcd,
                                struct usb_host_endpoint *ep)
{
}

/*
 * Context: unknown
 */
static int oz_hcd_get_frame_number(struct usb_hcd *hcd)
{
        oz_dbg(ON, "oz_hcd_get_frame_number\n");
        return oz_usb_get_frame_number();
}

/*
 * Context: softirq
 * This is called as a consquence of us calling usb_hcd_poll_rh_status() and we
 * always do that in softirq context.
 */
static int oz_hcd_hub_status_data(struct usb_hcd *hcd, char *buf)
{
        struct oz_hcd *ozhcd = oz_hcd_private(hcd);
        int i;

        buf[0] = 0;
        buf[1] = 0;

        spin_lock_bh(&ozhcd->hcd_lock);
        for (i = 0; i < OZ_NB_PORTS; i++) {
                if (ozhcd->ports[i].flags & OZ_PORT_F_CHANGED) {
                        oz_dbg(HUB, "Port %d changed\n", i);
                        ozhcd->ports[i].flags &= ~OZ_PORT_F_CHANGED;
                        if (i < 7)
                                buf[0] |= 1 << (i + 1);
                        else
                                buf[1] |= 1 << (i - 7);
                }
        }
        spin_unlock_bh(&ozhcd->hcd_lock);
        if (buf[0] != 0 || buf[1] != 0)
                return 2;
        else
                return 0;
}

/*
 * Context: process
 */
static void oz_get_hub_descriptor(struct usb_hcd *hcd,
                                struct usb_hub_descriptor *desc)
{
        memset(desc, 0, sizeof(*desc));
        desc->bDescriptorType = 0x29;
        desc->bDescLength = 9;
        desc->wHubCharacteristics = (__force __u16)
                        __constant_cpu_to_le16(0x0001);
        desc->bNbrPorts = OZ_NB_PORTS;
}

/*
 * Context: process
 */
static int oz_set_port_feature(struct usb_hcd *hcd, u16 wvalue, u16 windex)
{
        struct oz_port *port;
        int err = 0;

        u8 port_id = (u8)windex;
        struct oz_hcd *ozhcd = oz_hcd_private(hcd);
        unsigned set_bits = 0;
        unsigned clear_bits = 0;

        if ((port_id < 1) || (port_id > OZ_NB_PORTS))
                return -EPIPE;
        port = &ozhcd->ports[port_id-1];
        switch (wvalue) {
        case USB_PORT_FEAT_CONNECTION:
                oz_dbg(HUB, "USB_PORT_FEAT_CONNECTION\n");
                break;
        case USB_PORT_FEAT_ENABLE:
                oz_dbg(HUB, "USB_PORT_FEAT_ENABLE\n");
                break;
        case USB_PORT_FEAT_SUSPEND:
                oz_dbg(HUB, "USB_PORT_FEAT_SUSPEND\n");
                break;
        case USB_PORT_FEAT_OVER_CURRENT:
                oz_dbg(HUB, "USB_PORT_FEAT_OVER_CURRENT\n");
                break;
        case USB_PORT_FEAT_RESET:
                oz_dbg(HUB, "USB_PORT_FEAT_RESET\n");
                set_bits = USB_PORT_STAT_ENABLE | (USB_PORT_STAT_C_RESET<<16);
                clear_bits = USB_PORT_STAT_RESET;
                ozhcd->ports[port_id-1].bus_addr = 0;
                break;
        case USB_PORT_FEAT_POWER:
                oz_dbg(HUB, "USB_PORT_FEAT_POWER\n");
                set_bits |= USB_PORT_STAT_POWER;
                break;
        case USB_PORT_FEAT_LOWSPEED:
                oz_dbg(HUB, "USB_PORT_FEAT_LOWSPEED\n");
                break;
        case USB_PORT_FEAT_C_CONNECTION:
                oz_dbg(HUB, "USB_PORT_FEAT_C_CONNECTION\n");
                break;
        case USB_PORT_FEAT_C_ENABLE:
                oz_dbg(HUB, "USB_PORT_FEAT_C_ENABLE\n");
                break;
        case USB_PORT_FEAT_C_SUSPEND:
                oz_dbg(HUB, "USB_PORT_FEAT_C_SUSPEND\n");
                break;
        case USB_PORT_FEAT_C_OVER_CURRENT:
                oz_dbg(HUB, "USB_PORT_FEAT_C_OVER_CURRENT\n");
                break;
        case USB_PORT_FEAT_C_RESET:
                oz_dbg(HUB, "USB_PORT_FEAT_C_RESET\n");
                break;
        case USB_PORT_FEAT_TEST:
                oz_dbg(HUB, "USB_PORT_FEAT_TEST\n");
                break;
        case USB_PORT_FEAT_INDICATOR:
                oz_dbg(HUB, "USB_PORT_FEAT_INDICATOR\n");
                break;
        default:
                oz_dbg(HUB, "Other %d\n", wvalue);
                break;
        }
        if (set_bits || clear_bits) {
                spin_lock_bh(&port->port_lock);
                port->status &= ~clear_bits;
                port->status |= set_bits;
                spin_unlock_bh(&port->port_lock);
        }
        oz_dbg(HUB, "Port[%d] status = 0x%x\n", port_id, port->status);
        return err;
}

/*
 * Context: process
 */
static int oz_clear_port_feature(struct usb_hcd *hcd, u16 wvalue, u16 windex)
{
        struct oz_port *port;
        int err = 0;
        u8 port_id = (u8)windex;
        struct oz_hcd *ozhcd = oz_hcd_private(hcd);
        unsigned clear_bits = 0;

        if ((port_id < 1) || (port_id > OZ_NB_PORTS))
                return -EPIPE;
        port = &ozhcd->ports[port_id-1];
        switch (wvalue) {
        case USB_PORT_FEAT_CONNECTION:
                oz_dbg(HUB, "USB_PORT_FEAT_CONNECTION\n");
                break;
        case USB_PORT_FEAT_ENABLE:
                oz_dbg(HUB, "USB_PORT_FEAT_ENABLE\n");
                clear_bits = USB_PORT_STAT_ENABLE;
                break;
        case USB_PORT_FEAT_SUSPEND:
                oz_dbg(HUB, "USB_PORT_FEAT_SUSPEND\n");
                break;
        case USB_PORT_FEAT_OVER_CURRENT:
                oz_dbg(HUB, "USB_PORT_FEAT_OVER_CURRENT\n");
                break;
        case USB_PORT_FEAT_RESET:
                oz_dbg(HUB, "USB_PORT_FEAT_RESET\n");
                break;
        case USB_PORT_FEAT_POWER:
                oz_dbg(HUB, "USB_PORT_FEAT_POWER\n");
                clear_bits |= USB_PORT_STAT_POWER;
                break;
        case USB_PORT_FEAT_LOWSPEED:
                oz_dbg(HUB, "USB_PORT_FEAT_LOWSPEED\n");
                break;
        case USB_PORT_FEAT_C_CONNECTION:
                oz_dbg(HUB, "USB_PORT_FEAT_C_CONNECTION\n");
                clear_bits = (USB_PORT_STAT_C_CONNECTION << 16);
                break;
        case USB_PORT_FEAT_C_ENABLE:
                oz_dbg(HUB, "USB_PORT_FEAT_C_ENABLE\n");
                clear_bits = (USB_PORT_STAT_C_ENABLE << 16);
                break;
        case USB_PORT_FEAT_C_SUSPEND:
                oz_dbg(HUB, "USB_PORT_FEAT_C_SUSPEND\n");
                break;
        case USB_PORT_FEAT_C_OVER_CURRENT:
                oz_dbg(HUB, "USB_PORT_FEAT_C_OVER_CURRENT\n");
                break;
        case USB_PORT_FEAT_C_RESET:
                oz_dbg(HUB, "USB_PORT_FEAT_C_RESET\n");
                clear_bits = (USB_PORT_FEAT_C_RESET << 16);
                break;
        case USB_PORT_FEAT_TEST:
                oz_dbg(HUB, "USB_PORT_FEAT_TEST\n");
                break;
        case USB_PORT_FEAT_INDICATOR:
                oz_dbg(HUB, "USB_PORT_FEAT_INDICATOR\n");
                break;
        default:
                oz_dbg(HUB, "Other %d\n", wvalue);
                break;
        }
        if (clear_bits) {
                spin_lock_bh(&port->port_lock);
                port->status &= ~clear_bits;
                spin_unlock_bh(&port->port_lock);
        }
        oz_dbg(HUB, "Port[%d] status = 0x%x\n",
               port_id, ozhcd->ports[port_id-1].status);
        return err;
}

/*
 * Context: process
 */
static int oz_get_port_status(struct usb_hcd *hcd, u16 windex, char *buf)
{
        struct oz_hcd *ozhcd;
        u32 status;

        if ((windex < 1) || (windex > OZ_NB_PORTS))
                return -EPIPE;
        ozhcd = oz_hcd_private(hcd);
        oz_dbg(HUB, "GetPortStatus windex = %d\n", windex);
        status = ozhcd->ports[windex-1].status;
        put_unaligned(cpu_to_le32(status), (__le32 *)buf);
        oz_dbg(HUB, "Port[%d] status = %x\n", windex, status);
        return 0;
}

/*
 * Context: process
 */
static int oz_hcd_hub_control(struct usb_hcd *hcd, u16 req_type, u16 wvalue,
                                u16 windex, char *buf, u16 wlength)
{
        int err = 0;

        switch (req_type) {
        case ClearHubFeature:
                oz_dbg(HUB, "ClearHubFeature: %d\n", req_type);
                break;
        case ClearPortFeature:
                err = oz_clear_port_feature(hcd, wvalue, windex);
                break;
        case GetHubDescriptor:
                oz_get_hub_descriptor(hcd, (struct usb_hub_descriptor *)buf);
                break;
        case GetHubStatus:
                oz_dbg(HUB, "GetHubStatus: req_type = 0x%x\n", req_type);
                put_unaligned(__constant_cpu_to_le32(0), (__le32 *)buf);
                break;
        case GetPortStatus:
                err = oz_get_port_status(hcd, windex, buf);
                break;
        case SetHubFeature:
                oz_dbg(HUB, "SetHubFeature: %d\n", req_type);
                break;
        case SetPortFeature:
                err = oz_set_port_feature(hcd, wvalue, windex);
                break;
        default:
                oz_dbg(HUB, "Other: %d\n", req_type);
                break;
        }
        return err;
}

/*
 * Context: process
 */
static int oz_hcd_bus_suspend(struct usb_hcd *hcd)
{
        struct oz_hcd *ozhcd;

        ozhcd = oz_hcd_private(hcd);
        spin_lock_bh(&ozhcd->hcd_lock);
        hcd->state = HC_STATE_SUSPENDED;
        ozhcd->flags |= OZ_HDC_F_SUSPENDED;
        spin_unlock_bh(&ozhcd->hcd_lock);
        return 0;
}

/*
 * Context: process
 */
static int oz_hcd_bus_resume(struct usb_hcd *hcd)
{
        struct oz_hcd *ozhcd;

        ozhcd = oz_hcd_private(hcd);
        spin_lock_bh(&ozhcd->hcd_lock);
        ozhcd->flags &= ~OZ_HDC_F_SUSPENDED;
        hcd->state = HC_STATE_RUNNING;
        spin_unlock_bh(&ozhcd->hcd_lock);
        return 0;
}

static void oz_plat_shutdown(struct platform_device *dev)
{
}

/*
 * Context: process
 */
static int oz_plat_probe(struct platform_device *dev)
{
        int i;
        int err;
        struct usb_hcd *hcd;
        struct oz_hcd *ozhcd;

        hcd = usb_create_hcd(&g_oz_hc_drv, &dev->dev, dev_name(&dev->dev));
        if (hcd == NULL) {
                oz_dbg(ON, "Failed to created hcd object OK\n");
                return -ENOMEM;
        }
        ozhcd = oz_hcd_private(hcd);
        memset(ozhcd, 0, sizeof(*ozhcd));
        INIT_LIST_HEAD(&ozhcd->urb_pending_list);
        INIT_LIST_HEAD(&ozhcd->urb_cancel_list);
        INIT_LIST_HEAD(&ozhcd->orphanage);
        ozhcd->hcd = hcd;
        ozhcd->conn_port = -1;
        spin_lock_init(&ozhcd->hcd_lock);
        for (i = 0; i < OZ_NB_PORTS; i++) {
                struct oz_port *port = &ozhcd->ports[i];
                port->ozhcd = ozhcd;
                port->flags = 0;
                port->status = 0;
                port->bus_addr = 0xff;
                spin_lock_init(&port->port_lock);
        }
        err = usb_add_hcd(hcd, 0, 0);
        if (err) {
                oz_dbg(ON, "Failed to add hcd object OK\n");
                usb_put_hcd(hcd);
                return -1;
        }
        spin_lock_bh(&g_hcdlock);
        g_ozhcd = ozhcd;
        spin_unlock_bh(&g_hcdlock);
        return 0;
}

/*
 * Context: unknown
 */
static int oz_plat_remove(struct platform_device *dev)
{
        struct usb_hcd *hcd = platform_get_drvdata(dev);
        struct oz_hcd *ozhcd;

        if (hcd == NULL)
                return -1;
        ozhcd = oz_hcd_private(hcd);
        spin_lock_bh(&g_hcdlock);
        if (ozhcd == g_ozhcd)
                g_ozhcd = NULL;
        spin_unlock_bh(&g_hcdlock);
        oz_dbg(ON, "Clearing orphanage\n");
        oz_hcd_clear_orphanage(ozhcd, -EPIPE);
        oz_dbg(ON, "Removing hcd\n");
        usb_remove_hcd(hcd);
        usb_put_hcd(hcd);
        oz_empty_link_pool();
        return 0;
}

/*
 * Context: unknown
 */
static int oz_plat_suspend(struct platform_device *dev, pm_message_t msg)
{
        return 0;
}


/*
 * Context: unknown
 */
static int oz_plat_resume(struct platform_device *dev)
{
        return 0;
}

/*
 * Context: process
 */
int oz_hcd_init(void)
{
        int err;

        if (usb_disabled())
                return -ENODEV;
        tasklet_init(&g_urb_process_tasklet, oz_urb_process_tasklet, 0);
        tasklet_init(&g_urb_cancel_tasklet, oz_urb_cancel_tasklet, 0);
        err = platform_driver_register(&g_oz_plat_drv);
        oz_dbg(ON, "platform_driver_register() returned %d\n", err);
        if (err)
                goto error;
        g_plat_dev = platform_device_alloc(OZ_PLAT_DEV_NAME, -1);
        if (g_plat_dev == NULL) {
                err = -ENOMEM;
                goto error1;
        }
        oz_dbg(ON, "platform_device_alloc() succeeded\n");
        err = platform_device_add(g_plat_dev);
        if (err)
                goto error2;
        oz_dbg(ON, "platform_device_add() succeeded\n");
        return 0;
error2:
        platform_device_put(g_plat_dev);
error1:
        platform_driver_unregister(&g_oz_plat_drv);
error:
        tasklet_disable(&g_urb_process_tasklet);
        tasklet_disable(&g_urb_cancel_tasklet);
        oz_dbg(ON, "oz_hcd_init() failed %d\n", err);
        return err;
}

/*
 * Context: process
 */
void oz_hcd_term(void)
{
        msleep(OZ_HUB_DEBOUNCE_TIMEOUT);
        tasklet_kill(&g_urb_process_tasklet);
        tasklet_kill(&g_urb_cancel_tasklet);
        platform_device_unregister(g_plat_dev);
        platform_driver_unregister(&g_oz_plat_drv);
        oz_dbg(ON, "Pending urbs:%d\n", atomic_read(&g_pending_urbs));
}