Linux-2.6.12-rc2

[mirror_ubuntu-bionic-kernel.git] / drivers / usb / host / uhci-hcd.c

/*
 * Universal Host Controller Interface driver for USB.
 *
 * Maintainer: Alan Stern <stern@rowland.harvard.edu>
 *
 * (C) Copyright 1999 Linus Torvalds
 * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
 * (C) Copyright 1999 Randy Dunlap
 * (C) Copyright 1999 Georg Acher, acher@in.tum.de
 * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
 * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
 * (C) Copyright 1999 Roman Weissgaerber, weissg@vienna.at
 * (C) Copyright 2000 Yggdrasil Computing, Inc. (port of new PCI interface
 *               support from usb-ohci.c by Adam Richter, adam@yggdrasil.com).
 * (C) Copyright 1999 Gregory P. Smith (from usb-ohci.c)
 * (C) Copyright 2004 Alan Stern, stern@rowland.harvard.edu
 *
 * Intel documents this fairly well, and as far as I know there
 * are no royalties or anything like that, but even so there are
 * people who decided that they want to do the same thing in a
 * completely different way.
 *
 * WARNING! The USB documentation is downright evil. Most of it
 * is just crap, written by a committee. You're better off ignoring
 * most of it, the important stuff is:
 *  - the low-level protocol (fairly simple but lots of small details)
 *  - working around the horridness of the rest
 */

#include <linux/config.h>
#ifdef CONFIG_USB_DEBUG
#define DEBUG
#else
#undef DEBUG
#endif
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/debugfs.h>
#include <linux/pm.h>
#include <linux/dmapool.h>
#include <linux/dma-mapping.h>
#include <linux/usb.h>
#include <linux/bitops.h>

#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>

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

/*
 * Version Information
 */
#define DRIVER_VERSION "v2.2"
#define DRIVER_AUTHOR "Linus 'Frodo Rabbit' Torvalds, Johannes Erdfelt, \
Randy Dunlap, Georg Acher, Deti Fliegl, Thomas Sailer, Roman Weissgaerber, \
Alan Stern"
#define DRIVER_DESC "USB Universal Host Controller Interface driver"

/*
 * debug = 0, no debugging messages
 * debug = 1, dump failed URB's except for stalls
 * debug = 2, dump all failed URB's (including stalls)
 *            show all queues in /debug/uhci/[pci_addr]
 * debug = 3, show all TD's in URB's when dumping
 */
#ifdef DEBUG
static int debug = 1;
#else
static int debug = 0;
#endif
module_param(debug, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug level");
static char *errbuf;
#define ERRBUF_LEN    (32 * 1024)

static kmem_cache_t *uhci_up_cachep;    /* urb_priv */

static void uhci_get_current_frame_number(struct uhci_hcd *uhci);
static void hc_state_transitions(struct uhci_hcd *uhci);

/* If a transfer is still active after this much time, turn off FSBR */
#define IDLE_TIMEOUT    msecs_to_jiffies(50)
#define FSBR_DELAY      msecs_to_jiffies(50)

/* When we timeout an idle transfer for FSBR, we'll switch it over to */
/* depth first traversal. We'll do it in groups of this number of TD's */
/* to make sure it doesn't hog all of the bandwidth */
#define DEPTH_INTERVAL 5

#include "uhci-hub.c"
#include "uhci-debug.c"
#include "uhci-q.c"

static int init_stall_timer(struct usb_hcd *hcd);

static void stall_callback(unsigned long ptr)
{
        struct usb_hcd *hcd = (struct usb_hcd *)ptr;
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);
        struct urb_priv *up;
        unsigned long flags;

        spin_lock_irqsave(&uhci->lock, flags);
        uhci_scan_schedule(uhci, NULL);

        list_for_each_entry(up, &uhci->urb_list, urb_list) {
                struct urb *u = up->urb;

                spin_lock(&u->lock);

                /* Check if the FSBR timed out */
                if (up->fsbr && !up->fsbr_timeout && time_after_eq(jiffies, up->fsbrtime + IDLE_TIMEOUT))
                        uhci_fsbr_timeout(uhci, u);

                spin_unlock(&u->lock);
        }

        /* Really disable FSBR */
        if (!uhci->fsbr && uhci->fsbrtimeout && time_after_eq(jiffies, uhci->fsbrtimeout)) {
                uhci->fsbrtimeout = 0;
                uhci->skel_term_qh->link = UHCI_PTR_TERM;
        }

        /* Poll for and perform state transitions */
        hc_state_transitions(uhci);
        if (unlikely(uhci->suspended_ports && uhci->state != UHCI_SUSPENDED))
                uhci_check_ports(uhci);

        init_stall_timer(hcd);
        spin_unlock_irqrestore(&uhci->lock, flags);
}

static int init_stall_timer(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        init_timer(&uhci->stall_timer);
        uhci->stall_timer.function = stall_callback;
        uhci->stall_timer.data = (unsigned long)hcd;
        uhci->stall_timer.expires = jiffies + msecs_to_jiffies(100);
        add_timer(&uhci->stall_timer);

        return 0;
}

static irqreturn_t uhci_irq(struct usb_hcd *hcd, struct pt_regs *regs)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);
        unsigned long io_addr = uhci->io_addr;
        unsigned short status;

        /*
         * Read the interrupt status, and write it back to clear the
         * interrupt cause.  Contrary to the UHCI specification, the
         * "HC Halted" status bit is persistent: it is RO, not R/WC.
         */
        status = inw(io_addr + USBSTS);
        if (!(status & ~USBSTS_HCH))    /* shared interrupt, not mine */
                return IRQ_NONE;
        outw(status, io_addr + USBSTS);         /* Clear it */

        if (status & ~(USBSTS_USBINT | USBSTS_ERROR | USBSTS_RD)) {
                if (status & USBSTS_HSE)
                        dev_err(uhci_dev(uhci), "host system error, "
                                        "PCI problems?\n");
                if (status & USBSTS_HCPE)
                        dev_err(uhci_dev(uhci), "host controller process "
                                        "error, something bad happened!\n");
                if ((status & USBSTS_HCH) && uhci->state > 0) {
                        dev_err(uhci_dev(uhci), "host controller halted, "
                                        "very bad!\n");
                        /* FIXME: Reset the controller, fix the offending TD */
                }
        }

        if (status & USBSTS_RD)
                uhci->resume_detect = 1;

        spin_lock(&uhci->lock);
        uhci_scan_schedule(uhci, regs);
        spin_unlock(&uhci->lock);

        return IRQ_HANDLED;
}

static void reset_hc(struct uhci_hcd *uhci)
{
        unsigned long io_addr = uhci->io_addr;

        /* Turn off PIRQ, SMI, and all interrupts.  This also turns off
         * the BIOS's USB Legacy Support.
         */
        pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP, 0);
        outw(0, uhci->io_addr + USBINTR);

        /* Global reset for 50ms */
        uhci->state = UHCI_RESET;
        outw(USBCMD_GRESET, io_addr + USBCMD);
        msleep(50);
        outw(0, io_addr + USBCMD);

        /* Another 10ms delay */
        msleep(10);
        uhci->resume_detect = 0;
        uhci->is_stopped = UHCI_IS_STOPPED;
}

static void suspend_hc(struct uhci_hcd *uhci)
{
        unsigned long io_addr = uhci->io_addr;

        dev_dbg(uhci_dev(uhci), "%s\n", __FUNCTION__);
        uhci->state = UHCI_SUSPENDED;
        uhci->resume_detect = 0;
        outw(USBCMD_EGSM, io_addr + USBCMD);

        /* FIXME: Wait for the controller to actually stop */
        uhci_get_current_frame_number(uhci);
        uhci->is_stopped = UHCI_IS_STOPPED;

        uhci_scan_schedule(uhci, NULL);
}

static void wakeup_hc(struct uhci_hcd *uhci)
{
        unsigned long io_addr = uhci->io_addr;

        switch (uhci->state) {
                case UHCI_SUSPENDED:            /* Start the resume */
                        dev_dbg(uhci_dev(uhci), "%s\n", __FUNCTION__);

                        /* Global resume for >= 20ms */
                        outw(USBCMD_FGR | USBCMD_EGSM, io_addr + USBCMD);
                        uhci->state = UHCI_RESUMING_1;
                        uhci->state_end = jiffies + msecs_to_jiffies(20);
                        uhci->is_stopped = 0;
                        break;

                case UHCI_RESUMING_1:           /* End global resume */
                        uhci->state = UHCI_RESUMING_2;
                        outw(0, io_addr + USBCMD);
                        /* Falls through */

                case UHCI_RESUMING_2:           /* Wait for EOP to be sent */
                        if (inw(io_addr + USBCMD) & USBCMD_FGR)
                                break;

                        /* Run for at least 1 second, and
                         * mark it configured with a 64-byte max packet */
                        uhci->state = UHCI_RUNNING_GRACE;
                        uhci->state_end = jiffies + HZ;
                        outw(USBCMD_RS | USBCMD_CF | USBCMD_MAXP,
                                        io_addr + USBCMD);
                        break;

                case UHCI_RUNNING_GRACE:        /* Now allowed to suspend */
                        uhci->state = UHCI_RUNNING;
                        break;

                default:
                        break;
        }
}

static int ports_active(struct uhci_hcd *uhci)
{
        unsigned long io_addr = uhci->io_addr;
        int connection = 0;
        int i;

        for (i = 0; i < uhci->rh_numports; i++)
                connection |= (inw(io_addr + USBPORTSC1 + i * 2) & USBPORTSC_CCS);

        return connection;
}

static int suspend_allowed(struct uhci_hcd *uhci)
{
        unsigned long io_addr = uhci->io_addr;
        int i;

        if (to_pci_dev(uhci_dev(uhci))->vendor != PCI_VENDOR_ID_INTEL)
                return 1;

        /* Some of Intel's USB controllers have a bug that causes false
         * resume indications if any port has an over current condition.
         * To prevent problems, we will not allow a global suspend if
         * any ports are OC.
         *
         * Some motherboards using Intel's chipsets (but not using all
         * the USB ports) appear to hardwire the over current inputs active
         * to disable the USB ports.
         */

        /* check for over current condition on any port */
        for (i = 0; i < uhci->rh_numports; i++) {
                if (inw(io_addr + USBPORTSC1 + i * 2) & USBPORTSC_OC)
                        return 0;
        }

        return 1;
}

static void hc_state_transitions(struct uhci_hcd *uhci)
{
        switch (uhci->state) {
                case UHCI_RUNNING:

                        /* global suspend if nothing connected for 1 second */
                        if (!ports_active(uhci) && suspend_allowed(uhci)) {
                                uhci->state = UHCI_SUSPENDING_GRACE;
                                uhci->state_end = jiffies + HZ;
                        }
                        break;

                case UHCI_SUSPENDING_GRACE:
                        if (ports_active(uhci))
                                uhci->state = UHCI_RUNNING;
                        else if (time_after_eq(jiffies, uhci->state_end))
                                suspend_hc(uhci);
                        break;

                case UHCI_SUSPENDED:

                        /* wakeup if requested by a device */
                        if (uhci->resume_detect)
                                wakeup_hc(uhci);
                        break;

                case UHCI_RESUMING_1:
                case UHCI_RESUMING_2:
                case UHCI_RUNNING_GRACE:
                        if (time_after_eq(jiffies, uhci->state_end))
                                wakeup_hc(uhci);
                        break;

                default:
                        break;
        }
}

/*
 * Store the current frame number in uhci->frame_number if the controller
 * is runnning
 */
static void uhci_get_current_frame_number(struct uhci_hcd *uhci)
{
        if (!uhci->is_stopped)
                uhci->frame_number = inw(uhci->io_addr + USBFRNUM);
}

static int start_hc(struct uhci_hcd *uhci)
{
        unsigned long io_addr = uhci->io_addr;
        int timeout = 10;

        /*
         * Reset the HC - this will force us to get a
         * new notification of any already connected
         * ports due to the virtual disconnect that it
         * implies.
         */
        outw(USBCMD_HCRESET, io_addr + USBCMD);
        while (inw(io_addr + USBCMD) & USBCMD_HCRESET) {
                if (--timeout < 0) {
                        dev_err(uhci_dev(uhci), "USBCMD_HCRESET timed out!\n");
                        return -ETIMEDOUT;
                }
                msleep(1);
        }

        /* Mark controller as running before we enable interrupts */
        uhci_to_hcd(uhci)->state = HC_STATE_RUNNING;

        /* Turn on PIRQ and all interrupts */
        pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP,
                        USBLEGSUP_DEFAULT);
        outw(USBINTR_TIMEOUT | USBINTR_RESUME | USBINTR_IOC | USBINTR_SP,
                io_addr + USBINTR);

        /* Start at frame 0 */
        outw(0, io_addr + USBFRNUM);
        outl(uhci->fl->dma_handle, io_addr + USBFLBASEADD);

        /* Run and mark it configured with a 64-byte max packet */
        uhci->state = UHCI_RUNNING_GRACE;
        uhci->state_end = jiffies + HZ;
        outw(USBCMD_RS | USBCMD_CF | USBCMD_MAXP, io_addr + USBCMD);
        uhci->is_stopped = 0;

        return 0;
}

/*
 * De-allocate all resources
 */
static void release_uhci(struct uhci_hcd *uhci)
{
        int i;

        for (i = 0; i < UHCI_NUM_SKELQH; i++)
                if (uhci->skelqh[i]) {
                        uhci_free_qh(uhci, uhci->skelqh[i]);
                        uhci->skelqh[i] = NULL;
                }

        if (uhci->term_td) {
                uhci_free_td(uhci, uhci->term_td);
                uhci->term_td = NULL;
        }

        if (uhci->qh_pool) {
                dma_pool_destroy(uhci->qh_pool);
                uhci->qh_pool = NULL;
        }

        if (uhci->td_pool) {
                dma_pool_destroy(uhci->td_pool);
                uhci->td_pool = NULL;
        }

        if (uhci->fl) {
                dma_free_coherent(uhci_dev(uhci), sizeof(*uhci->fl),
                                uhci->fl, uhci->fl->dma_handle);
                uhci->fl = NULL;
        }

        if (uhci->dentry) {
                debugfs_remove(uhci->dentry);
                uhci->dentry = NULL;
        }
}

static int uhci_reset(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        uhci->io_addr = (unsigned long) hcd->rsrc_start;

        /* Kick BIOS off this hardware and reset, so we won't get
         * interrupts from any previous setup.
         */
        reset_hc(uhci);
        return 0;
}

/*
 * Allocate a frame list, and then setup the skeleton
 *
 * The hardware doesn't really know any difference
 * in the queues, but the order does matter for the
 * protocols higher up. The order is:
 *
 *  - any isochronous events handled before any
 *    of the queues. We don't do that here, because
 *    we'll create the actual TD entries on demand.
 *  - The first queue is the interrupt queue.
 *  - The second queue is the control queue, split into low- and full-speed
 *  - The third queue is bulk queue.
 *  - The fourth queue is the bandwidth reclamation queue, which loops back
 *    to the full-speed control queue.
 */
static int uhci_start(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);
        int retval = -EBUSY;
        int i, port;
        unsigned io_size;
        dma_addr_t dma_handle;
        struct usb_device *udev;
        struct dentry *dentry;

        io_size = (unsigned) hcd->rsrc_len;

        dentry = debugfs_create_file(hcd->self.bus_name, S_IFREG|S_IRUGO|S_IWUSR, uhci_debugfs_root, uhci, &uhci_debug_operations);
        if (!dentry) {
                dev_err(uhci_dev(uhci), "couldn't create uhci debugfs entry\n");
                retval = -ENOMEM;
                goto err_create_debug_entry;
        }
        uhci->dentry = dentry;

        uhci->fsbr = 0;
        uhci->fsbrtimeout = 0;

        spin_lock_init(&uhci->lock);
        INIT_LIST_HEAD(&uhci->qh_remove_list);

        INIT_LIST_HEAD(&uhci->td_remove_list);

        INIT_LIST_HEAD(&uhci->urb_remove_list);

        INIT_LIST_HEAD(&uhci->urb_list);

        INIT_LIST_HEAD(&uhci->complete_list);

        init_waitqueue_head(&uhci->waitqh);

        uhci->fl = dma_alloc_coherent(uhci_dev(uhci), sizeof(*uhci->fl),
                        &dma_handle, 0);
        if (!uhci->fl) {
                dev_err(uhci_dev(uhci), "unable to allocate "
                                "consistent memory for frame list\n");
                goto err_alloc_fl;
        }

        memset((void *)uhci->fl, 0, sizeof(*uhci->fl));

        uhci->fl->dma_handle = dma_handle;

        uhci->td_pool = dma_pool_create("uhci_td", uhci_dev(uhci),
                        sizeof(struct uhci_td), 16, 0);
        if (!uhci->td_pool) {
                dev_err(uhci_dev(uhci), "unable to create td dma_pool\n");
                goto err_create_td_pool;
        }

        uhci->qh_pool = dma_pool_create("uhci_qh", uhci_dev(uhci),
                        sizeof(struct uhci_qh), 16, 0);
        if (!uhci->qh_pool) {
                dev_err(uhci_dev(uhci), "unable to create qh dma_pool\n");
                goto err_create_qh_pool;
        }

        /* Initialize the root hub */

        /* UHCI specs says devices must have 2 ports, but goes on to say */
        /*  they may have more but give no way to determine how many they */
        /*  have. However, according to the UHCI spec, Bit 7 is always set */
        /*  to 1. So we try to use this to our advantage */
        for (port = 0; port < (io_size - 0x10) / 2; port++) {
                unsigned int portstatus;

                portstatus = inw(uhci->io_addr + 0x10 + (port * 2));
                if (!(portstatus & 0x0080))
                        break;
        }
        if (debug)
                dev_info(uhci_dev(uhci), "detected %d ports\n", port);

        /* This is experimental so anything less than 2 or greater than 8 is */
        /*  something weird and we'll ignore it */
        if (port < 2 || port > UHCI_RH_MAXCHILD) {
                dev_info(uhci_dev(uhci), "port count misdetected? "
                                "forcing to 2 ports\n");
                port = 2;
        }

        uhci->rh_numports = port;

        udev = usb_alloc_dev(NULL, &hcd->self, 0);
        if (!udev) {
                dev_err(uhci_dev(uhci), "unable to allocate root hub\n");
                goto err_alloc_root_hub;
        }

        uhci->term_td = uhci_alloc_td(uhci, udev);
        if (!uhci->term_td) {
                dev_err(uhci_dev(uhci), "unable to allocate terminating TD\n");
                goto err_alloc_term_td;
        }

        for (i = 0; i < UHCI_NUM_SKELQH; i++) {
                uhci->skelqh[i] = uhci_alloc_qh(uhci, udev);
                if (!uhci->skelqh[i]) {
                        dev_err(uhci_dev(uhci), "unable to allocate QH\n");
                        goto err_alloc_skelqh;
                }
        }

        /*
         * 8 Interrupt queues; link all higher int queues to int1,
         * then link int1 to control and control to bulk
         */
        uhci->skel_int128_qh->link =
                        uhci->skel_int64_qh->link =
                        uhci->skel_int32_qh->link =
                        uhci->skel_int16_qh->link =
                        uhci->skel_int8_qh->link =
                        uhci->skel_int4_qh->link =
                        uhci->skel_int2_qh->link =
                        cpu_to_le32(uhci->skel_int1_qh->dma_handle) | UHCI_PTR_QH;
        uhci->skel_int1_qh->link = cpu_to_le32(uhci->skel_ls_control_qh->dma_handle) | UHCI_PTR_QH;

        uhci->skel_ls_control_qh->link = cpu_to_le32(uhci->skel_fs_control_qh->dma_handle) | UHCI_PTR_QH;
        uhci->skel_fs_control_qh->link = cpu_to_le32(uhci->skel_bulk_qh->dma_handle) | UHCI_PTR_QH;
        uhci->skel_bulk_qh->link = cpu_to_le32(uhci->skel_term_qh->dma_handle) | UHCI_PTR_QH;

        /* This dummy TD is to work around a bug in Intel PIIX controllers */
        uhci_fill_td(uhci->term_td, 0, (UHCI_NULL_DATA_SIZE << 21) |
                (0x7f << TD_TOKEN_DEVADDR_SHIFT) | USB_PID_IN, 0);
        uhci->term_td->link = cpu_to_le32(uhci->term_td->dma_handle);

        uhci->skel_term_qh->link = UHCI_PTR_TERM;
        uhci->skel_term_qh->element = cpu_to_le32(uhci->term_td->dma_handle);

        /*
         * Fill the frame list: make all entries point to the proper
         * interrupt queue.
         *
         * The interrupt queues will be interleaved as evenly as possible.
         * There's not much to be done about period-1 interrupts; they have
         * to occur in every frame.  But we can schedule period-2 interrupts
         * in odd-numbered frames, period-4 interrupts in frames congruent
         * to 2 (mod 4), and so on.  This way each frame only has two
         * interrupt QHs, which will help spread out bandwidth utilization.
         */
        for (i = 0; i < UHCI_NUMFRAMES; i++) {
                int irq;

                /*
                 * ffs (Find First bit Set) does exactly what we need:
                 * 1,3,5,...  => ffs = 0 => use skel_int2_qh = skelqh[6],
                 * 2,6,10,... => ffs = 1 => use skel_int4_qh = skelqh[5], etc.
                 * ffs > 6 => not on any high-period queue, so use
                 *      skel_int1_qh = skelqh[7].
                 * Add UHCI_NUMFRAMES to insure at least one bit is set.
                 */
                irq = 6 - (int) __ffs(i + UHCI_NUMFRAMES);
                if (irq < 0)
                        irq = 7;

                /* Only place we don't use the frame list routines */
                uhci->fl->frame[i] = UHCI_PTR_QH |
                                cpu_to_le32(uhci->skelqh[irq]->dma_handle);
        }

        /*
         * Some architectures require a full mb() to enforce completion of
         * the memory writes above before the I/O transfers in start_hc().
         */
        mb();
        if ((retval = start_hc(uhci)) != 0)
                goto err_alloc_skelqh;

        init_stall_timer(hcd);

        udev->speed = USB_SPEED_FULL;

        if (usb_hcd_register_root_hub(udev, hcd) != 0) {
                dev_err(uhci_dev(uhci), "unable to start root hub\n");
                retval = -ENOMEM;
                goto err_start_root_hub;
        }

        return 0;

/*
 * error exits:
 */
err_start_root_hub:
        reset_hc(uhci);

        del_timer_sync(&uhci->stall_timer);

err_alloc_skelqh:
        for (i = 0; i < UHCI_NUM_SKELQH; i++)
                if (uhci->skelqh[i]) {
                        uhci_free_qh(uhci, uhci->skelqh[i]);
                        uhci->skelqh[i] = NULL;
                }

        uhci_free_td(uhci, uhci->term_td);
        uhci->term_td = NULL;

err_alloc_term_td:
        usb_put_dev(udev);

err_alloc_root_hub:
        dma_pool_destroy(uhci->qh_pool);
        uhci->qh_pool = NULL;

err_create_qh_pool:
        dma_pool_destroy(uhci->td_pool);
        uhci->td_pool = NULL;

err_create_td_pool:
        dma_free_coherent(uhci_dev(uhci), sizeof(*uhci->fl),
                        uhci->fl, uhci->fl->dma_handle);
        uhci->fl = NULL;

err_alloc_fl:
        debugfs_remove(uhci->dentry);
        uhci->dentry = NULL;

err_create_debug_entry:
        return retval;
}

static void uhci_stop(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        del_timer_sync(&uhci->stall_timer);
        reset_hc(uhci);

        spin_lock_irq(&uhci->lock);
        uhci_scan_schedule(uhci, NULL);
        spin_unlock_irq(&uhci->lock);
        
        release_uhci(uhci);
}

#ifdef CONFIG_PM
static int uhci_suspend(struct usb_hcd *hcd, u32 state)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        spin_lock_irq(&uhci->lock);

        /* Don't try to suspend broken motherboards, reset instead */
        if (suspend_allowed(uhci))
                suspend_hc(uhci);
        else {
                spin_unlock_irq(&uhci->lock);
                reset_hc(uhci);
                spin_lock_irq(&uhci->lock);
                uhci_scan_schedule(uhci, NULL);
        }

        spin_unlock_irq(&uhci->lock);
        return 0;
}

static int uhci_resume(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);
        int rc;

        pci_set_master(to_pci_dev(uhci_dev(uhci)));

        spin_lock_irq(&uhci->lock);

        if (uhci->state == UHCI_SUSPENDED) {

                /*
                 * Some systems don't maintain the UHCI register values
                 * during a PM suspend/resume cycle, so reinitialize
                 * the Frame Number, Framelist Base Address, Interrupt
                 * Enable, and Legacy Support registers.
                 */
                pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP,
                                0);
                outw(uhci->frame_number, uhci->io_addr + USBFRNUM);
                outl(uhci->fl->dma_handle, uhci->io_addr + USBFLBASEADD);
                outw(USBINTR_TIMEOUT | USBINTR_RESUME | USBINTR_IOC |
                                USBINTR_SP, uhci->io_addr + USBINTR);
                uhci->resume_detect = 1;
                pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP,
                                USBLEGSUP_DEFAULT);
        } else {
                spin_unlock_irq(&uhci->lock);
                reset_hc(uhci);
                if ((rc = start_hc(uhci)) != 0)
                        return rc;
                spin_lock_irq(&uhci->lock);
        }
        hcd->state = HC_STATE_RUNNING;

        spin_unlock_irq(&uhci->lock);
        return 0;
}
#endif

/* Wait until all the URBs for a particular device/endpoint are gone */
static void uhci_hcd_endpoint_disable(struct usb_hcd *hcd,
                struct usb_host_endpoint *ep)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);

        wait_event_interruptible(uhci->waitqh, list_empty(&ep->urb_list));
}

static int uhci_hcd_get_frame_number(struct usb_hcd *hcd)
{
        struct uhci_hcd *uhci = hcd_to_uhci(hcd);
        int frame_number;
        unsigned long flags;

        /* Minimize latency by avoiding the spinlock */
        local_irq_save(flags);
        rmb();
        frame_number = (uhci->is_stopped ? uhci->frame_number :
                        inw(uhci->io_addr + USBFRNUM));
        local_irq_restore(flags);
        return frame_number;
}

static const char hcd_name[] = "uhci_hcd";

static const struct hc_driver uhci_driver = {
        .description =          hcd_name,
        .product_desc =         "UHCI Host Controller",
        .hcd_priv_size =        sizeof(struct uhci_hcd),

        /* Generic hardware linkage */
        .irq =                  uhci_irq,
        .flags =                HCD_USB11,

        /* Basic lifecycle operations */
        .reset =                uhci_reset,
        .start =                uhci_start,
#ifdef CONFIG_PM
        .suspend =              uhci_suspend,
        .resume =               uhci_resume,
#endif
        .stop =                 uhci_stop,

        .urb_enqueue =          uhci_urb_enqueue,
        .urb_dequeue =          uhci_urb_dequeue,

        .endpoint_disable =     uhci_hcd_endpoint_disable,
        .get_frame_number =     uhci_hcd_get_frame_number,

        .hub_status_data =      uhci_hub_status_data,
        .hub_control =          uhci_hub_control,
};

static const struct pci_device_id uhci_pci_ids[] = { {
        /* handle any USB UHCI controller */
        PCI_DEVICE_CLASS(((PCI_CLASS_SERIAL_USB << 8) | 0x00), ~0),
        .driver_data =  (unsigned long) &uhci_driver,
        }, { /* end: all zeroes */ }
};

MODULE_DEVICE_TABLE(pci, uhci_pci_ids);

static struct pci_driver uhci_pci_driver = {
        .name =         (char *)hcd_name,
        .id_table =     uhci_pci_ids,

        .probe =        usb_hcd_pci_probe,
        .remove =       usb_hcd_pci_remove,

#ifdef  CONFIG_PM
        .suspend =      usb_hcd_pci_suspend,
        .resume =       usb_hcd_pci_resume,
#endif  /* PM */
};
 
static int __init uhci_hcd_init(void)
{
        int retval = -ENOMEM;

        printk(KERN_INFO DRIVER_DESC " " DRIVER_VERSION "\n");

        if (usb_disabled())
                return -ENODEV;

        if (debug) {
                errbuf = kmalloc(ERRBUF_LEN, GFP_KERNEL);
                if (!errbuf)
                        goto errbuf_failed;
        }

        uhci_debugfs_root = debugfs_create_dir("uhci", NULL);
        if (!uhci_debugfs_root)
                goto debug_failed;

        uhci_up_cachep = kmem_cache_create("uhci_urb_priv",
                sizeof(struct urb_priv), 0, 0, NULL, NULL);
        if (!uhci_up_cachep)
                goto up_failed;

        retval = pci_register_driver(&uhci_pci_driver);
        if (retval)
                goto init_failed;

        return 0;

init_failed:
        if (kmem_cache_destroy(uhci_up_cachep))
                warn("not all urb_priv's were freed!");

up_failed:
        debugfs_remove(uhci_debugfs_root);

debug_failed:
        if (errbuf)
                kfree(errbuf);

errbuf_failed:

        return retval;
}

static void __exit uhci_hcd_cleanup(void) 
{
        pci_unregister_driver(&uhci_pci_driver);
        
        if (kmem_cache_destroy(uhci_up_cachep))
                warn("not all urb_priv's were freed!");

        debugfs_remove(uhci_debugfs_root);

        if (errbuf)
                kfree(errbuf);
}

module_init(uhci_hcd_init);
module_exit(uhci_hcd_cleanup);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");