/*
 * Copyright (c) 2001-2002 by David Brownell
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* this file is part of ehci-hcd.c */

#define ehci_dbg(ehci, fmt, args...) \
        dev_dbg (ehci_to_hcd(ehci)->self.controller , fmt , ## args )
#define ehci_err(ehci, fmt, args...) \
        dev_err (ehci_to_hcd(ehci)->self.controller , fmt , ## args )
#define ehci_info(ehci, fmt, args...) \
        dev_info (ehci_to_hcd(ehci)->self.controller , fmt , ## args )
#define ehci_warn(ehci, fmt, args...) \
        dev_warn (ehci_to_hcd(ehci)->self.controller , fmt , ## args )

#ifdef VERBOSE_DEBUG
#       define ehci_vdbg ehci_dbg
#else
        static inline void ehci_vdbg(struct ehci_hcd *ehci, ...) {}
#endif

#ifdef  DEBUG

/* check the values in the HCSPARAMS register
 * (host controller _Structural_ parameters)
 * see EHCI spec, Table 2-4 for each value
 */
static void dbg_hcs_params (struct ehci_hcd *ehci, char *label)
{
        u32     params = ehci_readl(ehci, &ehci->caps->hcs_params);

        ehci_dbg (ehci,
                "%s hcs_params 0x%x dbg=%d%s cc=%d pcc=%d%s%s ports=%d\n",
                label, params,
                HCS_DEBUG_PORT (params),
                HCS_INDICATOR (params) ? " ind" : "",
                HCS_N_CC (params),
                HCS_N_PCC (params),
                HCS_PORTROUTED (params) ? "" : " ordered",
                HCS_PPC (params) ? "" : " !ppc",
                HCS_N_PORTS (params)
                );
        /* Port routing, per EHCI 0.95 Spec, Section 2.2.5 */
        if (HCS_PORTROUTED (params)) {
                int i;
                char buf [46], tmp [7], byte;

                buf[0] = 0;
                for (i = 0; i < HCS_N_PORTS (params); i++) {
                        // FIXME MIPS won't readb() ...
                        byte = readb (&ehci->caps->portroute[(i>>1)]);
                        sprintf(tmp, "%d ",
                                ((i & 0x1) ? ((byte)&0xf) : ((byte>>4)&0xf)));
                        strcat(buf, tmp);
                }
                ehci_dbg (ehci, "%s portroute %s\n",
                                label, buf);
        }
}
#else

static inline void dbg_hcs_params (struct ehci_hcd *ehci, char *label) {}

#endif

#ifdef  DEBUG

/* check the values in the HCCPARAMS register
 * (host controller _Capability_ parameters)
 * see EHCI Spec, Table 2-5 for each value
 * */
static void dbg_hcc_params (struct ehci_hcd *ehci, char *label)
{
        u32     params = ehci_readl(ehci, &ehci->caps->hcc_params);

        if (HCC_ISOC_CACHE (params)) {
                ehci_dbg (ehci,
                        "%s hcc_params %04x caching frame %s%s%s\n",
                        label, params,
                        HCC_PGM_FRAMELISTLEN(params) ? "256/512/1024" : "1024",
                        HCC_CANPARK(params) ? " park" : "",
                        HCC_64BIT_ADDR(params) ? " 64 bit addr" : "");
        } else {
                ehci_dbg (ehci,
                        "%s hcc_params %04x thresh %d uframes %s%s%s%s%s%s%s\n",
                        label,
                        params,
                        HCC_ISOC_THRES(params),
                        HCC_PGM_FRAMELISTLEN(params) ? "256/512/1024" : "1024",
                        HCC_CANPARK(params) ? " park" : "",
                        HCC_64BIT_ADDR(params) ? " 64 bit addr" : "",
                        HCC_LPM(params) ? " LPM" : "",
                        HCC_PER_PORT_CHANGE_EVENT(params) ? " ppce" : "",
                        HCC_HW_PREFETCH(params) ? " hw prefetch" : "",
                        HCC_32FRAME_PERIODIC_LIST(params) ?
                                " 32 peridic list" : "");
        }
}
#else

static inline void dbg_hcc_params (struct ehci_hcd *ehci, char *label) {}

#endif

#ifdef  DEBUG

static void __maybe_unused
dbg_qtd (const char *label, struct ehci_hcd *ehci, struct ehci_qtd *qtd)
{
        ehci_dbg(ehci, "%s td %p n%08x %08x t%08x p0=%08x\n", label, qtd,
                hc32_to_cpup(ehci, &qtd->hw_next),
                hc32_to_cpup(ehci, &qtd->hw_alt_next),
                hc32_to_cpup(ehci, &qtd->hw_token),
                hc32_to_cpup(ehci, &qtd->hw_buf [0]));
        if (qtd->hw_buf [1])
                ehci_dbg(ehci, "  p1=%08x p2=%08x p3=%08x p4=%08x\n",
                        hc32_to_cpup(ehci, &qtd->hw_buf[1]),
                        hc32_to_cpup(ehci, &qtd->hw_buf[2]),
                        hc32_to_cpup(ehci, &qtd->hw_buf[3]),
                        hc32_to_cpup(ehci, &qtd->hw_buf[4]));
}

static void __maybe_unused
dbg_qh (const char *label, struct ehci_hcd *ehci, struct ehci_qh *qh)
{
        struct ehci_qh_hw *hw = qh->hw;

        ehci_dbg (ehci, "%s qh %p n%08x info %x %x qtd %x\n", label,
                qh, hw->hw_next, hw->hw_info1, hw->hw_info2, hw->hw_current);
        dbg_qtd("overlay", ehci, (struct ehci_qtd *) &hw->hw_qtd_next);
}

static void __maybe_unused
dbg_itd (const char *label, struct ehci_hcd *ehci, struct ehci_itd *itd)
{
        ehci_dbg (ehci, "%s [%d] itd %p, next %08x, urb %p\n",
                label, itd->frame, itd, hc32_to_cpu(ehci, itd->hw_next),
                itd->urb);
        ehci_dbg (ehci,
                "  trans: %08x %08x %08x %08x %08x %08x %08x %08x\n",
                hc32_to_cpu(ehci, itd->hw_transaction[0]),
                hc32_to_cpu(ehci, itd->hw_transaction[1]),
                hc32_to_cpu(ehci, itd->hw_transaction[2]),
                hc32_to_cpu(ehci, itd->hw_transaction[3]),
                hc32_to_cpu(ehci, itd->hw_transaction[4]),
                hc32_to_cpu(ehci, itd->hw_transaction[5]),
                hc32_to_cpu(ehci, itd->hw_transaction[6]),
                hc32_to_cpu(ehci, itd->hw_transaction[7]));
        ehci_dbg (ehci,
                "  buf:   %08x %08x %08x %08x %08x %08x %08x\n",
                hc32_to_cpu(ehci, itd->hw_bufp[0]),
                hc32_to_cpu(ehci, itd->hw_bufp[1]),
                hc32_to_cpu(ehci, itd->hw_bufp[2]),
                hc32_to_cpu(ehci, itd->hw_bufp[3]),
                hc32_to_cpu(ehci, itd->hw_bufp[4]),
                hc32_to_cpu(ehci, itd->hw_bufp[5]),
                hc32_to_cpu(ehci, itd->hw_bufp[6]));
        ehci_dbg (ehci, "  index: %d %d %d %d %d %d %d %d\n",
                itd->index[0], itd->index[1], itd->index[2],
                itd->index[3], itd->index[4], itd->index[5],
                itd->index[6], itd->index[7]);
}

static void __maybe_unused
dbg_sitd (const char *label, struct ehci_hcd *ehci, struct ehci_sitd *sitd)
{
        ehci_dbg (ehci, "%s [%d] sitd %p, next %08x, urb %p\n",
                label, sitd->frame, sitd, hc32_to_cpu(ehci, sitd->hw_next),
                sitd->urb);
        ehci_dbg (ehci,
                "  addr %08x sched %04x result %08x buf %08x %08x\n",
                hc32_to_cpu(ehci, sitd->hw_fullspeed_ep),
                hc32_to_cpu(ehci, sitd->hw_uframe),
                hc32_to_cpu(ehci, sitd->hw_results),
                hc32_to_cpu(ehci, sitd->hw_buf[0]),
                hc32_to_cpu(ehci, sitd->hw_buf[1]));
}

static int __maybe_unused
dbg_status_buf (char *buf, unsigned len, const char *label, u32 status)
{
        return scnprintf (buf, len,
                "%s%sstatus %04x%s%s%s%s%s%s%s%s%s%s%s",
                label, label [0] ? " " : "", status,
                (status & STS_PPCE_MASK) ? " PPCE" : "",
                (status & STS_ASS) ? " Async" : "",
                (status & STS_PSS) ? " Periodic" : "",
                (status & STS_RECL) ? " Recl" : "",
                (status & STS_HALT) ? " Halt" : "",
                (status & STS_IAA) ? " IAA" : "",
                (status & STS_FATAL) ? " FATAL" : "",
                (status & STS_FLR) ? " FLR" : "",
                (status & STS_PCD) ? " PCD" : "",
                (status & STS_ERR) ? " ERR" : "",
                (status & STS_INT) ? " INT" : ""
                );
}

static int __maybe_unused
dbg_intr_buf (char *buf, unsigned len, const char *label, u32 enable)
{
        return scnprintf (buf, len,
                "%s%sintrenable %02x%s%s%s%s%s%s%s",
                label, label [0] ? " " : "", enable,
                (enable & STS_PPCE_MASK) ? " PPCE" : "",
                (enable & STS_IAA) ? " IAA" : "",
                (enable & STS_FATAL) ? " FATAL" : "",
                (enable & STS_FLR) ? " FLR" : "",
                (enable & STS_PCD) ? " PCD" : "",
                (enable & STS_ERR) ? " ERR" : "",
                (enable & STS_INT) ? " INT" : ""
                );
}

static const char *const fls_strings [] =
    { "1024", "512", "256", "??" };

static int
dbg_command_buf (char *buf, unsigned len, const char *label, u32 command)
{
        return scnprintf (buf, len,
                "%s%scommand %07x %s%s%s%s%s%s=%d ithresh=%d%s%s%s%s "
                "period=%s%s %s",
                label, label [0] ? " " : "", command,
                (command & CMD_HIRD) ? " HIRD" : "",
                (command & CMD_PPCEE) ? " PPCEE" : "",
                (command & CMD_FSP) ? " FSP" : "",
                (command & CMD_ASPE) ? " ASPE" : "",
                (command & CMD_PSPE) ? " PSPE" : "",
                (command & CMD_PARK) ? " park" : "(park)",
                CMD_PARK_CNT (command),
                (command >> 16) & 0x3f,
                (command & CMD_LRESET) ? " LReset" : "",
                (command & CMD_IAAD) ? " IAAD" : "",
                (command & CMD_ASE) ? " Async" : "",
                (command & CMD_PSE) ? " Periodic" : "",
                fls_strings [(command >> 2) & 0x3],
                (command & CMD_RESET) ? " Reset" : "",
                (command & CMD_RUN) ? "RUN" : "HALT"
                );
}

static int
dbg_port_buf (char *buf, unsigned len, const char *label, int port, u32 status)
{
        char    *sig;

        /* signaling state */
        switch (status & (3 << 10)) {
        case 0 << 10: sig = "se0"; break;
        case 1 << 10: sig = "k"; break;         /* low speed */
        case 2 << 10: sig = "j"; break;
        default: sig = "?"; break;
        }

        return scnprintf (buf, len,
                "%s%sport:%d status %06x %d %s%s%s%s%s%s "
                "sig=%s%s%s%s%s%s%s%s%s%s%s",
                label, label [0] ? " " : "", port, status,
                status>>25,/*device address */
                (status & PORT_SSTS)>>23 == PORTSC_SUSPEND_STS_ACK ?
                                                " ACK" : "",
                (status & PORT_SSTS)>>23 == PORTSC_SUSPEND_STS_NYET ?
                                                " NYET" : "",
                (status & PORT_SSTS)>>23 == PORTSC_SUSPEND_STS_STALL ?
                                                " STALL" : "",
                (status & PORT_SSTS)>>23 == PORTSC_SUSPEND_STS_ERR ?
                                                " ERR" : "",
                (status & PORT_POWER) ? " POWER" : "",
                (status & PORT_OWNER) ? " OWNER" : "",
                sig,
                (status & PORT_LPM) ? " LPM" : "",
                (status & PORT_RESET) ? " RESET" : "",
                (status & PORT_SUSPEND) ? " SUSPEND" : "",
                (status & PORT_RESUME) ? " RESUME" : "",
                (status & PORT_OCC) ? " OCC" : "",
                (status & PORT_OC) ? " OC" : "",
                (status & PORT_PEC) ? " PEC" : "",
                (status & PORT_PE) ? " PE" : "",
                (status & PORT_CSC) ? " CSC" : "",
                (status & PORT_CONNECT) ? " CONNECT" : "");
}

#else
static inline void __maybe_unused
dbg_qh (char *label, struct ehci_hcd *ehci, struct ehci_qh *qh)
{}

static inline int __maybe_unused
dbg_status_buf (char *buf, unsigned len, const char *label, u32 status)
{ return 0; }

static inline int __maybe_unused
dbg_command_buf (char *buf, unsigned len, const char *label, u32 command)
{ return 0; }

static inline int __maybe_unused
dbg_intr_buf (char *buf, unsigned len, const char *label, u32 enable)
{ return 0; }

static inline int __maybe_unused
dbg_port_buf (char *buf, unsigned len, const char *label, int port, u32 status)
{ return 0; }

#endif  /* DEBUG */

/* functions have the "wrong" filename when they're output... */
#define dbg_status(ehci, label, status) { \
        char _buf [80]; \
        dbg_status_buf (_buf, sizeof _buf, label, status); \
        ehci_dbg (ehci, "%s\n", _buf); \
}

#define dbg_cmd(ehci, label, command) { \
        char _buf [80]; \
        dbg_command_buf (_buf, sizeof _buf, label, command); \
        ehci_dbg (ehci, "%s\n", _buf); \
}

#define dbg_port(ehci, label, port, status) { \
        char _buf [80]; \
        dbg_port_buf (_buf, sizeof _buf, label, port, status); \
        ehci_dbg (ehci, "%s\n", _buf); \
}

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

#ifdef STUB_DEBUG_FILES

static inline void create_debug_files (struct ehci_hcd *bus) { }
static inline void remove_debug_files (struct ehci_hcd *bus) { }

#else

/* troubleshooting help: expose state in debugfs */

static int debug_async_open(struct inode *, struct file *);
static int debug_periodic_open(struct inode *, struct file *);
static int debug_registers_open(struct inode *, struct file *);
static int debug_async_open(struct inode *, struct file *);
static int debug_lpm_open(struct inode *, struct file *);
static ssize_t debug_lpm_read(struct file *file, char __user *user_buf,
                                   size_t count, loff_t *ppos);
static ssize_t debug_lpm_write(struct file *file, const char __user *buffer,
                              size_t count, loff_t *ppos);
static int debug_lpm_close(struct inode *inode, struct file *file);

static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
static int debug_close(struct inode *, struct file *);

static const struct file_operations debug_async_fops = {
        .owner          = THIS_MODULE,
        .open           = debug_async_open,
        .read           = debug_output,
        .release        = debug_close,
        .llseek         = default_llseek,
};
static const struct file_operations debug_periodic_fops = {
        .owner          = THIS_MODULE,
        .open           = debug_periodic_open,
        .read           = debug_output,
        .release        = debug_close,
        .llseek         = default_llseek,
};
static const struct file_operations debug_registers_fops = {
        .owner          = THIS_MODULE,
        .open           = debug_registers_open,
        .read           = debug_output,
        .release        = debug_close,
        .llseek         = default_llseek,
};
static const struct file_operations debug_lpm_fops = {
        .owner          = THIS_MODULE,
        .open           = debug_lpm_open,
        .read           = debug_lpm_read,
        .write          = debug_lpm_write,
        .release        = debug_lpm_close,
        .llseek         = noop_llseek,
};

static struct dentry *ehci_debug_root;

struct debug_buffer {
        ssize_t (*fill_func)(struct debug_buffer *);    /* fill method */
        struct usb_bus *bus;
        struct mutex mutex;     /* protect filling of buffer */
        size_t count;           /* number of characters filled into buffer */
        char *output_buf;
        size_t alloc_size;
};

#define speed_char(info1) ({ char tmp; \
                switch (info1 & (3 << 12)) { \
                case 0 << 12: tmp = 'f'; break; \
                case 1 << 12: tmp = 'l'; break; \
                case 2 << 12: tmp = 'h'; break; \
                default: tmp = '?'; break; \
                }; tmp; })

static inline char token_mark(struct ehci_hcd *ehci, __hc32 token)
{
        __u32 v = hc32_to_cpu(ehci, token);

        if (v & QTD_STS_ACTIVE)
                return '*';
        if (v & QTD_STS_HALT)
                return '-';
        if (!IS_SHORT_READ (v))
                return ' ';
        /* tries to advance through hw_alt_next */
        return '/';
}

static void qh_lines (
        struct ehci_hcd *ehci,
        struct ehci_qh *qh,
        char **nextp,
        unsigned *sizep
)
{
        u32                     scratch;
        u32                     hw_curr;
        struct list_head        *entry;
        struct ehci_qtd         *td;
        unsigned                temp;
        unsigned                size = *sizep;
        char                    *next = *nextp;
        char                    mark;
        __le32                  list_end = EHCI_LIST_END(ehci);
        struct ehci_qh_hw       *hw = qh->hw;

        if (hw->hw_qtd_next == list_end)        /* NEC does this */
                mark = '@';
        else
                mark = token_mark(ehci, hw->hw_token);
        if (mark == '/') {      /* qh_alt_next controls qh advance? */
                if ((hw->hw_alt_next & QTD_MASK(ehci))
                                == ehci->async->hw->hw_alt_next)
                        mark = '#';     /* blocked */
                else if (hw->hw_alt_next == list_end)
                        mark = '.';     /* use hw_qtd_next */
                /* else alt_next points to some other qtd */
        }
        scratch = hc32_to_cpup(ehci, &hw->hw_info1);
        hw_curr = (mark == '*') ? hc32_to_cpup(ehci, &hw->hw_current) : 0;
        temp = scnprintf (next, size,
                        "qh/%p dev%d %cs ep%d %08x %08x (%08x%c %s nak%d)",
                        qh, scratch & 0x007f,
                        speed_char (scratch),
                        (scratch >> 8) & 0x000f,
                        scratch, hc32_to_cpup(ehci, &hw->hw_info2),
                        hc32_to_cpup(ehci, &hw->hw_token), mark,
                        (cpu_to_hc32(ehci, QTD_TOGGLE) & hw->hw_token)
                                ? "data1" : "data0",
                        (hc32_to_cpup(ehci, &hw->hw_alt_next) >> 1) & 0x0f);
        size -= temp;
        next += temp;

        /* hc may be modifying the list as we read it ... */
        list_for_each (entry, &qh->qtd_list) {
                td = list_entry (entry, struct ehci_qtd, qtd_list);
                scratch = hc32_to_cpup(ehci, &td->hw_token);
                mark = ' ';
                if (hw_curr == td->qtd_dma)
                        mark = '*';
                else if (hw->hw_qtd_next == cpu_to_hc32(ehci, td->qtd_dma))
                        mark = '+';
                else if (QTD_LENGTH (scratch)) {
                        if (td->hw_alt_next == ehci->async->hw->hw_alt_next)
                                mark = '#';
                        else if (td->hw_alt_next != list_end)
                                mark = '/';
                }
                temp = snprintf (next, size,
                                "\n\t%p%c%s len=%d %08x urb %p",
                                td, mark, ({ char *tmp;
                                 switch ((scratch>>8)&0x03) {
                                 case 0: tmp = "out"; break;
                                 case 1: tmp = "in"; break;
                                 case 2: tmp = "setup"; break;
                                 default: tmp = "?"; break;
                                 } tmp;}),
                                (scratch >> 16) & 0x7fff,
                                scratch,
                                td->urb);
                if (size < temp)
                        temp = size;
                size -= temp;
                next += temp;
                if (temp == size)
                        goto done;
        }

        temp = snprintf (next, size, "\n");
        if (size < temp)
                temp = size;
        size -= temp;
        next += temp;

done:
        *sizep = size;
        *nextp = next;
}

static ssize_t fill_async_buffer(struct debug_buffer *buf)
{
        struct usb_hcd          *hcd;
        struct ehci_hcd         *ehci;
        unsigned long           flags;
        unsigned                temp, size;
        char                    *next;
        struct ehci_qh          *qh;

        hcd = bus_to_hcd(buf->bus);
        ehci = hcd_to_ehci (hcd);
        next = buf->output_buf;
        size = buf->alloc_size;

        *next = 0;

        /* dumps a snapshot of the async schedule.
         * usually empty except for long-term bulk reads, or head.
         * one QH per line, and TDs we know about
         */
        spin_lock_irqsave (&ehci->lock, flags);
        for (qh = ehci->async->qh_next.qh; size > 0 && qh; qh = qh->qh_next.qh)
                qh_lines (ehci, qh, &next, &size);
        if (ehci->reclaim && size > 0) {
                temp = scnprintf (next, size, "\nreclaim =\n");
                size -= temp;
                next += temp;

                for (qh = ehci->reclaim; size > 0 && qh; qh = qh->reclaim)
                        qh_lines (ehci, qh, &next, &size);
        }
        spin_unlock_irqrestore (&ehci->lock, flags);

        return strlen(buf->output_buf);
}

#define DBG_SCHED_LIMIT 64
static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
{
        struct usb_hcd          *hcd;
        struct ehci_hcd         *ehci;
        unsigned long           flags;
        union ehci_shadow       p, *seen;
        unsigned                temp, size, seen_count;
        char                    *next;
        unsigned                i;
        __hc32                  tag;

        if (!(seen = kmalloc (DBG_SCHED_LIMIT * sizeof *seen, GFP_ATOMIC)))
                return 0;
        seen_count = 0;

        hcd = bus_to_hcd(buf->bus);
        ehci = hcd_to_ehci (hcd);
        next = buf->output_buf;
        size = buf->alloc_size;

        temp = scnprintf (next, size, "size = %d\n", ehci->periodic_size);
        size -= temp;
        next += temp;

        /* dump a snapshot of the periodic schedule.
         * iso changes, interrupt usually doesn't.
         */
        spin_lock_irqsave (&ehci->lock, flags);
        for (i = 0; i < ehci->periodic_size; i++) {
                p = ehci->pshadow [i];
                if (likely (!p.ptr))
                        continue;
                tag = Q_NEXT_TYPE(ehci, ehci->periodic [i]);

                temp = scnprintf (next, size, "%4d: ", i);
                size -= temp;
                next += temp;

                do {
                        struct ehci_qh_hw *hw;

                        switch (hc32_to_cpu(ehci, tag)) {
                        case Q_TYPE_QH:
                                hw = p.qh->hw;
                                temp = scnprintf (next, size, " qh%d-%04x/%p",
                                                p.qh->period,
                                                hc32_to_cpup(ehci,
                                                        &hw->hw_info2)
                                                        /* uframe masks */
                                                        & (QH_CMASK | QH_SMASK),
                                                p.qh);
                                size -= temp;
                                next += temp;
                                /* don't repeat what follows this qh */
                                for (temp = 0; temp < seen_count; temp++) {
                                        if (seen [temp].ptr != p.ptr)
                                                continue;
                                        if (p.qh->qh_next.ptr) {
                                                temp = scnprintf (next, size,
                                                        " ...");
                                                size -= temp;
                                                next += temp;
                                        }
                                        break;
                                }
                                /* show more info the first time around */
                                if (temp == seen_count) {
                                        u32     scratch = hc32_to_cpup(ehci,
                                                        &hw->hw_info1);
                                        struct ehci_qtd *qtd;
                                        char            *type = "";

                                        /* count tds, get ep direction */
                                        temp = 0;
                                        list_for_each_entry (qtd,
                                                        &p.qh->qtd_list,
                                                        qtd_list) {
                                                temp++;
                                                switch (0x03 & (hc32_to_cpu(
                                                        ehci,
                                                        qtd->hw_token) >> 8)) {
                                                case 0: type = "out"; continue;
                                                case 1: type = "in"; continue;
                                                }
                                        }

                                        temp = scnprintf (next, size,
                                                " (%c%d ep%d%s "
                                                "[%d/%d] q%d p%d)",
                                                speed_char (scratch),
                                                scratch & 0x007f,
                                                (scratch >> 8) & 0x000f, type,
                                                p.qh->usecs, p.qh->c_usecs,
                                                temp,
                                                0x7ff & (scratch >> 16));

                                        if (seen_count < DBG_SCHED_LIMIT)
                                                seen [seen_count++].qh = p.qh;
                                } else
                                        temp = 0;
                                if (p.qh) {
                                        tag = Q_NEXT_TYPE(ehci, hw->hw_next);
                                        p = p.qh->qh_next;
                                }
                                break;
                        case Q_TYPE_FSTN:
                                temp = scnprintf (next, size,
                                        " fstn-%8x/%p", p.fstn->hw_prev,
                                        p.fstn);
                                tag = Q_NEXT_TYPE(ehci, p.fstn->hw_next);
                                p = p.fstn->fstn_next;
                                break;
                        case Q_TYPE_ITD:
                                temp = scnprintf (next, size,
                                        " itd/%p", p.itd);
                                tag = Q_NEXT_TYPE(ehci, p.itd->hw_next);
                                p = p.itd->itd_next;
                                break;
                        case Q_TYPE_SITD:
                                temp = scnprintf (next, size,
                                        " sitd%d-%04x/%p",
                                        p.sitd->stream->interval,
                                        hc32_to_cpup(ehci, &p.sitd->hw_uframe)
                                                & 0x0000ffff,
                                        p.sitd);
                                tag = Q_NEXT_TYPE(ehci, p.sitd->hw_next);
                                p = p.sitd->sitd_next;
                                break;
                        }
                        size -= temp;
                        next += temp;
                } while (p.ptr);

                temp = scnprintf (next, size, "\n");
                size -= temp;
                next += temp;
        }
        spin_unlock_irqrestore (&ehci->lock, flags);
        kfree (seen);

        return buf->alloc_size - size;
}
#undef DBG_SCHED_LIMIT

static ssize_t fill_registers_buffer(struct debug_buffer *buf)
{
        struct usb_hcd          *hcd;
        struct ehci_hcd         *ehci;
        unsigned long           flags;
        unsigned                temp, size, i;
        char                    *next, scratch [80];
        static char             fmt [] = "%*s\n";
        static char             label [] = "";

        hcd = bus_to_hcd(buf->bus);
        ehci = hcd_to_ehci (hcd);
        next = buf->output_buf;
        size = buf->alloc_size;

        spin_lock_irqsave (&ehci->lock, flags);

        if (!HCD_HW_ACCESSIBLE(hcd)) {
                size = scnprintf (next, size,
                        "bus %s, device %s\n"
                        "%s\n"
                        "SUSPENDED (no register access)\n",
                        hcd->self.controller->bus->name,
                        dev_name(hcd->self.controller),
                        hcd->product_desc);
                goto done;
        }

        /* Capability Registers */
        i = HC_VERSION(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
        temp = scnprintf (next, size,
                "bus %s, device %s\n"
                "%s\n"
                "EHCI %x.%02x, hcd state %d\n",
                hcd->self.controller->bus->name,
                dev_name(hcd->self.controller),
                hcd->product_desc,
                i >> 8, i & 0x0ff, hcd->state);
        size -= temp;
        next += temp;

#ifdef  CONFIG_PCI
        /* EHCI 0.96 and later may have "extended capabilities" */
        if (hcd->self.controller->bus == &pci_bus_type) {
                struct pci_dev  *pdev;
                u32             offset, cap, cap2;
                unsigned        count = 256/4;

                pdev = to_pci_dev(ehci_to_hcd(ehci)->self.controller);
                offset = HCC_EXT_CAPS(ehci_readl(ehci,
                                &ehci->caps->hcc_params));
                while (offset && count--) {
                        pci_read_config_dword (pdev, offset, &cap);
                        switch (cap & 0xff) {
                        case 1:
                                temp = scnprintf (next, size,
                                        "ownership %08x%s%s\n", cap,
                                        (cap & (1 << 24)) ? " linux" : "",
                                        (cap & (1 << 16)) ? " firmware" : "");
                                size -= temp;
                                next += temp;

                                offset += 4;
                                pci_read_config_dword (pdev, offset, &cap2);
                                temp = scnprintf (next, size,
                                        "SMI sts/enable 0x%08x\n", cap2);
                                size -= temp;
                                next += temp;
                                break;
                        case 0:         /* illegal reserved capability */
                                cap = 0;
                                /* FALLTHROUGH */
                        default:                /* unknown */
                                break;
                        }
                        temp = (cap >> 8) & 0xff;
                }
        }
#endif

        // FIXME interpret both types of params
        i = ehci_readl(ehci, &ehci->caps->hcs_params);
        temp = scnprintf (next, size, "structural params 0x%08x\n", i);
        size -= temp;
        next += temp;

        i = ehci_readl(ehci, &ehci->caps->hcc_params);
        temp = scnprintf (next, size, "capability params 0x%08x\n", i);
        size -= temp;
        next += temp;

        /* Operational Registers */
        temp = dbg_status_buf (scratch, sizeof scratch, label,
                        ehci_readl(ehci, &ehci->regs->status));
        temp = scnprintf (next, size, fmt, temp, scratch);
        size -= temp;
        next += temp;

        temp = dbg_command_buf (scratch, sizeof scratch, label,
                        ehci_readl(ehci, &ehci->regs->command));
        temp = scnprintf (next, size, fmt, temp, scratch);
        size -= temp;
        next += temp;

        temp = dbg_intr_buf (scratch, sizeof scratch, label,
                        ehci_readl(ehci, &ehci->regs->intr_enable));
        temp = scnprintf (next, size, fmt, temp, scratch);
        size -= temp;
        next += temp;

        temp = scnprintf (next, size, "uframe %04x\n",
                        ehci_readl(ehci, &ehci->regs->frame_index));
        size -= temp;
        next += temp;

        for (i = 1; i <= HCS_N_PORTS (ehci->hcs_params); i++) {
                temp = dbg_port_buf (scratch, sizeof scratch, label, i,
                                ehci_readl(ehci,
                                        &ehci->regs->port_status[i - 1]));
                temp = scnprintf (next, size, fmt, temp, scratch);
                size -= temp;
                next += temp;
                if (i == HCS_DEBUG_PORT(ehci->hcs_params) && ehci->debug) {
                        temp = scnprintf (next, size,
                                        "    debug control %08x\n",
                                        ehci_readl(ehci,
                                                &ehci->debug->control));
                        size -= temp;
                        next += temp;
                }
        }

        if (ehci->reclaim) {
                temp = scnprintf(next, size, "reclaim qh %p\n", ehci->reclaim);
                size -= temp;
                next += temp;
        }

#ifdef EHCI_STATS
        temp = scnprintf (next, size,
                "irq normal %ld err %ld reclaim %ld (lost %ld)\n",
                ehci->stats.normal, ehci->stats.error, ehci->stats.reclaim,
                ehci->stats.lost_iaa);
        size -= temp;
        next += temp;

        temp = scnprintf (next, size, "complete %ld unlink %ld\n",
                ehci->stats.complete, ehci->stats.unlink);
        size -= temp;
        next += temp;
#endif

done:
        spin_unlock_irqrestore (&ehci->lock, flags);

        return buf->alloc_size - size;
}

static struct debug_buffer *alloc_buffer(struct usb_bus *bus,
                                ssize_t (*fill_func)(struct debug_buffer *))
{
        struct debug_buffer *buf;

        buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);

        if (buf) {
                buf->bus = bus;
                buf->fill_func = fill_func;
                mutex_init(&buf->mutex);
                buf->alloc_size = PAGE_SIZE;
        }

        return buf;
}

static int fill_buffer(struct debug_buffer *buf)
{
        int ret = 0;

        if (!buf->output_buf)
                buf->output_buf = vmalloc(buf->alloc_size);

        if (!buf->output_buf) {
                ret = -ENOMEM;
                goto out;
        }

        ret = buf->fill_func(buf);

        if (ret >= 0) {
                buf->count = ret;
                ret = 0;
        }

out:
        return ret;
}

static ssize_t debug_output(struct file *file, char __user *user_buf,
                            size_t len, loff_t *offset)
{
        struct debug_buffer *buf = file->private_data;
        int ret = 0;

        mutex_lock(&buf->mutex);
        if (buf->count == 0) {
                ret = fill_buffer(buf);
                if (ret != 0) {
                        mutex_unlock(&buf->mutex);
                        goto out;
                }
        }
        mutex_unlock(&buf->mutex);

        ret = simple_read_from_buffer(user_buf, len, offset,
                                      buf->output_buf, buf->count);

out:
        return ret;

}

static int debug_close(struct inode *inode, struct file *file)
{
        struct debug_buffer *buf = file->private_data;

        if (buf) {
                vfree(buf->output_buf);
                kfree(buf);
        }

        return 0;
}
static int debug_async_open(struct inode *inode, struct file *file)
{
        file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);

        return file->private_data ? 0 : -ENOMEM;
}

static int debug_periodic_open(struct inode *inode, struct file *file)
{
        struct debug_buffer *buf;
        buf = alloc_buffer(inode->i_private, fill_periodic_buffer);
        if (!buf)
                return -ENOMEM;

        buf->alloc_size = (sizeof(void *) == 4 ? 6 : 8)*PAGE_SIZE;
        file->private_data = buf;
        return 0;
}

static int debug_registers_open(struct inode *inode, struct file *file)
{
        file->private_data = alloc_buffer(inode->i_private,
                                          fill_registers_buffer);

        return file->private_data ? 0 : -ENOMEM;
}

static int debug_lpm_open(struct inode *inode, struct file *file)
{
        file->private_data = inode->i_private;
        return 0;
}

static int debug_lpm_close(struct inode *inode, struct file *file)
{
        return 0;
}

static ssize_t debug_lpm_read(struct file *file, char __user *user_buf,
                                   size_t count, loff_t *ppos)
{
        /* TODO: show lpm stats */
        return 0;
}

static ssize_t debug_lpm_write(struct file *file, const char __user *user_buf,
                              size_t count, loff_t *ppos)
{
        struct usb_hcd          *hcd;
        struct ehci_hcd         *ehci;
        char buf[50];
        size_t len;
        u32 temp;
        unsigned long port;
        u32 __iomem     *portsc ;
        u32 params;

        hcd = bus_to_hcd(file->private_data);
        ehci = hcd_to_ehci(hcd);

        len = min(count, sizeof(buf) - 1);
        if (copy_from_user(buf, user_buf, len))
                return -EFAULT;
        buf[len] = '\0';
        if (len > 0 && buf[len - 1] == '\n')
                buf[len - 1] = '\0';

        if (strncmp(buf, "enable", 5) == 0) {

                if (strict_strtoul(buf + 7, 10, &port))
                        return -EINVAL;
                params = ehci_readl(ehci, &ehci->caps->hcs_params);
                if (port > HCS_N_PORTS(params)) {
                        ehci_dbg(ehci, "ERR: LPM on bad port %lu\n", port);
                        return -ENODEV;
                }
                portsc = &ehci->regs->port_status[port-1];
                temp = ehci_readl(ehci, portsc);
                if (!(temp & PORT_DEV_ADDR)) {
                        ehci_dbg(ehci, "LPM: no device attached\n");
                        return -ENODEV;
                }
                temp |= PORT_LPM;
                ehci_writel(ehci, temp, portsc);
                printk(KERN_INFO "force enable LPM for port %lu\n", port);
        } else if (strncmp(buf, "hird=", 5) == 0) {
                unsigned long hird;
                if (strict_strtoul(buf + 5, 16, &hird))
                        return -EINVAL;
                printk(KERN_INFO "setting hird %s %lu\n", buf + 6, hird);
                temp = ehci_readl(ehci, &ehci->regs->command);
                temp &= ~CMD_HIRD;
                temp |= hird << 24;
                ehci_writel(ehci, temp, &ehci->regs->command);
        } else if (strncmp(buf, "disable", 7) == 0) {
                if (strict_strtoul(buf + 8, 10, &port))
                        return -EINVAL;
                params = ehci_readl(ehci, &ehci->caps->hcs_params);
                if (port > HCS_N_PORTS(params)) {
                        ehci_dbg(ehci, "ERR: LPM off bad port %lu\n", port);
                        return -ENODEV;
                }
                portsc = &ehci->regs->port_status[port-1];
                temp = ehci_readl(ehci, portsc);
                if (!(temp & PORT_DEV_ADDR)) {
                        ehci_dbg(ehci, "ERR: no device attached\n");
                        return -ENODEV;
                }
                temp &= ~PORT_LPM;
                ehci_writel(ehci, temp, portsc);
                printk(KERN_INFO "disabled LPM for port %lu\n", port);
        } else
                return -EOPNOTSUPP;
        return count;
}

static inline void create_debug_files (struct ehci_hcd *ehci)
{
        struct usb_bus *bus = &ehci_to_hcd(ehci)->self;

        ehci->debug_dir = debugfs_create_dir(bus->bus_name, ehci_debug_root);
        if (!ehci->debug_dir)
                return;

        if (!debugfs_create_file("async", S_IRUGO, ehci->debug_dir, bus,
                                                &debug_async_fops))
                goto file_error;

        if (!debugfs_create_file("periodic", S_IRUGO, ehci->debug_dir, bus,
                                                &debug_periodic_fops))
                goto file_error;

        if (!debugfs_create_file("registers", S_IRUGO, ehci->debug_dir, bus,
                                                    &debug_registers_fops))
                goto file_error;

        if (!debugfs_create_file("lpm", S_IRUGO|S_IWUSR, ehci->debug_dir, bus,
                                                    &debug_lpm_fops))
                goto file_error;

        return;

file_error:
        debugfs_remove_recursive(ehci->debug_dir);
}

static inline void remove_debug_files (struct ehci_hcd *ehci)
{
        debugfs_remove_recursive(ehci->debug_dir);
}

#endif /* STUB_DEBUG_FILES */