irda-usb.c

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/*****************************************************************************
 *
 * Filename:      irda-usb.c
 * Version:       0.10
 * Description:   IrDA-USB Driver
 * Status:        Experimental 
 * Author:        Dag Brattli <[email protected]>
 *
 *  Copyright (C) 2000, Roman Weissgaerber <[email protected]>
 *      Copyright (C) 2001, Dag Brattli <[email protected]>
 *      Copyright (C) 2001, Jean Tourrilhes <[email protected]>
 *      Copyright (C) 2004, SigmaTel, Inc. <[email protected]>
 *      Copyright (C) 2005, Milan Beno <[email protected]>
 *      Copyright (C) 2006, Nick Fedchik <[email protected]>
 *          
 *  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.
 *
 *****************************************************************************/

/*
 *              IMPORTANT NOTE
 *              --------------
 *
 * As of kernel 2.5.20, this is the state of compliance and testing of
 * this driver (irda-usb) with regards to the USB low level drivers...
 *
 * This driver has been tested SUCCESSFULLY with the following drivers :
 *  o usb-uhci-hcd  (For Intel/Via USB controllers)
 *  o uhci-hcd  (Alternate/JE driver for Intel/Via USB controllers)
 *  o ohci-hcd  (For other USB controllers)
 *
 * This driver has NOT been tested with the following drivers :
 *  o ehci-hcd  (USB 2.0 controllers)
 *
 * Note that all HCD drivers do URB_ZERO_PACKET and timeout properly,
 * so we don't have to worry about that anymore.
 * One common problem is the failure to set the address on the dongle,
 * but this happens before the driver gets loaded...
 *
 * Jean II
 */

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

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <linux/rtnetlink.h>
#include <linux/usb.h>
#include <linux/firmware.h>

#include "irda-usb.h"

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

static int qos_mtt_bits = 0;

/* These are the currently known IrDA USB dongles. Add new dongles here */
static struct usb_device_id dongles[] = {
    /* ACTiSYS Corp.,  ACT-IR2000U FIR-USB Adapter */
    { USB_DEVICE(0x9c4, 0x011), .driver_info = IUC_SPEED_BUG | IUC_NO_WINDOW },
    /* Look like ACTiSYS, Report : IBM Corp., IBM UltraPort IrDA */
    { USB_DEVICE(0x4428, 0x012), .driver_info = IUC_SPEED_BUG | IUC_NO_WINDOW },
    /* KC Technology Inc.,  KC-180 USB IrDA Device */
    { USB_DEVICE(0x50f, 0x180), .driver_info = IUC_SPEED_BUG | IUC_NO_WINDOW },
    /* Extended Systems, Inc.,  XTNDAccess IrDA USB (ESI-9685) */
    { USB_DEVICE(0x8e9, 0x100), .driver_info = IUC_SPEED_BUG | IUC_NO_WINDOW },
    /* SigmaTel STIR4210/4220/4116 USB IrDA (VFIR) Bridge */
    { USB_DEVICE(0x66f, 0x4210), .driver_info = IUC_STIR421X | IUC_SPEED_BUG },
    { USB_DEVICE(0x66f, 0x4220), .driver_info = IUC_STIR421X | IUC_SPEED_BUG },
    { USB_DEVICE(0x66f, 0x4116), .driver_info = IUC_STIR421X | IUC_SPEED_BUG },
    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |
      USB_DEVICE_ID_MATCH_INT_SUBCLASS,
      .bInterfaceClass = USB_CLASS_APP_SPEC,
      .bInterfaceSubClass = USB_CLASS_IRDA,
      .driver_info = IUC_DEFAULT, },
    { }, /* The end */
};

/*
 * Important note :
 * Devices based on the SigmaTel chipset (0x66f, 0x4200) are not designed
 * using the "USB-IrDA specification" (yes, there exist such a thing), and
 * therefore not supported by this driver (don't add them above).
 * There is a Linux driver, stir4200, that support those USB devices.
 * Jean II
 */

MODULE_DEVICE_TABLE(usb, dongles);

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

static void irda_usb_init_qos(struct irda_usb_cb *self) ;
static struct irda_class_desc *irda_usb_find_class_desc(struct usb_interface *intf);
static void irda_usb_disconnect(struct usb_interface *intf);
static void irda_usb_change_speed_xbofs(struct irda_usb_cb *self);
static netdev_tx_t irda_usb_hard_xmit(struct sk_buff *skb,
                        struct net_device *dev);
static int irda_usb_open(struct irda_usb_cb *self);
static void irda_usb_close(struct irda_usb_cb *self);
static void speed_bulk_callback(struct urb *urb);
static void write_bulk_callback(struct urb *urb);
static void irda_usb_receive(struct urb *urb);
static void irda_usb_rx_defer_expired(unsigned long data);
static int irda_usb_net_open(struct net_device *dev);
static int irda_usb_net_close(struct net_device *dev);
static int irda_usb_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
static void irda_usb_net_timeout(struct net_device *dev);

/************************ TRANSMIT ROUTINES ************************/
/*
 * Receive packets from the IrDA stack and send them on the USB pipe.
 * Handle speed change, timeout and lot's of ugliness...
 */

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_build_header(self, skb, header)
 *
 *   Builds USB-IrDA outbound header
 *
 * When we send an IrDA frame over an USB pipe, we add to it a 1 byte
 * header. This function create this header with the proper values.
 *
 * Important note : the USB-IrDA spec 1.0 say very clearly in chapter 5.4.2.2
 * that the setting of the link speed and xbof number in this outbound header
 * should be applied *AFTER* the frame has been sent.
 * Unfortunately, some devices are not compliant with that... It seems that
 * reading the spec is far too difficult...
 * Jean II
 */
static void irda_usb_build_header(struct irda_usb_cb *self,
                  __u8 *header,
                  int   force)
{
    /* Here we check if we have an STIR421x chip,
     * and if either speed or xbofs (or both) needs
     * to be changed.
     */
    if (self->capability & IUC_STIR421X &&
        ((self->new_speed != -1) || (self->new_xbofs != -1))) {

        /* With STIR421x, speed and xBOFs must be set at the same
         * time, even if only one of them changes.
         */
        if (self->new_speed == -1)
            self->new_speed = self->speed ;

        if (self->new_xbofs == -1)
            self->new_xbofs = self->xbofs ;
    }

    /* Set the link speed */
    if (self->new_speed != -1) {
        /* Hum... Ugly hack :-(
         * Some device are not compliant with the spec and change
         * parameters *before* sending the frame. - Jean II
         */
        if ((self->capability & IUC_SPEED_BUG) &&
            (!force) && (self->speed != -1)) {
            /* No speed and xbofs change here
             * (we'll do it later in the write callback) */
            IRDA_DEBUG(2, "%s(), not changing speed yet\n", __func__);
            *header = 0;
            return;
        }

        IRDA_DEBUG(2, "%s(), changing speed to %d\n", __func__, self->new_speed);
        self->speed = self->new_speed;
        /* We will do ` self->new_speed = -1; ' in the completion
         * handler just in case the current URB fail - Jean II */

        switch (self->speed) {
        case 2400:
                *header = SPEED_2400;
            break;
        default:
        case 9600:
            *header = SPEED_9600;
            break;
        case 19200:
            *header = SPEED_19200;
            break;
        case 38400:
            *header = SPEED_38400;
            break;
        case 57600:
                *header = SPEED_57600;
            break;
        case 115200:
                *header = SPEED_115200;
            break;
        case 576000:
                *header = SPEED_576000;
            break;
        case 1152000:
                *header = SPEED_1152000;
            break;
        case 4000000:
                *header = SPEED_4000000;
            self->new_xbofs = 0;
            break;
        case 16000000:
            *header = SPEED_16000000;
            self->new_xbofs = 0;
            break;
        }
    } else
        /* No change */
        *header = 0;
    
    /* Set the negotiated additional XBOFS */
    if (self->new_xbofs != -1) {
        IRDA_DEBUG(2, "%s(), changing xbofs to %d\n", __func__, self->new_xbofs);
        self->xbofs = self->new_xbofs;
        /* We will do ` self->new_xbofs = -1; ' in the completion
         * handler just in case the current URB fail - Jean II */

        switch (self->xbofs) {
        case 48:
            *header |= 0x10;
            break;
        case 28:
        case 24:    /* USB spec 1.0 says 24 */
            *header |= 0x20;
            break;
        default:
        case 12:
            *header |= 0x30;
            break;
        case 5: /* Bug in IrLAP spec? (should be 6) */
        case 6:
            *header |= 0x40;
            break;
        case 3:
            *header |= 0x50;
            break;
        case 2:
            *header |= 0x60;
            break;
        case 1:
            *header |= 0x70;
            break;
        case 0:
            *header |= 0x80;
            break;
        }
    }
}

/*
*   calculate turnaround time for SigmaTel header
*/
static __u8 get_turnaround_time(struct sk_buff *skb)
{
    int turnaround_time = irda_get_mtt(skb);

    if ( turnaround_time == 0 )
        return 0;
    else if ( turnaround_time <= 10 )
        return 1;
    else if ( turnaround_time <= 50 )
        return 2;
    else if ( turnaround_time <= 100 )
        return 3;
    else if ( turnaround_time <= 500 )
        return 4;
    else if ( turnaround_time <= 1000 )
        return 5;
    else if ( turnaround_time <= 5000 )
        return 6;
    else
        return 7;
}


/*------------------------------------------------------------------*/
/*
 * Send a command to change the speed of the dongle
 * Need to be called with spinlock on.
 */
static void irda_usb_change_speed_xbofs(struct irda_usb_cb *self)
{
    __u8 *frame;
    struct urb *urb;
    int ret;

    IRDA_DEBUG(2, "%s(), speed=%d, xbofs=%d\n", __func__,
           self->new_speed, self->new_xbofs);

    /* Grab the speed URB */
    urb = self->speed_urb;
    if (urb->status != 0) {
        IRDA_WARNING("%s(), URB still in use!\n", __func__);
        return;
    }

    /* Allocate the fake frame */
    frame = self->speed_buff;

    /* Set the new speed and xbofs in this fake frame */
    irda_usb_build_header(self, frame, 1);

    if (self->capability & IUC_STIR421X) {
        if (frame[0] == 0) return ; // do nothing if no change
        frame[1] = 0; // other parameters don't change here
        frame[2] = 0;
    }

    /* Submit the 0 length IrDA frame to trigger new speed settings */
        usb_fill_bulk_urb(urb, self->usbdev,
              usb_sndbulkpipe(self->usbdev, self->bulk_out_ep),
                      frame, IRDA_USB_SPEED_MTU,
                      speed_bulk_callback, self);
    urb->transfer_buffer_length = self->header_length;
    urb->transfer_flags = 0;

    /* Irq disabled -> GFP_ATOMIC */
    if ((ret = usb_submit_urb(urb, GFP_ATOMIC))) {
        IRDA_WARNING("%s(), failed Speed URB\n", __func__);
    }
}

/*------------------------------------------------------------------*/
/*
 * Speed URB callback
 * Now, we can only get called for the speed URB.
 */
static void speed_bulk_callback(struct urb *urb)
{
    struct irda_usb_cb *self = urb->context;
    
    IRDA_DEBUG(2, "%s()\n", __func__);

    /* We should always have a context */
    IRDA_ASSERT(self != NULL, return;);
    /* We should always be called for the speed URB */
    IRDA_ASSERT(urb == self->speed_urb, return;);

    /* Check for timeout and other USB nasties */
    if (urb->status != 0) {
        /* I get a lot of -ECONNABORTED = -103 here - Jean II */
        IRDA_DEBUG(0, "%s(), URB complete status %d, transfer_flags 0x%04X\n", __func__, urb->status, urb->transfer_flags);

        /* Don't do anything here, that might confuse the USB layer.
         * Instead, we will wait for irda_usb_net_timeout(), the
         * network layer watchdog, to fix the situation.
         * Jean II */
        /* A reset of the dongle might be welcomed here - Jean II */
        return;
    }

    /* urb is now available */
    //urb->status = 0; -> tested above

    /* New speed and xbof is now committed in hardware */
    self->new_speed = -1;
    self->new_xbofs = -1;

    /* Allow the stack to send more packets */
    netif_wake_queue(self->netdev);
}

/*------------------------------------------------------------------*/
/*
 * Send an IrDA frame to the USB dongle (for transmission)
 */
static netdev_tx_t irda_usb_hard_xmit(struct sk_buff *skb,
                        struct net_device *netdev)
{
    struct irda_usb_cb *self = netdev_priv(netdev);
    struct urb *urb = self->tx_urb;
    unsigned long flags;
    s32 speed;
    s16 xbofs;
    int res, mtt;

    IRDA_DEBUG(4, "%s() on %s\n", __func__, netdev->name);

    netif_stop_queue(netdev);

    /* Protect us from USB callbacks, net watchdog and else. */
    spin_lock_irqsave(&self->lock, flags);

    /* Check if the device is still there.
     * We need to check self->present under the spinlock because
     * of irda_usb_disconnect() is synchronous - Jean II */
    if (!self->present) {
        IRDA_DEBUG(0, "%s(), Device is gone...\n", __func__);
        goto drop;
    }

    /* Check if we need to change the number of xbofs */
        xbofs = irda_get_next_xbofs(skb);
        if ((xbofs != self->xbofs) && (xbofs != -1)) {
        self->new_xbofs = xbofs;
    }

        /* Check if we need to change the speed */
    speed = irda_get_next_speed(skb);
    if ((speed != self->speed) && (speed != -1)) {
        /* Set the desired speed */
        self->new_speed = speed;

        /* Check for empty frame */
        if (!skb->len) {
            /* IrLAP send us an empty frame to make us change the
             * speed. Changing speed with the USB adapter is in
             * fact sending an empty frame to the adapter, so we
             * could just let the present function do its job.
             * However, we would wait for min turn time,
             * do an extra memcpy and increment packet counters...
             * Jean II */
            irda_usb_change_speed_xbofs(self);
            netdev->trans_start = jiffies;
            /* Will netif_wake_queue() in callback */
            goto drop;
        }
    }

    if (urb->status != 0) {
        IRDA_WARNING("%s(), URB still in use!\n", __func__);
        goto drop;
    }

    skb_copy_from_linear_data(skb, self->tx_buff + self->header_length, skb->len);

    /* Change setting for next frame */
    if (self->capability & IUC_STIR421X) {
        __u8 turnaround_time;
        __u8* frame = self->tx_buff;
        turnaround_time = get_turnaround_time( skb );
        irda_usb_build_header(self, frame, 0);
        frame[2] = turnaround_time;
        if ((skb->len != 0) &&
            ((skb->len % 128) == 0) &&
            ((skb->len % 512) != 0)) {
            /* add extra byte for special SigmaTel feature */
            frame[1] = 1;
            skb_put(skb, 1);
        } else {
            frame[1] = 0;
        }
    } else {
        irda_usb_build_header(self, self->tx_buff, 0);
    }

    /* FIXME: Make macro out of this one */
    ((struct irda_skb_cb *)skb->cb)->context = self;

    usb_fill_bulk_urb(urb, self->usbdev,
              usb_sndbulkpipe(self->usbdev, self->bulk_out_ep),
                      self->tx_buff, skb->len + self->header_length,
                      write_bulk_callback, skb);

    /* This flag (URB_ZERO_PACKET) indicates that what we send is not
     * a continuous stream of data but separate packets.
     * In this case, the USB layer will insert an empty USB frame (TD)
     * after each of our packets that is exact multiple of the frame size.
     * This is how the dongle will detect the end of packet - Jean II */
    urb->transfer_flags = URB_ZERO_PACKET;

    /* Generate min turn time. FIXME: can we do better than this? */
    /* Trying to a turnaround time at this level is trying to measure
     * processor clock cycle with a wrist-watch, approximate at best...
     *
     * What we know is the last time we received a frame over USB.
     * Due to latency over USB that depend on the USB load, we don't
     * know when this frame was received over IrDA (a few ms before ?)
     * Then, same story for our outgoing frame...
     *
     * In theory, the USB dongle is supposed to handle the turnaround
     * by itself (spec 1.0, chater 4, page 6). Who knows ??? That's
     * why this code is enabled only for dongles that doesn't meet
     * the spec.
     * Jean II */
    if (self->capability & IUC_NO_TURN) {
        mtt = irda_get_mtt(skb);
        if (mtt) {
            int diff;
            do_gettimeofday(&self->now);
            diff = self->now.tv_usec - self->stamp.tv_usec;
#ifdef IU_USB_MIN_RTT
            /* Factor in USB delays -> Get rid of udelay() that
             * would be lost in the noise - Jean II */
            diff += IU_USB_MIN_RTT;
#endif /* IU_USB_MIN_RTT */
            /* If the usec counter did wraparound, the diff will
             * go negative (tv_usec is a long), so we need to
             * correct it by one second. Jean II */
            if (diff < 0)
                diff += 1000000;

                /* Check if the mtt is larger than the time we have
             * already used by all the protocol processing
             */
            if (mtt > diff) {
                mtt -= diff;
                if (mtt > 1000)
                    mdelay(mtt/1000);
                else
                    udelay(mtt);
            }
        }
    }
    
    /* Ask USB to send the packet - Irq disabled -> GFP_ATOMIC */
    if ((res = usb_submit_urb(urb, GFP_ATOMIC))) {
        IRDA_WARNING("%s(), failed Tx URB\n", __func__);
        netdev->stats.tx_errors++;
        /* Let USB recover : We will catch that in the watchdog */
        /*netif_start_queue(netdev);*/
    } else {
        /* Increment packet stats */
        netdev->stats.tx_packets++;
                netdev->stats.tx_bytes += skb->len;
        
        netdev->trans_start = jiffies;
    }
    spin_unlock_irqrestore(&self->lock, flags);
    
    return NETDEV_TX_OK;

drop:
    /* Drop silently the skb and exit */
    dev_kfree_skb(skb);
    spin_unlock_irqrestore(&self->lock, flags);
    return NETDEV_TX_OK;
}

/*------------------------------------------------------------------*/
/*
 * Note : this function will be called only for tx_urb...
 */
static void write_bulk_callback(struct urb *urb)
{
    unsigned long flags;
    struct sk_buff *skb = urb->context;
    struct irda_usb_cb *self = ((struct irda_skb_cb *) skb->cb)->context;
    
    IRDA_DEBUG(2, "%s()\n", __func__);

    /* We should always have a context */
    IRDA_ASSERT(self != NULL, return;);
    /* We should always be called for the speed URB */
    IRDA_ASSERT(urb == self->tx_urb, return;);

    /* Free up the skb */
    dev_kfree_skb_any(skb);
    urb->context = NULL;

    /* Check for timeout and other USB nasties */
    if (urb->status != 0) {
        /* I get a lot of -ECONNABORTED = -103 here - Jean II */
        IRDA_DEBUG(0, "%s(), URB complete status %d, transfer_flags 0x%04X\n", __func__, urb->status, urb->transfer_flags);

        /* Don't do anything here, that might confuse the USB layer,
         * and we could go in recursion and blow the kernel stack...
         * Instead, we will wait for irda_usb_net_timeout(), the
         * network layer watchdog, to fix the situation.
         * Jean II */
        /* A reset of the dongle might be welcomed here - Jean II */
        return;
    }

    /* urb is now available */
    //urb->status = 0; -> tested above

    /* Make sure we read self->present properly */
    spin_lock_irqsave(&self->lock, flags);

    /* If the network is closed, stop everything */
    if ((!self->netopen) || (!self->present)) {
        IRDA_DEBUG(0, "%s(), Network is gone...\n", __func__);
        spin_unlock_irqrestore(&self->lock, flags);
        return;
    }

    /* If changes to speed or xbofs is pending... */
    if ((self->new_speed != -1) || (self->new_xbofs != -1)) {
        if ((self->new_speed != self->speed) ||
            (self->new_xbofs != self->xbofs)) {
            /* We haven't changed speed yet (because of
             * IUC_SPEED_BUG), so do it now - Jean II */
            IRDA_DEBUG(1, "%s(), Changing speed now...\n", __func__);
            irda_usb_change_speed_xbofs(self);
        } else {
            /* New speed and xbof is now committed in hardware */
            self->new_speed = -1;
            self->new_xbofs = -1;
            /* Done, waiting for next packet */
            netif_wake_queue(self->netdev);
        }
    } else {
        /* Otherwise, allow the stack to send more packets */
        netif_wake_queue(self->netdev);
    }
    spin_unlock_irqrestore(&self->lock, flags);
}

/*------------------------------------------------------------------*/
/*
 * Watchdog timer from the network layer.
 * After a predetermined timeout, if we don't give confirmation that
 * the packet has been sent (i.e. no call to netif_wake_queue()),
 * the network layer will call this function.
 * Note that URB that we submit have also a timeout. When the URB timeout
 * expire, the normal URB callback is called (write_bulk_callback()).
 */
static void irda_usb_net_timeout(struct net_device *netdev)
{
    unsigned long flags;
    struct irda_usb_cb *self = netdev_priv(netdev);
    struct urb *urb;
    int done = 0;   /* If we have made any progress */

    IRDA_DEBUG(0, "%s(), Network layer thinks we timed out!\n", __func__);
    IRDA_ASSERT(self != NULL, return;);

    /* Protect us from USB callbacks, net Tx and else. */
    spin_lock_irqsave(&self->lock, flags);

    /* self->present *MUST* be read under spinlock */
    if (!self->present) {
        IRDA_WARNING("%s(), device not present!\n", __func__);
        netif_stop_queue(netdev);
        spin_unlock_irqrestore(&self->lock, flags);
        return;
    }

    /* Check speed URB */
    urb = self->speed_urb;
    if (urb->status != 0) {
        IRDA_DEBUG(0, "%s: Speed change timed out, urb->status=%d, urb->transfer_flags=0x%04X\n", netdev->name, urb->status, urb->transfer_flags);

        switch (urb->status) {
        case -EINPROGRESS:
            usb_unlink_urb(urb);
            /* Note : above will  *NOT* call netif_wake_queue()
             * in completion handler, we will come back here.
             * Jean II */
            done = 1;
            break;
        case -ECONNRESET:
        case -ENOENT:           /* urb unlinked by us */
        default:            /* ??? - Play safe */
            urb->status = 0;
            netif_wake_queue(self->netdev);
            done = 1;
            break;
        }
    }

    /* Check Tx URB */
    urb = self->tx_urb;
    if (urb->status != 0) {
        struct sk_buff *skb = urb->context;

        IRDA_DEBUG(0, "%s: Tx timed out, urb->status=%d, urb->transfer_flags=0x%04X\n", netdev->name, urb->status, urb->transfer_flags);

        /* Increase error count */
        netdev->stats.tx_errors++;

#ifdef IU_BUG_KICK_TIMEOUT
        /* Can't be a bad idea to reset the speed ;-) - Jean II */
        if(self->new_speed == -1)
            self->new_speed = self->speed;
        if(self->new_xbofs == -1)
            self->new_xbofs = self->xbofs;
        irda_usb_change_speed_xbofs(self);
#endif /* IU_BUG_KICK_TIMEOUT */

        switch (urb->status) {
        case -EINPROGRESS:
            usb_unlink_urb(urb);
            /* Note : above will  *NOT* call netif_wake_queue()
             * in completion handler, because urb->status will
             * be -ENOENT. We will fix that at the next watchdog,
             * leaving more time to USB to recover...
             * Jean II */
            done = 1;
            break;
        case -ECONNRESET:
        case -ENOENT:           /* urb unlinked by us */
        default:            /* ??? - Play safe */
            if(skb != NULL) {
                dev_kfree_skb_any(skb);
                urb->context = NULL;
            }
            urb->status = 0;
            netif_wake_queue(self->netdev);
            done = 1;
            break;
        }
    }
    spin_unlock_irqrestore(&self->lock, flags);

    /* Maybe we need a reset */
    /* Note : Some drivers seem to use a usb_set_interface() when they
     * need to reset the hardware. Hum...
     */

    /* if(done == 0) */
}

/************************* RECEIVE ROUTINES *************************/
/*
 * Receive packets from the USB layer stack and pass them to the IrDA stack.
 * Try to work around USB failures...
 */

/*
 * Note :
 * Some of you may have noticed that most dongle have an interrupt in pipe
 * that we don't use. Here is the little secret...
 * When we hang a Rx URB on the bulk in pipe, it generates some USB traffic
 * in every USB frame. This is unnecessary overhead.
 * The interrupt in pipe will generate an event every time a packet is
 * received. Reading an interrupt pipe adds minimal overhead, but has some
 * latency (~1ms).
 * If we are connected (speed != 9600), we want to minimise latency, so
 * we just always hang the Rx URB and ignore the interrupt.
 * If we are not connected (speed == 9600), there is usually no Rx traffic,
 * and we want to minimise the USB overhead. In this case we should wait
 * on the interrupt pipe and hang the Rx URB only when an interrupt is
 * received.
 * Jean II
 *
 * Note : don't read the above as what we are currently doing, but as
 * something we could do with KC dongle. Also don't forget that the
 * interrupt pipe is not part of the original standard, so this would
 * need to be optional...
 * Jean II
 */

/*------------------------------------------------------------------*/
/*
 * Submit a Rx URB to the USB layer to handle reception of a frame
 * Mostly called by the completion callback of the previous URB.
 *
 * Jean II
 */
static void irda_usb_submit(struct irda_usb_cb *self, struct sk_buff *skb, struct urb *urb)
{
    struct irda_skb_cb *cb;
    int ret;

    IRDA_DEBUG(2, "%s()\n", __func__);

    /* This should never happen */
    IRDA_ASSERT(skb != NULL, return;);
    IRDA_ASSERT(urb != NULL, return;);

    /* Save ourselves in the skb */
    cb = (struct irda_skb_cb *) skb->cb;
    cb->context = self;

    /* Reinitialize URB */
    usb_fill_bulk_urb(urb, self->usbdev, 
              usb_rcvbulkpipe(self->usbdev, self->bulk_in_ep), 
              skb->data, IRDA_SKB_MAX_MTU,
                      irda_usb_receive, skb);
    urb->status = 0;

    /* Can be called from irda_usb_receive (irq handler) -> GFP_ATOMIC */
    ret = usb_submit_urb(urb, GFP_ATOMIC);
    if (ret) {
        /* If this ever happen, we are in deep s***.
         * Basically, the Rx path will stop... */
        IRDA_WARNING("%s(), Failed to submit Rx URB %d\n",
                 __func__, ret);
    }
}

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_receive(urb)
 *
 *     Called by the USB subsystem when a frame has been received
 *
 */
static void irda_usb_receive(struct urb *urb)
{
    struct sk_buff *skb = (struct sk_buff *) urb->context;
    struct irda_usb_cb *self; 
    struct irda_skb_cb *cb;
    struct sk_buff *newskb;
    struct sk_buff *dataskb;
    struct urb *next_urb;
    unsigned int len, docopy;

    IRDA_DEBUG(2, "%s(), len=%d\n", __func__, urb->actual_length);
    
    /* Find ourselves */
    cb = (struct irda_skb_cb *) skb->cb;
    IRDA_ASSERT(cb != NULL, return;);
    self = (struct irda_usb_cb *) cb->context;
    IRDA_ASSERT(self != NULL, return;);

    /* If the network is closed or the device gone, stop everything */
    if ((!self->netopen) || (!self->present)) {
        IRDA_DEBUG(0, "%s(), Network is gone!\n", __func__);
        /* Don't re-submit the URB : will stall the Rx path */
        return;
    }
    
    /* Check the status */
    if (urb->status != 0) {
        switch (urb->status) {
        case -EILSEQ:
            self->netdev->stats.rx_crc_errors++;
            /* Also precursor to a hot-unplug on UHCI. */
            /* Fallthrough... */
        case -ECONNRESET:
            /* Random error, if I remember correctly */
            /* uhci_cleanup_unlink() is going to kill the Rx
             * URB just after we return. No problem, at this
             * point the URB will be idle ;-) - Jean II */
        case -ESHUTDOWN:
            /* That's usually a hot-unplug. Submit will fail... */
        case -ETIME:
            /* Usually precursor to a hot-unplug on OHCI. */
        default:
            self->netdev->stats.rx_errors++;
            IRDA_DEBUG(0, "%s(), RX status %d, transfer_flags 0x%04X\n", __func__, urb->status, urb->transfer_flags);
            break;
        }
        /* If we received an error, we don't want to resubmit the
         * Rx URB straight away but to give the USB layer a little
         * bit of breathing room.
         * We are in the USB thread context, therefore there is a
         * danger of recursion (new URB we submit fails, we come
         * back here).
         * With recent USB stack (2.6.15+), I'm seeing that on
         * hot unplug of the dongle...
         * Lowest effective timer is 10ms...
         * Jean II */
        self->rx_defer_timer.function = irda_usb_rx_defer_expired;
        self->rx_defer_timer.data = (unsigned long) urb;
        mod_timer(&self->rx_defer_timer, jiffies + (10 * HZ / 1000));
        return;
    }
    
    /* Check for empty frames */
    if (urb->actual_length <= self->header_length) {
        IRDA_WARNING("%s(), empty frame!\n", __func__);
        goto done;
    }

    /*  
     * Remember the time we received this frame, so we can
     * reduce the min turn time a bit since we will know
     * how much time we have used for protocol processing
     */
        do_gettimeofday(&self->stamp);

    /* Check if we need to copy the data to a new skb or not.
     * For most frames, we use ZeroCopy and pass the already
     * allocated skb up the stack.
     * If the frame is small, it is more efficient to copy it
     * to save memory (copy will be fast anyway - that's
     * called Rx-copy-break). Jean II */
    docopy = (urb->actual_length < IRDA_RX_COPY_THRESHOLD);

    /* Allocate a new skb */
    if (self->capability & IUC_STIR421X)
        newskb = dev_alloc_skb(docopy ? urb->actual_length :
                       IRDA_SKB_MAX_MTU +
                       USB_IRDA_STIR421X_HEADER);
    else
        newskb = dev_alloc_skb(docopy ? urb->actual_length :
                       IRDA_SKB_MAX_MTU);

    if (!newskb)  {
        self->netdev->stats.rx_dropped++;
        /* We could deliver the current skb, but this would stall
         * the Rx path. Better drop the packet... Jean II */
        goto done;  
    }

    /* Make sure IP header get aligned (IrDA header is 5 bytes) */
    /* But IrDA-USB header is 1 byte. Jean II */
    //skb_reserve(newskb, USB_IRDA_HEADER - 1);

    if(docopy) {
        /* Copy packet, so we can recycle the original */
        skb_copy_from_linear_data(skb, newskb->data, urb->actual_length);
        /* Deliver this new skb */
        dataskb = newskb;
        /* And hook the old skb to the URB
         * Note : we don't need to "clean up" the old skb,
         * as we never touched it. Jean II */
    } else {
        /* We are using ZeroCopy. Deliver old skb */
        dataskb = skb;
        /* And hook the new skb to the URB */
        skb = newskb;
    }

    /* Set proper length on skb & remove USB-IrDA header */
    skb_put(dataskb, urb->actual_length);
    skb_pull(dataskb, self->header_length);

    /* Ask the networking layer to queue the packet for the IrDA stack */
    dataskb->dev = self->netdev;
    skb_reset_mac_header(dataskb);
    dataskb->protocol = htons(ETH_P_IRDA);
    len = dataskb->len;
    netif_rx(dataskb);

    /* Keep stats up to date */
    self->netdev->stats.rx_bytes += len;
    self->netdev->stats.rx_packets++;

done:
    /* Note : at this point, the URB we've just received (urb)
     * is still referenced by the USB layer. For example, if we
     * have received a -ECONNRESET, uhci_cleanup_unlink() will
     * continue to process it (in fact, cleaning it up).
     * If we were to submit this URB, disaster would ensue.
     * Therefore, we submit our idle URB, and put this URB in our
     * idle slot....
     * Jean II */
    /* Note : with this scheme, we could submit the idle URB before
     * processing the Rx URB. I don't think it would buy us anything as
     * we are running in the USB thread context. Jean II */
    next_urb = self->idle_rx_urb;

    /* Recycle Rx URB : Now, the idle URB is the present one */
    urb->context = NULL;
    self->idle_rx_urb = urb;

    /* Submit the idle URB to replace the URB we've just received.
     * Do it last to avoid race conditions... Jean II */
    irda_usb_submit(self, skb, next_urb);
}

/*------------------------------------------------------------------*/
/*
 * In case of errors, we want the USB layer to have time to recover.
 * Now, it is time to resubmit ouur Rx URB...
 */
static void irda_usb_rx_defer_expired(unsigned long data)
{
    struct urb *urb = (struct urb *) data;
    struct sk_buff *skb = (struct sk_buff *) urb->context;
    struct irda_usb_cb *self; 
    struct irda_skb_cb *cb;
    struct urb *next_urb;

    IRDA_DEBUG(2, "%s()\n", __func__);

    /* Find ourselves */
    cb = (struct irda_skb_cb *) skb->cb;
    IRDA_ASSERT(cb != NULL, return;);
    self = (struct irda_usb_cb *) cb->context;
    IRDA_ASSERT(self != NULL, return;);

    /* Same stuff as when Rx is done, see above... */
    next_urb = self->idle_rx_urb;
    urb->context = NULL;
    self->idle_rx_urb = urb;
    irda_usb_submit(self, skb, next_urb);
}

/*------------------------------------------------------------------*/
/*
 * Callbak from IrDA layer. IrDA wants to know if we have
 * started receiving anything.
 */
static int irda_usb_is_receiving(struct irda_usb_cb *self)
{
    /* Note : because of the way UHCI works, it's almost impossible
     * to get this info. The Controller DMA directly to memory and
     * signal only when the whole frame is finished. To know if the
     * first TD of the URB has been filled or not seems hard work...
     *
     * The other solution would be to use the "receiving" command
     * on the default decriptor with a usb_control_msg(), but that
     * would add USB traffic and would return result only in the
     * next USB frame (~1ms).
     *
     * I've been told that current dongles send status info on their
     * interrupt endpoint, and that's what the Windows driver uses
     * to know this info. Unfortunately, this is not yet in the spec...
     *
     * Jean II
     */

    return 0; /* For now */
}

#define STIR421X_PATCH_PRODUCT_VER     "Product Version: "
#define STIR421X_PATCH_STMP_TAG        "STMP"
#define STIR421X_PATCH_CODE_OFFSET     512 /* patch image starts before here */
/* marks end of patch file header (PC DOS text file EOF character) */
#define STIR421X_PATCH_END_OF_HDR_TAG  0x1A
#define STIR421X_PATCH_BLOCK_SIZE      1023

/*
 * Function stir421x_fwupload (struct irda_usb_cb *self,
 *                             unsigned char *patch,
 *                             const unsigned int patch_len)
 *
 *   Upload firmware code to SigmaTel 421X IRDA-USB dongle
 */
static int stir421x_fw_upload(struct irda_usb_cb *self,
                 const unsigned char *patch,
                 const unsigned int patch_len)
{
        int ret = -ENOMEM;
        int actual_len = 0;
        unsigned int i;
        unsigned int block_size = 0;
        unsigned char *patch_block;

        patch_block = kzalloc(STIR421X_PATCH_BLOCK_SIZE, GFP_KERNEL);
    if (patch_block == NULL)
        return -ENOMEM;

    /* break up patch into 1023-byte sections */
    for (i = 0; i < patch_len; i += block_size) {
        block_size = patch_len - i;

        if (block_size > STIR421X_PATCH_BLOCK_SIZE)
            block_size = STIR421X_PATCH_BLOCK_SIZE;

        /* upload the patch section */
        memcpy(patch_block, patch + i, block_size);

        ret = usb_bulk_msg(self->usbdev,
                   usb_sndbulkpipe(self->usbdev,
                           self->bulk_out_ep),
                   patch_block, block_size,
                   &actual_len, msecs_to_jiffies(500));
        IRDA_DEBUG(3,"%s(): Bulk send %u bytes, ret=%d\n",
               __func__, actual_len, ret);

        if (ret < 0)
            break;

        mdelay(10);
    }

    kfree(patch_block);

        return ret;
 }

/*
 * Function stir421x_patch_device(struct irda_usb_cb *self)
 *
 * Get a firmware code from userspase using hotplug request_firmware() call
  */
static int stir421x_patch_device(struct irda_usb_cb *self)
{
    unsigned int i;
    int ret;
    char stir421x_fw_name[12];
    const struct firmware *fw;
    const unsigned char *fw_version_ptr; /* pointer to version string */
    unsigned long fw_version = 0;

        /*
         * Known firmware patch file names for STIR421x dongles
         * are "42101001.sb" or "42101002.sb"
         */
        sprintf(stir421x_fw_name, "4210%4X.sb",
                self->usbdev->descriptor.bcdDevice);
        ret = request_firmware(&fw, stir421x_fw_name, &self->usbdev->dev);
        if (ret < 0)
                return ret;

        /* We get a patch from userspace */
        IRDA_MESSAGE("%s(): Received firmware %s (%zu bytes)\n",
                     __func__, stir421x_fw_name, fw->size);

        ret = -EINVAL;

    /* Get the bcd product version */
        if (!memcmp(fw->data, STIR421X_PATCH_PRODUCT_VER,
                    sizeof(STIR421X_PATCH_PRODUCT_VER) - 1)) {
                fw_version_ptr = fw->data +
            sizeof(STIR421X_PATCH_PRODUCT_VER) - 1;

                /* Let's check if the product version is dotted */
                if (fw_version_ptr[3] == '.' &&
            fw_version_ptr[7] == '.') {
            unsigned long major, minor, build;
            major = simple_strtoul(fw_version_ptr, NULL, 10);
            minor = simple_strtoul(fw_version_ptr + 4, NULL, 10);
            build = simple_strtoul(fw_version_ptr + 8, NULL, 10);

            fw_version = (major << 12)
                + (minor << 8)
                + ((build / 10) << 4)
                + (build % 10);

            IRDA_DEBUG(3, "%s(): Firmware Product version %ld\n",
                                   __func__, fw_version);
                }
        }

        if (self->usbdev->descriptor.bcdDevice == cpu_to_le16(fw_version)) {
                /*
         * If we're here, we've found a correct patch
                 * The actual image starts after the "STMP" keyword
                 * so forward to the firmware header tag
                 */
                for (i = 0; i < fw->size && fw->data[i] !=
                 STIR421X_PATCH_END_OF_HDR_TAG; i++) ;
                /* here we check for the out of buffer case */
                if (i < STIR421X_PATCH_CODE_OFFSET && i < fw->size &&
                STIR421X_PATCH_END_OF_HDR_TAG == fw->data[i]) {
                        if (!memcmp(fw->data + i + 1, STIR421X_PATCH_STMP_TAG,
                                    sizeof(STIR421X_PATCH_STMP_TAG) - 1)) {

                /* We can upload the patch to the target */
                i += sizeof(STIR421X_PATCH_STMP_TAG);
                                ret = stir421x_fw_upload(self, &fw->data[i],
                             fw->size - i);
                        }
                }
        }

        release_firmware(fw);

        return ret;
}


/********************** IRDA DEVICE CALLBACKS **********************/
/*
 * Main calls from the IrDA/Network subsystem.
 * Mostly registering a new irda-usb device and removing it....
 * We only deal with the IrDA side of the business, the USB side will
 * be dealt with below...
 */


/*------------------------------------------------------------------*/
/*
 * Function irda_usb_net_open (dev)
 *
 *    Network device is taken up. Usually this is done by "ifconfig irda0 up" 
 *   
 * Note : don't mess with self->netopen - Jean II
 */
static int irda_usb_net_open(struct net_device *netdev)
{
    struct irda_usb_cb *self;
    unsigned long flags;
    char    hwname[16];
    int i;
    
    IRDA_DEBUG(1, "%s()\n", __func__);

    IRDA_ASSERT(netdev != NULL, return -1;);
    self = netdev_priv(netdev);
    IRDA_ASSERT(self != NULL, return -1;);

    spin_lock_irqsave(&self->lock, flags);
    /* Can only open the device if it's there */
    if(!self->present) {
        spin_unlock_irqrestore(&self->lock, flags);
        IRDA_WARNING("%s(), device not present!\n", __func__);
        return -1;
    }

    if(self->needspatch) {
        spin_unlock_irqrestore(&self->lock, flags);
        IRDA_WARNING("%s(), device needs patch\n", __func__) ;
        return -EIO ;
    }

    /* Initialise default speed and xbofs value
     * (IrLAP will change that soon) */
    self->speed = -1;
    self->xbofs = -1;
    self->new_speed = -1;
    self->new_xbofs = -1;

    /* To do *before* submitting Rx urbs and starting net Tx queue
     * Jean II */
    self->netopen = 1;
    spin_unlock_irqrestore(&self->lock, flags);

    /* 
     * Now that everything should be initialized properly,
     * Open new IrLAP layer instance to take care of us...
     * Note : will send immediately a speed change...
     */
    sprintf(hwname, "usb#%d", self->usbdev->devnum);
    self->irlap = irlap_open(netdev, &self->qos, hwname);
    IRDA_ASSERT(self->irlap != NULL, return -1;);

    /* Allow IrLAP to send data to us */
    netif_start_queue(netdev);

    /* We submit all the Rx URB except for one that we keep idle.
     * Need to be initialised before submitting other USBs, because
     * in some cases as soon as we submit the URBs the USB layer
     * will trigger a dummy receive - Jean II */
    self->idle_rx_urb = self->rx_urb[IU_MAX_ACTIVE_RX_URBS];
    self->idle_rx_urb->context = NULL;

    /* Now that we can pass data to IrLAP, allow the USB layer
     * to send us some data... */
    for (i = 0; i < IU_MAX_ACTIVE_RX_URBS; i++) {
        struct sk_buff *skb = dev_alloc_skb(IRDA_SKB_MAX_MTU);
        if (!skb) {
            /* If this ever happen, we are in deep s***.
             * Basically, we can't start the Rx path... */
            IRDA_WARNING("%s(), Failed to allocate Rx skb\n",
                     __func__);
            return -1;
        }
        //skb_reserve(newskb, USB_IRDA_HEADER - 1);
        irda_usb_submit(self, skb, self->rx_urb[i]);
    }

    /* Ready to play !!! */
    return 0;
}

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_net_close (self)
 *
 *    Network device is taken down. Usually this is done by 
 *    "ifconfig irda0 down" 
 */
static int irda_usb_net_close(struct net_device *netdev)
{
    struct irda_usb_cb *self;
    int i;

    IRDA_DEBUG(1, "%s()\n", __func__);

    IRDA_ASSERT(netdev != NULL, return -1;);
    self = netdev_priv(netdev);
    IRDA_ASSERT(self != NULL, return -1;);

    /* Clear this flag *before* unlinking the urbs and *before*
     * stopping the network Tx queue - Jean II */
    self->netopen = 0;

    /* Stop network Tx queue */
    netif_stop_queue(netdev);

    /* Kill defered Rx URB */
    del_timer(&self->rx_defer_timer);

    /* Deallocate all the Rx path buffers (URBs and skb) */
    for (i = 0; i < self->max_rx_urb; i++) {
        struct urb *urb = self->rx_urb[i];
        struct sk_buff *skb = (struct sk_buff *) urb->context;
        /* Cancel the receive command */
        usb_kill_urb(urb);
        /* The skb is ours, free it */
        if(skb) {
            dev_kfree_skb(skb);
            urb->context = NULL;
        }
    }
    /* Cancel Tx and speed URB - need to be synchronous to avoid races */
    usb_kill_urb(self->tx_urb);
    usb_kill_urb(self->speed_urb);

    /* Stop and remove instance of IrLAP */
    if (self->irlap)
        irlap_close(self->irlap);
    self->irlap = NULL;

    return 0;
}

/*------------------------------------------------------------------*/
/*
 * IOCTLs : Extra out-of-band network commands...
 */
static int irda_usb_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
    unsigned long flags;
    struct if_irda_req *irq = (struct if_irda_req *) rq;
    struct irda_usb_cb *self;
    int ret = 0;

    IRDA_ASSERT(dev != NULL, return -1;);
    self = netdev_priv(dev);
    IRDA_ASSERT(self != NULL, return -1;);

    IRDA_DEBUG(2, "%s(), %s, (cmd=0x%X)\n", __func__, dev->name, cmd);

    switch (cmd) {
    case SIOCSBANDWIDTH: /* Set bandwidth */
        if (!capable(CAP_NET_ADMIN))
            return -EPERM;
        /* Protect us from USB callbacks, net watchdog and else. */
        spin_lock_irqsave(&self->lock, flags);
        /* Check if the device is still there */
        if(self->present) {
            /* Set the desired speed */
            self->new_speed = irq->ifr_baudrate;
            irda_usb_change_speed_xbofs(self);
        }
        spin_unlock_irqrestore(&self->lock, flags);
        break;
    case SIOCSMEDIABUSY: /* Set media busy */
        if (!capable(CAP_NET_ADMIN))
            return -EPERM;
        /* Check if the IrDA stack is still there */
        if(self->netopen)
            irda_device_set_media_busy(self->netdev, TRUE);
        break;
    case SIOCGRECEIVING: /* Check if we are receiving right now */
        irq->ifr_receiving = irda_usb_is_receiving(self);
        break;
    default:
        ret = -EOPNOTSUPP;
    }
    
    return ret;
}

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

/********************* IRDA CONFIG SUBROUTINES *********************/
/*
 * Various subroutines dealing with IrDA and network stuff we use to
 * configure and initialise each irda-usb instance.
 * These functions are used below in the main calls of the driver...
 */

/*------------------------------------------------------------------*/
/*
 * Set proper values in the IrDA QOS structure
 */
static inline void irda_usb_init_qos(struct irda_usb_cb *self)
{
    struct irda_class_desc *desc;

    IRDA_DEBUG(3, "%s()\n", __func__);
    
    desc = self->irda_desc;
    
    /* Initialize QoS for this device */
    irda_init_max_qos_capabilies(&self->qos);

    /* See spec section 7.2 for meaning.
     * Values are little endian (as most USB stuff), the IrDA stack
     * use it in native order (see parameters.c). - Jean II */
    self->qos.baud_rate.bits       = le16_to_cpu(desc->wBaudRate);
    self->qos.min_turn_time.bits   = desc->bmMinTurnaroundTime;
    self->qos.additional_bofs.bits = desc->bmAdditionalBOFs;
    self->qos.window_size.bits     = desc->bmWindowSize;
    self->qos.data_size.bits       = desc->bmDataSize;

    IRDA_DEBUG(0, "%s(), dongle says speed=0x%X, size=0x%X, window=0x%X, bofs=0x%X, turn=0x%X\n", 
        __func__, self->qos.baud_rate.bits, self->qos.data_size.bits, self->qos.window_size.bits, self->qos.additional_bofs.bits, self->qos.min_turn_time.bits);

    /* Don't always trust what the dongle tell us */
    if(self->capability & IUC_SIR_ONLY)
        self->qos.baud_rate.bits    &= 0x00ff;
    if(self->capability & IUC_SMALL_PKT)
        self->qos.data_size.bits     = 0x07;
    if(self->capability & IUC_NO_WINDOW)
        self->qos.window_size.bits   = 0x01;
    if(self->capability & IUC_MAX_WINDOW)
        self->qos.window_size.bits   = 0x7f;
    if(self->capability & IUC_MAX_XBOFS)
        self->qos.additional_bofs.bits   = 0x01;

#if 1
    /* Module parameter can override the rx window size */
    if (qos_mtt_bits)
        self->qos.min_turn_time.bits = qos_mtt_bits;
#endif      
    /* 
     * Note : most of those values apply only for the receive path,
     * the transmit path will be set differently - Jean II 
     */
    irda_qos_bits_to_value(&self->qos);
}

/*------------------------------------------------------------------*/
static const struct net_device_ops irda_usb_netdev_ops = {
    .ndo_open       = irda_usb_net_open,
    .ndo_stop       = irda_usb_net_close,
    .ndo_do_ioctl   = irda_usb_net_ioctl,
    .ndo_start_xmit = irda_usb_hard_xmit,
    .ndo_tx_timeout = irda_usb_net_timeout,
};

/*
 * Initialise the network side of the irda-usb instance
 * Called when a new USB instance is registered in irda_usb_probe()
 */
static inline int irda_usb_open(struct irda_usb_cb *self)
{
    struct net_device *netdev = self->netdev;

    IRDA_DEBUG(1, "%s()\n", __func__);

    netdev->netdev_ops = &irda_usb_netdev_ops;

    irda_usb_init_qos(self);

    return register_netdev(netdev);
}

/*------------------------------------------------------------------*/
/*
 * Cleanup the network side of the irda-usb instance
 * Called when a USB instance is removed in irda_usb_disconnect()
 */
static inline void irda_usb_close(struct irda_usb_cb *self)
{
    IRDA_DEBUG(1, "%s()\n", __func__);

    /* Remove netdevice */
    unregister_netdev(self->netdev);

    /* Remove the speed buffer */
    kfree(self->speed_buff);
    self->speed_buff = NULL;

    kfree(self->tx_buff);
    self->tx_buff = NULL;
}

/********************** USB CONFIG SUBROUTINES **********************/
/*
 * Various subroutines dealing with USB stuff we use to configure and
 * initialise each irda-usb instance.
 * These functions are used below in the main calls of the driver...
 */

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_parse_endpoints(dev, ifnum)
 *
 *    Parse the various endpoints and find the one we need.
 *
 * The endpoint are the pipes used to communicate with the USB device.
 * The spec defines 2 endpoints of type bulk transfer, one in, and one out.
 * These are used to pass frames back and forth with the dongle.
 * Most dongle have also an interrupt endpoint, that will be probably
 * documented in the next spec...
 */
static inline int irda_usb_parse_endpoints(struct irda_usb_cb *self, struct usb_host_endpoint *endpoint, int ennum)
{
    int i;      /* Endpoint index in table */
        
    /* Init : no endpoints */
    self->bulk_in_ep = 0;
    self->bulk_out_ep = 0;
    self->bulk_int_ep = 0;

    /* Let's look at all those endpoints */
    for(i = 0; i < ennum; i++) {
        /* All those variables will get optimised by the compiler,
         * so let's aim for clarity... - Jean II */
        __u8 ep;    /* Endpoint address */
        __u8 dir;   /* Endpoint direction */
        __u8 attr;  /* Endpoint attribute */
        __u16 psize;    /* Endpoint max packet size in bytes */

        /* Get endpoint address, direction and attribute */
        ep = endpoint[i].desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
        dir = endpoint[i].desc.bEndpointAddress & USB_ENDPOINT_DIR_MASK;
        attr = endpoint[i].desc.bmAttributes;
        psize = le16_to_cpu(endpoint[i].desc.wMaxPacketSize);

        /* Is it a bulk endpoint ??? */
        if(attr == USB_ENDPOINT_XFER_BULK) {
            /* We need to find an IN and an OUT */
            if(dir == USB_DIR_IN) {
                /* This is our Rx endpoint */
                self->bulk_in_ep = ep;
            } else {
                /* This is our Tx endpoint */
                self->bulk_out_ep = ep;
                self->bulk_out_mtu = psize;
            }
        } else {
            if((attr == USB_ENDPOINT_XFER_INT) &&
               (dir == USB_DIR_IN)) {
                /* This is our interrupt endpoint */
                self->bulk_int_ep = ep;
            } else {
                IRDA_ERROR("%s(), Unrecognised endpoint %02X.\n", __func__, ep);
            }
        }
    }

    IRDA_DEBUG(0, "%s(), And our endpoints are : in=%02X, out=%02X (%d), int=%02X\n",
        __func__, self->bulk_in_ep, self->bulk_out_ep, self->bulk_out_mtu, self->bulk_int_ep);

    return (self->bulk_in_ep != 0) && (self->bulk_out_ep != 0);
}

#ifdef IU_DUMP_CLASS_DESC
/*------------------------------------------------------------------*/
/*
 * Function usb_irda_dump_class_desc(desc)
 *
 *    Prints out the contents of the IrDA class descriptor
 *
 */
static inline void irda_usb_dump_class_desc(struct irda_class_desc *desc)
{
    /* Values are little endian */
    printk("bLength=%x\n", desc->bLength);
    printk("bDescriptorType=%x\n", desc->bDescriptorType);
    printk("bcdSpecRevision=%x\n", le16_to_cpu(desc->bcdSpecRevision)); 
    printk("bmDataSize=%x\n", desc->bmDataSize);
    printk("bmWindowSize=%x\n", desc->bmWindowSize);
    printk("bmMinTurnaroundTime=%d\n", desc->bmMinTurnaroundTime);
    printk("wBaudRate=%x\n", le16_to_cpu(desc->wBaudRate));
    printk("bmAdditionalBOFs=%x\n", desc->bmAdditionalBOFs);
    printk("bIrdaRateSniff=%x\n", desc->bIrdaRateSniff);
    printk("bMaxUnicastList=%x\n", desc->bMaxUnicastList);
}
#endif /* IU_DUMP_CLASS_DESC */

/*------------------------------------------------------------------*/
/*
 * Function irda_usb_find_class_desc(intf)
 *
 *    Returns instance of IrDA class descriptor, or NULL if not found
 *
 * The class descriptor is some extra info that IrDA USB devices will
 * offer to us, describing their IrDA characteristics. We will use that in
 * irda_usb_init_qos()
 */
static inline struct irda_class_desc *irda_usb_find_class_desc(struct usb_interface *intf)
{
    struct usb_device *dev = interface_to_usbdev (intf);
    struct irda_class_desc *desc;
    int ret;

    desc = kzalloc(sizeof(*desc), GFP_KERNEL);
    if (!desc)
        return NULL;

    /* USB-IrDA class spec 1.0:
     *  6.1.3: Standard "Get Descriptor" Device Request is not
     *         appropriate to retrieve class-specific descriptor
     *  6.2.5: Class Specific "Get Class Descriptor" Interface Request
     *         is mandatory and returns the USB-IrDA class descriptor
     */

    ret = usb_control_msg(dev, usb_rcvctrlpipe(dev,0),
        IU_REQ_GET_CLASS_DESC,
        USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
        0, intf->altsetting->desc.bInterfaceNumber, desc,
        sizeof(*desc), 500);
    
    IRDA_DEBUG(1, "%s(), ret=%d\n", __func__, ret);
    if (ret < sizeof(*desc)) {
        IRDA_WARNING("usb-irda: class_descriptor read %s (%d)\n",
                 (ret<0) ? "failed" : "too short", ret);
    }
    else if (desc->bDescriptorType != USB_DT_IRDA) {
        IRDA_WARNING("usb-irda: bad class_descriptor type\n");
    }
    else {
#ifdef IU_DUMP_CLASS_DESC
        irda_usb_dump_class_desc(desc);
#endif  /* IU_DUMP_CLASS_DESC */

        return desc;
    }
    kfree(desc);
    return NULL;
}

/*********************** USB DEVICE CALLBACKS ***********************/
/*
 * Main calls from the USB subsystem.
 * Mostly registering a new irda-usb device and removing it....
 */

/*------------------------------------------------------------------*/
/*
 * This routine is called by the USB subsystem for each new device
 * in the system. We need to check if the device is ours, and in
 * this case start handling it.
 * The USB layer protect us from reentrancy (via BKL), so we don't need
 * to spinlock in there... Jean II
 */
static int irda_usb_probe(struct usb_interface *intf,
              const struct usb_device_id *id)
{
    struct net_device *net;
    struct usb_device *dev = interface_to_usbdev(intf);
    struct irda_usb_cb *self;
    struct usb_host_interface *interface;
    struct irda_class_desc *irda_desc;
    int ret = -ENOMEM;
    int i;      /* Driver instance index / Rx URB index */

    /* Note : the probe make sure to call us only for devices that
     * matches the list of dongle (top of the file). So, we
     * don't need to check if the dongle is really ours.
     * Jean II */

    IRDA_MESSAGE("IRDA-USB found at address %d, Vendor: %x, Product: %x\n",
             dev->devnum, le16_to_cpu(dev->descriptor.idVendor),
             le16_to_cpu(dev->descriptor.idProduct));

    net = alloc_irdadev(sizeof(*self));
    if (!net) 
        goto err_out;

    SET_NETDEV_DEV(net, &intf->dev);
    self = netdev_priv(net);
    self->netdev = net;
    spin_lock_init(&self->lock);
    init_timer(&self->rx_defer_timer);

    self->capability = id->driver_info;
    self->needspatch = ((self->capability & IUC_STIR421X) != 0);

    /* Create all of the needed urbs */
    if (self->capability & IUC_STIR421X) {
        self->max_rx_urb = IU_SIGMATEL_MAX_RX_URBS;
        self->header_length = USB_IRDA_STIR421X_HEADER;
    } else {
        self->max_rx_urb = IU_MAX_RX_URBS;
        self->header_length = USB_IRDA_HEADER;
    }

    self->rx_urb = kcalloc(self->max_rx_urb, sizeof(struct urb *),
                GFP_KERNEL);
    if (!self->rx_urb)
        goto err_free_net;

    for (i = 0; i < self->max_rx_urb; i++) {
        self->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
        if (!self->rx_urb[i]) {
            goto err_out_1;
        }
    }
    self->tx_urb = usb_alloc_urb(0, GFP_KERNEL);
    if (!self->tx_urb) {
        goto err_out_1;
    }
    self->speed_urb = usb_alloc_urb(0, GFP_KERNEL);
    if (!self->speed_urb) {
        goto err_out_2;
    }

    /* Is this really necessary? (no, except maybe for broken devices) */
    if (usb_reset_configuration (dev) < 0) {
        dev_err(&intf->dev, "reset_configuration failed\n");
        ret = -EIO;
        goto err_out_3;
    }

    /* Is this really necessary? */
    /* Note : some driver do hardcode the interface number, some others
     * specify an alternate, but very few driver do like this.
     * Jean II */
    ret = usb_set_interface(dev, intf->altsetting->desc.bInterfaceNumber, 0);
    IRDA_DEBUG(1, "usb-irda: set interface %d result %d\n", intf->altsetting->desc.bInterfaceNumber, ret);
    switch (ret) {
        case 0:
            break;
        case -EPIPE:        /* -EPIPE = -32 */
            /* Martin Diehl says if we get a -EPIPE we should
             * be fine and we don't need to do a usb_clear_halt().
             * - Jean II */
            IRDA_DEBUG(0, "%s(), Received -EPIPE, ignoring...\n", __func__);
            break;
        default:
            IRDA_DEBUG(0, "%s(), Unknown error %d\n", __func__, ret);
            ret = -EIO;
            goto err_out_3;
    }

    /* Find our endpoints */
    interface = intf->cur_altsetting;
    if(!irda_usb_parse_endpoints(self, interface->endpoint,
                     interface->desc.bNumEndpoints)) {
        IRDA_ERROR("%s(), Bogus endpoints...\n", __func__);
        ret = -EIO;
        goto err_out_3;
    }

    self->usbdev = dev;

    /* Find IrDA class descriptor */
    irda_desc = irda_usb_find_class_desc(intf);
    ret = -ENODEV;
    if (!irda_desc)
        goto err_out_3;

    if (self->needspatch) {
        ret = usb_control_msg (self->usbdev, usb_sndctrlpipe (self->usbdev, 0),
                       0x02, 0x40, 0, 0, NULL, 0, 500);
        if (ret < 0) {
            IRDA_DEBUG (0, "usb_control_msg failed %d\n", ret);
            goto err_out_3;
        } else {
            mdelay(10);
        }
    }

    self->irda_desc =  irda_desc;
    self->present = 1;
    self->netopen = 0;
    self->usbintf = intf;

    /* Allocate the buffer for speed changes */
    /* Don't change this buffer size and allocation without doing
     * some heavy and complete testing. Don't ask why :-(
     * Jean II */
    self->speed_buff = kzalloc(IRDA_USB_SPEED_MTU, GFP_KERNEL);
    if (!self->speed_buff)
        goto err_out_3;

    self->tx_buff = kzalloc(IRDA_SKB_MAX_MTU + self->header_length,
                GFP_KERNEL);
    if (!self->tx_buff)
        goto err_out_4;

    ret = irda_usb_open(self);
    if (ret) 
        goto err_out_5;

    IRDA_MESSAGE("IrDA: Registered device %s\n", net->name);
    usb_set_intfdata(intf, self);

    if (self->needspatch) {
        /* Now we fetch and upload the firmware patch */
        ret = stir421x_patch_device(self);
        self->needspatch = (ret < 0);
        if (self->needspatch) {
            IRDA_ERROR("STIR421X: Couldn't upload patch\n");
            goto err_out_6;
        }

        /* replace IrDA class descriptor with what patched device is now reporting */
        irda_desc = irda_usb_find_class_desc (self->usbintf);
        if (!irda_desc) {
            ret = -ENODEV;
            goto err_out_6;
        }
        kfree(self->irda_desc);
        self->irda_desc = irda_desc;
        irda_usb_init_qos(self);
    }

    return 0;
err_out_6:
    unregister_netdev(self->netdev);
err_out_5:
    kfree(self->tx_buff);
err_out_4:
    kfree(self->speed_buff);
err_out_3:
    /* Free all urbs that we may have created */
    usb_free_urb(self->speed_urb);
err_out_2:
    usb_free_urb(self->tx_urb);
err_out_1:
    for (i = 0; i < self->max_rx_urb; i++)
        usb_free_urb(self->rx_urb[i]);
    kfree(self->rx_urb);
err_free_net:
    free_netdev(net);
err_out:
    return ret;
}

/*------------------------------------------------------------------*/
/*
 * The current irda-usb device is removed, the USB layer tell us
 * to shut it down...
 * One of the constraints is that when we exit this function,
 * we cannot use the usb_device no more. Gone. Destroyed. kfree().
 * Most other subsystem allow you to destroy the instance at a time
 * when it's convenient to you, to postpone it to a later date, but
 * not the USB subsystem.
 * So, we must make bloody sure that everything gets deactivated.
 * Jean II
 */
static void irda_usb_disconnect(struct usb_interface *intf)
{
    unsigned long flags;
    struct irda_usb_cb *self = usb_get_intfdata(intf);
    int i;

    IRDA_DEBUG(1, "%s()\n", __func__);

    usb_set_intfdata(intf, NULL);
    if (!self)
        return;

    /* Make sure that the Tx path is not executing. - Jean II */
    spin_lock_irqsave(&self->lock, flags);

    /* Oups ! We are not there any more.
     * This will stop/desactivate the Tx path. - Jean II */
    self->present = 0;

    /* Kill defered Rx URB */
    del_timer(&self->rx_defer_timer);

    /* We need to have irq enabled to unlink the URBs. That's OK,
     * at this point the Tx path is gone - Jean II */
    spin_unlock_irqrestore(&self->lock, flags);

    /* Hum... Check if networking is still active (avoid races) */
    if((self->netopen) || (self->irlap)) {
        /* Accept no more transmissions */
        /*netif_device_detach(self->netdev);*/
        netif_stop_queue(self->netdev);
        /* Stop all the receive URBs. Must be synchronous. */
        for (i = 0; i < self->max_rx_urb; i++)
            usb_kill_urb(self->rx_urb[i]);
        /* Cancel Tx and speed URB.
         * Make sure it's synchronous to avoid races. */
        usb_kill_urb(self->tx_urb);
        usb_kill_urb(self->speed_urb);
    }

    /* Cleanup the device stuff */
    irda_usb_close(self);
    /* No longer attached to USB bus */
    self->usbdev = NULL;
    self->usbintf = NULL;

    /* Clean up our urbs */
    for (i = 0; i < self->max_rx_urb; i++)
        usb_free_urb(self->rx_urb[i]);
    kfree(self->rx_urb);
    /* Clean up Tx and speed URB */
    usb_free_urb(self->tx_urb);
    usb_free_urb(self->speed_urb);

    /* Free self and network device */
    free_netdev(self->netdev);
    IRDA_DEBUG(0, "%s(), USB IrDA Disconnected\n", __func__);
}

#ifdef CONFIG_PM
/* USB suspend, so power off the transmitter/receiver */
static int irda_usb_suspend(struct usb_interface *intf, pm_message_t message)
{
    struct irda_usb_cb *self = usb_get_intfdata(intf);
    int i;

    netif_device_detach(self->netdev);

    if (self->tx_urb != NULL)
        usb_kill_urb(self->tx_urb);
    if (self->speed_urb != NULL)
        usb_kill_urb(self->speed_urb);
    for (i = 0; i < self->max_rx_urb; i++) {
        if (self->rx_urb[i] != NULL)
            usb_kill_urb(self->rx_urb[i]);
    }
    return 0;
}

/* Coming out of suspend, so reset hardware */
static int irda_usb_resume(struct usb_interface *intf)
{
    struct irda_usb_cb *self = usb_get_intfdata(intf);
    int i;

    for (i = 0; i < self->max_rx_urb; i++) {
        if (self->rx_urb[i] != NULL)
            usb_submit_urb(self->rx_urb[i], GFP_KERNEL);
    }

    netif_device_attach(self->netdev);
    return 0;
}
#endif

/*------------------------------------------------------------------*/
/*
 * USB device callbacks
 */
static struct usb_driver irda_driver = {
    .name       = "irda-usb",
    .probe      = irda_usb_probe,
    .disconnect = irda_usb_disconnect,
    .id_table   = dongles,
#ifdef CONFIG_PM
    .suspend    = irda_usb_suspend,
    .resume     = irda_usb_resume,
#endif
};

module_usb_driver(irda_driver);

/*
 * Module parameters
 */
module_param(qos_mtt_bits, int, 0);
MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
MODULE_AUTHOR("Roman Weissgaerber <[email protected]>, Dag Brattli <[email protected]>, Jean Tourrilhes <[email protected]> and Nick Fedchik <[email protected]>");
MODULE_DESCRIPTION("IrDA-USB Dongle Driver");
MODULE_LICENSE("GPL");