ClabureDB: Classified Bug-Reports Database

   /*****************************************************************************
    *
    * Filename:      irda-usb.c
    * Version:       0.10
    * Description:   IrDA-USB Driver
    * Status:        Experimental 
    * Author:        Dag Brattli <dag@brattli.net>
    *
    *        Copyright (C) 2000, Roman Weissgaerber <weissg@vienna.at>
   *      Copyright (C) 2001, Dag Brattli <dag@brattli.net>
   *      Copyright (C) 2001, Jean Tourrilhes <jt@hpl.hp.com>
   *      Copyright (C) 2004, SigmaTel, Inc. <irquality@sigmatel.com>
   *      Copyright (C) 2005, Milan Beno <beno@pobox.sk>
   *      Copyright (C) 2006, Nick Fedchik <nick@fedchik.org.ua>
   *          
   *        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 int 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);
 static struct net_device_stats *irda_usb_net_get_stats(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 commited 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 int irda_usb_hard_xmit(struct sk_buff *skb, struct net_device *netdev)
 {
         struct irda_usb_cb *self = netdev->priv;
         struct urb *urb = self->tx_urb;
         unsigned long flags;
         s32 speed;
         s16 xbofs;
         int res, mtt;
         int        err = 1;        /* Failed */
 
         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 */
                         err = 0;        /* No error */
                         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__);
                 self->stats.tx_errors++;
                 /* Let USB recover : We will catch that in the watchdog */
                 /*netif_start_queue(netdev);*/
         } else {
                 /* Increment packet stats */
                 self->stats.tx_packets++;
                 self->stats.tx_bytes += skb->len;
                 
                 netdev->trans_start = jiffies;
         }
         spin_unlock_irqrestore(&self->lock, flags);
         
         return 0;
 
 drop:
         /* Drop silently the skb and exit */
         dev_kfree_skb(skb);
         spin_unlock_irqrestore(&self->lock, flags);
         return err;                /* Usually 1 */
 }
 
 /*------------------------------------------------------------------*/
 /*
  * 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 commited 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;
         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 */
                 self->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->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->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->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->stats.rx_bytes += len;
         self->stats.rx_packets++;
         self->netdev->last_rx = jiffies;
 
 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[11];
        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; (fw->data[i] != STIR421X_PATCH_END_OF_HDR_TAG)
                             && (i < fw->size); i++) ;
                /* here we check for the out of buffer case */
                if ((STIR421X_PATCH_END_OF_HDR_TAG == fw->data[i])
                    && (i < STIR421X_PATCH_CODE_OFFSET)) {
                        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 = (struct irda_usb_cb *) netdev->priv;
        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 = (struct irda_usb_cb *) netdev->priv;
        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 = dev->priv;
        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;
}

/*------------------------------------------------------------------*/
/*
 * Get device stats (for /proc/net/dev and ifconfig)
 */
static struct net_device_stats *irda_usb_net_get_stats(struct net_device *dev)
{
        struct irda_usb_cb *self = dev->priv;
        return &self->stats;
}

/********************* 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);
}

/*------------------------------------------------------------------*/
/*
 * 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__);

        irda_usb_init_qos(self);

        /* Override the network functions we need to use */
        netdev->hard_start_xmit = irda_usb_hard_xmit;
        netdev->tx_timeout        = irda_usb_net_timeout;
        netdev->watchdog_timeo  = 250*HZ/1000;        /* 250 ms > USB timeout */
        netdev->open            = irda_usb_net_open;
        netdev->stop            = irda_usb_net_close;
        netdev->get_stats        = irda_usb_net_get_stats;
        netdev->do_ioctl        = irda_usb_net_ioctl;

        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 = net->priv;
        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);

        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) {
                err("reset_configuration failed");
                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]);
        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__);
}

/*------------------------------------------------------------------*/
/*
 * USB device callbacks
 */
static struct usb_driver irda_driver = {
        .name                = "irda-usb",
        .probe                = irda_usb_probe,
        .disconnect        = irda_usb_disconnect,
        .id_table        = dongles,
};

/************************* MODULE CALLBACKS *************************/
/*
 * Deal with module insertion/removal
 * Mostly tell USB about our existence
 */

/*------------------------------------------------------------------*/
/*
 * Module insertion
 */
static int __init usb_irda_init(void)
{
        int        ret;

        ret = usb_register(&irda_driver);
        if (ret < 0)
                return ret;

        IRDA_MESSAGE("USB IrDA support registered\n");
        return 0;
}
module_init(usb_irda_init);

/*------------------------------------------------------------------*/
/*
 * Module removal
 */
static void __exit usb_irda_cleanup(void)
{
        /* Deregister the driver and remove all pending instances */
        usb_deregister(&irda_driver);
}
module_exit(usb_irda_cleanup);

/*------------------------------------------------------------------*/
/*
 * Module parameters
 */
module_param(qos_mtt_bits, int, 0);
MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
MODULE_AUTHOR("Roman Weissgaerber <weissg@vienna.at>, Dag Brattli <dag@brattli.net>, Jean Tourrilhes <jt@hpl.hp.com> and Nick Fedchik <nick@fedchik.org.ua>");
MODULE_DESCRIPTION("IrDA-USB Dongle Driver");
MODULE_LICENSE("GPL");