irda-usb.c

h内核

		/* 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 */
		memcpy(newskb->data, skb->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, USB_IRDA_HEADER);

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

	/* Keep stats up to date */
	self->stats.rx_bytes += dataskb->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. Another time... Jean II */

	/* Submit the idle URB to replace the URB we've just received */
	irda_usb_submit(self, skb, self->idle_rx_urb);
	/* Recycle Rx URB : Now, the idle URB is the present one */
	urb->context = NULL;
	self->idle_rx_urb = 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 */
}

/********************** 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;
	char	hwname[16];
	int i;
	
	IRDA_DEBUG(1, "%s()\n", __FUNCTION__);

	ASSERT(netdev != NULL, return -1;);
	self = (struct irda_usb_cb *) netdev->priv;
	ASSERT(self != NULL, return -1;);

	/* Can only open the device if it's there */
	if(!self->present) {
		WARNING("%s(), device not present!\n", __FUNCTION__);
		return -1;
	}

	/* 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;

	/* 
	 * 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);
	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... */
			WARNING("%s(), Failed to allocate Rx skb\n", __FUNCTION__);
			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", __FUNCTION__);

	ASSERT(netdev != NULL, return -1;);
	self = (struct irda_usb_cb *) netdev->priv;
	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);

	/* Deallocate all the Rx path buffers (URBs and skb) */
	for (i = 0; i < IU_MAX_RX_URBS; i++) {
		struct urb *urb = self->rx_urb[i];
		struct sk_buff *skb = (struct sk_buff *) urb->context;
		/* Cancel the receive command */
		usb_unlink_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 */
	self->tx_urb->transfer_flags &= ~URB_ASYNC_UNLINK;
	usb_kill_urb(self->tx_urb);
	self->speed_urb->transfer_flags &= ~URB_ASYNC_UNLINK;
	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;

	ASSERT(dev != NULL, return -1;);
	self = dev->priv;
	ASSERT(self != NULL, return -1;);

	IRDA_DEBUG(2, "%s(), %s, (cmd=0x%X)\n", __FUNCTION__, 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", __FUNCTION__);
	
	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", 
		__FUNCTION__, 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", __FUNCTION__);

	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", __FUNCTION__);

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

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