irda-usb.c

是关于linux2.5.1的完全源码

/*****************************************************************************
 *
 * Filename:      irda-usb.c
 * Version:       0.9b
 * Description:   IrDA-USB Driver
 * Status:        Experimental 
 * Author:        Dag Brattli <[e-mail]>
 *
 *	Copyright (C) 2000, Roman Weissgaerber <[e-mail]>
 *      Copyright (C) 2001, Dag Brattli <[e-mail]>
 *      Copyright (C) 2001, Jean Tourrilhes <[e-mail]>
 *          
 *	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 2.4.10, 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	(For Intel/Via USB controllers)
 *	o usb-ohci	(For other USB controllers)
 *
 * This driver has NOT been tested with the following drivers :
 *	o usb-ehci	(USB 2.0 controllers)
 *
 * This driver WON'T WORK with the following drivers :
 *	o uhci		(Alternate/JE driver for Intel/Via USB controllers)
 * Amongst the reasons :
 *	o uhci doesn't implement USB_ZERO_PACKET
 *	o uhci non-compliant use of urb->timeout
 * The final fix for USB_ZERO_PACKET in uhci is likely to be in 2.4.19 and
 * 2.5.8. With this fix, the driver will work properly. More on that later.
 *
 * Jean II
 */

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

#include <linux/module.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 <net/irda/irda.h>
#include <net/irda/irlap.h>
#include <net/irda/irda_device.h>
#include <net/irda/wrapper.h>

#include <net/irda/irda-usb.h>

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

static int qos_mtt_bits = 0;

/* Master instance for each hardware found */
#define NIRUSB 4		/* Max number of USB-IrDA dongles */
static struct irda_usb_cb irda_instance[NIRUSB];

/* 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 },
	/* 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 },
	{ 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 compliant
 * with the USB-IrDA specification (and actually very very different), and
 * there is no way this driver can support those devices, apart from
 * a complete rewrite...
 * Jean II
 */

MODULE_DEVICE_TABLE(usb, dongles);

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

static struct irda_class_desc *irda_usb_find_class_desc(struct usb_device *dev, unsigned int ifnum);
static void irda_usb_disconnect(struct usb_device *dev, void *ptr);
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 int 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 int irda_usb_net_init(struct net_device *dev);
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 uglyness...
 */

/*------------------------------------------------------------------*/
/*
 * 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)
{
	/* Set the negotiated 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, __FUNCTION__ "(), not changing speed yet\n");
			*header = 0;
			return;
		}

		IRDA_DEBUG(2, __FUNCTION__ "(), changing speed to %d\n", self->new_speed);
		self->speed = self->new_speed;
		self->new_speed = -1;

		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;
		}
	} else
		/* No change */
		*header = 0;
	
	/* Set the negotiated additional XBOFS */
	if (self->new_xbofs != -1) {
		IRDA_DEBUG(2, __FUNCTION__ "(), changing xbofs to %d\n", self->new_xbofs);
		self->xbofs = self->new_xbofs;
		self->new_xbofs = -1;

		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;
		}
	}
}

/*------------------------------------------------------------------*/
/*
 * 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, __FUNCTION__ "(), speed=%d, xbofs=%d\n",
		   self->new_speed, self->new_xbofs);

	/* Grab the speed URB */
	urb = self->speed_urb;
	if (urb->status != 0) {
		WARNING(__FUNCTION__ "(), URB still in use!\n");
		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);

	/* Submit the 0 length IrDA frame to trigger new speed settings */
        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 = USB_IRDA_HEADER;
	urb->transfer_flags = USB_QUEUE_BULK | USB_ASYNC_UNLINK;
	urb->timeout = MSECS_TO_JIFFIES(100);

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

/*------------------------------------------------------------------*/
/*
 * Note : this function will be called with both speed_urb and empty_urb...
 */
static void speed_bulk_callback(struct urb *urb)
{
	struct irda_usb_cb *self = urb->context;
	
	IRDA_DEBUG(2, __FUNCTION__ "()\n");

	/* We should always have a context */
	if (self == NULL) {
		WARNING(__FUNCTION__ "(), Bug : self == NULL\n");
		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, __FUNCTION__ "(), URB complete status %d, transfer_flags 0x%04X\n", 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;

	/* If it was the speed URB, allow the stack to send more packets */
	if(urb == self->speed_urb) {
		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;

	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) || (!self->present)) {
		IRDA_DEBUG(0, __FUNCTION__ "(), Device is gone...\n");
		spin_unlock_irqrestore(&self->lock, flags);
		return 1;	/* Failed */
	}

	/* 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) {
		WARNING(__FUNCTION__ "(), URB still in use!\n");
		goto drop;
	}

	/* Make sure there is room for IrDA-USB header. The actual
	 * allocation will be done lower in skb_push().
	 * Also, we don't use directly skb_cow(), because it require
	 * headroom >= 16, which force unnecessary copies - Jean II */
	if (skb_headroom(skb) < USB_IRDA_HEADER) {
		IRDA_DEBUG(0, __FUNCTION__ "(), Insuficient skb headroom.\n");
		if (skb_cow(skb, USB_IRDA_HEADER)) {
			WARNING(__FUNCTION__ "(), failed skb_cow() !!!\n");
			goto drop;
		}
	}

	/* Change setting for next frame */
	irda_usb_build_header(self, skb_push(skb, USB_IRDA_HEADER), 0);

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

        FILL_BULK_URB(urb, self->usbdev, 
		      usb_sndbulkpipe(self->usbdev, self->bulk_out_ep),
                      skb->data, IRDA_USB_MAX_MTU,
                      write_bulk_callback, skb);
	urb->transfer_buffer_length = skb->len;
	/* Note : unlink *must* be Asynchronous because of the code in 
	 * irda_usb_net_timeout() -> call in irq - Jean II */
	urb->transfer_flags = USB_QUEUE_BULK | USB_ASYNC_UNLINK;
	/* This flag (USB_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 |= USB_ZERO_PACKET;
	/* Timeout need to be shorter than NET watchdog timer */
	urb->timeout = MSECS_TO_JIFFIES(200);