cdcether.c

基于S3CEB2410平台LINUX操作系统下 USB驱动源代码

                /* Too many to filter perfectly -- accept all multicasts. */
		info("%s: set too many MC filters, using allmulti", net->name);
		ether_dev->mode_flags = MODE_FLAG_ALL_MULTICAST |
			MODE_FLAG_DIRECTED |
			MODE_FLAG_BROADCAST |
			MODE_FLAG_MULTICAST;
	} else if (net->flags & IFF_ALLMULTI) {
                /* Filter in software */
		info("%s: using allmulti", net->name);
		ether_dev->mode_flags = MODE_FLAG_ALL_MULTICAST |
			MODE_FLAG_DIRECTED |
			MODE_FLAG_BROADCAST |
			MODE_FLAG_MULTICAST;
        } else {
		/* do multicast filtering in hardware */
                struct dev_mc_list *mclist;
		info("%s: set multicast filters", net->name);
		ether_dev->mode_flags = MODE_FLAG_ALL_MULTICAST |
			MODE_FLAG_DIRECTED |
			MODE_FLAG_BROADCAST |
			MODE_FLAG_MULTICAST;
		buff = kmalloc(6 * net->mc_count, in_interrupt() ? GFP_ATOMIC : GFP_KERNEL);
                for (i = 0, mclist = net->mc_list;
		     mclist && i < net->mc_count;
                     i++, mclist = mclist->next) {
			memcpy(&mclist->dmi_addr, &buff[i * 6], 6);
		}
#if 0
		usb_control_msg(ether_dev->usb,
				usb_sndctrlpipe(ether_dev->usb, 0),
				SET_ETHERNET_MULTICAST_FILTER, /* request */
				USB_TYPE_CLASS | USB_DIR_OUT | USB_RECIP_INTERFACE, /* request type */
				cpu_to_le16(net->mc_count), /* value */
				cpu_to_le16((u16)ether_dev->comm_interface), /* index */
				buff,
				(6* net->mc_count), /* size */
				HZ); /* timeout */
#endif
		kfree(buff);
	}

#if 0 
	CDC_SetEthernetPacketFilter(ether_dev);
#endif	
        // Tell the kernel to start giving frames to us again.
	netif_wake_queue(net);
}

//////////////////////////////////////////////////////////////////////////////
// Routines used to parse out the Functional Descriptors /////////////////////
//////////////////////////////////////////////////////////////////////////////

static int parse_header_functional_descriptor( int *bFunctionLength, 
                                               int bDescriptorType, 
                                               int bDescriptorSubtype,
                                               unsigned char *data,
                                               ether_dev_t *ether_dev,
                                               int *requirements )
{
	// Check to make sure we haven't seen one of these already.
	if ( (~*requirements) & REQ_HDR_FUNC_DESCR ) {
		err( "Multiple Header Functional Descriptors found." );
		return -1;
	}
	
	// Is it the right size???
	if (*bFunctionLength != 5) {
		info( "Invalid length in Header Functional Descriptor" );
		// This is a hack to get around a particular device (NO NAMES)
		// It has this function length set to the length of the
		// whole class-specific descriptor
		*bFunctionLength = 5;
	}
	
	// Nothing extremely useful here.
	// We'll keep it for posterity
	ether_dev->bcdCDC = data[0] + (data[1] << 8);
	dbg( "Found Header descriptor, CDC version %x", ether_dev->bcdCDC);

	// We've seen one of these
	*requirements &= ~REQ_HDR_FUNC_DESCR;
	
	// It's all good.
	return 0;
}

static int parse_union_functional_descriptor( int *bFunctionLength, 
                                              int bDescriptorType, 
                                              int bDescriptorSubtype,
                                              unsigned char *data,
                                              ether_dev_t *ether_dev,
                                              int *requirements )
{
	// Check to make sure we haven't seen one of these already.
	if ( (~*requirements) & REQ_UNION_FUNC_DESCR ) {
		err( "Multiple Union Functional Descriptors found." );
		return -1;
	}

	// Is it the right size?
	if (*bFunctionLength != 5) {
		// It is NOT the size we expected.
		err( "Unsupported length in Union Functional Descriptor" );
		return -1;
	}
	
	// Sanity check of sorts
	if (ether_dev->comm_interface != data[0]) {
		// This tells us that we are chasing the wrong comm
		// interface or we are crazy or something else weird.
		if (ether_dev->comm_interface == data[1]) {
			info( "Probably broken Union descriptor, fudging data interface" );
			// We'll need this in a few microseconds, 
			// so guess here, and hope for the best
			ether_dev->data_interface = data[0];
		} else {
			err( "Union Functional Descriptor is broken beyond repair" );
			return -1;
		}
	} else{ // Descriptor is OK
       		// We'll need this in a few microseconds!
		ether_dev->data_interface = data[1];
	}

	// We've seen one of these now.
	*requirements &= ~REQ_UNION_FUNC_DESCR;
	
	// Done
	return 0;
}

static int parse_ethernet_functional_descriptor( int *bFunctionLength, 
                                                 int bDescriptorType, 
                                                 int bDescriptorSubtype,
                                                 unsigned char *data,
                                                 ether_dev_t *ether_dev,
                                                 int *requirements )
{
	// Check to make sure we haven't seen one of these already.
	if ( (~*requirements) & REQ_ETH_FUNC_DESCR ) {
		err( "Multiple Ethernet Functional Descriptors found." );
		return -1;
	}
	
	// Is it the right size?
	if (*bFunctionLength != 13) {
		err( "Invalid length in Ethernet Networking Functional Descriptor" );
		return -1;
	}
	
	// Lots of goodies from this one.  They are all important.
	ether_dev->iMACAddress = data[0];
	ether_dev->bmEthernetStatistics = data[1] + (data[2] << 8) + (data[3] << 16) + (data[4] << 24);
	ether_dev->wMaxSegmentSize = data[5] + (data[6] << 8);
	ether_dev->wNumberMCFilters = (data[7] + (data[8] << 8)) & 0x00007FFF;
	if (ether_dev->wNumberMCFilters > multicast_filter_limit) {
		ether_dev->wNumberMCFilters = multicast_filter_limit;
		}	
	ether_dev->bNumberPowerFilters = data[9];
	
	// We've seen one of these now.
	*requirements &= ~REQ_ETH_FUNC_DESCR;
	
	// That's all she wrote.
	return 0;
}

static int parse_protocol_unit_functional_descriptor( int *bFunctionLength, 
                                                      int bDescriptorType, 
                                                      int bDescriptorSubtype,
                                                      unsigned char *data,
                                                      ether_dev_t *ether_dev,
                                                      int *requirements )
{
	// There should only be one type if we are sane
	if (bDescriptorType != CS_INTERFACE) {
		info( "Invalid bDescriptorType found." );
		return -1;
	}

	// The Subtype tells the tale.
	switch (bDescriptorSubtype){
		case 0x00:	// Header Functional Descriptor
			return parse_header_functional_descriptor( bFunctionLength,
			                                           bDescriptorType,
			                                           bDescriptorSubtype,
			                                           data,
			                                           ether_dev,
			                                           requirements );
			break;
		case 0x06:	// Union Functional Descriptor
			return parse_union_functional_descriptor( bFunctionLength,
			                                          bDescriptorType,
			                                          bDescriptorSubtype,
			                                          data,
			                                          ether_dev,
			                                          requirements );
			break;
		case 0x0F:	// Ethernet Networking Functional Descriptor
			return parse_ethernet_functional_descriptor( bFunctionLength,
			                                             bDescriptorType,
			                                             bDescriptorSubtype,
			                                             data,
			                                             ether_dev,
			                                             requirements );
			break;
		default:	// We don't support this at this time...
			// However that doesn't necessarily indicate an error.
			dbg( "Unexpected header type %x:", bDescriptorSubtype );
			return 0;
	}
	// How did we get here???
	return -1;
}

static int parse_ethernet_class_information( unsigned char *data, int length, ether_dev_t *ether_dev )
{
	int loc = 0;
	int rc;
	int bFunctionLength;
	int bDescriptorType;
	int bDescriptorSubtype;
	int requirements = REQUIREMENTS_TOTAL;

	// As long as there is something here, we will try to parse it
	while (loc < length) {
		// Length
		bFunctionLength = data[loc];
		loc++;
		
		// Type
		bDescriptorType = data[loc];
		loc++;
		
		// Subtype
		bDescriptorSubtype = data[loc];
		loc++;
		
		// ship this off to be processed elsewhere.
		rc = parse_protocol_unit_functional_descriptor( &bFunctionLength, 
		                                                bDescriptorType, 
		                                                bDescriptorSubtype, 
		                                                &data[loc],
		                                                ether_dev,
		                                                &requirements );
		// Did it process okay?
		if (rc)	{
			// Something was hosed somewhere.
			// No need to continue;
			err("Bad descriptor parsing: %x", rc );
			return -1;
		}
		// We have already taken three bytes.
		loc += (bFunctionLength - 3);
	}
	// Check to see if we got everything we need.
	if (requirements) {
		// We missed some of the requirements...
		err( "Not all required functional descriptors present 0x%08X", requirements );
		return -1;
	}
	// We got everything.
	return 0;
}

//////////////////////////////////////////////////////////////////////////////
// Routine to check for the existence of the Functional Descriptors //////////
//////////////////////////////////////////////////////////////////////////////

static int find_and_parse_ethernet_class_information( struct usb_device *device, ether_dev_t *ether_dev )
{
	struct usb_config_descriptor *conf = NULL;
	struct usb_interface *comm_intf_group = NULL;
	struct usb_interface_descriptor *comm_intf = NULL;
	int rc = -1;
	// The assumption here is that find_ethernet_comm_interface
	// and find_valid_configuration 
	// have already filled in the information about where to find
	// the a valid commication interface.

	conf = &( device->config[ether_dev->configuration_num] );
	comm_intf_group = &( conf->interface[ether_dev->comm_interface] );
	comm_intf = &( comm_intf_group->altsetting[ether_dev->comm_interface_altset_num] );
	// Let's check and see if it has the extra information we need...

	if (comm_intf->extralen > 0) {
		// This is where the information is SUPPOSED to be.
		rc = parse_ethernet_class_information( comm_intf->extra, comm_intf->extralen, ether_dev );
	} else if (conf->extralen > 0) {
		// This is a hack.  The spec says it should be at the interface 
		// location checked above.  However I have seen it here also.
		// This is the same device that requires the functional descriptor hack above
		warn( "Ethernet information found at device configuration.  This is broken." );
		rc = parse_ethernet_class_information( conf->extra, conf->extralen, ether_dev );
	} else 	{
		// I don't know where else to look.
		warn( "No ethernet information found." );
		rc = -1;
	}
	return rc;
}

//////////////////////////////////////////////////////////////////////////////
// Routines to verify the data interface /////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////

static int get_data_interface_endpoints( struct usb_device *device, ether_dev_t *ether_dev )
{
	struct usb_config_descriptor *conf = NULL;
	struct usb_interface *data_intf_group = NULL;
	struct usb_interface_descriptor *data_intf = NULL;
	
	// Walk through and get to the data interface we are checking.
	conf = &( device->config[ether_dev->configuration_num] );
	data_intf_group = &( conf->interface[ether_dev->data_interface] );
	data_intf = &( data_intf_group->altsetting[ether_dev->data_interface_altset_num_with_traffic] );

	// Start out assuming we won't find anything we can use
	ether_dev->data_ep_in = 0;
	ether_dev->data_ep_out = 0;
	
	// If these are not BULK endpoints, we don't want them
	if ( data_intf->endpoint[0].bmAttributes != 0x02 ) {
		return -1;
	} if ( data_intf->endpoint[1].bmAttributes != 0x02 ) {
		return -1;
	}

	// Check the first endpoint to see if it is IN or OUT
	if ( data_intf->endpoint[0].bEndpointAddress & 0x80 ) {
		// This endpoint is IN
		ether_dev->data_ep_in = data_intf->endpoint[0].bEndpointAddress & 0x7F;
	} else {
		// This endpoint is OUT
		ether_dev->data_ep_out = data_intf->endpoint[0].bEndpointAddress & 0x7F;
		ether_dev->data_ep_out_size = data_intf->endpoint[0].wMaxPacketSize;
	}

	// Check the second endpoint to see if it is IN or OUT
	if ( data_intf->endpoint[1].bEndpointAddress & 0x80 ) {
		// This endpoint is IN
		ether_dev->data_ep_in = data_intf->endpoint[1].bEndpointAddress & 0x7F;
	} else	{
		// This endpoint is OUT
		ether_dev->data_ep_out = data_intf->endpoint[1].bEndpointAddress & 0x7F;
		ether_dev->data_ep_out_size = data_intf->endpoint[1].wMaxPacketSize;
	}
	
	// Now make sure we got both an IN and an OUT
	if (ether_dev->data_ep_in && ether_dev->data_ep_out) {
		// We did get both, we are in good shape...
		info( "detected BULK OUT packets of size %d", ether_dev->data_ep_out_size );
		return 0;
	}
	return -1;
}

static int verify_ethernet_data_interface( struct usb_device *device, ether_dev_t *ether_dev )
{
	struct usb_config_descriptor *conf = NULL;
	struct usb_interface *data_intf_group = NULL;
	struct usb_interface_descriptor *data_intf = NULL;
	int rc = -1;
	int status;
	int altset_num;

	// The assumption here is that parse_ethernet_class_information()
	// and find_valid_configuration() 
	// have already filled in the information about where to find
	// a data interface
	conf = &( device->config[ether_dev->configuration_num] );
	data_intf_group = &( conf->interface[ether_dev->data_interface] );

	// start out assuming we won't find what we are looking for.
	ether_dev->data_interface_altset_num_with_traffic = -1;
	ether_dev->data_bAlternateSetting_with_traffic = -1;
	ether_dev->data_interface_altset_num_without_traffic = -1;
	ether_dev->data_bAlternateSetting_without_traffic = -1;

	// Walk through every possible setting for this interface until
	// we find what makes us happy.
	for ( altset_num = 0; altset_num < data_intf_group->num_altsetting; altset_num++ ) {
		data_intf = &( data_intf_group->altsetting[altset_num] );

		// Is this a data interface we like?
		if ( ( data_intf->bInterfaceClass == 0x0A )
		   && ( data_intf->bInterfaceSubClass == 0x00 )
		   && ( data_intf->bInterfaceProtocol == 0x00 ) ) {
			if ( data_intf->bNumEndpoints == 2 ) {
				// We are required to have one of these.
				// An interface with 2 endpoints to send Ethernet traffic back and forth
				// It actually may be possible that the device might only
				// communicate in a vendor specific manner.
				// That would not be very nice.
				// We can add that one later.
				ether_dev->data_bInterfaceNumber = data_intf->bInterfaceNumber;
				ether_dev->data_interface_altset_num_with_traffic = altset_num;
				ether_dev->data_bAlternateSetting_with_traffic = data_intf->bAlternateSetting;
				status = get_data_interface_endpoints( device, ether_dev );
				if (!status) {
					rc = 0;
				}
			}
			if ( data_intf->bNumEndpoints == 0 ) {
				// According to the spec we are SUPPOSED to have one of these
				// In fact the device is supposed to come up in this state.
				// However, I have seen a device that did not have such an interface.
				// So it must be just optional for our driver...
				ether_dev->data_bInterfaceNumber = data_intf->bInterfaceNumber;
				ether_dev->data_interface_altset_num_without_traffic = altset_num;
				ether_dev->data_bAlternateSetting_without_traffic = data_intf->bAlternateSetting;
			}
		}
	}
	return rc;
}

//////////////////////////////////////////////////////////////////////////////
// Routine to find a communication interface /////////////////////////////////
//////////////////////////////////////////////////////////////////////////////

static int find_ethernet_comm_interface( struct usb_device *device, ether_dev_t *ether_dev )
{
	struct usb_config_descriptor *conf = NULL;
	struct usb_interface *comm_intf_group = NULL;
	struct usb_interface_descriptor *comm_intf = NULL;
	int intf_num;
	int altset_num;
	int rc;

	conf = &( device->config[ether_dev->configuration_num] );

	// We need to check and see if any of these interfaces are something we want.
	// Walk through each interface one at a time
	for ( intf_num = 0; intf_num < conf->bNumInterfaces; intf_num++ ) {
		comm_intf_group = &( conf->interface[intf_num] );
		// Now for each of those interfaces, check every possible
		// alternate setting.
		for ( altset_num = 0; altset_num < comm_intf_group->num_altsetting; altset_num++ ) {
			comm_intf = &( comm_intf_group->altsetting[altset_num] );

			// Is this a communication class of interface of the
			// ethernet subclass variety.
			if ( ( comm_intf->bInterfaceClass == 0x02 )
			   && ( comm_intf->bInterfaceSubClass == 0x06 )
			   && ( comm_intf->bInterfaceProtocol == 0x00 ) ) {
				if ( comm_intf->bNumEndpoints == 1 ) {
					// Good, we found one, we will try this one