[efi] Implement the EFI_PXE_BASE_CODE_PROTOCOL
[ipxe.git] / src / drivers / bus / cdc.c
1 /*
2 * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 *
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
22 */
23
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25
26 #include <stddef.h>
27 #include <ipxe/usb.h>
28 #include <ipxe/cdc.h>
29
30 /** @file
31 *
32 * USB Communications Device Class (CDC)
33 *
34 */
35
36 /**
37 * Locate CDC union functional descriptor
38 *
39 * @v config Configuration descriptor
40 * @v interface Interface descriptor
41 * @ret desc Union functional descriptor, or NULL if not found
42 */
43 struct cdc_union_descriptor *
44 cdc_union_descriptor ( struct usb_configuration_descriptor *config,
45 struct usb_interface_descriptor *interface ) {
46 struct cdc_union_descriptor *desc;
47
48 for_each_interface_descriptor ( desc, config, interface ) {
49 if ( ( desc->header.type == USB_CS_INTERFACE_DESCRIPTOR ) &&
50 ( desc->subtype == CDC_SUBTYPE_UNION ) )
51 return desc;
52 }
53 return NULL;
54 }