Remy Bohmer | df06344 | 2009-07-29 18:18:43 +0200 | [diff] [blame] | 1 | /* |
| 2 | * usb/gadget/config.c -- simplify building config descriptors |
| 3 | * |
| 4 | * Copyright (C) 2003 David Brownell |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | * |
| 20 | * Ported to U-boot by: Thomas Smits <ts.smits@gmail.com> and |
| 21 | * Remy Bohmer <linux@bohmer.net> |
| 22 | */ |
| 23 | |
| 24 | #include <common.h> |
| 25 | #include <asm/errno.h> |
| 26 | #include <linux/list.h> |
| 27 | #include <linux/string.h> |
| 28 | |
| 29 | #include <linux/usb/ch9.h> |
| 30 | #include <linux/usb/gadget.h> |
| 31 | |
| 32 | |
| 33 | /** |
| 34 | * usb_descriptor_fillbuf - fill buffer with descriptors |
| 35 | * @buf: Buffer to be filled |
| 36 | * @buflen: Size of buf |
| 37 | * @src: Array of descriptor pointers, terminated by null pointer. |
| 38 | * |
| 39 | * Copies descriptors into the buffer, returning the length or a |
| 40 | * negative error code if they can't all be copied. Useful when |
| 41 | * assembling descriptors for an associated set of interfaces used |
| 42 | * as part of configuring a composite device; or in other cases where |
| 43 | * sets of descriptors need to be marshaled. |
| 44 | */ |
| 45 | int |
| 46 | usb_descriptor_fillbuf(void *buf, unsigned buflen, |
| 47 | const struct usb_descriptor_header **src) |
| 48 | { |
| 49 | u8 *dest = buf; |
| 50 | |
| 51 | if (!src) |
| 52 | return -EINVAL; |
| 53 | |
| 54 | /* fill buffer from src[] until null descriptor ptr */ |
| 55 | for (; NULL != *src; src++) { |
| 56 | unsigned len = (*src)->bLength; |
| 57 | |
| 58 | if (len > buflen) |
| 59 | return -EINVAL; |
| 60 | memcpy(dest, *src, len); |
| 61 | buflen -= len; |
| 62 | dest += len; |
| 63 | } |
| 64 | return dest - (u8 *)buf; |
| 65 | } |
| 66 | |
| 67 | |
| 68 | /** |
| 69 | * usb_gadget_config_buf - builts a complete configuration descriptor |
| 70 | * @config: Header for the descriptor, including characteristics such |
| 71 | * as power requirements and number of interfaces. |
| 72 | * @desc: Null-terminated vector of pointers to the descriptors (interface, |
| 73 | * endpoint, etc) defining all functions in this device configuration. |
| 74 | * @buf: Buffer for the resulting configuration descriptor. |
| 75 | * @length: Length of buffer. If this is not big enough to hold the |
| 76 | * entire configuration descriptor, an error code will be returned. |
| 77 | * |
| 78 | * This copies descriptors into the response buffer, building a descriptor |
| 79 | * for that configuration. It returns the buffer length or a negative |
| 80 | * status code. The config.wTotalLength field is set to match the length |
| 81 | * of the result, but other descriptor fields (including power usage and |
| 82 | * interface count) must be set by the caller. |
| 83 | * |
| 84 | * Gadget drivers could use this when constructing a config descriptor |
| 85 | * in response to USB_REQ_GET_DESCRIPTOR. They will need to patch the |
| 86 | * resulting bDescriptorType value if USB_DT_OTHER_SPEED_CONFIG is needed. |
| 87 | */ |
| 88 | int usb_gadget_config_buf( |
| 89 | const struct usb_config_descriptor *config, |
| 90 | void *buf, |
| 91 | unsigned length, |
| 92 | const struct usb_descriptor_header **desc |
| 93 | ) |
| 94 | { |
| 95 | struct usb_config_descriptor *cp = buf; |
| 96 | int len; |
| 97 | |
| 98 | /* config descriptor first */ |
| 99 | if (length < USB_DT_CONFIG_SIZE || !desc) |
| 100 | return -EINVAL; |
| 101 | *cp = *config; |
| 102 | |
| 103 | /* then interface/endpoint/class/vendor/... */ |
Vitaly Kuzmichev | 49ed805 | 2010-09-13 18:37:11 +0400 | [diff] [blame] | 104 | len = usb_descriptor_fillbuf(USB_DT_CONFIG_SIZE + (u8 *)buf, |
Remy Bohmer | df06344 | 2009-07-29 18:18:43 +0200 | [diff] [blame] | 105 | length - USB_DT_CONFIG_SIZE, desc); |
| 106 | if (len < 0) |
| 107 | return len; |
| 108 | len += USB_DT_CONFIG_SIZE; |
| 109 | if (len > 0xffff) |
| 110 | return -EINVAL; |
| 111 | |
| 112 | /* patch up the config descriptor */ |
| 113 | cp->bLength = USB_DT_CONFIG_SIZE; |
| 114 | cp->bDescriptorType = USB_DT_CONFIG; |
| 115 | cp->wTotalLength = cpu_to_le16(len); |
| 116 | cp->bmAttributes |= USB_CONFIG_ATT_ONE; |
| 117 | return len; |
| 118 | } |