xref: /openbmc/linux/drivers/usb/gadget/u_os_desc.h (revision 588b48ca)
1 /*
2  * u_os_desc.h
3  *
4  * Utility definitions for "OS Descriptors" support
5  *
6  * Copyright (c) 2014 Samsung Electronics Co., Ltd.
7  *		http://www.samsung.com
8  *
9  * Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  */
15 
16 #ifndef __U_OS_DESC_H__
17 #define __U_OS_DESC_H__
18 
19 #include <asm/unaligned.h>
20 #include <linux/nls.h>
21 
22 #define USB_EXT_PROP_DW_SIZE			0
23 #define USB_EXT_PROP_DW_PROPERTY_DATA_TYPE	4
24 #define USB_EXT_PROP_W_PROPERTY_NAME_LENGTH	8
25 #define USB_EXT_PROP_B_PROPERTY_NAME		10
26 #define USB_EXT_PROP_DW_PROPERTY_DATA_LENGTH	10
27 #define USB_EXT_PROP_B_PROPERTY_DATA		14
28 
29 #define USB_EXT_PROP_RESERVED			0
30 #define USB_EXT_PROP_UNICODE			1
31 #define USB_EXT_PROP_UNICODE_ENV		2
32 #define USB_EXT_PROP_BINARY			3
33 #define USB_EXT_PROP_LE32			4
34 #define USB_EXT_PROP_BE32			5
35 #define USB_EXT_PROP_UNICODE_LINK		6
36 #define USB_EXT_PROP_UNICODE_MULTI		7
37 
38 static inline u8 *__usb_ext_prop_ptr(u8 *buf, size_t offset)
39 {
40 	return buf + offset;
41 }
42 
43 static inline u8 *usb_ext_prop_size_ptr(u8 *buf)
44 {
45 	return __usb_ext_prop_ptr(buf, USB_EXT_PROP_DW_SIZE);
46 }
47 
48 static inline u8 *usb_ext_prop_type_ptr(u8 *buf)
49 {
50 	return __usb_ext_prop_ptr(buf, USB_EXT_PROP_DW_PROPERTY_DATA_TYPE);
51 }
52 
53 static inline u8 *usb_ext_prop_name_len_ptr(u8 *buf)
54 {
55 	return __usb_ext_prop_ptr(buf, USB_EXT_PROP_W_PROPERTY_NAME_LENGTH);
56 }
57 
58 static inline u8 *usb_ext_prop_name_ptr(u8 *buf)
59 {
60 	return __usb_ext_prop_ptr(buf, USB_EXT_PROP_B_PROPERTY_NAME);
61 }
62 
63 static inline u8 *usb_ext_prop_data_len_ptr(u8 *buf, size_t off)
64 {
65 	return __usb_ext_prop_ptr(buf,
66 				  USB_EXT_PROP_DW_PROPERTY_DATA_LENGTH + off);
67 }
68 
69 static inline u8 *usb_ext_prop_data_ptr(u8 *buf, size_t off)
70 {
71 	return __usb_ext_prop_ptr(buf, USB_EXT_PROP_B_PROPERTY_DATA + off);
72 }
73 
74 static inline void usb_ext_prop_put_size(u8 *buf, int dw_size)
75 {
76 	put_unaligned_le32(dw_size, usb_ext_prop_size_ptr(buf));
77 }
78 
79 static inline void usb_ext_prop_put_type(u8 *buf, int type)
80 {
81 	put_unaligned_le32(type, usb_ext_prop_type_ptr(buf));
82 }
83 
84 static inline int usb_ext_prop_put_name(u8 *buf, const char *name, int pnl)
85 {
86 	int result;
87 
88 	put_unaligned_le16(pnl, usb_ext_prop_name_len_ptr(buf));
89 	result = utf8s_to_utf16s(name, strlen(name), UTF16_LITTLE_ENDIAN,
90 		(wchar_t *) usb_ext_prop_name_ptr(buf), pnl - 2);
91 	if (result < 0)
92 		return result;
93 
94 	put_unaligned_le16(0, &buf[USB_EXT_PROP_B_PROPERTY_NAME + pnl - 2]);
95 
96 	return pnl;
97 }
98 
99 static inline void usb_ext_prop_put_binary(u8 *buf, int pnl, const u8 *data,
100 					   int data_len)
101 {
102 	put_unaligned_le32(data_len, usb_ext_prop_data_len_ptr(buf, pnl));
103 	memcpy(usb_ext_prop_data_ptr(buf, pnl), data, data_len);
104 }
105 
106 static inline int usb_ext_prop_put_unicode(u8 *buf, int pnl, const char *string,
107 					   int data_len)
108 {
109 	int result;
110 	put_unaligned_le32(data_len, usb_ext_prop_data_len_ptr(buf, pnl));
111 	result = utf8s_to_utf16s(string, data_len >> 1, UTF16_LITTLE_ENDIAN,
112 			(wchar_t *) usb_ext_prop_data_ptr(buf, pnl),
113 			data_len - 2);
114 	if (result < 0)
115 		return result;
116 
117 	put_unaligned_le16(0,
118 		&buf[USB_EXT_PROP_B_PROPERTY_DATA + pnl + data_len - 2]);
119 
120 	return data_len;
121 }
122 
123 #endif /* __U_OS_DESC_H__ */
124