1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * vpd_decode.h
4  *
5  * Google VPD decoding routines.
6  *
7  * Copyright 2017 Google Inc.
8  */
9 
10 #ifndef __VPD_DECODE_H
11 #define __VPD_DECODE_H
12 
13 #include <linux/types.h>
14 
15 enum {
16 	VPD_OK = 0,
17 	VPD_FAIL,
18 };
19 
20 enum {
21 	VPD_TYPE_TERMINATOR = 0,
22 	VPD_TYPE_STRING,
23 	VPD_TYPE_INFO                = 0xfe,
24 	VPD_TYPE_IMPLICIT_TERMINATOR = 0xff,
25 };
26 
27 /* Callback for vpd_decode_string to invoke. */
28 typedef int vpd_decode_callback(const u8 *key, u32 key_len,
29 				const u8 *value, u32 value_len,
30 				void *arg);
31 
32 /*
33  * vpd_decode_string
34  *
35  * Given the encoded string, this function invokes callback with extracted
36  * (key, value). The *consumed will be plused the number of bytes consumed in
37  * this function.
38  *
39  * The input_buf points to the first byte of the input buffer.
40  *
41  * The *consumed starts from 0, which is actually the next byte to be decoded.
42  * It can be non-zero to be used in multiple calls.
43  *
44  * If one entry is successfully decoded, sends it to callback and returns the
45  * result.
46  */
47 int vpd_decode_string(const u32 max_len, const u8 *input_buf, u32 *consumed,
48 		      vpd_decode_callback callback, void *callback_arg);
49 
50 #endif  /* __VPD_DECODE_H */
51