drivers/firmware/google/vpd_decode.h

   1 /*
   2  * vpd_decode.h
   3  *
   4  * Google VPD decoding routines.
   5  *
   6  * Copyright 2017 Google Inc.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License v2.0 as published by
  10  * the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #ifndef __VPD_DECODE_H
  19 #define __VPD_DECODE_H
  20
  21 #include <linux/types.h>
  22
  23 enum {
  24         VPD_OK = 0,
  25         VPD_FAIL,
  26 };
  27
  28 enum {
  29         VPD_TYPE_TERMINATOR = 0,
  30         VPD_TYPE_STRING,
  31         VPD_TYPE_INFO                = 0xfe,
  32         VPD_TYPE_IMPLICIT_TERMINATOR = 0xff,
  33 };
  34
  35 /* Callback for vpd_decode_string to invoke. */
  36 typedef int vpd_decode_callback(const u8 *key, s32 key_len,
  37                                 const u8 *value, s32 value_len,
  38                                 void *arg);
  39
  40 /*
  41  * vpd_decode_string
  42  *
  43  * Given the encoded string, this function invokes callback with extracted
  44  * (key, value). The *consumed will be plused the number of bytes consumed in
  45  * this function.
  46  *
  47  * The input_buf points to the first byte of the input buffer.
  48  *
  49  * The *consumed starts from 0, which is actually the next byte to be decoded.
  50  * It can be non-zero to be used in multiple calls.
  51  *
  52  * If one entry is successfully decoded, sends it to callback and returns the
  53  * result.
  54  */
  55 int vpd_decode_string(const s32 max_len, const u8 *input_buf, s32 *consumed,
  56                       vpd_decode_callback callback, void *callback_arg);
  57
  58 #endif  /* __VPD_DECODE_H */