drivers/net/wireless/broadcom/brcm80211/brcmfmac/xtlv.c

   1 // SPDX-License-Identifier: ISC
   2 /*
   3  * Copyright (c) 2019 Broadcom
   4  */
   5
   6 #include <asm/unaligned.h>
   7 #include <linux/string.h>
   8 #include <linux/bug.h>
   9
  10 #include "xtlv.h"
  11
  12 static int brcmf_xtlv_header_size(u16 opts)
  13 {
  14         int len = (int)offsetof(struct brcmf_xtlv, data);
  15
  16         if (opts & BRCMF_XTLV_OPTION_IDU8)
  17                 --len;
  18         if (opts & BRCMF_XTLV_OPTION_LENU8)
  19                 --len;
  20
  21         return len;
  22 }
  23
  24 int brcmf_xtlv_data_size(int dlen, u16 opts)
  25 {
  26         int hsz;
  27
  28         hsz = brcmf_xtlv_header_size(opts);
  29         if (opts & BRCMF_XTLV_OPTION_ALIGN32)
  30                 return roundup(dlen + hsz, 4);
  31
  32         return dlen + hsz;
  33 }
  34
  35 void brcmf_xtlv_pack_header(struct brcmf_xtlv *xtlv, u16 id, u16 len,
  36                             const u8 *data, u16 opts)
  37 {
  38         u8 *data_buf;
  39         u16 mask = BRCMF_XTLV_OPTION_IDU8 | BRCMF_XTLV_OPTION_LENU8;
  40
  41         if (!(opts & mask)) {
  42                 u8 *idp = (u8 *)xtlv;
  43                 u8 *lenp = idp + sizeof(xtlv->id);
  44
  45                 put_unaligned_le16(id, idp);
  46                 put_unaligned_le16(len, lenp);
  47                 data_buf = lenp + sizeof(u16);
  48         } else if ((opts & mask) == mask) { /* u8 id and u8 len */
  49                 u8 *idp = (u8 *)xtlv;
  50                 u8 *lenp = idp + 1;
  51
  52                 *idp = (u8)id;
  53                 *lenp = (u8)len;
  54                 data_buf = lenp + sizeof(u8);
  55         } else if (opts & BRCMF_XTLV_OPTION_IDU8) { /* u8 id, u16 len */
  56                 u8 *idp = (u8 *)xtlv;
  57                 u8 *lenp = idp + 1;
  58
  59                 *idp = (u8)id;
  60                 put_unaligned_le16(len, lenp);
  61                 data_buf = lenp + sizeof(u16);
  62         } else if (opts & BRCMF_XTLV_OPTION_LENU8) { /* u16 id, u8 len */
  63                 u8 *idp = (u8 *)xtlv;
  64                 u8 *lenp = idp + sizeof(u16);
  65
  66                 put_unaligned_le16(id, idp);
  67                 *lenp = (u8)len;
  68                 data_buf = lenp + sizeof(u8);
  69         } else {
  70                 WARN(true, "Unexpected xtlv option");
  71                 return;
  72         }
  73
  74         if (opts & BRCMF_XTLV_OPTION_LENU8) {
  75                 WARN_ON(len > 0x00ff);
  76                 len &= 0xff;
  77         }
  78
  79         if (data)
  80                 memcpy(data_buf, data, len);
  81 }
  82