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
   8 #include <linux/math.h>
   9 #include <linux/string.h>
  10 #include <linux/bug.h>
  11
  12 #include "xtlv.h"
  13
  14 static int brcmf_xtlv_header_size(u16 opts)
  15 {
  16         int len = (int)offsetof(struct brcmf_xtlv, data);
  17
  18         if (opts & BRCMF_XTLV_OPTION_IDU8)
  19                 --len;
  20         if (opts & BRCMF_XTLV_OPTION_LENU8)
  21                 --len;
  22
  23         return len;
  24 }
  25
  26 int brcmf_xtlv_data_size(int dlen, u16 opts)
  27 {
  28         int hsz;
  29
  30         hsz = brcmf_xtlv_header_size(opts);
  31         if (opts & BRCMF_XTLV_OPTION_ALIGN32)
  32                 return roundup(dlen + hsz, 4);
  33
  34         return dlen + hsz;
  35 }
  36
  37 void brcmf_xtlv_pack_header(struct brcmf_xtlv *xtlv, u16 id, u16 len,
  38                             const u8 *data, u16 opts)
  39 {
  40         u8 *data_buf;
  41         u16 mask = BRCMF_XTLV_OPTION_IDU8 | BRCMF_XTLV_OPTION_LENU8;
  42
  43         if (!(opts & mask)) {
  44                 u8 *idp = (u8 *)xtlv;
  45                 u8 *lenp = idp + sizeof(xtlv->id);
  46
  47                 put_unaligned_le16(id, idp);
  48                 put_unaligned_le16(len, lenp);
  49                 data_buf = lenp + sizeof(u16);
  50         } else if ((opts & mask) == mask) { /* u8 id and u8 len */
  51                 u8 *idp = (u8 *)xtlv;
  52                 u8 *lenp = idp + 1;
  53
  54                 *idp = (u8)id;
  55                 *lenp = (u8)len;
  56                 data_buf = lenp + sizeof(u8);
  57         } else if (opts & BRCMF_XTLV_OPTION_IDU8) { /* u8 id, u16 len */
  58                 u8 *idp = (u8 *)xtlv;
  59                 u8 *lenp = idp + 1;
  60
  61                 *idp = (u8)id;
  62                 put_unaligned_le16(len, lenp);
  63                 data_buf = lenp + sizeof(u16);
  64         } else if (opts & BRCMF_XTLV_OPTION_LENU8) { /* u16 id, u8 len */
  65                 u8 *idp = (u8 *)xtlv;
  66                 u8 *lenp = idp + sizeof(u16);
  67
  68                 put_unaligned_le16(id, idp);
  69                 *lenp = (u8)len;
  70                 data_buf = lenp + sizeof(u8);
  71         } else {
  72                 WARN(true, "Unexpected xtlv option");
  73                 return;
  74         }
  75
  76         if (opts & BRCMF_XTLV_OPTION_LENU8) {
  77                 WARN_ON(len > 0x00ff);
  78                 len &= 0xff;
  79         }
  80
  81         if (data)
  82                 memcpy(data_buf, data, len);
  83 }
  84