xref: /linux/drivers/net/wireless/broadcom/brcm80211/brcmfmac/xtlv.c (revision 8632987380765dee716d460640aa58d58d52998e)
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 
83