Driver imeplementation for packing the data from the Host Driver to the
Device firmware in the eXtended Type-Length-Value (XTLV) Format.

Signed-off-by: Gokul Sivakumar <gokulkumar.sivakumar@infineon.com>
---
 drivers/net/wireless/infineon/inffmac/xtlv.c | 106 +++++++++++++++++++
 drivers/net/wireless/infineon/inffmac/xtlv.h |  37 +++++++
 2 files changed, 143 insertions(+)
 create mode 100644 drivers/net/wireless/infineon/inffmac/xtlv.c
 create mode 100644 drivers/net/wireless/infineon/inffmac/xtlv.h

diff --git a/drivers/net/wireless/infineon/inffmac/xtlv.c b/drivers/net/wireless/infineon/inffmac/xtlv.c
new file mode 100644
index 000000000000..05983783d453
--- /dev/null
+++ b/drivers/net/wireless/infineon/inffmac/xtlv.c
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: ISC
+/*
+ * Copyright (c) 2019 Broadcom
+ *
+ * Copyright (c) 2025, Infineon Technologies AG, or an affiliate of Infineon Technologies AG.
+ * All rights reserved.
+ */
+
+#include <linux/unaligned.h>
+
+#include <linux/math.h>
+#include <linux/string.h>
+#include <linux/bug.h>
+
+#include "xtlv.h"
+
+static int inff_xtlv_header_size(u16 opts)
+{
+	int len = (int)offsetof(struct inff_xtlv, data);
+
+	if (opts & INFF_XTLV_OPTION_IDU8)
+		--len;
+	if (opts & INFF_XTLV_OPTION_LENU8)
+		--len;
+
+	return len;
+}
+
+int inff_xtlv_data_size(int dlen, u16 opts)
+{
+	int hsz;
+
+	hsz = inff_xtlv_header_size(opts);
+	if (opts & INFF_XTLV_OPTION_ALIGN32)
+		return roundup(dlen + hsz, 4);
+
+	return dlen + hsz;
+}
+
+void inff_xtlv_pack_header(struct inff_xtlv *xtlv, u16 id, u16 len,
+			   const u8 *data, u16 opts)
+{
+	u8 *data_buf;
+	u16 mask = INFF_XTLV_OPTION_IDU8 | INFF_XTLV_OPTION_LENU8;
+
+	if (!(opts & mask)) {
+		u8 *idp = (u8 *)xtlv;
+		u8 *lenp = idp + sizeof(xtlv->id);
+
+		put_unaligned_le16(id, idp);
+		put_unaligned_le16(len, lenp);
+		data_buf = lenp + sizeof(u16);
+	} else if ((opts & mask) == mask) { /* u8 id and u8 len */
+		u8 *idp = (u8 *)xtlv;
+		u8 *lenp = idp + 1;
+
+		*idp = (u8)id;
+		*lenp = (u8)len;
+		data_buf = lenp + sizeof(u8);
+	} else if (opts & INFF_XTLV_OPTION_IDU8) { /* u8 id, u16 len */
+		u8 *idp = (u8 *)xtlv;
+		u8 *lenp = idp + 1;
+
+		*idp = (u8)id;
+		put_unaligned_le16(len, lenp);
+		data_buf = lenp + sizeof(u16);
+	} else if (opts & INFF_XTLV_OPTION_LENU8) { /* u16 id, u8 len */
+		u8 *idp = (u8 *)xtlv;
+		u8 *lenp = idp + sizeof(u16);
+
+		put_unaligned_le16(id, idp);
+		*lenp = (u8)len;
+		data_buf = lenp + sizeof(u8);
+	} else {
+		WARN(true, "Unexpected xtlv option");
+		return;
+	}
+
+	if (opts & INFF_XTLV_OPTION_LENU8) {
+		WARN_ON(len > 0x00ff);
+		len &= 0xff;
+	}
+
+	if (data)
+		memcpy(data_buf, data, len);
+}
+
+u32 inff_pack_xtlv(u16 id, char *data, u32 len,
+		   char **buf, u16 *buflen)
+{
+	u32 iolen;
+
+	iolen = inff_xtlv_data_size(len, INFF_XTLV_OPTION_ALIGN32);
+
+	if (iolen > *buflen) {
+		WARN(true, "xtlv buffer is too short");
+		return 0;
+	}
+
+	inff_xtlv_pack_header((void *)*buf, id, len, data,
+			      INFF_XTLV_OPTION_ALIGN32);
+
+	*buf = *buf + iolen;
+	*buflen -= iolen;
+	return iolen;
+}
diff --git a/drivers/net/wireless/infineon/inffmac/xtlv.h b/drivers/net/wireless/infineon/inffmac/xtlv.h
new file mode 100644
index 000000000000..eb7564f608ed
--- /dev/null
+++ b/drivers/net/wireless/infineon/inffmac/xtlv.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: ISC */
+/*
+ * Copyright (c) 2019 Broadcom
+ *
+ * Copyright (c) 2025, Infineon Technologies AG, or an affiliate of Infineon Technologies AG.
+ * All rights reserved.
+ */
+
+#ifndef INFF_XTLV_H
+#define INFF_XTLV_H
+
+#include <linux/types.h>
+#include <linux/bits.h>
+
+/* inf type(id), length, value with w/16 bit id/len. The structure below
+ * is nominal, and is used to support variable length id and type. See
+ * xtlv options below.
+ */
+struct inff_xtlv {
+	u16 id;
+	u16 len;
+	u8 data[];
+};
+
+enum inff_xtlv_option {
+	INFF_XTLV_OPTION_ALIGN32 = BIT(0),
+	INFF_XTLV_OPTION_IDU8 = BIT(1),
+	INFF_XTLV_OPTION_LENU8 = BIT(2),
+};
+
+int inff_xtlv_data_size(int dlen, u16 opts);
+void inff_xtlv_pack_header(struct inff_xtlv *xtlv, u16 id, u16 len,
+			   const u8 *data, u16 opts);
+u32 inff_pack_xtlv(u16 id, char *data, u32 len,
+		   char **buf, u16 *buflen);
+
+#endif /* INFF_XTLV_H */
-- 
2.25.1