6lowpan: cleanup lowpan_header_compress

This patch changes the lowpan_header_compress function by removing
unused parameters like "len" and drop static value parameters of
protocol type. Instead we really check the protocol type inside inside
the skb structure. Also we drop the use of IEEE802154_ADDR_LEN which is
link-layer specific. Instead we using EUI64_ADDR_LEN which should always
the default case for now.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
index dd5f27d..4e4af8c 100644
--- a/net/6lowpan/iphc.c
+++ b/net/6lowpan/iphc.c
@@ -423,16 +423,15 @@
 	return rol8(val, shift);
 }
 
-int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev,
-			   unsigned short type, const void *_daddr,
-			   const void *_saddr, unsigned int len)
+int lowpan_header_compress(struct sk_buff *skb, const struct net_device *dev,
+			   const void *daddr, const void *saddr)
 {
 	u8 tmp, iphc0, iphc1, *hc_ptr;
 	struct ipv6hdr *hdr;
 	u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {};
 	int ret, addr_type;
 
-	if (type != ETH_P_IPV6)
+	if (skb->protocol != htons(ETH_P_IPV6))
 		return -EINVAL;
 
 	hdr = ipv6_hdr(skb);
@@ -456,10 +455,8 @@
 
 	/* TODO: context lookup */
 
-	raw_dump_inline(__func__, "saddr",
-			(unsigned char *)_saddr, IEEE802154_ADDR_LEN);
-	raw_dump_inline(__func__, "daddr",
-			(unsigned char *)_daddr, IEEE802154_ADDR_LEN);
+	raw_dump_inline(__func__, "saddr", saddr, EUI64_ADDR_LEN);
+	raw_dump_inline(__func__, "daddr", daddr, EUI64_ADDR_LEN);
 
 	raw_dump_table(__func__, "sending raw skb network uncompressed packet",
 		       skb->data, skb->len);
@@ -544,7 +541,7 @@
 		if (addr_type & IPV6_ADDR_LINKLOCAL) {
 			iphc1 |= lowpan_compress_addr_64(&hc_ptr,
 							 LOWPAN_IPHC_SAM_BIT,
-							 &hdr->saddr, _saddr);
+							 &hdr->saddr, saddr);
 			pr_debug("source address unicast link-local %pI6c iphc1 0x%02x\n",
 				 &hdr->saddr, iphc1);
 		} else {
@@ -589,7 +586,7 @@
 		if (addr_type & IPV6_ADDR_LINKLOCAL) {
 			/* TODO: context lookup */
 			iphc1 |= lowpan_compress_addr_64(&hc_ptr,
-				LOWPAN_IPHC_DAM_BIT, &hdr->daddr, _daddr);
+				LOWPAN_IPHC_DAM_BIT, &hdr->daddr, daddr);
 			pr_debug("dest address unicast link-local %pI6c "
 				 "iphc1 0x%02x\n", &hdr->daddr, iphc1);
 		} else {