NFC: Extend netlink interface for LTO, RW, and MIUX parameters support

NFC_CMD_LLC_GET_PARAMS: request LTO, RW, and MIUX parameters for a device

NFC_CMD_LLC_SET_PARAMS: set one or more of LTO, RW, and MIUX parameters for
a device. LTO must be set before the link is up otherwise -EINPROGRESS is
returned. RW and MIUX can be set at anytime and will be passed in subsequent
CONNECT and CC messages. If one of the passed parameters is wrong none is
set and -EINVAL is returned.

Signed-off-by: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 16 insertions, 19 deletions

diff --git a/net/nfc/llcp/commands.c b/net/nfc/llcp/commands.c
index 79415353cc2..ed2d17312d6 100644
--- a/net/nfc/llcp/commands.c
+++ b/net/nfc/llcp/commands.c
@@ -316,8 +316,7 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 	struct sk_buff *skb;
 	u8 *service_name_tlv = NULL, service_name_tlv_length;
 	u8 *miux_tlv = NULL, miux_tlv_length;
-	u8 *rw_tlv = NULL, rw_tlv_length, rw;
-	__be16 miux;
+	u8 *rw_tlv = NULL, rw_tlv_length;
 	int err;
 	u16 size = 0;
 
@@ -335,13 +334,11 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
 		size += service_name_tlv_length;
 	}
 
-	miux = cpu_to_be16(LLCP_MAX_MIUX);
-	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
+	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
 				      &miux_tlv_length);
 	size += miux_tlv_length;
 
-	rw = LLCP_MAX_RW;
-	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
+	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->rw, 0, &rw_tlv_length);
 	size += rw_tlv_length;
 
 	pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
@@ -378,8 +375,7 @@ int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 	struct nfc_llcp_local *local;
 	struct sk_buff *skb;
 	u8 *miux_tlv = NULL, miux_tlv_length;
-	u8 *rw_tlv = NULL, rw_tlv_length, rw;
-	__be16 miux;
+	u8 *rw_tlv = NULL, rw_tlv_length;
 	int err;
 	u16 size = 0;
 
@@ -389,13 +385,11 @@ int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
 	if (local == NULL)
 		return -ENODEV;
 
-	miux = cpu_to_be16(LLCP_MAX_MIUX);
-	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
+	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
 				      &miux_tlv_length);
 	size += miux_tlv_length;
 
-	rw = LLCP_MAX_RW;
-	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
+	rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &local->rw, 0, &rw_tlv_length);
 	size += rw_tlv_length;
 
 	skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
diff --git a/net/nfc/llcp/llcp.c b/net/nfc/llcp/llcp.c
index 2e23bd348eb..f6804532047 100644
--- a/net/nfc/llcp/llcp.c
+++ b/net/nfc/llcp/llcp.c
@@ -467,10 +467,9 @@ static u8 nfc_llcp_reserve_sdp_ssap(struct nfc_llcp_local *local)
 static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 {
 	u8 *gb_cur, *version_tlv, version, version_length;
-	u8 *lto_tlv, lto, lto_length;
+	u8 *lto_tlv, lto_length;
 	u8 *wks_tlv, wks_length;
 	u8 *miux_tlv, miux_length;
-	__be16 miux;
 	u8 gb_len = 0;
 	int ret = 0;
 
@@ -479,9 +478,7 @@ static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 					 1, &version_length);
 	gb_len += version_length;
 
-	/* 1500 ms */
-	lto = 150;
-	lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &lto, 1, &lto_length);
+	lto_tlv = nfc_llcp_build_tlv(LLCP_TLV_LTO, &local->lto, 1, &lto_length);
 	gb_len += lto_length;
 
 	pr_debug("Local wks 0x%lx\n", local->local_wks);
@@ -489,8 +486,7 @@ static int nfc_llcp_build_gb(struct nfc_llcp_local *local)
 				     &wks_length);
 	gb_len += wks_length;
 
-	miux = cpu_to_be16(LLCP_MAX_MIUX);
-	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&miux, 0,
+	miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&local->miux, 0,
 				      &miux_length);
 	gb_len += miux_length;
 
@@ -1383,6 +1379,10 @@ int nfc_llcp_register_device(struct nfc_dev *ndev)
 	rwlock_init(&local->connecting_sockets.lock);
 	rwlock_init(&local->raw_sockets.lock);
 
+	local->lto = 150; /* 1500 ms */
+	local->rw = LLCP_MAX_RW;
+	local->miux = cpu_to_be16(LLCP_MAX_MIUX);
+
 	nfc_llcp_build_gb(local);
 
 	local->remote_miu = LLCP_DEFAULT_MIU;
diff --git a/net/nfc/llcp/llcp.h b/net/nfc/llcp/llcp.h
index 276da3a6a58..0d62366f8cc 100644
--- a/net/nfc/llcp/llcp.h
+++ b/net/nfc/llcp/llcp.h
@@ -64,6 +64,9 @@ struct nfc_llcp_local {
 	u32 target_idx;
 	u8 rf_mode;
 	u8 comm_mode;
+	u8 lto;
+	u8 rw;
+	__be16 miux;
 	unsigned long local_wks;      /* Well known services */
 	unsigned long local_sdp;      /* Local services  */
 	unsigned long local_sap; /* Local SAPs, not available for discovery */