NFC: Set MIU and RW values from CONNECT and CC LLCP frames

We use the maximum values for the LLCP Maximum Information Unit and Receive
Window Size.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 49 insertions, 3 deletions

diff --git a/net/nfc/llcp/commands.c b/net/nfc/llcp/commands.c
index 8ebd322b11eb..a02292ba25c7 100644
--- a/net/nfc/llcp/commands.c
+++ b/net/nfc/llcp/commands.c
@@ -284,6 +284,9 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
         struct nfc_llcp_local *local;
         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;
         int err;
         u16 size = 0;
 
@@ -301,6 +304,14 @@ 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_length);
+        size += miux_tlv_length;
+
+        rw = LLCP_MAX_RW;
+        rw_tlv = nfc_llcp_build_tlv(LLCP_TLV_RW, &rw, 0, &rw_tlv_length);
+        size += rw_tlv_length;
+
         pr_debug("SKB size %d SN length %zu\n", size, sock->service_name_len);
 
         skb = llcp_allocate_pdu(sock, LLCP_PDU_CONNECT, size);
@@ -313,6 +324,9 @@ int nfc_llcp_send_connect(struct nfc_llcp_sock *sock)
                 skb = llcp_add_tlv(skb, service_name_tlv,
                                         service_name_tlv_length);
 
+        skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
+        skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
+
         skb_queue_tail(&local->tx_queue, skb);
 
         return 0;
@@ -321,6 +335,8 @@ error_tlv:
         pr_err("error %d\n", err);
 
         kfree(service_name_tlv);
+        kfree(miux_tlv);
+        kfree(rw_tlv);
 
         return err;
 }
@@ -329,6 +345,11 @@ 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;
+        int err;
+        u16 size = 0;
 
         pr_debug("Sending CC\n");
 
@@ -336,13 +357,34 @@ int nfc_llcp_send_cc(struct nfc_llcp_sock *sock)
         if (local == NULL)
                 return -ENODEV;
 
-        skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, 0);
-        if (skb == NULL)
-                return -ENOMEM;
+        miux = cpu_to_be16(LLCP_MAX_MIUX);
+        miux_tlv = nfc_llcp_build_tlv(LLCP_TLV_MIUX, (u8 *)&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);
+        size += rw_tlv_length;
+
+        skb = llcp_allocate_pdu(sock, LLCP_PDU_CC, size);
+        if (skb == NULL) {
+                err = -ENOMEM;
+                goto error_tlv;
+        }
+
+        skb = llcp_add_tlv(skb, miux_tlv, miux_tlv_length);
+        skb = llcp_add_tlv(skb, rw_tlv, rw_tlv_length);
 
         skb_queue_tail(&local->tx_queue, skb);
 
         return 0;
+
+error_tlv:
+        pr_err("error %d\n", err);
+
+        kfree(miux_tlv);
+        kfree(rw_tlv);
+
+        return err;
 }
 
 int nfc_llcp_send_dm(struct nfc_llcp_local *local, u8 ssap, u8 dsap, u8 reason)
diff --git a/net/nfc/llcp/llcp.h b/net/nfc/llcp/llcp.h
index 054c64ffdaa7..70e1762d6e8d 100644
--- a/net/nfc/llcp/llcp.h
+++ b/net/nfc/llcp/llcp.h
@@ -28,6 +28,10 @@ enum llcp_state {
 #define LLCP_DEFAULT_RW  1
 #define LLCP_DEFAULT_MIU 128
 
+#define LLCP_MAX_LTO  0xff
+#define LLCP_MAX_RW   15
+#define LLCP_MAX_MIUX 0x7ff
+
 #define LLCP_WKS_NUM_SAP   16
 #define LLCP_SDP_NUM_SAP   16
 #define LLCP_LOCAL_NUM_SAP 32