diff --git a/include/linux/caif/caif_socket.h b/include/linux/caif/caif_socket.h
index 8e5c8444a3f4c1a50e577c303b4595375663f477..2a61eb1beb85318bcd1972014a52fd8e3dff6519 100644
--- a/include/linux/caif/caif_socket.h
+++ b/include/linux/caif/caif_socket.h
@@ -16,7 +16,6 @@
 #include <sys/socket.h>
 #endif
 
-
 /**
  * enum caif_link_selector -    Physical Link Selection.
  * @CAIF_LINK_HIGH_BANDW:	Physical interface for high-bandwidth
@@ -59,7 +58,7 @@ enum caif_channel_priority {
 /**
  * enum caif_protocol_type  -	CAIF Channel type.
  * @CAIFPROTO_AT:		Classic AT channel.
- * @CAIFPROTO_DATAGRAM:		Datagram channel.
+ * @CAIFPROTO_DATAGRAM:	Datagram channel.
  * @CAIFPROTO_DATAGRAM_LOOP:	Datagram loopback channel, used for testing.
  * @CAIFPROTO_UTIL:		Utility (Psock) channel.
  * @CAIFPROTO_RFM:		Remote File Manager
@@ -87,6 +86,7 @@ enum caif_at_type {
 
 /**
  * struct sockaddr_caif - the sockaddr structure for CAIF sockets.
+ * @family:		     Address family number, must be AF_CAIF.
  * @u:			     Union of address data 'switched' by family.
  * :
  * @u.at:                    Applies when family = CAIFPROTO_AT.
@@ -153,6 +153,7 @@ struct sockaddr_caif {
  *
  *
  * This enum defines the CAIF Socket options to be used on a socket
+ * of type PF_CAIF.
  *
  */
 enum caif_socket_opts {
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
index d455375789fbc0bfc55af25c748880b17c48ec4f..c3a70c5c893a8efe0603b5e4a82a4e4ae515b10f 100644
--- a/net/caif/caif_socket.c
+++ b/net/caif/caif_socket.c
@@ -1,7 +1,6 @@
 /*
  * Copyright (C) ST-Ericsson AB 2010
  * Author:	Sjur Brendeland sjur.brandeland@stericsson.com
- *		Per Sigmond per.sigmond@stericsson.com
  * License terms: GNU General Public License (GPL) version 2
  */
 
@@ -16,91 +15,52 @@
 #include <linux/poll.h>
 #include <linux/tcp.h>
 #include <linux/uaccess.h>
-#include <asm/atomic.h>
-
+#include <linux/mutex.h>
+#include <linux/debugfs.h>
 #include <linux/caif/caif_socket.h>
+#include <asm/atomic.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
 #include <net/caif/caif_layer.h>
 #include <net/caif/caif_dev.h>
 #include <net/caif/cfpkt.h>
 
 MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(AF_CAIF);
+
+#define CAIF_DEF_SNDBUF (CAIF_MAX_PAYLOAD_SIZE*10)
+#define CAIF_DEF_RCVBUF (CAIF_MAX_PAYLOAD_SIZE*100)
+
+/*
+ * CAIF state is re-using the TCP socket states.
+ * caif_states stored in sk_state reflect the state as reported by
+ * the CAIF stack, while sk_socket->state is the state of the socket.
+ */
+enum caif_states {
+	CAIF_CONNECTED		= TCP_ESTABLISHED,
+	CAIF_CONNECTING	= TCP_SYN_SENT,
+	CAIF_DISCONNECTED	= TCP_CLOSE
+};
+
+#define TX_FLOW_ON_BIT	1
+#define RX_FLOW_ON_BIT	2
 
-#define CHNL_SKT_READ_QUEUE_HIGH 200
-#define CHNL_SKT_READ_QUEUE_LOW 100
-
-static int caif_sockbuf_size = 40000;
-static atomic_t caif_nr_socks = ATOMIC_INIT(0);
-
-#define CONN_STATE_OPEN_BIT	      1
-#define CONN_STATE_PENDING_BIT	      2
-#define CONN_STATE_PEND_DESTROY_BIT   3
-#define CONN_REMOTE_SHUTDOWN_BIT      4
-
-#define TX_FLOW_ON_BIT		      1
-#define RX_FLOW_ON_BIT		      2
-
-#define STATE_IS_OPEN(cf_sk) test_bit(CONN_STATE_OPEN_BIT,\
-				    (void *) &(cf_sk)->conn_state)
-#define STATE_IS_REMOTE_SHUTDOWN(cf_sk) test_bit(CONN_REMOTE_SHUTDOWN_BIT,\
-				    (void *) &(cf_sk)->conn_state)
-#define STATE_IS_PENDING(cf_sk) test_bit(CONN_STATE_PENDING_BIT,\
-				       (void *) &(cf_sk)->conn_state)
-#define STATE_IS_PENDING_DESTROY(cf_sk) test_bit(CONN_STATE_PEND_DESTROY_BIT,\
-				       (void *) &(cf_sk)->conn_state)
-
-#define SET_STATE_PENDING_DESTROY(cf_sk) set_bit(CONN_STATE_PEND_DESTROY_BIT,\
-				    (void *) &(cf_sk)->conn_state)
-#define SET_STATE_OPEN(cf_sk) set_bit(CONN_STATE_OPEN_BIT,\
-				    (void *) &(cf_sk)->conn_state)
-#define SET_STATE_CLOSED(cf_sk) clear_bit(CONN_STATE_OPEN_BIT,\
-					(void *) &(cf_sk)->conn_state)
-#define SET_PENDING_ON(cf_sk) set_bit(CONN_STATE_PENDING_BIT,\
-				    (void *) &(cf_sk)->conn_state)
-#define SET_PENDING_OFF(cf_sk) clear_bit(CONN_STATE_PENDING_BIT,\
-				       (void *) &(cf_sk)->conn_state)
-#define SET_REMOTE_SHUTDOWN(cf_sk) set_bit(CONN_REMOTE_SHUTDOWN_BIT,\
-				    (void *) &(cf_sk)->conn_state)
-
-#define SET_REMOTE_SHUTDOWN_OFF(dev) clear_bit(CONN_REMOTE_SHUTDOWN_BIT,\
-				    (void *) &(dev)->conn_state)
-#define RX_FLOW_IS_ON(cf_sk) test_bit(RX_FLOW_ON_BIT,\
-				    (void *) &(cf_sk)->flow_state)
-#define TX_FLOW_IS_ON(cf_sk) test_bit(TX_FLOW_ON_BIT,\
-				    (void *) &(cf_sk)->flow_state)
-
-#define SET_RX_FLOW_OFF(cf_sk) clear_bit(RX_FLOW_ON_BIT,\
-				       (void *) &(cf_sk)->flow_state)
-#define SET_RX_FLOW_ON(cf_sk) set_bit(RX_FLOW_ON_BIT,\
-				    (void *) &(cf_sk)->flow_state)
-#define SET_TX_FLOW_OFF(cf_sk) clear_bit(TX_FLOW_ON_BIT,\
-				       (void *) &(cf_sk)->flow_state)
-#define SET_TX_FLOW_ON(cf_sk) set_bit(TX_FLOW_ON_BIT,\
-				    (void *) &(cf_sk)->flow_state)
-
-#define SKT_READ_FLAG 0x01
-#define SKT_WRITE_FLAG 0x02
 static struct dentry *debugfsdir;
-#include <linux/debugfs.h>
 
 #ifdef CONFIG_DEBUG_FS
 struct debug_fs_counter {
-	atomic_t num_open;
-	atomic_t num_close;
-	atomic_t num_init;
-	atomic_t num_init_resp;
-	atomic_t num_init_fail_resp;
-	atomic_t num_deinit;
-	atomic_t num_deinit_resp;
+	atomic_t caif_nr_socks;
+	atomic_t num_connect_req;
+	atomic_t num_connect_resp;
+	atomic_t num_connect_fail_resp;
+	atomic_t num_disconnect;
 	atomic_t num_remote_shutdown_ind;
 	atomic_t num_tx_flow_off_ind;
 	atomic_t num_tx_flow_on_ind;
 	atomic_t num_rx_flow_off;
 	atomic_t num_rx_flow_on;
-	atomic_t skb_in_use;
-	atomic_t skb_alloc;
-	atomic_t skb_free;
 };
-static struct debug_fs_counter cnt;
+struct debug_fs_counter cnt;
 #define	dbfs_atomic_inc(v) atomic_inc(v)
 #define	dbfs_atomic_dec(v) atomic_dec(v)
 #else
@@ -108,624 +68,666 @@ static struct debug_fs_counter cnt;
 #define	dbfs_atomic_dec(v)
 #endif
 
-/* The AF_CAIF socket */
 struct caifsock {
-	/* NOTE: sk has to be the first member */
-	struct sock sk;
+	struct sock sk; /* must be first member */
 	struct cflayer layer;
-	char name[CAIF_LAYER_NAME_SZ];
-	u32 conn_state;
+	char name[CAIF_LAYER_NAME_SZ]; /* Used for debugging */
 	u32 flow_state;
-	struct cfpktq *pktq;
-	int file_mode;
 	struct caif_connect_request conn_req;
-	int read_queue_len;
-	/* protect updates of read_queue_len */
-	spinlock_t read_queue_len_lock;
+	struct mutex readlock;
 	struct dentry *debugfs_socket_dir;
 };
 
-static void drain_queue(struct caifsock *cf_sk);
+static int rx_flow_is_on(struct caifsock *cf_sk)
+{
+	return test_bit(RX_FLOW_ON_BIT,
+			(void *) &cf_sk->flow_state);
+}
+
+static int tx_flow_is_on(struct caifsock *cf_sk)
+{
+	return test_bit(TX_FLOW_ON_BIT,
+			(void *) &cf_sk->flow_state);
+}
 
-/* Packet Receive Callback function called from CAIF Stack */
-static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
+static void set_rx_flow_off(struct caifsock *cf_sk)
 {
-	struct caifsock *cf_sk;
-	int read_queue_high;
-	cf_sk = container_of(layr, struct caifsock, layer);
+	 clear_bit(RX_FLOW_ON_BIT,
+		 (void *) &cf_sk->flow_state);
+}
 
-	if (!STATE_IS_OPEN(cf_sk)) {
-		/*FIXME: This should be allowed finally!*/
-		pr_debug("CAIF: %s(): called after close request\n", __func__);
-		cfpkt_destroy(pkt);
-		return 0;
-	}
-	/* NOTE: This function may be called in Tasklet context! */
+static void set_rx_flow_on(struct caifsock *cf_sk)
+{
+	 set_bit(RX_FLOW_ON_BIT,
+			(void *) &cf_sk->flow_state);
+}
 
-	/* The queue has its own lock */
-	cfpkt_queue(cf_sk->pktq, pkt, 0);
+static void set_tx_flow_off(struct caifsock *cf_sk)
+{
+	 clear_bit(TX_FLOW_ON_BIT,
+		(void *) &cf_sk->flow_state);
+}
 
-	spin_lock(&cf_sk->read_queue_len_lock);
-	cf_sk->read_queue_len++;
+static void set_tx_flow_on(struct caifsock *cf_sk)
+{
+	 set_bit(TX_FLOW_ON_BIT,
+		(void *) &cf_sk->flow_state);
+}
 
-	read_queue_high = (cf_sk->read_queue_len > CHNL_SKT_READ_QUEUE_HIGH);
-	spin_unlock(&cf_sk->read_queue_len_lock);
+static void caif_read_lock(struct sock *sk)
+{
+	struct caifsock *cf_sk;
+	cf_sk = container_of(sk, struct caifsock, sk);
+	mutex_lock(&cf_sk->readlock);
+}
 
-	if (RX_FLOW_IS_ON(cf_sk) && read_queue_high) {
-		dbfs_atomic_inc(&cnt.num_rx_flow_off);
-		SET_RX_FLOW_OFF(cf_sk);
+static void caif_read_unlock(struct sock *sk)
+{
+	struct caifsock *cf_sk;
+	cf_sk = container_of(sk, struct caifsock, sk);
+	mutex_unlock(&cf_sk->readlock);
+}
 
-		/* Send flow off (NOTE: must not sleep) */
-		pr_debug("CAIF: %s():"
-			" sending flow OFF (queue len = %d)\n",
-			__func__,
-		     cf_sk->read_queue_len);
-		caif_assert(cf_sk->layer.dn);
-		caif_assert(cf_sk->layer.dn->ctrlcmd);
+int sk_rcvbuf_lowwater(struct caifsock *cf_sk)
+{
+	/* A quarter of full buffer is used a low water mark */
+	return cf_sk->sk.sk_rcvbuf / 4;
+}
 
-		(void) cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
-					       CAIF_MODEMCMD_FLOW_OFF_REQ);
-	}
+void caif_flow_ctrl(struct sock *sk, int mode)
+{
+	struct caifsock *cf_sk;
+	cf_sk = container_of(sk, struct caifsock, sk);
+	if (cf_sk->layer.dn)
+		cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, mode);
+}
 
-	/* Signal reader that data is available. */
+/*
+ * Copied from sock.c:sock_queue_rcv_skb(), but changed so packets are
+ * not dropped, but CAIF is sending flow off instead.
+ */
+int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+	int err;
+	int skb_len;
+	unsigned long flags;
+	struct sk_buff_head *list = &sk->sk_receive_queue;
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 
-	wake_up_interruptible(sk_sleep(&cf_sk->sk));
+	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
+		(unsigned)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) {
+		trace_printk("CAIF: %s():"
+			" sending flow OFF (queue len = %d %d)\n",
+			__func__,
+			atomic_read(&cf_sk->sk.sk_rmem_alloc),
+			sk_rcvbuf_lowwater(cf_sk));
+		set_rx_flow_off(cf_sk);
+		if (cf_sk->layer.dn)
+			cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
+						CAIF_MODEMCMD_FLOW_OFF_REQ);
+	}
 
+	err = sk_filter(sk, skb);
+	if (err)
+		return err;
+	if (!sk_rmem_schedule(sk, skb->truesize) && rx_flow_is_on(cf_sk)) {
+		set_rx_flow_off(cf_sk);
+		trace_printk("CAIF: %s():"
+			" sending flow OFF due to rmem_schedule\n",
+			__func__);
+		if (cf_sk->layer.dn)
+			cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
+						CAIF_MODEMCMD_FLOW_OFF_REQ);
+	}
+	skb->dev = NULL;
+	skb_set_owner_r(skb, sk);
+	/* Cache the SKB length before we tack it onto the receive
+	 * queue. Once it is added it no longer belongs to us and
+	 * may be freed by other threads of control pulling packets
+	 * from the queue.
+	 */
+	skb_len = skb->len;
+	spin_lock_irqsave(&list->lock, flags);
+	if (!sock_flag(sk, SOCK_DEAD))
+		__skb_queue_tail(list, skb);
+	spin_unlock_irqrestore(&list->lock, flags);
+
+	if (!sock_flag(sk, SOCK_DEAD))
+		sk->sk_data_ready(sk, skb_len);
+	else
+		kfree_skb(skb);
 	return 0;
 }
 
-/* Packet Flow Control Callback function called from CAIF */
-static void caif_sktflowctrl_cb(struct cflayer *layr,
-				enum caif_ctrlcmd flow,
-				int phyid)
+/* Packet Receive Callback function called from CAIF Stack */
+static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
 {
 	struct caifsock *cf_sk;
-
-	/* NOTE: This function may be called in Tasklet context! */
-	pr_debug("CAIF: %s(): flowctrl func called: %s.\n",
-		      __func__,
-		      flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" :
-		      flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" :
-		      flow == CAIF_CTRLCMD_INIT_RSP ? "INIT_RSP" :
-		      flow == CAIF_CTRLCMD_DEINIT_RSP ? "DEINIT_RSP" :
-		      flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "INIT_FAIL_RSP" :
-		      flow ==
-		      CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ? "REMOTE_SHUTDOWN" :
-		      "UKNOWN CTRL COMMAND");
-
-	if (layr == NULL)
-		return;
+	struct sk_buff *skb;
 
 	cf_sk = container_of(layr, struct caifsock, layer);
+	skb = cfpkt_tonative(pkt);
+
+	if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
+		cfpkt_destroy(pkt);
+		return 0;
+	}
+	caif_queue_rcv_skb(&cf_sk->sk, skb);
+	return 0;
+}
 
+/* Packet Control Callback function called from CAIF */
+static void caif_ctrl_cb(struct cflayer *layr,
+				enum caif_ctrlcmd flow,
+				int phyid)
+{
+	struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
 	switch (flow) {
 	case CAIF_CTRLCMD_FLOW_ON_IND:
+		/* OK from modem to start sending again */
 		dbfs_atomic_inc(&cnt.num_tx_flow_on_ind);
-		/* Signal reader that data is available. */
-		SET_TX_FLOW_ON(cf_sk);
-		wake_up_interruptible(sk_sleep(&cf_sk->sk));
+		set_tx_flow_on(cf_sk);
+		cf_sk->sk.sk_state_change(&cf_sk->sk);
 		break;
 
 	case CAIF_CTRLCMD_FLOW_OFF_IND:
+		/* Modem asks us to shut up */
 		dbfs_atomic_inc(&cnt.num_tx_flow_off_ind);
-		SET_TX_FLOW_OFF(cf_sk);
+		set_tx_flow_off(cf_sk);
+		cf_sk->sk.sk_state_change(&cf_sk->sk);
 		break;
 
 	case CAIF_CTRLCMD_INIT_RSP:
-		dbfs_atomic_inc(&cnt.num_init_resp);
-		/* Signal reader that data is available. */
-		caif_assert(STATE_IS_OPEN(cf_sk));
-		SET_PENDING_OFF(cf_sk);
-		SET_TX_FLOW_ON(cf_sk);
-		wake_up_interruptible(sk_sleep(&cf_sk->sk));
+		/* We're now connected */
+		dbfs_atomic_inc(&cnt.num_connect_resp);
+		cf_sk->sk.sk_state = CAIF_CONNECTED;
+		set_tx_flow_on(cf_sk);
+		cf_sk->sk.sk_state_change(&cf_sk->sk);
 		break;
 
 	case CAIF_CTRLCMD_DEINIT_RSP:
-		dbfs_atomic_inc(&cnt.num_deinit_resp);
-		caif_assert(!STATE_IS_OPEN(cf_sk));
-		SET_PENDING_OFF(cf_sk);
-		if (!STATE_IS_PENDING_DESTROY(cf_sk)) {
-			if (sk_sleep(&cf_sk->sk) != NULL)
-				wake_up_interruptible(sk_sleep(&cf_sk->sk));
-		}
-		dbfs_atomic_inc(&cnt.num_deinit);
-		sock_put(&cf_sk->sk);
+		/* We're now disconnected */
+		cf_sk->sk.sk_state = CAIF_DISCONNECTED;
+		cf_sk->sk.sk_state_change(&cf_sk->sk);
+		cfcnfg_release_adap_layer(&cf_sk->layer);
 		break;
 
 	case CAIF_CTRLCMD_INIT_FAIL_RSP:
-		dbfs_atomic_inc(&cnt.num_init_fail_resp);
-		caif_assert(STATE_IS_OPEN(cf_sk));
-		SET_STATE_CLOSED(cf_sk);
-		SET_PENDING_OFF(cf_sk);
-		SET_TX_FLOW_OFF(cf_sk);
-		wake_up_interruptible(sk_sleep(&cf_sk->sk));
+		/* Connect request failed */
+		dbfs_atomic_inc(&cnt.num_connect_fail_resp);
+		cf_sk->sk.sk_err = ECONNREFUSED;
+		cf_sk->sk.sk_state = CAIF_DISCONNECTED;
+		cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
+		/*
+		 * Socket "standards" seems to require POLLOUT to
+		 * be set at connect failure.
+		 */
+		set_tx_flow_on(cf_sk);
+		cf_sk->sk.sk_state_change(&cf_sk->sk);
 		break;
 
 	case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
+		/* Modem has closed this connection, or device is down. */
 		dbfs_atomic_inc(&cnt.num_remote_shutdown_ind);
-		SET_REMOTE_SHUTDOWN(cf_sk);
-		/* Use sk_shutdown to indicate remote shutdown indication */
-		cf_sk->sk.sk_shutdown |= RCV_SHUTDOWN;
-		cf_sk->file_mode = 0;
-		wake_up_interruptible(sk_sleep(&cf_sk->sk));
+		cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
+		cf_sk->sk.sk_err = ECONNRESET;
+		set_rx_flow_on(cf_sk);
+		cf_sk->sk.sk_error_report(&cf_sk->sk);
 		break;
 
 	default:
 		pr_debug("CAIF: %s(): Unexpected flow command %d\n",
-			      __func__, flow);
+				__func__, flow);
 	}
 }
 
-static void skb_destructor(struct sk_buff *skb)
+static void caif_check_flow_release(struct sock *sk)
 {
-	dbfs_atomic_inc(&cnt.skb_free);
-	dbfs_atomic_dec(&cnt.skb_in_use);
-}
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 
+	if (cf_sk->layer.dn == NULL || cf_sk->layer.dn->modemcmd == NULL)
+		return;
+	if (rx_flow_is_on(cf_sk))
+		return;
 
-static int caif_recvmsg(struct kiocb *iocb, struct socket *sock,
+	if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
+			dbfs_atomic_inc(&cnt.num_rx_flow_on);
+			set_rx_flow_on(cf_sk);
+			cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
+						CAIF_MODEMCMD_FLOW_ON_REQ);
+	}
+}
+/*
+ * Copied from sock.c:sock_queue_rcv_skb(), and added check that user buffer
+ * has sufficient size.
+ */
+
+static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
 				struct msghdr *m, size_t buf_len, int flags)
 
 {
 	struct sock *sk = sock->sk;
-	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
-	struct cfpkt *pkt = NULL;
-	size_t len;
-	int result;
 	struct sk_buff *skb;
-	ssize_t ret = -EIO;
-	int read_queue_low;
-
-	if (cf_sk == NULL) {
-		pr_debug("CAIF: %s(): private_data not set!\n",
-			      __func__);
-		ret = -EBADFD;
-		goto read_error;
-	}
-
-	/* Don't do multiple iovec entries yet */
-	if (m->msg_iovlen != 1)
-		return -EOPNOTSUPP;
+	int ret = 0;
+	int len;
 
 	if (unlikely(!buf_len))
 		return -EINVAL;
 
-	lock_sock(&(cf_sk->sk));
-
-	caif_assert(cf_sk->pktq);
-
-	if (!STATE_IS_OPEN(cf_sk)) {
-		/* Socket is closed or closing. */
-		if (!STATE_IS_PENDING(cf_sk)) {
-			pr_debug("CAIF: %s(): socket is closed (by remote)\n",
-				 __func__);
-			ret = -EPIPE;
-		} else {
-			pr_debug("CAIF: %s(): socket is closing..\n", __func__);
-			ret = -EBADF;
-		}
+	skb = skb_recv_datagram(sk, flags, 0 , &ret);
+	if (!skb)
 		goto read_error;
-	}
-	/* Socket is open or opening. */
-	if (STATE_IS_PENDING(cf_sk)) {
-		pr_debug("CAIF: %s(): socket is opening...\n", __func__);
-
-		if (flags & MSG_DONTWAIT) {
-			/* We can't block. */
-			pr_debug("CAIF: %s():state pending and MSG_DONTWAIT\n",
-				 __func__);
-			ret = -EAGAIN;
-			goto read_error;
-		}
 
+	len = skb->len;
+
+	if (skb && skb->len > buf_len && !(flags & MSG_PEEK)) {
+		len = buf_len;
 		/*
-		 * Blocking mode; state is pending and we need to wait
-		 * for its conclusion.
+		 * Push skb back on receive queue if buffer too small.
+		 * This has a built-in race where multi-threaded receive
+		 * may get packet in wrong order, but multiple read does
+		 * not really guarantee ordered delivery anyway.
+		 * Let's optimize for speed without taking locks.
 		 */
-		release_sock(&cf_sk->sk);
-
-		result =
-		    wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-					     !STATE_IS_PENDING(cf_sk));
 
-		lock_sock(&(cf_sk->sk));
-
-		if (result == -ERESTARTSYS) {
-			pr_debug("CAIF: %s(): wait_event_interruptible"
-				 " woken by a signal (1)", __func__);
-			ret = -ERESTARTSYS;
-			goto read_error;
-		}
+		skb_queue_head(&sk->sk_receive_queue, skb);
+		ret = -EMSGSIZE;
+		goto read_error;
 	}
 
-	if (STATE_IS_REMOTE_SHUTDOWN(cf_sk) ||
-		!STATE_IS_OPEN(cf_sk) ||
-		STATE_IS_PENDING(cf_sk)) {
-
-		pr_debug("CAIF: %s(): socket closed\n",
-			__func__);
-		ret = -ESHUTDOWN;
+	ret = skb_copy_datagram_iovec(skb, 0, m->msg_iov, len);
+	if (ret)
 		goto read_error;
-	}
 
-	/*
-	 * Block if we don't have any received buffers.
-	 * The queue has its own lock.
-	 */
-	while ((pkt = cfpkt_qpeek(cf_sk->pktq)) == NULL) {
+	skb_free_datagram(sk, skb);
 
-		if (flags & MSG_DONTWAIT) {
-			pr_debug("CAIF: %s(): MSG_DONTWAIT\n", __func__);
-			ret = -EAGAIN;
-			goto read_error;
-		}
-		trace_printk("CAIF: %s() wait_event\n", __func__);
+	caif_check_flow_release(sk);
 
-		/* Let writers in. */
-		release_sock(&cf_sk->sk);
+	return len;
 
-		/* Block reader until data arrives or socket is closed. */
-		if (wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-					cfpkt_qpeek(cf_sk->pktq)
-					|| STATE_IS_REMOTE_SHUTDOWN(cf_sk)
-					|| !STATE_IS_OPEN(cf_sk)) ==
-		    -ERESTARTSYS) {
-			pr_debug("CAIF: %s():"
-				" wait_event_interruptible woken by "
-				"a signal, signal_pending(current) = %d\n",
-				__func__,
-				signal_pending(current));
-			return -ERESTARTSYS;
-		}
+read_error:
+	return ret;
+}
 
-		trace_printk("CAIF: %s() awake\n", __func__);
-		if (STATE_IS_REMOTE_SHUTDOWN(cf_sk)) {
-			pr_debug("CAIF: %s(): "
-				 "received remote_shutdown indication\n",
-				 __func__);
-			ret = -ESHUTDOWN;
-			goto read_error_no_unlock;
-		}
 
-		/* I want to be alone on cf_sk (except status and queue). */
-		lock_sock(&(cf_sk->sk));
+/* Copied from unix_stream_wait_data, identical except for lock call. */
+static long caif_stream_data_wait(struct sock *sk, long timeo)
+{
+	DEFINE_WAIT(wait);
+	lock_sock(sk);
+
+	for (;;) {
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+
+		if (!skb_queue_empty(&sk->sk_receive_queue) ||
+			sk->sk_err ||
+			sk->sk_state != CAIF_CONNECTED ||
+			sock_flag(sk, SOCK_DEAD) ||
+			(sk->sk_shutdown & RCV_SHUTDOWN) ||
+			signal_pending(current) ||
+			!timeo)
+			break;
 
-		if (!STATE_IS_OPEN(cf_sk)) {
-			/* Someone closed the link, report error. */
-			pr_debug("CAIF: %s(): remote end shutdown!\n",
-				      __func__);
-			ret = -EPIPE;
-			goto read_error;
-		}
+		set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+		release_sock(sk);
+		timeo = schedule_timeout(timeo);
+		lock_sock(sk);
+		clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
 	}
 
-	/* The queue has its own lock. */
-	len = cfpkt_getlen(pkt);
-
-	/* Check max length that can be copied. */
-	if (len <= buf_len)
-		pkt = cfpkt_dequeue(cf_sk->pktq);
-	else {
-		pr_debug("CAIF: %s(): user buffer too small (%ld,%ld)\n",
-			 __func__, (long) len, (long) buf_len);
-		if (sock->type == SOCK_SEQPACKET) {
-			ret = -EMSGSIZE;
-			goto read_error;
-		}
-		len = buf_len;
-	}
+	finish_wait(sk_sleep(sk), &wait);
+	release_sock(sk);
+	return timeo;
+}
 
 
-	spin_lock(&cf_sk->read_queue_len_lock);
-	cf_sk->read_queue_len--;
-	read_queue_low = (cf_sk->read_queue_len < CHNL_SKT_READ_QUEUE_LOW);
-	spin_unlock(&cf_sk->read_queue_len_lock);
+/*
+ * Copied from unix_stream_recvmsg, but removed credit checks,
+ * changed locking calls, changed address handling.
+ */
+static int caif_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
+				struct msghdr *msg, size_t size,
+				int flags)
+{
+	struct sock *sk = sock->sk;
+	int copied = 0;
+	int target;
+	int err = 0;
+	long timeo;
 
-	if (!RX_FLOW_IS_ON(cf_sk) && read_queue_low) {
-		dbfs_atomic_inc(&cnt.num_rx_flow_on);
-		SET_RX_FLOW_ON(cf_sk);
+	err = -EOPNOTSUPP;
+	if (flags&MSG_OOB)
+		goto out;
 
-		/* Send flow on. */
-		pr_debug("CAIF: %s(): sending flow ON (queue len = %d)\n",
-			 __func__, cf_sk->read_queue_len);
-		caif_assert(cf_sk->layer.dn);
-		caif_assert(cf_sk->layer.dn->ctrlcmd);
-		(void) cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
-					       CAIF_MODEMCMD_FLOW_ON_REQ);
+	msg->msg_namelen = 0;
 
-		caif_assert(cf_sk->read_queue_len >= 0);
-	}
+	/*
+	 * Lock the socket to prevent queue disordering
+	 * while sleeps in memcpy_tomsg
+	 */
+	err = -EAGAIN;
+	if (sk->sk_state == CAIF_CONNECTING)
+		goto out;
 
-	skb = cfpkt_tonative(pkt);
-	result = skb_copy_datagram_iovec(skb, 0, m->msg_iov, len);
-	skb_pull(skb, len);
+	caif_read_lock(sk);
+	target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
+	timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
 
-	if (result) {
-		pr_debug("CAIF: %s(): copy to_iovec failed\n", __func__);
-		cfpkt_destroy(pkt);
-		ret = -EFAULT;
-		goto read_error;
-	}
+	do {
+		int chunk;
+		struct sk_buff *skb;
 
-	/* Free packet and remove from queue */
-	if (skb->len == 0)
-		skb_free_datagram(sk, skb);
+		lock_sock(sk);
+		skb = skb_dequeue(&sk->sk_receive_queue);
+		caif_check_flow_release(sk);
 
-	/* Let the others in. */
-	release_sock(&cf_sk->sk);
-	return len;
+		if (skb == NULL) {
+			if (copied >= target)
+				goto unlock;
+			/*
+			 *	POSIX 1003.1g mandates this order.
+			 */
+			err = sock_error(sk);
+			if (err)
+				goto unlock;
+			err = -ECONNRESET;
+			if (sk->sk_shutdown & RCV_SHUTDOWN)
+				goto unlock;
 
-read_error:
-	release_sock(&cf_sk->sk);
-read_error_no_unlock:
-	return ret;
-}
+			err = -EPIPE;
+			if (sk->sk_state != CAIF_CONNECTED)
+				goto unlock;
+			if (sock_flag(sk, SOCK_DEAD))
+				goto unlock;
 
-/* Send a signal as a consequence of sendmsg, sendto or caif_sendmsg. */
-static int caif_sendmsg(struct kiocb *kiocb, struct socket *sock,
-			struct msghdr *msg, size_t len)
-{
+			release_sock(sk);
 
-	struct sock *sk = sock->sk;
-	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
-	size_t payload_size = msg->msg_iov->iov_len;
-	struct cfpkt *pkt = NULL;
-	struct caif_payload_info info;
-	unsigned char *txbuf;
-	ssize_t ret = -EIO;
-	int result;
-	struct sk_buff *skb;
-	caif_assert(msg->msg_iovlen == 1);
+			err = -EAGAIN;
+			if (!timeo)
+				break;
 
-	if (cf_sk == NULL) {
-		pr_debug("CAIF: %s(): private_data not set!\n",
-			      __func__);
-		ret = -EBADFD;
-		goto write_error_no_unlock;
-	}
+			caif_read_unlock(sk);
 
-	if (unlikely(msg->msg_iov->iov_base == NULL)) {
-		pr_warning("CAIF: %s(): Buffer is NULL.\n", __func__);
-		ret = -EINVAL;
-		goto write_error_no_unlock;
-	}
+			timeo = caif_stream_data_wait(sk, timeo);
 
-	if (payload_size > CAIF_MAX_PAYLOAD_SIZE) {
-		pr_debug("CAIF: %s(): buffer too long\n", __func__);
-		if (sock->type == SOCK_SEQPACKET) {
-			ret = -EINVAL;
-			goto write_error_no_unlock;
+			if (signal_pending(current)) {
+				err = sock_intr_errno(timeo);
+				goto out;
+			}
+			caif_read_lock(sk);
+			continue;
+unlock:
+			release_sock(sk);
+			break;
 		}
-		payload_size = CAIF_MAX_PAYLOAD_SIZE;
-	}
+		release_sock(sk);
+		chunk = min_t(unsigned int, skb->len, size);
+		if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
+			skb_queue_head(&sk->sk_receive_queue, skb);
+			if (copied == 0)
+				copied = -EFAULT;
+			break;
+		}
+		copied += chunk;
+		size -= chunk;
 
-	/* I want to be alone on cf_sk (except status and queue) */
-	lock_sock(&(cf_sk->sk));
+		/* Mark read part of skb as used */
+		if (!(flags & MSG_PEEK)) {
+			skb_pull(skb, chunk);
 
-	caif_assert(cf_sk->pktq);
+			/* put the skb back if we didn't use it up. */
+			if (skb->len) {
+				skb_queue_head(&sk->sk_receive_queue, skb);
+				break;
+			}
+			kfree_skb(skb);
 
-	if (!STATE_IS_OPEN(cf_sk)) {
-		/* Socket is closed or closing */
-		if (!STATE_IS_PENDING(cf_sk)) {
-			pr_debug("CAIF: %s(): socket is closed (by remote)\n",
-				 __func__);
-			ret = -EPIPE;
 		} else {
-			pr_debug("CAIF: %s(): socket is closing...\n",
-				 __func__);
-			ret = -EBADF;
-		}
-		goto write_error;
-	}
-
-	/* Socket is open or opening */
-	if (STATE_IS_PENDING(cf_sk)) {
-		pr_debug("CAIF: %s(): socket is opening...\n", __func__);
-
-		if (msg->msg_flags & MSG_DONTWAIT) {
-			/* We can't block */
-			trace_printk("CAIF: %s():state pending:"
-				     "state=MSG_DONTWAIT\n", __func__);
-			ret = -EAGAIN;
-			goto write_error;
+			/*
+			 * It is questionable, see note in unix_dgram_recvmsg.
+			 */
+			/* put message back and return */
+			skb_queue_head(&sk->sk_receive_queue, skb);
+			break;
 		}
-		/* Let readers in */
-		release_sock(&cf_sk->sk);
-
-		/*
-		 * Blocking mode; state is pending and we need to wait
-		 * for its conclusion.
-		 */
-		result =
-		    wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-					     !STATE_IS_PENDING(cf_sk));
-		/* I want to be alone on cf_sk (except status and queue) */
-		lock_sock(&(cf_sk->sk));
+	} while (size);
+	caif_read_unlock(sk);
 
-		if (result == -ERESTARTSYS) {
-			pr_debug("CAIF: %s(): wait_event_interruptible"
-				 " woken by a signal (1)", __func__);
-			ret = -ERESTARTSYS;
-			goto write_error;
-		}
-	}
-	if (STATE_IS_REMOTE_SHUTDOWN(cf_sk) ||
-		!STATE_IS_OPEN(cf_sk) ||
-		STATE_IS_PENDING(cf_sk)) {
+out:
+	return copied ? : err;
+}
 
-		pr_debug("CAIF: %s(): socket closed\n",
-			__func__);
-		ret = -ESHUTDOWN;
-		goto write_error;
+/*
+ * Copied from sock.c:sock_wait_for_wmem, but change to wait for
+ * CAIF flow-on and sock_writable.
+ */
+static long caif_wait_for_flow_on(struct caifsock *cf_sk,
+				int wait_writeable, long timeo, int *err)
+{
+	struct sock *sk = &cf_sk->sk;
+	DEFINE_WAIT(wait);
+	for (;;) {
+		*err = 0;
+		if (tx_flow_is_on(cf_sk) &&
+			(!wait_writeable || sock_writeable(&cf_sk->sk)))
+			break;
+		*err = -ETIMEDOUT;
+		if (!timeo)
+			break;
+		*err = -ERESTARTSYS;
+		if (signal_pending(current))
+			break;
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		*err = -ECONNRESET;
+		if (sk->sk_shutdown & SHUTDOWN_MASK)
+			break;
+		*err = -sk->sk_err;
+		if (sk->sk_err)
+			break;
+		*err = -EPIPE;
+		if (cf_sk->sk.sk_state != CAIF_CONNECTED)
+			break;
+		timeo = schedule_timeout(timeo);
 	}
+	finish_wait(sk_sleep(sk), &wait);
+	return timeo;
+}
 
-	if (!TX_FLOW_IS_ON(cf_sk)) {
+/*
+ * Transmit a SKB. The device may temporarily request re-transmission
+ * by returning EAGAIN.
+ */
+static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
+			int noblock, long timeo)
+{
+	struct cfpkt *pkt;
+	int ret, loopcnt = 0;
 
-		/* Flow is off. Check non-block flag */
-		if (msg->msg_flags & MSG_DONTWAIT) {
-			trace_printk("CAIF: %s(): MSG_DONTWAIT and tx flow off",
-				 __func__);
-			ret = -EAGAIN;
-			goto write_error;
-		}
+	pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
+	memset(cfpkt_info(pkt), 0, sizeof(struct caif_payload_info));
+	do {
 
-		/* release lock before waiting */
-		release_sock(&cf_sk->sk);
+		ret = -ETIMEDOUT;
 
-		/* Wait until flow is on or socket is closed */
-		if (wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-					TX_FLOW_IS_ON(cf_sk)
-					|| !STATE_IS_OPEN(cf_sk)
-					|| STATE_IS_REMOTE_SHUTDOWN(cf_sk)
-					) == -ERESTARTSYS) {
-			pr_debug("CAIF: %s():"
-				 " wait_event_interruptible woken by a signal",
-				 __func__);
-			ret = -ERESTARTSYS;
-			goto write_error_no_unlock;
+		/* Slight paranoia, probably not needed. */
+		if (unlikely(loopcnt++ > 1000)) {
+			pr_warning("CAIF: %s(): transmit retries failed,"
+				" error = %d\n", __func__, ret);
+			break;
 		}
 
-		/* I want to be alone on cf_sk (except status and queue) */
-		lock_sock(&(cf_sk->sk));
-
-		if (!STATE_IS_OPEN(cf_sk)) {
-			/* someone closed the link, report error */
-			pr_debug("CAIF: %s(): remote end shutdown!\n",
-				      __func__);
-			ret = -EPIPE;
-			goto write_error;
+		if (cf_sk->layer.dn != NULL)
+			ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
+		if (likely(ret >= 0))
+			break;
+		/* if transmit return -EAGAIN, then retry */
+		if (noblock && ret == -EAGAIN)
+			break;
+		timeo = caif_wait_for_flow_on(cf_sk, 0, timeo, &ret);
+		if (signal_pending(current)) {
+			ret = sock_intr_errno(timeo);
+			break;
 		}
-
-		if (STATE_IS_REMOTE_SHUTDOWN(cf_sk)) {
-			pr_debug("CAIF: %s(): "
-				 "received remote_shutdown indication\n",
-				 __func__);
-			ret = -ESHUTDOWN;
-			goto write_error;
+		if (ret)
+			break;
+		if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
+			sock_flag(&cf_sk->sk, SOCK_DEAD) ||
+			(cf_sk->sk.sk_shutdown & RCV_SHUTDOWN)) {
+			ret = -EPIPE;
+			cf_sk->sk.sk_err = EPIPE;
+			break;
 		}
-	}
+	} while (ret == -EAGAIN);
+	return ret;
+}
 
-	pkt = cfpkt_create(payload_size);
-	skb = (struct sk_buff *)pkt;
-	skb->destructor = skb_destructor;
-	skb->sk = sk;
-	dbfs_atomic_inc(&cnt.skb_alloc);
-	dbfs_atomic_inc(&cnt.skb_in_use);
-	if (cfpkt_raw_append(pkt, (void **) &txbuf, payload_size) < 0) {
-		pr_debug("CAIF: %s(): cfpkt_raw_append failed\n", __func__);
-		cfpkt_destroy(pkt);
-		ret = -EINVAL;
-		goto write_error;
-	}
+/* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
+static int caif_seqpkt_sendmsg(struct kiocb *kiocb, struct socket *sock,
+			struct msghdr *msg, size_t len)
+{
+	struct sock *sk = sock->sk;
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+	int buffer_size;
+	int ret = 0;
+	struct sk_buff *skb = NULL;
+	int noblock;
+	long timeo;
+	caif_assert(cf_sk);
+	ret = sock_error(sk);
+	if (ret)
+		goto err;
+
+	ret = -EOPNOTSUPP;
+	if (msg->msg_flags&MSG_OOB)
+		goto err;
+
+	ret = -EOPNOTSUPP;
+	if (msg->msg_namelen)
+		goto err;
+
+	ret = -EINVAL;
+	if (unlikely(msg->msg_iov->iov_base == NULL))
+		goto err;
+	noblock = msg->msg_flags & MSG_DONTWAIT;
+
+	buffer_size = len + CAIF_NEEDED_HEADROOM + CAIF_NEEDED_TAILROOM;
+
+	ret = -EMSGSIZE;
+	if (buffer_size > CAIF_MAX_PAYLOAD_SIZE)
+		goto err;
+
+	timeo = sock_sndtimeo(sk, noblock);
+	timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
+				1, timeo, &ret);
+
+	ret = -EPIPE;
+	if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
+		sock_flag(sk, SOCK_DEAD) ||
+		(sk->sk_shutdown & RCV_SHUTDOWN))
+		goto err;
+
+	ret = -ENOMEM;
+	skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
+	if (!skb)
+		goto err;
+	skb_reserve(skb, CAIF_NEEDED_HEADROOM);
+
+	ret = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
+
+	if (ret)
+		goto err;
+	ret = transmit_skb(skb, cf_sk, noblock, timeo);
+	if (ret < 0)
+		goto err;
+	return len;
+err:
+	kfree_skb(skb);
+	return ret;
+}
 
-	/* Copy data into buffer. */
-	if (copy_from_user(txbuf, msg->msg_iov->iov_base, payload_size)) {
-		pr_debug("CAIF: %s(): copy_from_user returned non zero.\n",
-			 __func__);
-		cfpkt_destroy(pkt);
-		ret = -EINVAL;
-		goto write_error;
-	}
-	memset(&info, 0, sizeof(info));
+/*
+ * Copied from unix_stream_sendmsg and adapted to CAIF:
+ * Changed removed permission handling and added waiting for flow on
+ * and other minor adaptations.
+ */
+static int caif_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
+				struct msghdr *msg, size_t len)
+{
+	struct sock *sk = sock->sk;
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+	int err, size;
+	struct sk_buff *skb;
+	int sent = 0;
+	long timeo;
 
-	/* Send the packet down the stack. */
-	caif_assert(cf_sk->layer.dn);
-	caif_assert(cf_sk->layer.dn->transmit);
+	err = -EOPNOTSUPP;
 
-	do {
-		ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
+	if (unlikely(msg->msg_flags&MSG_OOB))
+		goto out_err;
 
-		if (likely((ret >= 0) || (ret != -EAGAIN)))
-			break;
+	if (unlikely(msg->msg_namelen))
+		goto out_err;
 
-		/* EAGAIN - retry */
-		if (msg->msg_flags & MSG_DONTWAIT) {
-			pr_debug("CAIF: %s(): NONBLOCK and transmit failed,"
-				 " error = %ld\n", __func__, (long) ret);
-			ret = -EAGAIN;
-			goto write_error;
-		}
+	timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+	timeo = caif_wait_for_flow_on(cf_sk, 1, timeo, &err);
 
-		/* Let readers in */
-		release_sock(&cf_sk->sk);
+	if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN))
+		goto pipe_err;
 
-		/* Wait until flow is on or socket is closed */
-		if (wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-					TX_FLOW_IS_ON(cf_sk)
-					|| !STATE_IS_OPEN(cf_sk)
-					|| STATE_IS_REMOTE_SHUTDOWN(cf_sk)
-					) == -ERESTARTSYS) {
-			pr_debug("CAIF: %s(): wait_event_interruptible"
-				 " woken by a signal", __func__);
-			ret = -ERESTARTSYS;
-			goto write_error_no_unlock;
-		}
+	while (sent < len) {
 
-		/* I want to be alone on cf_sk (except status and queue) */
-		lock_sock(&(cf_sk->sk));
+		size = len-sent;
 
-	} while (ret == -EAGAIN);
+		if (size > CAIF_MAX_PAYLOAD_SIZE)
+			size = CAIF_MAX_PAYLOAD_SIZE;
 
-	if (ret < 0) {
-		cfpkt_destroy(pkt);
-		pr_debug("CAIF: %s(): transmit failed, error = %ld\n",
-			 __func__, (long) ret);
+		/* If size is more than half of sndbuf, chop up message */
+		if (size > ((sk->sk_sndbuf >> 1) - 64))
+			size = (sk->sk_sndbuf >> 1) - 64;
 
-		goto write_error;
-	}
+		if (size > SKB_MAX_ALLOC)
+			size = SKB_MAX_ALLOC;
 
-	release_sock(&cf_sk->sk);
-	return payload_size;
+		skb = sock_alloc_send_skb(sk,
+					size + CAIF_NEEDED_HEADROOM
+					+ CAIF_NEEDED_TAILROOM,
+					msg->msg_flags&MSG_DONTWAIT,
+					&err);
+		if (skb == NULL)
+			goto out_err;
 
-write_error:
-	release_sock(&cf_sk->sk);
-write_error_no_unlock:
-	return ret;
-}
+		skb_reserve(skb, CAIF_NEEDED_HEADROOM);
+		/*
+		 *	If you pass two values to the sock_alloc_send_skb
+		 *	it tries to grab the large buffer with GFP_NOFS
+		 *	(which can fail easily), and if it fails grab the
+		 *	fallback size buffer which is under a page and will
+		 *	succeed. [Alan]
+		 */
+		size = min_t(int, size, skb_tailroom(skb));
 
-static unsigned int caif_poll(struct file *file, struct socket *sock,
-						poll_table *wait)
-{
-	struct sock *sk = sock->sk;
-	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
-	u32 mask = 0;
-	poll_wait(file, sk_sleep(sk), wait);
-	lock_sock(&(cf_sk->sk));
-	if (!STATE_IS_OPEN(cf_sk)) {
-		if (!STATE_IS_PENDING(cf_sk))
-			mask |= POLLHUP;
-	} else {
-		if (cfpkt_qpeek(cf_sk->pktq) != NULL)
-			mask |= (POLLIN | POLLRDNORM);
-		if (TX_FLOW_IS_ON(cf_sk))
-			mask |= (POLLOUT | POLLWRNORM);
+		err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
+		if (err) {
+			kfree_skb(skb);
+			goto out_err;
+		}
+		err = transmit_skb(skb, cf_sk,
+				msg->msg_flags&MSG_DONTWAIT, timeo);
+		if (err < 0) {
+			kfree_skb(skb);
+			goto pipe_err;
+		}
+		sent += size;
 	}
-	release_sock(&cf_sk->sk);
-	trace_printk("CAIF: %s(): poll mask=0x%04x\n",
-		      __func__, mask);
-	return mask;
-}
-
-static void drain_queue(struct caifsock *cf_sk)
-{
-	struct cfpkt *pkt = NULL;
-
-	/* Empty the queue */
-	do {
-		/* The queue has its own lock */
-		if (!cf_sk->pktq)
-			break;
-
-		pkt = cfpkt_dequeue(cf_sk->pktq);
-		if (!pkt)
-			break;
-		pr_debug("CAIF: %s(): freeing packet from read queue\n",
-			 __func__);
-		cfpkt_destroy(pkt);
 
-	} while (1);
+	return sent;
 
-	cf_sk->read_queue_len = 0;
+pipe_err:
+	if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
+		send_sig(SIGPIPE, current, 0);
+	err = -EPIPE;
+out_err:
+	return sent ? : err;
 }
 
 static int setsockopt(struct socket *sock,
@@ -736,19 +738,13 @@ static int setsockopt(struct socket *sock,
 	int prio, linksel;
 	struct ifreq ifreq;
 
-	if (STATE_IS_OPEN(cf_sk)) {
-		pr_debug("CAIF: %s(): setsockopt "
-			 "cannot be done on a connected socket\n",
-			 __func__);
+	if (cf_sk->sk.sk_socket->state != SS_UNCONNECTED)
 		return -ENOPROTOOPT;
-	}
+
 	switch (opt) {
 	case CAIFSO_LINK_SELECT:
-		if (ol < sizeof(int)) {
-			pr_debug("CAIF: %s(): setsockopt"
-				 " CAIFSO_CHANNEL_CONFIG bad size\n", __func__);
+		if (ol < sizeof(int))
 			return -EINVAL;
-		}
 		if (lvl != SOL_CAIF)
 			goto bad_sol;
 		if (copy_from_user(&linksel, ov, sizeof(int)))
@@ -761,28 +757,20 @@ static int setsockopt(struct socket *sock,
 	case SO_PRIORITY:
 		if (lvl != SOL_SOCKET)
 			goto bad_sol;
-		if (ol < sizeof(int)) {
-			pr_debug("CAIF: %s(): setsockopt"
-				 " SO_PRIORITY bad size\n", __func__);
+		if (ol < sizeof(int))
 			return -EINVAL;
-		}
 		if (copy_from_user(&prio, ov, sizeof(int)))
 			return -EINVAL;
 		lock_sock(&(cf_sk->sk));
 		cf_sk->conn_req.priority = prio;
-		pr_debug("CAIF: %s(): Setting sockopt priority=%d\n", __func__,
-			cf_sk->conn_req.priority);
 		release_sock(&cf_sk->sk);
 		return 0;
 
 	case SO_BINDTODEVICE:
 		if (lvl != SOL_SOCKET)
 			goto bad_sol;
-		if (ol < sizeof(struct ifreq)) {
-			pr_debug("CAIF: %s(): setsockopt"
-				 " SO_PRIORITY bad size\n", __func__);
+		if (ol < sizeof(struct ifreq))
 			return -EINVAL;
-		}
 		if (copy_from_user(&ifreq, ov, sizeof(ifreq)))
 			return -EFAULT;
 		lock_sock(&(cf_sk->sk));
@@ -798,359 +786,275 @@ static int setsockopt(struct socket *sock,
 			goto bad_sol;
 		if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL)
 			return -ENOPROTOOPT;
-		if (ol > sizeof(cf_sk->conn_req.param.data))
-			goto req_param_bad_size;
-
 		lock_sock(&(cf_sk->sk));
 		cf_sk->conn_req.param.size = ol;
-		if (copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
+		if (ol > sizeof(cf_sk->conn_req.param.data) ||
+			copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
 			release_sock(&cf_sk->sk);
-req_param_bad_size:
-			pr_debug("CAIF: %s(): setsockopt"
-				 " CAIFSO_CHANNEL_CONFIG bad size\n", __func__);
 			return -EINVAL;
 		}
-
 		release_sock(&cf_sk->sk);
 		return 0;
 
 	default:
-		pr_debug("CAIF: %s(): unhandled option %d\n", __func__, opt);
-		return -EINVAL;
+		return -ENOPROTOOPT;
 	}
 
 	return 0;
 bad_sol:
-	pr_debug("CAIF: %s(): setsockopt bad level\n", __func__);
 	return -ENOPROTOOPT;
 
 }
 
-static int caif_connect(struct socket *sock, struct sockaddr *uservaddr,
-	       int sockaddr_len, int flags)
+/*
+ * caif_connect() - Connect a CAIF Socket
+ * Copied and modified af_irda.c:irda_connect().
+ *
+ * Note : by consulting "errno", the user space caller may learn the cause
+ * of the failure. Most of them are visible in the function, others may come
+ * from subroutines called and are listed here :
+ *  o -EAFNOSUPPORT: bad socket family or type.
+ *  o -ESOCKTNOSUPPORT: bad socket type or protocol
+ *  o -EINVAL: bad socket address, or CAIF link type
+ *  o -ECONNREFUSED: remote end refused the connection.
+ *  o -EINPROGRESS: connect request sent but timed out (or non-blocking)
+ *  o -EISCONN: already connected.
+ *  o -ETIMEDOUT: Connection timed out (send timeout)
+ *  o -ENODEV: No link layer to send request
+ *  o -ECONNRESET: Received Shutdown indication or lost link layer
+ *  o -ENOMEM: Out of memory
+ *
+ *  State Strategy:
+ *  o sk_state: holds the CAIF_* protocol state, it's updated by
+ *	caif_ctrl_cb.
+ *  o sock->state: holds the SS_* socket state and is updated by connect and
+ *	disconnect.
+ */
+static int caif_connect(struct socket *sock, struct sockaddr *uaddr,
+			int addr_len, int flags)
 {
-	struct caifsock *cf_sk = NULL;
-	int result = -1;
-	int mode = 0;
-	int ret = -EIO;
 	struct sock *sk = sock->sk;
-	BUG_ON(sk == NULL);
-
-	cf_sk = container_of(sk, struct caifsock, sk);
-
-	trace_printk("CAIF: %s(): cf_sk=%p OPEN=%d, TX_FLOW=%d, RX_FLOW=%d\n",
-		 __func__, cf_sk,
-		STATE_IS_OPEN(cf_sk),
-		TX_FLOW_IS_ON(cf_sk), RX_FLOW_IS_ON(cf_sk));
-
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+	long timeo;
+	int err;
+	lock_sock(sk);
 
-	if (sock->type == SOCK_SEQPACKET || sock->type == SOCK_STREAM)
-		sock->state	= SS_CONNECTING;
-	else
+	err = -EAFNOSUPPORT;
+	if (uaddr->sa_family != AF_CAIF)
 		goto out;
 
-	/* I want to be alone on cf_sk (except status and queue) */
-	lock_sock(&(cf_sk->sk));
-
-	if (sockaddr_len != sizeof(struct sockaddr_caif)) {
-		pr_debug("CAIF: %s(): Bad address len (%ld,%lu)\n",
-			 __func__, (long) sockaddr_len,
-			(long unsigned) sizeof(struct sockaddr_caif));
-		ret = -EINVAL;
-		goto open_error;
+	err = -ESOCKTNOSUPPORT;
+	if (unlikely(!(sk->sk_type == SOCK_STREAM &&
+		       cf_sk->sk.sk_protocol == CAIFPROTO_AT) &&
+		       sk->sk_type != SOCK_SEQPACKET))
+		goto out;
+	switch (sock->state) {
+	case SS_UNCONNECTED:
+		/* Normal case, a fresh connect */
+		caif_assert(sk->sk_state == CAIF_DISCONNECTED);
+		break;
+	case SS_CONNECTING:
+		switch (sk->sk_state) {
+		case CAIF_CONNECTED:
+			sock->state = SS_CONNECTED;
+			err = -EISCONN;
+			goto out;
+		case CAIF_DISCONNECTED:
+			/* Reconnect allowed */
+			break;
+		case CAIF_CONNECTING:
+			err = -EALREADY;
+			if (flags & O_NONBLOCK)
+				goto out;
+			goto wait_connect;
+		}
+		break;
+	case SS_CONNECTED:
+		caif_assert(sk->sk_state == CAIF_CONNECTED ||
+				sk->sk_state == CAIF_DISCONNECTED);
+		if (sk->sk_shutdown & SHUTDOWN_MASK) {
+			/* Allow re-connect after SHUTDOWN_IND */
+			caif_disconnect_client(&cf_sk->layer);
+			break;
+		}
+		/* No reconnect on a seqpacket socket */
+		err = -EISCONN;
+		goto out;
+	case SS_DISCONNECTING:
+	case SS_FREE:
+		caif_assert(1); /*Should never happen */
+		break;
 	}
+	sk->sk_state = CAIF_DISCONNECTED;
+	sock->state = SS_UNCONNECTED;
+	sk_stream_kill_queues(&cf_sk->sk);
 
-	if (uservaddr->sa_family != AF_CAIF) {
-		pr_debug("CAIF: %s(): Bad address family (%d)\n",
-			 __func__, uservaddr->sa_family);
-		ret = -EAFNOSUPPORT;
-		goto open_error;
-	}
+	err = -EINVAL;
+	if (addr_len != sizeof(struct sockaddr_caif) ||
+		!uaddr)
+		goto out;
 
-	memcpy(&cf_sk->conn_req.sockaddr, uservaddr,
+	memcpy(&cf_sk->conn_req.sockaddr, uaddr,
 		sizeof(struct sockaddr_caif));
 
-	dbfs_atomic_inc(&cnt.num_open);
-	mode = SKT_READ_FLAG | SKT_WRITE_FLAG;
-
-	/* If socket is not open, make sure socket is in fully closed state */
-	if (!STATE_IS_OPEN(cf_sk)) {
-		/* Has link close response been received (if we ever sent it)?*/
-		if (STATE_IS_PENDING(cf_sk)) {
-			/*
-			 * Still waiting for close response from remote.
-			 * If opened non-blocking, report "would block"
-			 */
-			if (flags & O_NONBLOCK) {
-				pr_debug("CAIF: %s(): O_NONBLOCK"
-					" && close pending\n", __func__);
-				ret = -EAGAIN;
-				goto open_error;
-			}
-
-			pr_debug("CAIF: %s(): Wait for close response"
-				 " from remote...\n", __func__);
-
-			release_sock(&cf_sk->sk);
-
-			/*
-			 * Blocking mode; close is pending and we need to wait
-			 * for its conclusion.
-			 */
-			result =
-			    wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-						     !STATE_IS_PENDING(cf_sk));
-
-			lock_sock(&(cf_sk->sk));
-			if (result == -ERESTARTSYS) {
-				pr_debug("CAIF: %s(): wait_event_interruptible"
-					 "woken by a signal (1)", __func__);
-				ret = -ERESTARTSYS;
-				goto open_error;
-			}
-		}
+	/* Move to connecting socket, start sending Connect Requests */
+	sock->state = SS_CONNECTING;
+	sk->sk_state = CAIF_CONNECTING;
+
+	dbfs_atomic_inc(&cnt.num_connect_req);
+	cf_sk->layer.receive = caif_sktrecv_cb;
+	err = caif_connect_client(&cf_sk->conn_req,
+				&cf_sk->layer);
+	if (err < 0) {
+		cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
+		cf_sk->sk.sk_state = CAIF_DISCONNECTED;
+		goto out;
 	}
 
-	/* socket is now either closed, pending open or open */
-	if (STATE_IS_OPEN(cf_sk) && !STATE_IS_PENDING(cf_sk)) {
-		/* Open */
-		pr_debug("CAIF: %s(): Socket is already opened (cf_sk=%p)"
-			" check access f_flags = 0x%x file_mode = 0x%x\n",
-			 __func__, cf_sk, mode, cf_sk->file_mode);
-
-	} else {
-		/* We are closed or pending open.
-		 * If closed:	    send link setup
-		 * If pending open: link setup already sent (we could have been
-		 *		    interrupted by a signal last time)
-		 */
-		if (!STATE_IS_OPEN(cf_sk)) {
-			/* First opening of file; connect lower layers: */
-			/* Drain queue (very unlikely) */
-			drain_queue(cf_sk);
-
-			cf_sk->layer.receive = caif_sktrecv_cb;
-			SET_STATE_OPEN(cf_sk);
-			SET_PENDING_ON(cf_sk);
-
-			/* Register this channel. */
-			result =
-				caif_connect_client(&cf_sk->conn_req,
-							&cf_sk->layer);
-			if (result < 0) {
-				pr_debug("CAIF: %s(): can't register channel\n",
-					__func__);
-				ret = -EIO;
-				SET_STATE_CLOSED(cf_sk);
-				SET_PENDING_OFF(cf_sk);
-				goto open_error;
-			}
-			dbfs_atomic_inc(&cnt.num_init);
-		}
-
-		/* If opened non-blocking, report "success".
-		 */
-		if (flags & O_NONBLOCK) {
-			pr_debug("CAIF: %s(): O_NONBLOCK success\n",
-				 __func__);
-			ret = -EINPROGRESS;
-			cf_sk->sk.sk_err = -EINPROGRESS;
-			goto open_error;
-		}
-
-		trace_printk("CAIF: %s(): Wait for connect response\n",
-			     __func__);
+	err = -EINPROGRESS;
+wait_connect:
 
-		/* release lock before waiting */
-		release_sock(&cf_sk->sk);
-
-		result =
-		    wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-					     !STATE_IS_PENDING(cf_sk));
-
-		lock_sock(&(cf_sk->sk));
-
-		if (result == -ERESTARTSYS) {
-			pr_debug("CAIF: %s(): wait_event_interruptible"
-				 "woken by a signal (2)", __func__);
-			ret = -ERESTARTSYS;
-			goto open_error;
-		}
-
-		if (!STATE_IS_OPEN(cf_sk)) {
-			/* Lower layers said "no" */
-			pr_debug("CAIF: %s(): Closed received\n", __func__);
-			ret = -EPIPE;
-			goto open_error;
-		}
+	if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
+		goto out;
 
-		trace_printk("CAIF: %s(): Connect received\n", __func__);
+	timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
+
+	release_sock(sk);
+	err = wait_event_interruptible_timeout(*sk_sleep(sk),
+			sk->sk_state != CAIF_CONNECTING,
+			timeo);
+	lock_sock(sk);
+	if (err < 0)
+		goto out; /* -ERESTARTSYS */
+	if (err == 0 && sk->sk_state != CAIF_CONNECTED) {
+		err = -ETIMEDOUT;
+		goto out;
 	}
-	/* Open is ok */
-	cf_sk->file_mode |= mode;
 
-	trace_printk("CAIF: %s(): Connected - file mode = %x\n",
-		  __func__, cf_sk->file_mode);
-
-	release_sock(&cf_sk->sk);
-	return 0;
-open_error:
-	sock->state	= SS_UNCONNECTED;
-	release_sock(&cf_sk->sk);
+	if (sk->sk_state != CAIF_CONNECTED) {
+		sock->state = SS_UNCONNECTED;
+		err = sock_error(sk);
+		if (!err)
+			err = -ECONNREFUSED;
+		goto out;
+	}
+	sock->state = SS_CONNECTED;
+	err = 0;
 out:
-	return ret;
+	release_sock(sk);
+	return err;
 }
 
-static int caif_shutdown(struct socket *sock, int how)
+
+/*
+ * caif_release() - Disconnect a CAIF Socket
+ * Copied and modified af_irda.c:irda_release().
+ */
+static int caif_release(struct socket *sock)
 {
-	struct caifsock *cf_sk = NULL;
-	int result = 0;
-	int tx_flow_state_was_on;
 	struct sock *sk = sock->sk;
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+	int res = 0;
 
-	trace_printk("CAIF: %s(): enter\n", __func__);
-	pr_debug("f_flags=%x\n", sock->file->f_flags);
-
-	if (how != SHUT_RDWR)
-		return -EOPNOTSUPP;
-
-	cf_sk = container_of(sk, struct caifsock, sk);
-	if (cf_sk == NULL) {
-		pr_debug("CAIF: %s(): COULD NOT FIND SOCKET\n", __func__);
-		return -EBADF;
-	}
-
-	/* I want to be alone on cf_sk (except status queue) */
-	lock_sock(&(cf_sk->sk));
-	sock_hold(&cf_sk->sk);
-
-	/* IS_CLOSED have double meaning:
-	 * 1) Spontanous Remote Shutdown Request.
-	 * 2) Ack on a channel teardown(disconnect)
-	 * Must clear bit in case we previously received
-	 * remote shudown request.
-	 */
-	if (STATE_IS_OPEN(cf_sk) && !STATE_IS_PENDING(cf_sk)) {
-		SET_STATE_CLOSED(cf_sk);
-		SET_PENDING_ON(cf_sk);
-		tx_flow_state_was_on = TX_FLOW_IS_ON(cf_sk);
-		SET_TX_FLOW_OFF(cf_sk);
-
-		/* Hold the socket until DEINIT_RSP is received */
-		sock_hold(&cf_sk->sk);
-		result = caif_disconnect_client(&cf_sk->layer);
-
-		if (result < 0) {
-			pr_debug("CAIF: %s(): "
-					"caif_disconnect_client() failed\n",
-					 __func__);
-			SET_STATE_CLOSED(cf_sk);
-			SET_PENDING_OFF(cf_sk);
-			SET_TX_FLOW_OFF(cf_sk);
-			release_sock(&cf_sk->sk);
-			sock_put(&cf_sk->sk);
-			return -EIO;
-		}
+	if (!sk)
+		return 0;
 
-	}
-	if (STATE_IS_REMOTE_SHUTDOWN(cf_sk)) {
-		SET_PENDING_OFF(cf_sk);
-		SET_REMOTE_SHUTDOWN_OFF(cf_sk);
-	}
+	set_tx_flow_off(cf_sk);
 
 	/*
-	 * Socket is no longer in state pending close,
-	 * and we can release the reference.
+	 * Ensure that packets are not queued after this point in time.
+	 * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
+	 * this ensures no packets when sock is dead.
 	 */
+	spin_lock(&sk->sk_receive_queue.lock);
+	sock_set_flag(sk, SOCK_DEAD);
+	spin_unlock(&sk->sk_receive_queue.lock);
+	sock->sk = NULL;
 
-	dbfs_atomic_inc(&cnt.num_close);
-	drain_queue(cf_sk);
-	SET_RX_FLOW_ON(cf_sk);
-	cf_sk->file_mode = 0;
-	sock_put(&cf_sk->sk);
-	release_sock(&cf_sk->sk);
-	if (!result && (sock->file->f_flags & O_NONBLOCK)) {
-		pr_debug("nonblocking shutdown returing -EAGAIN\n");
-		return -EAGAIN;
-	} else
-		return result;
-}
-
-static ssize_t caif_sock_no_sendpage(struct socket *sock,
-				     struct page *page,
-				     int offset, size_t size, int flags)
-{
-	return -EOPNOTSUPP;
-}
-
-/* This function is called as part of close. */
-static int caif_release(struct socket *sock)
-{
-	struct sock *sk = sock->sk;
-	struct caifsock *cf_sk = NULL;
-	int res;
-	caif_assert(sk != NULL);
-	cf_sk = container_of(sk, struct caifsock, sk);
+	dbfs_atomic_inc(&cnt.num_disconnect);
 
 	if (cf_sk->debugfs_socket_dir != NULL)
 		debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
 
-	res = caif_shutdown(sock, SHUT_RDWR);
-	if (res && res != -EINPROGRESS)
-		return res;
-
-	/*
-	 * FIXME: Shutdown should probably be possible to do async
-	 * without flushing queues, allowing reception of frames while
-	 * waiting for DEINIT_IND.
-	 * Release should always block, to allow secure decoupling of
-	 * CAIF stack.
-	 */
-	if (!(sock->file->f_flags & O_NONBLOCK)) {
-		res = wait_event_interruptible(*sk_sleep(&cf_sk->sk),
-						!STATE_IS_PENDING(cf_sk));
-
-		if (res == -ERESTARTSYS) {
-			pr_debug("CAIF: %s(): wait_event_interruptible"
-				"woken by a signal (1)", __func__);
-		}
-	}
 	lock_sock(&(cf_sk->sk));
+	sk->sk_state = CAIF_DISCONNECTED;
+	sk->sk_shutdown = SHUTDOWN_MASK;
 
-	sock->sk = NULL;
+	if (cf_sk->sk.sk_socket->state == SS_CONNECTED ||
+		cf_sk->sk.sk_socket->state == SS_CONNECTING)
+		res = caif_disconnect_client(&cf_sk->layer);
 
-	/* Detach the socket from its process context by making it orphan. */
-	sock_orphan(sk);
+	cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
+	wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
 
-	/*
-	 * Setting SHUTDOWN_MASK means that both send and receive are shutdown
-	 * for the socket.
-	 */
-	sk->sk_shutdown = SHUTDOWN_MASK;
+	sock_orphan(sk);
+	cf_sk->layer.dn = NULL;
+	sk_stream_kill_queues(&cf_sk->sk);
+	release_sock(sk);
+	sock_put(sk);
+	return res;
+}
 
-	/*
-	 * Set the socket state to closed, the TCP_CLOSE macro is used when
-	 * closing any socket.
-	 */
+/* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
+static unsigned int caif_poll(struct file *file,
+				struct socket *sock, poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	unsigned int mask;
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 
-	/* Flush out this sockets receive queue. */
-	drain_queue(cf_sk);
+	sock_poll_wait(file, sk_sleep(sk), wait);
+	mask = 0;
 
-	/* Finally release the socket. */
-	SET_STATE_PENDING_DESTROY(cf_sk);
+	/* exceptional events? */
+	if (sk->sk_err)
+		mask |= POLLERR;
+	if (sk->sk_shutdown == SHUTDOWN_MASK)
+		mask |= POLLHUP;
+	if (sk->sk_shutdown & RCV_SHUTDOWN)
+		mask |= POLLRDHUP;
 
-	release_sock(&cf_sk->sk);
+	/* readable? */
+	if (!skb_queue_empty(&sk->sk_receive_queue) ||
+		(sk->sk_shutdown & RCV_SHUTDOWN))
+		mask |= POLLIN | POLLRDNORM;
 
-	sock_put(sk);
+	/* Connection-based need to check for termination and startup */
+	if (sk->sk_state == CAIF_DISCONNECTED)
+		mask |= POLLHUP;
 
 	/*
-	 * The rest of the cleanup will be handled from the
-	 * caif_sock_destructor
+	 * we set writable also when the other side has shut down the
+	 * connection. This prevents stuck sockets.
 	 */
-	return res;
+	if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
+		mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
+
+	return mask;
 }
 
-static const struct proto_ops caif_ops = {
+static const struct proto_ops caif_seqpacket_ops = {
+	.family = PF_CAIF,
+	.owner = THIS_MODULE,
+	.release = caif_release,
+	.bind = sock_no_bind,
+	.connect = caif_connect,
+	.socketpair = sock_no_socketpair,
+	.accept = sock_no_accept,
+	.getname = sock_no_getname,
+	.poll = caif_poll,
+	.ioctl = sock_no_ioctl,
+	.listen = sock_no_listen,
+	.shutdown = sock_no_shutdown,
+	.setsockopt = setsockopt,
+	.getsockopt = sock_no_getsockopt,
+	.sendmsg = caif_seqpkt_sendmsg,
+	.recvmsg = caif_seqpkt_recvmsg,
+	.mmap = sock_no_mmap,
+	.sendpage = sock_no_sendpage,
+};
+
+static const struct proto_ops caif_stream_ops = {
 	.family = PF_CAIF,
 	.owner = THIS_MODULE,
 	.release = caif_release,
@@ -1162,73 +1066,62 @@ static const struct proto_ops caif_ops = {
 	.poll = caif_poll,
 	.ioctl = sock_no_ioctl,
 	.listen = sock_no_listen,
-	.shutdown = caif_shutdown,
+	.shutdown = sock_no_shutdown,
 	.setsockopt = setsockopt,
 	.getsockopt = sock_no_getsockopt,
-	.sendmsg = caif_sendmsg,
-	.recvmsg = caif_recvmsg,
+	.sendmsg = caif_stream_sendmsg,
+	.recvmsg = caif_stream_recvmsg,
 	.mmap = sock_no_mmap,
-	.sendpage = caif_sock_no_sendpage,
+	.sendpage = sock_no_sendpage,
 };
 
 /* This function is called when a socket is finally destroyed. */
 static void caif_sock_destructor(struct sock *sk)
 {
-	struct caifsock *cf_sk = NULL;
-	cf_sk = container_of(sk, struct caifsock, sk);
-	/* Error checks. */
+	struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
 	caif_assert(!atomic_read(&sk->sk_wmem_alloc));
 	caif_assert(sk_unhashed(sk));
 	caif_assert(!sk->sk_socket);
 	if (!sock_flag(sk, SOCK_DEAD)) {
-		pr_debug("CAIF: %s(): 0x%p", __func__, sk);
+		pr_info("Attempt to release alive CAIF socket: %p\n", sk);
 		return;
 	}
-
-	if (STATE_IS_OPEN(cf_sk)) {
-		pr_debug("CAIF: %s(): socket is opened (cf_sk=%p)"
-			 " file_mode = 0x%x\n", __func__,
-			 cf_sk, cf_sk->file_mode);
-		return;
-	}
-	drain_queue(cf_sk);
-	kfree(cf_sk->pktq);
-
-	trace_printk("CAIF: %s(): caif_sock_destructor: Removing socket %s\n",
-		__func__, cf_sk->name);
-	atomic_dec(&caif_nr_socks);
+	sk_stream_kill_queues(&cf_sk->sk);
+	dbfs_atomic_dec(&cnt.caif_nr_socks);
 }
 
 static int caif_create(struct net *net, struct socket *sock, int protocol,
-		       int kern)
+			int kern)
 {
 	struct sock *sk = NULL;
 	struct caifsock *cf_sk = NULL;
-	int result = 0;
 	static struct proto prot = {.name = "PF_CAIF",
 		.owner = THIS_MODULE,
 		.obj_size = sizeof(struct caifsock),
 	};
 
+	if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
+		return -EPERM;
 	/*
 	 * The sock->type specifies the socket type to use.
-	 * in SEQPACKET mode packet boundaries are enforced.
+	 * The CAIF socket is a packet stream in the sense
+	 * that it is packet based. CAIF trusts the reliability
+	 * of the link, no resending is implemented.
 	 */
-	if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM)
+	if (sock->type == SOCK_SEQPACKET)
+		sock->ops = &caif_seqpacket_ops;
+	else if (sock->type == SOCK_STREAM)
+		sock->ops = &caif_stream_ops;
+	else
 		return -ESOCKTNOSUPPORT;
 
-	if (net != &init_net)
-		return -EAFNOSUPPORT;
-
 	if (protocol < 0 || protocol >= CAIFPROTO_MAX)
 		return -EPROTONOSUPPORT;
 	/*
-	 * Set the socket state to unconnected.	 The socket state is really
-	 * not used at all in the net/core or socket.c but the
+	 * Set the socket state to unconnected.	 The socket state
+	 * is really not used at all in the net/core or socket.c but the
 	 * initialization makes sure that sock->state is not uninitialized.
 	 */
-	sock->state = SS_UNCONNECTED;
-
 	sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot);
 	if (!sk)
 		return -ENOMEM;
@@ -1238,11 +1131,9 @@ static int caif_create(struct net *net, struct socket *sock, int protocol,
 	/* Store the protocol */
 	sk->sk_protocol = (unsigned char) protocol;
 
-	spin_lock_init(&cf_sk->read_queue_len_lock);
-
-	/* Fill in some information concerning the misc socket. */
-	snprintf(cf_sk->name, sizeof(cf_sk->name), "cf_sk%d",
-		atomic_read(&caif_nr_socks));
+	/* Sendbuf dictates the amount of outbound packets not yet sent */
+	sk->sk_sndbuf = CAIF_DEF_SNDBUF;
+	sk->sk_rcvbuf = CAIF_DEF_RCVBUF;
 
 	/*
 	 * Lock in order to try to stop someone from opening the socket
@@ -1252,108 +1143,85 @@ static int caif_create(struct net *net, struct socket *sock, int protocol,
 
 	/* Initialize the nozero default sock structure data. */
 	sock_init_data(sock, sk);
-	sock->ops = &caif_ops;
 	sk->sk_destruct = caif_sock_destructor;
-	sk->sk_sndbuf = caif_sockbuf_size;
-	sk->sk_rcvbuf = caif_sockbuf_size;
 
-	cf_sk->pktq = cfpktq_create();
+	mutex_init(&cf_sk->readlock); /* single task reading lock */
+	cf_sk->layer.ctrlcmd = caif_ctrl_cb;
+	cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
+	cf_sk->sk.sk_state = CAIF_DISCONNECTED;
 
-	if (!cf_sk->pktq) {
-		pr_err("CAIF: %s(): queue create failed.\n", __func__);
-		result = -ENOMEM;
-		release_sock(&cf_sk->sk);
-		goto err_failed;
-	}
-	cf_sk->layer.ctrlcmd = caif_sktflowctrl_cb;
-	SET_STATE_CLOSED(cf_sk);
-	SET_PENDING_OFF(cf_sk);
-	SET_TX_FLOW_OFF(cf_sk);
-	SET_RX_FLOW_ON(cf_sk);
+	set_tx_flow_off(cf_sk);
+	set_rx_flow_on(cf_sk);
 
 	/* Set default options on configuration */
 	cf_sk->conn_req.priority = CAIF_PRIO_NORMAL;
-	cf_sk->conn_req.link_selector = CAIF_LINK_HIGH_BANDW;
+	cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
 	cf_sk->conn_req.protocol = protocol;
 	/* Increase the number of sockets created. */
-	atomic_inc(&caif_nr_socks);
+	dbfs_atomic_inc(&cnt.caif_nr_socks);
+#ifdef CONFIG_DEBUG_FS
 	if (!IS_ERR(debugfsdir)) {
+		/* Fill in some information concerning the misc socket. */
+		snprintf(cf_sk->name, sizeof(cf_sk->name), "cfsk%d",
+				atomic_read(&cnt.caif_nr_socks));
+
 		cf_sk->debugfs_socket_dir =
 			debugfs_create_dir(cf_sk->name, debugfsdir);
-		debugfs_create_u32("conn_state", S_IRUSR | S_IWUSR,
-				cf_sk->debugfs_socket_dir, &cf_sk->conn_state);
+		debugfs_create_u32("sk_state", S_IRUSR | S_IWUSR,
+				cf_sk->debugfs_socket_dir,
+				(u32 *) &cf_sk->sk.sk_state);
 		debugfs_create_u32("flow_state", S_IRUSR | S_IWUSR,
 				cf_sk->debugfs_socket_dir, &cf_sk->flow_state);
-		debugfs_create_u32("read_queue_len", S_IRUSR | S_IWUSR,
+		debugfs_create_u32("sk_rmem_alloc", S_IRUSR | S_IWUSR,
+				cf_sk->debugfs_socket_dir,
+				(u32 *) &cf_sk->sk.sk_rmem_alloc);
+		debugfs_create_u32("sk_wmem_alloc", S_IRUSR | S_IWUSR,
 				cf_sk->debugfs_socket_dir,
-				(u32 *) &cf_sk->read_queue_len);
+				(u32 *) &cf_sk->sk.sk_wmem_alloc);
 		debugfs_create_u32("identity", S_IRUSR | S_IWUSR,
 				cf_sk->debugfs_socket_dir,
 				(u32 *) &cf_sk->layer.id);
 	}
+#endif
 	release_sock(&cf_sk->sk);
 	return 0;
-err_failed:
-	sk_free(sk);
-	return result;
 }
 
+
 static struct net_proto_family caif_family_ops = {
 	.family = PF_CAIF,
 	.create = caif_create,
 	.owner = THIS_MODULE,
 };
 
-static int af_caif_init(void)
+int af_caif_init(void)
 {
-	int err;
-	err = sock_register(&caif_family_ops);
-
+	int err = sock_register(&caif_family_ops);
 	if (!err)
 		return err;
-
 	return 0;
 }
 
 static int __init caif_sktinit_module(void)
 {
-	int stat;
 #ifdef CONFIG_DEBUG_FS
-	debugfsdir = debugfs_create_dir("chnl_skt", NULL);
+	debugfsdir = debugfs_create_dir("caif_sk", NULL);
 	if (!IS_ERR(debugfsdir)) {
-		debugfs_create_u32("skb_inuse", S_IRUSR | S_IWUSR,
-				debugfsdir,
-				(u32 *) &cnt.skb_in_use);
-		debugfs_create_u32("skb_alloc", S_IRUSR | S_IWUSR,
-				debugfsdir,
-				(u32 *) &cnt.skb_alloc);
-		debugfs_create_u32("skb_free", S_IRUSR | S_IWUSR,
-				debugfsdir,
-				(u32 *) &cnt.skb_free);
 		debugfs_create_u32("num_sockets", S_IRUSR | S_IWUSR,
 				debugfsdir,
-				(u32 *) &caif_nr_socks);
-		debugfs_create_u32("num_open", S_IRUSR | S_IWUSR,
+				(u32 *) &cnt.caif_nr_socks);
+		debugfs_create_u32("num_connect_req", S_IRUSR | S_IWUSR,
 				debugfsdir,
-				(u32 *) &cnt.num_open);
-		debugfs_create_u32("num_close", S_IRUSR | S_IWUSR,
+				(u32 *) &cnt.num_connect_req);
+		debugfs_create_u32("num_connect_resp", S_IRUSR | S_IWUSR,
 				debugfsdir,
-				(u32 *) &cnt.num_close);
-		debugfs_create_u32("num_init", S_IRUSR | S_IWUSR,
+				(u32 *) &cnt.num_connect_resp);
+		debugfs_create_u32("num_connect_fail_resp", S_IRUSR | S_IWUSR,
 				debugfsdir,
-				(u32 *) &cnt.num_init);
-		debugfs_create_u32("num_init_resp", S_IRUSR | S_IWUSR,
+				(u32 *) &cnt.num_connect_fail_resp);
+		debugfs_create_u32("num_disconnect", S_IRUSR | S_IWUSR,
 				debugfsdir,
-				(u32 *) &cnt.num_init_resp);
-		debugfs_create_u32("num_init_fail_resp", S_IRUSR | S_IWUSR,
-				debugfsdir,
-				(u32 *) &cnt.num_init_fail_resp);
-		debugfs_create_u32("num_deinit", S_IRUSR | S_IWUSR,
-				debugfsdir,
-				(u32 *) &cnt.num_deinit);
-		debugfs_create_u32("num_deinit_resp", S_IRUSR | S_IWUSR,
-				debugfsdir,
-				(u32 *) &cnt.num_deinit_resp);
+				(u32 *) &cnt.num_disconnect);
 		debugfs_create_u32("num_remote_shutdown_ind",
 				S_IRUSR | S_IWUSR, debugfsdir,
 				(u32 *) &cnt.num_remote_shutdown_ind);
@@ -1371,13 +1239,7 @@ static int __init caif_sktinit_module(void)
 				(u32 *) &cnt.num_rx_flow_on);
 	}
 #endif
-	stat = af_caif_init();
-	if (stat) {
-		pr_err("CAIF: %s(): Failed to initialize CAIF socket layer.",
-		       __func__);
-		return stat;
-	}
-	return 0;
+	return af_caif_init();
 }
 
 static void __exit caif_sktexit_module(void)
@@ -1386,6 +1248,5 @@ static void __exit caif_sktexit_module(void)
 	if (debugfsdir != NULL)
 		debugfs_remove_recursive(debugfsdir);
 }
-
 module_init(caif_sktinit_module);
 module_exit(caif_sktexit_module);