Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1958 commits)
  net: pack skb_shared_info more efficiently
  net_sched: red: split red_parms into parms and vars
  net_sched: sfq: extend limits
  cnic: Improve error recovery on bnx2x devices
  cnic: Re-init dev->stats_addr after chip reset
  net_sched: Bug in netem reordering
  bna: fix sparse warnings/errors
  bna: make ethtool_ops and strings const
  xgmac: cleanups
  net: make ethtool_ops const
  vmxnet3" make ethtool ops const
  xen-netback: make ops structs const
  virtio_net: Pass gfp flags when allocating rx buffers.
  ixgbe: FCoE: Add support for ndo_get_fcoe_hbainfo() call
  netdev: FCoE: Add new ndo_get_fcoe_hbainfo() call
  igb: reset PHY after recovering from PHY power down
  igb: add basic runtime PM support
  igb: Add support for byte queue limits.
  e1000: cleanup CE4100 MDIO registers access
  e1000: unmap ce4100_gbe_mdio_base_virt in e1000_remove
  ...

8 files changed, 454 insertions, 106 deletions

diff --git a/net/caif/Kconfig b/net/caif/Kconfig
index 529750da9624..936361e5a2b6 100644
--- a/net/caif/Kconfig
+++ b/net/caif/Kconfig
@@ -40,3 +40,14 @@ config CAIF_NETDEV
         If you select to build it as a built-in then the main CAIF device must
         also be a built-in.
         If unsure say Y.
+
+config CAIF_USB
+        tristate "CAIF USB support"
+        depends on CAIF
+        default n
+        ---help---
+        Say Y if you are using CAIF over USB CDC NCM.
+        This can be either built-in or a loadable module,
+        If you select to build it as a built-in then the main CAIF device must
+        also be a built-in.
+        If unsure say N.
diff --git a/net/caif/Makefile b/net/caif/Makefile
index ebcd4e7e6f47..cc2b51154d03 100644
--- a/net/caif/Makefile
+++ b/net/caif/Makefile
@@ -10,5 +10,6 @@ caif-y := caif_dev.o \
 obj-$(CONFIG_CAIF) += caif.o
 obj-$(CONFIG_CAIF_NETDEV) += chnl_net.o
 obj-$(CONFIG_CAIF) += caif_socket.o
+obj-$(CONFIG_CAIF_USB) += caif_usb.o
 
 export-y := caif.o
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index f1fa1f6e658d..b0ce14fbf6ef 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -17,6 +17,7 @@
 #include <linux/netdevice.h>
 #include <linux/mutex.h>
 #include <linux/module.h>
+#include <linux/spinlock.h>
 #include <net/netns/generic.h>
 #include <net/net_namespace.h>
 #include <net/pkt_sched.h>
@@ -24,6 +25,7 @@
 #include <net/caif/caif_layer.h>
 #include <net/caif/cfpkt.h>
 #include <net/caif/cfcnfg.h>
+#include <net/caif/cfserl.h>
 
 MODULE_LICENSE("GPL");
 
@@ -33,6 +35,10 @@ struct caif_device_entry {
         struct list_head list;
         struct net_device *netdev;
         int __percpu *pcpu_refcnt;
+        spinlock_t flow_lock;
+        struct sk_buff *xoff_skb;
+        void (*xoff_skb_dtor)(struct sk_buff *skb);
+        bool xoff;
 };
 
 struct caif_device_entry_list {
@@ -47,13 +53,14 @@ struct caif_net {
 };
 
 static int caif_net_id;
+static int q_high = 50; /* Percent */
 
 struct cfcnfg *get_cfcnfg(struct net *net)
 {
         struct caif_net *caifn;
-        BUG_ON(!net);
         caifn = net_generic(net, caif_net_id);
-        BUG_ON(!caifn);
+        if (!caifn)
+                return NULL;
         return caifn->cfg;
 }
 EXPORT_SYMBOL(get_cfcnfg);
@@ -61,9 +68,9 @@ EXPORT_SYMBOL(get_cfcnfg);
 static struct caif_device_entry_list *caif_device_list(struct net *net)
 {
         struct caif_net *caifn;
-        BUG_ON(!net);
         caifn = net_generic(net, caif_net_id);
-        BUG_ON(!caifn);
+        if (!caifn)
+                return NULL;
         return &caifn->caifdevs;
 }
 
@@ -92,7 +99,8 @@ static struct caif_device_entry *caif_device_alloc(struct net_device *dev)
         struct caif_device_entry *caifd;
 
         caifdevs = caif_device_list(dev_net(dev));
-        BUG_ON(!caifdevs);
+        if (!caifdevs)
+                return NULL;
 
         caifd = kzalloc(sizeof(*caifd), GFP_KERNEL);
         if (!caifd)
@@ -112,7 +120,9 @@ static struct caif_device_entry *caif_get(struct net_device *dev)
         struct caif_device_entry_list *caifdevs =
             caif_device_list(dev_net(dev));
         struct caif_device_entry *caifd;
-        BUG_ON(!caifdevs);
+        if (!caifdevs)
+                return NULL;
+
         list_for_each_entry_rcu(caifd, &caifdevs->list, list) {
                 if (caifd->netdev == dev)
                         return caifd;
@@ -120,15 +130,106 @@ static struct caif_device_entry *caif_get(struct net_device *dev)
         return NULL;
 }
 
+void caif_flow_cb(struct sk_buff *skb)
+{
+        struct caif_device_entry *caifd;
+        void (*dtor)(struct sk_buff *skb) = NULL;
+        bool send_xoff;
+
+        WARN_ON(skb->dev == NULL);
+
+        rcu_read_lock();
+        caifd = caif_get(skb->dev);
+        caifd_hold(caifd);
+        rcu_read_unlock();
+
+        spin_lock_bh(&caifd->flow_lock);
+        send_xoff = caifd->xoff;
+        caifd->xoff = 0;
+        if (!WARN_ON(caifd->xoff_skb_dtor == NULL)) {
+                WARN_ON(caifd->xoff_skb != skb);
+                dtor = caifd->xoff_skb_dtor;
+                caifd->xoff_skb = NULL;
+                caifd->xoff_skb_dtor = NULL;
+        }
+        spin_unlock_bh(&caifd->flow_lock);
+
+        if (dtor)
+                dtor(skb);
+
+        if (send_xoff)
+                caifd->layer.up->
+                        ctrlcmd(caifd->layer.up,
+                                _CAIF_CTRLCMD_PHYIF_FLOW_ON_IND,
+                                caifd->layer.id);
+        caifd_put(caifd);
+}
+
 static int transmit(struct cflayer *layer, struct cfpkt *pkt)
 {
-        int err;
+        int err, high = 0, qlen = 0;
+        struct caif_dev_common *caifdev;
         struct caif_device_entry *caifd =
             container_of(layer, struct caif_device_entry, layer);
         struct sk_buff *skb;
+        struct netdev_queue *txq;
+
+        rcu_read_lock_bh();
 
         skb = cfpkt_tonative(pkt);
         skb->dev = caifd->netdev;
+        skb_reset_network_header(skb);
+        skb->protocol = htons(ETH_P_CAIF);
+        caifdev = netdev_priv(caifd->netdev);
+
+        /* Check if we need to handle xoff */
+        if (likely(caifd->netdev->tx_queue_len == 0))
+                goto noxoff;
+
+        if (unlikely(caifd->xoff))
+                goto noxoff;
+
+        if (likely(!netif_queue_stopped(caifd->netdev))) {
+                /* If we run with a TX queue, check if the queue is too long*/
+                txq = netdev_get_tx_queue(skb->dev, 0);
+                qlen = qdisc_qlen(rcu_dereference_bh(txq->qdisc));
+
+                if (likely(qlen == 0))
+                        goto noxoff;
+
+                high = (caifd->netdev->tx_queue_len * q_high) / 100;
+                if (likely(qlen < high))
+                        goto noxoff;
+        }
+
+        /* Hold lock while accessing xoff */
+        spin_lock_bh(&caifd->flow_lock);
+        if (caifd->xoff) {
+                spin_unlock_bh(&caifd->flow_lock);
+                goto noxoff;
+        }
+
+        /*
+         * Handle flow off, we do this by temporary hi-jacking this
+         * skb's destructor function, and replace it with our own
+         * flow-on callback. The callback will set flow-on and call
+         * the original destructor.
+         */
+
+        pr_debug("queue has stopped(%d) or is full (%d > %d)\n",
+                        netif_queue_stopped(caifd->netdev),
+                        qlen, high);
+        caifd->xoff = 1;
+        caifd->xoff_skb = skb;
+        caifd->xoff_skb_dtor = skb->destructor;
+        skb->destructor = caif_flow_cb;
+        spin_unlock_bh(&caifd->flow_lock);
+
+        caifd->layer.up->ctrlcmd(caifd->layer.up,
+                                        _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND,
+                                        caifd->layer.id);
+noxoff:
+        rcu_read_unlock_bh();
 
         err = dev_queue_xmit(skb);
         if (err > 0)
@@ -172,7 +273,10 @@ static int receive(struct sk_buff *skb, struct net_device *dev,
 
         /* Release reference to stack upwards */
         caifd_put(caifd);
-        return 0;
+
+        if (err != 0)
+                err = NET_RX_DROP;
+        return err;
 }
 
 static struct packet_type caif_packet_type __read_mostly = {
@@ -203,6 +307,57 @@ static void dev_flowctrl(struct net_device *dev, int on)
         caifd_put(caifd);
 }
 
+void caif_enroll_dev(struct net_device *dev, struct caif_dev_common *caifdev,
+                        struct cflayer *link_support, int head_room,
+                        struct cflayer **layer, int (**rcv_func)(
+                                struct sk_buff *, struct net_device *,
+                                struct packet_type *, struct net_device *))
+{
+        struct caif_device_entry *caifd;
+        enum cfcnfg_phy_preference pref;
+        struct cfcnfg *cfg = get_cfcnfg(dev_net(dev));
+        struct caif_device_entry_list *caifdevs;
+
+        caifdevs = caif_device_list(dev_net(dev));
+        if (!cfg || !caifdevs)
+                return;
+        caifd = caif_device_alloc(dev);
+        if (!caifd)
+                return;
+        *layer = &caifd->layer;
+        spin_lock_init(&caifd->flow_lock);
+
+        switch (caifdev->link_select) {
+        case CAIF_LINK_HIGH_BANDW:
+                pref = CFPHYPREF_HIGH_BW;
+                break;
+        case CAIF_LINK_LOW_LATENCY:
+                pref = CFPHYPREF_LOW_LAT;
+                break;
+        default:
+                pref = CFPHYPREF_HIGH_BW;
+                break;
+        }
+        mutex_lock(&caifdevs->lock);
+        list_add_rcu(&caifd->list, &caifdevs->list);
+
+        strncpy(caifd->layer.name, dev->name,
+                sizeof(caifd->layer.name) - 1);
+        caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0;
+        caifd->layer.transmit = transmit;
+        cfcnfg_add_phy_layer(cfg,
+                                dev,
+                                &caifd->layer,
+                                pref,
+                                link_support,
+                                caifdev->use_fcs,
+                                head_room);
+        mutex_unlock(&caifdevs->lock);
+        if (rcv_func)
+                *rcv_func = receive;
+}
+EXPORT_SYMBOL(caif_enroll_dev);
+
 /* notify Caif of device events */
 static int caif_device_notify(struct notifier_block *me, unsigned long what,
                               void *arg)
@@ -210,62 +365,40 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
         struct net_device *dev = arg;
         struct caif_device_entry *caifd = NULL;
         struct caif_dev_common *caifdev;
-        enum cfcnfg_phy_preference pref;
-        enum cfcnfg_phy_type phy_type;
         struct cfcnfg *cfg;
+        struct cflayer *layer, *link_support;
+        int head_room = 0;
         struct caif_device_entry_list *caifdevs;
 
-        if (dev->type != ARPHRD_CAIF)
-                return 0;
-
         cfg = get_cfcnfg(dev_net(dev));
-        if (cfg == NULL)
+        caifdevs = caif_device_list(dev_net(dev));
+        if (!cfg || !caifdevs)
                 return 0;
 
-        caifdevs = caif_device_list(dev_net(dev));
+        caifd = caif_get(dev);
+        if (caifd == NULL && dev->type != ARPHRD_CAIF)
+                return 0;
 
         switch (what) {
         case NETDEV_REGISTER:
-                caifd = caif_device_alloc(dev);
-                if (!caifd)
-                        return 0;
+                if (caifd != NULL)
+                        break;
 
                 caifdev = netdev_priv(dev);
-                caifdev->flowctrl = dev_flowctrl;
 
-                caifd->layer.transmit = transmit;
-
-                if (caifdev->use_frag)
-                        phy_type = CFPHYTYPE_FRAG;
-                else
-                        phy_type = CFPHYTYPE_CAIF;
-
-                switch (caifdev->link_select) {
-                case CAIF_LINK_HIGH_BANDW:
-                        pref = CFPHYPREF_HIGH_BW;
-                        break;
-                case CAIF_LINK_LOW_LATENCY:
-                        pref = CFPHYPREF_LOW_LAT;
-                        break;
-                default:
-                        pref = CFPHYPREF_HIGH_BW;
-                        break;
+                link_support = NULL;
+                if (caifdev->use_frag) {
+                        head_room = 1;
+                        link_support = cfserl_create(dev->ifindex,
+                                                        caifdev->use_stx);
+                        if (!link_support) {
+                                pr_warn("Out of memory\n");
+                                break;
+                        }
                 }
-                strncpy(caifd->layer.name, dev->name,
-                        sizeof(caifd->layer.name) - 1);
-                caifd->layer.name[sizeof(caifd->layer.name) - 1] = 0;
-
-                mutex_lock(&caifdevs->lock);
-                list_add_rcu(&caifd->list, &caifdevs->list);
-
-                cfcnfg_add_phy_layer(cfg,
-                                     phy_type,
-                                     dev,
-                                     &caifd->layer,
-                                     pref,
-                                     caifdev->use_fcs,
-                                     caifdev->use_stx);
-                mutex_unlock(&caifdevs->lock);
+                caif_enroll_dev(dev, caifdev, link_support, head_room,
+                                &layer, NULL);
+                caifdev->flowctrl = dev_flowctrl;
                 break;
 
         case NETDEV_UP:
@@ -277,6 +410,7 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
                         break;
                 }
 
+                caifd->xoff = 0;
                 cfcnfg_set_phy_state(cfg, &caifd->layer, true);
                 rcu_read_unlock();
 
@@ -298,6 +432,24 @@ static int caif_device_notify(struct notifier_block *me, unsigned long what,
                 caifd->layer.up->ctrlcmd(caifd->layer.up,
                                          _CAIF_CTRLCMD_PHYIF_DOWN_IND,
                                          caifd->layer.id);
+
+                spin_lock_bh(&caifd->flow_lock);
+
+                /*
+                 * Replace our xoff-destructor with original destructor.
+                 * We trust that skb->destructor *always* is called before
+                 * the skb reference is invalid. The hijacked SKB destructor
+                 * takes the flow_lock so manipulating the skb->destructor here
+                 * should be safe.
+                */
+                if (caifd->xoff_skb_dtor != NULL && caifd->xoff_skb != NULL)
+                        caifd->xoff_skb->destructor = caifd->xoff_skb_dtor;
+
+                caifd->xoff = 0;
+                caifd->xoff_skb_dtor = NULL;
+                caifd->xoff_skb = NULL;
+
+                spin_unlock_bh(&caifd->flow_lock);
                 caifd_put(caifd);
                 break;
 
@@ -353,15 +505,15 @@ static struct notifier_block caif_device_notifier = {
 static int caif_init_net(struct net *net)
 {
         struct caif_net *caifn = net_generic(net, caif_net_id);
-        BUG_ON(!caifn);
+        if (WARN_ON(!caifn))
+                return -EINVAL;
+
         INIT_LIST_HEAD(&caifn->caifdevs.list);
         mutex_init(&caifn->caifdevs.lock);
 
         caifn->cfg = cfcnfg_create();
-        if (!caifn->cfg) {
-                pr_warn("can't create cfcnfg\n");
+        if (!caifn->cfg)
                 return -ENOMEM;
-        }
 
         return 0;
 }
@@ -371,17 +523,14 @@ static void caif_exit_net(struct net *net)
         struct caif_device_entry *caifd, *tmp;
         struct caif_device_entry_list *caifdevs =
             caif_device_list(net);
-        struct cfcnfg *cfg;
+        struct cfcnfg *cfg =  get_cfcnfg(net);
+
+        if (!cfg || !caifdevs)
+                return;
 
         rtnl_lock();
         mutex_lock(&caifdevs->lock);
 
-        cfg = get_cfcnfg(net);
-        if (cfg == NULL) {
-                mutex_unlock(&caifdevs->lock);
-                return;
-        }
-
         list_for_each_entry_safe(caifd, tmp, &caifdevs->list, list) {
                 int i = 0;
                 list_del_rcu(&caifd->list);
diff --git a/net/caif/caif_usb.c b/net/caif/caif_usb.c
new file mode 100644
index 000000000000..5fc9eca8cd41
--- /dev/null
+++ b/net/caif/caif_usb.c
@@ -0,0 +1,208 @@
+/*
+ * CAIF USB handler
+ * Copyright (C) ST-Ericsson AB 2011
+ * Author:      Sjur Brendeland/sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/usb/usbnet.h>
+#include <net/netns/generic.h>
+#include <net/caif/caif_dev.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/cfpkt.h>
+#include <net/caif/cfcnfg.h>
+
+MODULE_LICENSE("GPL");
+
+#define CFUSB_PAD_DESCR_SZ 1    /* Alignment descriptor length */
+#define CFUSB_ALIGNMENT 4       /* Number of bytes to align. */
+#define CFUSB_MAX_HEADLEN (CFUSB_PAD_DESCR_SZ + CFUSB_ALIGNMENT-1)
+#define STE_USB_VID 0x04cc      /* USB Product ID for ST-Ericsson */
+#define STE_USB_PID_CAIF 0x2306 /* Product id for CAIF Modems */
+
+struct cfusbl {
+        struct cflayer layer;
+        u8 tx_eth_hdr[ETH_HLEN];
+};
+
+static bool pack_added;
+
+static int cfusbl_receive(struct cflayer *layr, struct cfpkt *pkt)
+{
+        u8 hpad;
+
+        /* Remove padding. */
+        cfpkt_extr_head(pkt, &hpad, 1);
+        cfpkt_extr_head(pkt, NULL, hpad);
+        return layr->up->receive(layr->up, pkt);
+}
+
+static int cfusbl_transmit(struct cflayer *layr, struct cfpkt *pkt)
+{
+        struct caif_payload_info *info;
+        u8 hpad;
+        u8 zeros[CFUSB_ALIGNMENT];
+        struct sk_buff *skb;
+        struct cfusbl *usbl = container_of(layr, struct cfusbl, layer);
+
+        skb = cfpkt_tonative(pkt);
+
+        skb_reset_network_header(skb);
+        skb->protocol = htons(ETH_P_IP);
+
+        info = cfpkt_info(pkt);
+        hpad = (info->hdr_len + CFUSB_PAD_DESCR_SZ) & (CFUSB_ALIGNMENT - 1);
+
+        if (skb_headroom(skb) < ETH_HLEN + CFUSB_PAD_DESCR_SZ + hpad) {
+                pr_warn("Headroom to small\n");
+                kfree_skb(skb);
+                return -EIO;
+        }
+        memset(zeros, 0, hpad);
+
+        cfpkt_add_head(pkt, zeros, hpad);
+        cfpkt_add_head(pkt, &hpad, 1);
+        cfpkt_add_head(pkt, usbl->tx_eth_hdr, sizeof(usbl->tx_eth_hdr));
+        return layr->dn->transmit(layr->dn, pkt);
+}
+
+static void cfusbl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
+                                        int phyid)
+{
+        if (layr->up && layr->up->ctrlcmd)
+                layr->up->ctrlcmd(layr->up, ctrl, layr->id);
+}
+
+struct cflayer *cfusbl_create(int phyid, u8 ethaddr[ETH_ALEN],
+                                        u8 braddr[ETH_ALEN])
+{
+        struct cfusbl *this = kmalloc(sizeof(struct cfusbl), GFP_ATOMIC);
+
+        if (!this) {
+                pr_warn("Out of memory\n");
+                return NULL;
+        }
+        caif_assert(offsetof(struct cfusbl, layer) == 0);
+
+        memset(this, 0, sizeof(struct cflayer));
+        this->layer.receive = cfusbl_receive;
+        this->layer.transmit = cfusbl_transmit;
+        this->layer.ctrlcmd = cfusbl_ctrlcmd;
+        snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "usb%d", phyid);
+        this->layer.id = phyid;
+
+        /*
+         * Construct TX ethernet header:
+         *      0-5     destination address
+         *      5-11    source address
+         *      12-13   protocol type
+         */
+        memcpy(&this->tx_eth_hdr[ETH_ALEN], braddr, ETH_ALEN);
+        memcpy(&this->tx_eth_hdr[ETH_ALEN], ethaddr, ETH_ALEN);
+        this->tx_eth_hdr[12] = cpu_to_be16(ETH_P_802_EX1) & 0xff;
+        this->tx_eth_hdr[13] = (cpu_to_be16(ETH_P_802_EX1) >> 8) & 0xff;
+        pr_debug("caif ethernet TX-header dst:%pM src:%pM type:%02x%02x\n",
+                        this->tx_eth_hdr, this->tx_eth_hdr + ETH_ALEN,
+                        this->tx_eth_hdr[12], this->tx_eth_hdr[13]);
+
+        return (struct cflayer *) this;
+}
+
+static struct packet_type caif_usb_type __read_mostly = {
+        .type = cpu_to_be16(ETH_P_802_EX1),
+};
+
+static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
+                              void *arg)
+{
+        struct net_device *dev = arg;
+        struct caif_dev_common common;
+        struct cflayer *layer, *link_support;
+        struct usbnet   *usbnet = netdev_priv(dev);
+        struct usb_device       *usbdev = usbnet->udev;
+        struct ethtool_drvinfo drvinfo;
+
+        /*
+         * Quirks: High-jack ethtool to find if we have a NCM device,
+         * and find it's VID/PID.
+         */
+        if (dev->ethtool_ops == NULL || dev->ethtool_ops->get_drvinfo == NULL)
+                return 0;
+
+        dev->ethtool_ops->get_drvinfo(dev, &drvinfo);
+        if (strncmp(drvinfo.driver, "cdc_ncm", 7) != 0)
+                return 0;
+
+        pr_debug("USB CDC NCM device VID:0x%4x PID:0x%4x\n",
+                le16_to_cpu(usbdev->descriptor.idVendor),
+                le16_to_cpu(usbdev->descriptor.idProduct));
+
+        /* Check for VID/PID that supports CAIF */
+        if (!(le16_to_cpu(usbdev->descriptor.idVendor) == STE_USB_VID &&
+                le16_to_cpu(usbdev->descriptor.idProduct) == STE_USB_PID_CAIF))
+                return 0;
+
+        if (what == NETDEV_UNREGISTER)
+                module_put(THIS_MODULE);
+
+        if (what != NETDEV_REGISTER)
+                return 0;
+
+        __module_get(THIS_MODULE);
+
+        memset(&common, 0, sizeof(common));
+        common.use_frag = false;
+        common.use_fcs = false;
+        common.use_stx = false;
+        common.link_select = CAIF_LINK_HIGH_BANDW;
+        common.flowctrl = NULL;
+
+        link_support = cfusbl_create(dev->ifindex, dev->dev_addr,
+                                        dev->broadcast);
+
+        if (!link_support)
+                return -ENOMEM;
+
+        if (dev->num_tx_queues > 1)
+                pr_warn("USB device uses more than one tx queue\n");
+
+        caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN,
+                        &layer, &caif_usb_type.func);
+        if (!pack_added)
+                dev_add_pack(&caif_usb_type);
+        pack_added = true;
+
+        strncpy(layer->name, dev->name,
+                        sizeof(layer->name) - 1);
+        layer->name[sizeof(layer->name) - 1] = 0;
+
+        return 0;
+}
+
+static struct notifier_block caif_device_notifier = {
+        .notifier_call = cfusbl_device_notify,
+        .priority = 0,
+};
+
+static int __init cfusbl_init(void)
+{
+        return register_netdevice_notifier(&caif_device_notifier);
+}
+
+static void __exit cfusbl_exit(void)
+{
+        unregister_netdevice_notifier(&caif_device_notifier);
+        dev_remove_pack(&caif_usb_type);
+}
+
+module_init(cfusbl_init);
+module_exit(cfusbl_exit);
diff --git a/net/caif/cfcnfg.c b/net/caif/cfcnfg.c
index 00523ecc4ced..598aafb4cb51 100644
--- a/net/caif/cfcnfg.c
+++ b/net/caif/cfcnfg.c
@@ -45,8 +45,8 @@ struct cfcnfg_phyinfo {
         /* Interface index */
         int ifindex;
 
-        /* Use Start of frame extension */
-        bool use_stx;
+        /* Protocol head room added for CAIF link layer */
+        int head_room;
 
         /* Use Start of frame checksum */
         bool use_fcs;
@@ -187,11 +187,11 @@ int caif_disconnect_client(struct net *net, struct cflayer *adap_layer)
         if (channel_id != 0) {
                 struct cflayer *servl;
                 servl = cfmuxl_remove_uplayer(cfg->mux, channel_id);
+                cfctrl_linkdown_req(cfg->ctrl, channel_id, adap_layer);
                 if (servl != NULL)
                         layer_set_up(servl, NULL);
         } else
                 pr_debug("nothing to disconnect\n");
-        cfctrl_linkdown_req(cfg->ctrl, channel_id, adap_layer);
 
         /* Do RCU sync before initiating cleanup */
         synchronize_rcu();
@@ -350,9 +350,7 @@ int caif_connect_client(struct net *net, struct caif_connect_request *conn_req,
 
         *ifindex = phy->ifindex;
         *proto_tail = 2;
-        *proto_head =
-
-        protohead[param.linktype] + (phy->use_stx ? 1 : 0);
+        *proto_head = protohead[param.linktype] + phy->head_room;
 
         rcu_read_unlock();
 
@@ -460,13 +458,13 @@ unlock:
 }
 
 void
-cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type,
+cfcnfg_add_phy_layer(struct cfcnfg *cnfg,
                      struct net_device *dev, struct cflayer *phy_layer,
                      enum cfcnfg_phy_preference pref,
-                     bool fcs, bool stx)
+                     struct cflayer *link_support,
+                     bool fcs, int head_room)
 {
         struct cflayer *frml;
-        struct cflayer *phy_driver = NULL;
         struct cfcnfg_phyinfo *phyinfo = NULL;
         int i;
         u8 phyid;
@@ -482,26 +480,13 @@ cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type,
                         goto got_phyid;
         }
         pr_warn("Too many CAIF Link Layers (max 6)\n");
-        goto out_err;
+        goto out;
 
 got_phyid:
         phyinfo = kzalloc(sizeof(struct cfcnfg_phyinfo), GFP_ATOMIC);
         if (!phyinfo)
                 goto out_err;
 
-        switch (phy_type) {
-        case CFPHYTYPE_FRAG:
-                phy_driver =
-                    cfserl_create(CFPHYTYPE_FRAG, phyid, stx);
-                if (!phy_driver)
-                        goto out_err;
-                break;
-        case CFPHYTYPE_CAIF:
-                phy_driver = NULL;
-                break;
-        default:
-                goto out_err;
-        }
         phy_layer->id = phyid;
         phyinfo->pref = pref;
         phyinfo->id = phyid;
@@ -509,7 +494,7 @@ got_phyid:
         phyinfo->dev_info.dev = dev;
         phyinfo->phy_layer = phy_layer;
         phyinfo->ifindex = dev->ifindex;
-        phyinfo->use_stx = stx;
+        phyinfo->head_room = head_room;
         phyinfo->use_fcs = fcs;
 
         frml = cffrml_create(phyid, fcs);
@@ -519,23 +504,23 @@ got_phyid:
         phyinfo->frm_layer = frml;
         layer_set_up(frml, cnfg->mux);
 
-        if (phy_driver != NULL) {
-                phy_driver->id = phyid;
-                layer_set_dn(frml, phy_driver);
-                layer_set_up(phy_driver, frml);
-                layer_set_dn(phy_driver, phy_layer);
-                layer_set_up(phy_layer, phy_driver);
+        if (link_support != NULL) {
+                link_support->id = phyid;
+                layer_set_dn(frml, link_support);
+                layer_set_up(link_support, frml);
+                layer_set_dn(link_support, phy_layer);
+                layer_set_up(phy_layer, link_support);
         } else {
                 layer_set_dn(frml, phy_layer);
                 layer_set_up(phy_layer, frml);
         }
 
         list_add_rcu(&phyinfo->node, &cnfg->phys);
+out:
         mutex_unlock(&cnfg->lock);
         return;
 
 out_err:
-        kfree(phy_driver);
         kfree(phyinfo);
         mutex_unlock(&cnfg->lock);
 }
diff --git a/net/caif/cfpkt_skbuff.c b/net/caif/cfpkt_skbuff.c
index df08c47183d4..e335ba859b97 100644
--- a/net/caif/cfpkt_skbuff.c
+++ b/net/caif/cfpkt_skbuff.c
@@ -63,7 +63,6 @@ static inline struct cfpkt *skb_to_pkt(struct sk_buff *skb)
         return (struct cfpkt *) skb;
 }
 
-
 struct cfpkt *cfpkt_fromnative(enum caif_direction dir, void *nativepkt)
 {
         struct cfpkt *pkt = skb_to_pkt(nativepkt);
@@ -105,14 +104,12 @@ void cfpkt_destroy(struct cfpkt *pkt)
         kfree_skb(skb);
 }
 
-
 inline bool cfpkt_more(struct cfpkt *pkt)
 {
         struct sk_buff *skb = pkt_to_skb(pkt);
         return skb->len > 0;
 }
 
-
 int cfpkt_peek_head(struct cfpkt *pkt, void *data, u16 len)
 {
         struct sk_buff *skb = pkt_to_skb(pkt);
@@ -144,9 +141,11 @@ int cfpkt_extr_head(struct cfpkt *pkt, void *data, u16 len)
         }
         from = skb_pull(skb, len);
         from -= len;
-        memcpy(data, from, len);
+        if (data)
+                memcpy(data, from, len);
         return 0;
 }
+EXPORT_SYMBOL(cfpkt_extr_head);
 
 int cfpkt_extr_trail(struct cfpkt *pkt, void *dta, u16 len)
 {
@@ -170,13 +169,11 @@ int cfpkt_extr_trail(struct cfpkt *pkt, void *dta, u16 len)
         return 0;
 }
 
-
 int cfpkt_pad_trail(struct cfpkt *pkt, u16 len)
 {
         return cfpkt_add_body(pkt, NULL, len);
 }
 
-
 int cfpkt_add_body(struct cfpkt *pkt, const void *data, u16 len)
 {
         struct sk_buff *skb = pkt_to_skb(pkt);
@@ -255,21 +252,19 @@ int cfpkt_add_head(struct cfpkt *pkt, const void *data2, u16 len)
         memcpy(to, data, len);
         return 0;
 }
-
+EXPORT_SYMBOL(cfpkt_add_head);
 
 inline int cfpkt_add_trail(struct cfpkt *pkt, const void *data, u16 len)
 {
         return cfpkt_add_body(pkt, data, len);
 }
 
-
 inline u16 cfpkt_getlen(struct cfpkt *pkt)
 {
         struct sk_buff *skb = pkt_to_skb(pkt);
         return skb->len;
 }
 
-
 inline u16 cfpkt_iterate(struct cfpkt *pkt,
                             u16 (*iter_func)(u16, void *, u16),
                             u16 data)
@@ -287,7 +282,6 @@ inline u16 cfpkt_iterate(struct cfpkt *pkt,
         return iter_func(data, pkt->skb.data, cfpkt_getlen(pkt));
 }
 
-
 int cfpkt_setlen(struct cfpkt *pkt, u16 len)
 {
         struct sk_buff *skb = pkt_to_skb(pkt);
@@ -399,3 +393,4 @@ struct caif_payload_info *cfpkt_info(struct cfpkt *pkt)
 {
         return (struct caif_payload_info *)&pkt_to_skb(pkt)->cb;
 }
+EXPORT_SYMBOL(cfpkt_info);
diff --git a/net/caif/cfrfml.c b/net/caif/cfrfml.c
index 81660f809713..6dc75d4f8d94 100644
--- a/net/caif/cfrfml.c
+++ b/net/caif/cfrfml.c
@@ -190,7 +190,7 @@ out:
 
 static int cfrfml_transmit_segment(struct cfrfml *rfml, struct cfpkt *pkt)
 {
-        caif_assert(cfpkt_getlen(pkt) < rfml->fragment_size);
+        caif_assert(cfpkt_getlen(pkt) < rfml->fragment_size + RFM_HEAD_SIZE);
 
         /* Add info for MUX-layer to route the packet out. */
         cfpkt_info(pkt)->channel_id = rfml->serv.layer.id;
diff --git a/net/caif/cfserl.c b/net/caif/cfserl.c
index 797c8d165993..8e68b97f13ee 100644
--- a/net/caif/cfserl.c
+++ b/net/caif/cfserl.c
@@ -31,7 +31,7 @@ static int cfserl_transmit(struct cflayer *layr, struct cfpkt *pkt);
 static void cfserl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
                                 int phyid);
 
-struct cflayer *cfserl_create(int type, int instance, bool use_stx)
+struct cflayer *cfserl_create(int instance, bool use_stx)
 {
         struct cfserl *this = kzalloc(sizeof(struct cfserl), GFP_ATOMIC);
         if (!this)
@@ -40,7 +40,6 @@ struct cflayer *cfserl_create(int type, int instance, bool use_stx)
         this->layer.receive = cfserl_receive;
         this->layer.transmit = cfserl_transmit;
         this->layer.ctrlcmd = cfserl_ctrlcmd;
-        this->layer.type = type;
         this->usestx = use_stx;
         spin_lock_init(&this->sync);
         snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "ser1");