uwb: add the WiMedia LLC Protocol stack

Add the generic code for the WiMedia Logical Link Control Protocol (WLP).

This has been split into several patches for easier review.

core (this patch):
  - everything else

messages:
  - WLP message construction/decode

wss:
  - Wireless Service Set support

build-system:
  - Kconfig and Kbuild files
Signed-off-by: NDavid Vrabel <david.vrabel@csr.com>

drivers/uwb/wlp/driver.c

+/*
+ * WiMedia Logical Link Control Protocol (WLP)
+ *
+ * Copyright (C) 2007 Intel Corporation
+ * Reinette Chatre <reinette.chatre@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * Life cycle of WLP substack
+ *
+ * FIXME: Docs
+ */
+
+#include <linux/module.h>
+
+static int __init wlp_subsys_init(void)
+{
+	return 0;
+}
+module_init(wlp_subsys_init);
+
+static void __exit wlp_subsys_exit(void)
+{
+	return;
+}
+module_exit(wlp_subsys_exit);
+
+MODULE_AUTHOR("Reinette Chatre <reinette.chatre@intel.com>");
+MODULE_DESCRIPTION("WiMedia Logical Link Control Protocol (WLP)");
+MODULE_LICENSE("GPL");

drivers/uwb/wlp/eda.c

+/*
+ * WUSB Wire Adapter: WLP interface
+ * Ethernet to device address cache
+ *
+ * Copyright (C) 2005-2006 Intel Corporation
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * We need to be able to map ethernet addresses to device addresses
+ * and back because there is not explicit relationship between the eth
+ * addresses used in the ETH frames and the device addresses (no, it
+ * would not have been simpler to force as ETH address the MBOA MAC
+ * address...no, not at all :).
+ *
+ * A device has one MBOA MAC address and one device address. It is possible
+ * for a device to have more than one virtual MAC address (although a
+ * virtual address can be the same as the MBOA MAC address). The device
+ * address is guaranteed to be unique among the devices in the extended
+ * beacon group (see ECMA 17.1.1). We thus use the device address as index
+ * to this cache. We do allow searching based on virtual address as this
+ * is how Ethernet frames will be addressed.
+ *
+ * We need to support virtual EUI-48. Although, right now the virtual
+ * EUI-48 will always be the same as the MAC SAP address. The EDA cache
+ * entry thus contains a MAC SAP address as well as the virtual address
+ * (used to map the network stack address to a neighbor). When we move
+ * to support more than one virtual MAC on a host then this organization
+ * will have to change. Perhaps a neighbor has a list of WSSs, each with a
+ * tag and virtual EUI-48.
+ *
+ * On data transmission
+ * it is used to determine if the neighbor is connected and what WSS it
+ * belongs to. With this we know what tag to add to the WLP frame. Storing
+ * the WSS in the EDA cache may be overkill because we only support one
+ * WSS. Hopefully we will support more than one WSS at some point.
+ * On data reception it is used to determine the WSS based on
+ * the tag and address of the transmitting neighbor.
+ */
+
+#define D_LOCAL 5
+#include <linux/netdevice.h>
+#include <linux/uwb/debug.h>
+#include <linux/etherdevice.h>
+#include <linux/wlp.h>
+#include "wlp-internal.h"
+
+
+/* FIXME: cache is not purged, only on device close */
+
+/* FIXME: does not scale, change to dynamic array */
+
+/*
+ * Initialize the EDA cache
+ *
+ * @returns 0 if ok, < 0 errno code on error
+ *
+ * Call when the interface is being brought up
+ *
+ * NOTE: Keep it as a separate function as the implementation will
+ *       change and be more complex.
+ */
+void wlp_eda_init(struct wlp_eda *eda)
+{
+	INIT_LIST_HEAD(&eda->cache);
+	spin_lock_init(&eda->lock);
+}
+
+/*
+ * Release the EDA cache
+ *
+ * @returns 0 if ok, < 0 errno code on error
+ *
+ * Called when the interface is brought down
+ */
+void wlp_eda_release(struct wlp_eda *eda)
+{
+	unsigned long flags;
+	struct wlp_eda_node *itr, *next;
+
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry_safe(itr, next, &eda->cache, list_node) {
+		list_del(&itr->list_node);
+		kfree(itr);
+	}
+	spin_unlock_irqrestore(&eda->lock, flags);
+}
+
+/*
+ * Add an address mapping
+ *
+ * @returns 0 if ok, < 0 errno code on error
+ *
+ * An address mapping is initially created when the neighbor device is seen
+ * for the first time (it is "onair"). At this time the neighbor is not
+ * connected or associated with a WSS so we only populate the Ethernet and
+ * Device address fields.
+ *
+ */
+int wlp_eda_create_node(struct wlp_eda *eda,
+			const unsigned char eth_addr[ETH_ALEN],
+			const struct uwb_dev_addr *dev_addr)
+{
+	int result = 0;
+	struct wlp_eda_node *itr;
+	unsigned long flags;
+
+	BUG_ON(dev_addr == NULL || eth_addr == NULL);
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry(itr, &eda->cache, list_node) {
+		if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
+			printk(KERN_ERR "EDA cache already contains entry "
+			       "for neighbor %02x:%02x\n",
+			       dev_addr->data[1], dev_addr->data[0]);
+			result = -EEXIST;
+			goto out_unlock;
+		}
+	}
+	itr = kzalloc(sizeof(*itr), GFP_ATOMIC);
+	if (itr != NULL) {
+		memcpy(itr->eth_addr, eth_addr, sizeof(itr->eth_addr));
+		itr->dev_addr = *dev_addr;
+		list_add(&itr->list_node, &eda->cache);
+	} else
+		result = -ENOMEM;
+out_unlock:
+	spin_unlock_irqrestore(&eda->lock, flags);
+	return result;
+}
+
+/*
+ * Remove entry from EDA cache
+ *
+ * This is done when the device goes off air.
+ */
+void wlp_eda_rm_node(struct wlp_eda *eda, const struct uwb_dev_addr *dev_addr)
+{
+	struct wlp_eda_node *itr, *next;
+	unsigned long flags;
+
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry_safe(itr, next, &eda->cache, list_node) {
+		if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
+			list_del(&itr->list_node);
+			kfree(itr);
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&eda->lock, flags);
+}
+
+/*
+ * Update an address mapping
+ *
+ * @returns 0 if ok, < 0 errno code on error
+ */
+int wlp_eda_update_node(struct wlp_eda *eda,
+			const struct uwb_dev_addr *dev_addr,
+			struct wlp_wss *wss,
+			const unsigned char virt_addr[ETH_ALEN],
+			const u8 tag, const enum wlp_wss_connect state)
+{
+	int result = -ENOENT;
+	struct wlp_eda_node *itr;
+	unsigned long flags;
+
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry(itr, &eda->cache, list_node) {
+		if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
+			/* Found it, update it */
+			itr->wss = wss;
+			memcpy(itr->virt_addr, virt_addr,
+			       sizeof(itr->virt_addr));
+			itr->tag = tag;
+			itr->state = state;
+			result = 0;
+			goto out_unlock;
+		}
+	}
+	/* Not found */
+out_unlock:
+	spin_unlock_irqrestore(&eda->lock, flags);
+	return result;
+}
+
+/*
+ * Update only state field of an address mapping
+ *
+ * @returns 0 if ok, < 0 errno code on error
+ */
+int wlp_eda_update_node_state(struct wlp_eda *eda,
+			      const struct uwb_dev_addr *dev_addr,
+			      const enum wlp_wss_connect state)
+{
+	int result = -ENOENT;
+	struct wlp_eda_node *itr;
+	unsigned long flags;
+
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry(itr, &eda->cache, list_node) {
+		if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
+			/* Found it, update it */
+			itr->state = state;
+			result = 0;
+			goto out_unlock;
+		}
+	}
+	/* Not found */
+out_unlock:
+	spin_unlock_irqrestore(&eda->lock, flags);
+	return result;
+}
+
+/*
+ * Return contents of EDA cache entry
+ *
+ * @dev_addr: index to EDA cache
+ * @eda_entry: pointer to where contents of EDA cache will be copied
+ */
+int wlp_copy_eda_node(struct wlp_eda *eda, struct uwb_dev_addr *dev_addr,
+		      struct wlp_eda_node *eda_entry)
+{
+	int result = -ENOENT;
+	struct wlp_eda_node *itr;
+	unsigned long flags;
+
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry(itr, &eda->cache, list_node) {
+		if (!memcmp(&itr->dev_addr, dev_addr, sizeof(itr->dev_addr))) {
+			*eda_entry = *itr;
+			result = 0;
+			goto out_unlock;
+		}
+	}
+	/* Not found */
+out_unlock:
+	spin_unlock_irqrestore(&eda->lock, flags);
+	return result;
+}
+
+/*
+ * Execute function for every element in the cache
+ *
+ * @function: function to execute on element of cache (must be atomic)
+ * @priv:     private data of function
+ * @returns:  result of first function that failed, or last function
+ *            executed if no function failed.
+ *
+ * Stop executing when function returns error for any element in cache.
+ *
+ * IMPORTANT: We are using a spinlock here: the function executed on each
+ * element has to be atomic.
+ */
+int wlp_eda_for_each(struct wlp_eda *eda, wlp_eda_for_each_f function,
+		     void *priv)
+{
+	int result = 0;
+	struct wlp *wlp = container_of(eda, struct wlp, eda);
+	struct wlp_eda_node *entry;
+	unsigned long flags;
+
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry(entry, &eda->cache, list_node) {
+		result = (*function)(wlp, entry, priv);
+		if (result < 0)
+			break;
+	}
+	spin_unlock_irqrestore(&eda->lock, flags);
+	return result;
+}
+
+/*
+ * Execute function for single element in the cache (return dev addr)
+ *
+ * @virt_addr: index into EDA cache used to determine which element to
+ *             execute the function on
+ * @dev_addr: device address of element in cache will be returned using
+ *            @dev_addr
+ * @function: function to execute on element of cache (must be atomic)
+ * @priv:     private data of function
+ * @returns:  result of function
+ *
+ * IMPORTANT: We are using a spinlock here: the function executed on the
+ * element has to be atomic.
+ */
+int wlp_eda_for_virtual(struct wlp_eda *eda,
+			const unsigned char virt_addr[ETH_ALEN],
+			struct uwb_dev_addr *dev_addr,
+			wlp_eda_for_each_f function,
+			void *priv)
+{
+	int result = 0;
+	struct wlp *wlp = container_of(eda, struct wlp, eda);
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	struct wlp_eda_node *itr;
+	unsigned long flags;
+	int found = 0;
+
+	spin_lock_irqsave(&eda->lock, flags);
+	list_for_each_entry(itr, &eda->cache, list_node) {
+		if (!memcmp(itr->virt_addr, virt_addr,
+			   sizeof(itr->virt_addr))) {
+			d_printf(6, dev, "EDA: looking for "
+			       "%02x:%02x:%02x:%02x:%02x:%02x hit %02x:%02x "
+			       "wss %p tag 0x%02x state %u\n",
+			       virt_addr[0], virt_addr[1],
+			       virt_addr[2], virt_addr[3],
+			       virt_addr[4], virt_addr[5],
+			       itr->dev_addr.data[1],
+			       itr->dev_addr.data[0], itr->wss,
+			       itr->tag, itr->state);
+			result = (*function)(wlp, itr, priv);
+			*dev_addr = itr->dev_addr;
+			found = 1;
+			break;
+		} else
+			d_printf(6, dev, "EDA: looking for "
+			       "%02x:%02x:%02x:%02x:%02x:%02x "
+			       "against "
+			       "%02x:%02x:%02x:%02x:%02x:%02x miss\n",
+			       virt_addr[0], virt_addr[1],
+			       virt_addr[2], virt_addr[3],
+			       virt_addr[4], virt_addr[5],
+			       itr->virt_addr[0], itr->virt_addr[1],
+			       itr->virt_addr[2], itr->virt_addr[3],
+			       itr->virt_addr[4], itr->virt_addr[5]);
+	}
+	if (!found) {
+		if (printk_ratelimit())
+			dev_err(dev, "EDA: Eth addr %02x:%02x:%02x"
+				":%02x:%02x:%02x not found.\n",
+				virt_addr[0], virt_addr[1],
+				virt_addr[2], virt_addr[3],
+				virt_addr[4], virt_addr[5]);
+		result = -ENODEV;
+	}
+	spin_unlock_irqrestore(&eda->lock, flags);
+	return result;
+}
+
+static const char *__wlp_wss_connect_state[] = { "WLP_WSS_UNCONNECTED",
+					  "WLP_WSS_CONNECTED",
+					  "WLP_WSS_CONNECT_FAILED",
+};
+
+static const char *wlp_wss_connect_state_str(unsigned id)
+{
+	if (id >= ARRAY_SIZE(__wlp_wss_connect_state))
+		return "unknown WSS connection state";
+	return __wlp_wss_connect_state[id];
+}
+
+/*
+ * View EDA cache from user space
+ *
+ * A debugging feature to give user visibility into the EDA cache. Also
+ * used to display members of WSS to user (called from wlp_wss_members_show())
+ */
+ssize_t wlp_eda_show(struct wlp *wlp, char *buf)
+{
+	ssize_t result = 0;
+	struct wlp_eda_node *entry;
+	unsigned long flags;
+	struct wlp_eda *eda = &wlp->eda;
+	spin_lock_irqsave(&eda->lock, flags);
+	result = scnprintf(buf, PAGE_SIZE, "#eth_addr dev_addr wss_ptr "
+			   "tag state virt_addr\n");
+	list_for_each_entry(entry, &eda->cache, list_node) {
+		result += scnprintf(buf + result, PAGE_SIZE - result,
+				    "%02x:%02x:%02x:%02x:%02x:%02x %02x:%02x "
+				    "%p 0x%02x %s "
+				    "%02x:%02x:%02x:%02x:%02x:%02x\n",
+				    entry->eth_addr[0], entry->eth_addr[1],
+				    entry->eth_addr[2], entry->eth_addr[3],
+				    entry->eth_addr[4], entry->eth_addr[5],
+				    entry->dev_addr.data[1],
+				    entry->dev_addr.data[0], entry->wss,
+				    entry->tag,
+				    wlp_wss_connect_state_str(entry->state),
+				    entry->virt_addr[0], entry->virt_addr[1],
+				    entry->virt_addr[2], entry->virt_addr[3],
+				    entry->virt_addr[4], entry->virt_addr[5]);
+		if (result >= PAGE_SIZE)
+			break;
+	}
+	spin_unlock_irqrestore(&eda->lock, flags);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_eda_show);
+
+/*
+ * Add new EDA cache entry based on user input in sysfs
+ *
+ * Should only be used for debugging.
+ *
+ * The WSS is assumed to be the only WSS supported. This needs to be
+ * redesigned when we support more than one WSS.
+ */
+ssize_t wlp_eda_store(struct wlp *wlp, const char *buf, size_t size)
+{
+	ssize_t result;
+	struct wlp_eda *eda = &wlp->eda;
+	u8 eth_addr[6];
+	struct uwb_dev_addr dev_addr;
+	u8 tag;
+	unsigned state;
+
+	result = sscanf(buf, "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx "
+			"%02hhx:%02hhx %02hhx %u\n",
+			&eth_addr[0], &eth_addr[1],
+			&eth_addr[2], &eth_addr[3],
+			&eth_addr[4], &eth_addr[5],
+			&dev_addr.data[1], &dev_addr.data[0], &tag, &state);
+	switch (result) {
+	case 6: /* no dev addr specified -- remove entry NOT IMPLEMENTED */
+		/*result = wlp_eda_rm(eda, eth_addr, &dev_addr);*/
+		result = -ENOSYS;
+		break;
+	case 10:
+		state = state >= 1 ? 1 : 0;
+		result = wlp_eda_create_node(eda, eth_addr, &dev_addr);
+		if (result < 0 && result != -EEXIST)
+			goto error;
+		/* Set virtual addr to be same as MAC */
+		result = wlp_eda_update_node(eda, &dev_addr, &wlp->wss,
+					     eth_addr, tag, state);
+		if (result < 0)
+			goto error;
+		break;
+	default: /* bad format */
+		result = -EINVAL;
+	}
+error:
+	return result < 0 ? result : size;
+}
+EXPORT_SYMBOL_GPL(wlp_eda_store);

drivers/uwb/wlp/sysfs.c

+/*
+ * WiMedia Logical Link Control Protocol (WLP)
+ * sysfs functions
+ *
+ * Copyright (C) 2007 Intel Corporation
+ * Reinette Chatre <reinette.chatre@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * FIXME: Docs
+ *
+ */
+
+#include <linux/wlp.h>
+#include "wlp-internal.h"
+
+static
+size_t wlp_wss_wssid_e_print(char *buf, size_t bufsize,
+			     struct wlp_wssid_e *wssid_e)
+{
+	size_t used = 0;
+	used += scnprintf(buf, bufsize, " WSS: ");
+	used += wlp_wss_uuid_print(buf + used, bufsize - used,
+				   &wssid_e->wssid);
+
+	if (wssid_e->info != NULL) {
+		used += scnprintf(buf + used, bufsize - used, " ");
+		used += uwb_mac_addr_print(buf + used, bufsize - used,
+					   &wssid_e->info->bcast);
+		used += scnprintf(buf + used, bufsize - used, " %u %u %s\n",
+				  wssid_e->info->accept_enroll,
+				  wssid_e->info->sec_status,
+				  wssid_e->info->name);
+	}
+	return used;
+}
+
+/**
+ * Print out information learned from neighbor discovery
+ *
+ * Some fields being printed may not be included in the device discovery
+ * information (it is not mandatory). We are thus careful how the
+ * information is printed to ensure it is clear to the user what field is
+ * being referenced.
+ * The information being printed is for one time use - temporary storage is
+ * cleaned after it is printed.
+ *
+ * Ideally sysfs output should be on one line. The information printed here
+ * contain a few strings so it will be hard to parse if they are all
+ * printed on the same line - without agreeing on a standard field
+ * separator.
+ */
+static
+ssize_t wlp_wss_neighborhood_print_remove(struct wlp *wlp, char *buf,
+				   size_t bufsize)
+{
+	size_t used = 0;
+	struct wlp_neighbor_e *neighb;
+	struct wlp_wssid_e *wssid_e;
+
+	mutex_lock(&wlp->nbmutex);
+	used = scnprintf(buf, bufsize, "#Neighbor information\n"
+			 "#uuid dev_addr\n"
+			 "# Device Name:\n# Model Name:\n# Manufacturer:\n"
+			 "# Model Nr:\n# Serial:\n"
+			 "# Pri Dev type: CategoryID OUI OUISubdiv "
+			 "SubcategoryID\n"
+			 "# WSS: WSSID WSS_name accept_enroll sec_status "
+			 "bcast\n"
+			 "# WSS: WSSID WSS_name accept_enroll sec_status "
+			 "bcast\n\n");
+	list_for_each_entry(neighb, &wlp->neighbors, node) {
+		if (bufsize - used <= 0)
+			goto out;
+		used += wlp_wss_uuid_print(buf + used, bufsize - used,
+					   &neighb->uuid);
+		buf[used++] = ' ';
+		used += uwb_dev_addr_print(buf + used, bufsize - used,
+					   &neighb->uwb_dev->dev_addr);
+		if (neighb->info != NULL)
+			used += scnprintf(buf + used, bufsize - used,
+					  "\n Device Name: %s\n"
+					  " Model Name: %s\n"
+					  " Manufacturer:%s \n"
+					  " Model Nr: %s\n"
+					  " Serial: %s\n"
+					  " Pri Dev type: "
+					  "%u %02x:%02x:%02x %u %u\n",
+					  neighb->info->name,
+					  neighb->info->model_name,
+					  neighb->info->manufacturer,
+					  neighb->info->model_nr,
+					  neighb->info->serial,
+					  neighb->info->prim_dev_type.category,
+					  neighb->info->prim_dev_type.OUI[0],
+					  neighb->info->prim_dev_type.OUI[1],
+					  neighb->info->prim_dev_type.OUI[2],
+					  neighb->info->prim_dev_type.OUIsubdiv,
+					  neighb->info->prim_dev_type.subID);
+		list_for_each_entry(wssid_e, &neighb->wssid, node) {
+			used += wlp_wss_wssid_e_print(buf + used,
+						      bufsize - used,
+						      wssid_e);
+		}
+		buf[used++] = '\n';
+		wlp_remove_neighbor_tmp_info(neighb);
+	}
+
+
+out:
+	mutex_unlock(&wlp->nbmutex);
+	return used;
+}
+
+
+/**
+ * Show properties of all WSS in neighborhood.
+ *
+ * Will trigger a complete discovery of WSS activated by this device and
+ * its neighbors.
+ */
+ssize_t wlp_neighborhood_show(struct wlp *wlp, char *buf)
+{
+	wlp_discover(wlp);
+	return wlp_wss_neighborhood_print_remove(wlp, buf, PAGE_SIZE);
+}
+EXPORT_SYMBOL_GPL(wlp_neighborhood_show);
+
+static
+ssize_t __wlp_wss_properties_show(struct wlp_wss *wss, char *buf,
+				  size_t bufsize)
+{
+	ssize_t result;
+
+	result = wlp_wss_uuid_print(buf, bufsize, &wss->wssid);
+	result += scnprintf(buf + result, bufsize - result, " ");
+	result += uwb_mac_addr_print(buf + result, bufsize - result,
+				     &wss->bcast);
+	result += scnprintf(buf + result, bufsize - result,
+			    " 0x%02x %u ", wss->hash, wss->secure_status);
+	result += wlp_wss_key_print(buf + result, bufsize - result,
+				    wss->master_key);
+	result += scnprintf(buf + result, bufsize - result, " 0x%02x ",
+			    wss->tag);
+	result += uwb_mac_addr_print(buf + result, bufsize - result,
+				     &wss->virtual_addr);
+	result += scnprintf(buf + result, bufsize - result, " %s", wss->name);
+	result += scnprintf(buf + result, bufsize - result,
+			    "\n\n#WSSID\n#WSS broadcast address\n"
+			    "#WSS hash\n#WSS secure status\n"
+			    "#WSS master key\n#WSS local tag\n"
+			    "#WSS local virtual EUI-48\n#WSS name\n");
+	return result;
+}
+
+/**
+ * Show which WSS is activated.
+ */
+ssize_t wlp_wss_activate_show(struct wlp_wss *wss, char *buf)
+{
+	int result = 0;
+
+	if (mutex_lock_interruptible(&wss->mutex))
+		goto out;
+	if (wss->state >= WLP_WSS_STATE_ACTIVE)
+		result = __wlp_wss_properties_show(wss, buf, PAGE_SIZE);
+	else
+		result = scnprintf(buf, PAGE_SIZE, "No local WSS active.\n");
+	result += scnprintf(buf + result, PAGE_SIZE - result,
+			"\n\n"
+			"# echo WSSID SECURE_STATUS ACCEPT_ENROLLMENT "
+			"NAME #create new WSS\n"
+			"# echo WSSID [DEV ADDR] #enroll in and activate "
+			"existing WSS, can request registrar\n"
+			"#\n"
+			"# WSSID is a 16 byte hex array. Eg. 12 A3 3B ... \n"
+			"# SECURE_STATUS 0 - unsecure, 1 - secure (default)\n"
+			"# ACCEPT_ENROLLMENT 0 - no, 1 - yes (default)\n"
+			"# NAME is the text string identifying the WSS\n"
+			"# DEV ADDR is the device address of neighbor "
+			"that should be registrar. Eg. 32:AB\n");
+
+	mutex_unlock(&wss->mutex);
+out:
+	return result;
+
+}
+EXPORT_SYMBOL_GPL(wlp_wss_activate_show);
+
+/**
+ * Create/activate a new WSS or enroll/activate in neighboring WSS
+ *
+ * The user can provide the WSSID of a WSS in which it wants to enroll.
+ * Only the WSSID is necessary if the WSS have been discovered before. If
+ * the WSS has not been discovered before, or the user wants to use a
+ * particular neighbor as its registrar, then the user can also provide a
+ * device address or the neighbor that will be used as registrar.
+ *
+ * A new WSS is created when the user provides a WSSID, secure status, and
+ * WSS name.
+ */
+ssize_t wlp_wss_activate_store(struct wlp_wss *wss,
+			       const char *buf, size_t size)
+{
+	ssize_t result = -EINVAL;
+	struct wlp_uuid wssid;
+	struct uwb_dev_addr dev;
+	struct uwb_dev_addr bcast = {.data = {0xff, 0xff} };
+	char name[65];
+	unsigned sec_status, accept;
+	memset(name, 0, sizeof(name));
+	result = sscanf(buf, "%02hhx %02hhx %02hhx %02hhx "
+			"%02hhx %02hhx %02hhx %02hhx "
+			"%02hhx %02hhx %02hhx %02hhx "
+			"%02hhx %02hhx %02hhx %02hhx "
+			"%02hhx:%02hhx",
+			&wssid.data[0] , &wssid.data[1],
+			&wssid.data[2] , &wssid.data[3],
+			&wssid.data[4] , &wssid.data[5],
+			&wssid.data[6] , &wssid.data[7],
+			&wssid.data[8] , &wssid.data[9],
+			&wssid.data[10], &wssid.data[11],
+			&wssid.data[12], &wssid.data[13],
+			&wssid.data[14], &wssid.data[15],
+			&dev.data[1], &dev.data[0]);
+	if (result == 16 || result == 17) {
+		result = sscanf(buf, "%02hhx %02hhx %02hhx %02hhx "
+				"%02hhx %02hhx %02hhx %02hhx "
+				"%02hhx %02hhx %02hhx %02hhx "
+				"%02hhx %02hhx %02hhx %02hhx "
+				"%u %u %64c",
+				&wssid.data[0] , &wssid.data[1],
+				&wssid.data[2] , &wssid.data[3],
+				&wssid.data[4] , &wssid.data[5],
+				&wssid.data[6] , &wssid.data[7],
+				&wssid.data[8] , &wssid.data[9],
+				&wssid.data[10], &wssid.data[11],
+				&wssid.data[12], &wssid.data[13],
+				&wssid.data[14], &wssid.data[15],
+				&sec_status, &accept, name);
+		if (result == 16)
+			result = wlp_wss_enroll_activate(wss, &wssid, &bcast);
+		else if (result == 19) {
+			sec_status = sec_status == 0 ? 0 : 1;
+			accept = accept == 0 ? 0 : 1;
+			/* We read name using %c, so the newline needs to be
+			 * removed */
+			if (strlen(name) != sizeof(name) - 1)
+				name[strlen(name) - 1] = '\0';
+			result = wlp_wss_create_activate(wss, &wssid, name,
+							 sec_status, accept);
+		} else
+			result = -EINVAL;
+	} else if (result == 18)
+		result = wlp_wss_enroll_activate(wss, &wssid, &dev);
+	else
+		result = -EINVAL;
+	return result < 0 ? result : size;
+}
+EXPORT_SYMBOL_GPL(wlp_wss_activate_store);
+
+/**
+ * Show the UUID of this host
+ */
+ssize_t wlp_uuid_show(struct wlp *wlp, char *buf)
+{
+	ssize_t result = 0;
+
+	mutex_lock(&wlp->mutex);
+	result = wlp_wss_uuid_print(buf, PAGE_SIZE, &wlp->uuid);
+	buf[result++] = '\n';
+	mutex_unlock(&wlp->mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_uuid_show);
+
+/**
+ * Store a new UUID for this host
+ *
+ * According to the spec this should be encoded as an octet string in the
+ * order the octets are shown in string representation in RFC 4122 (WLP
+ * 0.99 [Table 6])
+ *
+ * We do not check value provided by user.
+ */
+ssize_t wlp_uuid_store(struct wlp *wlp, const char *buf, size_t size)
+{
+	ssize_t result;
+	struct wlp_uuid uuid;
+
+	mutex_lock(&wlp->mutex);
+	result = sscanf(buf, "%02hhx %02hhx %02hhx %02hhx "
+			"%02hhx %02hhx %02hhx %02hhx "
+			"%02hhx %02hhx %02hhx %02hhx "
+			"%02hhx %02hhx %02hhx %02hhx ",
+			&uuid.data[0] , &uuid.data[1],
+			&uuid.data[2] , &uuid.data[3],
+			&uuid.data[4] , &uuid.data[5],
+			&uuid.data[6] , &uuid.data[7],
+			&uuid.data[8] , &uuid.data[9],
+			&uuid.data[10], &uuid.data[11],
+			&uuid.data[12], &uuid.data[13],
+			&uuid.data[14], &uuid.data[15]);
+	if (result != 16) {
+		result = -EINVAL;
+		goto error;
+	}
+	wlp->uuid = uuid;
+error:
+	mutex_unlock(&wlp->mutex);
+	return result < 0 ? result : size;
+}
+EXPORT_SYMBOL_GPL(wlp_uuid_store);
+
+/**
+ * Show contents of members of device information structure
+ */
+#define wlp_dev_info_show(type)						\
+ssize_t wlp_dev_##type##_show(struct wlp *wlp, char *buf)		\
+{									\
+	ssize_t result = 0;						\
+	mutex_lock(&wlp->mutex);					\
+	if (wlp->dev_info == NULL) {					\
+		result = __wlp_setup_device_info(wlp);			\
+		if (result < 0)						\
+			goto out;					\
+	}								\
+	result = scnprintf(buf, PAGE_SIZE, "%s\n", wlp->dev_info->type);\
+out:									\
+	mutex_unlock(&wlp->mutex);					\
+	return result;							\
+}									\
+EXPORT_SYMBOL_GPL(wlp_dev_##type##_show);
+
+wlp_dev_info_show(name)
+wlp_dev_info_show(model_name)
+wlp_dev_info_show(model_nr)
+wlp_dev_info_show(manufacturer)
+wlp_dev_info_show(serial)
+
+/**
+ * Store contents of members of device information structure
+ */
+#define wlp_dev_info_store(type, len)					\
+ssize_t wlp_dev_##type##_store(struct wlp *wlp, const char *buf, size_t size)\
+{									\
+	ssize_t result;							\
+	char format[10];						\
+	mutex_lock(&wlp->mutex);					\
+	if (wlp->dev_info == NULL) {					\
+		result = __wlp_alloc_device_info(wlp);			\
+		if (result < 0)						\
+			goto out;					\
+	}								\
+	memset(wlp->dev_info->type, 0, sizeof(wlp->dev_info->type));	\
+	sprintf(format, "%%%uc", len);					\
+	result = sscanf(buf, format, wlp->dev_info->type);		\
+out:									\
+	mutex_unlock(&wlp->mutex);					\
+	return result < 0 ? result : size;				\
+}									\
+EXPORT_SYMBOL_GPL(wlp_dev_##type##_store);
+
+wlp_dev_info_store(name, 32)
+wlp_dev_info_store(manufacturer, 64)
+wlp_dev_info_store(model_name, 32)
+wlp_dev_info_store(model_nr, 32)
+wlp_dev_info_store(serial, 32)
+
+static
+const char *__wlp_dev_category[] = {
+	[WLP_DEV_CAT_COMPUTER] = "Computer",
+	[WLP_DEV_CAT_INPUT] = "Input device",
+	[WLP_DEV_CAT_PRINT_SCAN_FAX_COPIER] = "Printer, scanner, FAX, or "
+					      "Copier",
+	[WLP_DEV_CAT_CAMERA] = "Camera",
+	[WLP_DEV_CAT_STORAGE] = "Storage Network",
+	[WLP_DEV_CAT_INFRASTRUCTURE] = "Infrastructure",
+	[WLP_DEV_CAT_DISPLAY] = "Display",
+	[WLP_DEV_CAT_MULTIM] = "Multimedia device",
+	[WLP_DEV_CAT_GAMING] = "Gaming device",
+	[WLP_DEV_CAT_TELEPHONE] = "Telephone",
+	[WLP_DEV_CAT_OTHER] = "Other",
+};
+
+static
+const char *wlp_dev_category_str(unsigned cat)
+{
+	if ((cat >= WLP_DEV_CAT_COMPUTER && cat <= WLP_DEV_CAT_TELEPHONE)
+	    || cat == WLP_DEV_CAT_OTHER)
+		return __wlp_dev_category[cat];
+	return "unknown category";
+}
+
+ssize_t wlp_dev_prim_category_show(struct wlp *wlp, char *buf)
+{
+	ssize_t result = 0;
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_setup_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = scnprintf(buf, PAGE_SIZE, "%s\n",
+		  wlp_dev_category_str(wlp->dev_info->prim_dev_type.category));
+out:
+	mutex_unlock(&wlp->mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_category_show);
+
+ssize_t wlp_dev_prim_category_store(struct wlp *wlp, const char *buf,
+				    size_t size)
+{
+	ssize_t result;
+	u16 cat;
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_alloc_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = sscanf(buf, "%hu", &cat);
+	if ((cat >= WLP_DEV_CAT_COMPUTER && cat <= WLP_DEV_CAT_TELEPHONE)
+	    || cat == WLP_DEV_CAT_OTHER)
+		wlp->dev_info->prim_dev_type.category = cat;
+	else
+		result = -EINVAL;
+out:
+	mutex_unlock(&wlp->mutex);
+	return result < 0 ? result : size;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_category_store);
+
+ssize_t wlp_dev_prim_OUI_show(struct wlp *wlp, char *buf)
+{
+	ssize_t result = 0;
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_setup_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = scnprintf(buf, PAGE_SIZE, "%02x:%02x:%02x\n",
+			   wlp->dev_info->prim_dev_type.OUI[0],
+			   wlp->dev_info->prim_dev_type.OUI[1],
+			   wlp->dev_info->prim_dev_type.OUI[2]);
+out:
+	mutex_unlock(&wlp->mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_OUI_show);
+
+ssize_t wlp_dev_prim_OUI_store(struct wlp *wlp, const char *buf, size_t size)
+{
+	ssize_t result;
+	u8 OUI[3];
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_alloc_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = sscanf(buf, "%hhx:%hhx:%hhx",
+			&OUI[0], &OUI[1], &OUI[2]);
+	if (result != 3) {
+		result = -EINVAL;
+		goto out;
+	} else
+		memcpy(wlp->dev_info->prim_dev_type.OUI, OUI, sizeof(OUI));
+out:
+	mutex_unlock(&wlp->mutex);
+	return result < 0 ? result : size;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_OUI_store);
+
+
+ssize_t wlp_dev_prim_OUI_sub_show(struct wlp *wlp, char *buf)
+{
+	ssize_t result = 0;
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_setup_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = scnprintf(buf, PAGE_SIZE, "%u\n",
+			   wlp->dev_info->prim_dev_type.OUIsubdiv);
+out:
+	mutex_unlock(&wlp->mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_OUI_sub_show);
+
+ssize_t wlp_dev_prim_OUI_sub_store(struct wlp *wlp, const char *buf,
+				   size_t size)
+{
+	ssize_t result;
+	unsigned sub;
+	u8 max_sub = ~0;
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_alloc_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = sscanf(buf, "%u", &sub);
+	if (sub <= max_sub)
+		wlp->dev_info->prim_dev_type.OUIsubdiv = sub;
+	else
+		result = -EINVAL;
+out:
+	mutex_unlock(&wlp->mutex);
+	return result < 0 ? result : size;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_OUI_sub_store);
+
+ssize_t wlp_dev_prim_subcat_show(struct wlp *wlp, char *buf)
+{
+	ssize_t result = 0;
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_setup_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = scnprintf(buf, PAGE_SIZE, "%u\n",
+			   wlp->dev_info->prim_dev_type.subID);
+out:
+	mutex_unlock(&wlp->mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_subcat_show);
+
+ssize_t wlp_dev_prim_subcat_store(struct wlp *wlp, const char *buf,
+				  size_t size)
+{
+	ssize_t result;
+	unsigned sub;
+	__le16 max_sub = ~0;
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info == NULL) {
+		result = __wlp_alloc_device_info(wlp);
+		if (result < 0)
+			goto out;
+	}
+	result = sscanf(buf, "%u", &sub);
+	if (sub <= max_sub)
+		wlp->dev_info->prim_dev_type.subID = sub;
+	else
+		result = -EINVAL;
+out:
+	mutex_unlock(&wlp->mutex);
+	return result < 0 ? result : size;
+}
+EXPORT_SYMBOL_GPL(wlp_dev_prim_subcat_store);
+
+/**
+ * Subsystem implementation for interaction with individual WSS via sysfs
+ *
+ * Followed instructions for subsystem in Documentation/filesystems/sysfs.txt
+ */
+
+#define kobj_to_wlp_wss(obj) container_of(obj, struct wlp_wss, kobj)
+#define attr_to_wlp_wss_attr(_attr) \
+	container_of(_attr, struct wlp_wss_attribute, attr)
+
+/**
+ * Sysfs subsystem: forward read calls
+ *
+ * Sysfs operation for forwarding read call to the show method of the
+ * attribute owner
+ */
+static
+ssize_t wlp_wss_attr_show(struct kobject *kobj, struct attribute *attr,
+			  char *buf)
+{
+	struct wlp_wss_attribute *wss_attr = attr_to_wlp_wss_attr(attr);
+	struct wlp_wss *wss = kobj_to_wlp_wss(kobj);
+	ssize_t ret = -EIO;
+
+	if (wss_attr->show)
+		ret = wss_attr->show(wss, buf);
+	return ret;
+}
+/**
+ * Sysfs subsystem: forward write calls
+ *
+ * Sysfs operation for forwarding write call to the store method of the
+ * attribute owner
+ */
+static
+ssize_t wlp_wss_attr_store(struct kobject *kobj, struct attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct wlp_wss_attribute *wss_attr = attr_to_wlp_wss_attr(attr);
+	struct wlp_wss *wss = kobj_to_wlp_wss(kobj);
+	ssize_t ret = -EIO;
+
+	if (wss_attr->store)
+		ret = wss_attr->store(wss, buf, count);
+	return ret;
+}
+
+static
+struct sysfs_ops wss_sysfs_ops = {
+	.show	= wlp_wss_attr_show,
+	.store	= wlp_wss_attr_store,
+};
+
+struct kobj_type wss_ktype = {
+	.release	= wlp_wss_release,
+	.sysfs_ops	= &wss_sysfs_ops,
+};
+
+
+/**
+ * Sysfs files for individual WSS
+ */
+
+/**
+ * Print static properties of this WSS
+ *
+ * The name of a WSS may not be null teminated. It's max size is 64 bytes
+ * so we copy it to a larger array just to make sure we print sane data.
+ */
+static ssize_t wlp_wss_properties_show(struct wlp_wss *wss, char *buf)
+{
+	int result = 0;
+
+	if (mutex_lock_interruptible(&wss->mutex))
+		goto out;
+	result = __wlp_wss_properties_show(wss, buf, PAGE_SIZE);
+	mutex_unlock(&wss->mutex);
+out:
+	return result;
+}
+WSS_ATTR(properties, S_IRUGO, wlp_wss_properties_show, NULL);
+
+/**
+ * Print all connected members of this WSS
+ * The EDA cache contains all members of WSS neighborhood.
+ */
+static ssize_t wlp_wss_members_show(struct wlp_wss *wss, char *buf)
+{
+	struct wlp *wlp = container_of(wss, struct wlp, wss);
+	return wlp_eda_show(wlp, buf);
+}
+WSS_ATTR(members, S_IRUGO, wlp_wss_members_show, NULL);
+
+static
+const char *__wlp_strstate[] = {
+	"none",
+	"partially enrolled",
+	"enrolled",
+	"active",
+	"connected",
+};
+
+static const char *wlp_wss_strstate(unsigned state)
+{
+	if (state >= ARRAY_SIZE(__wlp_strstate))
+		return "unknown state";
+	return __wlp_strstate[state];
+}
+
+/*
+ * Print current state of this WSS
+ */
+static ssize_t wlp_wss_state_show(struct wlp_wss *wss, char *buf)
+{
+	int result = 0;
+
+	if (mutex_lock_interruptible(&wss->mutex))
+		goto out;
+	result = scnprintf(buf, PAGE_SIZE, "%s\n",
+			   wlp_wss_strstate(wss->state));
+	mutex_unlock(&wss->mutex);
+out:
+	return result;
+}
+WSS_ATTR(state, S_IRUGO, wlp_wss_state_show, NULL);
+
+
+static
+struct attribute *wss_attrs[] = {
+	&wss_attr_properties.attr,
+	&wss_attr_members.attr,
+	&wss_attr_state.attr,
+	NULL,
+};
+
+struct attribute_group wss_attr_group = {
+	.name = NULL,	/* we want them in the same directory */
+	.attrs = wss_attrs,
+};

drivers/uwb/wlp/txrx.c

+/*
+ * WiMedia Logical Link Control Protocol (WLP)
+ * Message exchange infrastructure
+ *
+ * Copyright (C) 2007 Intel Corporation
+ * Reinette Chatre <reinette.chatre@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * FIXME: Docs
+ *
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/wlp.h>
+#define D_LOCAL 5
+#include <linux/uwb/debug.h>
+#include "wlp-internal.h"
+
+
+/**
+ * Direct incoming association msg to correct parsing routine
+ *
+ * We only expect D1, E1, C1, C3 messages as new. All other incoming
+ * association messages should form part of an established session that is
+ * handled elsewhere.
+ * The handling of these messages often require calling sleeping functions
+ * - this cannot be done in interrupt context. We use the kernel's
+ * workqueue to handle these messages.
+ */
+static
+void wlp_direct_assoc_frame(struct wlp *wlp, struct sk_buff *skb,
+			   struct uwb_dev_addr *src)
+{
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	struct wlp_frame_assoc *assoc = (void *) skb->data;
+	struct wlp_assoc_frame_ctx *frame_ctx;
+	d_fnstart(5, dev, "wlp %p, skb %p\n", wlp, skb);
+	frame_ctx = kmalloc(sizeof(*frame_ctx), GFP_ATOMIC);
+	if (frame_ctx == NULL) {
+		dev_err(dev, "WLP: Unable to allocate memory for association "
+			"frame handling.\n");
+		kfree_skb(skb);
+		goto out;
+	}
+	frame_ctx->wlp = wlp;
+	frame_ctx->skb = skb;
+	frame_ctx->src = *src;
+	switch (assoc->type) {
+	case WLP_ASSOC_D1:
+		d_printf(5, dev, "Received a D1 frame.\n");
+		INIT_WORK(&frame_ctx->ws, wlp_handle_d1_frame);
+		schedule_work(&frame_ctx->ws);
+		break;
+	case WLP_ASSOC_E1:
+		d_printf(5, dev, "Received a E1 frame. FIXME?\n");
+		kfree_skb(skb); /* Temporary until we handle it */
+		kfree(frame_ctx); /* Temporary until we handle it */
+		break;
+	case WLP_ASSOC_C1:
+		d_printf(5, dev, "Received a C1 frame.\n");
+		INIT_WORK(&frame_ctx->ws, wlp_handle_c1_frame);
+		schedule_work(&frame_ctx->ws);
+		break;
+	case WLP_ASSOC_C3:
+		d_printf(5, dev, "Received a C3 frame.\n");
+		INIT_WORK(&frame_ctx->ws, wlp_handle_c3_frame);
+		schedule_work(&frame_ctx->ws);
+		break;
+	default:
+		dev_err(dev, "Received unexpected association frame. "
+			"Type = %d \n", assoc->type);
+		kfree_skb(skb);
+		kfree(frame_ctx);
+		break;
+	}
+out:
+	d_fnend(5, dev, "wlp %p\n", wlp);
+}
+
+/**
+ * Process incoming association frame
+ *
+ * Although it could be possible to deal with some incoming association
+ * messages without creating a new session we are keeping things simple. We
+ * do not accept new association messages if there is a session in progress
+ * and the messages do not belong to that session.
+ *
+ * If an association message arrives that causes the creation of a session
+ * (WLP_ASSOC_E1) while we are in the process of creating a session then we
+ * rely on the neighbor mutex to protect the data. That is, the new session
+ * will not be started until the previous is completed.
+ */
+static
+void wlp_receive_assoc_frame(struct wlp *wlp, struct sk_buff *skb,
+			     struct uwb_dev_addr *src)
+{
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	struct wlp_frame_assoc *assoc = (void *) skb->data;
+	struct wlp_session *session = wlp->session;
+	u8 version;
+	d_fnstart(5, dev, "wlp %p, skb %p\n", wlp, skb);
+
+	if (wlp_get_version(wlp, &assoc->version, &version,
+			    sizeof(assoc->version)) < 0)
+		goto error;
+	if (version != WLP_VERSION) {
+		dev_err(dev, "Unsupported WLP version in association "
+			"message.\n");
+		goto error;
+	}
+	if (session != NULL) {
+		/* Function that created this session is still holding the
+		 * &wlp->mutex to protect this session. */
+		if (assoc->type == session->exp_message ||
+		    assoc->type == WLP_ASSOC_F0) {
+			if (!memcmp(&session->neighbor_addr, src,
+				   sizeof(*src))) {
+				session->data = skb;
+				(session->cb)(wlp);
+			} else {
+				dev_err(dev, "Received expected message from "
+					"unexpected source.  Expected message "
+					"%d or F0 from %02x:%02x, but received "
+					"it from %02x:%02x. Dropping.\n",
+					session->exp_message,
+					session->neighbor_addr.data[1],
+					session->neighbor_addr.data[0],
+					src->data[1], src->data[0]);
+				goto error;
+			}
+		} else {
+			dev_err(dev, "Association already in progress. "
+				"Dropping.\n");
+			goto error;
+		}
+	} else {
+		wlp_direct_assoc_frame(wlp, skb, src);
+	}
+	d_fnend(5, dev, "wlp %p\n", wlp);
+	return;
+error:
+	kfree_skb(skb);
+	d_fnend(5, dev, "wlp %p\n", wlp);
+}
+
+/**
+ * Verify incoming frame is from connected neighbor, prep to pass to WLP client
+ *
+ * Verification proceeds according to WLP 0.99 [7.3.1]. The source address
+ * is used to determine which neighbor is sending the frame and the WSS tag
+ * is used to know to which WSS the frame belongs (we only support one WSS
+ * so this test is straight forward).
+ * With the WSS found we need to ensure that we are connected before
+ * allowing the exchange of data frames.
+ */
+static
+int wlp_verify_prep_rx_frame(struct wlp *wlp, struct sk_buff *skb,
+			     struct uwb_dev_addr *src)
+{
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	int result = -EINVAL;
+	struct wlp_eda_node eda_entry;
+	struct wlp_frame_std_abbrv_hdr *hdr = (void *) skb->data;
+
+	d_fnstart(6, dev, "wlp %p, skb %p \n", wlp, skb);
+	/*verify*/
+	result = wlp_copy_eda_node(&wlp->eda, src, &eda_entry);
+	if (result < 0) {
+		if (printk_ratelimit())
+			dev_err(dev, "WLP: Incoming frame is from unknown "
+				"neighbor %02x:%02x.\n", src->data[1],
+				src->data[0]);
+		goto out;
+	}
+	if (hdr->tag != eda_entry.tag) {
+		if (printk_ratelimit())
+			dev_err(dev, "WLP: Tag of incoming frame from "
+				"%02x:%02x does not match expected tag. "
+				"Received 0x%02x, expected 0x%02x. \n",
+				src->data[1], src->data[0], hdr->tag,
+				eda_entry.tag);
+		result = -EINVAL;
+		goto out;
+	}
+	if (eda_entry.state != WLP_WSS_CONNECTED) {
+		if (printk_ratelimit())
+			dev_err(dev, "WLP: Incoming frame from "
+				"%02x:%02x does is not from connected WSS.\n",
+				src->data[1], src->data[0]);
+		result = -EINVAL;
+		goto out;
+	}
+	/*prep*/
+	skb_pull(skb, sizeof(*hdr));
+out:
+	d_fnend(6, dev, "wlp %p, skb %p, result = %d \n", wlp, skb, result);
+	return result;
+}
+
+/**
+ * Receive a WLP frame from device
+ *
+ * @returns: 1 if calling function should free the skb
+ *           0 if it successfully handled skb and freed it
+ *           0 if error occured, will free skb in this case
+ */
+int wlp_receive_frame(struct device *dev, struct wlp *wlp, struct sk_buff *skb,
+		      struct uwb_dev_addr *src)
+{
+	unsigned len = skb->len;
+	void *ptr = skb->data;
+	struct wlp_frame_hdr *hdr;
+	int result = 0;
+
+	d_fnstart(6, dev, "skb (%p), len (%u)\n", skb, len);
+	if (len < sizeof(*hdr)) {
+		dev_err(dev, "Not enough data to parse WLP header.\n");
+		result = -EINVAL;
+		goto out;
+	}
+	hdr = ptr;
+	d_dump(6, dev, hdr, sizeof(*hdr));
+	if (le16_to_cpu(hdr->mux_hdr) != WLP_PROTOCOL_ID) {
+		dev_err(dev, "Not a WLP frame type.\n");
+		result = -EINVAL;
+		goto out;
+	}
+	switch (hdr->type) {
+	case WLP_FRAME_STANDARD:
+		if (len < sizeof(struct wlp_frame_std_abbrv_hdr)) {
+			dev_err(dev, "Not enough data to parse Standard "
+				"WLP header.\n");
+			goto out;
+		}
+		result = wlp_verify_prep_rx_frame(wlp, skb, src);
+		if (result < 0) {
+			if (printk_ratelimit())
+				dev_err(dev, "WLP: Verification of frame "
+					"from neighbor %02x:%02x failed.\n",
+					src->data[1], src->data[0]);
+			goto out;
+		}
+		result = 1;
+		break;
+	case WLP_FRAME_ABBREVIATED:
+		dev_err(dev, "Abbreviated frame received. FIXME?\n");
+		kfree_skb(skb);
+		break;
+	case WLP_FRAME_CONTROL:
+		dev_err(dev, "Control frame received. FIXME?\n");
+		kfree_skb(skb);
+		break;
+	case WLP_FRAME_ASSOCIATION:
+		if (len < sizeof(struct wlp_frame_assoc)) {
+			dev_err(dev, "Not enough data to parse Association "
+				"WLP header.\n");
+			goto out;
+		}
+		d_printf(5, dev, "Association frame received.\n");
+		wlp_receive_assoc_frame(wlp, skb, src);
+		break;
+	default:
+		dev_err(dev, "Invalid frame received.\n");
+		result = -EINVAL;
+		break;
+	}
+out:
+	if (result < 0) {
+		kfree_skb(skb);
+		result = 0;
+	}
+	d_fnend(6, dev, "skb (%p)\n", skb);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_receive_frame);
+
+
+/**
+ * Verify frame from network stack, prepare for further transmission
+ *
+ * @skb:   the socket buffer that needs to be prepared for transmission (it
+ *         is in need of a WLP header). If this is a broadcast frame we take
+ *         over the entire transmission.
+ *         If it is a unicast the WSS connection should already be established
+ *         and transmission will be done by the calling function.
+ * @dst:   On return this will contain the device address to which the
+ *         frame is destined.
+ * @returns: 0 on success no tx : WLP header sucessfully applied to skb buffer,
+ *                                calling function can proceed with tx
+ *           1 on success with tx : WLP will take over transmission of this
+ *                                  frame
+ *           <0 on error
+ *
+ * The network stack (WLP client) is attempting to transmit a frame. We can
+ * only transmit data if a local WSS is at least active (connection will be
+ * done here if this is a broadcast frame and neighbor also has the WSS
+ * active).
+ *
+ * The frame can be either broadcast or unicast. Broadcast in a WSS is
+ * supported via multicast, but we don't support multicast yet (until
+ * devices start to support MAB IEs). If a broadcast frame needs to be
+ * transmitted it is treated as a unicast frame to each neighbor. In this
+ * case the WLP takes over transmission of the skb and returns 1
+ * to the caller to indicate so. Also, in this case, if a neighbor has the
+ * same WSS activated but is not connected then the WSS connection will be
+ * done at this time. The neighbor's virtual address will be learned at
+ * this time.
+ *
+ * The destination address in a unicast frame is the virtual address of the
+ * neighbor. This address only becomes known when a WSS connection is
+ * established. We thus rely on a broadcast frame to trigger the setup of
+ * WSS connections to all neighbors before we are able to send unicast
+ * frames to them. This seems reasonable as IP would usually use ARP first
+ * before any unicast frames are sent.
+ *
+ * If we are already connected to the neighbor (neighbor's virtual address
+ * is known) we just prepare the WLP header and the caller will continue to
+ * send the frame.
+ *
+ * A failure in this function usually indicates something that cannot be
+ * fixed automatically. So, if this function fails (@return < 0) the calling
+ * function should not retry to send the frame as it will very likely keep
+ * failing.
+ *
+ */
+int wlp_prepare_tx_frame(struct device *dev, struct wlp *wlp,
+			 struct sk_buff *skb, struct uwb_dev_addr *dst)
+{
+	int result = -EINVAL;
+	struct ethhdr *eth_hdr = (void *) skb->data;
+
+	d_fnstart(6, dev, "wlp (%p), skb (%p) \n", wlp, skb);
+	if (is_broadcast_ether_addr(eth_hdr->h_dest)) {
+		d_printf(6, dev, "WLP: handling broadcast frame. \n");
+		result = wlp_eda_for_each(&wlp->eda, wlp_wss_send_copy, skb);
+		if (result < 0) {
+			if (printk_ratelimit())
+				dev_err(dev, "Unable to handle broadcast "
+					"frame from WLP client.\n");
+			goto out;
+		}
+		dev_kfree_skb_irq(skb);
+		result = 1;
+		/* Frame will be transmitted by WLP. */
+	} else {
+		d_printf(6, dev, "WLP: handling unicast frame. \n");
+		result = wlp_eda_for_virtual(&wlp->eda, eth_hdr->h_dest, dst,
+					     wlp_wss_prep_hdr, skb);
+		if (unlikely(result < 0)) {
+			if (printk_ratelimit())
+				dev_err(dev, "Unable to prepare "
+					"skb for transmission. \n");
+			goto out;
+		}
+	}
+out:
+	d_fnend(6, dev, "wlp (%p), skb (%p). result = %d \n", wlp, skb, result);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_prepare_tx_frame);

drivers/uwb/wlp/wlp-internal.h

+/*
+ * WiMedia Logical Link Control Protocol (WLP)
+ * Internal API
+ *
+ * Copyright (C) 2007 Intel Corporation
+ * Reinette Chatre <reinette.chatre@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ */
+
+#ifndef __WLP_INTERNAL_H__
+#define __WLP_INTERNAL_H__
+
+/**
+ * State of WSS connection
+ *
+ * A device needs to connect to a neighbor in an activated WSS before data
+ * can be transmitted. The spec also distinguishes between a new connection
+ * attempt and a connection attempt after previous connection attempts. The
+ * state WLP_WSS_CONNECT_FAILED is used for this scenario. See WLP 0.99
+ * [7.2.6]
+ */
+enum wlp_wss_connect {
+	WLP_WSS_UNCONNECTED = 0,
+	WLP_WSS_CONNECTED,
+	WLP_WSS_CONNECT_FAILED,
+};
+
+extern struct kobj_type wss_ktype;
+extern struct attribute_group wss_attr_group;
+
+extern int uwb_rc_ie_add(struct uwb_rc *, const struct uwb_ie_hdr *, size_t);
+extern int uwb_rc_ie_rm(struct uwb_rc *, enum uwb_ie);
+
+
+/* This should be changed to a dynamic array where entries are sorted
+ * by eth_addr and search is done in a binary form
+ *
+ * Although thinking twice about it: this technologie's maximum reach
+ * is 10 meters...unless you want to pack too much stuff in around
+ * your radio controller/WLP device, the list will probably not be
+ * too big.
+ *
+ * In any case, there is probably some data structure in the kernel
+ * than we could reused for that already.
+ *
+ * The below structure is really just good while we support one WSS per
+ * host.
+ */
+struct wlp_eda_node {
+	struct list_head list_node;
+	unsigned char eth_addr[ETH_ALEN];
+	struct uwb_dev_addr dev_addr;
+	struct wlp_wss *wss;
+	unsigned char virt_addr[ETH_ALEN];
+	u8 tag;
+	enum wlp_wss_connect state;
+};
+
+typedef int (*wlp_eda_for_each_f)(struct wlp *, struct wlp_eda_node *, void *);
+
+extern void wlp_eda_init(struct wlp_eda *);
+extern void wlp_eda_release(struct wlp_eda *);
+extern int wlp_eda_create_node(struct wlp_eda *,
+			       const unsigned char eth_addr[ETH_ALEN],
+			       const struct uwb_dev_addr *);
+extern void wlp_eda_rm_node(struct wlp_eda *, const struct uwb_dev_addr *);
+extern int wlp_eda_update_node(struct wlp_eda *,
+			       const struct uwb_dev_addr *,
+			       struct wlp_wss *,
+			       const unsigned char virt_addr[ETH_ALEN],
+			       const u8, const enum wlp_wss_connect);
+extern int wlp_eda_update_node_state(struct wlp_eda *,
+				     const struct uwb_dev_addr *,
+				     const enum wlp_wss_connect);
+
+extern int wlp_copy_eda_node(struct wlp_eda *, struct uwb_dev_addr *,
+			     struct wlp_eda_node *);
+extern int wlp_eda_for_each(struct wlp_eda *, wlp_eda_for_each_f , void *);
+extern int wlp_eda_for_virtual(struct wlp_eda *,
+			       const unsigned char eth_addr[ETH_ALEN],
+			       struct uwb_dev_addr *,
+			       wlp_eda_for_each_f , void *);
+
+
+extern void wlp_remove_neighbor_tmp_info(struct wlp_neighbor_e *);
+
+extern size_t wlp_wss_key_print(char *, size_t, u8 *);
+
+/* Function called when no more references to WSS exists */
+extern void wlp_wss_release(struct kobject *);
+
+extern void wlp_wss_reset(struct wlp_wss *);
+extern int wlp_wss_create_activate(struct wlp_wss *, struct wlp_uuid *,
+				   char *, unsigned, unsigned);
+extern int wlp_wss_enroll_activate(struct wlp_wss *, struct wlp_uuid *,
+				   struct uwb_dev_addr *);
+extern ssize_t wlp_discover(struct wlp *);
+
+extern int wlp_enroll_neighbor(struct wlp *, struct wlp_neighbor_e *,
+			       struct wlp_wss *, struct wlp_uuid *);
+extern int wlp_wss_is_active(struct wlp *, struct wlp_wss *,
+			     struct uwb_dev_addr *);
+
+struct wlp_assoc_conn_ctx {
+	struct work_struct ws;
+	struct wlp *wlp;
+	struct sk_buff *skb;
+	struct wlp_eda_node eda_entry;
+};
+
+
+extern int wlp_wss_connect_prep(struct wlp *, struct wlp_eda_node *, void *);
+extern int wlp_wss_send_copy(struct wlp *, struct wlp_eda_node *, void *);
+
+
+/* Message handling */
+struct wlp_assoc_frame_ctx {
+	struct work_struct ws;
+	struct wlp *wlp;
+	struct sk_buff *skb;
+	struct uwb_dev_addr src;
+};
+
+extern int wlp_wss_prep_hdr(struct wlp *, struct wlp_eda_node *, void *);
+extern void wlp_handle_d1_frame(struct work_struct *);
+extern int wlp_parse_d2_frame_to_cache(struct wlp *, struct sk_buff *,
+				       struct wlp_neighbor_e *);
+extern int wlp_parse_d2_frame_to_enroll(struct wlp_wss *, struct sk_buff *,
+					struct wlp_neighbor_e *,
+					struct wlp_uuid *);
+extern void wlp_handle_c1_frame(struct work_struct *);
+extern void wlp_handle_c3_frame(struct work_struct *);
+extern int wlp_parse_c3c4_frame(struct wlp *, struct sk_buff *,
+				struct wlp_uuid *, u8 *,
+				struct uwb_mac_addr *);
+extern int wlp_parse_f0(struct wlp *, struct sk_buff *);
+extern int wlp_send_assoc_frame(struct wlp *, struct wlp_wss *,
+				struct uwb_dev_addr *, enum wlp_assoc_type);
+extern ssize_t wlp_get_version(struct wlp *, struct wlp_attr_version *,
+			       u8 *, ssize_t);
+extern ssize_t wlp_get_wssid(struct wlp *, struct wlp_attr_wssid *,
+			     struct wlp_uuid *, ssize_t);
+extern int __wlp_alloc_device_info(struct wlp *);
+extern int __wlp_setup_device_info(struct wlp *);
+
+extern struct wlp_wss_attribute wss_attribute_properties;
+extern struct wlp_wss_attribute wss_attribute_members;
+extern struct wlp_wss_attribute wss_attribute_state;
+
+static inline
+size_t wlp_wss_uuid_print(char *buf, size_t bufsize, struct wlp_uuid *uuid)
+{
+	size_t result;
+
+	result = scnprintf(buf, bufsize,
+			  "%02x:%02x:%02x:%02x:%02x:%02x:"
+			  "%02x:%02x:%02x:%02x:%02x:%02x:"
+			  "%02x:%02x:%02x:%02x",
+			  uuid->data[0], uuid->data[1],
+			  uuid->data[2], uuid->data[3],
+			  uuid->data[4], uuid->data[5],
+			  uuid->data[6], uuid->data[7],
+			  uuid->data[8], uuid->data[9],
+			  uuid->data[10], uuid->data[11],
+			  uuid->data[12], uuid->data[13],
+			  uuid->data[14], uuid->data[15]);
+	return result;
+}
+
+/**
+ * FIXME: How should a nonce be displayed?
+ */
+static inline
+size_t wlp_wss_nonce_print(char *buf, size_t bufsize, struct wlp_nonce *nonce)
+{
+	size_t result;
+
+	result = scnprintf(buf, bufsize,
+			  "%02x %02x %02x %02x %02x %02x "
+			  "%02x %02x %02x %02x %02x %02x "
+			  "%02x %02x %02x %02x",
+			  nonce->data[0], nonce->data[1],
+			  nonce->data[2], nonce->data[3],
+			  nonce->data[4], nonce->data[5],
+			  nonce->data[6], nonce->data[7],
+			  nonce->data[8], nonce->data[9],
+			  nonce->data[10], nonce->data[11],
+			  nonce->data[12], nonce->data[13],
+			  nonce->data[14], nonce->data[15]);
+	return result;
+}
+
+
+static inline
+void wlp_session_cb(struct wlp *wlp)
+{
+	struct completion *completion = wlp->session->cb_priv;
+	complete(completion);
+}
+
+static inline
+int wlp_uuid_is_set(struct wlp_uuid *uuid)
+{
+	struct wlp_uuid zero_uuid = { .data = { 0x00, 0x00, 0x00, 0x00,
+						0x00, 0x00, 0x00, 0x00,
+						0x00, 0x00, 0x00, 0x00,
+						0x00, 0x00, 0x00, 0x00} };
+
+	if (!memcmp(uuid, &zero_uuid, sizeof(*uuid)))
+		return 0;
+	return 1;
+}
+
+#endif /* __WLP_INTERNAL_H__ */

drivers/uwb/wlp/wlp-lc.c

+/*
+ * WiMedia Logical Link Control Protocol (WLP)
+ *
+ * Copyright (C) 2005-2006 Intel Corporation
+ * Reinette Chatre <reinette.chatre@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * FIXME: docs
+ */
+
+#include <linux/wlp.h>
+#define D_LOCAL 6
+#include <linux/uwb/debug.h>
+#include "wlp-internal.h"
+
+
+static
+void wlp_neighbor_init(struct wlp_neighbor_e *neighbor)
+{
+	INIT_LIST_HEAD(&neighbor->wssid);
+}
+
+/**
+ * Create area for device information storage
+ *
+ * wlp->mutex must be held
+ */
+int __wlp_alloc_device_info(struct wlp *wlp)
+{
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	BUG_ON(wlp->dev_info != NULL);
+	wlp->dev_info = kzalloc(sizeof(struct wlp_device_info), GFP_KERNEL);
+	if (wlp->dev_info == NULL) {
+		dev_err(dev, "WLP: Unable to allocate memory for "
+			"device information.\n");
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+
+/**
+ * Fill in device information using function provided by driver
+ *
+ * wlp->mutex must be held
+ */
+static
+void __wlp_fill_device_info(struct wlp *wlp)
+{
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+
+	BUG_ON(wlp->fill_device_info == NULL);
+	d_printf(6, dev, "Retrieving device information "
+			 "from device driver.\n");
+	wlp->fill_device_info(wlp, wlp->dev_info);
+}
+
+/**
+ * Setup device information
+ *
+ * Allocate area for device information and populate it.
+ *
+ * wlp->mutex must be held
+ */
+int __wlp_setup_device_info(struct wlp *wlp)
+{
+	int result;
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+
+	result = __wlp_alloc_device_info(wlp);
+	if (result < 0) {
+		dev_err(dev, "WLP: Unable to allocate area for "
+			"device information.\n");
+		return result;
+	}
+	__wlp_fill_device_info(wlp);
+	return 0;
+}
+
+/**
+ * Remove information about neighbor stored temporarily
+ *
+ * Information learned during discovey should only be stored when the
+ * device enrolls in the neighbor's WSS. We do need to store this
+ * information temporarily in order to present it to the user.
+ *
+ * We are only interested in keeping neighbor WSS information if that
+ * neighbor is accepting enrollment.
+ *
+ * should be called with wlp->nbmutex held
+ */
+void wlp_remove_neighbor_tmp_info(struct wlp_neighbor_e *neighbor)
+{
+	struct wlp_wssid_e *wssid_e, *next;
+	u8 keep;
+	if (!list_empty(&neighbor->wssid)) {
+		list_for_each_entry_safe(wssid_e, next, &neighbor->wssid,
+					 node) {
+			if (wssid_e->info != NULL) {
+				keep = wssid_e->info->accept_enroll;
+				kfree(wssid_e->info);
+				wssid_e->info = NULL;
+				if (!keep) {
+					list_del(&wssid_e->node);
+					kfree(wssid_e);
+				}
+			}
+		}
+	}
+	if (neighbor->info != NULL) {
+		kfree(neighbor->info);
+		neighbor->info = NULL;
+	}
+}
+
+/**
+ * Populate WLP neighborhood cache with neighbor information
+ *
+ * A new neighbor is found. If it is discoverable then we add it to the
+ * neighborhood cache.
+ *
+ */
+static
+int wlp_add_neighbor(struct wlp *wlp, struct uwb_dev *dev)
+{
+	int result = 0;
+	int discoverable;
+	struct wlp_neighbor_e *neighbor;
+
+	d_fnstart(6, &dev->dev, "uwb %p \n", dev);
+	d_printf(6, &dev->dev, "Found neighbor device %02x:%02x \n",
+		 dev->dev_addr.data[1], dev->dev_addr.data[0]);
+	/**
+	 * FIXME:
+	 * Use contents of WLP IE found in beacon cache to determine if
+	 * neighbor is discoverable.
+	 * The device does not support WLP IE yet so this still needs to be
+	 * done. Until then we assume all devices are discoverable.
+	 */
+	discoverable = 1; /* will be changed when FIXME disappears */
+	if (discoverable) {
+		/* Add neighbor to cache for discovery */
+		neighbor = kzalloc(sizeof(*neighbor), GFP_KERNEL);
+		if (neighbor == NULL) {
+			dev_err(&dev->dev, "Unable to create memory for "
+				"new neighbor. \n");
+			result = -ENOMEM;
+			goto error_no_mem;
+		}
+		wlp_neighbor_init(neighbor);
+		uwb_dev_get(dev);
+		neighbor->uwb_dev = dev;
+		list_add(&neighbor->node, &wlp->neighbors);
+	}
+error_no_mem:
+	d_fnend(6, &dev->dev, "uwb %p, result = %d \n", dev, result);
+	return result;
+}
+
+/**
+ * Remove one neighbor from cache
+ */
+static
+void __wlp_neighbor_release(struct wlp_neighbor_e *neighbor)
+{
+	struct wlp_wssid_e *wssid_e, *next_wssid_e;
+
+	list_for_each_entry_safe(wssid_e, next_wssid_e,
+				 &neighbor->wssid, node) {
+		list_del(&wssid_e->node);
+		kfree(wssid_e);
+	}
+	uwb_dev_put(neighbor->uwb_dev);
+	list_del(&neighbor->node);
+	kfree(neighbor);
+}
+
+/**
+ * Clear entire neighborhood cache.
+ */
+static
+void __wlp_neighbors_release(struct wlp *wlp)
+{
+	struct wlp_neighbor_e *neighbor, *next;
+	if (list_empty(&wlp->neighbors))
+		return;
+	list_for_each_entry_safe(neighbor, next, &wlp->neighbors, node) {
+		__wlp_neighbor_release(neighbor);
+	}
+}
+
+static
+void wlp_neighbors_release(struct wlp *wlp)
+{
+	mutex_lock(&wlp->nbmutex);
+	__wlp_neighbors_release(wlp);
+	mutex_unlock(&wlp->nbmutex);
+}
+
+
+
+/**
+ * Send D1 message to neighbor, receive D2 message
+ *
+ * @neighbor: neighbor to which D1 message will be sent
+ * @wss:      if not NULL, it is an enrollment request for this WSS
+ * @wssid:    if wss not NULL, this is the wssid of the WSS in which we
+ *            want to enroll
+ *
+ * A D1/D2 exchange is done for one of two reasons: discovery or
+ * enrollment. If done for discovery the D1 message is sent to the neighbor
+ * and the contents of the D2 response is stored in a temporary cache.
+ * If done for enrollment the @wss and @wssid are provided also. In this
+ * case the D1 message is sent to the neighbor, the D2 response is parsed
+ * for enrollment of the WSS with wssid.
+ *
+ * &wss->mutex is held
+ */
+static
+int wlp_d1d2_exchange(struct wlp *wlp, struct wlp_neighbor_e *neighbor,
+		      struct wlp_wss *wss, struct wlp_uuid *wssid)
+{
+	int result;
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	DECLARE_COMPLETION_ONSTACK(completion);
+	struct wlp_session session;
+	struct sk_buff  *skb;
+	struct wlp_frame_assoc *resp;
+	struct uwb_dev_addr *dev_addr = &neighbor->uwb_dev->dev_addr;
+
+	mutex_lock(&wlp->mutex);
+	if (!wlp_uuid_is_set(&wlp->uuid)) {
+		dev_err(dev, "WLP: UUID is not set. Set via sysfs to "
+			"proceed.\n");
+		result = -ENXIO;
+		goto out;
+	}
+	/* Send D1 association frame */
+	result = wlp_send_assoc_frame(wlp, wss, dev_addr, WLP_ASSOC_D1);
+	if (result < 0) {
+		dev_err(dev, "Unable to send D1 frame to neighbor "
+			"%02x:%02x (%d)\n", dev_addr->data[1],
+			dev_addr->data[0], result);
+		d_printf(6, dev, "Add placeholders into buffer next to "
+			 "neighbor information we have (dev address).\n");
+		goto out;
+	}
+	/* Create session, wait for response */
+	session.exp_message = WLP_ASSOC_D2;
+	session.cb = wlp_session_cb;
+	session.cb_priv = &completion;
+	session.neighbor_addr = *dev_addr;
+	BUG_ON(wlp->session != NULL);
+	wlp->session = &session;
+	/* Wait for D2/F0 frame */
+	result = wait_for_completion_interruptible_timeout(&completion,
+						   WLP_PER_MSG_TIMEOUT * HZ);
+	if (result == 0) {
+		result = -ETIMEDOUT;
+		dev_err(dev, "Timeout while sending D1 to neighbor "
+			     "%02x:%02x.\n", dev_addr->data[1],
+			     dev_addr->data[0]);
+		goto error_session;
+	}
+	if (result < 0) {
+		dev_err(dev, "Unable to discover/enroll neighbor %02x:%02x.\n",
+			dev_addr->data[1], dev_addr->data[0]);
+		goto error_session;
+	}
+	/* Parse message in session->data: it will be either D2 or F0 */
+	skb = session.data;
+	resp = (void *) skb->data;
+	d_printf(6, dev, "Received response to D1 frame. \n");
+	d_dump(6, dev, skb->data, skb->len > 72 ? 72 : skb->len);
+
+	if (resp->type == WLP_ASSOC_F0) {
+		result = wlp_parse_f0(wlp, skb);
+		if (result < 0)
+			dev_err(dev, "WLP: Unable to parse F0 from neighbor "
+				"%02x:%02x.\n", dev_addr->data[1],
+				dev_addr->data[0]);
+		result = -EINVAL;
+		goto error_resp_parse;
+	}
+	if (wss == NULL) {
+		/* Discovery */
+		result = wlp_parse_d2_frame_to_cache(wlp, skb, neighbor);
+		if (result < 0) {
+			dev_err(dev, "WLP: Unable to parse D2 message from "
+				"neighbor %02x:%02x for discovery.\n",
+				dev_addr->data[1], dev_addr->data[0]);
+			goto error_resp_parse;
+		}
+	} else {
+		/* Enrollment */
+		result = wlp_parse_d2_frame_to_enroll(wss, skb, neighbor,
+						      wssid);
+		if (result < 0) {
+			dev_err(dev, "WLP: Unable to parse D2 message from "
+				"neighbor %02x:%02x for enrollment.\n",
+				dev_addr->data[1], dev_addr->data[0]);
+			goto error_resp_parse;
+		}
+	}
+error_resp_parse:
+	kfree_skb(skb);
+error_session:
+	wlp->session = NULL;
+out:
+	mutex_unlock(&wlp->mutex);
+	return result;
+}
+
+/**
+ * Enroll into WSS of provided WSSID by using neighbor as registrar
+ *
+ * &wss->mutex is held
+ */
+int wlp_enroll_neighbor(struct wlp *wlp, struct wlp_neighbor_e *neighbor,
+			struct wlp_wss *wss, struct wlp_uuid *wssid)
+{
+	int result = 0;
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	char buf[WLP_WSS_UUID_STRSIZE];
+	struct uwb_dev_addr *dev_addr = &neighbor->uwb_dev->dev_addr;
+	wlp_wss_uuid_print(buf, sizeof(buf), wssid);
+	d_fnstart(6, dev, "wlp %p, neighbor %p, wss %p, wssid %p (%s)\n",
+		  wlp, neighbor, wss, wssid, buf);
+	d_printf(6, dev, "Complete me.\n");
+	result =  wlp_d1d2_exchange(wlp, neighbor, wss, wssid);
+	if (result < 0) {
+		dev_err(dev, "WLP: D1/D2 message exchange for enrollment "
+			"failed. result = %d \n", result);
+		goto out;
+	}
+	if (wss->state != WLP_WSS_STATE_PART_ENROLLED) {
+		dev_err(dev, "WLP: Unable to enroll into WSS %s using "
+			"neighbor %02x:%02x. \n", buf,
+			dev_addr->data[1], dev_addr->data[0]);
+		result = -EINVAL;
+		goto out;
+	}
+	if (wss->secure_status == WLP_WSS_SECURE) {
+		dev_err(dev, "FIXME: need to complete secure enrollment.\n");
+		result = -EINVAL;
+		goto error;
+	} else {
+		wss->state = WLP_WSS_STATE_ENROLLED;
+		d_printf(2, dev, "WLP: Success Enrollment into unsecure WSS "
+			 "%s using neighbor %02x:%02x. \n", buf,
+			 dev_addr->data[1], dev_addr->data[0]);
+	}
+
+	d_fnend(6, dev, "wlp %p, neighbor %p, wss %p, wssid %p (%s)\n",
+		  wlp, neighbor, wss, wssid, buf);
+out:
+	return result;
+error:
+	wlp_wss_reset(wss);
+	return result;
+}
+
+/**
+ * Discover WSS information of neighbor's active WSS
+ */
+static
+int wlp_discover_neighbor(struct wlp *wlp,
+			  struct wlp_neighbor_e *neighbor)
+{
+	return wlp_d1d2_exchange(wlp, neighbor, NULL, NULL);
+}
+
+
+/**
+ * Each neighbor in the neighborhood cache is discoverable. Discover it.
+ *
+ * Discovery is done through sending of D1 association frame and parsing
+ * the D2 association frame response. Only wssid from D2 will be included
+ * in neighbor cache, rest is just displayed to user and forgotten.
+ *
+ * The discovery is not done in parallel. This is simple and enables us to
+ * maintain only one association context.
+ *
+ * The discovery of one neighbor does not affect the other, but if the
+ * discovery of a neighbor fails it is removed from the neighborhood cache.
+ */
+static
+int wlp_discover_all_neighbors(struct wlp *wlp)
+{
+	int result = 0;
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	struct wlp_neighbor_e *neighbor, *next;
+
+	list_for_each_entry_safe(neighbor, next, &wlp->neighbors, node) {
+		result = wlp_discover_neighbor(wlp, neighbor);
+		if (result < 0) {
+			dev_err(dev, "WLP: Unable to discover neighbor "
+				"%02x:%02x, removing from neighborhood. \n",
+				neighbor->uwb_dev->dev_addr.data[1],
+				neighbor->uwb_dev->dev_addr.data[0]);
+			__wlp_neighbor_release(neighbor);
+		}
+	}
+	return result;
+}
+
+static int wlp_add_neighbor_helper(struct device *dev, void *priv)
+{
+	struct wlp *wlp = priv;
+	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
+
+	return wlp_add_neighbor(wlp, uwb_dev);
+}
+
+/**
+ * Discover WLP neighborhood
+ *
+ * Will send D1 association frame to all devices in beacon group that have
+ * discoverable bit set in WLP IE. D2 frames will be received, information
+ * displayed to user in @buf. Partial information (from D2 association
+ * frame) will be cached to assist with future association
+ * requests.
+ *
+ * The discovery of the WLP neighborhood is triggered by the user. This
+ * should occur infrequently and we thus free current cache and re-allocate
+ * memory if needed.
+ *
+ * If one neighbor fails during initial discovery (determining if it is a
+ * neighbor or not), we fail all - note that interaction with neighbor has
+ * not occured at this point so if a failure occurs we know something went wrong
+ * locally. We thus undo everything.
+ */
+ssize_t wlp_discover(struct wlp *wlp)
+{
+	int result = 0;
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+
+	d_fnstart(6, dev, "wlp %p \n", wlp);
+	mutex_lock(&wlp->nbmutex);
+	/* Clear current neighborhood cache. */
+	__wlp_neighbors_release(wlp);
+	/* Determine which devices in neighborhood. Repopulate cache. */
+	result = uwb_dev_for_each(wlp->rc, wlp_add_neighbor_helper, wlp);
+	if (result < 0) {
+		/* May have partial neighbor information, release all. */
+		__wlp_neighbors_release(wlp);
+		goto error_dev_for_each;
+	}
+	/* Discover the properties of devices in neighborhood. */
+	result = wlp_discover_all_neighbors(wlp);
+	/* In case of failure we still print our partial results. */
+	if (result < 0) {
+		dev_err(dev, "Unable to fully discover neighborhood. \n");
+		result = 0;
+	}
+error_dev_for_each:
+	mutex_unlock(&wlp->nbmutex);
+	d_fnend(6, dev, "wlp %p \n", wlp);
+	return result;
+}
+
+/**
+ * Handle events from UWB stack
+ *
+ * We handle events conservatively. If a neighbor goes off the air we
+ * remove it from the neighborhood. If an association process is in
+ * progress this function will block waiting for the nbmutex to become
+ * free. The association process will thus be allowed to complete before it
+ * is removed.
+ */
+static
+void wlp_uwb_notifs_cb(void *_wlp, struct uwb_dev *uwb_dev,
+		       enum uwb_notifs event)
+{
+	struct wlp *wlp = _wlp;
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	struct wlp_neighbor_e *neighbor, *next;
+	int result;
+	switch (event) {
+	case UWB_NOTIF_ONAIR:
+		d_printf(6, dev, "UWB device %02x:%02x is onair\n",
+				uwb_dev->dev_addr.data[1],
+				uwb_dev->dev_addr.data[0]);
+		result = wlp_eda_create_node(&wlp->eda,
+					     uwb_dev->mac_addr.data,
+					     &uwb_dev->dev_addr);
+		if (result < 0)
+			dev_err(dev, "WLP: Unable to add new neighbor "
+				"%02x:%02x to EDA cache.\n",
+				uwb_dev->dev_addr.data[1],
+				uwb_dev->dev_addr.data[0]);
+		break;
+	case UWB_NOTIF_OFFAIR:
+		d_printf(6, dev, "UWB device %02x:%02x is offair\n",
+				uwb_dev->dev_addr.data[1],
+				uwb_dev->dev_addr.data[0]);
+		wlp_eda_rm_node(&wlp->eda, &uwb_dev->dev_addr);
+		mutex_lock(&wlp->nbmutex);
+		list_for_each_entry_safe(neighbor, next, &wlp->neighbors,
+					 node) {
+			if (neighbor->uwb_dev == uwb_dev) {
+				d_printf(6, dev, "Removing device from "
+					 "neighborhood.\n");
+				__wlp_neighbor_release(neighbor);
+			}
+		}
+		mutex_unlock(&wlp->nbmutex);
+		break;
+	default:
+		dev_err(dev, "don't know how to handle event %d from uwb\n",
+				event);
+	}
+}
+
+int wlp_setup(struct wlp *wlp, struct uwb_rc *rc)
+{
+	struct device *dev = &rc->uwb_dev.dev;
+	int result;
+
+	d_fnstart(6, dev, "wlp %p\n", wlp);
+	BUG_ON(wlp->fill_device_info == NULL);
+	BUG_ON(wlp->xmit_frame == NULL);
+	BUG_ON(wlp->stop_queue == NULL);
+	BUG_ON(wlp->start_queue == NULL);
+	wlp->rc = rc;
+	wlp_eda_init(&wlp->eda);/* Set up address cache */
+	wlp->uwb_notifs_handler.cb = wlp_uwb_notifs_cb;
+	wlp->uwb_notifs_handler.data = wlp;
+	uwb_notifs_register(rc, &wlp->uwb_notifs_handler);
+
+	uwb_pal_init(&wlp->pal);
+	result = uwb_pal_register(rc, &wlp->pal);
+	if (result < 0)
+		uwb_notifs_deregister(wlp->rc, &wlp->uwb_notifs_handler);
+
+	d_fnend(6, dev, "wlp %p, result = %d\n", wlp, result);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wlp_setup);
+
+void wlp_remove(struct wlp *wlp)
+{
+	struct device *dev = &wlp->rc->uwb_dev.dev;
+	d_fnstart(6, dev, "wlp %p\n", wlp);
+	wlp_neighbors_release(wlp);
+	uwb_pal_unregister(wlp->rc, &wlp->pal);
+	uwb_notifs_deregister(wlp->rc, &wlp->uwb_notifs_handler);
+	wlp_eda_release(&wlp->eda);
+	mutex_lock(&wlp->mutex);
+	if (wlp->dev_info != NULL)
+		kfree(wlp->dev_info);
+	mutex_unlock(&wlp->mutex);
+	wlp->rc = NULL;
+	/* We have to use NULL here because this function can be called
+	 * when the device disappeared. */
+	d_fnend(6, NULL, "wlp %p\n", wlp);
+}
+EXPORT_SYMBOL_GPL(wlp_remove);
+
+/**
+ * wlp_reset_all - reset the WLP hardware
+ * @wlp: the WLP device to reset.
+ *
+ * This schedules a full hardware reset of the WLP device.  The radio
+ * controller and any other PALs will also be reset.
+ */
+void wlp_reset_all(struct wlp *wlp)
+{
+	uwb_rc_reset_all(wlp->rc);
+}
+EXPORT_SYMBOL_GPL(wlp_reset_all);