drivers/uwb/lc-dev.c - kernel/msm-4.9 - Gitiles

 /*
  * Ultra Wide Band
  * Life cycle of devices
  *
  * 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.
  *
  *
  * FIXME: docs
  */
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/device.h>
 #include <linux/export.h>
 #include <linux/err.h>
 #include <linux/kdev_t.h>
 #include <linux/random.h>
 #include <linux/stat.h>
 #include "uwb-internal.h"

 /* We initialize addresses to 0xff (invalid, as it is bcast) */
 static inline void uwb_dev_addr_init(struct uwb_dev_addr *addr)
 {
 	memset(&addr->data, 0xff, sizeof(addr->data));
 }

 static inline void uwb_mac_addr_init(struct uwb_mac_addr *addr)
 {
 	memset(&addr->data, 0xff, sizeof(addr->data));
 }

 /* @returns !0 if a device @addr is a broadcast address */
 static inline int uwb_dev_addr_bcast(const struct uwb_dev_addr *addr)
 {
 	static const struct uwb_dev_addr bcast = { .data = { 0xff, 0xff } };
 	return !uwb_dev_addr_cmp(addr, &bcast);
 }

 /*
  * Add callback @new to be called when an event occurs in @rc.
  */
 int uwb_notifs_register(struct uwb_rc *rc, struct uwb_notifs_handler *new)
 {
 	if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
 		return -ERESTARTSYS;
 	list_add(&new->list_node, &rc->notifs_chain.list);
 	mutex_unlock(&rc->notifs_chain.mutex);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(uwb_notifs_register);

 /*
  * Remove event handler (callback)
  */
 int uwb_notifs_deregister(struct uwb_rc *rc, struct uwb_notifs_handler *entry)
 {
 	if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
 		return -ERESTARTSYS;
 	list_del(&entry->list_node);
 	mutex_unlock(&rc->notifs_chain.mutex);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(uwb_notifs_deregister);

 /*
  * Notify all event handlers of a given event on @rc
  *
  * We are called with a valid reference to the device, or NULL if the
  * event is not for a particular event (e.g., a BG join event).
  */
 void uwb_notify(struct uwb_rc *rc, struct uwb_dev *uwb_dev, enum uwb_notifs event)
 {
 	struct uwb_notifs_handler *handler;
 	if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
 		return;
 	if (!list_empty(&rc->notifs_chain.list)) {
 		list_for_each_entry(handler, &rc->notifs_chain.list, list_node) {
 			handler->cb(handler->data, uwb_dev, event);
 		}
 	}
 	mutex_unlock(&rc->notifs_chain.mutex);
 }

 /*
  * Release the backing device of a uwb_dev that has been dynamically allocated.
  */
 static void uwb_dev_sys_release(struct device *dev)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);

 	uwb_bce_put(uwb_dev->bce);
 	memset(uwb_dev, 0x69, sizeof(*uwb_dev));
 	kfree(uwb_dev);
 }

 /*
  * Initialize a UWB device instance
  *
  * Alloc, zero and call this function.
  */
 void uwb_dev_init(struct uwb_dev *uwb_dev)
 {
 	mutex_init(&uwb_dev->mutex);
 	device_initialize(&uwb_dev->dev);
 	uwb_dev->dev.release = uwb_dev_sys_release;
 	uwb_dev_addr_init(&uwb_dev->dev_addr);
 	uwb_mac_addr_init(&uwb_dev->mac_addr);
 	bitmap_fill(uwb_dev->streams, UWB_NUM_GLOBAL_STREAMS);
 }

 static ssize_t uwb_dev_EUI_48_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	char addr[UWB_ADDR_STRSIZE];

 	uwb_mac_addr_print(addr, sizeof(addr), &uwb_dev->mac_addr);
 	return sprintf(buf, "%s\n", addr);
 }
 static DEVICE_ATTR(EUI_48, S_IRUGO, uwb_dev_EUI_48_show, NULL);

 static ssize_t uwb_dev_DevAddr_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	char addr[UWB_ADDR_STRSIZE];

 	uwb_dev_addr_print(addr, sizeof(addr), &uwb_dev->dev_addr);
 	return sprintf(buf, "%s\n", addr);
 }
 static DEVICE_ATTR(DevAddr, S_IRUGO, uwb_dev_DevAddr_show, NULL);

 /*
  * Show the BPST of this device.
  *
  * Calculated from the receive time of the device's beacon and it's
  * slot number.
  */
 static ssize_t uwb_dev_BPST_show(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	struct uwb_beca_e *bce;
 	struct uwb_beacon_frame *bf;
 	u16 bpst;

 	bce = uwb_dev->bce;
 	mutex_lock(&bce->mutex);
 	bf = (struct uwb_beacon_frame *)bce->be->BeaconInfo;
 	bpst = bce->be->wBPSTOffset
 		- (u16)(bf->Beacon_Slot_Number * UWB_BEACON_SLOT_LENGTH_US);
 	mutex_unlock(&bce->mutex);

 	return sprintf(buf, "%d\n", bpst);
 }
 static DEVICE_ATTR(BPST, S_IRUGO, uwb_dev_BPST_show, NULL);

 /*
  * Show the IEs a device is beaconing
  *
  * We need to access the beacon cache, so we just lock it really
  * quick, print the IEs and unlock.
  *
  * We have a reference on the cache entry, so that should be
  * quite safe.
  */
 static ssize_t uwb_dev_IEs_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);

 	return uwb_bce_print_IEs(uwb_dev, uwb_dev->bce, buf, PAGE_SIZE);
 }
 static DEVICE_ATTR(IEs, S_IRUGO | S_IWUSR, uwb_dev_IEs_show, NULL);

 static ssize_t uwb_dev_LQE_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	struct uwb_beca_e *bce = uwb_dev->bce;
 	size_t result;

 	mutex_lock(&bce->mutex);
 	result = stats_show(&uwb_dev->bce->lqe_stats, buf);
 	mutex_unlock(&bce->mutex);
 	return result;
 }

 static ssize_t uwb_dev_LQE_store(struct device *dev,
 				 struct device_attribute *attr,
 				 const char *buf, size_t size)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	struct uwb_beca_e *bce = uwb_dev->bce;
 	ssize_t result;

 	mutex_lock(&bce->mutex);
 	result = stats_store(&uwb_dev->bce->lqe_stats, buf, size);
 	mutex_unlock(&bce->mutex);
 	return result;
 }
 static DEVICE_ATTR(LQE, S_IRUGO | S_IWUSR, uwb_dev_LQE_show, uwb_dev_LQE_store);

 static ssize_t uwb_dev_RSSI_show(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	struct uwb_beca_e *bce = uwb_dev->bce;
 	size_t result;

 	mutex_lock(&bce->mutex);
 	result = stats_show(&uwb_dev->bce->rssi_stats, buf);
 	mutex_unlock(&bce->mutex);
 	return result;
 }

 static ssize_t uwb_dev_RSSI_store(struct device *dev,
 				  struct device_attribute *attr,
 				  const char *buf, size_t size)
 {
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	struct uwb_beca_e *bce = uwb_dev->bce;
 	ssize_t result;

 	mutex_lock(&bce->mutex);
 	result = stats_store(&uwb_dev->bce->rssi_stats, buf, size);
 	mutex_unlock(&bce->mutex);
 	return result;
 }
 static DEVICE_ATTR(RSSI, S_IRUGO | S_IWUSR, uwb_dev_RSSI_show, uwb_dev_RSSI_store);


 static struct attribute *dev_attrs[] = {
 	&dev_attr_EUI_48.attr,
 	&dev_attr_DevAddr.attr,
 	&dev_attr_BPST.attr,
 	&dev_attr_IEs.attr,
 	&dev_attr_LQE.attr,
 	&dev_attr_RSSI.attr,
 	NULL,
 };

 static struct attribute_group dev_attr_group = {
 	.attrs = dev_attrs,
 };

 static const struct attribute_group *groups[] = {
 	&dev_attr_group,
 	NULL,
 };

 /**
  * Device SYSFS registration
  *
  *
  */
 static int __uwb_dev_sys_add(struct uwb_dev *uwb_dev, struct device *parent_dev)
 {
 	struct device *dev;

 	dev = &uwb_dev->dev;
 	/* Device sysfs files are only useful for neighbor devices not
 	   local radio controllers. */
 	if (&uwb_dev->rc->uwb_dev != uwb_dev)
 		dev->groups = groups;
 	dev->parent = parent_dev;
 	dev_set_drvdata(dev, uwb_dev);

 	return device_add(dev);
 }


 static void __uwb_dev_sys_rm(struct uwb_dev *uwb_dev)
 {
 	dev_set_drvdata(&uwb_dev->dev, NULL);
 	device_del(&uwb_dev->dev);
 }


 /**
  * Register and initialize a new UWB device
  *
  * Did you call uwb_dev_init() on it?
  *
  * @parent_rc: is the parent radio controller who has the link to the
  *             device. When registering the UWB device that is a UWB
  *             Radio Controller, we point back to it.
  *
  * If registering the device that is part of a radio, caller has set
  * rc->uwb_dev->dev. Otherwise it is to be left NULL--a new one will
  * be allocated.
  */
 int uwb_dev_add(struct uwb_dev *uwb_dev, struct device *parent_dev,
 		struct uwb_rc *parent_rc)
 {
 	int result;
 	struct device *dev;

 	BUG_ON(uwb_dev == NULL);
 	BUG_ON(parent_dev == NULL);
 	BUG_ON(parent_rc == NULL);

 	mutex_lock(&uwb_dev->mutex);
 	dev = &uwb_dev->dev;
 	uwb_dev->rc = parent_rc;
 	result = __uwb_dev_sys_add(uwb_dev, parent_dev);
 	if (result < 0)
 		printk(KERN_ERR "UWB: unable to register dev %s with sysfs: %d\n",
 		       dev_name(dev), result);
 	mutex_unlock(&uwb_dev->mutex);
 	return result;
 }


 void uwb_dev_rm(struct uwb_dev *uwb_dev)
 {
 	mutex_lock(&uwb_dev->mutex);
 	__uwb_dev_sys_rm(uwb_dev);
 	mutex_unlock(&uwb_dev->mutex);
 }


 static
 int __uwb_dev_try_get(struct device *dev, void *__target_uwb_dev)
 {
 	struct uwb_dev *target_uwb_dev = __target_uwb_dev;
 	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
 	if (uwb_dev == target_uwb_dev) {
 		uwb_dev_get(uwb_dev);
 		return 1;
 	} else
 		return 0;
 }


 /**
  * Given a UWB device descriptor, validate and refcount it
  *
  * @returns NULL if the device does not exist or is quiescing; the ptr to
  *               it otherwise.
  */
 struct uwb_dev *uwb_dev_try_get(struct uwb_rc *rc, struct uwb_dev *uwb_dev)
 {
 	if (uwb_dev_for_each(rc, __uwb_dev_try_get, uwb_dev))
 		return uwb_dev;
 	else
 		return NULL;
 }
 EXPORT_SYMBOL_GPL(uwb_dev_try_get);


 /**
  * Remove a device from the system [grunt for other functions]
  */
 int __uwb_dev_offair(struct uwb_dev *uwb_dev, struct uwb_rc *rc)
 {
 	struct device *dev = &uwb_dev->dev;
 	char macbuf[UWB_ADDR_STRSIZE], devbuf[UWB_ADDR_STRSIZE];

 	uwb_mac_addr_print(macbuf, sizeof(macbuf), &uwb_dev->mac_addr);
 	uwb_dev_addr_print(devbuf, sizeof(devbuf), &uwb_dev->dev_addr);
 	dev_info(dev, "uwb device (mac %s dev %s) disconnected from %s %s\n",
 		 macbuf, devbuf,
 		 rc ? rc->uwb_dev.dev.parent->bus->name : "n/a",
 		 rc ? dev_name(rc->uwb_dev.dev.parent) : "");
 	uwb_dev_rm(uwb_dev);
 	list_del(&uwb_dev->bce->node);
 	uwb_bce_put(uwb_dev->bce);
 	uwb_dev_put(uwb_dev);	/* for the creation in _onair() */

 	return 0;
 }


 /**
  * A device went off the air, clean up after it!
  *
  * This is called by the UWB Daemon (through the beacon purge function
  * uwb_bcn_cache_purge) when it is detected that a device has been in
  * radio silence for a while.
  *
  * If this device is actually a local radio controller we don't need
  * to go through the offair process, as it is not registered as that.
  *
  * NOTE: uwb_bcn_cache.mutex is held!
  */
 void uwbd_dev_offair(struct uwb_beca_e *bce)
 {
 	struct uwb_dev *uwb_dev;

 	uwb_dev = bce->uwb_dev;
 	if (uwb_dev) {
 		uwb_notify(uwb_dev->rc, uwb_dev, UWB_NOTIF_OFFAIR);
 		__uwb_dev_offair(uwb_dev, uwb_dev->rc);
 	}
 }


 /**
  * A device went on the air, start it up!
  *
  * This is called by the UWB Daemon when it is detected that a device
  * has popped up in the radio range of the radio controller.
  *
  * It will just create the freaking device, register the beacon and
  * stuff and yatla, done.
  *
  *
  * NOTE: uwb_beca.mutex is held, bce->mutex is held
  */
 void uwbd_dev_onair(struct uwb_rc *rc, struct uwb_beca_e *bce)
 {
 	int result;
 	struct device *dev = &rc->uwb_dev.dev;
 	struct uwb_dev *uwb_dev;
 	char macbuf[UWB_ADDR_STRSIZE], devbuf[UWB_ADDR_STRSIZE];

 	uwb_mac_addr_print(macbuf, sizeof(macbuf), bce->mac_addr);
 	uwb_dev_addr_print(devbuf, sizeof(devbuf), &bce->dev_addr);
 	uwb_dev = kzalloc(sizeof(struct uwb_dev), GFP_KERNEL);
 	if (uwb_dev == NULL) {
 		dev_err(dev, "new device %s: Cannot allocate memory\n",
 			macbuf);
 		return;
 	}
 	uwb_dev_init(uwb_dev);		/* This sets refcnt to one, we own it */
 	uwb_dev->mac_addr = *bce->mac_addr;
 	uwb_dev->dev_addr = bce->dev_addr;
 	dev_set_name(&uwb_dev->dev, macbuf);
 	result = uwb_dev_add(uwb_dev, &rc->uwb_dev.dev, rc);
 	if (result < 0) {
 		dev_err(dev, "new device %s: cannot instantiate device\n",
 			macbuf);
 		goto error_dev_add;
 	}
 	/* plug the beacon cache */
 	bce->uwb_dev = uwb_dev;
 	uwb_dev->bce = bce;
 	uwb_bce_get(bce);		/* released in uwb_dev_sys_release() */
 	dev_info(dev, "uwb device (mac %s dev %s) connected to %s %s\n",
 		 macbuf, devbuf, rc->uwb_dev.dev.parent->bus->name,
 		 dev_name(rc->uwb_dev.dev.parent));
 	uwb_notify(rc, uwb_dev, UWB_NOTIF_ONAIR);
 	return;

 error_dev_add:
 	kfree(uwb_dev);
 	return;
 }

 /**
  * Iterate over the list of UWB devices, calling a @function on each
  *
  * See docs for bus_for_each()....
  *
  * @rc:       radio controller for the devices.
  * @function: function to call.
  * @priv:     data to pass to @function.
  * @returns:  0 if no invocation of function() returned a value
  *            different to zero. That value otherwise.
  */
 int uwb_dev_for_each(struct uwb_rc *rc, uwb_dev_for_each_f function, void *priv)
 {
 	return device_for_each_child(&rc->uwb_dev.dev, priv, function);
 }
 EXPORT_SYMBOL_GPL(uwb_dev_for_each);
	/*
	* Ultra Wide Band
	* Life cycle of devices
	*
	* 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.
	*
	*
	* FIXME: docs
	*/
	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/device.h>
	#include <linux/export.h>
	#include <linux/err.h>
	#include <linux/kdev_t.h>
	#include <linux/random.h>
	#include <linux/stat.h>
	#include "uwb-internal.h"

	/* We initialize addresses to 0xff (invalid, as it is bcast) */
	static inline void uwb_dev_addr_init(struct uwb_dev_addr *addr)
	{
	memset(&addr->data, 0xff, sizeof(addr->data));
	}

	static inline void uwb_mac_addr_init(struct uwb_mac_addr *addr)
	{
	memset(&addr->data, 0xff, sizeof(addr->data));
	}

	/* @returns !0 if a device @addr is a broadcast address */
	static inline int uwb_dev_addr_bcast(const struct uwb_dev_addr *addr)
	{
	static const struct uwb_dev_addr bcast = { .data = { 0xff, 0xff } };
	return !uwb_dev_addr_cmp(addr, &bcast);
	}

	/*
	* Add callback @new to be called when an event occurs in @rc.
	*/
	int uwb_notifs_register(struct uwb_rc rc, struct uwb_notifs_handler new)
	{
	if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
	return -ERESTARTSYS;
	list_add(&new->list_node, &rc->notifs_chain.list);
	mutex_unlock(&rc->notifs_chain.mutex);
	return 0;
	}
	EXPORT_SYMBOL_GPL(uwb_notifs_register);

	/*
	* Remove event handler (callback)
	*/
	int uwb_notifs_deregister(struct uwb_rc rc, struct uwb_notifs_handler entry)
	{
	if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
	return -ERESTARTSYS;
	list_del(&entry->list_node);
	mutex_unlock(&rc->notifs_chain.mutex);
	return 0;
	}
	EXPORT_SYMBOL_GPL(uwb_notifs_deregister);

	/*
	* Notify all event handlers of a given event on @rc
	*
	* We are called with a valid reference to the device, or NULL if the
	* event is not for a particular event (e.g., a BG join event).
	*/
	void uwb_notify(struct uwb_rc rc, struct uwb_dev uwb_dev, enum uwb_notifs event)
	{
	struct uwb_notifs_handler *handler;
	if (mutex_lock_interruptible(&rc->notifs_chain.mutex))
	return;
	if (!list_empty(&rc->notifs_chain.list)) {
	list_for_each_entry(handler, &rc->notifs_chain.list, list_node) {
	handler->cb(handler->data, uwb_dev, event);
	}
	}
	mutex_unlock(&rc->notifs_chain.mutex);
	}

	/*
	* Release the backing device of a uwb_dev that has been dynamically allocated.
	*/
	static void uwb_dev_sys_release(struct device *dev)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);

	uwb_bce_put(uwb_dev->bce);
	memset(uwb_dev, 0x69, sizeof(*uwb_dev));
	kfree(uwb_dev);
	}

	/*
	* Initialize a UWB device instance
	*
	* Alloc, zero and call this function.
	*/
	void uwb_dev_init(struct uwb_dev *uwb_dev)
	{
	mutex_init(&uwb_dev->mutex);
	device_initialize(&uwb_dev->dev);
	uwb_dev->dev.release = uwb_dev_sys_release;
	uwb_dev_addr_init(&uwb_dev->dev_addr);
	uwb_mac_addr_init(&uwb_dev->mac_addr);
	bitmap_fill(uwb_dev->streams, UWB_NUM_GLOBAL_STREAMS);
	}

	static ssize_t uwb_dev_EUI_48_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	char addr[UWB_ADDR_STRSIZE];

	uwb_mac_addr_print(addr, sizeof(addr), &uwb_dev->mac_addr);
	return sprintf(buf, "%s\n", addr);
	}
	static DEVICE_ATTR(EUI_48, S_IRUGO, uwb_dev_EUI_48_show, NULL);

	static ssize_t uwb_dev_DevAddr_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	char addr[UWB_ADDR_STRSIZE];

	uwb_dev_addr_print(addr, sizeof(addr), &uwb_dev->dev_addr);
	return sprintf(buf, "%s\n", addr);
	}
	static DEVICE_ATTR(DevAddr, S_IRUGO, uwb_dev_DevAddr_show, NULL);

	/*
	* Show the BPST of this device.
	*
	* Calculated from the receive time of the device's beacon and it's
	* slot number.
	*/
	static ssize_t uwb_dev_BPST_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	struct uwb_beca_e *bce;
	struct uwb_beacon_frame *bf;
	u16 bpst;

	bce = uwb_dev->bce;
	mutex_lock(&bce->mutex);
	bf = (struct uwb_beacon_frame *)bce->be->BeaconInfo;
	bpst = bce->be->wBPSTOffset
	- (u16)(bf->Beacon_Slot_Number * UWB_BEACON_SLOT_LENGTH_US);
	mutex_unlock(&bce->mutex);

	return sprintf(buf, "%d\n", bpst);
	}
	static DEVICE_ATTR(BPST, S_IRUGO, uwb_dev_BPST_show, NULL);

	/*
	* Show the IEs a device is beaconing
	*
	* We need to access the beacon cache, so we just lock it really
	* quick, print the IEs and unlock.
	*
	* We have a reference on the cache entry, so that should be
	* quite safe.
	*/
	static ssize_t uwb_dev_IEs_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);

	return uwb_bce_print_IEs(uwb_dev, uwb_dev->bce, buf, PAGE_SIZE);
	}
	static DEVICE_ATTR(IEs, S_IRUGO \| S_IWUSR, uwb_dev_IEs_show, NULL);

	static ssize_t uwb_dev_LQE_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	struct uwb_beca_e *bce = uwb_dev->bce;
	size_t result;

	mutex_lock(&bce->mutex);
	result = stats_show(&uwb_dev->bce->lqe_stats, buf);
	mutex_unlock(&bce->mutex);
	return result;
	}

	static ssize_t uwb_dev_LQE_store(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t size)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	struct uwb_beca_e *bce = uwb_dev->bce;
	ssize_t result;

	mutex_lock(&bce->mutex);
	result = stats_store(&uwb_dev->bce->lqe_stats, buf, size);
	mutex_unlock(&bce->mutex);
	return result;
	}
	static DEVICE_ATTR(LQE, S_IRUGO \| S_IWUSR, uwb_dev_LQE_show, uwb_dev_LQE_store);

	static ssize_t uwb_dev_RSSI_show(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	struct uwb_beca_e *bce = uwb_dev->bce;
	size_t result;

	mutex_lock(&bce->mutex);
	result = stats_show(&uwb_dev->bce->rssi_stats, buf);
	mutex_unlock(&bce->mutex);
	return result;
	}

	static ssize_t uwb_dev_RSSI_store(struct device *dev,
	struct device_attribute *attr,
	const char *buf, size_t size)
	{
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	struct uwb_beca_e *bce = uwb_dev->bce;
	ssize_t result;

	mutex_lock(&bce->mutex);
	result = stats_store(&uwb_dev->bce->rssi_stats, buf, size);
	mutex_unlock(&bce->mutex);
	return result;
	}
	static DEVICE_ATTR(RSSI, S_IRUGO \| S_IWUSR, uwb_dev_RSSI_show, uwb_dev_RSSI_store);


	static struct attribute *dev_attrs[] = {
	&dev_attr_EUI_48.attr,
	&dev_attr_DevAddr.attr,
	&dev_attr_BPST.attr,
	&dev_attr_IEs.attr,
	&dev_attr_LQE.attr,
	&dev_attr_RSSI.attr,
	NULL,
	};

	static struct attribute_group dev_attr_group = {
	.attrs = dev_attrs,
	};

	static const struct attribute_group *groups[] = {
	&dev_attr_group,
	NULL,
	};

	/**
	* Device SYSFS registration
	*
	*
	*/
	static int __uwb_dev_sys_add(struct uwb_dev uwb_dev, struct device parent_dev)
	{
	struct device *dev;

	dev = &uwb_dev->dev;
	/* Device sysfs files are only useful for neighbor devices not
	local radio controllers. */
	if (&uwb_dev->rc->uwb_dev != uwb_dev)
	dev->groups = groups;
	dev->parent = parent_dev;
	dev_set_drvdata(dev, uwb_dev);

	return device_add(dev);
	}


	static void __uwb_dev_sys_rm(struct uwb_dev *uwb_dev)
	{
	dev_set_drvdata(&uwb_dev->dev, NULL);
	device_del(&uwb_dev->dev);
	}


	/**
	* Register and initialize a new UWB device
	*
	* Did you call uwb_dev_init() on it?
	*
	* @parent_rc: is the parent radio controller who has the link to the
	* device. When registering the UWB device that is a UWB
	* Radio Controller, we point back to it.
	*
	* If registering the device that is part of a radio, caller has set
	* rc->uwb_dev->dev. Otherwise it is to be left NULL--a new one will
	* be allocated.
	*/
	int uwb_dev_add(struct uwb_dev uwb_dev, struct device parent_dev,
	struct uwb_rc *parent_rc)
	{
	int result;
	struct device *dev;

	BUG_ON(uwb_dev == NULL);
	BUG_ON(parent_dev == NULL);
	BUG_ON(parent_rc == NULL);

	mutex_lock(&uwb_dev->mutex);
	dev = &uwb_dev->dev;
	uwb_dev->rc = parent_rc;
	result = __uwb_dev_sys_add(uwb_dev, parent_dev);
	if (result < 0)
	printk(KERN_ERR "UWB: unable to register dev %s with sysfs: %d\n",
	dev_name(dev), result);
	mutex_unlock(&uwb_dev->mutex);
	return result;
	}


	void uwb_dev_rm(struct uwb_dev *uwb_dev)
	{
	mutex_lock(&uwb_dev->mutex);
	__uwb_dev_sys_rm(uwb_dev);
	mutex_unlock(&uwb_dev->mutex);
	}


	static
	int __uwb_dev_try_get(struct device dev, void __target_uwb_dev)
	{
	struct uwb_dev *target_uwb_dev = __target_uwb_dev;
	struct uwb_dev *uwb_dev = to_uwb_dev(dev);
	if (uwb_dev == target_uwb_dev) {
	uwb_dev_get(uwb_dev);
	return 1;
	} else
	return 0;
	}


	/**
	* Given a UWB device descriptor, validate and refcount it
	*
	* @returns NULL if the device does not exist or is quiescing; the ptr to
	* it otherwise.
	*/
	struct uwb_dev uwb_dev_try_get(struct uwb_rc rc, struct uwb_dev *uwb_dev)
	{
	if (uwb_dev_for_each(rc, __uwb_dev_try_get, uwb_dev))
	return uwb_dev;
	else
	return NULL;
	}
	EXPORT_SYMBOL_GPL(uwb_dev_try_get);


	/**
	* Remove a device from the system [grunt for other functions]
	*/
	int __uwb_dev_offair(struct uwb_dev uwb_dev, struct uwb_rc rc)
	{
	struct device *dev = &uwb_dev->dev;
	char macbuf[UWB_ADDR_STRSIZE], devbuf[UWB_ADDR_STRSIZE];

	uwb_mac_addr_print(macbuf, sizeof(macbuf), &uwb_dev->mac_addr);
	uwb_dev_addr_print(devbuf, sizeof(devbuf), &uwb_dev->dev_addr);
	dev_info(dev, "uwb device (mac %s dev %s) disconnected from %s %s\n",
	macbuf, devbuf,
	rc ? rc->uwb_dev.dev.parent->bus->name : "n/a",
	rc ? dev_name(rc->uwb_dev.dev.parent) : "");
	uwb_dev_rm(uwb_dev);
	list_del(&uwb_dev->bce->node);
	uwb_bce_put(uwb_dev->bce);
	uwb_dev_put(uwb_dev); /* for the creation in _onair() */

	return 0;
	}


	/**
	* A device went off the air, clean up after it!
	*
	* This is called by the UWB Daemon (through the beacon purge function
	* uwb_bcn_cache_purge) when it is detected that a device has been in
	* radio silence for a while.
	*
	* If this device is actually a local radio controller we don't need
	* to go through the offair process, as it is not registered as that.
	*
	* NOTE: uwb_bcn_cache.mutex is held!
	*/
	void uwbd_dev_offair(struct uwb_beca_e *bce)
	{
	struct uwb_dev *uwb_dev;

	uwb_dev = bce->uwb_dev;
	if (uwb_dev) {
	uwb_notify(uwb_dev->rc, uwb_dev, UWB_NOTIF_OFFAIR);
	__uwb_dev_offair(uwb_dev, uwb_dev->rc);
	}
	}


	/**
	* A device went on the air, start it up!
	*
	* This is called by the UWB Daemon when it is detected that a device
	* has popped up in the radio range of the radio controller.
	*
	* It will just create the freaking device, register the beacon and
	* stuff and yatla, done.
	*
	*
	* NOTE: uwb_beca.mutex is held, bce->mutex is held
	*/
	void uwbd_dev_onair(struct uwb_rc rc, struct uwb_beca_e bce)
	{
	int result;
	struct device *dev = &rc->uwb_dev.dev;
	struct uwb_dev *uwb_dev;
	char macbuf[UWB_ADDR_STRSIZE], devbuf[UWB_ADDR_STRSIZE];

	uwb_mac_addr_print(macbuf, sizeof(macbuf), bce->mac_addr);
	uwb_dev_addr_print(devbuf, sizeof(devbuf), &bce->dev_addr);
	uwb_dev = kzalloc(sizeof(struct uwb_dev), GFP_KERNEL);
	if (uwb_dev == NULL) {
	dev_err(dev, "new device %s: Cannot allocate memory\n",
	macbuf);
	return;
	}
	uwb_dev_init(uwb_dev); /* This sets refcnt to one, we own it */
	uwb_dev->mac_addr = *bce->mac_addr;
	uwb_dev->dev_addr = bce->dev_addr;
	dev_set_name(&uwb_dev->dev, macbuf);
	result = uwb_dev_add(uwb_dev, &rc->uwb_dev.dev, rc);
	if (result < 0) {
	dev_err(dev, "new device %s: cannot instantiate device\n",
	macbuf);
	goto error_dev_add;
	}
	/* plug the beacon cache */
	bce->uwb_dev = uwb_dev;
	uwb_dev->bce = bce;
	uwb_bce_get(bce); /* released in uwb_dev_sys_release() */
	dev_info(dev, "uwb device (mac %s dev %s) connected to %s %s\n",
	macbuf, devbuf, rc->uwb_dev.dev.parent->bus->name,
	dev_name(rc->uwb_dev.dev.parent));
	uwb_notify(rc, uwb_dev, UWB_NOTIF_ONAIR);
	return;

	error_dev_add:
	kfree(uwb_dev);
	return;
	}

	/**
	* Iterate over the list of UWB devices, calling a @function on each
	*
	* See docs for bus_for_each()....
	*
	* @rc: radio controller for the devices.
	* @function: function to call.
	* @priv: data to pass to @function.
	* @returns: 0 if no invocation of function() returned a value
	* different to zero. That value otherwise.
	*/
	int uwb_dev_for_each(struct uwb_rc rc, uwb_dev_for_each_f function, void priv)
	{
	return device_for_each_child(&rc->uwb_dev.dev, priv, function);
	}
	EXPORT_SYMBOL_GPL(uwb_dev_for_each);