[net-next-2.6.git] / drivers / uwb / uwbd.c

/*
 * Ultra Wide Band
 * Neighborhood Management Daemon
 *
 * 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.
 *
 *
 * This daemon takes care of maintaing information that describes the
 * UWB neighborhood that the radios in this machine can see. It also
 * keeps a tab of which devices are visible, makes sure each HC sits
 * on a different channel to avoid interfering, etc.
 *
 * Different drivers (radio controller, device, any API in general)
 * communicate with this daemon through an event queue. Daemon wakes
 * up, takes a list of events and handles them one by one; handling
 * function is extracted from a table based on the event's type and
 * subtype. Events are freed only if the handling function says so.
 *
 *   . Lock protecting the event list has to be an spinlock and locked
 *     with IRQSAVE because it might be called from an interrupt
 *     context (ie: when events arrive and the notification drops
 *     down from the ISR).
 *
 *   . UWB radio controller drivers queue events to the daemon using
 *     uwbd_event_queue(). They just get the event, chew it to make it
 *     look like UWBD likes it and pass it in a buffer allocated with
 *     uwb_event_alloc().
 *
 * EVENTS
 *
 * Events have a type, a subtype, a length, some other stuff and the
 * data blob, which depends on the event. The header is 'struct
 * uwb_event'; for payloads, see 'struct uwbd_evt_*'.
 *
 * EVENT HANDLER TABLES
 *
 * To find a handling function for an event, the type is used to index
 * a subtype-table in the type-table. The subtype-table is indexed
 * with the subtype to get the function that handles the event. Start
 * with the main type-table 'uwbd_evt_type_handler'.
 *
 * DEVICES
 *
 * Devices are created when a bunch of beacons have been received and
 * it is stablished that the device has stable radio presence. CREATED
 * only, not configured. Devices are ONLY configured when an
 * Application-Specific IE Probe is receieved, in which the device
 * declares which Protocol ID it groks. Then the device is CONFIGURED
 * (and the driver->probe() stuff of the device model is invoked).
 *
 * Devices are considered disconnected when a certain number of
 * beacons are not received in an amount of time.
 *
 * Handler functions are called normally uwbd_evt_handle_*().
 */
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/freezer.h>

#include "uwb-internal.h"

/*
 * UWBD Event handler function signature
 *
 * Return !0 if the event needs not to be freed (ie the handler
 * takes/took care of it). 0 means the daemon code will free the
 * event.
 *
 * @evt->rc is already referenced and guaranteed to exist. See
 * uwb_evt_handle().
 */
typedef int (*uwbd_evt_handler_f)(struct uwb_event *);

/**
 * Properties of a UWBD event
 *
 * @handler:    the function that will handle this event
 * @name:       text name of event
 */
struct uwbd_event {
	uwbd_evt_handler_f handler;
	const char *name;
};

/* Table of handlers for and properties of the UWBD Radio Control Events */
static struct uwbd_event uwbd_urc_events[] = {
	[UWB_RC_EVT_IE_RCV] = {
		.handler = uwbd_evt_handle_rc_ie_rcv,
		.name = "IE_RECEIVED"
	},
	[UWB_RC_EVT_BEACON] = {
		.handler = uwbd_evt_handle_rc_beacon,
		.name = "BEACON_RECEIVED"
	},
	[UWB_RC_EVT_BEACON_SIZE] = {
		.handler = uwbd_evt_handle_rc_beacon_size,
		.name = "BEACON_SIZE_CHANGE"
	},
	[UWB_RC_EVT_BPOIE_CHANGE] = {
		.handler = uwbd_evt_handle_rc_bpoie_change,
		.name = "BPOIE_CHANGE"
	},
	[UWB_RC_EVT_BP_SLOT_CHANGE] = {
		.handler = uwbd_evt_handle_rc_bp_slot_change,
		.name = "BP_SLOT_CHANGE"
	},
	[UWB_RC_EVT_DRP_AVAIL] = {
		.handler = uwbd_evt_handle_rc_drp_avail,
		.name = "DRP_AVAILABILITY_CHANGE"
	},
	[UWB_RC_EVT_DRP] = {
		.handler = uwbd_evt_handle_rc_drp,
		.name = "DRP"
	},
	[UWB_RC_EVT_DEV_ADDR_CONFLICT] = {
		.handler = uwbd_evt_handle_rc_dev_addr_conflict,
		.name = "DEV_ADDR_CONFLICT",
	},
};


struct uwbd_evt_type_handler {
	const char *name;
	struct uwbd_event *uwbd_events;
	size_t size;
};

/* Table of handlers for each UWBD Event type. */
static struct uwbd_evt_type_handler uwbd_urc_evt_type_handlers[] = {
	[UWB_RC_CET_GENERAL] = {
		.name        = "URC",
		.uwbd_events = uwbd_urc_events,
		.size        = ARRAY_SIZE(uwbd_urc_events),
	},
};

static const struct uwbd_event uwbd_message_handlers[] = {
	[UWB_EVT_MSG_RESET] = {
		.handler = uwbd_msg_handle_reset,
		.name = "reset",
	},
};

/*
 * Handle an URC event passed to the UWB Daemon
 *
 * @evt: the event to handle
 * @returns: 0 if the event can be kfreed, !0 on the contrary
 *           (somebody else took ownership) [coincidentally, returning
 *           a <0 errno code will free it :)].
 *
 * Looks up the two indirection tables (one for the type, one for the
 * subtype) to decide which function handles it and then calls the
 * handler.
 *
 * The event structure passed to the event handler has the radio
 * controller in @evt->rc referenced. The reference will be dropped
 * once the handler returns, so if it needs it for longer (async),
 * it'll need to take another one.
 */
static
int uwbd_event_handle_urc(struct uwb_event *evt)
{
	int result = -EINVAL;
	struct uwbd_evt_type_handler *type_table;
	uwbd_evt_handler_f handler;
	u8 type, context;
	u16 event;

	type = evt->notif.rceb->bEventType;
	event = le16_to_cpu(evt->notif.rceb->wEvent);
	context = evt->notif.rceb->bEventContext;

	if (type >= ARRAY_SIZE(uwbd_urc_evt_type_handlers))
		goto out;
	type_table = &uwbd_urc_evt_type_handlers[type];
	if (type_table->uwbd_events == NULL)
		goto out;
	if (event >= type_table->size)
		goto out;
	handler = type_table->uwbd_events[event].handler;
	if (handler == NULL)
		goto out;

	result = (*handler)(evt);
out:
	if (result < 0)
		dev_err(&evt->rc->uwb_dev.dev,
			"UWBD: event 0x%02x/%04x/%02x, handling failed: %d\n",
			type, event, context, result);
	return result;
}

static void uwbd_event_handle_message(struct uwb_event *evt)
{
	struct uwb_rc *rc;
	int result;

	rc = evt->rc;

	if (evt->message < 0 || evt->message >= ARRAY_SIZE(uwbd_message_handlers)) {
		dev_err(&rc->uwb_dev.dev, "UWBD: invalid message type %d\n", evt->message);
		return;
	}

	result = uwbd_message_handlers[evt->message].handler(evt);
	if (result < 0)
		dev_err(&rc->uwb_dev.dev, "UWBD: '%s' message failed: %d\n",
			uwbd_message_handlers[evt->message].name, result);
}

static void uwbd_event_handle(struct uwb_event *evt)
{
	struct uwb_rc *rc;
	int should_keep;

	rc = evt->rc;

	if (rc->ready) {
		switch (evt->type) {
		case UWB_EVT_TYPE_NOTIF:
			should_keep = uwbd_event_handle_urc(evt);
			if (should_keep <= 0)
				kfree(evt->notif.rceb);
			break;
		case UWB_EVT_TYPE_MSG:
			uwbd_event_handle_message(evt);
			break;
		default:
			dev_err(&rc->uwb_dev.dev, "UWBD: invalid event type %d\n", evt->type);
			break;
		}
	}

	__uwb_rc_put(rc);	/* for the __uwb_rc_get() in uwb_rc_notif_cb() */
}

/**
 * UWB Daemon
 *
 * Listens to all UWB notifications and takes care to track the state
 * of the UWB neighboorhood for the kernel. When we do a run, we
 * spinlock, move the list to a private copy and release the
 * lock. Hold it as little as possible. Not a conflict: it is
 * guaranteed we own the events in the private list.
 *
 * FIXME: should change so we don't have a 1HZ timer all the time, but
 *        only if there are devices.
 */
static int uwbd(void *param)
{
	struct uwb_rc *rc = param;
	unsigned long flags;
	struct uwb_event *evt;
	int should_stop = 0;

	while (1) {
		wait_event_interruptible_timeout(
			rc->uwbd.wq,
			!list_empty(&rc->uwbd.event_list)
			  || (should_stop = kthread_should_stop()),
			HZ);
		if (should_stop)
			break;
		try_to_freeze();

		spin_lock_irqsave(&rc->uwbd.event_list_lock, flags);
		if (!list_empty(&rc->uwbd.event_list)) {
			evt = list_first_entry(&rc->uwbd.event_list, struct uwb_event, list_node);
			list_del(&evt->list_node);
		} else
			evt = NULL;
		spin_unlock_irqrestore(&rc->uwbd.event_list_lock, flags);

		if (evt) {
			uwbd_event_handle(evt);
			kfree(evt);
		}

		uwb_beca_purge(rc);	/* Purge devices that left */
	}
	return 0;
}


/** Start the UWB daemon */
void uwbd_start(struct uwb_rc *rc)
{
	rc->uwbd.task = kthread_run(uwbd, rc, "uwbd");
	if (rc->uwbd.task == NULL)
		printk(KERN_ERR "UWB: Cannot start management daemon; "
		       "UWB won't work\n");
	else
		rc->uwbd.pid = rc->uwbd.task->pid;
}

/* Stop the UWB daemon and free any unprocessed events */
void uwbd_stop(struct uwb_rc *rc)
{
	kthread_stop(rc->uwbd.task);
	uwbd_flush(rc);
}

/*
 * Queue an event for the management daemon
 *
 * When some lower layer receives an event, it uses this function to
 * push it forward to the UWB daemon.
 *
 * Once you pass the event, you don't own it any more, but the daemon
 * does. It will uwb_event_free() it when done, so make sure you
 * uwb_event_alloc()ed it or bad things will happen.
 *
 * If the daemon is not running, we just free the event.
 */
void uwbd_event_queue(struct uwb_event *evt)
{
	struct uwb_rc *rc = evt->rc;
	unsigned long flags;

	spin_lock_irqsave(&rc->uwbd.event_list_lock, flags);
	if (rc->uwbd.pid != 0) {
		list_add(&evt->list_node, &rc->uwbd.event_list);
		wake_up_all(&rc->uwbd.wq);
	} else {
		__uwb_rc_put(evt->rc);
		if (evt->type == UWB_EVT_TYPE_NOTIF)
			kfree(evt->notif.rceb);
		kfree(evt);
	}
	spin_unlock_irqrestore(&rc->uwbd.event_list_lock, flags);
	return;
}

void uwbd_flush(struct uwb_rc *rc)
{
	struct uwb_event *evt, *nxt;

	spin_lock_irq(&rc->uwbd.event_list_lock);
	list_for_each_entry_safe(evt, nxt, &rc->uwbd.event_list, list_node) {
		if (evt->rc == rc) {
			__uwb_rc_put(rc);
			list_del(&evt->list_node);
			if (evt->type == UWB_EVT_TYPE_NOTIF)
				kfree(evt->notif.rceb);
			kfree(evt);
		}
	}
	spin_unlock_irq(&rc->uwbd.event_list_lock);
}
Commit	Line	Data
183b9b59 IPG	1	/*
	2	* Ultra Wide Band
	3	* Neighborhood Management Daemon
	4	*
	5	* Copyright (C) 2005-2006 Intel Corporation
	6	* Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License version
	10	* 2 as published by the Free Software Foundation.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	20	* 02110-1301, USA.
	21	*
	22	*
	23	* This daemon takes care of maintaing information that describes the
	24	* UWB neighborhood that the radios in this machine can see. It also
	25	* keeps a tab of which devices are visible, makes sure each HC sits
	26	* on a different channel to avoid interfering, etc.
	27	*
	28	* Different drivers (radio controller, device, any API in general)
	29	* communicate with this daemon through an event queue. Daemon wakes
	30	* up, takes a list of events and handles them one by one; handling
	31	* function is extracted from a table based on the event's type and
	32	* subtype. Events are freed only if the handling function says so.
	33	*
	34	* . Lock protecting the event list has to be an spinlock and locked
	35	* with IRQSAVE because it might be called from an interrupt
	36	* context (ie: when events arrive and the notification drops
	37	* down from the ISR).
	38	*
	39	* . UWB radio controller drivers queue events to the daemon using
	40	* uwbd_event_queue(). They just get the event, chew it to make it
	41	* look like UWBD likes it and pass it in a buffer allocated with
	42	* uwb_event_alloc().
	43	*
	44	* EVENTS
	45	*
1537a363	46	* Events have a type, a subtype, a length, some other stuff and the
183b9b59 IPG	47	* data blob, which depends on the event. The header is 'struct
	48	* uwb_event'; for payloads, see 'struct uwbd_evt_*'.
	49	*
	50	* EVENT HANDLER TABLES
	51	*
	52	* To find a handling function for an event, the type is used to index
	53	* a subtype-table in the type-table. The subtype-table is indexed
	54	* with the subtype to get the function that handles the event. Start
	55	* with the main type-table 'uwbd_evt_type_handler'.
	56	*
	57	* DEVICES
	58	*
	59	* Devices are created when a bunch of beacons have been received and
	60	* it is stablished that the device has stable radio presence. CREATED
	61	* only, not configured. Devices are ONLY configured when an
	62	* Application-Specific IE Probe is receieved, in which the device
	63	* declares which Protocol ID it groks. Then the device is CONFIGURED
	64	* (and the driver->probe() stuff of the device model is invoked).
	65	*
	66	* Devices are considered disconnected when a certain number of
	67	* beacons are not received in an amount of time.
	68	*
	69	* Handler functions are called normally uwbd_evt_handle_*().
	70	*/
183b9b59 IPG	71	#include <linux/kthread.h>
	72	#include <linux/module.h>
	73	#include <linux/freezer.h>
183b9b59	74
bce83697	75	#include "uwb-internal.h"
183b9b59	76
bce83697	77	/*
183b9b59 IPG	78	* UWBD Event handler function signature
	79	*
	80	* Return !0 if the event needs not to be freed (ie the handler
	81	* takes/took care of it). 0 means the daemon code will free the
	82	* event.
	83	*
	84	* @evt->rc is already referenced and guaranteed to exist. See
	85	* uwb_evt_handle().
	86	*/
	87	typedef int (uwbd_evt_handler_f)(struct uwb_event );
	88
	89	/**
	90	* Properties of a UWBD event
	91	*
	92	* @handler: the function that will handle this event
	93	* @name: text name of event
	94	*/
	95	struct uwbd_event {
	96	uwbd_evt_handler_f handler;
	97	const char *name;
	98	};
	99
bce83697 DV	100	/* Table of handlers for and properties of the UWBD Radio Control Events */
bce83697 DV	101	static struct uwbd_event uwbd_urc_events[] = {
c5995bd2 SP	102	[UWB_RC_EVT_IE_RCV] = {
	103	.handler = uwbd_evt_handle_rc_ie_rcv,
	104	.name = "IE_RECEIVED"
	105	},
183b9b59 IPG	106	[UWB_RC_EVT_BEACON] = {
	107	.handler = uwbd_evt_handle_rc_beacon,
	108	.name = "BEACON_RECEIVED"
	109	},
	110	[UWB_RC_EVT_BEACON_SIZE] = {
	111	.handler = uwbd_evt_handle_rc_beacon_size,
	112	.name = "BEACON_SIZE_CHANGE"
	113	},
	114	[UWB_RC_EVT_BPOIE_CHANGE] = {
	115	.handler = uwbd_evt_handle_rc_bpoie_change,
	116	.name = "BPOIE_CHANGE"
	117	},
	118	[UWB_RC_EVT_BP_SLOT_CHANGE] = {
	119	.handler = uwbd_evt_handle_rc_bp_slot_change,
	120	.name = "BP_SLOT_CHANGE"
	121	},
	122	[UWB_RC_EVT_DRP_AVAIL] = {
	123	.handler = uwbd_evt_handle_rc_drp_avail,
	124	.name = "DRP_AVAILABILITY_CHANGE"
	125	},
	126	[UWB_RC_EVT_DRP] = {
	127	.handler = uwbd_evt_handle_rc_drp,
	128	.name = "DRP"
	129	},
	130	[UWB_RC_EVT_DEV_ADDR_CONFLICT] = {
	131	.handler = uwbd_evt_handle_rc_dev_addr_conflict,
	132	.name = "DEV_ADDR_CONFLICT",
	133	},
	134	};
	135
	136
	137
	138	struct uwbd_evt_type_handler {
	139	const char *name;
	140	struct uwbd_event *uwbd_events;
	141	size_t size;
	142	};
	143
bce83697 DV	144	/* Table of handlers for each UWBD Event type. */
	145	static struct uwbd_evt_type_handler uwbd_urc_evt_type_handlers[] = {
	146	[UWB_RC_CET_GENERAL] = {
	147	.name = "URC",
	148	.uwbd_events = uwbd_urc_events,
	149	.size = ARRAY_SIZE(uwbd_urc_events),
	150	},
183b9b59 IPG	151	};
183b9b59 IPG	152
183b9b59 IPG	153	static const struct uwbd_event uwbd_message_handlers[] = {
	154	[UWB_EVT_MSG_RESET] = {
	155	.handler = uwbd_msg_handle_reset,
	156	.name = "reset",
	157	},
	158	};
	159
bce83697	160	/*
183b9b59 IPG	161	* Handle an URC event passed to the UWB Daemon
	162	*
	163	* @evt: the event to handle
	164	* @returns: 0 if the event can be kfreed, !0 on the contrary
	165	* (somebody else took ownership) [coincidentally, returning
	166	* a <0 errno code will free it :)].
	167	*
	168	* Looks up the two indirection tables (one for the type, one for the
	169	* subtype) to decide which function handles it and then calls the
	170	* handler.
	171	*
	172	* The event structure passed to the event handler has the radio
	173	* controller in @evt->rc referenced. The reference will be dropped
	174	* once the handler returns, so if it needs it for longer (async),
	175	* it'll need to take another one.
	176	*/
	177	static
	178	int uwbd_event_handle_urc(struct uwb_event *evt)
	179	{
bce83697	180	int result = -EINVAL;
183b9b59 IPG	181	struct uwbd_evt_type_handler *type_table;
	182	uwbd_evt_handler_f handler;
	183	u8 type, context;
	184	u16 event;
	185
	186	type = evt->notif.rceb->bEventType;
	187	event = le16_to_cpu(evt->notif.rceb->wEvent);
	188	context = evt->notif.rceb->bEventContext;
	189
3fafdd7c	190	if (type >= ARRAY_SIZE(uwbd_urc_evt_type_handlers))
bce83697 DV	191	goto out;
	192	type_table = &uwbd_urc_evt_type_handlers[type];
	193	if (type_table->uwbd_events == NULL)
	194	goto out;
3fafdd7c	195	if (event >= type_table->size)
bce83697	196	goto out;
183b9b59	197	handler = type_table->uwbd_events[event].handler;
bce83697 DV	198	if (handler == NULL)
	199	goto out;
	200
	201	result = (*handler)(evt);
	202	out:
	203	if (result < 0)
	204	dev_err(&evt->rc->uwb_dev.dev,
	205	"UWBD: event 0x%02x/%04x/%02x, handling failed: %d\n",
	206	type, event, context, result);
	207	return result;
183b9b59 IPG	208	}
	209
	210	static void uwbd_event_handle_message(struct uwb_event *evt)
	211	{
	212	struct uwb_rc *rc;
	213	int result;
	214
	215	rc = evt->rc;
	216
	217	if (evt->message < 0 \|\| evt->message >= ARRAY_SIZE(uwbd_message_handlers)) {
	218	dev_err(&rc->uwb_dev.dev, "UWBD: invalid message type %d\n", evt->message);
	219	return;
	220	}
	221
183b9b59 IPG	222	result = uwbd_message_handlers[evt->message].handler(evt);
	223	if (result < 0)
	224	dev_err(&rc->uwb_dev.dev, "UWBD: '%s' message failed: %d\n",
	225	uwbd_message_handlers[evt->message].name, result);
183b9b59 IPG	226	}
	227
	228	static void uwbd_event_handle(struct uwb_event *evt)
	229	{
	230	struct uwb_rc *rc;
	231	int should_keep;
	232
	233	rc = evt->rc;
	234
	235	if (rc->ready) {
	236	switch (evt->type) {
	237	case UWB_EVT_TYPE_NOTIF:
	238	should_keep = uwbd_event_handle_urc(evt);
	239	if (should_keep <= 0)
	240	kfree(evt->notif.rceb);
	241	break;
	242	case UWB_EVT_TYPE_MSG:
	243	uwbd_event_handle_message(evt);
	244	break;
	245	default:
	246	dev_err(&rc->uwb_dev.dev, "UWBD: invalid event type %d\n", evt->type);
	247	break;
	248	}
	249	}
	250
	251	__uwb_rc_put(rc); /* for the __uwb_rc_get() in uwb_rc_notif_cb() */
	252	}
183b9b59 IPG	253
	254	/**
	255	* UWB Daemon
	256	*
	257	* Listens to all UWB notifications and takes care to track the state
	258	* of the UWB neighboorhood for the kernel. When we do a run, we
	259	* spinlock, move the list to a private copy and release the
	260	* lock. Hold it as little as possible. Not a conflict: it is
	261	* guaranteed we own the events in the private list.
	262	*
	263	* FIXME: should change so we don't have a 1HZ timer all the time, but
	264	* only if there are devices.
	265	*/
fec1a593	266	static int uwbd(void *param)
183b9b59	267	{
fec1a593	268	struct uwb_rc *rc = param;
183b9b59	269	unsigned long flags;
fec1a593	270	struct uwb_event *evt;
183b9b59	271	int should_stop = 0;
fec1a593	272
183b9b59 IPG	273	while (1) {
183b9b59 IPG	274	wait_event_interruptible_timeout(
fec1a593 SP	275	rc->uwbd.wq,
fec1a593 SP	276	!list_empty(&rc->uwbd.event_list)
183b9b59 IPG	277	\|\| (should_stop = kthread_should_stop()),
	278	HZ);
	279	if (should_stop)
	280	break;
	281	try_to_freeze();
	282
fec1a593 SP	283	spin_lock_irqsave(&rc->uwbd.event_list_lock, flags);
	284	if (!list_empty(&rc->uwbd.event_list)) {
	285	evt = list_first_entry(&rc->uwbd.event_list, struct uwb_event, list_node);
183b9b59	286	list_del(&evt->list_node);
fec1a593 SP	287	} else
	288	evt = NULL;
	289	spin_unlock_irqrestore(&rc->uwbd.event_list_lock, flags);
	290
	291	if (evt) {
183b9b59 IPG	292	uwbd_event_handle(evt);
	293	kfree(evt);
	294	}
183b9b59	295
fec1a593	296	uwb_beca_purge(rc); /* Purge devices that left */
183b9b59 IPG	297	}
	298	return 0;
	299	}
	300
	301
	302	/** Start the UWB daemon */
fec1a593	303	void uwbd_start(struct uwb_rc *rc)
183b9b59	304	{
fec1a593 SP	305	rc->uwbd.task = kthread_run(uwbd, rc, "uwbd");
fec1a593 SP	306	if (rc->uwbd.task == NULL)
183b9b59 IPG	307	printk(KERN_ERR "UWB: Cannot start management daemon; "
	308	"UWB won't work\n");
	309	else
fec1a593	310	rc->uwbd.pid = rc->uwbd.task->pid;
183b9b59 IPG	311	}
	312
	313	/* Stop the UWB daemon and free any unprocessed events */
fec1a593	314	void uwbd_stop(struct uwb_rc *rc)
183b9b59	315	{
fec1a593 SP	316	kthread_stop(rc->uwbd.task);
fec1a593 SP	317	uwbd_flush(rc);
183b9b59 IPG	318	}
	319
	320	/*
	321	* Queue an event for the management daemon
	322	*
	323	* When some lower layer receives an event, it uses this function to
	324	* push it forward to the UWB daemon.
	325	*
	326	* Once you pass the event, you don't own it any more, but the daemon
	327	* does. It will uwb_event_free() it when done, so make sure you
	328	* uwb_event_alloc()ed it or bad things will happen.
	329	*
	330	* If the daemon is not running, we just free the event.
	331	*/
	332	void uwbd_event_queue(struct uwb_event *evt)
	333	{
fec1a593	334	struct uwb_rc *rc = evt->rc;
183b9b59	335	unsigned long flags;
fec1a593 SP	336
	337	spin_lock_irqsave(&rc->uwbd.event_list_lock, flags);
	338	if (rc->uwbd.pid != 0) {
	339	list_add(&evt->list_node, &rc->uwbd.event_list);
	340	wake_up_all(&rc->uwbd.wq);
183b9b59 IPG	341	} else {
	342	__uwb_rc_put(evt->rc);
	343	if (evt->type == UWB_EVT_TYPE_NOTIF)
	344	kfree(evt->notif.rceb);
	345	kfree(evt);
	346	}
fec1a593	347	spin_unlock_irqrestore(&rc->uwbd.event_list_lock, flags);
183b9b59 IPG	348	return;
	349	}
	350
	351	void uwbd_flush(struct uwb_rc *rc)
	352	{
	353	struct uwb_event evt, nxt;
	354
fec1a593 SP	355	spin_lock_irq(&rc->uwbd.event_list_lock);
fec1a593 SP	356	list_for_each_entry_safe(evt, nxt, &rc->uwbd.event_list, list_node) {
183b9b59 IPG	357	if (evt->rc == rc) {
	358	__uwb_rc_put(rc);
	359	list_del(&evt->list_node);
	360	if (evt->type == UWB_EVT_TYPE_NOTIF)
	361	kfree(evt->notif.rceb);
	362	kfree(evt);
	363	}
	364	}
fec1a593	365	spin_unlock_irq(&rc->uwbd.event_list_lock);
183b9b59	366	}