[linux-2.6-block.git] / drivers / message / i2o / driver.c

/*
 *	Functions to handle I2O drivers (OSMs) and I2O bus type for sysfs
 *
 *	Copyright (C) 2004	Markus Lidel <Markus.Lidel@shadowconnect.com>
 *
 *	This program is free software; you can redistribute it and/or modify it
 *	under the terms of the GNU General Public License as published by the
 *	Free Software Foundation; either version 2 of the License, or (at your
 *	option) any later version.
 *
 *	Fixes/additions:
 *		Markus Lidel <Markus.Lidel@shadowconnect.com>
 *			initial version.
 */

#include <linux/device.h>
#include <linux/module.h>
#include <linux/rwsem.h>
#include <linux/i2o.h>
#include "core.h"

#define OSM_NAME	"i2o"

/* max_drivers - Maximum I2O drivers (OSMs) which could be registered */
static unsigned int i2o_max_drivers = I2O_MAX_DRIVERS;
module_param_named(max_drivers, i2o_max_drivers, uint, 0);
MODULE_PARM_DESC(max_drivers, "maximum number of OSM's to support");

/* I2O drivers lock and array */
static spinlock_t i2o_drivers_lock;
static struct i2o_driver **i2o_drivers;

/**
 *	i2o_bus_match - Tell if a I2O device class id match the class ids of
 *			the I2O driver (OSM)
 *
 *	@dev: device which should be verified
 *	@drv: the driver to match against
 *
 *	Used by the bus to check if the driver wants to handle the device.
 *
 *	Returns 1 if the class ids of the driver match the class id of the
 *	device, otherwise 0.
 */
static int i2o_bus_match(struct device *dev, struct device_driver *drv)
{
	struct i2o_device *i2o_dev = to_i2o_device(dev);
	struct i2o_driver *i2o_drv = to_i2o_driver(drv);
	struct i2o_class_id *ids = i2o_drv->classes;

	if (ids)
		while (ids->class_id != I2O_CLASS_END) {
			if (ids->class_id == i2o_dev->lct_data.class_id)
				return 1;
			ids++;
		}
	return 0;
};

/* I2O bus type */
struct bus_type i2o_bus_type = {
	.name = "i2o",
	.match = i2o_bus_match,
};

/**
 *	i2o_driver_register - Register a I2O driver (OSM) in the I2O core
 *	@drv: I2O driver which should be registered
 *
 *	Registers the OSM drv in the I2O core and creates an event queues if
 *	necessary.
 *
 *	Returns 0 on success or negative error code on failure.
 */
int i2o_driver_register(struct i2o_driver *drv)
{
	struct i2o_controller *c;
	int i;
	int rc = 0;
	unsigned long flags;

	osm_debug("Register driver %s\n", drv->name);

	if (drv->event) {
		drv->event_queue = create_workqueue(drv->name);
		if (!drv->event_queue) {
			osm_err("Could not initialize event queue for driver "
				"%s\n", drv->name);
			return -EFAULT;
		}
		osm_debug("Event queue initialized for driver %s\n", drv->name);
	} else
		drv->event_queue = NULL;

	drv->driver.name = drv->name;
	drv->driver.bus = &i2o_bus_type;

	spin_lock_irqsave(&i2o_drivers_lock, flags);

	for (i = 0; i2o_drivers[i]; i++)
		if (i >= i2o_max_drivers) {
			osm_err("too many drivers registered, increase "
				"max_drivers\n");
			spin_unlock_irqrestore(&i2o_drivers_lock, flags);
			return -EFAULT;
		}

	drv->context = i;
	i2o_drivers[i] = drv;

	spin_unlock_irqrestore(&i2o_drivers_lock, flags);

	osm_debug("driver %s gets context id %d\n", drv->name, drv->context);

	list_for_each_entry(c, &i2o_controllers, list) {
		struct i2o_device *i2o_dev;

		i2o_driver_notify_controller_add(drv, c);
		list_for_each_entry(i2o_dev, &c->devices, list)
			i2o_driver_notify_device_add(drv, i2o_dev);
	}


	rc = driver_register(&drv->driver);
	if (rc)
		destroy_workqueue(drv->event_queue);

	return rc;
};

/**
 *	i2o_driver_unregister - Unregister a I2O driver (OSM) from the I2O core
 *	@drv: I2O driver which should be unregistered
 *
 *	Unregisters the OSM drv from the I2O core and cleanup event queues if
 *	necessary.
 */
void i2o_driver_unregister(struct i2o_driver *drv)
{
	struct i2o_controller *c;
	unsigned long flags;

	osm_debug("unregister driver %s\n", drv->name);

	driver_unregister(&drv->driver);

	list_for_each_entry(c, &i2o_controllers, list) {
		struct i2o_device *i2o_dev;

		list_for_each_entry(i2o_dev, &c->devices, list)
		    i2o_driver_notify_device_remove(drv, i2o_dev);

		i2o_driver_notify_controller_remove(drv, c);
	}

	spin_lock_irqsave(&i2o_drivers_lock, flags);
	i2o_drivers[drv->context] = NULL;
	spin_unlock_irqrestore(&i2o_drivers_lock, flags);

	if (drv->event_queue) {
		destroy_workqueue(drv->event_queue);
		drv->event_queue = NULL;
		osm_debug("event queue removed for %s\n", drv->name);
	}
};

/**
 *	i2o_driver_dispatch - dispatch an I2O reply message
 *	@c: I2O controller of the message
 *	@m: I2O message number
 *	@msg: I2O message to be delivered
 *
 *	The reply is delivered to the driver from which the original message
 *	was. This function is only called from interrupt context.
 *
 *	Returns 0 on success and the message should not be flushed. Returns > 0
 *	on success and if the message should be flushed afterwords. Returns
 *	negative error code on failure (the message will be flushed too).
 */
int i2o_driver_dispatch(struct i2o_controller *c, u32 m)
{
	struct i2o_driver *drv;
	struct i2o_message *msg = i2o_msg_out_to_virt(c, m);
	u32 context = le32_to_cpu(msg->u.s.icntxt);
	unsigned long flags;

	if (unlikely(context >= i2o_max_drivers)) {
		osm_warn("%s: Spurious reply to unknown driver %d\n", c->name,
			 context);
		return -EIO;
	}

	spin_lock_irqsave(&i2o_drivers_lock, flags);
	drv = i2o_drivers[context];
	spin_unlock_irqrestore(&i2o_drivers_lock, flags);

	if (unlikely(!drv)) {
		osm_warn("%s: Spurious reply to unknown driver %d\n", c->name,
			 context);
		return -EIO;
	}

	if ((le32_to_cpu(msg->u.head[1]) >> 24) == I2O_CMD_UTIL_EVT_REGISTER) {
		struct i2o_device *dev, *tmp;
		struct i2o_event *evt;
		u16 size;
		u16 tid = le32_to_cpu(msg->u.head[1]) & 0xfff;

		osm_debug("event received from device %d\n", tid);

		if (!drv->event)
			return -EIO;

		/* cut of header from message size (in 32-bit words) */
		size = (le32_to_cpu(msg->u.head[0]) >> 16) - 5;

		evt = kmalloc(size * 4 + sizeof(*evt), GFP_ATOMIC | __GFP_ZERO);
		if (!evt)
			return -ENOMEM;

		evt->size = size;
		evt->tcntxt = le32_to_cpu(msg->u.s.tcntxt);
		evt->event_indicator = le32_to_cpu(msg->body[0]);
		memcpy(&evt->tcntxt, &msg->u.s.tcntxt, size * 4);

		list_for_each_entry_safe(dev, tmp, &c->devices, list)
		    if (dev->lct_data.tid == tid) {
			evt->i2o_dev = dev;
			break;
		}

		INIT_WORK(&evt->work, (void (*)(void *))drv->event, evt);
		queue_work(drv->event_queue, &evt->work);
		return 1;
	}

	if (unlikely(!drv->reply)) {
		osm_debug("%s: Reply to driver %s, but no reply function"
			  " defined!\n", c->name, drv->name);
		return -EIO;
	}

	return drv->reply(c, m, msg);
}

/**
 *	i2o_driver_notify_controller_add_all - Send notify of added controller
 *					       to all I2O drivers
 *
 *	Send notifications to all registered drivers that a new controller was
 *	added.
 */
void i2o_driver_notify_controller_add_all(struct i2o_controller *c)
{
	int i;
	struct i2o_driver *drv;

	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
		drv = i2o_drivers[i];

		if (drv)
			i2o_driver_notify_controller_add(drv, c);
	}
}

/**
 *	i2o_driver_notify_controller_remove_all - Send notify of removed
 *						  controller to all I2O drivers
 *
 *	Send notifications to all registered drivers that a controller was
 *	removed.
 */
void i2o_driver_notify_controller_remove_all(struct i2o_controller *c)
{
	int i;
	struct i2o_driver *drv;

	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
		drv = i2o_drivers[i];

		if (drv)
			i2o_driver_notify_controller_remove(drv, c);
	}
}

/**
 *	i2o_driver_notify_device_add_all - Send notify of added device to all
 *					   I2O drivers
 *
 *	Send notifications to all registered drivers that a device was added.
 */
void i2o_driver_notify_device_add_all(struct i2o_device *i2o_dev)
{
	int i;
	struct i2o_driver *drv;

	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
		drv = i2o_drivers[i];

		if (drv)
			i2o_driver_notify_device_add(drv, i2o_dev);
	}
}

/**
 *	i2o_driver_notify_device_remove_all - Send notify of removed device to
 *					      all I2O drivers
 *
 *	Send notifications to all registered drivers that a device was removed.
 */
void i2o_driver_notify_device_remove_all(struct i2o_device *i2o_dev)
{
	int i;
	struct i2o_driver *drv;

	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
		drv = i2o_drivers[i];

		if (drv)
			i2o_driver_notify_device_remove(drv, i2o_dev);
	}
}

/**
 *	i2o_driver_init - initialize I2O drivers (OSMs)
 *
 *	Registers the I2O bus and allocate memory for the array of OSMs.
 *
 *	Returns 0 on success or negative error code on failure.
 */
int __init i2o_driver_init(void)
{
	int rc = 0;

	spin_lock_init(&i2o_drivers_lock);

	if ((i2o_max_drivers < 2) || (i2o_max_drivers > 64) ||
	    ((i2o_max_drivers ^ (i2o_max_drivers - 1)) !=
	     (2 * i2o_max_drivers - 1))) {
		osm_warn("max_drivers set to %d, but must be >=2 and <= 64 and "
			 "a power of 2\n", i2o_max_drivers);
		i2o_max_drivers = I2O_MAX_DRIVERS;
	}
	osm_info("max drivers = %d\n", i2o_max_drivers);

	i2o_drivers =
	    kmalloc(i2o_max_drivers * sizeof(*i2o_drivers), GFP_KERNEL);
	if (!i2o_drivers)
		return -ENOMEM;

	memset(i2o_drivers, 0, i2o_max_drivers * sizeof(*i2o_drivers));

	rc = bus_register(&i2o_bus_type);

	if (rc < 0)
		kfree(i2o_drivers);

	return rc;
};

/**
 *	i2o_driver_exit - clean up I2O drivers (OSMs)
 *
 *	Unregisters the I2O bus and free driver array.
 */
void __exit i2o_driver_exit(void)
{
	bus_unregister(&i2o_bus_type);
	kfree(i2o_drivers);
};

EXPORT_SYMBOL(i2o_driver_register);
EXPORT_SYMBOL(i2o_driver_unregister);
EXPORT_SYMBOL(i2o_driver_notify_controller_add_all);
EXPORT_SYMBOL(i2o_driver_notify_controller_remove_all);
EXPORT_SYMBOL(i2o_driver_notify_device_add_all);
EXPORT_SYMBOL(i2o_driver_notify_device_remove_all);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Functions to handle I2O drivers (OSMs) and I2O bus type for sysfs
	3	*
	4	* Copyright (C) 2004 Markus Lidel <Markus.Lidel@shadowconnect.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License as published by the
	8	* Free Software Foundation; either version 2 of the License, or (at your
	9	* option) any later version.
	10	*
	11	* Fixes/additions:
	12	* Markus Lidel <Markus.Lidel@shadowconnect.com>
	13	* initial version.
	14	*/
	15
	16	#include <linux/device.h>
	17	#include <linux/module.h>
	18	#include <linux/rwsem.h>
	19	#include <linux/i2o.h>
9e87545f	20	#include "core.h"
1da177e4	21
f88e119c	22	#define OSM_NAME "i2o"
61fbfa81	23
1da177e4	24	/* max_drivers - Maximum I2O drivers (OSMs) which could be registered */
9e87545f	25	static unsigned int i2o_max_drivers = I2O_MAX_DRIVERS;
1da177e4 LT	26	module_param_named(max_drivers, i2o_max_drivers, uint, 0);
	27	MODULE_PARM_DESC(max_drivers, "maximum number of OSM's to support");
	28
	29	/* I2O drivers lock and array */
	30	static spinlock_t i2o_drivers_lock;
	31	static struct i2o_driver **i2o_drivers;
	32
	33	/**
	34	* i2o_bus_match - Tell if a I2O device class id match the class ids of
	35	* the I2O driver (OSM)
	36	*
	37	* @dev: device which should be verified
	38	* @drv: the driver to match against
	39	*
	40	* Used by the bus to check if the driver wants to handle the device.
	41	*
	42	* Returns 1 if the class ids of the driver match the class id of the
	43	* device, otherwise 0.
	44	*/
	45	static int i2o_bus_match(struct device dev, struct device_driver drv)
	46	{
	47	struct i2o_device *i2o_dev = to_i2o_device(dev);
	48	struct i2o_driver *i2o_drv = to_i2o_driver(drv);
	49	struct i2o_class_id *ids = i2o_drv->classes;
	50
	51	if (ids)
	52	while (ids->class_id != I2O_CLASS_END) {
	53	if (ids->class_id == i2o_dev->lct_data.class_id)
	54	return 1;
	55	ids++;
	56	}
	57	return 0;
	58	};
	59
	60	/* I2O bus type */
	61	struct bus_type i2o_bus_type = {
	62	.name = "i2o",
	63	.match = i2o_bus_match,
	64	};
	65
	66	/**
	67	* i2o_driver_register - Register a I2O driver (OSM) in the I2O core
	68	* @drv: I2O driver which should be registered
	69	*
	70	* Registers the OSM drv in the I2O core and creates an event queues if
	71	* necessary.
	72	*
	73	* Returns 0 on success or negative error code on failure.
	74	*/
	75	int i2o_driver_register(struct i2o_driver *drv)
	76	{
	77	struct i2o_controller *c;
	78	int i;
	79	int rc = 0;
	80	unsigned long flags;
	81
f88e119c	82	osm_debug("Register driver %s\n", drv->name);
1da177e4 LT	83
	84	if (drv->event) {
	85	drv->event_queue = create_workqueue(drv->name);
	86	if (!drv->event_queue) {
f88e119c ML	87	osm_err("Could not initialize event queue for driver "
f88e119c ML	88	"%s\n", drv->name);
1da177e4 LT	89	return -EFAULT;
1da177e4 LT	90	}
f88e119c	91	osm_debug("Event queue initialized for driver %s\n", drv->name);
1da177e4 LT	92	} else
	93	drv->event_queue = NULL;
	94
	95	drv->driver.name = drv->name;
	96	drv->driver.bus = &i2o_bus_type;
	97
	98	spin_lock_irqsave(&i2o_drivers_lock, flags);
	99
	100	for (i = 0; i2o_drivers[i]; i++)
	101	if (i >= i2o_max_drivers) {
f88e119c ML	102	osm_err("too many drivers registered, increase "
f88e119c ML	103	"max_drivers\n");
1da177e4 LT	104	spin_unlock_irqrestore(&i2o_drivers_lock, flags);
	105	return -EFAULT;
	106	}
	107
	108	drv->context = i;
	109	i2o_drivers[i] = drv;
	110
	111	spin_unlock_irqrestore(&i2o_drivers_lock, flags);
	112
f88e119c	113	osm_debug("driver %s gets context id %d\n", drv->name, drv->context);
1da177e4 LT	114
	115	list_for_each_entry(c, &i2o_controllers, list) {
	116	struct i2o_device *i2o_dev;
	117
	118	i2o_driver_notify_controller_add(drv, c);
	119	list_for_each_entry(i2o_dev, &c->devices, list)
	120	i2o_driver_notify_device_add(drv, i2o_dev);
	121	}
	122
	123
	124	rc = driver_register(&drv->driver);
	125	if (rc)
	126	destroy_workqueue(drv->event_queue);
	127
	128	return rc;
	129	};
	130
	131	/**
	132	* i2o_driver_unregister - Unregister a I2O driver (OSM) from the I2O core
	133	* @drv: I2O driver which should be unregistered
	134	*
	135	* Unregisters the OSM drv from the I2O core and cleanup event queues if
	136	* necessary.
	137	*/
	138	void i2o_driver_unregister(struct i2o_driver *drv)
	139	{
	140	struct i2o_controller *c;
	141	unsigned long flags;
	142
f88e119c	143	osm_debug("unregister driver %s\n", drv->name);
1da177e4 LT	144
	145	driver_unregister(&drv->driver);
	146
	147	list_for_each_entry(c, &i2o_controllers, list) {
	148	struct i2o_device *i2o_dev;
	149
	150	list_for_each_entry(i2o_dev, &c->devices, list)
	151	i2o_driver_notify_device_remove(drv, i2o_dev);
	152
	153	i2o_driver_notify_controller_remove(drv, c);
	154	}
	155
	156	spin_lock_irqsave(&i2o_drivers_lock, flags);
	157	i2o_drivers[drv->context] = NULL;
	158	spin_unlock_irqrestore(&i2o_drivers_lock, flags);
	159
	160	if (drv->event_queue) {
	161	destroy_workqueue(drv->event_queue);
	162	drv->event_queue = NULL;
f88e119c	163	osm_debug("event queue removed for %s\n", drv->name);
1da177e4 LT	164	}
	165	};
	166
	167	/**
	168	* i2o_driver_dispatch - dispatch an I2O reply message
	169	* @c: I2O controller of the message
	170	* @m: I2O message number
	171	* @msg: I2O message to be delivered
	172	*
	173	* The reply is delivered to the driver from which the original message
	174	* was. This function is only called from interrupt context.
	175	*
	176	* Returns 0 on success and the message should not be flushed. Returns > 0
	177	* on success and if the message should be flushed afterwords. Returns
	178	* negative error code on failure (the message will be flushed too).
	179	*/
f88e119c	180	int i2o_driver_dispatch(struct i2o_controller *c, u32 m)
1da177e4 LT	181	{
1da177e4 LT	182	struct i2o_driver *drv;
9e87545f ML	183	struct i2o_message *msg = i2o_msg_out_to_virt(c, m);
9e87545f ML	184	u32 context = le32_to_cpu(msg->u.s.icntxt);
f10378ff ML	185	unsigned long flags;
f10378ff ML	186
61fbfa81	187	if (unlikely(context >= i2o_max_drivers)) {
f88e119c ML	188	osm_warn("%s: Spurious reply to unknown driver %d\n", c->name,
f88e119c ML	189	context);
61fbfa81 ML	190	return -EIO;
61fbfa81 ML	191	}
1da177e4	192
f10378ff	193	spin_lock_irqsave(&i2o_drivers_lock, flags);
61fbfa81	194	drv = i2o_drivers[context];
f10378ff	195	spin_unlock_irqrestore(&i2o_drivers_lock, flags);
1da177e4	196
61fbfa81	197	if (unlikely(!drv)) {
f88e119c ML	198	osm_warn("%s: Spurious reply to unknown driver %d\n", c->name,
f88e119c ML	199	context);
61fbfa81 ML	200	return -EIO;
61fbfa81 ML	201	}
1da177e4	202
9e87545f	203	if ((le32_to_cpu(msg->u.head[1]) >> 24) == I2O_CMD_UTIL_EVT_REGISTER) {
61fbfa81 ML	204	struct i2o_device dev, tmp;
	205	struct i2o_event *evt;
	206	u16 size;
9e87545f	207	u16 tid = le32_to_cpu(msg->u.head[1]) & 0xfff;
1da177e4	208
61fbfa81	209	osm_debug("event received from device %d\n", tid);
1da177e4	210
f88e119c ML	211	if (!drv->event)
	212	return -EIO;
	213
61fbfa81	214	/* cut of header from message size (in 32-bit words) */
9e87545f	215	size = (le32_to_cpu(msg->u.head[0]) >> 16) - 5;
1da177e4	216
61fbfa81 ML	217	evt = kmalloc(size * 4 + sizeof(*evt), GFP_ATOMIC \| __GFP_ZERO);
	218	if (!evt)
	219	return -ENOMEM;
1da177e4	220
61fbfa81	221	evt->size = size;
9e87545f ML	222	evt->tcntxt = le32_to_cpu(msg->u.s.tcntxt);
	223	evt->event_indicator = le32_to_cpu(msg->body[0]);
	224	memcpy(&evt->tcntxt, &msg->u.s.tcntxt, size * 4);
1da177e4	225
61fbfa81 ML	226	list_for_each_entry_safe(dev, tmp, &c->devices, list)
	227	if (dev->lct_data.tid == tid) {
	228	evt->i2o_dev = dev;
	229	break;
1da177e4 LT	230	}
1da177e4 LT	231
61fbfa81 ML	232	INIT_WORK(&evt->work, (void ()(void ))drv->event, evt);
	233	queue_work(drv->event_queue, &evt->work);
	234	return 1;
	235	}
	236
	237	if (unlikely(!drv->reply)) {
f88e119c ML	238	osm_debug("%s: Reply to driver %s, but no reply function"
f88e119c ML	239	" defined!\n", c->name, drv->name);
1da177e4	240	return -EIO;
61fbfa81 ML	241	}
	242
	243	return drv->reply(c, m, msg);
1da177e4 LT	244	}
	245
	246	/**
	247	* i2o_driver_notify_controller_add_all - Send notify of added controller
	248	* to all I2O drivers
	249	*
	250	* Send notifications to all registered drivers that a new controller was
	251	* added.
	252	*/
	253	void i2o_driver_notify_controller_add_all(struct i2o_controller *c)
	254	{
	255	int i;
	256	struct i2o_driver *drv;
	257
	258	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
	259	drv = i2o_drivers[i];
	260
	261	if (drv)
	262	i2o_driver_notify_controller_add(drv, c);
	263	}
	264	}
	265
	266	/**
	267	* i2o_driver_notify_controller_remove_all - Send notify of removed
	268	* controller to all I2O drivers
	269	*
	270	* Send notifications to all registered drivers that a controller was
	271	* removed.
	272	*/
	273	void i2o_driver_notify_controller_remove_all(struct i2o_controller *c)
	274	{
	275	int i;
	276	struct i2o_driver *drv;
	277
	278	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
	279	drv = i2o_drivers[i];
	280
	281	if (drv)
	282	i2o_driver_notify_controller_remove(drv, c);
	283	}
	284	}
	285
	286	/**
	287	* i2o_driver_notify_device_add_all - Send notify of added device to all
	288	* I2O drivers
	289	*
	290	* Send notifications to all registered drivers that a device was added.
	291	*/
	292	void i2o_driver_notify_device_add_all(struct i2o_device *i2o_dev)
	293	{
	294	int i;
	295	struct i2o_driver *drv;
	296
	297	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
	298	drv = i2o_drivers[i];
	299
	300	if (drv)
	301	i2o_driver_notify_device_add(drv, i2o_dev);
	302	}
	303	}
	304
	305	/**
	306	* i2o_driver_notify_device_remove_all - Send notify of removed device to
	307	* all I2O drivers
308	*
309	* Send notifications to all registered drivers that a device was removed.
310	*/
311	void i2o_driver_notify_device_remove_all(struct i2o_device *i2o_dev)
312	{
313	int i;
314	struct i2o_driver *drv;
315
316	for (i = 0; i < I2O_MAX_DRIVERS; i++) {
317	drv = i2o_drivers[i];
318
319	if (drv)
320	i2o_driver_notify_device_remove(drv, i2o_dev);
321	}
322	}
323
324	/**
325	* i2o_driver_init - initialize I2O drivers (OSMs)
326	*
327	* Registers the I2O bus and allocate memory for the array of OSMs.
328	*
329	* Returns 0 on success or negative error code on failure.
330	*/
331	int __init i2o_driver_init(void)
332	{
333	int rc = 0;
334
335	spin_lock_init(&i2o_drivers_lock);
336
337	if ((i2o_max_drivers < 2) \|\| (i2o_max_drivers > 64) \|\|
338	((i2o_max_drivers ^ (i2o_max_drivers - 1)) !=
339	(2 * i2o_max_drivers - 1))) {
f88e119c ML	340	osm_warn("max_drivers set to %d, but must be >=2 and <= 64 and "
f88e119c ML	341	"a power of 2\n", i2o_max_drivers);
1da177e4 LT	342	i2o_max_drivers = I2O_MAX_DRIVERS;
1da177e4 LT	343	}
f88e119c	344	osm_info("max drivers = %d\n", i2o_max_drivers);
1da177e4 LT	345
	346	i2o_drivers =
	347	kmalloc(i2o_max_drivers * sizeof(*i2o_drivers), GFP_KERNEL);
	348	if (!i2o_drivers)
	349	return -ENOMEM;
	350
	351	memset(i2o_drivers, 0, i2o_max_drivers * sizeof(*i2o_drivers));
	352
	353	rc = bus_register(&i2o_bus_type);
	354
	355	if (rc < 0)
	356	kfree(i2o_drivers);
	357
	358	return rc;
	359	};
	360
	361	/**
	362	* i2o_driver_exit - clean up I2O drivers (OSMs)
	363	*
	364	* Unregisters the I2O bus and free driver array.
	365	*/
	366	void __exit i2o_driver_exit(void)
	367	{
	368	bus_unregister(&i2o_bus_type);
	369	kfree(i2o_drivers);
	370	};
	371
	372	EXPORT_SYMBOL(i2o_driver_register);
	373	EXPORT_SYMBOL(i2o_driver_unregister);
	374	EXPORT_SYMBOL(i2o_driver_notify_controller_add_all);
	375	EXPORT_SYMBOL(i2o_driver_notify_controller_remove_all);
	376	EXPORT_SYMBOL(i2o_driver_notify_device_add_all);
	377	EXPORT_SYMBOL(i2o_driver_notify_device_remove_all);