drivers/message/i2o/driver.c - arm/linux-arm64-legacy - Git at Google

 /*
  *	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 <linux/workqueue.h>
 #include <linux/string.h>
 #include <linux/slab.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,
 	.dev_attrs = i2o_device_attrs
 };

 /**
  *	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 = kzalloc(size * 4 + sizeof(*evt), GFP_ATOMIC);
 		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->data, &msg->body[1], 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, drv->event);
 		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 =
 	    kzalloc(i2o_max_drivers * sizeof(*i2o_drivers), GFP_KERNEL);
 	if (!i2o_drivers)
 		return -ENOMEM;

 	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);
	/*
	* 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 <linux/workqueue.h>
	#include <linux/string.h>
	#include <linux/slab.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,
	.dev_attrs = i2o_device_attrs
	};

	/**
	* 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 = kzalloc(size * 4 + sizeof(*evt), GFP_ATOMIC);
	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->data, &msg->body[1], 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, drv->event);
	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 =
	kzalloc(i2o_max_drivers * sizeof(*i2o_drivers), GFP_KERNEL);
	if (!i2o_drivers)
	return -ENOMEM;

	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);