/*
* 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 I2O device class id matches 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
* @c: newly added controller
*
* 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
* @c: controller that is being removed
*
* 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
* @i2o_dev: newly added I2O device
*
* 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
* @i2o_dev: device that is being removed
*
* 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 frees 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);
