acrn-kernel/drivers/rapidio/rio-driver.c

230 lines
6.0 KiB
C

/*
* RapidIO driver support
*
* Copyright 2005 MontaVista Software, Inc.
* Matt Porter <mporter@kernel.crashing.org>
*
* 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.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/rio.h>
#include <linux/rio_ids.h>
#include "rio.h"
/**
* rio_match_device - Tell if a RIO device has a matching RIO device id structure
* @id: the RIO device id structure to match against
* @rdev: the RIO device structure to match against
*
* Used from driver probe and bus matching to check whether a RIO device
* matches a device id structure provided by a RIO driver. Returns the
* matching &struct rio_device_id or %NULL if there is no match.
*/
static const struct rio_device_id *rio_match_device(const struct rio_device_id
*id,
const struct rio_dev *rdev)
{
while (id->vid || id->asm_vid) {
if (((id->vid == RIO_ANY_ID) || (id->vid == rdev->vid)) &&
((id->did == RIO_ANY_ID) || (id->did == rdev->did)) &&
((id->asm_vid == RIO_ANY_ID)
|| (id->asm_vid == rdev->asm_vid))
&& ((id->asm_did == RIO_ANY_ID)
|| (id->asm_did == rdev->asm_did)))
return id;
id++;
}
return NULL;
}
/**
* rio_dev_get - Increments the reference count of the RIO device structure
*
* @rdev: RIO device being referenced
*
* Each live reference to a device should be refcounted.
*
* Drivers for RIO devices should normally record such references in
* their probe() methods, when they bind to a device, and release
* them by calling rio_dev_put(), in their disconnect() methods.
*/
struct rio_dev *rio_dev_get(struct rio_dev *rdev)
{
if (rdev)
get_device(&rdev->dev);
return rdev;
}
/**
* rio_dev_put - Release a use of the RIO device structure
*
* @rdev: RIO device being disconnected
*
* Must be called when a user of a device is finished with it.
* When the last user of the device calls this function, the
* memory of the device is freed.
*/
void rio_dev_put(struct rio_dev *rdev)
{
if (rdev)
put_device(&rdev->dev);
}
/**
* rio_device_probe - Tell if a RIO device structure has a matching RIO
* device id structure
* @id: the RIO device id structure to match against
* @dev: the RIO device structure to match against
*
* return 0 and set rio_dev->driver when drv claims rio_dev, else error
*/
static int rio_device_probe(struct device *dev)
{
struct rio_driver *rdrv = to_rio_driver(dev->driver);
struct rio_dev *rdev = to_rio_dev(dev);
int error = -ENODEV;
const struct rio_device_id *id;
if (!rdev->driver && rdrv->probe) {
if (!rdrv->id_table)
return error;
id = rio_match_device(rdrv->id_table, rdev);
rio_dev_get(rdev);
if (id)
error = rdrv->probe(rdev, id);
if (error >= 0) {
rdev->driver = rdrv;
error = 0;
rio_dev_put(rdev);
}
}
return error;
}
/**
* rio_device_remove - Remove a RIO device from the system
*
* @dev: the RIO device structure to match against
*
* Remove a RIO device from the system. If it has an associated
* driver, then run the driver remove() method. Then update
* the reference count.
*/
static int rio_device_remove(struct device *dev)
{
struct rio_dev *rdev = to_rio_dev(dev);
struct rio_driver *rdrv = rdev->driver;
if (rdrv) {
if (rdrv->remove)
rdrv->remove(rdev);
rdev->driver = NULL;
}
rio_dev_put(rdev);
return 0;
}
/**
* rio_register_driver - register a new RIO driver
* @rdrv: the RIO driver structure to register
*
* Adds a &struct rio_driver to the list of registered drivers
* Returns a negative value on error, otherwise 0. If no error
* occurred, the driver remains registered even if no device
* was claimed during registration.
*/
int rio_register_driver(struct rio_driver *rdrv)
{
/* initialize common driver fields */
rdrv->driver.name = rdrv->name;
rdrv->driver.bus = &rio_bus_type;
/* register with core */
return driver_register(&rdrv->driver);
}
/**
* rio_unregister_driver - unregister a RIO driver
* @rdrv: the RIO driver structure to unregister
*
* Deletes the &struct rio_driver from the list of registered RIO
* drivers, gives it a chance to clean up by calling its remove()
* function for each device it was responsible for, and marks those
* devices as driverless.
*/
void rio_unregister_driver(struct rio_driver *rdrv)
{
driver_unregister(&rdrv->driver);
}
/**
* rio_match_bus - Tell if a RIO device structure has a matching RIO
* driver device id structure
* @dev: the standard device structure to match against
* @drv: the standard driver structure containing the ids to match against
*
* Used by a driver to check whether a RIO device present in the
* system is in its list of supported devices. Returns 1 if
* there is a matching &struct rio_device_id or 0 if there is
* no match.
*/
static int rio_match_bus(struct device *dev, struct device_driver *drv)
{
struct rio_dev *rdev = to_rio_dev(dev);
struct rio_driver *rdrv = to_rio_driver(drv);
const struct rio_device_id *id = rdrv->id_table;
const struct rio_device_id *found_id;
if (!id)
goto out;
found_id = rio_match_device(id, rdev);
if (found_id)
return 1;
out:return 0;
}
static struct device rio_bus = {
.bus_id = "rapidio",
};
struct bus_type rio_bus_type = {
.name = "rapidio",
.match = rio_match_bus,
.dev_attrs = rio_dev_attrs,
.probe = rio_device_probe,
.remove = rio_device_remove,
};
/**
* rio_bus_init - Register the RapidIO bus with the device model
*
* Registers the RIO bus device and RIO bus type with the Linux
* device model.
*/
static int __init rio_bus_init(void)
{
if (device_register(&rio_bus) < 0)
printk("RIO: failed to register RIO bus device\n");
return bus_register(&rio_bus_type);
}
postcore_initcall(rio_bus_init);
EXPORT_SYMBOL_GPL(rio_register_driver);
EXPORT_SYMBOL_GPL(rio_unregister_driver);
EXPORT_SYMBOL_GPL(rio_bus_type);
EXPORT_SYMBOL_GPL(rio_dev_get);
EXPORT_SYMBOL_GPL(rio_dev_put);