linux/drivers/dio/dio-driver.c

143 lines
3.4 KiB
C

/*
* DIO Driver Services
*
* Copyright (C) 2004 Jochen Friedrich
*
* Loosely based on drivers/pci/pci-driver.c and drivers/zorro/zorro-driver.c
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/dio.h>
/**
* dio_match_device - Tell if a DIO device structure has a matching DIO device id structure
* @ids: array of DIO device id structures to search in
* @d: the DIO device structure to match against
*
* Used by a driver to check whether a DIO device present in the
* system is in its list of supported devices. Returns the matching
* dio_device_id structure or %NULL if there is no match.
*/
static const struct dio_device_id *
dio_match_device(const struct dio_device_id *ids,
const struct dio_dev *d)
{
while (ids->id) {
if (ids->id == DIO_WILDCARD)
return ids;
if (DIO_NEEDSSECID(ids->id & 0xff)) {
if (ids->id == d->id)
return ids;
} else {
if ((ids->id & 0xff) == (d->id & 0xff))
return ids;
}
ids++;
}
return NULL;
}
static int dio_device_probe(struct device *dev)
{
int error = 0;
struct dio_driver *drv = to_dio_driver(dev->driver);
struct dio_dev *d = to_dio_dev(dev);
if (!d->driver && drv->probe) {
const struct dio_device_id *id;
id = dio_match_device(drv->id_table, d);
if (id)
error = drv->probe(d, id);
if (error >= 0) {
d->driver = drv;
error = 0;
}
}
return error;
}
/**
* dio_register_driver - register a new DIO driver
* @drv: the driver structure to register
*
* Adds the driver structure to the list of registered drivers
* Returns zero or a negative error value.
*/
int dio_register_driver(struct dio_driver *drv)
{
/* initialize common driver fields */
drv->driver.name = drv->name;
drv->driver.bus = &dio_bus_type;
/* register with core */
return driver_register(&drv->driver);
}
/**
* dio_unregister_driver - unregister a DIO driver
* @drv: the driver structure to unregister
*
* Deletes the driver structure from the list of registered DIO 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 dio_unregister_driver(struct dio_driver *drv)
{
driver_unregister(&drv->driver);
}
/**
* dio_bus_match - Tell if a DIO device structure has a matching DIO device id structure
* @dev: the DIO device structure to match against
* @drv: the &device_driver that points to the array of DIO device id structures to search
*
* Used by the driver core to check whether a DIO device present in the
* system is in a driver's list of supported devices. Returns 1 if supported,
* and 0 if there is no match.
*/
static int dio_bus_match(struct device *dev, struct device_driver *drv)
{
struct dio_dev *d = to_dio_dev(dev);
struct dio_driver *dio_drv = to_dio_driver(drv);
const struct dio_device_id *ids = dio_drv->id_table;
if (!ids)
return 0;
return dio_match_device(ids, d) ? 1 : 0;
}
struct bus_type dio_bus_type = {
.name = "dio",
.match = dio_bus_match,
.probe = dio_device_probe,
};
static int __init dio_driver_init(void)
{
return bus_register(&dio_bus_type);
}
postcore_initcall(dio_driver_init);
EXPORT_SYMBOL(dio_register_driver);
EXPORT_SYMBOL(dio_unregister_driver);
EXPORT_SYMBOL(dio_bus_type);