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1/*2 *  DIO Driver Services3 *4 *  Copyright (C) 2004 Jochen Friedrich5 *6 *  Loosely based on drivers/pci/pci-driver.c and drivers/zorro/zorro-driver.c7 *8 *  This file is subject to the terms and conditions of the GNU General Public9 *  License.  See the file COPYING in the main directory of this archive10 *  for more details.11 */12 13#include <linux/init.h>14#include <linux/module.h>15#include <linux/dio.h>16 17 18/**19 *  dio_match_device - Tell if a DIO device structure has a matching DIO device id structure20 *  @ids: array of DIO device id structures to search in21 *  @d: the DIO device structure to match against22 *23 *  Used by a driver to check whether a DIO device present in the24 *  system is in its list of supported devices. Returns the matching25 *  dio_device_id structure or %NULL if there is no match.26 */27 28static const struct dio_device_id *29dio_match_device(const struct dio_device_id *ids,30		   const struct dio_dev *d)31{32	while (ids->id) {33		if (ids->id == DIO_WILDCARD)34			return ids;35		if (DIO_NEEDSSECID(ids->id & 0xff)) {36			if (ids->id == d->id)37				return ids;38		} else {39			if ((ids->id & 0xff) == (d->id & 0xff))40				return ids;41		}42		ids++;43	}44	return NULL;45}46 47static int dio_device_probe(struct device *dev)48{49	int error = 0;50	struct dio_driver *drv = to_dio_driver(dev->driver);51	struct dio_dev *d = to_dio_dev(dev);52 53	if (!d->driver && drv->probe) {54		const struct dio_device_id *id;55 56		id = dio_match_device(drv->id_table, d);57		if (id)58			error = drv->probe(d, id);59		if (error >= 0) {60			d->driver = drv;61			error = 0;62		}63	}64	return error;65}66 67 68/**69 *  dio_register_driver - register a new DIO driver70 *  @drv: the driver structure to register71 *72 *  Adds the driver structure to the list of registered drivers73 *  Returns zero or a negative error value.74 */75 76int dio_register_driver(struct dio_driver *drv)77{78	/* initialize common driver fields */79	drv->driver.name = drv->name;80	drv->driver.bus = &dio_bus_type;81 82	/* register with core */83	return driver_register(&drv->driver);84}85 86 87/**88 *  dio_unregister_driver - unregister a DIO driver89 *  @drv: the driver structure to unregister90 *91 *  Deletes the driver structure from the list of registered DIO drivers,92 *  gives it a chance to clean up by calling its remove() function for93 *  each device it was responsible for, and marks those devices as94 *  driverless.95 */96 97void dio_unregister_driver(struct dio_driver *drv)98{99	driver_unregister(&drv->driver);100}101 102 103/**104 *  dio_bus_match - Tell if a DIO device structure has a matching DIO device id structure105 *  @dev: the DIO device structure to match against106 *  @drv: the &device_driver that points to the array of DIO device id structures to search107 *108 *  Used by the driver core to check whether a DIO device present in the109 *  system is in a driver's list of supported devices. Returns 1 if supported,110 *  and 0 if there is no match.111 */112 113static int dio_bus_match(struct device *dev, const struct device_driver *drv)114{115	struct dio_dev *d = to_dio_dev(dev);116	const struct dio_driver *dio_drv = to_dio_driver(drv);117	const struct dio_device_id *ids = dio_drv->id_table;118 119	if (!ids)120		return 0;121 122	return dio_match_device(ids, d) ? 1 : 0;123}124 125 126const struct bus_type dio_bus_type = {127	.name	= "dio",128	.match	= dio_bus_match,129	.probe	= dio_device_probe,130};131 132 133static int __init dio_driver_init(void)134{135	return bus_register(&dio_bus_type);136}137 138postcore_initcall(dio_driver_init);139 140EXPORT_SYMBOL(dio_register_driver);141EXPORT_SYMBOL(dio_unregister_driver);142EXPORT_SYMBOL(dio_bus_type);143