1/*
2 *  DIO Driver Services
3 *
4 *  Copyright (C) 2004 Jochen Friedrich
5 *
6 *  Loosely based on drivers/pci/pci-driver.c and drivers/zorro/zorro-driver.c
7 *
8 *  This file is subject to the terms and conditions of the GNU General Public
9 *  License.  See the file COPYING in the main directory of this archive
10 *  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 structure
20 *  @ids: array of DIO device id structures to search in
21 *  @d: the DIO device structure to match against
22 *
23 *  Used by a driver to check whether a DIO device present in the
24 *  system is in its list of supported devices. Returns the matching
25 *  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 driver
70 *  @drv: the driver structure to register
71 *
72 *  Adds the driver structure to the list of registered drivers
73 *  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 driver
89 *  @drv: the driver structure to unregister
90 *
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 for
93 *  each device it was responsible for, and marks those devices as
94 *  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 structure
105 *  @dev: the DIO device structure to match against
106 *  @drv: the &device_driver that points to the array of DIO device id structures to search
107 *
108 *  Used by the driver core to check whether a DIO device present in the
109 *  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, struct device_driver *drv)
114{
115	struct dio_dev *d = to_dio_dev(dev);
116	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