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
28 static const struct dio_device_id *
dio_match_device(const struct dio_device_id * ids,const struct dio_dev * d)29 dio_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
dio_device_probe(struct device * dev)47 static 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
dio_register_driver(struct dio_driver * drv)76 int 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
dio_unregister_driver(struct dio_driver * drv)97 void 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
dio_bus_match(struct device * dev,struct device_driver * drv)113 static 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
126 struct bus_type dio_bus_type = {
127 .name = "dio",
128 .match = dio_bus_match,
129 .probe = dio_device_probe,
130 };
131
132
dio_driver_init(void)133 static int __init dio_driver_init(void)
134 {
135 return bus_register(&dio_bus_type);
136 }
137
138 postcore_initcall(dio_driver_init);
139
140 EXPORT_SYMBOL(dio_register_driver);
141 EXPORT_SYMBOL(dio_unregister_driver);
142 EXPORT_SYMBOL(dio_bus_type);
143