tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
20 * DIO device id structure
21 * @ids: array of DIO device id structures to search in
22 * @dev: the DIO device structure to match against
23 *
24 * Used by a driver to check whether a DIO device present in the
25 * system is in its list of supported devices. Returns the matching
26 * dio_device_id structure or %NULL if there is no match.
27 */
28
29const struct dio_device_id *
30dio_match_device(const struct dio_device_id *ids,
31 const struct dio_dev *d)
32{
33 while (ids->id) {
34 if (ids->id == DIO_WILDCARD)
35 return ids;
36 if (DIO_NEEDSSECID(ids->id & 0xff)) {
37 if (ids->id == d->id)
38 return ids;
39 } else {
40 if ((ids->id & 0xff) == (d->id & 0xff))
41 return ids;
42 }
43 ids++;
44 }
45 return NULL;
46}
47
48static int dio_device_probe(struct device *dev)
49{
50 int error = 0;
51 struct dio_driver *drv = to_dio_driver(dev->driver);
52 struct dio_dev *d = to_dio_dev(dev);
53
54 if (!d->driver && drv->probe) {
55 const struct dio_device_id *id;
56
57 id = dio_match_device(drv->id_table, d);
58 if (id)
59 error = drv->probe(d, id);
60 if (error >= 0) {
61 d->driver = drv;
62 error = 0;
63 }
64 }
65 return error;
66}
67
68
69 /**
70 * dio_register_driver - register a new DIO driver
71 * @drv: the driver structure to register
72 *
73 * Adds the driver structure to the list of registered drivers
74 * Returns the number of DIO devices which were claimed by the driver
75 * during registration. The driver remains registered even if the
76 * return value is zero.
77 */
78
79int dio_register_driver(struct dio_driver *drv)
80{
81 int count = 0;
82
83 /* initialize common driver fields */
84 drv->driver.name = drv->name;
85 drv->driver.bus = &dio_bus_type;
86 drv->driver.probe = dio_device_probe;
87
88 /* register with core */
89 count = driver_register(&drv->driver);
90 return count ? count : 1;
91}
92
93
94 /**
95 * dio_unregister_driver - unregister a DIO driver
96 * @drv: the driver structure to unregister
97 *
98 * Deletes the driver structure from the list of registered DIO drivers,
99 * gives it a chance to clean up by calling its remove() function for
100 * each device it was responsible for, and marks those devices as
101 * driverless.
102 */
103
104void dio_unregister_driver(struct dio_driver *drv)
105{
106 driver_unregister(&drv->driver);
107}
108
109
110 /**
111 * dio_bus_match - Tell if a DIO device structure has a matching DIO
112 * device id structure
113 * @ids: array of DIO device id structures to search in
114 * @dev: the DIO device structure to match against
115 *
116 * Used by a driver to check whether a DIO device present in the
117 * system is in its list of supported devices. Returns the matching
118 * dio_device_id structure or %NULL if there is no match.
119 */
120
121static int dio_bus_match(struct device *dev, struct device_driver *drv)
122{
123 struct dio_dev *d = to_dio_dev(dev);
124 struct dio_driver *dio_drv = to_dio_driver(drv);
125 const struct dio_device_id *ids = dio_drv->id_table;
126
127 if (!ids)
128 return 0;
129
130 while (ids->id) {
131 if (ids->id == DIO_WILDCARD)
132 return 1;
133 if (DIO_NEEDSSECID(ids->id & 0xff)) {
134 if (ids->id == d->id)
135 return 1;
136 } else {
137 if ((ids->id & 0xff) == (d->id & 0xff))
138 return 1;
139 }
140 ids++;
141 }
142 return 0;
143}
144
145
146struct bus_type dio_bus_type = {
147 .name = "dio",
148 .match = dio_bus_match
149};
150
151
152static int __init dio_driver_init(void)
153{
154 return bus_register(&dio_bus_type);
155}
156
157postcore_initcall(dio_driver_init);
158
159EXPORT_SYMBOL(dio_match_device);
160EXPORT_SYMBOL(dio_register_driver);
161EXPORT_SYMBOL(dio_unregister_driver);
162EXPORT_SYMBOL(dio_dev_driver);
163EXPORT_SYMBOL(dio_bus_type);