Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target...
[linux-btrfs-devel.git] / drivers / rapidio / rio-driver.c
blob0f4a53bdaa3cf9b8e60c4c8dfbf5d6f80b3cf882
1 /*
2 * RapidIO driver support
4 * Copyright 2005 MontaVista Software, Inc.
5 * Matt Porter <mporter@kernel.crashing.org>
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/rio.h>
16 #include <linux/rio_ids.h>
18 #include "rio.h"
20 /**
21 * rio_match_device - Tell if a RIO device has a matching RIO device id structure
22 * @id: the RIO device id structure to match against
23 * @rdev: the RIO device structure to match against
25 * Used from driver probe and bus matching to check whether a RIO device
26 * matches a device id structure provided by a RIO driver. Returns the
27 * matching &struct rio_device_id or %NULL if there is no match.
29 static const struct rio_device_id *rio_match_device(const struct rio_device_id
30 *id,
31 const struct rio_dev *rdev)
33 while (id->vid || id->asm_vid) {
34 if (((id->vid == RIO_ANY_ID) || (id->vid == rdev->vid)) &&
35 ((id->did == RIO_ANY_ID) || (id->did == rdev->did)) &&
36 ((id->asm_vid == RIO_ANY_ID)
37 || (id->asm_vid == rdev->asm_vid))
38 && ((id->asm_did == RIO_ANY_ID)
39 || (id->asm_did == rdev->asm_did)))
40 return id;
41 id++;
43 return NULL;
46 /**
47 * rio_dev_get - Increments the reference count of the RIO device structure
49 * @rdev: RIO device being referenced
51 * Each live reference to a device should be refcounted.
53 * Drivers for RIO devices should normally record such references in
54 * their probe() methods, when they bind to a device, and release
55 * them by calling rio_dev_put(), in their disconnect() methods.
57 struct rio_dev *rio_dev_get(struct rio_dev *rdev)
59 if (rdev)
60 get_device(&rdev->dev);
62 return rdev;
65 /**
66 * rio_dev_put - Release a use of the RIO device structure
68 * @rdev: RIO device being disconnected
70 * Must be called when a user of a device is finished with it.
71 * When the last user of the device calls this function, the
72 * memory of the device is freed.
74 void rio_dev_put(struct rio_dev *rdev)
76 if (rdev)
77 put_device(&rdev->dev);
80 /**
81 * rio_device_probe - Tell if a RIO device structure has a matching RIO device id structure
82 * @dev: the RIO device structure to match against
84 * return 0 and set rio_dev->driver when drv claims rio_dev, else error
86 static int rio_device_probe(struct device *dev)
88 struct rio_driver *rdrv = to_rio_driver(dev->driver);
89 struct rio_dev *rdev = to_rio_dev(dev);
90 int error = -ENODEV;
91 const struct rio_device_id *id;
93 if (!rdev->driver && rdrv->probe) {
94 if (!rdrv->id_table)
95 return error;
96 id = rio_match_device(rdrv->id_table, rdev);
97 rio_dev_get(rdev);
98 if (id)
99 error = rdrv->probe(rdev, id);
100 if (error >= 0) {
101 rdev->driver = rdrv;
102 error = 0;
103 } else
104 rio_dev_put(rdev);
106 return error;
110 * rio_device_remove - Remove a RIO device from the system
112 * @dev: the RIO device structure to match against
114 * Remove a RIO device from the system. If it has an associated
115 * driver, then run the driver remove() method. Then update
116 * the reference count.
118 static int rio_device_remove(struct device *dev)
120 struct rio_dev *rdev = to_rio_dev(dev);
121 struct rio_driver *rdrv = rdev->driver;
123 if (rdrv) {
124 if (rdrv->remove)
125 rdrv->remove(rdev);
126 rdev->driver = NULL;
129 rio_dev_put(rdev);
131 return 0;
135 * rio_register_driver - register a new RIO driver
136 * @rdrv: the RIO driver structure to register
138 * Adds a &struct rio_driver to the list of registered drivers.
139 * Returns a negative value on error, otherwise 0. If no error
140 * occurred, the driver remains registered even if no device
141 * was claimed during registration.
143 int rio_register_driver(struct rio_driver *rdrv)
145 /* initialize common driver fields */
146 rdrv->driver.name = rdrv->name;
147 rdrv->driver.bus = &rio_bus_type;
149 /* register with core */
150 return driver_register(&rdrv->driver);
154 * rio_unregister_driver - unregister a RIO driver
155 * @rdrv: the RIO driver structure to unregister
157 * Deletes the &struct rio_driver from the list of registered RIO
158 * drivers, gives it a chance to clean up by calling its remove()
159 * function for each device it was responsible for, and marks those
160 * devices as driverless.
162 void rio_unregister_driver(struct rio_driver *rdrv)
164 driver_unregister(&rdrv->driver);
168 * rio_match_bus - Tell if a RIO device structure has a matching RIO driver device id structure
169 * @dev: the standard device structure to match against
170 * @drv: the standard driver structure containing the ids to match against
172 * Used by a driver to check whether a RIO device present in the
173 * system is in its list of supported devices. Returns 1 if
174 * there is a matching &struct rio_device_id or 0 if there is
175 * no match.
177 static int rio_match_bus(struct device *dev, struct device_driver *drv)
179 struct rio_dev *rdev = to_rio_dev(dev);
180 struct rio_driver *rdrv = to_rio_driver(drv);
181 const struct rio_device_id *id = rdrv->id_table;
182 const struct rio_device_id *found_id;
184 if (!id)
185 goto out;
187 found_id = rio_match_device(id, rdev);
189 if (found_id)
190 return 1;
192 out:return 0;
195 struct device rio_bus = {
196 .init_name = "rapidio",
199 struct bus_type rio_bus_type = {
200 .name = "rapidio",
201 .match = rio_match_bus,
202 .dev_attrs = rio_dev_attrs,
203 .probe = rio_device_probe,
204 .remove = rio_device_remove,
208 * rio_bus_init - Register the RapidIO bus with the device model
210 * Registers the RIO bus device and RIO bus type with the Linux
211 * device model.
213 static int __init rio_bus_init(void)
215 if (device_register(&rio_bus) < 0)
216 printk("RIO: failed to register RIO bus device\n");
217 return bus_register(&rio_bus_type);
220 postcore_initcall(rio_bus_init);
222 EXPORT_SYMBOL_GPL(rio_register_driver);
223 EXPORT_SYMBOL_GPL(rio_unregister_driver);
224 EXPORT_SYMBOL_GPL(rio_bus_type);
225 EXPORT_SYMBOL_GPL(rio_dev_get);
226 EXPORT_SYMBOL_GPL(rio_dev_put);