1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * RapidIO driver support
4 *
5 * Copyright 2005 MontaVista Software, Inc.
6 * Matt Porter <mporter@kernel.crashing.org>
7 */
8
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/rio.h>
12 #include <linux/rio_ids.h>
13 #include <linux/rio_drv.h>
14
15 #include "rio.h"
16
17 /**
18 * rio_match_device - Tell if a RIO device has a matching RIO device id structure
19 * @id: the RIO device id structure to match against
20 * @rdev: the RIO device structure to match against
21 *
22 * Used from driver probe and bus matching to check whether a RIO device
23 * matches a device id structure provided by a RIO driver. Returns the
24 * matching &struct rio_device_id or %NULL if there is no match.
25 */
rio_match_device(const struct rio_device_id * id,const struct rio_dev * rdev)26 static const struct rio_device_id *rio_match_device(const struct rio_device_id
27 *id,
28 const struct rio_dev *rdev)
29 {
30 while (id->vid || id->asm_vid) {
31 if (((id->vid == RIO_ANY_ID) || (id->vid == rdev->vid)) &&
32 ((id->did == RIO_ANY_ID) || (id->did == rdev->did)) &&
33 ((id->asm_vid == RIO_ANY_ID)
34 || (id->asm_vid == rdev->asm_vid))
35 && ((id->asm_did == RIO_ANY_ID)
36 || (id->asm_did == rdev->asm_did)))
37 return id;
38 id++;
39 }
40 return NULL;
41 }
42
43 /**
44 * rio_dev_get - Increments the reference count of the RIO device structure
45 *
46 * @rdev: RIO device being referenced
47 *
48 * Each live reference to a device should be refcounted.
49 *
50 * Drivers for RIO devices should normally record such references in
51 * their probe() methods, when they bind to a device, and release
52 * them by calling rio_dev_put(), in their disconnect() methods.
53 */
rio_dev_get(struct rio_dev * rdev)54 struct rio_dev *rio_dev_get(struct rio_dev *rdev)
55 {
56 if (rdev)
57 get_device(&rdev->dev);
58
59 return rdev;
60 }
61
62 /**
63 * rio_dev_put - Release a use of the RIO device structure
64 *
65 * @rdev: RIO device being disconnected
66 *
67 * Must be called when a user of a device is finished with it.
68 * When the last user of the device calls this function, the
69 * memory of the device is freed.
70 */
rio_dev_put(struct rio_dev * rdev)71 void rio_dev_put(struct rio_dev *rdev)
72 {
73 if (rdev)
74 put_device(&rdev->dev);
75 }
76
77 /**
78 * rio_device_probe - Tell if a RIO device structure has a matching RIO device id structure
79 * @dev: the RIO device structure to match against
80 *
81 * return 0 and set rio_dev->driver when drv claims rio_dev, else error
82 */
rio_device_probe(struct device * dev)83 static int rio_device_probe(struct device *dev)
84 {
85 struct rio_driver *rdrv = to_rio_driver(dev->driver);
86 struct rio_dev *rdev = to_rio_dev(dev);
87 int error = -ENODEV;
88 const struct rio_device_id *id;
89
90 if (!rdev->driver && rdrv->probe) {
91 if (!rdrv->id_table)
92 return error;
93 id = rio_match_device(rdrv->id_table, rdev);
94 rio_dev_get(rdev);
95 if (id)
96 error = rdrv->probe(rdev, id);
97 if (error >= 0) {
98 rdev->driver = rdrv;
99 error = 0;
100 } else
101 rio_dev_put(rdev);
102 }
103 return error;
104 }
105
106 /**
107 * rio_device_remove - Remove a RIO device from the system
108 *
109 * @dev: the RIO device structure to match against
110 *
111 * Remove a RIO device from the system. If it has an associated
112 * driver, then run the driver remove() method. Then update
113 * the reference count.
114 */
rio_device_remove(struct device * dev)115 static void rio_device_remove(struct device *dev)
116 {
117 struct rio_dev *rdev = to_rio_dev(dev);
118 struct rio_driver *rdrv = rdev->driver;
119
120 if (rdrv) {
121 if (rdrv->remove)
122 rdrv->remove(rdev);
123 rdev->driver = NULL;
124 }
125
126 rio_dev_put(rdev);
127 }
128
rio_device_shutdown(struct device * dev)129 static void rio_device_shutdown(struct device *dev)
130 {
131 struct rio_dev *rdev = to_rio_dev(dev);
132 struct rio_driver *rdrv = rdev->driver;
133
134 dev_dbg(dev, "RIO: %s\n", __func__);
135
136 if (rdrv && rdrv->shutdown)
137 rdrv->shutdown(rdev);
138 }
139
140 /**
141 * rio_register_driver - register a new RIO driver
142 * @rdrv: the RIO driver structure to register
143 *
144 * Adds a &struct rio_driver to the list of registered drivers.
145 * Returns a negative value on error, otherwise 0. If no error
146 * occurred, the driver remains registered even if no device
147 * was claimed during registration.
148 */
rio_register_driver(struct rio_driver * rdrv)149 int rio_register_driver(struct rio_driver *rdrv)
150 {
151 /* initialize common driver fields */
152 rdrv->driver.name = rdrv->name;
153 rdrv->driver.bus = &rio_bus_type;
154
155 /* register with core */
156 return driver_register(&rdrv->driver);
157 }
158
159 /**
160 * rio_unregister_driver - unregister a RIO driver
161 * @rdrv: the RIO driver structure to unregister
162 *
163 * Deletes the &struct rio_driver from the list of registered RIO
164 * drivers, gives it a chance to clean up by calling its remove()
165 * function for each device it was responsible for, and marks those
166 * devices as driverless.
167 */
rio_unregister_driver(struct rio_driver * rdrv)168 void rio_unregister_driver(struct rio_driver *rdrv)
169 {
170 driver_unregister(&rdrv->driver);
171 }
172
rio_attach_device(struct rio_dev * rdev)173 void rio_attach_device(struct rio_dev *rdev)
174 {
175 rdev->dev.bus = &rio_bus_type;
176 }
177 EXPORT_SYMBOL_GPL(rio_attach_device);
178
179 /**
180 * rio_match_bus - Tell if a RIO device structure has a matching RIO driver device id structure
181 * @dev: the standard device structure to match against
182 * @drv: the standard driver structure containing the ids to match against
183 *
184 * Used by a driver to check whether a RIO device present in the
185 * system is in its list of supported devices. Returns 1 if
186 * there is a matching &struct rio_device_id or 0 if there is
187 * no match.
188 */
rio_match_bus(struct device * dev,struct device_driver * drv)189 static int rio_match_bus(struct device *dev, struct device_driver *drv)
190 {
191 struct rio_dev *rdev = to_rio_dev(dev);
192 struct rio_driver *rdrv = to_rio_driver(drv);
193 const struct rio_device_id *id = rdrv->id_table;
194 const struct rio_device_id *found_id;
195
196 if (!id)
197 goto out;
198
199 found_id = rio_match_device(id, rdev);
200
201 if (found_id)
202 return 1;
203
204 out:return 0;
205 }
206
rio_uevent(const struct device * dev,struct kobj_uevent_env * env)207 static int rio_uevent(const struct device *dev, struct kobj_uevent_env *env)
208 {
209 const struct rio_dev *rdev;
210
211 if (!dev)
212 return -ENODEV;
213
214 rdev = to_rio_dev(dev);
215 if (!rdev)
216 return -ENODEV;
217
218 if (add_uevent_var(env, "MODALIAS=rapidio:v%04Xd%04Xav%04Xad%04X",
219 rdev->vid, rdev->did, rdev->asm_vid, rdev->asm_did))
220 return -ENOMEM;
221 return 0;
222 }
223
224 struct class rio_mport_class = {
225 .name = "rapidio_port",
226 .dev_groups = rio_mport_groups,
227 };
228 EXPORT_SYMBOL_GPL(rio_mport_class);
229
230 struct bus_type rio_bus_type = {
231 .name = "rapidio",
232 .match = rio_match_bus,
233 .dev_groups = rio_dev_groups,
234 .bus_groups = rio_bus_groups,
235 .probe = rio_device_probe,
236 .remove = rio_device_remove,
237 .shutdown = rio_device_shutdown,
238 .uevent = rio_uevent,
239 };
240
241 /**
242 * rio_bus_init - Register the RapidIO bus with the device model
243 *
244 * Registers the RIO mport device class and RIO bus type with the Linux
245 * device model.
246 */
rio_bus_init(void)247 static int __init rio_bus_init(void)
248 {
249 int ret;
250
251 ret = class_register(&rio_mport_class);
252 if (!ret) {
253 ret = bus_register(&rio_bus_type);
254 if (ret)
255 class_unregister(&rio_mport_class);
256 }
257 return ret;
258 }
259
260 postcore_initcall(rio_bus_init);
261
262 EXPORT_SYMBOL_GPL(rio_register_driver);
263 EXPORT_SYMBOL_GPL(rio_unregister_driver);
264 EXPORT_SYMBOL_GPL(rio_bus_type);
265 EXPORT_SYMBOL_GPL(rio_dev_get);
266 EXPORT_SYMBOL_GPL(rio_dev_put);
267