1 /* 2 * RapidIO driver support 3 * 4 * Copyright 2005 MontaVista Software, Inc. 5 * Matt Porter <mporter@kernel.crashing.org> 6 * 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. 11 */ 12 13 #include <linux/init.h> 14 #include <linux/module.h> 15 #include <linux/rio.h> 16 #include <linux/rio_ids.h> 17 18 #include "rio.h" 19 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 24 * 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. 28 */ 29 static const struct rio_device_id *rio_match_device(const struct rio_device_id 30 *id, 31 const struct rio_dev *rdev) 32 { 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++; 42 } 43 return NULL; 44 } 45 46 /** 47 * rio_dev_get - Increments the reference count of the RIO device structure 48 * 49 * @rdev: RIO device being referenced 50 * 51 * Each live reference to a device should be refcounted. 52 * 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. 56 */ 57 struct rio_dev *rio_dev_get(struct rio_dev *rdev) 58 { 59 if (rdev) 60 get_device(&rdev->dev); 61 62 return rdev; 63 } 64 65 /** 66 * rio_dev_put - Release a use of the RIO device structure 67 * 68 * @rdev: RIO device being disconnected 69 * 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. 73 */ 74 void rio_dev_put(struct rio_dev *rdev) 75 { 76 if (rdev) 77 put_device(&rdev->dev); 78 } 79 80 /** 81 * rio_device_probe - Tell if a RIO device structure has a matching RIO 82 * device id structure 83 * @id: the RIO device id structure to match against 84 * @dev: the RIO device structure to match against 85 * 86 * return 0 and set rio_dev->driver when drv claims rio_dev, else error 87 */ 88 static int rio_device_probe(struct device *dev) 89 { 90 struct rio_driver *rdrv = to_rio_driver(dev->driver); 91 struct rio_dev *rdev = to_rio_dev(dev); 92 int error = -ENODEV; 93 const struct rio_device_id *id; 94 95 if (!rdev->driver && rdrv->probe) { 96 if (!rdrv->id_table) 97 return error; 98 id = rio_match_device(rdrv->id_table, rdev); 99 rio_dev_get(rdev); 100 if (id) 101 error = rdrv->probe(rdev, id); 102 if (error >= 0) { 103 rdev->driver = rdrv; 104 error = 0; 105 rio_dev_put(rdev); 106 } 107 } 108 return error; 109 } 110 111 /** 112 * rio_device_remove - Remove a RIO device from the system 113 * 114 * @dev: the RIO device structure to match against 115 * 116 * Remove a RIO device from the system. If it has an associated 117 * driver, then run the driver remove() method. Then update 118 * the reference count. 119 */ 120 static int rio_device_remove(struct device *dev) 121 { 122 struct rio_dev *rdev = to_rio_dev(dev); 123 struct rio_driver *rdrv = rdev->driver; 124 125 if (rdrv) { 126 if (rdrv->remove) 127 rdrv->remove(rdev); 128 rdev->driver = NULL; 129 } 130 131 rio_dev_put(rdev); 132 133 return 0; 134 } 135 136 /** 137 * rio_register_driver - register a new RIO driver 138 * @rdrv: the RIO driver structure to register 139 * 140 * Adds a &struct rio_driver to the list of registered drivers 141 * Returns a negative value on error, otherwise 0. If no error 142 * occurred, the driver remains registered even if no device 143 * was claimed during registration. 144 */ 145 int rio_register_driver(struct rio_driver *rdrv) 146 { 147 /* initialize common driver fields */ 148 rdrv->driver.name = rdrv->name; 149 rdrv->driver.bus = &rio_bus_type; 150 rdrv->driver.probe = rio_device_probe; 151 rdrv->driver.remove = rio_device_remove; 152 153 /* register with core */ 154 return driver_register(&rdrv->driver); 155 } 156 157 /** 158 * rio_unregister_driver - unregister a RIO driver 159 * @rdrv: the RIO driver structure to unregister 160 * 161 * Deletes the &struct rio_driver from the list of registered RIO 162 * drivers, gives it a chance to clean up by calling its remove() 163 * function for each device it was responsible for, and marks those 164 * devices as driverless. 165 */ 166 void rio_unregister_driver(struct rio_driver *rdrv) 167 { 168 driver_unregister(&rdrv->driver); 169 } 170 171 /** 172 * rio_match_bus - Tell if a RIO device structure has a matching RIO 173 * driver device id structure 174 * @dev: the standard device structure to match against 175 * @drv: the standard driver structure containing the ids to match against 176 * 177 * Used by a driver to check whether a RIO device present in the 178 * system is in its list of supported devices. Returns 1 if 179 * there is a matching &struct rio_device_id or 0 if there is 180 * no match. 181 */ 182 static int rio_match_bus(struct device *dev, struct device_driver *drv) 183 { 184 struct rio_dev *rdev = to_rio_dev(dev); 185 struct rio_driver *rdrv = to_rio_driver(drv); 186 const struct rio_device_id *id = rdrv->id_table; 187 const struct rio_device_id *found_id; 188 189 if (!id) 190 goto out; 191 192 found_id = rio_match_device(id, rdev); 193 194 if (found_id) 195 return 1; 196 197 out:return 0; 198 } 199 200 static struct device rio_bus = { 201 .bus_id = "rapidio", 202 }; 203 204 struct bus_type rio_bus_type = { 205 .name = "rapidio", 206 .match = rio_match_bus, 207 .dev_attrs = rio_dev_attrs 208 }; 209 210 /** 211 * rio_bus_init - Register the RapidIO bus with the device model 212 * 213 * Registers the RIO bus device and RIO bus type with the Linux 214 * device model. 215 */ 216 static int __init rio_bus_init(void) 217 { 218 if (device_register(&rio_bus) < 0) 219 printk("RIO: failed to register RIO bus device\n"); 220 return bus_register(&rio_bus_type); 221 } 222 223 postcore_initcall(rio_bus_init); 224 225 EXPORT_SYMBOL_GPL(rio_register_driver); 226 EXPORT_SYMBOL_GPL(rio_unregister_driver); 227 EXPORT_SYMBOL_GPL(rio_bus_type); 228 EXPORT_SYMBOL_GPL(rio_dev_get); 229 EXPORT_SYMBOL_GPL(rio_dev_put); 230