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 device id structure 82 * @id: the RIO device id structure to match against 83 * @dev: the RIO device structure to match against 84 * 85 * return 0 and set rio_dev->driver when drv claims rio_dev, else error 86 */ 87 static int rio_device_probe(struct device *dev) 88 { 89 struct rio_driver *rdrv = to_rio_driver(dev->driver); 90 struct rio_dev *rdev = to_rio_dev(dev); 91 int error = -ENODEV; 92 const struct rio_device_id *id; 93 94 if (!rdev->driver && rdrv->probe) { 95 if (!rdrv->id_table) 96 return error; 97 id = rio_match_device(rdrv->id_table, rdev); 98 rio_dev_get(rdev); 99 if (id) 100 error = rdrv->probe(rdev, id); 101 if (error >= 0) { 102 rdev->driver = rdrv; 103 error = 0; 104 } else 105 rio_dev_put(rdev); 106 } 107 return error; 108 } 109 110 /** 111 * rio_device_remove - Remove a RIO device from the system 112 * 113 * @dev: the RIO device structure to match against 114 * 115 * Remove a RIO device from the system. If it has an associated 116 * driver, then run the driver remove() method. Then update 117 * the reference count. 118 */ 119 static int rio_device_remove(struct device *dev) 120 { 121 struct rio_dev *rdev = to_rio_dev(dev); 122 struct rio_driver *rdrv = rdev->driver; 123 124 if (rdrv) { 125 if (rdrv->remove) 126 rdrv->remove(rdev); 127 rdev->driver = NULL; 128 } 129 130 rio_dev_put(rdev); 131 132 return 0; 133 } 134 135 /** 136 * rio_register_driver - register a new RIO driver 137 * @rdrv: the RIO driver structure to register 138 * 139 * Adds a &struct rio_driver to the list of registered drivers. 140 * Returns a negative value on error, otherwise 0. If no error 141 * occurred, the driver remains registered even if no device 142 * was claimed during registration. 143 */ 144 int rio_register_driver(struct rio_driver *rdrv) 145 { 146 /* initialize common driver fields */ 147 rdrv->driver.name = rdrv->name; 148 rdrv->driver.bus = &rio_bus_type; 149 150 /* register with core */ 151 return driver_register(&rdrv->driver); 152 } 153 154 /** 155 * rio_unregister_driver - unregister a RIO driver 156 * @rdrv: the RIO driver structure to unregister 157 * 158 * Deletes the &struct rio_driver from the list of registered RIO 159 * drivers, gives it a chance to clean up by calling its remove() 160 * function for each device it was responsible for, and marks those 161 * devices as driverless. 162 */ 163 void rio_unregister_driver(struct rio_driver *rdrv) 164 { 165 driver_unregister(&rdrv->driver); 166 } 167 168 /** 169 * rio_match_bus - Tell if a RIO device structure has a matching RIO driver device id structure 170 * @dev: the standard device structure to match against 171 * @drv: the standard driver structure containing the ids to match against 172 * 173 * Used by a driver to check whether a RIO device present in the 174 * system is in its list of supported devices. Returns 1 if 175 * there is a matching &struct rio_device_id or 0 if there is 176 * no match. 177 */ 178 static int rio_match_bus(struct device *dev, struct device_driver *drv) 179 { 180 struct rio_dev *rdev = to_rio_dev(dev); 181 struct rio_driver *rdrv = to_rio_driver(drv); 182 const struct rio_device_id *id = rdrv->id_table; 183 const struct rio_device_id *found_id; 184 185 if (!id) 186 goto out; 187 188 found_id = rio_match_device(id, rdev); 189 190 if (found_id) 191 return 1; 192 193 out:return 0; 194 } 195 196 static struct device rio_bus = { 197 .bus_id = "rapidio", 198 }; 199 200 struct bus_type rio_bus_type = { 201 .name = "rapidio", 202 .match = rio_match_bus, 203 .dev_attrs = rio_dev_attrs, 204 .probe = rio_device_probe, 205 .remove = rio_device_remove, 206 }; 207 208 /** 209 * rio_bus_init - Register the RapidIO bus with the device model 210 * 211 * Registers the RIO bus device and RIO bus type with the Linux 212 * device model. 213 */ 214 static int __init rio_bus_init(void) 215 { 216 if (device_register(&rio_bus) < 0) 217 printk("RIO: failed to register RIO bus device\n"); 218 return bus_register(&rio_bus_type); 219 } 220 221 postcore_initcall(rio_bus_init); 222 223 EXPORT_SYMBOL_GPL(rio_register_driver); 224 EXPORT_SYMBOL_GPL(rio_unregister_driver); 225 EXPORT_SYMBOL_GPL(rio_bus_type); 226 EXPORT_SYMBOL_GPL(rio_dev_get); 227 EXPORT_SYMBOL_GPL(rio_dev_put); 228