Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Functions to handle I2O drivers (OSMs) and I2O bus type for sysfs |
| 3 | * |
| 4 | * Copyright (C) 2004 Markus Lidel <Markus.Lidel@shadowconnect.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License as published by the |
| 8 | * Free Software Foundation; either version 2 of the License, or (at your |
| 9 | * option) any later version. |
| 10 | * |
| 11 | * Fixes/additions: |
| 12 | * Markus Lidel <Markus.Lidel@shadowconnect.com> |
| 13 | * initial version. |
| 14 | */ |
| 15 | |
| 16 | #include <linux/device.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/rwsem.h> |
| 19 | #include <linux/i2o.h> |
| 20 | |
| 21 | /* max_drivers - Maximum I2O drivers (OSMs) which could be registered */ |
| 22 | unsigned int i2o_max_drivers = I2O_MAX_DRIVERS; |
| 23 | module_param_named(max_drivers, i2o_max_drivers, uint, 0); |
| 24 | MODULE_PARM_DESC(max_drivers, "maximum number of OSM's to support"); |
| 25 | |
| 26 | /* I2O drivers lock and array */ |
| 27 | static spinlock_t i2o_drivers_lock; |
| 28 | static struct i2o_driver **i2o_drivers; |
| 29 | |
| 30 | /** |
| 31 | * i2o_bus_match - Tell if a I2O device class id match the class ids of |
| 32 | * the I2O driver (OSM) |
| 33 | * |
| 34 | * @dev: device which should be verified |
| 35 | * @drv: the driver to match against |
| 36 | * |
| 37 | * Used by the bus to check if the driver wants to handle the device. |
| 38 | * |
| 39 | * Returns 1 if the class ids of the driver match the class id of the |
| 40 | * device, otherwise 0. |
| 41 | */ |
| 42 | static int i2o_bus_match(struct device *dev, struct device_driver *drv) |
| 43 | { |
| 44 | struct i2o_device *i2o_dev = to_i2o_device(dev); |
| 45 | struct i2o_driver *i2o_drv = to_i2o_driver(drv); |
| 46 | struct i2o_class_id *ids = i2o_drv->classes; |
| 47 | |
| 48 | if (ids) |
| 49 | while (ids->class_id != I2O_CLASS_END) { |
| 50 | if (ids->class_id == i2o_dev->lct_data.class_id) |
| 51 | return 1; |
| 52 | ids++; |
| 53 | } |
| 54 | return 0; |
| 55 | }; |
| 56 | |
| 57 | /* I2O bus type */ |
| 58 | struct bus_type i2o_bus_type = { |
| 59 | .name = "i2o", |
| 60 | .match = i2o_bus_match, |
| 61 | }; |
| 62 | |
| 63 | /** |
| 64 | * i2o_driver_register - Register a I2O driver (OSM) in the I2O core |
| 65 | * @drv: I2O driver which should be registered |
| 66 | * |
| 67 | * Registers the OSM drv in the I2O core and creates an event queues if |
| 68 | * necessary. |
| 69 | * |
| 70 | * Returns 0 on success or negative error code on failure. |
| 71 | */ |
| 72 | int i2o_driver_register(struct i2o_driver *drv) |
| 73 | { |
| 74 | struct i2o_controller *c; |
| 75 | int i; |
| 76 | int rc = 0; |
| 77 | unsigned long flags; |
| 78 | |
| 79 | pr_debug("i2o: Register driver %s\n", drv->name); |
| 80 | |
| 81 | if (drv->event) { |
| 82 | drv->event_queue = create_workqueue(drv->name); |
| 83 | if (!drv->event_queue) { |
| 84 | printk(KERN_ERR "i2o: Could not initialize event queue " |
| 85 | "for driver %s\n", drv->name); |
| 86 | return -EFAULT; |
| 87 | } |
| 88 | pr_debug("i2o: Event queue initialized for driver %s\n", |
| 89 | drv->name); |
| 90 | } else |
| 91 | drv->event_queue = NULL; |
| 92 | |
| 93 | drv->driver.name = drv->name; |
| 94 | drv->driver.bus = &i2o_bus_type; |
| 95 | |
| 96 | spin_lock_irqsave(&i2o_drivers_lock, flags); |
| 97 | |
| 98 | for (i = 0; i2o_drivers[i]; i++) |
| 99 | if (i >= i2o_max_drivers) { |
| 100 | printk(KERN_ERR "i2o: too many drivers registered, " |
| 101 | "increase max_drivers\n"); |
| 102 | spin_unlock_irqrestore(&i2o_drivers_lock, flags); |
| 103 | return -EFAULT; |
| 104 | } |
| 105 | |
| 106 | drv->context = i; |
| 107 | i2o_drivers[i] = drv; |
| 108 | |
| 109 | spin_unlock_irqrestore(&i2o_drivers_lock, flags); |
| 110 | |
| 111 | pr_debug("i2o: driver %s gets context id %d\n", drv->name, |
| 112 | drv->context); |
| 113 | |
| 114 | list_for_each_entry(c, &i2o_controllers, list) { |
| 115 | struct i2o_device *i2o_dev; |
| 116 | |
| 117 | i2o_driver_notify_controller_add(drv, c); |
| 118 | list_for_each_entry(i2o_dev, &c->devices, list) |
| 119 | i2o_driver_notify_device_add(drv, i2o_dev); |
| 120 | } |
| 121 | |
| 122 | |
| 123 | rc = driver_register(&drv->driver); |
| 124 | if (rc) |
| 125 | destroy_workqueue(drv->event_queue); |
| 126 | |
| 127 | return rc; |
| 128 | }; |
| 129 | |
| 130 | /** |
| 131 | * i2o_driver_unregister - Unregister a I2O driver (OSM) from the I2O core |
| 132 | * @drv: I2O driver which should be unregistered |
| 133 | * |
| 134 | * Unregisters the OSM drv from the I2O core and cleanup event queues if |
| 135 | * necessary. |
| 136 | */ |
| 137 | void i2o_driver_unregister(struct i2o_driver *drv) |
| 138 | { |
| 139 | struct i2o_controller *c; |
| 140 | unsigned long flags; |
| 141 | |
| 142 | pr_debug("i2o: unregister driver %s\n", drv->name); |
| 143 | |
| 144 | driver_unregister(&drv->driver); |
| 145 | |
| 146 | list_for_each_entry(c, &i2o_controllers, list) { |
| 147 | struct i2o_device *i2o_dev; |
| 148 | |
| 149 | list_for_each_entry(i2o_dev, &c->devices, list) |
| 150 | i2o_driver_notify_device_remove(drv, i2o_dev); |
| 151 | |
| 152 | i2o_driver_notify_controller_remove(drv, c); |
| 153 | } |
| 154 | |
| 155 | spin_lock_irqsave(&i2o_drivers_lock, flags); |
| 156 | i2o_drivers[drv->context] = NULL; |
| 157 | spin_unlock_irqrestore(&i2o_drivers_lock, flags); |
| 158 | |
| 159 | if (drv->event_queue) { |
| 160 | destroy_workqueue(drv->event_queue); |
| 161 | drv->event_queue = NULL; |
| 162 | pr_debug("i2o: event queue removed for %s\n", drv->name); |
| 163 | } |
| 164 | }; |
| 165 | |
| 166 | /** |
| 167 | * i2o_driver_dispatch - dispatch an I2O reply message |
| 168 | * @c: I2O controller of the message |
| 169 | * @m: I2O message number |
| 170 | * @msg: I2O message to be delivered |
| 171 | * |
| 172 | * The reply is delivered to the driver from which the original message |
| 173 | * was. This function is only called from interrupt context. |
| 174 | * |
| 175 | * Returns 0 on success and the message should not be flushed. Returns > 0 |
| 176 | * on success and if the message should be flushed afterwords. Returns |
| 177 | * negative error code on failure (the message will be flushed too). |
| 178 | */ |
| 179 | int i2o_driver_dispatch(struct i2o_controller *c, u32 m, |
| 180 | struct i2o_message __iomem *msg) |
| 181 | { |
| 182 | struct i2o_driver *drv; |
| 183 | u32 context = readl(&msg->u.s.icntxt); |
| 184 | |
| 185 | if (likely(context < i2o_max_drivers)) { |
| 186 | spin_lock(&i2o_drivers_lock); |
| 187 | drv = i2o_drivers[context]; |
| 188 | spin_unlock(&i2o_drivers_lock); |
| 189 | |
| 190 | if (unlikely(!drv)) { |
| 191 | printk(KERN_WARNING "%s: Spurious reply to unknown " |
| 192 | "driver %d\n", c->name, context); |
| 193 | return -EIO; |
| 194 | } |
| 195 | |
| 196 | if ((readl(&msg->u.head[1]) >> 24) == I2O_CMD_UTIL_EVT_REGISTER) { |
| 197 | struct i2o_device *dev, *tmp; |
| 198 | struct i2o_event *evt; |
| 199 | u16 size; |
| 200 | u16 tid; |
| 201 | |
| 202 | tid = readl(&msg->u.head[1]) & 0x1fff; |
| 203 | |
| 204 | pr_debug("%s: event received from device %d\n", c->name, |
| 205 | tid); |
| 206 | |
| 207 | /* cut of header from message size (in 32-bit words) */ |
| 208 | size = (readl(&msg->u.head[0]) >> 16) - 5; |
| 209 | |
| 210 | evt = kmalloc(size * 4 + sizeof(*evt), GFP_ATOMIC); |
| 211 | if (!evt) |
| 212 | return -ENOMEM; |
| 213 | memset(evt, 0, size * 4 + sizeof(*evt)); |
| 214 | |
| 215 | evt->size = size; |
| 216 | memcpy_fromio(&evt->tcntxt, &msg->u.s.tcntxt, |
| 217 | (size + 2) * 4); |
| 218 | |
| 219 | list_for_each_entry_safe(dev, tmp, &c->devices, list) |
| 220 | if (dev->lct_data.tid == tid) { |
| 221 | evt->i2o_dev = dev; |
| 222 | break; |
| 223 | } |
| 224 | |
| 225 | INIT_WORK(&evt->work, (void (*)(void *))drv->event, |
| 226 | evt); |
| 227 | queue_work(drv->event_queue, &evt->work); |
| 228 | return 1; |
| 229 | } |
| 230 | |
| 231 | if (likely(drv->reply)) |
| 232 | return drv->reply(c, m, msg); |
| 233 | else |
| 234 | pr_debug("%s: Reply to driver %s, but no reply function" |
| 235 | " defined!\n", c->name, drv->name); |
| 236 | return -EIO; |
| 237 | } else |
| 238 | printk(KERN_WARNING "%s: Spurious reply to unknown driver " |
| 239 | "%d\n", c->name, readl(&msg->u.s.icntxt)); |
| 240 | return -EIO; |
| 241 | } |
| 242 | |
| 243 | /** |
| 244 | * i2o_driver_notify_controller_add_all - Send notify of added controller |
| 245 | * to all I2O drivers |
| 246 | * |
| 247 | * Send notifications to all registered drivers that a new controller was |
| 248 | * added. |
| 249 | */ |
| 250 | void i2o_driver_notify_controller_add_all(struct i2o_controller *c) |
| 251 | { |
| 252 | int i; |
| 253 | struct i2o_driver *drv; |
| 254 | |
| 255 | for (i = 0; i < I2O_MAX_DRIVERS; i++) { |
| 256 | drv = i2o_drivers[i]; |
| 257 | |
| 258 | if (drv) |
| 259 | i2o_driver_notify_controller_add(drv, c); |
| 260 | } |
| 261 | } |
| 262 | |
| 263 | /** |
| 264 | * i2o_driver_notify_controller_remove_all - Send notify of removed |
| 265 | * controller to all I2O drivers |
| 266 | * |
| 267 | * Send notifications to all registered drivers that a controller was |
| 268 | * removed. |
| 269 | */ |
| 270 | void i2o_driver_notify_controller_remove_all(struct i2o_controller *c) |
| 271 | { |
| 272 | int i; |
| 273 | struct i2o_driver *drv; |
| 274 | |
| 275 | for (i = 0; i < I2O_MAX_DRIVERS; i++) { |
| 276 | drv = i2o_drivers[i]; |
| 277 | |
| 278 | if (drv) |
| 279 | i2o_driver_notify_controller_remove(drv, c); |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | /** |
| 284 | * i2o_driver_notify_device_add_all - Send notify of added device to all |
| 285 | * I2O drivers |
| 286 | * |
| 287 | * Send notifications to all registered drivers that a device was added. |
| 288 | */ |
| 289 | void i2o_driver_notify_device_add_all(struct i2o_device *i2o_dev) |
| 290 | { |
| 291 | int i; |
| 292 | struct i2o_driver *drv; |
| 293 | |
| 294 | for (i = 0; i < I2O_MAX_DRIVERS; i++) { |
| 295 | drv = i2o_drivers[i]; |
| 296 | |
| 297 | if (drv) |
| 298 | i2o_driver_notify_device_add(drv, i2o_dev); |
| 299 | } |
| 300 | } |
| 301 | |
| 302 | /** |
| 303 | * i2o_driver_notify_device_remove_all - Send notify of removed device to |
| 304 | * all I2O drivers |
| 305 | * |
| 306 | * Send notifications to all registered drivers that a device was removed. |
| 307 | */ |
| 308 | void i2o_driver_notify_device_remove_all(struct i2o_device *i2o_dev) |
| 309 | { |
| 310 | int i; |
| 311 | struct i2o_driver *drv; |
| 312 | |
| 313 | for (i = 0; i < I2O_MAX_DRIVERS; i++) { |
| 314 | drv = i2o_drivers[i]; |
| 315 | |
| 316 | if (drv) |
| 317 | i2o_driver_notify_device_remove(drv, i2o_dev); |
| 318 | } |
| 319 | } |
| 320 | |
| 321 | /** |
| 322 | * i2o_driver_init - initialize I2O drivers (OSMs) |
| 323 | * |
| 324 | * Registers the I2O bus and allocate memory for the array of OSMs. |
| 325 | * |
| 326 | * Returns 0 on success or negative error code on failure. |
| 327 | */ |
| 328 | int __init i2o_driver_init(void) |
| 329 | { |
| 330 | int rc = 0; |
| 331 | |
| 332 | spin_lock_init(&i2o_drivers_lock); |
| 333 | |
| 334 | if ((i2o_max_drivers < 2) || (i2o_max_drivers > 64) || |
| 335 | ((i2o_max_drivers ^ (i2o_max_drivers - 1)) != |
| 336 | (2 * i2o_max_drivers - 1))) { |
| 337 | printk(KERN_WARNING "i2o: max_drivers set to %d, but must be " |
| 338 | ">=2 and <= 64 and a power of 2\n", i2o_max_drivers); |
| 339 | i2o_max_drivers = I2O_MAX_DRIVERS; |
| 340 | } |
| 341 | printk(KERN_INFO "i2o: max drivers = %d\n", i2o_max_drivers); |
| 342 | |
| 343 | i2o_drivers = |
| 344 | kmalloc(i2o_max_drivers * sizeof(*i2o_drivers), GFP_KERNEL); |
| 345 | if (!i2o_drivers) |
| 346 | return -ENOMEM; |
| 347 | |
| 348 | memset(i2o_drivers, 0, i2o_max_drivers * sizeof(*i2o_drivers)); |
| 349 | |
| 350 | rc = bus_register(&i2o_bus_type); |
| 351 | |
| 352 | if (rc < 0) |
| 353 | kfree(i2o_drivers); |
| 354 | |
| 355 | return rc; |
| 356 | }; |
| 357 | |
| 358 | /** |
| 359 | * i2o_driver_exit - clean up I2O drivers (OSMs) |
| 360 | * |
| 361 | * Unregisters the I2O bus and free driver array. |
| 362 | */ |
| 363 | void __exit i2o_driver_exit(void) |
| 364 | { |
| 365 | bus_unregister(&i2o_bus_type); |
| 366 | kfree(i2o_drivers); |
| 367 | }; |
| 368 | |
| 369 | EXPORT_SYMBOL(i2o_driver_register); |
| 370 | EXPORT_SYMBOL(i2o_driver_unregister); |
| 371 | EXPORT_SYMBOL(i2o_driver_notify_controller_add_all); |
| 372 | EXPORT_SYMBOL(i2o_driver_notify_controller_remove_all); |
| 373 | EXPORT_SYMBOL(i2o_driver_notify_device_add_all); |
| 374 | EXPORT_SYMBOL(i2o_driver_notify_device_remove_all); |