1 /* 2 * Copyright (C) 2012 Avionic Design GmbH 3 * Copyright (C) 2012-2013, NVIDIA Corporation 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program. If not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #include <linux/host1x.h> 19 #include <linux/of.h> 20 #include <linux/slab.h> 21 22 #include "bus.h" 23 #include "dev.h" 24 25 static DEFINE_MUTEX(clients_lock); 26 static LIST_HEAD(clients); 27 28 static DEFINE_MUTEX(drivers_lock); 29 static LIST_HEAD(drivers); 30 31 static DEFINE_MUTEX(devices_lock); 32 static LIST_HEAD(devices); 33 34 struct host1x_subdev { 35 struct host1x_client *client; 36 struct device_node *np; 37 struct list_head list; 38 }; 39 40 /** 41 * host1x_subdev_add() - add a new subdevice with an associated device node 42 */ 43 static int host1x_subdev_add(struct host1x_device *device, 44 struct device_node *np) 45 { 46 struct host1x_subdev *subdev; 47 48 subdev = kzalloc(sizeof(*subdev), GFP_KERNEL); 49 if (!subdev) 50 return -ENOMEM; 51 52 INIT_LIST_HEAD(&subdev->list); 53 subdev->np = of_node_get(np); 54 55 mutex_lock(&device->subdevs_lock); 56 list_add_tail(&subdev->list, &device->subdevs); 57 mutex_unlock(&device->subdevs_lock); 58 59 return 0; 60 } 61 62 /** 63 * host1x_subdev_del() - remove subdevice 64 */ 65 static void host1x_subdev_del(struct host1x_subdev *subdev) 66 { 67 list_del(&subdev->list); 68 of_node_put(subdev->np); 69 kfree(subdev); 70 } 71 72 /** 73 * host1x_device_parse_dt() - scan device tree and add matching subdevices 74 */ 75 static int host1x_device_parse_dt(struct host1x_device *device, 76 struct host1x_driver *driver) 77 { 78 struct device_node *np; 79 int err; 80 81 for_each_child_of_node(device->dev.parent->of_node, np) { 82 if (of_match_node(driver->subdevs, np) && 83 of_device_is_available(np)) { 84 err = host1x_subdev_add(device, np); 85 if (err < 0) 86 return err; 87 } 88 } 89 90 return 0; 91 } 92 93 static void host1x_subdev_register(struct host1x_device *device, 94 struct host1x_subdev *subdev, 95 struct host1x_client *client) 96 { 97 int err; 98 99 /* 100 * Move the subdevice to the list of active (registered) subdevices 101 * and associate it with a client. At the same time, associate the 102 * client with its parent device. 103 */ 104 mutex_lock(&device->subdevs_lock); 105 mutex_lock(&device->clients_lock); 106 list_move_tail(&client->list, &device->clients); 107 list_move_tail(&subdev->list, &device->active); 108 client->parent = &device->dev; 109 subdev->client = client; 110 mutex_unlock(&device->clients_lock); 111 mutex_unlock(&device->subdevs_lock); 112 113 if (list_empty(&device->subdevs)) { 114 err = device_add(&device->dev); 115 if (err < 0) 116 dev_err(&device->dev, "failed to add: %d\n", err); 117 else 118 device->registered = true; 119 } 120 } 121 122 static void __host1x_subdev_unregister(struct host1x_device *device, 123 struct host1x_subdev *subdev) 124 { 125 struct host1x_client *client = subdev->client; 126 127 /* 128 * If all subdevices have been activated, we're about to remove the 129 * first active subdevice, so unload the driver first. 130 */ 131 if (list_empty(&device->subdevs)) { 132 if (device->registered) { 133 device->registered = false; 134 device_del(&device->dev); 135 } 136 } 137 138 /* 139 * Move the subdevice back to the list of idle subdevices and remove 140 * it from list of clients. 141 */ 142 mutex_lock(&device->clients_lock); 143 subdev->client = NULL; 144 client->parent = NULL; 145 list_move_tail(&subdev->list, &device->subdevs); 146 /* 147 * XXX: Perhaps don't do this here, but rather explicitly remove it 148 * when the device is about to be deleted. 149 * 150 * This is somewhat complicated by the fact that this function is 151 * used to remove the subdevice when a client is unregistered but 152 * also when the composite device is about to be removed. 153 */ 154 list_del_init(&client->list); 155 mutex_unlock(&device->clients_lock); 156 } 157 158 static void host1x_subdev_unregister(struct host1x_device *device, 159 struct host1x_subdev *subdev) 160 { 161 mutex_lock(&device->subdevs_lock); 162 __host1x_subdev_unregister(device, subdev); 163 mutex_unlock(&device->subdevs_lock); 164 } 165 166 int host1x_device_init(struct host1x_device *device) 167 { 168 struct host1x_client *client; 169 int err; 170 171 mutex_lock(&device->clients_lock); 172 173 list_for_each_entry(client, &device->clients, list) { 174 if (client->ops && client->ops->init) { 175 err = client->ops->init(client); 176 if (err < 0) { 177 dev_err(&device->dev, 178 "failed to initialize %s: %d\n", 179 dev_name(client->dev), err); 180 mutex_unlock(&device->clients_lock); 181 return err; 182 } 183 } 184 } 185 186 mutex_unlock(&device->clients_lock); 187 188 return 0; 189 } 190 EXPORT_SYMBOL(host1x_device_init); 191 192 int host1x_device_exit(struct host1x_device *device) 193 { 194 struct host1x_client *client; 195 int err; 196 197 mutex_lock(&device->clients_lock); 198 199 list_for_each_entry_reverse(client, &device->clients, list) { 200 if (client->ops && client->ops->exit) { 201 err = client->ops->exit(client); 202 if (err < 0) { 203 dev_err(&device->dev, 204 "failed to cleanup %s: %d\n", 205 dev_name(client->dev), err); 206 mutex_unlock(&device->clients_lock); 207 return err; 208 } 209 } 210 } 211 212 mutex_unlock(&device->clients_lock); 213 214 return 0; 215 } 216 EXPORT_SYMBOL(host1x_device_exit); 217 218 static int host1x_add_client(struct host1x *host1x, 219 struct host1x_client *client) 220 { 221 struct host1x_device *device; 222 struct host1x_subdev *subdev; 223 224 mutex_lock(&host1x->devices_lock); 225 226 list_for_each_entry(device, &host1x->devices, list) { 227 list_for_each_entry(subdev, &device->subdevs, list) { 228 if (subdev->np == client->dev->of_node) { 229 host1x_subdev_register(device, subdev, client); 230 mutex_unlock(&host1x->devices_lock); 231 return 0; 232 } 233 } 234 } 235 236 mutex_unlock(&host1x->devices_lock); 237 return -ENODEV; 238 } 239 240 static int host1x_del_client(struct host1x *host1x, 241 struct host1x_client *client) 242 { 243 struct host1x_device *device, *dt; 244 struct host1x_subdev *subdev; 245 246 mutex_lock(&host1x->devices_lock); 247 248 list_for_each_entry_safe(device, dt, &host1x->devices, list) { 249 list_for_each_entry(subdev, &device->active, list) { 250 if (subdev->client == client) { 251 host1x_subdev_unregister(device, subdev); 252 mutex_unlock(&host1x->devices_lock); 253 return 0; 254 } 255 } 256 } 257 258 mutex_unlock(&host1x->devices_lock); 259 return -ENODEV; 260 } 261 262 static int host1x_device_match(struct device *dev, struct device_driver *drv) 263 { 264 return strcmp(dev_name(dev), drv->name) == 0; 265 } 266 267 static int host1x_device_probe(struct device *dev) 268 { 269 struct host1x_driver *driver = to_host1x_driver(dev->driver); 270 struct host1x_device *device = to_host1x_device(dev); 271 272 if (driver->probe) 273 return driver->probe(device); 274 275 return 0; 276 } 277 278 static int host1x_device_remove(struct device *dev) 279 { 280 struct host1x_driver *driver = to_host1x_driver(dev->driver); 281 struct host1x_device *device = to_host1x_device(dev); 282 283 if (driver->remove) 284 return driver->remove(device); 285 286 return 0; 287 } 288 289 static void host1x_device_shutdown(struct device *dev) 290 { 291 struct host1x_driver *driver = to_host1x_driver(dev->driver); 292 struct host1x_device *device = to_host1x_device(dev); 293 294 if (driver->shutdown) 295 driver->shutdown(device); 296 } 297 298 static const struct dev_pm_ops host1x_device_pm_ops = { 299 .suspend = pm_generic_suspend, 300 .resume = pm_generic_resume, 301 .freeze = pm_generic_freeze, 302 .thaw = pm_generic_thaw, 303 .poweroff = pm_generic_poweroff, 304 .restore = pm_generic_restore, 305 }; 306 307 struct bus_type host1x_bus_type = { 308 .name = "host1x", 309 .match = host1x_device_match, 310 .probe = host1x_device_probe, 311 .remove = host1x_device_remove, 312 .shutdown = host1x_device_shutdown, 313 .pm = &host1x_device_pm_ops, 314 }; 315 316 static void __host1x_device_del(struct host1x_device *device) 317 { 318 struct host1x_subdev *subdev, *sd; 319 struct host1x_client *client, *cl; 320 321 mutex_lock(&device->subdevs_lock); 322 323 /* unregister subdevices */ 324 list_for_each_entry_safe(subdev, sd, &device->active, list) { 325 /* 326 * host1x_subdev_unregister() will remove the client from 327 * any lists, so we'll need to manually add it back to the 328 * list of idle clients. 329 * 330 * XXX: Alternatively, perhaps don't remove the client from 331 * any lists in host1x_subdev_unregister() and instead do 332 * that explicitly from host1x_unregister_client()? 333 */ 334 client = subdev->client; 335 336 __host1x_subdev_unregister(device, subdev); 337 338 /* add the client to the list of idle clients */ 339 mutex_lock(&clients_lock); 340 list_add_tail(&client->list, &clients); 341 mutex_unlock(&clients_lock); 342 } 343 344 /* remove subdevices */ 345 list_for_each_entry_safe(subdev, sd, &device->subdevs, list) 346 host1x_subdev_del(subdev); 347 348 mutex_unlock(&device->subdevs_lock); 349 350 /* move clients to idle list */ 351 mutex_lock(&clients_lock); 352 mutex_lock(&device->clients_lock); 353 354 list_for_each_entry_safe(client, cl, &device->clients, list) 355 list_move_tail(&client->list, &clients); 356 357 mutex_unlock(&device->clients_lock); 358 mutex_unlock(&clients_lock); 359 360 /* finally remove the device */ 361 list_del_init(&device->list); 362 } 363 364 static void host1x_device_release(struct device *dev) 365 { 366 struct host1x_device *device = to_host1x_device(dev); 367 368 __host1x_device_del(device); 369 kfree(device); 370 } 371 372 static int host1x_device_add(struct host1x *host1x, 373 struct host1x_driver *driver) 374 { 375 struct host1x_client *client, *tmp; 376 struct host1x_subdev *subdev; 377 struct host1x_device *device; 378 int err; 379 380 device = kzalloc(sizeof(*device), GFP_KERNEL); 381 if (!device) 382 return -ENOMEM; 383 384 device_initialize(&device->dev); 385 386 mutex_init(&device->subdevs_lock); 387 INIT_LIST_HEAD(&device->subdevs); 388 INIT_LIST_HEAD(&device->active); 389 mutex_init(&device->clients_lock); 390 INIT_LIST_HEAD(&device->clients); 391 INIT_LIST_HEAD(&device->list); 392 device->driver = driver; 393 394 device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask; 395 device->dev.dma_mask = &device->dev.coherent_dma_mask; 396 dev_set_name(&device->dev, "%s", driver->driver.name); 397 device->dev.release = host1x_device_release; 398 device->dev.bus = &host1x_bus_type; 399 device->dev.parent = host1x->dev; 400 401 err = host1x_device_parse_dt(device, driver); 402 if (err < 0) { 403 kfree(device); 404 return err; 405 } 406 407 list_add_tail(&device->list, &host1x->devices); 408 409 mutex_lock(&clients_lock); 410 411 list_for_each_entry_safe(client, tmp, &clients, list) { 412 list_for_each_entry(subdev, &device->subdevs, list) { 413 if (subdev->np == client->dev->of_node) { 414 host1x_subdev_register(device, subdev, client); 415 break; 416 } 417 } 418 } 419 420 mutex_unlock(&clients_lock); 421 422 return 0; 423 } 424 425 /* 426 * Removes a device by first unregistering any subdevices and then removing 427 * itself from the list of devices. 428 * 429 * This function must be called with the host1x->devices_lock held. 430 */ 431 static void host1x_device_del(struct host1x *host1x, 432 struct host1x_device *device) 433 { 434 if (device->registered) { 435 device->registered = false; 436 device_del(&device->dev); 437 } 438 439 put_device(&device->dev); 440 } 441 442 static void host1x_attach_driver(struct host1x *host1x, 443 struct host1x_driver *driver) 444 { 445 struct host1x_device *device; 446 int err; 447 448 mutex_lock(&host1x->devices_lock); 449 450 list_for_each_entry(device, &host1x->devices, list) { 451 if (device->driver == driver) { 452 mutex_unlock(&host1x->devices_lock); 453 return; 454 } 455 } 456 457 err = host1x_device_add(host1x, driver); 458 if (err < 0) 459 dev_err(host1x->dev, "failed to allocate device: %d\n", err); 460 461 mutex_unlock(&host1x->devices_lock); 462 } 463 464 static void host1x_detach_driver(struct host1x *host1x, 465 struct host1x_driver *driver) 466 { 467 struct host1x_device *device, *tmp; 468 469 mutex_lock(&host1x->devices_lock); 470 471 list_for_each_entry_safe(device, tmp, &host1x->devices, list) 472 if (device->driver == driver) 473 host1x_device_del(host1x, device); 474 475 mutex_unlock(&host1x->devices_lock); 476 } 477 478 int host1x_register(struct host1x *host1x) 479 { 480 struct host1x_driver *driver; 481 482 mutex_lock(&devices_lock); 483 list_add_tail(&host1x->list, &devices); 484 mutex_unlock(&devices_lock); 485 486 mutex_lock(&drivers_lock); 487 488 list_for_each_entry(driver, &drivers, list) 489 host1x_attach_driver(host1x, driver); 490 491 mutex_unlock(&drivers_lock); 492 493 return 0; 494 } 495 496 int host1x_unregister(struct host1x *host1x) 497 { 498 struct host1x_driver *driver; 499 500 mutex_lock(&drivers_lock); 501 502 list_for_each_entry(driver, &drivers, list) 503 host1x_detach_driver(host1x, driver); 504 505 mutex_unlock(&drivers_lock); 506 507 mutex_lock(&devices_lock); 508 list_del_init(&host1x->list); 509 mutex_unlock(&devices_lock); 510 511 return 0; 512 } 513 514 int host1x_driver_register_full(struct host1x_driver *driver, 515 struct module *owner) 516 { 517 struct host1x *host1x; 518 519 INIT_LIST_HEAD(&driver->list); 520 521 mutex_lock(&drivers_lock); 522 list_add_tail(&driver->list, &drivers); 523 mutex_unlock(&drivers_lock); 524 525 mutex_lock(&devices_lock); 526 527 list_for_each_entry(host1x, &devices, list) 528 host1x_attach_driver(host1x, driver); 529 530 mutex_unlock(&devices_lock); 531 532 driver->driver.bus = &host1x_bus_type; 533 driver->driver.owner = owner; 534 535 return driver_register(&driver->driver); 536 } 537 EXPORT_SYMBOL(host1x_driver_register_full); 538 539 void host1x_driver_unregister(struct host1x_driver *driver) 540 { 541 driver_unregister(&driver->driver); 542 543 mutex_lock(&drivers_lock); 544 list_del_init(&driver->list); 545 mutex_unlock(&drivers_lock); 546 } 547 EXPORT_SYMBOL(host1x_driver_unregister); 548 549 int host1x_client_register(struct host1x_client *client) 550 { 551 struct host1x *host1x; 552 int err; 553 554 mutex_lock(&devices_lock); 555 556 list_for_each_entry(host1x, &devices, list) { 557 err = host1x_add_client(host1x, client); 558 if (!err) { 559 mutex_unlock(&devices_lock); 560 return 0; 561 } 562 } 563 564 mutex_unlock(&devices_lock); 565 566 mutex_lock(&clients_lock); 567 list_add_tail(&client->list, &clients); 568 mutex_unlock(&clients_lock); 569 570 return 0; 571 } 572 EXPORT_SYMBOL(host1x_client_register); 573 574 int host1x_client_unregister(struct host1x_client *client) 575 { 576 struct host1x_client *c; 577 struct host1x *host1x; 578 int err; 579 580 mutex_lock(&devices_lock); 581 582 list_for_each_entry(host1x, &devices, list) { 583 err = host1x_del_client(host1x, client); 584 if (!err) { 585 mutex_unlock(&devices_lock); 586 return 0; 587 } 588 } 589 590 mutex_unlock(&devices_lock); 591 mutex_lock(&clients_lock); 592 593 list_for_each_entry(c, &clients, list) { 594 if (c == client) { 595 list_del_init(&c->list); 596 break; 597 } 598 } 599 600 mutex_unlock(&clients_lock); 601 602 return 0; 603 } 604 EXPORT_SYMBOL(host1x_client_unregister); 605