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 #include <linux/of_device.h> 22 23 #include "bus.h" 24 #include "dev.h" 25 26 static DEFINE_MUTEX(clients_lock); 27 static LIST_HEAD(clients); 28 29 static DEFINE_MUTEX(drivers_lock); 30 static LIST_HEAD(drivers); 31 32 static DEFINE_MUTEX(devices_lock); 33 static LIST_HEAD(devices); 34 35 struct host1x_subdev { 36 struct host1x_client *client; 37 struct device_node *np; 38 struct list_head list; 39 }; 40 41 /** 42 * host1x_subdev_add() - add a new subdevice with an associated device node 43 */ 44 static int host1x_subdev_add(struct host1x_device *device, 45 struct device_node *np) 46 { 47 struct host1x_subdev *subdev; 48 49 subdev = kzalloc(sizeof(*subdev), GFP_KERNEL); 50 if (!subdev) 51 return -ENOMEM; 52 53 INIT_LIST_HEAD(&subdev->list); 54 subdev->np = of_node_get(np); 55 56 mutex_lock(&device->subdevs_lock); 57 list_add_tail(&subdev->list, &device->subdevs); 58 mutex_unlock(&device->subdevs_lock); 59 60 return 0; 61 } 62 63 /** 64 * host1x_subdev_del() - remove subdevice 65 */ 66 static void host1x_subdev_del(struct host1x_subdev *subdev) 67 { 68 list_del(&subdev->list); 69 of_node_put(subdev->np); 70 kfree(subdev); 71 } 72 73 /** 74 * host1x_device_parse_dt() - scan device tree and add matching subdevices 75 */ 76 static int host1x_device_parse_dt(struct host1x_device *device, 77 struct host1x_driver *driver) 78 { 79 struct device_node *np; 80 int err; 81 82 for_each_child_of_node(device->dev.parent->of_node, np) { 83 if (of_match_node(driver->subdevs, np) && 84 of_device_is_available(np)) { 85 err = host1x_subdev_add(device, np); 86 if (err < 0) { 87 of_node_put(np); 88 return err; 89 } 90 } 91 } 92 93 return 0; 94 } 95 96 static void host1x_subdev_register(struct host1x_device *device, 97 struct host1x_subdev *subdev, 98 struct host1x_client *client) 99 { 100 int err; 101 102 /* 103 * Move the subdevice to the list of active (registered) subdevices 104 * and associate it with a client. At the same time, associate the 105 * client with its parent device. 106 */ 107 mutex_lock(&device->subdevs_lock); 108 mutex_lock(&device->clients_lock); 109 list_move_tail(&client->list, &device->clients); 110 list_move_tail(&subdev->list, &device->active); 111 client->parent = &device->dev; 112 subdev->client = client; 113 mutex_unlock(&device->clients_lock); 114 mutex_unlock(&device->subdevs_lock); 115 116 if (list_empty(&device->subdevs)) { 117 err = device_add(&device->dev); 118 if (err < 0) 119 dev_err(&device->dev, "failed to add: %d\n", err); 120 else 121 device->registered = true; 122 } 123 } 124 125 static void __host1x_subdev_unregister(struct host1x_device *device, 126 struct host1x_subdev *subdev) 127 { 128 struct host1x_client *client = subdev->client; 129 130 /* 131 * If all subdevices have been activated, we're about to remove the 132 * first active subdevice, so unload the driver first. 133 */ 134 if (list_empty(&device->subdevs)) { 135 if (device->registered) { 136 device->registered = false; 137 device_del(&device->dev); 138 } 139 } 140 141 /* 142 * Move the subdevice back to the list of idle subdevices and remove 143 * it from list of clients. 144 */ 145 mutex_lock(&device->clients_lock); 146 subdev->client = NULL; 147 client->parent = NULL; 148 list_move_tail(&subdev->list, &device->subdevs); 149 /* 150 * XXX: Perhaps don't do this here, but rather explicitly remove it 151 * when the device is about to be deleted. 152 * 153 * This is somewhat complicated by the fact that this function is 154 * used to remove the subdevice when a client is unregistered but 155 * also when the composite device is about to be removed. 156 */ 157 list_del_init(&client->list); 158 mutex_unlock(&device->clients_lock); 159 } 160 161 static void host1x_subdev_unregister(struct host1x_device *device, 162 struct host1x_subdev *subdev) 163 { 164 mutex_lock(&device->subdevs_lock); 165 __host1x_subdev_unregister(device, subdev); 166 mutex_unlock(&device->subdevs_lock); 167 } 168 169 int host1x_device_init(struct host1x_device *device) 170 { 171 struct host1x_client *client; 172 int err; 173 174 mutex_lock(&device->clients_lock); 175 176 list_for_each_entry(client, &device->clients, list) { 177 if (client->ops && client->ops->init) { 178 err = client->ops->init(client); 179 if (err < 0) { 180 dev_err(&device->dev, 181 "failed to initialize %s: %d\n", 182 dev_name(client->dev), err); 183 mutex_unlock(&device->clients_lock); 184 return err; 185 } 186 } 187 } 188 189 mutex_unlock(&device->clients_lock); 190 191 return 0; 192 } 193 EXPORT_SYMBOL(host1x_device_init); 194 195 int host1x_device_exit(struct host1x_device *device) 196 { 197 struct host1x_client *client; 198 int err; 199 200 mutex_lock(&device->clients_lock); 201 202 list_for_each_entry_reverse(client, &device->clients, list) { 203 if (client->ops && client->ops->exit) { 204 err = client->ops->exit(client); 205 if (err < 0) { 206 dev_err(&device->dev, 207 "failed to cleanup %s: %d\n", 208 dev_name(client->dev), err); 209 mutex_unlock(&device->clients_lock); 210 return err; 211 } 212 } 213 } 214 215 mutex_unlock(&device->clients_lock); 216 217 return 0; 218 } 219 EXPORT_SYMBOL(host1x_device_exit); 220 221 static int host1x_add_client(struct host1x *host1x, 222 struct host1x_client *client) 223 { 224 struct host1x_device *device; 225 struct host1x_subdev *subdev; 226 227 mutex_lock(&host1x->devices_lock); 228 229 list_for_each_entry(device, &host1x->devices, list) { 230 list_for_each_entry(subdev, &device->subdevs, list) { 231 if (subdev->np == client->dev->of_node) { 232 host1x_subdev_register(device, subdev, client); 233 mutex_unlock(&host1x->devices_lock); 234 return 0; 235 } 236 } 237 } 238 239 mutex_unlock(&host1x->devices_lock); 240 return -ENODEV; 241 } 242 243 static int host1x_del_client(struct host1x *host1x, 244 struct host1x_client *client) 245 { 246 struct host1x_device *device, *dt; 247 struct host1x_subdev *subdev; 248 249 mutex_lock(&host1x->devices_lock); 250 251 list_for_each_entry_safe(device, dt, &host1x->devices, list) { 252 list_for_each_entry(subdev, &device->active, list) { 253 if (subdev->client == client) { 254 host1x_subdev_unregister(device, subdev); 255 mutex_unlock(&host1x->devices_lock); 256 return 0; 257 } 258 } 259 } 260 261 mutex_unlock(&host1x->devices_lock); 262 return -ENODEV; 263 } 264 265 static int host1x_device_match(struct device *dev, struct device_driver *drv) 266 { 267 return strcmp(dev_name(dev), drv->name) == 0; 268 } 269 270 static int host1x_device_probe(struct device *dev) 271 { 272 struct host1x_driver *driver = to_host1x_driver(dev->driver); 273 struct host1x_device *device = to_host1x_device(dev); 274 275 if (driver->probe) 276 return driver->probe(device); 277 278 return 0; 279 } 280 281 static int host1x_device_remove(struct device *dev) 282 { 283 struct host1x_driver *driver = to_host1x_driver(dev->driver); 284 struct host1x_device *device = to_host1x_device(dev); 285 286 if (driver->remove) 287 return driver->remove(device); 288 289 return 0; 290 } 291 292 static void host1x_device_shutdown(struct device *dev) 293 { 294 struct host1x_driver *driver = to_host1x_driver(dev->driver); 295 struct host1x_device *device = to_host1x_device(dev); 296 297 if (driver->shutdown) 298 driver->shutdown(device); 299 } 300 301 static const struct dev_pm_ops host1x_device_pm_ops = { 302 .suspend = pm_generic_suspend, 303 .resume = pm_generic_resume, 304 .freeze = pm_generic_freeze, 305 .thaw = pm_generic_thaw, 306 .poweroff = pm_generic_poweroff, 307 .restore = pm_generic_restore, 308 }; 309 310 struct bus_type host1x_bus_type = { 311 .name = "host1x", 312 .match = host1x_device_match, 313 .probe = host1x_device_probe, 314 .remove = host1x_device_remove, 315 .shutdown = host1x_device_shutdown, 316 .pm = &host1x_device_pm_ops, 317 }; 318 319 static void __host1x_device_del(struct host1x_device *device) 320 { 321 struct host1x_subdev *subdev, *sd; 322 struct host1x_client *client, *cl; 323 324 mutex_lock(&device->subdevs_lock); 325 326 /* unregister subdevices */ 327 list_for_each_entry_safe(subdev, sd, &device->active, list) { 328 /* 329 * host1x_subdev_unregister() will remove the client from 330 * any lists, so we'll need to manually add it back to the 331 * list of idle clients. 332 * 333 * XXX: Alternatively, perhaps don't remove the client from 334 * any lists in host1x_subdev_unregister() and instead do 335 * that explicitly from host1x_unregister_client()? 336 */ 337 client = subdev->client; 338 339 __host1x_subdev_unregister(device, subdev); 340 341 /* add the client to the list of idle clients */ 342 mutex_lock(&clients_lock); 343 list_add_tail(&client->list, &clients); 344 mutex_unlock(&clients_lock); 345 } 346 347 /* remove subdevices */ 348 list_for_each_entry_safe(subdev, sd, &device->subdevs, list) 349 host1x_subdev_del(subdev); 350 351 mutex_unlock(&device->subdevs_lock); 352 353 /* move clients to idle list */ 354 mutex_lock(&clients_lock); 355 mutex_lock(&device->clients_lock); 356 357 list_for_each_entry_safe(client, cl, &device->clients, list) 358 list_move_tail(&client->list, &clients); 359 360 mutex_unlock(&device->clients_lock); 361 mutex_unlock(&clients_lock); 362 363 /* finally remove the device */ 364 list_del_init(&device->list); 365 } 366 367 static void host1x_device_release(struct device *dev) 368 { 369 struct host1x_device *device = to_host1x_device(dev); 370 371 __host1x_device_del(device); 372 kfree(device); 373 } 374 375 static int host1x_device_add(struct host1x *host1x, 376 struct host1x_driver *driver) 377 { 378 struct host1x_client *client, *tmp; 379 struct host1x_subdev *subdev; 380 struct host1x_device *device; 381 int err; 382 383 device = kzalloc(sizeof(*device), GFP_KERNEL); 384 if (!device) 385 return -ENOMEM; 386 387 device_initialize(&device->dev); 388 389 mutex_init(&device->subdevs_lock); 390 INIT_LIST_HEAD(&device->subdevs); 391 INIT_LIST_HEAD(&device->active); 392 mutex_init(&device->clients_lock); 393 INIT_LIST_HEAD(&device->clients); 394 INIT_LIST_HEAD(&device->list); 395 device->driver = driver; 396 397 device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask; 398 device->dev.dma_mask = &device->dev.coherent_dma_mask; 399 dev_set_name(&device->dev, "%s", driver->driver.name); 400 of_dma_configure(&device->dev, host1x->dev->of_node); 401 device->dev.release = host1x_device_release; 402 device->dev.bus = &host1x_bus_type; 403 device->dev.parent = host1x->dev; 404 405 err = host1x_device_parse_dt(device, driver); 406 if (err < 0) { 407 kfree(device); 408 return err; 409 } 410 411 list_add_tail(&device->list, &host1x->devices); 412 413 mutex_lock(&clients_lock); 414 415 list_for_each_entry_safe(client, tmp, &clients, list) { 416 list_for_each_entry(subdev, &device->subdevs, list) { 417 if (subdev->np == client->dev->of_node) { 418 host1x_subdev_register(device, subdev, client); 419 break; 420 } 421 } 422 } 423 424 mutex_unlock(&clients_lock); 425 426 return 0; 427 } 428 429 /* 430 * Removes a device by first unregistering any subdevices and then removing 431 * itself from the list of devices. 432 * 433 * This function must be called with the host1x->devices_lock held. 434 */ 435 static void host1x_device_del(struct host1x *host1x, 436 struct host1x_device *device) 437 { 438 if (device->registered) { 439 device->registered = false; 440 device_del(&device->dev); 441 } 442 443 put_device(&device->dev); 444 } 445 446 static void host1x_attach_driver(struct host1x *host1x, 447 struct host1x_driver *driver) 448 { 449 struct host1x_device *device; 450 int err; 451 452 mutex_lock(&host1x->devices_lock); 453 454 list_for_each_entry(device, &host1x->devices, list) { 455 if (device->driver == driver) { 456 mutex_unlock(&host1x->devices_lock); 457 return; 458 } 459 } 460 461 err = host1x_device_add(host1x, driver); 462 if (err < 0) 463 dev_err(host1x->dev, "failed to allocate device: %d\n", err); 464 465 mutex_unlock(&host1x->devices_lock); 466 } 467 468 static void host1x_detach_driver(struct host1x *host1x, 469 struct host1x_driver *driver) 470 { 471 struct host1x_device *device, *tmp; 472 473 mutex_lock(&host1x->devices_lock); 474 475 list_for_each_entry_safe(device, tmp, &host1x->devices, list) 476 if (device->driver == driver) 477 host1x_device_del(host1x, device); 478 479 mutex_unlock(&host1x->devices_lock); 480 } 481 482 int host1x_register(struct host1x *host1x) 483 { 484 struct host1x_driver *driver; 485 486 mutex_lock(&devices_lock); 487 list_add_tail(&host1x->list, &devices); 488 mutex_unlock(&devices_lock); 489 490 mutex_lock(&drivers_lock); 491 492 list_for_each_entry(driver, &drivers, list) 493 host1x_attach_driver(host1x, driver); 494 495 mutex_unlock(&drivers_lock); 496 497 return 0; 498 } 499 500 int host1x_unregister(struct host1x *host1x) 501 { 502 struct host1x_driver *driver; 503 504 mutex_lock(&drivers_lock); 505 506 list_for_each_entry(driver, &drivers, list) 507 host1x_detach_driver(host1x, driver); 508 509 mutex_unlock(&drivers_lock); 510 511 mutex_lock(&devices_lock); 512 list_del_init(&host1x->list); 513 mutex_unlock(&devices_lock); 514 515 return 0; 516 } 517 518 int host1x_driver_register_full(struct host1x_driver *driver, 519 struct module *owner) 520 { 521 struct host1x *host1x; 522 523 INIT_LIST_HEAD(&driver->list); 524 525 mutex_lock(&drivers_lock); 526 list_add_tail(&driver->list, &drivers); 527 mutex_unlock(&drivers_lock); 528 529 mutex_lock(&devices_lock); 530 531 list_for_each_entry(host1x, &devices, list) 532 host1x_attach_driver(host1x, driver); 533 534 mutex_unlock(&devices_lock); 535 536 driver->driver.bus = &host1x_bus_type; 537 driver->driver.owner = owner; 538 539 return driver_register(&driver->driver); 540 } 541 EXPORT_SYMBOL(host1x_driver_register_full); 542 543 void host1x_driver_unregister(struct host1x_driver *driver) 544 { 545 driver_unregister(&driver->driver); 546 547 mutex_lock(&drivers_lock); 548 list_del_init(&driver->list); 549 mutex_unlock(&drivers_lock); 550 } 551 EXPORT_SYMBOL(host1x_driver_unregister); 552 553 int host1x_client_register(struct host1x_client *client) 554 { 555 struct host1x *host1x; 556 int err; 557 558 mutex_lock(&devices_lock); 559 560 list_for_each_entry(host1x, &devices, list) { 561 err = host1x_add_client(host1x, client); 562 if (!err) { 563 mutex_unlock(&devices_lock); 564 return 0; 565 } 566 } 567 568 mutex_unlock(&devices_lock); 569 570 mutex_lock(&clients_lock); 571 list_add_tail(&client->list, &clients); 572 mutex_unlock(&clients_lock); 573 574 return 0; 575 } 576 EXPORT_SYMBOL(host1x_client_register); 577 578 int host1x_client_unregister(struct host1x_client *client) 579 { 580 struct host1x_client *c; 581 struct host1x *host1x; 582 int err; 583 584 mutex_lock(&devices_lock); 585 586 list_for_each_entry(host1x, &devices, list) { 587 err = host1x_del_client(host1x, client); 588 if (!err) { 589 mutex_unlock(&devices_lock); 590 return 0; 591 } 592 } 593 594 mutex_unlock(&devices_lock); 595 mutex_lock(&clients_lock); 596 597 list_for_each_entry(c, &clients, list) { 598 if (c == client) { 599 list_del_init(&c->list); 600 break; 601 } 602 } 603 604 mutex_unlock(&clients_lock); 605 606 return 0; 607 } 608 EXPORT_SYMBOL(host1x_client_unregister); 609