drivers/sh/maple/maple.c

   1 /*
   2  * Core maple bus functionality
   3  *
   4  *  Copyright (C) 2007, 2008 Adrian McMenamin
   5  *
   6  * Based on 2.4 code by:
   7  *
   8  *  Copyright (C) 2000-2001 YAEGASHI Takeshi
   9  *  Copyright (C) 2001 M. R. Brown
  10  *  Copyright (C) 2001 Paul Mundt
  11  *
  12  * and others.
  13  *
  14  * This file is subject to the terms and conditions of the GNU General Public
  15  * License.  See the file "COPYING" in the main directory of this archive
  16  * for more details.
  17  */
  18 #include <linux/init.h>
  19 #include <linux/kernel.h>
  20 #include <linux/device.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/list.h>
  23 #include <linux/io.h>
  24 #include <linux/slab.h>
  25 #include <linux/maple.h>
  26 #include <linux/dma-mapping.h>
  27 #include <asm/cacheflush.h>
  28 #include <asm/dma.h>
  29 #include <asm/io.h>
  30 #include <asm/mach/dma.h>
  31 #include <asm/mach/sysasic.h>
  32 #include <asm/mach/maple.h>
  33 #include <linux/delay.h>
  34
  35 MODULE_AUTHOR("Yaegshi Takeshi, Paul Mundt, M.R. Brown, Adrian McMenamin");
  36 MODULE_DESCRIPTION("Maple bus driver for Dreamcast");
  37 MODULE_LICENSE("GPL v2");
  38 MODULE_SUPPORTED_DEVICE("{{SEGA, Dreamcast/Maple}}");
  39
  40 static void maple_dma_handler(struct work_struct *work);
  41 static void maple_vblank_handler(struct work_struct *work);
  42
  43 static DECLARE_WORK(maple_dma_process, maple_dma_handler);
  44 static DECLARE_WORK(maple_vblank_process, maple_vblank_handler);
  45
  46 static LIST_HEAD(maple_waitq);
  47 static LIST_HEAD(maple_sentq);
  48
  49 static DEFINE_MUTEX(maple_list_lock);
  50
  51 static struct maple_driver maple_dummy_driver;
  52 static struct device maple_bus;
  53 static int subdevice_map[MAPLE_PORTS];
  54 static unsigned long *maple_sendbuf, *maple_sendptr, *maple_lastptr;
  55 static unsigned long maple_pnp_time;
  56 static int started, scanning, liststatus, fullscan;
  57 static struct kmem_cache *maple_queue_cache;
  58
  59 struct maple_device_specify {
  60         int port;
  61         int unit;
  62 };
  63
  64 static bool checked[4];
  65 static struct maple_device *baseunits[4];
  66
  67 /**
  68  *  maple_driver_register - register a device driver
  69  *  automatically makes the driver bus a maple bus
  70  *  @drv: the driver to be registered
  71  */
  72 int maple_driver_register(struct device_driver *drv)
  73 {
  74         if (!drv)
  75                 return -EINVAL;
  76         drv->bus = &maple_bus_type;
  77         return driver_register(drv);
  78 }
  79 EXPORT_SYMBOL_GPL(maple_driver_register);
  80
  81 /* set hardware registers to enable next round of dma */
  82 static void maplebus_dma_reset(void)
  83 {
  84         ctrl_outl(MAPLE_MAGIC, MAPLE_RESET);
  85         /* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */
  86         ctrl_outl(1, MAPLE_TRIGTYPE);
  87         ctrl_outl(MAPLE_2MBPS | MAPLE_TIMEOUT(50000), MAPLE_SPEED);
  88         ctrl_outl(PHYSADDR(maple_sendbuf), MAPLE_DMAADDR);
  89         ctrl_outl(1, MAPLE_ENABLE);
  90 }
  91
  92 /**
  93  * maple_getcond_callback - setup handling MAPLE_COMMAND_GETCOND
  94  * @dev: device responding
  95  * @callback: handler callback
  96  * @interval: interval in jiffies between callbacks
  97  * @function: the function code for the device
  98  */
  99 void maple_getcond_callback(struct maple_device *dev,
 100                         void (*callback) (struct mapleq *mq),
 101                         unsigned long interval, unsigned long function)
 102 {
 103         dev->callback = callback;
 104         dev->interval = interval;
 105         dev->function = cpu_to_be32(function);
 106         dev->when = jiffies;
 107 }
 108 EXPORT_SYMBOL_GPL(maple_getcond_callback);
 109
 110 static int maple_dma_done(void)
 111 {
 112         return (ctrl_inl(MAPLE_STATE) & 1) == 0;
 113 }
 114
 115 static void maple_release_device(struct device *dev)
 116 {
 117         struct maple_device *mdev;
 118         struct mapleq *mq;
 119         if (!dev)
 120                 return;
 121         mdev = to_maple_dev(dev);
 122         mq = mdev->mq;
 123         if (mq) {
 124                 if (mq->recvbufdcsp)
 125                         kmem_cache_free(maple_queue_cache, mq->recvbufdcsp);
 126                 kfree(mq);
 127                 mq = NULL;
 128         }
 129         kfree(mdev);
 130 }
 131
 132 /**
 133  * maple_add_packet - add a single instruction to the queue
 134  * @mq: instruction to add to waiting queue
 135  */
 136 void maple_add_packet(struct mapleq *mq)
 137 {
 138         mutex_lock(&maple_list_lock);
 139         list_add(&mq->list, &maple_waitq);
 140         mutex_unlock(&maple_list_lock);
 141 }
 142 EXPORT_SYMBOL_GPL(maple_add_packet);
 143
 144 static struct mapleq *maple_allocq(struct maple_device *mdev)
 145 {
 146         struct mapleq *mq;
 147
 148         mq = kmalloc(sizeof(*mq), GFP_KERNEL);
 149         if (!mq)
 150                 return NULL;
 151
 152         mq->dev = mdev;
 153         mq->recvbufdcsp = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
 154         mq->recvbuf = (void *) P2SEGADDR(mq->recvbufdcsp);
 155         if (!mq->recvbuf) {
 156                 kfree(mq);
 157                 return NULL;
 158         }
 159
 160         return mq;
 161 }
 162
 163 static struct maple_device *maple_alloc_dev(int port, int unit)
 164 {
 165         struct maple_device *mdev;
 166
 167         mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
 168         if (!mdev)
 169                 return NULL;
 170
 171         mdev->port = port;
 172         mdev->unit = unit;
 173         mdev->mq = maple_allocq(mdev);
 174
 175         if (!mdev->mq) {
 176                 kfree(mdev);
 177                 return NULL;
 178         }
 179         mdev->dev.bus = &maple_bus_type;
 180         mdev->dev.parent = &maple_bus;
 181         mdev->function = 0;
 182         return mdev;
 183 }
 184
 185 static void maple_free_dev(struct maple_device *mdev)
 186 {
 187         if (!mdev)
 188                 return;
 189         if (mdev->mq) {
 190                 if (mdev->mq->recvbufdcsp)
 191                         kmem_cache_free(maple_queue_cache,
 192                                 mdev->mq->recvbufdcsp);
 193                 kfree(mdev->mq);
 194         }
 195         kfree(mdev);
 196 }
 197
 198 /* process the command queue into a maple command block
 199  * terminating command has bit 32 of first long set to 0
 200  */
 201 static void maple_build_block(struct mapleq *mq)
 202 {
 203         int port, unit, from, to, len;
 204         unsigned long *lsendbuf = mq->sendbuf;
 205
 206         port = mq->dev->port & 3;
 207         unit = mq->dev->unit;
 208         len = mq->length;
 209         from = port << 6;
 210         to = (port << 6) | (unit > 0 ? (1 << (unit - 1)) & 0x1f : 0x20);
 211
 212         *maple_lastptr &= 0x7fffffff;
 213         maple_lastptr = maple_sendptr;
 214
 215         *maple_sendptr++ = (port << 16) | len | 0x80000000;
 216         *maple_sendptr++ = PHYSADDR(mq->recvbuf);
 217         *maple_sendptr++ =
 218             mq->command | (to << 8) | (from << 16) | (len << 24);
 219
 220         while (len-- > 0)
 221                 *maple_sendptr++ = *lsendbuf++;
 222 }
 223
 224 /* build up command queue */
 225 static void maple_send(void)
 226 {
 227         int i;
 228         int maple_packets;
 229         struct mapleq *mq, *nmq;
 230
 231         if (!list_empty(&maple_sentq))
 232                 return;
 233         if (list_empty(&maple_waitq) || !maple_dma_done())
 234                 return;
 235         maple_packets = 0;
 236         maple_sendptr = maple_lastptr = maple_sendbuf;
 237         list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
 238                 maple_build_block(mq);
 239                 list_move(&mq->list, &maple_sentq);
 240                 if (maple_packets++ > MAPLE_MAXPACKETS)
 241                         break;
 242         }
 243         if (maple_packets > 0) {
 244                 for (i = 0; i < (1 << MAPLE_DMA_PAGES); i++)
 245                         dma_cache_sync(0, maple_sendbuf + i * PAGE_SIZE,
 246                                        PAGE_SIZE, DMA_BIDIRECTIONAL);
 247         }
 248 }
 249
 250 static int attach_matching_maple_driver(struct device_driver *driver,
 251                                         void *devptr)
 252 {
 253         struct maple_driver *maple_drv;
 254         struct maple_device *mdev;
 255
 256         mdev = devptr;
 257         maple_drv = to_maple_driver(driver);
 258         if (mdev->devinfo.function & be32_to_cpu(maple_drv->function)) {
 259                 if (maple_drv->connect(mdev) == 0) {
 260                         mdev->driver = maple_drv;
 261                         return 1;
 262                 }
 263         }
 264         return 0;
 265 }
 266
 267 static void maple_detach_driver(struct maple_device *mdev)
 268 {
 269         if (!mdev)
 270                 return;
 271         if (mdev->driver) {
 272                 if (mdev->driver->disconnect)
 273                         mdev->driver->disconnect(mdev);
 274         }
 275         mdev->driver = NULL;
 276         device_unregister(&mdev->dev);
 277         mdev = NULL;
 278 }
 279
 280 /* process initial MAPLE_COMMAND_DEVINFO for each device or port */
 281 static void maple_attach_driver(struct maple_device *mdev)
 282 {
 283         char *p, *recvbuf;
 284         unsigned long function;
 285         int matched, retval;
 286
 287         recvbuf = mdev->mq->recvbuf;
 288         /* copy the data as individual elements in
 289         * case of memory optimisation */
 290         memcpy(&mdev->devinfo.function, recvbuf + 4, 4);
 291         memcpy(&mdev->devinfo.function_data[0], recvbuf + 8, 12);
 292         memcpy(&mdev->devinfo.area_code, recvbuf + 20, 1);
 293         memcpy(&mdev->devinfo.connector_direction, recvbuf + 21, 1);
 294         memcpy(&mdev->devinfo.product_name[0], recvbuf + 22, 30);
 295         memcpy(&mdev->devinfo.product_licence[0], recvbuf + 52, 60);
 296         memcpy(&mdev->devinfo.standby_power, recvbuf + 112, 2);
 297         memcpy(&mdev->devinfo.max_power, recvbuf + 114, 2);
 298         memcpy(mdev->product_name, mdev->devinfo.product_name, 30);
 299         mdev->product_name[30] = '\0';
 300         memcpy(mdev->product_licence, mdev->devinfo.product_licence, 60);
 301         mdev->product_licence[60] = '\0';
 302
 303         for (p = mdev->product_name + 29; mdev->product_name <= p; p--)
 304                 if (*p == ' ')
 305                         *p = '\0';
 306                 else
 307                         break;
 308         for (p = mdev->product_licence + 59; mdev->product_licence <= p; p--)
 309                 if (*p == ' ')
 310                         *p = '\0';
 311                 else
 312                         break;
 313
 314         printk(KERN_INFO "Maple device detected: %s\n",
 315                 mdev->product_name);
 316         printk(KERN_INFO "Maple device: %s\n", mdev->product_licence);
 317
 318         function = be32_to_cpu(mdev->devinfo.function);
 319
 320         if (function > 0x200) {
 321                 /* Do this silently - as not a real device */
 322                 function = 0;
 323                 mdev->driver = &maple_dummy_driver;
 324                 sprintf(mdev->dev.bus_id, "%d:0.port", mdev->port);
 325         } else {
 326                 printk(KERN_INFO
 327                         "Maple bus at (%d, %d): Function 0x%lX\n",
 328                         mdev->port, mdev->unit, function);
 329
 330                 matched =
 331                     bus_for_each_drv(&maple_bus_type, NULL, mdev,
 332                                      attach_matching_maple_driver);
 333
 334                 if (matched == 0) {
 335                         /* Driver does not exist yet */
 336                         printk(KERN_INFO
 337                                 "No maple driver found.\n");
 338                         mdev->driver = &maple_dummy_driver;
 339                 }
 340                 sprintf(mdev->dev.bus_id, "%d:0%d.%lX", mdev->port,
 341                         mdev->unit, function);
 342         }
 343         mdev->function = function;
 344         mdev->dev.release = &maple_release_device;
 345         retval = device_register(&mdev->dev);
 346         if (retval) {
 347                 printk(KERN_INFO
 348                 "Maple bus: Attempt to register device"
 349                 " (%x, %x) failed.\n",
 350                 mdev->port, mdev->unit);
 351                 maple_free_dev(mdev);
 352                 mdev = NULL;
 353                 return;
 354         }
 355 }
 356
 357 /*
 358  * if device has been registered for the given
 359  * port and unit then return 1 - allows identification
 360  * of which devices need to be attached or detached
 361  */
 362 static int detach_maple_device(struct device *device, void *portptr)
 363 {
 364         struct maple_device_specify *ds;
 365         struct maple_device *mdev;
 366
 367         ds = portptr;
 368         mdev = to_maple_dev(device);
 369         if (mdev->port == ds->port && mdev->unit == ds->unit)
 370                 return 1;
 371         return 0;
 372 }
 373
 374 static int setup_maple_commands(struct device *device, void *ignored)
 375 {
 376         struct maple_device *maple_dev = to_maple_dev(device);
 377
 378         if ((maple_dev->interval > 0)
 379             && time_after(jiffies, maple_dev->when)) {
 380                 maple_dev->when = jiffies + maple_dev->interval;
 381                 maple_dev->mq->command = MAPLE_COMMAND_GETCOND;
 382                 maple_dev->mq->sendbuf = &maple_dev->function;
 383                 maple_dev->mq->length = 1;
 384                 maple_add_packet(maple_dev->mq);
 385                 liststatus++;
 386         } else {
 387                 if (time_after(jiffies, maple_pnp_time)) {
 388                         maple_dev->mq->command = MAPLE_COMMAND_DEVINFO;
 389                         maple_dev->mq->length = 0;
 390                         maple_add_packet(maple_dev->mq);
 391                         liststatus++;
 392                 }
 393         }
 394
 395         return 0;
 396 }
 397
 398 /* VBLANK bottom half - implemented via workqueue */
 399 static void maple_vblank_handler(struct work_struct *work)
 400 {
 401         if (!maple_dma_done())
 402                 return;
 403         if (!list_empty(&maple_sentq))
 404                 return;
 405         ctrl_outl(0, MAPLE_ENABLE);
 406         liststatus = 0;
 407         bus_for_each_dev(&maple_bus_type, NULL, NULL,
 408                          setup_maple_commands);
 409         if (time_after(jiffies, maple_pnp_time))
 410                 maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
 411         if (liststatus && list_empty(&maple_sentq)) {
 412                 INIT_LIST_HEAD(&maple_sentq);
 413                 maple_send();
 414         }
 415         maplebus_dma_reset();
 416 }
 417
 418 /* handle devices added via hotplugs - placing them on queue for DEVINFO*/
 419 static void maple_map_subunits(struct maple_device *mdev, int submask)
 420 {
 421         int retval, k, devcheck;
 422         struct maple_device *mdev_add;
 423         struct maple_device_specify ds;
 424
 425         for (k = 0; k < 5; k++) {
 426                 ds.port = mdev->port;
 427                 ds.unit = k + 1;
 428                 retval =
 429                     bus_for_each_dev(&maple_bus_type, NULL, &ds,
 430                                      detach_maple_device);
 431                 if (retval) {
 432                         submask = submask >> 1;
 433                         continue;
 434                 }
 435                 devcheck = submask & 0x01;
 436                 if (devcheck) {
 437                         mdev_add = maple_alloc_dev(mdev->port, k + 1);
 438                         if (!mdev_add)
 439                                 return;
 440                         mdev_add->mq->command = MAPLE_COMMAND_DEVINFO;
 441                         mdev_add->mq->length = 0;
 442                         maple_add_packet(mdev_add->mq);
 443                         scanning = 1;
 444                 }
 445                 submask = submask >> 1;
 446         }
 447 }
 448
 449 /* mark a device as removed */
 450 static void maple_clean_submap(struct maple_device *mdev)
 451 {
 452         int killbit;
 453
 454         killbit = (mdev->unit > 0 ? (1 << (mdev->unit - 1)) & 0x1f : 0x20);
 455         killbit = ~killbit;
 456         killbit &= 0xFF;
 457         subdevice_map[mdev->port] = subdevice_map[mdev->port] & killbit;
 458 }
 459
 460 /* handle empty port or hotplug removal */
 461 static void maple_response_none(struct maple_device *mdev,
 462                                 struct mapleq *mq)
 463 {
 464         if (mdev->unit != 0) {
 465                 list_del(&mq->list);
 466                 maple_clean_submap(mdev);
 467                 printk(KERN_INFO
 468                        "Maple bus device detaching at (%d, %d)\n",
 469                        mdev->port, mdev->unit);
 470                 maple_detach_driver(mdev);
 471                 return;
 472         }
 473         if (!started || !fullscan) {
 474                 if (checked[mdev->port] == false) {
 475                         checked[mdev->port] = true;
 476                         printk(KERN_INFO "No maple devices attached"
 477                                 " to port %d\n", mdev->port);
 478                 }
 479                 return;
 480         }
 481         maple_clean_submap(mdev);
 482 }
 483
 484 /* preprocess hotplugs or scans */
 485 static void maple_response_devinfo(struct maple_device *mdev,
 486                                    char *recvbuf)
 487 {
 488         char submask;
 489         if (!started || (scanning == 2) || !fullscan) {
 490                 if ((mdev->unit == 0) && (checked[mdev->port] == false)) {
 491                         checked[mdev->port] = true;
 492                         maple_attach_driver(mdev);
 493                 } else {
 494                         if (mdev->unit != 0)
 495                                 maple_attach_driver(mdev);
 496                 }
 497                 return;
 498         }
 499         if (mdev->unit == 0) {
 500                 submask = recvbuf[2] & 0x1F;
 501                 if (submask ^ subdevice_map[mdev->port]) {
 502                         maple_map_subunits(mdev, submask);
 503                         subdevice_map[mdev->port] = submask;
 504                 }
 505         }
 506 }
 507
 508 /* maple dma end bottom half - implemented via workqueue */
 509 static void maple_dma_handler(struct work_struct *work)
 510 {
 511         struct mapleq *mq, *nmq;
 512         struct maple_device *dev;
 513         char *recvbuf;
 514         enum maple_code code;
 515         int i;
 516
 517         if (!maple_dma_done())
 518                 return;
 519         ctrl_outl(0, MAPLE_ENABLE);
 520         if (!list_empty(&maple_sentq)) {
 521                 list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
 522                         recvbuf = mq->recvbuf;
 523                         code = recvbuf[0];
 524                         dev = mq->dev;
 525                         switch (code) {
 526                         case MAPLE_RESPONSE_NONE:
 527                                 maple_response_none(dev, mq);
 528                                 break;
 529
 530                         case MAPLE_RESPONSE_DEVINFO:
 531                                 maple_response_devinfo(dev, recvbuf);
 532                                 break;
 533
 534                         case MAPLE_RESPONSE_DATATRF:
 535                                 if (dev->callback)
 536                                         dev->callback(mq);
 537                                 break;
 538
 539                         case MAPLE_RESPONSE_FILEERR:
 540                         case MAPLE_RESPONSE_AGAIN:
 541                         case MAPLE_RESPONSE_BADCMD:
 542                         case MAPLE_RESPONSE_BADFUNC:
 543                                 printk(KERN_DEBUG
 544                                        "Maple non-fatal error 0x%X\n",
 545                                        code);
 546                                 break;
 547
 548                         case MAPLE_RESPONSE_ALLINFO:
 549                                 printk(KERN_DEBUG
 550                                        "Maple - extended device information"
 551                                         " not supported\n");
 552                                 break;
 553
 554                         case MAPLE_RESPONSE_OK:
 555                                 break;
 556
 557                         default:
 558                                 break;
 559                         }
 560                 }
 561                 INIT_LIST_HEAD(&maple_sentq);
 562                 if (scanning == 1) {
 563                         maple_send();
 564                         scanning = 2;
 565                 } else
 566                         scanning = 0;
 567
 568                 if (!fullscan) {
 569                         fullscan = 1;
 570                         for (i = 0; i < MAPLE_PORTS; i++) {
 571                                 if (checked[i] == false) {
 572                                         fullscan = 0;
 573                                         dev = baseunits[i];
 574                                         dev->mq->command =
 575                                                 MAPLE_COMMAND_DEVINFO;
 576                                         dev->mq->length = 0;
 577                                         maple_add_packet(dev->mq);
 578                                 }
 579                         }
 580                 }
 581                 if (started == 0)
 582                         started = 1;
 583         }
 584         maplebus_dma_reset();
 585 }
 586
 587 static irqreturn_t maplebus_dma_interrupt(int irq, void *dev_id)
 588 {
 589         /* Load everything into the bottom half */
 590         schedule_work(&maple_dma_process);
 591         return IRQ_HANDLED;
 592 }
 593
 594 static irqreturn_t maplebus_vblank_interrupt(int irq, void *dev_id)
 595 {
 596         schedule_work(&maple_vblank_process);
 597         return IRQ_HANDLED;
 598 }
 599
 600 static int maple_set_dma_interrupt_handler(void)
 601 {
 602         return request_irq(HW_EVENT_MAPLE_DMA, maplebus_dma_interrupt,
 603                 IRQF_SHARED, "maple bus DMA", &maple_dummy_driver);
 604 }
 605
 606 static int maple_set_vblank_interrupt_handler(void)
 607 {
 608         return request_irq(HW_EVENT_VSYNC, maplebus_vblank_interrupt,
 609                 IRQF_SHARED, "maple bus VBLANK", &maple_dummy_driver);
 610 }
 611
 612 static int maple_get_dma_buffer(void)
 613 {
 614         maple_sendbuf =
 615             (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
 616                                       MAPLE_DMA_PAGES);
 617         if (!maple_sendbuf)
 618                 return -ENOMEM;
 619         return 0;
 620 }
 621
 622 static int match_maple_bus_driver(struct device *devptr,
 623                                   struct device_driver *drvptr)
 624 {
 625         struct maple_driver *maple_drv;
 626         struct maple_device *maple_dev;
 627
 628         maple_drv = container_of(drvptr, struct maple_driver, drv);
 629         maple_dev = container_of(devptr, struct maple_device, dev);
 630         /* Trap empty port case */
 631         if (maple_dev->devinfo.function == 0xFFFFFFFF)
 632                 return 0;
 633         else if (maple_dev->devinfo.function &
 634                  be32_to_cpu(maple_drv->function))
 635                 return 1;
 636         return 0;
 637 }
 638
 639 static int maple_bus_uevent(struct device *dev,
 640                             struct kobj_uevent_env *env)
 641 {
 642         return 0;
 643 }
 644
 645 static void maple_bus_release(struct device *dev)
 646 {
 647 }
 648
 649 static struct maple_driver maple_dummy_driver = {
 650         .drv = {
 651                 .name = "maple_dummy_driver",
 652                 .bus = &maple_bus_type,
 653         },
 654 };
 655
 656 struct bus_type maple_bus_type = {
 657         .name = "maple",
 658         .match = match_maple_bus_driver,
 659         .uevent = maple_bus_uevent,
 660 };
 661 EXPORT_SYMBOL_GPL(maple_bus_type);
 662
 663 static struct device maple_bus = {
 664         .bus_id = "maple",
 665         .release = maple_bus_release,
 666 };
 667
 668 static int __init maple_bus_init(void)
 669 {
 670         int retval, i;
 671         struct maple_device *mdev[MAPLE_PORTS];
 672         ctrl_outl(0, MAPLE_STATE);
 673
 674         retval = device_register(&maple_bus);
 675         if (retval)
 676                 goto cleanup;
 677
 678         retval = bus_register(&maple_bus_type);
 679         if (retval)
 680                 goto cleanup_device;
 681
 682         retval = driver_register(&maple_dummy_driver.drv);
 683         if (retval)
 684                 goto cleanup_bus;
 685
 686         /* allocate memory for maple bus dma */
 687         retval = maple_get_dma_buffer();
 688         if (retval) {
 689                 printk(KERN_INFO
 690                        "Maple bus: Failed to allocate Maple DMA buffers\n");
 691                 goto cleanup_basic;
 692         }
 693
 694         /* set up DMA interrupt handler */
 695         retval = maple_set_dma_interrupt_handler();
 696         if (retval) {
 697                 printk(KERN_INFO
 698                        "Maple bus: Failed to grab maple DMA IRQ\n");
 699                 goto cleanup_dma;
 700         }
 701
 702         /* set up VBLANK interrupt handler */
 703         retval = maple_set_vblank_interrupt_handler();
 704         if (retval) {
 705                 printk(KERN_INFO "Maple bus: Failed to grab VBLANK IRQ\n");
 706                 goto cleanup_irq;
 707         }
 708
 709         maple_queue_cache =
 710             kmem_cache_create("maple_queue_cache", 0x400, 0,
 711                               SLAB_POISON|SLAB_HWCACHE_ALIGN, NULL);
 712
 713         if (!maple_queue_cache)
 714                 goto cleanup_bothirqs;
 715
 716         /* setup maple ports */
 717         for (i = 0; i < MAPLE_PORTS; i++) {
 718                 checked[i] = false;
 719                 mdev[i] = maple_alloc_dev(i, 0);
 720                 baseunits[i] = mdev[i];
 721                 if (!mdev[i]) {
 722                         while (i-- > 0)
 723                                 maple_free_dev(mdev[i]);
 724                         goto cleanup_cache;
 725                 }
 726                 mdev[i]->mq->command = MAPLE_COMMAND_DEVINFO;
 727                 mdev[i]->mq->length = 0;
 728                 maple_add_packet(mdev[i]->mq);
 729                 subdevice_map[i] = 0;
 730         }
 731
 732         /* setup maplebus hardware */
 733         maplebus_dma_reset();
 734         /* initial detection */
 735         maple_send();
 736         maple_pnp_time = jiffies;
 737         printk(KERN_INFO "Maple bus core now registered.\n");
 738
 739         return 0;
 740
 741 cleanup_cache:
 742         kmem_cache_destroy(maple_queue_cache);
 743
 744 cleanup_bothirqs:
 745         free_irq(HW_EVENT_VSYNC, 0);
 746
 747 cleanup_irq:
 748         free_irq(HW_EVENT_MAPLE_DMA, 0);
 749
 750 cleanup_dma:
 751         free_pages((unsigned long) maple_sendbuf, MAPLE_DMA_PAGES);
 752
 753 cleanup_basic:
 754         driver_unregister(&maple_dummy_driver.drv);
 755
 756 cleanup_bus:
 757         bus_unregister(&maple_bus_type);
 758
 759 cleanup_device:
 760         device_unregister(&maple_bus);
 761
 762 cleanup:
 763         printk(KERN_INFO "Maple bus registration failed\n");
 764         return retval;
 765 }
 766 /* Push init to later to ensure hardware gets detected */
 767 fs_initcall(maple_bus_init);