git.oblomov.eu Git - linux-2.6/blob - drivers/sh/maple/maple.c

   1 /*
   2  * Core maple bus functionality
   3  *
   4  *  Copyright (C) 2007, 2008 Adrian McMenamin
   5  *  Copyright (C) 2001 - 2008 Paul Mundt
   6  *
   7  * Based on 2.4 code by:
   8  *
   9  *  Copyright (C) 2000-2001 YAEGASHI Takeshi
  10  *  Copyright (C) 2001 M. R. Brown
  11  *  Copyright (C) 2001 Paul Mundt
  12  *
  13  * and others.
  14  *
  15  * This file is subject to the terms and conditions of the GNU General Public
  16  * License.  See the file "COPYING" in the main directory of this archive
  17  * for more details.
  18  */
  19 #include <linux/init.h>
  20 #include <linux/kernel.h>
  21 #include <linux/device.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/list.h>
  24 #include <linux/io.h>
  25 #include <linux/slab.h>
  26 #include <linux/maple.h>
  27 #include <linux/dma-mapping.h>
  28 #include <linux/delay.h>
  29 #include <asm/cacheflush.h>
  30 #include <asm/dma.h>
  31 #include <asm/io.h>
  32 #include <mach/dma.h>
  33 #include <mach/sysasic.h>
  34
  35 MODULE_AUTHOR("Yaegashi 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 /* mutex to protect queue of waiting packets */
  50 static DEFINE_MUTEX(maple_wlist_lock);
  51
  52 static struct maple_driver maple_dummy_driver;
  53 static struct device maple_bus;
  54 static int subdevice_map[MAPLE_PORTS];
  55 static unsigned long *maple_sendbuf, *maple_sendptr, *maple_lastptr;
  56 static unsigned long maple_pnp_time;
  57 static int started, scanning, fullscan;
  58 static struct kmem_cache *maple_queue_cache;
  59
  60 struct maple_device_specify {
  61         int port;
  62         int unit;
  63 };
  64
  65 static bool checked[4];
  66 static struct maple_device *baseunits[4];
  67
  68 /**
  69  * maple_driver_register - register a maple driver
  70  * @drv: maple driver to be registered.
  71  *
  72  * Registers the passed in @drv, while updating the bus type.
  73  * Devices with matching function IDs will be automatically probed.
  74  */
  75 int maple_driver_register(struct maple_driver *drv)
  76 {
  77         if (!drv)
  78                 return -EINVAL;
  79
  80         drv->drv.bus = &maple_bus_type;
  81
  82         return driver_register(&drv->drv);
  83 }
  84 EXPORT_SYMBOL_GPL(maple_driver_register);
  85
  86 /**
  87  * maple_driver_unregister - unregister a maple driver.
  88  * @drv: maple driver to unregister.
  89  *
  90  * Cleans up after maple_driver_register(). To be invoked in the exit
  91  * path of any module drivers.
  92  */
  93 void maple_driver_unregister(struct maple_driver *drv)
  94 {
  95         driver_unregister(&drv->drv);
  96 }
  97 EXPORT_SYMBOL_GPL(maple_driver_unregister);
  98
  99 /* set hardware registers to enable next round of dma */
 100 static void maplebus_dma_reset(void)
 101 {
 102         ctrl_outl(MAPLE_MAGIC, MAPLE_RESET);
 103         /* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */
 104         ctrl_outl(1, MAPLE_TRIGTYPE);
 105         ctrl_outl(MAPLE_2MBPS | MAPLE_TIMEOUT(50000), MAPLE_SPEED);
 106         ctrl_outl(PHYSADDR(maple_sendbuf), MAPLE_DMAADDR);
 107         ctrl_outl(1, MAPLE_ENABLE);
 108 }
 109
 110 /**
 111  * maple_getcond_callback - setup handling MAPLE_COMMAND_GETCOND
 112  * @dev: device responding
 113  * @callback: handler callback
 114  * @interval: interval in jiffies between callbacks
 115  * @function: the function code for the device
 116  */
 117 void maple_getcond_callback(struct maple_device *dev,
 118                         void (*callback) (struct mapleq *mq),
 119                         unsigned long interval, unsigned long function)
 120 {
 121         dev->callback = callback;
 122         dev->interval = interval;
 123         dev->function = cpu_to_be32(function);
 124         dev->when = jiffies;
 125 }
 126 EXPORT_SYMBOL_GPL(maple_getcond_callback);
 127
 128 static int maple_dma_done(void)
 129 {
 130         return (ctrl_inl(MAPLE_STATE) & 1) == 0;
 131 }
 132
 133 static void maple_release_device(struct device *dev)
 134 {
 135         struct maple_device *mdev;
 136         struct mapleq *mq;
 137         if (!dev)
 138                 return;
 139         mdev = to_maple_dev(dev);
 140         mq = mdev->mq;
 141         if (mq) {
 142                 if (mq->recvbufdcsp)
 143                         kmem_cache_free(maple_queue_cache, mq->recvbufdcsp);
 144                 kfree(mq);
 145                 mq = NULL;
 146         }
 147         kfree(mdev);
 148 }
 149
 150 /**
 151  * maple_add_packet - add a single instruction to the queue
 152  * @mdev: maple device
 153  * @function: function on device being queried
 154  * @command: maple command to add
 155  * @length: length of command string (in 32 bit words)
 156  * @data: remainder of command string
 157  */
 158 int maple_add_packet(struct maple_device *mdev, u32 function, u32 command,
 159         size_t length, void *data)
 160 {
 161         int locking, ret = 0;
 162         void *sendbuf = NULL;
 163
 164         mutex_lock(&maple_wlist_lock);
 165         /* bounce if device already locked */
 166         locking = mutex_is_locked(&mdev->mq->mutex);
 167         if (locking) {
 168                 ret = -EBUSY;
 169                 goto out;
 170         }
 171
 172         mutex_lock(&mdev->mq->mutex);
 173
 174         if (length) {
 175                 sendbuf = kmalloc(length * 4, GFP_KERNEL);
 176                 if (!sendbuf) {
 177                         mutex_unlock(&mdev->mq->mutex);
 178                         ret = -ENOMEM;
 179                         goto out;
 180                 }
 181                 ((__be32 *)sendbuf)[0] = cpu_to_be32(function);
 182         }
 183
 184         mdev->mq->command = command;
 185         mdev->mq->length = length;
 186         if (length > 1)
 187                 memcpy(sendbuf + 4, data, (length - 1) * 4);
 188         mdev->mq->sendbuf = sendbuf;
 189
 190         list_add(&mdev->mq->list, &maple_waitq);
 191 out:
 192         mutex_unlock(&maple_wlist_lock);
 193         return ret;
 194 }
 195 EXPORT_SYMBOL_GPL(maple_add_packet);
 196
 197 /**
 198  * maple_add_packet_sleeps - add a single instruction to the queue
 199  * @mdev: maple device
 200  * @function: function on device being queried
 201  * @command: maple command to add
 202  * @length: length of command string (in 32 bit words)
 203  * @data: remainder of command string
 204  *
 205  * Same as maple_add_packet(), but waits for the lock to become free.
 206  */
 207 int maple_add_packet_sleeps(struct maple_device *mdev, u32 function,
 208         u32 command, size_t length, void *data)
 209 {
 210         int locking, ret = 0;
 211         void *sendbuf = NULL;
 212
 213         locking = mutex_lock_interruptible(&mdev->mq->mutex);
 214         if (locking) {
 215                 ret = -EIO;
 216                 goto out;
 217         }
 218
 219         if (length) {
 220                 sendbuf = kmalloc(length * 4, GFP_KERNEL);
 221                 if (!sendbuf) {
 222                         mutex_unlock(&mdev->mq->mutex);
 223                         ret = -ENOMEM;
 224                         goto out;
 225                 }
 226                 ((__be32 *)sendbuf)[0] = cpu_to_be32(function);
 227         }
 228
 229         mdev->mq->command = command;
 230         mdev->mq->length = length;
 231         if (length > 1)
 232                 memcpy(sendbuf + 4, data, (length - 1) * 4);
 233         mdev->mq->sendbuf = sendbuf;
 234
 235         mutex_lock(&maple_wlist_lock);
 236         list_add(&mdev->mq->list, &maple_waitq);
 237         mutex_unlock(&maple_wlist_lock);
 238 out:
 239         return ret;
 240 }
 241 EXPORT_SYMBOL_GPL(maple_add_packet_sleeps);
 242
 243 static struct mapleq *maple_allocq(struct maple_device *mdev)
 244 {
 245         struct mapleq *mq;
 246
 247         mq = kmalloc(sizeof(*mq), GFP_KERNEL);
 248         if (!mq)
 249                 goto failed_nomem;
 250
 251         mq->dev = mdev;
 252         mq->recvbufdcsp = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
 253         mq->recvbuf = (void *) P2SEGADDR(mq->recvbufdcsp);
 254         if (!mq->recvbuf)
 255                 goto failed_p2;
 256         /*
 257          * most devices do not need the mutex - but
 258          * anything that injects block reads or writes
 259          * will rely on it
 260          */
 261         mutex_init(&mq->mutex);
 262
 263         return mq;
 264
 265 failed_p2:
 266         kfree(mq);
 267 failed_nomem:
 268         return NULL;
 269 }
 270
 271 static struct maple_device *maple_alloc_dev(int port, int unit)
 272 {
 273         struct maple_device *mdev;
 274
 275         mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
 276         if (!mdev)
 277                 return NULL;
 278
 279         mdev->port = port;
 280         mdev->unit = unit;
 281         mdev->mq = maple_allocq(mdev);
 282
 283         if (!mdev->mq) {
 284                 kfree(mdev);
 285                 return NULL;
 286         }
 287         mdev->dev.bus = &maple_bus_type;
 288         mdev->dev.parent = &maple_bus;
 289         return mdev;
 290 }
 291
 292 static void maple_free_dev(struct maple_device *mdev)
 293 {
 294         if (!mdev)
 295                 return;
 296         if (mdev->mq) {
 297                 if (mdev->mq->recvbufdcsp)
 298                         kmem_cache_free(maple_queue_cache,
 299                                 mdev->mq->recvbufdcsp);
 300                 kfree(mdev->mq);
 301         }
 302         kfree(mdev);
 303 }
 304
 305 /* process the command queue into a maple command block
 306  * terminating command has bit 32 of first long set to 0
 307  */
 308 static void maple_build_block(struct mapleq *mq)
 309 {
 310         int port, unit, from, to, len;
 311         unsigned long *lsendbuf = mq->sendbuf;
 312
 313         port = mq->dev->port & 3;
 314         unit = mq->dev->unit;
 315         len = mq->length;
 316         from = port << 6;
 317         to = (port << 6) | (unit > 0 ? (1 << (unit - 1)) & 0x1f : 0x20);
 318
 319         *maple_lastptr &= 0x7fffffff;
 320         maple_lastptr = maple_sendptr;
 321
 322         *maple_sendptr++ = (port << 16) | len | 0x80000000;
 323         *maple_sendptr++ = PHYSADDR(mq->recvbuf);
 324         *maple_sendptr++ =
 325             mq->command | (to << 8) | (from << 16) | (len << 24);
 326         while (len-- > 0)
 327                 *maple_sendptr++ = *lsendbuf++;
 328 }
 329
 330 /* build up command queue */
 331 static void maple_send(void)
 332 {
 333         int i, maple_packets = 0;
 334         struct mapleq *mq, *nmq;
 335
 336         if (!list_empty(&maple_sentq))
 337                 return;
 338         mutex_lock(&maple_wlist_lock);
 339         if (list_empty(&maple_waitq) || !maple_dma_done()) {
 340                 mutex_unlock(&maple_wlist_lock);
 341                 return;
 342         }
 343         mutex_unlock(&maple_wlist_lock);
 344         maple_lastptr = maple_sendbuf;
 345         maple_sendptr = maple_sendbuf;
 346         mutex_lock(&maple_wlist_lock);
 347         list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
 348                 maple_build_block(mq);
 349                 list_move(&mq->list, &maple_sentq);
 350                 if (maple_packets++ > MAPLE_MAXPACKETS)
 351                         break;
 352         }
 353         mutex_unlock(&maple_wlist_lock);
 354         if (maple_packets > 0) {
 355                 for (i = 0; i < (1 << MAPLE_DMA_PAGES); i++)
 356                         dma_cache_sync(0, maple_sendbuf + i * PAGE_SIZE,
 357                                        PAGE_SIZE, DMA_BIDIRECTIONAL);
 358         }
 359 }
 360
 361 /* check if there is a driver registered likely to match this device */
 362 static int check_matching_maple_driver(struct device_driver *driver,
 363                                         void *devptr)
 364 {
 365         struct maple_driver *maple_drv;
 366         struct maple_device *mdev;
 367
 368         mdev = devptr;
 369         maple_drv = to_maple_driver(driver);
 370         if (mdev->devinfo.function & cpu_to_be32(maple_drv->function))
 371                 return 1;
 372         return 0;
 373 }
 374
 375 static void maple_detach_driver(struct maple_device *mdev)
 376 {
 377         if (!mdev)
 378                 return;
 379         device_unregister(&mdev->dev);
 380         mdev = NULL;
 381 }
 382
 383 /* process initial MAPLE_COMMAND_DEVINFO for each device or port */
 384 static void maple_attach_driver(struct maple_device *mdev)
 385 {
 386         char *p, *recvbuf;
 387         unsigned long function;
 388         int matched, retval;
 389
 390         recvbuf = mdev->mq->recvbuf;
 391         /* copy the data as individual elements in
 392         * case of memory optimisation */
 393         memcpy(&mdev->devinfo.function, recvbuf + 4, 4);
 394         memcpy(&mdev->devinfo.function_data[0], recvbuf + 8, 12);
 395         memcpy(&mdev->devinfo.area_code, recvbuf + 20, 1);
 396         memcpy(&mdev->devinfo.connector_direction, recvbuf + 21, 1);
 397         memcpy(&mdev->devinfo.product_name[0], recvbuf + 22, 30);
 398         memcpy(&mdev->devinfo.product_licence[0], recvbuf + 52, 60);
 399         memcpy(&mdev->devinfo.standby_power, recvbuf + 112, 2);
 400         memcpy(&mdev->devinfo.max_power, recvbuf + 114, 2);
 401         memcpy(mdev->product_name, mdev->devinfo.product_name, 30);
 402         mdev->product_name[30] = '\0';
 403         memcpy(mdev->product_licence, mdev->devinfo.product_licence, 60);
 404         mdev->product_licence[60] = '\0';
 405
 406         for (p = mdev->product_name + 29; mdev->product_name <= p; p--)
 407                 if (*p == ' ')
 408                         *p = '\0';
 409                 else
 410                         break;
 411         for (p = mdev->product_licence + 59; mdev->product_licence <= p; p--)
 412                 if (*p == ' ')
 413                         *p = '\0';
 414                 else
 415                         break;
 416
 417         printk(KERN_INFO "Maple device detected: %s\n",
 418                 mdev->product_name);
 419         printk(KERN_INFO "Maple device: %s\n", mdev->product_licence);
 420
 421         function = be32_to_cpu(mdev->devinfo.function);
 422
 423         if (function > 0x200) {
 424                 /* Do this silently - as not a real device */
 425                 function = 0;
 426                 mdev->driver = &maple_dummy_driver;
 427                 sprintf(mdev->dev.bus_id, "%d:0.port", mdev->port);
 428         } else {
 429                 printk(KERN_INFO
 430                         "Maple bus at (%d, %d): Function 0x%lX\n",
 431                         mdev->port, mdev->unit, function);
 432
 433                 matched =
 434                         bus_for_each_drv(&maple_bus_type, NULL, mdev,
 435                                 check_matching_maple_driver);
 436
 437                 if (matched == 0) {
 438                         /* Driver does not exist yet */
 439                         printk(KERN_INFO
 440                                 "No maple driver found.\n");
 441                         mdev->driver = &maple_dummy_driver;
 442                 }
 443                 sprintf(mdev->dev.bus_id, "%d:0%d.%lX", mdev->port,
 444                         mdev->unit, function);
 445         }
 446         mdev->function = function;
 447         mdev->dev.release = &maple_release_device;
 448         retval = device_register(&mdev->dev);
 449         if (retval) {
 450                 printk(KERN_INFO
 451                 "Maple bus: Attempt to register device"
 452                 " (%x, %x) failed.\n",
 453                 mdev->port, mdev->unit);
 454                 maple_free_dev(mdev);
 455                 mdev = NULL;
 456                 return;
 457         }
 458 }
 459
 460 /*
 461  * if device has been registered for the given
 462  * port and unit then return 1 - allows identification
 463  * of which devices need to be attached or detached
 464  */
 465 static int detach_maple_device(struct device *device, void *portptr)
 466 {
 467         struct maple_device_specify *ds;
 468         struct maple_device *mdev;
 469
 470         ds = portptr;
 471         mdev = to_maple_dev(device);
 472         if (mdev->port == ds->port && mdev->unit == ds->unit)
 473                 return 1;
 474         return 0;
 475 }
 476
 477 static int setup_maple_commands(struct device *device, void *ignored)
 478 {
 479         int add;
 480         struct maple_device *maple_dev = to_maple_dev(device);
 481
 482         if ((maple_dev->interval > 0)
 483             && time_after(jiffies, maple_dev->when)) {
 484                 /* bounce if we cannot lock */
 485                 add = maple_add_packet(maple_dev,
 486                         be32_to_cpu(maple_dev->devinfo.function),
 487                         MAPLE_COMMAND_GETCOND, 1, NULL);
 488                 if (!add)
 489                         maple_dev->when = jiffies + maple_dev->interval;
 490         } else {
 491                 if (time_after(jiffies, maple_pnp_time))
 492                         /* This will also bounce */
 493                         maple_add_packet(maple_dev, 0,
 494                                 MAPLE_COMMAND_DEVINFO, 0, NULL);
 495         }
 496         return 0;
 497 }
 498
 499 /* VBLANK bottom half - implemented via workqueue */
 500 static void maple_vblank_handler(struct work_struct *work)
 501 {
 502         if (!list_empty(&maple_sentq) || !maple_dma_done())
 503                 return;
 504
 505         ctrl_outl(0, MAPLE_ENABLE);
 506
 507         bus_for_each_dev(&maple_bus_type, NULL, NULL,
 508                          setup_maple_commands);
 509
 510         if (time_after(jiffies, maple_pnp_time))
 511                 maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
 512
 513         mutex_lock(&maple_wlist_lock);
 514         if (!list_empty(&maple_waitq) && list_empty(&maple_sentq)) {
 515                 mutex_unlock(&maple_wlist_lock);
 516                 maple_send();
 517         } else {
 518                 mutex_unlock(&maple_wlist_lock);
 519         }
 520
 521         maplebus_dma_reset();
 522 }
 523
 524 /* handle devices added via hotplugs - placing them on queue for DEVINFO*/
 525 static void maple_map_subunits(struct maple_device *mdev, int submask)
 526 {
 527         int retval, k, devcheck;
 528         struct maple_device *mdev_add;
 529         struct maple_device_specify ds;
 530
 531         ds.port = mdev->port;
 532         for (k = 0; k < 5; k++) {
 533                 ds.unit = k + 1;
 534                 retval =
 535                     bus_for_each_dev(&maple_bus_type, NULL, &ds,
 536                                      detach_maple_device);
 537                 if (retval) {
 538                         submask = submask >> 1;
 539                         continue;
 540                 }
 541                 devcheck = submask & 0x01;
 542                 if (devcheck) {
 543                         mdev_add = maple_alloc_dev(mdev->port, k + 1);
 544                         if (!mdev_add)
 545                                 return;
 546                         maple_add_packet(mdev_add, 0, MAPLE_COMMAND_DEVINFO,
 547                                 0, NULL);
 548                         /* mark that we are checking sub devices */
 549                         scanning = 1;
 550                 }
 551                 submask = submask >> 1;
 552         }
 553 }
 554
 555 /* mark a device as removed */
 556 static void maple_clean_submap(struct maple_device *mdev)
 557 {
 558         int killbit;
 559
 560         killbit = (mdev->unit > 0 ? (1 << (mdev->unit - 1)) & 0x1f : 0x20);
 561         killbit = ~killbit;
 562         killbit &= 0xFF;
 563         subdevice_map[mdev->port] = subdevice_map[mdev->port] & killbit;
 564 }
 565
 566 /* handle empty port or hotplug removal */
 567 static void maple_response_none(struct maple_device *mdev,
 568                                 struct mapleq *mq)
 569 {
 570         if (mdev->unit != 0) {
 571                 list_del(&mq->list);
 572                 maple_clean_submap(mdev);
 573                 printk(KERN_INFO
 574                        "Maple bus device detaching at (%d, %d)\n",
 575                        mdev->port, mdev->unit);
 576                 maple_detach_driver(mdev);
 577                 return;
 578         }
 579         if (!started || !fullscan) {
 580                 if (checked[mdev->port] == false) {
 581                         checked[mdev->port] = true;
 582                         printk(KERN_INFO "No maple devices attached"
 583                                 " to port %d\n", mdev->port);
 584                 }
 585                 return;
 586         }
 587         maple_clean_submap(mdev);
 588 }
 589
 590 /* preprocess hotplugs or scans */
 591 static void maple_response_devinfo(struct maple_device *mdev,
 592                                    char *recvbuf)
 593 {
 594         char submask;
 595         if (!started || (scanning == 2) || !fullscan) {
 596                 if ((mdev->unit == 0) && (checked[mdev->port] == false)) {
 597                         checked[mdev->port] = true;
 598                         maple_attach_driver(mdev);
 599                 } else {
 600                         if (mdev->unit != 0)
 601                                 maple_attach_driver(mdev);
 602                 }
 603                 return;
 604         }
 605         if (mdev->unit == 0) {
 606                 submask = recvbuf[2] & 0x1F;
 607                 if (submask ^ subdevice_map[mdev->port]) {
 608                         maple_map_subunits(mdev, submask);
 609                         subdevice_map[mdev->port] = submask;
 610                 }
 611         }
 612 }
 613
 614 static void maple_port_rescan(void)
 615 {
 616         int i;
 617         struct maple_device *mdev;
 618
 619         fullscan = 1;
 620         for (i = 0; i < MAPLE_PORTS; i++) {
 621                 if (checked[i] == false) {
 622                         fullscan = 0;
 623                         mdev = baseunits[i];
 624                         /*
 625                          *  test lock in case scan has failed
 626                          *  but device is still locked
 627                          */
 628                         if (mutex_is_locked(&mdev->mq->mutex))
 629                                 mutex_unlock(&mdev->mq->mutex);
 630                         maple_add_packet(mdev, 0, MAPLE_COMMAND_DEVINFO,
 631                                 0, NULL);
 632                 }
 633         }
 634 }
 635
 636 /* maple dma end bottom half - implemented via workqueue */
 637 static void maple_dma_handler(struct work_struct *work)
 638 {
 639         struct mapleq *mq, *nmq;
 640         struct maple_device *dev;
 641         char *recvbuf;
 642         enum maple_code code;
 643
 644         if (!maple_dma_done())
 645                 return;
 646         ctrl_outl(0, MAPLE_ENABLE);
 647         if (!list_empty(&maple_sentq)) {
 648                 list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
 649                         recvbuf = mq->recvbuf;
 650                         code = recvbuf[0];
 651                         dev = mq->dev;
 652                         kfree(mq->sendbuf);
 653                         mutex_unlock(&mq->mutex);
 654                         list_del_init(&mq->list);
 655
 656                         switch (code) {
 657                         case MAPLE_RESPONSE_NONE:
 658                                 maple_response_none(dev, mq);
 659                                 break;
 660
 661                         case MAPLE_RESPONSE_DEVINFO:
 662                                 maple_response_devinfo(dev, recvbuf);
 663                                 break;
 664
 665                         case MAPLE_RESPONSE_DATATRF:
 666                                 if (dev->callback)
 667                                         dev->callback(mq);
 668                                 break;
 669
 670                         case MAPLE_RESPONSE_FILEERR:
 671                         case MAPLE_RESPONSE_AGAIN:
 672                         case MAPLE_RESPONSE_BADCMD:
 673                         case MAPLE_RESPONSE_BADFUNC:
 674                                 printk(KERN_DEBUG
 675                                        "Maple non-fatal error 0x%X\n",
 676                                        code);
 677                                 break;
 678
 679                         case MAPLE_RESPONSE_ALLINFO:
 680                                 printk(KERN_DEBUG
 681                                        "Maple - extended device information"
 682                                         " not supported\n");
 683                                 break;
 684
 685                         case MAPLE_RESPONSE_OK:
 686                                 break;
 687
 688                         default:
 689                                 break;
 690                         }
 691                 }
 692                 /* if scanning is 1 then we have subdevices to check */
 693                 if (scanning == 1) {
 694                         maple_send();
 695                         scanning = 2;
 696                 } else
 697                         scanning = 0;
 698                 /*check if we have actually tested all ports yet */
 699                 if (!fullscan)
 700                         maple_port_rescan();
 701                 /* mark that we have been through the first scan */
 702                 if (started == 0)
 703                         started = 1;
 704         }
 705         maplebus_dma_reset();
 706 }
 707
 708 static irqreturn_t maplebus_dma_interrupt(int irq, void *dev_id)
 709 {
 710         /* Load everything into the bottom half */
 711         schedule_work(&maple_dma_process);
 712         return IRQ_HANDLED;
 713 }
 714
 715 static irqreturn_t maplebus_vblank_interrupt(int irq, void *dev_id)
 716 {
 717         schedule_work(&maple_vblank_process);
 718         return IRQ_HANDLED;
 719 }
 720
 721 static int maple_set_dma_interrupt_handler(void)
 722 {
 723         return request_irq(HW_EVENT_MAPLE_DMA, maplebus_dma_interrupt,
 724                 IRQF_SHARED, "maple bus DMA", &maple_dummy_driver);
 725 }
 726
 727 static int maple_set_vblank_interrupt_handler(void)
 728 {
 729         return request_irq(HW_EVENT_VSYNC, maplebus_vblank_interrupt,
 730                 IRQF_SHARED, "maple bus VBLANK", &maple_dummy_driver);
 731 }
 732
 733 static int maple_get_dma_buffer(void)
 734 {
 735         maple_sendbuf =
 736             (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
 737                                       MAPLE_DMA_PAGES);
 738         if (!maple_sendbuf)
 739                 return -ENOMEM;
 740         return 0;
 741 }
 742
 743 static int match_maple_bus_driver(struct device *devptr,
 744                                   struct device_driver *drvptr)
 745 {
 746         struct maple_driver *maple_drv = to_maple_driver(drvptr);
 747         struct maple_device *maple_dev = to_maple_dev(devptr);
 748
 749         /* Trap empty port case */
 750         if (maple_dev->devinfo.function == 0xFFFFFFFF)
 751                 return 0;
 752         else if (maple_dev->devinfo.function &
 753                  cpu_to_be32(maple_drv->function))
 754                 return 1;
 755         return 0;
 756 }
 757
 758 static int maple_bus_uevent(struct device *dev,
 759                             struct kobj_uevent_env *env)
 760 {
 761         return 0;
 762 }
 763
 764 static void maple_bus_release(struct device *dev)
 765 {
 766 }
 767
 768 static struct maple_driver maple_dummy_driver = {
 769         .drv = {
 770                 .name = "maple_dummy_driver",
 771                 .bus = &maple_bus_type,
 772         },
 773 };
 774
 775 struct bus_type maple_bus_type = {
 776         .name = "maple",
 777         .match = match_maple_bus_driver,
 778         .uevent = maple_bus_uevent,
 779 };
 780 EXPORT_SYMBOL_GPL(maple_bus_type);
 781
 782 static struct device maple_bus = {
 783         .bus_id = "maple",
 784         .release = maple_bus_release,
 785 };
 786
 787 static int __init maple_bus_init(void)
 788 {
 789         int retval, i;
 790         struct maple_device *mdev[MAPLE_PORTS];
 791         ctrl_outl(0, MAPLE_STATE);
 792
 793         retval = device_register(&maple_bus);
 794         if (retval)
 795                 goto cleanup;
 796
 797         retval = bus_register(&maple_bus_type);
 798         if (retval)
 799                 goto cleanup_device;
 800
 801         retval = driver_register(&maple_dummy_driver.drv);
 802         if (retval)
 803                 goto cleanup_bus;
 804
 805         /* allocate memory for maple bus dma */
 806         retval = maple_get_dma_buffer();
 807         if (retval) {
 808                 printk(KERN_INFO
 809                        "Maple bus: Failed to allocate Maple DMA buffers\n");
 810                 goto cleanup_basic;
 811         }
 812
 813         /* set up DMA interrupt handler */
 814         retval = maple_set_dma_interrupt_handler();
 815         if (retval) {
 816                 printk(KERN_INFO
 817                        "Maple bus: Failed to grab maple DMA IRQ\n");
 818                 goto cleanup_dma;
 819         }
 820
 821         /* set up VBLANK interrupt handler */
 822         retval = maple_set_vblank_interrupt_handler();
 823         if (retval) {
 824                 printk(KERN_INFO "Maple bus: Failed to grab VBLANK IRQ\n");
 825                 goto cleanup_irq;
 826         }
 827
 828         maple_queue_cache =
 829             kmem_cache_create("maple_queue_cache", 0x400, 0,
 830                               SLAB_POISON|SLAB_HWCACHE_ALIGN, NULL);
 831
 832         if (!maple_queue_cache)
 833                 goto cleanup_bothirqs;
 834
 835         INIT_LIST_HEAD(&maple_waitq);
 836         INIT_LIST_HEAD(&maple_sentq);
 837
 838         /* setup maple ports */
 839         for (i = 0; i < MAPLE_PORTS; i++) {
 840                 checked[i] = false;
 841                 mdev[i] = maple_alloc_dev(i, 0);
 842                 baseunits[i] = mdev[i];
 843                 if (!mdev[i]) {
 844                         while (i-- > 0)
 845                                 maple_free_dev(mdev[i]);
 846                         goto cleanup_cache;
 847                 }
 848                 maple_add_packet(mdev[i], 0, MAPLE_COMMAND_DEVINFO, 0, NULL);
 849                 subdevice_map[i] = 0;
 850         }
 851
 852         /* setup maplebus hardware */
 853         maplebus_dma_reset();
 854         /* initial detection */
 855         maple_send();
 856         maple_pnp_time = jiffies;
 857         printk(KERN_INFO "Maple bus core now registered.\n");
 858
 859         return 0;
 860
 861 cleanup_cache:
 862         kmem_cache_destroy(maple_queue_cache);
 863
 864 cleanup_bothirqs:
 865         free_irq(HW_EVENT_VSYNC, 0);
 866
 867 cleanup_irq:
 868         free_irq(HW_EVENT_MAPLE_DMA, 0);
 869
 870 cleanup_dma:
 871         free_pages((unsigned long) maple_sendbuf, MAPLE_DMA_PAGES);
 872
 873 cleanup_basic:
 874         driver_unregister(&maple_dummy_driver.drv);
 875
 876 cleanup_bus:
 877         bus_unregister(&maple_bus_type);
 878
 879 cleanup_device:
 880         device_unregister(&maple_bus);
 881
 882 cleanup:
 883         printk(KERN_INFO "Maple bus registration failed\n");
 884         return retval;
 885 }
 886 /* Push init to later to ensure hardware gets detected */
 887 fs_initcall(maple_bus_init);