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