drivers/mtd/maps/vmu-flash.c

   1 /* vmu-flash.c
   2  * Driver for SEGA Dreamcast Visual Memory Unit
   3  *
   4  * Copyright (c) Adrian McMenamin 2002 - 2009
   5  * Copyright (c) Paul Mundt 2001
   6  *
   7  * Licensed under version 2 of the
   8  * GNU General Public Licence
   9  */
  10 #include <linux/init.h>
  11 #include <linux/slab.h>
  12 #include <linux/sched.h>
  13 #include <linux/delay.h>
  14 #include <linux/maple.h>
  15 #include <linux/mtd/mtd.h>
  16 #include <linux/mtd/map.h>
  17
  18 struct vmu_cache {
  19         unsigned char *buffer;          /* Cache */
  20         unsigned int block;             /* Which block was cached */
  21         unsigned long jiffies_atc;      /* When was it cached? */
  22         int valid;
  23 };
  24
  25 struct mdev_part {
  26         struct maple_device *mdev;
  27         int partition;
  28 };
  29
  30 struct vmupart {
  31         u16 user_blocks;
  32         u16 root_block;
  33         u16 numblocks;
  34         char *name;
  35         struct vmu_cache *pcache;
  36 };
  37
  38 struct memcard {
  39         u16 tempA;
  40         u16 tempB;
  41         u32 partitions;
  42         u32 blocklen;
  43         u32 writecnt;
  44         u32 readcnt;
  45         u32 removeable;
  46         int partition;
  47         int read;
  48         unsigned char *blockread;
  49         struct vmupart *parts;
  50         struct mtd_info *mtd;
  51 };
  52
  53 struct vmu_block {
  54         unsigned int num; /* block number */
  55         unsigned int ofs; /* block offset */
  56 };
  57
  58 static struct vmu_block *ofs_to_block(unsigned long src_ofs,
  59         struct mtd_info *mtd, int partition)
  60 {
  61         struct vmu_block *vblock;
  62         struct maple_device *mdev;
  63         struct memcard *card;
  64         struct mdev_part *mpart;
  65         int num;
  66
  67         mpart = mtd->priv;
  68         mdev = mpart->mdev;
  69         card = maple_get_drvdata(mdev);
  70
  71         if (src_ofs >= card->parts[partition].numblocks * card->blocklen)
  72                 goto failed;
  73
  74         num = src_ofs / card->blocklen;
  75         if (num > card->parts[partition].numblocks)
  76                 goto failed;
  77
  78         vblock = kmalloc(sizeof(struct vmu_block), GFP_KERNEL);
  79         if (!vblock)
  80                 goto failed;
  81
  82         vblock->num = num;
  83         vblock->ofs = src_ofs % card->blocklen;
  84         return vblock;
  85
  86 failed:
  87         return NULL;
  88 }
  89
  90 /* Maple bus callback function for reads */
  91 static void vmu_blockread(struct mapleq *mq)
  92 {
  93         struct maple_device *mdev;
  94         struct memcard *card;
  95
  96         mdev = mq->dev;
  97         card = maple_get_drvdata(mdev);
  98         /* copy the read in data */
  99
 100         if (unlikely(!card->blockread))
 101                 return;
 102
 103         memcpy(card->blockread, mq->recvbuf->buf + 12,
 104                 card->blocklen/card->readcnt);
 105
 106 }
 107
 108 /* Interface with maple bus to read blocks
 109  * caching the results so that other parts
 110  * of the driver can access block reads */
 111 static int maple_vmu_read_block(unsigned int num, unsigned char *buf,
 112         struct mtd_info *mtd)
 113 {
 114         struct memcard *card;
 115         struct mdev_part *mpart;
 116         struct maple_device *mdev;
 117         int partition, error = 0, x, wait;
 118         unsigned char *blockread = NULL;
 119         struct vmu_cache *pcache;
 120         __be32 sendbuf;
 121
 122         mpart = mtd->priv;
 123         mdev = mpart->mdev;
 124         partition = mpart->partition;
 125         card = maple_get_drvdata(mdev);
 126         pcache = card->parts[partition].pcache;
 127         pcache->valid = 0;
 128
 129         /* prepare the cache for this block */
 130         if (!pcache->buffer) {
 131                 pcache->buffer = kmalloc(card->blocklen, GFP_KERNEL);
 132                 if (!pcache->buffer) {
 133                         dev_err(&mdev->dev, "VMU at (%d, %d) - read fails due"
 134                                 " to lack of memory\n", mdev->port,
 135                                 mdev->unit);
 136                         error = -ENOMEM;
 137                         goto outB;
 138                 }
 139         }
 140
 141         /*
 142         * Reads may be phased - again the hardware spec
 143         * supports this - though may not be any devices in
 144         * the wild that implement it, but we will here
 145         */
 146         for (x = 0; x < card->readcnt; x++) {
 147                 sendbuf = cpu_to_be32(partition << 24 | x << 16 | num);
 148
 149                 if (atomic_read(&mdev->busy) == 1) {
 150                         wait_event_interruptible_timeout(mdev->maple_wait,
 151                                 atomic_read(&mdev->busy) == 0, HZ);
 152                         if (atomic_read(&mdev->busy) == 1) {
 153                                 dev_notice(&mdev->dev, "VMU at (%d, %d)"
 154                                         " is busy\n", mdev->port, mdev->unit);
 155                                 error = -EAGAIN;
 156                                 goto outB;
 157                         }
 158                 }
 159
 160                 atomic_set(&mdev->busy, 1);
 161                 blockread = kmalloc(card->blocklen/card->readcnt, GFP_KERNEL);
 162                 if (!blockread) {
 163                         error = -ENOMEM;
 164                         atomic_set(&mdev->busy, 0);
 165                         goto outB;
 166                 }
 167                 card->blockread = blockread;
 168
 169                 maple_getcond_callback(mdev, vmu_blockread, 0,
 170                         MAPLE_FUNC_MEMCARD);
 171                 error = maple_add_packet(mdev, MAPLE_FUNC_MEMCARD,
 172                                 MAPLE_COMMAND_BREAD, 2, &sendbuf);
 173                 /* Very long timeouts seem to be needed when box is stressed */
 174                 wait = wait_event_interruptible_timeout(mdev->maple_wait,
 175                         (atomic_read(&mdev->busy) == 0 ||
 176                         atomic_read(&mdev->busy) == 2), HZ * 3);
 177                 /*
 178                 * MTD layer does not handle hotplugging well
 179                 * so have to return errors when VMU is unplugged
 180                 * in the middle of a read (busy == 2)
 181                 */
 182                 if (error || atomic_read(&mdev->busy) == 2) {
 183                         if (atomic_read(&mdev->busy) == 2)
 184                                 error = -ENXIO;
 185                         atomic_set(&mdev->busy, 0);
 186                         card->blockread = NULL;
 187                         goto outA;
 188                 }
 189                 if (wait == 0 || wait == -ERESTARTSYS) {
 190                         card->blockread = NULL;
 191                         atomic_set(&mdev->busy, 0);
 192                         error = -EIO;
 193                         list_del_init(&(mdev->mq->list));
 194                         kfree(mdev->mq->sendbuf);
 195                         mdev->mq->sendbuf = NULL;
 196                         if (wait == -ERESTARTSYS) {
 197                                 dev_warn(&mdev->dev, "VMU read on (%d, %d)"
 198                                         " interrupted on block 0x%X\n",
 199                                         mdev->port, mdev->unit, num);
 200                         } else
 201                                 dev_notice(&mdev->dev, "VMU read on (%d, %d)"
 202                                         " timed out on block 0x%X\n",
 203                                         mdev->port, mdev->unit, num);
 204                         goto outA;
 205                 }
 206
 207                 memcpy(buf + (card->blocklen/card->readcnt) * x, blockread,
 208                         card->blocklen/card->readcnt);
 209
 210                 memcpy(pcache->buffer + (card->blocklen/card->readcnt) * x,
 211                         card->blockread, card->blocklen/card->readcnt);
 212                 card->blockread = NULL;
 213                 pcache->block = num;
 214                 pcache->jiffies_atc = jiffies;
 215                 pcache->valid = 1;
 216                 kfree(blockread);
 217         }
 218
 219         return error;
 220
 221 outA:
 222         kfree(blockread);
 223 outB:
 224         return error;
 225 }
 226
 227 /* communicate with maple bus for phased writing */
 228 static int maple_vmu_write_block(unsigned int num, const unsigned char *buf,
 229         struct mtd_info *mtd)
 230 {
 231         struct memcard *card;
 232         struct mdev_part *mpart;
 233         struct maple_device *mdev;
 234         int partition, error, locking, x, phaselen, wait;
 235         __be32 *sendbuf;
 236
 237         mpart = mtd->priv;
 238         mdev = mpart->mdev;
 239         partition = mpart->partition;
 240         card = maple_get_drvdata(mdev);
 241
 242         phaselen = card->blocklen/card->writecnt;
 243
 244         sendbuf = kmalloc(phaselen + 4, GFP_KERNEL);
 245         if (!sendbuf) {
 246                 error = -ENOMEM;
 247                 goto fail_nosendbuf;
 248         }
 249         for (x = 0; x < card->writecnt; x++) {
 250                 sendbuf[0] = cpu_to_be32(partition << 24 | x << 16 | num);
 251                 memcpy(&sendbuf[1], buf + phaselen * x, phaselen);
 252                 /* wait until the device is not busy doing something else
 253                 * or 1 second - which ever is longer */
 254                 if (atomic_read(&mdev->busy) == 1) {
 255                         wait_event_interruptible_timeout(mdev->maple_wait,
 256                                 atomic_read(&mdev->busy) == 0, HZ);
 257                         if (atomic_read(&mdev->busy) == 1) {
 258                                 error = -EBUSY;
 259                                 dev_notice(&mdev->dev, "VMU write at (%d, %d)"
 260                                         "failed - device is busy\n",
 261                                         mdev->port, mdev->unit);
 262                                 goto fail_nolock;
 263                         }
 264                 }
 265                 atomic_set(&mdev->busy, 1);
 266
 267                 locking = maple_add_packet(mdev, MAPLE_FUNC_MEMCARD,
 268                         MAPLE_COMMAND_BWRITE, phaselen / 4 + 2, sendbuf);
 269                 wait = wait_event_interruptible_timeout(mdev->maple_wait,
 270                         atomic_read(&mdev->busy) == 0, HZ/10);
 271                 if (locking) {
 272                         error = -EIO;
 273                         atomic_set(&mdev->busy, 0);
 274                         goto fail_nolock;
 275                 }
 276                 if (atomic_read(&mdev->busy) == 2) {
 277                         atomic_set(&mdev->busy, 0);
 278                 } else if (wait == 0 || wait == -ERESTARTSYS) {
 279                         error = -EIO;
 280                         dev_warn(&mdev->dev, "Write at (%d, %d) of block"
 281                                 " 0x%X at phase %d failed: could not"
 282                                 " communicate with VMU", mdev->port,
 283                                 mdev->unit, num, x);
 284                         atomic_set(&mdev->busy, 0);
 285                         kfree(mdev->mq->sendbuf);
 286                         mdev->mq->sendbuf = NULL;
 287                         list_del_init(&(mdev->mq->list));
 288                         goto fail_nolock;
 289                 }
 290         }
 291         kfree(sendbuf);
 292
 293         return card->blocklen;
 294
 295 fail_nolock:
 296         kfree(sendbuf);
 297 fail_nosendbuf:
 298         dev_err(&mdev->dev, "VMU (%d, %d): write failed\n", mdev->port,
 299                 mdev->unit);
 300         return error;
 301 }
 302
 303 /* mtd function to simulate reading byte by byte */
 304 static unsigned char vmu_flash_read_char(unsigned long ofs, int *retval,
 305         struct mtd_info *mtd)
 306 {
 307         struct vmu_block *vblock;
 308         struct memcard *card;
 309         struct mdev_part *mpart;
 310         struct maple_device *mdev;
 311         unsigned char *buf, ret;
 312         int partition, error;
 313
 314         mpart = mtd->priv;
 315         mdev = mpart->mdev;
 316         partition = mpart->partition;
 317         card = maple_get_drvdata(mdev);
 318         *retval =  0;
 319
 320         buf = kmalloc(card->blocklen, GFP_KERNEL);
 321         if (!buf) {
 322                 *retval = 1;
 323                 ret = -ENOMEM;
 324                 goto finish;
 325         }
 326
 327         vblock = ofs_to_block(ofs, mtd, partition);
 328         if (!vblock) {
 329                 *retval = 3;
 330                 ret = -ENOMEM;
 331                 goto out_buf;
 332         }
 333
 334         error = maple_vmu_read_block(vblock->num, buf, mtd);
 335         if (error) {
 336                 ret = error;
 337                 *retval = 2;
 338                 goto out_vblock;
 339         }
 340
 341         ret = buf[vblock->ofs];
 342
 343 out_vblock:
 344         kfree(vblock);
 345 out_buf:
 346         kfree(buf);
 347 finish:
 348         return ret;
 349 }
 350
 351 /* mtd higher order function to read flash */
 352 static int vmu_flash_read(struct mtd_info *mtd, loff_t from, size_t len,
 353         size_t *retlen,  u_char *buf)
 354 {
 355         struct maple_device *mdev;
 356         struct memcard *card;
 357         struct mdev_part *mpart;
 358         struct vmu_cache *pcache;
 359         struct vmu_block *vblock;
 360         int index = 0, retval, partition, leftover, numblocks;
 361         unsigned char cx;
 362
 363         if (len < 1)
 364                 return -EIO;
 365
 366         mpart = mtd->priv;
 367         mdev = mpart->mdev;
 368         partition = mpart->partition;
 369         card = maple_get_drvdata(mdev);
 370
 371         numblocks = card->parts[partition].numblocks;
 372         if (from + len > numblocks * card->blocklen)
 373                 len = numblocks * card->blocklen - from;
 374         if (len == 0)
 375                 return -EIO;
 376         /* Have we cached this bit already? */
 377         pcache = card->parts[partition].pcache;
 378         do {
 379                 vblock =  ofs_to_block(from + index, mtd, partition);
 380                 if (!vblock)
 381                         return -ENOMEM;
 382                 /* Have we cached this and is the cache valid and timely? */
 383                 if (pcache->valid &&
 384                         time_before(jiffies, pcache->jiffies_atc + HZ) &&
 385                         (pcache->block == vblock->num)) {
 386                         /* we have cached it, so do necessary copying */
 387                         leftover = card->blocklen - vblock->ofs;
 388                         if (vblock->ofs + len - index < card->blocklen) {
 389                                 /* only a bit of this block to copy */
 390                                 memcpy(buf + index,
 391                                         pcache->buffer + vblock->ofs,
 392                                         len - index);
 393                                 index = len;
 394                         } else {
 395                                 /* otherwise copy remainder of whole block */
 396                                 memcpy(buf + index, pcache->buffer +
 397                                         vblock->ofs, leftover);
 398                                 index += leftover;
 399                         }
 400                 } else {
 401                         /*
 402                         * Not cached so read one byte -
 403                         * but cache the rest of the block
 404                         */
 405                         cx = vmu_flash_read_char(from + index, &retval, mtd);
 406                         if (retval) {
 407                                 *retlen = index;
 408                                 kfree(vblock);
 409                                 return cx;
 410                         }
 411                         memset(buf + index, cx, 1);
 412                         index++;
 413                 }
 414                 kfree(vblock);
 415         } while (len > index);
 416         *retlen = index;
 417
 418         return 0;
 419 }
 420
 421 static int vmu_flash_write(struct mtd_info *mtd, loff_t to, size_t len,
 422         size_t *retlen, const u_char *buf)
 423 {
 424         struct maple_device *mdev;
 425         struct memcard *card;
 426         struct mdev_part *mpart;
 427         int index = 0, partition, error = 0, numblocks;
 428         struct vmu_cache *pcache;
 429         struct vmu_block *vblock;
 430         unsigned char *buffer;
 431
 432         mpart = mtd->priv;
 433         mdev = mpart->mdev;
 434         partition = mpart->partition;
 435         card = maple_get_drvdata(mdev);
 436
 437         /* simple sanity checks */
 438         if (len < 1) {
 439                 error = -EIO;
 440                 goto failed;
 441         }
 442         numblocks = card->parts[partition].numblocks;
 443         if (to + len > numblocks * card->blocklen)
 444                 len = numblocks * card->blocklen - to;
 445         if (len == 0) {
 446                 error = -EIO;
 447                 goto failed;
 448         }
 449
 450         vblock = ofs_to_block(to, mtd, partition);
 451         if (!vblock) {
 452                 error = -ENOMEM;
 453                 goto failed;
 454         }
 455
 456         buffer = kmalloc(card->blocklen, GFP_KERNEL);
 457         if (!buffer) {
 458                 error = -ENOMEM;
 459                 goto fail_buffer;
 460         }
 461
 462         do {
 463                 /* Read in the block we are to write to */
 464                 error = maple_vmu_read_block(vblock->num, buffer, mtd);
 465                 if (error)
 466                         goto fail_io;
 467
 468                 do {
 469                         buffer[vblock->ofs] = buf[index];
 470                         vblock->ofs++;
 471                         index++;
 472                         if (index >= len)
 473                                 break;
 474                 } while (vblock->ofs < card->blocklen);
 475
 476                 /* write out new buffer */
 477                 error = maple_vmu_write_block(vblock->num, buffer, mtd);
 478                 /* invalidate the cache */
 479                 pcache = card->parts[partition].pcache;
 480                 pcache->valid = 0;
 481
 482                 if (error != card->blocklen)
 483                         goto fail_io;
 484
 485                 vblock->num++;
 486                 vblock->ofs = 0;
 487         } while (len > index);
 488
 489         kfree(buffer);
 490         *retlen = index;
 491         kfree(vblock);
 492         return 0;
 493
 494 fail_io:
 495         kfree(buffer);
 496 fail_buffer:
 497         kfree(vblock);
 498 failed:
 499         dev_err(&mdev->dev, "VMU write failing with error %d\n", error);
 500         return error;
 501 }
 502
 503 static void vmu_flash_sync(struct mtd_info *mtd)
 504 {
 505         /* Do nothing here */
 506 }
 507
 508 /* Maple bus callback function to recursively query hardware details */
 509 static void vmu_queryblocks(struct mapleq *mq)
 510 {
 511         struct maple_device *mdev;
 512         unsigned short *res;
 513         struct memcard *card;
 514         __be32 partnum;
 515         struct vmu_cache *pcache;
 516         struct mdev_part *mpart;
 517         struct mtd_info *mtd_cur;
 518         struct vmupart *part_cur;
 519         int error;
 520
 521         mdev = mq->dev;
 522         card = maple_get_drvdata(mdev);
 523         res = (unsigned short *) (mq->recvbuf->buf);
 524         card->tempA = res[12];
 525         card->tempB = res[6];
 526
 527         dev_info(&mdev->dev, "VMU device at partition %d has %d user "
 528                 "blocks with a root block at %d\n", card->partition,
 529                 card->tempA, card->tempB);
 530
 531         part_cur = &card->parts[card->partition];
 532         part_cur->user_blocks = card->tempA;
 533         part_cur->root_block = card->tempB;
 534         part_cur->numblocks = card->tempB + 1;
 535         part_cur->name = kmalloc(12, GFP_KERNEL);
 536         if (!part_cur->name)
 537                 goto fail_name;
 538
 539         sprintf(part_cur->name, "vmu%d.%d.%d",
 540                 mdev->port, mdev->unit, card->partition);
 541         mtd_cur = &card->mtd[card->partition];
 542         mtd_cur->name = part_cur->name;
 543         mtd_cur->type = 8;
 544         mtd_cur->flags = MTD_WRITEABLE|MTD_NO_ERASE;
 545         mtd_cur->size = part_cur->numblocks * card->blocklen;
 546         mtd_cur->erasesize = card->blocklen;
 547         mtd_cur->write = vmu_flash_write;
 548         mtd_cur->read = vmu_flash_read;
 549         mtd_cur->sync = vmu_flash_sync;
 550         mtd_cur->writesize = card->blocklen;
 551
 552         mpart = kmalloc(sizeof(struct mdev_part), GFP_KERNEL);
 553         if (!mpart)
 554                 goto fail_mpart;
 555
 556         mpart->mdev = mdev;
 557         mpart->partition = card->partition;
 558         mtd_cur->priv = mpart;
 559         mtd_cur->owner = THIS_MODULE;
 560
 561         pcache = kzalloc(sizeof(struct vmu_cache), GFP_KERNEL);
 562         if (!pcache)
 563                 goto fail_cache_create;
 564         part_cur->pcache = pcache;
 565
 566         error = add_mtd_device(mtd_cur);
 567         if (error)
 568                 goto fail_mtd_register;
 569
 570         maple_getcond_callback(mdev, NULL, 0,
 571                 MAPLE_FUNC_MEMCARD);
 572
 573         /*
 574         * Set up a recursive call to the (probably theoretical)
 575         * second or more partition
 576         */
 577         if (++card->partition < card->partitions) {
 578                 partnum = cpu_to_be32(card->partition << 24);
 579                 maple_getcond_callback(mdev, vmu_queryblocks, 0,
 580                         MAPLE_FUNC_MEMCARD);
 581                 maple_add_packet(mdev, MAPLE_FUNC_MEMCARD,
 582                         MAPLE_COMMAND_GETMINFO, 2, &partnum);
 583         }
 584         return;
 585
 586 fail_mtd_register:
 587         dev_err(&mdev->dev, "Could not register maple device at (%d, %d)"
 588                 "error is 0x%X\n", mdev->port, mdev->unit, error);
 589         for (error = 0; error <= card->partition; error++) {
 590                 kfree(((card->parts)[error]).pcache);
 591                 ((card->parts)[error]).pcache = NULL;
 592         }
 593 fail_cache_create:
 594 fail_mpart:
 595         for (error = 0; error <= card->partition; error++) {
 596                 kfree(((card->mtd)[error]).priv);
 597                 ((card->mtd)[error]).priv = NULL;
 598         }
 599         maple_getcond_callback(mdev, NULL, 0,
 600                 MAPLE_FUNC_MEMCARD);
 601         kfree(part_cur->name);
 602 fail_name:
 603         return;
 604 }
 605
 606 /* Handles very basic info about the flash, queries for details */
 607 static int __devinit vmu_connect(struct maple_device *mdev)
 608 {
 609         unsigned long test_flash_data, basic_flash_data;
 610         int c, error;
 611         struct memcard *card;
 612         u32 partnum = 0;
 613
 614         test_flash_data = be32_to_cpu(mdev->devinfo.function);
 615         /* Need to count how many bits are set - to find out which
 616          * function_data element has details of the memory card
 617          */
 618         c = hweight_long(test_flash_data);
 619
 620         basic_flash_data = be32_to_cpu(mdev->devinfo.function_data[c - 1]);
 621
 622         card = kmalloc(sizeof(struct memcard), GFP_KERNEL);
 623         if (!card) {
 624                 error = -ENOMEM;
 625                 goto fail_nomem;
 626         }
 627
 628         card->partitions = (basic_flash_data >> 24 & 0xFF) + 1;
 629         card->blocklen = ((basic_flash_data >> 16 & 0xFF) + 1) << 5;
 630         card->writecnt = basic_flash_data >> 12 & 0xF;
 631         card->readcnt = basic_flash_data >> 8 & 0xF;
 632         card->removeable = basic_flash_data >> 7 & 1;
 633
 634         card->partition = 0;
 635
 636         /*
 637         * Not sure there are actually any multi-partition devices in the
 638         * real world, but the hardware supports them, so, so will we
 639         */
 640         card->parts = kmalloc(sizeof(struct vmupart) * card->partitions,
 641                 GFP_KERNEL);
 642         if (!card->parts) {
 643                 error = -ENOMEM;
 644                 goto fail_partitions;
 645         }
 646
 647         card->mtd = kmalloc(sizeof(struct mtd_info) * card->partitions,
 648                 GFP_KERNEL);
 649         if (!card->mtd) {
 650                 error = -ENOMEM;
 651                 goto fail_mtd_info;
 652         }
 653
 654         maple_set_drvdata(mdev, card);
 655
 656         /*
 657         * We want to trap meminfo not get cond
 658         * so set interval to zero, but rely on maple bus
 659         * driver to pass back the results of the meminfo
 660         */
 661         maple_getcond_callback(mdev, vmu_queryblocks, 0,
 662                 MAPLE_FUNC_MEMCARD);
 663
 664         /* Make sure we are clear to go */
 665         if (atomic_read(&mdev->busy) == 1) {
 666                 wait_event_interruptible_timeout(mdev->maple_wait,
 667                         atomic_read(&mdev->busy) == 0, HZ);
 668                 if (atomic_read(&mdev->busy) == 1) {
 669                         dev_notice(&mdev->dev, "VMU at (%d, %d) is busy\n",
 670                                 mdev->port, mdev->unit);
 671                         error = -EAGAIN;
 672                         goto fail_device_busy;
 673                 }
 674         }
 675
 676         atomic_set(&mdev->busy, 1);
 677
 678         /*
 679         * Set up the minfo call: vmu_queryblocks will handle
 680         * the information passed back
 681         */
 682         error = maple_add_packet(mdev, MAPLE_FUNC_MEMCARD,
 683                 MAPLE_COMMAND_GETMINFO, 2, &partnum);
 684         if (error) {
 685                 dev_err(&mdev->dev, "Could not lock VMU at (%d, %d)"
 686                         " error is 0x%X\n", mdev->port, mdev->unit, error);
 687                 goto fail_mtd_info;
 688         }
 689         return 0;
 690
 691 fail_device_busy:
 692         kfree(card->mtd);
 693 fail_mtd_info:
 694         kfree(card->parts);
 695 fail_partitions:
 696         kfree(card);
 697 fail_nomem:
 698         return error;
 699 }
 700
 701 static void __devexit vmu_disconnect(struct maple_device *mdev)
 702 {
 703         struct memcard *card;
 704         struct mdev_part *mpart;
 705         int x;
 706
 707         mdev->callback = NULL;
 708         card = maple_get_drvdata(mdev);
 709         for (x = 0; x < card->partitions; x++) {
 710                 mpart = ((card->mtd)[x]).priv;
 711                 mpart->mdev = NULL;
 712                 del_mtd_device(&((card->mtd)[x]));
 713                 kfree(((card->parts)[x]).name);
 714         }
 715         kfree(card->parts);
 716         kfree(card->mtd);
 717         kfree(card);
 718 }
 719
 720 /* Callback to handle eccentricities of both mtd subsystem
 721  * and general flakyness of Dreamcast VMUs
 722  */
 723 static int vmu_can_unload(struct maple_device *mdev)
 724 {
 725         struct memcard *card;
 726         int x;
 727         struct mtd_info *mtd;
 728
 729         card = maple_get_drvdata(mdev);
 730         for (x = 0; x < card->partitions; x++) {
 731                 mtd = &((card->mtd)[x]);
 732                 if (mtd->usecount > 0)
 733                         return 0;
 734         }
 735         return 1;
 736 }
 737
 738 #define ERRSTR "VMU at (%d, %d) file error -"
 739
 740 static void vmu_file_error(struct maple_device *mdev, void *recvbuf)
 741 {
 742         enum maple_file_errors error = ((int *)recvbuf)[1];
 743
 744         switch (error) {
 745
 746         case MAPLE_FILEERR_INVALID_PARTITION:
 747                 dev_notice(&mdev->dev, ERRSTR " invalid partition number\n",
 748                         mdev->port, mdev->unit);
 749                 break;
 750
 751         case MAPLE_FILEERR_PHASE_ERROR:
 752                 dev_notice(&mdev->dev, ERRSTR " phase error\n",
 753                         mdev->port, mdev->unit);
 754                 break;
 755
 756         case MAPLE_FILEERR_INVALID_BLOCK:
 757                 dev_notice(&mdev->dev, ERRSTR " invalid block number\n",
 758                         mdev->port, mdev->unit);
 759                 break;
 760
 761         case MAPLE_FILEERR_WRITE_ERROR:
 762                 dev_notice(&mdev->dev, ERRSTR " write error\n",
 763                         mdev->port, mdev->unit);
 764                 break;
 765
 766         case MAPLE_FILEERR_INVALID_WRITE_LENGTH:
 767                 dev_notice(&mdev->dev, ERRSTR " invalid write length\n",
 768                         mdev->port, mdev->unit);
 769                 break;
 770
 771         case MAPLE_FILEERR_BAD_CRC:
 772                 dev_notice(&mdev->dev, ERRSTR " bad CRC\n",
 773                         mdev->port, mdev->unit);
 774                 break;
 775
 776         default:
 777                 dev_notice(&mdev->dev, ERRSTR " 0x%X\n",
 778                         mdev->port, mdev->unit, error);
 779         }
 780 }
 781
 782
 783 static int __devinit probe_maple_vmu(struct device *dev)
 784 {
 785         int error;
 786         struct maple_device *mdev = to_maple_dev(dev);
 787         struct maple_driver *mdrv = to_maple_driver(dev->driver);
 788
 789         mdev->can_unload = vmu_can_unload;
 790         mdev->fileerr_handler = vmu_file_error;
 791         mdev->driver = mdrv;
 792
 793         error = vmu_connect(mdev);
 794         if (error)
 795                 return error;
 796
 797         return 0;
 798 }
 799
 800 static int __devexit remove_maple_vmu(struct device *dev)
 801 {
 802         struct maple_device *mdev = to_maple_dev(dev);
 803
 804         vmu_disconnect(mdev);
 805         return 0;
 806 }
 807
 808 static struct maple_driver vmu_flash_driver = {
 809         .function =     MAPLE_FUNC_MEMCARD,
 810         .drv = {
 811                 .name =         "Dreamcast_visual_memory",
 812                 .probe =        probe_maple_vmu,
 813                 .remove =       __devexit_p(remove_maple_vmu),
 814         },
 815 };
 816
 817 static int __init vmu_flash_map_init(void)
 818 {
 819         return maple_driver_register(&vmu_flash_driver);
 820 }
 821
 822 static void __exit vmu_flash_map_exit(void)
 823 {
 824         maple_driver_unregister(&vmu_flash_driver);
 825 }
 826
 827 module_init(vmu_flash_map_init);
 828 module_exit(vmu_flash_map_exit);
 829
 830 MODULE_LICENSE("GPL");
 831 MODULE_AUTHOR("Adrian McMenamin");
 832 MODULE_DESCRIPTION("Flash mapping for Sega Dreamcast visual memory");