drivers/dma/edma.c

   1 /*
   2  * TI EDMA DMA engine driver
   3  *
   4  * Copyright 2012 Texas Instruments
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation version 2.
   9  *
  10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  11  * kind, whether express or implied; without even the implied warranty
  12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/dmaengine.h>
  17 #include <linux/dma-mapping.h>
  18 #include <linux/err.h>
  19 #include <linux/init.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/list.h>
  22 #include <linux/module.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/slab.h>
  25 #include <linux/spinlock.h>
  26
  27 #include <mach/edma.h>
  28
  29 #include "dmaengine.h"
  30 #include "virt-dma.h"
  31
  32 /*
  33  * This will go away when the private EDMA API is folded
  34  * into this driver and the platform device(s) are
  35  * instantiated in the arch code. We can only get away
  36  * with this simplification because DA8XX may not be built
  37  * in the same kernel image with other DaVinci parts. This
  38  * avoids having to sprinkle dmaengine driver platform devices
  39  * and data throughout all the existing board files.
  40  */
  41 #ifdef CONFIG_ARCH_DAVINCI_DA8XX
  42 #define EDMA_CTLRS      2
  43 #define EDMA_CHANS      32
  44 #else
  45 #define EDMA_CTLRS      1
  46 #define EDMA_CHANS      64
  47 #endif /* CONFIG_ARCH_DAVINCI_DA8XX */
  48
  49 /* Max of 16 segments per channel to conserve PaRAM slots */
  50 #define MAX_NR_SG               16
  51 #define EDMA_MAX_SLOTS          MAX_NR_SG
  52 #define EDMA_DESCRIPTORS        16
  53
  54 struct edma_desc {
  55         struct virt_dma_desc            vdesc;
  56         struct list_head                node;
  57         int                             absync;
  58         int                             pset_nr;
  59         struct edmacc_param             pset[0];
  60 };
  61
  62 struct edma_cc;
  63
  64 struct edma_chan {
  65         struct virt_dma_chan            vchan;
  66         struct list_head                node;
  67         struct edma_desc                *edesc;
  68         struct edma_cc                  *ecc;
  69         int                             ch_num;
  70         bool                            alloced;
  71         int                             slot[EDMA_MAX_SLOTS];
  72         struct dma_slave_config         cfg;
  73 };
  74
  75 struct edma_cc {
  76         int                             ctlr;
  77         struct dma_device               dma_slave;
  78         struct edma_chan                slave_chans[EDMA_CHANS];
  79         int                             num_slave_chans;
  80         int                             dummy_slot;
  81 };
  82
  83 static inline struct edma_cc *to_edma_cc(struct dma_device *d)
  84 {
  85         return container_of(d, struct edma_cc, dma_slave);
  86 }
  87
  88 static inline struct edma_chan *to_edma_chan(struct dma_chan *c)
  89 {
  90         return container_of(c, struct edma_chan, vchan.chan);
  91 }
  92
  93 static inline struct edma_desc
  94 *to_edma_desc(struct dma_async_tx_descriptor *tx)
  95 {
  96         return container_of(tx, struct edma_desc, vdesc.tx);
  97 }
  98
  99 static void edma_desc_free(struct virt_dma_desc *vdesc)
 100 {
 101         kfree(container_of(vdesc, struct edma_desc, vdesc));
 102 }
 103
 104 /* Dispatch a queued descriptor to the controller (caller holds lock) */
 105 static void edma_execute(struct edma_chan *echan)
 106 {
 107         struct virt_dma_desc *vdesc = vchan_next_desc(&echan->vchan);
 108         struct edma_desc *edesc;
 109         int i;
 110
 111         if (!vdesc) {
 112                 echan->edesc = NULL;
 113                 return;
 114         }
 115
 116         list_del(&vdesc->node);
 117
 118         echan->edesc = edesc = to_edma_desc(&vdesc->tx);
 119
 120         /* Write descriptor PaRAM set(s) */
 121         for (i = 0; i < edesc->pset_nr; i++) {
 122                 edma_write_slot(echan->slot[i], &edesc->pset[i]);
 123                 dev_dbg(echan->vchan.chan.device->dev,
 124                         "\n pset[%d]:\n"
 125                         "  chnum\t%d\n"
 126                         "  slot\t%d\n"
 127                         "  opt\t%08x\n"
 128                         "  src\t%08x\n"
 129                         "  dst\t%08x\n"
 130                         "  abcnt\t%08x\n"
 131                         "  ccnt\t%08x\n"
 132                         "  bidx\t%08x\n"
 133                         "  cidx\t%08x\n"
 134                         "  lkrld\t%08x\n",
 135                         i, echan->ch_num, echan->slot[i],
 136                         edesc->pset[i].opt,
 137                         edesc->pset[i].src,
 138                         edesc->pset[i].dst,
 139                         edesc->pset[i].a_b_cnt,
 140                         edesc->pset[i].ccnt,
 141                         edesc->pset[i].src_dst_bidx,
 142                         edesc->pset[i].src_dst_cidx,
 143                         edesc->pset[i].link_bcntrld);
 144                 /* Link to the previous slot if not the last set */
 145                 if (i != (edesc->pset_nr - 1))
 146                         edma_link(echan->slot[i], echan->slot[i+1]);
 147                 /* Final pset links to the dummy pset */
 148                 else
 149                         edma_link(echan->slot[i], echan->ecc->dummy_slot);
 150         }
 151
 152         edma_start(echan->ch_num);
 153 }
 154
 155 static int edma_terminate_all(struct edma_chan *echan)
 156 {
 157         unsigned long flags;
 158         LIST_HEAD(head);
 159
 160         spin_lock_irqsave(&echan->vchan.lock, flags);
 161
 162         /*
 163          * Stop DMA activity: we assume the callback will not be called
 164          * after edma_dma() returns (even if it does, it will see
 165          * echan->edesc is NULL and exit.)
 166          */
 167         if (echan->edesc) {
 168                 echan->edesc = NULL;
 169                 edma_stop(echan->ch_num);
 170         }
 171
 172         vchan_get_all_descriptors(&echan->vchan, &head);
 173         spin_unlock_irqrestore(&echan->vchan.lock, flags);
 174         vchan_dma_desc_free_list(&echan->vchan, &head);
 175
 176         return 0;
 177 }
 178
 179 static int edma_slave_config(struct edma_chan *echan,
 180         struct dma_slave_config *cfg)
 181 {
 182         if (cfg->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
 183             cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
 184                 return -EINVAL;
 185
 186         memcpy(&echan->cfg, cfg, sizeof(echan->cfg));
 187
 188         return 0;
 189 }
 190
 191 static int edma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
 192                         unsigned long arg)
 193 {
 194         int ret = 0;
 195         struct dma_slave_config *config;
 196         struct edma_chan *echan = to_edma_chan(chan);
 197
 198         switch (cmd) {
 199         case DMA_TERMINATE_ALL:
 200                 edma_terminate_all(echan);
 201                 break;
 202         case DMA_SLAVE_CONFIG:
 203                 config = (struct dma_slave_config *)arg;
 204                 ret = edma_slave_config(echan, config);
 205                 break;
 206         default:
 207                 ret = -ENOSYS;
 208         }
 209
 210         return ret;
 211 }
 212
 213 static struct dma_async_tx_descriptor *edma_prep_slave_sg(
 214         struct dma_chan *chan, struct scatterlist *sgl,
 215         unsigned int sg_len, enum dma_transfer_direction direction,
 216         unsigned long tx_flags, void *context)
 217 {
 218         struct edma_chan *echan = to_edma_chan(chan);
 219         struct device *dev = chan->device->dev;
 220         struct edma_desc *edesc;
 221         dma_addr_t dev_addr;
 222         enum dma_slave_buswidth dev_width;
 223         u32 burst;
 224         struct scatterlist *sg;
 225         int i;
 226         int acnt, bcnt, ccnt, src, dst, cidx;
 227         int src_bidx, dst_bidx, src_cidx, dst_cidx;
 228
 229         if (unlikely(!echan || !sgl || !sg_len))
 230                 return NULL;
 231
 232         if (direction == DMA_DEV_TO_MEM) {
 233                 dev_addr = echan->cfg.src_addr;
 234                 dev_width = echan->cfg.src_addr_width;
 235                 burst = echan->cfg.src_maxburst;
 236         } else if (direction == DMA_MEM_TO_DEV) {
 237                 dev_addr = echan->cfg.dst_addr;
 238                 dev_width = echan->cfg.dst_addr_width;
 239                 burst = echan->cfg.dst_maxburst;
 240         } else {
 241                 dev_err(dev, "%s: bad direction?\n", __func__);
 242                 return NULL;
 243         }
 244
 245         if (dev_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) {
 246                 dev_err(dev, "Undefined slave buswidth\n");
 247                 return NULL;
 248         }
 249
 250         if (sg_len > MAX_NR_SG) {
 251                 dev_err(dev, "Exceeded max SG segments %d > %d\n",
 252                         sg_len, MAX_NR_SG);
 253                 return NULL;
 254         }
 255
 256         edesc = kzalloc(sizeof(*edesc) + sg_len *
 257                 sizeof(edesc->pset[0]), GFP_ATOMIC);
 258         if (!edesc) {
 259                 dev_dbg(dev, "Failed to allocate a descriptor\n");
 260                 return NULL;
 261         }
 262
 263         edesc->pset_nr = sg_len;
 264
 265         for_each_sg(sgl, sg, sg_len, i) {
 266                 /* Allocate a PaRAM slot, if needed */
 267                 if (echan->slot[i] < 0) {
 268                         echan->slot[i] =
 269                                 edma_alloc_slot(EDMA_CTLR(echan->ch_num),
 270                                                 EDMA_SLOT_ANY);
 271                         if (echan->slot[i] < 0) {
 272                                 dev_err(dev, "Failed to allocate slot\n");
 273                                 return NULL;
 274                         }
 275                 }
 276
 277                 acnt = dev_width;
 278
 279                 /*
 280                  * If the maxburst is equal to the fifo width, use
 281                  * A-synced transfers. This allows for large contiguous
 282                  * buffer transfers using only one PaRAM set.
 283                  */
 284                 if (burst == 1) {
 285                         edesc->absync = false;
 286                         ccnt = sg_dma_len(sg) / acnt / (SZ_64K - 1);
 287                         bcnt = sg_dma_len(sg) / acnt - ccnt * (SZ_64K - 1);
 288                         if (bcnt)
 289                                 ccnt++;
 290                         else
 291                                 bcnt = SZ_64K - 1;
 292                         cidx = acnt;
 293                 /*
 294                  * If maxburst is greater than the fifo address_width,
 295                  * use AB-synced transfers where A count is the fifo
 296                  * address_width and B count is the maxburst. In this
 297                  * case, we are limited to transfers of C count frames
 298                  * of (address_width * maxburst) where C count is limited
 299                  * to SZ_64K-1. This places an upper bound on the length
 300                  * of an SG segment that can be handled.
 301                  */
 302                 } else {
 303                         edesc->absync = true;
 304                         bcnt = burst;
 305                         ccnt = sg_dma_len(sg) / (acnt * bcnt);
 306                         if (ccnt > (SZ_64K - 1)) {
 307                                 dev_err(dev, "Exceeded max SG segment size\n");
 308                                 return NULL;
 309                         }
 310                         cidx = acnt * bcnt;
 311                 }
 312
 313                 if (direction == DMA_MEM_TO_DEV) {
 314                         src = sg_dma_address(sg);
 315                         dst = dev_addr;
 316                         src_bidx = acnt;
 317                         src_cidx = cidx;
 318                         dst_bidx = 0;
 319                         dst_cidx = 0;
 320                 } else {
 321                         src = dev_addr;
 322                         dst = sg_dma_address(sg);
 323                         src_bidx = 0;
 324                         src_cidx = 0;
 325                         dst_bidx = acnt;
 326                         dst_cidx = cidx;
 327                 }
 328
 329                 edesc->pset[i].opt = EDMA_TCC(EDMA_CHAN_SLOT(echan->ch_num));
 330                 /* Configure A or AB synchronized transfers */
 331                 if (edesc->absync)
 332                         edesc->pset[i].opt |= SYNCDIM;
 333                 /* If this is the last set, enable completion interrupt flag */
 334                 if (i == sg_len - 1)
 335                         edesc->pset[i].opt |= TCINTEN;
 336
 337                 edesc->pset[i].src = src;
 338                 edesc->pset[i].dst = dst;
 339
 340                 edesc->pset[i].src_dst_bidx = (dst_bidx << 16) | src_bidx;
 341                 edesc->pset[i].src_dst_cidx = (dst_cidx << 16) | src_cidx;
 342
 343                 edesc->pset[i].a_b_cnt = bcnt << 16 | acnt;
 344                 edesc->pset[i].ccnt = ccnt;
 345                 edesc->pset[i].link_bcntrld = 0xffffffff;
 346
 347         }
 348
 349         return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags);
 350 }
 351
 352 static void edma_callback(unsigned ch_num, u16 ch_status, void *data)
 353 {
 354         struct edma_chan *echan = data;
 355         struct device *dev = echan->vchan.chan.device->dev;
 356         struct edma_desc *edesc;
 357         unsigned long flags;
 358
 359         /* Stop the channel */
 360         edma_stop(echan->ch_num);
 361
 362         switch (ch_status) {
 363         case DMA_COMPLETE:
 364                 dev_dbg(dev, "transfer complete on channel %d\n", ch_num);
 365
 366                 spin_lock_irqsave(&echan->vchan.lock, flags);
 367
 368                 edesc = echan->edesc;
 369                 if (edesc) {
 370                         edma_execute(echan);
 371                         vchan_cookie_complete(&edesc->vdesc);
 372                 }
 373
 374                 spin_unlock_irqrestore(&echan->vchan.lock, flags);
 375
 376                 break;
 377         case DMA_CC_ERROR:
 378                 dev_dbg(dev, "transfer error on channel %d\n", ch_num);
 379                 break;
 380         default:
 381                 break;
 382         }
 383 }
 384
 385 /* Alloc channel resources */
 386 static int edma_alloc_chan_resources(struct dma_chan *chan)
 387 {
 388         struct edma_chan *echan = to_edma_chan(chan);
 389         struct device *dev = chan->device->dev;
 390         int ret;
 391         int a_ch_num;
 392         LIST_HEAD(descs);
 393
 394         a_ch_num = edma_alloc_channel(echan->ch_num, edma_callback,
 395                                         chan, EVENTQ_DEFAULT);
 396
 397         if (a_ch_num < 0) {
 398                 ret = -ENODEV;
 399                 goto err_no_chan;
 400         }
 401
 402         if (a_ch_num != echan->ch_num) {
 403                 dev_err(dev, "failed to allocate requested channel %u:%u\n",
 404                         EDMA_CTLR(echan->ch_num),
 405                         EDMA_CHAN_SLOT(echan->ch_num));
 406                 ret = -ENODEV;
 407                 goto err_wrong_chan;
 408         }
 409
 410         echan->alloced = true;
 411         echan->slot[0] = echan->ch_num;
 412
 413         dev_info(dev, "allocated channel for %u:%u\n",
 414                  EDMA_CTLR(echan->ch_num), EDMA_CHAN_SLOT(echan->ch_num));
 415
 416         return 0;
 417
 418 err_wrong_chan:
 419         edma_free_channel(a_ch_num);
 420 err_no_chan:
 421         return ret;
 422 }
 423
 424 /* Free channel resources */
 425 static void edma_free_chan_resources(struct dma_chan *chan)
 426 {
 427         struct edma_chan *echan = to_edma_chan(chan);
 428         struct device *dev = chan->device->dev;
 429         int i;
 430
 431         /* Terminate transfers */
 432         edma_stop(echan->ch_num);
 433
 434         vchan_free_chan_resources(&echan->vchan);
 435
 436         /* Free EDMA PaRAM slots */
 437         for (i = 1; i < EDMA_MAX_SLOTS; i++) {
 438                 if (echan->slot[i] >= 0) {
 439                         edma_free_slot(echan->slot[i]);
 440                         echan->slot[i] = -1;
 441                 }
 442         }
 443
 444         /* Free EDMA channel */
 445         if (echan->alloced) {
 446                 edma_free_channel(echan->ch_num);
 447                 echan->alloced = false;
 448         }
 449
 450         dev_info(dev, "freeing channel for %u\n", echan->ch_num);
 451 }
 452
 453 /* Send pending descriptor to hardware */
 454 static void edma_issue_pending(struct dma_chan *chan)
 455 {
 456         struct edma_chan *echan = to_edma_chan(chan);
 457         unsigned long flags;
 458
 459         spin_lock_irqsave(&echan->vchan.lock, flags);
 460         if (vchan_issue_pending(&echan->vchan) && !echan->edesc)
 461                 edma_execute(echan);
 462         spin_unlock_irqrestore(&echan->vchan.lock, flags);
 463 }
 464
 465 static size_t edma_desc_size(struct edma_desc *edesc)
 466 {
 467         int i;
 468         size_t size;
 469
 470         if (edesc->absync)
 471                 for (size = i = 0; i < edesc->pset_nr; i++)
 472                         size += (edesc->pset[i].a_b_cnt & 0xffff) *
 473                                 (edesc->pset[i].a_b_cnt >> 16) *
 474                                  edesc->pset[i].ccnt;
 475         else
 476                 size = (edesc->pset[0].a_b_cnt & 0xffff) *
 477                         (edesc->pset[0].a_b_cnt >> 16) +
 478                         (edesc->pset[0].a_b_cnt & 0xffff) *
 479                         (SZ_64K - 1) * edesc->pset[0].ccnt;
 480
 481         return size;
 482 }
 483
 484 /* Check request completion status */
 485 static enum dma_status edma_tx_status(struct dma_chan *chan,
 486                                       dma_cookie_t cookie,
 487                                       struct dma_tx_state *txstate)
 488 {
 489         struct edma_chan *echan = to_edma_chan(chan);
 490         struct virt_dma_desc *vdesc;
 491         enum dma_status ret;
 492         unsigned long flags;
 493
 494         ret = dma_cookie_status(chan, cookie, txstate);
 495         if (ret == DMA_SUCCESS || !txstate)
 496                 return ret;
 497
 498         spin_lock_irqsave(&echan->vchan.lock, flags);
 499         vdesc = vchan_find_desc(&echan->vchan, cookie);
 500         if (vdesc) {
 501                 txstate->residue = edma_desc_size(to_edma_desc(&vdesc->tx));
 502         } else if (echan->edesc && echan->edesc->vdesc.tx.cookie == cookie) {
 503                 struct edma_desc *edesc = echan->edesc;
 504                 txstate->residue = edma_desc_size(edesc);
 505         } else {
 506                 txstate->residue = 0;
 507         }
 508         spin_unlock_irqrestore(&echan->vchan.lock, flags);
 509
 510         return ret;
 511 }
 512
 513 static void __init edma_chan_init(struct edma_cc *ecc,
 514                                   struct dma_device *dma,
 515                                   struct edma_chan *echans)
 516 {
 517         int i, j;
 518
 519         for (i = 0; i < EDMA_CHANS; i++) {
 520                 struct edma_chan *echan = &echans[i];
 521                 echan->ch_num = EDMA_CTLR_CHAN(ecc->ctlr, i);
 522                 echan->ecc = ecc;
 523                 echan->vchan.desc_free = edma_desc_free;
 524
 525                 vchan_init(&echan->vchan, dma);
 526
 527                 INIT_LIST_HEAD(&echan->node);
 528                 for (j = 0; j < EDMA_MAX_SLOTS; j++)
 529                         echan->slot[j] = -1;
 530         }
 531 }
 532
 533 static void edma_dma_init(struct edma_cc *ecc, struct dma_device *dma,
 534                           struct device *dev)
 535 {
 536         dma->device_prep_slave_sg = edma_prep_slave_sg;
 537         dma->device_alloc_chan_resources = edma_alloc_chan_resources;
 538         dma->device_free_chan_resources = edma_free_chan_resources;
 539         dma->device_issue_pending = edma_issue_pending;
 540         dma->device_tx_status = edma_tx_status;
 541         dma->device_control = edma_control;
 542         dma->dev = dev;
 543
 544         INIT_LIST_HEAD(&dma->channels);
 545 }
 546
 547 static int edma_probe(struct platform_device *pdev)
 548 {
 549         struct edma_cc *ecc;
 550         int ret;
 551
 552         ecc = devm_kzalloc(&pdev->dev, sizeof(*ecc), GFP_KERNEL);
 553         if (!ecc) {
 554                 dev_err(&pdev->dev, "Can't allocate controller\n");
 555                 return -ENOMEM;
 556         }
 557
 558         ecc->ctlr = pdev->id;
 559         ecc->dummy_slot = edma_alloc_slot(ecc->ctlr, EDMA_SLOT_ANY);
 560         if (ecc->dummy_slot < 0) {
 561                 dev_err(&pdev->dev, "Can't allocate PaRAM dummy slot\n");
 562                 return -EIO;
 563         }
 564
 565         dma_cap_zero(ecc->dma_slave.cap_mask);
 566         dma_cap_set(DMA_SLAVE, ecc->dma_slave.cap_mask);
 567
 568         edma_dma_init(ecc, &ecc->dma_slave, &pdev->dev);
 569
 570         edma_chan_init(ecc, &ecc->dma_slave, ecc->slave_chans);
 571
 572         ret = dma_async_device_register(&ecc->dma_slave);
 573         if (ret)
 574                 goto err_reg1;
 575
 576         platform_set_drvdata(pdev, ecc);
 577
 578         dev_info(&pdev->dev, "TI EDMA DMA engine driver\n");
 579
 580         return 0;
 581
 582 err_reg1:
 583         edma_free_slot(ecc->dummy_slot);
 584         return ret;
 585 }
 586
 587 static int edma_remove(struct platform_device *pdev)
 588 {
 589         struct device *dev = &pdev->dev;
 590         struct edma_cc *ecc = dev_get_drvdata(dev);
 591
 592         dma_async_device_unregister(&ecc->dma_slave);
 593         edma_free_slot(ecc->dummy_slot);
 594
 595         return 0;
 596 }
 597
 598 static struct platform_driver edma_driver = {
 599         .probe          = edma_probe,
 600         .remove         = edma_remove,
 601         .driver = {
 602                 .name = "edma-dma-engine",
 603                 .owner = THIS_MODULE,
 604         },
 605 };
 606
 607 bool edma_filter_fn(struct dma_chan *chan, void *param)
 608 {
 609         if (chan->device->dev->driver == &edma_driver.driver) {
 610                 struct edma_chan *echan = to_edma_chan(chan);
 611                 unsigned ch_req = *(unsigned *)param;
 612                 return ch_req == echan->ch_num;
 613         }
 614         return false;
 615 }
 616 EXPORT_SYMBOL(edma_filter_fn);
 617
 618 static struct platform_device *pdev0, *pdev1;
 619
 620 static const struct platform_device_info edma_dev_info0 = {
 621         .name = "edma-dma-engine",
 622         .id = 0,
 623 };
 624
 625 static const struct platform_device_info edma_dev_info1 = {
 626         .name = "edma-dma-engine",
 627         .id = 1,
 628 };
 629
 630 static int edma_init(void)
 631 {
 632         int ret = platform_driver_register(&edma_driver);
 633
 634         if (ret == 0) {
 635                 pdev0 = platform_device_register_full(&edma_dev_info0);
 636                 if (IS_ERR(pdev0)) {
 637                         platform_driver_unregister(&edma_driver);
 638                         ret = PTR_ERR(pdev0);
 639                         goto out;
 640                 }
 641                 pdev0->dev.dma_mask = &pdev0->dev.coherent_dma_mask;
 642                 pdev0->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 643         }
 644
 645         if (EDMA_CTLRS == 2) {
 646                 pdev1 = platform_device_register_full(&edma_dev_info1);
 647                 if (IS_ERR(pdev1)) {
 648                         platform_driver_unregister(&edma_driver);
 649                         platform_device_unregister(pdev0);
 650                         ret = PTR_ERR(pdev1);
 651                 }
 652                 pdev1->dev.dma_mask = &pdev1->dev.coherent_dma_mask;
 653                 pdev1->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 654         }
 655
 656 out:
 657         return ret;
 658 }
 659 subsys_initcall(edma_init);
 660
 661 static void __exit edma_exit(void)
 662 {
 663         platform_device_unregister(pdev0);
 664         if (pdev1)
 665                 platform_device_unregister(pdev1);
 666         platform_driver_unregister(&edma_driver);
 667 }
 668 module_exit(edma_exit);
 669
 670 MODULE_AUTHOR("Matt Porter <mporter@ti.com>");
 671 MODULE_DESCRIPTION("TI EDMA DMA engine driver");
 672 MODULE_LICENSE("GPL v2");