drivers/dma/idma64.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Core driver for the Intel integrated DMA 64-bit
   4  *
   5  * Copyright (C) 2015 Intel Corporation
   6  * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
   7  */
   8
   9 #include <linux/bitops.h>
  10 #include <linux/delay.h>
  11 #include <linux/dmaengine.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/dmapool.h>
  14 #include <linux/init.h>
  15 #include <linux/module.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/slab.h>
  18
  19 #include <linux/dma/idma64.h>
  20
  21 #include "idma64.h"
  22
  23 /* For now we support only two channels */
  24 #define IDMA64_NR_CHAN          2
  25
  26 /* ---------------------------------------------------------------------- */
  27
  28 static struct device *chan2dev(struct dma_chan *chan)
  29 {
  30         return &chan->dev->device;
  31 }
  32
  33 /* ---------------------------------------------------------------------- */
  34
  35 static void idma64_off(struct idma64 *idma64)
  36 {
  37         unsigned short count = 100;
  38
  39         dma_writel(idma64, CFG, 0);
  40
  41         channel_clear_bit(idma64, MASK(XFER), idma64->all_chan_mask);
  42         channel_clear_bit(idma64, MASK(BLOCK), idma64->all_chan_mask);
  43         channel_clear_bit(idma64, MASK(SRC_TRAN), idma64->all_chan_mask);
  44         channel_clear_bit(idma64, MASK(DST_TRAN), idma64->all_chan_mask);
  45         channel_clear_bit(idma64, MASK(ERROR), idma64->all_chan_mask);
  46
  47         do {
  48                 cpu_relax();
  49         } while (dma_readl(idma64, CFG) & IDMA64_CFG_DMA_EN && --count);
  50 }
  51
  52 static void idma64_on(struct idma64 *idma64)
  53 {
  54         dma_writel(idma64, CFG, IDMA64_CFG_DMA_EN);
  55 }
  56
  57 /* ---------------------------------------------------------------------- */
  58
  59 static void idma64_chan_init(struct idma64 *idma64, struct idma64_chan *idma64c)
  60 {
  61         u32 cfghi = IDMA64C_CFGH_SRC_PER(1) | IDMA64C_CFGH_DST_PER(0);
  62         u32 cfglo = 0;
  63
  64         /* Set default burst alignment */
  65         cfglo |= IDMA64C_CFGL_DST_BURST_ALIGN | IDMA64C_CFGL_SRC_BURST_ALIGN;
  66
  67         channel_writel(idma64c, CFG_LO, cfglo);
  68         channel_writel(idma64c, CFG_HI, cfghi);
  69
  70         /* Enable interrupts */
  71         channel_set_bit(idma64, MASK(XFER), idma64c->mask);
  72         channel_set_bit(idma64, MASK(ERROR), idma64c->mask);
  73
  74         /*
  75          * Enforce the controller to be turned on.
  76          *
  77          * The iDMA is turned off in ->probe() and looses context during system
  78          * suspend / resume cycle. That's why we have to enable it each time we
  79          * use it.
  80          */
  81         idma64_on(idma64);
  82 }
  83
  84 static void idma64_chan_stop(struct idma64 *idma64, struct idma64_chan *idma64c)
  85 {
  86         channel_clear_bit(idma64, CH_EN, idma64c->mask);
  87 }
  88
  89 static void idma64_chan_start(struct idma64 *idma64, struct idma64_chan *idma64c)
  90 {
  91         struct idma64_desc *desc = idma64c->desc;
  92         struct idma64_hw_desc *hw = &desc->hw[0];
  93
  94         channel_writeq(idma64c, SAR, 0);
  95         channel_writeq(idma64c, DAR, 0);
  96
  97         channel_writel(idma64c, CTL_HI, IDMA64C_CTLH_BLOCK_TS(~0UL));
  98         channel_writel(idma64c, CTL_LO, IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
  99
 100         channel_writeq(idma64c, LLP, hw->llp);
 101
 102         channel_set_bit(idma64, CH_EN, idma64c->mask);
 103 }
 104
 105 static void idma64_stop_transfer(struct idma64_chan *idma64c)
 106 {
 107         struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
 108
 109         idma64_chan_stop(idma64, idma64c);
 110 }
 111
 112 static void idma64_start_transfer(struct idma64_chan *idma64c)
 113 {
 114         struct idma64 *idma64 = to_idma64(idma64c->vchan.chan.device);
 115         struct virt_dma_desc *vdesc;
 116
 117         /* Get the next descriptor */
 118         vdesc = vchan_next_desc(&idma64c->vchan);
 119         if (!vdesc) {
 120                 idma64c->desc = NULL;
 121                 return;
 122         }
 123
 124         list_del(&vdesc->node);
 125         idma64c->desc = to_idma64_desc(vdesc);
 126
 127         /* Configure the channel */
 128         idma64_chan_init(idma64, idma64c);
 129
 130         /* Start the channel with a new descriptor */
 131         idma64_chan_start(idma64, idma64c);
 132 }
 133
 134 /* ---------------------------------------------------------------------- */
 135
 136 static void idma64_chan_irq(struct idma64 *idma64, unsigned short c,
 137                 u32 status_err, u32 status_xfer)
 138 {
 139         struct idma64_chan *idma64c = &idma64->chan[c];
 140         struct dma_chan_percpu *stat;
 141         struct idma64_desc *desc;
 142
 143         stat = this_cpu_ptr(idma64c->vchan.chan.local);
 144
 145         spin_lock(&idma64c->vchan.lock);
 146         desc = idma64c->desc;
 147         if (desc) {
 148                 if (status_err & (1 << c)) {
 149                         dma_writel(idma64, CLEAR(ERROR), idma64c->mask);
 150                         desc->status = DMA_ERROR;
 151                 } else if (status_xfer & (1 << c)) {
 152                         dma_writel(idma64, CLEAR(XFER), idma64c->mask);
 153                         desc->status = DMA_COMPLETE;
 154                         vchan_cookie_complete(&desc->vdesc);
 155                         stat->bytes_transferred += desc->length;
 156                         idma64_start_transfer(idma64c);
 157                 }
 158
 159                 /* idma64_start_transfer() updates idma64c->desc */
 160                 if (idma64c->desc == NULL || desc->status == DMA_ERROR)
 161                         idma64_stop_transfer(idma64c);
 162         }
 163         spin_unlock(&idma64c->vchan.lock);
 164 }
 165
 166 static irqreturn_t idma64_irq(int irq, void *dev)
 167 {
 168         struct idma64 *idma64 = dev;
 169         u32 status = dma_readl(idma64, STATUS_INT);
 170         u32 status_xfer;
 171         u32 status_err;
 172         unsigned short i;
 173
 174         dev_vdbg(idma64->dma.dev, "%s: status=%#x\n", __func__, status);
 175
 176         /* Check if we have any interrupt from the DMA controller */
 177         if (!status)
 178                 return IRQ_NONE;
 179
 180         status_xfer = dma_readl(idma64, RAW(XFER));
 181         status_err = dma_readl(idma64, RAW(ERROR));
 182
 183         for (i = 0; i < idma64->dma.chancnt; i++)
 184                 idma64_chan_irq(idma64, i, status_err, status_xfer);
 185
 186         return IRQ_HANDLED;
 187 }
 188
 189 /* ---------------------------------------------------------------------- */
 190
 191 static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc)
 192 {
 193         struct idma64_desc *desc;
 194
 195         desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
 196         if (!desc)
 197                 return NULL;
 198
 199         desc->hw = kcalloc(ndesc, sizeof(*desc->hw), GFP_NOWAIT);
 200         if (!desc->hw) {
 201                 kfree(desc);
 202                 return NULL;
 203         }
 204
 205         return desc;
 206 }
 207
 208 static void idma64_desc_free(struct idma64_chan *idma64c,
 209                 struct idma64_desc *desc)
 210 {
 211         struct idma64_hw_desc *hw;
 212
 213         if (desc->ndesc) {
 214                 unsigned int i = desc->ndesc;
 215
 216                 do {
 217                         hw = &desc->hw[--i];
 218                         dma_pool_free(idma64c->pool, hw->lli, hw->llp);
 219                 } while (i);
 220         }
 221
 222         kfree(desc->hw);
 223         kfree(desc);
 224 }
 225
 226 static void idma64_vdesc_free(struct virt_dma_desc *vdesc)
 227 {
 228         struct idma64_chan *idma64c = to_idma64_chan(vdesc->tx.chan);
 229
 230         idma64_desc_free(idma64c, to_idma64_desc(vdesc));
 231 }
 232
 233 static void idma64_hw_desc_fill(struct idma64_hw_desc *hw,
 234                 struct dma_slave_config *config,
 235                 enum dma_transfer_direction direction, u64 llp)
 236 {
 237         struct idma64_lli *lli = hw->lli;
 238         u64 sar, dar;
 239         u32 ctlhi = IDMA64C_CTLH_BLOCK_TS(hw->len);
 240         u32 ctllo = IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN;
 241         u32 src_width, dst_width;
 242
 243         if (direction == DMA_MEM_TO_DEV) {
 244                 sar = hw->phys;
 245                 dar = config->dst_addr;
 246                 ctllo |= IDMA64C_CTLL_DST_FIX | IDMA64C_CTLL_SRC_INC |
 247                          IDMA64C_CTLL_FC_M2P;
 248                 src_width = __ffs(sar | hw->len | 4);
 249                 dst_width = __ffs(config->dst_addr_width);
 250         } else {        /* DMA_DEV_TO_MEM */
 251                 sar = config->src_addr;
 252                 dar = hw->phys;
 253                 ctllo |= IDMA64C_CTLL_DST_INC | IDMA64C_CTLL_SRC_FIX |
 254                          IDMA64C_CTLL_FC_P2M;
 255                 src_width = __ffs(config->src_addr_width);
 256                 dst_width = __ffs(dar | hw->len | 4);
 257         }
 258
 259         lli->sar = sar;
 260         lli->dar = dar;
 261
 262         lli->ctlhi = ctlhi;
 263         lli->ctllo = ctllo |
 264                      IDMA64C_CTLL_SRC_MSIZE(config->src_maxburst) |
 265                      IDMA64C_CTLL_DST_MSIZE(config->dst_maxburst) |
 266                      IDMA64C_CTLL_DST_WIDTH(dst_width) |
 267                      IDMA64C_CTLL_SRC_WIDTH(src_width);
 268
 269         lli->llp = llp;
 270 }
 271
 272 static void idma64_desc_fill(struct idma64_chan *idma64c,
 273                 struct idma64_desc *desc)
 274 {
 275         struct dma_slave_config *config = &idma64c->config;
 276         unsigned int i = desc->ndesc;
 277         struct idma64_hw_desc *hw = &desc->hw[i - 1];
 278         struct idma64_lli *lli = hw->lli;
 279         u64 llp = 0;
 280
 281         /* Fill the hardware descriptors and link them to a list */
 282         do {
 283                 hw = &desc->hw[--i];
 284                 idma64_hw_desc_fill(hw, config, desc->direction, llp);
 285                 llp = hw->llp;
 286                 desc->length += hw->len;
 287         } while (i);
 288
 289         /* Trigger an interrupt after the last block is transfered */
 290         lli->ctllo |= IDMA64C_CTLL_INT_EN;
 291
 292         /* Disable LLP transfer in the last block */
 293         lli->ctllo &= ~(IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
 294 }
 295
 296 static struct dma_async_tx_descriptor *idma64_prep_slave_sg(
 297                 struct dma_chan *chan, struct scatterlist *sgl,
 298                 unsigned int sg_len, enum dma_transfer_direction direction,
 299                 unsigned long flags, void *context)
 300 {
 301         struct idma64_chan *idma64c = to_idma64_chan(chan);
 302         struct idma64_desc *desc;
 303         struct scatterlist *sg;
 304         unsigned int i;
 305
 306         desc = idma64_alloc_desc(sg_len);
 307         if (!desc)
 308                 return NULL;
 309
 310         for_each_sg(sgl, sg, sg_len, i) {
 311                 struct idma64_hw_desc *hw = &desc->hw[i];
 312
 313                 /* Allocate DMA capable memory for hardware descriptor */
 314                 hw->lli = dma_pool_alloc(idma64c->pool, GFP_NOWAIT, &hw->llp);
 315                 if (!hw->lli) {
 316                         desc->ndesc = i;
 317                         idma64_desc_free(idma64c, desc);
 318                         return NULL;
 319                 }
 320
 321                 hw->phys = sg_dma_address(sg);
 322                 hw->len = sg_dma_len(sg);
 323         }
 324
 325         desc->ndesc = sg_len;
 326         desc->direction = direction;
 327         desc->status = DMA_IN_PROGRESS;
 328
 329         idma64_desc_fill(idma64c, desc);
 330         return vchan_tx_prep(&idma64c->vchan, &desc->vdesc, flags);
 331 }
 332
 333 static void idma64_issue_pending(struct dma_chan *chan)
 334 {
 335         struct idma64_chan *idma64c = to_idma64_chan(chan);
 336         unsigned long flags;
 337
 338         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 339         if (vchan_issue_pending(&idma64c->vchan) && !idma64c->desc)
 340                 idma64_start_transfer(idma64c);
 341         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 342 }
 343
 344 static size_t idma64_active_desc_size(struct idma64_chan *idma64c)
 345 {
 346         struct idma64_desc *desc = idma64c->desc;
 347         struct idma64_hw_desc *hw;
 348         size_t bytes = desc->length;
 349         u64 llp = channel_readq(idma64c, LLP);
 350         u32 ctlhi = channel_readl(idma64c, CTL_HI);
 351         unsigned int i = 0;
 352
 353         do {
 354                 hw = &desc->hw[i];
 355                 if (hw->llp == llp)
 356                         break;
 357                 bytes -= hw->len;
 358         } while (++i < desc->ndesc);
 359
 360         if (!i)
 361                 return bytes;
 362
 363         /* The current chunk is not fully transfered yet */
 364         bytes += desc->hw[--i].len;
 365
 366         return bytes - IDMA64C_CTLH_BLOCK_TS(ctlhi);
 367 }
 368
 369 static enum dma_status idma64_tx_status(struct dma_chan *chan,
 370                 dma_cookie_t cookie, struct dma_tx_state *state)
 371 {
 372         struct idma64_chan *idma64c = to_idma64_chan(chan);
 373         struct virt_dma_desc *vdesc;
 374         enum dma_status status;
 375         size_t bytes;
 376         unsigned long flags;
 377
 378         status = dma_cookie_status(chan, cookie, state);
 379         if (status == DMA_COMPLETE)
 380                 return status;
 381
 382         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 383         vdesc = vchan_find_desc(&idma64c->vchan, cookie);
 384         if (idma64c->desc && cookie == idma64c->desc->vdesc.tx.cookie) {
 385                 bytes = idma64_active_desc_size(idma64c);
 386                 dma_set_residue(state, bytes);
 387                 status = idma64c->desc->status;
 388         } else if (vdesc) {
 389                 bytes = to_idma64_desc(vdesc)->length;
 390                 dma_set_residue(state, bytes);
 391         }
 392         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 393
 394         return status;
 395 }
 396
 397 static void convert_burst(u32 *maxburst)
 398 {
 399         if (*maxburst)
 400                 *maxburst = __fls(*maxburst);
 401         else
 402                 *maxburst = 0;
 403 }
 404
 405 static int idma64_slave_config(struct dma_chan *chan,
 406                 struct dma_slave_config *config)
 407 {
 408         struct idma64_chan *idma64c = to_idma64_chan(chan);
 409
 410         memcpy(&idma64c->config, config, sizeof(idma64c->config));
 411
 412         convert_burst(&idma64c->config.src_maxburst);
 413         convert_burst(&idma64c->config.dst_maxburst);
 414
 415         return 0;
 416 }
 417
 418 static void idma64_chan_deactivate(struct idma64_chan *idma64c, bool drain)
 419 {
 420         unsigned short count = 100;
 421         u32 cfglo;
 422
 423         cfglo = channel_readl(idma64c, CFG_LO);
 424         if (drain)
 425                 cfglo |= IDMA64C_CFGL_CH_DRAIN;
 426         else
 427                 cfglo &= ~IDMA64C_CFGL_CH_DRAIN;
 428
 429         channel_writel(idma64c, CFG_LO, cfglo | IDMA64C_CFGL_CH_SUSP);
 430         do {
 431                 udelay(1);
 432                 cfglo = channel_readl(idma64c, CFG_LO);
 433         } while (!(cfglo & IDMA64C_CFGL_FIFO_EMPTY) && --count);
 434 }
 435
 436 static void idma64_chan_activate(struct idma64_chan *idma64c)
 437 {
 438         u32 cfglo;
 439
 440         cfglo = channel_readl(idma64c, CFG_LO);
 441         channel_writel(idma64c, CFG_LO, cfglo & ~IDMA64C_CFGL_CH_SUSP);
 442 }
 443
 444 static int idma64_pause(struct dma_chan *chan)
 445 {
 446         struct idma64_chan *idma64c = to_idma64_chan(chan);
 447         unsigned long flags;
 448
 449         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 450         if (idma64c->desc && idma64c->desc->status == DMA_IN_PROGRESS) {
 451                 idma64_chan_deactivate(idma64c, false);
 452                 idma64c->desc->status = DMA_PAUSED;
 453         }
 454         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 455
 456         return 0;
 457 }
 458
 459 static int idma64_resume(struct dma_chan *chan)
 460 {
 461         struct idma64_chan *idma64c = to_idma64_chan(chan);
 462         unsigned long flags;
 463
 464         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 465         if (idma64c->desc && idma64c->desc->status == DMA_PAUSED) {
 466                 idma64c->desc->status = DMA_IN_PROGRESS;
 467                 idma64_chan_activate(idma64c);
 468         }
 469         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 470
 471         return 0;
 472 }
 473
 474 static int idma64_terminate_all(struct dma_chan *chan)
 475 {
 476         struct idma64_chan *idma64c = to_idma64_chan(chan);
 477         unsigned long flags;
 478         LIST_HEAD(head);
 479
 480         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 481         idma64_chan_deactivate(idma64c, true);
 482         idma64_stop_transfer(idma64c);
 483         if (idma64c->desc) {
 484                 idma64_vdesc_free(&idma64c->desc->vdesc);
 485                 idma64c->desc = NULL;
 486         }
 487         vchan_get_all_descriptors(&idma64c->vchan, &head);
 488         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 489
 490         vchan_dma_desc_free_list(&idma64c->vchan, &head);
 491         return 0;
 492 }
 493
 494 static void idma64_synchronize(struct dma_chan *chan)
 495 {
 496         struct idma64_chan *idma64c = to_idma64_chan(chan);
 497
 498         vchan_synchronize(&idma64c->vchan);
 499 }
 500
 501 static int idma64_alloc_chan_resources(struct dma_chan *chan)
 502 {
 503         struct idma64_chan *idma64c = to_idma64_chan(chan);
 504
 505         /* Create a pool of consistent memory blocks for hardware descriptors */
 506         idma64c->pool = dma_pool_create(dev_name(chan2dev(chan)),
 507                                         chan->device->dev,
 508                                         sizeof(struct idma64_lli), 8, 0);
 509         if (!idma64c->pool) {
 510                 dev_err(chan2dev(chan), "No memory for descriptors\n");
 511                 return -ENOMEM;
 512         }
 513
 514         return 0;
 515 }
 516
 517 static void idma64_free_chan_resources(struct dma_chan *chan)
 518 {
 519         struct idma64_chan *idma64c = to_idma64_chan(chan);
 520
 521         vchan_free_chan_resources(to_virt_chan(chan));
 522         dma_pool_destroy(idma64c->pool);
 523         idma64c->pool = NULL;
 524 }
 525
 526 /* ---------------------------------------------------------------------- */
 527
 528 #define IDMA64_BUSWIDTHS                                \
 529         BIT(DMA_SLAVE_BUSWIDTH_1_BYTE)          |       \
 530         BIT(DMA_SLAVE_BUSWIDTH_2_BYTES)         |       \
 531         BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
 532
 533 static int idma64_probe(struct idma64_chip *chip)
 534 {
 535         struct idma64 *idma64;
 536         unsigned short nr_chan = IDMA64_NR_CHAN;
 537         unsigned short i;
 538         int ret;
 539
 540         idma64 = devm_kzalloc(chip->dev, sizeof(*idma64), GFP_KERNEL);
 541         if (!idma64)
 542                 return -ENOMEM;
 543
 544         idma64->regs = chip->regs;
 545         chip->idma64 = idma64;
 546
 547         idma64->chan = devm_kcalloc(chip->dev, nr_chan, sizeof(*idma64->chan),
 548                                     GFP_KERNEL);
 549         if (!idma64->chan)
 550                 return -ENOMEM;
 551
 552         idma64->all_chan_mask = (1 << nr_chan) - 1;
 553
 554         /* Turn off iDMA controller */
 555         idma64_off(idma64);
 556
 557         ret = devm_request_irq(chip->dev, chip->irq, idma64_irq, IRQF_SHARED,
 558                                dev_name(chip->dev), idma64);
 559         if (ret)
 560                 return ret;
 561
 562         INIT_LIST_HEAD(&idma64->dma.channels);
 563         for (i = 0; i < nr_chan; i++) {
 564                 struct idma64_chan *idma64c = &idma64->chan[i];
 565
 566                 idma64c->vchan.desc_free = idma64_vdesc_free;
 567                 vchan_init(&idma64c->vchan, &idma64->dma);
 568
 569                 idma64c->regs = idma64->regs + i * IDMA64_CH_LENGTH;
 570                 idma64c->mask = BIT(i);
 571         }
 572
 573         dma_cap_set(DMA_SLAVE, idma64->dma.cap_mask);
 574         dma_cap_set(DMA_PRIVATE, idma64->dma.cap_mask);
 575
 576         idma64->dma.device_alloc_chan_resources = idma64_alloc_chan_resources;
 577         idma64->dma.device_free_chan_resources = idma64_free_chan_resources;
 578
 579         idma64->dma.device_prep_slave_sg = idma64_prep_slave_sg;
 580
 581         idma64->dma.device_issue_pending = idma64_issue_pending;
 582         idma64->dma.device_tx_status = idma64_tx_status;
 583
 584         idma64->dma.device_config = idma64_slave_config;
 585         idma64->dma.device_pause = idma64_pause;
 586         idma64->dma.device_resume = idma64_resume;
 587         idma64->dma.device_terminate_all = idma64_terminate_all;
 588         idma64->dma.device_synchronize = idma64_synchronize;
 589
 590         idma64->dma.src_addr_widths = IDMA64_BUSWIDTHS;
 591         idma64->dma.dst_addr_widths = IDMA64_BUSWIDTHS;
 592         idma64->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
 593         idma64->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 594
 595         idma64->dma.dev = chip->sysdev;
 596
 597         dma_set_max_seg_size(idma64->dma.dev, IDMA64C_CTLH_BLOCK_TS_MASK);
 598
 599         ret = dma_async_device_register(&idma64->dma);
 600         if (ret)
 601                 return ret;
 602
 603         dev_info(chip->dev, "Found Intel integrated DMA 64-bit\n");
 604         return 0;
 605 }
 606
 607 static void idma64_remove(struct idma64_chip *chip)
 608 {
 609         struct idma64 *idma64 = chip->idma64;
 610         unsigned short i;
 611
 612         dma_async_device_unregister(&idma64->dma);
 613
 614         /*
 615          * Explicitly call devm_request_irq() to avoid the side effects with
 616          * the scheduled tasklets.
 617          */
 618         devm_free_irq(chip->dev, chip->irq, idma64);
 619
 620         for (i = 0; i < idma64->dma.chancnt; i++) {
 621                 struct idma64_chan *idma64c = &idma64->chan[i];
 622
 623                 tasklet_kill(&idma64c->vchan.task);
 624         }
 625 }
 626
 627 /* ---------------------------------------------------------------------- */
 628
 629 static int idma64_platform_probe(struct platform_device *pdev)
 630 {
 631         struct idma64_chip *chip;
 632         struct device *dev = &pdev->dev;
 633         struct device *sysdev = dev->parent;
 634         int ret;
 635
 636         chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 637         if (!chip)
 638                 return -ENOMEM;
 639
 640         chip->irq = platform_get_irq(pdev, 0);
 641         if (chip->irq < 0)
 642                 return chip->irq;
 643
 644         chip->regs = devm_platform_ioremap_resource(pdev, 0);
 645         if (IS_ERR(chip->regs))
 646                 return PTR_ERR(chip->regs);
 647
 648         ret = dma_coerce_mask_and_coherent(sysdev, DMA_BIT_MASK(64));
 649         if (ret)
 650                 return ret;
 651
 652         chip->dev = dev;
 653         chip->sysdev = sysdev;
 654
 655         ret = idma64_probe(chip);
 656         if (ret)
 657                 return ret;
 658
 659         platform_set_drvdata(pdev, chip);
 660         return 0;
 661 }
 662
 663 static int idma64_platform_remove(struct platform_device *pdev)
 664 {
 665         struct idma64_chip *chip = platform_get_drvdata(pdev);
 666
 667         idma64_remove(chip);
 668
 669         return 0;
 670 }
 671
 672 static int __maybe_unused idma64_pm_suspend(struct device *dev)
 673 {
 674         struct idma64_chip *chip = dev_get_drvdata(dev);
 675
 676         idma64_off(chip->idma64);
 677         return 0;
 678 }
 679
 680 static int __maybe_unused idma64_pm_resume(struct device *dev)
 681 {
 682         struct idma64_chip *chip = dev_get_drvdata(dev);
 683
 684         idma64_on(chip->idma64);
 685         return 0;
 686 }
 687
 688 static const struct dev_pm_ops idma64_dev_pm_ops = {
 689         SET_SYSTEM_SLEEP_PM_OPS(idma64_pm_suspend, idma64_pm_resume)
 690 };
 691
 692 static struct platform_driver idma64_platform_driver = {
 693         .probe          = idma64_platform_probe,
 694         .remove         = idma64_platform_remove,
 695         .driver = {
 696                 .name   = LPSS_IDMA64_DRIVER_NAME,
 697                 .pm     = &idma64_dev_pm_ops,
 698         },
 699 };
 700
 701 module_platform_driver(idma64_platform_driver);
 702
 703 MODULE_LICENSE("GPL v2");
 704 MODULE_DESCRIPTION("iDMA64 core driver");
 705 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
 706 MODULE_ALIAS("platform:" LPSS_IDMA64_DRIVER_NAME);