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 idma64_desc *desc;
 141
 142         spin_lock(&idma64c->vchan.lock);
 143         desc = idma64c->desc;
 144         if (desc) {
 145                 if (status_err & (1 << c)) {
 146                         dma_writel(idma64, CLEAR(ERROR), idma64c->mask);
 147                         desc->status = DMA_ERROR;
 148                 } else if (status_xfer & (1 << c)) {
 149                         dma_writel(idma64, CLEAR(XFER), idma64c->mask);
 150                         desc->status = DMA_COMPLETE;
 151                         vchan_cookie_complete(&desc->vdesc);
 152                         idma64_start_transfer(idma64c);
 153                 }
 154
 155                 /* idma64_start_transfer() updates idma64c->desc */
 156                 if (idma64c->desc == NULL || desc->status == DMA_ERROR)
 157                         idma64_stop_transfer(idma64c);
 158         }
 159         spin_unlock(&idma64c->vchan.lock);
 160 }
 161
 162 static irqreturn_t idma64_irq(int irq, void *dev)
 163 {
 164         struct idma64 *idma64 = dev;
 165         u32 status = dma_readl(idma64, STATUS_INT);
 166         u32 status_xfer;
 167         u32 status_err;
 168         unsigned short i;
 169
 170         dev_vdbg(idma64->dma.dev, "%s: status=%#x\n", __func__, status);
 171
 172         /* Check if we have any interrupt from the DMA controller */
 173         if (!status)
 174                 return IRQ_NONE;
 175
 176         status_xfer = dma_readl(idma64, RAW(XFER));
 177         status_err = dma_readl(idma64, RAW(ERROR));
 178
 179         for (i = 0; i < idma64->dma.chancnt; i++)
 180                 idma64_chan_irq(idma64, i, status_err, status_xfer);
 181
 182         return IRQ_HANDLED;
 183 }
 184
 185 /* ---------------------------------------------------------------------- */
 186
 187 static struct idma64_desc *idma64_alloc_desc(unsigned int ndesc)
 188 {
 189         struct idma64_desc *desc;
 190
 191         desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
 192         if (!desc)
 193                 return NULL;
 194
 195         desc->hw = kcalloc(ndesc, sizeof(*desc->hw), GFP_NOWAIT);
 196         if (!desc->hw) {
 197                 kfree(desc);
 198                 return NULL;
 199         }
 200
 201         return desc;
 202 }
 203
 204 static void idma64_desc_free(struct idma64_chan *idma64c,
 205                 struct idma64_desc *desc)
 206 {
 207         struct idma64_hw_desc *hw;
 208
 209         if (desc->ndesc) {
 210                 unsigned int i = desc->ndesc;
 211
 212                 do {
 213                         hw = &desc->hw[--i];
 214                         dma_pool_free(idma64c->pool, hw->lli, hw->llp);
 215                 } while (i);
 216         }
 217
 218         kfree(desc->hw);
 219         kfree(desc);
 220 }
 221
 222 static void idma64_vdesc_free(struct virt_dma_desc *vdesc)
 223 {
 224         struct idma64_chan *idma64c = to_idma64_chan(vdesc->tx.chan);
 225
 226         idma64_desc_free(idma64c, to_idma64_desc(vdesc));
 227 }
 228
 229 static void idma64_hw_desc_fill(struct idma64_hw_desc *hw,
 230                 struct dma_slave_config *config,
 231                 enum dma_transfer_direction direction, u64 llp)
 232 {
 233         struct idma64_lli *lli = hw->lli;
 234         u64 sar, dar;
 235         u32 ctlhi = IDMA64C_CTLH_BLOCK_TS(hw->len);
 236         u32 ctllo = IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN;
 237         u32 src_width, dst_width;
 238
 239         if (direction == DMA_MEM_TO_DEV) {
 240                 sar = hw->phys;
 241                 dar = config->dst_addr;
 242                 ctllo |= IDMA64C_CTLL_DST_FIX | IDMA64C_CTLL_SRC_INC |
 243                          IDMA64C_CTLL_FC_M2P;
 244                 src_width = __ffs(sar | hw->len | 4);
 245                 dst_width = __ffs(config->dst_addr_width);
 246         } else {        /* DMA_DEV_TO_MEM */
 247                 sar = config->src_addr;
 248                 dar = hw->phys;
 249                 ctllo |= IDMA64C_CTLL_DST_INC | IDMA64C_CTLL_SRC_FIX |
 250                          IDMA64C_CTLL_FC_P2M;
 251                 src_width = __ffs(config->src_addr_width);
 252                 dst_width = __ffs(dar | hw->len | 4);
 253         }
 254
 255         lli->sar = sar;
 256         lli->dar = dar;
 257
 258         lli->ctlhi = ctlhi;
 259         lli->ctllo = ctllo |
 260                      IDMA64C_CTLL_SRC_MSIZE(config->src_maxburst) |
 261                      IDMA64C_CTLL_DST_MSIZE(config->dst_maxburst) |
 262                      IDMA64C_CTLL_DST_WIDTH(dst_width) |
 263                      IDMA64C_CTLL_SRC_WIDTH(src_width);
 264
 265         lli->llp = llp;
 266 }
 267
 268 static void idma64_desc_fill(struct idma64_chan *idma64c,
 269                 struct idma64_desc *desc)
 270 {
 271         struct dma_slave_config *config = &idma64c->config;
 272         unsigned int i = desc->ndesc;
 273         struct idma64_hw_desc *hw = &desc->hw[i - 1];
 274         struct idma64_lli *lli = hw->lli;
 275         u64 llp = 0;
 276
 277         /* Fill the hardware descriptors and link them to a list */
 278         do {
 279                 hw = &desc->hw[--i];
 280                 idma64_hw_desc_fill(hw, config, desc->direction, llp);
 281                 llp = hw->llp;
 282                 desc->length += hw->len;
 283         } while (i);
 284
 285         /* Trigger an interrupt after the last block is transfered */
 286         lli->ctllo |= IDMA64C_CTLL_INT_EN;
 287
 288         /* Disable LLP transfer in the last block */
 289         lli->ctllo &= ~(IDMA64C_CTLL_LLP_S_EN | IDMA64C_CTLL_LLP_D_EN);
 290 }
 291
 292 static struct dma_async_tx_descriptor *idma64_prep_slave_sg(
 293                 struct dma_chan *chan, struct scatterlist *sgl,
 294                 unsigned int sg_len, enum dma_transfer_direction direction,
 295                 unsigned long flags, void *context)
 296 {
 297         struct idma64_chan *idma64c = to_idma64_chan(chan);
 298         struct idma64_desc *desc;
 299         struct scatterlist *sg;
 300         unsigned int i;
 301
 302         desc = idma64_alloc_desc(sg_len);
 303         if (!desc)
 304                 return NULL;
 305
 306         for_each_sg(sgl, sg, sg_len, i) {
 307                 struct idma64_hw_desc *hw = &desc->hw[i];
 308
 309                 /* Allocate DMA capable memory for hardware descriptor */
 310                 hw->lli = dma_pool_alloc(idma64c->pool, GFP_NOWAIT, &hw->llp);
 311                 if (!hw->lli) {
 312                         desc->ndesc = i;
 313                         idma64_desc_free(idma64c, desc);
 314                         return NULL;
 315                 }
 316
 317                 hw->phys = sg_dma_address(sg);
 318                 hw->len = sg_dma_len(sg);
 319         }
 320
 321         desc->ndesc = sg_len;
 322         desc->direction = direction;
 323         desc->status = DMA_IN_PROGRESS;
 324
 325         idma64_desc_fill(idma64c, desc);
 326         return vchan_tx_prep(&idma64c->vchan, &desc->vdesc, flags);
 327 }
 328
 329 static void idma64_issue_pending(struct dma_chan *chan)
 330 {
 331         struct idma64_chan *idma64c = to_idma64_chan(chan);
 332         unsigned long flags;
 333
 334         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 335         if (vchan_issue_pending(&idma64c->vchan) && !idma64c->desc)
 336                 idma64_start_transfer(idma64c);
 337         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 338 }
 339
 340 static size_t idma64_active_desc_size(struct idma64_chan *idma64c)
 341 {
 342         struct idma64_desc *desc = idma64c->desc;
 343         struct idma64_hw_desc *hw;
 344         size_t bytes = desc->length;
 345         u64 llp = channel_readq(idma64c, LLP);
 346         u32 ctlhi = channel_readl(idma64c, CTL_HI);
 347         unsigned int i = 0;
 348
 349         do {
 350                 hw = &desc->hw[i];
 351                 if (hw->llp == llp)
 352                         break;
 353                 bytes -= hw->len;
 354         } while (++i < desc->ndesc);
 355
 356         if (!i)
 357                 return bytes;
 358
 359         /* The current chunk is not fully transfered yet */
 360         bytes += desc->hw[--i].len;
 361
 362         return bytes - IDMA64C_CTLH_BLOCK_TS(ctlhi);
 363 }
 364
 365 static enum dma_status idma64_tx_status(struct dma_chan *chan,
 366                 dma_cookie_t cookie, struct dma_tx_state *state)
 367 {
 368         struct idma64_chan *idma64c = to_idma64_chan(chan);
 369         struct virt_dma_desc *vdesc;
 370         enum dma_status status;
 371         size_t bytes;
 372         unsigned long flags;
 373
 374         status = dma_cookie_status(chan, cookie, state);
 375         if (status == DMA_COMPLETE)
 376                 return status;
 377
 378         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 379         vdesc = vchan_find_desc(&idma64c->vchan, cookie);
 380         if (idma64c->desc && cookie == idma64c->desc->vdesc.tx.cookie) {
 381                 bytes = idma64_active_desc_size(idma64c);
 382                 dma_set_residue(state, bytes);
 383                 status = idma64c->desc->status;
 384         } else if (vdesc) {
 385                 bytes = to_idma64_desc(vdesc)->length;
 386                 dma_set_residue(state, bytes);
 387         }
 388         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 389
 390         return status;
 391 }
 392
 393 static void convert_burst(u32 *maxburst)
 394 {
 395         if (*maxburst)
 396                 *maxburst = __fls(*maxburst);
 397         else
 398                 *maxburst = 0;
 399 }
 400
 401 static int idma64_slave_config(struct dma_chan *chan,
 402                 struct dma_slave_config *config)
 403 {
 404         struct idma64_chan *idma64c = to_idma64_chan(chan);
 405
 406         memcpy(&idma64c->config, config, sizeof(idma64c->config));
 407
 408         convert_burst(&idma64c->config.src_maxburst);
 409         convert_burst(&idma64c->config.dst_maxburst);
 410
 411         return 0;
 412 }
 413
 414 static void idma64_chan_deactivate(struct idma64_chan *idma64c, bool drain)
 415 {
 416         unsigned short count = 100;
 417         u32 cfglo;
 418
 419         cfglo = channel_readl(idma64c, CFG_LO);
 420         if (drain)
 421                 cfglo |= IDMA64C_CFGL_CH_DRAIN;
 422         else
 423                 cfglo &= ~IDMA64C_CFGL_CH_DRAIN;
 424
 425         channel_writel(idma64c, CFG_LO, cfglo | IDMA64C_CFGL_CH_SUSP);
 426         do {
 427                 udelay(1);
 428                 cfglo = channel_readl(idma64c, CFG_LO);
 429         } while (!(cfglo & IDMA64C_CFGL_FIFO_EMPTY) && --count);
 430 }
 431
 432 static void idma64_chan_activate(struct idma64_chan *idma64c)
 433 {
 434         u32 cfglo;
 435
 436         cfglo = channel_readl(idma64c, CFG_LO);
 437         channel_writel(idma64c, CFG_LO, cfglo & ~IDMA64C_CFGL_CH_SUSP);
 438 }
 439
 440 static int idma64_pause(struct dma_chan *chan)
 441 {
 442         struct idma64_chan *idma64c = to_idma64_chan(chan);
 443         unsigned long flags;
 444
 445         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 446         if (idma64c->desc && idma64c->desc->status == DMA_IN_PROGRESS) {
 447                 idma64_chan_deactivate(idma64c, false);
 448                 idma64c->desc->status = DMA_PAUSED;
 449         }
 450         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 451
 452         return 0;
 453 }
 454
 455 static int idma64_resume(struct dma_chan *chan)
 456 {
 457         struct idma64_chan *idma64c = to_idma64_chan(chan);
 458         unsigned long flags;
 459
 460         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 461         if (idma64c->desc && idma64c->desc->status == DMA_PAUSED) {
 462                 idma64c->desc->status = DMA_IN_PROGRESS;
 463                 idma64_chan_activate(idma64c);
 464         }
 465         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 466
 467         return 0;
 468 }
 469
 470 static int idma64_terminate_all(struct dma_chan *chan)
 471 {
 472         struct idma64_chan *idma64c = to_idma64_chan(chan);
 473         unsigned long flags;
 474         LIST_HEAD(head);
 475
 476         spin_lock_irqsave(&idma64c->vchan.lock, flags);
 477         idma64_chan_deactivate(idma64c, true);
 478         idma64_stop_transfer(idma64c);
 479         if (idma64c->desc) {
 480                 idma64_vdesc_free(&idma64c->desc->vdesc);
 481                 idma64c->desc = NULL;
 482         }
 483         vchan_get_all_descriptors(&idma64c->vchan, &head);
 484         spin_unlock_irqrestore(&idma64c->vchan.lock, flags);
 485
 486         vchan_dma_desc_free_list(&idma64c->vchan, &head);
 487         return 0;
 488 }
 489
 490 static void idma64_synchronize(struct dma_chan *chan)
 491 {
 492         struct idma64_chan *idma64c = to_idma64_chan(chan);
 493
 494         vchan_synchronize(&idma64c->vchan);
 495 }
 496
 497 static int idma64_alloc_chan_resources(struct dma_chan *chan)
 498 {
 499         struct idma64_chan *idma64c = to_idma64_chan(chan);
 500
 501         /* Create a pool of consistent memory blocks for hardware descriptors */
 502         idma64c->pool = dma_pool_create(dev_name(chan2dev(chan)),
 503                                         chan->device->dev,
 504                                         sizeof(struct idma64_lli), 8, 0);
 505         if (!idma64c->pool) {
 506                 dev_err(chan2dev(chan), "No memory for descriptors\n");
 507                 return -ENOMEM;
 508         }
 509
 510         return 0;
 511 }
 512
 513 static void idma64_free_chan_resources(struct dma_chan *chan)
 514 {
 515         struct idma64_chan *idma64c = to_idma64_chan(chan);
 516
 517         vchan_free_chan_resources(to_virt_chan(chan));
 518         dma_pool_destroy(idma64c->pool);
 519         idma64c->pool = NULL;
 520 }
 521
 522 /* ---------------------------------------------------------------------- */
 523
 524 #define IDMA64_BUSWIDTHS                                \
 525         BIT(DMA_SLAVE_BUSWIDTH_1_BYTE)          |       \
 526         BIT(DMA_SLAVE_BUSWIDTH_2_BYTES)         |       \
 527         BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)
 528
 529 static int idma64_probe(struct idma64_chip *chip)
 530 {
 531         struct idma64 *idma64;
 532         unsigned short nr_chan = IDMA64_NR_CHAN;
 533         unsigned short i;
 534         int ret;
 535
 536         idma64 = devm_kzalloc(chip->dev, sizeof(*idma64), GFP_KERNEL);
 537         if (!idma64)
 538                 return -ENOMEM;
 539
 540         idma64->regs = chip->regs;
 541         chip->idma64 = idma64;
 542
 543         idma64->chan = devm_kcalloc(chip->dev, nr_chan, sizeof(*idma64->chan),
 544                                     GFP_KERNEL);
 545         if (!idma64->chan)
 546                 return -ENOMEM;
 547
 548         idma64->all_chan_mask = (1 << nr_chan) - 1;
 549
 550         /* Turn off iDMA controller */
 551         idma64_off(idma64);
 552
 553         ret = devm_request_irq(chip->dev, chip->irq, idma64_irq, IRQF_SHARED,
 554                                dev_name(chip->dev), idma64);
 555         if (ret)
 556                 return ret;
 557
 558         INIT_LIST_HEAD(&idma64->dma.channels);
 559         for (i = 0; i < nr_chan; i++) {
 560                 struct idma64_chan *idma64c = &idma64->chan[i];
 561
 562                 idma64c->vchan.desc_free = idma64_vdesc_free;
 563                 vchan_init(&idma64c->vchan, &idma64->dma);
 564
 565                 idma64c->regs = idma64->regs + i * IDMA64_CH_LENGTH;
 566                 idma64c->mask = BIT(i);
 567         }
 568
 569         dma_cap_set(DMA_SLAVE, idma64->dma.cap_mask);
 570         dma_cap_set(DMA_PRIVATE, idma64->dma.cap_mask);
 571
 572         idma64->dma.device_alloc_chan_resources = idma64_alloc_chan_resources;
 573         idma64->dma.device_free_chan_resources = idma64_free_chan_resources;
 574
 575         idma64->dma.device_prep_slave_sg = idma64_prep_slave_sg;
 576
 577         idma64->dma.device_issue_pending = idma64_issue_pending;
 578         idma64->dma.device_tx_status = idma64_tx_status;
 579
 580         idma64->dma.device_config = idma64_slave_config;
 581         idma64->dma.device_pause = idma64_pause;
 582         idma64->dma.device_resume = idma64_resume;
 583         idma64->dma.device_terminate_all = idma64_terminate_all;
 584         idma64->dma.device_synchronize = idma64_synchronize;
 585
 586         idma64->dma.src_addr_widths = IDMA64_BUSWIDTHS;
 587         idma64->dma.dst_addr_widths = IDMA64_BUSWIDTHS;
 588         idma64->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
 589         idma64->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 590
 591         idma64->dma.dev = chip->sysdev;
 592
 593         dma_set_max_seg_size(idma64->dma.dev, IDMA64C_CTLH_BLOCK_TS_MASK);
 594
 595         ret = dma_async_device_register(&idma64->dma);
 596         if (ret)
 597                 return ret;
 598
 599         dev_info(chip->dev, "Found Intel integrated DMA 64-bit\n");
 600         return 0;
 601 }
 602
 603 static int idma64_remove(struct idma64_chip *chip)
 604 {
 605         struct idma64 *idma64 = chip->idma64;
 606         unsigned short i;
 607
 608         dma_async_device_unregister(&idma64->dma);
 609
 610         /*
 611          * Explicitly call devm_request_irq() to avoid the side effects with
 612          * the scheduled tasklets.
 613          */
 614         devm_free_irq(chip->dev, chip->irq, idma64);
 615
 616         for (i = 0; i < idma64->dma.chancnt; i++) {
 617                 struct idma64_chan *idma64c = &idma64->chan[i];
 618
 619                 tasklet_kill(&idma64c->vchan.task);
 620         }
 621
 622         return 0;
 623 }
 624
 625 /* ---------------------------------------------------------------------- */
 626
 627 static int idma64_platform_probe(struct platform_device *pdev)
 628 {
 629         struct idma64_chip *chip;
 630         struct device *dev = &pdev->dev;
 631         struct device *sysdev = dev->parent;
 632         struct resource *mem;
 633         int ret;
 634
 635         chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
 636         if (!chip)
 637                 return -ENOMEM;
 638
 639         chip->irq = platform_get_irq(pdev, 0);
 640         if (chip->irq < 0)
 641                 return chip->irq;
 642
 643         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 644         chip->regs = devm_ioremap_resource(dev, mem);
 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         return idma64_remove(chip);
 668 }
 669
 670 static int __maybe_unused idma64_pm_suspend(struct device *dev)
 671 {
 672         struct idma64_chip *chip = dev_get_drvdata(dev);
 673
 674         idma64_off(chip->idma64);
 675         return 0;
 676 }
 677
 678 static int __maybe_unused idma64_pm_resume(struct device *dev)
 679 {
 680         struct idma64_chip *chip = dev_get_drvdata(dev);
 681
 682         idma64_on(chip->idma64);
 683         return 0;
 684 }
 685
 686 static const struct dev_pm_ops idma64_dev_pm_ops = {
 687         SET_SYSTEM_SLEEP_PM_OPS(idma64_pm_suspend, idma64_pm_resume)
 688 };
 689
 690 static struct platform_driver idma64_platform_driver = {
 691         .probe          = idma64_platform_probe,
 692         .remove         = idma64_platform_remove,
 693         .driver = {
 694                 .name   = LPSS_IDMA64_DRIVER_NAME,
 695                 .pm     = &idma64_dev_pm_ops,
 696         },
 697 };
 698
 699 module_platform_driver(idma64_platform_driver);
 700
 701 MODULE_LICENSE("GPL v2");
 702 MODULE_DESCRIPTION("iDMA64 core driver");
 703 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
 704 MODULE_ALIAS("platform:" LPSS_IDMA64_DRIVER_NAME);