1 /* 2 * MOXA ART SoCs DMA Engine support. 3 * 4 * Copyright (C) 2013 Jonas Jensen 5 * 6 * Jonas Jensen <jonas.jensen@gmail.com> 7 * 8 * This file is licensed under the terms of the GNU General Public 9 * License version 2. This program is licensed "as is" without any 10 * warranty of any kind, whether express or implied. 11 */ 12 13 #include <linux/dmaengine.h> 14 #include <linux/dma-mapping.h> 15 #include <linux/err.h> 16 #include <linux/init.h> 17 #include <linux/interrupt.h> 18 #include <linux/list.h> 19 #include <linux/module.h> 20 #include <linux/platform_device.h> 21 #include <linux/slab.h> 22 #include <linux/spinlock.h> 23 #include <linux/of_address.h> 24 #include <linux/of_irq.h> 25 #include <linux/of_dma.h> 26 #include <linux/bitops.h> 27 28 #include <asm/cacheflush.h> 29 30 #include "dmaengine.h" 31 #include "virt-dma.h" 32 33 #define APB_DMA_MAX_CHANNEL 4 34 35 #define REG_OFF_ADDRESS_SOURCE 0 36 #define REG_OFF_ADDRESS_DEST 4 37 #define REG_OFF_CYCLES 8 38 #define REG_OFF_CTRL 12 39 #define REG_OFF_CHAN_SIZE 16 40 41 #define APB_DMA_ENABLE BIT(0) 42 #define APB_DMA_FIN_INT_STS BIT(1) 43 #define APB_DMA_FIN_INT_EN BIT(2) 44 #define APB_DMA_BURST_MODE BIT(3) 45 #define APB_DMA_ERR_INT_STS BIT(4) 46 #define APB_DMA_ERR_INT_EN BIT(5) 47 48 /* 49 * Unset: APB 50 * Set: AHB 51 */ 52 #define APB_DMA_SOURCE_SELECT 0x40 53 #define APB_DMA_DEST_SELECT 0x80 54 55 #define APB_DMA_SOURCE 0x100 56 #define APB_DMA_DEST 0x1000 57 58 #define APB_DMA_SOURCE_MASK 0x700 59 #define APB_DMA_DEST_MASK 0x7000 60 61 /* 62 * 000: No increment 63 * 001: +1 (Burst=0), +4 (Burst=1) 64 * 010: +2 (Burst=0), +8 (Burst=1) 65 * 011: +4 (Burst=0), +16 (Burst=1) 66 * 101: -1 (Burst=0), -4 (Burst=1) 67 * 110: -2 (Burst=0), -8 (Burst=1) 68 * 111: -4 (Burst=0), -16 (Burst=1) 69 */ 70 #define APB_DMA_SOURCE_INC_0 0 71 #define APB_DMA_SOURCE_INC_1_4 0x100 72 #define APB_DMA_SOURCE_INC_2_8 0x200 73 #define APB_DMA_SOURCE_INC_4_16 0x300 74 #define APB_DMA_SOURCE_DEC_1_4 0x500 75 #define APB_DMA_SOURCE_DEC_2_8 0x600 76 #define APB_DMA_SOURCE_DEC_4_16 0x700 77 #define APB_DMA_DEST_INC_0 0 78 #define APB_DMA_DEST_INC_1_4 0x1000 79 #define APB_DMA_DEST_INC_2_8 0x2000 80 #define APB_DMA_DEST_INC_4_16 0x3000 81 #define APB_DMA_DEST_DEC_1_4 0x5000 82 #define APB_DMA_DEST_DEC_2_8 0x6000 83 #define APB_DMA_DEST_DEC_4_16 0x7000 84 85 /* 86 * Request signal select source/destination address for DMA hardware handshake. 87 * 88 * The request line number is a property of the DMA controller itself, 89 * e.g. MMC must always request channels where dma_slave_config->slave_id is 5. 90 * 91 * 0: No request / Grant signal 92 * 1-15: Request / Grant signal 93 */ 94 #define APB_DMA_SOURCE_REQ_NO 0x1000000 95 #define APB_DMA_SOURCE_REQ_NO_MASK 0xf000000 96 #define APB_DMA_DEST_REQ_NO 0x10000 97 #define APB_DMA_DEST_REQ_NO_MASK 0xf0000 98 99 #define APB_DMA_DATA_WIDTH 0x100000 100 #define APB_DMA_DATA_WIDTH_MASK 0x300000 101 /* 102 * Data width of transfer: 103 * 104 * 00: Word 105 * 01: Half 106 * 10: Byte 107 */ 108 #define APB_DMA_DATA_WIDTH_4 0 109 #define APB_DMA_DATA_WIDTH_2 0x100000 110 #define APB_DMA_DATA_WIDTH_1 0x200000 111 112 #define APB_DMA_CYCLES_MASK 0x00ffffff 113 114 #define MOXART_DMA_DATA_TYPE_S8 0x00 115 #define MOXART_DMA_DATA_TYPE_S16 0x01 116 #define MOXART_DMA_DATA_TYPE_S32 0x02 117 118 struct moxart_sg { 119 dma_addr_t addr; 120 uint32_t len; 121 }; 122 123 struct moxart_desc { 124 enum dma_transfer_direction dma_dir; 125 dma_addr_t dev_addr; 126 unsigned int sglen; 127 unsigned int dma_cycles; 128 struct virt_dma_desc vd; 129 uint8_t es; 130 struct moxart_sg sg[0]; 131 }; 132 133 struct moxart_chan { 134 struct virt_dma_chan vc; 135 136 void __iomem *base; 137 struct moxart_desc *desc; 138 139 struct dma_slave_config cfg; 140 141 bool allocated; 142 bool error; 143 int ch_num; 144 unsigned int line_reqno; 145 unsigned int sgidx; 146 }; 147 148 struct moxart_dmadev { 149 struct dma_device dma_slave; 150 struct moxart_chan slave_chans[APB_DMA_MAX_CHANNEL]; 151 }; 152 153 struct moxart_filter_data { 154 struct moxart_dmadev *mdc; 155 struct of_phandle_args *dma_spec; 156 }; 157 158 static const unsigned int es_bytes[] = { 159 [MOXART_DMA_DATA_TYPE_S8] = 1, 160 [MOXART_DMA_DATA_TYPE_S16] = 2, 161 [MOXART_DMA_DATA_TYPE_S32] = 4, 162 }; 163 164 static struct device *chan2dev(struct dma_chan *chan) 165 { 166 return &chan->dev->device; 167 } 168 169 static inline struct moxart_chan *to_moxart_dma_chan(struct dma_chan *c) 170 { 171 return container_of(c, struct moxart_chan, vc.chan); 172 } 173 174 static inline struct moxart_desc *to_moxart_dma_desc( 175 struct dma_async_tx_descriptor *t) 176 { 177 return container_of(t, struct moxart_desc, vd.tx); 178 } 179 180 static void moxart_dma_desc_free(struct virt_dma_desc *vd) 181 { 182 kfree(container_of(vd, struct moxart_desc, vd)); 183 } 184 185 static int moxart_terminate_all(struct dma_chan *chan) 186 { 187 struct moxart_chan *ch = to_moxart_dma_chan(chan); 188 unsigned long flags; 189 LIST_HEAD(head); 190 u32 ctrl; 191 192 dev_dbg(chan2dev(chan), "%s: ch=%p\n", __func__, ch); 193 194 spin_lock_irqsave(&ch->vc.lock, flags); 195 196 if (ch->desc) { 197 moxart_dma_desc_free(&ch->desc->vd); 198 ch->desc = NULL; 199 } 200 201 ctrl = readl(ch->base + REG_OFF_CTRL); 202 ctrl &= ~(APB_DMA_ENABLE | APB_DMA_FIN_INT_EN | APB_DMA_ERR_INT_EN); 203 writel(ctrl, ch->base + REG_OFF_CTRL); 204 205 vchan_get_all_descriptors(&ch->vc, &head); 206 spin_unlock_irqrestore(&ch->vc.lock, flags); 207 vchan_dma_desc_free_list(&ch->vc, &head); 208 209 return 0; 210 } 211 212 static int moxart_slave_config(struct dma_chan *chan, 213 struct dma_slave_config *cfg) 214 { 215 struct moxart_chan *ch = to_moxart_dma_chan(chan); 216 u32 ctrl; 217 218 ch->cfg = *cfg; 219 220 ctrl = readl(ch->base + REG_OFF_CTRL); 221 ctrl |= APB_DMA_BURST_MODE; 222 ctrl &= ~(APB_DMA_DEST_MASK | APB_DMA_SOURCE_MASK); 223 ctrl &= ~(APB_DMA_DEST_REQ_NO_MASK | APB_DMA_SOURCE_REQ_NO_MASK); 224 225 switch (ch->cfg.src_addr_width) { 226 case DMA_SLAVE_BUSWIDTH_1_BYTE: 227 ctrl |= APB_DMA_DATA_WIDTH_1; 228 if (ch->cfg.direction != DMA_MEM_TO_DEV) 229 ctrl |= APB_DMA_DEST_INC_1_4; 230 else 231 ctrl |= APB_DMA_SOURCE_INC_1_4; 232 break; 233 case DMA_SLAVE_BUSWIDTH_2_BYTES: 234 ctrl |= APB_DMA_DATA_WIDTH_2; 235 if (ch->cfg.direction != DMA_MEM_TO_DEV) 236 ctrl |= APB_DMA_DEST_INC_2_8; 237 else 238 ctrl |= APB_DMA_SOURCE_INC_2_8; 239 break; 240 case DMA_SLAVE_BUSWIDTH_4_BYTES: 241 ctrl &= ~APB_DMA_DATA_WIDTH; 242 if (ch->cfg.direction != DMA_MEM_TO_DEV) 243 ctrl |= APB_DMA_DEST_INC_4_16; 244 else 245 ctrl |= APB_DMA_SOURCE_INC_4_16; 246 break; 247 default: 248 return -EINVAL; 249 } 250 251 if (ch->cfg.direction == DMA_MEM_TO_DEV) { 252 ctrl &= ~APB_DMA_DEST_SELECT; 253 ctrl |= APB_DMA_SOURCE_SELECT; 254 ctrl |= (ch->line_reqno << 16 & 255 APB_DMA_DEST_REQ_NO_MASK); 256 } else { 257 ctrl |= APB_DMA_DEST_SELECT; 258 ctrl &= ~APB_DMA_SOURCE_SELECT; 259 ctrl |= (ch->line_reqno << 24 & 260 APB_DMA_SOURCE_REQ_NO_MASK); 261 } 262 263 writel(ctrl, ch->base + REG_OFF_CTRL); 264 265 return 0; 266 } 267 268 static struct dma_async_tx_descriptor *moxart_prep_slave_sg( 269 struct dma_chan *chan, struct scatterlist *sgl, 270 unsigned int sg_len, enum dma_transfer_direction dir, 271 unsigned long tx_flags, void *context) 272 { 273 struct moxart_chan *ch = to_moxart_dma_chan(chan); 274 struct moxart_desc *d; 275 enum dma_slave_buswidth dev_width; 276 dma_addr_t dev_addr; 277 struct scatterlist *sgent; 278 unsigned int es; 279 unsigned int i; 280 281 if (!is_slave_direction(dir)) { 282 dev_err(chan2dev(chan), "%s: invalid DMA direction\n", 283 __func__); 284 return NULL; 285 } 286 287 if (dir == DMA_DEV_TO_MEM) { 288 dev_addr = ch->cfg.src_addr; 289 dev_width = ch->cfg.src_addr_width; 290 } else { 291 dev_addr = ch->cfg.dst_addr; 292 dev_width = ch->cfg.dst_addr_width; 293 } 294 295 switch (dev_width) { 296 case DMA_SLAVE_BUSWIDTH_1_BYTE: 297 es = MOXART_DMA_DATA_TYPE_S8; 298 break; 299 case DMA_SLAVE_BUSWIDTH_2_BYTES: 300 es = MOXART_DMA_DATA_TYPE_S16; 301 break; 302 case DMA_SLAVE_BUSWIDTH_4_BYTES: 303 es = MOXART_DMA_DATA_TYPE_S32; 304 break; 305 default: 306 dev_err(chan2dev(chan), "%s: unsupported data width (%u)\n", 307 __func__, dev_width); 308 return NULL; 309 } 310 311 d = kzalloc(sizeof(*d) + sg_len * sizeof(d->sg[0]), GFP_ATOMIC); 312 if (!d) 313 return NULL; 314 315 d->dma_dir = dir; 316 d->dev_addr = dev_addr; 317 d->es = es; 318 319 for_each_sg(sgl, sgent, sg_len, i) { 320 d->sg[i].addr = sg_dma_address(sgent); 321 d->sg[i].len = sg_dma_len(sgent); 322 } 323 324 d->sglen = sg_len; 325 326 ch->error = 0; 327 328 return vchan_tx_prep(&ch->vc, &d->vd, tx_flags); 329 } 330 331 static struct dma_chan *moxart_of_xlate(struct of_phandle_args *dma_spec, 332 struct of_dma *ofdma) 333 { 334 struct moxart_dmadev *mdc = ofdma->of_dma_data; 335 struct dma_chan *chan; 336 struct moxart_chan *ch; 337 338 chan = dma_get_any_slave_channel(&mdc->dma_slave); 339 if (!chan) 340 return NULL; 341 342 ch = to_moxart_dma_chan(chan); 343 ch->line_reqno = dma_spec->args[0]; 344 345 return chan; 346 } 347 348 static int moxart_alloc_chan_resources(struct dma_chan *chan) 349 { 350 struct moxart_chan *ch = to_moxart_dma_chan(chan); 351 352 dev_dbg(chan2dev(chan), "%s: allocating channel #%u\n", 353 __func__, ch->ch_num); 354 ch->allocated = 1; 355 356 return 0; 357 } 358 359 static void moxart_free_chan_resources(struct dma_chan *chan) 360 { 361 struct moxart_chan *ch = to_moxart_dma_chan(chan); 362 363 vchan_free_chan_resources(&ch->vc); 364 365 dev_dbg(chan2dev(chan), "%s: freeing channel #%u\n", 366 __func__, ch->ch_num); 367 ch->allocated = 0; 368 } 369 370 static void moxart_dma_set_params(struct moxart_chan *ch, dma_addr_t src_addr, 371 dma_addr_t dst_addr) 372 { 373 writel(src_addr, ch->base + REG_OFF_ADDRESS_SOURCE); 374 writel(dst_addr, ch->base + REG_OFF_ADDRESS_DEST); 375 } 376 377 static void moxart_set_transfer_params(struct moxart_chan *ch, unsigned int len) 378 { 379 struct moxart_desc *d = ch->desc; 380 unsigned int sglen_div = es_bytes[d->es]; 381 382 d->dma_cycles = len >> sglen_div; 383 384 /* 385 * There are 4 cycles on 64 bytes copied, i.e. one cycle copies 16 386 * bytes ( when width is APB_DMAB_DATA_WIDTH_4 ). 387 */ 388 writel(d->dma_cycles, ch->base + REG_OFF_CYCLES); 389 390 dev_dbg(chan2dev(&ch->vc.chan), "%s: set %u DMA cycles (len=%u)\n", 391 __func__, d->dma_cycles, len); 392 } 393 394 static void moxart_start_dma(struct moxart_chan *ch) 395 { 396 u32 ctrl; 397 398 ctrl = readl(ch->base + REG_OFF_CTRL); 399 ctrl |= (APB_DMA_ENABLE | APB_DMA_FIN_INT_EN | APB_DMA_ERR_INT_EN); 400 writel(ctrl, ch->base + REG_OFF_CTRL); 401 } 402 403 static void moxart_dma_start_sg(struct moxart_chan *ch, unsigned int idx) 404 { 405 struct moxart_desc *d = ch->desc; 406 struct moxart_sg *sg = ch->desc->sg + idx; 407 408 if (ch->desc->dma_dir == DMA_MEM_TO_DEV) 409 moxart_dma_set_params(ch, sg->addr, d->dev_addr); 410 else if (ch->desc->dma_dir == DMA_DEV_TO_MEM) 411 moxart_dma_set_params(ch, d->dev_addr, sg->addr); 412 413 moxart_set_transfer_params(ch, sg->len); 414 415 moxart_start_dma(ch); 416 } 417 418 static void moxart_dma_start_desc(struct dma_chan *chan) 419 { 420 struct moxart_chan *ch = to_moxart_dma_chan(chan); 421 struct virt_dma_desc *vd; 422 423 vd = vchan_next_desc(&ch->vc); 424 425 if (!vd) { 426 ch->desc = NULL; 427 return; 428 } 429 430 list_del(&vd->node); 431 432 ch->desc = to_moxart_dma_desc(&vd->tx); 433 ch->sgidx = 0; 434 435 moxart_dma_start_sg(ch, 0); 436 } 437 438 static void moxart_issue_pending(struct dma_chan *chan) 439 { 440 struct moxart_chan *ch = to_moxart_dma_chan(chan); 441 unsigned long flags; 442 443 spin_lock_irqsave(&ch->vc.lock, flags); 444 if (vchan_issue_pending(&ch->vc) && !ch->desc) 445 moxart_dma_start_desc(chan); 446 spin_unlock_irqrestore(&ch->vc.lock, flags); 447 } 448 449 static size_t moxart_dma_desc_size(struct moxart_desc *d, 450 unsigned int completed_sgs) 451 { 452 unsigned int i; 453 size_t size; 454 455 for (size = i = completed_sgs; i < d->sglen; i++) 456 size += d->sg[i].len; 457 458 return size; 459 } 460 461 static size_t moxart_dma_desc_size_in_flight(struct moxart_chan *ch) 462 { 463 size_t size; 464 unsigned int completed_cycles, cycles; 465 466 size = moxart_dma_desc_size(ch->desc, ch->sgidx); 467 cycles = readl(ch->base + REG_OFF_CYCLES); 468 completed_cycles = (ch->desc->dma_cycles - cycles); 469 size -= completed_cycles << es_bytes[ch->desc->es]; 470 471 dev_dbg(chan2dev(&ch->vc.chan), "%s: size=%zu\n", __func__, size); 472 473 return size; 474 } 475 476 static enum dma_status moxart_tx_status(struct dma_chan *chan, 477 dma_cookie_t cookie, 478 struct dma_tx_state *txstate) 479 { 480 struct moxart_chan *ch = to_moxart_dma_chan(chan); 481 struct virt_dma_desc *vd; 482 struct moxart_desc *d; 483 enum dma_status ret; 484 unsigned long flags; 485 486 /* 487 * dma_cookie_status() assigns initial residue value. 488 */ 489 ret = dma_cookie_status(chan, cookie, txstate); 490 491 spin_lock_irqsave(&ch->vc.lock, flags); 492 vd = vchan_find_desc(&ch->vc, cookie); 493 if (vd) { 494 d = to_moxart_dma_desc(&vd->tx); 495 txstate->residue = moxart_dma_desc_size(d, 0); 496 } else if (ch->desc && ch->desc->vd.tx.cookie == cookie) { 497 txstate->residue = moxart_dma_desc_size_in_flight(ch); 498 } 499 spin_unlock_irqrestore(&ch->vc.lock, flags); 500 501 if (ch->error) 502 return DMA_ERROR; 503 504 return ret; 505 } 506 507 static void moxart_dma_init(struct dma_device *dma, struct device *dev) 508 { 509 dma->device_prep_slave_sg = moxart_prep_slave_sg; 510 dma->device_alloc_chan_resources = moxart_alloc_chan_resources; 511 dma->device_free_chan_resources = moxart_free_chan_resources; 512 dma->device_issue_pending = moxart_issue_pending; 513 dma->device_tx_status = moxart_tx_status; 514 dma->device_config = moxart_slave_config; 515 dma->device_terminate_all = moxart_terminate_all; 516 dma->dev = dev; 517 518 INIT_LIST_HEAD(&dma->channels); 519 } 520 521 static irqreturn_t moxart_dma_interrupt(int irq, void *devid) 522 { 523 struct moxart_dmadev *mc = devid; 524 struct moxart_chan *ch = &mc->slave_chans[0]; 525 unsigned int i; 526 unsigned long flags; 527 u32 ctrl; 528 529 dev_dbg(chan2dev(&ch->vc.chan), "%s\n", __func__); 530 531 for (i = 0; i < APB_DMA_MAX_CHANNEL; i++, ch++) { 532 if (!ch->allocated) 533 continue; 534 535 ctrl = readl(ch->base + REG_OFF_CTRL); 536 537 dev_dbg(chan2dev(&ch->vc.chan), "%s: ch=%p ch->base=%p ctrl=%x\n", 538 __func__, ch, ch->base, ctrl); 539 540 if (ctrl & APB_DMA_FIN_INT_STS) { 541 ctrl &= ~APB_DMA_FIN_INT_STS; 542 if (ch->desc) { 543 spin_lock_irqsave(&ch->vc.lock, flags); 544 if (++ch->sgidx < ch->desc->sglen) { 545 moxart_dma_start_sg(ch, ch->sgidx); 546 } else { 547 vchan_cookie_complete(&ch->desc->vd); 548 moxart_dma_start_desc(&ch->vc.chan); 549 } 550 spin_unlock_irqrestore(&ch->vc.lock, flags); 551 } 552 } 553 554 if (ctrl & APB_DMA_ERR_INT_STS) { 555 ctrl &= ~APB_DMA_ERR_INT_STS; 556 ch->error = 1; 557 } 558 559 writel(ctrl, ch->base + REG_OFF_CTRL); 560 } 561 562 return IRQ_HANDLED; 563 } 564 565 static int moxart_probe(struct platform_device *pdev) 566 { 567 struct device *dev = &pdev->dev; 568 struct device_node *node = dev->of_node; 569 struct resource *res; 570 static void __iomem *dma_base_addr; 571 int ret, i; 572 unsigned int irq; 573 struct moxart_chan *ch; 574 struct moxart_dmadev *mdc; 575 576 mdc = devm_kzalloc(dev, sizeof(*mdc), GFP_KERNEL); 577 if (!mdc) { 578 dev_err(dev, "can't allocate DMA container\n"); 579 return -ENOMEM; 580 } 581 582 irq = irq_of_parse_and_map(node, 0); 583 if (irq == NO_IRQ) { 584 dev_err(dev, "no IRQ resource\n"); 585 return -EINVAL; 586 } 587 588 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 589 dma_base_addr = devm_ioremap_resource(dev, res); 590 if (IS_ERR(dma_base_addr)) 591 return PTR_ERR(dma_base_addr); 592 593 dma_cap_zero(mdc->dma_slave.cap_mask); 594 dma_cap_set(DMA_SLAVE, mdc->dma_slave.cap_mask); 595 dma_cap_set(DMA_PRIVATE, mdc->dma_slave.cap_mask); 596 597 moxart_dma_init(&mdc->dma_slave, dev); 598 599 ch = &mdc->slave_chans[0]; 600 for (i = 0; i < APB_DMA_MAX_CHANNEL; i++, ch++) { 601 ch->ch_num = i; 602 ch->base = dma_base_addr + i * REG_OFF_CHAN_SIZE; 603 ch->allocated = 0; 604 605 ch->vc.desc_free = moxart_dma_desc_free; 606 vchan_init(&ch->vc, &mdc->dma_slave); 607 608 dev_dbg(dev, "%s: chs[%d]: ch->ch_num=%u ch->base=%p\n", 609 __func__, i, ch->ch_num, ch->base); 610 } 611 612 platform_set_drvdata(pdev, mdc); 613 614 ret = devm_request_irq(dev, irq, moxart_dma_interrupt, 0, 615 "moxart-dma-engine", mdc); 616 if (ret) { 617 dev_err(dev, "devm_request_irq failed\n"); 618 return ret; 619 } 620 621 ret = dma_async_device_register(&mdc->dma_slave); 622 if (ret) { 623 dev_err(dev, "dma_async_device_register failed\n"); 624 return ret; 625 } 626 627 ret = of_dma_controller_register(node, moxart_of_xlate, mdc); 628 if (ret) { 629 dev_err(dev, "of_dma_controller_register failed\n"); 630 dma_async_device_unregister(&mdc->dma_slave); 631 return ret; 632 } 633 634 dev_dbg(dev, "%s: IRQ=%u\n", __func__, irq); 635 636 return 0; 637 } 638 639 static int moxart_remove(struct platform_device *pdev) 640 { 641 struct moxart_dmadev *m = platform_get_drvdata(pdev); 642 643 dma_async_device_unregister(&m->dma_slave); 644 645 if (pdev->dev.of_node) 646 of_dma_controller_free(pdev->dev.of_node); 647 648 return 0; 649 } 650 651 static const struct of_device_id moxart_dma_match[] = { 652 { .compatible = "moxa,moxart-dma" }, 653 { } 654 }; 655 656 static struct platform_driver moxart_driver = { 657 .probe = moxart_probe, 658 .remove = moxart_remove, 659 .driver = { 660 .name = "moxart-dma-engine", 661 .of_match_table = moxart_dma_match, 662 }, 663 }; 664 665 static int moxart_init(void) 666 { 667 return platform_driver_register(&moxart_driver); 668 } 669 subsys_initcall(moxart_init); 670 671 static void __exit moxart_exit(void) 672 { 673 platform_driver_unregister(&moxart_driver); 674 } 675 module_exit(moxart_exit); 676 677 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>"); 678 MODULE_DESCRIPTION("MOXART DMA engine driver"); 679 MODULE_LICENSE("GPL v2"); 680