1 // SPDX-License-Identifier: GPL-2.0+ 2 // 3 // Freescale MXS SPI master driver 4 // 5 // Copyright 2012 DENX Software Engineering, GmbH. 6 // Copyright 2012 Freescale Semiconductor, Inc. 7 // Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. 8 // 9 // Rework and transition to new API by: 10 // Marek Vasut <marex@denx.de> 11 // 12 // Based on previous attempt by: 13 // Fabio Estevam <fabio.estevam@freescale.com> 14 // 15 // Based on code from U-Boot bootloader by: 16 // Marek Vasut <marex@denx.de> 17 // 18 // Based on spi-stmp.c, which is: 19 // Author: Dmitry Pervushin <dimka@embeddedalley.com> 20 21 #include <linux/kernel.h> 22 #include <linux/ioport.h> 23 #include <linux/of.h> 24 #include <linux/of_device.h> 25 #include <linux/of_gpio.h> 26 #include <linux/platform_device.h> 27 #include <linux/delay.h> 28 #include <linux/interrupt.h> 29 #include <linux/dma-mapping.h> 30 #include <linux/dmaengine.h> 31 #include <linux/highmem.h> 32 #include <linux/clk.h> 33 #include <linux/err.h> 34 #include <linux/completion.h> 35 #include <linux/gpio.h> 36 #include <linux/regulator/consumer.h> 37 #include <linux/pm_runtime.h> 38 #include <linux/module.h> 39 #include <linux/stmp_device.h> 40 #include <linux/spi/spi.h> 41 #include <linux/spi/mxs-spi.h> 42 #include <trace/events/spi.h> 43 44 #define DRIVER_NAME "mxs-spi" 45 46 /* Use 10S timeout for very long transfers, it should suffice. */ 47 #define SSP_TIMEOUT 10000 48 49 #define SG_MAXLEN 0xff00 50 51 /* 52 * Flags for txrx functions. More efficient that using an argument register for 53 * each one. 54 */ 55 #define TXRX_WRITE (1<<0) /* This is a write */ 56 #define TXRX_DEASSERT_CS (1<<1) /* De-assert CS at end of txrx */ 57 58 struct mxs_spi { 59 struct mxs_ssp ssp; 60 struct completion c; 61 unsigned int sck; /* Rate requested (vs actual) */ 62 }; 63 64 static int mxs_spi_setup_transfer(struct spi_device *dev, 65 const struct spi_transfer *t) 66 { 67 struct mxs_spi *spi = spi_master_get_devdata(dev->master); 68 struct mxs_ssp *ssp = &spi->ssp; 69 const unsigned int hz = min(dev->max_speed_hz, t->speed_hz); 70 71 if (hz == 0) { 72 dev_err(&dev->dev, "SPI clock rate of zero not allowed\n"); 73 return -EINVAL; 74 } 75 76 if (hz != spi->sck) { 77 mxs_ssp_set_clk_rate(ssp, hz); 78 /* 79 * Save requested rate, hz, rather than the actual rate, 80 * ssp->clk_rate. Otherwise we would set the rate every transfer 81 * when the actual rate is not quite the same as requested rate. 82 */ 83 spi->sck = hz; 84 /* 85 * Perhaps we should return an error if the actual clock is 86 * nowhere close to what was requested? 87 */ 88 } 89 90 writel(BM_SSP_CTRL0_LOCK_CS, 91 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); 92 93 writel(BF_SSP_CTRL1_SSP_MODE(BV_SSP_CTRL1_SSP_MODE__SPI) | 94 BF_SSP_CTRL1_WORD_LENGTH(BV_SSP_CTRL1_WORD_LENGTH__EIGHT_BITS) | 95 ((dev->mode & SPI_CPOL) ? BM_SSP_CTRL1_POLARITY : 0) | 96 ((dev->mode & SPI_CPHA) ? BM_SSP_CTRL1_PHASE : 0), 97 ssp->base + HW_SSP_CTRL1(ssp)); 98 99 writel(0x0, ssp->base + HW_SSP_CMD0); 100 writel(0x0, ssp->base + HW_SSP_CMD1); 101 102 return 0; 103 } 104 105 static u32 mxs_spi_cs_to_reg(unsigned cs) 106 { 107 u32 select = 0; 108 109 /* 110 * i.MX28 Datasheet: 17.10.1: HW_SSP_CTRL0 111 * 112 * The bits BM_SSP_CTRL0_WAIT_FOR_CMD and BM_SSP_CTRL0_WAIT_FOR_IRQ 113 * in HW_SSP_CTRL0 register do have multiple usage, please refer to 114 * the datasheet for further details. In SPI mode, they are used to 115 * toggle the chip-select lines (nCS pins). 116 */ 117 if (cs & 1) 118 select |= BM_SSP_CTRL0_WAIT_FOR_CMD; 119 if (cs & 2) 120 select |= BM_SSP_CTRL0_WAIT_FOR_IRQ; 121 122 return select; 123 } 124 125 static int mxs_ssp_wait(struct mxs_spi *spi, int offset, int mask, bool set) 126 { 127 const unsigned long timeout = jiffies + msecs_to_jiffies(SSP_TIMEOUT); 128 struct mxs_ssp *ssp = &spi->ssp; 129 u32 reg; 130 131 do { 132 reg = readl_relaxed(ssp->base + offset); 133 134 if (!set) 135 reg = ~reg; 136 137 reg &= mask; 138 139 if (reg == mask) 140 return 0; 141 } while (time_before(jiffies, timeout)); 142 143 return -ETIMEDOUT; 144 } 145 146 static void mxs_ssp_dma_irq_callback(void *param) 147 { 148 struct mxs_spi *spi = param; 149 150 complete(&spi->c); 151 } 152 153 static irqreturn_t mxs_ssp_irq_handler(int irq, void *dev_id) 154 { 155 struct mxs_ssp *ssp = dev_id; 156 157 dev_err(ssp->dev, "%s[%i] CTRL1=%08x STATUS=%08x\n", 158 __func__, __LINE__, 159 readl(ssp->base + HW_SSP_CTRL1(ssp)), 160 readl(ssp->base + HW_SSP_STATUS(ssp))); 161 return IRQ_HANDLED; 162 } 163 164 static int mxs_spi_txrx_dma(struct mxs_spi *spi, 165 unsigned char *buf, int len, 166 unsigned int flags) 167 { 168 struct mxs_ssp *ssp = &spi->ssp; 169 struct dma_async_tx_descriptor *desc = NULL; 170 const bool vmalloced_buf = is_vmalloc_addr(buf); 171 const int desc_len = vmalloced_buf ? PAGE_SIZE : SG_MAXLEN; 172 const int sgs = DIV_ROUND_UP(len, desc_len); 173 int sg_count; 174 int min, ret; 175 u32 ctrl0; 176 struct page *vm_page; 177 struct { 178 u32 pio[4]; 179 struct scatterlist sg; 180 } *dma_xfer; 181 182 if (!len) 183 return -EINVAL; 184 185 dma_xfer = kcalloc(sgs, sizeof(*dma_xfer), GFP_KERNEL); 186 if (!dma_xfer) 187 return -ENOMEM; 188 189 reinit_completion(&spi->c); 190 191 /* Chip select was already programmed into CTRL0 */ 192 ctrl0 = readl(ssp->base + HW_SSP_CTRL0); 193 ctrl0 &= ~(BM_SSP_CTRL0_XFER_COUNT | BM_SSP_CTRL0_IGNORE_CRC | 194 BM_SSP_CTRL0_READ); 195 ctrl0 |= BM_SSP_CTRL0_DATA_XFER; 196 197 if (!(flags & TXRX_WRITE)) 198 ctrl0 |= BM_SSP_CTRL0_READ; 199 200 /* Queue the DMA data transfer. */ 201 for (sg_count = 0; sg_count < sgs; sg_count++) { 202 /* Prepare the transfer descriptor. */ 203 min = min(len, desc_len); 204 205 /* 206 * De-assert CS on last segment if flag is set (i.e., no more 207 * transfers will follow) 208 */ 209 if ((sg_count + 1 == sgs) && (flags & TXRX_DEASSERT_CS)) 210 ctrl0 |= BM_SSP_CTRL0_IGNORE_CRC; 211 212 if (ssp->devid == IMX23_SSP) { 213 ctrl0 &= ~BM_SSP_CTRL0_XFER_COUNT; 214 ctrl0 |= min; 215 } 216 217 dma_xfer[sg_count].pio[0] = ctrl0; 218 dma_xfer[sg_count].pio[3] = min; 219 220 if (vmalloced_buf) { 221 vm_page = vmalloc_to_page(buf); 222 if (!vm_page) { 223 ret = -ENOMEM; 224 goto err_vmalloc; 225 } 226 227 sg_init_table(&dma_xfer[sg_count].sg, 1); 228 sg_set_page(&dma_xfer[sg_count].sg, vm_page, 229 min, offset_in_page(buf)); 230 } else { 231 sg_init_one(&dma_xfer[sg_count].sg, buf, min); 232 } 233 234 ret = dma_map_sg(ssp->dev, &dma_xfer[sg_count].sg, 1, 235 (flags & TXRX_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE); 236 237 len -= min; 238 buf += min; 239 240 /* Queue the PIO register write transfer. */ 241 desc = dmaengine_prep_slave_sg(ssp->dmach, 242 (struct scatterlist *)dma_xfer[sg_count].pio, 243 (ssp->devid == IMX23_SSP) ? 1 : 4, 244 DMA_TRANS_NONE, 245 sg_count ? DMA_PREP_INTERRUPT : 0); 246 if (!desc) { 247 dev_err(ssp->dev, 248 "Failed to get PIO reg. write descriptor.\n"); 249 ret = -EINVAL; 250 goto err_mapped; 251 } 252 253 desc = dmaengine_prep_slave_sg(ssp->dmach, 254 &dma_xfer[sg_count].sg, 1, 255 (flags & TXRX_WRITE) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM, 256 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 257 258 if (!desc) { 259 dev_err(ssp->dev, 260 "Failed to get DMA data write descriptor.\n"); 261 ret = -EINVAL; 262 goto err_mapped; 263 } 264 } 265 266 /* 267 * The last descriptor must have this callback, 268 * to finish the DMA transaction. 269 */ 270 desc->callback = mxs_ssp_dma_irq_callback; 271 desc->callback_param = spi; 272 273 /* Start the transfer. */ 274 dmaengine_submit(desc); 275 dma_async_issue_pending(ssp->dmach); 276 277 if (!wait_for_completion_timeout(&spi->c, 278 msecs_to_jiffies(SSP_TIMEOUT))) { 279 dev_err(ssp->dev, "DMA transfer timeout\n"); 280 ret = -ETIMEDOUT; 281 dmaengine_terminate_all(ssp->dmach); 282 goto err_vmalloc; 283 } 284 285 ret = 0; 286 287 err_vmalloc: 288 while (--sg_count >= 0) { 289 err_mapped: 290 dma_unmap_sg(ssp->dev, &dma_xfer[sg_count].sg, 1, 291 (flags & TXRX_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE); 292 } 293 294 kfree(dma_xfer); 295 296 return ret; 297 } 298 299 static int mxs_spi_txrx_pio(struct mxs_spi *spi, 300 unsigned char *buf, int len, 301 unsigned int flags) 302 { 303 struct mxs_ssp *ssp = &spi->ssp; 304 305 writel(BM_SSP_CTRL0_IGNORE_CRC, 306 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); 307 308 while (len--) { 309 if (len == 0 && (flags & TXRX_DEASSERT_CS)) 310 writel(BM_SSP_CTRL0_IGNORE_CRC, 311 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); 312 313 if (ssp->devid == IMX23_SSP) { 314 writel(BM_SSP_CTRL0_XFER_COUNT, 315 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); 316 writel(1, 317 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); 318 } else { 319 writel(1, ssp->base + HW_SSP_XFER_SIZE); 320 } 321 322 if (flags & TXRX_WRITE) 323 writel(BM_SSP_CTRL0_READ, 324 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); 325 else 326 writel(BM_SSP_CTRL0_READ, 327 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); 328 329 writel(BM_SSP_CTRL0_RUN, 330 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); 331 332 if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 1)) 333 return -ETIMEDOUT; 334 335 if (flags & TXRX_WRITE) 336 writel(*buf, ssp->base + HW_SSP_DATA(ssp)); 337 338 writel(BM_SSP_CTRL0_DATA_XFER, 339 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); 340 341 if (!(flags & TXRX_WRITE)) { 342 if (mxs_ssp_wait(spi, HW_SSP_STATUS(ssp), 343 BM_SSP_STATUS_FIFO_EMPTY, 0)) 344 return -ETIMEDOUT; 345 346 *buf = (readl(ssp->base + HW_SSP_DATA(ssp)) & 0xff); 347 } 348 349 if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 0)) 350 return -ETIMEDOUT; 351 352 buf++; 353 } 354 355 if (len <= 0) 356 return 0; 357 358 return -ETIMEDOUT; 359 } 360 361 static int mxs_spi_transfer_one(struct spi_master *master, 362 struct spi_message *m) 363 { 364 struct mxs_spi *spi = spi_master_get_devdata(master); 365 struct mxs_ssp *ssp = &spi->ssp; 366 struct spi_transfer *t; 367 unsigned int flag; 368 int status = 0; 369 370 /* Program CS register bits here, it will be used for all transfers. */ 371 writel(BM_SSP_CTRL0_WAIT_FOR_CMD | BM_SSP_CTRL0_WAIT_FOR_IRQ, 372 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); 373 writel(mxs_spi_cs_to_reg(m->spi->chip_select), 374 ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); 375 376 list_for_each_entry(t, &m->transfers, transfer_list) { 377 378 trace_spi_transfer_start(m, t); 379 380 status = mxs_spi_setup_transfer(m->spi, t); 381 if (status) 382 break; 383 384 /* De-assert on last transfer, inverted by cs_change flag */ 385 flag = (&t->transfer_list == m->transfers.prev) ^ t->cs_change ? 386 TXRX_DEASSERT_CS : 0; 387 388 /* 389 * Small blocks can be transfered via PIO. 390 * Measured by empiric means: 391 * 392 * dd if=/dev/mtdblock0 of=/dev/null bs=1024k count=1 393 * 394 * DMA only: 2.164808 seconds, 473.0KB/s 395 * Combined: 1.676276 seconds, 610.9KB/s 396 */ 397 if (t->len < 32) { 398 writel(BM_SSP_CTRL1_DMA_ENABLE, 399 ssp->base + HW_SSP_CTRL1(ssp) + 400 STMP_OFFSET_REG_CLR); 401 402 if (t->tx_buf) 403 status = mxs_spi_txrx_pio(spi, 404 (void *)t->tx_buf, 405 t->len, flag | TXRX_WRITE); 406 if (t->rx_buf) 407 status = mxs_spi_txrx_pio(spi, 408 t->rx_buf, t->len, 409 flag); 410 } else { 411 writel(BM_SSP_CTRL1_DMA_ENABLE, 412 ssp->base + HW_SSP_CTRL1(ssp) + 413 STMP_OFFSET_REG_SET); 414 415 if (t->tx_buf) 416 status = mxs_spi_txrx_dma(spi, 417 (void *)t->tx_buf, t->len, 418 flag | TXRX_WRITE); 419 if (t->rx_buf) 420 status = mxs_spi_txrx_dma(spi, 421 t->rx_buf, t->len, 422 flag); 423 } 424 425 trace_spi_transfer_stop(m, t); 426 427 if (status) { 428 stmp_reset_block(ssp->base); 429 break; 430 } 431 432 m->actual_length += t->len; 433 } 434 435 m->status = status; 436 spi_finalize_current_message(master); 437 438 return status; 439 } 440 441 static int mxs_spi_runtime_suspend(struct device *dev) 442 { 443 struct spi_master *master = dev_get_drvdata(dev); 444 struct mxs_spi *spi = spi_master_get_devdata(master); 445 struct mxs_ssp *ssp = &spi->ssp; 446 int ret; 447 448 clk_disable_unprepare(ssp->clk); 449 450 ret = pinctrl_pm_select_idle_state(dev); 451 if (ret) { 452 int ret2 = clk_prepare_enable(ssp->clk); 453 454 if (ret2) 455 dev_warn(dev, "Failed to reenable clock after failing pinctrl request (pinctrl: %d, clk: %d)\n", 456 ret, ret2); 457 } 458 459 return ret; 460 } 461 462 static int mxs_spi_runtime_resume(struct device *dev) 463 { 464 struct spi_master *master = dev_get_drvdata(dev); 465 struct mxs_spi *spi = spi_master_get_devdata(master); 466 struct mxs_ssp *ssp = &spi->ssp; 467 int ret; 468 469 ret = pinctrl_pm_select_default_state(dev); 470 if (ret) 471 return ret; 472 473 ret = clk_prepare_enable(ssp->clk); 474 if (ret) 475 pinctrl_pm_select_idle_state(dev); 476 477 return ret; 478 } 479 480 static int __maybe_unused mxs_spi_suspend(struct device *dev) 481 { 482 struct spi_master *master = dev_get_drvdata(dev); 483 int ret; 484 485 ret = spi_master_suspend(master); 486 if (ret) 487 return ret; 488 489 if (!pm_runtime_suspended(dev)) 490 return mxs_spi_runtime_suspend(dev); 491 else 492 return 0; 493 } 494 495 static int __maybe_unused mxs_spi_resume(struct device *dev) 496 { 497 struct spi_master *master = dev_get_drvdata(dev); 498 int ret; 499 500 if (!pm_runtime_suspended(dev)) 501 ret = mxs_spi_runtime_resume(dev); 502 else 503 ret = 0; 504 if (ret) 505 return ret; 506 507 ret = spi_master_resume(master); 508 if (ret < 0 && !pm_runtime_suspended(dev)) 509 mxs_spi_runtime_suspend(dev); 510 511 return ret; 512 } 513 514 static const struct dev_pm_ops mxs_spi_pm = { 515 SET_RUNTIME_PM_OPS(mxs_spi_runtime_suspend, 516 mxs_spi_runtime_resume, NULL) 517 SET_SYSTEM_SLEEP_PM_OPS(mxs_spi_suspend, mxs_spi_resume) 518 }; 519 520 static const struct of_device_id mxs_spi_dt_ids[] = { 521 { .compatible = "fsl,imx23-spi", .data = (void *) IMX23_SSP, }, 522 { .compatible = "fsl,imx28-spi", .data = (void *) IMX28_SSP, }, 523 { /* sentinel */ } 524 }; 525 MODULE_DEVICE_TABLE(of, mxs_spi_dt_ids); 526 527 static int mxs_spi_probe(struct platform_device *pdev) 528 { 529 const struct of_device_id *of_id = 530 of_match_device(mxs_spi_dt_ids, &pdev->dev); 531 struct device_node *np = pdev->dev.of_node; 532 struct spi_master *master; 533 struct mxs_spi *spi; 534 struct mxs_ssp *ssp; 535 struct clk *clk; 536 void __iomem *base; 537 int devid, clk_freq; 538 int ret = 0, irq_err; 539 540 /* 541 * Default clock speed for the SPI core. 160MHz seems to 542 * work reasonably well with most SPI flashes, so use this 543 * as a default. Override with "clock-frequency" DT prop. 544 */ 545 const int clk_freq_default = 160000000; 546 547 irq_err = platform_get_irq(pdev, 0); 548 if (irq_err < 0) 549 return irq_err; 550 551 base = devm_platform_ioremap_resource(pdev, 0); 552 if (IS_ERR(base)) 553 return PTR_ERR(base); 554 555 clk = devm_clk_get(&pdev->dev, NULL); 556 if (IS_ERR(clk)) 557 return PTR_ERR(clk); 558 559 devid = (enum mxs_ssp_id) of_id->data; 560 ret = of_property_read_u32(np, "clock-frequency", 561 &clk_freq); 562 if (ret) 563 clk_freq = clk_freq_default; 564 565 master = spi_alloc_master(&pdev->dev, sizeof(*spi)); 566 if (!master) 567 return -ENOMEM; 568 569 platform_set_drvdata(pdev, master); 570 571 master->transfer_one_message = mxs_spi_transfer_one; 572 master->bits_per_word_mask = SPI_BPW_MASK(8); 573 master->mode_bits = SPI_CPOL | SPI_CPHA; 574 master->num_chipselect = 3; 575 master->dev.of_node = np; 576 master->flags = SPI_MASTER_HALF_DUPLEX; 577 master->auto_runtime_pm = true; 578 579 spi = spi_master_get_devdata(master); 580 ssp = &spi->ssp; 581 ssp->dev = &pdev->dev; 582 ssp->clk = clk; 583 ssp->base = base; 584 ssp->devid = devid; 585 586 init_completion(&spi->c); 587 588 ret = devm_request_irq(&pdev->dev, irq_err, mxs_ssp_irq_handler, 0, 589 dev_name(&pdev->dev), ssp); 590 if (ret) 591 goto out_master_free; 592 593 ssp->dmach = dma_request_slave_channel(&pdev->dev, "rx-tx"); 594 if (!ssp->dmach) { 595 dev_err(ssp->dev, "Failed to request DMA\n"); 596 ret = -ENODEV; 597 goto out_master_free; 598 } 599 600 pm_runtime_enable(ssp->dev); 601 if (!pm_runtime_enabled(ssp->dev)) { 602 ret = mxs_spi_runtime_resume(ssp->dev); 603 if (ret < 0) { 604 dev_err(ssp->dev, "runtime resume failed\n"); 605 goto out_dma_release; 606 } 607 } 608 609 ret = pm_runtime_get_sync(ssp->dev); 610 if (ret < 0) { 611 dev_err(ssp->dev, "runtime_get_sync failed\n"); 612 goto out_pm_runtime_disable; 613 } 614 615 clk_set_rate(ssp->clk, clk_freq); 616 617 ret = stmp_reset_block(ssp->base); 618 if (ret) 619 goto out_pm_runtime_put; 620 621 ret = devm_spi_register_master(&pdev->dev, master); 622 if (ret) { 623 dev_err(&pdev->dev, "Cannot register SPI master, %d\n", ret); 624 goto out_pm_runtime_put; 625 } 626 627 pm_runtime_put(ssp->dev); 628 629 return 0; 630 631 out_pm_runtime_put: 632 pm_runtime_put(ssp->dev); 633 out_pm_runtime_disable: 634 pm_runtime_disable(ssp->dev); 635 out_dma_release: 636 dma_release_channel(ssp->dmach); 637 out_master_free: 638 spi_master_put(master); 639 return ret; 640 } 641 642 static int mxs_spi_remove(struct platform_device *pdev) 643 { 644 struct spi_master *master; 645 struct mxs_spi *spi; 646 struct mxs_ssp *ssp; 647 648 master = platform_get_drvdata(pdev); 649 spi = spi_master_get_devdata(master); 650 ssp = &spi->ssp; 651 652 pm_runtime_disable(&pdev->dev); 653 if (!pm_runtime_status_suspended(&pdev->dev)) 654 mxs_spi_runtime_suspend(&pdev->dev); 655 656 dma_release_channel(ssp->dmach); 657 658 return 0; 659 } 660 661 static struct platform_driver mxs_spi_driver = { 662 .probe = mxs_spi_probe, 663 .remove = mxs_spi_remove, 664 .driver = { 665 .name = DRIVER_NAME, 666 .of_match_table = mxs_spi_dt_ids, 667 .pm = &mxs_spi_pm, 668 }, 669 }; 670 671 module_platform_driver(mxs_spi_driver); 672 673 MODULE_AUTHOR("Marek Vasut <marex@denx.de>"); 674 MODULE_DESCRIPTION("MXS SPI master driver"); 675 MODULE_LICENSE("GPL"); 676 MODULE_ALIAS("platform:mxs-spi"); 677