1 /* 2 * MOXA ART MMC host driver. 3 * 4 * Copyright (C) 2014 Jonas Jensen 5 * 6 * Jonas Jensen <jonas.jensen@gmail.com> 7 * 8 * Based on code from 9 * Moxa Technologies Co., Ltd. <www.moxa.com> 10 * 11 * This file is licensed under the terms of the GNU General Public 12 * License version 2. This program is licensed "as is" without any 13 * warranty of any kind, whether express or implied. 14 */ 15 16 #include <linux/module.h> 17 #include <linux/init.h> 18 #include <linux/platform_device.h> 19 #include <linux/delay.h> 20 #include <linux/errno.h> 21 #include <linux/interrupt.h> 22 #include <linux/blkdev.h> 23 #include <linux/dma-mapping.h> 24 #include <linux/dmaengine.h> 25 #include <linux/mmc/host.h> 26 #include <linux/mmc/sd.h> 27 #include <linux/sched.h> 28 #include <linux/io.h> 29 #include <linux/of_address.h> 30 #include <linux/of_irq.h> 31 #include <linux/clk.h> 32 #include <linux/bitops.h> 33 #include <linux/of_dma.h> 34 #include <linux/spinlock.h> 35 36 #define REG_COMMAND 0 37 #define REG_ARGUMENT 4 38 #define REG_RESPONSE0 8 39 #define REG_RESPONSE1 12 40 #define REG_RESPONSE2 16 41 #define REG_RESPONSE3 20 42 #define REG_RESPONSE_COMMAND 24 43 #define REG_DATA_CONTROL 28 44 #define REG_DATA_TIMER 32 45 #define REG_DATA_LENGTH 36 46 #define REG_STATUS 40 47 #define REG_CLEAR 44 48 #define REG_INTERRUPT_MASK 48 49 #define REG_POWER_CONTROL 52 50 #define REG_CLOCK_CONTROL 56 51 #define REG_BUS_WIDTH 60 52 #define REG_DATA_WINDOW 64 53 #define REG_FEATURE 68 54 #define REG_REVISION 72 55 56 /* REG_COMMAND */ 57 #define CMD_SDC_RESET BIT(10) 58 #define CMD_EN BIT(9) 59 #define CMD_APP_CMD BIT(8) 60 #define CMD_LONG_RSP BIT(7) 61 #define CMD_NEED_RSP BIT(6) 62 #define CMD_IDX_MASK 0x3f 63 64 /* REG_RESPONSE_COMMAND */ 65 #define RSP_CMD_APP BIT(6) 66 #define RSP_CMD_IDX_MASK 0x3f 67 68 /* REG_DATA_CONTROL */ 69 #define DCR_DATA_FIFO_RESET BIT(8) 70 #define DCR_DATA_THRES BIT(7) 71 #define DCR_DATA_EN BIT(6) 72 #define DCR_DMA_EN BIT(5) 73 #define DCR_DATA_WRITE BIT(4) 74 #define DCR_BLK_SIZE 0x0f 75 76 /* REG_DATA_LENGTH */ 77 #define DATA_LEN_MASK 0xffffff 78 79 /* REG_STATUS */ 80 #define WRITE_PROT BIT(12) 81 #define CARD_DETECT BIT(11) 82 /* 1-10 below can be sent to either registers, interrupt or clear. */ 83 #define CARD_CHANGE BIT(10) 84 #define FIFO_ORUN BIT(9) 85 #define FIFO_URUN BIT(8) 86 #define DATA_END BIT(7) 87 #define CMD_SENT BIT(6) 88 #define DATA_CRC_OK BIT(5) 89 #define RSP_CRC_OK BIT(4) 90 #define DATA_TIMEOUT BIT(3) 91 #define RSP_TIMEOUT BIT(2) 92 #define DATA_CRC_FAIL BIT(1) 93 #define RSP_CRC_FAIL BIT(0) 94 95 #define MASK_RSP (RSP_TIMEOUT | RSP_CRC_FAIL | \ 96 RSP_CRC_OK | CARD_DETECT | CMD_SENT) 97 98 #define MASK_DATA (DATA_CRC_OK | DATA_END | \ 99 DATA_CRC_FAIL | DATA_TIMEOUT) 100 101 #define MASK_INTR_PIO (FIFO_URUN | FIFO_ORUN | CARD_CHANGE) 102 103 /* REG_POWER_CONTROL */ 104 #define SD_POWER_ON BIT(4) 105 #define SD_POWER_MASK 0x0f 106 107 /* REG_CLOCK_CONTROL */ 108 #define CLK_HISPD BIT(9) 109 #define CLK_OFF BIT(8) 110 #define CLK_SD BIT(7) 111 #define CLK_DIV_MASK 0x7f 112 113 /* REG_BUS_WIDTH */ 114 #define BUS_WIDTH_4_SUPPORT BIT(3) 115 #define BUS_WIDTH_4 BIT(2) 116 #define BUS_WIDTH_1 BIT(0) 117 118 #define MMC_VDD_360 23 119 #define MIN_POWER (MMC_VDD_360 - SD_POWER_MASK) 120 #define MAX_RETRIES 500000 121 122 struct moxart_host { 123 spinlock_t lock; 124 125 void __iomem *base; 126 127 phys_addr_t reg_phys; 128 129 struct dma_chan *dma_chan_tx; 130 struct dma_chan *dma_chan_rx; 131 struct dma_async_tx_descriptor *tx_desc; 132 struct mmc_host *mmc; 133 struct mmc_request *mrq; 134 struct scatterlist *cur_sg; 135 struct completion dma_complete; 136 struct completion pio_complete; 137 138 u32 num_sg; 139 u32 data_remain; 140 u32 data_len; 141 u32 fifo_width; 142 u32 timeout; 143 u32 rate; 144 145 long sysclk; 146 147 bool have_dma; 148 bool is_removed; 149 }; 150 151 static inline void moxart_init_sg(struct moxart_host *host, 152 struct mmc_data *data) 153 { 154 host->cur_sg = data->sg; 155 host->num_sg = data->sg_len; 156 host->data_remain = host->cur_sg->length; 157 158 if (host->data_remain > host->data_len) 159 host->data_remain = host->data_len; 160 } 161 162 static inline int moxart_next_sg(struct moxart_host *host) 163 { 164 int remain; 165 struct mmc_data *data = host->mrq->cmd->data; 166 167 host->cur_sg++; 168 host->num_sg--; 169 170 if (host->num_sg > 0) { 171 host->data_remain = host->cur_sg->length; 172 remain = host->data_len - data->bytes_xfered; 173 if (remain > 0 && remain < host->data_remain) 174 host->data_remain = remain; 175 } 176 177 return host->num_sg; 178 } 179 180 static int moxart_wait_for_status(struct moxart_host *host, 181 u32 mask, u32 *status) 182 { 183 int ret = -ETIMEDOUT; 184 u32 i; 185 186 for (i = 0; i < MAX_RETRIES; i++) { 187 *status = readl(host->base + REG_STATUS); 188 if (!(*status & mask)) { 189 udelay(5); 190 continue; 191 } 192 writel(*status & mask, host->base + REG_CLEAR); 193 ret = 0; 194 break; 195 } 196 197 if (ret) 198 dev_err(mmc_dev(host->mmc), "timed out waiting for status\n"); 199 200 return ret; 201 } 202 203 204 static void moxart_send_command(struct moxart_host *host, 205 struct mmc_command *cmd) 206 { 207 u32 status, cmdctrl; 208 209 writel(RSP_TIMEOUT | RSP_CRC_OK | 210 RSP_CRC_FAIL | CMD_SENT, host->base + REG_CLEAR); 211 writel(cmd->arg, host->base + REG_ARGUMENT); 212 213 cmdctrl = cmd->opcode & CMD_IDX_MASK; 214 if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND || 215 cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS || 216 cmdctrl == SD_APP_SEND_NUM_WR_BLKS) 217 cmdctrl |= CMD_APP_CMD; 218 219 if (cmd->flags & MMC_RSP_PRESENT) 220 cmdctrl |= CMD_NEED_RSP; 221 222 if (cmd->flags & MMC_RSP_136) 223 cmdctrl |= CMD_LONG_RSP; 224 225 writel(cmdctrl | CMD_EN, host->base + REG_COMMAND); 226 227 if (moxart_wait_for_status(host, MASK_RSP, &status) == -ETIMEDOUT) 228 cmd->error = -ETIMEDOUT; 229 230 if (status & RSP_TIMEOUT) { 231 cmd->error = -ETIMEDOUT; 232 return; 233 } 234 if (status & RSP_CRC_FAIL) { 235 cmd->error = -EIO; 236 return; 237 } 238 if (status & RSP_CRC_OK) { 239 if (cmd->flags & MMC_RSP_136) { 240 cmd->resp[3] = readl(host->base + REG_RESPONSE0); 241 cmd->resp[2] = readl(host->base + REG_RESPONSE1); 242 cmd->resp[1] = readl(host->base + REG_RESPONSE2); 243 cmd->resp[0] = readl(host->base + REG_RESPONSE3); 244 } else { 245 cmd->resp[0] = readl(host->base + REG_RESPONSE0); 246 } 247 } 248 } 249 250 static void moxart_dma_complete(void *param) 251 { 252 struct moxart_host *host = param; 253 254 complete(&host->dma_complete); 255 } 256 257 static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host) 258 { 259 u32 len, dir_slave; 260 struct dma_async_tx_descriptor *desc = NULL; 261 struct dma_chan *dma_chan; 262 263 if (host->data_len == data->bytes_xfered) 264 return; 265 266 if (data->flags & MMC_DATA_WRITE) { 267 dma_chan = host->dma_chan_tx; 268 dir_slave = DMA_MEM_TO_DEV; 269 } else { 270 dma_chan = host->dma_chan_rx; 271 dir_slave = DMA_DEV_TO_MEM; 272 } 273 274 len = dma_map_sg(dma_chan->device->dev, data->sg, 275 data->sg_len, mmc_get_dma_dir(data)); 276 277 if (len > 0) { 278 desc = dmaengine_prep_slave_sg(dma_chan, data->sg, 279 len, dir_slave, 280 DMA_PREP_INTERRUPT | 281 DMA_CTRL_ACK); 282 } else { 283 dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n"); 284 } 285 286 if (desc) { 287 host->tx_desc = desc; 288 desc->callback = moxart_dma_complete; 289 desc->callback_param = host; 290 dmaengine_submit(desc); 291 dma_async_issue_pending(dma_chan); 292 } 293 294 data->bytes_xfered += host->data_remain; 295 296 wait_for_completion_interruptible_timeout(&host->dma_complete, 297 host->timeout); 298 299 dma_unmap_sg(dma_chan->device->dev, 300 data->sg, data->sg_len, 301 mmc_get_dma_dir(data)); 302 } 303 304 305 static void moxart_transfer_pio(struct moxart_host *host) 306 { 307 struct mmc_data *data = host->mrq->cmd->data; 308 u32 *sgp, len = 0, remain, status; 309 310 if (host->data_len == data->bytes_xfered) 311 return; 312 313 sgp = sg_virt(host->cur_sg); 314 remain = host->data_remain; 315 316 if (data->flags & MMC_DATA_WRITE) { 317 while (remain > 0) { 318 if (moxart_wait_for_status(host, FIFO_URUN, &status) 319 == -ETIMEDOUT) { 320 data->error = -ETIMEDOUT; 321 complete(&host->pio_complete); 322 return; 323 } 324 for (len = 0; len < remain && len < host->fifo_width;) { 325 iowrite32(*sgp, host->base + REG_DATA_WINDOW); 326 sgp++; 327 len += 4; 328 } 329 remain -= len; 330 } 331 332 } else { 333 while (remain > 0) { 334 if (moxart_wait_for_status(host, FIFO_ORUN, &status) 335 == -ETIMEDOUT) { 336 data->error = -ETIMEDOUT; 337 complete(&host->pio_complete); 338 return; 339 } 340 for (len = 0; len < remain && len < host->fifo_width;) { 341 /* SCR data must be read in big endian. */ 342 if (data->mrq->cmd->opcode == SD_APP_SEND_SCR) 343 *sgp = ioread32be(host->base + 344 REG_DATA_WINDOW); 345 else 346 *sgp = ioread32(host->base + 347 REG_DATA_WINDOW); 348 sgp++; 349 len += 4; 350 } 351 remain -= len; 352 } 353 } 354 355 data->bytes_xfered += host->data_remain - remain; 356 host->data_remain = remain; 357 358 if (host->data_len != data->bytes_xfered) 359 moxart_next_sg(host); 360 else 361 complete(&host->pio_complete); 362 } 363 364 static void moxart_prepare_data(struct moxart_host *host) 365 { 366 struct mmc_data *data = host->mrq->cmd->data; 367 u32 datactrl; 368 int blksz_bits; 369 370 if (!data) 371 return; 372 373 host->data_len = data->blocks * data->blksz; 374 blksz_bits = ffs(data->blksz) - 1; 375 BUG_ON(1 << blksz_bits != data->blksz); 376 377 moxart_init_sg(host, data); 378 379 datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE); 380 381 if (data->flags & MMC_DATA_WRITE) 382 datactrl |= DCR_DATA_WRITE; 383 384 if ((host->data_len > host->fifo_width) && host->have_dma) 385 datactrl |= DCR_DMA_EN; 386 387 writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL); 388 writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR); 389 writel(host->rate, host->base + REG_DATA_TIMER); 390 writel(host->data_len, host->base + REG_DATA_LENGTH); 391 writel(datactrl, host->base + REG_DATA_CONTROL); 392 } 393 394 static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq) 395 { 396 struct moxart_host *host = mmc_priv(mmc); 397 unsigned long flags; 398 u32 status; 399 400 spin_lock_irqsave(&host->lock, flags); 401 402 init_completion(&host->dma_complete); 403 init_completion(&host->pio_complete); 404 405 host->mrq = mrq; 406 407 if (readl(host->base + REG_STATUS) & CARD_DETECT) { 408 mrq->cmd->error = -ETIMEDOUT; 409 goto request_done; 410 } 411 412 moxart_prepare_data(host); 413 moxart_send_command(host, host->mrq->cmd); 414 415 if (mrq->cmd->data) { 416 if ((host->data_len > host->fifo_width) && host->have_dma) { 417 418 writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK); 419 420 spin_unlock_irqrestore(&host->lock, flags); 421 422 moxart_transfer_dma(mrq->cmd->data, host); 423 424 spin_lock_irqsave(&host->lock, flags); 425 } else { 426 427 writel(MASK_INTR_PIO, host->base + REG_INTERRUPT_MASK); 428 429 spin_unlock_irqrestore(&host->lock, flags); 430 431 /* PIO transfers start from interrupt. */ 432 wait_for_completion_interruptible_timeout(&host->pio_complete, 433 host->timeout); 434 435 spin_lock_irqsave(&host->lock, flags); 436 } 437 438 if (host->is_removed) { 439 dev_err(mmc_dev(host->mmc), "card removed\n"); 440 mrq->cmd->error = -ETIMEDOUT; 441 goto request_done; 442 } 443 444 if (moxart_wait_for_status(host, MASK_DATA, &status) 445 == -ETIMEDOUT) { 446 mrq->cmd->data->error = -ETIMEDOUT; 447 goto request_done; 448 } 449 450 if (status & DATA_CRC_FAIL) 451 mrq->cmd->data->error = -ETIMEDOUT; 452 453 if (mrq->cmd->data->stop) 454 moxart_send_command(host, mrq->cmd->data->stop); 455 } 456 457 request_done: 458 spin_unlock_irqrestore(&host->lock, flags); 459 mmc_request_done(host->mmc, mrq); 460 } 461 462 static irqreturn_t moxart_irq(int irq, void *devid) 463 { 464 struct moxart_host *host = (struct moxart_host *)devid; 465 u32 status; 466 467 spin_lock(&host->lock); 468 469 status = readl(host->base + REG_STATUS); 470 if (status & CARD_CHANGE) { 471 host->is_removed = status & CARD_DETECT; 472 if (host->is_removed && host->have_dma) { 473 dmaengine_terminate_all(host->dma_chan_tx); 474 dmaengine_terminate_all(host->dma_chan_rx); 475 } 476 host->mrq = NULL; 477 writel(MASK_INTR_PIO, host->base + REG_CLEAR); 478 writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK); 479 mmc_detect_change(host->mmc, 0); 480 } 481 if (status & (FIFO_ORUN | FIFO_URUN) && host->mrq) 482 moxart_transfer_pio(host); 483 484 spin_unlock(&host->lock); 485 486 return IRQ_HANDLED; 487 } 488 489 static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) 490 { 491 struct moxart_host *host = mmc_priv(mmc); 492 unsigned long flags; 493 u8 power, div; 494 u32 ctrl; 495 496 spin_lock_irqsave(&host->lock, flags); 497 498 if (ios->clock) { 499 for (div = 0; div < CLK_DIV_MASK; ++div) { 500 if (ios->clock >= host->sysclk / (2 * (div + 1))) 501 break; 502 } 503 ctrl = CLK_SD | div; 504 host->rate = host->sysclk / (2 * (div + 1)); 505 if (host->rate > host->sysclk) 506 ctrl |= CLK_HISPD; 507 writel(ctrl, host->base + REG_CLOCK_CONTROL); 508 } 509 510 if (ios->power_mode == MMC_POWER_OFF) { 511 writel(readl(host->base + REG_POWER_CONTROL) & ~SD_POWER_ON, 512 host->base + REG_POWER_CONTROL); 513 } else { 514 if (ios->vdd < MIN_POWER) 515 power = 0; 516 else 517 power = ios->vdd - MIN_POWER; 518 519 writel(SD_POWER_ON | (u32) power, 520 host->base + REG_POWER_CONTROL); 521 } 522 523 switch (ios->bus_width) { 524 case MMC_BUS_WIDTH_4: 525 writel(BUS_WIDTH_4, host->base + REG_BUS_WIDTH); 526 break; 527 default: 528 writel(BUS_WIDTH_1, host->base + REG_BUS_WIDTH); 529 break; 530 } 531 532 spin_unlock_irqrestore(&host->lock, flags); 533 } 534 535 536 static int moxart_get_ro(struct mmc_host *mmc) 537 { 538 struct moxart_host *host = mmc_priv(mmc); 539 540 return !!(readl(host->base + REG_STATUS) & WRITE_PROT); 541 } 542 543 static const struct mmc_host_ops moxart_ops = { 544 .request = moxart_request, 545 .set_ios = moxart_set_ios, 546 .get_ro = moxart_get_ro, 547 }; 548 549 static int moxart_probe(struct platform_device *pdev) 550 { 551 struct device *dev = &pdev->dev; 552 struct device_node *node = dev->of_node; 553 struct resource res_mmc; 554 struct mmc_host *mmc; 555 struct moxart_host *host = NULL; 556 struct dma_slave_config cfg; 557 struct clk *clk; 558 void __iomem *reg_mmc; 559 int irq, ret; 560 u32 i; 561 562 mmc = mmc_alloc_host(sizeof(struct moxart_host), dev); 563 if (!mmc) { 564 dev_err(dev, "mmc_alloc_host failed\n"); 565 ret = -ENOMEM; 566 goto out_mmc; 567 } 568 569 ret = of_address_to_resource(node, 0, &res_mmc); 570 if (ret) { 571 dev_err(dev, "of_address_to_resource failed\n"); 572 goto out_mmc; 573 } 574 575 irq = irq_of_parse_and_map(node, 0); 576 if (irq <= 0) { 577 dev_err(dev, "irq_of_parse_and_map failed\n"); 578 ret = -EINVAL; 579 goto out_mmc; 580 } 581 582 clk = devm_clk_get(dev, NULL); 583 if (IS_ERR(clk)) { 584 ret = PTR_ERR(clk); 585 goto out_mmc; 586 } 587 588 reg_mmc = devm_ioremap_resource(dev, &res_mmc); 589 if (IS_ERR(reg_mmc)) { 590 ret = PTR_ERR(reg_mmc); 591 goto out_mmc; 592 } 593 594 ret = mmc_of_parse(mmc); 595 if (ret) 596 goto out_mmc; 597 598 host = mmc_priv(mmc); 599 host->mmc = mmc; 600 host->base = reg_mmc; 601 host->reg_phys = res_mmc.start; 602 host->timeout = msecs_to_jiffies(1000); 603 host->sysclk = clk_get_rate(clk); 604 host->fifo_width = readl(host->base + REG_FEATURE) << 2; 605 host->dma_chan_tx = dma_request_chan(dev, "tx"); 606 host->dma_chan_rx = dma_request_chan(dev, "rx"); 607 608 spin_lock_init(&host->lock); 609 610 mmc->ops = &moxart_ops; 611 mmc->f_max = DIV_ROUND_CLOSEST(host->sysclk, 2); 612 mmc->f_min = DIV_ROUND_CLOSEST(host->sysclk, CLK_DIV_MASK * 2); 613 mmc->ocr_avail = 0xffff00; /* Support 2.0v - 3.6v power. */ 614 615 if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) { 616 if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER || 617 PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) { 618 ret = -EPROBE_DEFER; 619 goto out; 620 } 621 if (!IS_ERR(host->dma_chan_tx)) { 622 dma_release_channel(host->dma_chan_tx); 623 host->dma_chan_tx = NULL; 624 } 625 if (!IS_ERR(host->dma_chan_rx)) { 626 dma_release_channel(host->dma_chan_rx); 627 host->dma_chan_rx = NULL; 628 } 629 dev_dbg(dev, "PIO mode transfer enabled\n"); 630 host->have_dma = false; 631 } else { 632 dev_dbg(dev, "DMA channels found (%p,%p)\n", 633 host->dma_chan_tx, host->dma_chan_rx); 634 host->have_dma = true; 635 636 memset(&cfg, 0, sizeof(cfg)); 637 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 638 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; 639 640 cfg.direction = DMA_MEM_TO_DEV; 641 cfg.src_addr = 0; 642 cfg.dst_addr = host->reg_phys + REG_DATA_WINDOW; 643 dmaengine_slave_config(host->dma_chan_tx, &cfg); 644 645 cfg.direction = DMA_DEV_TO_MEM; 646 cfg.src_addr = host->reg_phys + REG_DATA_WINDOW; 647 cfg.dst_addr = 0; 648 dmaengine_slave_config(host->dma_chan_rx, &cfg); 649 } 650 651 if (readl(host->base + REG_BUS_WIDTH) & BUS_WIDTH_4_SUPPORT) 652 mmc->caps |= MMC_CAP_4_BIT_DATA; 653 654 writel(0, host->base + REG_INTERRUPT_MASK); 655 656 writel(CMD_SDC_RESET, host->base + REG_COMMAND); 657 for (i = 0; i < MAX_RETRIES; i++) { 658 if (!(readl(host->base + REG_COMMAND) & CMD_SDC_RESET)) 659 break; 660 udelay(5); 661 } 662 663 ret = devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host); 664 if (ret) 665 goto out; 666 667 dev_set_drvdata(dev, mmc); 668 ret = mmc_add_host(mmc); 669 if (ret) 670 goto out; 671 672 dev_dbg(dev, "IRQ=%d, FIFO is %d bytes\n", irq, host->fifo_width); 673 674 return 0; 675 676 out: 677 if (!IS_ERR_OR_NULL(host->dma_chan_tx)) 678 dma_release_channel(host->dma_chan_tx); 679 if (!IS_ERR_OR_NULL(host->dma_chan_rx)) 680 dma_release_channel(host->dma_chan_rx); 681 out_mmc: 682 if (mmc) 683 mmc_free_host(mmc); 684 return ret; 685 } 686 687 static int moxart_remove(struct platform_device *pdev) 688 { 689 struct mmc_host *mmc = dev_get_drvdata(&pdev->dev); 690 struct moxart_host *host = mmc_priv(mmc); 691 692 dev_set_drvdata(&pdev->dev, NULL); 693 694 if (!IS_ERR_OR_NULL(host->dma_chan_tx)) 695 dma_release_channel(host->dma_chan_tx); 696 if (!IS_ERR_OR_NULL(host->dma_chan_rx)) 697 dma_release_channel(host->dma_chan_rx); 698 mmc_remove_host(mmc); 699 700 writel(0, host->base + REG_INTERRUPT_MASK); 701 writel(0, host->base + REG_POWER_CONTROL); 702 writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF, 703 host->base + REG_CLOCK_CONTROL); 704 mmc_free_host(mmc); 705 706 return 0; 707 } 708 709 static const struct of_device_id moxart_mmc_match[] = { 710 { .compatible = "moxa,moxart-mmc" }, 711 { .compatible = "faraday,ftsdc010" }, 712 { } 713 }; 714 MODULE_DEVICE_TABLE(of, moxart_mmc_match); 715 716 static struct platform_driver moxart_mmc_driver = { 717 .probe = moxart_probe, 718 .remove = moxart_remove, 719 .driver = { 720 .name = "mmc-moxart", 721 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 722 .of_match_table = moxart_mmc_match, 723 }, 724 }; 725 module_platform_driver(moxart_mmc_driver); 726 727 MODULE_ALIAS("platform:mmc-moxart"); 728 MODULE_DESCRIPTION("MOXA ART MMC driver"); 729 MODULE_LICENSE("GPL v2"); 730 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>"); 731