drivers/mmc/host/moxart-mmc.c

   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         long dma_time;
 261         struct dma_async_tx_descriptor *desc = NULL;
 262         struct dma_chan *dma_chan;
 263
 264         if (host->data_len == data->bytes_xfered)
 265                 return;
 266
 267         if (data->flags & MMC_DATA_WRITE) {
 268                 dma_chan = host->dma_chan_tx;
 269                 dir_slave = DMA_MEM_TO_DEV;
 270         } else {
 271                 dma_chan = host->dma_chan_rx;
 272                 dir_slave = DMA_DEV_TO_MEM;
 273         }
 274
 275         len = dma_map_sg(dma_chan->device->dev, data->sg,
 276                          data->sg_len, mmc_get_dma_dir(data));
 277
 278         if (len > 0) {
 279                 desc = dmaengine_prep_slave_sg(dma_chan, data->sg,
 280                                                len, dir_slave,
 281                                                DMA_PREP_INTERRUPT |
 282                                                DMA_CTRL_ACK);
 283         } else {
 284                 dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n");
 285         }
 286
 287         if (desc) {
 288                 host->tx_desc = desc;
 289                 desc->callback = moxart_dma_complete;
 290                 desc->callback_param = host;
 291                 dmaengine_submit(desc);
 292                 dma_async_issue_pending(dma_chan);
 293         }
 294
 295         data->bytes_xfered += host->data_remain;
 296
 297         dma_time = wait_for_completion_interruptible_timeout(
 298                    &host->dma_complete, host->timeout);
 299
 300         dma_unmap_sg(dma_chan->device->dev,
 301                      data->sg, data->sg_len,
 302                      mmc_get_dma_dir(data));
 303 }
 304
 305
 306 static void moxart_transfer_pio(struct moxart_host *host)
 307 {
 308         struct mmc_data *data = host->mrq->cmd->data;
 309         u32 *sgp, len = 0, remain, status;
 310
 311         if (host->data_len == data->bytes_xfered)
 312                 return;
 313
 314         sgp = sg_virt(host->cur_sg);
 315         remain = host->data_remain;
 316
 317         if (data->flags & MMC_DATA_WRITE) {
 318                 while (remain > 0) {
 319                         if (moxart_wait_for_status(host, FIFO_URUN, &status)
 320                              == -ETIMEDOUT) {
 321                                 data->error = -ETIMEDOUT;
 322                                 complete(&host->pio_complete);
 323                                 return;
 324                         }
 325                         for (len = 0; len < remain && len < host->fifo_width;) {
 326                                 iowrite32(*sgp, host->base + REG_DATA_WINDOW);
 327                                 sgp++;
 328                                 len += 4;
 329                         }
 330                         remain -= len;
 331                 }
 332
 333         } else {
 334                 while (remain > 0) {
 335                         if (moxart_wait_for_status(host, FIFO_ORUN, &status)
 336                             == -ETIMEDOUT) {
 337                                 data->error = -ETIMEDOUT;
 338                                 complete(&host->pio_complete);
 339                                 return;
 340                         }
 341                         for (len = 0; len < remain && len < host->fifo_width;) {
 342                                 *sgp = ioread32(host->base + REG_DATA_WINDOW);
 343                                 sgp++;
 344                                 len += 4;
 345                         }
 346                         remain -= len;
 347                 }
 348         }
 349
 350         data->bytes_xfered += host->data_remain - remain;
 351         host->data_remain = remain;
 352
 353         if (host->data_len != data->bytes_xfered)
 354                 moxart_next_sg(host);
 355         else
 356                 complete(&host->pio_complete);
 357 }
 358
 359 static void moxart_prepare_data(struct moxart_host *host)
 360 {
 361         struct mmc_data *data = host->mrq->cmd->data;
 362         u32 datactrl;
 363         int blksz_bits;
 364
 365         if (!data)
 366                 return;
 367
 368         host->data_len = data->blocks * data->blksz;
 369         blksz_bits = ffs(data->blksz) - 1;
 370         BUG_ON(1 << blksz_bits != data->blksz);
 371
 372         moxart_init_sg(host, data);
 373
 374         datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE);
 375
 376         if (data->flags & MMC_DATA_WRITE)
 377                 datactrl |= DCR_DATA_WRITE;
 378
 379         if ((host->data_len > host->fifo_width) && host->have_dma)
 380                 datactrl |= DCR_DMA_EN;
 381
 382         writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL);
 383         writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR);
 384         writel(host->rate, host->base + REG_DATA_TIMER);
 385         writel(host->data_len, host->base + REG_DATA_LENGTH);
 386         writel(datactrl, host->base + REG_DATA_CONTROL);
 387 }
 388
 389 static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
 390 {
 391         struct moxart_host *host = mmc_priv(mmc);
 392         long pio_time;
 393         unsigned long flags;
 394         u32 status;
 395
 396         spin_lock_irqsave(&host->lock, flags);
 397
 398         init_completion(&host->dma_complete);
 399         init_completion(&host->pio_complete);
 400
 401         host->mrq = mrq;
 402
 403         if (readl(host->base + REG_STATUS) & CARD_DETECT) {
 404                 mrq->cmd->error = -ETIMEDOUT;
 405                 goto request_done;
 406         }
 407
 408         moxart_prepare_data(host);
 409         moxart_send_command(host, host->mrq->cmd);
 410
 411         if (mrq->cmd->data) {
 412                 if ((host->data_len > host->fifo_width) && host->have_dma) {
 413
 414                         writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
 415
 416                         spin_unlock_irqrestore(&host->lock, flags);
 417
 418                         moxart_transfer_dma(mrq->cmd->data, host);
 419
 420                         spin_lock_irqsave(&host->lock, flags);
 421                 } else {
 422
 423                         writel(MASK_INTR_PIO, host->base + REG_INTERRUPT_MASK);
 424
 425                         spin_unlock_irqrestore(&host->lock, flags);
 426
 427                         /* PIO transfers start from interrupt. */
 428                         pio_time = wait_for_completion_interruptible_timeout(
 429                                    &host->pio_complete, host->timeout);
 430
 431                         spin_lock_irqsave(&host->lock, flags);
 432                 }
 433
 434                 if (host->is_removed) {
 435                         dev_err(mmc_dev(host->mmc), "card removed\n");
 436                         mrq->cmd->error = -ETIMEDOUT;
 437                         goto request_done;
 438                 }
 439
 440                 if (moxart_wait_for_status(host, MASK_DATA, &status)
 441                     == -ETIMEDOUT) {
 442                         mrq->cmd->data->error = -ETIMEDOUT;
 443                         goto request_done;
 444                 }
 445
 446                 if (status & DATA_CRC_FAIL)
 447                         mrq->cmd->data->error = -ETIMEDOUT;
 448
 449                 if (mrq->cmd->data->stop)
 450                         moxart_send_command(host, mrq->cmd->data->stop);
 451         }
 452
 453 request_done:
 454         spin_unlock_irqrestore(&host->lock, flags);
 455         mmc_request_done(host->mmc, mrq);
 456 }
 457
 458 static irqreturn_t moxart_irq(int irq, void *devid)
 459 {
 460         struct moxart_host *host = (struct moxart_host *)devid;
 461         u32 status;
 462         unsigned long flags;
 463
 464         spin_lock_irqsave(&host->lock, flags);
 465
 466         status = readl(host->base + REG_STATUS);
 467         if (status & CARD_CHANGE) {
 468                 host->is_removed = status & CARD_DETECT;
 469                 if (host->is_removed && host->have_dma) {
 470                         dmaengine_terminate_all(host->dma_chan_tx);
 471                         dmaengine_terminate_all(host->dma_chan_rx);
 472                 }
 473                 host->mrq = NULL;
 474                 writel(MASK_INTR_PIO, host->base + REG_CLEAR);
 475                 writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
 476                 mmc_detect_change(host->mmc, 0);
 477         }
 478         if (status & (FIFO_ORUN | FIFO_URUN) && host->mrq)
 479                 moxart_transfer_pio(host);
 480
 481         spin_unlock_irqrestore(&host->lock, flags);
 482
 483         return IRQ_HANDLED;
 484 }
 485
 486 static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 487 {
 488         struct moxart_host *host = mmc_priv(mmc);
 489         unsigned long flags;
 490         u8 power, div;
 491         u32 ctrl;
 492
 493         spin_lock_irqsave(&host->lock, flags);
 494
 495         if (ios->clock) {
 496                 for (div = 0; div < CLK_DIV_MASK; ++div) {
 497                         if (ios->clock >= host->sysclk / (2 * (div + 1)))
 498                                 break;
 499                 }
 500                 ctrl = CLK_SD | div;
 501                 host->rate = host->sysclk / (2 * (div + 1));
 502                 if (host->rate > host->sysclk)
 503                         ctrl |= CLK_HISPD;
 504                 writel(ctrl, host->base + REG_CLOCK_CONTROL);
 505         }
 506
 507         if (ios->power_mode == MMC_POWER_OFF) {
 508                 writel(readl(host->base + REG_POWER_CONTROL) & ~SD_POWER_ON,
 509                        host->base + REG_POWER_CONTROL);
 510         } else {
 511                 if (ios->vdd < MIN_POWER)
 512                         power = 0;
 513                 else
 514                         power = ios->vdd - MIN_POWER;
 515
 516                 writel(SD_POWER_ON | (u32) power,
 517                        host->base + REG_POWER_CONTROL);
 518         }
 519
 520         switch (ios->bus_width) {
 521         case MMC_BUS_WIDTH_4:
 522                 writel(BUS_WIDTH_4, host->base + REG_BUS_WIDTH);
 523                 break;
 524         default:
 525                 writel(BUS_WIDTH_1, host->base + REG_BUS_WIDTH);
 526                 break;
 527         }
 528
 529         spin_unlock_irqrestore(&host->lock, flags);
 530 }
 531
 532
 533 static int moxart_get_ro(struct mmc_host *mmc)
 534 {
 535         struct moxart_host *host = mmc_priv(mmc);
 536
 537         return !!(readl(host->base + REG_STATUS) & WRITE_PROT);
 538 }
 539
 540 static const struct mmc_host_ops moxart_ops = {
 541         .request = moxart_request,
 542         .set_ios = moxart_set_ios,
 543         .get_ro = moxart_get_ro,
 544 };
 545
 546 static int moxart_probe(struct platform_device *pdev)
 547 {
 548         struct device *dev = &pdev->dev;
 549         struct device_node *node = dev->of_node;
 550         struct resource res_mmc;
 551         struct mmc_host *mmc;
 552         struct moxart_host *host = NULL;
 553         struct dma_slave_config cfg;
 554         struct clk *clk;
 555         void __iomem *reg_mmc;
 556         int irq, ret;
 557         u32 i;
 558
 559         mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
 560         if (!mmc) {
 561                 dev_err(dev, "mmc_alloc_host failed\n");
 562                 ret = -ENOMEM;
 563                 goto out;
 564         }
 565
 566         ret = of_address_to_resource(node, 0, &res_mmc);
 567         if (ret) {
 568                 dev_err(dev, "of_address_to_resource failed\n");
 569                 goto out;
 570         }
 571
 572         irq = irq_of_parse_and_map(node, 0);
 573         if (irq <= 0) {
 574                 dev_err(dev, "irq_of_parse_and_map failed\n");
 575                 ret = -EINVAL;
 576                 goto out;
 577         }
 578
 579         clk = devm_clk_get(dev, NULL);
 580         if (IS_ERR(clk)) {
 581                 ret = PTR_ERR(clk);
 582                 goto out;
 583         }
 584
 585         reg_mmc = devm_ioremap_resource(dev, &res_mmc);
 586         if (IS_ERR(reg_mmc)) {
 587                 ret = PTR_ERR(reg_mmc);
 588                 goto out;
 589         }
 590
 591         ret = mmc_of_parse(mmc);
 592         if (ret)
 593                 goto out;
 594
 595         host = mmc_priv(mmc);
 596         host->mmc = mmc;
 597         host->base = reg_mmc;
 598         host->reg_phys = res_mmc.start;
 599         host->timeout = msecs_to_jiffies(1000);
 600         host->sysclk = clk_get_rate(clk);
 601         host->fifo_width = readl(host->base + REG_FEATURE) << 2;
 602         host->dma_chan_tx = dma_request_slave_channel_reason(dev, "tx");
 603         host->dma_chan_rx = dma_request_slave_channel_reason(dev, "rx");
 604
 605         spin_lock_init(&host->lock);
 606
 607         mmc->ops = &moxart_ops;
 608         mmc->f_max = DIV_ROUND_CLOSEST(host->sysclk, 2);
 609         mmc->f_min = DIV_ROUND_CLOSEST(host->sysclk, CLK_DIV_MASK * 2);
 610         mmc->ocr_avail = 0xffff00;      /* Support 2.0v - 3.6v power. */
 611
 612         if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) {
 613                 if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER ||
 614                     PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) {
 615                         ret = -EPROBE_DEFER;
 616                         goto out;
 617                 }
 618                 dev_dbg(dev, "PIO mode transfer enabled\n");
 619                 host->have_dma = false;
 620         } else {
 621                 dev_dbg(dev, "DMA channels found (%p,%p)\n",
 622                          host->dma_chan_tx, host->dma_chan_rx);
 623                 host->have_dma = true;
 624
 625                 memset(&cfg, 0, sizeof(cfg));
 626                 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 627                 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 628
 629                 cfg.direction = DMA_MEM_TO_DEV;
 630                 cfg.src_addr = 0;
 631                 cfg.dst_addr = host->reg_phys + REG_DATA_WINDOW;
 632                 dmaengine_slave_config(host->dma_chan_tx, &cfg);
 633
 634                 cfg.direction = DMA_DEV_TO_MEM;
 635                 cfg.src_addr = host->reg_phys + REG_DATA_WINDOW;
 636                 cfg.dst_addr = 0;
 637                 dmaengine_slave_config(host->dma_chan_rx, &cfg);
 638         }
 639
 640         if (readl(host->base + REG_BUS_WIDTH) & BUS_WIDTH_4_SUPPORT)
 641                 mmc->caps |= MMC_CAP_4_BIT_DATA;
 642
 643         writel(0, host->base + REG_INTERRUPT_MASK);
 644
 645         writel(CMD_SDC_RESET, host->base + REG_COMMAND);
 646         for (i = 0; i < MAX_RETRIES; i++) {
 647                 if (!(readl(host->base + REG_COMMAND) & CMD_SDC_RESET))
 648                         break;
 649                 udelay(5);
 650         }
 651
 652         ret = devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
 653         if (ret)
 654                 goto out;
 655
 656         dev_set_drvdata(dev, mmc);
 657         ret = mmc_add_host(mmc);
 658         if (ret)
 659                 goto out;
 660
 661         dev_dbg(dev, "IRQ=%d, FIFO is %d bytes\n", irq, host->fifo_width);
 662
 663         return 0;
 664
 665 out:
 666         if (mmc)
 667                 mmc_free_host(mmc);
 668         return ret;
 669 }
 670
 671 static int moxart_remove(struct platform_device *pdev)
 672 {
 673         struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
 674         struct moxart_host *host = mmc_priv(mmc);
 675
 676         dev_set_drvdata(&pdev->dev, NULL);
 677
 678         if (mmc) {
 679                 if (!IS_ERR(host->dma_chan_tx))
 680                         dma_release_channel(host->dma_chan_tx);
 681                 if (!IS_ERR(host->dma_chan_rx))
 682                         dma_release_channel(host->dma_chan_rx);
 683                 mmc_remove_host(mmc);
 684
 685                 writel(0, host->base + REG_INTERRUPT_MASK);
 686                 writel(0, host->base + REG_POWER_CONTROL);
 687                 writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
 688                        host->base + REG_CLOCK_CONTROL);
 689                 mmc_free_host(mmc);
 690         }
 691         return 0;
 692 }
 693
 694 static const struct of_device_id moxart_mmc_match[] = {
 695         { .compatible = "moxa,moxart-mmc" },
 696         { .compatible = "faraday,ftsdc010" },
 697         { }
 698 };
 699 MODULE_DEVICE_TABLE(of, moxart_mmc_match);
 700
 701 static struct platform_driver moxart_mmc_driver = {
 702         .probe      = moxart_probe,
 703         .remove     = moxart_remove,
 704         .driver     = {
 705                 .name           = "mmc-moxart",
 706                 .of_match_table = moxart_mmc_match,
 707         },
 708 };
 709 module_platform_driver(moxart_mmc_driver);
 710
 711 MODULE_ALIAS("platform:mmc-moxart");
 712 MODULE_DESCRIPTION("MOXA ART MMC driver");
 713 MODULE_LICENSE("GPL v2");
 714 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");