drivers/mmc/host/tmio_mmc.c

   1 /*
   2  *  linux/drivers/mmc/tmio_mmc.c
   3  *
   4  *  Copyright (C) 2004 Ian Molton
   5  *  Copyright (C) 2007 Ian Molton
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * Driver for the MMC / SD / SDIO cell found in:
  12  *
  13  * TC6393XB TC6391XB TC6387XB T7L66XB ASIC3
  14  *
  15  * This driver draws mainly on scattered spec sheets, Reverse engineering
  16  * of the toshiba e800  SD driver and some parts of the 2.4 ASIC3 driver (4 bit
  17  * support). (Further 4 bit support from a later datasheet).
  18  *
  19  * TODO:
  20  *   Investigate using a workqueue for PIO transfers
  21  *   Eliminate FIXMEs
  22  *   SDIO support
  23  *   Better Power management
  24  *   Handle MMC errors better
  25  *   double buffer support
  26  *
  27  */
  28 #include <linux/module.h>
  29 #include <linux/irq.h>
  30 #include <linux/device.h>
  31 #include <linux/delay.h>
  32 #include <linux/mmc/host.h>
  33 #include <linux/mfd/core.h>
  34 #include <linux/mfd/tmio.h>
  35
  36 #include "tmio_mmc.h"
  37
  38 static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
  39 {
  40         u32 clk = 0, clock;
  41
  42         if (new_clock) {
  43                 for (clock = host->mmc->f_min, clk = 0x80000080;
  44                         new_clock >= (clock<<1); clk >>= 1)
  45                         clock <<= 1;
  46
  47         /* Round the clock to the closest available. This is required
  48          * for some fussy cards that dont like to initialise below 400kHz
  49          */
  50                 if (new_clock - clock >= (clock << 1) - new_clock) {
  51                         clk >>= 1; clock <<= 1;
  52                 }
  53
  54         /* Clock enable */
  55                 clk |= 0x100;
  56         }
  57
  58         if (host->set_no_clk_div)
  59                 host->set_no_clk_div(host->pdev, (clk>>22) & 1);
  60
  61         sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & 0x1ff);
  62 }
  63
  64 static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
  65 {
  66         sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
  67         msleep(10);
  68         sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~0x0100 &
  69                 sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
  70         msleep(10);
  71 }
  72
  73 static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
  74 {
  75         sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, 0x0100 |
  76                 sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
  77         msleep(10);
  78         sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
  79         msleep(10);
  80 }
  81
  82 static void reset(struct tmio_mmc_host *host)
  83 {
  84         /* FIXME - should we set stop clock reg here */
  85         sd_ctrl_write16(host, CTL_RESET_SD, 0x0000);
  86         sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
  87         msleep(10);
  88         sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
  89         sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
  90         msleep(10);
  91 }
  92
  93 static void
  94 tmio_mmc_finish_request(struct tmio_mmc_host *host)
  95 {
  96         struct mmc_request *mrq = host->mrq;
  97
  98         host->mrq = NULL;
  99         host->cmd = NULL;
 100         host->data = NULL;
 101
 102         mmc_request_done(host->mmc, mrq);
 103 }
 104
 105 /* These are the bitmasks the tmio chip requires to implement the MMC response
 106  * types. Note that R1 and R6 are the same in this scheme. */
 107 #define APP_CMD        0x0040
 108 #define RESP_NONE      0x0300
 109 #define RESP_R1        0x0400
 110 #define RESP_R1B       0x0500
 111 #define RESP_R2        0x0600
 112 #define RESP_R3        0x0700
 113 #define DATA_PRESENT   0x0800
 114 #define TRANSFER_READ  0x1000
 115 #define TRANSFER_MULTI 0x2000
 116 #define SECURITY_CMD   0x4000
 117
 118 static int
 119 tmio_mmc_start_command(struct tmio_mmc_host *host, struct mmc_command *cmd)
 120 {
 121         struct mmc_data *data = host->data;
 122         int c = cmd->opcode;
 123
 124         /* Command 12 is handled by hardware */
 125         if (cmd->opcode == 12 && !cmd->arg) {
 126                 sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x001);
 127                 return 0;
 128         }
 129
 130         switch (mmc_resp_type(cmd)) {
 131         case MMC_RSP_NONE: c |= RESP_NONE; break;
 132         case MMC_RSP_R1:   c |= RESP_R1;   break;
 133         case MMC_RSP_R1B:  c |= RESP_R1B;  break;
 134         case MMC_RSP_R2:   c |= RESP_R2;   break;
 135         case MMC_RSP_R3:   c |= RESP_R3;   break;
 136         default:
 137                 pr_debug("Unknown response type %d\n", mmc_resp_type(cmd));
 138                 return -EINVAL;
 139         }
 140
 141         host->cmd = cmd;
 142
 143 /* FIXME - this seems to be ok comented out but the spec suggest this bit should
 144  *         be set when issuing app commands.
 145  *      if(cmd->flags & MMC_FLAG_ACMD)
 146  *              c |= APP_CMD;
 147  */
 148         if (data) {
 149                 c |= DATA_PRESENT;
 150                 if (data->blocks > 1) {
 151                         sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x100);
 152                         c |= TRANSFER_MULTI;
 153                 }
 154                 if (data->flags & MMC_DATA_READ)
 155                         c |= TRANSFER_READ;
 156         }
 157
 158         enable_mmc_irqs(host, TMIO_MASK_CMD);
 159
 160         /* Fire off the command */
 161         sd_ctrl_write32(host, CTL_ARG_REG, cmd->arg);
 162         sd_ctrl_write16(host, CTL_SD_CMD, c);
 163
 164         return 0;
 165 }
 166
 167 /* This chip always returns (at least?) as much data as you ask for.
 168  * I'm unsure what happens if you ask for less than a block. This should be
 169  * looked into to ensure that a funny length read doesnt hose the controller.
 170  *
 171  */
 172 static inline void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 173 {
 174         struct mmc_data *data = host->data;
 175         unsigned short *buf;
 176         unsigned int count;
 177         unsigned long flags;
 178
 179         if (!data) {
 180                 pr_debug("Spurious PIO IRQ\n");
 181                 return;
 182         }
 183
 184         buf = (unsigned short *)(tmio_mmc_kmap_atomic(host, &flags) +
 185               host->sg_off);
 186
 187         count = host->sg_ptr->length - host->sg_off;
 188         if (count > data->blksz)
 189                 count = data->blksz;
 190
 191         pr_debug("count: %08x offset: %08x flags %08x\n",
 192             count, host->sg_off, data->flags);
 193
 194         /* Transfer the data */
 195         if (data->flags & MMC_DATA_READ)
 196                 sd_ctrl_read16_rep(host, CTL_SD_DATA_PORT, buf, count >> 1);
 197         else
 198                 sd_ctrl_write16_rep(host, CTL_SD_DATA_PORT, buf, count >> 1);
 199
 200         host->sg_off += count;
 201
 202         tmio_mmc_kunmap_atomic(host, &flags);
 203
 204         if (host->sg_off == host->sg_ptr->length)
 205                 tmio_mmc_next_sg(host);
 206
 207         return;
 208 }
 209
 210 static inline void tmio_mmc_data_irq(struct tmio_mmc_host *host)
 211 {
 212         struct mmc_data *data = host->data;
 213         struct mmc_command *stop;
 214
 215         host->data = NULL;
 216
 217         if (!data) {
 218                 pr_debug("Spurious data end IRQ\n");
 219                 return;
 220         }
 221         stop = data->stop;
 222
 223         /* FIXME - return correct transfer count on errors */
 224         if (!data->error)
 225                 data->bytes_xfered = data->blocks * data->blksz;
 226         else
 227                 data->bytes_xfered = 0;
 228
 229         pr_debug("Completed data request\n");
 230
 231         /*FIXME - other drivers allow an optional stop command of any given type
 232          *        which we dont do, as the chip can auto generate them.
 233          *        Perhaps we can be smarter about when to use auto CMD12 and
 234          *        only issue the auto request when we know this is the desired
 235          *        stop command, allowing fallback to the stop command the
 236          *        upper layers expect. For now, we do what works.
 237          */
 238
 239         if (data->flags & MMC_DATA_READ)
 240                 disable_mmc_irqs(host, TMIO_MASK_READOP);
 241         else
 242                 disable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 243
 244         if (stop) {
 245                 if (stop->opcode == 12 && !stop->arg)
 246                         sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x000);
 247                 else
 248                         BUG();
 249         }
 250
 251         tmio_mmc_finish_request(host);
 252 }
 253
 254 static inline void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
 255         unsigned int stat)
 256 {
 257         struct mmc_command *cmd = host->cmd;
 258         int i, addr;
 259
 260         if (!host->cmd) {
 261                 pr_debug("Spurious CMD irq\n");
 262                 return;
 263         }
 264
 265         host->cmd = NULL;
 266
 267         /* This controller is sicker than the PXA one. Not only do we need to
 268          * drop the top 8 bits of the first response word, we also need to
 269          * modify the order of the response for short response command types.
 270          */
 271
 272         for (i = 3, addr = CTL_RESPONSE ; i >= 0 ; i--, addr += 4)
 273                 cmd->resp[i] = sd_ctrl_read32(host, addr);
 274
 275         if (cmd->flags &  MMC_RSP_136) {
 276                 cmd->resp[0] = (cmd->resp[0] << 8) | (cmd->resp[1] >> 24);
 277                 cmd->resp[1] = (cmd->resp[1] << 8) | (cmd->resp[2] >> 24);
 278                 cmd->resp[2] = (cmd->resp[2] << 8) | (cmd->resp[3] >> 24);
 279                 cmd->resp[3] <<= 8;
 280         } else if (cmd->flags & MMC_RSP_R3) {
 281                 cmd->resp[0] = cmd->resp[3];
 282         }
 283
 284         if (stat & TMIO_STAT_CMDTIMEOUT)
 285                 cmd->error = -ETIMEDOUT;
 286         else if (stat & TMIO_STAT_CRCFAIL && cmd->flags & MMC_RSP_CRC)
 287                 cmd->error = -EILSEQ;
 288
 289         /* If there is data to handle we enable data IRQs here, and
 290          * we will ultimatley finish the request in the data_end handler.
 291          * If theres no data or we encountered an error, finish now.
 292          */
 293         if (host->data && !cmd->error) {
 294                 if (host->data->flags & MMC_DATA_READ)
 295                         enable_mmc_irqs(host, TMIO_MASK_READOP);
 296                 else
 297                         enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 298         } else {
 299                 tmio_mmc_finish_request(host);
 300         }
 301
 302         return;
 303 }
 304
 305
 306 static irqreturn_t tmio_mmc_irq(int irq, void *devid)
 307 {
 308         struct tmio_mmc_host *host = devid;
 309         unsigned int ireg, irq_mask, status;
 310
 311         pr_debug("MMC IRQ begin\n");
 312
 313         status = sd_ctrl_read32(host, CTL_STATUS);
 314         irq_mask = sd_ctrl_read32(host, CTL_IRQ_MASK);
 315         ireg = status & TMIO_MASK_IRQ & ~irq_mask;
 316
 317         pr_debug_status(status);
 318         pr_debug_status(ireg);
 319
 320         if (!ireg) {
 321                 disable_mmc_irqs(host, status & ~irq_mask);
 322
 323                 pr_debug("tmio_mmc: Spurious irq, disabling! "
 324                         "0x%08x 0x%08x 0x%08x\n", status, irq_mask, ireg);
 325                 pr_debug_status(status);
 326
 327                 goto out;
 328         }
 329
 330         while (ireg) {
 331                 /* Card insert / remove attempts */
 332                 if (ireg & (TMIO_STAT_CARD_INSERT | TMIO_STAT_CARD_REMOVE)) {
 333                         ack_mmc_irqs(host, TMIO_STAT_CARD_INSERT |
 334                                 TMIO_STAT_CARD_REMOVE);
 335                         mmc_detect_change(host->mmc, 0);
 336                 }
 337
 338                 /* CRC and other errors */
 339 /*              if (ireg & TMIO_STAT_ERR_IRQ)
 340  *                      handled |= tmio_error_irq(host, irq, stat);
 341  */
 342
 343                 /* Command completion */
 344                 if (ireg & TMIO_MASK_CMD) {
 345                         ack_mmc_irqs(host, TMIO_MASK_CMD);
 346                         tmio_mmc_cmd_irq(host, status);
 347                 }
 348
 349                 /* Data transfer */
 350                 if (ireg & (TMIO_STAT_RXRDY | TMIO_STAT_TXRQ)) {
 351                         ack_mmc_irqs(host, TMIO_STAT_RXRDY | TMIO_STAT_TXRQ);
 352                         tmio_mmc_pio_irq(host);
 353                 }
 354
 355                 /* Data transfer completion */
 356                 if (ireg & TMIO_STAT_DATAEND) {
 357                         ack_mmc_irqs(host, TMIO_STAT_DATAEND);
 358                         tmio_mmc_data_irq(host);
 359                 }
 360
 361                 /* Check status - keep going until we've handled it all */
 362                 status = sd_ctrl_read32(host, CTL_STATUS);
 363                 irq_mask = sd_ctrl_read32(host, CTL_IRQ_MASK);
 364                 ireg = status & TMIO_MASK_IRQ & ~irq_mask;
 365
 366                 pr_debug("Status at end of loop: %08x\n", status);
 367                 pr_debug_status(status);
 368         }
 369         pr_debug("MMC IRQ end\n");
 370
 371 out:
 372         return IRQ_HANDLED;
 373 }
 374
 375 static int tmio_mmc_start_data(struct tmio_mmc_host *host,
 376         struct mmc_data *data)
 377 {
 378         pr_debug("setup data transfer: blocksize %08x  nr_blocks %d\n",
 379             data->blksz, data->blocks);
 380
 381         /* Hardware cannot perform 1 and 2 byte requests in 4 bit mode */
 382         if (data->blksz < 4 && host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) {
 383                 printk(KERN_ERR "%s: %d byte block unsupported in 4 bit mode\n",
 384                         mmc_hostname(host->mmc), data->blksz);
 385                 return -EINVAL;
 386         }
 387
 388         tmio_mmc_init_sg(host, data);
 389         host->data = data;
 390
 391         /* Set transfer length / blocksize */
 392         sd_ctrl_write16(host, CTL_SD_XFER_LEN, data->blksz);
 393         sd_ctrl_write16(host, CTL_XFER_BLK_COUNT, data->blocks);
 394
 395         return 0;
 396 }
 397
 398 /* Process requests from the MMC layer */
 399 static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 400 {
 401         struct tmio_mmc_host *host = mmc_priv(mmc);
 402         int ret;
 403
 404         if (host->mrq)
 405                 pr_debug("request not null\n");
 406
 407         host->mrq = mrq;
 408
 409         if (mrq->data) {
 410                 ret = tmio_mmc_start_data(host, mrq->data);
 411                 if (ret)
 412                         goto fail;
 413         }
 414
 415         ret = tmio_mmc_start_command(host, mrq->cmd);
 416
 417         if (!ret)
 418                 return;
 419
 420 fail:
 421         mrq->cmd->error = ret;
 422         mmc_request_done(mmc, mrq);
 423 }
 424
 425 /* Set MMC clock / power.
 426  * Note: This controller uses a simple divider scheme therefore it cannot
 427  * run a MMC card at full speed (20MHz). The max clock is 24MHz on SD, but as
 428  * MMC wont run that fast, it has to be clocked at 12MHz which is the next
 429  * slowest setting.
 430  */
 431 static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 432 {
 433         struct tmio_mmc_host *host = mmc_priv(mmc);
 434
 435         if (ios->clock)
 436                 tmio_mmc_set_clock(host, ios->clock);
 437
 438         /* Power sequence - OFF -> UP -> ON */
 439         switch (ios->power_mode) {
 440         case MMC_POWER_OFF: /* power down SD bus */
 441                 if (host->set_pwr)
 442                         host->set_pwr(host->pdev, 0);
 443                 tmio_mmc_clk_stop(host);
 444                 break;
 445         case MMC_POWER_UP: /* power up SD bus */
 446                 if (host->set_pwr)
 447                         host->set_pwr(host->pdev, 1);
 448                 break;
 449         case MMC_POWER_ON: /* enable bus clock */
 450                 tmio_mmc_clk_start(host);
 451                 break;
 452         }
 453
 454         switch (ios->bus_width) {
 455         case MMC_BUS_WIDTH_1:
 456                 sd_ctrl_write16(host, CTL_SD_MEM_CARD_OPT, 0x80e0);
 457         break;
 458         case MMC_BUS_WIDTH_4:
 459                 sd_ctrl_write16(host, CTL_SD_MEM_CARD_OPT, 0x00e0);
 460         break;
 461         }
 462
 463         /* Let things settle. delay taken from winCE driver */
 464         udelay(140);
 465 }
 466
 467 static int tmio_mmc_get_ro(struct mmc_host *mmc)
 468 {
 469         struct tmio_mmc_host *host = mmc_priv(mmc);
 470
 471         return (sd_ctrl_read16(host, CTL_STATUS) & TMIO_STAT_WRPROTECT) ? 0 : 1;
 472 }
 473
 474 static struct mmc_host_ops tmio_mmc_ops = {
 475         .request        = tmio_mmc_request,
 476         .set_ios        = tmio_mmc_set_ios,
 477         .get_ro         = tmio_mmc_get_ro,
 478 };
 479
 480 #ifdef CONFIG_PM
 481 static int tmio_mmc_suspend(struct platform_device *dev, pm_message_t state)
 482 {
 483         struct mfd_cell *cell = (struct mfd_cell *)dev->dev.platform_data;
 484         struct mmc_host *mmc = platform_get_drvdata(dev);
 485         int ret;
 486
 487         ret = mmc_suspend_host(mmc, state);
 488
 489         /* Tell MFD core it can disable us now.*/
 490         if (!ret && cell->suspend)
 491                 cell->suspend(dev);
 492
 493         return ret;
 494 }
 495
 496 static int tmio_mmc_resume(struct platform_device *dev)
 497 {
 498         struct mfd_cell *cell = (struct mfd_cell *)dev->dev.platform_data;
 499         struct mmc_host *mmc = platform_get_drvdata(dev);
 500         int ret = 0;
 501
 502         /* Tell the MFD core we are ready to be enabled */
 503         if (cell->resume) {
 504                 ret = cell->resume(dev);
 505                 if (ret)
 506                         goto out;
 507         }
 508
 509         mmc_resume_host(mmc);
 510
 511 out:
 512         return ret;
 513 }
 514 #else
 515 #define tmio_mmc_suspend NULL
 516 #define tmio_mmc_resume NULL
 517 #endif
 518
 519 static int __devinit tmio_mmc_probe(struct platform_device *dev)
 520 {
 521         struct mfd_cell *cell = (struct mfd_cell *)dev->dev.platform_data;
 522         struct tmio_mmc_data *pdata;
 523         struct resource *res_ctl;
 524         struct tmio_mmc_host *host;
 525         struct mmc_host *mmc;
 526         int ret = -EINVAL;
 527
 528         if (dev->num_resources != 2)
 529                 goto out;
 530
 531         res_ctl = platform_get_resource(dev, IORESOURCE_MEM, 0);
 532         if (!res_ctl)
 533                 goto out;
 534
 535         pdata = cell->driver_data;
 536         if (!pdata || !pdata->hclk)
 537                 goto out;
 538
 539         ret = -ENOMEM;
 540
 541         mmc = mmc_alloc_host(sizeof(struct tmio_mmc_host), &dev->dev);
 542         if (!mmc)
 543                 goto out;
 544
 545         host = mmc_priv(mmc);
 546         host->mmc = mmc;
 547         host->pdev = dev;
 548         platform_set_drvdata(dev, mmc);
 549
 550         host->set_pwr = pdata->set_pwr;
 551         host->set_no_clk_div = pdata->set_no_clk_div;
 552
 553         /* SD control register space size is 0x200, 0x400 for bus_shift=1 */
 554         host->bus_shift = resource_size(res_ctl) >> 10;
 555
 556         host->ctl = ioremap(res_ctl->start, resource_size(res_ctl));
 557         if (!host->ctl)
 558                 goto host_free;
 559
 560         mmc->ops = &tmio_mmc_ops;
 561         mmc->caps = MMC_CAP_4_BIT_DATA;
 562         mmc->f_max = pdata->hclk;
 563         mmc->f_min = mmc->f_max / 512;
 564         mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
 565
 566         /* Tell the MFD core we are ready to be enabled */
 567         if (cell->enable) {
 568                 ret = cell->enable(dev);
 569                 if (ret)
 570                         goto unmap_ctl;
 571         }
 572
 573         tmio_mmc_clk_stop(host);
 574         reset(host);
 575
 576         ret = platform_get_irq(dev, 0);
 577         if (ret >= 0)
 578                 host->irq = ret;
 579         else
 580                 goto unmap_ctl;
 581
 582         disable_mmc_irqs(host, TMIO_MASK_ALL);
 583
 584         ret = request_irq(host->irq, tmio_mmc_irq, IRQF_DISABLED |
 585                 IRQF_TRIGGER_FALLING, "tmio-mmc", host);
 586         if (ret)
 587                 goto unmap_ctl;
 588
 589         mmc_add_host(mmc);
 590
 591         printk(KERN_INFO "%s at 0x%08lx irq %d\n", mmc_hostname(host->mmc),
 592                (unsigned long)host->ctl, host->irq);
 593
 594         /* Unmask the IRQs we want to know about */
 595         enable_mmc_irqs(host, TMIO_MASK_IRQ);
 596
 597         return 0;
 598
 599 unmap_ctl:
 600         iounmap(host->ctl);
 601 host_free:
 602         mmc_free_host(mmc);
 603 out:
 604         return ret;
 605 }
 606
 607 static int __devexit tmio_mmc_remove(struct platform_device *dev)
 608 {
 609         struct mmc_host *mmc = platform_get_drvdata(dev);
 610
 611         platform_set_drvdata(dev, NULL);
 612
 613         if (mmc) {
 614                 struct tmio_mmc_host *host = mmc_priv(mmc);
 615                 mmc_remove_host(mmc);
 616                 free_irq(host->irq, host);
 617                 iounmap(host->ctl);
 618                 mmc_free_host(mmc);
 619         }
 620
 621         return 0;
 622 }
 623
 624 /* ------------------- device registration ----------------------- */
 625
 626 static struct platform_driver tmio_mmc_driver = {
 627         .driver = {
 628                 .name = "tmio-mmc",
 629                 .owner = THIS_MODULE,
 630         },
 631         .probe = tmio_mmc_probe,
 632         .remove = __devexit_p(tmio_mmc_remove),
 633         .suspend = tmio_mmc_suspend,
 634         .resume = tmio_mmc_resume,
 635 };
 636
 637
 638 static int __init tmio_mmc_init(void)
 639 {
 640         return platform_driver_register(&tmio_mmc_driver);
 641 }
 642
 643 static void __exit tmio_mmc_exit(void)
 644 {
 645         platform_driver_unregister(&tmio_mmc_driver);
 646 }
 647
 648 module_init(tmio_mmc_init);
 649 module_exit(tmio_mmc_exit);
 650
 651 MODULE_DESCRIPTION("Toshiba TMIO SD/MMC driver");
 652 MODULE_AUTHOR("Ian Molton <spyro@f2s.com>");
 653 MODULE_LICENSE("GPL v2");
 654 MODULE_ALIAS("platform:tmio-mmc");