drivers/mmc/host/atmel-mci.c

   1 /*
   2  * Atmel MultiMedia Card Interface driver
   3  *
   4  * Copyright (C) 2004-2008 Atmel Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/blkdev.h>
  11 #include <linux/clk.h>
  12 #include <linux/debugfs.h>
  13 #include <linux/device.h>
  14 #include <linux/err.h>
  15 #include <linux/gpio.h>
  16 #include <linux/init.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/ioport.h>
  19 #include <linux/module.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/scatterlist.h>
  22 #include <linux/seq_file.h>
  23 #include <linux/stat.h>
  24
  25 #include <linux/mmc/host.h>
  26
  27 #include <asm/atmel-mci.h>
  28 #include <asm/io.h>
  29 #include <asm/unaligned.h>
  30
  31 #include <mach/board.h>
  32
  33 #include "atmel-mci-regs.h"
  34
  35 #define ATMCI_DATA_ERROR_FLAGS  (MCI_DCRCE | MCI_DTOE | MCI_OVRE | MCI_UNRE)
  36
  37 enum {
  38         EVENT_CMD_COMPLETE = 0,
  39         EVENT_DATA_ERROR,
  40         EVENT_DATA_COMPLETE,
  41         EVENT_STOP_SENT,
  42         EVENT_STOP_COMPLETE,
  43         EVENT_XFER_COMPLETE,
  44 };
  45
  46 struct atmel_mci {
  47         struct mmc_host         *mmc;
  48         void __iomem            *regs;
  49
  50         struct scatterlist      *sg;
  51         unsigned int            pio_offset;
  52
  53         struct mmc_request      *mrq;
  54         struct mmc_command      *cmd;
  55         struct mmc_data         *data;
  56
  57         u32                     cmd_status;
  58         u32                     data_status;
  59         u32                     stop_status;
  60         u32                     stop_cmdr;
  61
  62         u32                     mode_reg;
  63         u32                     sdc_reg;
  64
  65         struct tasklet_struct   tasklet;
  66         unsigned long           pending_events;
  67         unsigned long           completed_events;
  68
  69         int                     present;
  70         int                     detect_pin;
  71         int                     wp_pin;
  72
  73         /* For detect pin debouncing */
  74         struct timer_list       detect_timer;
  75
  76         unsigned long           bus_hz;
  77         unsigned long           mapbase;
  78         struct clk              *mck;
  79         struct platform_device  *pdev;
  80 };
  81
  82 #define atmci_is_completed(host, event)                         \
  83         test_bit(event, &host->completed_events)
  84 #define atmci_test_and_clear_pending(host, event)               \
  85         test_and_clear_bit(event, &host->pending_events)
  86 #define atmci_test_and_set_completed(host, event)               \
  87         test_and_set_bit(event, &host->completed_events)
  88 #define atmci_set_completed(host, event)                        \
  89         set_bit(event, &host->completed_events)
  90 #define atmci_set_pending(host, event)                          \
  91         set_bit(event, &host->pending_events)
  92 #define atmci_clear_pending(host, event)                        \
  93         clear_bit(event, &host->pending_events)
  94
  95 /*
  96  * The debugfs stuff below is mostly optimized away when
  97  * CONFIG_DEBUG_FS is not set.
  98  */
  99 static int atmci_req_show(struct seq_file *s, void *v)
 100 {
 101         struct atmel_mci        *host = s->private;
 102         struct mmc_request      *mrq = host->mrq;
 103         struct mmc_command      *cmd;
 104         struct mmc_command      *stop;
 105         struct mmc_data         *data;
 106
 107         /* Make sure we get a consistent snapshot */
 108         spin_lock_irq(&host->mmc->lock);
 109
 110         if (mrq) {
 111                 cmd = mrq->cmd;
 112                 data = mrq->data;
 113                 stop = mrq->stop;
 114
 115                 if (cmd)
 116                         seq_printf(s,
 117                                 "CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
 118                                 cmd->opcode, cmd->arg, cmd->flags,
 119                                 cmd->resp[0], cmd->resp[1], cmd->resp[2],
 120                                 cmd->resp[2], cmd->error);
 121                 if (data)
 122                         seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
 123                                 data->bytes_xfered, data->blocks,
 124                                 data->blksz, data->flags, data->error);
 125                 if (stop)
 126                         seq_printf(s,
 127                                 "CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
 128                                 stop->opcode, stop->arg, stop->flags,
 129                                 stop->resp[0], stop->resp[1], stop->resp[2],
 130                                 stop->resp[2], stop->error);
 131         }
 132
 133         spin_unlock_irq(&host->mmc->lock);
 134
 135         return 0;
 136 }
 137
 138 static int atmci_req_open(struct inode *inode, struct file *file)
 139 {
 140         return single_open(file, atmci_req_show, inode->i_private);
 141 }
 142
 143 static const struct file_operations atmci_req_fops = {
 144         .owner          = THIS_MODULE,
 145         .open           = atmci_req_open,
 146         .read           = seq_read,
 147         .llseek         = seq_lseek,
 148         .release        = single_release,
 149 };
 150
 151 static void atmci_show_status_reg(struct seq_file *s,
 152                 const char *regname, u32 value)
 153 {
 154         static const char       *sr_bit[] = {
 155                 [0]     = "CMDRDY",
 156                 [1]     = "RXRDY",
 157                 [2]     = "TXRDY",
 158                 [3]     = "BLKE",
 159                 [4]     = "DTIP",
 160                 [5]     = "NOTBUSY",
 161                 [8]     = "SDIOIRQA",
 162                 [9]     = "SDIOIRQB",
 163                 [16]    = "RINDE",
 164                 [17]    = "RDIRE",
 165                 [18]    = "RCRCE",
 166                 [19]    = "RENDE",
 167                 [20]    = "RTOE",
 168                 [21]    = "DCRCE",
 169                 [22]    = "DTOE",
 170                 [30]    = "OVRE",
 171                 [31]    = "UNRE",
 172         };
 173         unsigned int            i;
 174
 175         seq_printf(s, "%s:\t0x%08x", regname, value);
 176         for (i = 0; i < ARRAY_SIZE(sr_bit); i++) {
 177                 if (value & (1 << i)) {
 178                         if (sr_bit[i])
 179                                 seq_printf(s, " %s", sr_bit[i]);
 180                         else
 181                                 seq_puts(s, " UNKNOWN");
 182                 }
 183         }
 184         seq_putc(s, '\n');
 185 }
 186
 187 static int atmci_regs_show(struct seq_file *s, void *v)
 188 {
 189         struct atmel_mci        *host = s->private;
 190         u32                     *buf;
 191
 192         buf = kmalloc(MCI_REGS_SIZE, GFP_KERNEL);
 193         if (!buf)
 194                 return -ENOMEM;
 195
 196         /* Grab a more or less consistent snapshot */
 197         spin_lock_irq(&host->mmc->lock);
 198         clk_enable(host->mck);
 199         memcpy_fromio(buf, host->regs, MCI_REGS_SIZE);
 200         clk_disable(host->mck);
 201         spin_unlock_irq(&host->mmc->lock);
 202
 203         seq_printf(s, "MR:\t0x%08x%s%s CLKDIV=%u\n",
 204                         buf[MCI_MR / 4],
 205                         buf[MCI_MR / 4] & MCI_MR_RDPROOF ? " RDPROOF" : "",
 206                         buf[MCI_MR / 4] & MCI_MR_WRPROOF ? " WRPROOF" : "",
 207                         buf[MCI_MR / 4] & 0xff);
 208         seq_printf(s, "DTOR:\t0x%08x\n", buf[MCI_DTOR / 4]);
 209         seq_printf(s, "SDCR:\t0x%08x\n", buf[MCI_SDCR / 4]);
 210         seq_printf(s, "ARGR:\t0x%08x\n", buf[MCI_ARGR / 4]);
 211         seq_printf(s, "BLKR:\t0x%08x BCNT=%u BLKLEN=%u\n",
 212                         buf[MCI_BLKR / 4],
 213                         buf[MCI_BLKR / 4] & 0xffff,
 214                         (buf[MCI_BLKR / 4] >> 16) & 0xffff);
 215
 216         /* Don't read RSPR and RDR; it will consume the data there */
 217
 218         atmci_show_status_reg(s, "SR", buf[MCI_SR / 4]);
 219         atmci_show_status_reg(s, "IMR", buf[MCI_IMR / 4]);
 220
 221         kfree(buf);
 222
 223         return 0;
 224 }
 225
 226 static int atmci_regs_open(struct inode *inode, struct file *file)
 227 {
 228         return single_open(file, atmci_regs_show, inode->i_private);
 229 }
 230
 231 static const struct file_operations atmci_regs_fops = {
 232         .owner          = THIS_MODULE,
 233         .open           = atmci_regs_open,
 234         .read           = seq_read,
 235         .llseek         = seq_lseek,
 236         .release        = single_release,
 237 };
 238
 239 static void atmci_init_debugfs(struct atmel_mci *host)
 240 {
 241         struct mmc_host *mmc;
 242         struct dentry   *root;
 243         struct dentry   *node;
 244
 245         mmc = host->mmc;
 246         root = mmc->debugfs_root;
 247         if (!root)
 248                 return;
 249
 250         node = debugfs_create_file("regs", S_IRUSR, root, host,
 251                         &atmci_regs_fops);
 252         if (IS_ERR(node))
 253                 return;
 254         if (!node)
 255                 goto err;
 256
 257         node = debugfs_create_file("req", S_IRUSR, root, host, &atmci_req_fops);
 258         if (!node)
 259                 goto err;
 260
 261         node = debugfs_create_x32("pending_events", S_IRUSR, root,
 262                                      (u32 *)&host->pending_events);
 263         if (!node)
 264                 goto err;
 265
 266         node = debugfs_create_x32("completed_events", S_IRUSR, root,
 267                                      (u32 *)&host->completed_events);
 268         if (!node)
 269                 goto err;
 270
 271         return;
 272
 273 err:
 274         dev_err(&host->pdev->dev,
 275                 "failed to initialize debugfs for controller\n");
 276 }
 277
 278 static void atmci_enable(struct atmel_mci *host)
 279 {
 280         clk_enable(host->mck);
 281         mci_writel(host, CR, MCI_CR_MCIEN);
 282         mci_writel(host, MR, host->mode_reg);
 283         mci_writel(host, SDCR, host->sdc_reg);
 284 }
 285
 286 static void atmci_disable(struct atmel_mci *host)
 287 {
 288         mci_writel(host, CR, MCI_CR_SWRST);
 289
 290         /* Stall until write is complete, then disable the bus clock */
 291         mci_readl(host, SR);
 292         clk_disable(host->mck);
 293 }
 294
 295 static inline unsigned int ns_to_clocks(struct atmel_mci *host,
 296                                         unsigned int ns)
 297 {
 298         return (ns * (host->bus_hz / 1000000) + 999) / 1000;
 299 }
 300
 301 static void atmci_set_timeout(struct atmel_mci *host,
 302                               struct mmc_data *data)
 303 {
 304         static unsigned dtomul_to_shift[] = {
 305                 0, 4, 7, 8, 10, 12, 16, 20
 306         };
 307         unsigned        timeout;
 308         unsigned        dtocyc;
 309         unsigned        dtomul;
 310
 311         timeout = ns_to_clocks(host, data->timeout_ns) + data->timeout_clks;
 312
 313         for (dtomul = 0; dtomul < 8; dtomul++) {
 314                 unsigned shift = dtomul_to_shift[dtomul];
 315                 dtocyc = (timeout + (1 << shift) - 1) >> shift;
 316                 if (dtocyc < 15)
 317                         break;
 318         }
 319
 320         if (dtomul >= 8) {
 321                 dtomul = 7;
 322                 dtocyc = 15;
 323         }
 324
 325         dev_vdbg(&host->mmc->class_dev, "setting timeout to %u cycles\n",
 326                         dtocyc << dtomul_to_shift[dtomul]);
 327         mci_writel(host, DTOR, (MCI_DTOMUL(dtomul) | MCI_DTOCYC(dtocyc)));
 328 }
 329
 330 /*
 331  * Return mask with command flags to be enabled for this command.
 332  */
 333 static u32 atmci_prepare_command(struct mmc_host *mmc,
 334                                  struct mmc_command *cmd)
 335 {
 336         struct mmc_data *data;
 337         u32             cmdr;
 338
 339         cmd->error = -EINPROGRESS;
 340
 341         cmdr = MCI_CMDR_CMDNB(cmd->opcode);
 342
 343         if (cmd->flags & MMC_RSP_PRESENT) {
 344                 if (cmd->flags & MMC_RSP_136)
 345                         cmdr |= MCI_CMDR_RSPTYP_136BIT;
 346                 else
 347                         cmdr |= MCI_CMDR_RSPTYP_48BIT;
 348         }
 349
 350         /*
 351          * This should really be MAXLAT_5 for CMD2 and ACMD41, but
 352          * it's too difficult to determine whether this is an ACMD or
 353          * not. Better make it 64.
 354          */
 355         cmdr |= MCI_CMDR_MAXLAT_64CYC;
 356
 357         if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
 358                 cmdr |= MCI_CMDR_OPDCMD;
 359
 360         data = cmd->data;
 361         if (data) {
 362                 cmdr |= MCI_CMDR_START_XFER;
 363                 if (data->flags & MMC_DATA_STREAM)
 364                         cmdr |= MCI_CMDR_STREAM;
 365                 else if (data->blocks > 1)
 366                         cmdr |= MCI_CMDR_MULTI_BLOCK;
 367                 else
 368                         cmdr |= MCI_CMDR_BLOCK;
 369
 370                 if (data->flags & MMC_DATA_READ)
 371                         cmdr |= MCI_CMDR_TRDIR_READ;
 372         }
 373
 374         return cmdr;
 375 }
 376
 377 static void atmci_start_command(struct atmel_mci *host,
 378                                 struct mmc_command *cmd,
 379                                 u32 cmd_flags)
 380 {
 381         /* Must read host->cmd after testing event flags */
 382         smp_rmb();
 383         WARN_ON(host->cmd);
 384         host->cmd = cmd;
 385
 386         dev_vdbg(&host->mmc->class_dev,
 387                         "start command: ARGR=0x%08x CMDR=0x%08x\n",
 388                         cmd->arg, cmd_flags);
 389
 390         mci_writel(host, ARGR, cmd->arg);
 391         mci_writel(host, CMDR, cmd_flags);
 392 }
 393
 394 static void send_stop_cmd(struct mmc_host *mmc, struct mmc_data *data)
 395 {
 396         struct atmel_mci *host = mmc_priv(mmc);
 397
 398         atmci_start_command(host, data->stop, host->stop_cmdr);
 399         mci_writel(host, IER, MCI_CMDRDY);
 400 }
 401
 402 static void atmci_request_end(struct mmc_host *mmc, struct mmc_request *mrq)
 403 {
 404         struct atmel_mci *host = mmc_priv(mmc);
 405
 406         WARN_ON(host->cmd || host->data);
 407         host->mrq = NULL;
 408
 409         atmci_disable(host);
 410
 411         mmc_request_done(mmc, mrq);
 412 }
 413
 414 /*
 415  * Returns a mask of interrupt flags to be enabled after the whole
 416  * request has been prepared.
 417  */
 418 static u32 atmci_submit_data(struct mmc_host *mmc, struct mmc_data *data)
 419 {
 420         struct atmel_mci        *host = mmc_priv(mmc);
 421         u32                     iflags;
 422
 423         data->error = -EINPROGRESS;
 424
 425         WARN_ON(host->data);
 426         host->sg = NULL;
 427         host->data = data;
 428
 429         mci_writel(host, BLKR, MCI_BCNT(data->blocks)
 430                         | MCI_BLKLEN(data->blksz));
 431         dev_vdbg(&mmc->class_dev, "BLKR=0x%08x\n",
 432                         MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz));
 433
 434         iflags = ATMCI_DATA_ERROR_FLAGS;
 435         host->sg = data->sg;
 436         host->pio_offset = 0;
 437         if (data->flags & MMC_DATA_READ)
 438                 iflags |= MCI_RXRDY;
 439         else
 440                 iflags |= MCI_TXRDY;
 441
 442         return iflags;
 443 }
 444
 445 static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
 446 {
 447         struct atmel_mci        *host = mmc_priv(mmc);
 448         struct mmc_data         *data;
 449         struct mmc_command      *cmd;
 450         u32                     iflags;
 451         u32                     cmdflags = 0;
 452
 453         iflags = mci_readl(host, IMR);
 454         if (iflags)
 455                 dev_warn(&mmc->class_dev, "WARNING: IMR=0x%08x\n",
 456                                 mci_readl(host, IMR));
 457
 458         WARN_ON(host->mrq != NULL);
 459
 460         /*
 461          * We may "know" the card is gone even though there's still an
 462          * electrical connection. If so, we really need to communicate
 463          * this to the MMC core since there won't be any more
 464          * interrupts as the card is completely removed. Otherwise,
 465          * the MMC core might believe the card is still there even
 466          * though the card was just removed very slowly.
 467          */
 468         if (!host->present) {
 469                 mrq->cmd->error = -ENOMEDIUM;
 470                 mmc_request_done(mmc, mrq);
 471                 return;
 472         }
 473
 474         host->mrq = mrq;
 475         host->pending_events = 0;
 476         host->completed_events = 0;
 477
 478         atmci_enable(host);
 479
 480         /* We don't support multiple blocks of weird lengths. */
 481         data = mrq->data;
 482         if (data) {
 483                 if (data->blocks > 1 && data->blksz & 3)
 484                         goto fail;
 485                 atmci_set_timeout(host, data);
 486         }
 487
 488         iflags = MCI_CMDRDY;
 489         cmd = mrq->cmd;
 490         cmdflags = atmci_prepare_command(mmc, cmd);
 491         atmci_start_command(host, cmd, cmdflags);
 492
 493         if (data)
 494                 iflags |= atmci_submit_data(mmc, data);
 495
 496         if (mrq->stop) {
 497                 host->stop_cmdr = atmci_prepare_command(mmc, mrq->stop);
 498                 host->stop_cmdr |= MCI_CMDR_STOP_XFER;
 499                 if (!(data->flags & MMC_DATA_WRITE))
 500                         host->stop_cmdr |= MCI_CMDR_TRDIR_READ;
 501                 if (data->flags & MMC_DATA_STREAM)
 502                         host->stop_cmdr |= MCI_CMDR_STREAM;
 503                 else
 504                         host->stop_cmdr |= MCI_CMDR_MULTI_BLOCK;
 505         }
 506
 507         /*
 508          * We could have enabled interrupts earlier, but I suspect
 509          * that would open up a nice can of interesting race
 510          * conditions (e.g. command and data complete, but stop not
 511          * prepared yet.)
 512          */
 513         mci_writel(host, IER, iflags);
 514
 515         return;
 516
 517 fail:
 518         atmci_disable(host);
 519         host->mrq = NULL;
 520         mrq->cmd->error = -EINVAL;
 521         mmc_request_done(mmc, mrq);
 522 }
 523
 524 static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 525 {
 526         struct atmel_mci        *host = mmc_priv(mmc);
 527
 528         if (ios->clock) {
 529                 u32 clkdiv;
 530
 531                 /* Set clock rate */
 532                 clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * ios->clock) - 1;
 533                 if (clkdiv > 255) {
 534                         dev_warn(&mmc->class_dev,
 535                                 "clock %u too slow; using %lu\n",
 536                                 ios->clock, host->bus_hz / (2 * 256));
 537                         clkdiv = 255;
 538                 }
 539
 540                 host->mode_reg = MCI_MR_CLKDIV(clkdiv) | MCI_MR_WRPROOF
 541                                         | MCI_MR_RDPROOF;
 542         }
 543
 544         switch (ios->bus_width) {
 545         case MMC_BUS_WIDTH_1:
 546                 host->sdc_reg = 0;
 547                 break;
 548         case MMC_BUS_WIDTH_4:
 549                 host->sdc_reg = MCI_SDCBUS_4BIT;
 550                 break;
 551         }
 552
 553         switch (ios->power_mode) {
 554         case MMC_POWER_ON:
 555                 /* Send init sequence (74 clock cycles) */
 556                 atmci_enable(host);
 557                 mci_writel(host, CMDR, MCI_CMDR_SPCMD_INIT);
 558                 while (!(mci_readl(host, SR) & MCI_CMDRDY))
 559                         cpu_relax();
 560                 atmci_disable(host);
 561                 break;
 562         default:
 563                 /*
 564                  * TODO: None of the currently available AVR32-based
 565                  * boards allow MMC power to be turned off. Implement
 566                  * power control when this can be tested properly.
 567                  */
 568                 break;
 569         }
 570 }
 571
 572 static int atmci_get_ro(struct mmc_host *mmc)
 573 {
 574         int                     read_only = 0;
 575         struct atmel_mci        *host = mmc_priv(mmc);
 576
 577         if (gpio_is_valid(host->wp_pin)) {
 578                 read_only = gpio_get_value(host->wp_pin);
 579                 dev_dbg(&mmc->class_dev, "card is %s\n",
 580                                 read_only ? "read-only" : "read-write");
 581         } else {
 582                 dev_dbg(&mmc->class_dev,
 583                         "no pin for checking read-only switch."
 584                         " Assuming write-enable.\n");
 585         }
 586
 587         return read_only;
 588 }
 589
 590 static struct mmc_host_ops atmci_ops = {
 591         .request        = atmci_request,
 592         .set_ios        = atmci_set_ios,
 593         .get_ro         = atmci_get_ro,
 594 };
 595
 596 static void atmci_command_complete(struct atmel_mci *host,
 597                         struct mmc_command *cmd, u32 status)
 598 {
 599         /* Read the response from the card (up to 16 bytes) */
 600         cmd->resp[0] = mci_readl(host, RSPR);
 601         cmd->resp[1] = mci_readl(host, RSPR);
 602         cmd->resp[2] = mci_readl(host, RSPR);
 603         cmd->resp[3] = mci_readl(host, RSPR);
 604
 605         if (status & MCI_RTOE)
 606                 cmd->error = -ETIMEDOUT;
 607         else if ((cmd->flags & MMC_RSP_CRC) && (status & MCI_RCRCE))
 608                 cmd->error = -EILSEQ;
 609         else if (status & (MCI_RINDE | MCI_RDIRE | MCI_RENDE))
 610                 cmd->error = -EIO;
 611         else
 612                 cmd->error = 0;
 613
 614         if (cmd->error) {
 615                 dev_dbg(&host->mmc->class_dev,
 616                         "command error: status=0x%08x\n", status);
 617
 618                 if (cmd->data) {
 619                         host->data = NULL;
 620                         mci_writel(host, IDR, MCI_NOTBUSY
 621                                         | MCI_TXRDY | MCI_RXRDY
 622                                         | ATMCI_DATA_ERROR_FLAGS);
 623                 }
 624         }
 625 }
 626
 627 static void atmci_detect_change(unsigned long data)
 628 {
 629         struct atmel_mci *host = (struct atmel_mci *)data;
 630         struct mmc_request *mrq = host->mrq;
 631         int present;
 632
 633         /*
 634          * atmci_remove() sets detect_pin to -1 before freeing the
 635          * interrupt. We must not re-enable the interrupt if it has
 636          * been freed.
 637          */
 638         smp_rmb();
 639         if (!gpio_is_valid(host->detect_pin))
 640                 return;
 641
 642         enable_irq(gpio_to_irq(host->detect_pin));
 643         present = !gpio_get_value(host->detect_pin);
 644
 645         dev_vdbg(&host->pdev->dev, "detect change: %d (was %d)\n",
 646                         present, host->present);
 647
 648         if (present != host->present) {
 649                 dev_dbg(&host->mmc->class_dev, "card %s\n",
 650                         present ? "inserted" : "removed");
 651                 host->present = present;
 652
 653                 /* Reset controller if card is gone */
 654                 if (!present) {
 655                         mci_writel(host, CR, MCI_CR_SWRST);
 656                         mci_writel(host, IDR, ~0UL);
 657                         mci_writel(host, CR, MCI_CR_MCIEN);
 658                 }
 659
 660                 /* Clean up queue if present */
 661                 if (mrq) {
 662                         /*
 663                          * Reset controller to terminate any ongoing
 664                          * commands or data transfers.
 665                          */
 666                         mci_writel(host, CR, MCI_CR_SWRST);
 667
 668                         if (!atmci_is_completed(host, EVENT_CMD_COMPLETE))
 669                                 mrq->cmd->error = -ENOMEDIUM;
 670
 671                         if (mrq->data && !atmci_is_completed(host,
 672                                                 EVENT_DATA_COMPLETE)) {
 673                                 host->data = NULL;
 674                                 mrq->data->error = -ENOMEDIUM;
 675                         }
 676                         if (mrq->stop && !atmci_is_completed(host,
 677                                                 EVENT_STOP_COMPLETE))
 678                                 mrq->stop->error = -ENOMEDIUM;
 679
 680                         host->cmd = NULL;
 681                         atmci_request_end(host->mmc, mrq);
 682                 }
 683
 684                 mmc_detect_change(host->mmc, 0);
 685         }
 686 }
 687
 688 static void atmci_tasklet_func(unsigned long priv)
 689 {
 690         struct mmc_host         *mmc = (struct mmc_host *)priv;
 691         struct atmel_mci        *host = mmc_priv(mmc);
 692         struct mmc_request      *mrq = host->mrq;
 693         struct mmc_data         *data = host->data;
 694
 695         dev_vdbg(&mmc->class_dev,
 696                 "tasklet: pending/completed/mask %lx/%lx/%x\n",
 697                 host->pending_events, host->completed_events,
 698                 mci_readl(host, IMR));
 699
 700         if (atmci_test_and_clear_pending(host, EVENT_CMD_COMPLETE)) {
 701                 /*
 702                  * host->cmd must be set to NULL before the interrupt
 703                  * handler sees EVENT_CMD_COMPLETE
 704                  */
 705                 host->cmd = NULL;
 706                 smp_wmb();
 707                 atmci_set_completed(host, EVENT_CMD_COMPLETE);
 708                 atmci_command_complete(host, mrq->cmd, host->cmd_status);
 709
 710                 if (!mrq->cmd->error && mrq->stop
 711                                 && atmci_is_completed(host, EVENT_XFER_COMPLETE)
 712                                 && !atmci_test_and_set_completed(host,
 713                                         EVENT_STOP_SENT))
 714                         send_stop_cmd(host->mmc, mrq->data);
 715         }
 716         if (atmci_test_and_clear_pending(host, EVENT_STOP_COMPLETE)) {
 717                 /*
 718                  * host->cmd must be set to NULL before the interrupt
 719                  * handler sees EVENT_STOP_COMPLETE
 720                  */
 721                 host->cmd = NULL;
 722                 smp_wmb();
 723                 atmci_set_completed(host, EVENT_STOP_COMPLETE);
 724                 atmci_command_complete(host, mrq->stop, host->stop_status);
 725         }
 726         if (atmci_test_and_clear_pending(host, EVENT_DATA_ERROR)) {
 727                 u32 status = host->data_status;
 728
 729                 dev_vdbg(&mmc->class_dev, "data error: status=%08x\n", status);
 730
 731                 atmci_set_completed(host, EVENT_DATA_ERROR);
 732                 atmci_set_completed(host, EVENT_DATA_COMPLETE);
 733
 734                 if (status & MCI_DTOE) {
 735                         dev_dbg(&mmc->class_dev,
 736                                         "data timeout error\n");
 737                         data->error = -ETIMEDOUT;
 738                 } else if (status & MCI_DCRCE) {
 739                         dev_dbg(&mmc->class_dev, "data CRC error\n");
 740                         data->error = -EILSEQ;
 741                 } else {
 742                         dev_dbg(&mmc->class_dev,
 743                                         "data FIFO error (status=%08x)\n",
 744                                         status);
 745                         data->error = -EIO;
 746                 }
 747
 748                 if (host->present && data->stop
 749                                 && atmci_is_completed(host, EVENT_CMD_COMPLETE)
 750                                 && !atmci_test_and_set_completed(
 751                                         host, EVENT_STOP_SENT))
 752                         send_stop_cmd(host->mmc, data);
 753
 754                 host->data = NULL;
 755         }
 756         if (atmci_test_and_clear_pending(host, EVENT_DATA_COMPLETE)) {
 757                 atmci_set_completed(host, EVENT_DATA_COMPLETE);
 758
 759                 if (!atmci_is_completed(host, EVENT_DATA_ERROR)) {
 760                         data->bytes_xfered = data->blocks * data->blksz;
 761                         data->error = 0;
 762                 }
 763
 764                 host->data = NULL;
 765         }
 766
 767         if (host->mrq && !host->cmd && !host->data)
 768                 atmci_request_end(mmc, host->mrq);
 769 }
 770
 771 static void atmci_read_data_pio(struct atmel_mci *host)
 772 {
 773         struct scatterlist      *sg = host->sg;
 774         void                    *buf = sg_virt(sg);
 775         unsigned int            offset = host->pio_offset;
 776         struct mmc_data         *data = host->data;
 777         u32                     value;
 778         u32                     status;
 779         unsigned int            nbytes = 0;
 780
 781         do {
 782                 value = mci_readl(host, RDR);
 783                 if (likely(offset + 4 <= sg->length)) {
 784                         put_unaligned(value, (u32 *)(buf + offset));
 785
 786                         offset += 4;
 787                         nbytes += 4;
 788
 789                         if (offset == sg->length) {
 790                                 host->sg = sg = sg_next(sg);
 791                                 if (!sg)
 792                                         goto done;
 793
 794                                 offset = 0;
 795                                 buf = sg_virt(sg);
 796                         }
 797                 } else {
 798                         unsigned int remaining = sg->length - offset;
 799                         memcpy(buf + offset, &value, remaining);
 800                         nbytes += remaining;
 801
 802                         flush_dcache_page(sg_page(sg));
 803                         host->sg = sg = sg_next(sg);
 804                         if (!sg)
 805                                 goto done;
 806
 807                         offset = 4 - remaining;
 808                         buf = sg_virt(sg);
 809                         memcpy(buf, (u8 *)&value + remaining, offset);
 810                         nbytes += offset;
 811                 }
 812
 813                 status = mci_readl(host, SR);
 814                 if (status & ATMCI_DATA_ERROR_FLAGS) {
 815                         mci_writel(host, IDR, (MCI_NOTBUSY | MCI_RXRDY
 816                                                 | ATMCI_DATA_ERROR_FLAGS));
 817                         host->data_status = status;
 818                         atmci_set_pending(host, EVENT_DATA_ERROR);
 819                         tasklet_schedule(&host->tasklet);
 820                         break;
 821                 }
 822         } while (status & MCI_RXRDY);
 823
 824         host->pio_offset = offset;
 825         data->bytes_xfered += nbytes;
 826
 827         return;
 828
 829 done:
 830         mci_writel(host, IDR, MCI_RXRDY);
 831         mci_writel(host, IER, MCI_NOTBUSY);
 832         data->bytes_xfered += nbytes;
 833         atmci_set_completed(host, EVENT_XFER_COMPLETE);
 834         if (data->stop && atmci_is_completed(host, EVENT_CMD_COMPLETE)
 835                         && !atmci_test_and_set_completed(host, EVENT_STOP_SENT))
 836                 send_stop_cmd(host->mmc, data);
 837 }
 838
 839 static void atmci_write_data_pio(struct atmel_mci *host)
 840 {
 841         struct scatterlist      *sg = host->sg;
 842         void                    *buf = sg_virt(sg);
 843         unsigned int            offset = host->pio_offset;
 844         struct mmc_data         *data = host->data;
 845         u32                     value;
 846         u32                     status;
 847         unsigned int            nbytes = 0;
 848
 849         do {
 850                 if (likely(offset + 4 <= sg->length)) {
 851                         value = get_unaligned((u32 *)(buf + offset));
 852                         mci_writel(host, TDR, value);
 853
 854                         offset += 4;
 855                         nbytes += 4;
 856                         if (offset == sg->length) {
 857                                 host->sg = sg = sg_next(sg);
 858                                 if (!sg)
 859                                         goto done;
 860
 861                                 offset = 0;
 862                                 buf = sg_virt(sg);
 863                         }
 864                 } else {
 865                         unsigned int remaining = sg->length - offset;
 866
 867                         value = 0;
 868                         memcpy(&value, buf + offset, remaining);
 869                         nbytes += remaining;
 870
 871                         host->sg = sg = sg_next(sg);
 872                         if (!sg) {
 873                                 mci_writel(host, TDR, value);
 874                                 goto done;
 875                         }
 876
 877                         offset = 4 - remaining;
 878                         buf = sg_virt(sg);
 879                         memcpy((u8 *)&value + remaining, buf, offset);
 880                         mci_writel(host, TDR, value);
 881                         nbytes += offset;
 882                 }
 883
 884                 status = mci_readl(host, SR);
 885                 if (status & ATMCI_DATA_ERROR_FLAGS) {
 886                         mci_writel(host, IDR, (MCI_NOTBUSY | MCI_TXRDY
 887                                                 | ATMCI_DATA_ERROR_FLAGS));
 888                         host->data_status = status;
 889                         atmci_set_pending(host, EVENT_DATA_ERROR);
 890                         tasklet_schedule(&host->tasklet);
 891                         break;
 892                 }
 893         } while (status & MCI_TXRDY);
 894
 895         host->pio_offset = offset;
 896         data->bytes_xfered += nbytes;
 897
 898         return;
 899
 900 done:
 901         mci_writel(host, IDR, MCI_TXRDY);
 902         mci_writel(host, IER, MCI_NOTBUSY);
 903         data->bytes_xfered += nbytes;
 904         atmci_set_completed(host, EVENT_XFER_COMPLETE);
 905         if (data->stop && atmci_is_completed(host, EVENT_CMD_COMPLETE)
 906                         && !atmci_test_and_set_completed(host, EVENT_STOP_SENT))
 907                 send_stop_cmd(host->mmc, data);
 908 }
 909
 910 static void atmci_cmd_interrupt(struct mmc_host *mmc, u32 status)
 911 {
 912         struct atmel_mci        *host = mmc_priv(mmc);
 913
 914         mci_writel(host, IDR, MCI_CMDRDY);
 915
 916         if (atmci_is_completed(host, EVENT_STOP_SENT)) {
 917                 host->stop_status = status;
 918                 atmci_set_pending(host, EVENT_STOP_COMPLETE);
 919         } else {
 920                 host->cmd_status = status;
 921                 atmci_set_pending(host, EVENT_CMD_COMPLETE);
 922         }
 923
 924         tasklet_schedule(&host->tasklet);
 925 }
 926
 927 static irqreturn_t atmci_interrupt(int irq, void *dev_id)
 928 {
 929         struct mmc_host         *mmc = dev_id;
 930         struct atmel_mci        *host = mmc_priv(mmc);
 931         u32                     status, mask, pending;
 932         unsigned int            pass_count = 0;
 933
 934         spin_lock(&mmc->lock);
 935
 936         do {
 937                 status = mci_readl(host, SR);
 938                 mask = mci_readl(host, IMR);
 939                 pending = status & mask;
 940                 if (!pending)
 941                         break;
 942
 943                 if (pending & ATMCI_DATA_ERROR_FLAGS) {
 944                         mci_writel(host, IDR, ATMCI_DATA_ERROR_FLAGS
 945                                         | MCI_RXRDY | MCI_TXRDY);
 946                         pending &= mci_readl(host, IMR);
 947                         host->data_status = status;
 948                         atmci_set_pending(host, EVENT_DATA_ERROR);
 949                         tasklet_schedule(&host->tasklet);
 950                 }
 951                 if (pending & MCI_NOTBUSY) {
 952                         mci_writel(host, IDR, (MCI_NOTBUSY
 953                                                | ATMCI_DATA_ERROR_FLAGS));
 954                         atmci_set_pending(host, EVENT_DATA_COMPLETE);
 955                         tasklet_schedule(&host->tasklet);
 956                 }
 957                 if (pending & MCI_RXRDY)
 958                         atmci_read_data_pio(host);
 959                 if (pending & MCI_TXRDY)
 960                         atmci_write_data_pio(host);
 961
 962                 if (pending & MCI_CMDRDY)
 963                         atmci_cmd_interrupt(mmc, status);
 964         } while (pass_count++ < 5);
 965
 966         spin_unlock(&mmc->lock);
 967
 968         return pass_count ? IRQ_HANDLED : IRQ_NONE;
 969 }
 970
 971 static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
 972 {
 973         struct mmc_host         *mmc = dev_id;
 974         struct atmel_mci        *host = mmc_priv(mmc);
 975
 976         /*
 977          * Disable interrupts until the pin has stabilized and check
 978          * the state then. Use mod_timer() since we may be in the
 979          * middle of the timer routine when this interrupt triggers.
 980          */
 981         disable_irq_nosync(irq);
 982         mod_timer(&host->detect_timer, jiffies + msecs_to_jiffies(20));
 983
 984         return IRQ_HANDLED;
 985 }
 986
 987 static int __init atmci_probe(struct platform_device *pdev)
 988 {
 989         struct mci_platform_data        *pdata;
 990         struct atmel_mci *host;
 991         struct mmc_host *mmc;
 992         struct resource *regs;
 993         int irq;
 994         int ret;
 995
 996         regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 997         if (!regs)
 998                 return -ENXIO;
 999         pdata = pdev->dev.platform_data;
1000         if (!pdata)
1001                 return -ENXIO;
1002         irq = platform_get_irq(pdev, 0);
1003         if (irq < 0)
1004                 return irq;
1005
1006         mmc = mmc_alloc_host(sizeof(struct atmel_mci), &pdev->dev);
1007         if (!mmc)
1008                 return -ENOMEM;
1009
1010         host = mmc_priv(mmc);
1011         host->pdev = pdev;
1012         host->mmc = mmc;
1013         host->detect_pin = pdata->detect_pin;
1014         host->wp_pin = pdata->wp_pin;
1015
1016         host->mck = clk_get(&pdev->dev, "mci_clk");
1017         if (IS_ERR(host->mck)) {
1018                 ret = PTR_ERR(host->mck);
1019                 goto err_clk_get;
1020         }
1021
1022         ret = -ENOMEM;
1023         host->regs = ioremap(regs->start, regs->end - regs->start + 1);
1024         if (!host->regs)
1025                 goto err_ioremap;
1026
1027         clk_enable(host->mck);
1028         mci_writel(host, CR, MCI_CR_SWRST);
1029         host->bus_hz = clk_get_rate(host->mck);
1030         clk_disable(host->mck);
1031
1032         host->mapbase = regs->start;
1033
1034         mmc->ops = &atmci_ops;
1035         mmc->f_min = (host->bus_hz + 511) / 512;
1036         mmc->f_max = host->bus_hz / 2;
1037         mmc->ocr_avail  = MMC_VDD_32_33 | MMC_VDD_33_34;
1038         mmc->caps |= MMC_CAP_4_BIT_DATA;
1039
1040         mmc->max_hw_segs = 64;
1041         mmc->max_phys_segs = 64;
1042         mmc->max_req_size = 32768 * 512;
1043         mmc->max_blk_size = 32768;
1044         mmc->max_blk_count = 512;
1045
1046         tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)mmc);
1047
1048         ret = request_irq(irq, atmci_interrupt, 0, pdev->dev.bus_id, mmc);
1049         if (ret)
1050                 goto err_request_irq;
1051
1052         /* Assume card is present if we don't have a detect pin */
1053         host->present = 1;
1054         if (gpio_is_valid(host->detect_pin)) {
1055                 if (gpio_request(host->detect_pin, "mmc_detect")) {
1056                         dev_dbg(&mmc->class_dev, "no detect pin available\n");
1057                         host->detect_pin = -1;
1058                 } else {
1059                         host->present = !gpio_get_value(host->detect_pin);
1060                 }
1061         }
1062
1063         if (!gpio_is_valid(host->detect_pin))
1064                 mmc->caps |= MMC_CAP_NEEDS_POLL;
1065
1066         if (gpio_is_valid(host->wp_pin)) {
1067                 if (gpio_request(host->wp_pin, "mmc_wp")) {
1068                         dev_dbg(&mmc->class_dev, "no WP pin available\n");
1069                         host->wp_pin = -1;
1070                 }
1071         }
1072
1073         platform_set_drvdata(pdev, host);
1074
1075         mmc_add_host(mmc);
1076
1077         if (gpio_is_valid(host->detect_pin)) {
1078                 setup_timer(&host->detect_timer, atmci_detect_change,
1079                                 (unsigned long)host);
1080
1081                 ret = request_irq(gpio_to_irq(host->detect_pin),
1082                                 atmci_detect_interrupt,
1083                                 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
1084                                 "mmc-detect", mmc);
1085                 if (ret) {
1086                         dev_dbg(&mmc->class_dev,
1087                                 "could not request IRQ %d for detect pin\n",
1088                                 gpio_to_irq(host->detect_pin));
1089                         gpio_free(host->detect_pin);
1090                         host->detect_pin = -1;
1091                 }
1092         }
1093
1094         dev_info(&mmc->class_dev,
1095                         "Atmel MCI controller at 0x%08lx irq %d\n",
1096                         host->mapbase, irq);
1097
1098         atmci_init_debugfs(host);
1099
1100         return 0;
1101
1102 err_request_irq:
1103         iounmap(host->regs);
1104 err_ioremap:
1105         clk_put(host->mck);
1106 err_clk_get:
1107         mmc_free_host(mmc);
1108         return ret;
1109 }
1110
1111 static int __exit atmci_remove(struct platform_device *pdev)
1112 {
1113         struct atmel_mci *host = platform_get_drvdata(pdev);
1114
1115         platform_set_drvdata(pdev, NULL);
1116
1117         if (host) {
1118                 /* Debugfs stuff is cleaned up by mmc core */
1119
1120                 if (gpio_is_valid(host->detect_pin)) {
1121                         int pin = host->detect_pin;
1122
1123                         /* Make sure the timer doesn't enable the interrupt */
1124                         host->detect_pin = -1;
1125                         smp_wmb();
1126
1127                         free_irq(gpio_to_irq(pin), host->mmc);
1128                         del_timer_sync(&host->detect_timer);
1129                         gpio_free(pin);
1130                 }
1131
1132                 mmc_remove_host(host->mmc);
1133
1134                 clk_enable(host->mck);
1135                 mci_writel(host, IDR, ~0UL);
1136                 mci_writel(host, CR, MCI_CR_MCIDIS);
1137                 mci_readl(host, SR);
1138                 clk_disable(host->mck);
1139
1140                 if (gpio_is_valid(host->wp_pin))
1141                         gpio_free(host->wp_pin);
1142
1143                 free_irq(platform_get_irq(pdev, 0), host->mmc);
1144                 iounmap(host->regs);
1145
1146                 clk_put(host->mck);
1147
1148                 mmc_free_host(host->mmc);
1149         }
1150         return 0;
1151 }
1152
1153 static struct platform_driver atmci_driver = {
1154         .remove         = __exit_p(atmci_remove),
1155         .driver         = {
1156                 .name           = "atmel_mci",
1157         },
1158 };
1159
1160 static int __init atmci_init(void)
1161 {
1162         return platform_driver_probe(&atmci_driver, atmci_probe);
1163 }
1164
1165 static void __exit atmci_exit(void)
1166 {
1167         platform_driver_unregister(&atmci_driver);
1168 }
1169
1170 module_init(atmci_init);
1171 module_exit(atmci_exit);
1172
1173 MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
1174 MODULE_AUTHOR("Haavard Skinnemoen <haavard.skinnemoen@atmel.com>");
1175 MODULE_LICENSE("GPL v2");