SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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         struct resource *res;
 245
 246         mmc = host->mmc;
 247         root = mmc->debugfs_root;
 248         if (!root)
 249                 return;
 250
 251         node = debugfs_create_file("regs", S_IRUSR, root, host,
 252                         &atmci_regs_fops);
 253         if (IS_ERR(node))
 254                 return;
 255         if (!node)
 256                 goto err;
 257
 258         res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);
 259         node->d_inode->i_size = res->end - res->start + 1;
 260
 261         node = debugfs_create_file("req", S_IRUSR, root, host, &atmci_req_fops);
 262         if (!node)
 263                 goto err;
 264
 265         node = debugfs_create_x32("pending_events", S_IRUSR, root,
 266                                      (u32 *)&host->pending_events);
 267         if (!node)
 268                 goto err;
 269
 270         node = debugfs_create_x32("completed_events", S_IRUSR, root,
 271                                      (u32 *)&host->completed_events);
 272         if (!node)
 273                 goto err;
 274
 275         return;
 276
 277 err:
 278         dev_err(&host->pdev->dev,
 279                 "failed to initialize debugfs for controller\n");
 280 }
 281
 282 static void atmci_enable(struct atmel_mci *host)
 283 {
 284         clk_enable(host->mck);
 285         mci_writel(host, CR, MCI_CR_MCIEN);
 286         mci_writel(host, MR, host->mode_reg);
 287         mci_writel(host, SDCR, host->sdc_reg);
 288 }
 289
 290 static void atmci_disable(struct atmel_mci *host)
 291 {
 292         mci_writel(host, CR, MCI_CR_SWRST);
 293
 294         /* Stall until write is complete, then disable the bus clock */
 295         mci_readl(host, SR);
 296         clk_disable(host->mck);
 297 }
 298
 299 static inline unsigned int ns_to_clocks(struct atmel_mci *host,
 300                                         unsigned int ns)
 301 {
 302         return (ns * (host->bus_hz / 1000000) + 999) / 1000;
 303 }
 304
 305 static void atmci_set_timeout(struct atmel_mci *host,
 306                               struct mmc_data *data)
 307 {
 308         static unsigned dtomul_to_shift[] = {
 309                 0, 4, 7, 8, 10, 12, 16, 20
 310         };
 311         unsigned        timeout;
 312         unsigned        dtocyc;
 313         unsigned        dtomul;
 314
 315         timeout = ns_to_clocks(host, data->timeout_ns) + data->timeout_clks;
 316
 317         for (dtomul = 0; dtomul < 8; dtomul++) {
 318                 unsigned shift = dtomul_to_shift[dtomul];
 319                 dtocyc = (timeout + (1 << shift) - 1) >> shift;
 320                 if (dtocyc < 15)
 321                         break;
 322         }
 323
 324         if (dtomul >= 8) {
 325                 dtomul = 7;
 326                 dtocyc = 15;
 327         }
 328
 329         dev_vdbg(&host->mmc->class_dev, "setting timeout to %u cycles\n",
 330                         dtocyc << dtomul_to_shift[dtomul]);
 331         mci_writel(host, DTOR, (MCI_DTOMUL(dtomul) | MCI_DTOCYC(dtocyc)));
 332 }
 333
 334 /*
 335  * Return mask with command flags to be enabled for this command.
 336  */
 337 static u32 atmci_prepare_command(struct mmc_host *mmc,
 338                                  struct mmc_command *cmd)
 339 {
 340         struct mmc_data *data;
 341         u32             cmdr;
 342
 343         cmd->error = -EINPROGRESS;
 344
 345         cmdr = MCI_CMDR_CMDNB(cmd->opcode);
 346
 347         if (cmd->flags & MMC_RSP_PRESENT) {
 348                 if (cmd->flags & MMC_RSP_136)
 349                         cmdr |= MCI_CMDR_RSPTYP_136BIT;
 350                 else
 351                         cmdr |= MCI_CMDR_RSPTYP_48BIT;
 352         }
 353
 354         /*
 355          * This should really be MAXLAT_5 for CMD2 and ACMD41, but
 356          * it's too difficult to determine whether this is an ACMD or
 357          * not. Better make it 64.
 358          */
 359         cmdr |= MCI_CMDR_MAXLAT_64CYC;
 360
 361         if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
 362                 cmdr |= MCI_CMDR_OPDCMD;
 363
 364         data = cmd->data;
 365         if (data) {
 366                 cmdr |= MCI_CMDR_START_XFER;
 367                 if (data->flags & MMC_DATA_STREAM)
 368                         cmdr |= MCI_CMDR_STREAM;
 369                 else if (data->blocks > 1)
 370                         cmdr |= MCI_CMDR_MULTI_BLOCK;
 371                 else
 372                         cmdr |= MCI_CMDR_BLOCK;
 373
 374                 if (data->flags & MMC_DATA_READ)
 375                         cmdr |= MCI_CMDR_TRDIR_READ;
 376         }
 377
 378         return cmdr;
 379 }
 380
 381 static void atmci_start_command(struct atmel_mci *host,
 382                                 struct mmc_command *cmd,
 383                                 u32 cmd_flags)
 384 {
 385         /* Must read host->cmd after testing event flags */
 386         smp_rmb();
 387         WARN_ON(host->cmd);
 388         host->cmd = cmd;
 389
 390         dev_vdbg(&host->mmc->class_dev,
 391                         "start command: ARGR=0x%08x CMDR=0x%08x\n",
 392                         cmd->arg, cmd_flags);
 393
 394         mci_writel(host, ARGR, cmd->arg);
 395         mci_writel(host, CMDR, cmd_flags);
 396 }
 397
 398 static void send_stop_cmd(struct mmc_host *mmc, struct mmc_data *data)
 399 {
 400         struct atmel_mci *host = mmc_priv(mmc);
 401
 402         atmci_start_command(host, data->stop, host->stop_cmdr);
 403         mci_writel(host, IER, MCI_CMDRDY);
 404 }
 405
 406 static void atmci_request_end(struct mmc_host *mmc, struct mmc_request *mrq)
 407 {
 408         struct atmel_mci *host = mmc_priv(mmc);
 409
 410         WARN_ON(host->cmd || host->data);
 411         host->mrq = NULL;
 412
 413         atmci_disable(host);
 414
 415         mmc_request_done(mmc, mrq);
 416 }
 417
 418 /*
 419  * Returns a mask of interrupt flags to be enabled after the whole
 420  * request has been prepared.
 421  */
 422 static u32 atmci_submit_data(struct mmc_host *mmc, struct mmc_data *data)
 423 {
 424         struct atmel_mci        *host = mmc_priv(mmc);
 425         u32                     iflags;
 426
 427         data->error = -EINPROGRESS;
 428
 429         WARN_ON(host->data);
 430         host->sg = NULL;
 431         host->data = data;
 432
 433         mci_writel(host, BLKR, MCI_BCNT(data->blocks)
 434                         | MCI_BLKLEN(data->blksz));
 435         dev_vdbg(&mmc->class_dev, "BLKR=0x%08x\n",
 436                         MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz));
 437
 438         iflags = ATMCI_DATA_ERROR_FLAGS;
 439         host->sg = data->sg;
 440         host->pio_offset = 0;
 441         if (data->flags & MMC_DATA_READ)
 442                 iflags |= MCI_RXRDY;
 443         else
 444                 iflags |= MCI_TXRDY;
 445
 446         return iflags;
 447 }
 448
 449 static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
 450 {
 451         struct atmel_mci        *host = mmc_priv(mmc);
 452         struct mmc_data         *data;
 453         struct mmc_command      *cmd;
 454         u32                     iflags;
 455         u32                     cmdflags = 0;
 456
 457         iflags = mci_readl(host, IMR);
 458         if (iflags)
 459                 dev_warn(&mmc->class_dev, "WARNING: IMR=0x%08x\n",
 460                                 mci_readl(host, IMR));
 461
 462         WARN_ON(host->mrq != NULL);
 463
 464         /*
 465          * We may "know" the card is gone even though there's still an
 466          * electrical connection. If so, we really need to communicate
 467          * this to the MMC core since there won't be any more
 468          * interrupts as the card is completely removed. Otherwise,
 469          * the MMC core might believe the card is still there even
 470          * though the card was just removed very slowly.
 471          */
 472         if (!host->present) {
 473                 mrq->cmd->error = -ENOMEDIUM;
 474                 mmc_request_done(mmc, mrq);
 475                 return;
 476         }
 477
 478         host->mrq = mrq;
 479         host->pending_events = 0;
 480         host->completed_events = 0;
 481
 482         atmci_enable(host);
 483
 484         /* We don't support multiple blocks of weird lengths. */
 485         data = mrq->data;
 486         if (data) {
 487                 if (data->blocks > 1 && data->blksz & 3)
 488                         goto fail;
 489                 atmci_set_timeout(host, data);
 490         }
 491
 492         iflags = MCI_CMDRDY;
 493         cmd = mrq->cmd;
 494         cmdflags = atmci_prepare_command(mmc, cmd);
 495         atmci_start_command(host, cmd, cmdflags);
 496
 497         if (data)
 498                 iflags |= atmci_submit_data(mmc, data);
 499
 500         if (mrq->stop) {
 501                 host->stop_cmdr = atmci_prepare_command(mmc, mrq->stop);
 502                 host->stop_cmdr |= MCI_CMDR_STOP_XFER;
 503                 if (!(data->flags & MMC_DATA_WRITE))
 504                         host->stop_cmdr |= MCI_CMDR_TRDIR_READ;
 505                 if (data->flags & MMC_DATA_STREAM)
 506                         host->stop_cmdr |= MCI_CMDR_STREAM;
 507                 else
 508                         host->stop_cmdr |= MCI_CMDR_MULTI_BLOCK;
 509         }
 510
 511         /*
 512          * We could have enabled interrupts earlier, but I suspect
 513          * that would open up a nice can of interesting race
 514          * conditions (e.g. command and data complete, but stop not
 515          * prepared yet.)
 516          */
 517         mci_writel(host, IER, iflags);
 518
 519         return;
 520
 521 fail:
 522         atmci_disable(host);
 523         host->mrq = NULL;
 524         mrq->cmd->error = -EINVAL;
 525         mmc_request_done(mmc, mrq);
 526 }
 527
 528 static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 529 {
 530         struct atmel_mci        *host = mmc_priv(mmc);
 531
 532         if (ios->clock) {
 533                 u32 clkdiv;
 534
 535                 /* Set clock rate */
 536                 clkdiv = DIV_ROUND_UP(host->bus_hz, 2 * ios->clock) - 1;
 537                 if (clkdiv > 255) {
 538                         dev_warn(&mmc->class_dev,
 539                                 "clock %u too slow; using %lu\n",
 540                                 ios->clock, host->bus_hz / (2 * 256));
 541                         clkdiv = 255;
 542                 }
 543
 544                 host->mode_reg = MCI_MR_CLKDIV(clkdiv) | MCI_MR_WRPROOF
 545                                         | MCI_MR_RDPROOF;
 546         }
 547
 548         switch (ios->bus_width) {
 549         case MMC_BUS_WIDTH_1:
 550                 host->sdc_reg = 0;
 551                 break;
 552         case MMC_BUS_WIDTH_4:
 553                 host->sdc_reg = MCI_SDCBUS_4BIT;
 554                 break;
 555         }
 556
 557         switch (ios->power_mode) {
 558         case MMC_POWER_ON:
 559                 /* Send init sequence (74 clock cycles) */
 560                 atmci_enable(host);
 561                 mci_writel(host, CMDR, MCI_CMDR_SPCMD_INIT);
 562                 while (!(mci_readl(host, SR) & MCI_CMDRDY))
 563                         cpu_relax();
 564                 atmci_disable(host);
 565                 break;
 566         default:
 567                 /*
 568                  * TODO: None of the currently available AVR32-based
 569                  * boards allow MMC power to be turned off. Implement
 570                  * power control when this can be tested properly.
 571                  */
 572                 break;
 573         }
 574 }
 575
 576 static int atmci_get_ro(struct mmc_host *mmc)
 577 {
 578         int                     read_only = 0;
 579         struct atmel_mci        *host = mmc_priv(mmc);
 580
 581         if (gpio_is_valid(host->wp_pin)) {
 582                 read_only = gpio_get_value(host->wp_pin);
 583                 dev_dbg(&mmc->class_dev, "card is %s\n",
 584                                 read_only ? "read-only" : "read-write");
 585         } else {
 586                 dev_dbg(&mmc->class_dev,
 587                         "no pin for checking read-only switch."
 588                         " Assuming write-enable.\n");
 589         }
 590
 591         return read_only;
 592 }
 593
 594 static struct mmc_host_ops atmci_ops = {
 595         .request        = atmci_request,
 596         .set_ios        = atmci_set_ios,
 597         .get_ro         = atmci_get_ro,
 598 };
 599
 600 static void atmci_command_complete(struct atmel_mci *host,
 601                         struct mmc_command *cmd, u32 status)
 602 {
 603         /* Read the response from the card (up to 16 bytes) */
 604         cmd->resp[0] = mci_readl(host, RSPR);
 605         cmd->resp[1] = mci_readl(host, RSPR);
 606         cmd->resp[2] = mci_readl(host, RSPR);
 607         cmd->resp[3] = mci_readl(host, RSPR);
 608
 609         if (status & MCI_RTOE)
 610                 cmd->error = -ETIMEDOUT;
 611         else if ((cmd->flags & MMC_RSP_CRC) && (status & MCI_RCRCE))
 612                 cmd->error = -EILSEQ;
 613         else if (status & (MCI_RINDE | MCI_RDIRE | MCI_RENDE))
 614                 cmd->error = -EIO;
 615         else
 616                 cmd->error = 0;
 617
 618         if (cmd->error) {
 619                 dev_dbg(&host->mmc->class_dev,
 620                         "command error: status=0x%08x\n", status);
 621
 622                 if (cmd->data) {
 623                         host->data = NULL;
 624                         mci_writel(host, IDR, MCI_NOTBUSY
 625                                         | MCI_TXRDY | MCI_RXRDY
 626                                         | ATMCI_DATA_ERROR_FLAGS);
 627                 }
 628         }
 629 }
 630
 631 static void atmci_detect_change(unsigned long data)
 632 {
 633         struct atmel_mci *host = (struct atmel_mci *)data;
 634         struct mmc_request *mrq = host->mrq;
 635         int present;
 636
 637         /*
 638          * atmci_remove() sets detect_pin to -1 before freeing the
 639          * interrupt. We must not re-enable the interrupt if it has
 640          * been freed.
 641          */
 642         smp_rmb();
 643         if (!gpio_is_valid(host->detect_pin))
 644                 return;
 645
 646         enable_irq(gpio_to_irq(host->detect_pin));
 647         present = !gpio_get_value(host->detect_pin);
 648
 649         dev_vdbg(&host->pdev->dev, "detect change: %d (was %d)\n",
 650                         present, host->present);
 651
 652         if (present != host->present) {
 653                 dev_dbg(&host->mmc->class_dev, "card %s\n",
 654                         present ? "inserted" : "removed");
 655                 host->present = present;
 656
 657                 /* Reset controller if card is gone */
 658                 if (!present) {
 659                         mci_writel(host, CR, MCI_CR_SWRST);
 660                         mci_writel(host, IDR, ~0UL);
 661                         mci_writel(host, CR, MCI_CR_MCIEN);
 662                 }
 663
 664                 /* Clean up queue if present */
 665                 if (mrq) {
 666                         /*
 667                          * Reset controller to terminate any ongoing
 668                          * commands or data transfers.
 669                          */
 670                         mci_writel(host, CR, MCI_CR_SWRST);
 671
 672                         if (!atmci_is_completed(host, EVENT_CMD_COMPLETE))
 673                                 mrq->cmd->error = -ENOMEDIUM;
 674
 675                         if (mrq->data && !atmci_is_completed(host,
 676                                                 EVENT_DATA_COMPLETE)) {
 677                                 host->data = NULL;
 678                                 mrq->data->error = -ENOMEDIUM;
 679                         }
 680                         if (mrq->stop && !atmci_is_completed(host,
 681                                                 EVENT_STOP_COMPLETE))
 682                                 mrq->stop->error = -ENOMEDIUM;
 683
 684                         host->cmd = NULL;
 685                         atmci_request_end(host->mmc, mrq);
 686                 }
 687
 688                 mmc_detect_change(host->mmc, 0);
 689         }
 690 }
 691
 692 static void atmci_tasklet_func(unsigned long priv)
 693 {
 694         struct mmc_host         *mmc = (struct mmc_host *)priv;
 695         struct atmel_mci        *host = mmc_priv(mmc);
 696         struct mmc_request      *mrq = host->mrq;
 697         struct mmc_data         *data = host->data;
 698
 699         dev_vdbg(&mmc->class_dev,
 700                 "tasklet: pending/completed/mask %lx/%lx/%x\n",
 701                 host->pending_events, host->completed_events,
 702                 mci_readl(host, IMR));
 703
 704         if (atmci_test_and_clear_pending(host, EVENT_CMD_COMPLETE)) {
 705                 /*
 706                  * host->cmd must be set to NULL before the interrupt
 707                  * handler sees EVENT_CMD_COMPLETE
 708                  */
 709                 host->cmd = NULL;
 710                 smp_wmb();
 711                 atmci_set_completed(host, EVENT_CMD_COMPLETE);
 712                 atmci_command_complete(host, mrq->cmd, host->cmd_status);
 713
 714                 if (!mrq->cmd->error && mrq->stop
 715                                 && atmci_is_completed(host, EVENT_XFER_COMPLETE)
 716                                 && !atmci_test_and_set_completed(host,
 717                                         EVENT_STOP_SENT))
 718                         send_stop_cmd(host->mmc, mrq->data);
 719         }
 720         if (atmci_test_and_clear_pending(host, EVENT_STOP_COMPLETE)) {
 721                 /*
 722                  * host->cmd must be set to NULL before the interrupt
 723                  * handler sees EVENT_STOP_COMPLETE
 724                  */
 725                 host->cmd = NULL;
 726                 smp_wmb();
 727                 atmci_set_completed(host, EVENT_STOP_COMPLETE);
 728                 atmci_command_complete(host, mrq->stop, host->stop_status);
 729         }
 730         if (atmci_test_and_clear_pending(host, EVENT_DATA_ERROR)) {
 731                 u32 status = host->data_status;
 732
 733                 dev_vdbg(&mmc->class_dev, "data error: status=%08x\n", status);
 734
 735                 atmci_set_completed(host, EVENT_DATA_ERROR);
 736                 atmci_set_completed(host, EVENT_DATA_COMPLETE);
 737
 738                 if (status & MCI_DTOE) {
 739                         dev_dbg(&mmc->class_dev,
 740                                         "data timeout error\n");
 741                         data->error = -ETIMEDOUT;
 742                 } else if (status & MCI_DCRCE) {
 743                         dev_dbg(&mmc->class_dev, "data CRC error\n");
 744                         data->error = -EILSEQ;
 745                 } else {
 746                         dev_dbg(&mmc->class_dev,
 747                                         "data FIFO error (status=%08x)\n",
 748                                         status);
 749                         data->error = -EIO;
 750                 }
 751
 752                 if (host->present && data->stop
 753                                 && atmci_is_completed(host, EVENT_CMD_COMPLETE)
 754                                 && !atmci_test_and_set_completed(
 755                                         host, EVENT_STOP_SENT))
 756                         send_stop_cmd(host->mmc, data);
 757
 758                 host->data = NULL;
 759         }
 760         if (atmci_test_and_clear_pending(host, EVENT_DATA_COMPLETE)) {
 761                 atmci_set_completed(host, EVENT_DATA_COMPLETE);
 762
 763                 if (!atmci_is_completed(host, EVENT_DATA_ERROR)) {
 764                         data->bytes_xfered = data->blocks * data->blksz;
 765                         data->error = 0;
 766                 }
 767
 768                 host->data = NULL;
 769         }
 770
 771         if (host->mrq && !host->cmd && !host->data)
 772                 atmci_request_end(mmc, host->mrq);
 773 }
 774
 775 static void atmci_read_data_pio(struct atmel_mci *host)
 776 {
 777         struct scatterlist      *sg = host->sg;
 778         void                    *buf = sg_virt(sg);
 779         unsigned int            offset = host->pio_offset;
 780         struct mmc_data         *data = host->data;
 781         u32                     value;
 782         u32                     status;
 783         unsigned int            nbytes = 0;
 784
 785         do {
 786                 value = mci_readl(host, RDR);
 787                 if (likely(offset + 4 <= sg->length)) {
 788                         put_unaligned(value, (u32 *)(buf + offset));
 789
 790                         offset += 4;
 791                         nbytes += 4;
 792
 793                         if (offset == sg->length) {
 794                                 host->sg = sg = sg_next(sg);
 795                                 if (!sg)
 796                                         goto done;
 797
 798                                 offset = 0;
 799                                 buf = sg_virt(sg);
 800                         }
 801                 } else {
 802                         unsigned int remaining = sg->length - offset;
 803                         memcpy(buf + offset, &value, remaining);
 804                         nbytes += remaining;
 805
 806                         flush_dcache_page(sg_page(sg));
 807                         host->sg = sg = sg_next(sg);
 808                         if (!sg)
 809                                 goto done;
 810
 811                         offset = 4 - remaining;
 812                         buf = sg_virt(sg);
 813                         memcpy(buf, (u8 *)&value + remaining, offset);
 814                         nbytes += offset;
 815                 }
 816
 817                 status = mci_readl(host, SR);
 818                 if (status & ATMCI_DATA_ERROR_FLAGS) {
 819                         mci_writel(host, IDR, (MCI_NOTBUSY | MCI_RXRDY
 820                                                 | ATMCI_DATA_ERROR_FLAGS));
 821                         host->data_status = status;
 822                         atmci_set_pending(host, EVENT_DATA_ERROR);
 823                         tasklet_schedule(&host->tasklet);
 824                         break;
 825                 }
 826         } while (status & MCI_RXRDY);
 827
 828         host->pio_offset = offset;
 829         data->bytes_xfered += nbytes;
 830
 831         return;
 832
 833 done:
 834         mci_writel(host, IDR, MCI_RXRDY);
 835         mci_writel(host, IER, MCI_NOTBUSY);
 836         data->bytes_xfered += nbytes;
 837         atmci_set_completed(host, EVENT_XFER_COMPLETE);
 838         if (data->stop && atmci_is_completed(host, EVENT_CMD_COMPLETE)
 839                         && !atmci_test_and_set_completed(host, EVENT_STOP_SENT))
 840                 send_stop_cmd(host->mmc, data);
 841 }
 842
 843 static void atmci_write_data_pio(struct atmel_mci *host)
 844 {
 845         struct scatterlist      *sg = host->sg;
 846         void                    *buf = sg_virt(sg);
 847         unsigned int            offset = host->pio_offset;
 848         struct mmc_data         *data = host->data;
 849         u32                     value;
 850         u32                     status;
 851         unsigned int            nbytes = 0;
 852
 853         do {
 854                 if (likely(offset + 4 <= sg->length)) {
 855                         value = get_unaligned((u32 *)(buf + offset));
 856                         mci_writel(host, TDR, value);
 857
 858                         offset += 4;
 859                         nbytes += 4;
 860                         if (offset == sg->length) {
 861                                 host->sg = sg = sg_next(sg);
 862                                 if (!sg)
 863                                         goto done;
 864
 865                                 offset = 0;
 866                                 buf = sg_virt(sg);
 867                         }
 868                 } else {
 869                         unsigned int remaining = sg->length - offset;
 870
 871                         value = 0;
 872                         memcpy(&value, buf + offset, remaining);
 873                         nbytes += remaining;
 874
 875                         host->sg = sg = sg_next(sg);
 876                         if (!sg) {
 877                                 mci_writel(host, TDR, value);
 878                                 goto done;
 879                         }
 880
 881                         offset = 4 - remaining;
 882                         buf = sg_virt(sg);
 883                         memcpy((u8 *)&value + remaining, buf, offset);
 884                         mci_writel(host, TDR, value);
 885                         nbytes += offset;
 886                 }
 887
 888                 status = mci_readl(host, SR);
 889                 if (status & ATMCI_DATA_ERROR_FLAGS) {
 890                         mci_writel(host, IDR, (MCI_NOTBUSY | MCI_TXRDY
 891                                                 | ATMCI_DATA_ERROR_FLAGS));
 892                         host->data_status = status;
 893                         atmci_set_pending(host, EVENT_DATA_ERROR);
 894                         tasklet_schedule(&host->tasklet);
 895                         break;
 896                 }
 897         } while (status & MCI_TXRDY);
 898
 899         host->pio_offset = offset;
 900         data->bytes_xfered += nbytes;
 901
 902         return;
 903
 904 done:
 905         mci_writel(host, IDR, MCI_TXRDY);
 906         mci_writel(host, IER, MCI_NOTBUSY);
 907         data->bytes_xfered += nbytes;
 908         atmci_set_completed(host, EVENT_XFER_COMPLETE);
 909         if (data->stop && atmci_is_completed(host, EVENT_CMD_COMPLETE)
 910                         && !atmci_test_and_set_completed(host, EVENT_STOP_SENT))
 911                 send_stop_cmd(host->mmc, data);
 912 }
 913
 914 static void atmci_cmd_interrupt(struct mmc_host *mmc, u32 status)
 915 {
 916         struct atmel_mci        *host = mmc_priv(mmc);
 917
 918         mci_writel(host, IDR, MCI_CMDRDY);
 919
 920         if (atmci_is_completed(host, EVENT_STOP_SENT)) {
 921                 host->stop_status = status;
 922                 atmci_set_pending(host, EVENT_STOP_COMPLETE);
 923         } else {
 924                 host->cmd_status = status;
 925                 atmci_set_pending(host, EVENT_CMD_COMPLETE);
 926         }
 927
 928         tasklet_schedule(&host->tasklet);
 929 }
 930
 931 static irqreturn_t atmci_interrupt(int irq, void *dev_id)
 932 {
 933         struct mmc_host         *mmc = dev_id;
 934         struct atmel_mci        *host = mmc_priv(mmc);
 935         u32                     status, mask, pending;
 936         unsigned int            pass_count = 0;
 937
 938         spin_lock(&mmc->lock);
 939
 940         do {
 941                 status = mci_readl(host, SR);
 942                 mask = mci_readl(host, IMR);
 943                 pending = status & mask;
 944                 if (!pending)
 945                         break;
 946
 947                 if (pending & ATMCI_DATA_ERROR_FLAGS) {
 948                         mci_writel(host, IDR, ATMCI_DATA_ERROR_FLAGS
 949                                         | MCI_RXRDY | MCI_TXRDY);
 950                         pending &= mci_readl(host, IMR);
 951                         host->data_status = status;
 952                         atmci_set_pending(host, EVENT_DATA_ERROR);
 953                         tasklet_schedule(&host->tasklet);
 954                 }
 955                 if (pending & MCI_NOTBUSY) {
 956                         mci_writel(host, IDR, (MCI_NOTBUSY
 957                                                | ATMCI_DATA_ERROR_FLAGS));
 958                         atmci_set_pending(host, EVENT_DATA_COMPLETE);
 959                         tasklet_schedule(&host->tasklet);
 960                 }
 961                 if (pending & MCI_RXRDY)
 962                         atmci_read_data_pio(host);
 963                 if (pending & MCI_TXRDY)
 964                         atmci_write_data_pio(host);
 965
 966                 if (pending & MCI_CMDRDY)
 967                         atmci_cmd_interrupt(mmc, status);
 968         } while (pass_count++ < 5);
 969
 970         spin_unlock(&mmc->lock);
 971
 972         return pass_count ? IRQ_HANDLED : IRQ_NONE;
 973 }
 974
 975 static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
 976 {
 977         struct mmc_host         *mmc = dev_id;
 978         struct atmel_mci        *host = mmc_priv(mmc);
 979
 980         /*
 981          * Disable interrupts until the pin has stabilized and check
 982          * the state then. Use mod_timer() since we may be in the
 983          * middle of the timer routine when this interrupt triggers.
 984          */
 985         disable_irq_nosync(irq);
 986         mod_timer(&host->detect_timer, jiffies + msecs_to_jiffies(20));
 987
 988         return IRQ_HANDLED;
 989 }
 990
 991 static int __init atmci_probe(struct platform_device *pdev)
 992 {
 993         struct mci_platform_data        *pdata;
 994         struct atmel_mci *host;
 995         struct mmc_host *mmc;
 996         struct resource *regs;
 997         int irq;
 998         int ret;
 999
1000         regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1001         if (!regs)
1002                 return -ENXIO;
1003         pdata = pdev->dev.platform_data;
1004         if (!pdata)
1005                 return -ENXIO;
1006         irq = platform_get_irq(pdev, 0);
1007         if (irq < 0)
1008                 return irq;
1009
1010         mmc = mmc_alloc_host(sizeof(struct atmel_mci), &pdev->dev);
1011         if (!mmc)
1012                 return -ENOMEM;
1013
1014         host = mmc_priv(mmc);
1015         host->pdev = pdev;
1016         host->mmc = mmc;
1017         host->detect_pin = pdata->detect_pin;
1018         host->wp_pin = pdata->wp_pin;
1019
1020         host->mck = clk_get(&pdev->dev, "mci_clk");
1021         if (IS_ERR(host->mck)) {
1022                 ret = PTR_ERR(host->mck);
1023                 goto err_clk_get;
1024         }
1025
1026         ret = -ENOMEM;
1027         host->regs = ioremap(regs->start, regs->end - regs->start + 1);
1028         if (!host->regs)
1029                 goto err_ioremap;
1030
1031         clk_enable(host->mck);
1032         mci_writel(host, CR, MCI_CR_SWRST);
1033         host->bus_hz = clk_get_rate(host->mck);
1034         clk_disable(host->mck);
1035
1036         host->mapbase = regs->start;
1037
1038         mmc->ops = &atmci_ops;
1039         mmc->f_min = (host->bus_hz + 511) / 512;
1040         mmc->f_max = host->bus_hz / 2;
1041         mmc->ocr_avail  = MMC_VDD_32_33 | MMC_VDD_33_34;
1042         mmc->caps |= MMC_CAP_4_BIT_DATA;
1043
1044         mmc->max_hw_segs = 64;
1045         mmc->max_phys_segs = 64;
1046         mmc->max_req_size = 32768 * 512;
1047         mmc->max_blk_size = 32768;
1048         mmc->max_blk_count = 512;
1049
1050         tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)mmc);
1051
1052         ret = request_irq(irq, atmci_interrupt, 0, pdev->dev.bus_id, mmc);
1053         if (ret)
1054                 goto err_request_irq;
1055
1056         /* Assume card is present if we don't have a detect pin */
1057         host->present = 1;
1058         if (gpio_is_valid(host->detect_pin)) {
1059                 if (gpio_request(host->detect_pin, "mmc_detect")) {
1060                         dev_dbg(&mmc->class_dev, "no detect pin available\n");
1061                         host->detect_pin = -1;
1062                 } else {
1063                         host->present = !gpio_get_value(host->detect_pin);
1064                 }
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");