linux/drivers/mmc/host/omap.c
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   1/*
   2 *  linux/drivers/mmc/host/omap.c
   3 *
   4 *  Copyright (C) 2004 Nokia Corporation
   5 *  Written by Tuukka Tikkanen and Juha Yrjölä<juha.yrjola@nokia.com>
   6 *  Misc hacks here and there by Tony Lindgren <tony@atomide.com>
   7 *  Other hacks (DMA, SD, etc) by David Brownell
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 */
  13
  14#include <linux/module.h>
  15#include <linux/moduleparam.h>
  16#include <linux/init.h>
  17#include <linux/ioport.h>
  18#include <linux/platform_device.h>
  19#include <linux/interrupt.h>
  20#include <linux/dmaengine.h>
  21#include <linux/dma-mapping.h>
  22#include <linux/delay.h>
  23#include <linux/spinlock.h>
  24#include <linux/timer.h>
  25#include <linux/of.h>
  26#include <linux/omap-dma.h>
  27#include <linux/mmc/host.h>
  28#include <linux/mmc/card.h>
  29#include <linux/mmc/mmc.h>
  30#include <linux/clk.h>
  31#include <linux/scatterlist.h>
  32#include <linux/slab.h>
  33#include <linux/platform_data/mmc-omap.h>
  34
  35
  36#define OMAP_MMC_REG_CMD        0x00
  37#define OMAP_MMC_REG_ARGL       0x01
  38#define OMAP_MMC_REG_ARGH       0x02
  39#define OMAP_MMC_REG_CON        0x03
  40#define OMAP_MMC_REG_STAT       0x04
  41#define OMAP_MMC_REG_IE         0x05
  42#define OMAP_MMC_REG_CTO        0x06
  43#define OMAP_MMC_REG_DTO        0x07
  44#define OMAP_MMC_REG_DATA       0x08
  45#define OMAP_MMC_REG_BLEN       0x09
  46#define OMAP_MMC_REG_NBLK       0x0a
  47#define OMAP_MMC_REG_BUF        0x0b
  48#define OMAP_MMC_REG_SDIO       0x0d
  49#define OMAP_MMC_REG_REV        0x0f
  50#define OMAP_MMC_REG_RSP0       0x10
  51#define OMAP_MMC_REG_RSP1       0x11
  52#define OMAP_MMC_REG_RSP2       0x12
  53#define OMAP_MMC_REG_RSP3       0x13
  54#define OMAP_MMC_REG_RSP4       0x14
  55#define OMAP_MMC_REG_RSP5       0x15
  56#define OMAP_MMC_REG_RSP6       0x16
  57#define OMAP_MMC_REG_RSP7       0x17
  58#define OMAP_MMC_REG_IOSR       0x18
  59#define OMAP_MMC_REG_SYSC       0x19
  60#define OMAP_MMC_REG_SYSS       0x1a
  61
  62#define OMAP_MMC_STAT_CARD_ERR          (1 << 14)
  63#define OMAP_MMC_STAT_CARD_IRQ          (1 << 13)
  64#define OMAP_MMC_STAT_OCR_BUSY          (1 << 12)
  65#define OMAP_MMC_STAT_A_EMPTY           (1 << 11)
  66#define OMAP_MMC_STAT_A_FULL            (1 << 10)
  67#define OMAP_MMC_STAT_CMD_CRC           (1 <<  8)
  68#define OMAP_MMC_STAT_CMD_TOUT          (1 <<  7)
  69#define OMAP_MMC_STAT_DATA_CRC          (1 <<  6)
  70#define OMAP_MMC_STAT_DATA_TOUT         (1 <<  5)
  71#define OMAP_MMC_STAT_END_BUSY          (1 <<  4)
  72#define OMAP_MMC_STAT_END_OF_DATA       (1 <<  3)
  73#define OMAP_MMC_STAT_CARD_BUSY         (1 <<  2)
  74#define OMAP_MMC_STAT_END_OF_CMD        (1 <<  0)
  75
  76#define mmc_omap7xx()   (host->features & MMC_OMAP7XX)
  77#define mmc_omap15xx()  (host->features & MMC_OMAP15XX)
  78#define mmc_omap16xx()  (host->features & MMC_OMAP16XX)
  79#define MMC_OMAP1_MASK  (MMC_OMAP7XX | MMC_OMAP15XX | MMC_OMAP16XX)
  80#define mmc_omap1()     (host->features & MMC_OMAP1_MASK)
  81#define mmc_omap2()     (!mmc_omap1())
  82
  83#define OMAP_MMC_REG(host, reg)         (OMAP_MMC_REG_##reg << (host)->reg_shift)
  84#define OMAP_MMC_READ(host, reg)        __raw_readw((host)->virt_base + OMAP_MMC_REG(host, reg))
  85#define OMAP_MMC_WRITE(host, reg, val)  __raw_writew((val), (host)->virt_base + OMAP_MMC_REG(host, reg))
  86
  87/*
  88 * Command types
  89 */
  90#define OMAP_MMC_CMDTYPE_BC     0
  91#define OMAP_MMC_CMDTYPE_BCR    1
  92#define OMAP_MMC_CMDTYPE_AC     2
  93#define OMAP_MMC_CMDTYPE_ADTC   3
  94
  95#define DRIVER_NAME "mmci-omap"
  96
  97/* Specifies how often in millisecs to poll for card status changes
  98 * when the cover switch is open */
  99#define OMAP_MMC_COVER_POLL_DELAY       500
 100
 101struct mmc_omap_host;
 102
 103struct mmc_omap_slot {
 104        int                     id;
 105        unsigned int            vdd;
 106        u16                     saved_con;
 107        u16                     bus_mode;
 108        unsigned int            fclk_freq;
 109
 110        struct tasklet_struct   cover_tasklet;
 111        struct timer_list       cover_timer;
 112        unsigned                cover_open;
 113
 114        struct mmc_request      *mrq;
 115        struct mmc_omap_host    *host;
 116        struct mmc_host         *mmc;
 117        struct omap_mmc_slot_data *pdata;
 118};
 119
 120struct mmc_omap_host {
 121        int                     initialized;
 122        struct mmc_request *    mrq;
 123        struct mmc_command *    cmd;
 124        struct mmc_data *       data;
 125        struct mmc_host *       mmc;
 126        struct device *         dev;
 127        unsigned char           id; /* 16xx chips have 2 MMC blocks */
 128        struct clk *            iclk;
 129        struct clk *            fclk;
 130        struct dma_chan         *dma_rx;
 131        u32                     dma_rx_burst;
 132        struct dma_chan         *dma_tx;
 133        u32                     dma_tx_burst;
 134        void __iomem            *virt_base;
 135        unsigned int            phys_base;
 136        int                     irq;
 137        unsigned char           bus_mode;
 138        unsigned int            reg_shift;
 139
 140        struct work_struct      cmd_abort_work;
 141        unsigned                abort:1;
 142        struct timer_list       cmd_abort_timer;
 143
 144        struct work_struct      slot_release_work;
 145        struct mmc_omap_slot    *next_slot;
 146        struct work_struct      send_stop_work;
 147        struct mmc_data         *stop_data;
 148
 149        unsigned int            sg_len;
 150        int                     sg_idx;
 151        u16 *                   buffer;
 152        u32                     buffer_bytes_left;
 153        u32                     total_bytes_left;
 154
 155        unsigned                features;
 156        unsigned                brs_received:1, dma_done:1;
 157        unsigned                dma_in_use:1;
 158        spinlock_t              dma_lock;
 159
 160        struct mmc_omap_slot    *slots[OMAP_MMC_MAX_SLOTS];
 161        struct mmc_omap_slot    *current_slot;
 162        spinlock_t              slot_lock;
 163        wait_queue_head_t       slot_wq;
 164        int                     nr_slots;
 165
 166        struct timer_list       clk_timer;
 167        spinlock_t              clk_lock;     /* for changing enabled state */
 168        unsigned int            fclk_enabled:1;
 169        struct workqueue_struct *mmc_omap_wq;
 170
 171        struct omap_mmc_platform_data *pdata;
 172};
 173
 174
 175static void mmc_omap_fclk_offdelay(struct mmc_omap_slot *slot)
 176{
 177        unsigned long tick_ns;
 178
 179        if (slot != NULL && slot->host->fclk_enabled && slot->fclk_freq > 0) {
 180                tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
 181                ndelay(8 * tick_ns);
 182        }
 183}
 184
 185static void mmc_omap_fclk_enable(struct mmc_omap_host *host, unsigned int enable)
 186{
 187        unsigned long flags;
 188
 189        spin_lock_irqsave(&host->clk_lock, flags);
 190        if (host->fclk_enabled != enable) {
 191                host->fclk_enabled = enable;
 192                if (enable)
 193                        clk_enable(host->fclk);
 194                else
 195                        clk_disable(host->fclk);
 196        }
 197        spin_unlock_irqrestore(&host->clk_lock, flags);
 198}
 199
 200static void mmc_omap_select_slot(struct mmc_omap_slot *slot, int claimed)
 201{
 202        struct mmc_omap_host *host = slot->host;
 203        unsigned long flags;
 204
 205        if (claimed)
 206                goto no_claim;
 207        spin_lock_irqsave(&host->slot_lock, flags);
 208        while (host->mmc != NULL) {
 209                spin_unlock_irqrestore(&host->slot_lock, flags);
 210                wait_event(host->slot_wq, host->mmc == NULL);
 211                spin_lock_irqsave(&host->slot_lock, flags);
 212        }
 213        host->mmc = slot->mmc;
 214        spin_unlock_irqrestore(&host->slot_lock, flags);
 215no_claim:
 216        del_timer(&host->clk_timer);
 217        if (host->current_slot != slot || !claimed)
 218                mmc_omap_fclk_offdelay(host->current_slot);
 219
 220        if (host->current_slot != slot) {
 221                OMAP_MMC_WRITE(host, CON, slot->saved_con & 0xFC00);
 222                if (host->pdata->switch_slot != NULL)
 223                        host->pdata->switch_slot(mmc_dev(slot->mmc), slot->id);
 224                host->current_slot = slot;
 225        }
 226
 227        if (claimed) {
 228                mmc_omap_fclk_enable(host, 1);
 229
 230                /* Doing the dummy read here seems to work around some bug
 231                 * at least in OMAP24xx silicon where the command would not
 232                 * start after writing the CMD register. Sigh. */
 233                OMAP_MMC_READ(host, CON);
 234
 235                OMAP_MMC_WRITE(host, CON, slot->saved_con);
 236        } else
 237                mmc_omap_fclk_enable(host, 0);
 238}
 239
 240static void mmc_omap_start_request(struct mmc_omap_host *host,
 241                                   struct mmc_request *req);
 242
 243static void mmc_omap_slot_release_work(struct work_struct *work)
 244{
 245        struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
 246                                                  slot_release_work);
 247        struct mmc_omap_slot *next_slot = host->next_slot;
 248        struct mmc_request *rq;
 249
 250        host->next_slot = NULL;
 251        mmc_omap_select_slot(next_slot, 1);
 252
 253        rq = next_slot->mrq;
 254        next_slot->mrq = NULL;
 255        mmc_omap_start_request(host, rq);
 256}
 257
 258static void mmc_omap_release_slot(struct mmc_omap_slot *slot, int clk_enabled)
 259{
 260        struct mmc_omap_host *host = slot->host;
 261        unsigned long flags;
 262        int i;
 263
 264        BUG_ON(slot == NULL || host->mmc == NULL);
 265
 266        if (clk_enabled)
 267                /* Keeps clock running for at least 8 cycles on valid freq */
 268                mod_timer(&host->clk_timer, jiffies  + HZ/10);
 269        else {
 270                del_timer(&host->clk_timer);
 271                mmc_omap_fclk_offdelay(slot);
 272                mmc_omap_fclk_enable(host, 0);
 273        }
 274
 275        spin_lock_irqsave(&host->slot_lock, flags);
 276        /* Check for any pending requests */
 277        for (i = 0; i < host->nr_slots; i++) {
 278                struct mmc_omap_slot *new_slot;
 279
 280                if (host->slots[i] == NULL || host->slots[i]->mrq == NULL)
 281                        continue;
 282
 283                BUG_ON(host->next_slot != NULL);
 284                new_slot = host->slots[i];
 285                /* The current slot should not have a request in queue */
 286                BUG_ON(new_slot == host->current_slot);
 287
 288                host->next_slot = new_slot;
 289                host->mmc = new_slot->mmc;
 290                spin_unlock_irqrestore(&host->slot_lock, flags);
 291                queue_work(host->mmc_omap_wq, &host->slot_release_work);
 292                return;
 293        }
 294
 295        host->mmc = NULL;
 296        wake_up(&host->slot_wq);
 297        spin_unlock_irqrestore(&host->slot_lock, flags);
 298}
 299
 300static inline
 301int mmc_omap_cover_is_open(struct mmc_omap_slot *slot)
 302{
 303        if (slot->pdata->get_cover_state)
 304                return slot->pdata->get_cover_state(mmc_dev(slot->mmc),
 305                                                    slot->id);
 306        return 0;
 307}
 308
 309static ssize_t
 310mmc_omap_show_cover_switch(struct device *dev, struct device_attribute *attr,
 311                           char *buf)
 312{
 313        struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
 314        struct mmc_omap_slot *slot = mmc_priv(mmc);
 315
 316        return sprintf(buf, "%s\n", mmc_omap_cover_is_open(slot) ? "open" :
 317                       "closed");
 318}
 319
 320static DEVICE_ATTR(cover_switch, S_IRUGO, mmc_omap_show_cover_switch, NULL);
 321
 322static ssize_t
 323mmc_omap_show_slot_name(struct device *dev, struct device_attribute *attr,
 324                        char *buf)
 325{
 326        struct mmc_host *mmc = container_of(dev, struct mmc_host, class_dev);
 327        struct mmc_omap_slot *slot = mmc_priv(mmc);
 328
 329        return sprintf(buf, "%s\n", slot->pdata->name);
 330}
 331
 332static DEVICE_ATTR(slot_name, S_IRUGO, mmc_omap_show_slot_name, NULL);
 333
 334static void
 335mmc_omap_start_command(struct mmc_omap_host *host, struct mmc_command *cmd)
 336{
 337        u32 cmdreg;
 338        u32 resptype;
 339        u32 cmdtype;
 340        u16 irq_mask;
 341
 342        host->cmd = cmd;
 343
 344        resptype = 0;
 345        cmdtype = 0;
 346
 347        /* Our hardware needs to know exact type */
 348        switch (mmc_resp_type(cmd)) {
 349        case MMC_RSP_NONE:
 350                break;
 351        case MMC_RSP_R1:
 352        case MMC_RSP_R1B:
 353                /* resp 1, 1b, 6, 7 */
 354                resptype = 1;
 355                break;
 356        case MMC_RSP_R2:
 357                resptype = 2;
 358                break;
 359        case MMC_RSP_R3:
 360                resptype = 3;
 361                break;
 362        default:
 363                dev_err(mmc_dev(host->mmc), "Invalid response type: %04x\n", mmc_resp_type(cmd));
 364                break;
 365        }
 366
 367        if (mmc_cmd_type(cmd) == MMC_CMD_ADTC) {
 368                cmdtype = OMAP_MMC_CMDTYPE_ADTC;
 369        } else if (mmc_cmd_type(cmd) == MMC_CMD_BC) {
 370                cmdtype = OMAP_MMC_CMDTYPE_BC;
 371        } else if (mmc_cmd_type(cmd) == MMC_CMD_BCR) {
 372                cmdtype = OMAP_MMC_CMDTYPE_BCR;
 373        } else {
 374                cmdtype = OMAP_MMC_CMDTYPE_AC;
 375        }
 376
 377        cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
 378
 379        if (host->current_slot->bus_mode == MMC_BUSMODE_OPENDRAIN)
 380                cmdreg |= 1 << 6;
 381
 382        if (cmd->flags & MMC_RSP_BUSY)
 383                cmdreg |= 1 << 11;
 384
 385        if (host->data && !(host->data->flags & MMC_DATA_WRITE))
 386                cmdreg |= 1 << 15;
 387
 388        mod_timer(&host->cmd_abort_timer, jiffies + HZ/2);
 389
 390        OMAP_MMC_WRITE(host, CTO, 200);
 391        OMAP_MMC_WRITE(host, ARGL, cmd->arg & 0xffff);
 392        OMAP_MMC_WRITE(host, ARGH, cmd->arg >> 16);
 393        irq_mask = OMAP_MMC_STAT_A_EMPTY    | OMAP_MMC_STAT_A_FULL    |
 394                   OMAP_MMC_STAT_CMD_CRC    | OMAP_MMC_STAT_CMD_TOUT  |
 395                   OMAP_MMC_STAT_DATA_CRC   | OMAP_MMC_STAT_DATA_TOUT |
 396                   OMAP_MMC_STAT_END_OF_CMD | OMAP_MMC_STAT_CARD_ERR  |
 397                   OMAP_MMC_STAT_END_OF_DATA;
 398        if (cmd->opcode == MMC_ERASE)
 399                irq_mask &= ~OMAP_MMC_STAT_DATA_TOUT;
 400        OMAP_MMC_WRITE(host, IE, irq_mask);
 401        OMAP_MMC_WRITE(host, CMD, cmdreg);
 402}
 403
 404static void
 405mmc_omap_release_dma(struct mmc_omap_host *host, struct mmc_data *data,
 406                     int abort)
 407{
 408        enum dma_data_direction dma_data_dir;
 409        struct device *dev = mmc_dev(host->mmc);
 410        struct dma_chan *c;
 411
 412        if (data->flags & MMC_DATA_WRITE) {
 413                dma_data_dir = DMA_TO_DEVICE;
 414                c = host->dma_tx;
 415        } else {
 416                dma_data_dir = DMA_FROM_DEVICE;
 417                c = host->dma_rx;
 418        }
 419        if (c) {
 420                if (data->error) {
 421                        dmaengine_terminate_all(c);
 422                        /* Claim nothing transferred on error... */
 423                        data->bytes_xfered = 0;
 424                }
 425                dev = c->device->dev;
 426        }
 427        dma_unmap_sg(dev, data->sg, host->sg_len, dma_data_dir);
 428}
 429
 430static void mmc_omap_send_stop_work(struct work_struct *work)
 431{
 432        struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
 433                                                  send_stop_work);
 434        struct mmc_omap_slot *slot = host->current_slot;
 435        struct mmc_data *data = host->stop_data;
 436        unsigned long tick_ns;
 437
 438        tick_ns = DIV_ROUND_UP(NSEC_PER_SEC, slot->fclk_freq);
 439        ndelay(8*tick_ns);
 440
 441        mmc_omap_start_command(host, data->stop);
 442}
 443
 444static void
 445mmc_omap_xfer_done(struct mmc_omap_host *host, struct mmc_data *data)
 446{
 447        if (host->dma_in_use)
 448                mmc_omap_release_dma(host, data, data->error);
 449
 450        host->data = NULL;
 451        host->sg_len = 0;
 452
 453        /* NOTE:  MMC layer will sometimes poll-wait CMD13 next, issuing
 454         * dozens of requests until the card finishes writing data.
 455         * It'd be cheaper to just wait till an EOFB interrupt arrives...
 456         */
 457
 458        if (!data->stop) {
 459                struct mmc_host *mmc;
 460
 461                host->mrq = NULL;
 462                mmc = host->mmc;
 463                mmc_omap_release_slot(host->current_slot, 1);
 464                mmc_request_done(mmc, data->mrq);
 465                return;
 466        }
 467
 468        host->stop_data = data;
 469        queue_work(host->mmc_omap_wq, &host->send_stop_work);
 470}
 471
 472static void
 473mmc_omap_send_abort(struct mmc_omap_host *host, int maxloops)
 474{
 475        struct mmc_omap_slot *slot = host->current_slot;
 476        unsigned int restarts, passes, timeout;
 477        u16 stat = 0;
 478
 479        /* Sending abort takes 80 clocks. Have some extra and round up */
 480        timeout = DIV_ROUND_UP(120 * USEC_PER_SEC, slot->fclk_freq);
 481        restarts = 0;
 482        while (restarts < maxloops) {
 483                OMAP_MMC_WRITE(host, STAT, 0xFFFF);
 484                OMAP_MMC_WRITE(host, CMD, (3 << 12) | (1 << 7));
 485
 486                passes = 0;
 487                while (passes < timeout) {
 488                        stat = OMAP_MMC_READ(host, STAT);
 489                        if (stat & OMAP_MMC_STAT_END_OF_CMD)
 490                                goto out;
 491                        udelay(1);
 492                        passes++;
 493                }
 494
 495                restarts++;
 496        }
 497out:
 498        OMAP_MMC_WRITE(host, STAT, stat);
 499}
 500
 501static void
 502mmc_omap_abort_xfer(struct mmc_omap_host *host, struct mmc_data *data)
 503{
 504        if (host->dma_in_use)
 505                mmc_omap_release_dma(host, data, 1);
 506
 507        host->data = NULL;
 508        host->sg_len = 0;
 509
 510        mmc_omap_send_abort(host, 10000);
 511}
 512
 513static void
 514mmc_omap_end_of_data(struct mmc_omap_host *host, struct mmc_data *data)
 515{
 516        unsigned long flags;
 517        int done;
 518
 519        if (!host->dma_in_use) {
 520                mmc_omap_xfer_done(host, data);
 521                return;
 522        }
 523        done = 0;
 524        spin_lock_irqsave(&host->dma_lock, flags);
 525        if (host->dma_done)
 526                done = 1;
 527        else
 528                host->brs_received = 1;
 529        spin_unlock_irqrestore(&host->dma_lock, flags);
 530        if (done)
 531                mmc_omap_xfer_done(host, data);
 532}
 533
 534static void
 535mmc_omap_dma_done(struct mmc_omap_host *host, struct mmc_data *data)
 536{
 537        unsigned long flags;
 538        int done;
 539
 540        done = 0;
 541        spin_lock_irqsave(&host->dma_lock, flags);
 542        if (host->brs_received)
 543                done = 1;
 544        else
 545                host->dma_done = 1;
 546        spin_unlock_irqrestore(&host->dma_lock, flags);
 547        if (done)
 548                mmc_omap_xfer_done(host, data);
 549}
 550
 551static void
 552mmc_omap_cmd_done(struct mmc_omap_host *host, struct mmc_command *cmd)
 553{
 554        host->cmd = NULL;
 555
 556        del_timer(&host->cmd_abort_timer);
 557
 558        if (cmd->flags & MMC_RSP_PRESENT) {
 559                if (cmd->flags & MMC_RSP_136) {
 560                        /* response type 2 */
 561                        cmd->resp[3] =
 562                                OMAP_MMC_READ(host, RSP0) |
 563                                (OMAP_MMC_READ(host, RSP1) << 16);
 564                        cmd->resp[2] =
 565                                OMAP_MMC_READ(host, RSP2) |
 566                                (OMAP_MMC_READ(host, RSP3) << 16);
 567                        cmd->resp[1] =
 568                                OMAP_MMC_READ(host, RSP4) |
 569                                (OMAP_MMC_READ(host, RSP5) << 16);
 570                        cmd->resp[0] =
 571                                OMAP_MMC_READ(host, RSP6) |
 572                                (OMAP_MMC_READ(host, RSP7) << 16);
 573                } else {
 574                        /* response types 1, 1b, 3, 4, 5, 6 */
 575                        cmd->resp[0] =
 576                                OMAP_MMC_READ(host, RSP6) |
 577                                (OMAP_MMC_READ(host, RSP7) << 16);
 578                }
 579        }
 580
 581        if (host->data == NULL || cmd->error) {
 582                struct mmc_host *mmc;
 583
 584                if (host->data != NULL)
 585                        mmc_omap_abort_xfer(host, host->data);
 586                host->mrq = NULL;
 587                mmc = host->mmc;
 588                mmc_omap_release_slot(host->current_slot, 1);
 589                mmc_request_done(mmc, cmd->mrq);
 590        }
 591}
 592
 593/*
 594 * Abort stuck command. Can occur when card is removed while it is being
 595 * read.
 596 */
 597static void mmc_omap_abort_command(struct work_struct *work)
 598{
 599        struct mmc_omap_host *host = container_of(work, struct mmc_omap_host,
 600                                                  cmd_abort_work);
 601        BUG_ON(!host->cmd);
 602
 603        dev_dbg(mmc_dev(host->mmc), "Aborting stuck command CMD%d\n",
 604                host->cmd->opcode);
 605
 606        if (host->cmd->error == 0)
 607                host->cmd->error = -ETIMEDOUT;
 608
 609        if (host->data == NULL) {
 610                struct mmc_command *cmd;
 611                struct mmc_host    *mmc;
 612
 613                cmd = host->cmd;
 614                host->cmd = NULL;
 615                mmc_omap_send_abort(host, 10000);
 616
 617                host->mrq = NULL;
 618                mmc = host->mmc;
 619                mmc_omap_release_slot(host->current_slot, 1);
 620                mmc_request_done(mmc, cmd->mrq);
 621        } else
 622                mmc_omap_cmd_done(host, host->cmd);
 623
 624        host->abort = 0;
 625        enable_irq(host->irq);
 626}
 627
 628static void
 629mmc_omap_cmd_timer(unsigned long data)
 630{
 631        struct mmc_omap_host *host = (struct mmc_omap_host *) data;
 632        unsigned long flags;
 633
 634        spin_lock_irqsave(&host->slot_lock, flags);
 635        if (host->cmd != NULL && !host->abort) {
 636                OMAP_MMC_WRITE(host, IE, 0);
 637                disable_irq(host->irq);
 638                host->abort = 1;
 639                queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
 640        }
 641        spin_unlock_irqrestore(&host->slot_lock, flags);
 642}
 643
 644/* PIO only */
 645static void
 646mmc_omap_sg_to_buf(struct mmc_omap_host *host)
 647{
 648        struct scatterlist *sg;
 649
 650        sg = host->data->sg + host->sg_idx;
 651        host->buffer_bytes_left = sg->length;
 652        host->buffer = sg_virt(sg);
 653        if (host->buffer_bytes_left > host->total_bytes_left)
 654                host->buffer_bytes_left = host->total_bytes_left;
 655}
 656
 657static void
 658mmc_omap_clk_timer(unsigned long data)
 659{
 660        struct mmc_omap_host *host = (struct mmc_omap_host *) data;
 661
 662        mmc_omap_fclk_enable(host, 0);
 663}
 664
 665/* PIO only */
 666static void
 667mmc_omap_xfer_data(struct mmc_omap_host *host, int write)
 668{
 669        int n, nwords;
 670
 671        if (host->buffer_bytes_left == 0) {
 672                host->sg_idx++;
 673                BUG_ON(host->sg_idx == host->sg_len);
 674                mmc_omap_sg_to_buf(host);
 675        }
 676        n = 64;
 677        if (n > host->buffer_bytes_left)
 678                n = host->buffer_bytes_left;
 679
 680        /* Round up to handle odd number of bytes to transfer */
 681        nwords = DIV_ROUND_UP(n, 2);
 682
 683        host->buffer_bytes_left -= n;
 684        host->total_bytes_left -= n;
 685        host->data->bytes_xfered += n;
 686
 687        if (write) {
 688                __raw_writesw(host->virt_base + OMAP_MMC_REG(host, DATA),
 689                              host->buffer, nwords);
 690        } else {
 691                __raw_readsw(host->virt_base + OMAP_MMC_REG(host, DATA),
 692                             host->buffer, nwords);
 693        }
 694
 695        host->buffer += nwords;
 696}
 697
 698#ifdef CONFIG_MMC_DEBUG
 699static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
 700{
 701        static const char *mmc_omap_status_bits[] = {
 702                "EOC", "CD", "CB", "BRS", "EOFB", "DTO", "DCRC", "CTO",
 703                "CCRC", "CRW", "AF", "AE", "OCRB", "CIRQ", "CERR"
 704        };
 705        int i;
 706        char res[64], *buf = res;
 707
 708        buf += sprintf(buf, "MMC IRQ 0x%x:", status);
 709
 710        for (i = 0; i < ARRAY_SIZE(mmc_omap_status_bits); i++)
 711                if (status & (1 << i))
 712                        buf += sprintf(buf, " %s", mmc_omap_status_bits[i]);
 713        dev_vdbg(mmc_dev(host->mmc), "%s\n", res);
 714}
 715#else
 716static void mmc_omap_report_irq(struct mmc_omap_host *host, u16 status)
 717{
 718}
 719#endif
 720
 721
 722static irqreturn_t mmc_omap_irq(int irq, void *dev_id)
 723{
 724        struct mmc_omap_host * host = (struct mmc_omap_host *)dev_id;
 725        u16 status;
 726        int end_command;
 727        int end_transfer;
 728        int transfer_error, cmd_error;
 729
 730        if (host->cmd == NULL && host->data == NULL) {
 731                status = OMAP_MMC_READ(host, STAT);
 732                dev_info(mmc_dev(host->slots[0]->mmc),
 733                         "Spurious IRQ 0x%04x\n", status);
 734                if (status != 0) {
 735                        OMAP_MMC_WRITE(host, STAT, status);
 736                        OMAP_MMC_WRITE(host, IE, 0);
 737                }
 738                return IRQ_HANDLED;
 739        }
 740
 741        end_command = 0;
 742        end_transfer = 0;
 743        transfer_error = 0;
 744        cmd_error = 0;
 745
 746        while ((status = OMAP_MMC_READ(host, STAT)) != 0) {
 747                int cmd;
 748
 749                OMAP_MMC_WRITE(host, STAT, status);
 750                if (host->cmd != NULL)
 751                        cmd = host->cmd->opcode;
 752                else
 753                        cmd = -1;
 754                dev_dbg(mmc_dev(host->mmc), "MMC IRQ %04x (CMD %d): ",
 755                        status, cmd);
 756                mmc_omap_report_irq(host, status);
 757
 758                if (host->total_bytes_left) {
 759                        if ((status & OMAP_MMC_STAT_A_FULL) ||
 760                            (status & OMAP_MMC_STAT_END_OF_DATA))
 761                                mmc_omap_xfer_data(host, 0);
 762                        if (status & OMAP_MMC_STAT_A_EMPTY)
 763                                mmc_omap_xfer_data(host, 1);
 764                }
 765
 766                if (status & OMAP_MMC_STAT_END_OF_DATA)
 767                        end_transfer = 1;
 768
 769                if (status & OMAP_MMC_STAT_DATA_TOUT) {
 770                        dev_dbg(mmc_dev(host->mmc), "data timeout (CMD%d)\n",
 771                                cmd);
 772                        if (host->data) {
 773                                host->data->error = -ETIMEDOUT;
 774                                transfer_error = 1;
 775                        }
 776                }
 777
 778                if (status & OMAP_MMC_STAT_DATA_CRC) {
 779                        if (host->data) {
 780                                host->data->error = -EILSEQ;
 781                                dev_dbg(mmc_dev(host->mmc),
 782                                         "data CRC error, bytes left %d\n",
 783                                        host->total_bytes_left);
 784                                transfer_error = 1;
 785                        } else {
 786                                dev_dbg(mmc_dev(host->mmc), "data CRC error\n");
 787                        }
 788                }
 789
 790                if (status & OMAP_MMC_STAT_CMD_TOUT) {
 791                        /* Timeouts are routine with some commands */
 792                        if (host->cmd) {
 793                                struct mmc_omap_slot *slot =
 794                                        host->current_slot;
 795                                if (slot == NULL ||
 796                                    !mmc_omap_cover_is_open(slot))
 797                                        dev_err(mmc_dev(host->mmc),
 798                                                "command timeout (CMD%d)\n",
 799                                                cmd);
 800                                host->cmd->error = -ETIMEDOUT;
 801                                end_command = 1;
 802                                cmd_error = 1;
 803                        }
 804                }
 805
 806                if (status & OMAP_MMC_STAT_CMD_CRC) {
 807                        if (host->cmd) {
 808                                dev_err(mmc_dev(host->mmc),
 809                                        "command CRC error (CMD%d, arg 0x%08x)\n",
 810                                        cmd, host->cmd->arg);
 811                                host->cmd->error = -EILSEQ;
 812                                end_command = 1;
 813                                cmd_error = 1;
 814                        } else
 815                                dev_err(mmc_dev(host->mmc),
 816                                        "command CRC error without cmd?\n");
 817                }
 818
 819                if (status & OMAP_MMC_STAT_CARD_ERR) {
 820                        dev_dbg(mmc_dev(host->mmc),
 821                                "ignoring card status error (CMD%d)\n",
 822                                cmd);
 823                        end_command = 1;
 824                }
 825
 826                /*
 827                 * NOTE: On 1610 the END_OF_CMD may come too early when
 828                 * starting a write
 829                 */
 830                if ((status & OMAP_MMC_STAT_END_OF_CMD) &&
 831                    (!(status & OMAP_MMC_STAT_A_EMPTY))) {
 832                        end_command = 1;
 833                }
 834        }
 835
 836        if (cmd_error && host->data) {
 837                del_timer(&host->cmd_abort_timer);
 838                host->abort = 1;
 839                OMAP_MMC_WRITE(host, IE, 0);
 840                disable_irq_nosync(host->irq);
 841                queue_work(host->mmc_omap_wq, &host->cmd_abort_work);
 842                return IRQ_HANDLED;
 843        }
 844
 845        if (end_command && host->cmd)
 846                mmc_omap_cmd_done(host, host->cmd);
 847        if (host->data != NULL) {
 848                if (transfer_error)
 849                        mmc_omap_xfer_done(host, host->data);
 850                else if (end_transfer)
 851                        mmc_omap_end_of_data(host, host->data);
 852        }
 853
 854        return IRQ_HANDLED;
 855}
 856
 857void omap_mmc_notify_cover_event(struct device *dev, int num, int is_closed)
 858{
 859        int cover_open;
 860        struct mmc_omap_host *host = dev_get_drvdata(dev);
 861        struct mmc_omap_slot *slot = host->slots[num];
 862
 863        BUG_ON(num >= host->nr_slots);
 864
 865        /* Other subsystems can call in here before we're initialised. */
 866        if (host->nr_slots == 0 || !host->slots[num])
 867                return;
 868
 869        cover_open = mmc_omap_cover_is_open(slot);
 870        if (cover_open != slot->cover_open) {
 871                slot->cover_open = cover_open;
 872                sysfs_notify(&slot->mmc->class_dev.kobj, NULL, "cover_switch");
 873        }
 874
 875        tasklet_hi_schedule(&slot->cover_tasklet);
 876}
 877
 878static void mmc_omap_cover_timer(unsigned long arg)
 879{
 880        struct mmc_omap_slot *slot = (struct mmc_omap_slot *) arg;
 881        tasklet_schedule(&slot->cover_tasklet);
 882}
 883
 884static void mmc_omap_cover_handler(unsigned long param)
 885{
 886        struct mmc_omap_slot *slot = (struct mmc_omap_slot *)param;
 887        int cover_open = mmc_omap_cover_is_open(slot);
 888
 889        mmc_detect_change(slot->mmc, 0);
 890        if (!cover_open)
 891                return;
 892
 893        /*
 894         * If no card is inserted, we postpone polling until
 895         * the cover has been closed.
 896         */
 897        if (slot->mmc->card == NULL || !mmc_card_present(slot->mmc->card))
 898                return;
 899
 900        mod_timer(&slot->cover_timer,
 901                  jiffies + msecs_to_jiffies(OMAP_MMC_COVER_POLL_DELAY));
 902}
 903
 904static void mmc_omap_dma_callback(void *priv)
 905{
 906        struct mmc_omap_host *host = priv;
 907        struct mmc_data *data = host->data;
 908
 909        /* If we got to the end of DMA, assume everything went well */
 910        data->bytes_xfered += data->blocks * data->blksz;
 911
 912        mmc_omap_dma_done(host, data);
 913}
 914
 915static inline void set_cmd_timeout(struct mmc_omap_host *host, struct mmc_request *req)
 916{
 917        u16 reg;
 918
 919        reg = OMAP_MMC_READ(host, SDIO);
 920        reg &= ~(1 << 5);
 921        OMAP_MMC_WRITE(host, SDIO, reg);
 922        /* Set maximum timeout */
 923        OMAP_MMC_WRITE(host, CTO, 0xff);
 924}
 925
 926static inline void set_data_timeout(struct mmc_omap_host *host, struct mmc_request *req)
 927{
 928        unsigned int timeout, cycle_ns;
 929        u16 reg;
 930
 931        cycle_ns = 1000000000 / host->current_slot->fclk_freq;
 932        timeout = req->data->timeout_ns / cycle_ns;
 933        timeout += req->data->timeout_clks;
 934
 935        /* Check if we need to use timeout multiplier register */
 936        reg = OMAP_MMC_READ(host, SDIO);
 937        if (timeout > 0xffff) {
 938                reg |= (1 << 5);
 939                timeout /= 1024;
 940        } else
 941                reg &= ~(1 << 5);
 942        OMAP_MMC_WRITE(host, SDIO, reg);
 943        OMAP_MMC_WRITE(host, DTO, timeout);
 944}
 945
 946static void
 947mmc_omap_prepare_data(struct mmc_omap_host *host, struct mmc_request *req)
 948{
 949        struct mmc_data *data = req->data;
 950        int i, use_dma = 1, block_size;
 951        struct scatterlist *sg;
 952        unsigned sg_len;
 953
 954        host->data = data;
 955        if (data == NULL) {
 956                OMAP_MMC_WRITE(host, BLEN, 0);
 957                OMAP_MMC_WRITE(host, NBLK, 0);
 958                OMAP_MMC_WRITE(host, BUF, 0);
 959                host->dma_in_use = 0;
 960                set_cmd_timeout(host, req);
 961                return;
 962        }
 963
 964        block_size = data->blksz;
 965
 966        OMAP_MMC_WRITE(host, NBLK, data->blocks - 1);
 967        OMAP_MMC_WRITE(host, BLEN, block_size - 1);
 968        set_data_timeout(host, req);
 969
 970        /* cope with calling layer confusion; it issues "single
 971         * block" writes using multi-block scatterlists.
 972         */
 973        sg_len = (data->blocks == 1) ? 1 : data->sg_len;
 974
 975        /* Only do DMA for entire blocks */
 976        for_each_sg(data->sg, sg, sg_len, i) {
 977                if ((sg->length % block_size) != 0) {
 978                        use_dma = 0;
 979                        break;
 980                }
 981        }
 982
 983        host->sg_idx = 0;
 984        if (use_dma) {
 985                enum dma_data_direction dma_data_dir;
 986                struct dma_async_tx_descriptor *tx;
 987                struct dma_chan *c;
 988                u32 burst, *bp;
 989                u16 buf;
 990
 991                /*
 992                 * FIFO is 16x2 bytes on 15xx, and 32x2 bytes on 16xx
 993                 * and 24xx. Use 16 or 32 word frames when the
 994                 * blocksize is at least that large. Blocksize is
 995                 * usually 512 bytes; but not for some SD reads.
 996                 */
 997                burst = mmc_omap15xx() ? 32 : 64;
 998                if (burst > data->blksz)
 999                        burst = data->blksz;
1000
1001                burst >>= 1;
1002
1003                if (data->flags & MMC_DATA_WRITE) {
1004                        c = host->dma_tx;
1005                        bp = &host->dma_tx_burst;
1006                        buf = 0x0f80 | (burst - 1) << 0;
1007                        dma_data_dir = DMA_TO_DEVICE;
1008                } else {
1009                        c = host->dma_rx;
1010                        bp = &host->dma_rx_burst;
1011                        buf = 0x800f | (burst - 1) << 8;
1012                        dma_data_dir = DMA_FROM_DEVICE;
1013                }
1014
1015                if (!c)
1016                        goto use_pio;
1017
1018                /* Only reconfigure if we have a different burst size */
1019                if (*bp != burst) {
1020                        struct dma_slave_config cfg;
1021
1022                        cfg.src_addr = host->phys_base + OMAP_MMC_REG(host, DATA);
1023                        cfg.dst_addr = host->phys_base + OMAP_MMC_REG(host, DATA);
1024                        cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1025                        cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
1026                        cfg.src_maxburst = burst;
1027                        cfg.dst_maxburst = burst;
1028
1029                        if (dmaengine_slave_config(c, &cfg))
1030                                goto use_pio;
1031
1032                        *bp = burst;
1033                }
1034
1035                host->sg_len = dma_map_sg(c->device->dev, data->sg, sg_len,
1036                                          dma_data_dir);
1037                if (host->sg_len == 0)
1038                        goto use_pio;
1039
1040                tx = dmaengine_prep_slave_sg(c, data->sg, host->sg_len,
1041                        data->flags & MMC_DATA_WRITE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
1042                        DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1043                if (!tx)
1044                        goto use_pio;
1045
1046                OMAP_MMC_WRITE(host, BUF, buf);
1047
1048                tx->callback = mmc_omap_dma_callback;
1049                tx->callback_param = host;
1050                dmaengine_submit(tx);
1051                host->brs_received = 0;
1052                host->dma_done = 0;
1053                host->dma_in_use = 1;
1054                return;
1055        }
1056 use_pio:
1057
1058        /* Revert to PIO? */
1059        OMAP_MMC_WRITE(host, BUF, 0x1f1f);
1060        host->total_bytes_left = data->blocks * block_size;
1061        host->sg_len = sg_len;
1062        mmc_omap_sg_to_buf(host);
1063        host->dma_in_use = 0;
1064}
1065
1066static void mmc_omap_start_request(struct mmc_omap_host *host,
1067                                   struct mmc_request *req)
1068{
1069        BUG_ON(host->mrq != NULL);
1070
1071        host->mrq = req;
1072
1073        /* only touch fifo AFTER the controller readies it */
1074        mmc_omap_prepare_data(host, req);
1075        mmc_omap_start_command(host, req->cmd);
1076        if (host->dma_in_use) {
1077                struct dma_chan *c = host->data->flags & MMC_DATA_WRITE ?
1078                                host->dma_tx : host->dma_rx;
1079
1080                dma_async_issue_pending(c);
1081        }
1082}
1083
1084static void mmc_omap_request(struct mmc_host *mmc, struct mmc_request *req)
1085{
1086        struct mmc_omap_slot *slot = mmc_priv(mmc);
1087        struct mmc_omap_host *host = slot->host;
1088        unsigned long flags;
1089
1090        spin_lock_irqsave(&host->slot_lock, flags);
1091        if (host->mmc != NULL) {
1092                BUG_ON(slot->mrq != NULL);
1093                slot->mrq = req;
1094                spin_unlock_irqrestore(&host->slot_lock, flags);
1095                return;
1096        } else
1097                host->mmc = mmc;
1098        spin_unlock_irqrestore(&host->slot_lock, flags);
1099        mmc_omap_select_slot(slot, 1);
1100        mmc_omap_start_request(host, req);
1101}
1102
1103static void mmc_omap_set_power(struct mmc_omap_slot *slot, int power_on,
1104                                int vdd)
1105{
1106        struct mmc_omap_host *host;
1107
1108        host = slot->host;
1109
1110        if (slot->pdata->set_power != NULL)
1111                slot->pdata->set_power(mmc_dev(slot->mmc), slot->id, power_on,
1112                                        vdd);
1113        if (mmc_omap2()) {
1114                u16 w;
1115
1116                if (power_on) {
1117                        w = OMAP_MMC_READ(host, CON);
1118                        OMAP_MMC_WRITE(host, CON, w | (1 << 11));
1119                } else {
1120                        w = OMAP_MMC_READ(host, CON);
1121                        OMAP_MMC_WRITE(host, CON, w & ~(1 << 11));
1122                }
1123        }
1124}
1125
1126static int mmc_omap_calc_divisor(struct mmc_host *mmc, struct mmc_ios *ios)
1127{
1128        struct mmc_omap_slot *slot = mmc_priv(mmc);
1129        struct mmc_omap_host *host = slot->host;
1130        int func_clk_rate = clk_get_rate(host->fclk);
1131        int dsor;
1132
1133        if (ios->clock == 0)
1134                return 0;
1135
1136        dsor = func_clk_rate / ios->clock;
1137        if (dsor < 1)
1138                dsor = 1;
1139
1140        if (func_clk_rate / dsor > ios->clock)
1141                dsor++;
1142
1143        if (dsor > 250)
1144                dsor = 250;
1145
1146        slot->fclk_freq = func_clk_rate / dsor;
1147
1148        if (ios->bus_width == MMC_BUS_WIDTH_4)
1149                dsor |= 1 << 15;
1150
1151        return dsor;
1152}
1153
1154static void mmc_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1155{
1156        struct mmc_omap_slot *slot = mmc_priv(mmc);
1157        struct mmc_omap_host *host = slot->host;
1158        int i, dsor;
1159        int clk_enabled;
1160
1161        mmc_omap_select_slot(slot, 0);
1162
1163        dsor = mmc_omap_calc_divisor(mmc, ios);
1164
1165        if (ios->vdd != slot->vdd)
1166                slot->vdd = ios->vdd;
1167
1168        clk_enabled = 0;
1169        switch (ios->power_mode) {
1170        case MMC_POWER_OFF:
1171                mmc_omap_set_power(slot, 0, ios->vdd);
1172                break;
1173        case MMC_POWER_UP:
1174                /* Cannot touch dsor yet, just power up MMC */
1175                mmc_omap_set_power(slot, 1, ios->vdd);
1176                goto exit;
1177        case MMC_POWER_ON:
1178                mmc_omap_fclk_enable(host, 1);
1179                clk_enabled = 1;
1180                dsor |= 1 << 11;
1181                break;
1182        }
1183
1184        if (slot->bus_mode != ios->bus_mode) {
1185                if (slot->pdata->set_bus_mode != NULL)
1186                        slot->pdata->set_bus_mode(mmc_dev(mmc), slot->id,
1187                                                  ios->bus_mode);
1188                slot->bus_mode = ios->bus_mode;
1189        }
1190
1191        /* On insanely high arm_per frequencies something sometimes
1192         * goes somehow out of sync, and the POW bit is not being set,
1193         * which results in the while loop below getting stuck.
1194         * Writing to the CON register twice seems to do the trick. */
1195        for (i = 0; i < 2; i++)
1196                OMAP_MMC_WRITE(host, CON, dsor);
1197        slot->saved_con = dsor;
1198        if (ios->power_mode == MMC_POWER_ON) {
1199                /* worst case at 400kHz, 80 cycles makes 200 microsecs */
1200                int usecs = 250;
1201
1202                /* Send clock cycles, poll completion */
1203                OMAP_MMC_WRITE(host, IE, 0);
1204                OMAP_MMC_WRITE(host, STAT, 0xffff);
1205                OMAP_MMC_WRITE(host, CMD, 1 << 7);
1206                while (usecs > 0 && (OMAP_MMC_READ(host, STAT) & 1) == 0) {
1207                        udelay(1);
1208                        usecs--;
1209                }
1210                OMAP_MMC_WRITE(host, STAT, 1);
1211        }
1212
1213exit:
1214        mmc_omap_release_slot(slot, clk_enabled);
1215}
1216
1217static const struct mmc_host_ops mmc_omap_ops = {
1218        .request        = mmc_omap_request,
1219        .set_ios        = mmc_omap_set_ios,
1220};
1221
1222static int mmc_omap_new_slot(struct mmc_omap_host *host, int id)
1223{
1224        struct mmc_omap_slot *slot = NULL;
1225        struct mmc_host *mmc;
1226        int r;
1227
1228        mmc = mmc_alloc_host(sizeof(struct mmc_omap_slot), host->dev);
1229        if (mmc == NULL)
1230                return -ENOMEM;
1231
1232        slot = mmc_priv(mmc);
1233        slot->host = host;
1234        slot->mmc = mmc;
1235        slot->id = id;
1236        slot->pdata = &host->pdata->slots[id];
1237
1238        host->slots[id] = slot;
1239
1240        mmc->caps = 0;
1241        if (host->pdata->slots[id].wires >= 4)
1242                mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_ERASE;
1243
1244        mmc->ops = &mmc_omap_ops;
1245        mmc->f_min = 400000;
1246
1247        if (mmc_omap2())
1248                mmc->f_max = 48000000;
1249        else
1250                mmc->f_max = 24000000;
1251        if (host->pdata->max_freq)
1252                mmc->f_max = min(host->pdata->max_freq, mmc->f_max);
1253        mmc->ocr_avail = slot->pdata->ocr_mask;
1254
1255        /* Use scatterlist DMA to reduce per-transfer costs.
1256         * NOTE max_seg_size assumption that small blocks aren't
1257         * normally used (except e.g. for reading SD registers).
1258         */
1259        mmc->max_segs = 32;
1260        mmc->max_blk_size = 2048;       /* BLEN is 11 bits (+1) */
1261        mmc->max_blk_count = 2048;      /* NBLK is 11 bits (+1) */
1262        mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1263        mmc->max_seg_size = mmc->max_req_size;
1264
1265        if (slot->pdata->get_cover_state != NULL) {
1266                setup_timer(&slot->cover_timer, mmc_omap_cover_timer,
1267                            (unsigned long)slot);
1268                tasklet_init(&slot->cover_tasklet, mmc_omap_cover_handler,
1269                             (unsigned long)slot);
1270        }
1271
1272        r = mmc_add_host(mmc);
1273        if (r < 0)
1274                goto err_remove_host;
1275
1276        if (slot->pdata->name != NULL) {
1277                r = device_create_file(&mmc->class_dev,
1278                                        &dev_attr_slot_name);
1279                if (r < 0)
1280                        goto err_remove_host;
1281        }
1282
1283        if (slot->pdata->get_cover_state != NULL) {
1284                r = device_create_file(&mmc->class_dev,
1285                                        &dev_attr_cover_switch);
1286                if (r < 0)
1287                        goto err_remove_slot_name;
1288                tasklet_schedule(&slot->cover_tasklet);
1289        }
1290
1291        return 0;
1292
1293err_remove_slot_name:
1294        if (slot->pdata->name != NULL)
1295                device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1296err_remove_host:
1297        mmc_remove_host(mmc);
1298        mmc_free_host(mmc);
1299        return r;
1300}
1301
1302static void mmc_omap_remove_slot(struct mmc_omap_slot *slot)
1303{
1304        struct mmc_host *mmc = slot->mmc;
1305
1306        if (slot->pdata->name != NULL)
1307                device_remove_file(&mmc->class_dev, &dev_attr_slot_name);
1308        if (slot->pdata->get_cover_state != NULL)
1309                device_remove_file(&mmc->class_dev, &dev_attr_cover_switch);
1310
1311        tasklet_kill(&slot->cover_tasklet);
1312        del_timer_sync(&slot->cover_timer);
1313        flush_workqueue(slot->host->mmc_omap_wq);
1314
1315        mmc_remove_host(mmc);
1316        mmc_free_host(mmc);
1317}
1318
1319static int mmc_omap_probe(struct platform_device *pdev)
1320{
1321        struct omap_mmc_platform_data *pdata = pdev->dev.platform_data;
1322        struct mmc_omap_host *host = NULL;
1323        struct resource *res;
1324        dma_cap_mask_t mask;
1325        unsigned sig = 0;
1326        int i, ret = 0;
1327        int irq;
1328
1329        if (pdata == NULL) {
1330                dev_err(&pdev->dev, "platform data missing\n");
1331                return -ENXIO;
1332        }
1333        if (pdata->nr_slots == 0) {
1334                dev_err(&pdev->dev, "no slots\n");
1335                return -EPROBE_DEFER;
1336        }
1337
1338        host = devm_kzalloc(&pdev->dev, sizeof(struct mmc_omap_host),
1339                            GFP_KERNEL);
1340        if (host == NULL)
1341                return -ENOMEM;
1342
1343        irq = platform_get_irq(pdev, 0);
1344        if (irq < 0)
1345                return -ENXIO;
1346
1347        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1348        host->virt_base = devm_ioremap_resource(&pdev->dev, res);
1349        if (IS_ERR(host->virt_base))
1350                return PTR_ERR(host->virt_base);
1351
1352        INIT_WORK(&host->slot_release_work, mmc_omap_slot_release_work);
1353        INIT_WORK(&host->send_stop_work, mmc_omap_send_stop_work);
1354
1355        INIT_WORK(&host->cmd_abort_work, mmc_omap_abort_command);
1356        setup_timer(&host->cmd_abort_timer, mmc_omap_cmd_timer,
1357                    (unsigned long) host);
1358
1359        spin_lock_init(&host->clk_lock);
1360        setup_timer(&host->clk_timer, mmc_omap_clk_timer, (unsigned long) host);
1361
1362        spin_lock_init(&host->dma_lock);
1363        spin_lock_init(&host->slot_lock);
1364        init_waitqueue_head(&host->slot_wq);
1365
1366        host->pdata = pdata;
1367        host->features = host->pdata->slots[0].features;
1368        host->dev = &pdev->dev;
1369        platform_set_drvdata(pdev, host);
1370
1371        host->id = pdev->id;
1372        host->irq = irq;
1373        host->phys_base = res->start;
1374        host->iclk = clk_get(&pdev->dev, "ick");
1375        if (IS_ERR(host->iclk))
1376                return PTR_ERR(host->iclk);
1377        clk_enable(host->iclk);
1378
1379        host->fclk = clk_get(&pdev->dev, "fck");
1380        if (IS_ERR(host->fclk)) {
1381                ret = PTR_ERR(host->fclk);
1382                goto err_free_iclk;
1383        }
1384
1385        dma_cap_zero(mask);
1386        dma_cap_set(DMA_SLAVE, mask);
1387
1388        host->dma_tx_burst = -1;
1389        host->dma_rx_burst = -1;
1390
1391        res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
1392        if (res)
1393                sig = res->start;
1394        host->dma_tx = dma_request_slave_channel_compat(mask,
1395                                omap_dma_filter_fn, &sig, &pdev->dev, "tx");
1396        if (!host->dma_tx)
1397                dev_warn(host->dev, "unable to obtain TX DMA engine channel %u\n",
1398                        sig);
1399
1400        res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
1401        if (res)
1402                sig = res->start;
1403        host->dma_rx = dma_request_slave_channel_compat(mask,
1404                                omap_dma_filter_fn, &sig, &pdev->dev, "rx");
1405        if (!host->dma_rx)
1406                dev_warn(host->dev, "unable to obtain RX DMA engine channel %u\n",
1407                        sig);
1408
1409        ret = request_irq(host->irq, mmc_omap_irq, 0, DRIVER_NAME, host);
1410        if (ret)
1411                goto err_free_dma;
1412
1413        if (pdata->init != NULL) {
1414                ret = pdata->init(&pdev->dev);
1415                if (ret < 0)
1416                        goto err_free_irq;
1417        }
1418
1419        host->nr_slots = pdata->nr_slots;
1420        host->reg_shift = (mmc_omap7xx() ? 1 : 2);
1421
1422        host->mmc_omap_wq = alloc_workqueue("mmc_omap", 0, 0);
1423        if (!host->mmc_omap_wq) {
1424                ret = -ENOMEM;
1425                goto err_plat_cleanup;
1426        }
1427
1428        for (i = 0; i < pdata->nr_slots; i++) {
1429                ret = mmc_omap_new_slot(host, i);
1430                if (ret < 0) {
1431                        while (--i >= 0)
1432                                mmc_omap_remove_slot(host->slots[i]);
1433
1434                        goto err_destroy_wq;
1435                }
1436        }
1437
1438        return 0;
1439
1440err_destroy_wq:
1441        destroy_workqueue(host->mmc_omap_wq);
1442err_plat_cleanup:
1443        if (pdata->cleanup)
1444                pdata->cleanup(&pdev->dev);
1445err_free_irq:
1446        free_irq(host->irq, host);
1447err_free_dma:
1448        if (host->dma_tx)
1449                dma_release_channel(host->dma_tx);
1450        if (host->dma_rx)
1451                dma_release_channel(host->dma_rx);
1452        clk_put(host->fclk);
1453err_free_iclk:
1454        clk_disable(host->iclk);
1455        clk_put(host->iclk);
1456        return ret;
1457}
1458
1459static int mmc_omap_remove(struct platform_device *pdev)
1460{
1461        struct mmc_omap_host *host = platform_get_drvdata(pdev);
1462        int i;
1463
1464        BUG_ON(host == NULL);
1465
1466        for (i = 0; i < host->nr_slots; i++)
1467                mmc_omap_remove_slot(host->slots[i]);
1468
1469        if (host->pdata->cleanup)
1470                host->pdata->cleanup(&pdev->dev);
1471
1472        mmc_omap_fclk_enable(host, 0);
1473        free_irq(host->irq, host);
1474        clk_put(host->fclk);
1475        clk_disable(host->iclk);
1476        clk_put(host->iclk);
1477
1478        if (host->dma_tx)
1479                dma_release_channel(host->dma_tx);
1480        if (host->dma_rx)
1481                dma_release_channel(host->dma_rx);
1482
1483        destroy_workqueue(host->mmc_omap_wq);
1484
1485        return 0;
1486}
1487
1488#if IS_BUILTIN(CONFIG_OF)
1489static const struct of_device_id mmc_omap_match[] = {
1490        { .compatible = "ti,omap2420-mmc", },
1491        { },
1492};
1493MODULE_DEVICE_TABLE(of, mmc_omap_match);
1494#endif
1495
1496static struct platform_driver mmc_omap_driver = {
1497        .probe          = mmc_omap_probe,
1498        .remove         = mmc_omap_remove,
1499        .driver         = {
1500                .name   = DRIVER_NAME,
1501                .of_match_table = of_match_ptr(mmc_omap_match),
1502        },
1503};
1504
1505module_platform_driver(mmc_omap_driver);
1506MODULE_DESCRIPTION("OMAP Multimedia Card driver");
1507MODULE_LICENSE("GPL");
1508MODULE_ALIAS("platform:" DRIVER_NAME);
1509MODULE_AUTHOR("Juha Yrjölä");
1510