Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
/*
 * linux/drivers/mmc/host/tmio_mmc_pio.c
 *
 * Copyright (C) 2011 Guennadi Liakhovetski
 * Copyright (C) 2007 Ian Molton
 * Copyright (C) 2004 Ian Molton
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Driver for the MMC / SD / SDIO IP found in:
 *
 * TC6393XB, TC6391XB, TC6387XB, T7L66XB, ASIC3, SH-Mobile SoCs
 *
 * This driver draws mainly on scattered spec sheets, Reverse engineering
 * of the toshiba e800  SD driver and some parts of the 2.4 ASIC3 driver (4 bit
 * support). (Further 4 bit support from a later datasheet).
 *
 * TODO:
 *   Investigate using a workqueue for PIO transfers
 *   Eliminate FIXMEs
 *   SDIO support
 *   Better Power management
 *   Handle MMC errors better
 *   double buffer support
 *
 */

#include <linux/delay.h>
#include <linux/device.h>
#include <linux/highmem.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/mfd/tmio.h>
#include <linux/mmc/cd-gpio.h>
#include <linux/mmc/host.h>
#include <linux/mmc/tmio.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/platform_device.h>
#include <linux/pm_qos.h>
#include <linux/pm_runtime.h>
#include <linux/scatterlist.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>

#include "tmio_mmc.h"

void tmio_mmc_enable_mmc_irqs(struct tmio_mmc_host *host, u32 i)
{
	host->sdcard_irq_mask &= ~(i & TMIO_MASK_IRQ);
	sd_ctrl_write32(host, CTL_IRQ_MASK, host->sdcard_irq_mask);
}

void tmio_mmc_disable_mmc_irqs(struct tmio_mmc_host *host, u32 i)
{
	host->sdcard_irq_mask |= (i & TMIO_MASK_IRQ);
	sd_ctrl_write32(host, CTL_IRQ_MASK, host->sdcard_irq_mask);
}

static void tmio_mmc_ack_mmc_irqs(struct tmio_mmc_host *host, u32 i)
{
	sd_ctrl_write32(host, CTL_STATUS, ~i);
}

static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
{
	host->sg_len = data->sg_len;
	host->sg_ptr = data->sg;
	host->sg_orig = data->sg;
	host->sg_off = 0;
}

static int tmio_mmc_next_sg(struct tmio_mmc_host *host)
{
	host->sg_ptr = sg_next(host->sg_ptr);
	host->sg_off = 0;
	return --host->sg_len;
}

#ifdef CONFIG_MMC_DEBUG

#define STATUS_TO_TEXT(a, status, i) \
	do { \
		if (status & TMIO_STAT_##a) { \
			if (i++) \
				printk(" | "); \
			printk(#a); \
		} \
	} while (0)

static void pr_debug_status(u32 status)
{
	int i = 0;
	pr_debug("status: %08x = ", status);
	STATUS_TO_TEXT(CARD_REMOVE, status, i);
	STATUS_TO_TEXT(CARD_INSERT, status, i);
	STATUS_TO_TEXT(SIGSTATE, status, i);
	STATUS_TO_TEXT(WRPROTECT, status, i);
	STATUS_TO_TEXT(CARD_REMOVE_A, status, i);
	STATUS_TO_TEXT(CARD_INSERT_A, status, i);
	STATUS_TO_TEXT(SIGSTATE_A, status, i);
	STATUS_TO_TEXT(CMD_IDX_ERR, status, i);
	STATUS_TO_TEXT(STOPBIT_ERR, status, i);
	STATUS_TO_TEXT(ILL_FUNC, status, i);
	STATUS_TO_TEXT(CMD_BUSY, status, i);
	STATUS_TO_TEXT(CMDRESPEND, status, i);
	STATUS_TO_TEXT(DATAEND, status, i);
	STATUS_TO_TEXT(CRCFAIL, status, i);
	STATUS_TO_TEXT(DATATIMEOUT, status, i);
	STATUS_TO_TEXT(CMDTIMEOUT, status, i);
	STATUS_TO_TEXT(RXOVERFLOW, status, i);
	STATUS_TO_TEXT(TXUNDERRUN, status, i);
	STATUS_TO_TEXT(RXRDY, status, i);
	STATUS_TO_TEXT(TXRQ, status, i);
	STATUS_TO_TEXT(ILL_ACCESS, status, i);
	printk("\n");
}

#else
#define pr_debug_status(s)  do { } while (0)
#endif

static void tmio_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
{
	struct tmio_mmc_host *host = mmc_priv(mmc);

	if (enable) {
		host->sdio_irq_mask = TMIO_SDIO_MASK_ALL &
					~TMIO_SDIO_STAT_IOIRQ;
		sd_ctrl_write16(host, CTL_TRANSACTION_CTL, 0x0001);
		sd_ctrl_write16(host, CTL_SDIO_IRQ_MASK, host->sdio_irq_mask);
	} else {
		host->sdio_irq_mask = TMIO_SDIO_MASK_ALL;
		sd_ctrl_write16(host, CTL_SDIO_IRQ_MASK, host->sdio_irq_mask);
		sd_ctrl_write16(host, CTL_TRANSACTION_CTL, 0x0000);
	}
}

static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
{
	u32 clk = 0, clock;

	if (new_clock) {
		for (clock = host->mmc->f_min, clk = 0x80000080;
			new_clock >= (clock<<1); clk >>= 1)
			clock <<= 1;
		clk |= 0x100;
	}

	if (host->set_clk_div)
		host->set_clk_div(host->pdev, (clk>>22) & 1);

	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & 0x1ff);
}

static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
{
	struct resource *res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);

	/* implicit BUG_ON(!res) */
	if (resource_size(res) > 0x100) {
		sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
		msleep(10);
	}

	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~0x0100 &
		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
	msleep(10);
}

static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
{
	struct resource *res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);

	sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, 0x0100 |
		sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
	msleep(10);

	/* implicit BUG_ON(!res) */
	if (resource_size(res) > 0x100) {
		sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
		msleep(10);
	}
}

static void tmio_mmc_reset(struct tmio_mmc_host *host)
{
	struct resource *res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);

	/* FIXME - should we set stop clock reg here */
	sd_ctrl_write16(host, CTL_RESET_SD, 0x0000);
	/* implicit BUG_ON(!res) */
	if (resource_size(res) > 0x100)
		sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
	msleep(10);
	sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
	if (resource_size(res) > 0x100)
		sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
	msleep(10);
}

static void tmio_mmc_reset_work(struct work_struct *work)
{
	struct tmio_mmc_host *host = container_of(work, struct tmio_mmc_host,
						  delayed_reset_work.work);
	struct mmc_request *mrq;
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);
	mrq = host->mrq;

	/*
	 * is request already finished? Since we use a non-blocking
	 * cancel_delayed_work(), it can happen, that a .set_ios() call preempts
	 * us, so, have to check for IS_ERR(host->mrq)
	 */
	if (IS_ERR_OR_NULL(mrq)
	    || time_is_after_jiffies(host->last_req_ts +
		msecs_to_jiffies(2000))) {
		spin_unlock_irqrestore(&host->lock, flags);
		return;
	}

	dev_warn(&host->pdev->dev,
		"timeout waiting for hardware interrupt (CMD%u)\n",
		mrq->cmd->opcode);

	if (host->data)
		host->data->error = -ETIMEDOUT;
	else if (host->cmd)
		host->cmd->error = -ETIMEDOUT;
	else
		mrq->cmd->error = -ETIMEDOUT;

	host->cmd = NULL;
	host->data = NULL;
	host->force_pio = false;

	spin_unlock_irqrestore(&host->lock, flags);

	tmio_mmc_reset(host);

	/* Ready for new calls */
	host->mrq = NULL;

	tmio_mmc_abort_dma(host);
	mmc_request_done(host->mmc, mrq);
}

/* called with host->lock held, interrupts disabled */
static void tmio_mmc_finish_request(struct tmio_mmc_host *host)
{
	struct mmc_request *mrq;
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);

	mrq = host->mrq;
	if (IS_ERR_OR_NULL(mrq)) {
		spin_unlock_irqrestore(&host->lock, flags);
		return;
	}

	host->cmd = NULL;
	host->data = NULL;
	host->force_pio = false;

	cancel_delayed_work(&host->delayed_reset_work);

	host->mrq = NULL;
	spin_unlock_irqrestore(&host->lock, flags);

	if (mrq->cmd->error || (mrq->data && mrq->data->error))
		tmio_mmc_abort_dma(host);

	mmc_request_done(host->mmc, mrq);
}

static void tmio_mmc_done_work(struct work_struct *work)
{
	struct tmio_mmc_host *host = container_of(work, struct tmio_mmc_host,
						  done);
	tmio_mmc_finish_request(host);
}

/* These are the bitmasks the tmio chip requires to implement the MMC response
 * types. Note that R1 and R6 are the same in this scheme. */
#define APP_CMD        0x0040
#define RESP_NONE      0x0300
#define RESP_R1        0x0400
#define RESP_R1B       0x0500
#define RESP_R2        0x0600
#define RESP_R3        0x0700
#define DATA_PRESENT   0x0800
#define TRANSFER_READ  0x1000
#define TRANSFER_MULTI 0x2000
#define SECURITY_CMD   0x4000

static int tmio_mmc_start_command(struct tmio_mmc_host *host, struct mmc_command *cmd)
{
	struct mmc_data *data = host->data;
	int c = cmd->opcode;
	u32 irq_mask = TMIO_MASK_CMD;

	/* Command 12 is handled by hardware */
	if (cmd->opcode == 12 && !cmd->arg) {
		sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x001);
		return 0;
	}

	switch (mmc_resp_type(cmd)) {
	case MMC_RSP_NONE: c |= RESP_NONE; break;
	case MMC_RSP_R1:   c |= RESP_R1;   break;
	case MMC_RSP_R1B:  c |= RESP_R1B;  break;
	case MMC_RSP_R2:   c |= RESP_R2;   break;
	case MMC_RSP_R3:   c |= RESP_R3;   break;
	default:
		pr_debug("Unknown response type %d\n", mmc_resp_type(cmd));
		return -EINVAL;
	}

	host->cmd = cmd;

/* FIXME - this seems to be ok commented out but the spec suggest this bit
 *         should be set when issuing app commands.
 *	if(cmd->flags & MMC_FLAG_ACMD)
 *		c |= APP_CMD;
 */
	if (data) {
		c |= DATA_PRESENT;
		if (data->blocks > 1) {
			sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x100);
			c |= TRANSFER_MULTI;
		}
		if (data->flags & MMC_DATA_READ)
			c |= TRANSFER_READ;
	}

	if (!host->native_hotplug)
		irq_mask &= ~(TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT);
	tmio_mmc_enable_mmc_irqs(host, irq_mask);

	/* Fire off the command */
	sd_ctrl_write32(host, CTL_ARG_REG, cmd->arg);
	sd_ctrl_write16(host, CTL_SD_CMD, c);

	return 0;
}

/*
 * This chip always returns (at least?) as much data as you ask for.
 * I'm unsure what happens if you ask for less than a block. This should be
 * looked into to ensure that a funny length read doesn't hose the controller.
 */
static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
{
	struct mmc_data *data = host->data;
	void *sg_virt;
	unsigned short *buf;
	unsigned int count;
	unsigned long flags;

	if ((host->chan_tx || host->chan_rx) && !host->force_pio) {
		pr_err("PIO IRQ in DMA mode!\n");
		return;
	} else if (!data) {
		pr_debug("Spurious PIO IRQ\n");
		return;
	}

	sg_virt = tmio_mmc_kmap_atomic(host->sg_ptr, &flags);
	buf = (unsigned short *)(sg_virt + host->sg_off);

	count = host->sg_ptr->length - host->sg_off;
	if (count > data->blksz)
		count = data->blksz;

	pr_debug("count: %08x offset: %08x flags %08x\n",
		 count, host->sg_off, data->flags);

	/* Transfer the data */
	if (data->flags & MMC_DATA_READ)
		sd_ctrl_read16_rep(host, CTL_SD_DATA_PORT, buf, count >> 1);
	else
		sd_ctrl_write16_rep(host, CTL_SD_DATA_PORT, buf, count >> 1);

	host->sg_off += count;

	tmio_mmc_kunmap_atomic(host->sg_ptr, &flags, sg_virt);

	if (host->sg_off == host->sg_ptr->length)
		tmio_mmc_next_sg(host);

	return;
}

static void tmio_mmc_check_bounce_buffer(struct tmio_mmc_host *host)
{
	if (host->sg_ptr == &host->bounce_sg) {
		unsigned long flags;
		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
		memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
		tmio_mmc_kunmap_atomic(host->sg_orig, &flags, sg_vaddr);
	}
}

/* needs to be called with host->lock held */
void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
{
	struct mmc_data *data = host->data;
	struct mmc_command *stop;

	host->data = NULL;

	if (!data) {
		dev_warn(&host->pdev->dev, "Spurious data end IRQ\n");
		return;
	}
	stop = data->stop;

	/* FIXME - return correct transfer count on errors */
	if (!data->error)
		data->bytes_xfered = data->blocks * data->blksz;
	else
		data->bytes_xfered = 0;

	pr_debug("Completed data request\n");

	/*
	 * FIXME: other drivers allow an optional stop command of any given type
	 *        which we dont do, as the chip can auto generate them.
	 *        Perhaps we can be smarter about when to use auto CMD12 and
	 *        only issue the auto request when we know this is the desired
	 *        stop command, allowing fallback to the stop command the
	 *        upper layers expect. For now, we do what works.
	 */

	if (data->flags & MMC_DATA_READ) {
		if (host->chan_rx && !host->force_pio)
			tmio_mmc_check_bounce_buffer(host);
		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
			host->mrq);
	} else {
		dev_dbg(&host->pdev->dev, "Complete Tx request %p\n",
			host->mrq);
	}

	if (stop) {
		if (stop->opcode == 12 && !stop->arg)
			sd_ctrl_write16(host, CTL_STOP_INTERNAL_ACTION, 0x000);
		else
			BUG();
	}

	schedule_work(&host->done);
}

static void tmio_mmc_data_irq(struct tmio_mmc_host *host)
{
	struct mmc_data *data;
	spin_lock(&host->lock);
	data = host->data;

	if (!data)
		goto out;

	if (host->chan_tx && (data->flags & MMC_DATA_WRITE) && !host->force_pio) {
		/*
		 * Has all data been written out yet? Testing on SuperH showed,
		 * that in most cases the first interrupt comes already with the
		 * BUSY status bit clear, but on some operations, like mount or
		 * in the beginning of a write / sync / umount, there is one
		 * DATAEND interrupt with the BUSY bit set, in this cases
		 * waiting for one more interrupt fixes the problem.
		 */
		if (!(sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_CMD_BUSY)) {
			tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_DATAEND);
			tasklet_schedule(&host->dma_complete);
		}
	} else if (host->chan_rx && (data->flags & MMC_DATA_READ) && !host->force_pio) {
		tmio_mmc_disable_mmc_irqs(host, TMIO_STAT_DATAEND);
		tasklet_schedule(&host->dma_complete);
	} else {
		tmio_mmc_do_data_irq(host);
		tmio_mmc_disable_mmc_irqs(host, TMIO_MASK_READOP | TMIO_MASK_WRITEOP);
	}
out:
	spin_unlock(&host->lock);
}

static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
	unsigned int stat)
{
	struct mmc_command *cmd = host->cmd;
	int i, addr;

	spin_lock(&host->lock);

	if (!host->cmd) {
		pr_debug("Spurious CMD irq\n");
		goto out;
	}

	host->cmd = NULL;

	/* This controller is sicker than the PXA one. Not only do we need to
	 * drop the top 8 bits of the first response word, we also need to
	 * modify the order of the response for short response command types.
	 */

	for (i = 3, addr = CTL_RESPONSE ; i >= 0 ; i--, addr += 4)
		cmd->resp[i] = sd_ctrl_read32(host, addr);

	if (cmd->flags &  MMC_RSP_136) {
		cmd->resp[0] = (cmd->resp[0] << 8) | (cmd->resp[1] >> 24);
		cmd->resp[1] = (cmd->resp[1] << 8) | (cmd->resp[2] >> 24);
		cmd->resp[2] = (cmd->resp[2] << 8) | (cmd->resp[3] >> 24);
		cmd->resp[3] <<= 8;
	} else if (cmd->flags & MMC_RSP_R3) {
		cmd->resp[0] = cmd->resp[3];
	}

	if (stat & TMIO_STAT_CMDTIMEOUT)
		cmd->error = -ETIMEDOUT;
	else if (stat & TMIO_STAT_CRCFAIL && cmd->flags & MMC_RSP_CRC)
		cmd->error = -EILSEQ;

	/* If there is data to handle we enable data IRQs here, and
	 * we will ultimatley finish the request in the data_end handler.
	 * If theres no data or we encountered an error, finish now.
	 */
	if (host->data && !cmd->error) {
		if (host->data->flags & MMC_DATA_READ) {
			if (host->force_pio || !host->chan_rx)
				tmio_mmc_enable_mmc_irqs(host, TMIO_MASK_READOP);
			else
				tasklet_schedule(&host->dma_issue);
		} else {
			if (host->force_pio || !host->chan_tx)
				tmio_mmc_enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
			else
				tasklet_schedule(&host->dma_issue);
		}
	} else {
		schedule_work(&host->done);
	}

out:
	spin_unlock(&host->lock);
}

static void tmio_mmc_card_irq_status(struct tmio_mmc_host *host,
				       int *ireg, int *status)
{
	*status = sd_ctrl_read32(host, CTL_STATUS);
	*ireg = *status & TMIO_MASK_IRQ & ~host->sdcard_irq_mask;

	pr_debug_status(*status);
	pr_debug_status(*ireg);
}

static bool __tmio_mmc_card_detect_irq(struct tmio_mmc_host *host,
				      int ireg, int status)
{
	struct mmc_host *mmc = host->mmc;

	/* Card insert / remove attempts */
	if (ireg & (TMIO_STAT_CARD_INSERT | TMIO_STAT_CARD_REMOVE)) {
		tmio_mmc_ack_mmc_irqs(host, TMIO_STAT_CARD_INSERT |
			TMIO_STAT_CARD_REMOVE);
		if ((((ireg & TMIO_STAT_CARD_REMOVE) && mmc->card) ||
		     ((ireg & TMIO_STAT_CARD_INSERT) && !mmc->card)) &&
		    !work_pending(&mmc->detect.work))
			mmc_detect_change(host->mmc, msecs_to_jiffies(100));
		return true;
	}

	return false;
}

irqreturn_t tmio_mmc_card_detect_irq(int irq, void *devid)
{
	unsigned int ireg, status;
	struct tmio_mmc_host *host = devid;

	tmio_mmc_card_irq_status(host, &ireg, &status);
	__tmio_mmc_card_detect_irq(host, ireg, status);

	return IRQ_HANDLED;
}
EXPORT_SYMBOL(tmio_mmc_card_detect_irq);

static bool __tmio_mmc_sdcard_irq(struct tmio_mmc_host *host,
				 int ireg, int status)
{
	/* Command completion */
	if (ireg & (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT)) {
		tmio_mmc_ack_mmc_irqs(host,
			     TMIO_STAT_CMDRESPEND |
			     TMIO_STAT_CMDTIMEOUT);
		tmio_mmc_cmd_irq(host, status);
		return true;
	}

	/* Data transfer */
	if (ireg & (TMIO_STAT_RXRDY | TMIO_STAT_TXRQ)) {
		tmio_mmc_ack_mmc_irqs(host, TMIO_STAT_RXRDY | TMIO_STAT_TXRQ);
		tmio_mmc_pio_irq(host);
		return true;
	}

	/* Data transfer completion */
	if (ireg & TMIO_STAT_DATAEND) {
		tmio_mmc_ack_mmc_irqs(host, TMIO_STAT_DATAEND);
		tmio_mmc_data_irq(host);
		return true;
	}

	return false;
}

irqreturn_t tmio_mmc_sdcard_irq(int irq, void *devid)
{
	unsigned int ireg, status;
	struct tmio_mmc_host *host = devid;

	tmio_mmc_card_irq_status(host, &ireg, &status);
	__tmio_mmc_sdcard_irq(host, ireg, status);

	return IRQ_HANDLED;
}
EXPORT_SYMBOL(tmio_mmc_sdcard_irq);

irqreturn_t tmio_mmc_sdio_irq(int irq, void *devid)
{
	struct tmio_mmc_host *host = devid;
	struct mmc_host *mmc = host->mmc;
	struct tmio_mmc_data *pdata = host->pdata;
	unsigned int ireg, status;

	if (!(pdata->flags & TMIO_MMC_SDIO_IRQ))
		return IRQ_HANDLED;

	status = sd_ctrl_read16(host, CTL_SDIO_STATUS);
	ireg = status & TMIO_SDIO_MASK_ALL & ~host->sdcard_irq_mask;

	sd_ctrl_write16(host, CTL_SDIO_STATUS, status & ~TMIO_SDIO_MASK_ALL);

	if (mmc->caps & MMC_CAP_SDIO_IRQ && ireg & TMIO_SDIO_STAT_IOIRQ)
		mmc_signal_sdio_irq(mmc);

	return IRQ_HANDLED;
}
EXPORT_SYMBOL(tmio_mmc_sdio_irq);

irqreturn_t tmio_mmc_irq(int irq, void *devid)
{
	struct tmio_mmc_host *host = devid;
	unsigned int ireg, status;

	pr_debug("MMC IRQ begin\n");

	tmio_mmc_card_irq_status(host, &ireg, &status);
	if (__tmio_mmc_card_detect_irq(host, ireg, status))
		return IRQ_HANDLED;
	if (__tmio_mmc_sdcard_irq(host, ireg, status))
		return IRQ_HANDLED;

	tmio_mmc_sdio_irq(irq, devid);

	return IRQ_HANDLED;
}
EXPORT_SYMBOL(tmio_mmc_irq);

static int tmio_mmc_start_data(struct tmio_mmc_host *host,
	struct mmc_data *data)
{
	struct tmio_mmc_data *pdata = host->pdata;

	pr_debug("setup data transfer: blocksize %08x  nr_blocks %d\n",
		 data->blksz, data->blocks);

	/* Some hardware cannot perform 2 byte requests in 4 bit mode */
	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_4) {
		int blksz_2bytes = pdata->flags & TMIO_MMC_BLKSZ_2BYTES;

		if (data->blksz < 2 || (data->blksz < 4 && !blksz_2bytes)) {
			pr_err("%s: %d byte block unsupported in 4 bit mode\n",
			       mmc_hostname(host->mmc), data->blksz);
			return -EINVAL;
		}
	}

	tmio_mmc_init_sg(host, data);
	host->data = data;

	/* Set transfer length / blocksize */
	sd_ctrl_write16(host, CTL_SD_XFER_LEN, data->blksz);
	sd_ctrl_write16(host, CTL_XFER_BLK_COUNT, data->blocks);

	tmio_mmc_start_dma(host, data);

	return 0;
}

/* Process requests from the MMC layer */
static void tmio_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
	struct tmio_mmc_host *host = mmc_priv(mmc);
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&host->lock, flags);

	if (host->mrq) {
		pr_debug("request not null\n");
		if (IS_ERR(host->mrq)) {
			spin_unlock_irqrestore(&host->lock, flags);
			mrq->cmd->error = -EAGAIN;
			mmc_request_done(mmc, mrq);
			return;
		}
	}

	host->last_req_ts = jiffies;
	wmb();
	host->mrq = mrq;

	spin_unlock_irqrestore(&host->lock, flags);

	if (mrq->data) {
		ret = tmio_mmc_start_data(host, mrq->data);
		if (ret)
			goto fail;
	}

	ret = tmio_mmc_start_command(host, mrq->cmd);
	if (!ret) {
		schedule_delayed_work(&host->delayed_reset_work,
				      msecs_to_jiffies(2000));
		return;
	}

fail:
	host->force_pio = false;
	host->mrq = NULL;
	mrq->cmd->error = ret;
	mmc_request_done(mmc, mrq);
}

/* Set MMC clock / power.
 * Note: This controller uses a simple divider scheme therefore it cannot
 * run a MMC card at full speed (20MHz). The max clock is 24MHz on SD, but as
 * MMC wont run that fast, it has to be clocked at 12MHz which is the next
 * slowest setting.
 */
static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
	struct tmio_mmc_host *host = mmc_priv(mmc);
	struct device *dev = &host->pdev->dev;
	unsigned long flags;

	mutex_lock(&host->ios_lock);

	spin_lock_irqsave(&host->lock, flags);
	if (host->mrq) {
		if (IS_ERR(host->mrq)) {
			dev_dbg(dev,
				"%s.%d: concurrent .set_ios(), clk %u, mode %u\n",
				current->comm, task_pid_nr(current),
				ios->clock, ios->power_mode);
			host->mrq = ERR_PTR(-EINTR);
		} else {
			dev_dbg(dev,
				"%s.%d: CMD%u active since %lu, now %lu!\n",
				current->comm, task_pid_nr(current),
				host->mrq->cmd->opcode, host->last_req_ts, jiffies);
		}
		spin_unlock_irqrestore(&host->lock, flags);

		mutex_unlock(&host->ios_lock);
		return;
	}

	host->mrq = ERR_PTR(-EBUSY);

	spin_unlock_irqrestore(&host->lock, flags);

	/*
	 * host->power toggles between false and true in both cases - either
	 * or not the controller can be runtime-suspended during inactivity.
	 * But if the controller has to be kept on, the runtime-pm usage_count
	 * is kept positive, so no suspending actually takes place.
	 */
	if (ios->power_mode == MMC_POWER_ON && ios->clock) {
		if (!host->power) {
			pm_runtime_get_sync(dev);
			host->power = true;
		}
		tmio_mmc_set_clock(host, ios->clock);
		/* power up SD bus */
		if (host->set_pwr)
			host->set_pwr(host->pdev, 1);
		/* start bus clock */
		tmio_mmc_clk_start(host);
	} else if (ios->power_mode != MMC_POWER_UP) {
		if (host->set_pwr && ios->power_mode == MMC_POWER_OFF)
			host->set_pwr(host->pdev, 0);
		if (host->power) {
			host->power = false;
			pm_runtime_put(dev);
		}
		tmio_mmc_clk_stop(host);
	}

	switch (ios->bus_width) {
	case MMC_BUS_WIDTH_1:
		sd_ctrl_write16(host, CTL_SD_MEM_CARD_OPT, 0x80e0);
	break;
	case MMC_BUS_WIDTH_4:
		sd_ctrl_write16(host, CTL_SD_MEM_CARD_OPT, 0x00e0);
	break;
	}

	/* Let things settle. delay taken from winCE driver */
	udelay(140);
	if (PTR_ERR(host->mrq) == -EINTR)
		dev_dbg(&host->pdev->dev,
			"%s.%d: IOS interrupted: clk %u, mode %u",
			current->comm, task_pid_nr(current),
			ios->clock, ios->power_mode);
	host->mrq = NULL;

	mutex_unlock(&host->ios_lock);
}

static int tmio_mmc_get_ro(struct mmc_host *mmc)
{
	struct tmio_mmc_host *host = mmc_priv(mmc);
	struct tmio_mmc_data *pdata = host->pdata;

	return !((pdata->flags & TMIO_MMC_WRPROTECT_DISABLE) ||
		 (sd_ctrl_read32(host, CTL_STATUS) & TMIO_STAT_WRPROTECT));
}

static int tmio_mmc_get_cd(struct mmc_host *mmc)
{
	struct tmio_mmc_host *host = mmc_priv(mmc);
	struct tmio_mmc_data *pdata = host->pdata;

	if (!pdata->get_cd)
		return -ENOSYS;
	else
		return pdata->get_cd(host->pdev);
}

static const struct mmc_host_ops tmio_mmc_ops = {
	.request	= tmio_mmc_request,
	.set_ios	= tmio_mmc_set_ios,
	.get_ro         = tmio_mmc_get_ro,
	.get_cd		= tmio_mmc_get_cd,
	.enable_sdio_irq = tmio_mmc_enable_sdio_irq,
};

int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
				  struct platform_device *pdev,
				  struct tmio_mmc_data *pdata)
{
	struct tmio_mmc_host *_host;
	struct mmc_host *mmc;
	struct resource *res_ctl;
	int ret;
	u32 irq_mask = TMIO_MASK_CMD;

	res_ctl = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res_ctl)
		return -EINVAL;

	mmc = mmc_alloc_host(sizeof(struct tmio_mmc_host), &pdev->dev);
	if (!mmc)
		return -ENOMEM;

	pdata->dev = &pdev->dev;
	_host = mmc_priv(mmc);
	_host->pdata = pdata;
	_host->mmc = mmc;
	_host->pdev = pdev;
	platform_set_drvdata(pdev, mmc);

	_host->set_pwr = pdata->set_pwr;
	_host->set_clk_div = pdata->set_clk_div;

	/* SD control register space size is 0x200, 0x400 for bus_shift=1 */
	_host->bus_shift = resource_size(res_ctl) >> 10;

	_host->ctl = ioremap(res_ctl->start, resource_size(res_ctl));
	if (!_host->ctl) {
		ret = -ENOMEM;
		goto host_free;
	}

	mmc->ops = &tmio_mmc_ops;
	mmc->caps = MMC_CAP_4_BIT_DATA | pdata->capabilities;
	mmc->f_max = pdata->hclk;
	mmc->f_min = mmc->f_max / 512;
	mmc->max_segs = 32;
	mmc->max_blk_size = 512;
	mmc->max_blk_count = (PAGE_CACHE_SIZE / mmc->max_blk_size) *
		mmc->max_segs;
	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
	mmc->max_seg_size = mmc->max_req_size;
	if (pdata->ocr_mask)
		mmc->ocr_avail = pdata->ocr_mask;
	else
		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;

	_host->native_hotplug = !(pdata->flags & TMIO_MMC_USE_GPIO_CD ||
				  mmc->caps & MMC_CAP_NEEDS_POLL ||
				  mmc->caps & MMC_CAP_NONREMOVABLE);

	_host->power = false;
	pm_runtime_enable(&pdev->dev);
	ret = pm_runtime_resume(&pdev->dev);
	if (ret < 0)
		goto pm_disable;

	/*
	 * There are 4 different scenarios for the card detection:
	 *  1) an external gpio irq handles the cd (best for power savings)
	 *  2) internal sdhi irq handles the cd
	 *  3) a worker thread polls the sdhi - indicated by MMC_CAP_NEEDS_POLL
	 *  4) the medium is non-removable - indicated by MMC_CAP_NONREMOVABLE
	 *
	 *  While we increment the runtime PM counter for all scenarios when
	 *  the mmc core activates us by calling an appropriate set_ios(), we
	 *  must additionally ensure that in case 2) the tmio mmc hardware stays
	 *  additionally ensure that in case 2) the tmio mmc hardware stays
	 *  powered on during runtime for the card detection to work.
	 */
	if (_host->native_hotplug)
		pm_runtime_get_noresume(&pdev->dev);

	tmio_mmc_clk_stop(_host);
	tmio_mmc_reset(_host);

	_host->sdcard_irq_mask = sd_ctrl_read32(_host, CTL_IRQ_MASK);
	tmio_mmc_disable_mmc_irqs(_host, TMIO_MASK_ALL);
	if (pdata->flags & TMIO_MMC_SDIO_IRQ)
		tmio_mmc_enable_sdio_irq(mmc, 0);

	spin_lock_init(&_host->lock);
	mutex_init(&_host->ios_lock);

	/* Init delayed work for request timeouts */
	INIT_DELAYED_WORK(&_host->delayed_reset_work, tmio_mmc_reset_work);
	INIT_WORK(&_host->done, tmio_mmc_done_work);

	/* See if we also get DMA */
	tmio_mmc_request_dma(_host, pdata);

	mmc_add_host(mmc);

	dev_pm_qos_expose_latency_limit(&pdev->dev, 100);

	/* Unmask the IRQs we want to know about */
	if (!_host->chan_rx)
		irq_mask |= TMIO_MASK_READOP;
	if (!_host->chan_tx)
		irq_mask |= TMIO_MASK_WRITEOP;
	if (!_host->native_hotplug)
		irq_mask &= ~(TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT);

	tmio_mmc_enable_mmc_irqs(_host, irq_mask);

	if (pdata->flags & TMIO_MMC_USE_GPIO_CD) {
		ret = mmc_cd_gpio_request(mmc, pdata->cd_gpio);
		if (ret < 0) {
			tmio_mmc_host_remove(_host);
			return ret;
		}
	}

	*host = _host;

	return 0;

pm_disable:
	pm_runtime_disable(&pdev->dev);
	iounmap(_host->ctl);
host_free:
	mmc_free_host(mmc);

	return ret;
}
EXPORT_SYMBOL(tmio_mmc_host_probe);

void tmio_mmc_host_remove(struct tmio_mmc_host *host)
{
	struct platform_device *pdev = host->pdev;
	struct tmio_mmc_data *pdata = host->pdata;
	struct mmc_host *mmc = host->mmc;

	if (pdata->flags & TMIO_MMC_USE_GPIO_CD)
		/*
		 * This means we can miss a card-eject, but this is anyway
		 * possible, because of delayed processing of hotplug events.
		 */
		mmc_cd_gpio_free(mmc);

	if (!host->native_hotplug)
		pm_runtime_get_sync(&pdev->dev);

	dev_pm_qos_hide_latency_limit(&pdev->dev);

	mmc_remove_host(mmc);
	cancel_work_sync(&host->done);
	cancel_delayed_work_sync(&host->delayed_reset_work);
	tmio_mmc_release_dma(host);

	pm_runtime_put_sync(&pdev->dev);
	pm_runtime_disable(&pdev->dev);

	iounmap(host->ctl);
	mmc_free_host(mmc);
}
EXPORT_SYMBOL(tmio_mmc_host_remove);

#ifdef CONFIG_PM
int tmio_mmc_host_suspend(struct device *dev)
{
	struct mmc_host *mmc = dev_get_drvdata(dev);
	struct tmio_mmc_host *host = mmc_priv(mmc);
	int ret = mmc_suspend_host(mmc);

	if (!ret)
		tmio_mmc_disable_mmc_irqs(host, TMIO_MASK_ALL);

	return ret;
}
EXPORT_SYMBOL(tmio_mmc_host_suspend);

int tmio_mmc_host_resume(struct device *dev)
{
	struct mmc_host *mmc = dev_get_drvdata(dev);
	struct tmio_mmc_host *host = mmc_priv(mmc);

	tmio_mmc_reset(host);
	tmio_mmc_enable_dma(host, true);

	/* The MMC core will perform the complete set up */
	return mmc_resume_host(mmc);
}
EXPORT_SYMBOL(tmio_mmc_host_resume);

#endif	/* CONFIG_PM */

int tmio_mmc_host_runtime_suspend(struct device *dev)
{
	return 0;
}
EXPORT_SYMBOL(tmio_mmc_host_runtime_suspend);

int tmio_mmc_host_runtime_resume(struct device *dev)
{
	struct mmc_host *mmc = dev_get_drvdata(dev);
	struct tmio_mmc_host *host = mmc_priv(mmc);

	tmio_mmc_reset(host);
	tmio_mmc_enable_dma(host, true);

	return 0;
}
EXPORT_SYMBOL(tmio_mmc_host_runtime_resume);

MODULE_LICENSE("GPL v2");