aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mmc/host/tmio_mmc_pio.c
blob: 5f9ad74fbf80b3a4a3556c5c5919c9ba525c610d (plain)
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
/*
 * 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/host.h>
#include <linux/mmc/tmio.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/platform_device.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_enabled = 1;
		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);
		host->sdio_irq_enabled = 0;
	}
}

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;

	/* 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;
	}

	tmio_mmc_enable_mmc_irqs(host, TMIO_MASK_CMD);

	/* 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 tmio_mmc_data *pdata = host->pdata;
	unsigned long flags;

	mutex_lock(&host->ios_lock);

	spin_lock_irqsave(&host->lock, flags);
	if (host->mrq) {
		if (IS_ERR(host->mrq)) {
			dev_dbg(&host->pdev->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(&host->pdev->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);

	/*
	 * pdata->power == false only if COLD_CD is available, otherwise only
	 * in short time intervals during probing or resuming
	 */
	if (ios->power_mode == MMC_POWER_ON && ios->clock) {
		if (!pdata->power) {
			pm_runtime_get_sync(&host->pdev->dev);
			pdata->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 (pdata->power) {
			pdata->power = false;
			pm_runtime_put(&host->pdev->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;

	pdata->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 rtpm 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
	 *  powered on during runtime for the card detection to work.
	 */
	if (!(pdata->flags & TMIO_MMC_HAS_COLD_CD
		|| mmc->caps & MMC_CAP_NEEDS_POLL
		|| mmc->caps & MMC_CAP_NONREMOVABLE))
		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);

	/* 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;

	tmio_mmc_enable_mmc_irqs(_host, irq_mask);

	*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;

	/*
	 * We don't have to manipulate pdata->power here: if there is a card in
	 * the slot, the runtime PM is active and our .runtime_resume() will not
	 * be run. If there is no card in the slot and the platform can suspend
	 * the controller, the runtime PM is suspended and pdata->power == false,
	 * so, our .runtime_resume() will not try to detect a card in the slot.
	 */
	if (host->pdata->flags & TMIO_MMC_HAS_COLD_CD
		|| host->mmc->caps & MMC_CAP_NEEDS_POLL
		|| host->mmc->caps & MMC_CAP_NONREMOVABLE)
		pm_runtime_get_sync(&pdev->dev);

	mmc_remove_host(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(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);

	host->pm_error = pm_runtime_put_sync(dev);

	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);

	/* The MMC core will perform the complete set up */
	host->pdata->power = false;

	host->pm_global = true;
	if (!host->pm_error)
		pm_runtime_get_sync(dev);

	if (host->pm_global) {
		/* Runtime PM resume callback didn't run */
		tmio_mmc_reset(host);
		tmio_mmc_enable_dma(host, true);
		host->pm_global = false;
	}

	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);
	struct tmio_mmc_data *pdata = host->pdata;

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

	if (pdata->power) {
		/* Only entered after a card-insert interrupt */
		if (!mmc->card)
			tmio_mmc_set_ios(mmc, &mmc->ios);
		mmc_detect_change(mmc, msecs_to_jiffies(100));
	}
	host->pm_global = false;

	return 0;
}
EXPORT_SYMBOL(tmio_mmc_host_runtime_resume);

MODULE_LICENSE("GPL v2");