summaryrefslogtreecommitdiffstats
path: root/drivers/mmc/host/mxs-mmc.c
blob: 973011f9a298ba7ecf9e49d26847d25d5ad99518 (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
/*
 * Portions copyright (C) 2003 Russell King, PXA MMCI Driver
 * Portions copyright (C) 2004-2005 Pierre Ossman, W83L51xD SD/MMC driver
 *
 * Copyright 2008 Embedded Alley Solutions, Inc.
 * Copyright 2009-2011 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/highmem.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/completion.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/mmc/sdio.h>
#include <linux/gpio.h>
#include <linux/regulator/consumer.h>
#include <linux/module.h>

#include <mach/mxs.h>
#include <mach/common.h>
#include <mach/dma.h>
#include <mach/mmc.h>

#define DRIVER_NAME	"mxs-mmc"

/* card detect polling timeout */
#define MXS_MMC_DETECT_TIMEOUT			(HZ/2)

#define SSP_VERSION_LATEST	4
#define ssp_is_old()		(host->version < SSP_VERSION_LATEST)

/* SSP registers */
#define HW_SSP_CTRL0				0x000
#define  BM_SSP_CTRL0_RUN			(1 << 29)
#define  BM_SSP_CTRL0_SDIO_IRQ_CHECK		(1 << 28)
#define  BM_SSP_CTRL0_IGNORE_CRC		(1 << 26)
#define  BM_SSP_CTRL0_READ			(1 << 25)
#define  BM_SSP_CTRL0_DATA_XFER			(1 << 24)
#define  BP_SSP_CTRL0_BUS_WIDTH			(22)
#define  BM_SSP_CTRL0_BUS_WIDTH			(0x3 << 22)
#define  BM_SSP_CTRL0_WAIT_FOR_IRQ		(1 << 21)
#define  BM_SSP_CTRL0_LONG_RESP			(1 << 19)
#define  BM_SSP_CTRL0_GET_RESP			(1 << 17)
#define  BM_SSP_CTRL0_ENABLE			(1 << 16)
#define  BP_SSP_CTRL0_XFER_COUNT		(0)
#define  BM_SSP_CTRL0_XFER_COUNT		(0xffff)
#define HW_SSP_CMD0				0x010
#define  BM_SSP_CMD0_DBL_DATA_RATE_EN		(1 << 25)
#define  BM_SSP_CMD0_SLOW_CLKING_EN		(1 << 22)
#define  BM_SSP_CMD0_CONT_CLKING_EN		(1 << 21)
#define  BM_SSP_CMD0_APPEND_8CYC		(1 << 20)
#define  BP_SSP_CMD0_BLOCK_SIZE			(16)
#define  BM_SSP_CMD0_BLOCK_SIZE			(0xf << 16)
#define  BP_SSP_CMD0_BLOCK_COUNT		(8)
#define  BM_SSP_CMD0_BLOCK_COUNT		(0xff << 8)
#define  BP_SSP_CMD0_CMD			(0)
#define  BM_SSP_CMD0_CMD			(0xff)
#define HW_SSP_CMD1				0x020
#define HW_SSP_XFER_SIZE			0x030
#define HW_SSP_BLOCK_SIZE			0x040
#define  BP_SSP_BLOCK_SIZE_BLOCK_COUNT		(4)
#define  BM_SSP_BLOCK_SIZE_BLOCK_COUNT		(0xffffff << 4)
#define  BP_SSP_BLOCK_SIZE_BLOCK_SIZE		(0)
#define  BM_SSP_BLOCK_SIZE_BLOCK_SIZE		(0xf)
#define HW_SSP_TIMING				(ssp_is_old() ? 0x050 : 0x070)
#define  BP_SSP_TIMING_TIMEOUT			(16)
#define  BM_SSP_TIMING_TIMEOUT			(0xffff << 16)
#define  BP_SSP_TIMING_CLOCK_DIVIDE		(8)
#define  BM_SSP_TIMING_CLOCK_DIVIDE		(0xff << 8)
#define  BP_SSP_TIMING_CLOCK_RATE		(0)
#define  BM_SSP_TIMING_CLOCK_RATE		(0xff)
#define HW_SSP_CTRL1				(ssp_is_old() ? 0x060 : 0x080)
#define  BM_SSP_CTRL1_SDIO_IRQ			(1 << 31)
#define  BM_SSP_CTRL1_SDIO_IRQ_EN		(1 << 30)
#define  BM_SSP_CTRL1_RESP_ERR_IRQ		(1 << 29)
#define  BM_SSP_CTRL1_RESP_ERR_IRQ_EN		(1 << 28)
#define  BM_SSP_CTRL1_RESP_TIMEOUT_IRQ		(1 << 27)
#define  BM_SSP_CTRL1_RESP_TIMEOUT_IRQ_EN	(1 << 26)
#define  BM_SSP_CTRL1_DATA_TIMEOUT_IRQ		(1 << 25)
#define  BM_SSP_CTRL1_DATA_TIMEOUT_IRQ_EN	(1 << 24)
#define  BM_SSP_CTRL1_DATA_CRC_IRQ		(1 << 23)
#define  BM_SSP_CTRL1_DATA_CRC_IRQ_EN		(1 << 22)
#define  BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ		(1 << 21)
#define  BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ_EN	(1 << 20)
#define  BM_SSP_CTRL1_RECV_TIMEOUT_IRQ		(1 << 17)
#define  BM_SSP_CTRL1_RECV_TIMEOUT_IRQ_EN	(1 << 16)
#define  BM_SSP_CTRL1_FIFO_OVERRUN_IRQ		(1 << 15)
#define  BM_SSP_CTRL1_FIFO_OVERRUN_IRQ_EN	(1 << 14)
#define  BM_SSP_CTRL1_DMA_ENABLE		(1 << 13)
#define  BM_SSP_CTRL1_POLARITY			(1 << 9)
#define  BP_SSP_CTRL1_WORD_LENGTH		(4)
#define  BM_SSP_CTRL1_WORD_LENGTH		(0xf << 4)
#define  BP_SSP_CTRL1_SSP_MODE			(0)
#define  BM_SSP_CTRL1_SSP_MODE			(0xf)
#define HW_SSP_SDRESP0				(ssp_is_old() ? 0x080 : 0x0a0)
#define HW_SSP_SDRESP1				(ssp_is_old() ? 0x090 : 0x0b0)
#define HW_SSP_SDRESP2				(ssp_is_old() ? 0x0a0 : 0x0c0)
#define HW_SSP_SDRESP3				(ssp_is_old() ? 0x0b0 : 0x0d0)
#define HW_SSP_STATUS				(ssp_is_old() ? 0x0c0 : 0x100)
#define  BM_SSP_STATUS_CARD_DETECT		(1 << 28)
#define  BM_SSP_STATUS_SDIO_IRQ			(1 << 17)
#define HW_SSP_VERSION				(cpu_is_mx23() ? 0x110 : 0x130)
#define  BP_SSP_VERSION_MAJOR			(24)

#define BF_SSP(value, field)	(((value) << BP_SSP_##field) & BM_SSP_##field)

#define MXS_MMC_IRQ_BITS	(BM_SSP_CTRL1_SDIO_IRQ		| \
				 BM_SSP_CTRL1_RESP_ERR_IRQ	| \
				 BM_SSP_CTRL1_RESP_TIMEOUT_IRQ	| \
				 BM_SSP_CTRL1_DATA_TIMEOUT_IRQ	| \
				 BM_SSP_CTRL1_DATA_CRC_IRQ	| \
				 BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ	| \
				 BM_SSP_CTRL1_RECV_TIMEOUT_IRQ  | \
				 BM_SSP_CTRL1_FIFO_OVERRUN_IRQ)

#define SSP_PIO_NUM	3

struct mxs_mmc_host {
	struct mmc_host			*mmc;
	struct mmc_request		*mrq;
	struct mmc_command		*cmd;
	struct mmc_data			*data;

	void __iomem			*base;
	int				irq;
	struct resource			*res;
	struct resource			*dma_res;
	struct clk			*clk;
	unsigned int			clk_rate;

	struct dma_chan         	*dmach;
	struct mxs_dma_data		dma_data;
	unsigned int			dma_dir;
	u32				ssp_pio_words[SSP_PIO_NUM];

	unsigned int			version;
	unsigned char			bus_width;
	spinlock_t			lock;
	int				sdio_irq_en;
};

static int mxs_mmc_get_ro(struct mmc_host *mmc)
{
	struct mxs_mmc_host *host = mmc_priv(mmc);
	struct mxs_mmc_platform_data *pdata =
		mmc_dev(host->mmc)->platform_data;

	if (!pdata)
		return -EFAULT;

	if (!gpio_is_valid(pdata->wp_gpio))
		return -EINVAL;

	return gpio_get_value(pdata->wp_gpio);
}

static int mxs_mmc_get_cd(struct mmc_host *mmc)
{
	struct mxs_mmc_host *host = mmc_priv(mmc);

	return !(readl(host->base + HW_SSP_STATUS) &
		 BM_SSP_STATUS_CARD_DETECT);
}

static void mxs_mmc_reset(struct mxs_mmc_host *host)
{
	u32 ctrl0, ctrl1;

	mxs_reset_block(host->base);

	ctrl0 = BM_SSP_CTRL0_IGNORE_CRC;
	ctrl1 = BF_SSP(0x3, CTRL1_SSP_MODE) |
		BF_SSP(0x7, CTRL1_WORD_LENGTH) |
		BM_SSP_CTRL1_DMA_ENABLE |
		BM_SSP_CTRL1_POLARITY |
		BM_SSP_CTRL1_RECV_TIMEOUT_IRQ_EN |
		BM_SSP_CTRL1_DATA_CRC_IRQ_EN |
		BM_SSP_CTRL1_DATA_TIMEOUT_IRQ_EN |
		BM_SSP_CTRL1_RESP_TIMEOUT_IRQ_EN |
		BM_SSP_CTRL1_RESP_ERR_IRQ_EN;

	writel(BF_SSP(0xffff, TIMING_TIMEOUT) |
	       BF_SSP(2, TIMING_CLOCK_DIVIDE) |
	       BF_SSP(0, TIMING_CLOCK_RATE),
	       host->base + HW_SSP_TIMING);

	if (host->sdio_irq_en) {
		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
		ctrl1 |= BM_SSP_CTRL1_SDIO_IRQ_EN;
	}

	writel(ctrl0, host->base + HW_SSP_CTRL0);
	writel(ctrl1, host->base + HW_SSP_CTRL1);
}

static void mxs_mmc_start_cmd(struct mxs_mmc_host *host,
			      struct mmc_command *cmd);

static void mxs_mmc_request_done(struct mxs_mmc_host *host)
{
	struct mmc_command *cmd = host->cmd;
	struct mmc_data *data = host->data;
	struct mmc_request *mrq = host->mrq;

	if (mmc_resp_type(cmd) & MMC_RSP_PRESENT) {
		if (mmc_resp_type(cmd) & MMC_RSP_136) {
			cmd->resp[3] = readl(host->base + HW_SSP_SDRESP0);
			cmd->resp[2] = readl(host->base + HW_SSP_SDRESP1);
			cmd->resp[1] = readl(host->base + HW_SSP_SDRESP2);
			cmd->resp[0] = readl(host->base + HW_SSP_SDRESP3);
		} else {
			cmd->resp[0] = readl(host->base + HW_SSP_SDRESP0);
		}
	}

	if (data) {
		dma_unmap_sg(mmc_dev(host->mmc), data->sg,
			     data->sg_len, host->dma_dir);
		/*
		 * If there was an error on any block, we mark all
		 * data blocks as being in error.
		 */
		if (!data->error)
			data->bytes_xfered = data->blocks * data->blksz;
		else
			data->bytes_xfered = 0;

		host->data = NULL;
		if (mrq->stop) {
			mxs_mmc_start_cmd(host, mrq->stop);
			return;
		}
	}

	host->mrq = NULL;
	mmc_request_done(host->mmc, mrq);
}

static void mxs_mmc_dma_irq_callback(void *param)
{
	struct mxs_mmc_host *host = param;

	mxs_mmc_request_done(host);
}

static irqreturn_t mxs_mmc_irq_handler(int irq, void *dev_id)
{
	struct mxs_mmc_host *host = dev_id;
	struct mmc_command *cmd = host->cmd;
	struct mmc_data *data = host->data;
	u32 stat;

	spin_lock(&host->lock);

	stat = readl(host->base + HW_SSP_CTRL1);
	writel(stat & MXS_MMC_IRQ_BITS,
	       host->base + HW_SSP_CTRL1 + MXS_CLR_ADDR);

	if ((stat & BM_SSP_CTRL1_SDIO_IRQ) && (stat & BM_SSP_CTRL1_SDIO_IRQ_EN))
		mmc_signal_sdio_irq(host->mmc);

	spin_unlock(&host->lock);

	if (stat & BM_SSP_CTRL1_RESP_TIMEOUT_IRQ)
		cmd->error = -ETIMEDOUT;
	else if (stat & BM_SSP_CTRL1_RESP_ERR_IRQ)
		cmd->error = -EIO;

	if (data) {
		if (stat & (BM_SSP_CTRL1_DATA_TIMEOUT_IRQ |
			    BM_SSP_CTRL1_RECV_TIMEOUT_IRQ))
			data->error = -ETIMEDOUT;
		else if (stat & BM_SSP_CTRL1_DATA_CRC_IRQ)
			data->error = -EILSEQ;
		else if (stat & (BM_SSP_CTRL1_FIFO_UNDERRUN_IRQ |
				 BM_SSP_CTRL1_FIFO_OVERRUN_IRQ))
			data->error = -EIO;
	}

	return IRQ_HANDLED;
}

static struct dma_async_tx_descriptor *mxs_mmc_prep_dma(
	struct mxs_mmc_host *host, unsigned int append)
{
	struct dma_async_tx_descriptor *desc;
	struct mmc_data *data = host->data;
	struct scatterlist * sgl;
	unsigned int sg_len;

	if (data) {
		/* data */
		dma_map_sg(mmc_dev(host->mmc), data->sg,
			   data->sg_len, host->dma_dir);
		sgl = data->sg;
		sg_len = data->sg_len;
	} else {
		/* pio */
		sgl = (struct scatterlist *) host->ssp_pio_words;
		sg_len = SSP_PIO_NUM;
	}

	desc = host->dmach->device->device_prep_slave_sg(host->dmach,
				sgl, sg_len, host->dma_dir, append);
	if (desc) {
		desc->callback = mxs_mmc_dma_irq_callback;
		desc->callback_param = host;
	} else {
		if (data)
			dma_unmap_sg(mmc_dev(host->mmc), data->sg,
				     data->sg_len, host->dma_dir);
	}

	return desc;
}

static void mxs_mmc_bc(struct mxs_mmc_host *host)
{
	struct mmc_command *cmd = host->cmd;
	struct dma_async_tx_descriptor *desc;
	u32 ctrl0, cmd0, cmd1;

	ctrl0 = BM_SSP_CTRL0_ENABLE | BM_SSP_CTRL0_IGNORE_CRC;
	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD) | BM_SSP_CMD0_APPEND_8CYC;
	cmd1 = cmd->arg;

	if (host->sdio_irq_en) {
		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
	}

	host->ssp_pio_words[0] = ctrl0;
	host->ssp_pio_words[1] = cmd0;
	host->ssp_pio_words[2] = cmd1;
	host->dma_dir = DMA_NONE;
	desc = mxs_mmc_prep_dma(host, 0);
	if (!desc)
		goto out;

	dmaengine_submit(desc);
	return;

out:
	dev_warn(mmc_dev(host->mmc),
		 "%s: failed to prep dma\n", __func__);
}

static void mxs_mmc_ac(struct mxs_mmc_host *host)
{
	struct mmc_command *cmd = host->cmd;
	struct dma_async_tx_descriptor *desc;
	u32 ignore_crc, get_resp, long_resp;
	u32 ctrl0, cmd0, cmd1;

	ignore_crc = (mmc_resp_type(cmd) & MMC_RSP_CRC) ?
			0 : BM_SSP_CTRL0_IGNORE_CRC;
	get_resp = (mmc_resp_type(cmd) & MMC_RSP_PRESENT) ?
			BM_SSP_CTRL0_GET_RESP : 0;
	long_resp = (mmc_resp_type(cmd) & MMC_RSP_136) ?
			BM_SSP_CTRL0_LONG_RESP : 0;

	ctrl0 = BM_SSP_CTRL0_ENABLE | ignore_crc | get_resp | long_resp;
	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD);
	cmd1 = cmd->arg;

	if (host->sdio_irq_en) {
		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
	}

	host->ssp_pio_words[0] = ctrl0;
	host->ssp_pio_words[1] = cmd0;
	host->ssp_pio_words[2] = cmd1;
	host->dma_dir = DMA_NONE;
	desc = mxs_mmc_prep_dma(host, 0);
	if (!desc)
		goto out;

	dmaengine_submit(desc);
	return;

out:
	dev_warn(mmc_dev(host->mmc),
		 "%s: failed to prep dma\n", __func__);
}

static unsigned short mxs_ns_to_ssp_ticks(unsigned clock_rate, unsigned ns)
{
	const unsigned int ssp_timeout_mul = 4096;
	/*
	 * Calculate ticks in ms since ns are large numbers
	 * and might overflow
	 */
	const unsigned int clock_per_ms = clock_rate / 1000;
	const unsigned int ms = ns / 1000;
	const unsigned int ticks = ms * clock_per_ms;
	const unsigned int ssp_ticks = ticks / ssp_timeout_mul;

	WARN_ON(ssp_ticks == 0);
	return ssp_ticks;
}

static void mxs_mmc_adtc(struct mxs_mmc_host *host)
{
	struct mmc_command *cmd = host->cmd;
	struct mmc_data *data = cmd->data;
	struct dma_async_tx_descriptor *desc;
	struct scatterlist *sgl = data->sg, *sg;
	unsigned int sg_len = data->sg_len;
	int i;

	unsigned short dma_data_dir, timeout;
	unsigned int data_size = 0, log2_blksz;
	unsigned int blocks = data->blocks;

	u32 ignore_crc, get_resp, long_resp, read;
	u32 ctrl0, cmd0, cmd1, val;

	ignore_crc = (mmc_resp_type(cmd) & MMC_RSP_CRC) ?
			0 : BM_SSP_CTRL0_IGNORE_CRC;
	get_resp = (mmc_resp_type(cmd) & MMC_RSP_PRESENT) ?
			BM_SSP_CTRL0_GET_RESP : 0;
	long_resp = (mmc_resp_type(cmd) & MMC_RSP_136) ?
			BM_SSP_CTRL0_LONG_RESP : 0;

	if (data->flags & MMC_DATA_WRITE) {
		dma_data_dir = DMA_TO_DEVICE;
		read = 0;
	} else {
		dma_data_dir = DMA_FROM_DEVICE;
		read = BM_SSP_CTRL0_READ;
	}

	ctrl0 = BF_SSP(host->bus_width, CTRL0_BUS_WIDTH) |
		ignore_crc | get_resp | long_resp |
		BM_SSP_CTRL0_DATA_XFER | read |
		BM_SSP_CTRL0_WAIT_FOR_IRQ |
		BM_SSP_CTRL0_ENABLE;

	cmd0 = BF_SSP(cmd->opcode, CMD0_CMD);

	/* get logarithm to base 2 of block size for setting register */
	log2_blksz = ilog2(data->blksz);

	/*
	 * take special care of the case that data size from data->sg
	 * is not equal to blocks x blksz
	 */
	for_each_sg(sgl, sg, sg_len, i)
		data_size += sg->length;

	if (data_size != data->blocks * data->blksz)
		blocks = 1;

	/* xfer count, block size and count need to be set differently */
	if (ssp_is_old()) {
		ctrl0 |= BF_SSP(data_size, CTRL0_XFER_COUNT);
		cmd0 |= BF_SSP(log2_blksz, CMD0_BLOCK_SIZE) |
			BF_SSP(blocks - 1, CMD0_BLOCK_COUNT);
	} else {
		writel(data_size, host->base + HW_SSP_XFER_SIZE);
		writel(BF_SSP(log2_blksz, BLOCK_SIZE_BLOCK_SIZE) |
		       BF_SSP(blocks - 1, BLOCK_SIZE_BLOCK_COUNT),
		       host->base + HW_SSP_BLOCK_SIZE);
	}

	if ((cmd->opcode == MMC_STOP_TRANSMISSION) ||
	    (cmd->opcode == SD_IO_RW_EXTENDED))
		cmd0 |= BM_SSP_CMD0_APPEND_8CYC;

	cmd1 = cmd->arg;

	if (host->sdio_irq_en) {
		ctrl0 |= BM_SSP_CTRL0_SDIO_IRQ_CHECK;
		cmd0 |= BM_SSP_CMD0_CONT_CLKING_EN | BM_SSP_CMD0_SLOW_CLKING_EN;
	}

	/* set the timeout count */
	timeout = mxs_ns_to_ssp_ticks(host->clk_rate, data->timeout_ns);
	val = readl(host->base + HW_SSP_TIMING);
	val &= ~(BM_SSP_TIMING_TIMEOUT);
	val |= BF_SSP(timeout, TIMING_TIMEOUT);
	writel(val, host->base + HW_SSP_TIMING);

	/* pio */
	host->ssp_pio_words[0] = ctrl0;
	host->ssp_pio_words[1] = cmd0;
	host->ssp_pio_words[2] = cmd1;
	host->dma_dir = DMA_NONE;
	desc = mxs_mmc_prep_dma(host, 0);
	if (!desc)
		goto out;

	/* append data sg */
	WARN_ON(host->data != NULL);
	host->data = data;
	host->dma_dir = dma_data_dir;
	desc = mxs_mmc_prep_dma(host, 1);
	if (!desc)
		goto out;

	dmaengine_submit(desc);
	return;
out:
	dev_warn(mmc_dev(host->mmc),
		 "%s: failed to prep dma\n", __func__);
}

static void mxs_mmc_start_cmd(struct mxs_mmc_host *host,
			      struct mmc_command *cmd)
{
	host->cmd = cmd;

	switch (mmc_cmd_type(cmd)) {
	case MMC_CMD_BC:
		mxs_mmc_bc(host);
		break;
	case MMC_CMD_BCR:
		mxs_mmc_ac(host);
		break;
	case MMC_CMD_AC:
		mxs_mmc_ac(host);
		break;
	case MMC_CMD_ADTC:
		mxs_mmc_adtc(host);
		break;
	default:
		dev_warn(mmc_dev(host->mmc),
			 "%s: unknown MMC command\n", __func__);
		break;
	}
}

static void mxs_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
	struct mxs_mmc_host *host = mmc_priv(mmc);

	WARN_ON(host->mrq != NULL);
	host->mrq = mrq;
	mxs_mmc_start_cmd(host, mrq->cmd);
}

static void mxs_mmc_set_clk_rate(struct mxs_mmc_host *host, unsigned int rate)
{
	unsigned int ssp_clk, ssp_sck;
	u32 clock_divide, clock_rate;
	u32 val;

	ssp_clk = clk_get_rate(host->clk);

	for (clock_divide = 2; clock_divide <= 254; clock_divide += 2) {
		clock_rate = DIV_ROUND_UP(ssp_clk, rate * clock_divide);
		clock_rate = (clock_rate > 0) ? clock_rate - 1 : 0;
		if (clock_rate <= 255)
			break;
	}

	if (clock_divide > 254) {
		dev_err(mmc_dev(host->mmc),
			"%s: cannot set clock to %d\n", __func__, rate);
		return;
	}

	ssp_sck = ssp_clk / clock_divide / (1 + clock_rate);

	val = readl(host->base + HW_SSP_TIMING);
	val &= ~(BM_SSP_TIMING_CLOCK_DIVIDE | BM_SSP_TIMING_CLOCK_RATE);
	val |= BF_SSP(clock_divide, TIMING_CLOCK_DIVIDE);
	val |= BF_SSP(clock_rate, TIMING_CLOCK_RATE);
	writel(val, host->base + HW_SSP_TIMING);

	host->clk_rate = ssp_sck;

	dev_dbg(mmc_dev(host->mmc),
		"%s: clock_divide %d, clock_rate %d, ssp_clk %d, rate_actual %d, rate_requested %d\n",
		__func__, clock_divide, clock_rate, ssp_clk, ssp_sck, rate);
}

static void mxs_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
	struct mxs_mmc_host *host = mmc_priv(mmc);

	if (ios->bus_width == MMC_BUS_WIDTH_8)
		host->bus_width = 2;
	else if (ios->bus_width == MMC_BUS_WIDTH_4)
		host->bus_width = 1;
	else
		host->bus_width = 0;

	if (ios->clock)
		mxs_mmc_set_clk_rate(host, ios->clock);
}

static void mxs_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
{
	struct mxs_mmc_host *host = mmc_priv(mmc);
	unsigned long flags;

	spin_lock_irqsave(&host->lock, flags);

	host->sdio_irq_en = enable;

	if (enable) {
		writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK,
		       host->base + HW_SSP_CTRL0 + MXS_SET_ADDR);
		writel(BM_SSP_CTRL1_SDIO_IRQ_EN,
		       host->base + HW_SSP_CTRL1 + MXS_SET_ADDR);

		if (readl(host->base + HW_SSP_STATUS) & BM_SSP_STATUS_SDIO_IRQ)
			mmc_signal_sdio_irq(host->mmc);

	} else {
		writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK,
		       host->base + HW_SSP_CTRL0 + MXS_CLR_ADDR);
		writel(BM_SSP_CTRL1_SDIO_IRQ_EN,
		       host->base + HW_SSP_CTRL1 + MXS_CLR_ADDR);
	}

	spin_unlock_irqrestore(&host->lock, flags);
}

static const struct mmc_host_ops mxs_mmc_ops = {
	.request = mxs_mmc_request,
	.get_ro = mxs_mmc_get_ro,
	.get_cd = mxs_mmc_get_cd,
	.set_ios = mxs_mmc_set_ios,
	.enable_sdio_irq = mxs_mmc_enable_sdio_irq,
};

static bool mxs_mmc_dma_filter(struct dma_chan *chan, void *param)
{
	struct mxs_mmc_host *host = param;

	if (!mxs_dma_is_apbh(chan))
		return false;

	if (chan->chan_id != host->dma_res->start)
		return false;

	chan->private = &host->dma_data;

	return true;
}

static int mxs_mmc_probe(struct platform_device *pdev)
{
	struct mxs_mmc_host *host;
	struct mmc_host *mmc;
	struct resource *iores, *dmares, *r;
	struct mxs_mmc_platform_data *pdata;
	int ret = 0, irq_err, irq_dma;
	dma_cap_mask_t mask;

	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
	irq_err = platform_get_irq(pdev, 0);
	irq_dma = platform_get_irq(pdev, 1);
	if (!iores || !dmares || irq_err < 0 || irq_dma < 0)
		return -EINVAL;

	r = request_mem_region(iores->start, resource_size(iores), pdev->name);
	if (!r)
		return -EBUSY;

	mmc = mmc_alloc_host(sizeof(struct mxs_mmc_host), &pdev->dev);
	if (!mmc) {
		ret = -ENOMEM;
		goto out_release_mem;
	}

	host = mmc_priv(mmc);
	host->base = ioremap(r->start, resource_size(r));
	if (!host->base) {
		ret = -ENOMEM;
		goto out_mmc_free;
	}

	/* only major verion does matter */
	host->version = readl(host->base + HW_SSP_VERSION) >>
			BP_SSP_VERSION_MAJOR;

	host->mmc = mmc;
	host->res = r;
	host->dma_res = dmares;
	host->irq = irq_err;
	host->sdio_irq_en = 0;

	host->clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(host->clk)) {
		ret = PTR_ERR(host->clk);
		goto out_iounmap;
	}
	clk_prepare_enable(host->clk);

	mxs_mmc_reset(host);

	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);
	host->dma_data.chan_irq = irq_dma;
	host->dmach = dma_request_channel(mask, mxs_mmc_dma_filter, host);
	if (!host->dmach) {
		dev_err(mmc_dev(host->mmc),
			"%s: failed to request dma\n", __func__);
		goto out_clk_put;
	}

	/* set mmc core parameters */
	mmc->ops = &mxs_mmc_ops;
	mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
		    MMC_CAP_SDIO_IRQ | MMC_CAP_NEEDS_POLL;

	pdata =	mmc_dev(host->mmc)->platform_data;
	if (pdata) {
		if (pdata->flags & SLOTF_8_BIT_CAPABLE)
			mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
		if (pdata->flags & SLOTF_4_BIT_CAPABLE)
			mmc->caps |= MMC_CAP_4_BIT_DATA;
	}

	mmc->f_min = 400000;
	mmc->f_max = 288000000;
	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;

	mmc->max_segs = 52;
	mmc->max_blk_size = 1 << 0xf;
	mmc->max_blk_count = (ssp_is_old()) ? 0xff : 0xffffff;
	mmc->max_req_size = (ssp_is_old()) ? 0xffff : 0xffffffff;
	mmc->max_seg_size = dma_get_max_seg_size(host->dmach->device->dev);

	platform_set_drvdata(pdev, mmc);

	ret = request_irq(host->irq, mxs_mmc_irq_handler, 0, DRIVER_NAME, host);
	if (ret)
		goto out_free_dma;

	spin_lock_init(&host->lock);

	ret = mmc_add_host(mmc);
	if (ret)
		goto out_free_irq;

	dev_info(mmc_dev(host->mmc), "initialized\n");

	return 0;

out_free_irq:
	free_irq(host->irq, host);
out_free_dma:
	if (host->dmach)
		dma_release_channel(host->dmach);
out_clk_put:
	clk_disable_unprepare(host->clk);
	clk_put(host->clk);
out_iounmap:
	iounmap(host->base);
out_mmc_free:
	mmc_free_host(mmc);
out_release_mem:
	release_mem_region(iores->start, resource_size(iores));
	return ret;
}

static int mxs_mmc_remove(struct platform_device *pdev)
{
	struct mmc_host *mmc = platform_get_drvdata(pdev);
	struct mxs_mmc_host *host = mmc_priv(mmc);
	struct resource *res = host->res;

	mmc_remove_host(mmc);

	free_irq(host->irq, host);

	platform_set_drvdata(pdev, NULL);

	if (host->dmach)
		dma_release_channel(host->dmach);

	clk_disable_unprepare(host->clk);
	clk_put(host->clk);

	iounmap(host->base);

	mmc_free_host(mmc);

	release_mem_region(res->start, resource_size(res));

	return 0;
}

#ifdef CONFIG_PM
static int mxs_mmc_suspend(struct device *dev)
{
	struct mmc_host *mmc = dev_get_drvdata(dev);
	struct mxs_mmc_host *host = mmc_priv(mmc);
	int ret = 0;

	ret = mmc_suspend_host(mmc);

	clk_disable_unprepare(host->clk);

	return ret;
}

static int mxs_mmc_resume(struct device *dev)
{
	struct mmc_host *mmc = dev_get_drvdata(dev);
	struct mxs_mmc_host *host = mmc_priv(mmc);
	int ret = 0;

	clk_prepare_enable(host->clk);

	ret = mmc_resume_host(mmc);

	return ret;
}

static const struct dev_pm_ops mxs_mmc_pm_ops = {
	.suspend	= mxs_mmc_suspend,
	.resume		= mxs_mmc_resume,
};
#endif

static struct platform_driver mxs_mmc_driver = {
	.probe		= mxs_mmc_probe,
	.remove		= mxs_mmc_remove,
	.driver		= {
		.name	= DRIVER_NAME,
		.owner	= THIS_MODULE,
#ifdef CONFIG_PM
		.pm	= &mxs_mmc_pm_ops,
#endif
	},
};

static int __init mxs_mmc_init(void)
{
	return platform_driver_register(&mxs_mmc_driver);
}

static void __exit mxs_mmc_exit(void)
{
	platform_driver_unregister(&mxs_mmc_driver);
}

module_init(mxs_mmc_init);
module_exit(mxs_mmc_exit);

MODULE_DESCRIPTION("FREESCALE MXS MMC peripheral");
MODULE_AUTHOR("Freescale Semiconductor");
MODULE_LICENSE("GPL");