aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-mt65xx.c
blob: 5d643051bf3de99936bed13783e573cfd910d6a2 (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2015 MediaTek Inc.
 * Author: Leilk Liu <leilk.liu@mediatek.com>
 */

#include <linux/clk.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/platform_data/spi-mt65xx.h>
#include <linux/pm_runtime.h>
#include <linux/spi/spi.h>
#include <linux/dma-mapping.h>

#define SPI_CFG0_REG                      0x0000
#define SPI_CFG1_REG                      0x0004
#define SPI_TX_SRC_REG                    0x0008
#define SPI_RX_DST_REG                    0x000c
#define SPI_TX_DATA_REG                   0x0010
#define SPI_RX_DATA_REG                   0x0014
#define SPI_CMD_REG                       0x0018
#define SPI_STATUS0_REG                   0x001c
#define SPI_PAD_SEL_REG                   0x0024
#define SPI_CFG2_REG                      0x0028
#define SPI_TX_SRC_REG_64                 0x002c
#define SPI_RX_DST_REG_64                 0x0030

#define SPI_CFG0_SCK_HIGH_OFFSET          0
#define SPI_CFG0_SCK_LOW_OFFSET           8
#define SPI_CFG0_CS_HOLD_OFFSET           16
#define SPI_CFG0_CS_SETUP_OFFSET          24
#define SPI_ADJUST_CFG0_CS_HOLD_OFFSET    0
#define SPI_ADJUST_CFG0_CS_SETUP_OFFSET   16

#define SPI_CFG1_CS_IDLE_OFFSET           0
#define SPI_CFG1_PACKET_LOOP_OFFSET       8
#define SPI_CFG1_PACKET_LENGTH_OFFSET     16
#define SPI_CFG1_GET_TICK_DLY_OFFSET      30

#define SPI_CFG1_CS_IDLE_MASK             0xff
#define SPI_CFG1_PACKET_LOOP_MASK         0xff00
#define SPI_CFG1_PACKET_LENGTH_MASK       0x3ff0000
#define SPI_CFG2_SCK_HIGH_OFFSET          0
#define SPI_CFG2_SCK_LOW_OFFSET           16

#define SPI_CMD_ACT                  BIT(0)
#define SPI_CMD_RESUME               BIT(1)
#define SPI_CMD_RST                  BIT(2)
#define SPI_CMD_PAUSE_EN             BIT(4)
#define SPI_CMD_DEASSERT             BIT(5)
#define SPI_CMD_SAMPLE_SEL           BIT(6)
#define SPI_CMD_CS_POL               BIT(7)
#define SPI_CMD_CPHA                 BIT(8)
#define SPI_CMD_CPOL                 BIT(9)
#define SPI_CMD_RX_DMA               BIT(10)
#define SPI_CMD_TX_DMA               BIT(11)
#define SPI_CMD_TXMSBF               BIT(12)
#define SPI_CMD_RXMSBF               BIT(13)
#define SPI_CMD_RX_ENDIAN            BIT(14)
#define SPI_CMD_TX_ENDIAN            BIT(15)
#define SPI_CMD_FINISH_IE            BIT(16)
#define SPI_CMD_PAUSE_IE             BIT(17)

#define MT8173_SPI_MAX_PAD_SEL 3

#define MTK_SPI_PAUSE_INT_STATUS 0x2

#define MTK_SPI_IDLE 0
#define MTK_SPI_PAUSED 1

#define MTK_SPI_MAX_FIFO_SIZE 32U
#define MTK_SPI_PACKET_SIZE 1024
#define MTK_SPI_32BITS_MASK  (0xffffffff)

#define DMA_ADDR_EXT_BITS (36)
#define DMA_ADDR_DEF_BITS (32)

struct mtk_spi_compatible {
	bool need_pad_sel;
	/* Must explicitly send dummy Tx bytes to do Rx only transfer */
	bool must_tx;
	/* some IC design adjust cfg register to enhance time accuracy */
	bool enhance_timing;
	/* some IC support DMA addr extension */
	bool dma_ext;
};

struct mtk_spi {
	void __iomem *base;
	u32 state;
	int pad_num;
	u32 *pad_sel;
	struct clk *parent_clk, *sel_clk, *spi_clk;
	struct spi_transfer *cur_transfer;
	u32 xfer_len;
	u32 num_xfered;
	struct scatterlist *tx_sgl, *rx_sgl;
	u32 tx_sgl_len, rx_sgl_len;
	const struct mtk_spi_compatible *dev_comp;
};

static const struct mtk_spi_compatible mtk_common_compat;

static const struct mtk_spi_compatible mt2712_compat = {
	.must_tx = true,
};

static const struct mtk_spi_compatible mt6765_compat = {
	.need_pad_sel = true,
	.must_tx = true,
	.enhance_timing = true,
	.dma_ext = true,
};

static const struct mtk_spi_compatible mt7622_compat = {
	.must_tx = true,
	.enhance_timing = true,
};

static const struct mtk_spi_compatible mt8173_compat = {
	.need_pad_sel = true,
	.must_tx = true,
};

static const struct mtk_spi_compatible mt8183_compat = {
	.need_pad_sel = true,
	.must_tx = true,
	.enhance_timing = true,
};

/*
 * A piece of default chip info unless the platform
 * supplies it.
 */
static const struct mtk_chip_config mtk_default_chip_info = {
	.sample_sel = 0,
};

static const struct of_device_id mtk_spi_of_match[] = {
	{ .compatible = "mediatek,mt2701-spi",
		.data = (void *)&mtk_common_compat,
	},
	{ .compatible = "mediatek,mt2712-spi",
		.data = (void *)&mt2712_compat,
	},
	{ .compatible = "mediatek,mt6589-spi",
		.data = (void *)&mtk_common_compat,
	},
	{ .compatible = "mediatek,mt6765-spi",
		.data = (void *)&mt6765_compat,
	},
	{ .compatible = "mediatek,mt7622-spi",
		.data = (void *)&mt7622_compat,
	},
	{ .compatible = "mediatek,mt7629-spi",
		.data = (void *)&mt7622_compat,
	},
	{ .compatible = "mediatek,mt8135-spi",
		.data = (void *)&mtk_common_compat,
	},
	{ .compatible = "mediatek,mt8173-spi",
		.data = (void *)&mt8173_compat,
	},
	{ .compatible = "mediatek,mt8183-spi",
		.data = (void *)&mt8183_compat,
	},
	{ .compatible = "mediatek,mt8192-spi",
		.data = (void *)&mt6765_compat,
	},
	{}
};
MODULE_DEVICE_TABLE(of, mtk_spi_of_match);

static void mtk_spi_reset(struct mtk_spi *mdata)
{
	u32 reg_val;

	/* set the software reset bit in SPI_CMD_REG. */
	reg_val = readl(mdata->base + SPI_CMD_REG);
	reg_val |= SPI_CMD_RST;
	writel(reg_val, mdata->base + SPI_CMD_REG);

	reg_val = readl(mdata->base + SPI_CMD_REG);
	reg_val &= ~SPI_CMD_RST;
	writel(reg_val, mdata->base + SPI_CMD_REG);
}

static int mtk_spi_prepare_message(struct spi_master *master,
				   struct spi_message *msg)
{
	u16 cpha, cpol;
	u32 reg_val;
	struct spi_device *spi = msg->spi;
	struct mtk_chip_config *chip_config = spi->controller_data;
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	cpha = spi->mode & SPI_CPHA ? 1 : 0;
	cpol = spi->mode & SPI_CPOL ? 1 : 0;

	reg_val = readl(mdata->base + SPI_CMD_REG);
	if (cpha)
		reg_val |= SPI_CMD_CPHA;
	else
		reg_val &= ~SPI_CMD_CPHA;
	if (cpol)
		reg_val |= SPI_CMD_CPOL;
	else
		reg_val &= ~SPI_CMD_CPOL;

	/* set the mlsbx and mlsbtx */
	if (spi->mode & SPI_LSB_FIRST) {
		reg_val &= ~SPI_CMD_TXMSBF;
		reg_val &= ~SPI_CMD_RXMSBF;
	} else {
		reg_val |= SPI_CMD_TXMSBF;
		reg_val |= SPI_CMD_RXMSBF;
	}

	/* set the tx/rx endian */
#ifdef __LITTLE_ENDIAN
	reg_val &= ~SPI_CMD_TX_ENDIAN;
	reg_val &= ~SPI_CMD_RX_ENDIAN;
#else
	reg_val |= SPI_CMD_TX_ENDIAN;
	reg_val |= SPI_CMD_RX_ENDIAN;
#endif

	if (mdata->dev_comp->enhance_timing) {
		/* set CS polarity */
		if (spi->mode & SPI_CS_HIGH)
			reg_val |= SPI_CMD_CS_POL;
		else
			reg_val &= ~SPI_CMD_CS_POL;

		if (chip_config->sample_sel)
			reg_val |= SPI_CMD_SAMPLE_SEL;
		else
			reg_val &= ~SPI_CMD_SAMPLE_SEL;
	}

	/* set finish and pause interrupt always enable */
	reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;

	/* disable dma mode */
	reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);

	/* disable deassert mode */
	reg_val &= ~SPI_CMD_DEASSERT;

	writel(reg_val, mdata->base + SPI_CMD_REG);

	/* pad select */
	if (mdata->dev_comp->need_pad_sel)
		writel(mdata->pad_sel[spi->chip_select],
		       mdata->base + SPI_PAD_SEL_REG);

	return 0;
}

static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
{
	u32 reg_val;
	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);

	if (spi->mode & SPI_CS_HIGH)
		enable = !enable;

	reg_val = readl(mdata->base + SPI_CMD_REG);
	if (!enable) {
		reg_val |= SPI_CMD_PAUSE_EN;
		writel(reg_val, mdata->base + SPI_CMD_REG);
	} else {
		reg_val &= ~SPI_CMD_PAUSE_EN;
		writel(reg_val, mdata->base + SPI_CMD_REG);
		mdata->state = MTK_SPI_IDLE;
		mtk_spi_reset(mdata);
	}
}

static void mtk_spi_prepare_transfer(struct spi_master *master,
				     struct spi_transfer *xfer)
{
	u32 spi_clk_hz, div, sck_time, cs_time, reg_val;
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	spi_clk_hz = clk_get_rate(mdata->spi_clk);
	if (xfer->speed_hz < spi_clk_hz / 2)
		div = DIV_ROUND_UP(spi_clk_hz, xfer->speed_hz);
	else
		div = 1;

	sck_time = (div + 1) / 2;
	cs_time = sck_time * 2;

	if (mdata->dev_comp->enhance_timing) {
		reg_val = (((sck_time - 1) & 0xffff)
			   << SPI_CFG2_SCK_HIGH_OFFSET);
		reg_val |= (((sck_time - 1) & 0xffff)
			   << SPI_CFG2_SCK_LOW_OFFSET);
		writel(reg_val, mdata->base + SPI_CFG2_REG);
		reg_val = (((cs_time - 1) & 0xffff)
			   << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
		reg_val |= (((cs_time - 1) & 0xffff)
			   << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
		writel(reg_val, mdata->base + SPI_CFG0_REG);
	} else {
		reg_val = (((sck_time - 1) & 0xff)
			   << SPI_CFG0_SCK_HIGH_OFFSET);
		reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
		reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
		reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_SETUP_OFFSET);
		writel(reg_val, mdata->base + SPI_CFG0_REG);
	}

	reg_val = readl(mdata->base + SPI_CFG1_REG);
	reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
	reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
	writel(reg_val, mdata->base + SPI_CFG1_REG);
}

static void mtk_spi_setup_packet(struct spi_master *master)
{
	u32 packet_size, packet_loop, reg_val;
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	packet_size = min_t(u32, mdata->xfer_len, MTK_SPI_PACKET_SIZE);
	packet_loop = mdata->xfer_len / packet_size;

	reg_val = readl(mdata->base + SPI_CFG1_REG);
	reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK | SPI_CFG1_PACKET_LOOP_MASK);
	reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
	reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
	writel(reg_val, mdata->base + SPI_CFG1_REG);
}

static void mtk_spi_enable_transfer(struct spi_master *master)
{
	u32 cmd;
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	cmd = readl(mdata->base + SPI_CMD_REG);
	if (mdata->state == MTK_SPI_IDLE)
		cmd |= SPI_CMD_ACT;
	else
		cmd |= SPI_CMD_RESUME;
	writel(cmd, mdata->base + SPI_CMD_REG);
}

static int mtk_spi_get_mult_delta(u32 xfer_len)
{
	u32 mult_delta;

	if (xfer_len > MTK_SPI_PACKET_SIZE)
		mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
	else
		mult_delta = 0;

	return mult_delta;
}

static void mtk_spi_update_mdata_len(struct spi_master *master)
{
	int mult_delta;
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
		if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
			mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
			mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
			mdata->rx_sgl_len = mult_delta;
			mdata->tx_sgl_len -= mdata->xfer_len;
		} else {
			mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
			mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
			mdata->tx_sgl_len = mult_delta;
			mdata->rx_sgl_len -= mdata->xfer_len;
		}
	} else if (mdata->tx_sgl_len) {
		mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
		mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
		mdata->tx_sgl_len = mult_delta;
	} else if (mdata->rx_sgl_len) {
		mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
		mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
		mdata->rx_sgl_len = mult_delta;
	}
}

static void mtk_spi_setup_dma_addr(struct spi_master *master,
				   struct spi_transfer *xfer)
{
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	if (mdata->tx_sgl) {
		writel((u32)(xfer->tx_dma & MTK_SPI_32BITS_MASK),
		       mdata->base + SPI_TX_SRC_REG);
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
		if (mdata->dev_comp->dma_ext)
			writel((u32)(xfer->tx_dma >> 32),
			       mdata->base + SPI_TX_SRC_REG_64);
#endif
	}

	if (mdata->rx_sgl) {
		writel((u32)(xfer->rx_dma & MTK_SPI_32BITS_MASK),
		       mdata->base + SPI_RX_DST_REG);
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
		if (mdata->dev_comp->dma_ext)
			writel((u32)(xfer->rx_dma >> 32),
			       mdata->base + SPI_RX_DST_REG_64);
#endif
	}
}

static int mtk_spi_fifo_transfer(struct spi_master *master,
				 struct spi_device *spi,
				 struct spi_transfer *xfer)
{
	int cnt, remainder;
	u32 reg_val;
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	mdata->cur_transfer = xfer;
	mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, xfer->len);
	mdata->num_xfered = 0;
	mtk_spi_prepare_transfer(master, xfer);
	mtk_spi_setup_packet(master);

	cnt = xfer->len / 4;
	iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);

	remainder = xfer->len % 4;
	if (remainder > 0) {
		reg_val = 0;
		memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
		writel(reg_val, mdata->base + SPI_TX_DATA_REG);
	}

	mtk_spi_enable_transfer(master);

	return 1;
}

static int mtk_spi_dma_transfer(struct spi_master *master,
				struct spi_device *spi,
				struct spi_transfer *xfer)
{
	int cmd;
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	mdata->tx_sgl = NULL;
	mdata->rx_sgl = NULL;
	mdata->tx_sgl_len = 0;
	mdata->rx_sgl_len = 0;
	mdata->cur_transfer = xfer;
	mdata->num_xfered = 0;

	mtk_spi_prepare_transfer(master, xfer);

	cmd = readl(mdata->base + SPI_CMD_REG);
	if (xfer->tx_buf)
		cmd |= SPI_CMD_TX_DMA;
	if (xfer->rx_buf)
		cmd |= SPI_CMD_RX_DMA;
	writel(cmd, mdata->base + SPI_CMD_REG);

	if (xfer->tx_buf)
		mdata->tx_sgl = xfer->tx_sg.sgl;
	if (xfer->rx_buf)
		mdata->rx_sgl = xfer->rx_sg.sgl;

	if (mdata->tx_sgl) {
		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
	}
	if (mdata->rx_sgl) {
		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
	}

	mtk_spi_update_mdata_len(master);
	mtk_spi_setup_packet(master);
	mtk_spi_setup_dma_addr(master, xfer);
	mtk_spi_enable_transfer(master);

	return 1;
}

static int mtk_spi_transfer_one(struct spi_master *master,
				struct spi_device *spi,
				struct spi_transfer *xfer)
{
	if (master->can_dma(master, spi, xfer))
		return mtk_spi_dma_transfer(master, spi, xfer);
	else
		return mtk_spi_fifo_transfer(master, spi, xfer);
}

static bool mtk_spi_can_dma(struct spi_master *master,
			    struct spi_device *spi,
			    struct spi_transfer *xfer)
{
	/* Buffers for DMA transactions must be 4-byte aligned */
	return (xfer->len > MTK_SPI_MAX_FIFO_SIZE &&
		(unsigned long)xfer->tx_buf % 4 == 0 &&
		(unsigned long)xfer->rx_buf % 4 == 0);
}

static int mtk_spi_setup(struct spi_device *spi)
{
	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);

	if (!spi->controller_data)
		spi->controller_data = (void *)&mtk_default_chip_info;

	if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));

	return 0;
}

static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
{
	u32 cmd, reg_val, cnt, remainder, len;
	struct spi_master *master = dev_id;
	struct mtk_spi *mdata = spi_master_get_devdata(master);
	struct spi_transfer *trans = mdata->cur_transfer;

	reg_val = readl(mdata->base + SPI_STATUS0_REG);
	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
		mdata->state = MTK_SPI_PAUSED;
	else
		mdata->state = MTK_SPI_IDLE;

	if (!master->can_dma(master, master->cur_msg->spi, trans)) {
		if (trans->rx_buf) {
			cnt = mdata->xfer_len / 4;
			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
				     trans->rx_buf + mdata->num_xfered, cnt);
			remainder = mdata->xfer_len % 4;
			if (remainder > 0) {
				reg_val = readl(mdata->base + SPI_RX_DATA_REG);
				memcpy(trans->rx_buf +
					mdata->num_xfered +
					(cnt * 4),
					&reg_val,
					remainder);
			}
		}

		mdata->num_xfered += mdata->xfer_len;
		if (mdata->num_xfered == trans->len) {
			spi_finalize_current_transfer(master);
			return IRQ_HANDLED;
		}

		len = trans->len - mdata->num_xfered;
		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len);
		mtk_spi_setup_packet(master);

		cnt = mdata->xfer_len / 4;
		iowrite32_rep(mdata->base + SPI_TX_DATA_REG,
				trans->tx_buf + mdata->num_xfered, cnt);

		remainder = mdata->xfer_len % 4;
		if (remainder > 0) {
			reg_val = 0;
			memcpy(&reg_val,
				trans->tx_buf + (cnt * 4) + mdata->num_xfered,
				remainder);
			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
		}

		mtk_spi_enable_transfer(master);

		return IRQ_HANDLED;
	}

	if (mdata->tx_sgl)
		trans->tx_dma += mdata->xfer_len;
	if (mdata->rx_sgl)
		trans->rx_dma += mdata->xfer_len;

	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
		mdata->tx_sgl = sg_next(mdata->tx_sgl);
		if (mdata->tx_sgl) {
			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
		}
	}
	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
		mdata->rx_sgl = sg_next(mdata->rx_sgl);
		if (mdata->rx_sgl) {
			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
		}
	}

	if (!mdata->tx_sgl && !mdata->rx_sgl) {
		/* spi disable dma */
		cmd = readl(mdata->base + SPI_CMD_REG);
		cmd &= ~SPI_CMD_TX_DMA;
		cmd &= ~SPI_CMD_RX_DMA;
		writel(cmd, mdata->base + SPI_CMD_REG);

		spi_finalize_current_transfer(master);
		return IRQ_HANDLED;
	}

	mtk_spi_update_mdata_len(master);
	mtk_spi_setup_packet(master);
	mtk_spi_setup_dma_addr(master, trans);
	mtk_spi_enable_transfer(master);

	return IRQ_HANDLED;
}

static int mtk_spi_probe(struct platform_device *pdev)
{
	struct spi_master *master;
	struct mtk_spi *mdata;
	const struct of_device_id *of_id;
	int i, irq, ret, addr_bits;

	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
	if (!master) {
		dev_err(&pdev->dev, "failed to alloc spi master\n");
		return -ENOMEM;
	}

	master->auto_runtime_pm = true;
	master->dev.of_node = pdev->dev.of_node;
	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;

	master->set_cs = mtk_spi_set_cs;
	master->prepare_message = mtk_spi_prepare_message;
	master->transfer_one = mtk_spi_transfer_one;
	master->can_dma = mtk_spi_can_dma;
	master->setup = mtk_spi_setup;

	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
	if (!of_id) {
		dev_err(&pdev->dev, "failed to probe of_node\n");
		ret = -EINVAL;
		goto err_put_master;
	}

	mdata = spi_master_get_devdata(master);
	mdata->dev_comp = of_id->data;

	if (mdata->dev_comp->enhance_timing)
		master->mode_bits |= SPI_CS_HIGH;

	if (mdata->dev_comp->must_tx)
		master->flags = SPI_MASTER_MUST_TX;

	if (mdata->dev_comp->need_pad_sel) {
		mdata->pad_num = of_property_count_u32_elems(
			pdev->dev.of_node,
			"mediatek,pad-select");
		if (mdata->pad_num < 0) {
			dev_err(&pdev->dev,
				"No 'mediatek,pad-select' property\n");
			ret = -EINVAL;
			goto err_put_master;
		}

		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
						    sizeof(u32), GFP_KERNEL);
		if (!mdata->pad_sel) {
			ret = -ENOMEM;
			goto err_put_master;
		}

		for (i = 0; i < mdata->pad_num; i++) {
			of_property_read_u32_index(pdev->dev.of_node,
						   "mediatek,pad-select",
						   i, &mdata->pad_sel[i]);
			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
					i, mdata->pad_sel[i]);
				ret = -EINVAL;
				goto err_put_master;
			}
		}
	}

	platform_set_drvdata(pdev, master);
	mdata->base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(mdata->base)) {
		ret = PTR_ERR(mdata->base);
		goto err_put_master;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		ret = irq;
		goto err_put_master;
	}

	if (!pdev->dev.dma_mask)
		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;

	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
	if (ret) {
		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
		goto err_put_master;
	}

	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
	if (IS_ERR(mdata->parent_clk)) {
		ret = PTR_ERR(mdata->parent_clk);
		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
		goto err_put_master;
	}

	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
	if (IS_ERR(mdata->sel_clk)) {
		ret = PTR_ERR(mdata->sel_clk);
		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
		goto err_put_master;
	}

	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
	if (IS_ERR(mdata->spi_clk)) {
		ret = PTR_ERR(mdata->spi_clk);
		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
		goto err_put_master;
	}

	ret = clk_prepare_enable(mdata->spi_clk);
	if (ret < 0) {
		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
		goto err_put_master;
	}

	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
	if (ret < 0) {
		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
		clk_disable_unprepare(mdata->spi_clk);
		goto err_put_master;
	}

	clk_disable_unprepare(mdata->spi_clk);

	pm_runtime_enable(&pdev->dev);

	ret = devm_spi_register_master(&pdev->dev, master);
	if (ret) {
		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
		goto err_disable_runtime_pm;
	}

	if (mdata->dev_comp->need_pad_sel) {
		if (mdata->pad_num != master->num_chipselect) {
			dev_err(&pdev->dev,
				"pad_num does not match num_chipselect(%d != %d)\n",
				mdata->pad_num, master->num_chipselect);
			ret = -EINVAL;
			goto err_disable_runtime_pm;
		}

		if (!master->cs_gpios && master->num_chipselect > 1) {
			dev_err(&pdev->dev,
				"cs_gpios not specified and num_chipselect > 1\n");
			ret = -EINVAL;
			goto err_disable_runtime_pm;
		}

		if (master->cs_gpios) {
			for (i = 0; i < master->num_chipselect; i++) {
				ret = devm_gpio_request(&pdev->dev,
							master->cs_gpios[i],
							dev_name(&pdev->dev));
				if (ret) {
					dev_err(&pdev->dev,
						"can't get CS GPIO %i\n", i);
					goto err_disable_runtime_pm;
				}
			}
		}
	}

	if (mdata->dev_comp->dma_ext)
		addr_bits = DMA_ADDR_EXT_BITS;
	else
		addr_bits = DMA_ADDR_DEF_BITS;
	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(addr_bits));
	if (ret)
		dev_notice(&pdev->dev, "SPI dma_set_mask(%d) failed, ret:%d\n",
			   addr_bits, ret);

	return 0;

err_disable_runtime_pm:
	pm_runtime_disable(&pdev->dev);
err_put_master:
	spi_master_put(master);

	return ret;
}

static int mtk_spi_remove(struct platform_device *pdev)
{
	struct spi_master *master = platform_get_drvdata(pdev);
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	pm_runtime_disable(&pdev->dev);

	mtk_spi_reset(mdata);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int mtk_spi_suspend(struct device *dev)
{
	int ret;
	struct spi_master *master = dev_get_drvdata(dev);
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	ret = spi_master_suspend(master);
	if (ret)
		return ret;

	if (!pm_runtime_suspended(dev))
		clk_disable_unprepare(mdata->spi_clk);

	return ret;
}

static int mtk_spi_resume(struct device *dev)
{
	int ret;
	struct spi_master *master = dev_get_drvdata(dev);
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	if (!pm_runtime_suspended(dev)) {
		ret = clk_prepare_enable(mdata->spi_clk);
		if (ret < 0) {
			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
			return ret;
		}
	}

	ret = spi_master_resume(master);
	if (ret < 0)
		clk_disable_unprepare(mdata->spi_clk);

	return ret;
}
#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_PM
static int mtk_spi_runtime_suspend(struct device *dev)
{
	struct spi_master *master = dev_get_drvdata(dev);
	struct mtk_spi *mdata = spi_master_get_devdata(master);

	clk_disable_unprepare(mdata->spi_clk);

	return 0;
}

static int mtk_spi_runtime_resume(struct device *dev)
{
	struct spi_master *master = dev_get_drvdata(dev);
	struct mtk_spi *mdata = spi_master_get_devdata(master);
	int ret;

	ret = clk_prepare_enable(mdata->spi_clk);
	if (ret < 0) {
		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
		return ret;
	}

	return 0;
}
#endif /* CONFIG_PM */

static const struct dev_pm_ops mtk_spi_pm = {
	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
			   mtk_spi_runtime_resume, NULL)
};

static struct platform_driver mtk_spi_driver = {
	.driver = {
		.name = "mtk-spi",
		.pm	= &mtk_spi_pm,
		.of_match_table = mtk_spi_of_match,
	},
	.probe = mtk_spi_probe,
	.remove = mtk_spi_remove,
};

module_platform_driver(mtk_spi_driver);

MODULE_DESCRIPTION("MTK SPI Controller driver");
MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:mtk-spi");