aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-pxa2xx.c
blob: cc42ee5e19fba4a54ff41d3a7472de494f22b0e9 (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
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
/*
 * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
 * Copyright (C) 2013, Intel Corporation
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/ioport.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/spi/pxa2xx_spi.h>
#include <linux/spi/spi.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/pm_runtime.h>
#include <linux/acpi.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/delay.h>

#include "spi-pxa2xx.h"

MODULE_AUTHOR("Stephen Street");
MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pxa2xx-spi");

#define MAX_BUSES 3

#define TIMOUT_DFLT		1000

/*
 * for testing SSCR1 changes that require SSP restart, basically
 * everything except the service and interrupt enables, the pxa270 developer
 * manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
 * list, but the PXA255 dev man says all bits without really meaning the
 * service and interrupt enables
 */
#define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
				| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
				| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
				| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
				| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
				| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)

#define LPSS_RX_THRESH_DFLT	64
#define LPSS_TX_LOTHRESH_DFLT	160
#define LPSS_TX_HITHRESH_DFLT	224

/* Offset from drv_data->lpss_base */
#define SSP_REG			0x0c
#define SPI_CS_CONTROL		0x18
#define SPI_CS_CONTROL_SW_MODE	BIT(0)
#define SPI_CS_CONTROL_CS_HIGH	BIT(1)

static bool is_lpss_ssp(const struct driver_data *drv_data)
{
	return drv_data->ssp_type == LPSS_SSP;
}

/*
 * Read and write LPSS SSP private registers. Caller must first check that
 * is_lpss_ssp() returns true before these can be called.
 */
static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
{
	WARN_ON(!drv_data->lpss_base);
	return readl(drv_data->lpss_base + offset);
}

static void __lpss_ssp_write_priv(struct driver_data *drv_data,
				  unsigned offset, u32 value)
{
	WARN_ON(!drv_data->lpss_base);
	writel(value, drv_data->lpss_base + offset);
}

/*
 * lpss_ssp_setup - perform LPSS SSP specific setup
 * @drv_data: pointer to the driver private data
 *
 * Perform LPSS SSP specific setup. This function must be called first if
 * one is going to use LPSS SSP private registers.
 */
static void lpss_ssp_setup(struct driver_data *drv_data)
{
	unsigned offset = 0x400;
	u32 value, orig;

	if (!is_lpss_ssp(drv_data))
		return;

	/*
	 * Perform auto-detection of the LPSS SSP private registers. They
	 * can be either at 1k or 2k offset from the base address.
	 */
	orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);

	value = orig | SPI_CS_CONTROL_SW_MODE;
	writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
	value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
	if (value != (orig | SPI_CS_CONTROL_SW_MODE)) {
		offset = 0x800;
		goto detection_done;
	}

	value &= ~SPI_CS_CONTROL_SW_MODE;
	writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL);
	value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL);
	if (value != orig) {
		offset = 0x800;
		goto detection_done;
	}

detection_done:
	/* Now set the LPSS base */
	drv_data->lpss_base = drv_data->ioaddr + offset;

	/* Enable software chip select control */
	value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH;
	__lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);

	/* Enable multiblock DMA transfers */
	if (drv_data->master_info->enable_dma)
		__lpss_ssp_write_priv(drv_data, SSP_REG, 1);
}

static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
{
	u32 value;

	if (!is_lpss_ssp(drv_data))
		return;

	value = __lpss_ssp_read_priv(drv_data, SPI_CS_CONTROL);
	if (enable)
		value &= ~SPI_CS_CONTROL_CS_HIGH;
	else
		value |= SPI_CS_CONTROL_CS_HIGH;
	__lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value);
}

static void cs_assert(struct driver_data *drv_data)
{
	struct chip_data *chip = drv_data->cur_chip;

	if (drv_data->ssp_type == CE4100_SSP) {
		write_SSSR(drv_data->cur_chip->frm, drv_data->ioaddr);
		return;
	}

	if (chip->cs_control) {
		chip->cs_control(PXA2XX_CS_ASSERT);
		return;
	}

	if (gpio_is_valid(chip->gpio_cs)) {
		gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
		return;
	}

	lpss_ssp_cs_control(drv_data, true);
}

static void cs_deassert(struct driver_data *drv_data)
{
	struct chip_data *chip = drv_data->cur_chip;

	if (drv_data->ssp_type == CE4100_SSP)
		return;

	if (chip->cs_control) {
		chip->cs_control(PXA2XX_CS_DEASSERT);
		return;
	}

	if (gpio_is_valid(chip->gpio_cs)) {
		gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
		return;
	}

	lpss_ssp_cs_control(drv_data, false);
}

int pxa2xx_spi_flush(struct driver_data *drv_data)
{
	unsigned long limit = loops_per_jiffy << 1;

	void __iomem *reg = drv_data->ioaddr;

	do {
		while (read_SSSR(reg) & SSSR_RNE) {
			read_SSDR(reg);
		}
	} while ((read_SSSR(reg) & SSSR_BSY) && --limit);
	write_SSSR_CS(drv_data, SSSR_ROR);

	return limit;
}

static int null_writer(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;
	u8 n_bytes = drv_data->n_bytes;

	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
		|| (drv_data->tx == drv_data->tx_end))
		return 0;

	write_SSDR(0, reg);
	drv_data->tx += n_bytes;

	return 1;
}

static int null_reader(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;
	u8 n_bytes = drv_data->n_bytes;

	while ((read_SSSR(reg) & SSSR_RNE)
		&& (drv_data->rx < drv_data->rx_end)) {
		read_SSDR(reg);
		drv_data->rx += n_bytes;
	}

	return drv_data->rx == drv_data->rx_end;
}

static int u8_writer(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
		|| (drv_data->tx == drv_data->tx_end))
		return 0;

	write_SSDR(*(u8 *)(drv_data->tx), reg);
	++drv_data->tx;

	return 1;
}

static int u8_reader(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	while ((read_SSSR(reg) & SSSR_RNE)
		&& (drv_data->rx < drv_data->rx_end)) {
		*(u8 *)(drv_data->rx) = read_SSDR(reg);
		++drv_data->rx;
	}

	return drv_data->rx == drv_data->rx_end;
}

static int u16_writer(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
		|| (drv_data->tx == drv_data->tx_end))
		return 0;

	write_SSDR(*(u16 *)(drv_data->tx), reg);
	drv_data->tx += 2;

	return 1;
}

static int u16_reader(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	while ((read_SSSR(reg) & SSSR_RNE)
		&& (drv_data->rx < drv_data->rx_end)) {
		*(u16 *)(drv_data->rx) = read_SSDR(reg);
		drv_data->rx += 2;
	}

	return drv_data->rx == drv_data->rx_end;
}

static int u32_writer(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	if (((read_SSSR(reg) & SSSR_TFL_MASK) == SSSR_TFL_MASK)
		|| (drv_data->tx == drv_data->tx_end))
		return 0;

	write_SSDR(*(u32 *)(drv_data->tx), reg);
	drv_data->tx += 4;

	return 1;
}

static int u32_reader(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	while ((read_SSSR(reg) & SSSR_RNE)
		&& (drv_data->rx < drv_data->rx_end)) {
		*(u32 *)(drv_data->rx) = read_SSDR(reg);
		drv_data->rx += 4;
	}

	return drv_data->rx == drv_data->rx_end;
}

void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
{
	struct spi_message *msg = drv_data->cur_msg;
	struct spi_transfer *trans = drv_data->cur_transfer;

	/* Move to next transfer */
	if (trans->transfer_list.next != &msg->transfers) {
		drv_data->cur_transfer =
			list_entry(trans->transfer_list.next,
					struct spi_transfer,
					transfer_list);
		return RUNNING_STATE;
	} else
		return DONE_STATE;
}

/* caller already set message->status; dma and pio irqs are blocked */
static void giveback(struct driver_data *drv_data)
{
	struct spi_transfer* last_transfer;
	struct spi_message *msg;

	msg = drv_data->cur_msg;
	drv_data->cur_msg = NULL;
	drv_data->cur_transfer = NULL;

	last_transfer = list_entry(msg->transfers.prev,
					struct spi_transfer,
					transfer_list);

	/* Delay if requested before any change in chip select */
	if (last_transfer->delay_usecs)
		udelay(last_transfer->delay_usecs);

	/* Drop chip select UNLESS cs_change is true or we are returning
	 * a message with an error, or next message is for another chip
	 */
	if (!last_transfer->cs_change)
		cs_deassert(drv_data);
	else {
		struct spi_message *next_msg;

		/* Holding of cs was hinted, but we need to make sure
		 * the next message is for the same chip.  Don't waste
		 * time with the following tests unless this was hinted.
		 *
		 * We cannot postpone this until pump_messages, because
		 * after calling msg->complete (below) the driver that
		 * sent the current message could be unloaded, which
		 * could invalidate the cs_control() callback...
		 */

		/* get a pointer to the next message, if any */
		next_msg = spi_get_next_queued_message(drv_data->master);

		/* see if the next and current messages point
		 * to the same chip
		 */
		if (next_msg && next_msg->spi != msg->spi)
			next_msg = NULL;
		if (!next_msg || msg->state == ERROR_STATE)
			cs_deassert(drv_data);
	}

	drv_data->cur_chip = NULL;
	spi_finalize_current_message(drv_data->master);
}

static void reset_sccr1(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;
	struct chip_data *chip = drv_data->cur_chip;
	u32 sccr1_reg;

	sccr1_reg = read_SSCR1(reg) & ~drv_data->int_cr1;
	sccr1_reg &= ~SSCR1_RFT;
	sccr1_reg |= chip->threshold;
	write_SSCR1(sccr1_reg, reg);
}

static void int_error_stop(struct driver_data *drv_data, const char* msg)
{
	void __iomem *reg = drv_data->ioaddr;

	/* Stop and reset SSP */
	write_SSSR_CS(drv_data, drv_data->clear_sr);
	reset_sccr1(drv_data);
	if (!pxa25x_ssp_comp(drv_data))
		write_SSTO(0, reg);
	pxa2xx_spi_flush(drv_data);
	write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);

	dev_err(&drv_data->pdev->dev, "%s\n", msg);

	drv_data->cur_msg->state = ERROR_STATE;
	tasklet_schedule(&drv_data->pump_transfers);
}

static void int_transfer_complete(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	/* Stop SSP */
	write_SSSR_CS(drv_data, drv_data->clear_sr);
	reset_sccr1(drv_data);
	if (!pxa25x_ssp_comp(drv_data))
		write_SSTO(0, reg);

	/* Update total byte transferred return count actual bytes read */
	drv_data->cur_msg->actual_length += drv_data->len -
				(drv_data->rx_end - drv_data->rx);

	/* Transfer delays and chip select release are
	 * handled in pump_transfers or giveback
	 */

	/* Move to next transfer */
	drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);

	/* Schedule transfer tasklet */
	tasklet_schedule(&drv_data->pump_transfers);
}

static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
{
	void __iomem *reg = drv_data->ioaddr;

	u32 irq_mask = (read_SSCR1(reg) & SSCR1_TIE) ?
			drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;

	u32 irq_status = read_SSSR(reg) & irq_mask;

	if (irq_status & SSSR_ROR) {
		int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
		return IRQ_HANDLED;
	}

	if (irq_status & SSSR_TINT) {
		write_SSSR(SSSR_TINT, reg);
		if (drv_data->read(drv_data)) {
			int_transfer_complete(drv_data);
			return IRQ_HANDLED;
		}
	}

	/* Drain rx fifo, Fill tx fifo and prevent overruns */
	do {
		if (drv_data->read(drv_data)) {
			int_transfer_complete(drv_data);
			return IRQ_HANDLED;
		}
	} while (drv_data->write(drv_data));

	if (drv_data->read(drv_data)) {
		int_transfer_complete(drv_data);
		return IRQ_HANDLED;
	}

	if (drv_data->tx == drv_data->tx_end) {
		u32 bytes_left;
		u32 sccr1_reg;

		sccr1_reg = read_SSCR1(reg);
		sccr1_reg &= ~SSCR1_TIE;

		/*
		 * PXA25x_SSP has no timeout, set up rx threshould for the
		 * remaining RX bytes.
		 */
		if (pxa25x_ssp_comp(drv_data)) {

			sccr1_reg &= ~SSCR1_RFT;

			bytes_left = drv_data->rx_end - drv_data->rx;
			switch (drv_data->n_bytes) {
			case 4:
				bytes_left >>= 1;
			case 2:
				bytes_left >>= 1;
			}

			if (bytes_left > RX_THRESH_DFLT)
				bytes_left = RX_THRESH_DFLT;

			sccr1_reg |= SSCR1_RxTresh(bytes_left);
		}
		write_SSCR1(sccr1_reg, reg);
	}

	/* We did something */
	return IRQ_HANDLED;
}

static irqreturn_t ssp_int(int irq, void *dev_id)
{
	struct driver_data *drv_data = dev_id;
	void __iomem *reg = drv_data->ioaddr;
	u32 sccr1_reg;
	u32 mask = drv_data->mask_sr;
	u32 status;

	/*
	 * The IRQ might be shared with other peripherals so we must first
	 * check that are we RPM suspended or not. If we are we assume that
	 * the IRQ was not for us (we shouldn't be RPM suspended when the
	 * interrupt is enabled).
	 */
	if (pm_runtime_suspended(&drv_data->pdev->dev))
		return IRQ_NONE;

	sccr1_reg = read_SSCR1(reg);
	status = read_SSSR(reg);

	/* Ignore possible writes if we don't need to write */
	if (!(sccr1_reg & SSCR1_TIE))
		mask &= ~SSSR_TFS;

	if (!(status & mask))
		return IRQ_NONE;

	if (!drv_data->cur_msg) {

		write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg);
		write_SSCR1(read_SSCR1(reg) & ~drv_data->int_cr1, reg);
		if (!pxa25x_ssp_comp(drv_data))
			write_SSTO(0, reg);
		write_SSSR_CS(drv_data, drv_data->clear_sr);

		dev_err(&drv_data->pdev->dev, "bad message state "
			"in interrupt handler\n");

		/* Never fail */
		return IRQ_HANDLED;
	}

	return drv_data->transfer_handler(drv_data);
}

static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
{
	unsigned long ssp_clk = drv_data->max_clk_rate;
	const struct ssp_device *ssp = drv_data->ssp;

	rate = min_t(int, ssp_clk, rate);

	if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
		return ((ssp_clk / (2 * rate) - 1) & 0xff) << 8;
	else
		return ((ssp_clk / rate - 1) & 0xfff) << 8;
}

static void pump_transfers(unsigned long data)
{
	struct driver_data *drv_data = (struct driver_data *)data;
	struct spi_message *message = NULL;
	struct spi_transfer *transfer = NULL;
	struct spi_transfer *previous = NULL;
	struct chip_data *chip = NULL;
	void __iomem *reg = drv_data->ioaddr;
	u32 clk_div = 0;
	u8 bits = 0;
	u32 speed = 0;
	u32 cr0;
	u32 cr1;
	u32 dma_thresh = drv_data->cur_chip->dma_threshold;
	u32 dma_burst = drv_data->cur_chip->dma_burst_size;

	/* Get current state information */
	message = drv_data->cur_msg;
	transfer = drv_data->cur_transfer;
	chip = drv_data->cur_chip;

	/* Handle for abort */
	if (message->state == ERROR_STATE) {
		message->status = -EIO;
		giveback(drv_data);
		return;
	}

	/* Handle end of message */
	if (message->state == DONE_STATE) {
		message->status = 0;
		giveback(drv_data);
		return;
	}

	/* Delay if requested at end of transfer before CS change */
	if (message->state == RUNNING_STATE) {
		previous = list_entry(transfer->transfer_list.prev,
					struct spi_transfer,
					transfer_list);
		if (previous->delay_usecs)
			udelay(previous->delay_usecs);

		/* Drop chip select only if cs_change is requested */
		if (previous->cs_change)
			cs_deassert(drv_data);
	}

	/* Check if we can DMA this transfer */
	if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) {

		/* reject already-mapped transfers; PIO won't always work */
		if (message->is_dma_mapped
				|| transfer->rx_dma || transfer->tx_dma) {
			dev_err(&drv_data->pdev->dev,
				"pump_transfers: mapped transfer length "
				"of %u is greater than %d\n",
				transfer->len, MAX_DMA_LEN);
			message->status = -EINVAL;
			giveback(drv_data);
			return;
		}

		/* warn ... we force this to PIO mode */
		if (printk_ratelimit())
			dev_warn(&message->spi->dev, "pump_transfers: "
				"DMA disabled for transfer length %ld "
				"greater than %d\n",
				(long)drv_data->len, MAX_DMA_LEN);
	}

	/* Setup the transfer state based on the type of transfer */
	if (pxa2xx_spi_flush(drv_data) == 0) {
		dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
		message->status = -EIO;
		giveback(drv_data);
		return;
	}
	drv_data->n_bytes = chip->n_bytes;
	drv_data->tx = (void *)transfer->tx_buf;
	drv_data->tx_end = drv_data->tx + transfer->len;
	drv_data->rx = transfer->rx_buf;
	drv_data->rx_end = drv_data->rx + transfer->len;
	drv_data->rx_dma = transfer->rx_dma;
	drv_data->tx_dma = transfer->tx_dma;
	drv_data->len = transfer->len;
	drv_data->write = drv_data->tx ? chip->write : null_writer;
	drv_data->read = drv_data->rx ? chip->read : null_reader;

	/* Change speed and bit per word on a per transfer */
	cr0 = chip->cr0;
	if (transfer->speed_hz || transfer->bits_per_word) {

		bits = chip->bits_per_word;
		speed = chip->speed_hz;

		if (transfer->speed_hz)
			speed = transfer->speed_hz;

		if (transfer->bits_per_word)
			bits = transfer->bits_per_word;

		clk_div = ssp_get_clk_div(drv_data, speed);

		if (bits <= 8) {
			drv_data->n_bytes = 1;
			drv_data->read = drv_data->read != null_reader ?
						u8_reader : null_reader;
			drv_data->write = drv_data->write != null_writer ?
						u8_writer : null_writer;
		} else if (bits <= 16) {
			drv_data->n_bytes = 2;
			drv_data->read = drv_data->read != null_reader ?
						u16_reader : null_reader;
			drv_data->write = drv_data->write != null_writer ?
						u16_writer : null_writer;
		} else if (bits <= 32) {
			drv_data->n_bytes = 4;
			drv_data->read = drv_data->read != null_reader ?
						u32_reader : null_reader;
			drv_data->write = drv_data->write != null_writer ?
						u32_writer : null_writer;
		}
		/* if bits/word is changed in dma mode, then must check the
		 * thresholds and burst also */
		if (chip->enable_dma) {
			if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
							message->spi,
							bits, &dma_burst,
							&dma_thresh))
				if (printk_ratelimit())
					dev_warn(&message->spi->dev,
						"pump_transfers: "
						"DMA burst size reduced to "
						"match bits_per_word\n");
		}

		cr0 = clk_div
			| SSCR0_Motorola
			| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
			| SSCR0_SSE
			| (bits > 16 ? SSCR0_EDSS : 0);
	}

	message->state = RUNNING_STATE;

	drv_data->dma_mapped = 0;
	if (pxa2xx_spi_dma_is_possible(drv_data->len))
		drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data);
	if (drv_data->dma_mapped) {

		/* Ensure we have the correct interrupt handler */
		drv_data->transfer_handler = pxa2xx_spi_dma_transfer;

		pxa2xx_spi_dma_prepare(drv_data, dma_burst);

		/* Clear status and start DMA engine */
		cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
		write_SSSR(drv_data->clear_sr, reg);

		pxa2xx_spi_dma_start(drv_data);
	} else {
		/* Ensure we have the correct interrupt handler	*/
		drv_data->transfer_handler = interrupt_transfer;

		/* Clear status  */
		cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
		write_SSSR_CS(drv_data, drv_data->clear_sr);
	}

	if (is_lpss_ssp(drv_data)) {
		if ((read_SSIRF(reg) & 0xff) != chip->lpss_rx_threshold)
			write_SSIRF(chip->lpss_rx_threshold, reg);
		if ((read_SSITF(reg) & 0xffff) != chip->lpss_tx_threshold)
			write_SSITF(chip->lpss_tx_threshold, reg);
	}

	/* see if we need to reload the config registers */
	if ((read_SSCR0(reg) != cr0)
		|| (read_SSCR1(reg) & SSCR1_CHANGE_MASK) !=
			(cr1 & SSCR1_CHANGE_MASK)) {

		/* stop the SSP, and update the other bits */
		write_SSCR0(cr0 & ~SSCR0_SSE, reg);
		if (!pxa25x_ssp_comp(drv_data))
			write_SSTO(chip->timeout, reg);
		/* first set CR1 without interrupt and service enables */
		write_SSCR1(cr1 & SSCR1_CHANGE_MASK, reg);
		/* restart the SSP */
		write_SSCR0(cr0, reg);

	} else {
		if (!pxa25x_ssp_comp(drv_data))
			write_SSTO(chip->timeout, reg);
	}

	cs_assert(drv_data);

	/* after chip select, release the data by enabling service
	 * requests and interrupts, without changing any mode bits */
	write_SSCR1(cr1, reg);
}

static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
					   struct spi_message *msg)
{
	struct driver_data *drv_data = spi_master_get_devdata(master);

	drv_data->cur_msg = msg;
	/* Initial message state*/
	drv_data->cur_msg->state = START_STATE;
	drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
						struct spi_transfer,
						transfer_list);

	/* prepare to setup the SSP, in pump_transfers, using the per
	 * chip configuration */
	drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);

	/* Mark as busy and launch transfers */
	tasklet_schedule(&drv_data->pump_transfers);
	return 0;
}

static int pxa2xx_spi_prepare_transfer(struct spi_master *master)
{
	struct driver_data *drv_data = spi_master_get_devdata(master);

	pm_runtime_get_sync(&drv_data->pdev->dev);
	return 0;
}

static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
{
	struct driver_data *drv_data = spi_master_get_devdata(master);

	/* Disable the SSP now */
	write_SSCR0(read_SSCR0(drv_data->ioaddr) & ~SSCR0_SSE,
		    drv_data->ioaddr);

	pm_runtime_mark_last_busy(&drv_data->pdev->dev);
	pm_runtime_put_autosuspend(&drv_data->pdev->dev);
	return 0;
}

static int setup_cs(struct spi_device *spi, struct chip_data *chip,
		    struct pxa2xx_spi_chip *chip_info)
{
	int err = 0;

	if (chip == NULL || chip_info == NULL)
		return 0;

	/* NOTE: setup() can be called multiple times, possibly with
	 * different chip_info, release previously requested GPIO
	 */
	if (gpio_is_valid(chip->gpio_cs))
		gpio_free(chip->gpio_cs);

	/* If (*cs_control) is provided, ignore GPIO chip select */
	if (chip_info->cs_control) {
		chip->cs_control = chip_info->cs_control;
		return 0;
	}

	if (gpio_is_valid(chip_info->gpio_cs)) {
		err = gpio_request(chip_info->gpio_cs, "SPI_CS");
		if (err) {
			dev_err(&spi->dev, "failed to request chip select "
					"GPIO%d\n", chip_info->gpio_cs);
			return err;
		}

		chip->gpio_cs = chip_info->gpio_cs;
		chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;

		err = gpio_direction_output(chip->gpio_cs,
					!chip->gpio_cs_inverted);
	}

	return err;
}

static int setup(struct spi_device *spi)
{
	struct pxa2xx_spi_chip *chip_info = NULL;
	struct chip_data *chip;
	struct driver_data *drv_data = spi_master_get_devdata(spi->master);
	unsigned int clk_div;
	uint tx_thres, tx_hi_thres, rx_thres;

	if (is_lpss_ssp(drv_data)) {
		tx_thres = LPSS_TX_LOTHRESH_DFLT;
		tx_hi_thres = LPSS_TX_HITHRESH_DFLT;
		rx_thres = LPSS_RX_THRESH_DFLT;
	} else {
		tx_thres = TX_THRESH_DFLT;
		tx_hi_thres = 0;
		rx_thres = RX_THRESH_DFLT;
	}

	if (!pxa25x_ssp_comp(drv_data)
		&& (spi->bits_per_word < 4 || spi->bits_per_word > 32)) {
		dev_err(&spi->dev, "failed setup: ssp_type=%d, bits/wrd=%d "
				"b/w not 4-32 for type non-PXA25x_SSP\n",
				drv_data->ssp_type, spi->bits_per_word);
		return -EINVAL;
	} else if (pxa25x_ssp_comp(drv_data)
			&& (spi->bits_per_word < 4
				|| spi->bits_per_word > 16)) {
		dev_err(&spi->dev, "failed setup: ssp_type=%d, bits/wrd=%d "
				"b/w not 4-16 for type PXA25x_SSP\n",
				drv_data->ssp_type, spi->bits_per_word);
		return -EINVAL;
	}

	/* Only alloc on first setup */
	chip = spi_get_ctldata(spi);
	if (!chip) {
		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
		if (!chip) {
			dev_err(&spi->dev,
				"failed setup: can't allocate chip data\n");
			return -ENOMEM;
		}

		if (drv_data->ssp_type == CE4100_SSP) {
			if (spi->chip_select > 4) {
				dev_err(&spi->dev, "failed setup: "
				"cs number must not be > 4.\n");
				kfree(chip);
				return -EINVAL;
			}

			chip->frm = spi->chip_select;
		} else
			chip->gpio_cs = -1;
		chip->enable_dma = 0;
		chip->timeout = TIMOUT_DFLT;
	}

	/* protocol drivers may change the chip settings, so...
	 * if chip_info exists, use it */
	chip_info = spi->controller_data;

	/* chip_info isn't always needed */
	chip->cr1 = 0;
	if (chip_info) {
		if (chip_info->timeout)
			chip->timeout = chip_info->timeout;
		if (chip_info->tx_threshold)
			tx_thres = chip_info->tx_threshold;
		if (chip_info->tx_hi_threshold)
			tx_hi_thres = chip_info->tx_hi_threshold;
		if (chip_info->rx_threshold)
			rx_thres = chip_info->rx_threshold;
		chip->enable_dma = drv_data->master_info->enable_dma;
		chip->dma_threshold = 0;
		if (chip_info->enable_loopback)
			chip->cr1 = SSCR1_LBM;
	} else if (ACPI_HANDLE(&spi->dev)) {
		/*
		 * Slave devices enumerated from ACPI namespace don't
		 * usually have chip_info but we still might want to use
		 * DMA with them.
		 */
		chip->enable_dma = drv_data->master_info->enable_dma;
	}

	chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
			(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);

	chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
	chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
				| SSITF_TxHiThresh(tx_hi_thres);

	/* set dma burst and threshold outside of chip_info path so that if
	 * chip_info goes away after setting chip->enable_dma, the
	 * burst and threshold can still respond to changes in bits_per_word */
	if (chip->enable_dma) {
		/* set up legal burst and threshold for dma */
		if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
						spi->bits_per_word,
						&chip->dma_burst_size,
						&chip->dma_threshold)) {
			dev_warn(&spi->dev, "in setup: DMA burst size reduced "
					"to match bits_per_word\n");
		}
	}

	clk_div = ssp_get_clk_div(drv_data, spi->max_speed_hz);
	chip->speed_hz = spi->max_speed_hz;

	chip->cr0 = clk_div
			| SSCR0_Motorola
			| SSCR0_DataSize(spi->bits_per_word > 16 ?
				spi->bits_per_word - 16 : spi->bits_per_word)
			| SSCR0_SSE
			| (spi->bits_per_word > 16 ? SSCR0_EDSS : 0);
	chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
	chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
			| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);

	if (spi->mode & SPI_LOOP)
		chip->cr1 |= SSCR1_LBM;

	/* NOTE:  PXA25x_SSP _could_ use external clocking ... */
	if (!pxa25x_ssp_comp(drv_data))
		dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
			drv_data->max_clk_rate
				/ (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)),
			chip->enable_dma ? "DMA" : "PIO");
	else
		dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
			drv_data->max_clk_rate / 2
				/ (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)),
			chip->enable_dma ? "DMA" : "PIO");

	if (spi->bits_per_word <= 8) {
		chip->n_bytes = 1;
		chip->read = u8_reader;
		chip->write = u8_writer;
	} else if (spi->bits_per_word <= 16) {
		chip->n_bytes = 2;
		chip->read = u16_reader;
		chip->write = u16_writer;
	} else if (spi->bits_per_word <= 32) {
		chip->cr0 |= SSCR0_EDSS;
		chip->n_bytes = 4;
		chip->read = u32_reader;
		chip->write = u32_writer;
	} else {
		dev_err(&spi->dev, "invalid wordsize\n");
		return -ENODEV;
	}
	chip->bits_per_word = spi->bits_per_word;

	spi_set_ctldata(spi, chip);

	if (drv_data->ssp_type == CE4100_SSP)
		return 0;

	return setup_cs(spi, chip, chip_info);
}

static void cleanup(struct spi_device *spi)
{
	struct chip_data *chip = spi_get_ctldata(spi);
	struct driver_data *drv_data = spi_master_get_devdata(spi->master);

	if (!chip)
		return;

	if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs))
		gpio_free(chip->gpio_cs);

	kfree(chip);
}

#ifdef CONFIG_ACPI
static int pxa2xx_spi_acpi_add_dma(struct acpi_resource *res, void *data)
{
	struct pxa2xx_spi_master *pdata = data;

	if (res->type == ACPI_RESOURCE_TYPE_FIXED_DMA) {
		const struct acpi_resource_fixed_dma *dma;

		dma = &res->data.fixed_dma;
		if (pdata->tx_slave_id < 0) {
			pdata->tx_slave_id = dma->request_lines;
			pdata->tx_chan_id = dma->channels;
		} else if (pdata->rx_slave_id < 0) {
			pdata->rx_slave_id = dma->request_lines;
			pdata->rx_chan_id = dma->channels;
		}
	}

	/* Tell the ACPI core to skip this resource */
	return 1;
}

static struct pxa2xx_spi_master *
pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
{
	struct pxa2xx_spi_master *pdata;
	struct list_head resource_list;
	struct acpi_device *adev;
	struct ssp_device *ssp;
	struct resource *res;
	int devid;

	if (!ACPI_HANDLE(&pdev->dev) ||
	    acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
		return NULL;

	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata) {
		dev_err(&pdev->dev,
			"failed to allocate memory for platform data\n");
		return NULL;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return NULL;

	ssp = &pdata->ssp;

	ssp->phys_base = res->start;
	ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(ssp->mmio_base))
		return PTR_ERR(ssp->mmio_base);

	ssp->clk = devm_clk_get(&pdev->dev, NULL);
	ssp->irq = platform_get_irq(pdev, 0);
	ssp->type = LPSS_SSP;
	ssp->pdev = pdev;

	ssp->port_id = -1;
	if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
		ssp->port_id = devid;

	pdata->num_chipselect = 1;
	pdata->rx_slave_id = -1;
	pdata->tx_slave_id = -1;

	INIT_LIST_HEAD(&resource_list);
	acpi_dev_get_resources(adev, &resource_list, pxa2xx_spi_acpi_add_dma,
			       pdata);
	acpi_dev_free_resource_list(&resource_list);

	pdata->enable_dma = pdata->rx_slave_id >= 0 && pdata->tx_slave_id >= 0;

	return pdata;
}

static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
	{ "INT33C0", 0 },
	{ "INT33C1", 0 },
	{ },
};
MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
#else
static inline struct pxa2xx_spi_master *
pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
{
	return NULL;
}
#endif

static int pxa2xx_spi_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct pxa2xx_spi_master *platform_info;
	struct spi_master *master;
	struct driver_data *drv_data;
	struct ssp_device *ssp;
	int status;

	platform_info = dev_get_platdata(dev);
	if (!platform_info) {
		platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
		if (!platform_info) {
			dev_err(&pdev->dev, "missing platform data\n");
			return -ENODEV;
		}
	}

	ssp = pxa_ssp_request(pdev->id, pdev->name);
	if (!ssp)
		ssp = &platform_info->ssp;

	if (!ssp->mmio_base) {
		dev_err(&pdev->dev, "failed to get ssp\n");
		return -ENODEV;
	}

	/* Allocate master with space for drv_data and null dma buffer */
	master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
	if (!master) {
		dev_err(&pdev->dev, "cannot alloc spi_master\n");
		pxa_ssp_free(ssp);
		return -ENOMEM;
	}
	drv_data = spi_master_get_devdata(master);
	drv_data->master = master;
	drv_data->master_info = platform_info;
	drv_data->pdev = pdev;
	drv_data->ssp = ssp;

	master->dev.parent = &pdev->dev;
	master->dev.of_node = pdev->dev.of_node;
	/* the spi->mode bits understood by this driver: */
	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;

	master->bus_num = ssp->port_id;
	master->num_chipselect = platform_info->num_chipselect;
	master->dma_alignment = DMA_ALIGNMENT;
	master->cleanup = cleanup;
	master->setup = setup;
	master->transfer_one_message = pxa2xx_spi_transfer_one_message;
	master->prepare_transfer_hardware = pxa2xx_spi_prepare_transfer;
	master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;

	drv_data->ssp_type = ssp->type;
	drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT);

	drv_data->ioaddr = ssp->mmio_base;
	drv_data->ssdr_physical = ssp->phys_base + SSDR;
	if (pxa25x_ssp_comp(drv_data)) {
		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
		drv_data->dma_cr1 = 0;
		drv_data->clear_sr = SSSR_ROR;
		drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
	} else {
		drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
		drv_data->dma_cr1 = DEFAULT_DMA_CR1;
		drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
		drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
	}

	status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
			drv_data);
	if (status < 0) {
		dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
		goto out_error_master_alloc;
	}

	/* Setup DMA if requested */
	drv_data->tx_channel = -1;
	drv_data->rx_channel = -1;
	if (platform_info->enable_dma) {
		status = pxa2xx_spi_dma_setup(drv_data);
		if (status) {
			dev_warn(dev, "failed to setup DMA, using PIO\n");
			platform_info->enable_dma = false;
		}
	}

	/* Enable SOC clock */
	clk_prepare_enable(ssp->clk);

	drv_data->max_clk_rate = clk_get_rate(ssp->clk);

	/* Load default SSP configuration */
	write_SSCR0(0, drv_data->ioaddr);
	write_SSCR1(SSCR1_RxTresh(RX_THRESH_DFLT) |
				SSCR1_TxTresh(TX_THRESH_DFLT),
				drv_data->ioaddr);
	write_SSCR0(SSCR0_SCR(2)
			| SSCR0_Motorola
			| SSCR0_DataSize(8),
			drv_data->ioaddr);
	if (!pxa25x_ssp_comp(drv_data))
		write_SSTO(0, drv_data->ioaddr);
	write_SSPSP(0, drv_data->ioaddr);

	lpss_ssp_setup(drv_data);

	tasklet_init(&drv_data->pump_transfers, pump_transfers,
		     (unsigned long)drv_data);

	/* Register with the SPI framework */
	platform_set_drvdata(pdev, drv_data);
	status = spi_register_master(master);
	if (status != 0) {
		dev_err(&pdev->dev, "problem registering spi master\n");
		goto out_error_clock_enabled;
	}

	pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
	pm_runtime_use_autosuspend(&pdev->dev);
	pm_runtime_set_active(&pdev->dev);
	pm_runtime_enable(&pdev->dev);

	return status;

out_error_clock_enabled:
	clk_disable_unprepare(ssp->clk);
	pxa2xx_spi_dma_release(drv_data);
	free_irq(ssp->irq, drv_data);

out_error_master_alloc:
	spi_master_put(master);
	pxa_ssp_free(ssp);
	return status;
}

static int pxa2xx_spi_remove(struct platform_device *pdev)
{
	struct driver_data *drv_data = platform_get_drvdata(pdev);
	struct ssp_device *ssp;

	if (!drv_data)
		return 0;
	ssp = drv_data->ssp;

	pm_runtime_get_sync(&pdev->dev);

	/* Disable the SSP at the peripheral and SOC level */
	write_SSCR0(0, drv_data->ioaddr);
	clk_disable_unprepare(ssp->clk);

	/* Release DMA */
	if (drv_data->master_info->enable_dma)
		pxa2xx_spi_dma_release(drv_data);

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

	/* Release IRQ */
	free_irq(ssp->irq, drv_data);

	/* Release SSP */
	pxa_ssp_free(ssp);

	/* Disconnect from the SPI framework */
	spi_unregister_master(drv_data->master);

	/* Prevent double remove */
	platform_set_drvdata(pdev, NULL);

	return 0;
}

static void pxa2xx_spi_shutdown(struct platform_device *pdev)
{
	int status = 0;

	if ((status = pxa2xx_spi_remove(pdev)) != 0)
		dev_err(&pdev->dev, "shutdown failed with %d\n", status);
}

#ifdef CONFIG_PM
static int pxa2xx_spi_suspend(struct device *dev)
{
	struct driver_data *drv_data = dev_get_drvdata(dev);
	struct ssp_device *ssp = drv_data->ssp;
	int status = 0;

	status = spi_master_suspend(drv_data->master);
	if (status != 0)
		return status;
	write_SSCR0(0, drv_data->ioaddr);

	if (!pm_runtime_suspended(dev))
		clk_disable_unprepare(ssp->clk);

	return 0;
}

static int pxa2xx_spi_resume(struct device *dev)
{
	struct driver_data *drv_data = dev_get_drvdata(dev);
	struct ssp_device *ssp = drv_data->ssp;
	int status = 0;

	pxa2xx_spi_dma_resume(drv_data);

	/* Enable the SSP clock */
	if (!pm_runtime_suspended(dev))
		clk_prepare_enable(ssp->clk);

	/* Start the queue running */
	status = spi_master_resume(drv_data->master);
	if (status != 0) {
		dev_err(dev, "problem starting queue (%d)\n", status);
		return status;
	}

	return 0;
}
#endif

#ifdef CONFIG_PM_RUNTIME
static int pxa2xx_spi_runtime_suspend(struct device *dev)
{
	struct driver_data *drv_data = dev_get_drvdata(dev);

	clk_disable_unprepare(drv_data->ssp->clk);
	return 0;
}

static int pxa2xx_spi_runtime_resume(struct device *dev)
{
	struct driver_data *drv_data = dev_get_drvdata(dev);

	clk_prepare_enable(drv_data->ssp->clk);
	return 0;
}
#endif

static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
	SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
			   pxa2xx_spi_runtime_resume, NULL)
};

static struct platform_driver driver = {
	.driver = {
		.name	= "pxa2xx-spi",
		.owner	= THIS_MODULE,
		.pm	= &pxa2xx_spi_pm_ops,
		.acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
	},
	.probe = pxa2xx_spi_probe,
	.remove = pxa2xx_spi_remove,
	.shutdown = pxa2xx_spi_shutdown,
};

static int __init pxa2xx_spi_init(void)
{
	return platform_driver_register(&driver);
}
subsys_initcall(pxa2xx_spi_init);

static void __exit pxa2xx_spi_exit(void)
{
	platform_driver_unregister(&driver);
}
module_exit(pxa2xx_spi_exit);