summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/radeon/radeon_i2c.c
blob: 545e31e6cc3a9bea64de147e14dc6fc6f138e1e8 (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
/*
 * Copyright 2007-8 Advanced Micro Devices, Inc.
 * Copyright 2008 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Dave Airlie
 *          Alex Deucher
 */

#include <linux/export.h>
#include <linux/pci.h>

#include <drm/drm_device.h>
#include <drm/drm_edid.h>
#include <drm/radeon_drm.h>

#include "radeon.h"
#include "atom.h"

extern int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
				   struct i2c_msg *msgs, int num);
extern u32 radeon_atom_hw_i2c_func(struct i2c_adapter *adap);

/**
 * radeon_ddc_probe
 *
 */
bool radeon_ddc_probe(struct radeon_connector *radeon_connector, bool use_aux)
{
	u8 out = 0x0;
	u8 buf[8];
	int ret;
	struct i2c_msg msgs[] = {
		{
			.addr = DDC_ADDR,
			.flags = 0,
			.len = 1,
			.buf = &out,
		},
		{
			.addr = DDC_ADDR,
			.flags = I2C_M_RD,
			.len = 8,
			.buf = buf,
		}
	};

	/* on hw with routers, select right port */
	if (radeon_connector->router.ddc_valid)
		radeon_router_select_ddc_port(radeon_connector);

	if (use_aux) {
		ret = i2c_transfer(&radeon_connector->ddc_bus->aux.ddc, msgs, 2);
	} else {
		ret = i2c_transfer(&radeon_connector->ddc_bus->adapter, msgs, 2);
	}

	if (ret != 2)
		/* Couldn't find an accessible DDC on this connector */
		return false;
	/* Probe also for valid EDID header
	 * EDID header starts with:
	 * 0x00,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00.
	 * Only the first 6 bytes must be valid as
	 * drm_edid_block_valid() can fix the last 2 bytes */
	if (drm_edid_header_is_valid(buf) < 6) {
		/* Couldn't find an accessible EDID on this
		 * connector */
		return false;
	}
	return true;
}

/* bit banging i2c */

static int pre_xfer(struct i2c_adapter *i2c_adap)
{
	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	uint32_t temp;

	mutex_lock(&i2c->mutex);

	/* RV410 appears to have a bug where the hw i2c in reset
	 * holds the i2c port in a bad state - switch hw i2c away before
	 * doing DDC - do this for all r200s/r300s/r400s for safety sake
	 */
	if (rec->hw_capable) {
		if ((rdev->family >= CHIP_R200) && !ASIC_IS_AVIVO(rdev)) {
			u32 reg;

			if (rdev->family >= CHIP_RV350)
				reg = RADEON_GPIO_MONID;
			else if ((rdev->family == CHIP_R300) ||
				 (rdev->family == CHIP_R350))
				reg = RADEON_GPIO_DVI_DDC;
			else
				reg = RADEON_GPIO_CRT2_DDC;

			mutex_lock(&rdev->dc_hw_i2c_mutex);
			if (rec->a_clk_reg == reg) {
				WREG32(RADEON_DVI_I2C_CNTL_0, (RADEON_I2C_SOFT_RST |
							       R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1)));
			} else {
				WREG32(RADEON_DVI_I2C_CNTL_0, (RADEON_I2C_SOFT_RST |
							       R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3)));
			}
			mutex_unlock(&rdev->dc_hw_i2c_mutex);
		}
	}

	/* switch the pads to ddc mode */
	if (ASIC_IS_DCE3(rdev) && rec->hw_capable) {
		temp = RREG32(rec->mask_clk_reg);
		temp &= ~(1 << 16);
		WREG32(rec->mask_clk_reg, temp);
	}

	/* clear the output pin values */
	temp = RREG32(rec->a_clk_reg) & ~rec->a_clk_mask;
	WREG32(rec->a_clk_reg, temp);

	temp = RREG32(rec->a_data_reg) & ~rec->a_data_mask;
	WREG32(rec->a_data_reg, temp);

	/* set the pins to input */
	temp = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
	WREG32(rec->en_clk_reg, temp);

	temp = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
	WREG32(rec->en_data_reg, temp);

	/* mask the gpio pins for software use */
	temp = RREG32(rec->mask_clk_reg) | rec->mask_clk_mask;
	WREG32(rec->mask_clk_reg, temp);
	temp = RREG32(rec->mask_clk_reg);

	temp = RREG32(rec->mask_data_reg) | rec->mask_data_mask;
	WREG32(rec->mask_data_reg, temp);
	temp = RREG32(rec->mask_data_reg);

	return 0;
}

static void post_xfer(struct i2c_adapter *i2c_adap)
{
	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	uint32_t temp;

	/* unmask the gpio pins for software use */
	temp = RREG32(rec->mask_clk_reg) & ~rec->mask_clk_mask;
	WREG32(rec->mask_clk_reg, temp);
	temp = RREG32(rec->mask_clk_reg);

	temp = RREG32(rec->mask_data_reg) & ~rec->mask_data_mask;
	WREG32(rec->mask_data_reg, temp);
	temp = RREG32(rec->mask_data_reg);

	mutex_unlock(&i2c->mutex);
}

static int get_clock(void *i2c_priv)
{
	struct radeon_i2c_chan *i2c = i2c_priv;
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	uint32_t val;

	/* read the value off the pin */
	val = RREG32(rec->y_clk_reg);
	val &= rec->y_clk_mask;

	return (val != 0);
}


static int get_data(void *i2c_priv)
{
	struct radeon_i2c_chan *i2c = i2c_priv;
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	uint32_t val;

	/* read the value off the pin */
	val = RREG32(rec->y_data_reg);
	val &= rec->y_data_mask;

	return (val != 0);
}

static void set_clock(void *i2c_priv, int clock)
{
	struct radeon_i2c_chan *i2c = i2c_priv;
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	uint32_t val;

	/* set pin direction */
	val = RREG32(rec->en_clk_reg) & ~rec->en_clk_mask;
	val |= clock ? 0 : rec->en_clk_mask;
	WREG32(rec->en_clk_reg, val);
}

static void set_data(void *i2c_priv, int data)
{
	struct radeon_i2c_chan *i2c = i2c_priv;
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	uint32_t val;

	/* set pin direction */
	val = RREG32(rec->en_data_reg) & ~rec->en_data_mask;
	val |= data ? 0 : rec->en_data_mask;
	WREG32(rec->en_data_reg, val);
}

/* hw i2c */

static u32 radeon_get_i2c_prescale(struct radeon_device *rdev)
{
	u32 sclk = rdev->pm.current_sclk;
	u32 prescale = 0;
	u32 nm;
	u8 n, m, loop;
	int i2c_clock;

	switch (rdev->family) {
	case CHIP_R100:
	case CHIP_RV100:
	case CHIP_RS100:
	case CHIP_RV200:
	case CHIP_RS200:
	case CHIP_R200:
	case CHIP_RV250:
	case CHIP_RS300:
	case CHIP_RV280:
	case CHIP_R300:
	case CHIP_R350:
	case CHIP_RV350:
		i2c_clock = 60;
		nm = (sclk * 10) / (i2c_clock * 4);
		for (loop = 1; loop < 255; loop++) {
			if ((nm / loop) < loop)
				break;
		}
		n = loop - 1;
		m = loop - 2;
		prescale = m | (n << 8);
		break;
	case CHIP_RV380:
	case CHIP_RS400:
	case CHIP_RS480:
	case CHIP_R420:
	case CHIP_R423:
	case CHIP_RV410:
		prescale = (((sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
		break;
	case CHIP_RS600:
	case CHIP_RS690:
	case CHIP_RS740:
		/* todo */
		break;
	case CHIP_RV515:
	case CHIP_R520:
	case CHIP_RV530:
	case CHIP_RV560:
	case CHIP_RV570:
	case CHIP_R580:
		i2c_clock = 50;
		if (rdev->family == CHIP_R520)
			prescale = (127 << 8) + ((sclk * 10) / (4 * 127 * i2c_clock));
		else
			prescale = (((sclk * 10)/(4 * 128 * 100) + 1) << 8) + 128;
		break;
	case CHIP_R600:
	case CHIP_RV610:
	case CHIP_RV630:
	case CHIP_RV670:
		/* todo */
		break;
	case CHIP_RV620:
	case CHIP_RV635:
	case CHIP_RS780:
	case CHIP_RS880:
	case CHIP_RV770:
	case CHIP_RV730:
	case CHIP_RV710:
	case CHIP_RV740:
		/* todo */
		break;
	case CHIP_CEDAR:
	case CHIP_REDWOOD:
	case CHIP_JUNIPER:
	case CHIP_CYPRESS:
	case CHIP_HEMLOCK:
		/* todo */
		break;
	default:
		DRM_ERROR("i2c: unhandled radeon chip\n");
		break;
	}
	return prescale;
}


/* hw i2c engine for r1xx-4xx hardware
 * hw can buffer up to 15 bytes
 */
static int r100_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
			    struct i2c_msg *msgs, int num)
{
	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	struct i2c_msg *p;
	int i, j, k, ret = num;
	u32 prescale;
	u32 i2c_cntl_0, i2c_cntl_1, i2c_data;
	u32 tmp, reg;

	mutex_lock(&rdev->dc_hw_i2c_mutex);
	/* take the pm lock since we need a constant sclk */
	mutex_lock(&rdev->pm.mutex);

	prescale = radeon_get_i2c_prescale(rdev);

	reg = ((prescale << RADEON_I2C_PRESCALE_SHIFT) |
	       RADEON_I2C_DRIVE_EN |
	       RADEON_I2C_START |
	       RADEON_I2C_STOP |
	       RADEON_I2C_GO);

	if (rdev->is_atom_bios) {
		tmp = RREG32(RADEON_BIOS_6_SCRATCH);
		WREG32(RADEON_BIOS_6_SCRATCH, tmp | ATOM_S6_HW_I2C_BUSY_STATE);
	}

	if (rec->mm_i2c) {
		i2c_cntl_0 = RADEON_I2C_CNTL_0;
		i2c_cntl_1 = RADEON_I2C_CNTL_1;
		i2c_data = RADEON_I2C_DATA;
	} else {
		i2c_cntl_0 = RADEON_DVI_I2C_CNTL_0;
		i2c_cntl_1 = RADEON_DVI_I2C_CNTL_1;
		i2c_data = RADEON_DVI_I2C_DATA;

		switch (rdev->family) {
		case CHIP_R100:
		case CHIP_RV100:
		case CHIP_RS100:
		case CHIP_RV200:
		case CHIP_RS200:
		case CHIP_RS300:
			switch (rec->mask_clk_reg) {
			case RADEON_GPIO_DVI_DDC:
				/* no gpio select bit */
				break;
			default:
				DRM_ERROR("gpio not supported with hw i2c\n");
				ret = -EINVAL;
				goto done;
			}
			break;
		case CHIP_R200:
			/* only bit 4 on r200 */
			switch (rec->mask_clk_reg) {
			case RADEON_GPIO_DVI_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
				break;
			case RADEON_GPIO_MONID:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
				break;
			default:
				DRM_ERROR("gpio not supported with hw i2c\n");
				ret = -EINVAL;
				goto done;
			}
			break;
		case CHIP_RV250:
		case CHIP_RV280:
			/* bits 3 and 4 */
			switch (rec->mask_clk_reg) {
			case RADEON_GPIO_DVI_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
				break;
			case RADEON_GPIO_VGA_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC2);
				break;
			case RADEON_GPIO_CRT2_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
				break;
			default:
				DRM_ERROR("gpio not supported with hw i2c\n");
				ret = -EINVAL;
				goto done;
			}
			break;
		case CHIP_R300:
		case CHIP_R350:
			/* only bit 4 on r300/r350 */
			switch (rec->mask_clk_reg) {
			case RADEON_GPIO_VGA_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
				break;
			case RADEON_GPIO_DVI_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
				break;
			default:
				DRM_ERROR("gpio not supported with hw i2c\n");
				ret = -EINVAL;
				goto done;
			}
			break;
		case CHIP_RV350:
		case CHIP_RV380:
		case CHIP_R420:
		case CHIP_R423:
		case CHIP_RV410:
		case CHIP_RS400:
		case CHIP_RS480:
			/* bits 3 and 4 */
			switch (rec->mask_clk_reg) {
			case RADEON_GPIO_VGA_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC1);
				break;
			case RADEON_GPIO_DVI_DDC:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC2);
				break;
			case RADEON_GPIO_MONID:
				reg |= R200_DVI_I2C_PIN_SEL(R200_SEL_DDC3);
				break;
			default:
				DRM_ERROR("gpio not supported with hw i2c\n");
				ret = -EINVAL;
				goto done;
			}
			break;
		default:
			DRM_ERROR("unsupported asic\n");
			ret = -EINVAL;
			goto done;
			break;
		}
	}

	/* check for bus probe */
	p = &msgs[0];
	if ((num == 1) && (p->len == 0)) {
		WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
				    RADEON_I2C_NACK |
				    RADEON_I2C_HALT |
				    RADEON_I2C_SOFT_RST));
		WREG32(i2c_data, (p->addr << 1) & 0xff);
		WREG32(i2c_data, 0);
		WREG32(i2c_cntl_1, ((1 << RADEON_I2C_DATA_COUNT_SHIFT) |
				    (1 << RADEON_I2C_ADDR_COUNT_SHIFT) |
				    RADEON_I2C_EN |
				    (48 << RADEON_I2C_TIME_LIMIT_SHIFT)));
		WREG32(i2c_cntl_0, reg);
		for (k = 0; k < 32; k++) {
			udelay(10);
			tmp = RREG32(i2c_cntl_0);
			if (tmp & RADEON_I2C_GO)
				continue;
			tmp = RREG32(i2c_cntl_0);
			if (tmp & RADEON_I2C_DONE)
				break;
			else {
				DRM_DEBUG("i2c write error 0x%08x\n", tmp);
				WREG32(i2c_cntl_0, tmp | RADEON_I2C_ABORT);
				ret = -EIO;
				goto done;
			}
		}
		goto done;
	}

	for (i = 0; i < num; i++) {
		p = &msgs[i];
		for (j = 0; j < p->len; j++) {
			if (p->flags & I2C_M_RD) {
				WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
						    RADEON_I2C_NACK |
						    RADEON_I2C_HALT |
						    RADEON_I2C_SOFT_RST));
				WREG32(i2c_data, ((p->addr << 1) & 0xff) | 0x1);
				WREG32(i2c_cntl_1, ((1 << RADEON_I2C_DATA_COUNT_SHIFT) |
						    (1 << RADEON_I2C_ADDR_COUNT_SHIFT) |
						    RADEON_I2C_EN |
						    (48 << RADEON_I2C_TIME_LIMIT_SHIFT)));
				WREG32(i2c_cntl_0, reg | RADEON_I2C_RECEIVE);
				for (k = 0; k < 32; k++) {
					udelay(10);
					tmp = RREG32(i2c_cntl_0);
					if (tmp & RADEON_I2C_GO)
						continue;
					tmp = RREG32(i2c_cntl_0);
					if (tmp & RADEON_I2C_DONE)
						break;
					else {
						DRM_DEBUG("i2c read error 0x%08x\n", tmp);
						WREG32(i2c_cntl_0, tmp | RADEON_I2C_ABORT);
						ret = -EIO;
						goto done;
					}
				}
				p->buf[j] = RREG32(i2c_data) & 0xff;
			} else {
				WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
						    RADEON_I2C_NACK |
						    RADEON_I2C_HALT |
						    RADEON_I2C_SOFT_RST));
				WREG32(i2c_data, (p->addr << 1) & 0xff);
				WREG32(i2c_data, p->buf[j]);
				WREG32(i2c_cntl_1, ((1 << RADEON_I2C_DATA_COUNT_SHIFT) |
						    (1 << RADEON_I2C_ADDR_COUNT_SHIFT) |
						    RADEON_I2C_EN |
						    (48 << RADEON_I2C_TIME_LIMIT_SHIFT)));
				WREG32(i2c_cntl_0, reg);
				for (k = 0; k < 32; k++) {
					udelay(10);
					tmp = RREG32(i2c_cntl_0);
					if (tmp & RADEON_I2C_GO)
						continue;
					tmp = RREG32(i2c_cntl_0);
					if (tmp & RADEON_I2C_DONE)
						break;
					else {
						DRM_DEBUG("i2c write error 0x%08x\n", tmp);
						WREG32(i2c_cntl_0, tmp | RADEON_I2C_ABORT);
						ret = -EIO;
						goto done;
					}
				}
			}
		}
	}

done:
	WREG32(i2c_cntl_0, 0);
	WREG32(i2c_cntl_1, 0);
	WREG32(i2c_cntl_0, (RADEON_I2C_DONE |
			    RADEON_I2C_NACK |
			    RADEON_I2C_HALT |
			    RADEON_I2C_SOFT_RST));

	if (rdev->is_atom_bios) {
		tmp = RREG32(RADEON_BIOS_6_SCRATCH);
		tmp &= ~ATOM_S6_HW_I2C_BUSY_STATE;
		WREG32(RADEON_BIOS_6_SCRATCH, tmp);
	}

	mutex_unlock(&rdev->pm.mutex);
	mutex_unlock(&rdev->dc_hw_i2c_mutex);

	return ret;
}

/* hw i2c engine for r5xx hardware
 * hw can buffer up to 15 bytes
 */
static int r500_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
			    struct i2c_msg *msgs, int num)
{
	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	struct i2c_msg *p;
	int i, j, remaining, current_count, buffer_offset, ret = num;
	u32 prescale;
	u32 tmp, reg;
	u32 saved1, saved2;

	mutex_lock(&rdev->dc_hw_i2c_mutex);
	/* take the pm lock since we need a constant sclk */
	mutex_lock(&rdev->pm.mutex);

	prescale = radeon_get_i2c_prescale(rdev);

	/* clear gpio mask bits */
	tmp = RREG32(rec->mask_clk_reg);
	tmp &= ~rec->mask_clk_mask;
	WREG32(rec->mask_clk_reg, tmp);
	tmp = RREG32(rec->mask_clk_reg);

	tmp = RREG32(rec->mask_data_reg);
	tmp &= ~rec->mask_data_mask;
	WREG32(rec->mask_data_reg, tmp);
	tmp = RREG32(rec->mask_data_reg);

	/* clear pin values */
	tmp = RREG32(rec->a_clk_reg);
	tmp &= ~rec->a_clk_mask;
	WREG32(rec->a_clk_reg, tmp);
	tmp = RREG32(rec->a_clk_reg);

	tmp = RREG32(rec->a_data_reg);
	tmp &= ~rec->a_data_mask;
	WREG32(rec->a_data_reg, tmp);
	tmp = RREG32(rec->a_data_reg);

	/* set the pins to input */
	tmp = RREG32(rec->en_clk_reg);
	tmp &= ~rec->en_clk_mask;
	WREG32(rec->en_clk_reg, tmp);
	tmp = RREG32(rec->en_clk_reg);

	tmp = RREG32(rec->en_data_reg);
	tmp &= ~rec->en_data_mask;
	WREG32(rec->en_data_reg, tmp);
	tmp = RREG32(rec->en_data_reg);

	/* */
	tmp = RREG32(RADEON_BIOS_6_SCRATCH);
	WREG32(RADEON_BIOS_6_SCRATCH, tmp | ATOM_S6_HW_I2C_BUSY_STATE);
	saved1 = RREG32(AVIVO_DC_I2C_CONTROL1);
	saved2 = RREG32(0x494);
	WREG32(0x494, saved2 | 0x1);

	WREG32(AVIVO_DC_I2C_ARBITRATION, AVIVO_DC_I2C_SW_WANTS_TO_USE_I2C);
	for (i = 0; i < 50; i++) {
		udelay(1);
		if (RREG32(AVIVO_DC_I2C_ARBITRATION) & AVIVO_DC_I2C_SW_CAN_USE_I2C)
			break;
	}
	if (i == 50) {
		DRM_ERROR("failed to get i2c bus\n");
		ret = -EBUSY;
		goto done;
	}

	reg = AVIVO_DC_I2C_START | AVIVO_DC_I2C_STOP | AVIVO_DC_I2C_EN;
	switch (rec->mask_clk_reg) {
	case AVIVO_DC_GPIO_DDC1_MASK:
		reg |= AVIVO_DC_I2C_PIN_SELECT(AVIVO_SEL_DDC1);
		break;
	case AVIVO_DC_GPIO_DDC2_MASK:
		reg |= AVIVO_DC_I2C_PIN_SELECT(AVIVO_SEL_DDC2);
		break;
	case AVIVO_DC_GPIO_DDC3_MASK:
		reg |= AVIVO_DC_I2C_PIN_SELECT(AVIVO_SEL_DDC3);
		break;
	default:
		DRM_ERROR("gpio not supported with hw i2c\n");
		ret = -EINVAL;
		goto done;
	}

	/* check for bus probe */
	p = &msgs[0];
	if ((num == 1) && (p->len == 0)) {
		WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
					      AVIVO_DC_I2C_NACK |
					      AVIVO_DC_I2C_HALT));
		WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
		udelay(1);
		WREG32(AVIVO_DC_I2C_RESET, 0);

		WREG32(AVIVO_DC_I2C_DATA, (p->addr << 1) & 0xff);
		WREG32(AVIVO_DC_I2C_DATA, 0);

		WREG32(AVIVO_DC_I2C_CONTROL3, AVIVO_DC_I2C_TIME_LIMIT(48));
		WREG32(AVIVO_DC_I2C_CONTROL2, (AVIVO_DC_I2C_ADDR_COUNT(1) |
					       AVIVO_DC_I2C_DATA_COUNT(1) |
					       (prescale << 16)));
		WREG32(AVIVO_DC_I2C_CONTROL1, reg);
		WREG32(AVIVO_DC_I2C_STATUS1, AVIVO_DC_I2C_GO);
		for (j = 0; j < 200; j++) {
			udelay(50);
			tmp = RREG32(AVIVO_DC_I2C_STATUS1);
			if (tmp & AVIVO_DC_I2C_GO)
				continue;
			tmp = RREG32(AVIVO_DC_I2C_STATUS1);
			if (tmp & AVIVO_DC_I2C_DONE)
				break;
			else {
				DRM_DEBUG("i2c write error 0x%08x\n", tmp);
				WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_ABORT);
				ret = -EIO;
				goto done;
			}
		}
		goto done;
	}

	for (i = 0; i < num; i++) {
		p = &msgs[i];
		remaining = p->len;
		buffer_offset = 0;
		if (p->flags & I2C_M_RD) {
			while (remaining) {
				if (remaining > 15)
					current_count = 15;
				else
					current_count = remaining;
				WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
							      AVIVO_DC_I2C_NACK |
							      AVIVO_DC_I2C_HALT));
				WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
				udelay(1);
				WREG32(AVIVO_DC_I2C_RESET, 0);

				WREG32(AVIVO_DC_I2C_DATA, ((p->addr << 1) & 0xff) | 0x1);
				WREG32(AVIVO_DC_I2C_CONTROL3, AVIVO_DC_I2C_TIME_LIMIT(48));
				WREG32(AVIVO_DC_I2C_CONTROL2, (AVIVO_DC_I2C_ADDR_COUNT(1) |
							       AVIVO_DC_I2C_DATA_COUNT(current_count) |
							       (prescale << 16)));
				WREG32(AVIVO_DC_I2C_CONTROL1, reg | AVIVO_DC_I2C_RECEIVE);
				WREG32(AVIVO_DC_I2C_STATUS1, AVIVO_DC_I2C_GO);
				for (j = 0; j < 200; j++) {
					udelay(50);
					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
					if (tmp & AVIVO_DC_I2C_GO)
						continue;
					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
					if (tmp & AVIVO_DC_I2C_DONE)
						break;
					else {
						DRM_DEBUG("i2c read error 0x%08x\n", tmp);
						WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_ABORT);
						ret = -EIO;
						goto done;
					}
				}
				for (j = 0; j < current_count; j++)
					p->buf[buffer_offset + j] = RREG32(AVIVO_DC_I2C_DATA) & 0xff;
				remaining -= current_count;
				buffer_offset += current_count;
			}
		} else {
			while (remaining) {
				if (remaining > 15)
					current_count = 15;
				else
					current_count = remaining;
				WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
							      AVIVO_DC_I2C_NACK |
							      AVIVO_DC_I2C_HALT));
				WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
				udelay(1);
				WREG32(AVIVO_DC_I2C_RESET, 0);

				WREG32(AVIVO_DC_I2C_DATA, (p->addr << 1) & 0xff);
				for (j = 0; j < current_count; j++)
					WREG32(AVIVO_DC_I2C_DATA, p->buf[buffer_offset + j]);

				WREG32(AVIVO_DC_I2C_CONTROL3, AVIVO_DC_I2C_TIME_LIMIT(48));
				WREG32(AVIVO_DC_I2C_CONTROL2, (AVIVO_DC_I2C_ADDR_COUNT(1) |
							       AVIVO_DC_I2C_DATA_COUNT(current_count) |
							       (prescale << 16)));
				WREG32(AVIVO_DC_I2C_CONTROL1, reg);
				WREG32(AVIVO_DC_I2C_STATUS1, AVIVO_DC_I2C_GO);
				for (j = 0; j < 200; j++) {
					udelay(50);
					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
					if (tmp & AVIVO_DC_I2C_GO)
						continue;
					tmp = RREG32(AVIVO_DC_I2C_STATUS1);
					if (tmp & AVIVO_DC_I2C_DONE)
						break;
					else {
						DRM_DEBUG("i2c write error 0x%08x\n", tmp);
						WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_ABORT);
						ret = -EIO;
						goto done;
					}
				}
				remaining -= current_count;
				buffer_offset += current_count;
			}
		}
	}

done:
	WREG32(AVIVO_DC_I2C_STATUS1, (AVIVO_DC_I2C_DONE |
				      AVIVO_DC_I2C_NACK |
				      AVIVO_DC_I2C_HALT));
	WREG32(AVIVO_DC_I2C_RESET, AVIVO_DC_I2C_SOFT_RESET);
	udelay(1);
	WREG32(AVIVO_DC_I2C_RESET, 0);

	WREG32(AVIVO_DC_I2C_ARBITRATION, AVIVO_DC_I2C_SW_DONE_USING_I2C);
	WREG32(AVIVO_DC_I2C_CONTROL1, saved1);
	WREG32(0x494, saved2);
	tmp = RREG32(RADEON_BIOS_6_SCRATCH);
	tmp &= ~ATOM_S6_HW_I2C_BUSY_STATE;
	WREG32(RADEON_BIOS_6_SCRATCH, tmp);

	mutex_unlock(&rdev->pm.mutex);
	mutex_unlock(&rdev->dc_hw_i2c_mutex);

	return ret;
}

static int radeon_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
			      struct i2c_msg *msgs, int num)
{
	struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
	struct radeon_device *rdev = i2c->dev->dev_private;
	struct radeon_i2c_bus_rec *rec = &i2c->rec;
	int ret = 0;

	mutex_lock(&i2c->mutex);

	switch (rdev->family) {
	case CHIP_R100:
	case CHIP_RV100:
	case CHIP_RS100:
	case CHIP_RV200:
	case CHIP_RS200:
	case CHIP_R200:
	case CHIP_RV250:
	case CHIP_RS300:
	case CHIP_RV280:
	case CHIP_R300:
	case CHIP_R350:
	case CHIP_RV350:
	case CHIP_RV380:
	case CHIP_R420:
	case CHIP_R423:
	case CHIP_RV410:
	case CHIP_RS400:
	case CHIP_RS480:
		ret = r100_hw_i2c_xfer(i2c_adap, msgs, num);
		break;
	case CHIP_RS600:
	case CHIP_RS690:
	case CHIP_RS740:
		/* XXX fill in hw i2c implementation */
		break;
	case CHIP_RV515:
	case CHIP_R520:
	case CHIP_RV530:
	case CHIP_RV560:
	case CHIP_RV570:
	case CHIP_R580:
		if (rec->mm_i2c)
			ret = r100_hw_i2c_xfer(i2c_adap, msgs, num);
		else
			ret = r500_hw_i2c_xfer(i2c_adap, msgs, num);
		break;
	case CHIP_R600:
	case CHIP_RV610:
	case CHIP_RV630:
	case CHIP_RV670:
		/* XXX fill in hw i2c implementation */
		break;
	case CHIP_RV620:
	case CHIP_RV635:
	case CHIP_RS780:
	case CHIP_RS880:
	case CHIP_RV770:
	case CHIP_RV730:
	case CHIP_RV710:
	case CHIP_RV740:
		/* XXX fill in hw i2c implementation */
		break;
	case CHIP_CEDAR:
	case CHIP_REDWOOD:
	case CHIP_JUNIPER:
	case CHIP_CYPRESS:
	case CHIP_HEMLOCK:
		/* XXX fill in hw i2c implementation */
		break;
	default:
		DRM_ERROR("i2c: unhandled radeon chip\n");
		ret = -EIO;
		break;
	}

	mutex_unlock(&i2c->mutex);

	return ret;
}

static u32 radeon_hw_i2c_func(struct i2c_adapter *adap)
{
	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}

static const struct i2c_algorithm radeon_i2c_algo = {
	.master_xfer = radeon_hw_i2c_xfer,
	.functionality = radeon_hw_i2c_func,
};

static const struct i2c_algorithm radeon_atom_i2c_algo = {
	.master_xfer = radeon_atom_hw_i2c_xfer,
	.functionality = radeon_atom_hw_i2c_func,
};

struct radeon_i2c_chan *radeon_i2c_create(struct drm_device *dev,
					  struct radeon_i2c_bus_rec *rec,
					  const char *name)
{
	struct radeon_device *rdev = dev->dev_private;
	struct radeon_i2c_chan *i2c;
	int ret;

	/* don't add the mm_i2c bus unless hw_i2c is enabled */
	if (rec->mm_i2c && (radeon_hw_i2c == 0))
		return NULL;

	i2c = kzalloc(sizeof(struct radeon_i2c_chan), GFP_KERNEL);
	if (i2c == NULL)
		return NULL;

	i2c->rec = *rec;
	i2c->adapter.owner = THIS_MODULE;
	i2c->adapter.class = I2C_CLASS_DDC;
	i2c->adapter.dev.parent = &dev->pdev->dev;
	i2c->dev = dev;
	i2c_set_adapdata(&i2c->adapter, i2c);
	mutex_init(&i2c->mutex);
	if (rec->mm_i2c ||
	    (rec->hw_capable &&
	     radeon_hw_i2c &&
	     ((rdev->family <= CHIP_RS480) ||
	      ((rdev->family >= CHIP_RV515) && (rdev->family <= CHIP_R580))))) {
		/* set the radeon hw i2c adapter */
		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
			 "Radeon i2c hw bus %s", name);
		i2c->adapter.algo = &radeon_i2c_algo;
		ret = i2c_add_adapter(&i2c->adapter);
		if (ret)
			goto out_free;
	} else if (rec->hw_capable &&
		   radeon_hw_i2c &&
		   ASIC_IS_DCE3(rdev)) {
		/* hw i2c using atom */
		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
			 "Radeon i2c hw bus %s", name);
		i2c->adapter.algo = &radeon_atom_i2c_algo;
		ret = i2c_add_adapter(&i2c->adapter);
		if (ret)
			goto out_free;
	} else {
		/* set the radeon bit adapter */
		snprintf(i2c->adapter.name, sizeof(i2c->adapter.name),
			 "Radeon i2c bit bus %s", name);
		i2c->adapter.algo_data = &i2c->bit;
		i2c->bit.pre_xfer = pre_xfer;
		i2c->bit.post_xfer = post_xfer;
		i2c->bit.setsda = set_data;
		i2c->bit.setscl = set_clock;
		i2c->bit.getsda = get_data;
		i2c->bit.getscl = get_clock;
		i2c->bit.udelay = 10;
		i2c->bit.timeout = usecs_to_jiffies(2200);	/* from VESA */
		i2c->bit.data = i2c;
		ret = i2c_bit_add_bus(&i2c->adapter);
		if (ret) {
			DRM_ERROR("Failed to register bit i2c %s\n", name);
			goto out_free;
		}
	}

	return i2c;
out_free:
	kfree(i2c);
	return NULL;

}

void radeon_i2c_destroy(struct radeon_i2c_chan *i2c)
{
	if (!i2c)
		return;
	WARN_ON(i2c->has_aux);
	i2c_del_adapter(&i2c->adapter);
	kfree(i2c);
}

/* Add the default buses */
void radeon_i2c_init(struct radeon_device *rdev)
{
	if (radeon_hw_i2c)
		DRM_INFO("hw_i2c forced on, you may experience display detection problems!\n");

	if (rdev->is_atom_bios)
		radeon_atombios_i2c_init(rdev);
	else
		radeon_combios_i2c_init(rdev);
}

/* remove all the buses */
void radeon_i2c_fini(struct radeon_device *rdev)
{
	int i;

	for (i = 0; i < RADEON_MAX_I2C_BUS; i++) {
		if (rdev->i2c_bus[i]) {
			radeon_i2c_destroy(rdev->i2c_bus[i]);
			rdev->i2c_bus[i] = NULL;
		}
	}
}

/* Add additional buses */
void radeon_i2c_add(struct radeon_device *rdev,
		    struct radeon_i2c_bus_rec *rec,
		    const char *name)
{
	struct drm_device *dev = rdev->ddev;
	int i;

	for (i = 0; i < RADEON_MAX_I2C_BUS; i++) {
		if (!rdev->i2c_bus[i]) {
			rdev->i2c_bus[i] = radeon_i2c_create(dev, rec, name);
			return;
		}
	}
}

/* looks up bus based on id */
struct radeon_i2c_chan *radeon_i2c_lookup(struct radeon_device *rdev,
					  struct radeon_i2c_bus_rec *i2c_bus)
{
	int i;

	for (i = 0; i < RADEON_MAX_I2C_BUS; i++) {
		if (rdev->i2c_bus[i] &&
		    (rdev->i2c_bus[i]->rec.i2c_id == i2c_bus->i2c_id)) {
			return rdev->i2c_bus[i];
		}
	}
	return NULL;
}

void radeon_i2c_get_byte(struct radeon_i2c_chan *i2c_bus,
			 u8 slave_addr,
			 u8 addr,
			 u8 *val)
{
	u8 out_buf[2];
	u8 in_buf[2];
	struct i2c_msg msgs[] = {
		{
			.addr = slave_addr,
			.flags = 0,
			.len = 1,
			.buf = out_buf,
		},
		{
			.addr = slave_addr,
			.flags = I2C_M_RD,
			.len = 1,
			.buf = in_buf,
		}
	};

	out_buf[0] = addr;
	out_buf[1] = 0;

	if (i2c_transfer(&i2c_bus->adapter, msgs, 2) == 2) {
		*val = in_buf[0];
		DRM_DEBUG("val = 0x%02x\n", *val);
	} else {
		DRM_DEBUG("i2c 0x%02x 0x%02x read failed\n",
			  addr, *val);
	}
}

void radeon_i2c_put_byte(struct radeon_i2c_chan *i2c_bus,
			 u8 slave_addr,
			 u8 addr,
			 u8 val)
{
	uint8_t out_buf[2];
	struct i2c_msg msg = {
		.addr = slave_addr,
		.flags = 0,
		.len = 2,
		.buf = out_buf,
	};

	out_buf[0] = addr;
	out_buf[1] = val;

	if (i2c_transfer(&i2c_bus->adapter, &msg, 1) != 1)
		DRM_DEBUG("i2c 0x%02x 0x%02x write failed\n",
			  addr, val);
}

/* ddc router switching */
void radeon_router_select_ddc_port(struct radeon_connector *radeon_connector)
{
	u8 val;

	if (!radeon_connector->router.ddc_valid)
		return;

	if (!radeon_connector->router_bus)
		return;

	radeon_i2c_get_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x3, &val);
	val &= ~radeon_connector->router.ddc_mux_control_pin;
	radeon_i2c_put_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x3, val);
	radeon_i2c_get_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x1, &val);
	val &= ~radeon_connector->router.ddc_mux_control_pin;
	val |= radeon_connector->router.ddc_mux_state;
	radeon_i2c_put_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x1, val);
}

/* clock/data router switching */
void radeon_router_select_cd_port(struct radeon_connector *radeon_connector)
{
	u8 val;

	if (!radeon_connector->router.cd_valid)
		return;

	if (!radeon_connector->router_bus)
		return;

	radeon_i2c_get_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x3, &val);
	val &= ~radeon_connector->router.cd_mux_control_pin;
	radeon_i2c_put_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x3, val);
	radeon_i2c_get_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x1, &val);
	val &= ~radeon_connector->router.cd_mux_control_pin;
	val |= radeon_connector->router.cd_mux_state;
	radeon_i2c_put_byte(radeon_connector->router_bus,
			    radeon_connector->router.i2c_addr,
			    0x1, val);
}