aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/video/fbdev/da8xx-fb.c
blob: 9ea817ac1d816f5957b79b977d2547787aa4d309 (plain) (blame)
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
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2008-2009 MontaVista Software Inc.
 * Copyright (C) 2008-2009 Texas Instruments Inc
 *
 * Based on the LCD driver for TI Avalanche processors written by
 * Ajay Singh and Shalom Hai.
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fb.h>
#include <linux/dma-mapping.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/uaccess.h>
#include <linux/pm_runtime.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/console.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/lcm.h>
#include <video/da8xx-fb.h>
#include <asm/div64.h>

#define DRIVER_NAME "da8xx_lcdc"

#define LCD_VERSION_1	1
#define LCD_VERSION_2	2

/* LCD Status Register */
#define LCD_END_OF_FRAME1		BIT(9)
#define LCD_END_OF_FRAME0		BIT(8)
#define LCD_PL_LOAD_DONE		BIT(6)
#define LCD_FIFO_UNDERFLOW		BIT(5)
#define LCD_SYNC_LOST			BIT(2)
#define LCD_FRAME_DONE			BIT(0)

/* LCD DMA Control Register */
#define LCD_DMA_BURST_SIZE(x)		((x) << 4)
#define LCD_DMA_BURST_1			0x0
#define LCD_DMA_BURST_2			0x1
#define LCD_DMA_BURST_4			0x2
#define LCD_DMA_BURST_8			0x3
#define LCD_DMA_BURST_16		0x4
#define LCD_V1_END_OF_FRAME_INT_ENA	BIT(2)
#define LCD_V2_END_OF_FRAME0_INT_ENA	BIT(8)
#define LCD_V2_END_OF_FRAME1_INT_ENA	BIT(9)
#define LCD_DUAL_FRAME_BUFFER_ENABLE	BIT(0)

/* LCD Control Register */
#define LCD_CLK_DIVISOR(x)		((x) << 8)
#define LCD_RASTER_MODE			0x01

/* LCD Raster Control Register */
#define LCD_PALETTE_LOAD_MODE(x)	((x) << 20)
#define PALETTE_AND_DATA		0x00
#define PALETTE_ONLY			0x01
#define DATA_ONLY			0x02

#define LCD_MONO_8BIT_MODE		BIT(9)
#define LCD_RASTER_ORDER		BIT(8)
#define LCD_TFT_MODE			BIT(7)
#define LCD_V1_UNDERFLOW_INT_ENA	BIT(6)
#define LCD_V2_UNDERFLOW_INT_ENA	BIT(5)
#define LCD_V1_PL_INT_ENA		BIT(4)
#define LCD_V2_PL_INT_ENA		BIT(6)
#define LCD_MONOCHROME_MODE		BIT(1)
#define LCD_RASTER_ENABLE		BIT(0)
#define LCD_TFT_ALT_ENABLE		BIT(23)
#define LCD_STN_565_ENABLE		BIT(24)
#define LCD_V2_DMA_CLK_EN		BIT(2)
#define LCD_V2_LIDD_CLK_EN		BIT(1)
#define LCD_V2_CORE_CLK_EN		BIT(0)
#define LCD_V2_LPP_B10			26
#define LCD_V2_TFT_24BPP_MODE		BIT(25)
#define LCD_V2_TFT_24BPP_UNPACK		BIT(26)

/* LCD Raster Timing 2 Register */
#define LCD_AC_BIAS_TRANSITIONS_PER_INT(x)	((x) << 16)
#define LCD_AC_BIAS_FREQUENCY(x)		((x) << 8)
#define LCD_SYNC_CTRL				BIT(25)
#define LCD_SYNC_EDGE				BIT(24)
#define LCD_INVERT_PIXEL_CLOCK			BIT(22)
#define LCD_INVERT_LINE_CLOCK			BIT(21)
#define LCD_INVERT_FRAME_CLOCK			BIT(20)

/* LCD Block */
#define  LCD_PID_REG				0x0
#define  LCD_CTRL_REG				0x4
#define  LCD_STAT_REG				0x8
#define  LCD_RASTER_CTRL_REG			0x28
#define  LCD_RASTER_TIMING_0_REG		0x2C
#define  LCD_RASTER_TIMING_1_REG		0x30
#define  LCD_RASTER_TIMING_2_REG		0x34
#define  LCD_DMA_CTRL_REG			0x40
#define  LCD_DMA_FRM_BUF_BASE_ADDR_0_REG	0x44
#define  LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG	0x48
#define  LCD_DMA_FRM_BUF_BASE_ADDR_1_REG	0x4C
#define  LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG	0x50

/* Interrupt Registers available only in Version 2 */
#define  LCD_RAW_STAT_REG			0x58
#define  LCD_MASKED_STAT_REG			0x5c
#define  LCD_INT_ENABLE_SET_REG			0x60
#define  LCD_INT_ENABLE_CLR_REG			0x64
#define  LCD_END_OF_INT_IND_REG			0x68

/* Clock registers available only on Version 2 */
#define  LCD_CLK_ENABLE_REG			0x6c
#define  LCD_CLK_RESET_REG			0x70
#define  LCD_CLK_MAIN_RESET			BIT(3)

#define LCD_NUM_BUFFERS	2

#define PALETTE_SIZE	256

#define	CLK_MIN_DIV	2
#define	CLK_MAX_DIV	255

static void __iomem *da8xx_fb_reg_base;
static unsigned int lcd_revision;
static irq_handler_t lcdc_irq_handler;
static wait_queue_head_t frame_done_wq;
static int frame_done_flag;

static unsigned int lcdc_read(unsigned int addr)
{
	return (unsigned int)__raw_readl(da8xx_fb_reg_base + (addr));
}

static void lcdc_write(unsigned int val, unsigned int addr)
{
	__raw_writel(val, da8xx_fb_reg_base + (addr));
}

struct da8xx_fb_par {
	struct device		*dev;
	dma_addr_t		p_palette_base;
	unsigned char *v_palette_base;
	dma_addr_t		vram_phys;
	unsigned long		vram_size;
	void			*vram_virt;
	unsigned int		dma_start;
	unsigned int		dma_end;
	struct clk *lcdc_clk;
	int irq;
	unsigned int palette_sz;
	int blank;
	wait_queue_head_t	vsync_wait;
	int			vsync_flag;
	int			vsync_timeout;
	spinlock_t		lock_for_chan_update;

	/*
	 * LCDC has 2 ping pong DMA channels, channel 0
	 * and channel 1.
	 */
	unsigned int		which_dma_channel_done;
#ifdef CONFIG_CPU_FREQ
	struct notifier_block	freq_transition;
#endif
	unsigned int		lcdc_clk_rate;
	void (*panel_power_ctrl)(int);
	u32 pseudo_palette[16];
	struct fb_videomode	mode;
	struct lcd_ctrl_config	cfg;
};

static struct fb_var_screeninfo da8xx_fb_var;

static struct fb_fix_screeninfo da8xx_fb_fix = {
	.id = "DA8xx FB Drv",
	.type = FB_TYPE_PACKED_PIXELS,
	.type_aux = 0,
	.visual = FB_VISUAL_PSEUDOCOLOR,
	.xpanstep = 0,
	.ypanstep = 1,
	.ywrapstep = 0,
	.accel = FB_ACCEL_NONE
};

static struct fb_videomode known_lcd_panels[] = {
	/* Sharp LCD035Q3DG01 */
	[0] = {
		.name           = "Sharp_LCD035Q3DG01",
		.xres           = 320,
		.yres           = 240,
		.pixclock       = KHZ2PICOS(4607),
		.left_margin    = 6,
		.right_margin   = 8,
		.upper_margin   = 2,
		.lower_margin   = 2,
		.hsync_len      = 0,
		.vsync_len      = 0,
		.sync           = FB_SYNC_CLK_INVERT,
	},
	/* Sharp LK043T1DG01 */
	[1] = {
		.name           = "Sharp_LK043T1DG01",
		.xres           = 480,
		.yres           = 272,
		.pixclock       = KHZ2PICOS(7833),
		.left_margin    = 2,
		.right_margin   = 2,
		.upper_margin   = 2,
		.lower_margin   = 2,
		.hsync_len      = 41,
		.vsync_len      = 10,
		.sync           = 0,
		.flag           = 0,
	},
	[2] = {
		/* Hitachi SP10Q010 */
		.name           = "SP10Q010",
		.xres           = 320,
		.yres           = 240,
		.pixclock       = KHZ2PICOS(7833),
		.left_margin    = 10,
		.right_margin   = 10,
		.upper_margin   = 10,
		.lower_margin   = 10,
		.hsync_len      = 10,
		.vsync_len      = 10,
		.sync           = 0,
		.flag           = 0,
	},
	[3] = {
		/* Densitron 84-0023-001T */
		.name           = "Densitron_84-0023-001T",
		.xres           = 320,
		.yres           = 240,
		.pixclock       = KHZ2PICOS(6400),
		.left_margin    = 0,
		.right_margin   = 0,
		.upper_margin   = 0,
		.lower_margin   = 0,
		.hsync_len      = 30,
		.vsync_len      = 3,
		.sync           = 0,
	},
};

static bool da8xx_fb_is_raster_enabled(void)
{
	return !!(lcdc_read(LCD_RASTER_CTRL_REG) & LCD_RASTER_ENABLE);
}

/* Enable the Raster Engine of the LCD Controller */
static void lcd_enable_raster(void)
{
	u32 reg;

	/* Put LCDC in reset for several cycles */
	if (lcd_revision == LCD_VERSION_2)
		/* Write 1 to reset LCDC */
		lcdc_write(LCD_CLK_MAIN_RESET, LCD_CLK_RESET_REG);
	mdelay(1);

	/* Bring LCDC out of reset */
	if (lcd_revision == LCD_VERSION_2)
		lcdc_write(0, LCD_CLK_RESET_REG);
	mdelay(1);

	/* Above reset sequence doesnot reset register context */
	reg = lcdc_read(LCD_RASTER_CTRL_REG);
	if (!(reg & LCD_RASTER_ENABLE))
		lcdc_write(reg | LCD_RASTER_ENABLE, LCD_RASTER_CTRL_REG);
}

/* Disable the Raster Engine of the LCD Controller */
static void lcd_disable_raster(enum da8xx_frame_complete wait_for_frame_done)
{
	u32 reg;
	int ret;

	reg = lcdc_read(LCD_RASTER_CTRL_REG);
	if (reg & LCD_RASTER_ENABLE)
		lcdc_write(reg & ~LCD_RASTER_ENABLE, LCD_RASTER_CTRL_REG);
	else
		/* return if already disabled */
		return;

	if ((wait_for_frame_done == DA8XX_FRAME_WAIT) &&
			(lcd_revision == LCD_VERSION_2)) {
		frame_done_flag = 0;
		ret = wait_event_interruptible_timeout(frame_done_wq,
				frame_done_flag != 0,
				msecs_to_jiffies(50));
		if (ret == 0)
			pr_err("LCD Controller timed out\n");
	}
}

static void lcd_blit(int load_mode, struct da8xx_fb_par *par)
{
	u32 start;
	u32 end;
	u32 reg_ras;
	u32 reg_dma;
	u32 reg_int;

	/* init reg to clear PLM (loading mode) fields */
	reg_ras = lcdc_read(LCD_RASTER_CTRL_REG);
	reg_ras &= ~(3 << 20);

	reg_dma  = lcdc_read(LCD_DMA_CTRL_REG);

	if (load_mode == LOAD_DATA) {
		start    = par->dma_start;
		end      = par->dma_end;

		reg_ras |= LCD_PALETTE_LOAD_MODE(DATA_ONLY);
		if (lcd_revision == LCD_VERSION_1) {
			reg_dma |= LCD_V1_END_OF_FRAME_INT_ENA;
		} else {
			reg_int = lcdc_read(LCD_INT_ENABLE_SET_REG) |
				LCD_V2_END_OF_FRAME0_INT_ENA |
				LCD_V2_END_OF_FRAME1_INT_ENA |
				LCD_FRAME_DONE | LCD_SYNC_LOST;
			lcdc_write(reg_int, LCD_INT_ENABLE_SET_REG);
		}
		reg_dma |= LCD_DUAL_FRAME_BUFFER_ENABLE;

		lcdc_write(start, LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
		lcdc_write(end, LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
		lcdc_write(start, LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
		lcdc_write(end, LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
	} else if (load_mode == LOAD_PALETTE) {
		start    = par->p_palette_base;
		end      = start + par->palette_sz - 1;

		reg_ras |= LCD_PALETTE_LOAD_MODE(PALETTE_ONLY);

		if (lcd_revision == LCD_VERSION_1) {
			reg_ras |= LCD_V1_PL_INT_ENA;
		} else {
			reg_int = lcdc_read(LCD_INT_ENABLE_SET_REG) |
				LCD_V2_PL_INT_ENA;
			lcdc_write(reg_int, LCD_INT_ENABLE_SET_REG);
		}

		lcdc_write(start, LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
		lcdc_write(end, LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
	}

	lcdc_write(reg_dma, LCD_DMA_CTRL_REG);
	lcdc_write(reg_ras, LCD_RASTER_CTRL_REG);

	/*
	 * The Raster enable bit must be set after all other control fields are
	 * set.
	 */
	lcd_enable_raster();
}

/* Configure the Burst Size and fifo threhold of DMA */
static int lcd_cfg_dma(int burst_size, int fifo_th)
{
	u32 reg;

	reg = lcdc_read(LCD_DMA_CTRL_REG) & 0x00000001;
	switch (burst_size) {
	case 1:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_1);
		break;
	case 2:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_2);
		break;
	case 4:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_4);
		break;
	case 8:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_8);
		break;
	case 16:
	default:
		reg |= LCD_DMA_BURST_SIZE(LCD_DMA_BURST_16);
		break;
	}

	reg |= (fifo_th << 8);

	lcdc_write(reg, LCD_DMA_CTRL_REG);

	return 0;
}

static void lcd_cfg_ac_bias(int period, int transitions_per_int)
{
	u32 reg;

	/* Set the AC Bias Period and Number of Transisitons per Interrupt */
	reg = lcdc_read(LCD_RASTER_TIMING_2_REG) & 0xFFF00000;
	reg |= LCD_AC_BIAS_FREQUENCY(period) |
		LCD_AC_BIAS_TRANSITIONS_PER_INT(transitions_per_int);
	lcdc_write(reg, LCD_RASTER_TIMING_2_REG);
}

static void lcd_cfg_horizontal_sync(int back_porch, int pulse_width,
		int front_porch)
{
	u32 reg;

	reg = lcdc_read(LCD_RASTER_TIMING_0_REG) & 0x3ff;
	reg |= (((back_porch-1) & 0xff) << 24)
	    | (((front_porch-1) & 0xff) << 16)
	    | (((pulse_width-1) & 0x3f) << 10);
	lcdc_write(reg, LCD_RASTER_TIMING_0_REG);

	/*
	 * LCDC Version 2 adds some extra bits that increase the allowable
	 * size of the horizontal timing registers.
	 * remember that the registers use 0 to represent 1 so all values
	 * that get set into register need to be decremented by 1
	 */
	if (lcd_revision == LCD_VERSION_2) {
		/* Mask off the bits we want to change */
		reg = lcdc_read(LCD_RASTER_TIMING_2_REG) & ~0x780000ff;
		reg |= ((front_porch-1) & 0x300) >> 8;
		reg |= ((back_porch-1) & 0x300) >> 4;
		reg |= ((pulse_width-1) & 0x3c0) << 21;
		lcdc_write(reg, LCD_RASTER_TIMING_2_REG);
	}
}

static void lcd_cfg_vertical_sync(int back_porch, int pulse_width,
		int front_porch)
{
	u32 reg;

	reg = lcdc_read(LCD_RASTER_TIMING_1_REG) & 0x3ff;
	reg |= ((back_porch & 0xff) << 24)
	    | ((front_porch & 0xff) << 16)
	    | (((pulse_width-1) & 0x3f) << 10);
	lcdc_write(reg, LCD_RASTER_TIMING_1_REG);
}

static int lcd_cfg_display(const struct lcd_ctrl_config *cfg,
		struct fb_videomode *panel)
{
	u32 reg;
	u32 reg_int;

	reg = lcdc_read(LCD_RASTER_CTRL_REG) & ~(LCD_TFT_MODE |
						LCD_MONO_8BIT_MODE |
						LCD_MONOCHROME_MODE);

	switch (cfg->panel_shade) {
	case MONOCHROME:
		reg |= LCD_MONOCHROME_MODE;
		if (cfg->mono_8bit_mode)
			reg |= LCD_MONO_8BIT_MODE;
		break;
	case COLOR_ACTIVE:
		reg |= LCD_TFT_MODE;
		if (cfg->tft_alt_mode)
			reg |= LCD_TFT_ALT_ENABLE;
		break;

	case COLOR_PASSIVE:
		/* AC bias applicable only for Pasive panels */
		lcd_cfg_ac_bias(cfg->ac_bias, cfg->ac_bias_intrpt);
		if (cfg->bpp == 12 && cfg->stn_565_mode)
			reg |= LCD_STN_565_ENABLE;
		break;

	default:
		return -EINVAL;
	}

	/* enable additional interrupts here */
	if (lcd_revision == LCD_VERSION_1) {
		reg |= LCD_V1_UNDERFLOW_INT_ENA;
	} else {
		reg_int = lcdc_read(LCD_INT_ENABLE_SET_REG) |
			LCD_V2_UNDERFLOW_INT_ENA;
		lcdc_write(reg_int, LCD_INT_ENABLE_SET_REG);
	}

	lcdc_write(reg, LCD_RASTER_CTRL_REG);

	reg = lcdc_read(LCD_RASTER_TIMING_2_REG);

	reg |= LCD_SYNC_CTRL;

	if (cfg->sync_edge)
		reg |= LCD_SYNC_EDGE;
	else
		reg &= ~LCD_SYNC_EDGE;

	if ((panel->sync & FB_SYNC_HOR_HIGH_ACT) == 0)
		reg |= LCD_INVERT_LINE_CLOCK;
	else
		reg &= ~LCD_INVERT_LINE_CLOCK;

	if ((panel->sync & FB_SYNC_VERT_HIGH_ACT) == 0)
		reg |= LCD_INVERT_FRAME_CLOCK;
	else
		reg &= ~LCD_INVERT_FRAME_CLOCK;

	lcdc_write(reg, LCD_RASTER_TIMING_2_REG);

	return 0;
}

static int lcd_cfg_frame_buffer(struct da8xx_fb_par *par, u32 width, u32 height,
		u32 bpp, u32 raster_order)
{
	u32 reg;

	if (bpp > 16 && lcd_revision == LCD_VERSION_1)
		return -EINVAL;

	/* Set the Panel Width */
	/* Pixels per line = (PPL + 1)*16 */
	if (lcd_revision == LCD_VERSION_1) {
		/*
		 * 0x3F in bits 4..9 gives max horizontal resolution = 1024
		 * pixels.
		 */
		width &= 0x3f0;
	} else {
		/*
		 * 0x7F in bits 4..10 gives max horizontal resolution = 2048
		 * pixels.
		 */
		width &= 0x7f0;
	}

	reg = lcdc_read(LCD_RASTER_TIMING_0_REG);
	reg &= 0xfffffc00;
	if (lcd_revision == LCD_VERSION_1) {
		reg |= ((width >> 4) - 1) << 4;
	} else {
		width = (width >> 4) - 1;
		reg |= ((width & 0x3f) << 4) | ((width & 0x40) >> 3);
	}
	lcdc_write(reg, LCD_RASTER_TIMING_0_REG);

	/* Set the Panel Height */
	/* Set bits 9:0 of Lines Per Pixel */
	reg = lcdc_read(LCD_RASTER_TIMING_1_REG);
	reg = ((height - 1) & 0x3ff) | (reg & 0xfffffc00);
	lcdc_write(reg, LCD_RASTER_TIMING_1_REG);

	/* Set bit 10 of Lines Per Pixel */
	if (lcd_revision == LCD_VERSION_2) {
		reg = lcdc_read(LCD_RASTER_TIMING_2_REG);
		reg |= ((height - 1) & 0x400) << 16;
		lcdc_write(reg, LCD_RASTER_TIMING_2_REG);
	}

	/* Set the Raster Order of the Frame Buffer */
	reg = lcdc_read(LCD_RASTER_CTRL_REG) & ~(1 << 8);
	if (raster_order)
		reg |= LCD_RASTER_ORDER;

	par->palette_sz = 16 * 2;

	switch (bpp) {
	case 1:
	case 2:
	case 4:
	case 16:
		break;
	case 24:
		reg |= LCD_V2_TFT_24BPP_MODE;
		break;
	case 32:
		reg |= LCD_V2_TFT_24BPP_MODE;
		reg |= LCD_V2_TFT_24BPP_UNPACK;
		break;
	case 8:
		par->palette_sz = 256 * 2;
		break;

	default:
		return -EINVAL;
	}

	lcdc_write(reg, LCD_RASTER_CTRL_REG);

	return 0;
}

#define CNVT_TOHW(val, width) ((((val) << (width)) + 0x7FFF - (val)) >> 16)
static int fb_setcolreg(unsigned regno, unsigned red, unsigned green,
			      unsigned blue, unsigned transp,
			      struct fb_info *info)
{
	struct da8xx_fb_par *par = info->par;
	unsigned short *palette = (unsigned short *) par->v_palette_base;
	u_short pal;
	int update_hw = 0;

	if (regno > 255)
		return 1;

	if (info->fix.visual == FB_VISUAL_DIRECTCOLOR)
		return 1;

	if (info->var.bits_per_pixel > 16 && lcd_revision == LCD_VERSION_1)
		return -EINVAL;

	switch (info->fix.visual) {
	case FB_VISUAL_TRUECOLOR:
		red = CNVT_TOHW(red, info->var.red.length);
		green = CNVT_TOHW(green, info->var.green.length);
		blue = CNVT_TOHW(blue, info->var.blue.length);
		break;
	case FB_VISUAL_PSEUDOCOLOR:
		switch (info->var.bits_per_pixel) {
		case 4:
			if (regno > 15)
				return -EINVAL;

			if (info->var.grayscale) {
				pal = regno;
			} else {
				red >>= 4;
				green >>= 8;
				blue >>= 12;

				pal = red & 0x0f00;
				pal |= green & 0x00f0;
				pal |= blue & 0x000f;
			}
			if (regno == 0)
				pal |= 0x2000;
			palette[regno] = pal;
			break;

		case 8:
			red >>= 4;
			green >>= 8;
			blue >>= 12;

			pal = (red & 0x0f00);
			pal |= (green & 0x00f0);
			pal |= (blue & 0x000f);

			if (palette[regno] != pal) {
				update_hw = 1;
				palette[regno] = pal;
			}
			break;
		}
		break;
	}

	/* Truecolor has hardware independent palette */
	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
		u32 v;

		if (regno > 15)
			return -EINVAL;

		v = (red << info->var.red.offset) |
			(green << info->var.green.offset) |
			(blue << info->var.blue.offset);

		((u32 *) (info->pseudo_palette))[regno] = v;
		if (palette[0] != 0x4000) {
			update_hw = 1;
			palette[0] = 0x4000;
		}
	}

	/* Update the palette in the h/w as needed. */
	if (update_hw)
		lcd_blit(LOAD_PALETTE, par);

	return 0;
}
#undef CNVT_TOHW

static void da8xx_fb_lcd_reset(void)
{
	/* DMA has to be disabled */
	lcdc_write(0, LCD_DMA_CTRL_REG);
	lcdc_write(0, LCD_RASTER_CTRL_REG);

	if (lcd_revision == LCD_VERSION_2) {
		lcdc_write(0, LCD_INT_ENABLE_SET_REG);
		/* Write 1 to reset */
		lcdc_write(LCD_CLK_MAIN_RESET, LCD_CLK_RESET_REG);
		lcdc_write(0, LCD_CLK_RESET_REG);
	}
}

static int da8xx_fb_config_clk_divider(struct da8xx_fb_par *par,
					      unsigned lcdc_clk_div,
					      unsigned lcdc_clk_rate)
{
	int ret;

	if (par->lcdc_clk_rate != lcdc_clk_rate) {
		ret = clk_set_rate(par->lcdc_clk, lcdc_clk_rate);
		if (ret) {
			dev_err(par->dev,
				"unable to set clock rate at %u\n",
				lcdc_clk_rate);
			return ret;
		}
		par->lcdc_clk_rate = clk_get_rate(par->lcdc_clk);
	}

	/* Configure the LCD clock divisor. */
	lcdc_write(LCD_CLK_DIVISOR(lcdc_clk_div) |
			(LCD_RASTER_MODE & 0x1), LCD_CTRL_REG);

	if (lcd_revision == LCD_VERSION_2)
		lcdc_write(LCD_V2_DMA_CLK_EN | LCD_V2_LIDD_CLK_EN |
				LCD_V2_CORE_CLK_EN, LCD_CLK_ENABLE_REG);

	return 0;
}

static unsigned int da8xx_fb_calc_clk_divider(struct da8xx_fb_par *par,
					      unsigned pixclock,
					      unsigned *lcdc_clk_rate)
{
	unsigned lcdc_clk_div;

	pixclock = PICOS2KHZ(pixclock) * 1000;

	*lcdc_clk_rate = par->lcdc_clk_rate;

	if (pixclock < (*lcdc_clk_rate / CLK_MAX_DIV)) {
		*lcdc_clk_rate = clk_round_rate(par->lcdc_clk,
						pixclock * CLK_MAX_DIV);
		lcdc_clk_div = CLK_MAX_DIV;
	} else if (pixclock > (*lcdc_clk_rate / CLK_MIN_DIV)) {
		*lcdc_clk_rate = clk_round_rate(par->lcdc_clk,
						pixclock * CLK_MIN_DIV);
		lcdc_clk_div = CLK_MIN_DIV;
	} else {
		lcdc_clk_div = *lcdc_clk_rate / pixclock;
	}

	return lcdc_clk_div;
}

static int da8xx_fb_calc_config_clk_divider(struct da8xx_fb_par *par,
					    struct fb_videomode *mode)
{
	unsigned lcdc_clk_rate;
	unsigned lcdc_clk_div = da8xx_fb_calc_clk_divider(par, mode->pixclock,
							  &lcdc_clk_rate);

	return da8xx_fb_config_clk_divider(par, lcdc_clk_div, lcdc_clk_rate);
}

static unsigned da8xx_fb_round_clk(struct da8xx_fb_par *par,
					  unsigned pixclock)
{
	unsigned lcdc_clk_div, lcdc_clk_rate;

	lcdc_clk_div = da8xx_fb_calc_clk_divider(par, pixclock, &lcdc_clk_rate);
	return KHZ2PICOS(lcdc_clk_rate / (1000 * lcdc_clk_div));
}

static int lcd_init(struct da8xx_fb_par *par, const struct lcd_ctrl_config *cfg,
		struct fb_videomode *panel)
{
	u32 bpp;
	int ret = 0;

	ret = da8xx_fb_calc_config_clk_divider(par, panel);
	if (ret) {
		dev_err(par->dev, "unable to configure clock\n");
		return ret;
	}

	if (panel->sync & FB_SYNC_CLK_INVERT)
		lcdc_write((lcdc_read(LCD_RASTER_TIMING_2_REG) |
			LCD_INVERT_PIXEL_CLOCK), LCD_RASTER_TIMING_2_REG);
	else
		lcdc_write((lcdc_read(LCD_RASTER_TIMING_2_REG) &
			~LCD_INVERT_PIXEL_CLOCK), LCD_RASTER_TIMING_2_REG);

	/* Configure the DMA burst size and fifo threshold. */
	ret = lcd_cfg_dma(cfg->dma_burst_sz, cfg->fifo_th);
	if (ret < 0)
		return ret;

	/* Configure the vertical and horizontal sync properties. */
	lcd_cfg_vertical_sync(panel->upper_margin, panel->vsync_len,
			panel->lower_margin);
	lcd_cfg_horizontal_sync(panel->left_margin, panel->hsync_len,
			panel->right_margin);

	/* Configure for disply */
	ret = lcd_cfg_display(cfg, panel);
	if (ret < 0)
		return ret;

	bpp = cfg->bpp;

	if (bpp == 12)
		bpp = 16;
	ret = lcd_cfg_frame_buffer(par, (unsigned int)panel->xres,
				(unsigned int)panel->yres, bpp,
				cfg->raster_order);
	if (ret < 0)
		return ret;

	/* Configure FDD */
	lcdc_write((lcdc_read(LCD_RASTER_CTRL_REG) & 0xfff00fff) |
		       (cfg->fdd << 12), LCD_RASTER_CTRL_REG);

	return 0;
}

/* IRQ handler for version 2 of LCDC */
static irqreturn_t lcdc_irq_handler_rev02(int irq, void *arg)
{
	struct da8xx_fb_par *par = arg;
	u32 stat = lcdc_read(LCD_MASKED_STAT_REG);

	if ((stat & LCD_SYNC_LOST) && (stat & LCD_FIFO_UNDERFLOW)) {
		lcd_disable_raster(DA8XX_FRAME_NOWAIT);
		lcdc_write(stat, LCD_MASKED_STAT_REG);
		lcd_enable_raster();
	} else if (stat & LCD_PL_LOAD_DONE) {
		/*
		 * Must disable raster before changing state of any control bit.
		 * And also must be disabled before clearing the PL loading
		 * interrupt via the following write to the status register. If
		 * this is done after then one gets multiple PL done interrupts.
		 */
		lcd_disable_raster(DA8XX_FRAME_NOWAIT);

		lcdc_write(stat, LCD_MASKED_STAT_REG);

		/* Disable PL completion interrupt */
		lcdc_write(LCD_V2_PL_INT_ENA, LCD_INT_ENABLE_CLR_REG);

		/* Setup and start data loading mode */
		lcd_blit(LOAD_DATA, par);
	} else {
		lcdc_write(stat, LCD_MASKED_STAT_REG);

		if (stat & LCD_END_OF_FRAME0) {
			par->which_dma_channel_done = 0;
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}

		if (stat & LCD_END_OF_FRAME1) {
			par->which_dma_channel_done = 1;
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}

		/* Set only when controller is disabled and at the end of
		 * active frame
		 */
		if (stat & BIT(0)) {
			frame_done_flag = 1;
			wake_up_interruptible(&frame_done_wq);
		}
	}

	lcdc_write(0, LCD_END_OF_INT_IND_REG);
	return IRQ_HANDLED;
}

/* IRQ handler for version 1 LCDC */
static irqreturn_t lcdc_irq_handler_rev01(int irq, void *arg)
{
	struct da8xx_fb_par *par = arg;
	u32 stat = lcdc_read(LCD_STAT_REG);
	u32 reg_ras;

	if ((stat & LCD_SYNC_LOST) && (stat & LCD_FIFO_UNDERFLOW)) {
		lcd_disable_raster(DA8XX_FRAME_NOWAIT);
		lcdc_write(stat, LCD_STAT_REG);
		lcd_enable_raster();
	} else if (stat & LCD_PL_LOAD_DONE) {
		/*
		 * Must disable raster before changing state of any control bit.
		 * And also must be disabled before clearing the PL loading
		 * interrupt via the following write to the status register. If
		 * this is done after then one gets multiple PL done interrupts.
		 */
		lcd_disable_raster(DA8XX_FRAME_NOWAIT);

		lcdc_write(stat, LCD_STAT_REG);

		/* Disable PL completion inerrupt */
		reg_ras  = lcdc_read(LCD_RASTER_CTRL_REG);
		reg_ras &= ~LCD_V1_PL_INT_ENA;
		lcdc_write(reg_ras, LCD_RASTER_CTRL_REG);

		/* Setup and start data loading mode */
		lcd_blit(LOAD_DATA, par);
	} else {
		lcdc_write(stat, LCD_STAT_REG);

		if (stat & LCD_END_OF_FRAME0) {
			par->which_dma_channel_done = 0;
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}

		if (stat & LCD_END_OF_FRAME1) {
			par->which_dma_channel_done = 1;
			lcdc_write(par->dma_start,
				   LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
			lcdc_write(par->dma_end,
				   LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
			par->vsync_flag = 1;
			wake_up_interruptible(&par->vsync_wait);
		}
	}

	return IRQ_HANDLED;
}

static int fb_check_var(struct fb_var_screeninfo *var,
			struct fb_info *info)
{
	int err = 0;
	struct da8xx_fb_par *par = info->par;
	int bpp = var->bits_per_pixel >> 3;
	unsigned long line_size = var->xres_virtual * bpp;

	if (var->bits_per_pixel > 16 && lcd_revision == LCD_VERSION_1)
		return -EINVAL;

	switch (var->bits_per_pixel) {
	case 1:
	case 8:
		var->red.offset = 0;
		var->red.length = 8;
		var->green.offset = 0;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 0;
		var->nonstd = 0;
		break;
	case 4:
		var->red.offset = 0;
		var->red.length = 4;
		var->green.offset = 0;
		var->green.length = 4;
		var->blue.offset = 0;
		var->blue.length = 4;
		var->transp.offset = 0;
		var->transp.length = 0;
		var->nonstd = FB_NONSTD_REV_PIX_IN_B;
		break;
	case 16:		/* RGB 565 */
		var->red.offset = 11;
		var->red.length = 5;
		var->green.offset = 5;
		var->green.length = 6;
		var->blue.offset = 0;
		var->blue.length = 5;
		var->transp.offset = 0;
		var->transp.length = 0;
		var->nonstd = 0;
		break;
	case 24:
		var->red.offset = 16;
		var->red.length = 8;
		var->green.offset = 8;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->nonstd = 0;
		break;
	case 32:
		var->transp.offset = 24;
		var->transp.length = 8;
		var->red.offset = 16;
		var->red.length = 8;
		var->green.offset = 8;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->nonstd = 0;
		break;
	default:
		err = -EINVAL;
	}

	var->red.msb_right = 0;
	var->green.msb_right = 0;
	var->blue.msb_right = 0;
	var->transp.msb_right = 0;

	if (line_size * var->yres_virtual > par->vram_size)
		var->yres_virtual = par->vram_size / line_size;

	if (var->yres > var->yres_virtual)
		var->yres = var->yres_virtual;

	if (var->xres > var->xres_virtual)
		var->xres = var->xres_virtual;

	if (var->xres + var->xoffset > var->xres_virtual)
		var->xoffset = var->xres_virtual - var->xres;
	if (var->yres + var->yoffset > var->yres_virtual)
		var->yoffset = var->yres_virtual - var->yres;

	var->pixclock = da8xx_fb_round_clk(par, var->pixclock);

	return err;
}

#ifdef CONFIG_CPU_FREQ
static int lcd_da8xx_cpufreq_transition(struct notifier_block *nb,
				     unsigned long val, void *data)
{
	struct da8xx_fb_par *par;

	par = container_of(nb, struct da8xx_fb_par, freq_transition);
	if (val == CPUFREQ_POSTCHANGE) {
		if (par->lcdc_clk_rate != clk_get_rate(par->lcdc_clk)) {
			par->lcdc_clk_rate = clk_get_rate(par->lcdc_clk);
			lcd_disable_raster(DA8XX_FRAME_WAIT);
			da8xx_fb_calc_config_clk_divider(par, &par->mode);
			if (par->blank == FB_BLANK_UNBLANK)
				lcd_enable_raster();
		}
	}

	return 0;
}

static int lcd_da8xx_cpufreq_register(struct da8xx_fb_par *par)
{
	par->freq_transition.notifier_call = lcd_da8xx_cpufreq_transition;

	return cpufreq_register_notifier(&par->freq_transition,
					 CPUFREQ_TRANSITION_NOTIFIER);
}

static void lcd_da8xx_cpufreq_deregister(struct da8xx_fb_par *par)
{
	cpufreq_unregister_notifier(&par->freq_transition,
				    CPUFREQ_TRANSITION_NOTIFIER);
}
#endif

static int fb_remove(struct platform_device *dev)
{
	struct fb_info *info = dev_get_drvdata(&dev->dev);

	if (info) {
		struct da8xx_fb_par *par = info->par;

#ifdef CONFIG_CPU_FREQ
		lcd_da8xx_cpufreq_deregister(par);
#endif
		if (par->panel_power_ctrl)
			par->panel_power_ctrl(0);

		lcd_disable_raster(DA8XX_FRAME_WAIT);
		lcdc_write(0, LCD_RASTER_CTRL_REG);

		/* disable DMA  */
		lcdc_write(0, LCD_DMA_CTRL_REG);

		unregister_framebuffer(info);
		fb_dealloc_cmap(&info->cmap);
		dma_free_coherent(par->dev, PALETTE_SIZE, par->v_palette_base,
				  par->p_palette_base);
		dma_free_coherent(par->dev, par->vram_size, par->vram_virt,
				  par->vram_phys);
		pm_runtime_put_sync(&dev->dev);
		pm_runtime_disable(&dev->dev);
		framebuffer_release(info);

	}
	return 0;
}

/*
 * Function to wait for vertical sync which for this LCD peripheral
 * translates into waiting for the current raster frame to complete.
 */
static int fb_wait_for_vsync(struct fb_info *info)
{
	struct da8xx_fb_par *par = info->par;
	int ret;

	/*
	 * Set flag to 0 and wait for isr to set to 1. It would seem there is a
	 * race condition here where the ISR could have occurred just before or
	 * just after this set. But since we are just coarsely waiting for
	 * a frame to complete then that's OK. i.e. if the frame completed
	 * just before this code executed then we have to wait another full
	 * frame time but there is no way to avoid such a situation. On the
	 * other hand if the frame completed just after then we don't need
	 * to wait long at all. Either way we are guaranteed to return to the
	 * user immediately after a frame completion which is all that is
	 * required.
	 */
	par->vsync_flag = 0;
	ret = wait_event_interruptible_timeout(par->vsync_wait,
					       par->vsync_flag != 0,
					       par->vsync_timeout);
	if (ret < 0)
		return ret;
	if (ret == 0)
		return -ETIMEDOUT;

	return 0;
}

static int fb_ioctl(struct fb_info *info, unsigned int cmd,
			  unsigned long arg)
{
	struct lcd_sync_arg sync_arg;

	switch (cmd) {
	case FBIOGET_CONTRAST:
	case FBIOPUT_CONTRAST:
	case FBIGET_BRIGHTNESS:
	case FBIPUT_BRIGHTNESS:
	case FBIGET_COLOR:
	case FBIPUT_COLOR:
		return -ENOTTY;
	case FBIPUT_HSYNC:
		if (copy_from_user(&sync_arg, (char *)arg,
				sizeof(struct lcd_sync_arg)))
			return -EFAULT;
		lcd_cfg_horizontal_sync(sync_arg.back_porch,
					sync_arg.pulse_width,
					sync_arg.front_porch);
		break;
	case FBIPUT_VSYNC:
		if (copy_from_user(&sync_arg, (char *)arg,
				sizeof(struct lcd_sync_arg)))
			return -EFAULT;
		lcd_cfg_vertical_sync(sync_arg.back_porch,
					sync_arg.pulse_width,
					sync_arg.front_porch);
		break;
	case FBIO_WAITFORVSYNC:
		return fb_wait_for_vsync(info);
	default:
		return -EINVAL;
	}
	return 0;
}

static int cfb_blank(int blank, struct fb_info *info)
{
	struct da8xx_fb_par *par = info->par;
	int ret = 0;

	if (par->blank == blank)
		return 0;

	par->blank = blank;
	switch (blank) {
	case FB_BLANK_UNBLANK:
		lcd_enable_raster();

		if (par->panel_power_ctrl)
			par->panel_power_ctrl(1);
		break;
	case FB_BLANK_NORMAL:
	case FB_BLANK_VSYNC_SUSPEND:
	case FB_BLANK_HSYNC_SUSPEND:
	case FB_BLANK_POWERDOWN:
		if (par->panel_power_ctrl)
			par->panel_power_ctrl(0);

		lcd_disable_raster(DA8XX_FRAME_WAIT);
		break;
	default:
		ret = -EINVAL;
	}

	return ret;
}

/*
 * Set new x,y offsets in the virtual display for the visible area and switch
 * to the new mode.
 */
static int da8xx_pan_display(struct fb_var_screeninfo *var,
			     struct fb_info *fbi)
{
	int ret = 0;
	struct fb_var_screeninfo new_var;
	struct da8xx_fb_par         *par = fbi->par;
	struct fb_fix_screeninfo    *fix = &fbi->fix;
	unsigned int end;
	unsigned int start;
	unsigned long irq_flags;

	if (var->xoffset != fbi->var.xoffset ||
			var->yoffset != fbi->var.yoffset) {
		memcpy(&new_var, &fbi->var, sizeof(new_var));
		new_var.xoffset = var->xoffset;
		new_var.yoffset = var->yoffset;
		if (fb_check_var(&new_var, fbi))
			ret = -EINVAL;
		else {
			memcpy(&fbi->var, &new_var, sizeof(new_var));

			start	= fix->smem_start +
				new_var.yoffset * fix->line_length +
				new_var.xoffset * fbi->var.bits_per_pixel / 8;
			end	= start + fbi->var.yres * fix->line_length - 1;
			par->dma_start	= start;
			par->dma_end	= end;
			spin_lock_irqsave(&par->lock_for_chan_update,
					irq_flags);
			if (par->which_dma_channel_done == 0) {
				lcdc_write(par->dma_start,
					   LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
				lcdc_write(par->dma_end,
					   LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
			} else if (par->which_dma_channel_done == 1) {
				lcdc_write(par->dma_start,
					   LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
				lcdc_write(par->dma_end,
					   LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
			}
			spin_unlock_irqrestore(&par->lock_for_chan_update,
					irq_flags);
		}
	}

	return ret;
}

static int da8xxfb_set_par(struct fb_info *info)
{
	struct da8xx_fb_par *par = info->par;
	int ret;
	bool raster = da8xx_fb_is_raster_enabled();

	if (raster)
		lcd_disable_raster(DA8XX_FRAME_WAIT);

	fb_var_to_videomode(&par->mode, &info->var);

	par->cfg.bpp = info->var.bits_per_pixel;

	info->fix.visual = (par->cfg.bpp <= 8) ?
				FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR;
	info->fix.line_length = (par->mode.xres * par->cfg.bpp) / 8;

	ret = lcd_init(par, &par->cfg, &par->mode);
	if (ret < 0) {
		dev_err(par->dev, "lcd init failed\n");
		return ret;
	}

	par->dma_start = info->fix.smem_start +
			 info->var.yoffset * info->fix.line_length +
			 info->var.xoffset * info->var.bits_per_pixel / 8;
	par->dma_end   = par->dma_start +
			 info->var.yres * info->fix.line_length - 1;

	lcdc_write(par->dma_start, LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
	lcdc_write(par->dma_end, LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
	lcdc_write(par->dma_start, LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
	lcdc_write(par->dma_end, LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);

	if (raster)
		lcd_enable_raster();

	return 0;
}

static struct fb_ops da8xx_fb_ops = {
	.owner = THIS_MODULE,
	.fb_check_var = fb_check_var,
	.fb_set_par = da8xxfb_set_par,
	.fb_setcolreg = fb_setcolreg,
	.fb_pan_display = da8xx_pan_display,
	.fb_ioctl = fb_ioctl,
	.fb_fillrect = cfb_fillrect,
	.fb_copyarea = cfb_copyarea,
	.fb_imageblit = cfb_imageblit,
	.fb_blank = cfb_blank,
};

static struct fb_videomode *da8xx_fb_get_videomode(struct platform_device *dev)
{
	struct da8xx_lcdc_platform_data *fb_pdata = dev_get_platdata(&dev->dev);
	struct fb_videomode *lcdc_info;
	int i;

	for (i = 0, lcdc_info = known_lcd_panels;
		i < ARRAY_SIZE(known_lcd_panels); i++, lcdc_info++) {
		if (strcmp(fb_pdata->type, lcdc_info->name) == 0)
			break;
	}

	if (i == ARRAY_SIZE(known_lcd_panels)) {
		dev_err(&dev->dev, "no panel found\n");
		return NULL;
	}
	dev_info(&dev->dev, "found %s panel\n", lcdc_info->name);

	return lcdc_info;
}

static int fb_probe(struct platform_device *device)
{
	struct da8xx_lcdc_platform_data *fb_pdata =
						dev_get_platdata(&device->dev);
	struct resource *lcdc_regs;
	struct lcd_ctrl_config *lcd_cfg;
	struct fb_videomode *lcdc_info;
	struct fb_info *da8xx_fb_info;
	struct da8xx_fb_par *par;
	struct clk *tmp_lcdc_clk;
	int ret;
	unsigned long ulcm;

	if (fb_pdata == NULL) {
		dev_err(&device->dev, "Can not get platform data\n");
		return -ENOENT;
	}

	lcdc_info = da8xx_fb_get_videomode(device);
	if (lcdc_info == NULL)
		return -ENODEV;

	lcdc_regs = platform_get_resource(device, IORESOURCE_MEM, 0);
	da8xx_fb_reg_base = devm_ioremap_resource(&device->dev, lcdc_regs);
	if (IS_ERR(da8xx_fb_reg_base))
		return PTR_ERR(da8xx_fb_reg_base);

	tmp_lcdc_clk = devm_clk_get(&device->dev, "fck");
	if (IS_ERR(tmp_lcdc_clk)) {
		dev_err(&device->dev, "Can not get device clock\n");
		return PTR_ERR(tmp_lcdc_clk);
	}

	pm_runtime_enable(&device->dev);
	pm_runtime_get_sync(&device->dev);

	/* Determine LCD IP Version */
	switch (lcdc_read(LCD_PID_REG)) {
	case 0x4C100102:
		lcd_revision = LCD_VERSION_1;
		break;
	case 0x4F200800:
	case 0x4F201000:
		lcd_revision = LCD_VERSION_2;
		break;
	default:
		dev_warn(&device->dev, "Unknown PID Reg value 0x%x, "
				"defaulting to LCD revision 1\n",
				lcdc_read(LCD_PID_REG));
		lcd_revision = LCD_VERSION_1;
		break;
	}

	lcd_cfg = (struct lcd_ctrl_config *)fb_pdata->controller_data;

	if (!lcd_cfg) {
		ret = -EINVAL;
		goto err_pm_runtime_disable;
	}

	da8xx_fb_info = framebuffer_alloc(sizeof(struct da8xx_fb_par),
					&device->dev);
	if (!da8xx_fb_info) {
		dev_dbg(&device->dev, "Memory allocation failed for fb_info\n");
		ret = -ENOMEM;
		goto err_pm_runtime_disable;
	}

	par = da8xx_fb_info->par;
	par->dev = &device->dev;
	par->lcdc_clk = tmp_lcdc_clk;
	par->lcdc_clk_rate = clk_get_rate(par->lcdc_clk);
	if (fb_pdata->panel_power_ctrl) {
		par->panel_power_ctrl = fb_pdata->panel_power_ctrl;
		par->panel_power_ctrl(1);
	}

	fb_videomode_to_var(&da8xx_fb_var, lcdc_info);
	par->cfg = *lcd_cfg;

	da8xx_fb_lcd_reset();

	/* allocate frame buffer */
	par->vram_size = lcdc_info->xres * lcdc_info->yres * lcd_cfg->bpp;
	ulcm = lcm((lcdc_info->xres * lcd_cfg->bpp)/8, PAGE_SIZE);
	par->vram_size = roundup(par->vram_size/8, ulcm);
	par->vram_size = par->vram_size * LCD_NUM_BUFFERS;

	par->vram_virt = dma_alloc_coherent(par->dev,
					    par->vram_size,
					    &par->vram_phys,
					    GFP_KERNEL | GFP_DMA);
	if (!par->vram_virt) {
		dev_err(&device->dev,
			"GLCD: kmalloc for frame buffer failed\n");
		ret = -EINVAL;
		goto err_release_fb;
	}

	da8xx_fb_info->screen_base = (char __iomem *) par->vram_virt;
	da8xx_fb_fix.smem_start    = par->vram_phys;
	da8xx_fb_fix.smem_len      = par->vram_size;
	da8xx_fb_fix.line_length   = (lcdc_info->xres * lcd_cfg->bpp) / 8;

	par->dma_start = par->vram_phys;
	par->dma_end   = par->dma_start + lcdc_info->yres *
		da8xx_fb_fix.line_length - 1;

	/* allocate palette buffer */
	par->v_palette_base = dma_alloc_coherent(par->dev, PALETTE_SIZE,
						 &par->p_palette_base,
						 GFP_KERNEL | GFP_DMA);
	if (!par->v_palette_base) {
		dev_err(&device->dev,
			"GLCD: kmalloc for palette buffer failed\n");
		ret = -EINVAL;
		goto err_release_fb_mem;
	}

	par->irq = platform_get_irq(device, 0);
	if (par->irq < 0) {
		ret = -ENOENT;
		goto err_release_pl_mem;
	}

	da8xx_fb_var.grayscale =
	    lcd_cfg->panel_shade == MONOCHROME ? 1 : 0;
	da8xx_fb_var.bits_per_pixel = lcd_cfg->bpp;

	/* Initialize fbinfo */
	da8xx_fb_info->flags = FBINFO_FLAG_DEFAULT;
	da8xx_fb_info->fix = da8xx_fb_fix;
	da8xx_fb_info->var = da8xx_fb_var;
	da8xx_fb_info->fbops = &da8xx_fb_ops;
	da8xx_fb_info->pseudo_palette = par->pseudo_palette;
	da8xx_fb_info->fix.visual = (da8xx_fb_info->var.bits_per_pixel <= 8) ?
				FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR;

	ret = fb_alloc_cmap(&da8xx_fb_info->cmap, PALETTE_SIZE, 0);
	if (ret)
		goto err_release_pl_mem;
	da8xx_fb_info->cmap.len = par->palette_sz;

	/* initialize var_screeninfo */
	da8xx_fb_var.activate = FB_ACTIVATE_FORCE;
	fb_set_var(da8xx_fb_info, &da8xx_fb_var);

	dev_set_drvdata(&device->dev, da8xx_fb_info);

	/* initialize the vsync wait queue */
	init_waitqueue_head(&par->vsync_wait);
	par->vsync_timeout = HZ / 5;
	par->which_dma_channel_done = -1;
	spin_lock_init(&par->lock_for_chan_update);

	/* Register the Frame Buffer  */
	if (register_framebuffer(da8xx_fb_info) < 0) {
		dev_err(&device->dev,
			"GLCD: Frame Buffer Registration Failed!\n");
		ret = -EINVAL;
		goto err_dealloc_cmap;
	}

#ifdef CONFIG_CPU_FREQ
	ret = lcd_da8xx_cpufreq_register(par);
	if (ret) {
		dev_err(&device->dev, "failed to register cpufreq\n");
		goto err_cpu_freq;
	}
#endif

	if (lcd_revision == LCD_VERSION_1)
		lcdc_irq_handler = lcdc_irq_handler_rev01;
	else {
		init_waitqueue_head(&frame_done_wq);
		lcdc_irq_handler = lcdc_irq_handler_rev02;
	}

	ret = devm_request_irq(&device->dev, par->irq, lcdc_irq_handler, 0,
			       DRIVER_NAME, par);
	if (ret)
		goto irq_freq;
	return 0;

irq_freq:
#ifdef CONFIG_CPU_FREQ
	lcd_da8xx_cpufreq_deregister(par);
err_cpu_freq:
#endif
	unregister_framebuffer(da8xx_fb_info);

err_dealloc_cmap:
	fb_dealloc_cmap(&da8xx_fb_info->cmap);

err_release_pl_mem:
	dma_free_coherent(par->dev, PALETTE_SIZE, par->v_palette_base,
			  par->p_palette_base);

err_release_fb_mem:
	dma_free_coherent(par->dev, par->vram_size, par->vram_virt,
		          par->vram_phys);

err_release_fb:
	framebuffer_release(da8xx_fb_info);

err_pm_runtime_disable:
	pm_runtime_put_sync(&device->dev);
	pm_runtime_disable(&device->dev);

	return ret;
}

#ifdef CONFIG_PM_SLEEP
static struct lcdc_context {
	u32 clk_enable;
	u32 ctrl;
	u32 dma_ctrl;
	u32 raster_timing_0;
	u32 raster_timing_1;
	u32 raster_timing_2;
	u32 int_enable_set;
	u32 dma_frm_buf_base_addr_0;
	u32 dma_frm_buf_ceiling_addr_0;
	u32 dma_frm_buf_base_addr_1;
	u32 dma_frm_buf_ceiling_addr_1;
	u32 raster_ctrl;
} reg_context;

static void lcd_context_save(void)
{
	if (lcd_revision == LCD_VERSION_2) {
		reg_context.clk_enable = lcdc_read(LCD_CLK_ENABLE_REG);
		reg_context.int_enable_set = lcdc_read(LCD_INT_ENABLE_SET_REG);
	}

	reg_context.ctrl = lcdc_read(LCD_CTRL_REG);
	reg_context.dma_ctrl = lcdc_read(LCD_DMA_CTRL_REG);
	reg_context.raster_timing_0 = lcdc_read(LCD_RASTER_TIMING_0_REG);
	reg_context.raster_timing_1 = lcdc_read(LCD_RASTER_TIMING_1_REG);
	reg_context.raster_timing_2 = lcdc_read(LCD_RASTER_TIMING_2_REG);
	reg_context.dma_frm_buf_base_addr_0 =
		lcdc_read(LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
	reg_context.dma_frm_buf_ceiling_addr_0 =
		lcdc_read(LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
	reg_context.dma_frm_buf_base_addr_1 =
		lcdc_read(LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
	reg_context.dma_frm_buf_ceiling_addr_1 =
		lcdc_read(LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
	reg_context.raster_ctrl = lcdc_read(LCD_RASTER_CTRL_REG);
	return;
}

static void lcd_context_restore(void)
{
	if (lcd_revision == LCD_VERSION_2) {
		lcdc_write(reg_context.clk_enable, LCD_CLK_ENABLE_REG);
		lcdc_write(reg_context.int_enable_set, LCD_INT_ENABLE_SET_REG);
	}

	lcdc_write(reg_context.ctrl, LCD_CTRL_REG);
	lcdc_write(reg_context.dma_ctrl, LCD_DMA_CTRL_REG);
	lcdc_write(reg_context.raster_timing_0, LCD_RASTER_TIMING_0_REG);
	lcdc_write(reg_context.raster_timing_1, LCD_RASTER_TIMING_1_REG);
	lcdc_write(reg_context.raster_timing_2, LCD_RASTER_TIMING_2_REG);
	lcdc_write(reg_context.dma_frm_buf_base_addr_0,
			LCD_DMA_FRM_BUF_BASE_ADDR_0_REG);
	lcdc_write(reg_context.dma_frm_buf_ceiling_addr_0,
			LCD_DMA_FRM_BUF_CEILING_ADDR_0_REG);
	lcdc_write(reg_context.dma_frm_buf_base_addr_1,
			LCD_DMA_FRM_BUF_BASE_ADDR_1_REG);
	lcdc_write(reg_context.dma_frm_buf_ceiling_addr_1,
			LCD_DMA_FRM_BUF_CEILING_ADDR_1_REG);
	lcdc_write(reg_context.raster_ctrl, LCD_RASTER_CTRL_REG);
	return;
}

static int fb_suspend(struct device *dev)
{
	struct fb_info *info = dev_get_drvdata(dev);
	struct da8xx_fb_par *par = info->par;

	console_lock();
	if (par->panel_power_ctrl)
		par->panel_power_ctrl(0);

	fb_set_suspend(info, 1);
	lcd_disable_raster(DA8XX_FRAME_WAIT);
	lcd_context_save();
	pm_runtime_put_sync(dev);
	console_unlock();

	return 0;
}
static int fb_resume(struct device *dev)
{
	struct fb_info *info = dev_get_drvdata(dev);
	struct da8xx_fb_par *par = info->par;

	console_lock();
	pm_runtime_get_sync(dev);
	lcd_context_restore();
	if (par->blank == FB_BLANK_UNBLANK) {
		lcd_enable_raster();

		if (par->panel_power_ctrl)
			par->panel_power_ctrl(1);
	}

	fb_set_suspend(info, 0);
	console_unlock();

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(fb_pm_ops, fb_suspend, fb_resume);

static struct platform_driver da8xx_fb_driver = {
	.probe = fb_probe,
	.remove = fb_remove,
	.driver = {
		   .name = DRIVER_NAME,
		   .pm	= &fb_pm_ops,
		   },
};
module_platform_driver(da8xx_fb_driver);

MODULE_DESCRIPTION("Framebuffer driver for TI da8xx/omap-l1xx");
MODULE_AUTHOR("Texas Instruments");
MODULE_LICENSE("GPL");