summaryrefslogtreecommitdiffstats
path: root/drivers/video/mxsfb.c
blob: 1b2c26d1658c65ed2fd73bb8a43462f537fe7f4a (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
/*
 * Copyright (C) 2010 Juergen Beisert, Pengutronix
 *
 * This code is based on:
 * Author: Vitaly Wool <vital@embeddedalley.com>
 *
 * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
 * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
 *
 * 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.
 */

#define DRIVER_NAME "mxsfb"

/**
 * @file
 * @brief LCDIF driver for i.MX23 and i.MX28
 *
 * The LCDIF support four modes of operation
 * - MPU interface (to drive smart displays) -> not supported yet
 * - VSYNC interface (like MPU interface plus Vsync) -> not supported yet
 * - Dotclock interface (to drive LC displays with RGB data and sync signals)
 * - DVI (to drive ITU-R BT656)  -> not supported yet
 *
 * This driver depends on a correct setup of the pins used for this purpose
 * (platform specific).
 *
 * For the developer: Don't forget to set the data bus width to the display
 * in the imx_fb_videomode structure. You will else end up with ugly colours.
 * If you fight against jitter you can vary the clock delay. This is a feature
 * of the i.MX28 and you can vary it between 2 ns ... 8 ns in 2 ns steps. Give
 * the required value in the imx_fb_videomode structure.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/of_device.h>
#include <video/of_display_timing.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/pinctrl/consumer.h>
#include <linux/fb.h>
#include <linux/regulator/consumer.h>
#include <video/videomode.h>

#define REG_SET	4
#define REG_CLR	8

#define LCDC_CTRL			0x00
#define LCDC_CTRL1			0x10
#define LCDC_V4_CTRL2			0x20
#define LCDC_V3_TRANSFER_COUNT		0x20
#define LCDC_V4_TRANSFER_COUNT		0x30
#define LCDC_V4_CUR_BUF			0x40
#define LCDC_V4_NEXT_BUF		0x50
#define LCDC_V3_CUR_BUF			0x30
#define LCDC_V3_NEXT_BUF		0x40
#define LCDC_TIMING			0x60
#define LCDC_VDCTRL0			0x70
#define LCDC_VDCTRL1			0x80
#define LCDC_VDCTRL2			0x90
#define LCDC_VDCTRL3			0xa0
#define LCDC_VDCTRL4			0xb0
#define LCDC_DVICTRL0			0xc0
#define LCDC_DVICTRL1			0xd0
#define LCDC_DVICTRL2			0xe0
#define LCDC_DVICTRL3			0xf0
#define LCDC_DVICTRL4			0x100
#define LCDC_V4_DATA			0x180
#define LCDC_V3_DATA			0x1b0
#define LCDC_V4_DEBUG0			0x1d0
#define LCDC_V3_DEBUG0			0x1f0

#define CTRL_SFTRST			(1 << 31)
#define CTRL_CLKGATE			(1 << 30)
#define CTRL_BYPASS_COUNT		(1 << 19)
#define CTRL_VSYNC_MODE			(1 << 18)
#define CTRL_DOTCLK_MODE		(1 << 17)
#define CTRL_DATA_SELECT		(1 << 16)
#define CTRL_SET_BUS_WIDTH(x)		(((x) & 0x3) << 10)
#define CTRL_GET_BUS_WIDTH(x)		(((x) >> 10) & 0x3)
#define CTRL_SET_WORD_LENGTH(x)		(((x) & 0x3) << 8)
#define CTRL_GET_WORD_LENGTH(x)		(((x) >> 8) & 0x3)
#define CTRL_MASTER			(1 << 5)
#define CTRL_DF16			(1 << 3)
#define CTRL_DF18			(1 << 2)
#define CTRL_DF24			(1 << 1)
#define CTRL_RUN			(1 << 0)

#define CTRL1_FIFO_CLEAR		(1 << 21)
#define CTRL1_SET_BYTE_PACKAGING(x)	(((x) & 0xf) << 16)
#define CTRL1_GET_BYTE_PACKAGING(x)	(((x) >> 16) & 0xf)

#define TRANSFER_COUNT_SET_VCOUNT(x)	(((x) & 0xffff) << 16)
#define TRANSFER_COUNT_GET_VCOUNT(x)	(((x) >> 16) & 0xffff)
#define TRANSFER_COUNT_SET_HCOUNT(x)	((x) & 0xffff)
#define TRANSFER_COUNT_GET_HCOUNT(x)	((x) & 0xffff)


#define VDCTRL0_ENABLE_PRESENT		(1 << 28)
#define VDCTRL0_VSYNC_ACT_HIGH		(1 << 27)
#define VDCTRL0_HSYNC_ACT_HIGH		(1 << 26)
#define VDCTRL0_DOTCLK_ACT_FALLING	(1 << 25)
#define VDCTRL0_ENABLE_ACT_HIGH		(1 << 24)
#define VDCTRL0_VSYNC_PERIOD_UNIT	(1 << 21)
#define VDCTRL0_VSYNC_PULSE_WIDTH_UNIT	(1 << 20)
#define VDCTRL0_HALF_LINE		(1 << 19)
#define VDCTRL0_HALF_LINE_MODE		(1 << 18)
#define VDCTRL0_SET_VSYNC_PULSE_WIDTH(x) ((x) & 0x3ffff)
#define VDCTRL0_GET_VSYNC_PULSE_WIDTH(x) ((x) & 0x3ffff)

#define VDCTRL2_SET_HSYNC_PERIOD(x)	((x) & 0x3ffff)
#define VDCTRL2_GET_HSYNC_PERIOD(x)	((x) & 0x3ffff)

#define VDCTRL3_MUX_SYNC_SIGNALS	(1 << 29)
#define VDCTRL3_VSYNC_ONLY		(1 << 28)
#define SET_HOR_WAIT_CNT(x)		(((x) & 0xfff) << 16)
#define GET_HOR_WAIT_CNT(x)		(((x) >> 16) & 0xfff)
#define SET_VERT_WAIT_CNT(x)		((x) & 0xffff)
#define GET_VERT_WAIT_CNT(x)		((x) & 0xffff)

#define VDCTRL4_SET_DOTCLK_DLY(x)	(((x) & 0x7) << 29) /* v4 only */
#define VDCTRL4_GET_DOTCLK_DLY(x)	(((x) >> 29) & 0x7) /* v4 only */
#define VDCTRL4_SYNC_SIGNALS_ON		(1 << 18)
#define SET_DOTCLK_H_VALID_DATA_CNT(x)	((x) & 0x3ffff)

#define DEBUG0_HSYNC			(1 < 26)
#define DEBUG0_VSYNC			(1 < 25)

#define MIN_XRES			120
#define MIN_YRES			120

#define RED 0
#define GREEN 1
#define BLUE 2
#define TRANSP 3

#define STMLCDIF_8BIT  1 /** pixel data bus to the display is of 8 bit width */
#define STMLCDIF_16BIT 0 /** pixel data bus to the display is of 16 bit width */
#define STMLCDIF_18BIT 2 /** pixel data bus to the display is of 18 bit width */
#define STMLCDIF_24BIT 3 /** pixel data bus to the display is of 24 bit width */

#define MXSFB_SYNC_DATA_ENABLE_HIGH_ACT	(1 << 6)
#define MXSFB_SYNC_DOTCLK_FALLING_ACT	(1 << 7) /* negtive edge sampling */

enum mxsfb_devtype {
	MXSFB_V3,
	MXSFB_V4,
};

/* CPU dependent register offsets */
struct mxsfb_devdata {
	unsigned transfer_count;
	unsigned cur_buf;
	unsigned next_buf;
	unsigned debug0;
	unsigned hs_wdth_mask;
	unsigned hs_wdth_shift;
	unsigned ipversion;
};

struct mxsfb_info {
	struct fb_info fb_info;
	struct platform_device *pdev;
	struct clk *clk;
	void __iomem *base;	/* registers */
	unsigned allocated_size;
	int enabled;
	unsigned ld_intf_width;
	unsigned dotclk_delay;
	const struct mxsfb_devdata *devdata;
	u32 sync;
	struct regulator *reg_lcd;
};

#define mxsfb_is_v3(host) (host->devdata->ipversion == 3)
#define mxsfb_is_v4(host) (host->devdata->ipversion == 4)

static const struct mxsfb_devdata mxsfb_devdata[] = {
	[MXSFB_V3] = {
		.transfer_count = LCDC_V3_TRANSFER_COUNT,
		.cur_buf = LCDC_V3_CUR_BUF,
		.next_buf = LCDC_V3_NEXT_BUF,
		.debug0 = LCDC_V3_DEBUG0,
		.hs_wdth_mask = 0xff,
		.hs_wdth_shift = 24,
		.ipversion = 3,
	},
	[MXSFB_V4] = {
		.transfer_count = LCDC_V4_TRANSFER_COUNT,
		.cur_buf = LCDC_V4_CUR_BUF,
		.next_buf = LCDC_V4_NEXT_BUF,
		.debug0 = LCDC_V4_DEBUG0,
		.hs_wdth_mask = 0x3fff,
		.hs_wdth_shift = 18,
		.ipversion = 4,
	},
};

#define to_imxfb_host(x) (container_of(x, struct mxsfb_info, fb_info))

/* mask and shift depends on architecture */
static inline u32 set_hsync_pulse_width(struct mxsfb_info *host, unsigned val)
{
	return (val & host->devdata->hs_wdth_mask) <<
		host->devdata->hs_wdth_shift;
}

static inline u32 get_hsync_pulse_width(struct mxsfb_info *host, unsigned val)
{
	return (val >> host->devdata->hs_wdth_shift) &
		host->devdata->hs_wdth_mask;
}

static const struct fb_bitfield def_rgb565[] = {
	[RED] = {
		.offset = 11,
		.length = 5,
	},
	[GREEN] = {
		.offset = 5,
		.length = 6,
	},
	[BLUE] = {
		.offset = 0,
		.length = 5,
	},
	[TRANSP] = {	/* no support for transparency */
		.length = 0,
	}
};

static const struct fb_bitfield def_rgb666[] = {
	[RED] = {
		.offset = 16,
		.length = 6,
	},
	[GREEN] = {
		.offset = 8,
		.length = 6,
	},
	[BLUE] = {
		.offset = 0,
		.length = 6,
	},
	[TRANSP] = {	/* no support for transparency */
		.length = 0,
	}
};

static const struct fb_bitfield def_rgb888[] = {
	[RED] = {
		.offset = 16,
		.length = 8,
	},
	[GREEN] = {
		.offset = 8,
		.length = 8,
	},
	[BLUE] = {
		.offset = 0,
		.length = 8,
	},
	[TRANSP] = {	/* no support for transparency */
		.length = 0,
	}
};

static inline unsigned chan_to_field(unsigned chan, struct fb_bitfield *bf)
{
	chan &= 0xffff;
	chan >>= 16 - bf->length;
	return chan << bf->offset;
}

static int mxsfb_check_var(struct fb_var_screeninfo *var,
		struct fb_info *fb_info)
{
	struct mxsfb_info *host = to_imxfb_host(fb_info);
	const struct fb_bitfield *rgb = NULL;

	if (var->xres < MIN_XRES)
		var->xres = MIN_XRES;
	if (var->yres < MIN_YRES)
		var->yres = MIN_YRES;

	var->xres_virtual = var->xres;

	var->yres_virtual = var->yres;

	switch (var->bits_per_pixel) {
	case 16:
		/* always expect RGB 565 */
		rgb = def_rgb565;
		break;
	case 32:
		switch (host->ld_intf_width) {
		case STMLCDIF_8BIT:
			pr_debug("Unsupported LCD bus width mapping\n");
			break;
		case STMLCDIF_16BIT:
		case STMLCDIF_18BIT:
			/* 24 bit to 18 bit mapping */
			rgb = def_rgb666;
			break;
		case STMLCDIF_24BIT:
			/* real 24 bit */
			rgb = def_rgb888;
			break;
		}
		break;
	default:
		pr_debug("Unsupported colour depth: %u\n", var->bits_per_pixel);
		return -EINVAL;
	}

	/*
	 * Copy the RGB parameters for this display
	 * from the machine specific parameters.
	 */
	var->red    = rgb[RED];
	var->green  = rgb[GREEN];
	var->blue   = rgb[BLUE];
	var->transp = rgb[TRANSP];

	return 0;
}

static void mxsfb_enable_controller(struct fb_info *fb_info)
{
	struct mxsfb_info *host = to_imxfb_host(fb_info);
	u32 reg;
	int ret;

	dev_dbg(&host->pdev->dev, "%s\n", __func__);

	if (host->reg_lcd) {
		ret = regulator_enable(host->reg_lcd);
		if (ret) {
			dev_err(&host->pdev->dev,
				"lcd regulator enable failed:	%d\n", ret);
			return;
		}
	}

	clk_prepare_enable(host->clk);
	clk_set_rate(host->clk, PICOS2KHZ(fb_info->var.pixclock) * 1000U);

	/* if it was disabled, re-enable the mode again */
	writel(CTRL_DOTCLK_MODE, host->base + LCDC_CTRL + REG_SET);

	/* enable the SYNC signals first, then the DMA engine */
	reg = readl(host->base + LCDC_VDCTRL4);
	reg |= VDCTRL4_SYNC_SIGNALS_ON;
	writel(reg, host->base + LCDC_VDCTRL4);

	writel(CTRL_RUN, host->base + LCDC_CTRL + REG_SET);

	host->enabled = 1;
}

static void mxsfb_disable_controller(struct fb_info *fb_info)
{
	struct mxsfb_info *host = to_imxfb_host(fb_info);
	unsigned loop;
	u32 reg;
	int ret;

	dev_dbg(&host->pdev->dev, "%s\n", __func__);

	/*
	 * Even if we disable the controller here, it will still continue
	 * until its FIFOs are running out of data
	 */
	writel(CTRL_DOTCLK_MODE, host->base + LCDC_CTRL + REG_CLR);

	loop = 1000;
	while (loop) {
		reg = readl(host->base + LCDC_CTRL);
		if (!(reg & CTRL_RUN))
			break;
		loop--;
	}

	reg = readl(host->base + LCDC_VDCTRL4);
	writel(reg & ~VDCTRL4_SYNC_SIGNALS_ON, host->base + LCDC_VDCTRL4);

	clk_disable_unprepare(host->clk);

	host->enabled = 0;

	if (host->reg_lcd) {
		ret = regulator_disable(host->reg_lcd);
		if (ret)
			dev_err(&host->pdev->dev,
				"lcd regulator disable failed: %d\n", ret);
	}
}

static int mxsfb_set_par(struct fb_info *fb_info)
{
	struct mxsfb_info *host = to_imxfb_host(fb_info);
	u32 ctrl, vdctrl0, vdctrl4;
	int line_size, fb_size;
	int reenable = 0;

	line_size =  fb_info->var.xres * (fb_info->var.bits_per_pixel >> 3);
	fb_size = fb_info->var.yres_virtual * line_size;

	if (fb_size > fb_info->fix.smem_len)
		return -ENOMEM;

	fb_info->fix.line_length = line_size;

	/*
	 * It seems, you can't re-program the controller if it is still running.
	 * This may lead into shifted pictures (FIFO issue?).
	 * So, first stop the controller and drain its FIFOs
	 */
	if (host->enabled) {
		reenable = 1;
		mxsfb_disable_controller(fb_info);
	}

	/* clear the FIFOs */
	writel(CTRL1_FIFO_CLEAR, host->base + LCDC_CTRL1 + REG_SET);

	ctrl = CTRL_BYPASS_COUNT | CTRL_MASTER |
		CTRL_SET_BUS_WIDTH(host->ld_intf_width);

	switch (fb_info->var.bits_per_pixel) {
	case 16:
		dev_dbg(&host->pdev->dev, "Setting up RGB565 mode\n");
		ctrl |= CTRL_SET_WORD_LENGTH(0);
		writel(CTRL1_SET_BYTE_PACKAGING(0xf), host->base + LCDC_CTRL1);
		break;
	case 32:
		dev_dbg(&host->pdev->dev, "Setting up RGB888/666 mode\n");
		ctrl |= CTRL_SET_WORD_LENGTH(3);
		switch (host->ld_intf_width) {
		case STMLCDIF_8BIT:
			dev_dbg(&host->pdev->dev,
					"Unsupported LCD bus width mapping\n");
			return -EINVAL;
		case STMLCDIF_16BIT:
		case STMLCDIF_18BIT:
			/* 24 bit to 18 bit mapping */
			ctrl |= CTRL_DF24; /* ignore the upper 2 bits in
					    *  each colour component
					    */
			break;
		case STMLCDIF_24BIT:
			/* real 24 bit */
			break;
		}
		/* do not use packed pixels = one pixel per word instead */
		writel(CTRL1_SET_BYTE_PACKAGING(0x7), host->base + LCDC_CTRL1);
		break;
	default:
		dev_dbg(&host->pdev->dev, "Unhandled color depth of %u\n",
				fb_info->var.bits_per_pixel);
		return -EINVAL;
	}

	writel(ctrl, host->base + LCDC_CTRL);

	writel(TRANSFER_COUNT_SET_VCOUNT(fb_info->var.yres) |
			TRANSFER_COUNT_SET_HCOUNT(fb_info->var.xres),
			host->base + host->devdata->transfer_count);

	vdctrl0 = VDCTRL0_ENABLE_PRESENT |	/* always in DOTCLOCK mode */
		VDCTRL0_VSYNC_PERIOD_UNIT |
		VDCTRL0_VSYNC_PULSE_WIDTH_UNIT |
		VDCTRL0_SET_VSYNC_PULSE_WIDTH(fb_info->var.vsync_len);
	if (fb_info->var.sync & FB_SYNC_HOR_HIGH_ACT)
		vdctrl0 |= VDCTRL0_HSYNC_ACT_HIGH;
	if (fb_info->var.sync & FB_SYNC_VERT_HIGH_ACT)
		vdctrl0 |= VDCTRL0_VSYNC_ACT_HIGH;
	if (host->sync & MXSFB_SYNC_DATA_ENABLE_HIGH_ACT)
		vdctrl0 |= VDCTRL0_ENABLE_ACT_HIGH;
	if (host->sync & MXSFB_SYNC_DOTCLK_FALLING_ACT)
		vdctrl0 |= VDCTRL0_DOTCLK_ACT_FALLING;

	writel(vdctrl0, host->base + LCDC_VDCTRL0);

	/* frame length in lines */
	writel(fb_info->var.upper_margin + fb_info->var.vsync_len +
		fb_info->var.lower_margin + fb_info->var.yres,
		host->base + LCDC_VDCTRL1);

	/* line length in units of clocks or pixels */
	writel(set_hsync_pulse_width(host, fb_info->var.hsync_len) |
		VDCTRL2_SET_HSYNC_PERIOD(fb_info->var.left_margin +
		fb_info->var.hsync_len + fb_info->var.right_margin +
		fb_info->var.xres),
		host->base + LCDC_VDCTRL2);

	writel(SET_HOR_WAIT_CNT(fb_info->var.left_margin +
		fb_info->var.hsync_len) |
		SET_VERT_WAIT_CNT(fb_info->var.upper_margin +
			fb_info->var.vsync_len),
		host->base + LCDC_VDCTRL3);

	vdctrl4 = SET_DOTCLK_H_VALID_DATA_CNT(fb_info->var.xres);
	if (mxsfb_is_v4(host))
		vdctrl4 |= VDCTRL4_SET_DOTCLK_DLY(host->dotclk_delay);
	writel(vdctrl4, host->base + LCDC_VDCTRL4);

	writel(fb_info->fix.smem_start +
			fb_info->fix.line_length * fb_info->var.yoffset,
			host->base + host->devdata->next_buf);

	if (reenable)
		mxsfb_enable_controller(fb_info);

	return 0;
}

static int mxsfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
		u_int transp, struct fb_info *fb_info)
{
	unsigned int val;
	int ret = -EINVAL;

	/*
	 * If greyscale is true, then we convert the RGB value
	 * to greyscale no matter what visual we are using.
	 */
	if (fb_info->var.grayscale)
		red = green = blue = (19595 * red + 38470 * green +
					7471 * blue) >> 16;

	switch (fb_info->fix.visual) {
	case FB_VISUAL_TRUECOLOR:
		/*
		 * 12 or 16-bit True Colour.  We encode the RGB value
		 * according to the RGB bitfield information.
		 */
		if (regno < 16) {
			u32 *pal = fb_info->pseudo_palette;

			val  = chan_to_field(red, &fb_info->var.red);
			val |= chan_to_field(green, &fb_info->var.green);
			val |= chan_to_field(blue, &fb_info->var.blue);

			pal[regno] = val;
			ret = 0;
		}
		break;

	case FB_VISUAL_STATIC_PSEUDOCOLOR:
	case FB_VISUAL_PSEUDOCOLOR:
		break;
	}

	return ret;
}

static int mxsfb_blank(int blank, struct fb_info *fb_info)
{
	struct mxsfb_info *host = to_imxfb_host(fb_info);

	switch (blank) {
	case FB_BLANK_POWERDOWN:
	case FB_BLANK_VSYNC_SUSPEND:
	case FB_BLANK_HSYNC_SUSPEND:
	case FB_BLANK_NORMAL:
		if (host->enabled)
			mxsfb_disable_controller(fb_info);
		break;

	case FB_BLANK_UNBLANK:
		if (!host->enabled)
			mxsfb_enable_controller(fb_info);
		break;
	}
	return 0;
}

static int mxsfb_pan_display(struct fb_var_screeninfo *var,
		struct fb_info *fb_info)
{
	struct mxsfb_info *host = to_imxfb_host(fb_info);
	unsigned offset;

	if (var->xoffset != 0)
		return -EINVAL;

	offset = fb_info->fix.line_length * var->yoffset;

	/* update on next VSYNC */
	writel(fb_info->fix.smem_start + offset,
			host->base + host->devdata->next_buf);

	return 0;
}

static struct fb_ops mxsfb_ops = {
	.owner = THIS_MODULE,
	.fb_check_var = mxsfb_check_var,
	.fb_set_par = mxsfb_set_par,
	.fb_setcolreg = mxsfb_setcolreg,
	.fb_blank = mxsfb_blank,
	.fb_pan_display = mxsfb_pan_display,
	.fb_fillrect = cfb_fillrect,
	.fb_copyarea = cfb_copyarea,
	.fb_imageblit = cfb_imageblit,
};

static int mxsfb_restore_mode(struct mxsfb_info *host)
{
	struct fb_info *fb_info = &host->fb_info;
	unsigned line_count;
	unsigned period;
	unsigned long pa, fbsize;
	int bits_per_pixel, ofs;
	u32 transfer_count, vdctrl0, vdctrl2, vdctrl3, vdctrl4, ctrl;
	struct fb_videomode vmode;

	/* Only restore the mode when the controller is running */
	ctrl = readl(host->base + LCDC_CTRL);
	if (!(ctrl & CTRL_RUN))
		return -EINVAL;

	vdctrl0 = readl(host->base + LCDC_VDCTRL0);
	vdctrl2 = readl(host->base + LCDC_VDCTRL2);
	vdctrl3 = readl(host->base + LCDC_VDCTRL3);
	vdctrl4 = readl(host->base + LCDC_VDCTRL4);

	transfer_count = readl(host->base + host->devdata->transfer_count);

	vmode.xres = TRANSFER_COUNT_GET_HCOUNT(transfer_count);
	vmode.yres = TRANSFER_COUNT_GET_VCOUNT(transfer_count);

	switch (CTRL_GET_WORD_LENGTH(ctrl)) {
	case 0:
		bits_per_pixel = 16;
		break;
	case 3:
		bits_per_pixel = 32;
	case 1:
	default:
		return -EINVAL;
	}

	fb_info->var.bits_per_pixel = bits_per_pixel;

	vmode.pixclock = KHZ2PICOS(clk_get_rate(host->clk) / 1000U);
	vmode.hsync_len = get_hsync_pulse_width(host, vdctrl2);
	vmode.left_margin = GET_HOR_WAIT_CNT(vdctrl3) - vmode.hsync_len;
	vmode.right_margin = VDCTRL2_GET_HSYNC_PERIOD(vdctrl2) - vmode.hsync_len -
		vmode.left_margin - vmode.xres;
	vmode.vsync_len = VDCTRL0_GET_VSYNC_PULSE_WIDTH(vdctrl0);
	period = readl(host->base + LCDC_VDCTRL1);
	vmode.upper_margin = GET_VERT_WAIT_CNT(vdctrl3) - vmode.vsync_len;
	vmode.lower_margin = period - vmode.vsync_len - vmode.upper_margin - vmode.yres;

	vmode.vmode = FB_VMODE_NONINTERLACED;

	vmode.sync = 0;
	if (vdctrl0 & VDCTRL0_HSYNC_ACT_HIGH)
		vmode.sync |= FB_SYNC_HOR_HIGH_ACT;
	if (vdctrl0 & VDCTRL0_VSYNC_ACT_HIGH)
		vmode.sync |= FB_SYNC_VERT_HIGH_ACT;

	pr_debug("Reconstructed video mode:\n");
	pr_debug("%dx%d, hsync: %u left: %u, right: %u, vsync: %u, upper: %u, lower: %u\n",
			vmode.xres, vmode.yres,
			vmode.hsync_len, vmode.left_margin, vmode.right_margin,
			vmode.vsync_len, vmode.upper_margin, vmode.lower_margin);
	pr_debug("pixclk: %ldkHz\n", PICOS2KHZ(vmode.pixclock));

	fb_add_videomode(&vmode, &fb_info->modelist);

	host->ld_intf_width = CTRL_GET_BUS_WIDTH(ctrl);
	host->dotclk_delay = VDCTRL4_GET_DOTCLK_DLY(vdctrl4);

	fb_info->fix.line_length = vmode.xres * (bits_per_pixel >> 3);

	pa = readl(host->base + host->devdata->cur_buf);
	fbsize = fb_info->fix.line_length * vmode.yres;
	if (pa < fb_info->fix.smem_start)
		return -EINVAL;
	if (pa + fbsize > fb_info->fix.smem_start + fb_info->fix.smem_len)
		return -EINVAL;
	ofs = pa - fb_info->fix.smem_start;
	if (ofs) {
		memmove(fb_info->screen_base, fb_info->screen_base + ofs, fbsize);
		writel(fb_info->fix.smem_start, host->base + host->devdata->next_buf);
	}

	line_count = fb_info->fix.smem_len / fb_info->fix.line_length;
	fb_info->fix.ypanstep = 1;

	clk_prepare_enable(host->clk);
	host->enabled = 1;

	return 0;
}

static int mxsfb_init_fbinfo_dt(struct mxsfb_info *host)
{
	struct fb_info *fb_info = &host->fb_info;
	struct fb_var_screeninfo *var = &fb_info->var;
	struct device *dev = &host->pdev->dev;
	struct device_node *np = host->pdev->dev.of_node;
	struct device_node *display_np;
	struct device_node *timings_np;
	struct display_timings *timings;
	u32 width;
	int i;
	int ret = 0;

	display_np = of_parse_phandle(np, "display", 0);
	if (!display_np) {
		dev_err(dev, "failed to find display phandle\n");
		return -ENOENT;
	}

	ret = of_property_read_u32(display_np, "bus-width", &width);
	if (ret < 0) {
		dev_err(dev, "failed to get property bus-width\n");
		goto put_display_node;
	}

	switch (width) {
	case 8:
		host->ld_intf_width = STMLCDIF_8BIT;
		break;
	case 16:
		host->ld_intf_width = STMLCDIF_16BIT;
		break;
	case 18:
		host->ld_intf_width = STMLCDIF_18BIT;
		break;
	case 24:
		host->ld_intf_width = STMLCDIF_24BIT;
		break;
	default:
		dev_err(dev, "invalid bus-width value\n");
		ret = -EINVAL;
		goto put_display_node;
	}

	ret = of_property_read_u32(display_np, "bits-per-pixel",
				   &var->bits_per_pixel);
	if (ret < 0) {
		dev_err(dev, "failed to get property bits-per-pixel\n");
		goto put_display_node;
	}

	timings = of_get_display_timings(display_np);
	if (!timings) {
		dev_err(dev, "failed to get display timings\n");
		ret = -ENOENT;
		goto put_display_node;
	}

	timings_np = of_find_node_by_name(display_np,
					  "display-timings");
	if (!timings_np) {
		dev_err(dev, "failed to find display-timings node\n");
		ret = -ENOENT;
		goto put_display_node;
	}

	for (i = 0; i < of_get_child_count(timings_np); i++) {
		struct videomode vm;
		struct fb_videomode fb_vm;

		ret = videomode_from_timing(timings, &vm, i);
		if (ret < 0)
			goto put_timings_node;
		ret = fb_videomode_from_videomode(&vm, &fb_vm);
		if (ret < 0)
			goto put_timings_node;

		if (vm.data_flags & DISPLAY_FLAGS_DE_HIGH)
			host->sync |= MXSFB_SYNC_DATA_ENABLE_HIGH_ACT;
		if (vm.data_flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
			host->sync |= MXSFB_SYNC_DOTCLK_FALLING_ACT;
		fb_add_videomode(&fb_vm, &fb_info->modelist);
	}

put_timings_node:
	of_node_put(timings_np);
put_display_node:
	of_node_put(display_np);
	return ret;
}

static int mxsfb_init_fbinfo(struct mxsfb_info *host)
{
	struct fb_info *fb_info = &host->fb_info;
	struct fb_var_screeninfo *var = &fb_info->var;
	dma_addr_t fb_phys;
	void *fb_virt;
	unsigned fb_size;
	int ret;

	fb_info->fbops = &mxsfb_ops;
	fb_info->flags = FBINFO_FLAG_DEFAULT | FBINFO_READS_FAST;
	strlcpy(fb_info->fix.id, "mxs", sizeof(fb_info->fix.id));
	fb_info->fix.type = FB_TYPE_PACKED_PIXELS;
	fb_info->fix.ypanstep = 1;
	fb_info->fix.visual = FB_VISUAL_TRUECOLOR,
	fb_info->fix.accel = FB_ACCEL_NONE;

	ret = mxsfb_init_fbinfo_dt(host);
	if (ret)
		return ret;

	var->nonstd = 0;
	var->activate = FB_ACTIVATE_NOW;
	var->accel_flags = 0;
	var->vmode = FB_VMODE_NONINTERLACED;

	/* Memory allocation for framebuffer */
	fb_size = SZ_2M;
	fb_virt = alloc_pages_exact(fb_size, GFP_DMA);
	if (!fb_virt)
		return -ENOMEM;

	fb_phys = virt_to_phys(fb_virt);

	fb_info->fix.smem_start = fb_phys;
	fb_info->screen_base = fb_virt;
	fb_info->screen_size = fb_info->fix.smem_len = fb_size;

	if (mxsfb_restore_mode(host))
		memset(fb_virt, 0, fb_size);

	return 0;
}

static void mxsfb_free_videomem(struct mxsfb_info *host)
{
	struct fb_info *fb_info = &host->fb_info;

	free_pages_exact(fb_info->screen_base, fb_info->fix.smem_len);
}

static struct platform_device_id mxsfb_devtype[] = {
	{
		.name = "imx23-fb",
		.driver_data = MXSFB_V3,
	}, {
		.name = "imx28-fb",
		.driver_data = MXSFB_V4,
	}, {
		/* sentinel */
	}
};
MODULE_DEVICE_TABLE(platform, mxsfb_devtype);

static const struct of_device_id mxsfb_dt_ids[] = {
	{ .compatible = "fsl,imx23-lcdif", .data = &mxsfb_devtype[0], },
	{ .compatible = "fsl,imx28-lcdif", .data = &mxsfb_devtype[1], },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mxsfb_dt_ids);

static int mxsfb_probe(struct platform_device *pdev)
{
	const struct of_device_id *of_id =
			of_match_device(mxsfb_dt_ids, &pdev->dev);
	struct resource *res;
	struct mxsfb_info *host;
	struct fb_info *fb_info;
	struct fb_modelist *modelist;
	struct pinctrl *pinctrl;
	int ret;

	if (of_id)
		pdev->id_entry = of_id->data;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(&pdev->dev, "Cannot get memory IO resource\n");
		return -ENODEV;
	}

	fb_info = framebuffer_alloc(sizeof(struct mxsfb_info), &pdev->dev);
	if (!fb_info) {
		dev_err(&pdev->dev, "Failed to allocate fbdev\n");
		return -ENOMEM;
	}

	host = to_imxfb_host(fb_info);

	host->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(host->base)) {
		dev_err(&pdev->dev, "ioremap failed\n");
		ret = PTR_ERR(host->base);
		goto fb_release;
	}

	host->pdev = pdev;
	platform_set_drvdata(pdev, host);

	host->devdata = &mxsfb_devdata[pdev->id_entry->driver_data];

	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
	if (IS_ERR(pinctrl)) {
		ret = PTR_ERR(pinctrl);
		goto fb_release;
	}

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

	host->reg_lcd = devm_regulator_get(&pdev->dev, "lcd");
	if (IS_ERR(host->reg_lcd))
		host->reg_lcd = NULL;

	fb_info->pseudo_palette = devm_kzalloc(&pdev->dev, sizeof(u32) * 16,
					       GFP_KERNEL);
	if (!fb_info->pseudo_palette) {
		ret = -ENOMEM;
		goto fb_release;
	}

	INIT_LIST_HEAD(&fb_info->modelist);

	ret = mxsfb_init_fbinfo(host);
	if (ret != 0)
		goto fb_release;

	modelist = list_first_entry(&fb_info->modelist,
			struct fb_modelist, list);
	fb_videomode_to_var(&fb_info->var, &modelist->mode);

	/* init the color fields */
	mxsfb_check_var(&fb_info->var, fb_info);

	platform_set_drvdata(pdev, fb_info);

	ret = register_framebuffer(fb_info);
	if (ret != 0) {
		dev_err(&pdev->dev,"Failed to register framebuffer\n");
		goto fb_destroy;
	}

	if (!host->enabled) {
		writel(0, host->base + LCDC_CTRL);
		mxsfb_set_par(fb_info);
		mxsfb_enable_controller(fb_info);
	}

	dev_info(&pdev->dev, "initialized\n");

	return 0;

fb_destroy:
	if (host->enabled)
		clk_disable_unprepare(host->clk);
	fb_destroy_modelist(&fb_info->modelist);
fb_release:
	framebuffer_release(fb_info);

	return ret;
}

static int mxsfb_remove(struct platform_device *pdev)
{
	struct fb_info *fb_info = platform_get_drvdata(pdev);
	struct mxsfb_info *host = to_imxfb_host(fb_info);

	if (host->enabled)
		mxsfb_disable_controller(fb_info);

	unregister_framebuffer(fb_info);
	mxsfb_free_videomem(host);

	framebuffer_release(fb_info);

	platform_set_drvdata(pdev, NULL);

	return 0;
}

static void mxsfb_shutdown(struct platform_device *pdev)
{
	struct fb_info *fb_info = platform_get_drvdata(pdev);
	struct mxsfb_info *host = to_imxfb_host(fb_info);

	/*
	 * Force stop the LCD controller as keeping it running during reboot
	 * might interfere with the BootROM's boot mode pads sampling.
	 */
	writel(CTRL_RUN, host->base + LCDC_CTRL + REG_CLR);
}

static struct platform_driver mxsfb_driver = {
	.probe = mxsfb_probe,
	.remove = mxsfb_remove,
	.shutdown = mxsfb_shutdown,
	.id_table = mxsfb_devtype,
	.driver = {
		   .name = DRIVER_NAME,
		   .of_match_table = mxsfb_dt_ids,
	},
};

module_platform_driver(mxsfb_driver);

MODULE_DESCRIPTION("Freescale mxs framebuffer driver");
MODULE_AUTHOR("Sascha Hauer, Pengutronix");
MODULE_LICENSE("GPL");
OpenPOWER on IntegriCloud