aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/video/atmel_lcdfb.c
blob: dda920623c6a45b96886e5729419f9dc1c1d7534 (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
/*
 *  Driver for AT91/AT32 LCD Controller
 *
 *  Copyright (C) 2007 Atmel Corporation
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive for
 * more details.
 */

#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/backlight.h>
#include <linux/gfp.h>

#include <mach/board.h>
#include <mach/cpu.h>
#include <asm/gpio.h>

#include <video/atmel_lcdc.h>

#define lcdc_readl(sinfo, reg)		__raw_readl((sinfo)->mmio+(reg))
#define lcdc_writel(sinfo, reg, val)	__raw_writel((val), (sinfo)->mmio+(reg))

/* configurable parameters */
#define ATMEL_LCDC_CVAL_DEFAULT		0xc8
#define ATMEL_LCDC_DMA_BURST_LEN	8	/* words */
#define ATMEL_LCDC_FIFO_SIZE		512	/* words */

#if defined(CONFIG_ARCH_AT91)
#define	ATMEL_LCDFB_FBINFO_DEFAULT	(FBINFO_DEFAULT \
					 | FBINFO_PARTIAL_PAN_OK \
					 | FBINFO_HWACCEL_YPAN)

static inline void atmel_lcdfb_update_dma2d(struct atmel_lcdfb_info *sinfo,
					struct fb_var_screeninfo *var)
{

}
#elif defined(CONFIG_AVR32)
#define	ATMEL_LCDFB_FBINFO_DEFAULT	(FBINFO_DEFAULT \
					| FBINFO_PARTIAL_PAN_OK \
					| FBINFO_HWACCEL_XPAN \
					| FBINFO_HWACCEL_YPAN)

static void atmel_lcdfb_update_dma2d(struct atmel_lcdfb_info *sinfo,
				     struct fb_var_screeninfo *var)
{
	u32 dma2dcfg;
	u32 pixeloff;

	pixeloff = (var->xoffset * var->bits_per_pixel) & 0x1f;

	dma2dcfg = ((var->xres_virtual - var->xres) * var->bits_per_pixel) / 8;
	dma2dcfg |= pixeloff << ATMEL_LCDC_PIXELOFF_OFFSET;
	lcdc_writel(sinfo, ATMEL_LCDC_DMA2DCFG, dma2dcfg);

	/* Update configuration */
	lcdc_writel(sinfo, ATMEL_LCDC_DMACON,
		    lcdc_readl(sinfo, ATMEL_LCDC_DMACON)
		    | ATMEL_LCDC_DMAUPDT);
}
#endif

static u32 contrast_ctr = ATMEL_LCDC_PS_DIV8
		| ATMEL_LCDC_POL_POSITIVE
		| ATMEL_LCDC_ENA_PWMENABLE;

#ifdef CONFIG_BACKLIGHT_ATMEL_LCDC

/* some bl->props field just changed */
static int atmel_bl_update_status(struct backlight_device *bl)
{
	struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
	int			power = sinfo->bl_power;
	int			brightness = bl->props.brightness;

	/* REVISIT there may be a meaningful difference between
	 * fb_blank and power ... there seem to be some cases
	 * this doesn't handle correctly.
	 */
	if (bl->props.fb_blank != sinfo->bl_power)
		power = bl->props.fb_blank;
	else if (bl->props.power != sinfo->bl_power)
		power = bl->props.power;

	if (brightness < 0 && power == FB_BLANK_UNBLANK)
		brightness = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
	else if (power != FB_BLANK_UNBLANK)
		brightness = 0;

	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, brightness);
	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR,
			brightness ? contrast_ctr : 0);

	bl->props.fb_blank = bl->props.power = sinfo->bl_power = power;

	return 0;
}

static int atmel_bl_get_brightness(struct backlight_device *bl)
{
	struct atmel_lcdfb_info *sinfo = bl_get_data(bl);

	return lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
}

static const struct backlight_ops atmel_lcdc_bl_ops = {
	.update_status = atmel_bl_update_status,
	.get_brightness = atmel_bl_get_brightness,
};

static void init_backlight(struct atmel_lcdfb_info *sinfo)
{
	struct backlight_properties props;
	struct backlight_device	*bl;

	sinfo->bl_power = FB_BLANK_UNBLANK;

	if (sinfo->backlight)
		return;

	memset(&props, 0, sizeof(struct backlight_properties));
	props.type = BACKLIGHT_RAW;
	props.max_brightness = 0xff;
	bl = backlight_device_register("backlight", &sinfo->pdev->dev, sinfo,
				       &atmel_lcdc_bl_ops, &props);
	if (IS_ERR(bl)) {
		dev_err(&sinfo->pdev->dev, "error %ld on backlight register\n",
				PTR_ERR(bl));
		return;
	}
	sinfo->backlight = bl;

	bl->props.power = FB_BLANK_UNBLANK;
	bl->props.fb_blank = FB_BLANK_UNBLANK;
	bl->props.brightness = atmel_bl_get_brightness(bl);
}

static void exit_backlight(struct atmel_lcdfb_info *sinfo)
{
	if (sinfo->backlight)
		backlight_device_unregister(sinfo->backlight);
}

#else

static void init_backlight(struct atmel_lcdfb_info *sinfo)
{
	dev_warn(&sinfo->pdev->dev, "backlight control is not available\n");
}

static void exit_backlight(struct atmel_lcdfb_info *sinfo)
{
}

#endif

static void init_contrast(struct atmel_lcdfb_info *sinfo)
{
	/* contrast pwm can be 'inverted' */
	if (sinfo->lcdcon_pol_negative)
			contrast_ctr &= ~(ATMEL_LCDC_POL_POSITIVE);

	/* have some default contrast/backlight settings */
	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, ATMEL_LCDC_CVAL_DEFAULT);

	if (sinfo->lcdcon_is_backlight)
		init_backlight(sinfo);
}


static struct fb_fix_screeninfo atmel_lcdfb_fix __initdata = {
	.type		= FB_TYPE_PACKED_PIXELS,
	.visual		= FB_VISUAL_TRUECOLOR,
	.xpanstep	= 0,
	.ypanstep	= 1,
	.ywrapstep	= 0,
	.accel		= FB_ACCEL_NONE,
};

static unsigned long compute_hozval(unsigned long xres, unsigned long lcdcon2)
{
	unsigned long value;

	if (!(cpu_is_at91sam9261() || cpu_is_at91sam9g10()
		|| cpu_is_at32ap7000()))
		return xres;

	value = xres;
	if ((lcdcon2 & ATMEL_LCDC_DISTYPE) != ATMEL_LCDC_DISTYPE_TFT) {
		/* STN display */
		if ((lcdcon2 & ATMEL_LCDC_DISTYPE) == ATMEL_LCDC_DISTYPE_STNCOLOR) {
			value *= 3;
		}
		if ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_4
		   || ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_8
		      && (lcdcon2 & ATMEL_LCDC_SCANMOD) == ATMEL_LCDC_SCANMOD_DUAL ))
			value = DIV_ROUND_UP(value, 4);
		else
			value = DIV_ROUND_UP(value, 8);
	}

	return value;
}

static void atmel_lcdfb_stop_nowait(struct atmel_lcdfb_info *sinfo)
{
	/* Turn off the LCD controller and the DMA controller */
	lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
			sinfo->guard_time << ATMEL_LCDC_GUARDT_OFFSET);

	/* Wait for the LCDC core to become idle */
	while (lcdc_readl(sinfo, ATMEL_LCDC_PWRCON) & ATMEL_LCDC_BUSY)
		msleep(10);

	lcdc_writel(sinfo, ATMEL_LCDC_DMACON, 0);
}

static void atmel_lcdfb_stop(struct atmel_lcdfb_info *sinfo)
{
	atmel_lcdfb_stop_nowait(sinfo);

	/* Wait for DMA engine to become idle... */
	while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
		msleep(10);
}

static void atmel_lcdfb_start(struct atmel_lcdfb_info *sinfo)
{
	lcdc_writel(sinfo, ATMEL_LCDC_DMACON, sinfo->default_dmacon);
	lcdc_writel(sinfo, ATMEL_LCDC_PWRCON,
		(sinfo->guard_time << ATMEL_LCDC_GUARDT_OFFSET)
		| ATMEL_LCDC_PWR);
}

static void atmel_lcdfb_update_dma(struct fb_info *info,
			       struct fb_var_screeninfo *var)
{
	struct atmel_lcdfb_info *sinfo = info->par;
	struct fb_fix_screeninfo *fix = &info->fix;
	unsigned long dma_addr;

	dma_addr = (fix->smem_start + var->yoffset * fix->line_length
		    + var->xoffset * var->bits_per_pixel / 8);

	dma_addr &= ~3UL;

	/* Set framebuffer DMA base address and pixel offset */
	lcdc_writel(sinfo, ATMEL_LCDC_DMABADDR1, dma_addr);

	atmel_lcdfb_update_dma2d(sinfo, var);
}

static inline void atmel_lcdfb_free_video_memory(struct atmel_lcdfb_info *sinfo)
{
	struct fb_info *info = sinfo->info;

	dma_free_writecombine(info->device, info->fix.smem_len,
				info->screen_base, info->fix.smem_start);
}

/**
 *	atmel_lcdfb_alloc_video_memory - Allocate framebuffer memory
 *	@sinfo: the frame buffer to allocate memory for
 * 	
 * 	This function is called only from the atmel_lcdfb_probe()
 * 	so no locking by fb_info->mm_lock around smem_len setting is needed.
 */
static int atmel_lcdfb_alloc_video_memory(struct atmel_lcdfb_info *sinfo)
{
	struct fb_info *info = sinfo->info;
	struct fb_var_screeninfo *var = &info->var;
	unsigned int smem_len;

	smem_len = (var->xres_virtual * var->yres_virtual
		    * ((var->bits_per_pixel + 7) / 8));
	info->fix.smem_len = max(smem_len, sinfo->smem_len);

	info->screen_base = dma_alloc_writecombine(info->device, info->fix.smem_len,
					(dma_addr_t *)&info->fix.smem_start, GFP_KERNEL);

	if (!info->screen_base) {
		return -ENOMEM;
	}

	memset(info->screen_base, 0, info->fix.smem_len);

	return 0;
}

static const struct fb_videomode *atmel_lcdfb_choose_mode(struct fb_var_screeninfo *var,
						     struct fb_info *info)
{
	struct fb_videomode varfbmode;
	const struct fb_videomode *fbmode = NULL;

	fb_var_to_videomode(&varfbmode, var);
	fbmode = fb_find_nearest_mode(&varfbmode, &info->modelist);
	if (fbmode)
		fb_videomode_to_var(var, fbmode);
	return fbmode;
}


/**
 *      atmel_lcdfb_check_var - Validates a var passed in.
 *      @var: frame buffer variable screen structure
 *      @info: frame buffer structure that represents a single frame buffer
 *
 *	Checks to see if the hardware supports the state requested by
 *	var passed in. This function does not alter the hardware
 *	state!!!  This means the data stored in struct fb_info and
 *	struct atmel_lcdfb_info do not change. This includes the var
 *	inside of struct fb_info.  Do NOT change these. This function
 *	can be called on its own if we intent to only test a mode and
 *	not actually set it. The stuff in modedb.c is a example of
 *	this. If the var passed in is slightly off by what the
 *	hardware can support then we alter the var PASSED in to what
 *	we can do. If the hardware doesn't support mode change a
 *	-EINVAL will be returned by the upper layers. You don't need
 *	to implement this function then. If you hardware doesn't
 *	support changing the resolution then this function is not
 *	needed. In this case the driver would just provide a var that
 *	represents the static state the screen is in.
 *
 *	Returns negative errno on error, or zero on success.
 */
static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var,
			     struct fb_info *info)
{
	struct device *dev = info->device;
	struct atmel_lcdfb_info *sinfo = info->par;
	unsigned long clk_value_khz;

	clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;

	dev_dbg(dev, "%s:\n", __func__);

	if (!(var->pixclock && var->bits_per_pixel)) {
		/* choose a suitable mode if possible */
		if (!atmel_lcdfb_choose_mode(var, info)) {
			dev_err(dev, "needed value not specified\n");
			return -EINVAL;
		}
	}

	dev_dbg(dev, "  resolution: %ux%u\n", var->xres, var->yres);
	dev_dbg(dev, "  pixclk:     %lu KHz\n", PICOS2KHZ(var->pixclock));
	dev_dbg(dev, "  bpp:        %u\n", var->bits_per_pixel);
	dev_dbg(dev, "  clk:        %lu KHz\n", clk_value_khz);

	if (PICOS2KHZ(var->pixclock) > clk_value_khz) {
		dev_err(dev, "%lu KHz pixel clock is too fast\n", PICOS2KHZ(var->pixclock));
		return -EINVAL;
	}

	/* Do not allow to have real resoulution larger than virtual */
	if (var->xres > var->xres_virtual)
		var->xres_virtual = var->xres;

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

	/* Force same alignment for each line */
	var->xres = (var->xres + 3) & ~3UL;
	var->xres_virtual = (var->xres_virtual + 3) & ~3UL;

	var->red.msb_right = var->green.msb_right = var->blue.msb_right = 0;
	var->transp.msb_right = 0;
	var->transp.offset = var->transp.length = 0;
	var->xoffset = var->yoffset = 0;

	if (info->fix.smem_len) {
		unsigned int smem_len = (var->xres_virtual * var->yres_virtual
					 * ((var->bits_per_pixel + 7) / 8));
		if (smem_len > info->fix.smem_len)
			return -EINVAL;
	}

	/* Saturate vertical and horizontal timings at maximum values */
	var->vsync_len = min_t(u32, var->vsync_len,
			(ATMEL_LCDC_VPW >> ATMEL_LCDC_VPW_OFFSET) + 1);
	var->upper_margin = min_t(u32, var->upper_margin,
			ATMEL_LCDC_VBP >> ATMEL_LCDC_VBP_OFFSET);
	var->lower_margin = min_t(u32, var->lower_margin,
			ATMEL_LCDC_VFP);
	var->right_margin = min_t(u32, var->right_margin,
			(ATMEL_LCDC_HFP >> ATMEL_LCDC_HFP_OFFSET) + 1);
	var->hsync_len = min_t(u32, var->hsync_len,
			(ATMEL_LCDC_HPW >> ATMEL_LCDC_HPW_OFFSET) + 1);
	var->left_margin = min_t(u32, var->left_margin,
			ATMEL_LCDC_HBP + 1);

	/* Some parameters can't be zero */
	var->vsync_len = max_t(u32, var->vsync_len, 1);
	var->right_margin = max_t(u32, var->right_margin, 1);
	var->hsync_len = max_t(u32, var->hsync_len, 1);
	var->left_margin = max_t(u32, var->left_margin, 1);

	switch (var->bits_per_pixel) {
	case 1:
	case 2:
	case 4:
	case 8:
		var->red.offset = var->green.offset = var->blue.offset = 0;
		var->red.length = var->green.length = var->blue.length
			= var->bits_per_pixel;
		break;
	case 15:
	case 16:
		if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
			/* RGB:565 mode */
			var->red.offset = 11;
			var->blue.offset = 0;
			var->green.length = 6;
		} else if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB555) {
			var->red.offset = 10;
			var->blue.offset = 0;
			var->green.length = 5;
		} else {
			/* BGR:555 mode */
			var->red.offset = 0;
			var->blue.offset = 10;
			var->green.length = 5;
		}
		var->green.offset = 5;
		var->red.length = var->blue.length = 5;
		break;
	case 32:
		var->transp.offset = 24;
		var->transp.length = 8;
		/* fall through */
	case 24:
		if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
			/* RGB:888 mode */
			var->red.offset = 16;
			var->blue.offset = 0;
		} else {
			/* BGR:888 mode */
			var->red.offset = 0;
			var->blue.offset = 16;
		}
		var->green.offset = 8;
		var->red.length = var->green.length = var->blue.length = 8;
		break;
	default:
		dev_err(dev, "color depth %d not supported\n",
					var->bits_per_pixel);
		return -EINVAL;
	}

	return 0;
}

/*
 * LCD reset sequence
 */
static void atmel_lcdfb_reset(struct atmel_lcdfb_info *sinfo)
{
	might_sleep();

	atmel_lcdfb_stop(sinfo);
	atmel_lcdfb_start(sinfo);
}

/**
 *      atmel_lcdfb_set_par - Alters the hardware state.
 *      @info: frame buffer structure that represents a single frame buffer
 *
 *	Using the fb_var_screeninfo in fb_info we set the resolution
 *	of the this particular framebuffer. This function alters the
 *	par AND the fb_fix_screeninfo stored in fb_info. It doesn't
 *	not alter var in fb_info since we are using that data. This
 *	means we depend on the data in var inside fb_info to be
 *	supported by the hardware.  atmel_lcdfb_check_var is always called
 *	before atmel_lcdfb_set_par to ensure this.  Again if you can't
 *	change the resolution you don't need this function.
 *
 */
static int atmel_lcdfb_set_par(struct fb_info *info)
{
	struct atmel_lcdfb_info *sinfo = info->par;
	unsigned long hozval_linesz;
	unsigned long value;
	unsigned long clk_value_khz;
	unsigned long bits_per_line;
	unsigned long pix_factor = 2;

	might_sleep();

	dev_dbg(info->device, "%s:\n", __func__);
	dev_dbg(info->device, "  * resolution: %ux%u (%ux%u virtual)\n",
		 info->var.xres, info->var.yres,
		 info->var.xres_virtual, info->var.yres_virtual);

	atmel_lcdfb_stop_nowait(sinfo);

	if (info->var.bits_per_pixel == 1)
		info->fix.visual = FB_VISUAL_MONO01;
	else if (info->var.bits_per_pixel <= 8)
		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
	else
		info->fix.visual = FB_VISUAL_TRUECOLOR;

	bits_per_line = info->var.xres_virtual * info->var.bits_per_pixel;
	info->fix.line_length = DIV_ROUND_UP(bits_per_line, 8);

	/* Re-initialize the DMA engine... */
	dev_dbg(info->device, "  * update DMA engine\n");
	atmel_lcdfb_update_dma(info, &info->var);

	/* ...set frame size and burst length = 8 words (?) */
	value = (info->var.yres * info->var.xres * info->var.bits_per_pixel) / 32;
	value |= ((ATMEL_LCDC_DMA_BURST_LEN - 1) << ATMEL_LCDC_BLENGTH_OFFSET);
	lcdc_writel(sinfo, ATMEL_LCDC_DMAFRMCFG, value);

	/* Now, the LCDC core... */

	/* Set pixel clock */
	if (cpu_is_at91sam9g45() && !cpu_is_at91sam9g45es())
		pix_factor = 1;

	clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;

	value = DIV_ROUND_UP(clk_value_khz, PICOS2KHZ(info->var.pixclock));

	if (value < pix_factor) {
		dev_notice(info->device, "Bypassing pixel clock divider\n");
		lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);
	} else {
		value = (value / pix_factor) - 1;
		dev_dbg(info->device, "  * programming CLKVAL = 0x%08lx\n",
				value);
		lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1,
				value << ATMEL_LCDC_CLKVAL_OFFSET);
		info->var.pixclock =
			KHZ2PICOS(clk_value_khz / (pix_factor * (value + 1)));
		dev_dbg(info->device, "  updated pixclk:     %lu KHz\n",
					PICOS2KHZ(info->var.pixclock));
	}


	/* Initialize control register 2 */
	value = sinfo->default_lcdcon2;

	if (!(info->var.sync & FB_SYNC_HOR_HIGH_ACT))
		value |= ATMEL_LCDC_INVLINE_INVERTED;
	if (!(info->var.sync & FB_SYNC_VERT_HIGH_ACT))
		value |= ATMEL_LCDC_INVFRAME_INVERTED;

	switch (info->var.bits_per_pixel) {
		case 1:	value |= ATMEL_LCDC_PIXELSIZE_1; break;
		case 2: value |= ATMEL_LCDC_PIXELSIZE_2; break;
		case 4: value |= ATMEL_LCDC_PIXELSIZE_4; break;
		case 8: value |= ATMEL_LCDC_PIXELSIZE_8; break;
		case 15: /* fall through */
		case 16: value |= ATMEL_LCDC_PIXELSIZE_16; break;
		case 24: value |= ATMEL_LCDC_PIXELSIZE_24; break;
		case 32: value |= ATMEL_LCDC_PIXELSIZE_32; break;
		default: BUG(); break;
	}
	dev_dbg(info->device, "  * LCDCON2 = %08lx\n", value);
	lcdc_writel(sinfo, ATMEL_LCDC_LCDCON2, value);

	/* Vertical timing */
	value = (info->var.vsync_len - 1) << ATMEL_LCDC_VPW_OFFSET;
	value |= info->var.upper_margin << ATMEL_LCDC_VBP_OFFSET;
	value |= info->var.lower_margin;
	dev_dbg(info->device, "  * LCDTIM1 = %08lx\n", value);
	lcdc_writel(sinfo, ATMEL_LCDC_TIM1, value);

	/* Horizontal timing */
	value = (info->var.right_margin - 1) << ATMEL_LCDC_HFP_OFFSET;
	value |= (info->var.hsync_len - 1) << ATMEL_LCDC_HPW_OFFSET;
	value |= (info->var.left_margin - 1);
	dev_dbg(info->device, "  * LCDTIM2 = %08lx\n", value);
	lcdc_writel(sinfo, ATMEL_LCDC_TIM2, value);

	/* Horizontal value (aka line size) */
	hozval_linesz = compute_hozval(info->var.xres,
					lcdc_readl(sinfo, ATMEL_LCDC_LCDCON2));

	/* Display size */
	value = (hozval_linesz - 1) << ATMEL_LCDC_HOZVAL_OFFSET;
	value |= info->var.yres - 1;
	dev_dbg(info->device, "  * LCDFRMCFG = %08lx\n", value);
	lcdc_writel(sinfo, ATMEL_LCDC_LCDFRMCFG, value);

	/* FIFO Threshold: Use formula from data sheet */
	value = ATMEL_LCDC_FIFO_SIZE - (2 * ATMEL_LCDC_DMA_BURST_LEN + 3);
	lcdc_writel(sinfo, ATMEL_LCDC_FIFO, value);

	/* Toggle LCD_MODE every frame */
	lcdc_writel(sinfo, ATMEL_LCDC_MVAL, 0);

	/* Disable all interrupts */
	lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0UL);
	/* Enable FIFO & DMA errors */
	lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI | ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);

	/* ...wait for DMA engine to become idle... */
	while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
		msleep(10);

	atmel_lcdfb_start(sinfo);

	dev_dbg(info->device, "  * DONE\n");

	return 0;
}

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

/**
 *  	atmel_lcdfb_setcolreg - Optional function. Sets a color register.
 *      @regno: Which register in the CLUT we are programming
 *      @red: The red value which can be up to 16 bits wide
 *	@green: The green value which can be up to 16 bits wide
 *	@blue:  The blue value which can be up to 16 bits wide.
 *	@transp: If supported the alpha value which can be up to 16 bits wide.
 *      @info: frame buffer info structure
 *
 *  	Set a single color register. The values supplied have a 16 bit
 *  	magnitude which needs to be scaled in this function for the hardware.
 *	Things to take into consideration are how many color registers, if
 *	any, are supported with the current color visual. With truecolor mode
 *	no color palettes are supported. Here a pseudo palette is created
 *	which we store the value in pseudo_palette in struct fb_info. For
 *	pseudocolor mode we have a limited color palette. To deal with this
 *	we can program what color is displayed for a particular pixel value.
 *	DirectColor is similar in that we can program each color field. If
 *	we have a static colormap we don't need to implement this function.
 *
 *	Returns negative errno on error, or zero on success. In an
 *	ideal world, this would have been the case, but as it turns
 *	out, the other drivers return 1 on failure, so that's what
 *	we're going to do.
 */
static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red,
			     unsigned int green, unsigned int blue,
			     unsigned int transp, struct fb_info *info)
{
	struct atmel_lcdfb_info *sinfo = info->par;
	unsigned int val;
	u32 *pal;
	int ret = 1;

	if (info->var.grayscale)
		red = green = blue = (19595 * red + 38470 * green
				      + 7471 * blue) >> 16;

	switch (info->fix.visual) {
	case FB_VISUAL_TRUECOLOR:
		if (regno < 16) {
			pal = info->pseudo_palette;

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

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

	case FB_VISUAL_PSEUDOCOLOR:
		if (regno < 256) {
			val  = ((red   >> 11) & 0x001f);
			val |= ((green >>  6) & 0x03e0);
			val |= ((blue  >>  1) & 0x7c00);

			/*
			 * TODO: intensity bit. Maybe something like
			 *   ~(red[10] ^ green[10] ^ blue[10]) & 1
			 */

			lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
			ret = 0;
		}
		break;

	case FB_VISUAL_MONO01:
		if (regno < 2) {
			val = (regno == 0) ? 0x00 : 0x1F;
			lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);
			ret = 0;
		}
		break;

	}

	return ret;
}

static int atmel_lcdfb_pan_display(struct fb_var_screeninfo *var,
			       struct fb_info *info)
{
	dev_dbg(info->device, "%s\n", __func__);

	atmel_lcdfb_update_dma(info, var);

	return 0;
}

static int atmel_lcdfb_blank(int blank_mode, struct fb_info *info)
{
	struct atmel_lcdfb_info *sinfo = info->par;

	switch (blank_mode) {
	case FB_BLANK_UNBLANK:
	case FB_BLANK_NORMAL:
		atmel_lcdfb_start(sinfo);
		break;
	case FB_BLANK_VSYNC_SUSPEND:
	case FB_BLANK_HSYNC_SUSPEND:
		break;
	case FB_BLANK_POWERDOWN:
		atmel_lcdfb_stop(sinfo);
		break;
	default:
		return -EINVAL;
	}

	/* let fbcon do a soft blank for us */
	return ((blank_mode == FB_BLANK_NORMAL) ? 1 : 0);
}

static struct fb_ops atmel_lcdfb_ops = {
	.owner		= THIS_MODULE,
	.fb_check_var	= atmel_lcdfb_check_var,
	.fb_set_par	= atmel_lcdfb_set_par,
	.fb_setcolreg	= atmel_lcdfb_setcolreg,
	.fb_blank	= atmel_lcdfb_blank,
	.fb_pan_display	= atmel_lcdfb_pan_display,
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
};

static irqreturn_t atmel_lcdfb_interrupt(int irq, void *dev_id)
{
	struct fb_info *info = dev_id;
	struct atmel_lcdfb_info *sinfo = info->par;
	u32 status;

	status = lcdc_readl(sinfo, ATMEL_LCDC_ISR);
	if (status & ATMEL_LCDC_UFLWI) {
		dev_warn(info->device, "FIFO underflow %#x\n", status);
		/* reset DMA and FIFO to avoid screen shifting */
		schedule_work(&sinfo->task);
	}
	lcdc_writel(sinfo, ATMEL_LCDC_ICR, status);
	return IRQ_HANDLED;
}

/*
 * LCD controller task (to reset the LCD)
 */
static void atmel_lcdfb_task(struct work_struct *work)
{
	struct atmel_lcdfb_info *sinfo =
		container_of(work, struct atmel_lcdfb_info, task);

	atmel_lcdfb_reset(sinfo);
}

static int __init atmel_lcdfb_init_fbinfo(struct atmel_lcdfb_info *sinfo)
{
	struct fb_info *info = sinfo->info;
	int ret = 0;

	info->var.activate |= FB_ACTIVATE_FORCE | FB_ACTIVATE_NOW;

	dev_info(info->device,
	       "%luKiB frame buffer at %08lx (mapped at %p)\n",
	       (unsigned long)info->fix.smem_len / 1024,
	       (unsigned long)info->fix.smem_start,
	       info->screen_base);

	/* Allocate colormap */
	ret = fb_alloc_cmap(&info->cmap, 256, 0);
	if (ret < 0)
		dev_err(info->device, "Alloc color map failed\n");

	return ret;
}

static void atmel_lcdfb_start_clock(struct atmel_lcdfb_info *sinfo)
{
	if (sinfo->bus_clk)
		clk_enable(sinfo->bus_clk);
	clk_enable(sinfo->lcdc_clk);
}

static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
{
	if (sinfo->bus_clk)
		clk_disable(sinfo->bus_clk);
	clk_disable(sinfo->lcdc_clk);
}


static int __init atmel_lcdfb_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct fb_info *info;
	struct atmel_lcdfb_info *sinfo;
	struct atmel_lcdfb_info *pdata_sinfo;
	struct fb_videomode fbmode;
	struct resource *regs = NULL;
	struct resource *map = NULL;
	int ret;

	dev_dbg(dev, "%s BEGIN\n", __func__);

	ret = -ENOMEM;
	info = framebuffer_alloc(sizeof(struct atmel_lcdfb_info), dev);
	if (!info) {
		dev_err(dev, "cannot allocate memory\n");
		goto out;
	}

	sinfo = info->par;

	if (dev->platform_data) {
		pdata_sinfo = (struct atmel_lcdfb_info *)dev->platform_data;
		sinfo->default_bpp = pdata_sinfo->default_bpp;
		sinfo->default_dmacon = pdata_sinfo->default_dmacon;
		sinfo->default_lcdcon2 = pdata_sinfo->default_lcdcon2;
		sinfo->default_monspecs = pdata_sinfo->default_monspecs;
		sinfo->atmel_lcdfb_power_control = pdata_sinfo->atmel_lcdfb_power_control;
		sinfo->guard_time = pdata_sinfo->guard_time;
		sinfo->smem_len = pdata_sinfo->smem_len;
		sinfo->lcdcon_is_backlight = pdata_sinfo->lcdcon_is_backlight;
		sinfo->lcdcon_pol_negative = pdata_sinfo->lcdcon_pol_negative;
		sinfo->lcd_wiring_mode = pdata_sinfo->lcd_wiring_mode;
	} else {
		dev_err(dev, "cannot get default configuration\n");
		goto free_info;
	}
	sinfo->info = info;
	sinfo->pdev = pdev;

	strcpy(info->fix.id, sinfo->pdev->name);
	info->flags = ATMEL_LCDFB_FBINFO_DEFAULT;
	info->pseudo_palette = sinfo->pseudo_palette;
	info->fbops = &atmel_lcdfb_ops;

	memcpy(&info->monspecs, sinfo->default_monspecs, sizeof(info->monspecs));
	info->fix = atmel_lcdfb_fix;

	/* Enable LCDC Clocks */
	if (cpu_is_at91sam9261() || cpu_is_at91sam9g10()
	 || cpu_is_at32ap7000()) {
		sinfo->bus_clk = clk_get(dev, "hck1");
		if (IS_ERR(sinfo->bus_clk)) {
			ret = PTR_ERR(sinfo->bus_clk);
			goto free_info;
		}
	}
	sinfo->lcdc_clk = clk_get(dev, "lcdc_clk");
	if (IS_ERR(sinfo->lcdc_clk)) {
		ret = PTR_ERR(sinfo->lcdc_clk);
		goto put_bus_clk;
	}
	atmel_lcdfb_start_clock(sinfo);

	ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
			info->monspecs.modedb_len, info->monspecs.modedb,
			sinfo->default_bpp);
	if (!ret) {
		dev_err(dev, "no suitable video mode found\n");
		goto stop_clk;
	}


	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!regs) {
		dev_err(dev, "resources unusable\n");
		ret = -ENXIO;
		goto stop_clk;
	}

	sinfo->irq_base = platform_get_irq(pdev, 0);
	if (sinfo->irq_base < 0) {
		dev_err(dev, "unable to get irq\n");
		ret = sinfo->irq_base;
		goto stop_clk;
	}

	/* Initialize video memory */
	map = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	if (map) {
		/* use a pre-allocated memory buffer */
		info->fix.smem_start = map->start;
		info->fix.smem_len = resource_size(map);
		if (!request_mem_region(info->fix.smem_start,
					info->fix.smem_len, pdev->name)) {
			ret = -EBUSY;
			goto stop_clk;
		}

		info->screen_base = ioremap(info->fix.smem_start, info->fix.smem_len);
		if (!info->screen_base)
			goto release_intmem;

		/*
		 * Don't clear the framebuffer -- someone may have set
		 * up a splash image.
		 */
	} else {
		/* alocate memory buffer */
		ret = atmel_lcdfb_alloc_video_memory(sinfo);
		if (ret < 0) {
			dev_err(dev, "cannot allocate framebuffer: %d\n", ret);
			goto stop_clk;
		}
	}

	/* LCDC registers */
	info->fix.mmio_start = regs->start;
	info->fix.mmio_len = resource_size(regs);

	if (!request_mem_region(info->fix.mmio_start,
				info->fix.mmio_len, pdev->name)) {
		ret = -EBUSY;
		goto free_fb;
	}

	sinfo->mmio = ioremap(info->fix.mmio_start, info->fix.mmio_len);
	if (!sinfo->mmio) {
		dev_err(dev, "cannot map LCDC registers\n");
		goto release_mem;
	}

	/* Initialize PWM for contrast or backlight ("off") */
	init_contrast(sinfo);

	/* interrupt */
	ret = request_irq(sinfo->irq_base, atmel_lcdfb_interrupt, 0, pdev->name, info);
	if (ret) {
		dev_err(dev, "request_irq failed: %d\n", ret);
		goto unmap_mmio;
	}

	/* Some operations on the LCDC might sleep and
	 * require a preemptible task context */
	INIT_WORK(&sinfo->task, atmel_lcdfb_task);

	ret = atmel_lcdfb_init_fbinfo(sinfo);
	if (ret < 0) {
		dev_err(dev, "init fbinfo failed: %d\n", ret);
		goto unregister_irqs;
	}

	/*
	 * This makes sure that our colour bitfield
	 * descriptors are correctly initialised.
	 */
	atmel_lcdfb_check_var(&info->var, info);

	ret = fb_set_var(info, &info->var);
	if (ret) {
		dev_warn(dev, "unable to set display parameters\n");
		goto free_cmap;
	}

	dev_set_drvdata(dev, info);

	/*
	 * Tell the world that we're ready to go
	 */
	ret = register_framebuffer(info);
	if (ret < 0) {
		dev_err(dev, "failed to register framebuffer device: %d\n", ret);
		goto reset_drvdata;
	}

	/* add selected videomode to modelist */
	fb_var_to_videomode(&fbmode, &info->var);
	fb_add_videomode(&fbmode, &info->modelist);

	/* Power up the LCDC screen */
	if (sinfo->atmel_lcdfb_power_control)
		sinfo->atmel_lcdfb_power_control(1);

	dev_info(dev, "fb%d: Atmel LCDC at 0x%08lx (mapped at %p), irq %d\n",
		       info->node, info->fix.mmio_start, sinfo->mmio, sinfo->irq_base);

	return 0;

reset_drvdata:
	dev_set_drvdata(dev, NULL);
free_cmap:
	fb_dealloc_cmap(&info->cmap);
unregister_irqs:
	cancel_work_sync(&sinfo->task);
	free_irq(sinfo->irq_base, info);
unmap_mmio:
	exit_backlight(sinfo);
	iounmap(sinfo->mmio);
release_mem:
 	release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
free_fb:
	if (map)
		iounmap(info->screen_base);
	else
		atmel_lcdfb_free_video_memory(sinfo);

release_intmem:
	if (map)
		release_mem_region(info->fix.smem_start, info->fix.smem_len);
stop_clk:
	atmel_lcdfb_stop_clock(sinfo);
	clk_put(sinfo->lcdc_clk);
put_bus_clk:
	if (sinfo->bus_clk)
		clk_put(sinfo->bus_clk);
free_info:
	framebuffer_release(info);
out:
	dev_dbg(dev, "%s FAILED\n", __func__);
	return ret;
}

static int __exit atmel_lcdfb_remove(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct fb_info *info = dev_get_drvdata(dev);
	struct atmel_lcdfb_info *sinfo;

	if (!info || !info->par)
		return 0;
	sinfo = info->par;

	cancel_work_sync(&sinfo->task);
	exit_backlight(sinfo);
	if (sinfo->atmel_lcdfb_power_control)
		sinfo->atmel_lcdfb_power_control(0);
	unregister_framebuffer(info);
	atmel_lcdfb_stop_clock(sinfo);
	clk_put(sinfo->lcdc_clk);
	if (sinfo->bus_clk)
		clk_put(sinfo->bus_clk);
	fb_dealloc_cmap(&info->cmap);
	free_irq(sinfo->irq_base, info);
	iounmap(sinfo->mmio);
 	release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
	if (platform_get_resource(pdev, IORESOURCE_MEM, 1)) {
		iounmap(info->screen_base);
		release_mem_region(info->fix.smem_start, info->fix.smem_len);
	} else {
		atmel_lcdfb_free_video_memory(sinfo);
	}

	dev_set_drvdata(dev, NULL);
	framebuffer_release(info);

	return 0;
}

#ifdef CONFIG_PM

static int atmel_lcdfb_suspend(struct platform_device *pdev, pm_message_t mesg)
{
	struct fb_info *info = platform_get_drvdata(pdev);
	struct atmel_lcdfb_info *sinfo = info->par;

	/*
	 * We don't want to handle interrupts while the clock is
	 * stopped. It may take forever.
	 */
	lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0UL);

	sinfo->saved_lcdcon = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, 0);
	if (sinfo->atmel_lcdfb_power_control)
		sinfo->atmel_lcdfb_power_control(0);

	atmel_lcdfb_stop(sinfo);
	atmel_lcdfb_stop_clock(sinfo);

	return 0;
}

static int atmel_lcdfb_resume(struct platform_device *pdev)
{
	struct fb_info *info = platform_get_drvdata(pdev);
	struct atmel_lcdfb_info *sinfo = info->par;

	atmel_lcdfb_start_clock(sinfo);
	atmel_lcdfb_start(sinfo);
	if (sinfo->atmel_lcdfb_power_control)
		sinfo->atmel_lcdfb_power_control(1);
	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, sinfo->saved_lcdcon);

	/* Enable FIFO & DMA errors */
	lcdc_writel(sinfo, ATMEL_LCDC_IER, ATMEL_LCDC_UFLWI
			| ATMEL_LCDC_OWRI | ATMEL_LCDC_MERI);

	return 0;
}

#else
#define atmel_lcdfb_suspend	NULL
#define atmel_lcdfb_resume	NULL
#endif

static struct platform_driver atmel_lcdfb_driver = {
	.remove		= __exit_p(atmel_lcdfb_remove),
	.suspend	= atmel_lcdfb_suspend,
	.resume		= atmel_lcdfb_resume,

	.driver		= {
		.name	= "atmel_lcdfb",
		.owner	= THIS_MODULE,
	},
};

static int __init atmel_lcdfb_init(void)
{
	return platform_driver_probe(&atmel_lcdfb_driver, atmel_lcdfb_probe);
}

static void __exit atmel_lcdfb_exit(void)
{
	platform_driver_unregister(&atmel_lcdfb_driver);
}

module_init(atmel_lcdfb_init);
module_exit(atmel_lcdfb_exit);

MODULE_DESCRIPTION("AT91/AT32 LCD Controller framebuffer driver");
MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>");
MODULE_LICENSE("GPL");

Privacy Policy