aboutsummaryrefslogtreecommitdiff
path: root/drivers/video/nuc900fb.c
blob: d4cde79ea15e61362a34736179520053d68383bc (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
/*
 *
 * Copyright (c) 2009 Nuvoton technology corporation
 * 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.
 *
 *  Description:
 *    Nuvoton LCD Controller Driver
 *  Author:
 *    Wang Qiang (rurality.linux@gmail.com) 2009/12/11
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/wait.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/io.h>
#include <linux/pm.h>
#include <linux/device.h>

#include <mach/map.h>
#include <mach/regs-clock.h>
#include <mach/regs-ldm.h>
#include <mach/fb.h>
#include <mach/clkdev.h>

#include "nuc900fb.h"


/*
 *  Initialize the nuc900 video (dual) buffer address
 */
static void nuc900fb_set_lcdaddr(struct fb_info *info)
{
	struct nuc900fb_info *fbi = info->par;
	void __iomem *regs = fbi->io;
	unsigned long vbaddr1, vbaddr2;

	vbaddr1  = info->fix.smem_start;
	vbaddr2  = info->fix.smem_start;
	vbaddr2 += info->fix.line_length * info->var.yres;

	/* set frambuffer start phy addr*/
	writel(vbaddr1, regs + REG_LCM_VA_BADDR0);
	writel(vbaddr2, regs + REG_LCM_VA_BADDR1);

	writel(fbi->regs.lcd_va_fbctrl, regs + REG_LCM_VA_FBCTRL);
	writel(fbi->regs.lcd_va_scale, regs + REG_LCM_VA_SCALE);
}

/*
 *	calculate divider for lcd div
 */
static unsigned int nuc900fb_calc_pixclk(struct nuc900fb_info *fbi,
					 unsigned long pixclk)
{
	unsigned long clk = fbi->clk_rate;
	unsigned long long div;

	/* pixclk is in picseconds. our clock is in Hz*/
	/* div = (clk * pixclk)/10^12 */
	div = (unsigned long long)clk * pixclk;
	div >>= 12;
	do_div(div, 625 * 625UL * 625);

	dev_dbg(fbi->dev, "pixclk %ld, divisor is %lld\n", pixclk, div);

	return div;
}

/*
 *	Check the video params of 'var'.
 */
static int nuc900fb_check_var(struct fb_var_screeninfo *var,
			       struct fb_info *info)
{
	struct nuc900fb_info *fbi = info->par;
	struct nuc900fb_mach_info *mach_info = fbi->dev->platform_data;
	struct nuc900fb_display *display = NULL;
	struct nuc900fb_display *default_display = mach_info->displays +
						   mach_info->default_display;
	int i;

	dev_dbg(fbi->dev, "check_var(var=%p, info=%p)\n", var, info);

	/* validate x/y resolution */
	/* choose default mode if possible */
	if (var->xres == default_display->xres &&
	    var->yres == default_display->yres &&
	    var->bits_per_pixel == default_display->bpp)
		display = default_display;
	else
		for (i = 0; i < mach_info->num_displays; i++)
			if (var->xres == mach_info->displays[i].xres &&
			    var->yres == mach_info->displays[i].yres &&
			    var->bits_per_pixel == mach_info->displays[i].bpp) {
				display = mach_info->displays + i;
				break;
			}

	if (display == NULL) {
		printk(KERN_ERR "wrong resolution or depth %dx%d at %d bit per pixel\n",
			var->xres, var->yres, var->bits_per_pixel);
		return -EINVAL;
	}

	/* it should be the same size as the display */
	var->xres_virtual	= display->xres;
	var->yres_virtual	= display->yres;
	var->height		= display->height;
	var->width		= display->width;

	/* copy lcd settings */
	var->pixclock		= display->pixclock;
	var->left_margin	= display->left_margin;
	var->right_margin	= display->right_margin;
	var->upper_margin	= display->upper_margin;
	var->lower_margin	= display->lower_margin;
	var->vsync_len		= display->vsync_len;
	var->hsync_len		= display->hsync_len;

	var->transp.offset	= 0;
	var->transp.length	= 0;

	fbi->regs.lcd_dccs = display->dccs;
	fbi->regs.lcd_device_ctrl = display->devctl;
	fbi->regs.lcd_va_fbctrl = display->fbctrl;
	fbi->regs.lcd_va_scale = display->scale;

	/* set R/G/B possions */
	switch (var->bits_per_pixel) {
	case 1:
	case 2:
	case 4:
	case 8:
	default:
		var->red.offset 	= 0;
		var->red.length 	= var->bits_per_pixel;
		var->green 		= var->red;
		var->blue		= var->red;
		break;
	case 12:
		var->red.length		= 4;
		var->green.length	= 4;
		var->blue.length	= 4;
		var->red.offset		= 8;
		var->green.offset	= 4;
		var->blue.offset	= 0;
		break;
	case 16:
		var->red.length		= 5;
		var->green.length	= 6;
		var->blue.length	= 5;
		var->red.offset		= 11;
		var->green.offset	= 5;
		var->blue.offset	= 0;
		break;
	case 18:
		var->red.length		= 6;
		var->green.length	= 6;
		var->blue.length	= 6;
		var->red.offset		= 12;
		var->green.offset	= 6;
		var->blue.offset	= 0;
		break;
	case 32:
		var->red.length		= 8;
		var->green.length	= 8;
		var->blue.length	= 8;
		var->red.offset		= 16;
		var->green.offset	= 8;
		var->blue.offset	= 0;
		break;
	}

	return 0;
}

/*
 *	Calculate lcd register values from var setting & save into hw
 */
static void nuc900fb_calculate_lcd_regs(const struct fb_info *info,
					struct nuc900fb_hw *regs)
{
	const struct fb_var_screeninfo *var = &info->var;
	int vtt = var->height + var->upper_margin + var->lower_margin;
	int htt = var->width + var->left_margin + var->right_margin;
	int hsync = var->width + var->right_margin;
	int vsync = var->height + var->lower_margin;

	regs->lcd_crtc_size = LCM_CRTC_SIZE_VTTVAL(vtt) |
			      LCM_CRTC_SIZE_HTTVAL(htt);
	regs->lcd_crtc_dend = LCM_CRTC_DEND_VDENDVAL(var->height) |
			      LCM_CRTC_DEND_HDENDVAL(var->width);
	regs->lcd_crtc_hr = LCM_CRTC_HR_EVAL(var->width + 5) |
			    LCM_CRTC_HR_SVAL(var->width + 1);
	regs->lcd_crtc_hsync = LCM_CRTC_HSYNC_EVAL(hsync + var->hsync_len) |
			       LCM_CRTC_HSYNC_SVAL(hsync);
	regs->lcd_crtc_vr = LCM_CRTC_VR_EVAL(vsync + var->vsync_len) |
			    LCM_CRTC_VR_SVAL(vsync);

}

/*
 *	Activate (set) the controller from the given framebuffer
 *	information
 */
static void nuc900fb_activate_var(struct fb_info *info)
{
	struct nuc900fb_info *fbi = info->par;
	void __iomem *regs = fbi->io;
	struct fb_var_screeninfo *var = &info->var;
	int clkdiv;

	clkdiv = nuc900fb_calc_pixclk(fbi, var->pixclock) - 1;
	if (clkdiv < 0)
		clkdiv = 0;

	nuc900fb_calculate_lcd_regs(info, &fbi->regs);

	/* set the new lcd registers*/

	dev_dbg(fbi->dev, "new lcd register set:\n");
	dev_dbg(fbi->dev, "dccs       = 0x%08x\n", fbi->regs.lcd_dccs);
	dev_dbg(fbi->dev, "dev_ctl    = 0x%08x\n", fbi->regs.lcd_device_ctrl);
	dev_dbg(fbi->dev, "crtc_size  = 0x%08x\n", fbi->regs.lcd_crtc_size);
	dev_dbg(fbi->dev, "crtc_dend  = 0x%08x\n", fbi->regs.lcd_crtc_dend);
	dev_dbg(fbi->dev, "crtc_hr    = 0x%08x\n", fbi->regs.lcd_crtc_hr);
	dev_dbg(fbi->dev, "crtc_hsync = 0x%08x\n", fbi->regs.lcd_crtc_hsync);
	dev_dbg(fbi->dev, "crtc_vr    = 0x%08x\n", fbi->regs.lcd_crtc_vr);

	writel(fbi->regs.lcd_device_ctrl, regs + REG_LCM_DEV_CTRL);
	writel(fbi->regs.lcd_crtc_size, regs + REG_LCM_CRTC_SIZE);
	writel(fbi->regs.lcd_crtc_dend, regs + REG_LCM_CRTC_DEND);
	writel(fbi->regs.lcd_crtc_hr, regs + REG_LCM_CRTC_HR);
	writel(fbi->regs.lcd_crtc_hsync, regs + REG_LCM_CRTC_HSYNC);
	writel(fbi->regs.lcd_crtc_vr, regs + REG_LCM_CRTC_VR);

	/* set lcd address pointers */
	nuc900fb_set_lcdaddr(info);

	writel(fbi->regs.lcd_dccs, regs + REG_LCM_DCCS);
}

/*
 *      Alters the hardware state.
 *
 */
static int nuc900fb_set_par(struct fb_info *info)
{
	struct fb_var_screeninfo *var = &info->var;

	switch (var->bits_per_pixel) {
	case 32:
	case 24:
	case 18:
	case 16:
	case 12:
		info->fix.visual = FB_VISUAL_TRUECOLOR;
		break;
	case 1:
		info->fix.visual = FB_VISUAL_MONO01;
		break;
	default:
		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
		break;
	}

	info->fix.line_length = (var->xres_virtual * var->bits_per_pixel) / 8;

	/* activate this new configuration */
	nuc900fb_activate_var(info);
	return 0;
}

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

static int nuc900fb_setcolreg(unsigned regno,
			       unsigned red, unsigned green, unsigned blue,
			       unsigned transp, struct fb_info *info)
{
	unsigned int val;

	switch (info->fix.visual) {
	case FB_VISUAL_TRUECOLOR:
		/* true-colour, use pseuo-palette */
		if (regno < 16) {
			u32 *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;
		}
		break;

	default:
		return 1;   /* unknown type */
	}
	return 0;
}

/**
 *      nuc900fb_blank
 *
 */
static int nuc900fb_blank(int blank_mode, struct fb_info *info)
{

	return 0;
}

static struct fb_ops nuc900fb_ops = {
	.owner			= THIS_MODULE,
	.fb_check_var		= nuc900fb_check_var,
	.fb_set_par		= nuc900fb_set_par,
	.fb_blank		= nuc900fb_blank,
	.fb_setcolreg		= nuc900fb_setcolreg,
	.fb_fillrect		= cfb_fillrect,
	.fb_copyarea		= cfb_copyarea,
	.fb_imageblit		= cfb_imageblit,
};


static inline void modify_gpio(void __iomem *reg,
			       unsigned long set, unsigned long mask)
{
	unsigned long tmp;
	tmp = readl(reg) & ~mask;
	writel(tmp | set, reg);
}

/*
 * Initialise LCD-related registers
 */
static int nuc900fb_init_registers(struct fb_info *info)
{
	struct nuc900fb_info *fbi = info->par;
	struct nuc900fb_mach_info *mach_info = fbi->dev->platform_data;
	void __iomem *regs = fbi->io;

	/*reset the display engine*/
	writel(0, regs + REG_LCM_DCCS);
	writel(readl(regs + REG_LCM_DCCS) | LCM_DCCS_ENG_RST,
	       regs + REG_LCM_DCCS);
	ndelay(100);
	writel(readl(regs + REG_LCM_DCCS) & (~LCM_DCCS_ENG_RST),
	       regs + REG_LCM_DCCS);
	ndelay(100);

	writel(0, regs + REG_LCM_DEV_CTRL);

	/* config gpio output */
	modify_gpio(W90X900_VA_GPIO + 0x54, mach_info->gpio_dir,
		    mach_info->gpio_dir_mask);
	modify_gpio(W90X900_VA_GPIO + 0x58, mach_info->gpio_data,
		    mach_info->gpio_data_mask);

	return 0;
}


/*
 *    Alloc the SDRAM region of NUC900 for the frame buffer.
 *    The buffer should be a non-cached, non-buffered, memory region
 *    to allow palette and pixel writes without flushing the cache.
 */
static int __init nuc900fb_map_video_memory(struct fb_info *info)
{
	struct nuc900fb_info *fbi = info->par;
	dma_addr_t map_dma;
	unsigned long map_size = PAGE_ALIGN(info->fix.smem_len);

	dev_dbg(fbi->dev, "nuc900fb_map_video_memory(fbi=%p) map_size %lu\n",
		fbi, map_size);

	info->screen_base = dma_alloc_writecombine(fbi->dev, map_size,
							&map_dma, GFP_KERNEL);

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

	memset(info->screen_base, 0x00, map_size);
	info->fix.smem_start = map_dma;

	return 0;
}

static inline void nuc900fb_unmap_video_memory(struct fb_info *info)
{
	struct nuc900fb_info *fbi = info->par;
	dma_free_writecombine(fbi->dev, PAGE_ALIGN(info->fix.smem_len),
			      info->screen_base, info->fix.smem_start);
}

static irqreturn_t nuc900fb_irqhandler(int irq, void *dev_id)
{
	struct nuc900fb_info *fbi = dev_id;
	void __iomem *regs = fbi->io;
	void __iomem *irq_base = fbi->irq_base;
	unsigned long lcdirq = readl(regs + REG_LCM_INT_CS);

	if (lcdirq & LCM_INT_CS_DISP_F_STATUS) {
		writel(readl(irq_base) | 1<<30, irq_base);

		/* wait VA_EN low */
		if ((readl(regs + REG_LCM_DCCS) &
		    LCM_DCCS_SINGLE) == LCM_DCCS_SINGLE)
			while ((readl(regs + REG_LCM_DCCS) &
			       LCM_DCCS_VA_EN) == LCM_DCCS_VA_EN)
				;
		/* display_out-enable */
		writel(readl(regs + REG_LCM_DCCS) | LCM_DCCS_DISP_OUT_EN,
			regs + REG_LCM_DCCS);
		/* va-enable*/
		writel(readl(regs + REG_LCM_DCCS) | LCM_DCCS_VA_EN,
			regs + REG_LCM_DCCS);
	} else if (lcdirq & LCM_INT_CS_UNDERRUN_INT) {
		writel(readl(irq_base) | LCM_INT_CS_UNDERRUN_INT, irq_base);
	} else if (lcdirq & LCM_INT_CS_BUS_ERROR_INT) {
		writel(readl(irq_base) | LCM_INT_CS_BUS_ERROR_INT, irq_base);
	}

	return IRQ_HANDLED;
}

#ifdef CONFIG_CPU_FREQ

static int nuc900fb_cpufreq_transition(struct notifier_block *nb,
				       unsigned long val, void *data)
{
	struct nuc900fb_info *info;
	struct fb_info *fbinfo;
	long delta_f;
	info = container_of(nb, struct nuc900fb_info, freq_transition);
	fbinfo = platform_get_drvdata(to_platform_device(info->dev));

	delta_f = info->clk_rate - clk_get_rate(info->clk);

	if ((val == CPUFREQ_POSTCHANGE && delta_f > 0) ||
	   (val == CPUFREQ_PRECHANGE && delta_f < 0)) {
		info->clk_rate = clk_get_rate(info->clk);
		nuc900fb_activate_var(fbinfo);
	}

	return 0;
}

static inline int nuc900fb_cpufreq_register(struct nuc900fb_info *fbi)
{
	fbi->freq_transition.notifier_call = nuc900fb_cpufreq_transition;
	return cpufreq_register_notifier(&fbi->freq_transition,
				  CPUFREQ_TRANSITION_NOTIFIER);
}

static inline void nuc900fb_cpufreq_deregister(struct nuc900fb_info *fbi)
{
	cpufreq_unregister_notifier(&fbi->freq_transition,
				    CPUFREQ_TRANSITION_NOTIFIER);
}
#else
static inline int nuc900fb_cpufreq_transition(struct notifier_block *nb,
				       unsigned long val, void *data)
{
	return 0;
}

static inline int nuc900fb_cpufreq_register(struct nuc900fb_info *fbi)
{
	return 0;
}

static inline void nuc900fb_cpufreq_deregister(struct nuc900fb_info *info)
{
}
#endif

static char driver_name[] = "nuc900fb";

static int __devinit nuc900fb_probe(struct platform_device *pdev)
{
	struct nuc900fb_info *fbi;
	struct nuc900fb_display *display;
	struct fb_info	   *fbinfo;
	struct nuc900fb_mach_info *mach_info;
	struct resource *res;
	int ret;
	int irq;
	int i;
	int size;

	dev_dbg(&pdev->dev, "devinit\n");
	mach_info = pdev->dev.platform_data;
	if (mach_info == NULL) {
		dev_err(&pdev->dev,
			"no platform data for lcd, cannot attach\n");
		return -EINVAL;
	}

	if (mach_info->default_display > mach_info->num_displays) {
		dev_err(&pdev->dev,
			"default display No. is %d but only %d displays \n",
			mach_info->default_display, mach_info->num_displays);
		return -EINVAL;
	}


	display = mach_info->displays + mach_info->default_display;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_err(&pdev->dev, "no irq for device\n");
		return -ENOENT;
	}

	fbinfo = framebuffer_alloc(sizeof(struct nuc900fb_info), &pdev->dev);
	if (!fbinfo)
		return -ENOMEM;

	platform_set_drvdata(pdev, fbinfo);

	fbi = fbinfo->par;
	fbi->dev = &pdev->dev;

#ifdef CONFIG_CPU_NUC950
	fbi->drv_type = LCDDRV_NUC950;
#endif

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	size = (res->end - res->start) + 1;
	fbi->mem = request_mem_region(res->start, size, pdev->name);
	if (fbi->mem == NULL) {
		dev_err(&pdev->dev, "failed to alloc memory region\n");
		ret = -ENOENT;
		goto free_fb;
	}

	fbi->io = ioremap(res->start, size);
	if (fbi->io == NULL) {
		dev_err(&pdev->dev, "ioremap() of lcd registers failed\n");
		ret = -ENXIO;
		goto release_mem_region;
	}

	fbi->irq_base = fbi->io + REG_LCM_INT_CS;


	/* Stop the LCD */
	writel(0, fbi->io + REG_LCM_DCCS);

	/* fill the fbinfo*/
	strcpy(fbinfo->fix.id, driver_name);
	fbinfo->fix.type		= FB_TYPE_PACKED_PIXELS;
	fbinfo->fix.type_aux		= 0;
	fbinfo->fix.xpanstep		= 0;
	fbinfo->fix.ypanstep		= 0;
	fbinfo->fix.ywrapstep		= 0;
	fbinfo->fix.accel		= FB_ACCEL_NONE;
	fbinfo->var.nonstd		= 0;
	fbinfo->var.activate		= FB_ACTIVATE_NOW;
	fbinfo->var.accel_flags		= 0;
	fbinfo->var.vmode		= FB_VMODE_NONINTERLACED;
	fbinfo->fbops			= &nuc900fb_ops;
	fbinfo->flags			= FBINFO_FLAG_DEFAULT;
	fbinfo->pseudo_palette		= &fbi->pseudo_pal;

	ret = request_irq(irq, nuc900fb_irqhandler, IRQF_DISABLED,
			  pdev->name, fbinfo);
	if (ret) {
		dev_err(&pdev->dev, "cannot register irq handler %d -err %d\n",
			irq, ret);
		ret = -EBUSY;
		goto release_regs;
	}

	nuc900_driver_clksrc_div(&pdev->dev, "ext", 0x2);

	fbi->clk = clk_get(&pdev->dev, NULL);
	if (!fbi->clk || IS_ERR(fbi->clk)) {
		printk(KERN_ERR "nuc900-lcd:failed to get lcd clock source\n");
		ret = -ENOENT;
		goto release_irq;
	}

	clk_enable(fbi->clk);
	dev_dbg(&pdev->dev, "got and enabled clock\n");

	fbi->clk_rate = clk_get_rate(fbi->clk);

	/* calutate the video buffer size */
	for (i = 0; i < mach_info->num_displays; i++) {
		unsigned long smem_len = mach_info->displays[i].xres;
		smem_len *= mach_info->displays[i].yres;
		smem_len *= mach_info->displays[i].bpp;
		smem_len >>= 3;
		if (fbinfo->fix.smem_len < smem_len)
			fbinfo->fix.smem_len = smem_len;
	}

	/* Initialize Video Memory */
	ret = nuc900fb_map_video_memory(fbinfo);
	if (ret) {
		printk(KERN_ERR "Failed to allocate video RAM: %x\n", ret);
		goto release_clock;
	}

	dev_dbg(&pdev->dev, "got video memory\n");

	fbinfo->var.xres = display->xres;
	fbinfo->var.yres = display->yres;
	fbinfo->var.bits_per_pixel = display->bpp;

	nuc900fb_init_registers(fbinfo);

	nuc900fb_check_var(&fbinfo->var, fbinfo);

	ret = nuc900fb_cpufreq_register(fbi);
	if (ret < 0) {
		dev_err(&pdev->dev, "Failed to register cpufreq\n");
		goto free_video_memory;
	}

	ret = register_framebuffer(fbinfo);
	if (ret) {
		printk(KERN_ERR "failed to register framebuffer device: %d\n",
			ret);
		goto free_cpufreq;
	}

	printk(KERN_INFO "fb%d: %s frame buffer device\n",
		fbinfo->node, fbinfo->fix.id);

	return 0;

free_cpufreq:
	nuc900fb_cpufreq_deregister(fbi);
free_video_memory:
	nuc900fb_unmap_video_memory(fbinfo);
release_clock:
	clk_disable(fbi->clk);
	clk_put(fbi->clk);
release_irq:
	free_irq(irq, fbi);
release_regs:
	iounmap(fbi->io);
release_mem_region:
	release_mem_region(res->start, size);
free_fb:
	framebuffer_release(fbinfo);
	return ret;
}

/*
 * shutdown the lcd controller
 */
static void nuc900fb_stop_lcd(struct fb_info *info)
{
	struct nuc900fb_info *fbi = info->par;
	void __iomem *regs = fbi->io;

	writel((~LCM_DCCS_DISP_INT_EN) | (~LCM_DCCS_VA_EN) | (~LCM_DCCS_OSD_EN),
		regs + REG_LCM_DCCS);
}

/*
 *  Cleanup
 */
static int nuc900fb_remove(struct platform_device *pdev)
{
	struct fb_info *fbinfo = platform_get_drvdata(pdev);
	struct nuc900fb_info *fbi = fbinfo->par;
	int irq;

	nuc900fb_stop_lcd(fbinfo);
	msleep(1);

	nuc900fb_unmap_video_memory(fbinfo);

	iounmap(fbi->io);

	irq = platform_get_irq(pdev, 0);
	free_irq(irq, fbi);

	release_resource(fbi->mem);
	kfree(fbi->mem);

	platform_set_drvdata(pdev, NULL);
	framebuffer_release(fbinfo);

	return 0;
}

#ifdef CONFIG_PM

/*
 *	suspend and resume support for the lcd controller
 */

static int nuc900fb_suspend(struct platform_device *dev, pm_message_t state)
{
	struct fb_info	   *fbinfo = platform_get_drvdata(dev);
	struct nuc900fb_info *info = fbinfo->par;

	nuc900fb_stop_lcd();
	msleep(1);
	clk_disable(info->clk);
	return 0;
}

static int nuc900fb_resume(struct platform_device *dev)
{
	struct fb_info	   *fbinfo = platform_get_drvdata(dev);
	struct nuc900fb_info *fbi = fbinfo->par;

	printk(KERN_INFO "nuc900fb resume\n");

	clk_enable(fbi->clk);
	msleep(1);

	nuc900fb_init_registers(fbinfo);
	nuc900fb_activate_var(bfinfo);

	return 0;
}

#else
#define nuc900fb_suspend NULL
#define nuc900fb_resume  NULL
#endif

static struct platform_driver nuc900fb_driver = {
	.probe		= nuc900fb_probe,
	.remove		= nuc900fb_remove,
	.suspend	= nuc900fb_suspend,
	.resume		= nuc900fb_resume,
	.driver		= {
		.name	= "nuc900-lcd",
		.owner	= THIS_MODULE,
	},
};

int __devinit nuc900fb_init(void)
{
	return platform_driver_register(&nuc900fb_driver);
}

static void __exit nuc900fb_cleanup(void)
{
	platform_driver_unregister(&nuc900fb_driver);
}

module_init(nuc900fb_init);
module_exit(nuc900fb_cleanup);

MODULE_DESCRIPTION("Framebuffer driver for the NUC900");
MODULE_LICENSE("GPL");