xref: /linux/drivers/video/fbdev/imxfb.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 /*
2  *  Freescale i.MX Frame Buffer device driver
3  *
4  *  Copyright (C) 2004 Sascha Hauer, Pengutronix
5  *   Based on acornfb.c Copyright (C) Russell King.
6  *
7  * This file is subject to the terms and conditions of the GNU General Public
8  * License.  See the file COPYING in the main directory of this archive for
9  * more details.
10  *
11  * Please direct your questions and comments on this driver to the following
12  * email address:
13  *
14  *	linux-arm-kernel@lists.arm.linux.org.uk
15  */
16 
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/string.h>
21 #include <linux/interrupt.h>
22 #include <linux/slab.h>
23 #include <linux/mm.h>
24 #include <linux/fb.h>
25 #include <linux/delay.h>
26 #include <linux/init.h>
27 #include <linux/ioport.h>
28 #include <linux/cpufreq.h>
29 #include <linux/clk.h>
30 #include <linux/platform_device.h>
31 #include <linux/dma-mapping.h>
32 #include <linux/io.h>
33 #include <linux/lcd.h>
34 #include <linux/math64.h>
35 #include <linux/of.h>
36 #include <linux/of_device.h>
37 
38 #include <linux/regulator/consumer.h>
39 
40 #include <video/of_display_timing.h>
41 #include <video/of_videomode.h>
42 #include <video/videomode.h>
43 
44 #include <linux/platform_data/video-imxfb.h>
45 
46 /*
47  * Complain if VAR is out of range.
48  */
49 #define DEBUG_VAR 1
50 
51 #define DRIVER_NAME "imx-fb"
52 
53 #define LCDC_SSA	0x00
54 
55 #define LCDC_SIZE	0x04
56 #define SIZE_XMAX(x)	((((x) >> 4) & 0x3f) << 20)
57 
58 #define YMAX_MASK_IMX1	0x1ff
59 #define YMAX_MASK_IMX21	0x3ff
60 
61 #define LCDC_VPW	0x08
62 #define VPW_VPW(x)	((x) & 0x3ff)
63 
64 #define LCDC_CPOS	0x0C
65 #define CPOS_CC1	(1<<31)
66 #define CPOS_CC0	(1<<30)
67 #define CPOS_OP		(1<<28)
68 #define CPOS_CXP(x)	(((x) & 3ff) << 16)
69 
70 #define LCDC_LCWHB	0x10
71 #define LCWHB_BK_EN	(1<<31)
72 #define LCWHB_CW(w)	(((w) & 0x1f) << 24)
73 #define LCWHB_CH(h)	(((h) & 0x1f) << 16)
74 #define LCWHB_BD(x)	((x) & 0xff)
75 
76 #define LCDC_LCHCC	0x14
77 
78 #define LCDC_PCR	0x18
79 
80 #define LCDC_HCR	0x1C
81 #define HCR_H_WIDTH(x)	(((x) & 0x3f) << 26)
82 #define HCR_H_WAIT_1(x)	(((x) & 0xff) << 8)
83 #define HCR_H_WAIT_2(x)	((x) & 0xff)
84 
85 #define LCDC_VCR	0x20
86 #define VCR_V_WIDTH(x)	(((x) & 0x3f) << 26)
87 #define VCR_V_WAIT_1(x)	(((x) & 0xff) << 8)
88 #define VCR_V_WAIT_2(x)	((x) & 0xff)
89 
90 #define LCDC_POS	0x24
91 #define POS_POS(x)	((x) & 1f)
92 
93 #define LCDC_LSCR1	0x28
94 /* bit fields in imxfb.h */
95 
96 #define LCDC_PWMR	0x2C
97 /* bit fields in imxfb.h */
98 
99 #define LCDC_DMACR	0x30
100 /* bit fields in imxfb.h */
101 
102 #define LCDC_RMCR	0x34
103 
104 #define RMCR_LCDC_EN_MX1	(1<<1)
105 
106 #define RMCR_SELF_REF	(1<<0)
107 
108 #define LCDC_LCDICR	0x38
109 #define LCDICR_INT_SYN	(1<<2)
110 #define LCDICR_INT_CON	(1)
111 
112 #define LCDC_LCDISR	0x40
113 #define LCDISR_UDR_ERR	(1<<3)
114 #define LCDISR_ERR_RES	(1<<2)
115 #define LCDISR_EOF	(1<<1)
116 #define LCDISR_BOF	(1<<0)
117 
118 #define IMXFB_LSCR1_DEFAULT 0x00120300
119 
120 #define LCDC_LAUSCR	0x80
121 #define LAUSCR_AUS_MODE	(1<<31)
122 
123 /* Used fb-mode. Can be set on kernel command line, therefore file-static. */
124 static const char *fb_mode;
125 
126 /*
127  * These are the bitfields for each
128  * display depth that we support.
129  */
130 struct imxfb_rgb {
131 	struct fb_bitfield	red;
132 	struct fb_bitfield	green;
133 	struct fb_bitfield	blue;
134 	struct fb_bitfield	transp;
135 };
136 
137 enum imxfb_type {
138 	IMX1_FB,
139 	IMX21_FB,
140 };
141 
142 struct imxfb_info {
143 	struct platform_device  *pdev;
144 	void __iomem		*regs;
145 	struct clk		*clk_ipg;
146 	struct clk		*clk_ahb;
147 	struct clk		*clk_per;
148 	enum imxfb_type		devtype;
149 	bool			enabled;
150 
151 	/*
152 	 * These are the addresses we mapped
153 	 * the framebuffer memory region to.
154 	 */
155 	dma_addr_t		map_dma;
156 	u_int			map_size;
157 
158 	u_int			palette_size;
159 
160 	dma_addr_t		dbar1;
161 	dma_addr_t		dbar2;
162 
163 	u_int			pcr;
164 	u_int			lauscr;
165 	u_int			pwmr;
166 	u_int			lscr1;
167 	u_int			dmacr;
168 	bool			cmap_inverse;
169 	bool			cmap_static;
170 
171 	struct imx_fb_videomode *mode;
172 	int			num_modes;
173 
174 	struct regulator	*lcd_pwr;
175 	int			lcd_pwr_enabled;
176 };
177 
178 static const struct platform_device_id imxfb_devtype[] = {
179 	{
180 		.name = "imx1-fb",
181 		.driver_data = IMX1_FB,
182 	}, {
183 		.name = "imx21-fb",
184 		.driver_data = IMX21_FB,
185 	}, {
186 		/* sentinel */
187 	}
188 };
189 MODULE_DEVICE_TABLE(platform, imxfb_devtype);
190 
191 static const struct of_device_id imxfb_of_dev_id[] = {
192 	{
193 		.compatible = "fsl,imx1-fb",
194 		.data = &imxfb_devtype[IMX1_FB],
195 	}, {
196 		.compatible = "fsl,imx21-fb",
197 		.data = &imxfb_devtype[IMX21_FB],
198 	}, {
199 		/* sentinel */
200 	}
201 };
202 MODULE_DEVICE_TABLE(of, imxfb_of_dev_id);
203 
204 static inline int is_imx1_fb(struct imxfb_info *fbi)
205 {
206 	return fbi->devtype == IMX1_FB;
207 }
208 
209 #define IMX_NAME	"IMX"
210 
211 /*
212  * Minimum X and Y resolutions
213  */
214 #define MIN_XRES	64
215 #define MIN_YRES	64
216 
217 /* Actually this really is 18bit support, the lowest 2 bits of each colour
218  * are unused in hardware. We claim to have 24bit support to make software
219  * like X work, which does not support 18bit.
220  */
221 static struct imxfb_rgb def_rgb_18 = {
222 	.red	= {.offset = 16, .length = 8,},
223 	.green	= {.offset = 8, .length = 8,},
224 	.blue	= {.offset = 0, .length = 8,},
225 	.transp = {.offset = 0, .length = 0,},
226 };
227 
228 static struct imxfb_rgb def_rgb_16_tft = {
229 	.red	= {.offset = 11, .length = 5,},
230 	.green	= {.offset = 5, .length = 6,},
231 	.blue	= {.offset = 0, .length = 5,},
232 	.transp = {.offset = 0, .length = 0,},
233 };
234 
235 static struct imxfb_rgb def_rgb_16_stn = {
236 	.red	= {.offset = 8, .length = 4,},
237 	.green	= {.offset = 4, .length = 4,},
238 	.blue	= {.offset = 0, .length = 4,},
239 	.transp = {.offset = 0, .length = 0,},
240 };
241 
242 static struct imxfb_rgb def_rgb_8 = {
243 	.red	= {.offset = 0, .length = 8,},
244 	.green	= {.offset = 0, .length = 8,},
245 	.blue	= {.offset = 0, .length = 8,},
246 	.transp = {.offset = 0, .length = 0,},
247 };
248 
249 static int imxfb_activate_var(struct fb_var_screeninfo *var,
250 		struct fb_info *info);
251 
252 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
253 {
254 	chan &= 0xffff;
255 	chan >>= 16 - bf->length;
256 	return chan << bf->offset;
257 }
258 
259 static int imxfb_setpalettereg(u_int regno, u_int red, u_int green, u_int blue,
260 		u_int trans, struct fb_info *info)
261 {
262 	struct imxfb_info *fbi = info->par;
263 	u_int val, ret = 1;
264 
265 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
266 	if (regno < fbi->palette_size) {
267 		val = (CNVT_TOHW(red, 4) << 8) |
268 		      (CNVT_TOHW(green,4) << 4) |
269 		      CNVT_TOHW(blue,  4);
270 
271 		writel(val, fbi->regs + 0x800 + (regno << 2));
272 		ret = 0;
273 	}
274 	return ret;
275 }
276 
277 static int imxfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
278 		   u_int trans, struct fb_info *info)
279 {
280 	struct imxfb_info *fbi = info->par;
281 	unsigned int val;
282 	int ret = 1;
283 
284 	/*
285 	 * If inverse mode was selected, invert all the colours
286 	 * rather than the register number.  The register number
287 	 * is what you poke into the framebuffer to produce the
288 	 * colour you requested.
289 	 */
290 	if (fbi->cmap_inverse) {
291 		red   = 0xffff - red;
292 		green = 0xffff - green;
293 		blue  = 0xffff - blue;
294 	}
295 
296 	/*
297 	 * If greyscale is true, then we convert the RGB value
298 	 * to greyscale no mater what visual we are using.
299 	 */
300 	if (info->var.grayscale)
301 		red = green = blue = (19595 * red + 38470 * green +
302 					7471 * blue) >> 16;
303 
304 	switch (info->fix.visual) {
305 	case FB_VISUAL_TRUECOLOR:
306 		/*
307 		 * 12 or 16-bit True Colour.  We encode the RGB value
308 		 * according to the RGB bitfield information.
309 		 */
310 		if (regno < 16) {
311 			u32 *pal = info->pseudo_palette;
312 
313 			val  = chan_to_field(red, &info->var.red);
314 			val |= chan_to_field(green, &info->var.green);
315 			val |= chan_to_field(blue, &info->var.blue);
316 
317 			pal[regno] = val;
318 			ret = 0;
319 		}
320 		break;
321 
322 	case FB_VISUAL_STATIC_PSEUDOCOLOR:
323 	case FB_VISUAL_PSEUDOCOLOR:
324 		ret = imxfb_setpalettereg(regno, red, green, blue, trans, info);
325 		break;
326 	}
327 
328 	return ret;
329 }
330 
331 static const struct imx_fb_videomode *imxfb_find_mode(struct imxfb_info *fbi)
332 {
333 	struct imx_fb_videomode *m;
334 	int i;
335 
336 	if (!fb_mode)
337 		return &fbi->mode[0];
338 
339 	for (i = 0, m = &fbi->mode[0]; i < fbi->num_modes; i++, m++) {
340 		if (!strcmp(m->mode.name, fb_mode))
341 			return m;
342 	}
343 	return NULL;
344 }
345 
346 /*
347  *  imxfb_check_var():
348  *    Round up in the following order: bits_per_pixel, xres,
349  *    yres, xres_virtual, yres_virtual, xoffset, yoffset, grayscale,
350  *    bitfields, horizontal timing, vertical timing.
351  */
352 static int imxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
353 {
354 	struct imxfb_info *fbi = info->par;
355 	struct imxfb_rgb *rgb;
356 	const struct imx_fb_videomode *imxfb_mode;
357 	unsigned long lcd_clk;
358 	unsigned long long tmp;
359 	u32 pcr = 0;
360 
361 	if (var->xres < MIN_XRES)
362 		var->xres = MIN_XRES;
363 	if (var->yres < MIN_YRES)
364 		var->yres = MIN_YRES;
365 
366 	imxfb_mode = imxfb_find_mode(fbi);
367 	if (!imxfb_mode)
368 		return -EINVAL;
369 
370 	var->xres		= imxfb_mode->mode.xres;
371 	var->yres		= imxfb_mode->mode.yres;
372 	var->bits_per_pixel	= imxfb_mode->bpp;
373 	var->pixclock		= imxfb_mode->mode.pixclock;
374 	var->hsync_len		= imxfb_mode->mode.hsync_len;
375 	var->left_margin	= imxfb_mode->mode.left_margin;
376 	var->right_margin	= imxfb_mode->mode.right_margin;
377 	var->vsync_len		= imxfb_mode->mode.vsync_len;
378 	var->upper_margin	= imxfb_mode->mode.upper_margin;
379 	var->lower_margin	= imxfb_mode->mode.lower_margin;
380 	var->sync		= imxfb_mode->mode.sync;
381 	var->xres_virtual	= max(var->xres_virtual, var->xres);
382 	var->yres_virtual	= max(var->yres_virtual, var->yres);
383 
384 	pr_debug("var->bits_per_pixel=%d\n", var->bits_per_pixel);
385 
386 	lcd_clk = clk_get_rate(fbi->clk_per);
387 
388 	tmp = var->pixclock * (unsigned long long)lcd_clk;
389 
390 	do_div(tmp, 1000000);
391 
392 	if (do_div(tmp, 1000000) > 500000)
393 		tmp++;
394 
395 	pcr = (unsigned int)tmp;
396 
397 	if (--pcr > 0x3F) {
398 		pcr = 0x3F;
399 		printk(KERN_WARNING "Must limit pixel clock to %luHz\n",
400 				lcd_clk / pcr);
401 	}
402 
403 	switch (var->bits_per_pixel) {
404 	case 32:
405 		pcr |= PCR_BPIX_18;
406 		rgb = &def_rgb_18;
407 		break;
408 	case 16:
409 	default:
410 		if (is_imx1_fb(fbi))
411 			pcr |= PCR_BPIX_12;
412 		else
413 			pcr |= PCR_BPIX_16;
414 
415 		if (imxfb_mode->pcr & PCR_TFT)
416 			rgb = &def_rgb_16_tft;
417 		else
418 			rgb = &def_rgb_16_stn;
419 		break;
420 	case 8:
421 		pcr |= PCR_BPIX_8;
422 		rgb = &def_rgb_8;
423 		break;
424 	}
425 
426 	/* add sync polarities */
427 	pcr |= imxfb_mode->pcr & ~(0x3f | (7 << 25));
428 
429 	fbi->pcr = pcr;
430 	/*
431 	 * The LCDC AUS Mode Control Register does not exist on imx1.
432 	 */
433 	if (!is_imx1_fb(fbi) && imxfb_mode->aus_mode)
434 		fbi->lauscr = LAUSCR_AUS_MODE;
435 
436 	/*
437 	 * Copy the RGB parameters for this display
438 	 * from the machine specific parameters.
439 	 */
440 	var->red    = rgb->red;
441 	var->green  = rgb->green;
442 	var->blue   = rgb->blue;
443 	var->transp = rgb->transp;
444 
445 	pr_debug("RGBT length = %d:%d:%d:%d\n",
446 		var->red.length, var->green.length, var->blue.length,
447 		var->transp.length);
448 
449 	pr_debug("RGBT offset = %d:%d:%d:%d\n",
450 		var->red.offset, var->green.offset, var->blue.offset,
451 		var->transp.offset);
452 
453 	return 0;
454 }
455 
456 /*
457  * imxfb_set_par():
458  *	Set the user defined part of the display for the specified console
459  */
460 static int imxfb_set_par(struct fb_info *info)
461 {
462 	struct imxfb_info *fbi = info->par;
463 	struct fb_var_screeninfo *var = &info->var;
464 
465 	if (var->bits_per_pixel == 16 || var->bits_per_pixel == 32)
466 		info->fix.visual = FB_VISUAL_TRUECOLOR;
467 	else if (!fbi->cmap_static)
468 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
469 	else {
470 		/*
471 		 * Some people have weird ideas about wanting static
472 		 * pseudocolor maps.  I suspect their user space
473 		 * applications are broken.
474 		 */
475 		info->fix.visual = FB_VISUAL_STATIC_PSEUDOCOLOR;
476 	}
477 
478 	info->fix.line_length = var->xres_virtual * var->bits_per_pixel / 8;
479 	fbi->palette_size = var->bits_per_pixel == 8 ? 256 : 16;
480 
481 	imxfb_activate_var(var, info);
482 
483 	return 0;
484 }
485 
486 static int imxfb_enable_controller(struct imxfb_info *fbi)
487 {
488 	int ret;
489 
490 	if (fbi->enabled)
491 		return 0;
492 
493 	pr_debug("Enabling LCD controller\n");
494 
495 	writel(fbi->map_dma, fbi->regs + LCDC_SSA);
496 
497 	/* panning offset 0 (0 pixel offset)        */
498 	writel(0x00000000, fbi->regs + LCDC_POS);
499 
500 	/* disable hardware cursor */
501 	writel(readl(fbi->regs + LCDC_CPOS) & ~(CPOS_CC0 | CPOS_CC1),
502 		fbi->regs + LCDC_CPOS);
503 
504 	/*
505 	 * RMCR_LCDC_EN_MX1 is present on i.MX1 only, but doesn't hurt
506 	 * on other SoCs
507 	 */
508 	writel(RMCR_LCDC_EN_MX1, fbi->regs + LCDC_RMCR);
509 
510 	ret = clk_prepare_enable(fbi->clk_ipg);
511 	if (ret)
512 		goto err_enable_ipg;
513 
514 	ret = clk_prepare_enable(fbi->clk_ahb);
515 	if (ret)
516 		goto err_enable_ahb;
517 
518 	ret = clk_prepare_enable(fbi->clk_per);
519 	if (ret)
520 		goto err_enable_per;
521 
522 	fbi->enabled = true;
523 	return 0;
524 
525 err_enable_per:
526 	clk_disable_unprepare(fbi->clk_ahb);
527 err_enable_ahb:
528 	clk_disable_unprepare(fbi->clk_ipg);
529 err_enable_ipg:
530 	writel(0, fbi->regs + LCDC_RMCR);
531 
532 	return ret;
533 }
534 
535 static void imxfb_disable_controller(struct imxfb_info *fbi)
536 {
537 	if (!fbi->enabled)
538 		return;
539 
540 	pr_debug("Disabling LCD controller\n");
541 
542 	clk_disable_unprepare(fbi->clk_per);
543 	clk_disable_unprepare(fbi->clk_ahb);
544 	clk_disable_unprepare(fbi->clk_ipg);
545 	fbi->enabled = false;
546 
547 	writel(0, fbi->regs + LCDC_RMCR);
548 }
549 
550 static int imxfb_blank(int blank, struct fb_info *info)
551 {
552 	struct imxfb_info *fbi = info->par;
553 
554 	pr_debug("imxfb_blank: blank=%d\n", blank);
555 
556 	switch (blank) {
557 	case FB_BLANK_POWERDOWN:
558 	case FB_BLANK_VSYNC_SUSPEND:
559 	case FB_BLANK_HSYNC_SUSPEND:
560 	case FB_BLANK_NORMAL:
561 		imxfb_disable_controller(fbi);
562 		break;
563 
564 	case FB_BLANK_UNBLANK:
565 		return imxfb_enable_controller(fbi);
566 	}
567 	return 0;
568 }
569 
570 static const struct fb_ops imxfb_ops = {
571 	.owner		= THIS_MODULE,
572 	.fb_check_var	= imxfb_check_var,
573 	.fb_set_par	= imxfb_set_par,
574 	.fb_setcolreg	= imxfb_setcolreg,
575 	.fb_fillrect	= cfb_fillrect,
576 	.fb_copyarea	= cfb_copyarea,
577 	.fb_imageblit	= cfb_imageblit,
578 	.fb_blank	= imxfb_blank,
579 };
580 
581 /*
582  * imxfb_activate_var():
583  *	Configures LCD Controller based on entries in var parameter.  Settings are
584  *	only written to the controller if changes were made.
585  */
586 static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *info)
587 {
588 	struct imxfb_info *fbi = info->par;
589 	u32 ymax_mask = is_imx1_fb(fbi) ? YMAX_MASK_IMX1 : YMAX_MASK_IMX21;
590 
591 	pr_debug("var: xres=%d hslen=%d lm=%d rm=%d\n",
592 		var->xres, var->hsync_len,
593 		var->left_margin, var->right_margin);
594 	pr_debug("var: yres=%d vslen=%d um=%d bm=%d\n",
595 		var->yres, var->vsync_len,
596 		var->upper_margin, var->lower_margin);
597 
598 #if DEBUG_VAR
599 	if (var->xres < 16        || var->xres > 1024)
600 		printk(KERN_ERR "%s: invalid xres %d\n",
601 			info->fix.id, var->xres);
602 	if (var->hsync_len < 1    || var->hsync_len > 64)
603 		printk(KERN_ERR "%s: invalid hsync_len %d\n",
604 			info->fix.id, var->hsync_len);
605 	if (var->left_margin > 255)
606 		printk(KERN_ERR "%s: invalid left_margin %d\n",
607 			info->fix.id, var->left_margin);
608 	if (var->right_margin > 255)
609 		printk(KERN_ERR "%s: invalid right_margin %d\n",
610 			info->fix.id, var->right_margin);
611 	if (var->yres < 1 || var->yres > ymax_mask)
612 		printk(KERN_ERR "%s: invalid yres %d\n",
613 			info->fix.id, var->yres);
614 	if (var->vsync_len > 100)
615 		printk(KERN_ERR "%s: invalid vsync_len %d\n",
616 			info->fix.id, var->vsync_len);
617 	if (var->upper_margin > 63)
618 		printk(KERN_ERR "%s: invalid upper_margin %d\n",
619 			info->fix.id, var->upper_margin);
620 	if (var->lower_margin > 255)
621 		printk(KERN_ERR "%s: invalid lower_margin %d\n",
622 			info->fix.id, var->lower_margin);
623 #endif
624 
625 	/* physical screen start address	    */
626 	writel(VPW_VPW(var->xres * var->bits_per_pixel / 8 / 4),
627 		fbi->regs + LCDC_VPW);
628 
629 	writel(HCR_H_WIDTH(var->hsync_len - 1) |
630 		HCR_H_WAIT_1(var->right_margin - 1) |
631 		HCR_H_WAIT_2(var->left_margin - 3),
632 		fbi->regs + LCDC_HCR);
633 
634 	writel(VCR_V_WIDTH(var->vsync_len) |
635 		VCR_V_WAIT_1(var->lower_margin) |
636 		VCR_V_WAIT_2(var->upper_margin),
637 		fbi->regs + LCDC_VCR);
638 
639 	writel(SIZE_XMAX(var->xres) | (var->yres & ymax_mask),
640 			fbi->regs + LCDC_SIZE);
641 
642 	writel(fbi->pcr, fbi->regs + LCDC_PCR);
643 	if (fbi->pwmr)
644 		writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
645 	writel(fbi->lscr1, fbi->regs + LCDC_LSCR1);
646 
647 	/* dmacr = 0 is no valid value, as we need DMA control marks. */
648 	if (fbi->dmacr)
649 		writel(fbi->dmacr, fbi->regs + LCDC_DMACR);
650 
651 	if (fbi->lauscr)
652 		writel(fbi->lauscr, fbi->regs + LCDC_LAUSCR);
653 
654 	return 0;
655 }
656 
657 static int imxfb_init_fbinfo(struct platform_device *pdev)
658 {
659 	struct imx_fb_platform_data *pdata = dev_get_platdata(&pdev->dev);
660 	struct fb_info *info = platform_get_drvdata(pdev);
661 	struct imxfb_info *fbi = info->par;
662 	struct device_node *np;
663 
664 	pr_debug("%s\n",__func__);
665 
666 	info->pseudo_palette = kmalloc_array(16, sizeof(u32), GFP_KERNEL);
667 	if (!info->pseudo_palette)
668 		return -ENOMEM;
669 
670 	memset(fbi, 0, sizeof(struct imxfb_info));
671 
672 	fbi->devtype = pdev->id_entry->driver_data;
673 
674 	strlcpy(info->fix.id, IMX_NAME, sizeof(info->fix.id));
675 
676 	info->fix.type			= FB_TYPE_PACKED_PIXELS;
677 	info->fix.type_aux		= 0;
678 	info->fix.xpanstep		= 0;
679 	info->fix.ypanstep		= 0;
680 	info->fix.ywrapstep		= 0;
681 	info->fix.accel			= FB_ACCEL_NONE;
682 
683 	info->var.nonstd		= 0;
684 	info->var.activate		= FB_ACTIVATE_NOW;
685 	info->var.height		= -1;
686 	info->var.width	= -1;
687 	info->var.accel_flags		= 0;
688 	info->var.vmode			= FB_VMODE_NONINTERLACED;
689 
690 	info->fbops			= &imxfb_ops;
691 	info->flags			= FBINFO_FLAG_DEFAULT |
692 					  FBINFO_READS_FAST;
693 	if (pdata) {
694 		fbi->lscr1			= pdata->lscr1;
695 		fbi->dmacr			= pdata->dmacr;
696 		fbi->pwmr			= pdata->pwmr;
697 	} else {
698 		np = pdev->dev.of_node;
699 		info->var.grayscale = of_property_read_bool(np,
700 						"cmap-greyscale");
701 		fbi->cmap_inverse = of_property_read_bool(np, "cmap-inverse");
702 		fbi->cmap_static = of_property_read_bool(np, "cmap-static");
703 
704 		fbi->lscr1 = IMXFB_LSCR1_DEFAULT;
705 
706 		of_property_read_u32(np, "fsl,lpccr", &fbi->pwmr);
707 
708 		of_property_read_u32(np, "fsl,lscr1", &fbi->lscr1);
709 
710 		of_property_read_u32(np, "fsl,dmacr", &fbi->dmacr);
711 	}
712 
713 	return 0;
714 }
715 
716 static int imxfb_of_read_mode(struct device *dev, struct device_node *np,
717 		struct imx_fb_videomode *imxfb_mode)
718 {
719 	int ret;
720 	struct fb_videomode *of_mode = &imxfb_mode->mode;
721 	u32 bpp;
722 	u32 pcr;
723 
724 	ret = of_property_read_string(np, "model", &of_mode->name);
725 	if (ret)
726 		of_mode->name = NULL;
727 
728 	ret = of_get_fb_videomode(np, of_mode, OF_USE_NATIVE_MODE);
729 	if (ret) {
730 		dev_err(dev, "Failed to get videomode from DT\n");
731 		return ret;
732 	}
733 
734 	ret = of_property_read_u32(np, "bits-per-pixel", &bpp);
735 	ret |= of_property_read_u32(np, "fsl,pcr", &pcr);
736 
737 	if (ret) {
738 		dev_err(dev, "Failed to read bpp and pcr from DT\n");
739 		return -EINVAL;
740 	}
741 
742 	if (bpp < 1 || bpp > 255) {
743 		dev_err(dev, "Bits per pixel have to be between 1 and 255\n");
744 		return -EINVAL;
745 	}
746 
747 	imxfb_mode->bpp = bpp;
748 	imxfb_mode->pcr = pcr;
749 
750 	/*
751 	 * fsl,aus-mode is optional
752 	 */
753 	imxfb_mode->aus_mode = of_property_read_bool(np, "fsl,aus-mode");
754 
755 	return 0;
756 }
757 
758 static int imxfb_lcd_check_fb(struct lcd_device *lcddev, struct fb_info *fi)
759 {
760 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
761 
762 	if (!fi || fi->par == fbi)
763 		return 1;
764 
765 	return 0;
766 }
767 
768 static int imxfb_lcd_get_contrast(struct lcd_device *lcddev)
769 {
770 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
771 
772 	return fbi->pwmr & 0xff;
773 }
774 
775 static int imxfb_lcd_set_contrast(struct lcd_device *lcddev, int contrast)
776 {
777 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
778 
779 	if (fbi->pwmr && fbi->enabled) {
780 		if (contrast > 255)
781 			contrast = 255;
782 		else if (contrast < 0)
783 			contrast = 0;
784 
785 		fbi->pwmr &= ~0xff;
786 		fbi->pwmr |= contrast;
787 
788 		writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
789 	}
790 
791 	return 0;
792 }
793 
794 static int imxfb_lcd_get_power(struct lcd_device *lcddev)
795 {
796 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
797 
798 	if (!IS_ERR(fbi->lcd_pwr) &&
799 	    !regulator_is_enabled(fbi->lcd_pwr))
800 		return FB_BLANK_POWERDOWN;
801 
802 	return FB_BLANK_UNBLANK;
803 }
804 
805 static int imxfb_regulator_set(struct imxfb_info *fbi, int enable)
806 {
807 	int ret;
808 
809 	if (enable == fbi->lcd_pwr_enabled)
810 		return 0;
811 
812 	if (enable)
813 		ret = regulator_enable(fbi->lcd_pwr);
814 	else
815 		ret = regulator_disable(fbi->lcd_pwr);
816 
817 	if (ret == 0)
818 		fbi->lcd_pwr_enabled = enable;
819 
820 	return ret;
821 }
822 
823 static int imxfb_lcd_set_power(struct lcd_device *lcddev, int power)
824 {
825 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
826 
827 	if (!IS_ERR(fbi->lcd_pwr))
828 		return imxfb_regulator_set(fbi, power == FB_BLANK_UNBLANK);
829 
830 	return 0;
831 }
832 
833 static struct lcd_ops imxfb_lcd_ops = {
834 	.check_fb	= imxfb_lcd_check_fb,
835 	.get_contrast	= imxfb_lcd_get_contrast,
836 	.set_contrast	= imxfb_lcd_set_contrast,
837 	.get_power	= imxfb_lcd_get_power,
838 	.set_power	= imxfb_lcd_set_power,
839 };
840 
841 static int imxfb_setup(void)
842 {
843 	char *opt, *options = NULL;
844 
845 	if (fb_get_options("imxfb", &options))
846 		return -ENODEV;
847 
848 	if (!options || !*options)
849 		return 0;
850 
851 	while ((opt = strsep(&options, ",")) != NULL) {
852 		if (!*opt)
853 			continue;
854 		else
855 			fb_mode = opt;
856 	}
857 
858 	return 0;
859 }
860 
861 static int imxfb_probe(struct platform_device *pdev)
862 {
863 	struct imxfb_info *fbi;
864 	struct lcd_device *lcd;
865 	struct fb_info *info;
866 	struct imx_fb_platform_data *pdata;
867 	struct resource *res;
868 	struct imx_fb_videomode *m;
869 	const struct of_device_id *of_id;
870 	int ret, i;
871 	int bytes_per_pixel;
872 
873 	dev_info(&pdev->dev, "i.MX Framebuffer driver\n");
874 
875 	ret = imxfb_setup();
876 	if (ret < 0)
877 		return ret;
878 
879 	of_id = of_match_device(imxfb_of_dev_id, &pdev->dev);
880 	if (of_id)
881 		pdev->id_entry = of_id->data;
882 
883 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
884 	if (!res)
885 		return -ENODEV;
886 
887 	pdata = dev_get_platdata(&pdev->dev);
888 
889 	info = framebuffer_alloc(sizeof(struct imxfb_info), &pdev->dev);
890 	if (!info)
891 		return -ENOMEM;
892 
893 	fbi = info->par;
894 
895 	platform_set_drvdata(pdev, info);
896 
897 	ret = imxfb_init_fbinfo(pdev);
898 	if (ret < 0)
899 		goto failed_init;
900 
901 	if (pdata) {
902 		if (!fb_mode)
903 			fb_mode = pdata->mode[0].mode.name;
904 
905 		fbi->mode = pdata->mode;
906 		fbi->num_modes = pdata->num_modes;
907 	} else {
908 		struct device_node *display_np;
909 		fb_mode = NULL;
910 
911 		display_np = of_parse_phandle(pdev->dev.of_node, "display", 0);
912 		if (!display_np) {
913 			dev_err(&pdev->dev, "No display defined in devicetree\n");
914 			ret = -EINVAL;
915 			goto failed_of_parse;
916 		}
917 
918 		/*
919 		 * imxfb does not support more modes, we choose only the native
920 		 * mode.
921 		 */
922 		fbi->num_modes = 1;
923 
924 		fbi->mode = devm_kzalloc(&pdev->dev,
925 				sizeof(struct imx_fb_videomode), GFP_KERNEL);
926 		if (!fbi->mode) {
927 			ret = -ENOMEM;
928 			of_node_put(display_np);
929 			goto failed_of_parse;
930 		}
931 
932 		ret = imxfb_of_read_mode(&pdev->dev, display_np, fbi->mode);
933 		of_node_put(display_np);
934 		if (ret)
935 			goto failed_of_parse;
936 	}
937 
938 	/* Calculate maximum bytes used per pixel. In most cases this should
939 	 * be the same as m->bpp/8 */
940 	m = &fbi->mode[0];
941 	bytes_per_pixel = (m->bpp + 7) / 8;
942 	for (i = 0; i < fbi->num_modes; i++, m++)
943 		info->fix.smem_len = max_t(size_t, info->fix.smem_len,
944 				m->mode.xres * m->mode.yres * bytes_per_pixel);
945 
946 	res = request_mem_region(res->start, resource_size(res),
947 				DRIVER_NAME);
948 	if (!res) {
949 		ret = -EBUSY;
950 		goto failed_req;
951 	}
952 
953 	fbi->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
954 	if (IS_ERR(fbi->clk_ipg)) {
955 		ret = PTR_ERR(fbi->clk_ipg);
956 		goto failed_getclock;
957 	}
958 
959 	/*
960 	 * The LCDC controller does not have an enable bit. The
961 	 * controller starts directly when the clocks are enabled.
962 	 * If the clocks are enabled when the controller is not yet
963 	 * programmed with proper register values (enabled at the
964 	 * bootloader, for example) then it just goes into some undefined
965 	 * state.
966 	 * To avoid this issue, let's enable and disable LCDC IPG clock
967 	 * so that we force some kind of 'reset' to the LCDC block.
968 	 */
969 	ret = clk_prepare_enable(fbi->clk_ipg);
970 	if (ret)
971 		goto failed_getclock;
972 	clk_disable_unprepare(fbi->clk_ipg);
973 
974 	fbi->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
975 	if (IS_ERR(fbi->clk_ahb)) {
976 		ret = PTR_ERR(fbi->clk_ahb);
977 		goto failed_getclock;
978 	}
979 
980 	fbi->clk_per = devm_clk_get(&pdev->dev, "per");
981 	if (IS_ERR(fbi->clk_per)) {
982 		ret = PTR_ERR(fbi->clk_per);
983 		goto failed_getclock;
984 	}
985 
986 	fbi->regs = ioremap(res->start, resource_size(res));
987 	if (fbi->regs == NULL) {
988 		dev_err(&pdev->dev, "Cannot map frame buffer registers\n");
989 		ret = -ENOMEM;
990 		goto failed_ioremap;
991 	}
992 
993 	fbi->map_size = PAGE_ALIGN(info->fix.smem_len);
994 	info->screen_buffer = dma_alloc_wc(&pdev->dev, fbi->map_size,
995 					   &fbi->map_dma, GFP_KERNEL);
996 	if (!info->screen_buffer) {
997 		dev_err(&pdev->dev, "Failed to allocate video RAM\n");
998 		ret = -ENOMEM;
999 		goto failed_map;
1000 	}
1001 
1002 	info->fix.smem_start = fbi->map_dma;
1003 
1004 	if (pdata && pdata->init) {
1005 		ret = pdata->init(fbi->pdev);
1006 		if (ret)
1007 			goto failed_platform_init;
1008 	}
1009 
1010 
1011 	INIT_LIST_HEAD(&info->modelist);
1012 	for (i = 0; i < fbi->num_modes; i++)
1013 		fb_add_videomode(&fbi->mode[i].mode, &info->modelist);
1014 
1015 	/*
1016 	 * This makes sure that our colour bitfield
1017 	 * descriptors are correctly initialised.
1018 	 */
1019 	imxfb_check_var(&info->var, info);
1020 
1021 	/*
1022 	 * For modes > 8bpp, the color map is bypassed.
1023 	 * Therefore, 256 entries are enough.
1024 	 */
1025 	ret = fb_alloc_cmap(&info->cmap, 256, 0);
1026 	if (ret < 0)
1027 		goto failed_cmap;
1028 
1029 	imxfb_set_par(info);
1030 	ret = register_framebuffer(info);
1031 	if (ret < 0) {
1032 		dev_err(&pdev->dev, "failed to register framebuffer\n");
1033 		goto failed_register;
1034 	}
1035 
1036 	fbi->lcd_pwr = devm_regulator_get(&pdev->dev, "lcd");
1037 	if (PTR_ERR(fbi->lcd_pwr) == -EPROBE_DEFER) {
1038 		ret = -EPROBE_DEFER;
1039 		goto failed_lcd;
1040 	}
1041 
1042 	lcd = devm_lcd_device_register(&pdev->dev, "imxfb-lcd", &pdev->dev, fbi,
1043 				       &imxfb_lcd_ops);
1044 	if (IS_ERR(lcd)) {
1045 		ret = PTR_ERR(lcd);
1046 		goto failed_lcd;
1047 	}
1048 
1049 	lcd->props.max_contrast = 0xff;
1050 
1051 	imxfb_enable_controller(fbi);
1052 	fbi->pdev = pdev;
1053 
1054 	return 0;
1055 
1056 failed_lcd:
1057 	unregister_framebuffer(info);
1058 
1059 failed_register:
1060 	fb_dealloc_cmap(&info->cmap);
1061 failed_cmap:
1062 	if (pdata && pdata->exit)
1063 		pdata->exit(fbi->pdev);
1064 failed_platform_init:
1065 	dma_free_wc(&pdev->dev, fbi->map_size, info->screen_buffer,
1066 		    fbi->map_dma);
1067 failed_map:
1068 	iounmap(fbi->regs);
1069 failed_ioremap:
1070 failed_getclock:
1071 	release_mem_region(res->start, resource_size(res));
1072 failed_req:
1073 failed_of_parse:
1074 	kfree(info->pseudo_palette);
1075 failed_init:
1076 	framebuffer_release(info);
1077 	return ret;
1078 }
1079 
1080 static int imxfb_remove(struct platform_device *pdev)
1081 {
1082 	struct imx_fb_platform_data *pdata;
1083 	struct fb_info *info = platform_get_drvdata(pdev);
1084 	struct imxfb_info *fbi = info->par;
1085 	struct resource *res;
1086 
1087 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1088 	if (!res)
1089 		return -EINVAL;
1090 
1091 	imxfb_disable_controller(fbi);
1092 
1093 	unregister_framebuffer(info);
1094 	fb_dealloc_cmap(&info->cmap);
1095 	pdata = dev_get_platdata(&pdev->dev);
1096 	if (pdata && pdata->exit)
1097 		pdata->exit(fbi->pdev);
1098 	dma_free_wc(&pdev->dev, fbi->map_size, info->screen_buffer,
1099 		    fbi->map_dma);
1100 	iounmap(fbi->regs);
1101 	release_mem_region(res->start, resource_size(res));
1102 	kfree(info->pseudo_palette);
1103 	framebuffer_release(info);
1104 
1105 	return 0;
1106 }
1107 
1108 static int __maybe_unused imxfb_suspend(struct device *dev)
1109 {
1110 	struct fb_info *info = dev_get_drvdata(dev);
1111 	struct imxfb_info *fbi = info->par;
1112 
1113 	imxfb_disable_controller(fbi);
1114 
1115 	return 0;
1116 }
1117 
1118 static int __maybe_unused imxfb_resume(struct device *dev)
1119 {
1120 	struct fb_info *info = dev_get_drvdata(dev);
1121 	struct imxfb_info *fbi = info->par;
1122 
1123 	imxfb_enable_controller(fbi);
1124 
1125 	return 0;
1126 }
1127 
1128 static SIMPLE_DEV_PM_OPS(imxfb_pm_ops, imxfb_suspend, imxfb_resume);
1129 
1130 static struct platform_driver imxfb_driver = {
1131 	.driver		= {
1132 		.name	= DRIVER_NAME,
1133 		.of_match_table = imxfb_of_dev_id,
1134 		.pm	= &imxfb_pm_ops,
1135 	},
1136 	.probe		= imxfb_probe,
1137 	.remove		= imxfb_remove,
1138 	.id_table	= imxfb_devtype,
1139 };
1140 module_platform_driver(imxfb_driver);
1141 
1142 MODULE_DESCRIPTION("Freescale i.MX framebuffer driver");
1143 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1144 MODULE_LICENSE("GPL");
1145