xref: /openbmc/linux/drivers/video/fbdev/imxfb.c (revision d0e22329)
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 };
176 
177 static const struct platform_device_id imxfb_devtype[] = {
178 	{
179 		.name = "imx1-fb",
180 		.driver_data = IMX1_FB,
181 	}, {
182 		.name = "imx21-fb",
183 		.driver_data = IMX21_FB,
184 	}, {
185 		/* sentinel */
186 	}
187 };
188 MODULE_DEVICE_TABLE(platform, imxfb_devtype);
189 
190 static const struct of_device_id imxfb_of_dev_id[] = {
191 	{
192 		.compatible = "fsl,imx1-fb",
193 		.data = &imxfb_devtype[IMX1_FB],
194 	}, {
195 		.compatible = "fsl,imx21-fb",
196 		.data = &imxfb_devtype[IMX21_FB],
197 	}, {
198 		/* sentinel */
199 	}
200 };
201 MODULE_DEVICE_TABLE(of, imxfb_of_dev_id);
202 
203 static inline int is_imx1_fb(struct imxfb_info *fbi)
204 {
205 	return fbi->devtype == IMX1_FB;
206 }
207 
208 #define IMX_NAME	"IMX"
209 
210 /*
211  * Minimum X and Y resolutions
212  */
213 #define MIN_XRES	64
214 #define MIN_YRES	64
215 
216 /* Actually this really is 18bit support, the lowest 2 bits of each colour
217  * are unused in hardware. We claim to have 24bit support to make software
218  * like X work, which does not support 18bit.
219  */
220 static struct imxfb_rgb def_rgb_18 = {
221 	.red	= {.offset = 16, .length = 8,},
222 	.green	= {.offset = 8, .length = 8,},
223 	.blue	= {.offset = 0, .length = 8,},
224 	.transp = {.offset = 0, .length = 0,},
225 };
226 
227 static struct imxfb_rgb def_rgb_16_tft = {
228 	.red	= {.offset = 11, .length = 5,},
229 	.green	= {.offset = 5, .length = 6,},
230 	.blue	= {.offset = 0, .length = 5,},
231 	.transp = {.offset = 0, .length = 0,},
232 };
233 
234 static struct imxfb_rgb def_rgb_16_stn = {
235 	.red	= {.offset = 8, .length = 4,},
236 	.green	= {.offset = 4, .length = 4,},
237 	.blue	= {.offset = 0, .length = 4,},
238 	.transp = {.offset = 0, .length = 0,},
239 };
240 
241 static struct imxfb_rgb def_rgb_8 = {
242 	.red	= {.offset = 0, .length = 8,},
243 	.green	= {.offset = 0, .length = 8,},
244 	.blue	= {.offset = 0, .length = 8,},
245 	.transp = {.offset = 0, .length = 0,},
246 };
247 
248 static int imxfb_activate_var(struct fb_var_screeninfo *var,
249 		struct fb_info *info);
250 
251 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
252 {
253 	chan &= 0xffff;
254 	chan >>= 16 - bf->length;
255 	return chan << bf->offset;
256 }
257 
258 static int imxfb_setpalettereg(u_int regno, u_int red, u_int green, u_int blue,
259 		u_int trans, struct fb_info *info)
260 {
261 	struct imxfb_info *fbi = info->par;
262 	u_int val, ret = 1;
263 
264 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
265 	if (regno < fbi->palette_size) {
266 		val = (CNVT_TOHW(red, 4) << 8) |
267 		      (CNVT_TOHW(green,4) << 4) |
268 		      CNVT_TOHW(blue,  4);
269 
270 		writel(val, fbi->regs + 0x800 + (regno << 2));
271 		ret = 0;
272 	}
273 	return ret;
274 }
275 
276 static int imxfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
277 		   u_int trans, struct fb_info *info)
278 {
279 	struct imxfb_info *fbi = info->par;
280 	unsigned int val;
281 	int ret = 1;
282 
283 	/*
284 	 * If inverse mode was selected, invert all the colours
285 	 * rather than the register number.  The register number
286 	 * is what you poke into the framebuffer to produce the
287 	 * colour you requested.
288 	 */
289 	if (fbi->cmap_inverse) {
290 		red   = 0xffff - red;
291 		green = 0xffff - green;
292 		blue  = 0xffff - blue;
293 	}
294 
295 	/*
296 	 * If greyscale is true, then we convert the RGB value
297 	 * to greyscale no mater what visual we are using.
298 	 */
299 	if (info->var.grayscale)
300 		red = green = blue = (19595 * red + 38470 * green +
301 					7471 * blue) >> 16;
302 
303 	switch (info->fix.visual) {
304 	case FB_VISUAL_TRUECOLOR:
305 		/*
306 		 * 12 or 16-bit True Colour.  We encode the RGB value
307 		 * according to the RGB bitfield information.
308 		 */
309 		if (regno < 16) {
310 			u32 *pal = info->pseudo_palette;
311 
312 			val  = chan_to_field(red, &info->var.red);
313 			val |= chan_to_field(green, &info->var.green);
314 			val |= chan_to_field(blue, &info->var.blue);
315 
316 			pal[regno] = val;
317 			ret = 0;
318 		}
319 		break;
320 
321 	case FB_VISUAL_STATIC_PSEUDOCOLOR:
322 	case FB_VISUAL_PSEUDOCOLOR:
323 		ret = imxfb_setpalettereg(regno, red, green, blue, trans, info);
324 		break;
325 	}
326 
327 	return ret;
328 }
329 
330 static const struct imx_fb_videomode *imxfb_find_mode(struct imxfb_info *fbi)
331 {
332 	struct imx_fb_videomode *m;
333 	int i;
334 
335 	if (!fb_mode)
336 		return &fbi->mode[0];
337 
338 	for (i = 0, m = &fbi->mode[0]; i < fbi->num_modes; i++, m++) {
339 		if (!strcmp(m->mode.name, fb_mode))
340 			return m;
341 	}
342 	return NULL;
343 }
344 
345 /*
346  *  imxfb_check_var():
347  *    Round up in the following order: bits_per_pixel, xres,
348  *    yres, xres_virtual, yres_virtual, xoffset, yoffset, grayscale,
349  *    bitfields, horizontal timing, vertical timing.
350  */
351 static int imxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
352 {
353 	struct imxfb_info *fbi = info->par;
354 	struct imxfb_rgb *rgb;
355 	const struct imx_fb_videomode *imxfb_mode;
356 	unsigned long lcd_clk;
357 	unsigned long long tmp;
358 	u32 pcr = 0;
359 
360 	if (var->xres < MIN_XRES)
361 		var->xres = MIN_XRES;
362 	if (var->yres < MIN_YRES)
363 		var->yres = MIN_YRES;
364 
365 	imxfb_mode = imxfb_find_mode(fbi);
366 	if (!imxfb_mode)
367 		return -EINVAL;
368 
369 	var->xres		= imxfb_mode->mode.xres;
370 	var->yres		= imxfb_mode->mode.yres;
371 	var->bits_per_pixel	= imxfb_mode->bpp;
372 	var->pixclock		= imxfb_mode->mode.pixclock;
373 	var->hsync_len		= imxfb_mode->mode.hsync_len;
374 	var->left_margin	= imxfb_mode->mode.left_margin;
375 	var->right_margin	= imxfb_mode->mode.right_margin;
376 	var->vsync_len		= imxfb_mode->mode.vsync_len;
377 	var->upper_margin	= imxfb_mode->mode.upper_margin;
378 	var->lower_margin	= imxfb_mode->mode.lower_margin;
379 	var->sync		= imxfb_mode->mode.sync;
380 	var->xres_virtual	= max(var->xres_virtual, var->xres);
381 	var->yres_virtual	= max(var->yres_virtual, var->yres);
382 
383 	pr_debug("var->bits_per_pixel=%d\n", var->bits_per_pixel);
384 
385 	lcd_clk = clk_get_rate(fbi->clk_per);
386 
387 	tmp = var->pixclock * (unsigned long long)lcd_clk;
388 
389 	do_div(tmp, 1000000);
390 
391 	if (do_div(tmp, 1000000) > 500000)
392 		tmp++;
393 
394 	pcr = (unsigned int)tmp;
395 
396 	if (--pcr > 0x3F) {
397 		pcr = 0x3F;
398 		printk(KERN_WARNING "Must limit pixel clock to %luHz\n",
399 				lcd_clk / pcr);
400 	}
401 
402 	switch (var->bits_per_pixel) {
403 	case 32:
404 		pcr |= PCR_BPIX_18;
405 		rgb = &def_rgb_18;
406 		break;
407 	case 16:
408 	default:
409 		if (is_imx1_fb(fbi))
410 			pcr |= PCR_BPIX_12;
411 		else
412 			pcr |= PCR_BPIX_16;
413 
414 		if (imxfb_mode->pcr & PCR_TFT)
415 			rgb = &def_rgb_16_tft;
416 		else
417 			rgb = &def_rgb_16_stn;
418 		break;
419 	case 8:
420 		pcr |= PCR_BPIX_8;
421 		rgb = &def_rgb_8;
422 		break;
423 	}
424 
425 	/* add sync polarities */
426 	pcr |= imxfb_mode->pcr & ~(0x3f | (7 << 25));
427 
428 	fbi->pcr = pcr;
429 	/*
430 	 * The LCDC AUS Mode Control Register does not exist on imx1.
431 	 */
432 	if (!is_imx1_fb(fbi) && imxfb_mode->aus_mode)
433 		fbi->lauscr = LAUSCR_AUS_MODE;
434 
435 	/*
436 	 * Copy the RGB parameters for this display
437 	 * from the machine specific parameters.
438 	 */
439 	var->red    = rgb->red;
440 	var->green  = rgb->green;
441 	var->blue   = rgb->blue;
442 	var->transp = rgb->transp;
443 
444 	pr_debug("RGBT length = %d:%d:%d:%d\n",
445 		var->red.length, var->green.length, var->blue.length,
446 		var->transp.length);
447 
448 	pr_debug("RGBT offset = %d:%d:%d:%d\n",
449 		var->red.offset, var->green.offset, var->blue.offset,
450 		var->transp.offset);
451 
452 	return 0;
453 }
454 
455 /*
456  * imxfb_set_par():
457  *	Set the user defined part of the display for the specified console
458  */
459 static int imxfb_set_par(struct fb_info *info)
460 {
461 	struct imxfb_info *fbi = info->par;
462 	struct fb_var_screeninfo *var = &info->var;
463 
464 	if (var->bits_per_pixel == 16 || var->bits_per_pixel == 32)
465 		info->fix.visual = FB_VISUAL_TRUECOLOR;
466 	else if (!fbi->cmap_static)
467 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
468 	else {
469 		/*
470 		 * Some people have weird ideas about wanting static
471 		 * pseudocolor maps.  I suspect their user space
472 		 * applications are broken.
473 		 */
474 		info->fix.visual = FB_VISUAL_STATIC_PSEUDOCOLOR;
475 	}
476 
477 	info->fix.line_length = var->xres_virtual * var->bits_per_pixel / 8;
478 	fbi->palette_size = var->bits_per_pixel == 8 ? 256 : 16;
479 
480 	imxfb_activate_var(var, info);
481 
482 	return 0;
483 }
484 
485 static int imxfb_enable_controller(struct imxfb_info *fbi)
486 {
487 	int ret;
488 
489 	if (fbi->enabled)
490 		return 0;
491 
492 	pr_debug("Enabling LCD controller\n");
493 
494 	writel(fbi->map_dma, fbi->regs + LCDC_SSA);
495 
496 	/* panning offset 0 (0 pixel offset)        */
497 	writel(0x00000000, fbi->regs + LCDC_POS);
498 
499 	/* disable hardware cursor */
500 	writel(readl(fbi->regs + LCDC_CPOS) & ~(CPOS_CC0 | CPOS_CC1),
501 		fbi->regs + LCDC_CPOS);
502 
503 	/*
504 	 * RMCR_LCDC_EN_MX1 is present on i.MX1 only, but doesn't hurt
505 	 * on other SoCs
506 	 */
507 	writel(RMCR_LCDC_EN_MX1, fbi->regs + LCDC_RMCR);
508 
509 	ret = clk_prepare_enable(fbi->clk_ipg);
510 	if (ret)
511 		goto err_enable_ipg;
512 
513 	ret = clk_prepare_enable(fbi->clk_ahb);
514 	if (ret)
515 		goto err_enable_ahb;
516 
517 	ret = clk_prepare_enable(fbi->clk_per);
518 	if (ret)
519 		goto err_enable_per;
520 
521 	fbi->enabled = true;
522 	return 0;
523 
524 err_enable_per:
525 	clk_disable_unprepare(fbi->clk_ahb);
526 err_enable_ahb:
527 	clk_disable_unprepare(fbi->clk_ipg);
528 err_enable_ipg:
529 	writel(0, fbi->regs + LCDC_RMCR);
530 
531 	return ret;
532 }
533 
534 static void imxfb_disable_controller(struct imxfb_info *fbi)
535 {
536 	if (!fbi->enabled)
537 		return;
538 
539 	pr_debug("Disabling LCD controller\n");
540 
541 	clk_disable_unprepare(fbi->clk_per);
542 	clk_disable_unprepare(fbi->clk_ahb);
543 	clk_disable_unprepare(fbi->clk_ipg);
544 	fbi->enabled = false;
545 
546 	writel(0, fbi->regs + LCDC_RMCR);
547 }
548 
549 static int imxfb_blank(int blank, struct fb_info *info)
550 {
551 	struct imxfb_info *fbi = info->par;
552 
553 	pr_debug("imxfb_blank: blank=%d\n", blank);
554 
555 	switch (blank) {
556 	case FB_BLANK_POWERDOWN:
557 	case FB_BLANK_VSYNC_SUSPEND:
558 	case FB_BLANK_HSYNC_SUSPEND:
559 	case FB_BLANK_NORMAL:
560 		imxfb_disable_controller(fbi);
561 		break;
562 
563 	case FB_BLANK_UNBLANK:
564 		return imxfb_enable_controller(fbi);
565 	}
566 	return 0;
567 }
568 
569 static struct fb_ops imxfb_ops = {
570 	.owner		= THIS_MODULE,
571 	.fb_check_var	= imxfb_check_var,
572 	.fb_set_par	= imxfb_set_par,
573 	.fb_setcolreg	= imxfb_setcolreg,
574 	.fb_fillrect	= cfb_fillrect,
575 	.fb_copyarea	= cfb_copyarea,
576 	.fb_imageblit	= cfb_imageblit,
577 	.fb_blank	= imxfb_blank,
578 };
579 
580 /*
581  * imxfb_activate_var():
582  *	Configures LCD Controller based on entries in var parameter.  Settings are
583  *	only written to the controller if changes were made.
584  */
585 static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *info)
586 {
587 	struct imxfb_info *fbi = info->par;
588 	u32 ymax_mask = is_imx1_fb(fbi) ? YMAX_MASK_IMX1 : YMAX_MASK_IMX21;
589 
590 	pr_debug("var: xres=%d hslen=%d lm=%d rm=%d\n",
591 		var->xres, var->hsync_len,
592 		var->left_margin, var->right_margin);
593 	pr_debug("var: yres=%d vslen=%d um=%d bm=%d\n",
594 		var->yres, var->vsync_len,
595 		var->upper_margin, var->lower_margin);
596 
597 #if DEBUG_VAR
598 	if (var->xres < 16        || var->xres > 1024)
599 		printk(KERN_ERR "%s: invalid xres %d\n",
600 			info->fix.id, var->xres);
601 	if (var->hsync_len < 1    || var->hsync_len > 64)
602 		printk(KERN_ERR "%s: invalid hsync_len %d\n",
603 			info->fix.id, var->hsync_len);
604 	if (var->left_margin > 255)
605 		printk(KERN_ERR "%s: invalid left_margin %d\n",
606 			info->fix.id, var->left_margin);
607 	if (var->right_margin > 255)
608 		printk(KERN_ERR "%s: invalid right_margin %d\n",
609 			info->fix.id, var->right_margin);
610 	if (var->yres < 1 || var->yres > ymax_mask)
611 		printk(KERN_ERR "%s: invalid yres %d\n",
612 			info->fix.id, var->yres);
613 	if (var->vsync_len > 100)
614 		printk(KERN_ERR "%s: invalid vsync_len %d\n",
615 			info->fix.id, var->vsync_len);
616 	if (var->upper_margin > 63)
617 		printk(KERN_ERR "%s: invalid upper_margin %d\n",
618 			info->fix.id, var->upper_margin);
619 	if (var->lower_margin > 255)
620 		printk(KERN_ERR "%s: invalid lower_margin %d\n",
621 			info->fix.id, var->lower_margin);
622 #endif
623 
624 	/* physical screen start address	    */
625 	writel(VPW_VPW(var->xres * var->bits_per_pixel / 8 / 4),
626 		fbi->regs + LCDC_VPW);
627 
628 	writel(HCR_H_WIDTH(var->hsync_len - 1) |
629 		HCR_H_WAIT_1(var->right_margin - 1) |
630 		HCR_H_WAIT_2(var->left_margin - 3),
631 		fbi->regs + LCDC_HCR);
632 
633 	writel(VCR_V_WIDTH(var->vsync_len) |
634 		VCR_V_WAIT_1(var->lower_margin) |
635 		VCR_V_WAIT_2(var->upper_margin),
636 		fbi->regs + LCDC_VCR);
637 
638 	writel(SIZE_XMAX(var->xres) | (var->yres & ymax_mask),
639 			fbi->regs + LCDC_SIZE);
640 
641 	writel(fbi->pcr, fbi->regs + LCDC_PCR);
642 	if (fbi->pwmr)
643 		writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
644 	writel(fbi->lscr1, fbi->regs + LCDC_LSCR1);
645 
646 	/* dmacr = 0 is no valid value, as we need DMA control marks. */
647 	if (fbi->dmacr)
648 		writel(fbi->dmacr, fbi->regs + LCDC_DMACR);
649 
650 	if (fbi->lauscr)
651 		writel(fbi->lauscr, fbi->regs + LCDC_LAUSCR);
652 
653 	return 0;
654 }
655 
656 static int imxfb_init_fbinfo(struct platform_device *pdev)
657 {
658 	struct imx_fb_platform_data *pdata = dev_get_platdata(&pdev->dev);
659 	struct fb_info *info = dev_get_drvdata(&pdev->dev);
660 	struct imxfb_info *fbi = info->par;
661 	struct device_node *np;
662 
663 	pr_debug("%s\n",__func__);
664 
665 	info->pseudo_palette = kmalloc_array(16, sizeof(u32), GFP_KERNEL);
666 	if (!info->pseudo_palette)
667 		return -ENOMEM;
668 
669 	memset(fbi, 0, sizeof(struct imxfb_info));
670 
671 	fbi->devtype = pdev->id_entry->driver_data;
672 
673 	strlcpy(info->fix.id, IMX_NAME, sizeof(info->fix.id));
674 
675 	info->fix.type			= FB_TYPE_PACKED_PIXELS;
676 	info->fix.type_aux		= 0;
677 	info->fix.xpanstep		= 0;
678 	info->fix.ypanstep		= 0;
679 	info->fix.ywrapstep		= 0;
680 	info->fix.accel			= FB_ACCEL_NONE;
681 
682 	info->var.nonstd		= 0;
683 	info->var.activate		= FB_ACTIVATE_NOW;
684 	info->var.height		= -1;
685 	info->var.width	= -1;
686 	info->var.accel_flags		= 0;
687 	info->var.vmode			= FB_VMODE_NONINTERLACED;
688 
689 	info->fbops			= &imxfb_ops;
690 	info->flags			= FBINFO_FLAG_DEFAULT |
691 					  FBINFO_READS_FAST;
692 	if (pdata) {
693 		fbi->lscr1			= pdata->lscr1;
694 		fbi->dmacr			= pdata->dmacr;
695 		fbi->pwmr			= pdata->pwmr;
696 	} else {
697 		np = pdev->dev.of_node;
698 		info->var.grayscale = of_property_read_bool(np,
699 						"cmap-greyscale");
700 		fbi->cmap_inverse = of_property_read_bool(np, "cmap-inverse");
701 		fbi->cmap_static = of_property_read_bool(np, "cmap-static");
702 
703 		fbi->lscr1 = IMXFB_LSCR1_DEFAULT;
704 
705 		of_property_read_u32(np, "fsl,lpccr", &fbi->pwmr);
706 
707 		of_property_read_u32(np, "fsl,lscr1", &fbi->lscr1);
708 
709 		of_property_read_u32(np, "fsl,dmacr", &fbi->dmacr);
710 	}
711 
712 	return 0;
713 }
714 
715 static int imxfb_of_read_mode(struct device *dev, struct device_node *np,
716 		struct imx_fb_videomode *imxfb_mode)
717 {
718 	int ret;
719 	struct fb_videomode *of_mode = &imxfb_mode->mode;
720 	u32 bpp;
721 	u32 pcr;
722 
723 	ret = of_property_read_string(np, "model", &of_mode->name);
724 	if (ret)
725 		of_mode->name = NULL;
726 
727 	ret = of_get_fb_videomode(np, of_mode, OF_USE_NATIVE_MODE);
728 	if (ret) {
729 		dev_err(dev, "Failed to get videomode from DT\n");
730 		return ret;
731 	}
732 
733 	ret = of_property_read_u32(np, "bits-per-pixel", &bpp);
734 	ret |= of_property_read_u32(np, "fsl,pcr", &pcr);
735 
736 	if (ret) {
737 		dev_err(dev, "Failed to read bpp and pcr from DT\n");
738 		return -EINVAL;
739 	}
740 
741 	if (bpp < 1 || bpp > 255) {
742 		dev_err(dev, "Bits per pixel have to be between 1 and 255\n");
743 		return -EINVAL;
744 	}
745 
746 	imxfb_mode->bpp = bpp;
747 	imxfb_mode->pcr = pcr;
748 
749 	/*
750 	 * fsl,aus-mode is optional
751 	 */
752 	imxfb_mode->aus_mode = of_property_read_bool(np, "fsl,aus-mode");
753 
754 	return 0;
755 }
756 
757 static int imxfb_lcd_check_fb(struct lcd_device *lcddev, struct fb_info *fi)
758 {
759 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
760 
761 	if (!fi || fi->par == fbi)
762 		return 1;
763 
764 	return 0;
765 }
766 
767 static int imxfb_lcd_get_contrast(struct lcd_device *lcddev)
768 {
769 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
770 
771 	return fbi->pwmr & 0xff;
772 }
773 
774 static int imxfb_lcd_set_contrast(struct lcd_device *lcddev, int contrast)
775 {
776 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
777 
778 	if (fbi->pwmr && fbi->enabled) {
779 		if (contrast > 255)
780 			contrast = 255;
781 		else if (contrast < 0)
782 			contrast = 0;
783 
784 		fbi->pwmr &= ~0xff;
785 		fbi->pwmr |= contrast;
786 
787 		writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
788 	}
789 
790 	return 0;
791 }
792 
793 static int imxfb_lcd_get_power(struct lcd_device *lcddev)
794 {
795 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
796 
797 	if (!IS_ERR(fbi->lcd_pwr) &&
798 	    !regulator_is_enabled(fbi->lcd_pwr))
799 		return FB_BLANK_POWERDOWN;
800 
801 	return FB_BLANK_UNBLANK;
802 }
803 
804 static int imxfb_lcd_set_power(struct lcd_device *lcddev, int power)
805 {
806 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
807 
808 	if (!IS_ERR(fbi->lcd_pwr)) {
809 		if (power == FB_BLANK_UNBLANK)
810 			return regulator_enable(fbi->lcd_pwr);
811 		else
812 			return regulator_disable(fbi->lcd_pwr);
813 	}
814 
815 	return 0;
816 }
817 
818 static struct lcd_ops imxfb_lcd_ops = {
819 	.check_fb	= imxfb_lcd_check_fb,
820 	.get_contrast	= imxfb_lcd_get_contrast,
821 	.set_contrast	= imxfb_lcd_set_contrast,
822 	.get_power	= imxfb_lcd_get_power,
823 	.set_power	= imxfb_lcd_set_power,
824 };
825 
826 static int imxfb_setup(void)
827 {
828 	char *opt, *options = NULL;
829 
830 	if (fb_get_options("imxfb", &options))
831 		return -ENODEV;
832 
833 	if (!options || !*options)
834 		return 0;
835 
836 	while ((opt = strsep(&options, ",")) != NULL) {
837 		if (!*opt)
838 			continue;
839 		else
840 			fb_mode = opt;
841 	}
842 
843 	return 0;
844 }
845 
846 static int imxfb_probe(struct platform_device *pdev)
847 {
848 	struct imxfb_info *fbi;
849 	struct lcd_device *lcd;
850 	struct fb_info *info;
851 	struct imx_fb_platform_data *pdata;
852 	struct resource *res;
853 	struct imx_fb_videomode *m;
854 	const struct of_device_id *of_id;
855 	int ret, i;
856 	int bytes_per_pixel;
857 
858 	dev_info(&pdev->dev, "i.MX Framebuffer driver\n");
859 
860 	ret = imxfb_setup();
861 	if (ret < 0)
862 		return ret;
863 
864 	of_id = of_match_device(imxfb_of_dev_id, &pdev->dev);
865 	if (of_id)
866 		pdev->id_entry = of_id->data;
867 
868 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
869 	if (!res)
870 		return -ENODEV;
871 
872 	pdata = dev_get_platdata(&pdev->dev);
873 
874 	info = framebuffer_alloc(sizeof(struct imxfb_info), &pdev->dev);
875 	if (!info)
876 		return -ENOMEM;
877 
878 	fbi = info->par;
879 
880 	platform_set_drvdata(pdev, info);
881 
882 	ret = imxfb_init_fbinfo(pdev);
883 	if (ret < 0)
884 		goto failed_init;
885 
886 	if (pdata) {
887 		if (!fb_mode)
888 			fb_mode = pdata->mode[0].mode.name;
889 
890 		fbi->mode = pdata->mode;
891 		fbi->num_modes = pdata->num_modes;
892 	} else {
893 		struct device_node *display_np;
894 		fb_mode = NULL;
895 
896 		display_np = of_parse_phandle(pdev->dev.of_node, "display", 0);
897 		if (!display_np) {
898 			dev_err(&pdev->dev, "No display defined in devicetree\n");
899 			ret = -EINVAL;
900 			goto failed_of_parse;
901 		}
902 
903 		/*
904 		 * imxfb does not support more modes, we choose only the native
905 		 * mode.
906 		 */
907 		fbi->num_modes = 1;
908 
909 		fbi->mode = devm_kzalloc(&pdev->dev,
910 				sizeof(struct imx_fb_videomode), GFP_KERNEL);
911 		if (!fbi->mode) {
912 			ret = -ENOMEM;
913 			goto failed_of_parse;
914 		}
915 
916 		ret = imxfb_of_read_mode(&pdev->dev, display_np, fbi->mode);
917 		if (ret)
918 			goto failed_of_parse;
919 	}
920 
921 	/* Calculate maximum bytes used per pixel. In most cases this should
922 	 * be the same as m->bpp/8 */
923 	m = &fbi->mode[0];
924 	bytes_per_pixel = (m->bpp + 7) / 8;
925 	for (i = 0; i < fbi->num_modes; i++, m++)
926 		info->fix.smem_len = max_t(size_t, info->fix.smem_len,
927 				m->mode.xres * m->mode.yres * bytes_per_pixel);
928 
929 	res = request_mem_region(res->start, resource_size(res),
930 				DRIVER_NAME);
931 	if (!res) {
932 		ret = -EBUSY;
933 		goto failed_req;
934 	}
935 
936 	fbi->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
937 	if (IS_ERR(fbi->clk_ipg)) {
938 		ret = PTR_ERR(fbi->clk_ipg);
939 		goto failed_getclock;
940 	}
941 
942 	/*
943 	 * The LCDC controller does not have an enable bit. The
944 	 * controller starts directly when the clocks are enabled.
945 	 * If the clocks are enabled when the controller is not yet
946 	 * programmed with proper register values (enabled at the
947 	 * bootloader, for example) then it just goes into some undefined
948 	 * state.
949 	 * To avoid this issue, let's enable and disable LCDC IPG clock
950 	 * so that we force some kind of 'reset' to the LCDC block.
951 	 */
952 	ret = clk_prepare_enable(fbi->clk_ipg);
953 	if (ret)
954 		goto failed_getclock;
955 	clk_disable_unprepare(fbi->clk_ipg);
956 
957 	fbi->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
958 	if (IS_ERR(fbi->clk_ahb)) {
959 		ret = PTR_ERR(fbi->clk_ahb);
960 		goto failed_getclock;
961 	}
962 
963 	fbi->clk_per = devm_clk_get(&pdev->dev, "per");
964 	if (IS_ERR(fbi->clk_per)) {
965 		ret = PTR_ERR(fbi->clk_per);
966 		goto failed_getclock;
967 	}
968 
969 	fbi->regs = ioremap(res->start, resource_size(res));
970 	if (fbi->regs == NULL) {
971 		dev_err(&pdev->dev, "Cannot map frame buffer registers\n");
972 		ret = -ENOMEM;
973 		goto failed_ioremap;
974 	}
975 
976 	fbi->map_size = PAGE_ALIGN(info->fix.smem_len);
977 	info->screen_base = dma_alloc_wc(&pdev->dev, fbi->map_size,
978 					 &fbi->map_dma, GFP_KERNEL);
979 
980 	if (!info->screen_base) {
981 		dev_err(&pdev->dev, "Failed to allocate video RAM: %d\n", ret);
982 		ret = -ENOMEM;
983 		goto failed_map;
984 	}
985 
986 	info->fix.smem_start = fbi->map_dma;
987 
988 	if (pdata && pdata->init) {
989 		ret = pdata->init(fbi->pdev);
990 		if (ret)
991 			goto failed_platform_init;
992 	}
993 
994 
995 	INIT_LIST_HEAD(&info->modelist);
996 	for (i = 0; i < fbi->num_modes; i++)
997 		fb_add_videomode(&fbi->mode[i].mode, &info->modelist);
998 
999 	/*
1000 	 * This makes sure that our colour bitfield
1001 	 * descriptors are correctly initialised.
1002 	 */
1003 	imxfb_check_var(&info->var, info);
1004 
1005 	/*
1006 	 * For modes > 8bpp, the color map is bypassed.
1007 	 * Therefore, 256 entries are enough.
1008 	 */
1009 	ret = fb_alloc_cmap(&info->cmap, 256, 0);
1010 	if (ret < 0)
1011 		goto failed_cmap;
1012 
1013 	imxfb_set_par(info);
1014 	ret = register_framebuffer(info);
1015 	if (ret < 0) {
1016 		dev_err(&pdev->dev, "failed to register framebuffer\n");
1017 		goto failed_register;
1018 	}
1019 
1020 	fbi->lcd_pwr = devm_regulator_get(&pdev->dev, "lcd");
1021 	if (IS_ERR(fbi->lcd_pwr) && (PTR_ERR(fbi->lcd_pwr) == -EPROBE_DEFER)) {
1022 		ret = -EPROBE_DEFER;
1023 		goto failed_lcd;
1024 	}
1025 
1026 	lcd = devm_lcd_device_register(&pdev->dev, "imxfb-lcd", &pdev->dev, fbi,
1027 				       &imxfb_lcd_ops);
1028 	if (IS_ERR(lcd)) {
1029 		ret = PTR_ERR(lcd);
1030 		goto failed_lcd;
1031 	}
1032 
1033 	lcd->props.max_contrast = 0xff;
1034 
1035 	imxfb_enable_controller(fbi);
1036 	fbi->pdev = pdev;
1037 
1038 	return 0;
1039 
1040 failed_lcd:
1041 	unregister_framebuffer(info);
1042 
1043 failed_register:
1044 	fb_dealloc_cmap(&info->cmap);
1045 failed_cmap:
1046 	if (pdata && pdata->exit)
1047 		pdata->exit(fbi->pdev);
1048 failed_platform_init:
1049 	dma_free_wc(&pdev->dev, fbi->map_size, info->screen_base,
1050 		    fbi->map_dma);
1051 failed_map:
1052 	iounmap(fbi->regs);
1053 failed_ioremap:
1054 failed_getclock:
1055 	release_mem_region(res->start, resource_size(res));
1056 failed_req:
1057 failed_of_parse:
1058 	kfree(info->pseudo_palette);
1059 failed_init:
1060 	framebuffer_release(info);
1061 	return ret;
1062 }
1063 
1064 static int imxfb_remove(struct platform_device *pdev)
1065 {
1066 	struct imx_fb_platform_data *pdata;
1067 	struct fb_info *info = platform_get_drvdata(pdev);
1068 	struct imxfb_info *fbi = info->par;
1069 	struct resource *res;
1070 
1071 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1072 
1073 	imxfb_disable_controller(fbi);
1074 
1075 	unregister_framebuffer(info);
1076 	fb_dealloc_cmap(&info->cmap);
1077 	pdata = dev_get_platdata(&pdev->dev);
1078 	if (pdata && pdata->exit)
1079 		pdata->exit(fbi->pdev);
1080 	dma_free_wc(&pdev->dev, fbi->map_size, info->screen_base,
1081 		    fbi->map_dma);
1082 	iounmap(fbi->regs);
1083 	release_mem_region(res->start, resource_size(res));
1084 	kfree(info->pseudo_palette);
1085 	framebuffer_release(info);
1086 
1087 	return 0;
1088 }
1089 
1090 static int __maybe_unused imxfb_suspend(struct device *dev)
1091 {
1092 	struct fb_info *info = dev_get_drvdata(dev);
1093 	struct imxfb_info *fbi = info->par;
1094 
1095 	imxfb_disable_controller(fbi);
1096 
1097 	return 0;
1098 }
1099 
1100 static int __maybe_unused imxfb_resume(struct device *dev)
1101 {
1102 	struct fb_info *info = dev_get_drvdata(dev);
1103 	struct imxfb_info *fbi = info->par;
1104 
1105 	imxfb_enable_controller(fbi);
1106 
1107 	return 0;
1108 }
1109 
1110 static SIMPLE_DEV_PM_OPS(imxfb_pm_ops, imxfb_suspend, imxfb_resume);
1111 
1112 static struct platform_driver imxfb_driver = {
1113 	.driver		= {
1114 		.name	= DRIVER_NAME,
1115 		.of_match_table = imxfb_of_dev_id,
1116 		.pm	= &imxfb_pm_ops,
1117 	},
1118 	.probe		= imxfb_probe,
1119 	.remove		= imxfb_remove,
1120 	.id_table	= imxfb_devtype,
1121 };
1122 module_platform_driver(imxfb_driver);
1123 
1124 MODULE_DESCRIPTION("Freescale i.MX framebuffer driver");
1125 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1126 MODULE_LICENSE("GPL");
1127