xref: /openbmc/linux/drivers/video/fbdev/imxfb.c (revision 2596e07a)
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 /* Used fb-mode. Can be set on kernel command line, therefore file-static. */
121 static const char *fb_mode;
122 
123 /*
124  * These are the bitfields for each
125  * display depth that we support.
126  */
127 struct imxfb_rgb {
128 	struct fb_bitfield	red;
129 	struct fb_bitfield	green;
130 	struct fb_bitfield	blue;
131 	struct fb_bitfield	transp;
132 };
133 
134 enum imxfb_type {
135 	IMX1_FB,
136 	IMX21_FB,
137 };
138 
139 struct imxfb_info {
140 	struct platform_device  *pdev;
141 	void __iomem		*regs;
142 	struct clk		*clk_ipg;
143 	struct clk		*clk_ahb;
144 	struct clk		*clk_per;
145 	enum imxfb_type		devtype;
146 	bool			enabled;
147 
148 	/*
149 	 * These are the addresses we mapped
150 	 * the framebuffer memory region to.
151 	 */
152 	dma_addr_t		map_dma;
153 	u_int			map_size;
154 
155 	u_int			palette_size;
156 
157 	dma_addr_t		dbar1;
158 	dma_addr_t		dbar2;
159 
160 	u_int			pcr;
161 	u_int			pwmr;
162 	u_int			lscr1;
163 	u_int			dmacr;
164 	bool			cmap_inverse;
165 	bool			cmap_static;
166 
167 	struct imx_fb_videomode *mode;
168 	int			num_modes;
169 
170 	struct regulator	*lcd_pwr;
171 };
172 
173 static const struct platform_device_id imxfb_devtype[] = {
174 	{
175 		.name = "imx1-fb",
176 		.driver_data = IMX1_FB,
177 	}, {
178 		.name = "imx21-fb",
179 		.driver_data = IMX21_FB,
180 	}, {
181 		/* sentinel */
182 	}
183 };
184 MODULE_DEVICE_TABLE(platform, imxfb_devtype);
185 
186 static const struct of_device_id imxfb_of_dev_id[] = {
187 	{
188 		.compatible = "fsl,imx1-fb",
189 		.data = &imxfb_devtype[IMX1_FB],
190 	}, {
191 		.compatible = "fsl,imx21-fb",
192 		.data = &imxfb_devtype[IMX21_FB],
193 	}, {
194 		/* sentinel */
195 	}
196 };
197 MODULE_DEVICE_TABLE(of, imxfb_of_dev_id);
198 
199 static inline int is_imx1_fb(struct imxfb_info *fbi)
200 {
201 	return fbi->devtype == IMX1_FB;
202 }
203 
204 #define IMX_NAME	"IMX"
205 
206 /*
207  * Minimum X and Y resolutions
208  */
209 #define MIN_XRES	64
210 #define MIN_YRES	64
211 
212 /* Actually this really is 18bit support, the lowest 2 bits of each colour
213  * are unused in hardware. We claim to have 24bit support to make software
214  * like X work, which does not support 18bit.
215  */
216 static struct imxfb_rgb def_rgb_18 = {
217 	.red	= {.offset = 16, .length = 8,},
218 	.green	= {.offset = 8, .length = 8,},
219 	.blue	= {.offset = 0, .length = 8,},
220 	.transp = {.offset = 0, .length = 0,},
221 };
222 
223 static struct imxfb_rgb def_rgb_16_tft = {
224 	.red	= {.offset = 11, .length = 5,},
225 	.green	= {.offset = 5, .length = 6,},
226 	.blue	= {.offset = 0, .length = 5,},
227 	.transp = {.offset = 0, .length = 0,},
228 };
229 
230 static struct imxfb_rgb def_rgb_16_stn = {
231 	.red	= {.offset = 8, .length = 4,},
232 	.green	= {.offset = 4, .length = 4,},
233 	.blue	= {.offset = 0, .length = 4,},
234 	.transp = {.offset = 0, .length = 0,},
235 };
236 
237 static struct imxfb_rgb def_rgb_8 = {
238 	.red	= {.offset = 0, .length = 8,},
239 	.green	= {.offset = 0, .length = 8,},
240 	.blue	= {.offset = 0, .length = 8,},
241 	.transp = {.offset = 0, .length = 0,},
242 };
243 
244 static int imxfb_activate_var(struct fb_var_screeninfo *var,
245 		struct fb_info *info);
246 
247 static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
248 {
249 	chan &= 0xffff;
250 	chan >>= 16 - bf->length;
251 	return chan << bf->offset;
252 }
253 
254 static int imxfb_setpalettereg(u_int regno, u_int red, u_int green, u_int blue,
255 		u_int trans, struct fb_info *info)
256 {
257 	struct imxfb_info *fbi = info->par;
258 	u_int val, ret = 1;
259 
260 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
261 	if (regno < fbi->palette_size) {
262 		val = (CNVT_TOHW(red, 4) << 8) |
263 		      (CNVT_TOHW(green,4) << 4) |
264 		      CNVT_TOHW(blue,  4);
265 
266 		writel(val, fbi->regs + 0x800 + (regno << 2));
267 		ret = 0;
268 	}
269 	return ret;
270 }
271 
272 static int imxfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
273 		   u_int trans, struct fb_info *info)
274 {
275 	struct imxfb_info *fbi = info->par;
276 	unsigned int val;
277 	int ret = 1;
278 
279 	/*
280 	 * If inverse mode was selected, invert all the colours
281 	 * rather than the register number.  The register number
282 	 * is what you poke into the framebuffer to produce the
283 	 * colour you requested.
284 	 */
285 	if (fbi->cmap_inverse) {
286 		red   = 0xffff - red;
287 		green = 0xffff - green;
288 		blue  = 0xffff - blue;
289 	}
290 
291 	/*
292 	 * If greyscale is true, then we convert the RGB value
293 	 * to greyscale no mater what visual we are using.
294 	 */
295 	if (info->var.grayscale)
296 		red = green = blue = (19595 * red + 38470 * green +
297 					7471 * blue) >> 16;
298 
299 	switch (info->fix.visual) {
300 	case FB_VISUAL_TRUECOLOR:
301 		/*
302 		 * 12 or 16-bit True Colour.  We encode the RGB value
303 		 * according to the RGB bitfield information.
304 		 */
305 		if (regno < 16) {
306 			u32 *pal = info->pseudo_palette;
307 
308 			val  = chan_to_field(red, &info->var.red);
309 			val |= chan_to_field(green, &info->var.green);
310 			val |= chan_to_field(blue, &info->var.blue);
311 
312 			pal[regno] = val;
313 			ret = 0;
314 		}
315 		break;
316 
317 	case FB_VISUAL_STATIC_PSEUDOCOLOR:
318 	case FB_VISUAL_PSEUDOCOLOR:
319 		ret = imxfb_setpalettereg(regno, red, green, blue, trans, info);
320 		break;
321 	}
322 
323 	return ret;
324 }
325 
326 static const struct imx_fb_videomode *imxfb_find_mode(struct imxfb_info *fbi)
327 {
328 	struct imx_fb_videomode *m;
329 	int i;
330 
331 	if (!fb_mode)
332 		return &fbi->mode[0];
333 
334 	for (i = 0, m = &fbi->mode[0]; i < fbi->num_modes; i++, m++) {
335 		if (!strcmp(m->mode.name, fb_mode))
336 			return m;
337 	}
338 	return NULL;
339 }
340 
341 /*
342  *  imxfb_check_var():
343  *    Round up in the following order: bits_per_pixel, xres,
344  *    yres, xres_virtual, yres_virtual, xoffset, yoffset, grayscale,
345  *    bitfields, horizontal timing, vertical timing.
346  */
347 static int imxfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
348 {
349 	struct imxfb_info *fbi = info->par;
350 	struct imxfb_rgb *rgb;
351 	const struct imx_fb_videomode *imxfb_mode;
352 	unsigned long lcd_clk;
353 	unsigned long long tmp;
354 	u32 pcr = 0;
355 
356 	if (var->xres < MIN_XRES)
357 		var->xres = MIN_XRES;
358 	if (var->yres < MIN_YRES)
359 		var->yres = MIN_YRES;
360 
361 	imxfb_mode = imxfb_find_mode(fbi);
362 	if (!imxfb_mode)
363 		return -EINVAL;
364 
365 	var->xres		= imxfb_mode->mode.xres;
366 	var->yres		= imxfb_mode->mode.yres;
367 	var->bits_per_pixel	= imxfb_mode->bpp;
368 	var->pixclock		= imxfb_mode->mode.pixclock;
369 	var->hsync_len		= imxfb_mode->mode.hsync_len;
370 	var->left_margin	= imxfb_mode->mode.left_margin;
371 	var->right_margin	= imxfb_mode->mode.right_margin;
372 	var->vsync_len		= imxfb_mode->mode.vsync_len;
373 	var->upper_margin	= imxfb_mode->mode.upper_margin;
374 	var->lower_margin	= imxfb_mode->mode.lower_margin;
375 	var->sync		= imxfb_mode->mode.sync;
376 	var->xres_virtual	= max(var->xres_virtual, var->xres);
377 	var->yres_virtual	= max(var->yres_virtual, var->yres);
378 
379 	pr_debug("var->bits_per_pixel=%d\n", var->bits_per_pixel);
380 
381 	lcd_clk = clk_get_rate(fbi->clk_per);
382 
383 	tmp = var->pixclock * (unsigned long long)lcd_clk;
384 
385 	do_div(tmp, 1000000);
386 
387 	if (do_div(tmp, 1000000) > 500000)
388 		tmp++;
389 
390 	pcr = (unsigned int)tmp;
391 
392 	if (--pcr > 0x3F) {
393 		pcr = 0x3F;
394 		printk(KERN_WARNING "Must limit pixel clock to %luHz\n",
395 				lcd_clk / pcr);
396 	}
397 
398 	switch (var->bits_per_pixel) {
399 	case 32:
400 		pcr |= PCR_BPIX_18;
401 		rgb = &def_rgb_18;
402 		break;
403 	case 16:
404 	default:
405 		if (is_imx1_fb(fbi))
406 			pcr |= PCR_BPIX_12;
407 		else
408 			pcr |= PCR_BPIX_16;
409 
410 		if (imxfb_mode->pcr & PCR_TFT)
411 			rgb = &def_rgb_16_tft;
412 		else
413 			rgb = &def_rgb_16_stn;
414 		break;
415 	case 8:
416 		pcr |= PCR_BPIX_8;
417 		rgb = &def_rgb_8;
418 		break;
419 	}
420 
421 	/* add sync polarities */
422 	pcr |= imxfb_mode->pcr & ~(0x3f | (7 << 25));
423 
424 	fbi->pcr = pcr;
425 
426 	/*
427 	 * Copy the RGB parameters for this display
428 	 * from the machine specific parameters.
429 	 */
430 	var->red    = rgb->red;
431 	var->green  = rgb->green;
432 	var->blue   = rgb->blue;
433 	var->transp = rgb->transp;
434 
435 	pr_debug("RGBT length = %d:%d:%d:%d\n",
436 		var->red.length, var->green.length, var->blue.length,
437 		var->transp.length);
438 
439 	pr_debug("RGBT offset = %d:%d:%d:%d\n",
440 		var->red.offset, var->green.offset, var->blue.offset,
441 		var->transp.offset);
442 
443 	return 0;
444 }
445 
446 /*
447  * imxfb_set_par():
448  *	Set the user defined part of the display for the specified console
449  */
450 static int imxfb_set_par(struct fb_info *info)
451 {
452 	struct imxfb_info *fbi = info->par;
453 	struct fb_var_screeninfo *var = &info->var;
454 
455 	if (var->bits_per_pixel == 16 || var->bits_per_pixel == 32)
456 		info->fix.visual = FB_VISUAL_TRUECOLOR;
457 	else if (!fbi->cmap_static)
458 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
459 	else {
460 		/*
461 		 * Some people have weird ideas about wanting static
462 		 * pseudocolor maps.  I suspect their user space
463 		 * applications are broken.
464 		 */
465 		info->fix.visual = FB_VISUAL_STATIC_PSEUDOCOLOR;
466 	}
467 
468 	info->fix.line_length = var->xres_virtual * var->bits_per_pixel / 8;
469 	fbi->palette_size = var->bits_per_pixel == 8 ? 256 : 16;
470 
471 	imxfb_activate_var(var, info);
472 
473 	return 0;
474 }
475 
476 static void imxfb_enable_controller(struct imxfb_info *fbi)
477 {
478 
479 	if (fbi->enabled)
480 		return;
481 
482 	pr_debug("Enabling LCD controller\n");
483 
484 	writel(fbi->map_dma, fbi->regs + LCDC_SSA);
485 
486 	/* panning offset 0 (0 pixel offset)        */
487 	writel(0x00000000, fbi->regs + LCDC_POS);
488 
489 	/* disable hardware cursor */
490 	writel(readl(fbi->regs + LCDC_CPOS) & ~(CPOS_CC0 | CPOS_CC1),
491 		fbi->regs + LCDC_CPOS);
492 
493 	/*
494 	 * RMCR_LCDC_EN_MX1 is present on i.MX1 only, but doesn't hurt
495 	 * on other SoCs
496 	 */
497 	writel(RMCR_LCDC_EN_MX1, fbi->regs + LCDC_RMCR);
498 
499 	clk_prepare_enable(fbi->clk_ipg);
500 	clk_prepare_enable(fbi->clk_ahb);
501 	clk_prepare_enable(fbi->clk_per);
502 	fbi->enabled = true;
503 }
504 
505 static void imxfb_disable_controller(struct imxfb_info *fbi)
506 {
507 	if (!fbi->enabled)
508 		return;
509 
510 	pr_debug("Disabling LCD controller\n");
511 
512 	clk_disable_unprepare(fbi->clk_per);
513 	clk_disable_unprepare(fbi->clk_ipg);
514 	clk_disable_unprepare(fbi->clk_ahb);
515 	fbi->enabled = false;
516 
517 	writel(0, fbi->regs + LCDC_RMCR);
518 }
519 
520 static int imxfb_blank(int blank, struct fb_info *info)
521 {
522 	struct imxfb_info *fbi = info->par;
523 
524 	pr_debug("imxfb_blank: blank=%d\n", blank);
525 
526 	switch (blank) {
527 	case FB_BLANK_POWERDOWN:
528 	case FB_BLANK_VSYNC_SUSPEND:
529 	case FB_BLANK_HSYNC_SUSPEND:
530 	case FB_BLANK_NORMAL:
531 		imxfb_disable_controller(fbi);
532 		break;
533 
534 	case FB_BLANK_UNBLANK:
535 		imxfb_enable_controller(fbi);
536 		break;
537 	}
538 	return 0;
539 }
540 
541 static struct fb_ops imxfb_ops = {
542 	.owner		= THIS_MODULE,
543 	.fb_check_var	= imxfb_check_var,
544 	.fb_set_par	= imxfb_set_par,
545 	.fb_setcolreg	= imxfb_setcolreg,
546 	.fb_fillrect	= cfb_fillrect,
547 	.fb_copyarea	= cfb_copyarea,
548 	.fb_imageblit	= cfb_imageblit,
549 	.fb_blank	= imxfb_blank,
550 };
551 
552 /*
553  * imxfb_activate_var():
554  *	Configures LCD Controller based on entries in var parameter.  Settings are
555  *	only written to the controller if changes were made.
556  */
557 static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *info)
558 {
559 	struct imxfb_info *fbi = info->par;
560 	u32 ymax_mask = is_imx1_fb(fbi) ? YMAX_MASK_IMX1 : YMAX_MASK_IMX21;
561 
562 	pr_debug("var: xres=%d hslen=%d lm=%d rm=%d\n",
563 		var->xres, var->hsync_len,
564 		var->left_margin, var->right_margin);
565 	pr_debug("var: yres=%d vslen=%d um=%d bm=%d\n",
566 		var->yres, var->vsync_len,
567 		var->upper_margin, var->lower_margin);
568 
569 #if DEBUG_VAR
570 	if (var->xres < 16        || var->xres > 1024)
571 		printk(KERN_ERR "%s: invalid xres %d\n",
572 			info->fix.id, var->xres);
573 	if (var->hsync_len < 1    || var->hsync_len > 64)
574 		printk(KERN_ERR "%s: invalid hsync_len %d\n",
575 			info->fix.id, var->hsync_len);
576 	if (var->left_margin > 255)
577 		printk(KERN_ERR "%s: invalid left_margin %d\n",
578 			info->fix.id, var->left_margin);
579 	if (var->right_margin > 255)
580 		printk(KERN_ERR "%s: invalid right_margin %d\n",
581 			info->fix.id, var->right_margin);
582 	if (var->yres < 1 || var->yres > ymax_mask)
583 		printk(KERN_ERR "%s: invalid yres %d\n",
584 			info->fix.id, var->yres);
585 	if (var->vsync_len > 100)
586 		printk(KERN_ERR "%s: invalid vsync_len %d\n",
587 			info->fix.id, var->vsync_len);
588 	if (var->upper_margin > 63)
589 		printk(KERN_ERR "%s: invalid upper_margin %d\n",
590 			info->fix.id, var->upper_margin);
591 	if (var->lower_margin > 255)
592 		printk(KERN_ERR "%s: invalid lower_margin %d\n",
593 			info->fix.id, var->lower_margin);
594 #endif
595 
596 	/* physical screen start address	    */
597 	writel(VPW_VPW(var->xres * var->bits_per_pixel / 8 / 4),
598 		fbi->regs + LCDC_VPW);
599 
600 	writel(HCR_H_WIDTH(var->hsync_len - 1) |
601 		HCR_H_WAIT_1(var->right_margin - 1) |
602 		HCR_H_WAIT_2(var->left_margin - 3),
603 		fbi->regs + LCDC_HCR);
604 
605 	writel(VCR_V_WIDTH(var->vsync_len) |
606 		VCR_V_WAIT_1(var->lower_margin) |
607 		VCR_V_WAIT_2(var->upper_margin),
608 		fbi->regs + LCDC_VCR);
609 
610 	writel(SIZE_XMAX(var->xres) | (var->yres & ymax_mask),
611 			fbi->regs + LCDC_SIZE);
612 
613 	writel(fbi->pcr, fbi->regs + LCDC_PCR);
614 	if (fbi->pwmr)
615 		writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
616 	writel(fbi->lscr1, fbi->regs + LCDC_LSCR1);
617 
618 	/* dmacr = 0 is no valid value, as we need DMA control marks. */
619 	if (fbi->dmacr)
620 		writel(fbi->dmacr, fbi->regs + LCDC_DMACR);
621 
622 	return 0;
623 }
624 
625 static int imxfb_init_fbinfo(struct platform_device *pdev)
626 {
627 	struct imx_fb_platform_data *pdata = dev_get_platdata(&pdev->dev);
628 	struct fb_info *info = dev_get_drvdata(&pdev->dev);
629 	struct imxfb_info *fbi = info->par;
630 	struct device_node *np;
631 
632 	pr_debug("%s\n",__func__);
633 
634 	info->pseudo_palette = kmalloc(sizeof(u32) * 16, GFP_KERNEL);
635 	if (!info->pseudo_palette)
636 		return -ENOMEM;
637 
638 	memset(fbi, 0, sizeof(struct imxfb_info));
639 
640 	fbi->devtype = pdev->id_entry->driver_data;
641 
642 	strlcpy(info->fix.id, IMX_NAME, sizeof(info->fix.id));
643 
644 	info->fix.type			= FB_TYPE_PACKED_PIXELS;
645 	info->fix.type_aux		= 0;
646 	info->fix.xpanstep		= 0;
647 	info->fix.ypanstep		= 0;
648 	info->fix.ywrapstep		= 0;
649 	info->fix.accel			= FB_ACCEL_NONE;
650 
651 	info->var.nonstd		= 0;
652 	info->var.activate		= FB_ACTIVATE_NOW;
653 	info->var.height		= -1;
654 	info->var.width	= -1;
655 	info->var.accel_flags		= 0;
656 	info->var.vmode			= FB_VMODE_NONINTERLACED;
657 
658 	info->fbops			= &imxfb_ops;
659 	info->flags			= FBINFO_FLAG_DEFAULT |
660 					  FBINFO_READS_FAST;
661 	if (pdata) {
662 		fbi->lscr1			= pdata->lscr1;
663 		fbi->dmacr			= pdata->dmacr;
664 		fbi->pwmr			= pdata->pwmr;
665 	} else {
666 		np = pdev->dev.of_node;
667 		info->var.grayscale = of_property_read_bool(np,
668 						"cmap-greyscale");
669 		fbi->cmap_inverse = of_property_read_bool(np, "cmap-inverse");
670 		fbi->cmap_static = of_property_read_bool(np, "cmap-static");
671 
672 		fbi->lscr1 = IMXFB_LSCR1_DEFAULT;
673 
674 		of_property_read_u32(np, "fsl,lpccr", &fbi->pwmr);
675 
676 		of_property_read_u32(np, "fsl,lscr1", &fbi->lscr1);
677 
678 		of_property_read_u32(np, "fsl,dmacr", &fbi->dmacr);
679 	}
680 
681 	return 0;
682 }
683 
684 static int imxfb_of_read_mode(struct device *dev, struct device_node *np,
685 		struct imx_fb_videomode *imxfb_mode)
686 {
687 	int ret;
688 	struct fb_videomode *of_mode = &imxfb_mode->mode;
689 	u32 bpp;
690 	u32 pcr;
691 
692 	ret = of_property_read_string(np, "model", &of_mode->name);
693 	if (ret)
694 		of_mode->name = NULL;
695 
696 	ret = of_get_fb_videomode(np, of_mode, OF_USE_NATIVE_MODE);
697 	if (ret) {
698 		dev_err(dev, "Failed to get videomode from DT\n");
699 		return ret;
700 	}
701 
702 	ret = of_property_read_u32(np, "bits-per-pixel", &bpp);
703 	ret |= of_property_read_u32(np, "fsl,pcr", &pcr);
704 
705 	if (ret) {
706 		dev_err(dev, "Failed to read bpp and pcr from DT\n");
707 		return -EINVAL;
708 	}
709 
710 	if (bpp < 1 || bpp > 255) {
711 		dev_err(dev, "Bits per pixel have to be between 1 and 255\n");
712 		return -EINVAL;
713 	}
714 
715 	imxfb_mode->bpp = bpp;
716 	imxfb_mode->pcr = pcr;
717 
718 	return 0;
719 }
720 
721 static int imxfb_lcd_check_fb(struct lcd_device *lcddev, struct fb_info *fi)
722 {
723 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
724 
725 	if (!fi || fi->par == fbi)
726 		return 1;
727 
728 	return 0;
729 }
730 
731 static int imxfb_lcd_get_contrast(struct lcd_device *lcddev)
732 {
733 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
734 
735 	return fbi->pwmr & 0xff;
736 }
737 
738 static int imxfb_lcd_set_contrast(struct lcd_device *lcddev, int contrast)
739 {
740 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
741 
742 	if (fbi->pwmr && fbi->enabled) {
743 		if (contrast > 255)
744 			contrast = 255;
745 		else if (contrast < 0)
746 			contrast = 0;
747 
748 		fbi->pwmr &= ~0xff;
749 		fbi->pwmr |= contrast;
750 
751 		writel(fbi->pwmr, fbi->regs + LCDC_PWMR);
752 	}
753 
754 	return 0;
755 }
756 
757 static int imxfb_lcd_get_power(struct lcd_device *lcddev)
758 {
759 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
760 
761 	if (!IS_ERR(fbi->lcd_pwr))
762 		return regulator_is_enabled(fbi->lcd_pwr);
763 
764 	return 1;
765 }
766 
767 static int imxfb_lcd_set_power(struct lcd_device *lcddev, int power)
768 {
769 	struct imxfb_info *fbi = dev_get_drvdata(&lcddev->dev);
770 
771 	if (!IS_ERR(fbi->lcd_pwr)) {
772 		if (power)
773 			return regulator_enable(fbi->lcd_pwr);
774 		else
775 			return regulator_disable(fbi->lcd_pwr);
776 	}
777 
778 	return 0;
779 }
780 
781 static struct lcd_ops imxfb_lcd_ops = {
782 	.check_fb	= imxfb_lcd_check_fb,
783 	.get_contrast	= imxfb_lcd_get_contrast,
784 	.set_contrast	= imxfb_lcd_set_contrast,
785 	.get_power	= imxfb_lcd_get_power,
786 	.set_power	= imxfb_lcd_set_power,
787 };
788 
789 static int imxfb_setup(void)
790 {
791 	char *opt, *options = NULL;
792 
793 	if (fb_get_options("imxfb", &options))
794 		return -ENODEV;
795 
796 	if (!options || !*options)
797 		return 0;
798 
799 	while ((opt = strsep(&options, ",")) != NULL) {
800 		if (!*opt)
801 			continue;
802 		else
803 			fb_mode = opt;
804 	}
805 
806 	return 0;
807 }
808 
809 static int imxfb_probe(struct platform_device *pdev)
810 {
811 	struct imxfb_info *fbi;
812 	struct lcd_device *lcd;
813 	struct fb_info *info;
814 	struct imx_fb_platform_data *pdata;
815 	struct resource *res;
816 	struct imx_fb_videomode *m;
817 	const struct of_device_id *of_id;
818 	int ret, i;
819 	int bytes_per_pixel;
820 
821 	dev_info(&pdev->dev, "i.MX Framebuffer driver\n");
822 
823 	ret = imxfb_setup();
824 	if (ret < 0)
825 		return ret;
826 
827 	of_id = of_match_device(imxfb_of_dev_id, &pdev->dev);
828 	if (of_id)
829 		pdev->id_entry = of_id->data;
830 
831 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
832 	if (!res)
833 		return -ENODEV;
834 
835 	pdata = dev_get_platdata(&pdev->dev);
836 
837 	info = framebuffer_alloc(sizeof(struct imxfb_info), &pdev->dev);
838 	if (!info)
839 		return -ENOMEM;
840 
841 	fbi = info->par;
842 
843 	platform_set_drvdata(pdev, info);
844 
845 	ret = imxfb_init_fbinfo(pdev);
846 	if (ret < 0)
847 		goto failed_init;
848 
849 	if (pdata) {
850 		if (!fb_mode)
851 			fb_mode = pdata->mode[0].mode.name;
852 
853 		fbi->mode = pdata->mode;
854 		fbi->num_modes = pdata->num_modes;
855 	} else {
856 		struct device_node *display_np;
857 		fb_mode = NULL;
858 
859 		display_np = of_parse_phandle(pdev->dev.of_node, "display", 0);
860 		if (!display_np) {
861 			dev_err(&pdev->dev, "No display defined in devicetree\n");
862 			ret = -EINVAL;
863 			goto failed_of_parse;
864 		}
865 
866 		/*
867 		 * imxfb does not support more modes, we choose only the native
868 		 * mode.
869 		 */
870 		fbi->num_modes = 1;
871 
872 		fbi->mode = devm_kzalloc(&pdev->dev,
873 				sizeof(struct imx_fb_videomode), GFP_KERNEL);
874 		if (!fbi->mode) {
875 			ret = -ENOMEM;
876 			goto failed_of_parse;
877 		}
878 
879 		ret = imxfb_of_read_mode(&pdev->dev, display_np, fbi->mode);
880 		if (ret)
881 			goto failed_of_parse;
882 	}
883 
884 	/* Calculate maximum bytes used per pixel. In most cases this should
885 	 * be the same as m->bpp/8 */
886 	m = &fbi->mode[0];
887 	bytes_per_pixel = (m->bpp + 7) / 8;
888 	for (i = 0; i < fbi->num_modes; i++, m++)
889 		info->fix.smem_len = max_t(size_t, info->fix.smem_len,
890 				m->mode.xres * m->mode.yres * bytes_per_pixel);
891 
892 	res = request_mem_region(res->start, resource_size(res),
893 				DRIVER_NAME);
894 	if (!res) {
895 		ret = -EBUSY;
896 		goto failed_req;
897 	}
898 
899 	fbi->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
900 	if (IS_ERR(fbi->clk_ipg)) {
901 		ret = PTR_ERR(fbi->clk_ipg);
902 		goto failed_getclock;
903 	}
904 
905 	/*
906 	 * The LCDC controller does not have an enable bit. The
907 	 * controller starts directly when the clocks are enabled.
908 	 * If the clocks are enabled when the controller is not yet
909 	 * programmed with proper register values (enabled at the
910 	 * bootloader, for example) then it just goes into some undefined
911 	 * state.
912 	 * To avoid this issue, let's enable and disable LCDC IPG clock
913 	 * so that we force some kind of 'reset' to the LCDC block.
914 	 */
915 	ret = clk_prepare_enable(fbi->clk_ipg);
916 	if (ret)
917 		goto failed_getclock;
918 	clk_disable_unprepare(fbi->clk_ipg);
919 
920 	fbi->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
921 	if (IS_ERR(fbi->clk_ahb)) {
922 		ret = PTR_ERR(fbi->clk_ahb);
923 		goto failed_getclock;
924 	}
925 
926 	fbi->clk_per = devm_clk_get(&pdev->dev, "per");
927 	if (IS_ERR(fbi->clk_per)) {
928 		ret = PTR_ERR(fbi->clk_per);
929 		goto failed_getclock;
930 	}
931 
932 	fbi->regs = ioremap(res->start, resource_size(res));
933 	if (fbi->regs == NULL) {
934 		dev_err(&pdev->dev, "Cannot map frame buffer registers\n");
935 		ret = -ENOMEM;
936 		goto failed_ioremap;
937 	}
938 
939 	fbi->map_size = PAGE_ALIGN(info->fix.smem_len);
940 	info->screen_base = dma_alloc_writecombine(&pdev->dev, fbi->map_size,
941 						   &fbi->map_dma, GFP_KERNEL);
942 
943 	if (!info->screen_base) {
944 		dev_err(&pdev->dev, "Failed to allocate video RAM: %d\n", ret);
945 		ret = -ENOMEM;
946 		goto failed_map;
947 	}
948 
949 	info->fix.smem_start = fbi->map_dma;
950 
951 	if (pdata && pdata->init) {
952 		ret = pdata->init(fbi->pdev);
953 		if (ret)
954 			goto failed_platform_init;
955 	}
956 
957 
958 	INIT_LIST_HEAD(&info->modelist);
959 	for (i = 0; i < fbi->num_modes; i++)
960 		fb_add_videomode(&fbi->mode[i].mode, &info->modelist);
961 
962 	/*
963 	 * This makes sure that our colour bitfield
964 	 * descriptors are correctly initialised.
965 	 */
966 	imxfb_check_var(&info->var, info);
967 
968 	ret = fb_alloc_cmap(&info->cmap, 1 << info->var.bits_per_pixel, 0);
969 	if (ret < 0)
970 		goto failed_cmap;
971 
972 	imxfb_set_par(info);
973 	ret = register_framebuffer(info);
974 	if (ret < 0) {
975 		dev_err(&pdev->dev, "failed to register framebuffer\n");
976 		goto failed_register;
977 	}
978 
979 	fbi->lcd_pwr = devm_regulator_get(&pdev->dev, "lcd");
980 	if (IS_ERR(fbi->lcd_pwr) && (PTR_ERR(fbi->lcd_pwr) == -EPROBE_DEFER)) {
981 		ret = -EPROBE_DEFER;
982 		goto failed_lcd;
983 	}
984 
985 	lcd = devm_lcd_device_register(&pdev->dev, "imxfb-lcd", &pdev->dev, fbi,
986 				       &imxfb_lcd_ops);
987 	if (IS_ERR(lcd)) {
988 		ret = PTR_ERR(lcd);
989 		goto failed_lcd;
990 	}
991 
992 	lcd->props.max_contrast = 0xff;
993 
994 	imxfb_enable_controller(fbi);
995 	fbi->pdev = pdev;
996 
997 	return 0;
998 
999 failed_lcd:
1000 	unregister_framebuffer(info);
1001 
1002 failed_register:
1003 	fb_dealloc_cmap(&info->cmap);
1004 failed_cmap:
1005 	if (pdata && pdata->exit)
1006 		pdata->exit(fbi->pdev);
1007 failed_platform_init:
1008 	dma_free_writecombine(&pdev->dev, fbi->map_size, info->screen_base,
1009 			      fbi->map_dma);
1010 failed_map:
1011 	iounmap(fbi->regs);
1012 failed_ioremap:
1013 failed_getclock:
1014 	release_mem_region(res->start, resource_size(res));
1015 failed_req:
1016 failed_of_parse:
1017 	kfree(info->pseudo_palette);
1018 failed_init:
1019 	framebuffer_release(info);
1020 	return ret;
1021 }
1022 
1023 static int imxfb_remove(struct platform_device *pdev)
1024 {
1025 	struct imx_fb_platform_data *pdata;
1026 	struct fb_info *info = platform_get_drvdata(pdev);
1027 	struct imxfb_info *fbi = info->par;
1028 	struct resource *res;
1029 
1030 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1031 
1032 	imxfb_disable_controller(fbi);
1033 
1034 	unregister_framebuffer(info);
1035 
1036 	pdata = dev_get_platdata(&pdev->dev);
1037 	if (pdata && pdata->exit)
1038 		pdata->exit(fbi->pdev);
1039 
1040 	fb_dealloc_cmap(&info->cmap);
1041 	kfree(info->pseudo_palette);
1042 	framebuffer_release(info);
1043 
1044 	dma_free_writecombine(&pdev->dev, fbi->map_size, info->screen_base,
1045 			      fbi->map_dma);
1046 
1047 	iounmap(fbi->regs);
1048 	release_mem_region(res->start, resource_size(res));
1049 
1050 	return 0;
1051 }
1052 
1053 static int __maybe_unused imxfb_suspend(struct device *dev)
1054 {
1055 	struct fb_info *info = dev_get_drvdata(dev);
1056 	struct imxfb_info *fbi = info->par;
1057 
1058 	imxfb_disable_controller(fbi);
1059 
1060 	return 0;
1061 }
1062 
1063 static int __maybe_unused imxfb_resume(struct device *dev)
1064 {
1065 	struct fb_info *info = dev_get_drvdata(dev);
1066 	struct imxfb_info *fbi = info->par;
1067 
1068 	imxfb_enable_controller(fbi);
1069 
1070 	return 0;
1071 }
1072 
1073 static SIMPLE_DEV_PM_OPS(imxfb_pm_ops, imxfb_suspend, imxfb_resume);
1074 
1075 static struct platform_driver imxfb_driver = {
1076 	.driver		= {
1077 		.name	= DRIVER_NAME,
1078 		.of_match_table = imxfb_of_dev_id,
1079 		.pm	= &imxfb_pm_ops,
1080 	},
1081 	.probe		= imxfb_probe,
1082 	.remove		= imxfb_remove,
1083 	.id_table	= imxfb_devtype,
1084 };
1085 module_platform_driver(imxfb_driver);
1086 
1087 MODULE_DESCRIPTION("Freescale i.MX framebuffer driver");
1088 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1089 MODULE_LICENSE("GPL");
1090