1	/*
2	* linux/drivers/video/fbmon.c
3	*
4	* Copyright (C) 2002 James Simmons <jsimmons@users.sf.net>
5	*
6	* Credits:
7	*
8	* The EDID Parser is a conglomeration from the following sources:
9	*
10	* 1. SciTech SNAP Graphics Architecture
11	* Copyright (C) 1991-2002 SciTech Software, Inc. All rights reserved.
12	*
13	* 2. XFree86 4.3.0, interpret_edid.c
14	* Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
15	*
16	* 3. John Fremlin <vii@users.sourceforge.net> and
17	* Ani Joshi <ajoshi@unixbox.com>
18	*
19	* Generalized Timing Formula is derived from:
20	*
21	* GTF Spreadsheet by Andy Morrish (1/5/97)
22	* available at https://www.vesa.org
23	*
24	* This file is subject to the terms and conditions of the GNU General Public
25	* License. See the file COPYING in the main directory of this archive
26	* for more details.
27	*
28	*/
29	#include <linux/fb.h>
30	#include <linux/module.h>
31	#include <linux/pci.h>
32	#include <linux/slab.h>
33	#include <video/edid.h>
34	#include <video/of_videomode.h>
35	#include <video/videomode.h>
36	#include "../edid.h"
37
38	/*
39	* EDID parser
40	*/
41
42	#undef DEBUG /* define this for verbose EDID parsing output */
43
44	#ifdef DEBUG
45	#define DPRINTK(fmt, args...) printk(fmt,## args)
46	#else
47	#define DPRINTK(fmt, args...) no_printk(fmt, ##args)
48	#endif
49
50	#define FBMON_FIX_HEADER 1
51	#define FBMON_FIX_INPUT 2
52	#define FBMON_FIX_TIMINGS 3
53
54	#ifdef CONFIG_FB_MODE_HELPERS
55	struct broken_edid {
56	u8 manufacturer[4];
57	u32 model;
58	u32 fix;
59	};
60
61	static const struct broken_edid brokendb[] = {
62	/* DEC FR-PCXAV-YZ */
63	{
64	.manufacturer = "DEC",
65	.model = 0x073a,
66	.fix = FBMON_FIX_HEADER,
67	},
68	/* ViewSonic PF775a */
69	{
70	.manufacturer = "VSC",
71	.model = 0x5a44,
72	.fix = FBMON_FIX_INPUT,
73	},
74	/* Sharp UXGA? */
75	{
76	.manufacturer = "SHP",
77	.model = 0x138e,
78	.fix = FBMON_FIX_TIMINGS,
79	},
80	};
81
82	static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
83	0xff, 0xff, 0xff, 0x00
84	};
85
86	static void copy_string(unsigned char *c, unsigned char *s)
87	{
88	int i;
89	c = c + 5;
90	for (i = 0; (i < 13 && *c != 0x0A); i++)
91	*(s++) = *(c++);
92	*s = 0;
93	while (i-- && (*--s == 0x20)) *s = 0;
94	}
95
96	static int edid_is_serial_block(unsigned char *block)
97	{
98	if ((block[0] == 0x00) && (block[1] == 0x00) &&
99	(block[2] == 0x00) && (block[3] == 0xff) &&
100	(block[4] == 0x00))
101	return 1;
102	else
103	return 0;
104	}
105
106	static int edid_is_ascii_block(unsigned char *block)
107	{
108	if ((block[0] == 0x00) && (block[1] == 0x00) &&
109	(block[2] == 0x00) && (block[3] == 0xfe) &&
110	(block[4] == 0x00))
111	return 1;
112	else
113	return 0;
114	}
115
116	static int edid_is_limits_block(unsigned char *block)
117	{
118	if ((block[0] == 0x00) && (block[1] == 0x00) &&
119	(block[2] == 0x00) && (block[3] == 0xfd) &&
120	(block[4] == 0x00))
121	return 1;
122	else
123	return 0;
124	}
125
126	static int edid_is_monitor_block(unsigned char *block)
127	{
128	if ((block[0] == 0x00) && (block[1] == 0x00) &&
129	(block[2] == 0x00) && (block[3] == 0xfc) &&
130	(block[4] == 0x00))
131	return 1;
132	else
133	return 0;
134	}
135
136	static int edid_is_timing_block(unsigned char *block)
137	{
138	if ((block[0] != 0x00) || (block[1] != 0x00) ||
139	(block[2] != 0x00) || (block[4] != 0x00))
140	return 1;
141	else
142	return 0;
143	}
144
145	static int check_edid(unsigned char *edid)
146	{
147	unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
148	unsigned char *b;
149	u32 model;
150	int i, fix = 0, ret = 0;
151
152	manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
153	manufacturer[1] = ((block[0] & 0x03) << 3) +
154	((block[1] & 0xe0) >> 5) + '@';
155	manufacturer[2] = (block[1] & 0x1f) + '@';
156	manufacturer[3] = 0;
157	model = block[2] + (block[3] << 8);
158
159	for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
160	if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
161	brokendb[i].model == model) {
162	fix = brokendb[i].fix;
163	break;
164	}
165	}
166
167	switch (fix) {
168	case FBMON_FIX_HEADER:
169	for (i = 0; i < 8; i++) {
170	if (edid[i] != edid_v1_header[i]) {
171	ret = fix;
172	break;
173	}
174	}
175	break;
176	case FBMON_FIX_INPUT:
177	b = edid + EDID_STRUCT_DISPLAY;
178	/* Only if display is GTF capable will
179	the input type be reset to analog */
180	if (b[4] & 0x01 && b[0] & 0x80)
181	ret = fix;
182	break;
183	case FBMON_FIX_TIMINGS:
184	b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
185	ret = fix;
186
187	for (i = 0; i < 4; i++) {
188	if (edid_is_limits_block(block: b)) {
189	ret = 0;
190	break;
191	}
192
193	b += DETAILED_TIMING_DESCRIPTION_SIZE;
194	}
195
196	break;
197	}
198
199	if (ret)
200	printk("fbmon: The EDID Block of "
201	"Manufacturer: %s Model: 0x%x is known to "
202	"be broken,\n", manufacturer, model);
203
204	return ret;
205	}
206
207	static void fix_edid(unsigned char *edid, int fix)
208	{
209	int i;
210	unsigned char *b, csum = 0;
211
212	switch (fix) {
213	case FBMON_FIX_HEADER:
214	printk("fbmon: trying a header reconstruct\n");
215	memcpy(edid, edid_v1_header, 8);
216	break;
217	case FBMON_FIX_INPUT:
218	printk("fbmon: trying to fix input type\n");
219	b = edid + EDID_STRUCT_DISPLAY;
220	b[0] &= ~0x80;
221	edid[127] += 0x80;
222	break;
223	case FBMON_FIX_TIMINGS:
224	printk("fbmon: trying to fix monitor timings\n");
225	b = edid + DETAILED_TIMING_DESCRIPTIONS_START;
226	for (i = 0; i < 4; i++) {
227	if (!(edid_is_serial_block(block: b) ||
228	edid_is_ascii_block(block: b) ||
229	edid_is_monitor_block(block: b) ||
230	edid_is_timing_block(block: b))) {
231	b[0] = 0x00;
232	b[1] = 0x00;
233	b[2] = 0x00;
234	b[3] = 0xfd;
235	b[4] = 0x00;
236	b[5] = 60; /* vfmin */
237	b[6] = 60; /* vfmax */
238	b[7] = 30; /* hfmin */
239	b[8] = 75; /* hfmax */
240	b[9] = 17; /* pixclock - 170 MHz*/
241	b[10] = 0; /* GTF */
242	break;
243	}
244
245	b += DETAILED_TIMING_DESCRIPTION_SIZE;
246	}
247
248	for (i = 0; i < EDID_LENGTH - 1; i++)
249	csum += edid[i];
250
251	edid[127] = 256 - csum;
252	break;
253	}
254	}
255
256	static int edid_checksum(unsigned char *edid)
257	{
258	unsigned char csum = 0, all_null = 0;
259	int i, err = 0, fix = check_edid(edid);
260
261	if (fix)
262	fix_edid(edid, fix);
263
264	for (i = 0; i < EDID_LENGTH; i++) {
265	csum += edid[i];
266	all_null |= edid[i];
267	}
268
269	if (csum == 0x00 && all_null) {
270	/* checksum passed, everything's good */
271	err = 1;
272	}
273
274	return err;
275	}
276
277	static int edid_check_header(unsigned char *edid)
278	{
279	int i, err = 1, fix = check_edid(edid);
280
281	if (fix)
282	fix_edid(edid, fix);
283
284	for (i = 0; i < 8; i++) {
285	if (edid[i] != edid_v1_header[i])
286	err = 0;
287	}
288
289	return err;
290	}
291
292	static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
293	{
294	specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
295	specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
296	((block[1] & 0xe0) >> 5) + '@';
297	specs->manufacturer[2] = (block[1] & 0x1f) + '@';
298	specs->manufacturer[3] = 0;
299	specs->model = block[2] + (block[3] << 8);
300	specs->serial = block[4] + (block[5] << 8) +
301	(block[6] << 16) + (block[7] << 24);
302	specs->year = block[9] + 1990;
303	specs->week = block[8];
304	DPRINTK(" Manufacturer: %s\n", specs->manufacturer);
305	DPRINTK(" Model: %x\n", specs->model);
306	DPRINTK(" Serial#: %u\n", specs->serial);
307	DPRINTK(" Year: %u Week %u\n", specs->year, specs->week);
308	}
309
310	static void get_dpms_capabilities(unsigned char flags,
311	struct fb_monspecs *specs)
312	{
313	specs->dpms = 0;
314	if (flags & DPMS_ACTIVE_OFF)
315	specs->dpms |= FB_DPMS_ACTIVE_OFF;
316	if (flags & DPMS_SUSPEND)
317	specs->dpms |= FB_DPMS_SUSPEND;
318	if (flags & DPMS_STANDBY)
319	specs->dpms |= FB_DPMS_STANDBY;
320	DPRINTK(" DPMS: Active %s, Suspend %s, Standby %s\n",
321	(flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
322	(flags & DPMS_SUSPEND) ? "yes" : "no",
323	(flags & DPMS_STANDBY) ? "yes" : "no");
324	}
325
326	static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
327	{
328	int tmp;
329
330	DPRINTK(" Chroma\n");
331	/* Chromaticity data */
332	tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
333	tmp *= 1000;
334	tmp += 512;
335	specs->chroma.redx = tmp/1024;
336	DPRINTK(" RedX: 0.%03d ", specs->chroma.redx);
337
338	tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
339	tmp *= 1000;
340	tmp += 512;
341	specs->chroma.redy = tmp/1024;
342	DPRINTK("RedY: 0.%03d\n", specs->chroma.redy);
343
344	tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
345	tmp *= 1000;
346	tmp += 512;
347	specs->chroma.greenx = tmp/1024;
348	DPRINTK(" GreenX: 0.%03d ", specs->chroma.greenx);
349
350	tmp = (block[5] & 3) | (block[0xa] << 2);
351	tmp *= 1000;
352	tmp += 512;
353	specs->chroma.greeny = tmp/1024;
354	DPRINTK("GreenY: 0.%03d\n", specs->chroma.greeny);
355
356	tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
357	tmp *= 1000;
358	tmp += 512;
359	specs->chroma.bluex = tmp/1024;
360	DPRINTK(" BlueX: 0.%03d ", specs->chroma.bluex);
361
362	tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
363	tmp *= 1000;
364	tmp += 512;
365	specs->chroma.bluey = tmp/1024;
366	DPRINTK("BlueY: 0.%03d\n", specs->chroma.bluey);
367
368	tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
369	tmp *= 1000;
370	tmp += 512;
371	specs->chroma.whitex = tmp/1024;
372	DPRINTK(" WhiteX: 0.%03d ", specs->chroma.whitex);
373
374	tmp = (block[6] & 3) | (block[0xe] << 2);
375	tmp *= 1000;
376	tmp += 512;
377	specs->chroma.whitey = tmp/1024;
378	DPRINTK("WhiteY: 0.%03d\n", specs->chroma.whitey);
379	}
380
381	static void calc_mode_timings(int xres, int yres, int refresh,
382	struct fb_videomode *mode)
383	{
384	struct fb_var_screeninfo *var;
385
386	var = kzalloc(size: sizeof(struct fb_var_screeninfo), GFP_KERNEL);
387
388	if (var) {
389	var->xres = xres;
390	var->yres = yres;
391	fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON,
392	val: refresh, var, NULL);
393	mode->xres = xres;
394	mode->yres = yres;
395	mode->pixclock = var->pixclock;
396	mode->refresh = refresh;
397	mode->left_margin = var->left_margin;
398	mode->right_margin = var->right_margin;
399	mode->upper_margin = var->upper_margin;
400	mode->lower_margin = var->lower_margin;
401	mode->hsync_len = var->hsync_len;
402	mode->vsync_len = var->vsync_len;
403	mode->vmode = 0;
404	mode->sync = 0;
405	kfree(objp: var);
406	}
407	}
408
409	static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
410	{
411	int num = 0;
412	unsigned char c;
413
414	c = block[0];
415	if (c&0x80) {
416	calc_mode_timings(xres: 720, yres: 400, refresh: 70, mode: &mode[num]);
417	mode[num++].flag = FB_MODE_IS_CALCULATED;
418	DPRINTK(" 720x400@70Hz\n");
419	}
420	if (c&0x40) {
421	calc_mode_timings(xres: 720, yres: 400, refresh: 88, mode: &mode[num]);
422	mode[num++].flag = FB_MODE_IS_CALCULATED;
423	DPRINTK(" 720x400@88Hz\n");
424	}
425	if (c&0x20) {
426	mode[num++] = vesa_modes[3];
427	DPRINTK(" 640x480@60Hz\n");
428	}
429	if (c&0x10) {
430	calc_mode_timings(xres: 640, yres: 480, refresh: 67, mode: &mode[num]);
431	mode[num++].flag = FB_MODE_IS_CALCULATED;
432	DPRINTK(" 640x480@67Hz\n");
433	}
434	if (c&0x08) {
435	mode[num++] = vesa_modes[4];
436	DPRINTK(" 640x480@72Hz\n");
437	}
438	if (c&0x04) {
439	mode[num++] = vesa_modes[5];
440	DPRINTK(" 640x480@75Hz\n");
441	}
442	if (c&0x02) {
443	mode[num++] = vesa_modes[7];
444	DPRINTK(" 800x600@56Hz\n");
445	}
446	if (c&0x01) {
447	mode[num++] = vesa_modes[8];
448	DPRINTK(" 800x600@60Hz\n");
449	}
450
451	c = block[1];
452	if (c&0x80) {
453	mode[num++] = vesa_modes[9];
454	DPRINTK(" 800x600@72Hz\n");
455	}
456	if (c&0x40) {
457	mode[num++] = vesa_modes[10];
458	DPRINTK(" 800x600@75Hz\n");
459	}
460	if (c&0x20) {
461	calc_mode_timings(xres: 832, yres: 624, refresh: 75, mode: &mode[num]);
462	mode[num++].flag = FB_MODE_IS_CALCULATED;
463	DPRINTK(" 832x624@75Hz\n");
464	}
465	if (c&0x10) {
466	mode[num++] = vesa_modes[12];
467	DPRINTK(" 1024x768@87Hz Interlaced\n");
468	}
469	if (c&0x08) {
470	mode[num++] = vesa_modes[13];
471	DPRINTK(" 1024x768@60Hz\n");
472	}
473	if (c&0x04) {
474	mode[num++] = vesa_modes[14];
475	DPRINTK(" 1024x768@70Hz\n");
476	}
477	if (c&0x02) {
478	mode[num++] = vesa_modes[15];
479	DPRINTK(" 1024x768@75Hz\n");
480	}
481	if (c&0x01) {
482	mode[num++] = vesa_modes[21];
483	DPRINTK(" 1280x1024@75Hz\n");
484	}
485	c = block[2];
486	if (c&0x80) {
487	mode[num++] = vesa_modes[17];
488	DPRINTK(" 1152x870@75Hz\n");
489	}
490	DPRINTK(" Manufacturer's mask: %x\n",c&0x7F);
491	return num;
492	}
493
494	static int get_std_timing(unsigned char *block, struct fb_videomode *mode,
495	int ver, int rev, const struct fb_monspecs *specs)
496	{
497	int i;
498
499	for (i = 0; i < DMT_SIZE; i++) {
500	u32 std_2byte_code = block[0] << 8 | block[1];
501	if (std_2byte_code == dmt_modes[i].std_2byte_code)
502	break;
503	}
504
505	if (i < DMT_SIZE && dmt_modes[i].mode) {
506	/* DMT mode found */
507	*mode = *dmt_modes[i].mode;
508	mode->flag |= FB_MODE_IS_STANDARD;
509	DPRINTK(" DMT id=%d\n", dmt_modes[i].dmt_id);
510
511	} else {
512	int xres, yres = 0, refresh, ratio;
513
514	xres = (block[0] + 31) * 8;
515	if (xres <= 256)
516	return 0;
517
518	ratio = (block[1] & 0xc0) >> 6;
519	switch (ratio) {
520	case 0:
521	/* in EDID 1.3 the meaning of 0 changed to 16:10 (prior 1:1) */
522	if (ver < 1 || (ver == 1 && rev < 3))
523	yres = xres;
524	else
525	yres = (xres * 10)/16;
526	break;
527	case 1:
528	yres = (xres * 3)/4;
529	break;
530	case 2:
531	yres = (xres * 4)/5;
532	break;
533	case 3:
534	yres = (xres * 9)/16;
535	break;
536	}
537	refresh = (block[1] & 0x3f) + 60;
538	DPRINTK(" %dx%d@%dHz\n", xres, yres, refresh);
539
540	calc_mode_timings(xres, yres, refresh, mode);
541	}
542
543	/* Check the mode we got is within valid spec of the monitor */
544	if (specs && specs->dclkmax
545	&& PICOS2KHZ(mode->pixclock) * 1000 > specs->dclkmax) {
546	DPRINTK(" mode exceed max DCLK\n");
547	return 0;
548	}
549
550	return 1;
551	}
552
553	static int get_dst_timing(unsigned char *block, struct fb_videomode *mode,
554	int ver, int rev, const struct fb_monspecs *specs)
555	{
556	int j, num = 0;
557
558	for (j = 0; j < 6; j++, block += STD_TIMING_DESCRIPTION_SIZE)
559	num += get_std_timing(block, mode: &mode[num], ver, rev, specs);
560
561	return num;
562	}
563
564	static void get_detailed_timing(unsigned char *block,
565	struct fb_videomode *mode)
566	{
567	mode->xres = H_ACTIVE;
568	mode->yres = V_ACTIVE;
569	mode->pixclock = PIXEL_CLOCK;
570	mode->pixclock /= 1000;
571	mode->pixclock = KHZ2PICOS(mode->pixclock);
572	mode->right_margin = H_SYNC_OFFSET;
573	mode->left_margin = (H_ACTIVE + H_BLANKING) -
574	(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
575	mode->upper_margin = V_BLANKING - V_SYNC_OFFSET -
576	V_SYNC_WIDTH;
577	mode->lower_margin = V_SYNC_OFFSET;
578	mode->hsync_len = H_SYNC_WIDTH;
579	mode->vsync_len = V_SYNC_WIDTH;
580	if (HSYNC_POSITIVE)
581	mode->sync |= FB_SYNC_HOR_HIGH_ACT;
582	if (VSYNC_POSITIVE)
583	mode->sync |= FB_SYNC_VERT_HIGH_ACT;
584	mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
585	(V_ACTIVE + V_BLANKING));
586	if (INTERLACED) {
587	mode->yres *= 2;
588	mode->upper_margin *= 2;
589	mode->lower_margin *= 2;
590	mode->vsync_len *= 2;
591	mode->vmode |= FB_VMODE_INTERLACED;
592	}
593	mode->flag = FB_MODE_IS_DETAILED;
594
595	DPRINTK(" %d MHz ", PIXEL_CLOCK/1000000);
596	DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
597	H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
598	DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
599	V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
600	DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
601	(VSYNC_POSITIVE) ? "+" : "-");
602	}
603
604	/**
605	* fb_create_modedb - create video mode database
606	* @edid: EDID data
607	* @dbsize: database size
608	* @specs: monitor specifications, may be NULL
609	*
610	* RETURNS: struct fb_videomode, @dbsize contains length of database
611	*
612	* DESCRIPTION:
613	* This function builds a mode database using the contents of the EDID
614	* data
615	*/
616	static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize,
617	const struct fb_monspecs *specs)
618	{
619	struct fb_videomode *mode, *m;
620	unsigned char *block;
621	int num = 0, i, first = 1;
622	int ver, rev;
623
624	mode = kcalloc(n: 50, size: sizeof(struct fb_videomode), GFP_KERNEL);
625	if (mode == NULL)
626	return NULL;
627
628	if (edid == NULL || !edid_checksum(edid) ||
629	!edid_check_header(edid)) {
630	kfree(objp: mode);
631	return NULL;
632	}
633
634	ver = edid[EDID_STRUCT_VERSION];
635	rev = edid[EDID_STRUCT_REVISION];
636
637	*dbsize = 0;
638
639	DPRINTK(" Detailed Timings\n");
640	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
641	for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
642	if (!(block[0] == 0x00 && block[1] == 0x00)) {
643	get_detailed_timing(block, mode: &mode[num]);
644	if (first) {
645	mode[num].flag |= FB_MODE_IS_FIRST;
646	first = 0;
647	}
648	num++;
649	}
650	}
651
652	DPRINTK(" Supported VESA Modes\n");
653	block = edid + ESTABLISHED_TIMING_1;
654	num += get_est_timing(block, mode: &mode[num]);
655
656	DPRINTK(" Standard Timings\n");
657	block = edid + STD_TIMING_DESCRIPTIONS_START;
658	for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE)
659	num += get_std_timing(block, mode: &mode[num], ver, rev, specs);
660
661	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
662	for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
663	if (block[0] == 0x00 && block[1] == 0x00 && block[3] == 0xfa)
664	num += get_dst_timing(block: block + 5, mode: &mode[num],
665	ver, rev, specs);
666	}
667
668	/* Yikes, EDID data is totally useless */
669	if (!num) {
670	kfree(objp: mode);
671	return NULL;
672	}
673
674	*dbsize = num;
675	m = kmalloc_array(n: num, size: sizeof(struct fb_videomode), GFP_KERNEL);
676	if (!m)
677	return mode;
678	memmove(m, mode, num * sizeof(struct fb_videomode));
679	kfree(objp: mode);
680	return m;
681	}
682
683	/**
684	* fb_destroy_modedb - destroys mode database
685	* @modedb: mode database to destroy
686	*
687	* DESCRIPTION:
688	* Destroy mode database created by fb_create_modedb
689	*/
690	void fb_destroy_modedb(struct fb_videomode *modedb)
691	{
692	kfree(objp: modedb);
693	}
694
695	static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
696	{
697	int i, retval = 1;
698	unsigned char *block;
699
700	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
701
702	DPRINTK(" Monitor Operating Limits: ");
703
704	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
705	if (edid_is_limits_block(block)) {
706	specs->hfmin = H_MIN_RATE * 1000;
707	specs->hfmax = H_MAX_RATE * 1000;
708	specs->vfmin = V_MIN_RATE;
709	specs->vfmax = V_MAX_RATE;
710	specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
711	specs->gtf = (GTF_SUPPORT) ? 1 : 0;
712	retval = 0;
713	DPRINTK("From EDID\n");
714	break;
715	}
716	}
717
718	/* estimate monitor limits based on modes supported */
719	if (retval) {
720	struct fb_videomode *modes, *mode;
721	int num_modes, hz, hscan, pixclock;
722	int vtotal, htotal;
723
724	modes = fb_create_modedb(edid, dbsize: &num_modes, specs);
725	if (!modes) {
726	DPRINTK("None Available\n");
727	return 1;
728	}
729
730	retval = 0;
731	for (i = 0; i < num_modes; i++) {
732	mode = &modes[i];
733	pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
734	htotal = mode->xres + mode->right_margin + mode->hsync_len
735	+ mode->left_margin;
736	vtotal = mode->yres + mode->lower_margin + mode->vsync_len
737	+ mode->upper_margin;
738
739	if (mode->vmode & FB_VMODE_INTERLACED)
740	vtotal /= 2;
741
742	if (mode->vmode & FB_VMODE_DOUBLE)
743	vtotal *= 2;
744
745	hscan = (pixclock + htotal / 2) / htotal;
746	hscan = (hscan + 500) / 1000 * 1000;
747	hz = (hscan + vtotal / 2) / vtotal;
748
749	if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
750	specs->dclkmax = pixclock;
751
752	if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
753	specs->dclkmin = pixclock;
754
755	if (specs->hfmax == 0 || specs->hfmax < hscan)
756	specs->hfmax = hscan;
757
758	if (specs->hfmin == 0 || specs->hfmin > hscan)
759	specs->hfmin = hscan;
760
761	if (specs->vfmax == 0 || specs->vfmax < hz)
762	specs->vfmax = hz;
763
764	if (specs->vfmin == 0 || specs->vfmin > hz)
765	specs->vfmin = hz;
766	}
767	DPRINTK("Extrapolated\n");
768	fb_destroy_modedb(modedb: modes);
769	}
770	DPRINTK(" H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
771	specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
772	specs->vfmax, specs->dclkmax/1000000);
773	return retval;
774	}
775
776	static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
777	{
778	unsigned char c, *block;
779
780	block = edid + EDID_STRUCT_DISPLAY;
781
782	fb_get_monitor_limits(edid, specs);
783
784	c = block[0] & 0x80;
785	specs->input = 0;
786	if (c) {
787	specs->input |= FB_DISP_DDI;
788	DPRINTK(" Digital Display Input");
789	} else {
790	DPRINTK(" Analog Display Input: Input Voltage - ");
791	switch ((block[0] & 0x60) >> 5) {
792	case 0:
793	DPRINTK("0.700V/0.300V");
794	specs->input |= FB_DISP_ANA_700_300;
795	break;
796	case 1:
797	DPRINTK("0.714V/0.286V");
798	specs->input |= FB_DISP_ANA_714_286;
799	break;
800	case 2:
801	DPRINTK("1.000V/0.400V");
802	specs->input |= FB_DISP_ANA_1000_400;
803	break;
804	case 3:
805	DPRINTK("0.700V/0.000V");
806	specs->input |= FB_DISP_ANA_700_000;
807	break;
808	}
809	}
810	DPRINTK("\n Sync: ");
811	c = block[0] & 0x10;
812	if (c)
813	DPRINTK(" Configurable signal level\n");
814	c = block[0] & 0x0f;
815	specs->signal = 0;
816	if (c & 0x10) {
817	DPRINTK("Blank to Blank ");
818	specs->signal |= FB_SIGNAL_BLANK_BLANK;
819	}
820	if (c & 0x08) {
821	DPRINTK("Separate ");
822	specs->signal |= FB_SIGNAL_SEPARATE;
823	}
824	if (c & 0x04) {
825	DPRINTK("Composite ");
826	specs->signal |= FB_SIGNAL_COMPOSITE;
827	}
828	if (c & 0x02) {
829	DPRINTK("Sync on Green ");
830	specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
831	}
832	if (c & 0x01) {
833	DPRINTK("Serration on ");
834	specs->signal |= FB_SIGNAL_SERRATION_ON;
835	}
836	DPRINTK("\n");
837	specs->max_x = block[1];
838	specs->max_y = block[2];
839	DPRINTK(" Max H-size in cm: ");
840	if (specs->max_x)
841	DPRINTK("%d\n", specs->max_x);
842	else
843	DPRINTK("variable\n");
844	DPRINTK(" Max V-size in cm: ");
845	if (specs->max_y)
846	DPRINTK("%d\n", specs->max_y);
847	else
848	DPRINTK("variable\n");
849
850	c = block[3];
851	specs->gamma = c+100;
852	DPRINTK(" Gamma: ");
853	DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
854
855	get_dpms_capabilities(flags: block[4], specs);
856
857	switch ((block[4] & 0x18) >> 3) {
858	case 0:
859	DPRINTK(" Monochrome/Grayscale\n");
860	specs->input |= FB_DISP_MONO;
861	break;
862	case 1:
863	DPRINTK(" RGB Color Display\n");
864	specs->input |= FB_DISP_RGB;
865	break;
866	case 2:
867	DPRINTK(" Non-RGB Multicolor Display\n");
868	specs->input |= FB_DISP_MULTI;
869	break;
870	default:
871	DPRINTK(" Unknown\n");
872	specs->input |= FB_DISP_UNKNOWN;
873	break;
874	}
875
876	get_chroma(block, specs);
877
878	specs->misc = 0;
879	c = block[4] & 0x7;
880	if (c & 0x04) {
881	DPRINTK(" Default color format is primary\n");
882	specs->misc |= FB_MISC_PRIM_COLOR;
883	}
884	if (c & 0x02) {
885	DPRINTK(" First DETAILED Timing is preferred\n");
886	specs->misc |= FB_MISC_1ST_DETAIL;
887	}
888	if (c & 0x01) {
889	printk(" Display is GTF capable\n");
890	specs->gtf = 1;
891	}
892	}
893
894	int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
895	{
896	int i;
897	unsigned char *block;
898
899	if (edid == NULL || var == NULL)
900	return 1;
901
902	if (!(edid_checksum(edid)))
903	return 1;
904
905	if (!(edid_check_header(edid)))
906	return 1;
907
908	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
909
910	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
911	if (edid_is_timing_block(block)) {
912	var->xres = var->xres_virtual = H_ACTIVE;
913	var->yres = var->yres_virtual = V_ACTIVE;
914	var->height = var->width = 0;
915	var->right_margin = H_SYNC_OFFSET;
916	var->left_margin = (H_ACTIVE + H_BLANKING) -
917	(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
918	var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
919	V_SYNC_WIDTH;
920	var->lower_margin = V_SYNC_OFFSET;
921	var->hsync_len = H_SYNC_WIDTH;
922	var->vsync_len = V_SYNC_WIDTH;
923	var->pixclock = PIXEL_CLOCK;
924	var->pixclock /= 1000;
925	var->pixclock = KHZ2PICOS(var->pixclock);
926
927	if (HSYNC_POSITIVE)
928	var->sync |= FB_SYNC_HOR_HIGH_ACT;
929	if (VSYNC_POSITIVE)
930	var->sync |= FB_SYNC_VERT_HIGH_ACT;
931	return 0;
932	}
933	}
934	return 1;
935	}
936
937	void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
938	{
939	unsigned char *block;
940	int i, found = 0;
941
942	if (edid == NULL)
943	return;
944
945	if (!(edid_checksum(edid)))
946	return;
947
948	if (!(edid_check_header(edid)))
949	return;
950
951	memset(specs, 0, sizeof(struct fb_monspecs));
952
953	specs->version = edid[EDID_STRUCT_VERSION];
954	specs->revision = edid[EDID_STRUCT_REVISION];
955
956	DPRINTK("========================================\n");
957	DPRINTK("Display Information (EDID)\n");
958	DPRINTK("========================================\n");
959	DPRINTK(" EDID Version %d.%d\n", (int) specs->version,
960	(int) specs->revision);
961
962	parse_vendor_block(block: edid + ID_MANUFACTURER_NAME, specs);
963
964	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
965	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
966	if (edid_is_serial_block(block)) {
967	copy_string(c: block, s: specs->serial_no);
968	DPRINTK(" Serial Number: %s\n", specs->serial_no);
969	} else if (edid_is_ascii_block(block)) {
970	copy_string(c: block, s: specs->ascii);
971	DPRINTK(" ASCII Block: %s\n", specs->ascii);
972	} else if (edid_is_monitor_block(block)) {
973	copy_string(c: block, s: specs->monitor);
974	DPRINTK(" Monitor Name: %s\n", specs->monitor);
975	}
976	}
977
978	DPRINTK(" Display Characteristics:\n");
979	get_monspecs(edid, specs);
980
981	specs->modedb = fb_create_modedb(edid, dbsize: &specs->modedb_len, specs);
982	if (!specs->modedb)
983	return;
984
985	/*
986	* Workaround for buggy EDIDs that sets that the first
987	* detailed timing is preferred but has not detailed
988	* timing specified
989	*/
990	for (i = 0; i < specs->modedb_len; i++) {
991	if (specs->modedb[i].flag & FB_MODE_IS_DETAILED) {
992	found = 1;
993	break;
994	}
995	}
996
997	if (!found)
998	specs->misc &= ~FB_MISC_1ST_DETAIL;
999
1000	DPRINTK("========================================\n");
1001	}
1002
1003	/*
1004	* VESA Generalized Timing Formula (GTF)
1005	*/
1006
1007	#define FLYBACK 550
1008	#define V_FRONTPORCH 1
1009	#define H_OFFSET 40
1010	#define H_SCALEFACTOR 20
1011	#define H_BLANKSCALE 128
1012	#define H_GRADIENT 600
1013	#define C_VAL 30
1014	#define M_VAL 300
1015
1016	struct __fb_timings {
1017	u32 dclk;
1018	u32 hfreq;
1019	u32 vfreq;
1020	u32 hactive;
1021	u32 vactive;
1022	u32 hblank;
1023	u32 vblank;
1024	u32 htotal;
1025	u32 vtotal;
1026	};
1027
1028	/**
1029	* fb_get_vblank - get vertical blank time
1030	* @hfreq: horizontal freq
1031	*
1032	* DESCRIPTION:
1033	* vblank = right_margin + vsync_len + left_margin
1034	*
1035	* given: right_margin = 1 (V_FRONTPORCH)
1036	* vsync_len = 3
1037	* flyback = 550
1038	*
1039	* flyback * hfreq
1040	* left_margin = --------------- - vsync_len
1041	* 1000000
1042	*/
1043	static u32 fb_get_vblank(u32 hfreq)
1044	{
1045	u32 vblank;
1046
1047	vblank = (hfreq * FLYBACK)/1000;
1048	vblank = (vblank + 500)/1000;
1049	return (vblank + V_FRONTPORCH);
1050	}
1051
1052	/**
1053	* fb_get_hblank_by_hfreq - get horizontal blank time given hfreq
1054	* @hfreq: horizontal freq
1055	* @xres: horizontal resolution in pixels
1056	*
1057	* DESCRIPTION:
1058	*
1059	* xres * duty_cycle
1060	* hblank = ------------------
1061	* 100 - duty_cycle
1062	*
1063	* duty cycle = percent of htotal assigned to inactive display
1064	* duty cycle = C - (M/Hfreq)
1065	*
1066	* where: C = ((offset - scale factor) * blank_scale)
1067	* -------------------------------------- + scale factor
1068	* 256
1069	* M = blank_scale * gradient
1070	*
1071	*/
1072	static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
1073	{
1074	u32 c_val, m_val, duty_cycle, hblank;
1075
1076	c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 +
1077	H_SCALEFACTOR) * 1000;
1078	m_val = (H_BLANKSCALE * H_GRADIENT)/256;
1079	m_val = (m_val * 1000000)/hfreq;
1080	duty_cycle = c_val - m_val;
1081	hblank = (xres * duty_cycle)/(100000 - duty_cycle);
1082	return (hblank);
1083	}
1084
1085	/**
1086	* fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
1087	* @dclk: pixelclock in Hz
1088	* @xres: horizontal resolution in pixels
1089	*
1090	* DESCRIPTION:
1091	*
1092	* xres * duty_cycle
1093	* hblank = ------------------
1094	* 100 - duty_cycle
1095	*
1096	* duty cycle = percent of htotal assigned to inactive display
1097	* duty cycle = C - (M * h_period)
1098	*
1099	* where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
1100	* -----------------------------------------------
1101	* 2 * M
1102	* M = 300;
1103	* C = 30;
1104	*/
1105	static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
1106	{
1107	u32 duty_cycle, h_period, hblank;
1108
1109	dclk /= 1000;
1110	h_period = 100 - C_VAL;
1111	h_period *= h_period;
1112	h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
1113	h_period *= 10000;
1114
1115	h_period = int_sqrt(h_period);
1116	h_period -= (100 - C_VAL) * 100;
1117	h_period *= 1000;
1118	h_period /= 2 * M_VAL;
1119
1120	duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
1121	hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
1122	hblank &= ~15;
1123	return (hblank);
1124	}
1125
1126	/**
1127	* fb_get_hfreq - estimate hsync
1128	* @vfreq: vertical refresh rate
1129	* @yres: vertical resolution
1130	*
1131	* DESCRIPTION:
1132	*
1133	* (yres + front_port) * vfreq * 1000000
1134	* hfreq = -------------------------------------
1135	* (1000000 - (vfreq * FLYBACK)
1136	*
1137	*/
1138
1139	static u32 fb_get_hfreq(u32 vfreq, u32 yres)
1140	{
1141	u32 divisor, hfreq;
1142
1143	divisor = (1000000 - (vfreq * FLYBACK))/1000;
1144	hfreq = (yres + V_FRONTPORCH) * vfreq * 1000;
1145	return (hfreq/divisor);
1146	}
1147
1148	static void fb_timings_vfreq(struct __fb_timings *timings)
1149	{
1150	timings->hfreq = fb_get_hfreq(vfreq: timings->vfreq, yres: timings->vactive);
1151	timings->vblank = fb_get_vblank(hfreq: timings->hfreq);
1152	timings->vtotal = timings->vactive + timings->vblank;
1153	timings->hblank = fb_get_hblank_by_hfreq(hfreq: timings->hfreq,
1154	xres: timings->hactive);
1155	timings->htotal = timings->hactive + timings->hblank;
1156	timings->dclk = timings->htotal * timings->hfreq;
1157	}
1158
1159	static void fb_timings_hfreq(struct __fb_timings *timings)
1160	{
1161	timings->vblank = fb_get_vblank(hfreq: timings->hfreq);
1162	timings->vtotal = timings->vactive + timings->vblank;
1163	timings->vfreq = timings->hfreq/timings->vtotal;
1164	timings->hblank = fb_get_hblank_by_hfreq(hfreq: timings->hfreq,
1165	xres: timings->hactive);
1166	timings->htotal = timings->hactive + timings->hblank;
1167	timings->dclk = timings->htotal * timings->hfreq;
1168	}
1169
1170	static void fb_timings_dclk(struct __fb_timings *timings)
1171	{
1172	timings->hblank = fb_get_hblank_by_dclk(dclk: timings->dclk,
1173	xres: timings->hactive);
1174	timings->htotal = timings->hactive + timings->hblank;
1175	timings->hfreq = timings->dclk/timings->htotal;
1176	timings->vblank = fb_get_vblank(hfreq: timings->hfreq);
1177	timings->vtotal = timings->vactive + timings->vblank;
1178	timings->vfreq = timings->hfreq/timings->vtotal;
1179	}
1180
1181	/*
1182	* fb_get_mode - calculates video mode using VESA GTF
1183	* @flags: if: 0 - maximize vertical refresh rate
1184	* 1 - vrefresh-driven calculation;
1185	* 2 - hscan-driven calculation;
1186	* 3 - pixelclock-driven calculation;
1187	* @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
1188	* @var: pointer to fb_var_screeninfo
1189	* @info: pointer to fb_info
1190	*
1191	* DESCRIPTION:
1192	* Calculates video mode based on monitor specs using VESA GTF.
1193	* The GTF is best for VESA GTF compliant monitors but is
1194	* specifically formulated to work for older monitors as well.
1195	*
1196	* If @flag==0, the function will attempt to maximize the
1197	* refresh rate. Otherwise, it will calculate timings based on
1198	* the flag and accompanying value.
1199	*
1200	* If FB_IGNOREMON bit is set in @flags, monitor specs will be
1201	* ignored and @var will be filled with the calculated timings.
1202	*
1203	* All calculations are based on the VESA GTF Spreadsheet
1204	* available at VESA's public ftp (https://www.vesa.org).
1205	*
1206	* NOTES:
1207	* The timings generated by the GTF will be different from VESA
1208	* DMT. It might be a good idea to keep a table of standard
1209	* VESA modes as well. The GTF may also not work for some displays,
1210	* such as, and especially, analog TV.
1211	*
1212	* REQUIRES:
1213	* A valid info->monspecs, otherwise 'safe numbers' will be used.
1214	*/
1215	int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
1216	{
1217	struct __fb_timings *timings;
1218	u32 interlace = 1, dscan = 1;
1219	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax, err = 0;
1220
1221
1222	timings = kzalloc(size: sizeof(struct __fb_timings), GFP_KERNEL);
1223
1224	if (!timings)
1225	return -ENOMEM;
1226
1227	/*
1228	* If monspecs are invalid, use values that are enough
1229	* for 640x480@60
1230	*/
1231	if (!info || !info->monspecs.hfmax || !info->monspecs.vfmax ||
1232	!info->monspecs.dclkmax ||
1233	info->monspecs.hfmax < info->monspecs.hfmin ||
1234	info->monspecs.vfmax < info->monspecs.vfmin ||
1235	info->monspecs.dclkmax < info->monspecs.dclkmin) {
1236	hfmin = 29000; hfmax = 30000;
1237	vfmin = 60; vfmax = 60;
1238	dclkmin = 0; dclkmax = 25000000;
1239	} else {
1240	hfmin = info->monspecs.hfmin;
1241	hfmax = info->monspecs.hfmax;
1242	vfmin = info->monspecs.vfmin;
1243	vfmax = info->monspecs.vfmax;
1244	dclkmin = info->monspecs.dclkmin;
1245	dclkmax = info->monspecs.dclkmax;
1246	}
1247
1248	timings->hactive = var->xres;
1249	timings->vactive = var->yres;
1250	if (var->vmode & FB_VMODE_INTERLACED) {
1251	timings->vactive /= 2;
1252	interlace = 2;
1253	}
1254	if (var->vmode & FB_VMODE_DOUBLE) {
1255	timings->vactive *= 2;
1256	dscan = 2;
1257	}
1258
1259	switch (flags & ~FB_IGNOREMON) {
1260	case FB_MAXTIMINGS: /* maximize refresh rate */
1261	timings->hfreq = hfmax;
1262	fb_timings_hfreq(timings);
1263	if (timings->vfreq > vfmax) {
1264	timings->vfreq = vfmax;
1265	fb_timings_vfreq(timings);
1266	}
1267	if (timings->dclk > dclkmax) {
1268	timings->dclk = dclkmax;
1269	fb_timings_dclk(timings);
1270	}
1271	break;
1272	case FB_VSYNCTIMINGS: /* vrefresh driven */
1273	timings->vfreq = val;
1274	fb_timings_vfreq(timings);
1275	break;
1276	case FB_HSYNCTIMINGS: /* hsync driven */
1277	timings->hfreq = val;
1278	fb_timings_hfreq(timings);
1279	break;
1280	case FB_DCLKTIMINGS: /* pixelclock driven */
1281	timings->dclk = PICOS2KHZ(val) * 1000;
1282	fb_timings_dclk(timings);
1283	break;
1284	default:
1285	err = -EINVAL;
1286
1287	}
1288
1289	if (err || (!(flags & FB_IGNOREMON) &&
1290	(timings->vfreq < vfmin || timings->vfreq > vfmax ||
1291	timings->hfreq < hfmin || timings->hfreq > hfmax ||
1292	timings->dclk < dclkmin || timings->dclk > dclkmax))) {
1293	err = -EINVAL;
1294	} else {
1295	var->pixclock = KHZ2PICOS(timings->dclk/1000);
1296	var->hsync_len = (timings->htotal * 8)/100;
1297	var->right_margin = (timings->hblank/2) - var->hsync_len;
1298	var->left_margin = timings->hblank - var->right_margin -
1299	var->hsync_len;
1300	var->vsync_len = (3 * interlace)/dscan;
1301	var->lower_margin = (1 * interlace)/dscan;
1302	var->upper_margin = (timings->vblank * interlace)/dscan -
1303	(var->vsync_len + var->lower_margin);
1304	}
1305
1306	kfree(objp: timings);
1307	return err;
1308	}
1309
1310	#ifdef CONFIG_VIDEOMODE_HELPERS
1311	int fb_videomode_from_videomode(const struct videomode *vm,
1312	struct fb_videomode *fbmode)
1313	{
1314	unsigned int htotal, vtotal, total;
1315
1316	fbmode->xres = vm->hactive;
1317	fbmode->left_margin = vm->hback_porch;
1318	fbmode->right_margin = vm->hfront_porch;
1319	fbmode->hsync_len = vm->hsync_len;
1320
1321	fbmode->yres = vm->vactive;
1322	fbmode->upper_margin = vm->vback_porch;
1323	fbmode->lower_margin = vm->vfront_porch;
1324	fbmode->vsync_len = vm->vsync_len;
1325
1326	/* prevent division by zero in KHZ2PICOS macro */
1327	fbmode->pixclock = vm->pixelclock ?
1328	KHZ2PICOS(vm->pixelclock / 1000) : 0;
1329
1330	fbmode->sync = 0;
1331	fbmode->vmode = 0;
1332	if (vm->flags & DISPLAY_FLAGS_HSYNC_HIGH)
1333	fbmode->sync |= FB_SYNC_HOR_HIGH_ACT;
1334	if (vm->flags & DISPLAY_FLAGS_VSYNC_HIGH)
1335	fbmode->sync |= FB_SYNC_VERT_HIGH_ACT;
1336	if (vm->flags & DISPLAY_FLAGS_INTERLACED)
1337	fbmode->vmode |= FB_VMODE_INTERLACED;
1338	if (vm->flags & DISPLAY_FLAGS_DOUBLESCAN)
1339	fbmode->vmode |= FB_VMODE_DOUBLE;
1340	fbmode->flag = 0;
1341
1342	htotal = vm->hactive + vm->hfront_porch + vm->hback_porch +
1343	vm->hsync_len;
1344	vtotal = vm->vactive + vm->vfront_porch + vm->vback_porch +
1345	vm->vsync_len;
1346	/* prevent division by zero */
1347	total = htotal * vtotal;
1348	if (total) {
1349	fbmode->refresh = vm->pixelclock / total;
1350	/* a mode must have htotal and vtotal != 0 or it is invalid */
1351	} else {
1352	fbmode->refresh = 0;
1353	return -EINVAL;
1354	}
1355
1356	return 0;
1357	}
1358	EXPORT_SYMBOL_GPL(fb_videomode_from_videomode);
1359
1360	#ifdef CONFIG_OF
1361	static inline void dump_fb_videomode(const struct fb_videomode *m)
1362	{
1363	pr_debug("fb_videomode = %ux%u@%uHz (%ukHz) %u %u %u %u %u %u %u %u %u\n",
1364	m->xres, m->yres, m->refresh, m->pixclock, m->left_margin,
1365	m->right_margin, m->upper_margin, m->lower_margin,
1366	m->hsync_len, m->vsync_len, m->sync, m->vmode, m->flag);
1367	}
1368
1369	/**
1370	* of_get_fb_videomode - get a fb_videomode from devicetree
1371	* @np: device_node with the timing specification
1372	* @fb: will be set to the return value
1373	* @index: index into the list of display timings in devicetree
1374	*
1375	* DESCRIPTION:
1376	* This function is expensive and should only be used, if only one mode is to be
1377	* read from DT. To get multiple modes start with of_get_display_timings ond
1378	* work with that instead.
1379	*/
1380	int of_get_fb_videomode(struct device_node *np, struct fb_videomode *fb,
1381	int index)
1382	{
1383	struct videomode vm;
1384	int ret;
1385
1386	ret = of_get_videomode(np, vm: &vm, index);
1387	if (ret)
1388	return ret;
1389
1390	ret = fb_videomode_from_videomode(&vm, fb);
1391	if (ret)
1392	return ret;
1393
1394	pr_debug("%pOF: got %dx%d display mode\n",
1395	np, vm.hactive, vm.vactive);
1396	dump_fb_videomode(m: fb);
1397
1398	return 0;
1399	}
1400	EXPORT_SYMBOL_GPL(of_get_fb_videomode);
1401	#endif /* CONFIG_OF */
1402	#endif /* CONFIG_VIDEOMODE_HELPERS */
1403
1404	#else
1405	int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
1406	{
1407	return 1;
1408	}
1409	void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
1410	{
1411	}
1412	void fb_destroy_modedb(struct fb_videomode *modedb)
1413	{
1414	}
1415	int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
1416	struct fb_info *info)
1417	{
1418	return -EINVAL;
1419	}
1420	#endif /* CONFIG_FB_MODE_HELPERS */
1421
1422	/*
1423	* fb_validate_mode - validates var against monitor capabilities
1424	* @var: pointer to fb_var_screeninfo
1425	* @info: pointer to fb_info
1426	*
1427	* DESCRIPTION:
1428	* Validates video mode against monitor capabilities specified in
1429	* info->monspecs.
1430	*
1431	* REQUIRES:
1432	* A valid info->monspecs.
1433	*/
1434	int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
1435	{
1436	u32 hfreq, vfreq, htotal, vtotal, pixclock;
1437	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
1438
1439	/*
1440	* If monspecs are invalid, use values that are enough
1441	* for 640x480@60
1442	*/
1443	if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
1444	!info->monspecs.dclkmax ||
1445	info->monspecs.hfmax < info->monspecs.hfmin ||
1446	info->monspecs.vfmax < info->monspecs.vfmin ||
1447	info->monspecs.dclkmax < info->monspecs.dclkmin) {
1448	hfmin = 29000; hfmax = 30000;
1449	vfmin = 60; vfmax = 60;
1450	dclkmin = 0; dclkmax = 25000000;
1451	} else {
1452	hfmin = info->monspecs.hfmin;
1453	hfmax = info->monspecs.hfmax;
1454	vfmin = info->monspecs.vfmin;
1455	vfmax = info->monspecs.vfmax;
1456	dclkmin = info->monspecs.dclkmin;
1457	dclkmax = info->monspecs.dclkmax;
1458	}
1459
1460	if (!var->pixclock)
1461	return -EINVAL;
1462	pixclock = PICOS2KHZ(var->pixclock) * 1000;
1463
1464	htotal = var->xres + var->right_margin + var->hsync_len +
1465	var->left_margin;
1466	vtotal = var->yres + var->lower_margin + var->vsync_len +
1467	var->upper_margin;
1468
1469	if (var->vmode & FB_VMODE_INTERLACED)
1470	vtotal /= 2;
1471	if (var->vmode & FB_VMODE_DOUBLE)
1472	vtotal *= 2;
1473
1474	hfreq = pixclock/htotal;
1475	hfreq = (hfreq + 500) / 1000 * 1000;
1476
1477	vfreq = hfreq/vtotal;
1478
1479	return (vfreq < vfmin || vfreq > vfmax ||
1480	hfreq < hfmin || hfreq > hfmax ||
1481	pixclock < dclkmin || pixclock > dclkmax) ?
1482	-EINVAL : 0;
1483	}
1484
1485	#if defined(CONFIG_FIRMWARE_EDID) && defined(CONFIG_X86)
1486
1487	/*
1488	* We need to ensure that the EDID block is only returned for
1489	* the primary graphics adapter.
1490	*/
1491
1492	const unsigned char *fb_firmware_edid(struct device *device)
1493	{
1494	struct pci_dev *dev = NULL;
1495	struct resource *res = NULL;
1496	unsigned char *edid = NULL;
1497
1498	if (device)
1499	dev = to_pci_dev(device);
1500
1501	if (dev)
1502	res = &dev->resource[PCI_ROM_RESOURCE];
1503
1504	if (res && res->flags & IORESOURCE_ROM_SHADOW)
1505	edid = edid_info.dummy;
1506
1507	return edid;
1508	}
1509	#else
1510	const unsigned char *fb_firmware_edid(struct device *device)
1511	{
1512	return NULL;
1513	}
1514	#endif
1515	EXPORT_SYMBOL(fb_firmware_edid);
1516
1517	EXPORT_SYMBOL(fb_parse_edid);
1518	EXPORT_SYMBOL(fb_edid_to_monspecs);
1519	EXPORT_SYMBOL(fb_get_mode);
1520	EXPORT_SYMBOL(fb_validate_mode);
1521	EXPORT_SYMBOL(fb_destroy_modedb);
1522