1/* $NetBSD: edid.c,v 1.18 2022/09/25 21:27:39 thorpej Exp $ */
2
3/*-
4 * Copyright (c) 2006 Itronix Inc.
5 * All rights reserved.
6 *
7 * Written by Garrett D'Amore for Itronix Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. The name of Itronix Inc. may not be used to endorse
18 *    or promote products derived from this software without specific
19 *    prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND ANY EXPRESS
22 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
25 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
31 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35__KERNEL_RCSID(0, "$NetBSD: edid.c,v 1.18 2022/09/25 21:27:39 thorpej Exp $");
36
37#ifdef _KERNEL
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/device.h>
41#include <sys/kernel.h>
42#else
43#include <stdlib.h>
44#include <inttypes.h>
45#include <string.h>
46#include <errno.h>
47#include <stdio.h>
48#endif
49
50#include <dev/videomode/videomode.h>
51#include <dev/videomode/ediddevs.h>
52#include <dev/videomode/edidreg.h>
53#include <dev/videomode/edidvar.h>
54#include <dev/videomode/vesagtf.h>
55
56#define	EDIDVERBOSE	1
57#define	DIVIDE(x,y)	(((x) + ((y) / 2)) / (y))
58
59/* These are reversed established timing order */
60static const char *_edid_modes[] =  {
61	"1280x1024x75",
62	"1024x768x75",
63	"1024x768x70",
64	"1024x768x60",
65	"1024x768x87i",
66	"832x624x74",	/* rounding error, 74.55 Hz aka "832x624x75" */
67	"800x600x75",
68	"800x600x72",
69	"800x600x60",
70	"800x600x56",
71	"640x480x75",
72	"640x480x72",
73	"640x480x67",
74	"640x480x60",
75	"720x400x87",	/* rounding error, 87.85 Hz aka "720x400x88" */
76	"720x400x70",
77};
78
79#ifdef	EDIDVERBOSE
80struct edid_vendor {
81	const char	*vendor;
82	const char	*name;
83};
84
85struct edid_product {
86	const char	*vendor;
87	uint16_t	product;
88	const char	*name;
89};
90
91#include <dev/videomode/ediddevs_data.h>
92#endif	/* EDIDVERBOSE */
93
94static const char *
95edid_findvendor(const char *vendor)
96{
97#ifdef	EDIDVERBOSE
98	int	n;
99
100	for (n = 0; n < edid_nvendors; n++)
101		if (memcmp(edid_vendors[n].vendor, vendor, 3) == 0)
102			return edid_vendors[n].name;
103#endif
104	return NULL;
105}
106
107static const char *
108edid_findproduct(const char *vendor, uint16_t product)
109{
110#ifdef	EDIDVERBOSE
111	int	n;
112
113	for (n = 0; n < edid_nproducts; n++)
114		if (edid_products[n].product == product &&
115		    memcmp(edid_products[n].vendor, vendor, 3) == 0)
116			return edid_products[n].name;
117#endif	/* EDIDVERBOSE */
118	return NULL;
119
120}
121
122static void
123edid_strchomp(char *ptr)
124{
125	for (;;) {
126		switch (*ptr) {
127		case '\0':
128			return;
129		case '\r':
130		case '\n':
131			*ptr = '\0';
132			return;
133		}
134		ptr++;
135	}
136}
137
138int
139edid_is_valid(uint8_t *d)
140{
141	int sum = 0, i;
142	uint8_t sig[8] = EDID_SIGNATURE;
143
144	if (memcmp(d, sig, 8) != 0)
145		return EINVAL;
146
147	for (i = 0; i < 128; i++)
148		sum += d[i];
149	if ((sum & 0xff) != 0)
150		return EINVAL;
151
152	return 0;
153}
154
155void
156edid_print(struct edid_info *edid)
157{
158	int	i;
159
160	if (edid == NULL)
161		return;
162	printf("Vendor: [%s] %s\n", edid->edid_vendor, edid->edid_vendorname);
163	printf("Product: [%04X] %s\n", edid->edid_product,
164	    edid->edid_productname);
165	printf("Serial number: %s\n", edid->edid_serial);
166	printf("Manufactured %d Week %d\n",
167	    edid->edid_year, edid->edid_week);
168	printf("EDID Version %d.%d\n", edid->edid_version,
169	    edid->edid_revision);
170	printf("EDID Comment: %s\n", edid->edid_comment);
171
172	printf("Video Input: %x\n", edid->edid_video_input);
173	if (edid->edid_video_input & EDID_VIDEO_INPUT_DIGITAL) {
174		printf("\tDigital");
175		if (edid->edid_video_input & EDID_VIDEO_INPUT_DFP1_COMPAT)
176			printf(" (DFP 1.x compatible)");
177		printf("\n");
178	} else {
179		printf("\tAnalog\n");
180		switch (EDID_VIDEO_INPUT_LEVEL(edid->edid_video_input)) {
181		case 0:
182			printf("\t-0.7, 0.3V\n");
183			break;
184		case 1:
185			printf("\t-0.714, 0.286V\n");
186			break;
187		case 2:
188			printf("\t-1.0, 0.4V\n");
189			break;
190		case 3:
191			printf("\t-0.7, 0.0V\n");
192			break;
193		}
194		if (edid->edid_video_input & EDID_VIDEO_INPUT_BLANK_TO_BLACK)
195			printf("\tBlank-to-black setup\n");
196		if (edid->edid_video_input & EDID_VIDEO_INPUT_SEPARATE_SYNCS)
197			printf("\tSeparate syncs\n");
198		if (edid->edid_video_input & EDID_VIDEO_INPUT_COMPOSITE_SYNC)
199			printf("\tComposite sync\n");
200		if (edid->edid_video_input & EDID_VIDEO_INPUT_SYNC_ON_GRN)
201			printf("\tSync on green\n");
202		if (edid->edid_video_input & EDID_VIDEO_INPUT_SERRATION)
203			printf("\tSerration vsync\n");
204	}
205
206	printf("Gamma: %d.%02d\n",
207	    edid->edid_gamma / 100, edid->edid_gamma % 100);
208
209	printf("Max Size: %d cm x %d cm\n",
210	    edid->edid_max_hsize, edid->edid_max_vsize);
211
212	printf("Features: %x\n", edid->edid_features);
213	if (edid->edid_features & EDID_FEATURES_STANDBY)
214		printf("\tDPMS standby\n");
215	if (edid->edid_features & EDID_FEATURES_SUSPEND)
216		printf("\tDPMS suspend\n");
217	if (edid->edid_features & EDID_FEATURES_ACTIVE_OFF)
218		printf("\tDPMS active-off\n");
219	switch (EDID_FEATURES_DISP_TYPE(edid->edid_features)) {
220	case EDID_FEATURES_DISP_TYPE_MONO:
221		printf("\tMonochrome\n");
222		break;
223	case EDID_FEATURES_DISP_TYPE_RGB:
224		printf("\tRGB\n");
225		break;
226	case EDID_FEATURES_DISP_TYPE_NON_RGB:
227		printf("\tMulticolor\n");
228		break;
229	case EDID_FEATURES_DISP_TYPE_UNDEFINED:
230		printf("\tUndefined monitor type\n");
231		break;
232	}
233	if (edid->edid_features & EDID_FEATURES_STD_COLOR)
234		printf("\tStandard color space\n");
235	if (edid->edid_features & EDID_FEATURES_PREFERRED_TIMING)
236		printf("\tPreferred timing\n");
237	if (edid->edid_features & EDID_FEATURES_DEFAULT_GTF)
238		printf("\tDefault GTF supported\n");
239
240	printf("Chroma Info:\n");
241	printf("\tRed X: 0.%03d\n", edid->edid_chroma.ec_redx);
242	printf("\tRed Y: 0.%03d\n", edid->edid_chroma.ec_redy);
243	printf("\tGrn X: 0.%03d\n", edid->edid_chroma.ec_greenx);
244	printf("\tGrn Y: 0.%03d\n", edid->edid_chroma.ec_greeny);
245	printf("\tBlu X: 0.%03d\n", edid->edid_chroma.ec_bluex);
246	printf("\tBlu Y: 0.%03d\n", edid->edid_chroma.ec_bluey);
247	printf("\tWht X: 0.%03d\n", edid->edid_chroma.ec_whitex);
248	printf("\tWht Y: 0.%03d\n", edid->edid_chroma.ec_whitey);
249
250	if (edid->edid_have_range) {
251		printf("Range:\n");
252		printf("\tHorizontal: %d - %d kHz\n",
253		    edid->edid_range.er_min_hfreq,
254		    edid->edid_range.er_max_hfreq);
255		printf("\tVertical: %d - %d Hz\n",
256		    edid->edid_range.er_min_vfreq,
257		    edid->edid_range.er_max_vfreq);
258		printf("\tMax Dot Clock: %d MHz\n",
259		    edid->edid_range.er_max_clock);
260		if (edid->edid_range.er_have_gtf2) {
261			printf("\tGTF2 hfreq: %d\n",
262			    edid->edid_range.er_gtf2_hfreq);
263			printf("\tGTF2 C: %d\n", edid->edid_range.er_gtf2_c);
264			printf("\tGTF2 M: %d\n", edid->edid_range.er_gtf2_m);
265			printf("\tGTF2 J: %d\n", edid->edid_range.er_gtf2_j);
266			printf("\tGTF2 K: %d\n", edid->edid_range.er_gtf2_k);
267		}
268	}
269	printf("Video modes:\n");
270	for (i = 0; i < edid->edid_nmodes; i++) {
271		printf("\t%dx%d @ %dHz",
272		    edid->edid_modes[i].hdisplay,
273		    edid->edid_modes[i].vdisplay,
274		    DIVIDE(DIVIDE(edid->edid_modes[i].dot_clock * 1000,
275		    edid->edid_modes[i].htotal), edid->edid_modes[i].vtotal));
276		printf(" (%d %d %d %d %d %d %d",
277		    edid->edid_modes[i].dot_clock,
278		    edid->edid_modes[i].hsync_start,
279		    edid->edid_modes[i].hsync_end,
280		    edid->edid_modes[i].htotal,
281		    edid->edid_modes[i].vsync_start,
282		    edid->edid_modes[i].vsync_end,
283		    edid->edid_modes[i].vtotal);
284		printf(" %s%sH %s%sV)\n",
285		    edid->edid_modes[i].flags & VID_PHSYNC ? "+" : "",
286		    edid->edid_modes[i].flags & VID_NHSYNC ? "-" : "",
287		    edid->edid_modes[i].flags & VID_PVSYNC ? "+" : "",
288		    edid->edid_modes[i].flags & VID_NVSYNC ? "-" : "");
289	}
290	if (edid->edid_preferred_mode)
291		printf("Preferred mode: %dx%d @ %dHz\n",
292		    edid->edid_preferred_mode->hdisplay,
293		    edid->edid_preferred_mode->vdisplay,
294		    DIVIDE(DIVIDE(edid->edid_preferred_mode->dot_clock * 1000,
295		    edid->edid_preferred_mode->htotal),
296		    edid->edid_preferred_mode->vtotal));
297
298	printf("Number of extension blocks: %d\n", edid->edid_ext_block_count);
299}
300
301static const struct videomode *
302edid_mode_lookup_list(const char *name)
303{
304	int	i;
305
306	for (i = 0; i < videomode_count; i++)
307		if (strcmp(name, videomode_list[i].name) == 0)
308			return &videomode_list[i];
309	return NULL;
310}
311
312static struct videomode *
313edid_search_mode(struct edid_info *edid, const struct videomode *mode)
314{
315	int	refresh, i;
316
317	refresh = DIVIDE(DIVIDE(mode->dot_clock * 1000,
318	    mode->htotal), mode->vtotal);
319	for (i = 0; i < edid->edid_nmodes; i++) {
320		if (mode->hdisplay == edid->edid_modes[i].hdisplay &&
321		    mode->vdisplay == edid->edid_modes[i].vdisplay &&
322		    refresh == DIVIDE(DIVIDE(
323		    edid->edid_modes[i].dot_clock * 1000,
324		    edid->edid_modes[i].htotal), edid->edid_modes[i].vtotal)) {
325			return &edid->edid_modes[i];
326		}
327	}
328	return NULL;
329}
330
331static int
332edid_std_timing(uint8_t *data, struct videomode *vmp)
333{
334	unsigned			x, y, f;
335	const struct videomode		*lookup;
336	char				name[80];
337
338	if ((data[0] == 1 && data[1] == 1) ||
339	    (data[0] == 0 && data[1] == 0) ||
340	    (data[0] == 0x20 && data[1] == 0x20))
341		return 0;
342
343	x = EDID_STD_TIMING_HRES(data);
344	switch (EDID_STD_TIMING_RATIO(data)) {
345	case EDID_STD_TIMING_RATIO_16_10:
346		y = x * 10 / 16;
347		break;
348	case EDID_STD_TIMING_RATIO_4_3:
349		y = x * 3 / 4;
350		break;
351	case EDID_STD_TIMING_RATIO_5_4:
352		y = x * 4 / 5;
353		break;
354	case EDID_STD_TIMING_RATIO_16_9:
355	default:
356		y = x * 9 / 16;
357		break;
358	}
359	f = EDID_STD_TIMING_VFREQ(data);
360
361	/* first try to lookup the mode as a DMT timing */
362	snprintf(name, sizeof(name), "%dx%dx%d", x, y, f);
363	if ((lookup = edid_mode_lookup_list(name)) != NULL) {
364		*vmp = *lookup;
365	} else {
366		/* failing that, calculate it using gtf */
367		/*
368		 * Hmm. I'm not using alternate GTF timings, which
369		 * could, in theory, be present.
370		 */
371		vesagtf_mode(x, y, f, vmp);
372	}
373	return 1;
374}
375
376static int
377edid_det_timing(uint8_t *data, struct videomode *vmp)
378{
379	unsigned	hactive, hblank, hsyncwid, hsyncoff;
380	unsigned	vactive, vblank, vsyncwid, vsyncoff;
381	uint8_t		flags;
382
383	flags = EDID_DET_TIMING_FLAGS(data);
384
385	/* we don't support stereo modes (for now) */
386	if (flags & (EDID_DET_TIMING_FLAG_STEREO |
387		EDID_DET_TIMING_FLAG_STEREO_MODE))
388		return 0;
389
390	vmp->dot_clock = EDID_DET_TIMING_DOT_CLOCK(data) / 1000;
391
392	hactive = EDID_DET_TIMING_HACTIVE(data);
393	hblank = EDID_DET_TIMING_HBLANK(data);
394	hsyncwid = EDID_DET_TIMING_HSYNC_WIDTH(data);
395	hsyncoff = EDID_DET_TIMING_HSYNC_OFFSET(data);
396
397	vactive = EDID_DET_TIMING_VACTIVE(data);
398	vblank = EDID_DET_TIMING_VBLANK(data);
399	vsyncwid = EDID_DET_TIMING_VSYNC_WIDTH(data);
400	vsyncoff = EDID_DET_TIMING_VSYNC_OFFSET(data);
401
402	/* Borders are contained within the blank areas. */
403
404	vmp->hdisplay = hactive;
405	vmp->htotal = hactive + hblank;
406	vmp->hsync_start = hactive + hsyncoff;
407	vmp->hsync_end = vmp->hsync_start + hsyncwid;
408
409	vmp->vdisplay = vactive;
410	vmp->vtotal = vactive + vblank;
411	vmp->vsync_start = vactive + vsyncoff;
412	vmp->vsync_end = vmp->vsync_start + vsyncwid;
413
414	vmp->flags = 0;
415
416	if (flags & EDID_DET_TIMING_FLAG_INTERLACE)
417		vmp->flags |= VID_INTERLACE;
418	if (flags & EDID_DET_TIMING_FLAG_HSYNC_POSITIVE)
419		vmp->flags |= VID_PHSYNC;
420	else
421		vmp->flags |= VID_NHSYNC;
422
423	if (flags & EDID_DET_TIMING_FLAG_VSYNC_POSITIVE)
424		vmp->flags |= VID_PVSYNC;
425	else
426		vmp->flags |= VID_NVSYNC;
427
428	return 1;
429}
430
431static void bump_preferred_mode(struct edid_info *edid, struct videomode *m)
432{
433	/*
434	 * XXX
435	 * Iiyama 4800 series monitors may have their native resolution in the
436	 * 2nd detailed timing descriptor instead of the 1st. Try to detect
437	 * that here and pick the native mode anyway.
438	 */
439	if (edid->edid_preferred_mode == NULL) {
440		edid->edid_preferred_mode = m;
441	} else if ((strncmp((char*)edid->edid_vendor, "IVM", 3) == 0) &&
442	           (edid->edid_product == 0x4800) &&
443	           (edid->edid_preferred_mode->dot_clock < m->dot_clock))
444		edid->edid_preferred_mode = m;
445}
446
447static void
448edid_block(struct edid_info *edid, uint8_t *data)
449{
450	int			i;
451	struct videomode	mode, *exist_mode;
452
453	if (EDID_BLOCK_IS_DET_TIMING(data)) {
454		if (!edid_det_timing(data, &mode))
455			return;
456		/* Does this mode already exist? */
457		exist_mode = edid_search_mode(edid, &mode);
458		if (exist_mode != NULL) {
459			*exist_mode = mode;
460			bump_preferred_mode(edid, exist_mode);
461		} else {
462			edid->edid_modes[edid->edid_nmodes] = mode;
463			bump_preferred_mode(edid,
464			    &edid->edid_modes[edid->edid_nmodes]);
465			edid->edid_nmodes++;
466		}
467		return;
468	}
469
470	switch (EDID_BLOCK_TYPE(data)) {
471	case EDID_DESC_BLOCK_TYPE_SERIAL:
472		memcpy(edid->edid_serial, data + EDID_DESC_ASCII_DATA_OFFSET,
473		    EDID_DESC_ASCII_DATA_LEN);
474		edid->edid_serial[sizeof(edid->edid_serial) - 1] = 0;
475		break;
476
477	case EDID_DESC_BLOCK_TYPE_ASCII:
478		memset(edid->edid_comment, 0, sizeof(edid->edid_comment));
479		memcpy(edid->edid_comment, data + EDID_DESC_ASCII_DATA_OFFSET,
480		    EDID_DESC_ASCII_DATA_LEN);
481		edid->edid_comment[sizeof(edid->edid_comment) - 1] = 0;
482		break;
483
484	case EDID_DESC_BLOCK_TYPE_RANGE:
485		edid->edid_have_range = 1;
486		edid->edid_range.er_min_vfreq =	EDID_DESC_RANGE_MIN_VFREQ(data);
487		edid->edid_range.er_max_vfreq =	EDID_DESC_RANGE_MAX_VFREQ(data);
488		edid->edid_range.er_min_hfreq =	EDID_DESC_RANGE_MIN_HFREQ(data);
489		edid->edid_range.er_max_hfreq =	EDID_DESC_RANGE_MAX_HFREQ(data);
490		edid->edid_range.er_max_clock = EDID_DESC_RANGE_MAX_CLOCK(data);
491		if (!EDID_DESC_RANGE_HAVE_GTF2(data))
492			break;
493		edid->edid_range.er_have_gtf2 = 1;
494		edid->edid_range.er_gtf2_hfreq =
495		    EDID_DESC_RANGE_GTF2_HFREQ(data);
496		edid->edid_range.er_gtf2_c = EDID_DESC_RANGE_GTF2_C(data);
497		edid->edid_range.er_gtf2_m = EDID_DESC_RANGE_GTF2_M(data);
498		edid->edid_range.er_gtf2_j = EDID_DESC_RANGE_GTF2_J(data);
499		edid->edid_range.er_gtf2_k = EDID_DESC_RANGE_GTF2_K(data);
500		break;
501
502	case EDID_DESC_BLOCK_TYPE_NAME:
503		/* copy the product name into place */
504		memcpy(edid->edid_productname,
505		    data + EDID_DESC_ASCII_DATA_OFFSET,
506		    EDID_DESC_ASCII_DATA_LEN);
507		break;
508
509	case EDID_DESC_BLOCK_TYPE_STD_TIMING:
510		data += EDID_DESC_STD_TIMING_START;
511		for (i = 0; i < EDID_DESC_STD_TIMING_COUNT; i++) {
512			if (edid_std_timing(data, &mode)) {
513				/* Does this mode already exist? */
514				exist_mode = edid_search_mode(edid, &mode);
515				if (exist_mode == NULL) {
516					edid->edid_modes[edid->edid_nmodes] =
517					    mode;
518					edid->edid_nmodes++;
519				}
520			}
521			data += 2;
522		}
523		break;
524
525	case EDID_DESC_BLOCK_TYPE_COLOR_POINT:
526		/* XXX: not implemented yet */
527		break;
528	}
529}
530
531/*
532 * Gets EDID version in BCD, e.g. EDID v1.3  returned as 0x0103
533 */
534int
535edid_parse(uint8_t *data, struct edid_info *edid)
536{
537	uint16_t		manfid, estmodes;
538	const struct videomode	*vmp;
539	int			i;
540	const char		*name;
541	int max_dotclock = 0;
542	int mhz;
543
544	if (edid_is_valid(data) != 0)
545		return -1;
546
547	/* get product identification */
548	manfid = EDID_VENDOR_ID(data);
549	edid->edid_vendor[0] = EDID_MANFID_0(manfid);
550	edid->edid_vendor[1] = EDID_MANFID_1(manfid);
551	edid->edid_vendor[2] = EDID_MANFID_2(manfid);
552	edid->edid_vendor[3] = 0;	/* null terminate for convenience */
553
554	edid->edid_product = data[EDID_OFFSET_PRODUCT_ID] +
555	    (data[EDID_OFFSET_PRODUCT_ID + 1] << 8);
556
557	name = edid_findvendor((char *)edid->edid_vendor);
558	if (name != NULL)
559		strlcpy(edid->edid_vendorname, name,
560		    sizeof(edid->edid_vendorname));
561	else
562		edid->edid_vendorname[0] = '\0';
563
564	name = edid_findproduct((char *)edid->edid_vendor, edid->edid_product);
565	if (name != NULL)
566		strlcpy(edid->edid_productname, name,
567		    sizeof(edid->edid_productname));
568	else
569	    edid->edid_productname[0] = '\0';
570
571	snprintf(edid->edid_serial, sizeof(edid->edid_serial), "%08x",
572	    EDID_SERIAL_NUMBER(data));
573
574	edid->edid_comment[0] = '\0';
575
576	edid->edid_week = EDID_WEEK(data);
577	edid->edid_year = EDID_YEAR(data);
578
579	/* get edid revision */
580	edid->edid_version = EDID_VERSION(data);
581	edid->edid_revision = EDID_REVISION(data);
582
583	edid->edid_video_input = EDID_VIDEO_INPUT(data);
584	edid->edid_max_hsize = EDID_MAX_HSIZE(data);
585	edid->edid_max_vsize = EDID_MAX_VSIZE(data);
586
587	edid->edid_gamma = EDID_GAMMA(data);
588	edid->edid_features = EDID_FEATURES(data);
589
590	edid->edid_chroma.ec_redx = EDID_CHROMA_REDX(data);
591	edid->edid_chroma.ec_redy = EDID_CHROMA_REDX(data);
592	edid->edid_chroma.ec_greenx = EDID_CHROMA_GREENX(data);
593	edid->edid_chroma.ec_greeny = EDID_CHROMA_GREENY(data);
594	edid->edid_chroma.ec_bluex = EDID_CHROMA_BLUEX(data);
595	edid->edid_chroma.ec_bluey = EDID_CHROMA_BLUEY(data);
596	edid->edid_chroma.ec_whitex = EDID_CHROMA_WHITEX(data);
597	edid->edid_chroma.ec_whitey = EDID_CHROMA_WHITEY(data);
598
599	edid->edid_ext_block_count = EDID_EXT_BLOCK_COUNT(data);
600
601	/* lookup established modes */
602	edid->edid_nmodes = 0;
603	edid->edid_preferred_mode = NULL;
604	estmodes = EDID_EST_TIMING(data);
605	/* Iterate in esztablished timing order */
606	for (i = 15; i >= 0; i--) {
607		if (estmodes & (1 << i)) {
608			vmp = edid_mode_lookup_list(_edid_modes[i]);
609			if (vmp != NULL) {
610				edid->edid_modes[edid->edid_nmodes] = *vmp;
611				edid->edid_nmodes++;
612			}
613#ifdef DIAGNOSTIC
614			  else
615				printf("no data for est. mode %s\n",
616				    _edid_modes[i]);
617#endif
618		}
619	}
620
621	/* do standard timing section */
622	for (i = 0; i < EDID_STD_TIMING_COUNT; i++) {
623		struct videomode	mode, *exist_mode;
624		if (edid_std_timing(data + EDID_OFFSET_STD_TIMING + i * 2,
625			&mode)) {
626			/* Does this mode already exist? */
627			exist_mode = edid_search_mode(edid, &mode);
628			if (exist_mode == NULL) {
629				edid->edid_modes[edid->edid_nmodes] = mode;
630				edid->edid_nmodes++;
631			}
632		}
633	}
634
635	/* do detailed timings and descriptors */
636	for (i = 0; i < EDID_BLOCK_COUNT; i++) {
637		edid_block(edid, data + EDID_OFFSET_DESC_BLOCK +
638		    i * EDID_BLOCK_SIZE);
639	}
640
641	edid_strchomp(edid->edid_vendorname);
642	edid_strchomp(edid->edid_productname);
643	edid_strchomp(edid->edid_serial);
644	edid_strchomp(edid->edid_comment);
645
646	/*
647	 * XXX
648	 * some monitors lie about their maximum supported dot clock
649	 * by claiming to support modes which need a higher dot clock
650	 * than the stated maximum.
651	 * For sanity's sake we bump it to the highest dot clock we find
652	 * in the list of supported modes
653	 */
654	for (i = 0; i < edid->edid_nmodes; i++)
655		if (edid->edid_modes[i].dot_clock > max_dotclock)
656			max_dotclock = edid->edid_modes[i].dot_clock;
657
658#ifdef _KERNEL
659	aprint_debug("max_dotclock according to supported modes: %d\n",
660	    max_dotclock);
661#endif
662
663	mhz = (max_dotclock + 999) / 1000;
664
665	if (edid->edid_have_range) {
666		if (mhz > edid->edid_range.er_max_clock)
667			edid->edid_range.er_max_clock = mhz;
668	} else
669		edid->edid_range.er_max_clock = mhz;
670
671	return 0;
672}
673
674