xref: /openbmc/linux/drivers/gpu/drm/drm_edid.c (revision 8497f696)
1 /*
2  * Copyright (c) 2006 Luc Verhaegen (quirks list)
3  * Copyright (c) 2007-2008 Intel Corporation
4  *   Jesse Barnes <jesse.barnes@intel.com>
5  * Copyright 2010 Red Hat, Inc.
6  *
7  * DDC probing routines (drm_ddc_read & drm_do_probe_ddc_edid) originally from
8  * FB layer.
9  *   Copyright (C) 2006 Dennis Munsie <dmunsie@cecropia.com>
10  *
11  * Permission is hereby granted, free of charge, to any person obtaining a
12  * copy of this software and associated documentation files (the "Software"),
13  * to deal in the Software without restriction, including without limitation
14  * the rights to use, copy, modify, merge, publish, distribute, sub license,
15  * and/or sell copies of the Software, and to permit persons to whom the
16  * Software is furnished to do so, subject to the following conditions:
17  *
18  * The above copyright notice and this permission notice (including the
19  * next paragraph) shall be included in all copies or substantial portions
20  * of the Software.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
25  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
26  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
27  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
28  * DEALINGS IN THE SOFTWARE.
29  */
30 #include <linux/kernel.h>
31 #include <linux/slab.h>
32 #include <linux/i2c.h>
33 #include <linux/module.h>
34 #include "drmP.h"
35 #include "drm_edid.h"
36 #include "drm_edid_modes.h"
37 
38 #define version_greater(edid, maj, min) \
39 	(((edid)->version > (maj)) || \
40 	 ((edid)->version == (maj) && (edid)->revision > (min)))
41 
42 #define EDID_EST_TIMINGS 16
43 #define EDID_STD_TIMINGS 8
44 #define EDID_DETAILED_TIMINGS 4
45 
46 /*
47  * EDID blocks out in the wild have a variety of bugs, try to collect
48  * them here (note that userspace may work around broken monitors first,
49  * but fixes should make their way here so that the kernel "just works"
50  * on as many displays as possible).
51  */
52 
53 /* First detailed mode wrong, use largest 60Hz mode */
54 #define EDID_QUIRK_PREFER_LARGE_60		(1 << 0)
55 /* Reported 135MHz pixel clock is too high, needs adjustment */
56 #define EDID_QUIRK_135_CLOCK_TOO_HIGH		(1 << 1)
57 /* Prefer the largest mode at 75 Hz */
58 #define EDID_QUIRK_PREFER_LARGE_75		(1 << 2)
59 /* Detail timing is in cm not mm */
60 #define EDID_QUIRK_DETAILED_IN_CM		(1 << 3)
61 /* Detailed timing descriptors have bogus size values, so just take the
62  * maximum size and use that.
63  */
64 #define EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE	(1 << 4)
65 /* Monitor forgot to set the first detailed is preferred bit. */
66 #define EDID_QUIRK_FIRST_DETAILED_PREFERRED	(1 << 5)
67 /* use +hsync +vsync for detailed mode */
68 #define EDID_QUIRK_DETAILED_SYNC_PP		(1 << 6)
69 /* Force reduced-blanking timings for detailed modes */
70 #define EDID_QUIRK_FORCE_REDUCED_BLANKING	(1 << 7)
71 
72 struct detailed_mode_closure {
73 	struct drm_connector *connector;
74 	struct edid *edid;
75 	bool preferred;
76 	u32 quirks;
77 	int modes;
78 };
79 
80 #define LEVEL_DMT	0
81 #define LEVEL_GTF	1
82 #define LEVEL_GTF2	2
83 #define LEVEL_CVT	3
84 
85 static struct edid_quirk {
86 	char vendor[4];
87 	int product_id;
88 	u32 quirks;
89 } edid_quirk_list[] = {
90 	/* Acer AL1706 */
91 	{ "ACR", 44358, EDID_QUIRK_PREFER_LARGE_60 },
92 	/* Acer F51 */
93 	{ "API", 0x7602, EDID_QUIRK_PREFER_LARGE_60 },
94 	/* Unknown Acer */
95 	{ "ACR", 2423, EDID_QUIRK_FIRST_DETAILED_PREFERRED },
96 
97 	/* Belinea 10 15 55 */
98 	{ "MAX", 1516, EDID_QUIRK_PREFER_LARGE_60 },
99 	{ "MAX", 0x77e, EDID_QUIRK_PREFER_LARGE_60 },
100 
101 	/* Envision Peripherals, Inc. EN-7100e */
102 	{ "EPI", 59264, EDID_QUIRK_135_CLOCK_TOO_HIGH },
103 	/* Envision EN2028 */
104 	{ "EPI", 8232, EDID_QUIRK_PREFER_LARGE_60 },
105 
106 	/* Funai Electronics PM36B */
107 	{ "FCM", 13600, EDID_QUIRK_PREFER_LARGE_75 |
108 	  EDID_QUIRK_DETAILED_IN_CM },
109 
110 	/* LG Philips LCD LP154W01-A5 */
111 	{ "LPL", 0, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE },
112 	{ "LPL", 0x2a00, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE },
113 
114 	/* Philips 107p5 CRT */
115 	{ "PHL", 57364, EDID_QUIRK_FIRST_DETAILED_PREFERRED },
116 
117 	/* Proview AY765C */
118 	{ "PTS", 765, EDID_QUIRK_FIRST_DETAILED_PREFERRED },
119 
120 	/* Samsung SyncMaster 205BW.  Note: irony */
121 	{ "SAM", 541, EDID_QUIRK_DETAILED_SYNC_PP },
122 	/* Samsung SyncMaster 22[5-6]BW */
123 	{ "SAM", 596, EDID_QUIRK_PREFER_LARGE_60 },
124 	{ "SAM", 638, EDID_QUIRK_PREFER_LARGE_60 },
125 
126 	/* ViewSonic VA2026w */
127 	{ "VSC", 5020, EDID_QUIRK_FORCE_REDUCED_BLANKING },
128 };
129 
130 /*** DDC fetch and block validation ***/
131 
132 static const u8 edid_header[] = {
133 	0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00
134 };
135 
136  /*
137  * Sanity check the header of the base EDID block.  Return 8 if the header
138  * is perfect, down to 0 if it's totally wrong.
139  */
140 int drm_edid_header_is_valid(const u8 *raw_edid)
141 {
142 	int i, score = 0;
143 
144 	for (i = 0; i < sizeof(edid_header); i++)
145 		if (raw_edid[i] == edid_header[i])
146 			score++;
147 
148 	return score;
149 }
150 EXPORT_SYMBOL(drm_edid_header_is_valid);
151 
152 static int edid_fixup __read_mostly = 6;
153 module_param_named(edid_fixup, edid_fixup, int, 0400);
154 MODULE_PARM_DESC(edid_fixup,
155 		 "Minimum number of valid EDID header bytes (0-8, default 6)");
156 
157 /*
158  * Sanity check the EDID block (base or extension).  Return 0 if the block
159  * doesn't check out, or 1 if it's valid.
160  */
161 bool drm_edid_block_valid(u8 *raw_edid, int block)
162 {
163 	int i;
164 	u8 csum = 0;
165 	struct edid *edid = (struct edid *)raw_edid;
166 
167 	if (edid_fixup > 8 || edid_fixup < 0)
168 		edid_fixup = 6;
169 
170 	if (block == 0) {
171 		int score = drm_edid_header_is_valid(raw_edid);
172 		if (score == 8) ;
173 		else if (score >= edid_fixup) {
174 			DRM_DEBUG("Fixing EDID header, your hardware may be failing\n");
175 			memcpy(raw_edid, edid_header, sizeof(edid_header));
176 		} else {
177 			goto bad;
178 		}
179 	}
180 
181 	for (i = 0; i < EDID_LENGTH; i++)
182 		csum += raw_edid[i];
183 	if (csum) {
184 		DRM_ERROR("EDID checksum is invalid, remainder is %d\n", csum);
185 
186 		/* allow CEA to slide through, switches mangle this */
187 		if (raw_edid[0] != 0x02)
188 			goto bad;
189 	}
190 
191 	/* per-block-type checks */
192 	switch (raw_edid[0]) {
193 	case 0: /* base */
194 		if (edid->version != 1) {
195 			DRM_ERROR("EDID has major version %d, instead of 1\n", edid->version);
196 			goto bad;
197 		}
198 
199 		if (edid->revision > 4)
200 			DRM_DEBUG("EDID minor > 4, assuming backward compatibility\n");
201 		break;
202 
203 	default:
204 		break;
205 	}
206 
207 	return 1;
208 
209 bad:
210 	if (raw_edid) {
211 		printk(KERN_ERR "Raw EDID:\n");
212 		print_hex_dump(KERN_ERR, " \t", DUMP_PREFIX_NONE, 16, 1,
213 			       raw_edid, EDID_LENGTH, false);
214 	}
215 	return 0;
216 }
217 EXPORT_SYMBOL(drm_edid_block_valid);
218 
219 /**
220  * drm_edid_is_valid - sanity check EDID data
221  * @edid: EDID data
222  *
223  * Sanity-check an entire EDID record (including extensions)
224  */
225 bool drm_edid_is_valid(struct edid *edid)
226 {
227 	int i;
228 	u8 *raw = (u8 *)edid;
229 
230 	if (!edid)
231 		return false;
232 
233 	for (i = 0; i <= edid->extensions; i++)
234 		if (!drm_edid_block_valid(raw + i * EDID_LENGTH, i))
235 			return false;
236 
237 	return true;
238 }
239 EXPORT_SYMBOL(drm_edid_is_valid);
240 
241 #define DDC_SEGMENT_ADDR 0x30
242 /**
243  * Get EDID information via I2C.
244  *
245  * \param adapter : i2c device adaptor
246  * \param buf     : EDID data buffer to be filled
247  * \param len     : EDID data buffer length
248  * \return 0 on success or -1 on failure.
249  *
250  * Try to fetch EDID information by calling i2c driver function.
251  */
252 static int
253 drm_do_probe_ddc_edid(struct i2c_adapter *adapter, unsigned char *buf,
254 		      int block, int len)
255 {
256 	unsigned char start = block * EDID_LENGTH;
257 	int ret, retries = 5;
258 
259 	/* The core i2c driver will automatically retry the transfer if the
260 	 * adapter reports EAGAIN. However, we find that bit-banging transfers
261 	 * are susceptible to errors under a heavily loaded machine and
262 	 * generate spurious NAKs and timeouts. Retrying the transfer
263 	 * of the individual block a few times seems to overcome this.
264 	 */
265 	do {
266 		struct i2c_msg msgs[] = {
267 			{
268 				.addr	= DDC_ADDR,
269 				.flags	= 0,
270 				.len	= 1,
271 				.buf	= &start,
272 			}, {
273 				.addr	= DDC_ADDR,
274 				.flags	= I2C_M_RD,
275 				.len	= len,
276 				.buf	= buf,
277 			}
278 		};
279 		ret = i2c_transfer(adapter, msgs, 2);
280 		if (ret == -ENXIO) {
281 			DRM_DEBUG_KMS("drm: skipping non-existent adapter %s\n",
282 					adapter->name);
283 			break;
284 		}
285 	} while (ret != 2 && --retries);
286 
287 	return ret == 2 ? 0 : -1;
288 }
289 
290 static bool drm_edid_is_zero(u8 *in_edid, int length)
291 {
292 	int i;
293 	u32 *raw_edid = (u32 *)in_edid;
294 
295 	for (i = 0; i < length / 4; i++)
296 		if (*(raw_edid + i) != 0)
297 			return false;
298 	return true;
299 }
300 
301 static u8 *
302 drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter)
303 {
304 	int i, j = 0, valid_extensions = 0;
305 	u8 *block, *new;
306 
307 	if ((block = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL)
308 		return NULL;
309 
310 	/* base block fetch */
311 	for (i = 0; i < 4; i++) {
312 		if (drm_do_probe_ddc_edid(adapter, block, 0, EDID_LENGTH))
313 			goto out;
314 		if (drm_edid_block_valid(block, 0))
315 			break;
316 		if (i == 0 && drm_edid_is_zero(block, EDID_LENGTH)) {
317 			connector->null_edid_counter++;
318 			goto carp;
319 		}
320 	}
321 	if (i == 4)
322 		goto carp;
323 
324 	/* if there's no extensions, we're done */
325 	if (block[0x7e] == 0)
326 		return block;
327 
328 	new = krealloc(block, (block[0x7e] + 1) * EDID_LENGTH, GFP_KERNEL);
329 	if (!new)
330 		goto out;
331 	block = new;
332 
333 	for (j = 1; j <= block[0x7e]; j++) {
334 		for (i = 0; i < 4; i++) {
335 			if (drm_do_probe_ddc_edid(adapter,
336 				  block + (valid_extensions + 1) * EDID_LENGTH,
337 				  j, EDID_LENGTH))
338 				goto out;
339 			if (drm_edid_block_valid(block + (valid_extensions + 1) * EDID_LENGTH, j)) {
340 				valid_extensions++;
341 				break;
342 			}
343 		}
344 		if (i == 4)
345 			dev_warn(connector->dev->dev,
346 			 "%s: Ignoring invalid EDID block %d.\n",
347 			 drm_get_connector_name(connector), j);
348 	}
349 
350 	if (valid_extensions != block[0x7e]) {
351 		block[EDID_LENGTH-1] += block[0x7e] - valid_extensions;
352 		block[0x7e] = valid_extensions;
353 		new = krealloc(block, (valid_extensions + 1) * EDID_LENGTH, GFP_KERNEL);
354 		if (!new)
355 			goto out;
356 		block = new;
357 	}
358 
359 	return block;
360 
361 carp:
362 	dev_warn(connector->dev->dev, "%s: EDID block %d invalid.\n",
363 		 drm_get_connector_name(connector), j);
364 
365 out:
366 	kfree(block);
367 	return NULL;
368 }
369 
370 /**
371  * Probe DDC presence.
372  *
373  * \param adapter : i2c device adaptor
374  * \return 1 on success
375  */
376 static bool
377 drm_probe_ddc(struct i2c_adapter *adapter)
378 {
379 	unsigned char out;
380 
381 	return (drm_do_probe_ddc_edid(adapter, &out, 0, 1) == 0);
382 }
383 
384 /**
385  * drm_get_edid - get EDID data, if available
386  * @connector: connector we're probing
387  * @adapter: i2c adapter to use for DDC
388  *
389  * Poke the given i2c channel to grab EDID data if possible.  If found,
390  * attach it to the connector.
391  *
392  * Return edid data or NULL if we couldn't find any.
393  */
394 struct edid *drm_get_edid(struct drm_connector *connector,
395 			  struct i2c_adapter *adapter)
396 {
397 	struct edid *edid = NULL;
398 
399 	if (drm_probe_ddc(adapter))
400 		edid = (struct edid *)drm_do_get_edid(connector, adapter);
401 
402 	connector->display_info.raw_edid = (char *)edid;
403 
404 	return edid;
405 
406 }
407 EXPORT_SYMBOL(drm_get_edid);
408 
409 /*** EDID parsing ***/
410 
411 /**
412  * edid_vendor - match a string against EDID's obfuscated vendor field
413  * @edid: EDID to match
414  * @vendor: vendor string
415  *
416  * Returns true if @vendor is in @edid, false otherwise
417  */
418 static bool edid_vendor(struct edid *edid, char *vendor)
419 {
420 	char edid_vendor[3];
421 
422 	edid_vendor[0] = ((edid->mfg_id[0] & 0x7c) >> 2) + '@';
423 	edid_vendor[1] = (((edid->mfg_id[0] & 0x3) << 3) |
424 			  ((edid->mfg_id[1] & 0xe0) >> 5)) + '@';
425 	edid_vendor[2] = (edid->mfg_id[1] & 0x1f) + '@';
426 
427 	return !strncmp(edid_vendor, vendor, 3);
428 }
429 
430 /**
431  * edid_get_quirks - return quirk flags for a given EDID
432  * @edid: EDID to process
433  *
434  * This tells subsequent routines what fixes they need to apply.
435  */
436 static u32 edid_get_quirks(struct edid *edid)
437 {
438 	struct edid_quirk *quirk;
439 	int i;
440 
441 	for (i = 0; i < ARRAY_SIZE(edid_quirk_list); i++) {
442 		quirk = &edid_quirk_list[i];
443 
444 		if (edid_vendor(edid, quirk->vendor) &&
445 		    (EDID_PRODUCT_ID(edid) == quirk->product_id))
446 			return quirk->quirks;
447 	}
448 
449 	return 0;
450 }
451 
452 #define MODE_SIZE(m) ((m)->hdisplay * (m)->vdisplay)
453 #define MODE_REFRESH_DIFF(m,r) (abs((m)->vrefresh - target_refresh))
454 
455 /**
456  * edid_fixup_preferred - set preferred modes based on quirk list
457  * @connector: has mode list to fix up
458  * @quirks: quirks list
459  *
460  * Walk the mode list for @connector, clearing the preferred status
461  * on existing modes and setting it anew for the right mode ala @quirks.
462  */
463 static void edid_fixup_preferred(struct drm_connector *connector,
464 				 u32 quirks)
465 {
466 	struct drm_display_mode *t, *cur_mode, *preferred_mode;
467 	int target_refresh = 0;
468 
469 	if (list_empty(&connector->probed_modes))
470 		return;
471 
472 	if (quirks & EDID_QUIRK_PREFER_LARGE_60)
473 		target_refresh = 60;
474 	if (quirks & EDID_QUIRK_PREFER_LARGE_75)
475 		target_refresh = 75;
476 
477 	preferred_mode = list_first_entry(&connector->probed_modes,
478 					  struct drm_display_mode, head);
479 
480 	list_for_each_entry_safe(cur_mode, t, &connector->probed_modes, head) {
481 		cur_mode->type &= ~DRM_MODE_TYPE_PREFERRED;
482 
483 		if (cur_mode == preferred_mode)
484 			continue;
485 
486 		/* Largest mode is preferred */
487 		if (MODE_SIZE(cur_mode) > MODE_SIZE(preferred_mode))
488 			preferred_mode = cur_mode;
489 
490 		/* At a given size, try to get closest to target refresh */
491 		if ((MODE_SIZE(cur_mode) == MODE_SIZE(preferred_mode)) &&
492 		    MODE_REFRESH_DIFF(cur_mode, target_refresh) <
493 		    MODE_REFRESH_DIFF(preferred_mode, target_refresh)) {
494 			preferred_mode = cur_mode;
495 		}
496 	}
497 
498 	preferred_mode->type |= DRM_MODE_TYPE_PREFERRED;
499 }
500 
501 static bool
502 mode_is_rb(const struct drm_display_mode *mode)
503 {
504 	return (mode->htotal - mode->hdisplay == 160) &&
505 	       (mode->hsync_end - mode->hdisplay == 80) &&
506 	       (mode->hsync_end - mode->hsync_start == 32) &&
507 	       (mode->vsync_start - mode->vdisplay == 3);
508 }
509 
510 /*
511  * drm_mode_find_dmt - Create a copy of a mode if present in DMT
512  * @dev: Device to duplicate against
513  * @hsize: Mode width
514  * @vsize: Mode height
515  * @fresh: Mode refresh rate
516  * @rb: Mode reduced-blanking-ness
517  *
518  * Walk the DMT mode list looking for a match for the given parameters.
519  * Return a newly allocated copy of the mode, or NULL if not found.
520  */
521 struct drm_display_mode *drm_mode_find_dmt(struct drm_device *dev,
522 					   int hsize, int vsize, int fresh,
523 					   bool rb)
524 {
525 	int i;
526 
527 	for (i = 0; i < drm_num_dmt_modes; i++) {
528 		const struct drm_display_mode *ptr = &drm_dmt_modes[i];
529 		if (hsize != ptr->hdisplay)
530 			continue;
531 		if (vsize != ptr->vdisplay)
532 			continue;
533 		if (fresh != drm_mode_vrefresh(ptr))
534 			continue;
535 		if (rb != mode_is_rb(ptr))
536 			continue;
537 
538 		return drm_mode_duplicate(dev, ptr);
539 	}
540 
541 	return NULL;
542 }
543 EXPORT_SYMBOL(drm_mode_find_dmt);
544 
545 typedef void detailed_cb(struct detailed_timing *timing, void *closure);
546 
547 static void
548 cea_for_each_detailed_block(u8 *ext, detailed_cb *cb, void *closure)
549 {
550 	int i, n = 0;
551 	u8 d = ext[0x02];
552 	u8 *det_base = ext + d;
553 
554 	n = (127 - d) / 18;
555 	for (i = 0; i < n; i++)
556 		cb((struct detailed_timing *)(det_base + 18 * i), closure);
557 }
558 
559 static void
560 vtb_for_each_detailed_block(u8 *ext, detailed_cb *cb, void *closure)
561 {
562 	unsigned int i, n = min((int)ext[0x02], 6);
563 	u8 *det_base = ext + 5;
564 
565 	if (ext[0x01] != 1)
566 		return; /* unknown version */
567 
568 	for (i = 0; i < n; i++)
569 		cb((struct detailed_timing *)(det_base + 18 * i), closure);
570 }
571 
572 static void
573 drm_for_each_detailed_block(u8 *raw_edid, detailed_cb *cb, void *closure)
574 {
575 	int i;
576 	struct edid *edid = (struct edid *)raw_edid;
577 
578 	if (edid == NULL)
579 		return;
580 
581 	for (i = 0; i < EDID_DETAILED_TIMINGS; i++)
582 		cb(&(edid->detailed_timings[i]), closure);
583 
584 	for (i = 1; i <= raw_edid[0x7e]; i++) {
585 		u8 *ext = raw_edid + (i * EDID_LENGTH);
586 		switch (*ext) {
587 		case CEA_EXT:
588 			cea_for_each_detailed_block(ext, cb, closure);
589 			break;
590 		case VTB_EXT:
591 			vtb_for_each_detailed_block(ext, cb, closure);
592 			break;
593 		default:
594 			break;
595 		}
596 	}
597 }
598 
599 static void
600 is_rb(struct detailed_timing *t, void *data)
601 {
602 	u8 *r = (u8 *)t;
603 	if (r[3] == EDID_DETAIL_MONITOR_RANGE)
604 		if (r[15] & 0x10)
605 			*(bool *)data = true;
606 }
607 
608 /* EDID 1.4 defines this explicitly.  For EDID 1.3, we guess, badly. */
609 static bool
610 drm_monitor_supports_rb(struct edid *edid)
611 {
612 	if (edid->revision >= 4) {
613 		bool ret;
614 		drm_for_each_detailed_block((u8 *)edid, is_rb, &ret);
615 		return ret;
616 	}
617 
618 	return ((edid->input & DRM_EDID_INPUT_DIGITAL) != 0);
619 }
620 
621 static void
622 find_gtf2(struct detailed_timing *t, void *data)
623 {
624 	u8 *r = (u8 *)t;
625 	if (r[3] == EDID_DETAIL_MONITOR_RANGE && r[10] == 0x02)
626 		*(u8 **)data = r;
627 }
628 
629 /* Secondary GTF curve kicks in above some break frequency */
630 static int
631 drm_gtf2_hbreak(struct edid *edid)
632 {
633 	u8 *r = NULL;
634 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
635 	return r ? (r[12] * 2) : 0;
636 }
637 
638 static int
639 drm_gtf2_2c(struct edid *edid)
640 {
641 	u8 *r = NULL;
642 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
643 	return r ? r[13] : 0;
644 }
645 
646 static int
647 drm_gtf2_m(struct edid *edid)
648 {
649 	u8 *r = NULL;
650 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
651 	return r ? (r[15] << 8) + r[14] : 0;
652 }
653 
654 static int
655 drm_gtf2_k(struct edid *edid)
656 {
657 	u8 *r = NULL;
658 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
659 	return r ? r[16] : 0;
660 }
661 
662 static int
663 drm_gtf2_2j(struct edid *edid)
664 {
665 	u8 *r = NULL;
666 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
667 	return r ? r[17] : 0;
668 }
669 
670 /**
671  * standard_timing_level - get std. timing level(CVT/GTF/DMT)
672  * @edid: EDID block to scan
673  */
674 static int standard_timing_level(struct edid *edid)
675 {
676 	if (edid->revision >= 2) {
677 		if (edid->revision >= 4 && (edid->features & DRM_EDID_FEATURE_DEFAULT_GTF))
678 			return LEVEL_CVT;
679 		if (drm_gtf2_hbreak(edid))
680 			return LEVEL_GTF2;
681 		return LEVEL_GTF;
682 	}
683 	return LEVEL_DMT;
684 }
685 
686 /*
687  * 0 is reserved.  The spec says 0x01 fill for unused timings.  Some old
688  * monitors fill with ascii space (0x20) instead.
689  */
690 static int
691 bad_std_timing(u8 a, u8 b)
692 {
693 	return (a == 0x00 && b == 0x00) ||
694 	       (a == 0x01 && b == 0x01) ||
695 	       (a == 0x20 && b == 0x20);
696 }
697 
698 /**
699  * drm_mode_std - convert standard mode info (width, height, refresh) into mode
700  * @t: standard timing params
701  * @timing_level: standard timing level
702  *
703  * Take the standard timing params (in this case width, aspect, and refresh)
704  * and convert them into a real mode using CVT/GTF/DMT.
705  */
706 static struct drm_display_mode *
707 drm_mode_std(struct drm_connector *connector, struct edid *edid,
708 	     struct std_timing *t, int revision)
709 {
710 	struct drm_device *dev = connector->dev;
711 	struct drm_display_mode *m, *mode = NULL;
712 	int hsize, vsize;
713 	int vrefresh_rate;
714 	unsigned aspect_ratio = (t->vfreq_aspect & EDID_TIMING_ASPECT_MASK)
715 		>> EDID_TIMING_ASPECT_SHIFT;
716 	unsigned vfreq = (t->vfreq_aspect & EDID_TIMING_VFREQ_MASK)
717 		>> EDID_TIMING_VFREQ_SHIFT;
718 	int timing_level = standard_timing_level(edid);
719 
720 	if (bad_std_timing(t->hsize, t->vfreq_aspect))
721 		return NULL;
722 
723 	/* According to the EDID spec, the hdisplay = hsize * 8 + 248 */
724 	hsize = t->hsize * 8 + 248;
725 	/* vrefresh_rate = vfreq + 60 */
726 	vrefresh_rate = vfreq + 60;
727 	/* the vdisplay is calculated based on the aspect ratio */
728 	if (aspect_ratio == 0) {
729 		if (revision < 3)
730 			vsize = hsize;
731 		else
732 			vsize = (hsize * 10) / 16;
733 	} else if (aspect_ratio == 1)
734 		vsize = (hsize * 3) / 4;
735 	else if (aspect_ratio == 2)
736 		vsize = (hsize * 4) / 5;
737 	else
738 		vsize = (hsize * 9) / 16;
739 
740 	/* HDTV hack, part 1 */
741 	if (vrefresh_rate == 60 &&
742 	    ((hsize == 1360 && vsize == 765) ||
743 	     (hsize == 1368 && vsize == 769))) {
744 		hsize = 1366;
745 		vsize = 768;
746 	}
747 
748 	/*
749 	 * If this connector already has a mode for this size and refresh
750 	 * rate (because it came from detailed or CVT info), use that
751 	 * instead.  This way we don't have to guess at interlace or
752 	 * reduced blanking.
753 	 */
754 	list_for_each_entry(m, &connector->probed_modes, head)
755 		if (m->hdisplay == hsize && m->vdisplay == vsize &&
756 		    drm_mode_vrefresh(m) == vrefresh_rate)
757 			return NULL;
758 
759 	/* HDTV hack, part 2 */
760 	if (hsize == 1366 && vsize == 768 && vrefresh_rate == 60) {
761 		mode = drm_cvt_mode(dev, 1366, 768, vrefresh_rate, 0, 0,
762 				    false);
763 		mode->hdisplay = 1366;
764 		mode->hsync_start = mode->hsync_start - 1;
765 		mode->hsync_end = mode->hsync_end - 1;
766 		return mode;
767 	}
768 
769 	/* check whether it can be found in default mode table */
770 	if (drm_monitor_supports_rb(edid)) {
771 		mode = drm_mode_find_dmt(dev, hsize, vsize, vrefresh_rate,
772 					 true);
773 		if (mode)
774 			return mode;
775 	}
776 	mode = drm_mode_find_dmt(dev, hsize, vsize, vrefresh_rate, false);
777 	if (mode)
778 		return mode;
779 
780 	/* okay, generate it */
781 	switch (timing_level) {
782 	case LEVEL_DMT:
783 		break;
784 	case LEVEL_GTF:
785 		mode = drm_gtf_mode(dev, hsize, vsize, vrefresh_rate, 0, 0);
786 		break;
787 	case LEVEL_GTF2:
788 		/*
789 		 * This is potentially wrong if there's ever a monitor with
790 		 * more than one ranges section, each claiming a different
791 		 * secondary GTF curve.  Please don't do that.
792 		 */
793 		mode = drm_gtf_mode(dev, hsize, vsize, vrefresh_rate, 0, 0);
794 		if (!mode)
795 			return NULL;
796 		if (drm_mode_hsync(mode) > drm_gtf2_hbreak(edid)) {
797 			drm_mode_destroy(dev, mode);
798 			mode = drm_gtf_mode_complex(dev, hsize, vsize,
799 						    vrefresh_rate, 0, 0,
800 						    drm_gtf2_m(edid),
801 						    drm_gtf2_2c(edid),
802 						    drm_gtf2_k(edid),
803 						    drm_gtf2_2j(edid));
804 		}
805 		break;
806 	case LEVEL_CVT:
807 		mode = drm_cvt_mode(dev, hsize, vsize, vrefresh_rate, 0, 0,
808 				    false);
809 		break;
810 	}
811 	return mode;
812 }
813 
814 /*
815  * EDID is delightfully ambiguous about how interlaced modes are to be
816  * encoded.  Our internal representation is of frame height, but some
817  * HDTV detailed timings are encoded as field height.
818  *
819  * The format list here is from CEA, in frame size.  Technically we
820  * should be checking refresh rate too.  Whatever.
821  */
822 static void
823 drm_mode_do_interlace_quirk(struct drm_display_mode *mode,
824 			    struct detailed_pixel_timing *pt)
825 {
826 	int i;
827 	static const struct {
828 		int w, h;
829 	} cea_interlaced[] = {
830 		{ 1920, 1080 },
831 		{  720,  480 },
832 		{ 1440,  480 },
833 		{ 2880,  480 },
834 		{  720,  576 },
835 		{ 1440,  576 },
836 		{ 2880,  576 },
837 	};
838 
839 	if (!(pt->misc & DRM_EDID_PT_INTERLACED))
840 		return;
841 
842 	for (i = 0; i < ARRAY_SIZE(cea_interlaced); i++) {
843 		if ((mode->hdisplay == cea_interlaced[i].w) &&
844 		    (mode->vdisplay == cea_interlaced[i].h / 2)) {
845 			mode->vdisplay *= 2;
846 			mode->vsync_start *= 2;
847 			mode->vsync_end *= 2;
848 			mode->vtotal *= 2;
849 			mode->vtotal |= 1;
850 		}
851 	}
852 
853 	mode->flags |= DRM_MODE_FLAG_INTERLACE;
854 }
855 
856 /**
857  * drm_mode_detailed - create a new mode from an EDID detailed timing section
858  * @dev: DRM device (needed to create new mode)
859  * @edid: EDID block
860  * @timing: EDID detailed timing info
861  * @quirks: quirks to apply
862  *
863  * An EDID detailed timing block contains enough info for us to create and
864  * return a new struct drm_display_mode.
865  */
866 static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
867 						  struct edid *edid,
868 						  struct detailed_timing *timing,
869 						  u32 quirks)
870 {
871 	struct drm_display_mode *mode;
872 	struct detailed_pixel_timing *pt = &timing->data.pixel_data;
873 	unsigned hactive = (pt->hactive_hblank_hi & 0xf0) << 4 | pt->hactive_lo;
874 	unsigned vactive = (pt->vactive_vblank_hi & 0xf0) << 4 | pt->vactive_lo;
875 	unsigned hblank = (pt->hactive_hblank_hi & 0xf) << 8 | pt->hblank_lo;
876 	unsigned vblank = (pt->vactive_vblank_hi & 0xf) << 8 | pt->vblank_lo;
877 	unsigned hsync_offset = (pt->hsync_vsync_offset_pulse_width_hi & 0xc0) << 2 | pt->hsync_offset_lo;
878 	unsigned hsync_pulse_width = (pt->hsync_vsync_offset_pulse_width_hi & 0x30) << 4 | pt->hsync_pulse_width_lo;
879 	unsigned vsync_offset = (pt->hsync_vsync_offset_pulse_width_hi & 0xc) >> 2 | pt->vsync_offset_pulse_width_lo >> 4;
880 	unsigned vsync_pulse_width = (pt->hsync_vsync_offset_pulse_width_hi & 0x3) << 4 | (pt->vsync_offset_pulse_width_lo & 0xf);
881 
882 	/* ignore tiny modes */
883 	if (hactive < 64 || vactive < 64)
884 		return NULL;
885 
886 	if (pt->misc & DRM_EDID_PT_STEREO) {
887 		printk(KERN_WARNING "stereo mode not supported\n");
888 		return NULL;
889 	}
890 	if (!(pt->misc & DRM_EDID_PT_SEPARATE_SYNC)) {
891 		printk(KERN_WARNING "composite sync not supported\n");
892 	}
893 
894 	/* it is incorrect if hsync/vsync width is zero */
895 	if (!hsync_pulse_width || !vsync_pulse_width) {
896 		DRM_DEBUG_KMS("Incorrect Detailed timing. "
897 				"Wrong Hsync/Vsync pulse width\n");
898 		return NULL;
899 	}
900 
901 	if (quirks & EDID_QUIRK_FORCE_REDUCED_BLANKING) {
902 		mode = drm_cvt_mode(dev, hactive, vactive, 60, true, false, false);
903 		if (!mode)
904 			return NULL;
905 
906 		goto set_size;
907 	}
908 
909 	mode = drm_mode_create(dev);
910 	if (!mode)
911 		return NULL;
912 
913 	if (quirks & EDID_QUIRK_135_CLOCK_TOO_HIGH)
914 		timing->pixel_clock = cpu_to_le16(1088);
915 
916 	mode->clock = le16_to_cpu(timing->pixel_clock) * 10;
917 
918 	mode->hdisplay = hactive;
919 	mode->hsync_start = mode->hdisplay + hsync_offset;
920 	mode->hsync_end = mode->hsync_start + hsync_pulse_width;
921 	mode->htotal = mode->hdisplay + hblank;
922 
923 	mode->vdisplay = vactive;
924 	mode->vsync_start = mode->vdisplay + vsync_offset;
925 	mode->vsync_end = mode->vsync_start + vsync_pulse_width;
926 	mode->vtotal = mode->vdisplay + vblank;
927 
928 	/* Some EDIDs have bogus h/vtotal values */
929 	if (mode->hsync_end > mode->htotal)
930 		mode->htotal = mode->hsync_end + 1;
931 	if (mode->vsync_end > mode->vtotal)
932 		mode->vtotal = mode->vsync_end + 1;
933 
934 	drm_mode_do_interlace_quirk(mode, pt);
935 
936 	if (quirks & EDID_QUIRK_DETAILED_SYNC_PP) {
937 		pt->misc |= DRM_EDID_PT_HSYNC_POSITIVE | DRM_EDID_PT_VSYNC_POSITIVE;
938 	}
939 
940 	mode->flags |= (pt->misc & DRM_EDID_PT_HSYNC_POSITIVE) ?
941 		DRM_MODE_FLAG_PHSYNC : DRM_MODE_FLAG_NHSYNC;
942 	mode->flags |= (pt->misc & DRM_EDID_PT_VSYNC_POSITIVE) ?
943 		DRM_MODE_FLAG_PVSYNC : DRM_MODE_FLAG_NVSYNC;
944 
945 set_size:
946 	mode->width_mm = pt->width_mm_lo | (pt->width_height_mm_hi & 0xf0) << 4;
947 	mode->height_mm = pt->height_mm_lo | (pt->width_height_mm_hi & 0xf) << 8;
948 
949 	if (quirks & EDID_QUIRK_DETAILED_IN_CM) {
950 		mode->width_mm *= 10;
951 		mode->height_mm *= 10;
952 	}
953 
954 	if (quirks & EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE) {
955 		mode->width_mm = edid->width_cm * 10;
956 		mode->height_mm = edid->height_cm * 10;
957 	}
958 
959 	mode->type = DRM_MODE_TYPE_DRIVER;
960 	drm_mode_set_name(mode);
961 
962 	return mode;
963 }
964 
965 static bool
966 mode_in_hsync_range(const struct drm_display_mode *mode,
967 		    struct edid *edid, u8 *t)
968 {
969 	int hsync, hmin, hmax;
970 
971 	hmin = t[7];
972 	if (edid->revision >= 4)
973 	    hmin += ((t[4] & 0x04) ? 255 : 0);
974 	hmax = t[8];
975 	if (edid->revision >= 4)
976 	    hmax += ((t[4] & 0x08) ? 255 : 0);
977 	hsync = drm_mode_hsync(mode);
978 
979 	return (hsync <= hmax && hsync >= hmin);
980 }
981 
982 static bool
983 mode_in_vsync_range(const struct drm_display_mode *mode,
984 		    struct edid *edid, u8 *t)
985 {
986 	int vsync, vmin, vmax;
987 
988 	vmin = t[5];
989 	if (edid->revision >= 4)
990 	    vmin += ((t[4] & 0x01) ? 255 : 0);
991 	vmax = t[6];
992 	if (edid->revision >= 4)
993 	    vmax += ((t[4] & 0x02) ? 255 : 0);
994 	vsync = drm_mode_vrefresh(mode);
995 
996 	return (vsync <= vmax && vsync >= vmin);
997 }
998 
999 static u32
1000 range_pixel_clock(struct edid *edid, u8 *t)
1001 {
1002 	/* unspecified */
1003 	if (t[9] == 0 || t[9] == 255)
1004 		return 0;
1005 
1006 	/* 1.4 with CVT support gives us real precision, yay */
1007 	if (edid->revision >= 4 && t[10] == 0x04)
1008 		return (t[9] * 10000) - ((t[12] >> 2) * 250);
1009 
1010 	/* 1.3 is pathetic, so fuzz up a bit */
1011 	return t[9] * 10000 + 5001;
1012 }
1013 
1014 static bool
1015 mode_in_range(const struct drm_display_mode *mode, struct edid *edid,
1016 	      struct detailed_timing *timing)
1017 {
1018 	u32 max_clock;
1019 	u8 *t = (u8 *)timing;
1020 
1021 	if (!mode_in_hsync_range(mode, edid, t))
1022 		return false;
1023 
1024 	if (!mode_in_vsync_range(mode, edid, t))
1025 		return false;
1026 
1027 	if ((max_clock = range_pixel_clock(edid, t)))
1028 		if (mode->clock > max_clock)
1029 			return false;
1030 
1031 	/* 1.4 max horizontal check */
1032 	if (edid->revision >= 4 && t[10] == 0x04)
1033 		if (t[13] && mode->hdisplay > 8 * (t[13] + (256 * (t[12]&0x3))))
1034 			return false;
1035 
1036 	if (mode_is_rb(mode) && !drm_monitor_supports_rb(edid))
1037 		return false;
1038 
1039 	return true;
1040 }
1041 
1042 static int
1043 drm_dmt_modes_for_range(struct drm_connector *connector, struct edid *edid,
1044 			struct detailed_timing *timing)
1045 {
1046 	int i, modes = 0;
1047 	struct drm_display_mode *newmode;
1048 	struct drm_device *dev = connector->dev;
1049 
1050 	for (i = 0; i < drm_num_dmt_modes; i++) {
1051 		if (mode_in_range(drm_dmt_modes + i, edid, timing)) {
1052 			newmode = drm_mode_duplicate(dev, &drm_dmt_modes[i]);
1053 			if (newmode) {
1054 				drm_mode_probed_add(connector, newmode);
1055 				modes++;
1056 			}
1057 		}
1058 	}
1059 
1060 	return modes;
1061 }
1062 
1063 /* fix up 1366x768 mode from 1368x768;
1064  * GFT/CVT can't express 1366 width which isn't dividable by 8
1065  */
1066 static void fixup_mode_1366x768(struct drm_display_mode *mode)
1067 {
1068 	if (mode->hdisplay == 1368 && mode->vdisplay == 768) {
1069 		mode->hdisplay = 1366;
1070 		mode->hsync_start--;
1071 		mode->hsync_end--;
1072 		drm_mode_set_name(mode);
1073 	}
1074 }
1075 
1076 static int
1077 drm_gtf_modes_for_range(struct drm_connector *connector, struct edid *edid,
1078 			struct detailed_timing *timing)
1079 {
1080 	int i, modes = 0;
1081 	struct drm_display_mode *newmode;
1082 	struct drm_device *dev = connector->dev;
1083 
1084 	for (i = 0; i < num_extra_modes; i++) {
1085 		const struct minimode *m = &extra_modes[i];
1086 		newmode = drm_gtf_mode(dev, m->w, m->h, m->r, 0, 0);
1087 		if (!newmode)
1088 			return modes;
1089 
1090 		fixup_mode_1366x768(newmode);
1091 		if (!mode_in_range(newmode, edid, timing)) {
1092 			drm_mode_destroy(dev, newmode);
1093 			continue;
1094 		}
1095 
1096 		drm_mode_probed_add(connector, newmode);
1097 		modes++;
1098 	}
1099 
1100 	return modes;
1101 }
1102 
1103 static int
1104 drm_cvt_modes_for_range(struct drm_connector *connector, struct edid *edid,
1105 			struct detailed_timing *timing)
1106 {
1107 	int i, modes = 0;
1108 	struct drm_display_mode *newmode;
1109 	struct drm_device *dev = connector->dev;
1110 	bool rb = drm_monitor_supports_rb(edid);
1111 
1112 	for (i = 0; i < num_extra_modes; i++) {
1113 		const struct minimode *m = &extra_modes[i];
1114 		newmode = drm_cvt_mode(dev, m->w, m->h, m->r, rb, 0, 0);
1115 		if (!newmode)
1116 			return modes;
1117 
1118 		fixup_mode_1366x768(newmode);
1119 		if (!mode_in_range(newmode, edid, timing)) {
1120 			drm_mode_destroy(dev, newmode);
1121 			continue;
1122 		}
1123 
1124 		drm_mode_probed_add(connector, newmode);
1125 		modes++;
1126 	}
1127 
1128 	return modes;
1129 }
1130 
1131 static void
1132 do_inferred_modes(struct detailed_timing *timing, void *c)
1133 {
1134 	struct detailed_mode_closure *closure = c;
1135 	struct detailed_non_pixel *data = &timing->data.other_data;
1136 	struct detailed_data_monitor_range *range = &data->data.range;
1137 
1138 	if (data->type != EDID_DETAIL_MONITOR_RANGE)
1139 		return;
1140 
1141 	closure->modes += drm_dmt_modes_for_range(closure->connector,
1142 						  closure->edid,
1143 						  timing);
1144 
1145 	if (!version_greater(closure->edid, 1, 1))
1146 		return; /* GTF not defined yet */
1147 
1148 	switch (range->flags) {
1149 	case 0x02: /* secondary gtf, XXX could do more */
1150 	case 0x00: /* default gtf */
1151 		closure->modes += drm_gtf_modes_for_range(closure->connector,
1152 							  closure->edid,
1153 							  timing);
1154 		break;
1155 	case 0x04: /* cvt, only in 1.4+ */
1156 		if (!version_greater(closure->edid, 1, 3))
1157 			break;
1158 
1159 		closure->modes += drm_cvt_modes_for_range(closure->connector,
1160 							  closure->edid,
1161 							  timing);
1162 		break;
1163 	case 0x01: /* just the ranges, no formula */
1164 	default:
1165 		break;
1166 	}
1167 }
1168 
1169 static int
1170 add_inferred_modes(struct drm_connector *connector, struct edid *edid)
1171 {
1172 	struct detailed_mode_closure closure = {
1173 		connector, edid, 0, 0, 0
1174 	};
1175 
1176 	if (version_greater(edid, 1, 0))
1177 		drm_for_each_detailed_block((u8 *)edid, do_inferred_modes,
1178 					    &closure);
1179 
1180 	return closure.modes;
1181 }
1182 
1183 static int
1184 drm_est3_modes(struct drm_connector *connector, struct detailed_timing *timing)
1185 {
1186 	int i, j, m, modes = 0;
1187 	struct drm_display_mode *mode;
1188 	u8 *est = ((u8 *)timing) + 5;
1189 
1190 	for (i = 0; i < 6; i++) {
1191 		for (j = 7; j > 0; j--) {
1192 			m = (i * 8) + (7 - j);
1193 			if (m >= ARRAY_SIZE(est3_modes))
1194 				break;
1195 			if (est[i] & (1 << j)) {
1196 				mode = drm_mode_find_dmt(connector->dev,
1197 							 est3_modes[m].w,
1198 							 est3_modes[m].h,
1199 							 est3_modes[m].r,
1200 							 est3_modes[m].rb);
1201 				if (mode) {
1202 					drm_mode_probed_add(connector, mode);
1203 					modes++;
1204 				}
1205 			}
1206 		}
1207 	}
1208 
1209 	return modes;
1210 }
1211 
1212 static void
1213 do_established_modes(struct detailed_timing *timing, void *c)
1214 {
1215 	struct detailed_mode_closure *closure = c;
1216 	struct detailed_non_pixel *data = &timing->data.other_data;
1217 
1218 	if (data->type == EDID_DETAIL_EST_TIMINGS)
1219 		closure->modes += drm_est3_modes(closure->connector, timing);
1220 }
1221 
1222 /**
1223  * add_established_modes - get est. modes from EDID and add them
1224  * @edid: EDID block to scan
1225  *
1226  * Each EDID block contains a bitmap of the supported "established modes" list
1227  * (defined above).  Tease them out and add them to the global modes list.
1228  */
1229 static int
1230 add_established_modes(struct drm_connector *connector, struct edid *edid)
1231 {
1232 	struct drm_device *dev = connector->dev;
1233 	unsigned long est_bits = edid->established_timings.t1 |
1234 		(edid->established_timings.t2 << 8) |
1235 		((edid->established_timings.mfg_rsvd & 0x80) << 9);
1236 	int i, modes = 0;
1237 	struct detailed_mode_closure closure = {
1238 		connector, edid, 0, 0, 0
1239 	};
1240 
1241 	for (i = 0; i <= EDID_EST_TIMINGS; i++) {
1242 		if (est_bits & (1<<i)) {
1243 			struct drm_display_mode *newmode;
1244 			newmode = drm_mode_duplicate(dev, &edid_est_modes[i]);
1245 			if (newmode) {
1246 				drm_mode_probed_add(connector, newmode);
1247 				modes++;
1248 			}
1249 		}
1250 	}
1251 
1252 	if (version_greater(edid, 1, 0))
1253 		    drm_for_each_detailed_block((u8 *)edid,
1254 						do_established_modes, &closure);
1255 
1256 	return modes + closure.modes;
1257 }
1258 
1259 static void
1260 do_standard_modes(struct detailed_timing *timing, void *c)
1261 {
1262 	struct detailed_mode_closure *closure = c;
1263 	struct detailed_non_pixel *data = &timing->data.other_data;
1264 	struct drm_connector *connector = closure->connector;
1265 	struct edid *edid = closure->edid;
1266 
1267 	if (data->type == EDID_DETAIL_STD_MODES) {
1268 		int i;
1269 		for (i = 0; i < 6; i++) {
1270 			struct std_timing *std;
1271 			struct drm_display_mode *newmode;
1272 
1273 			std = &data->data.timings[i];
1274 			newmode = drm_mode_std(connector, edid, std,
1275 					       edid->revision);
1276 			if (newmode) {
1277 				drm_mode_probed_add(connector, newmode);
1278 				closure->modes++;
1279 			}
1280 		}
1281 	}
1282 }
1283 
1284 /**
1285  * add_standard_modes - get std. modes from EDID and add them
1286  * @edid: EDID block to scan
1287  *
1288  * Standard modes can be calculated using the appropriate standard (DMT,
1289  * GTF or CVT. Grab them from @edid and add them to the list.
1290  */
1291 static int
1292 add_standard_modes(struct drm_connector *connector, struct edid *edid)
1293 {
1294 	int i, modes = 0;
1295 	struct detailed_mode_closure closure = {
1296 		connector, edid, 0, 0, 0
1297 	};
1298 
1299 	for (i = 0; i < EDID_STD_TIMINGS; i++) {
1300 		struct drm_display_mode *newmode;
1301 
1302 		newmode = drm_mode_std(connector, edid,
1303 				       &edid->standard_timings[i],
1304 				       edid->revision);
1305 		if (newmode) {
1306 			drm_mode_probed_add(connector, newmode);
1307 			modes++;
1308 		}
1309 	}
1310 
1311 	if (version_greater(edid, 1, 0))
1312 		drm_for_each_detailed_block((u8 *)edid, do_standard_modes,
1313 					    &closure);
1314 
1315 	/* XXX should also look for standard codes in VTB blocks */
1316 
1317 	return modes + closure.modes;
1318 }
1319 
1320 static int drm_cvt_modes(struct drm_connector *connector,
1321 			 struct detailed_timing *timing)
1322 {
1323 	int i, j, modes = 0;
1324 	struct drm_display_mode *newmode;
1325 	struct drm_device *dev = connector->dev;
1326 	struct cvt_timing *cvt;
1327 	const int rates[] = { 60, 85, 75, 60, 50 };
1328 	const u8 empty[3] = { 0, 0, 0 };
1329 
1330 	for (i = 0; i < 4; i++) {
1331 		int uninitialized_var(width), height;
1332 		cvt = &(timing->data.other_data.data.cvt[i]);
1333 
1334 		if (!memcmp(cvt->code, empty, 3))
1335 			continue;
1336 
1337 		height = (cvt->code[0] + ((cvt->code[1] & 0xf0) << 4) + 1) * 2;
1338 		switch (cvt->code[1] & 0x0c) {
1339 		case 0x00:
1340 			width = height * 4 / 3;
1341 			break;
1342 		case 0x04:
1343 			width = height * 16 / 9;
1344 			break;
1345 		case 0x08:
1346 			width = height * 16 / 10;
1347 			break;
1348 		case 0x0c:
1349 			width = height * 15 / 9;
1350 			break;
1351 		}
1352 
1353 		for (j = 1; j < 5; j++) {
1354 			if (cvt->code[2] & (1 << j)) {
1355 				newmode = drm_cvt_mode(dev, width, height,
1356 						       rates[j], j == 0,
1357 						       false, false);
1358 				if (newmode) {
1359 					drm_mode_probed_add(connector, newmode);
1360 					modes++;
1361 				}
1362 			}
1363 		}
1364 	}
1365 
1366 	return modes;
1367 }
1368 
1369 static void
1370 do_cvt_mode(struct detailed_timing *timing, void *c)
1371 {
1372 	struct detailed_mode_closure *closure = c;
1373 	struct detailed_non_pixel *data = &timing->data.other_data;
1374 
1375 	if (data->type == EDID_DETAIL_CVT_3BYTE)
1376 		closure->modes += drm_cvt_modes(closure->connector, timing);
1377 }
1378 
1379 static int
1380 add_cvt_modes(struct drm_connector *connector, struct edid *edid)
1381 {
1382 	struct detailed_mode_closure closure = {
1383 		connector, edid, 0, 0, 0
1384 	};
1385 
1386 	if (version_greater(edid, 1, 2))
1387 		drm_for_each_detailed_block((u8 *)edid, do_cvt_mode, &closure);
1388 
1389 	/* XXX should also look for CVT codes in VTB blocks */
1390 
1391 	return closure.modes;
1392 }
1393 
1394 static void
1395 do_detailed_mode(struct detailed_timing *timing, void *c)
1396 {
1397 	struct detailed_mode_closure *closure = c;
1398 	struct drm_display_mode *newmode;
1399 
1400 	if (timing->pixel_clock) {
1401 		newmode = drm_mode_detailed(closure->connector->dev,
1402 					    closure->edid, timing,
1403 					    closure->quirks);
1404 		if (!newmode)
1405 			return;
1406 
1407 		if (closure->preferred)
1408 			newmode->type |= DRM_MODE_TYPE_PREFERRED;
1409 
1410 		drm_mode_probed_add(closure->connector, newmode);
1411 		closure->modes++;
1412 		closure->preferred = 0;
1413 	}
1414 }
1415 
1416 /*
1417  * add_detailed_modes - Add modes from detailed timings
1418  * @connector: attached connector
1419  * @edid: EDID block to scan
1420  * @quirks: quirks to apply
1421  */
1422 static int
1423 add_detailed_modes(struct drm_connector *connector, struct edid *edid,
1424 		   u32 quirks)
1425 {
1426 	struct detailed_mode_closure closure = {
1427 		connector,
1428 		edid,
1429 		1,
1430 		quirks,
1431 		0
1432 	};
1433 
1434 	if (closure.preferred && !version_greater(edid, 1, 3))
1435 		closure.preferred =
1436 		    (edid->features & DRM_EDID_FEATURE_PREFERRED_TIMING);
1437 
1438 	drm_for_each_detailed_block((u8 *)edid, do_detailed_mode, &closure);
1439 
1440 	return closure.modes;
1441 }
1442 
1443 #define HDMI_IDENTIFIER 0x000C03
1444 #define AUDIO_BLOCK	0x01
1445 #define VIDEO_BLOCK     0x02
1446 #define VENDOR_BLOCK    0x03
1447 #define SPEAKER_BLOCK	0x04
1448 #define EDID_BASIC_AUDIO	(1 << 6)
1449 #define EDID_CEA_YCRCB444	(1 << 5)
1450 #define EDID_CEA_YCRCB422	(1 << 4)
1451 
1452 /**
1453  * Search EDID for CEA extension block.
1454  */
1455 u8 *drm_find_cea_extension(struct edid *edid)
1456 {
1457 	u8 *edid_ext = NULL;
1458 	int i;
1459 
1460 	/* No EDID or EDID extensions */
1461 	if (edid == NULL || edid->extensions == 0)
1462 		return NULL;
1463 
1464 	/* Find CEA extension */
1465 	for (i = 0; i < edid->extensions; i++) {
1466 		edid_ext = (u8 *)edid + EDID_LENGTH * (i + 1);
1467 		if (edid_ext[0] == CEA_EXT)
1468 			break;
1469 	}
1470 
1471 	if (i == edid->extensions)
1472 		return NULL;
1473 
1474 	return edid_ext;
1475 }
1476 EXPORT_SYMBOL(drm_find_cea_extension);
1477 
1478 static int
1479 do_cea_modes (struct drm_connector *connector, u8 *db, u8 len)
1480 {
1481 	struct drm_device *dev = connector->dev;
1482 	u8 * mode, cea_mode;
1483 	int modes = 0;
1484 
1485 	for (mode = db; mode < db + len; mode++) {
1486 		cea_mode = (*mode & 127) - 1; /* CEA modes are numbered 1..127 */
1487 		if (cea_mode < drm_num_cea_modes) {
1488 			struct drm_display_mode *newmode;
1489 			newmode = drm_mode_duplicate(dev,
1490 						     &edid_cea_modes[cea_mode]);
1491 			if (newmode) {
1492 				drm_mode_probed_add(connector, newmode);
1493 				modes++;
1494 			}
1495 		}
1496 	}
1497 
1498 	return modes;
1499 }
1500 
1501 static int
1502 add_cea_modes(struct drm_connector *connector, struct edid *edid)
1503 {
1504 	u8 * cea = drm_find_cea_extension(edid);
1505 	u8 * db, dbl;
1506 	int modes = 0;
1507 
1508 	if (cea && cea[1] >= 3) {
1509 		for (db = cea + 4; db < cea + cea[2]; db += dbl + 1) {
1510 			dbl = db[0] & 0x1f;
1511 			if (((db[0] & 0xe0) >> 5) == VIDEO_BLOCK)
1512 				modes += do_cea_modes (connector, db+1, dbl);
1513 		}
1514 	}
1515 
1516 	return modes;
1517 }
1518 
1519 static void
1520 parse_hdmi_vsdb(struct drm_connector *connector, uint8_t *db)
1521 {
1522 	connector->eld[5] |= (db[6] >> 7) << 1;  /* Supports_AI */
1523 
1524 	connector->dvi_dual = db[6] & 1;
1525 	connector->max_tmds_clock = db[7] * 5;
1526 
1527 	connector->latency_present[0] = db[8] >> 7;
1528 	connector->latency_present[1] = (db[8] >> 6) & 1;
1529 	connector->video_latency[0] = db[9];
1530 	connector->audio_latency[0] = db[10];
1531 	connector->video_latency[1] = db[11];
1532 	connector->audio_latency[1] = db[12];
1533 
1534 	DRM_LOG_KMS("HDMI: DVI dual %d, "
1535 		    "max TMDS clock %d, "
1536 		    "latency present %d %d, "
1537 		    "video latency %d %d, "
1538 		    "audio latency %d %d\n",
1539 		    connector->dvi_dual,
1540 		    connector->max_tmds_clock,
1541 	      (int) connector->latency_present[0],
1542 	      (int) connector->latency_present[1],
1543 		    connector->video_latency[0],
1544 		    connector->video_latency[1],
1545 		    connector->audio_latency[0],
1546 		    connector->audio_latency[1]);
1547 }
1548 
1549 static void
1550 monitor_name(struct detailed_timing *t, void *data)
1551 {
1552 	if (t->data.other_data.type == EDID_DETAIL_MONITOR_NAME)
1553 		*(u8 **)data = t->data.other_data.data.str.str;
1554 }
1555 
1556 /**
1557  * drm_edid_to_eld - build ELD from EDID
1558  * @connector: connector corresponding to the HDMI/DP sink
1559  * @edid: EDID to parse
1560  *
1561  * Fill the ELD (EDID-Like Data) buffer for passing to the audio driver.
1562  * Some ELD fields are left to the graphics driver caller:
1563  * - Conn_Type
1564  * - HDCP
1565  * - Port_ID
1566  */
1567 void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
1568 {
1569 	uint8_t *eld = connector->eld;
1570 	u8 *cea;
1571 	u8 *name;
1572 	u8 *db;
1573 	int sad_count = 0;
1574 	int mnl;
1575 	int dbl;
1576 
1577 	memset(eld, 0, sizeof(connector->eld));
1578 
1579 	cea = drm_find_cea_extension(edid);
1580 	if (!cea) {
1581 		DRM_DEBUG_KMS("ELD: no CEA Extension found\n");
1582 		return;
1583 	}
1584 
1585 	name = NULL;
1586 	drm_for_each_detailed_block((u8 *)edid, monitor_name, &name);
1587 	for (mnl = 0; name && mnl < 13; mnl++) {
1588 		if (name[mnl] == 0x0a)
1589 			break;
1590 		eld[20 + mnl] = name[mnl];
1591 	}
1592 	eld[4] = (cea[1] << 5) | mnl;
1593 	DRM_DEBUG_KMS("ELD monitor %s\n", eld + 20);
1594 
1595 	eld[0] = 2 << 3;		/* ELD version: 2 */
1596 
1597 	eld[16] = edid->mfg_id[0];
1598 	eld[17] = edid->mfg_id[1];
1599 	eld[18] = edid->prod_code[0];
1600 	eld[19] = edid->prod_code[1];
1601 
1602 	if (cea[1] >= 3)
1603 		for (db = cea + 4; db < cea + cea[2]; db += dbl + 1) {
1604 			dbl = db[0] & 0x1f;
1605 
1606 			switch ((db[0] & 0xe0) >> 5) {
1607 			case AUDIO_BLOCK:
1608 				/* Audio Data Block, contains SADs */
1609 				sad_count = dbl / 3;
1610 				memcpy(eld + 20 + mnl, &db[1], dbl);
1611 				break;
1612 			case SPEAKER_BLOCK:
1613                                 /* Speaker Allocation Data Block */
1614 				eld[7] = db[1];
1615 				break;
1616 			case VENDOR_BLOCK:
1617 				/* HDMI Vendor-Specific Data Block */
1618 				if (db[1] == 0x03 && db[2] == 0x0c && db[3] == 0)
1619 					parse_hdmi_vsdb(connector, db);
1620 				break;
1621 			default:
1622 				break;
1623 			}
1624 		}
1625 	eld[5] |= sad_count << 4;
1626 	eld[2] = (20 + mnl + sad_count * 3 + 3) / 4;
1627 
1628 	DRM_DEBUG_KMS("ELD size %d, SAD count %d\n", (int)eld[2], sad_count);
1629 }
1630 EXPORT_SYMBOL(drm_edid_to_eld);
1631 
1632 /**
1633  * drm_av_sync_delay - HDMI/DP sink audio-video sync delay in millisecond
1634  * @connector: connector associated with the HDMI/DP sink
1635  * @mode: the display mode
1636  */
1637 int drm_av_sync_delay(struct drm_connector *connector,
1638 		      struct drm_display_mode *mode)
1639 {
1640 	int i = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
1641 	int a, v;
1642 
1643 	if (!connector->latency_present[0])
1644 		return 0;
1645 	if (!connector->latency_present[1])
1646 		i = 0;
1647 
1648 	a = connector->audio_latency[i];
1649 	v = connector->video_latency[i];
1650 
1651 	/*
1652 	 * HDMI/DP sink doesn't support audio or video?
1653 	 */
1654 	if (a == 255 || v == 255)
1655 		return 0;
1656 
1657 	/*
1658 	 * Convert raw EDID values to millisecond.
1659 	 * Treat unknown latency as 0ms.
1660 	 */
1661 	if (a)
1662 		a = min(2 * (a - 1), 500);
1663 	if (v)
1664 		v = min(2 * (v - 1), 500);
1665 
1666 	return max(v - a, 0);
1667 }
1668 EXPORT_SYMBOL(drm_av_sync_delay);
1669 
1670 /**
1671  * drm_select_eld - select one ELD from multiple HDMI/DP sinks
1672  * @encoder: the encoder just changed display mode
1673  * @mode: the adjusted display mode
1674  *
1675  * It's possible for one encoder to be associated with multiple HDMI/DP sinks.
1676  * The policy is now hard coded to simply use the first HDMI/DP sink's ELD.
1677  */
1678 struct drm_connector *drm_select_eld(struct drm_encoder *encoder,
1679 				     struct drm_display_mode *mode)
1680 {
1681 	struct drm_connector *connector;
1682 	struct drm_device *dev = encoder->dev;
1683 
1684 	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
1685 		if (connector->encoder == encoder && connector->eld[0])
1686 			return connector;
1687 
1688 	return NULL;
1689 }
1690 EXPORT_SYMBOL(drm_select_eld);
1691 
1692 /**
1693  * drm_detect_hdmi_monitor - detect whether monitor is hdmi.
1694  * @edid: monitor EDID information
1695  *
1696  * Parse the CEA extension according to CEA-861-B.
1697  * Return true if HDMI, false if not or unknown.
1698  */
1699 bool drm_detect_hdmi_monitor(struct edid *edid)
1700 {
1701 	u8 *edid_ext;
1702 	int i, hdmi_id;
1703 	int start_offset, end_offset;
1704 	bool is_hdmi = false;
1705 
1706 	edid_ext = drm_find_cea_extension(edid);
1707 	if (!edid_ext)
1708 		goto end;
1709 
1710 	/* Data block offset in CEA extension block */
1711 	start_offset = 4;
1712 	end_offset = edid_ext[2];
1713 
1714 	/*
1715 	 * Because HDMI identifier is in Vendor Specific Block,
1716 	 * search it from all data blocks of CEA extension.
1717 	 */
1718 	for (i = start_offset; i < end_offset;
1719 		/* Increased by data block len */
1720 		i += ((edid_ext[i] & 0x1f) + 1)) {
1721 		/* Find vendor specific block */
1722 		if ((edid_ext[i] >> 5) == VENDOR_BLOCK) {
1723 			hdmi_id = edid_ext[i + 1] | (edid_ext[i + 2] << 8) |
1724 				  edid_ext[i + 3] << 16;
1725 			/* Find HDMI identifier */
1726 			if (hdmi_id == HDMI_IDENTIFIER)
1727 				is_hdmi = true;
1728 			break;
1729 		}
1730 	}
1731 
1732 end:
1733 	return is_hdmi;
1734 }
1735 EXPORT_SYMBOL(drm_detect_hdmi_monitor);
1736 
1737 /**
1738  * drm_detect_monitor_audio - check monitor audio capability
1739  *
1740  * Monitor should have CEA extension block.
1741  * If monitor has 'basic audio', but no CEA audio blocks, it's 'basic
1742  * audio' only. If there is any audio extension block and supported
1743  * audio format, assume at least 'basic audio' support, even if 'basic
1744  * audio' is not defined in EDID.
1745  *
1746  */
1747 bool drm_detect_monitor_audio(struct edid *edid)
1748 {
1749 	u8 *edid_ext;
1750 	int i, j;
1751 	bool has_audio = false;
1752 	int start_offset, end_offset;
1753 
1754 	edid_ext = drm_find_cea_extension(edid);
1755 	if (!edid_ext)
1756 		goto end;
1757 
1758 	has_audio = ((edid_ext[3] & EDID_BASIC_AUDIO) != 0);
1759 
1760 	if (has_audio) {
1761 		DRM_DEBUG_KMS("Monitor has basic audio support\n");
1762 		goto end;
1763 	}
1764 
1765 	/* Data block offset in CEA extension block */
1766 	start_offset = 4;
1767 	end_offset = edid_ext[2];
1768 
1769 	for (i = start_offset; i < end_offset;
1770 			i += ((edid_ext[i] & 0x1f) + 1)) {
1771 		if ((edid_ext[i] >> 5) == AUDIO_BLOCK) {
1772 			has_audio = true;
1773 			for (j = 1; j < (edid_ext[i] & 0x1f); j += 3)
1774 				DRM_DEBUG_KMS("CEA audio format %d\n",
1775 					      (edid_ext[i + j] >> 3) & 0xf);
1776 			goto end;
1777 		}
1778 	}
1779 end:
1780 	return has_audio;
1781 }
1782 EXPORT_SYMBOL(drm_detect_monitor_audio);
1783 
1784 /**
1785  * drm_add_display_info - pull display info out if present
1786  * @edid: EDID data
1787  * @info: display info (attached to connector)
1788  *
1789  * Grab any available display info and stuff it into the drm_display_info
1790  * structure that's part of the connector.  Useful for tracking bpp and
1791  * color spaces.
1792  */
1793 static void drm_add_display_info(struct edid *edid,
1794 				 struct drm_display_info *info)
1795 {
1796 	u8 *edid_ext;
1797 
1798 	info->width_mm = edid->width_cm * 10;
1799 	info->height_mm = edid->height_cm * 10;
1800 
1801 	/* driver figures it out in this case */
1802 	info->bpc = 0;
1803 	info->color_formats = 0;
1804 
1805 	if (edid->revision < 3)
1806 		return;
1807 
1808 	if (!(edid->input & DRM_EDID_INPUT_DIGITAL))
1809 		return;
1810 
1811 	/* Get data from CEA blocks if present */
1812 	edid_ext = drm_find_cea_extension(edid);
1813 	if (edid_ext) {
1814 		info->cea_rev = edid_ext[1];
1815 
1816 		/* The existence of a CEA block should imply RGB support */
1817 		info->color_formats = DRM_COLOR_FORMAT_RGB444;
1818 		if (edid_ext[3] & EDID_CEA_YCRCB444)
1819 			info->color_formats |= DRM_COLOR_FORMAT_YCRCB444;
1820 		if (edid_ext[3] & EDID_CEA_YCRCB422)
1821 			info->color_formats |= DRM_COLOR_FORMAT_YCRCB422;
1822 	}
1823 
1824 	/* Only defined for 1.4 with digital displays */
1825 	if (edid->revision < 4)
1826 		return;
1827 
1828 	switch (edid->input & DRM_EDID_DIGITAL_DEPTH_MASK) {
1829 	case DRM_EDID_DIGITAL_DEPTH_6:
1830 		info->bpc = 6;
1831 		break;
1832 	case DRM_EDID_DIGITAL_DEPTH_8:
1833 		info->bpc = 8;
1834 		break;
1835 	case DRM_EDID_DIGITAL_DEPTH_10:
1836 		info->bpc = 10;
1837 		break;
1838 	case DRM_EDID_DIGITAL_DEPTH_12:
1839 		info->bpc = 12;
1840 		break;
1841 	case DRM_EDID_DIGITAL_DEPTH_14:
1842 		info->bpc = 14;
1843 		break;
1844 	case DRM_EDID_DIGITAL_DEPTH_16:
1845 		info->bpc = 16;
1846 		break;
1847 	case DRM_EDID_DIGITAL_DEPTH_UNDEF:
1848 	default:
1849 		info->bpc = 0;
1850 		break;
1851 	}
1852 
1853 	info->color_formats |= DRM_COLOR_FORMAT_RGB444;
1854 	if (edid->features & DRM_EDID_FEATURE_RGB_YCRCB444)
1855 		info->color_formats |= DRM_COLOR_FORMAT_YCRCB444;
1856 	if (edid->features & DRM_EDID_FEATURE_RGB_YCRCB422)
1857 		info->color_formats |= DRM_COLOR_FORMAT_YCRCB422;
1858 }
1859 
1860 /**
1861  * drm_add_edid_modes - add modes from EDID data, if available
1862  * @connector: connector we're probing
1863  * @edid: edid data
1864  *
1865  * Add the specified modes to the connector's mode list.
1866  *
1867  * Return number of modes added or 0 if we couldn't find any.
1868  */
1869 int drm_add_edid_modes(struct drm_connector *connector, struct edid *edid)
1870 {
1871 	int num_modes = 0;
1872 	u32 quirks;
1873 
1874 	if (edid == NULL) {
1875 		return 0;
1876 	}
1877 	if (!drm_edid_is_valid(edid)) {
1878 		dev_warn(connector->dev->dev, "%s: EDID invalid.\n",
1879 			 drm_get_connector_name(connector));
1880 		return 0;
1881 	}
1882 
1883 	quirks = edid_get_quirks(edid);
1884 
1885 	/*
1886 	 * EDID spec says modes should be preferred in this order:
1887 	 * - preferred detailed mode
1888 	 * - other detailed modes from base block
1889 	 * - detailed modes from extension blocks
1890 	 * - CVT 3-byte code modes
1891 	 * - standard timing codes
1892 	 * - established timing codes
1893 	 * - modes inferred from GTF or CVT range information
1894 	 *
1895 	 * We get this pretty much right.
1896 	 *
1897 	 * XXX order for additional mode types in extension blocks?
1898 	 */
1899 	num_modes += add_detailed_modes(connector, edid, quirks);
1900 	num_modes += add_cvt_modes(connector, edid);
1901 	num_modes += add_standard_modes(connector, edid);
1902 	num_modes += add_established_modes(connector, edid);
1903 	num_modes += add_inferred_modes(connector, edid);
1904 	num_modes += add_cea_modes(connector, edid);
1905 
1906 	if (quirks & (EDID_QUIRK_PREFER_LARGE_60 | EDID_QUIRK_PREFER_LARGE_75))
1907 		edid_fixup_preferred(connector, quirks);
1908 
1909 	drm_add_display_info(edid, &connector->display_info);
1910 
1911 	return num_modes;
1912 }
1913 EXPORT_SYMBOL(drm_add_edid_modes);
1914 
1915 /**
1916  * drm_add_modes_noedid - add modes for the connectors without EDID
1917  * @connector: connector we're probing
1918  * @hdisplay: the horizontal display limit
1919  * @vdisplay: the vertical display limit
1920  *
1921  * Add the specified modes to the connector's mode list. Only when the
1922  * hdisplay/vdisplay is not beyond the given limit, it will be added.
1923  *
1924  * Return number of modes added or 0 if we couldn't find any.
1925  */
1926 int drm_add_modes_noedid(struct drm_connector *connector,
1927 			int hdisplay, int vdisplay)
1928 {
1929 	int i, count, num_modes = 0;
1930 	struct drm_display_mode *mode;
1931 	struct drm_device *dev = connector->dev;
1932 
1933 	count = sizeof(drm_dmt_modes) / sizeof(struct drm_display_mode);
1934 	if (hdisplay < 0)
1935 		hdisplay = 0;
1936 	if (vdisplay < 0)
1937 		vdisplay = 0;
1938 
1939 	for (i = 0; i < count; i++) {
1940 		const struct drm_display_mode *ptr = &drm_dmt_modes[i];
1941 		if (hdisplay && vdisplay) {
1942 			/*
1943 			 * Only when two are valid, they will be used to check
1944 			 * whether the mode should be added to the mode list of
1945 			 * the connector.
1946 			 */
1947 			if (ptr->hdisplay > hdisplay ||
1948 					ptr->vdisplay > vdisplay)
1949 				continue;
1950 		}
1951 		if (drm_mode_vrefresh(ptr) > 61)
1952 			continue;
1953 		mode = drm_mode_duplicate(dev, ptr);
1954 		if (mode) {
1955 			drm_mode_probed_add(connector, mode);
1956 			num_modes++;
1957 		}
1958 	}
1959 	return num_modes;
1960 }
1961 EXPORT_SYMBOL(drm_add_modes_noedid);
1962