xref: /openbmc/linux/drivers/gpu/drm/drm_edid.c (revision 81d67439)
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 "drmP.h"
34 #include "drm_edid.h"
35 #include "drm_edid_modes.h"
36 
37 #define version_greater(edid, maj, min) \
38 	(((edid)->version > (maj)) || \
39 	 ((edid)->version == (maj) && (edid)->revision > (min)))
40 
41 #define EDID_EST_TIMINGS 16
42 #define EDID_STD_TIMINGS 8
43 #define EDID_DETAILED_TIMINGS 4
44 
45 /*
46  * EDID blocks out in the wild have a variety of bugs, try to collect
47  * them here (note that userspace may work around broken monitors first,
48  * but fixes should make their way here so that the kernel "just works"
49  * on as many displays as possible).
50  */
51 
52 /* First detailed mode wrong, use largest 60Hz mode */
53 #define EDID_QUIRK_PREFER_LARGE_60		(1 << 0)
54 /* Reported 135MHz pixel clock is too high, needs adjustment */
55 #define EDID_QUIRK_135_CLOCK_TOO_HIGH		(1 << 1)
56 /* Prefer the largest mode at 75 Hz */
57 #define EDID_QUIRK_PREFER_LARGE_75		(1 << 2)
58 /* Detail timing is in cm not mm */
59 #define EDID_QUIRK_DETAILED_IN_CM		(1 << 3)
60 /* Detailed timing descriptors have bogus size values, so just take the
61  * maximum size and use that.
62  */
63 #define EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE	(1 << 4)
64 /* Monitor forgot to set the first detailed is preferred bit. */
65 #define EDID_QUIRK_FIRST_DETAILED_PREFERRED	(1 << 5)
66 /* use +hsync +vsync for detailed mode */
67 #define EDID_QUIRK_DETAILED_SYNC_PP		(1 << 6)
68 
69 struct detailed_mode_closure {
70 	struct drm_connector *connector;
71 	struct edid *edid;
72 	bool preferred;
73 	u32 quirks;
74 	int modes;
75 };
76 
77 #define LEVEL_DMT	0
78 #define LEVEL_GTF	1
79 #define LEVEL_GTF2	2
80 #define LEVEL_CVT	3
81 
82 static struct edid_quirk {
83 	char *vendor;
84 	int product_id;
85 	u32 quirks;
86 } edid_quirk_list[] = {
87 	/* Acer AL1706 */
88 	{ "ACR", 44358, EDID_QUIRK_PREFER_LARGE_60 },
89 	/* Acer F51 */
90 	{ "API", 0x7602, EDID_QUIRK_PREFER_LARGE_60 },
91 	/* Unknown Acer */
92 	{ "ACR", 2423, EDID_QUIRK_FIRST_DETAILED_PREFERRED },
93 
94 	/* Belinea 10 15 55 */
95 	{ "MAX", 1516, EDID_QUIRK_PREFER_LARGE_60 },
96 	{ "MAX", 0x77e, EDID_QUIRK_PREFER_LARGE_60 },
97 
98 	/* Envision Peripherals, Inc. EN-7100e */
99 	{ "EPI", 59264, EDID_QUIRK_135_CLOCK_TOO_HIGH },
100 	/* Envision EN2028 */
101 	{ "EPI", 8232, EDID_QUIRK_PREFER_LARGE_60 },
102 
103 	/* Funai Electronics PM36B */
104 	{ "FCM", 13600, EDID_QUIRK_PREFER_LARGE_75 |
105 	  EDID_QUIRK_DETAILED_IN_CM },
106 
107 	/* LG Philips LCD LP154W01-A5 */
108 	{ "LPL", 0, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE },
109 	{ "LPL", 0x2a00, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE },
110 
111 	/* Philips 107p5 CRT */
112 	{ "PHL", 57364, EDID_QUIRK_FIRST_DETAILED_PREFERRED },
113 
114 	/* Proview AY765C */
115 	{ "PTS", 765, EDID_QUIRK_FIRST_DETAILED_PREFERRED },
116 
117 	/* Samsung SyncMaster 205BW.  Note: irony */
118 	{ "SAM", 541, EDID_QUIRK_DETAILED_SYNC_PP },
119 	/* Samsung SyncMaster 22[5-6]BW */
120 	{ "SAM", 596, EDID_QUIRK_PREFER_LARGE_60 },
121 	{ "SAM", 638, EDID_QUIRK_PREFER_LARGE_60 },
122 };
123 
124 /*** DDC fetch and block validation ***/
125 
126 static const u8 edid_header[] = {
127 	0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00
128 };
129 
130 /*
131  * Sanity check the EDID block (base or extension).  Return 0 if the block
132  * doesn't check out, or 1 if it's valid.
133  */
134 static bool
135 drm_edid_block_valid(u8 *raw_edid)
136 {
137 	int i;
138 	u8 csum = 0;
139 	struct edid *edid = (struct edid *)raw_edid;
140 
141 	if (raw_edid[0] == 0x00) {
142 		int score = 0;
143 
144 		for (i = 0; i < sizeof(edid_header); i++)
145 			if (raw_edid[i] == edid_header[i])
146 				score++;
147 
148 		if (score == 8) ;
149 		else if (score >= 6) {
150 			DRM_DEBUG("Fixing EDID header, your hardware may be failing\n");
151 			memcpy(raw_edid, edid_header, sizeof(edid_header));
152 		} else {
153 			goto bad;
154 		}
155 	}
156 
157 	for (i = 0; i < EDID_LENGTH; i++)
158 		csum += raw_edid[i];
159 	if (csum) {
160 		DRM_ERROR("EDID checksum is invalid, remainder is %d\n", csum);
161 
162 		/* allow CEA to slide through, switches mangle this */
163 		if (raw_edid[0] != 0x02)
164 			goto bad;
165 	}
166 
167 	/* per-block-type checks */
168 	switch (raw_edid[0]) {
169 	case 0: /* base */
170 		if (edid->version != 1) {
171 			DRM_ERROR("EDID has major version %d, instead of 1\n", edid->version);
172 			goto bad;
173 		}
174 
175 		if (edid->revision > 4)
176 			DRM_DEBUG("EDID minor > 4, assuming backward compatibility\n");
177 		break;
178 
179 	default:
180 		break;
181 	}
182 
183 	return 1;
184 
185 bad:
186 	if (raw_edid) {
187 		printk(KERN_ERR "Raw EDID:\n");
188 		print_hex_dump_bytes(KERN_ERR, DUMP_PREFIX_NONE, raw_edid, EDID_LENGTH);
189 		printk(KERN_ERR "\n");
190 	}
191 	return 0;
192 }
193 
194 /**
195  * drm_edid_is_valid - sanity check EDID data
196  * @edid: EDID data
197  *
198  * Sanity-check an entire EDID record (including extensions)
199  */
200 bool drm_edid_is_valid(struct edid *edid)
201 {
202 	int i;
203 	u8 *raw = (u8 *)edid;
204 
205 	if (!edid)
206 		return false;
207 
208 	for (i = 0; i <= edid->extensions; i++)
209 		if (!drm_edid_block_valid(raw + i * EDID_LENGTH))
210 			return false;
211 
212 	return true;
213 }
214 EXPORT_SYMBOL(drm_edid_is_valid);
215 
216 #define DDC_ADDR 0x50
217 #define DDC_SEGMENT_ADDR 0x30
218 /**
219  * Get EDID information via I2C.
220  *
221  * \param adapter : i2c device adaptor
222  * \param buf     : EDID data buffer to be filled
223  * \param len     : EDID data buffer length
224  * \return 0 on success or -1 on failure.
225  *
226  * Try to fetch EDID information by calling i2c driver function.
227  */
228 static int
229 drm_do_probe_ddc_edid(struct i2c_adapter *adapter, unsigned char *buf,
230 		      int block, int len)
231 {
232 	unsigned char start = block * EDID_LENGTH;
233 	int ret, retries = 5;
234 
235 	/* The core i2c driver will automatically retry the transfer if the
236 	 * adapter reports EAGAIN. However, we find that bit-banging transfers
237 	 * are susceptible to errors under a heavily loaded machine and
238 	 * generate spurious NAKs and timeouts. Retrying the transfer
239 	 * of the individual block a few times seems to overcome this.
240 	 */
241 	do {
242 		struct i2c_msg msgs[] = {
243 			{
244 				.addr	= DDC_ADDR,
245 				.flags	= 0,
246 				.len	= 1,
247 				.buf	= &start,
248 			}, {
249 				.addr	= DDC_ADDR,
250 				.flags	= I2C_M_RD,
251 				.len	= len,
252 				.buf	= buf,
253 			}
254 		};
255 		ret = i2c_transfer(adapter, msgs, 2);
256 	} while (ret != 2 && --retries);
257 
258 	return ret == 2 ? 0 : -1;
259 }
260 
261 static bool drm_edid_is_zero(u8 *in_edid, int length)
262 {
263 	int i;
264 	u32 *raw_edid = (u32 *)in_edid;
265 
266 	for (i = 0; i < length / 4; i++)
267 		if (*(raw_edid + i) != 0)
268 			return false;
269 	return true;
270 }
271 
272 static u8 *
273 drm_do_get_edid(struct drm_connector *connector, struct i2c_adapter *adapter)
274 {
275 	int i, j = 0, valid_extensions = 0;
276 	u8 *block, *new;
277 
278 	if ((block = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL)
279 		return NULL;
280 
281 	/* base block fetch */
282 	for (i = 0; i < 4; i++) {
283 		if (drm_do_probe_ddc_edid(adapter, block, 0, EDID_LENGTH))
284 			goto out;
285 		if (drm_edid_block_valid(block))
286 			break;
287 		if (i == 0 && drm_edid_is_zero(block, EDID_LENGTH)) {
288 			connector->null_edid_counter++;
289 			goto carp;
290 		}
291 	}
292 	if (i == 4)
293 		goto carp;
294 
295 	/* if there's no extensions, we're done */
296 	if (block[0x7e] == 0)
297 		return block;
298 
299 	new = krealloc(block, (block[0x7e] + 1) * EDID_LENGTH, GFP_KERNEL);
300 	if (!new)
301 		goto out;
302 	block = new;
303 
304 	for (j = 1; j <= block[0x7e]; j++) {
305 		for (i = 0; i < 4; i++) {
306 			if (drm_do_probe_ddc_edid(adapter,
307 				  block + (valid_extensions + 1) * EDID_LENGTH,
308 				  j, EDID_LENGTH))
309 				goto out;
310 			if (drm_edid_block_valid(block + (valid_extensions + 1) * EDID_LENGTH)) {
311 				valid_extensions++;
312 				break;
313 			}
314 		}
315 		if (i == 4)
316 			dev_warn(connector->dev->dev,
317 			 "%s: Ignoring invalid EDID block %d.\n",
318 			 drm_get_connector_name(connector), j);
319 	}
320 
321 	if (valid_extensions != block[0x7e]) {
322 		block[EDID_LENGTH-1] += block[0x7e] - valid_extensions;
323 		block[0x7e] = valid_extensions;
324 		new = krealloc(block, (valid_extensions + 1) * EDID_LENGTH, GFP_KERNEL);
325 		if (!new)
326 			goto out;
327 		block = new;
328 	}
329 
330 	return block;
331 
332 carp:
333 	dev_warn(connector->dev->dev, "%s: EDID block %d invalid.\n",
334 		 drm_get_connector_name(connector), j);
335 
336 out:
337 	kfree(block);
338 	return NULL;
339 }
340 
341 /**
342  * Probe DDC presence.
343  *
344  * \param adapter : i2c device adaptor
345  * \return 1 on success
346  */
347 static bool
348 drm_probe_ddc(struct i2c_adapter *adapter)
349 {
350 	unsigned char out;
351 
352 	return (drm_do_probe_ddc_edid(adapter, &out, 0, 1) == 0);
353 }
354 
355 /**
356  * drm_get_edid - get EDID data, if available
357  * @connector: connector we're probing
358  * @adapter: i2c adapter to use for DDC
359  *
360  * Poke the given i2c channel to grab EDID data if possible.  If found,
361  * attach it to the connector.
362  *
363  * Return edid data or NULL if we couldn't find any.
364  */
365 struct edid *drm_get_edid(struct drm_connector *connector,
366 			  struct i2c_adapter *adapter)
367 {
368 	struct edid *edid = NULL;
369 
370 	if (drm_probe_ddc(adapter))
371 		edid = (struct edid *)drm_do_get_edid(connector, adapter);
372 
373 	connector->display_info.raw_edid = (char *)edid;
374 
375 	return edid;
376 
377 }
378 EXPORT_SYMBOL(drm_get_edid);
379 
380 /*** EDID parsing ***/
381 
382 /**
383  * edid_vendor - match a string against EDID's obfuscated vendor field
384  * @edid: EDID to match
385  * @vendor: vendor string
386  *
387  * Returns true if @vendor is in @edid, false otherwise
388  */
389 static bool edid_vendor(struct edid *edid, char *vendor)
390 {
391 	char edid_vendor[3];
392 
393 	edid_vendor[0] = ((edid->mfg_id[0] & 0x7c) >> 2) + '@';
394 	edid_vendor[1] = (((edid->mfg_id[0] & 0x3) << 3) |
395 			  ((edid->mfg_id[1] & 0xe0) >> 5)) + '@';
396 	edid_vendor[2] = (edid->mfg_id[1] & 0x1f) + '@';
397 
398 	return !strncmp(edid_vendor, vendor, 3);
399 }
400 
401 /**
402  * edid_get_quirks - return quirk flags for a given EDID
403  * @edid: EDID to process
404  *
405  * This tells subsequent routines what fixes they need to apply.
406  */
407 static u32 edid_get_quirks(struct edid *edid)
408 {
409 	struct edid_quirk *quirk;
410 	int i;
411 
412 	for (i = 0; i < ARRAY_SIZE(edid_quirk_list); i++) {
413 		quirk = &edid_quirk_list[i];
414 
415 		if (edid_vendor(edid, quirk->vendor) &&
416 		    (EDID_PRODUCT_ID(edid) == quirk->product_id))
417 			return quirk->quirks;
418 	}
419 
420 	return 0;
421 }
422 
423 #define MODE_SIZE(m) ((m)->hdisplay * (m)->vdisplay)
424 #define MODE_REFRESH_DIFF(m,r) (abs((m)->vrefresh - target_refresh))
425 
426 /**
427  * edid_fixup_preferred - set preferred modes based on quirk list
428  * @connector: has mode list to fix up
429  * @quirks: quirks list
430  *
431  * Walk the mode list for @connector, clearing the preferred status
432  * on existing modes and setting it anew for the right mode ala @quirks.
433  */
434 static void edid_fixup_preferred(struct drm_connector *connector,
435 				 u32 quirks)
436 {
437 	struct drm_display_mode *t, *cur_mode, *preferred_mode;
438 	int target_refresh = 0;
439 
440 	if (list_empty(&connector->probed_modes))
441 		return;
442 
443 	if (quirks & EDID_QUIRK_PREFER_LARGE_60)
444 		target_refresh = 60;
445 	if (quirks & EDID_QUIRK_PREFER_LARGE_75)
446 		target_refresh = 75;
447 
448 	preferred_mode = list_first_entry(&connector->probed_modes,
449 					  struct drm_display_mode, head);
450 
451 	list_for_each_entry_safe(cur_mode, t, &connector->probed_modes, head) {
452 		cur_mode->type &= ~DRM_MODE_TYPE_PREFERRED;
453 
454 		if (cur_mode == preferred_mode)
455 			continue;
456 
457 		/* Largest mode is preferred */
458 		if (MODE_SIZE(cur_mode) > MODE_SIZE(preferred_mode))
459 			preferred_mode = cur_mode;
460 
461 		/* At a given size, try to get closest to target refresh */
462 		if ((MODE_SIZE(cur_mode) == MODE_SIZE(preferred_mode)) &&
463 		    MODE_REFRESH_DIFF(cur_mode, target_refresh) <
464 		    MODE_REFRESH_DIFF(preferred_mode, target_refresh)) {
465 			preferred_mode = cur_mode;
466 		}
467 	}
468 
469 	preferred_mode->type |= DRM_MODE_TYPE_PREFERRED;
470 }
471 
472 struct drm_display_mode *drm_mode_find_dmt(struct drm_device *dev,
473 					   int hsize, int vsize, int fresh)
474 {
475 	struct drm_display_mode *mode = NULL;
476 	int i;
477 
478 	for (i = 0; i < drm_num_dmt_modes; i++) {
479 		const struct drm_display_mode *ptr = &drm_dmt_modes[i];
480 		if (hsize == ptr->hdisplay &&
481 			vsize == ptr->vdisplay &&
482 			fresh == drm_mode_vrefresh(ptr)) {
483 			/* get the expected default mode */
484 			mode = drm_mode_duplicate(dev, ptr);
485 			break;
486 		}
487 	}
488 	return mode;
489 }
490 EXPORT_SYMBOL(drm_mode_find_dmt);
491 
492 typedef void detailed_cb(struct detailed_timing *timing, void *closure);
493 
494 static void
495 cea_for_each_detailed_block(u8 *ext, detailed_cb *cb, void *closure)
496 {
497 	int i, n = 0;
498 	u8 rev = ext[0x01], d = ext[0x02];
499 	u8 *det_base = ext + d;
500 
501 	switch (rev) {
502 	case 0:
503 		/* can't happen */
504 		return;
505 	case 1:
506 		/* have to infer how many blocks we have, check pixel clock */
507 		for (i = 0; i < 6; i++)
508 			if (det_base[18*i] || det_base[18*i+1])
509 				n++;
510 		break;
511 	default:
512 		/* explicit count */
513 		n = min(ext[0x03] & 0x0f, 6);
514 		break;
515 	}
516 
517 	for (i = 0; i < n; i++)
518 		cb((struct detailed_timing *)(det_base + 18 * i), closure);
519 }
520 
521 static void
522 vtb_for_each_detailed_block(u8 *ext, detailed_cb *cb, void *closure)
523 {
524 	unsigned int i, n = min((int)ext[0x02], 6);
525 	u8 *det_base = ext + 5;
526 
527 	if (ext[0x01] != 1)
528 		return; /* unknown version */
529 
530 	for (i = 0; i < n; i++)
531 		cb((struct detailed_timing *)(det_base + 18 * i), closure);
532 }
533 
534 static void
535 drm_for_each_detailed_block(u8 *raw_edid, detailed_cb *cb, void *closure)
536 {
537 	int i;
538 	struct edid *edid = (struct edid *)raw_edid;
539 
540 	if (edid == NULL)
541 		return;
542 
543 	for (i = 0; i < EDID_DETAILED_TIMINGS; i++)
544 		cb(&(edid->detailed_timings[i]), closure);
545 
546 	for (i = 1; i <= raw_edid[0x7e]; i++) {
547 		u8 *ext = raw_edid + (i * EDID_LENGTH);
548 		switch (*ext) {
549 		case CEA_EXT:
550 			cea_for_each_detailed_block(ext, cb, closure);
551 			break;
552 		case VTB_EXT:
553 			vtb_for_each_detailed_block(ext, cb, closure);
554 			break;
555 		default:
556 			break;
557 		}
558 	}
559 }
560 
561 static void
562 is_rb(struct detailed_timing *t, void *data)
563 {
564 	u8 *r = (u8 *)t;
565 	if (r[3] == EDID_DETAIL_MONITOR_RANGE)
566 		if (r[15] & 0x10)
567 			*(bool *)data = true;
568 }
569 
570 /* EDID 1.4 defines this explicitly.  For EDID 1.3, we guess, badly. */
571 static bool
572 drm_monitor_supports_rb(struct edid *edid)
573 {
574 	if (edid->revision >= 4) {
575 		bool ret;
576 		drm_for_each_detailed_block((u8 *)edid, is_rb, &ret);
577 		return ret;
578 	}
579 
580 	return ((edid->input & DRM_EDID_INPUT_DIGITAL) != 0);
581 }
582 
583 static void
584 find_gtf2(struct detailed_timing *t, void *data)
585 {
586 	u8 *r = (u8 *)t;
587 	if (r[3] == EDID_DETAIL_MONITOR_RANGE && r[10] == 0x02)
588 		*(u8 **)data = r;
589 }
590 
591 /* Secondary GTF curve kicks in above some break frequency */
592 static int
593 drm_gtf2_hbreak(struct edid *edid)
594 {
595 	u8 *r = NULL;
596 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
597 	return r ? (r[12] * 2) : 0;
598 }
599 
600 static int
601 drm_gtf2_2c(struct edid *edid)
602 {
603 	u8 *r = NULL;
604 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
605 	return r ? r[13] : 0;
606 }
607 
608 static int
609 drm_gtf2_m(struct edid *edid)
610 {
611 	u8 *r = NULL;
612 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
613 	return r ? (r[15] << 8) + r[14] : 0;
614 }
615 
616 static int
617 drm_gtf2_k(struct edid *edid)
618 {
619 	u8 *r = NULL;
620 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
621 	return r ? r[16] : 0;
622 }
623 
624 static int
625 drm_gtf2_2j(struct edid *edid)
626 {
627 	u8 *r = NULL;
628 	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
629 	return r ? r[17] : 0;
630 }
631 
632 /**
633  * standard_timing_level - get std. timing level(CVT/GTF/DMT)
634  * @edid: EDID block to scan
635  */
636 static int standard_timing_level(struct edid *edid)
637 {
638 	if (edid->revision >= 2) {
639 		if (edid->revision >= 4 && (edid->features & DRM_EDID_FEATURE_DEFAULT_GTF))
640 			return LEVEL_CVT;
641 		if (drm_gtf2_hbreak(edid))
642 			return LEVEL_GTF2;
643 		return LEVEL_GTF;
644 	}
645 	return LEVEL_DMT;
646 }
647 
648 /*
649  * 0 is reserved.  The spec says 0x01 fill for unused timings.  Some old
650  * monitors fill with ascii space (0x20) instead.
651  */
652 static int
653 bad_std_timing(u8 a, u8 b)
654 {
655 	return (a == 0x00 && b == 0x00) ||
656 	       (a == 0x01 && b == 0x01) ||
657 	       (a == 0x20 && b == 0x20);
658 }
659 
660 /**
661  * drm_mode_std - convert standard mode info (width, height, refresh) into mode
662  * @t: standard timing params
663  * @timing_level: standard timing level
664  *
665  * Take the standard timing params (in this case width, aspect, and refresh)
666  * and convert them into a real mode using CVT/GTF/DMT.
667  */
668 static struct drm_display_mode *
669 drm_mode_std(struct drm_connector *connector, struct edid *edid,
670 	     struct std_timing *t, int revision)
671 {
672 	struct drm_device *dev = connector->dev;
673 	struct drm_display_mode *m, *mode = NULL;
674 	int hsize, vsize;
675 	int vrefresh_rate;
676 	unsigned aspect_ratio = (t->vfreq_aspect & EDID_TIMING_ASPECT_MASK)
677 		>> EDID_TIMING_ASPECT_SHIFT;
678 	unsigned vfreq = (t->vfreq_aspect & EDID_TIMING_VFREQ_MASK)
679 		>> EDID_TIMING_VFREQ_SHIFT;
680 	int timing_level = standard_timing_level(edid);
681 
682 	if (bad_std_timing(t->hsize, t->vfreq_aspect))
683 		return NULL;
684 
685 	/* According to the EDID spec, the hdisplay = hsize * 8 + 248 */
686 	hsize = t->hsize * 8 + 248;
687 	/* vrefresh_rate = vfreq + 60 */
688 	vrefresh_rate = vfreq + 60;
689 	/* the vdisplay is calculated based on the aspect ratio */
690 	if (aspect_ratio == 0) {
691 		if (revision < 3)
692 			vsize = hsize;
693 		else
694 			vsize = (hsize * 10) / 16;
695 	} else if (aspect_ratio == 1)
696 		vsize = (hsize * 3) / 4;
697 	else if (aspect_ratio == 2)
698 		vsize = (hsize * 4) / 5;
699 	else
700 		vsize = (hsize * 9) / 16;
701 
702 	/* HDTV hack, part 1 */
703 	if (vrefresh_rate == 60 &&
704 	    ((hsize == 1360 && vsize == 765) ||
705 	     (hsize == 1368 && vsize == 769))) {
706 		hsize = 1366;
707 		vsize = 768;
708 	}
709 
710 	/*
711 	 * If this connector already has a mode for this size and refresh
712 	 * rate (because it came from detailed or CVT info), use that
713 	 * instead.  This way we don't have to guess at interlace or
714 	 * reduced blanking.
715 	 */
716 	list_for_each_entry(m, &connector->probed_modes, head)
717 		if (m->hdisplay == hsize && m->vdisplay == vsize &&
718 		    drm_mode_vrefresh(m) == vrefresh_rate)
719 			return NULL;
720 
721 	/* HDTV hack, part 2 */
722 	if (hsize == 1366 && vsize == 768 && vrefresh_rate == 60) {
723 		mode = drm_cvt_mode(dev, 1366, 768, vrefresh_rate, 0, 0,
724 				    false);
725 		mode->hdisplay = 1366;
726 		mode->hsync_start = mode->hsync_start - 1;
727 		mode->hsync_end = mode->hsync_end - 1;
728 		return mode;
729 	}
730 
731 	/* check whether it can be found in default mode table */
732 	mode = drm_mode_find_dmt(dev, hsize, vsize, vrefresh_rate);
733 	if (mode)
734 		return mode;
735 
736 	switch (timing_level) {
737 	case LEVEL_DMT:
738 		break;
739 	case LEVEL_GTF:
740 		mode = drm_gtf_mode(dev, hsize, vsize, vrefresh_rate, 0, 0);
741 		break;
742 	case LEVEL_GTF2:
743 		/*
744 		 * This is potentially wrong if there's ever a monitor with
745 		 * more than one ranges section, each claiming a different
746 		 * secondary GTF curve.  Please don't do that.
747 		 */
748 		mode = drm_gtf_mode(dev, hsize, vsize, vrefresh_rate, 0, 0);
749 		if (drm_mode_hsync(mode) > drm_gtf2_hbreak(edid)) {
750 			kfree(mode);
751 			mode = drm_gtf_mode_complex(dev, hsize, vsize,
752 						    vrefresh_rate, 0, 0,
753 						    drm_gtf2_m(edid),
754 						    drm_gtf2_2c(edid),
755 						    drm_gtf2_k(edid),
756 						    drm_gtf2_2j(edid));
757 		}
758 		break;
759 	case LEVEL_CVT:
760 		mode = drm_cvt_mode(dev, hsize, vsize, vrefresh_rate, 0, 0,
761 				    false);
762 		break;
763 	}
764 	return mode;
765 }
766 
767 /*
768  * EDID is delightfully ambiguous about how interlaced modes are to be
769  * encoded.  Our internal representation is of frame height, but some
770  * HDTV detailed timings are encoded as field height.
771  *
772  * The format list here is from CEA, in frame size.  Technically we
773  * should be checking refresh rate too.  Whatever.
774  */
775 static void
776 drm_mode_do_interlace_quirk(struct drm_display_mode *mode,
777 			    struct detailed_pixel_timing *pt)
778 {
779 	int i;
780 	static const struct {
781 		int w, h;
782 	} cea_interlaced[] = {
783 		{ 1920, 1080 },
784 		{  720,  480 },
785 		{ 1440,  480 },
786 		{ 2880,  480 },
787 		{  720,  576 },
788 		{ 1440,  576 },
789 		{ 2880,  576 },
790 	};
791 
792 	if (!(pt->misc & DRM_EDID_PT_INTERLACED))
793 		return;
794 
795 	for (i = 0; i < ARRAY_SIZE(cea_interlaced); i++) {
796 		if ((mode->hdisplay == cea_interlaced[i].w) &&
797 		    (mode->vdisplay == cea_interlaced[i].h / 2)) {
798 			mode->vdisplay *= 2;
799 			mode->vsync_start *= 2;
800 			mode->vsync_end *= 2;
801 			mode->vtotal *= 2;
802 			mode->vtotal |= 1;
803 		}
804 	}
805 
806 	mode->flags |= DRM_MODE_FLAG_INTERLACE;
807 }
808 
809 /**
810  * drm_mode_detailed - create a new mode from an EDID detailed timing section
811  * @dev: DRM device (needed to create new mode)
812  * @edid: EDID block
813  * @timing: EDID detailed timing info
814  * @quirks: quirks to apply
815  *
816  * An EDID detailed timing block contains enough info for us to create and
817  * return a new struct drm_display_mode.
818  */
819 static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
820 						  struct edid *edid,
821 						  struct detailed_timing *timing,
822 						  u32 quirks)
823 {
824 	struct drm_display_mode *mode;
825 	struct detailed_pixel_timing *pt = &timing->data.pixel_data;
826 	unsigned hactive = (pt->hactive_hblank_hi & 0xf0) << 4 | pt->hactive_lo;
827 	unsigned vactive = (pt->vactive_vblank_hi & 0xf0) << 4 | pt->vactive_lo;
828 	unsigned hblank = (pt->hactive_hblank_hi & 0xf) << 8 | pt->hblank_lo;
829 	unsigned vblank = (pt->vactive_vblank_hi & 0xf) << 8 | pt->vblank_lo;
830 	unsigned hsync_offset = (pt->hsync_vsync_offset_pulse_width_hi & 0xc0) << 2 | pt->hsync_offset_lo;
831 	unsigned hsync_pulse_width = (pt->hsync_vsync_offset_pulse_width_hi & 0x30) << 4 | pt->hsync_pulse_width_lo;
832 	unsigned vsync_offset = (pt->hsync_vsync_offset_pulse_width_hi & 0xc) >> 2 | pt->vsync_offset_pulse_width_lo >> 4;
833 	unsigned vsync_pulse_width = (pt->hsync_vsync_offset_pulse_width_hi & 0x3) << 4 | (pt->vsync_offset_pulse_width_lo & 0xf);
834 
835 	/* ignore tiny modes */
836 	if (hactive < 64 || vactive < 64)
837 		return NULL;
838 
839 	if (pt->misc & DRM_EDID_PT_STEREO) {
840 		printk(KERN_WARNING "stereo mode not supported\n");
841 		return NULL;
842 	}
843 	if (!(pt->misc & DRM_EDID_PT_SEPARATE_SYNC)) {
844 		printk(KERN_WARNING "composite sync not supported\n");
845 	}
846 
847 	/* it is incorrect if hsync/vsync width is zero */
848 	if (!hsync_pulse_width || !vsync_pulse_width) {
849 		DRM_DEBUG_KMS("Incorrect Detailed timing. "
850 				"Wrong Hsync/Vsync pulse width\n");
851 		return NULL;
852 	}
853 	mode = drm_mode_create(dev);
854 	if (!mode)
855 		return NULL;
856 
857 	mode->type = DRM_MODE_TYPE_DRIVER;
858 
859 	if (quirks & EDID_QUIRK_135_CLOCK_TOO_HIGH)
860 		timing->pixel_clock = cpu_to_le16(1088);
861 
862 	mode->clock = le16_to_cpu(timing->pixel_clock) * 10;
863 
864 	mode->hdisplay = hactive;
865 	mode->hsync_start = mode->hdisplay + hsync_offset;
866 	mode->hsync_end = mode->hsync_start + hsync_pulse_width;
867 	mode->htotal = mode->hdisplay + hblank;
868 
869 	mode->vdisplay = vactive;
870 	mode->vsync_start = mode->vdisplay + vsync_offset;
871 	mode->vsync_end = mode->vsync_start + vsync_pulse_width;
872 	mode->vtotal = mode->vdisplay + vblank;
873 
874 	/* Some EDIDs have bogus h/vtotal values */
875 	if (mode->hsync_end > mode->htotal)
876 		mode->htotal = mode->hsync_end + 1;
877 	if (mode->vsync_end > mode->vtotal)
878 		mode->vtotal = mode->vsync_end + 1;
879 
880 	drm_mode_do_interlace_quirk(mode, pt);
881 
882 	drm_mode_set_name(mode);
883 
884 	if (quirks & EDID_QUIRK_DETAILED_SYNC_PP) {
885 		pt->misc |= DRM_EDID_PT_HSYNC_POSITIVE | DRM_EDID_PT_VSYNC_POSITIVE;
886 	}
887 
888 	mode->flags |= (pt->misc & DRM_EDID_PT_HSYNC_POSITIVE) ?
889 		DRM_MODE_FLAG_PHSYNC : DRM_MODE_FLAG_NHSYNC;
890 	mode->flags |= (pt->misc & DRM_EDID_PT_VSYNC_POSITIVE) ?
891 		DRM_MODE_FLAG_PVSYNC : DRM_MODE_FLAG_NVSYNC;
892 
893 	mode->width_mm = pt->width_mm_lo | (pt->width_height_mm_hi & 0xf0) << 4;
894 	mode->height_mm = pt->height_mm_lo | (pt->width_height_mm_hi & 0xf) << 8;
895 
896 	if (quirks & EDID_QUIRK_DETAILED_IN_CM) {
897 		mode->width_mm *= 10;
898 		mode->height_mm *= 10;
899 	}
900 
901 	if (quirks & EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE) {
902 		mode->width_mm = edid->width_cm * 10;
903 		mode->height_mm = edid->height_cm * 10;
904 	}
905 
906 	return mode;
907 }
908 
909 static bool
910 mode_is_rb(const struct drm_display_mode *mode)
911 {
912 	return (mode->htotal - mode->hdisplay == 160) &&
913 	       (mode->hsync_end - mode->hdisplay == 80) &&
914 	       (mode->hsync_end - mode->hsync_start == 32) &&
915 	       (mode->vsync_start - mode->vdisplay == 3);
916 }
917 
918 static bool
919 mode_in_hsync_range(const struct drm_display_mode *mode,
920 		    struct edid *edid, u8 *t)
921 {
922 	int hsync, hmin, hmax;
923 
924 	hmin = t[7];
925 	if (edid->revision >= 4)
926 	    hmin += ((t[4] & 0x04) ? 255 : 0);
927 	hmax = t[8];
928 	if (edid->revision >= 4)
929 	    hmax += ((t[4] & 0x08) ? 255 : 0);
930 	hsync = drm_mode_hsync(mode);
931 
932 	return (hsync <= hmax && hsync >= hmin);
933 }
934 
935 static bool
936 mode_in_vsync_range(const struct drm_display_mode *mode,
937 		    struct edid *edid, u8 *t)
938 {
939 	int vsync, vmin, vmax;
940 
941 	vmin = t[5];
942 	if (edid->revision >= 4)
943 	    vmin += ((t[4] & 0x01) ? 255 : 0);
944 	vmax = t[6];
945 	if (edid->revision >= 4)
946 	    vmax += ((t[4] & 0x02) ? 255 : 0);
947 	vsync = drm_mode_vrefresh(mode);
948 
949 	return (vsync <= vmax && vsync >= vmin);
950 }
951 
952 static u32
953 range_pixel_clock(struct edid *edid, u8 *t)
954 {
955 	/* unspecified */
956 	if (t[9] == 0 || t[9] == 255)
957 		return 0;
958 
959 	/* 1.4 with CVT support gives us real precision, yay */
960 	if (edid->revision >= 4 && t[10] == 0x04)
961 		return (t[9] * 10000) - ((t[12] >> 2) * 250);
962 
963 	/* 1.3 is pathetic, so fuzz up a bit */
964 	return t[9] * 10000 + 5001;
965 }
966 
967 static bool
968 mode_in_range(const struct drm_display_mode *mode, struct edid *edid,
969 	      struct detailed_timing *timing)
970 {
971 	u32 max_clock;
972 	u8 *t = (u8 *)timing;
973 
974 	if (!mode_in_hsync_range(mode, edid, t))
975 		return false;
976 
977 	if (!mode_in_vsync_range(mode, edid, t))
978 		return false;
979 
980 	if ((max_clock = range_pixel_clock(edid, t)))
981 		if (mode->clock > max_clock)
982 			return false;
983 
984 	/* 1.4 max horizontal check */
985 	if (edid->revision >= 4 && t[10] == 0x04)
986 		if (t[13] && mode->hdisplay > 8 * (t[13] + (256 * (t[12]&0x3))))
987 			return false;
988 
989 	if (mode_is_rb(mode) && !drm_monitor_supports_rb(edid))
990 		return false;
991 
992 	return true;
993 }
994 
995 /*
996  * XXX If drm_dmt_modes ever regrows the CVT-R modes (and it will) this will
997  * need to account for them.
998  */
999 static int
1000 drm_gtf_modes_for_range(struct drm_connector *connector, struct edid *edid,
1001 			struct detailed_timing *timing)
1002 {
1003 	int i, modes = 0;
1004 	struct drm_display_mode *newmode;
1005 	struct drm_device *dev = connector->dev;
1006 
1007 	for (i = 0; i < drm_num_dmt_modes; i++) {
1008 		if (mode_in_range(drm_dmt_modes + i, edid, timing)) {
1009 			newmode = drm_mode_duplicate(dev, &drm_dmt_modes[i]);
1010 			if (newmode) {
1011 				drm_mode_probed_add(connector, newmode);
1012 				modes++;
1013 			}
1014 		}
1015 	}
1016 
1017 	return modes;
1018 }
1019 
1020 static void
1021 do_inferred_modes(struct detailed_timing *timing, void *c)
1022 {
1023 	struct detailed_mode_closure *closure = c;
1024 	struct detailed_non_pixel *data = &timing->data.other_data;
1025 	int gtf = (closure->edid->features & DRM_EDID_FEATURE_DEFAULT_GTF);
1026 
1027 	if (gtf && data->type == EDID_DETAIL_MONITOR_RANGE)
1028 		closure->modes += drm_gtf_modes_for_range(closure->connector,
1029 							  closure->edid,
1030 							  timing);
1031 }
1032 
1033 static int
1034 add_inferred_modes(struct drm_connector *connector, struct edid *edid)
1035 {
1036 	struct detailed_mode_closure closure = {
1037 		connector, edid, 0, 0, 0
1038 	};
1039 
1040 	if (version_greater(edid, 1, 0))
1041 		drm_for_each_detailed_block((u8 *)edid, do_inferred_modes,
1042 					    &closure);
1043 
1044 	return closure.modes;
1045 }
1046 
1047 static int
1048 drm_est3_modes(struct drm_connector *connector, struct detailed_timing *timing)
1049 {
1050 	int i, j, m, modes = 0;
1051 	struct drm_display_mode *mode;
1052 	u8 *est = ((u8 *)timing) + 5;
1053 
1054 	for (i = 0; i < 6; i++) {
1055 		for (j = 7; j > 0; j--) {
1056 			m = (i * 8) + (7 - j);
1057 			if (m >= ARRAY_SIZE(est3_modes))
1058 				break;
1059 			if (est[i] & (1 << j)) {
1060 				mode = drm_mode_find_dmt(connector->dev,
1061 							 est3_modes[m].w,
1062 							 est3_modes[m].h,
1063 							 est3_modes[m].r
1064 							 /*, est3_modes[m].rb */);
1065 				if (mode) {
1066 					drm_mode_probed_add(connector, mode);
1067 					modes++;
1068 				}
1069 			}
1070 		}
1071 	}
1072 
1073 	return modes;
1074 }
1075 
1076 static void
1077 do_established_modes(struct detailed_timing *timing, void *c)
1078 {
1079 	struct detailed_mode_closure *closure = c;
1080 	struct detailed_non_pixel *data = &timing->data.other_data;
1081 
1082 	if (data->type == EDID_DETAIL_EST_TIMINGS)
1083 		closure->modes += drm_est3_modes(closure->connector, timing);
1084 }
1085 
1086 /**
1087  * add_established_modes - get est. modes from EDID and add them
1088  * @edid: EDID block to scan
1089  *
1090  * Each EDID block contains a bitmap of the supported "established modes" list
1091  * (defined above).  Tease them out and add them to the global modes list.
1092  */
1093 static int
1094 add_established_modes(struct drm_connector *connector, struct edid *edid)
1095 {
1096 	struct drm_device *dev = connector->dev;
1097 	unsigned long est_bits = edid->established_timings.t1 |
1098 		(edid->established_timings.t2 << 8) |
1099 		((edid->established_timings.mfg_rsvd & 0x80) << 9);
1100 	int i, modes = 0;
1101 	struct detailed_mode_closure closure = {
1102 		connector, edid, 0, 0, 0
1103 	};
1104 
1105 	for (i = 0; i <= EDID_EST_TIMINGS; i++) {
1106 		if (est_bits & (1<<i)) {
1107 			struct drm_display_mode *newmode;
1108 			newmode = drm_mode_duplicate(dev, &edid_est_modes[i]);
1109 			if (newmode) {
1110 				drm_mode_probed_add(connector, newmode);
1111 				modes++;
1112 			}
1113 		}
1114 	}
1115 
1116 	if (version_greater(edid, 1, 0))
1117 		    drm_for_each_detailed_block((u8 *)edid,
1118 						do_established_modes, &closure);
1119 
1120 	return modes + closure.modes;
1121 }
1122 
1123 static void
1124 do_standard_modes(struct detailed_timing *timing, void *c)
1125 {
1126 	struct detailed_mode_closure *closure = c;
1127 	struct detailed_non_pixel *data = &timing->data.other_data;
1128 	struct drm_connector *connector = closure->connector;
1129 	struct edid *edid = closure->edid;
1130 
1131 	if (data->type == EDID_DETAIL_STD_MODES) {
1132 		int i;
1133 		for (i = 0; i < 6; i++) {
1134 			struct std_timing *std;
1135 			struct drm_display_mode *newmode;
1136 
1137 			std = &data->data.timings[i];
1138 			newmode = drm_mode_std(connector, edid, std,
1139 					       edid->revision);
1140 			if (newmode) {
1141 				drm_mode_probed_add(connector, newmode);
1142 				closure->modes++;
1143 			}
1144 		}
1145 	}
1146 }
1147 
1148 /**
1149  * add_standard_modes - get std. modes from EDID and add them
1150  * @edid: EDID block to scan
1151  *
1152  * Standard modes can be calculated using the appropriate standard (DMT,
1153  * GTF or CVT. Grab them from @edid and add them to the list.
1154  */
1155 static int
1156 add_standard_modes(struct drm_connector *connector, struct edid *edid)
1157 {
1158 	int i, modes = 0;
1159 	struct detailed_mode_closure closure = {
1160 		connector, edid, 0, 0, 0
1161 	};
1162 
1163 	for (i = 0; i < EDID_STD_TIMINGS; i++) {
1164 		struct drm_display_mode *newmode;
1165 
1166 		newmode = drm_mode_std(connector, edid,
1167 				       &edid->standard_timings[i],
1168 				       edid->revision);
1169 		if (newmode) {
1170 			drm_mode_probed_add(connector, newmode);
1171 			modes++;
1172 		}
1173 	}
1174 
1175 	if (version_greater(edid, 1, 0))
1176 		drm_for_each_detailed_block((u8 *)edid, do_standard_modes,
1177 					    &closure);
1178 
1179 	/* XXX should also look for standard codes in VTB blocks */
1180 
1181 	return modes + closure.modes;
1182 }
1183 
1184 static int drm_cvt_modes(struct drm_connector *connector,
1185 			 struct detailed_timing *timing)
1186 {
1187 	int i, j, modes = 0;
1188 	struct drm_display_mode *newmode;
1189 	struct drm_device *dev = connector->dev;
1190 	struct cvt_timing *cvt;
1191 	const int rates[] = { 60, 85, 75, 60, 50 };
1192 	const u8 empty[3] = { 0, 0, 0 };
1193 
1194 	for (i = 0; i < 4; i++) {
1195 		int uninitialized_var(width), height;
1196 		cvt = &(timing->data.other_data.data.cvt[i]);
1197 
1198 		if (!memcmp(cvt->code, empty, 3))
1199 			continue;
1200 
1201 		height = (cvt->code[0] + ((cvt->code[1] & 0xf0) << 4) + 1) * 2;
1202 		switch (cvt->code[1] & 0x0c) {
1203 		case 0x00:
1204 			width = height * 4 / 3;
1205 			break;
1206 		case 0x04:
1207 			width = height * 16 / 9;
1208 			break;
1209 		case 0x08:
1210 			width = height * 16 / 10;
1211 			break;
1212 		case 0x0c:
1213 			width = height * 15 / 9;
1214 			break;
1215 		}
1216 
1217 		for (j = 1; j < 5; j++) {
1218 			if (cvt->code[2] & (1 << j)) {
1219 				newmode = drm_cvt_mode(dev, width, height,
1220 						       rates[j], j == 0,
1221 						       false, false);
1222 				if (newmode) {
1223 					drm_mode_probed_add(connector, newmode);
1224 					modes++;
1225 				}
1226 			}
1227 		}
1228 	}
1229 
1230 	return modes;
1231 }
1232 
1233 static void
1234 do_cvt_mode(struct detailed_timing *timing, void *c)
1235 {
1236 	struct detailed_mode_closure *closure = c;
1237 	struct detailed_non_pixel *data = &timing->data.other_data;
1238 
1239 	if (data->type == EDID_DETAIL_CVT_3BYTE)
1240 		closure->modes += drm_cvt_modes(closure->connector, timing);
1241 }
1242 
1243 static int
1244 add_cvt_modes(struct drm_connector *connector, struct edid *edid)
1245 {
1246 	struct detailed_mode_closure closure = {
1247 		connector, edid, 0, 0, 0
1248 	};
1249 
1250 	if (version_greater(edid, 1, 2))
1251 		drm_for_each_detailed_block((u8 *)edid, do_cvt_mode, &closure);
1252 
1253 	/* XXX should also look for CVT codes in VTB blocks */
1254 
1255 	return closure.modes;
1256 }
1257 
1258 static void
1259 do_detailed_mode(struct detailed_timing *timing, void *c)
1260 {
1261 	struct detailed_mode_closure *closure = c;
1262 	struct drm_display_mode *newmode;
1263 
1264 	if (timing->pixel_clock) {
1265 		newmode = drm_mode_detailed(closure->connector->dev,
1266 					    closure->edid, timing,
1267 					    closure->quirks);
1268 		if (!newmode)
1269 			return;
1270 
1271 		if (closure->preferred)
1272 			newmode->type |= DRM_MODE_TYPE_PREFERRED;
1273 
1274 		drm_mode_probed_add(closure->connector, newmode);
1275 		closure->modes++;
1276 		closure->preferred = 0;
1277 	}
1278 }
1279 
1280 /*
1281  * add_detailed_modes - Add modes from detailed timings
1282  * @connector: attached connector
1283  * @edid: EDID block to scan
1284  * @quirks: quirks to apply
1285  */
1286 static int
1287 add_detailed_modes(struct drm_connector *connector, struct edid *edid,
1288 		   u32 quirks)
1289 {
1290 	struct detailed_mode_closure closure = {
1291 		connector,
1292 		edid,
1293 		1,
1294 		quirks,
1295 		0
1296 	};
1297 
1298 	if (closure.preferred && !version_greater(edid, 1, 3))
1299 		closure.preferred =
1300 		    (edid->features & DRM_EDID_FEATURE_PREFERRED_TIMING);
1301 
1302 	drm_for_each_detailed_block((u8 *)edid, do_detailed_mode, &closure);
1303 
1304 	return closure.modes;
1305 }
1306 
1307 #define HDMI_IDENTIFIER 0x000C03
1308 #define AUDIO_BLOCK	0x01
1309 #define VENDOR_BLOCK    0x03
1310 #define EDID_BASIC_AUDIO	(1 << 6)
1311 
1312 /**
1313  * Search EDID for CEA extension block.
1314  */
1315 u8 *drm_find_cea_extension(struct edid *edid)
1316 {
1317 	u8 *edid_ext = NULL;
1318 	int i;
1319 
1320 	/* No EDID or EDID extensions */
1321 	if (edid == NULL || edid->extensions == 0)
1322 		return NULL;
1323 
1324 	/* Find CEA extension */
1325 	for (i = 0; i < edid->extensions; i++) {
1326 		edid_ext = (u8 *)edid + EDID_LENGTH * (i + 1);
1327 		if (edid_ext[0] == CEA_EXT)
1328 			break;
1329 	}
1330 
1331 	if (i == edid->extensions)
1332 		return NULL;
1333 
1334 	return edid_ext;
1335 }
1336 EXPORT_SYMBOL(drm_find_cea_extension);
1337 
1338 /**
1339  * drm_detect_hdmi_monitor - detect whether monitor is hdmi.
1340  * @edid: monitor EDID information
1341  *
1342  * Parse the CEA extension according to CEA-861-B.
1343  * Return true if HDMI, false if not or unknown.
1344  */
1345 bool drm_detect_hdmi_monitor(struct edid *edid)
1346 {
1347 	u8 *edid_ext;
1348 	int i, hdmi_id;
1349 	int start_offset, end_offset;
1350 	bool is_hdmi = false;
1351 
1352 	edid_ext = drm_find_cea_extension(edid);
1353 	if (!edid_ext)
1354 		goto end;
1355 
1356 	/* Data block offset in CEA extension block */
1357 	start_offset = 4;
1358 	end_offset = edid_ext[2];
1359 
1360 	/*
1361 	 * Because HDMI identifier is in Vendor Specific Block,
1362 	 * search it from all data blocks of CEA extension.
1363 	 */
1364 	for (i = start_offset; i < end_offset;
1365 		/* Increased by data block len */
1366 		i += ((edid_ext[i] & 0x1f) + 1)) {
1367 		/* Find vendor specific block */
1368 		if ((edid_ext[i] >> 5) == VENDOR_BLOCK) {
1369 			hdmi_id = edid_ext[i + 1] | (edid_ext[i + 2] << 8) |
1370 				  edid_ext[i + 3] << 16;
1371 			/* Find HDMI identifier */
1372 			if (hdmi_id == HDMI_IDENTIFIER)
1373 				is_hdmi = true;
1374 			break;
1375 		}
1376 	}
1377 
1378 end:
1379 	return is_hdmi;
1380 }
1381 EXPORT_SYMBOL(drm_detect_hdmi_monitor);
1382 
1383 /**
1384  * drm_detect_monitor_audio - check monitor audio capability
1385  *
1386  * Monitor should have CEA extension block.
1387  * If monitor has 'basic audio', but no CEA audio blocks, it's 'basic
1388  * audio' only. If there is any audio extension block and supported
1389  * audio format, assume at least 'basic audio' support, even if 'basic
1390  * audio' is not defined in EDID.
1391  *
1392  */
1393 bool drm_detect_monitor_audio(struct edid *edid)
1394 {
1395 	u8 *edid_ext;
1396 	int i, j;
1397 	bool has_audio = false;
1398 	int start_offset, end_offset;
1399 
1400 	edid_ext = drm_find_cea_extension(edid);
1401 	if (!edid_ext)
1402 		goto end;
1403 
1404 	has_audio = ((edid_ext[3] & EDID_BASIC_AUDIO) != 0);
1405 
1406 	if (has_audio) {
1407 		DRM_DEBUG_KMS("Monitor has basic audio support\n");
1408 		goto end;
1409 	}
1410 
1411 	/* Data block offset in CEA extension block */
1412 	start_offset = 4;
1413 	end_offset = edid_ext[2];
1414 
1415 	for (i = start_offset; i < end_offset;
1416 			i += ((edid_ext[i] & 0x1f) + 1)) {
1417 		if ((edid_ext[i] >> 5) == AUDIO_BLOCK) {
1418 			has_audio = true;
1419 			for (j = 1; j < (edid_ext[i] & 0x1f); j += 3)
1420 				DRM_DEBUG_KMS("CEA audio format %d\n",
1421 					      (edid_ext[i + j] >> 3) & 0xf);
1422 			goto end;
1423 		}
1424 	}
1425 end:
1426 	return has_audio;
1427 }
1428 EXPORT_SYMBOL(drm_detect_monitor_audio);
1429 
1430 /**
1431  * drm_add_display_info - pull display info out if present
1432  * @edid: EDID data
1433  * @info: display info (attached to connector)
1434  *
1435  * Grab any available display info and stuff it into the drm_display_info
1436  * structure that's part of the connector.  Useful for tracking bpp and
1437  * color spaces.
1438  */
1439 static void drm_add_display_info(struct edid *edid,
1440 				 struct drm_display_info *info)
1441 {
1442 	info->width_mm = edid->width_cm * 10;
1443 	info->height_mm = edid->height_cm * 10;
1444 
1445 	/* driver figures it out in this case */
1446 	info->bpc = 0;
1447 	info->color_formats = 0;
1448 
1449 	/* Only defined for 1.4 with digital displays */
1450 	if (edid->revision < 4)
1451 		return;
1452 
1453 	if (!(edid->input & DRM_EDID_INPUT_DIGITAL))
1454 		return;
1455 
1456 	switch (edid->input & DRM_EDID_DIGITAL_DEPTH_MASK) {
1457 	case DRM_EDID_DIGITAL_DEPTH_6:
1458 		info->bpc = 6;
1459 		break;
1460 	case DRM_EDID_DIGITAL_DEPTH_8:
1461 		info->bpc = 8;
1462 		break;
1463 	case DRM_EDID_DIGITAL_DEPTH_10:
1464 		info->bpc = 10;
1465 		break;
1466 	case DRM_EDID_DIGITAL_DEPTH_12:
1467 		info->bpc = 12;
1468 		break;
1469 	case DRM_EDID_DIGITAL_DEPTH_14:
1470 		info->bpc = 14;
1471 		break;
1472 	case DRM_EDID_DIGITAL_DEPTH_16:
1473 		info->bpc = 16;
1474 		break;
1475 	case DRM_EDID_DIGITAL_DEPTH_UNDEF:
1476 	default:
1477 		info->bpc = 0;
1478 		break;
1479 	}
1480 
1481 	info->color_formats = DRM_COLOR_FORMAT_RGB444;
1482 	if (info->color_formats & DRM_EDID_FEATURE_RGB_YCRCB444)
1483 		info->color_formats = DRM_COLOR_FORMAT_YCRCB444;
1484 	if (info->color_formats & DRM_EDID_FEATURE_RGB_YCRCB422)
1485 		info->color_formats = DRM_COLOR_FORMAT_YCRCB422;
1486 }
1487 
1488 /**
1489  * drm_add_edid_modes - add modes from EDID data, if available
1490  * @connector: connector we're probing
1491  * @edid: edid data
1492  *
1493  * Add the specified modes to the connector's mode list.
1494  *
1495  * Return number of modes added or 0 if we couldn't find any.
1496  */
1497 int drm_add_edid_modes(struct drm_connector *connector, struct edid *edid)
1498 {
1499 	int num_modes = 0;
1500 	u32 quirks;
1501 
1502 	if (edid == NULL) {
1503 		return 0;
1504 	}
1505 	if (!drm_edid_is_valid(edid)) {
1506 		dev_warn(connector->dev->dev, "%s: EDID invalid.\n",
1507 			 drm_get_connector_name(connector));
1508 		return 0;
1509 	}
1510 
1511 	quirks = edid_get_quirks(edid);
1512 
1513 	/*
1514 	 * EDID spec says modes should be preferred in this order:
1515 	 * - preferred detailed mode
1516 	 * - other detailed modes from base block
1517 	 * - detailed modes from extension blocks
1518 	 * - CVT 3-byte code modes
1519 	 * - standard timing codes
1520 	 * - established timing codes
1521 	 * - modes inferred from GTF or CVT range information
1522 	 *
1523 	 * We get this pretty much right.
1524 	 *
1525 	 * XXX order for additional mode types in extension blocks?
1526 	 */
1527 	num_modes += add_detailed_modes(connector, edid, quirks);
1528 	num_modes += add_cvt_modes(connector, edid);
1529 	num_modes += add_standard_modes(connector, edid);
1530 	num_modes += add_established_modes(connector, edid);
1531 	num_modes += add_inferred_modes(connector, edid);
1532 
1533 	if (quirks & (EDID_QUIRK_PREFER_LARGE_60 | EDID_QUIRK_PREFER_LARGE_75))
1534 		edid_fixup_preferred(connector, quirks);
1535 
1536 	drm_add_display_info(edid, &connector->display_info);
1537 
1538 	return num_modes;
1539 }
1540 EXPORT_SYMBOL(drm_add_edid_modes);
1541 
1542 /**
1543  * drm_add_modes_noedid - add modes for the connectors without EDID
1544  * @connector: connector we're probing
1545  * @hdisplay: the horizontal display limit
1546  * @vdisplay: the vertical display limit
1547  *
1548  * Add the specified modes to the connector's mode list. Only when the
1549  * hdisplay/vdisplay is not beyond the given limit, it will be added.
1550  *
1551  * Return number of modes added or 0 if we couldn't find any.
1552  */
1553 int drm_add_modes_noedid(struct drm_connector *connector,
1554 			int hdisplay, int vdisplay)
1555 {
1556 	int i, count, num_modes = 0;
1557 	struct drm_display_mode *mode;
1558 	struct drm_device *dev = connector->dev;
1559 
1560 	count = sizeof(drm_dmt_modes) / sizeof(struct drm_display_mode);
1561 	if (hdisplay < 0)
1562 		hdisplay = 0;
1563 	if (vdisplay < 0)
1564 		vdisplay = 0;
1565 
1566 	for (i = 0; i < count; i++) {
1567 		const struct drm_display_mode *ptr = &drm_dmt_modes[i];
1568 		if (hdisplay && vdisplay) {
1569 			/*
1570 			 * Only when two are valid, they will be used to check
1571 			 * whether the mode should be added to the mode list of
1572 			 * the connector.
1573 			 */
1574 			if (ptr->hdisplay > hdisplay ||
1575 					ptr->vdisplay > vdisplay)
1576 				continue;
1577 		}
1578 		if (drm_mode_vrefresh(ptr) > 61)
1579 			continue;
1580 		mode = drm_mode_duplicate(dev, ptr);
1581 		if (mode) {
1582 			drm_mode_probed_add(connector, mode);
1583 			num_modes++;
1584 		}
1585 	}
1586 	return num_modes;
1587 }
1588 EXPORT_SYMBOL(drm_add_modes_noedid);
1589