xref: /linux/drivers/gpu/drm/drm_modes.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Copyright © 1997-2003 by The XFree86 Project, Inc.
3  * Copyright © 2007 Dave Airlie
4  * Copyright © 2007-2008 Intel Corporation
5  *   Jesse Barnes <jesse.barnes@intel.com>
6  * Copyright 2005-2006 Luc Verhaegen
7  * Copyright (c) 2001, Andy Ritger  aritger@nvidia.com
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a
10  * copy of this software and associated documentation files (the "Software"),
11  * to deal in the Software without restriction, including without limitation
12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13  * and/or sell copies of the Software, and to permit persons to whom the
14  * Software is furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
22  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
25  * OTHER DEALINGS IN THE SOFTWARE.
26  *
27  * Except as contained in this notice, the name of the copyright holder(s)
28  * and author(s) shall not be used in advertising or otherwise to promote
29  * the sale, use or other dealings in this Software without prior written
30  * authorization from the copyright holder(s) and author(s).
31  */
32 
33 #include <linux/list.h>
34 #include <linux/list_sort.h>
35 #include <linux/export.h>
36 #include <drm/drmP.h>
37 #include <drm/drm_crtc.h>
38 #include <video/of_videomode.h>
39 #include <video/videomode.h>
40 #include <drm/drm_modes.h>
41 
42 #include "drm_crtc_internal.h"
43 
44 /**
45  * drm_mode_debug_printmodeline - print a mode to dmesg
46  * @mode: mode to print
47  *
48  * Describe @mode using DRM_DEBUG.
49  */
50 void drm_mode_debug_printmodeline(const struct drm_display_mode *mode)
51 {
52 	DRM_DEBUG_KMS("Modeline %d:\"%s\" %d %d %d %d %d %d %d %d %d %d "
53 			"0x%x 0x%x\n",
54 		mode->base.id, mode->name, mode->vrefresh, mode->clock,
55 		mode->hdisplay, mode->hsync_start,
56 		mode->hsync_end, mode->htotal,
57 		mode->vdisplay, mode->vsync_start,
58 		mode->vsync_end, mode->vtotal, mode->type, mode->flags);
59 }
60 EXPORT_SYMBOL(drm_mode_debug_printmodeline);
61 
62 /**
63  * drm_mode_create - create a new display mode
64  * @dev: DRM device
65  *
66  * Create a new, cleared drm_display_mode with kzalloc, allocate an ID for it
67  * and return it.
68  *
69  * Returns:
70  * Pointer to new mode on success, NULL on error.
71  */
72 struct drm_display_mode *drm_mode_create(struct drm_device *dev)
73 {
74 	struct drm_display_mode *nmode;
75 
76 	nmode = kzalloc(sizeof(struct drm_display_mode), GFP_KERNEL);
77 	if (!nmode)
78 		return NULL;
79 
80 	if (drm_mode_object_get(dev, &nmode->base, DRM_MODE_OBJECT_MODE)) {
81 		kfree(nmode);
82 		return NULL;
83 	}
84 
85 	return nmode;
86 }
87 EXPORT_SYMBOL(drm_mode_create);
88 
89 /**
90  * drm_mode_destroy - remove a mode
91  * @dev: DRM device
92  * @mode: mode to remove
93  *
94  * Release @mode's unique ID, then free it @mode structure itself using kfree.
95  */
96 void drm_mode_destroy(struct drm_device *dev, struct drm_display_mode *mode)
97 {
98 	if (!mode)
99 		return;
100 
101 	drm_mode_object_put(dev, &mode->base);
102 
103 	kfree(mode);
104 }
105 EXPORT_SYMBOL(drm_mode_destroy);
106 
107 /**
108  * drm_mode_probed_add - add a mode to a connector's probed_mode list
109  * @connector: connector the new mode
110  * @mode: mode data
111  *
112  * Add @mode to @connector's probed_mode list for later use. This list should
113  * then in a second step get filtered and all the modes actually supported by
114  * the hardware moved to the @connector's modes list.
115  */
116 void drm_mode_probed_add(struct drm_connector *connector,
117 			 struct drm_display_mode *mode)
118 {
119 	WARN_ON(!mutex_is_locked(&connector->dev->mode_config.mutex));
120 
121 	list_add_tail(&mode->head, &connector->probed_modes);
122 }
123 EXPORT_SYMBOL(drm_mode_probed_add);
124 
125 /**
126  * drm_cvt_mode -create a modeline based on the CVT algorithm
127  * @dev: drm device
128  * @hdisplay: hdisplay size
129  * @vdisplay: vdisplay size
130  * @vrefresh: vrefresh rate
131  * @reduced: whether to use reduced blanking
132  * @interlaced: whether to compute an interlaced mode
133  * @margins: whether to add margins (borders)
134  *
135  * This function is called to generate the modeline based on CVT algorithm
136  * according to the hdisplay, vdisplay, vrefresh.
137  * It is based from the VESA(TM) Coordinated Video Timing Generator by
138  * Graham Loveridge April 9, 2003 available at
139  * http://www.elo.utfsm.cl/~elo212/docs/CVTd6r1.xls
140  *
141  * And it is copied from xf86CVTmode in xserver/hw/xfree86/modes/xf86cvt.c.
142  * What I have done is to translate it by using integer calculation.
143  *
144  * Returns:
145  * The modeline based on the CVT algorithm stored in a drm_display_mode object.
146  * The display mode object is allocated with drm_mode_create(). Returns NULL
147  * when no mode could be allocated.
148  */
149 struct drm_display_mode *drm_cvt_mode(struct drm_device *dev, int hdisplay,
150 				      int vdisplay, int vrefresh,
151 				      bool reduced, bool interlaced, bool margins)
152 {
153 #define HV_FACTOR			1000
154 	/* 1) top/bottom margin size (% of height) - default: 1.8, */
155 #define	CVT_MARGIN_PERCENTAGE		18
156 	/* 2) character cell horizontal granularity (pixels) - default 8 */
157 #define	CVT_H_GRANULARITY		8
158 	/* 3) Minimum vertical porch (lines) - default 3 */
159 #define	CVT_MIN_V_PORCH			3
160 	/* 4) Minimum number of vertical back porch lines - default 6 */
161 #define	CVT_MIN_V_BPORCH		6
162 	/* Pixel Clock step (kHz) */
163 #define CVT_CLOCK_STEP			250
164 	struct drm_display_mode *drm_mode;
165 	unsigned int vfieldrate, hperiod;
166 	int hdisplay_rnd, hmargin, vdisplay_rnd, vmargin, vsync;
167 	int interlace;
168 
169 	/* allocate the drm_display_mode structure. If failure, we will
170 	 * return directly
171 	 */
172 	drm_mode = drm_mode_create(dev);
173 	if (!drm_mode)
174 		return NULL;
175 
176 	/* the CVT default refresh rate is 60Hz */
177 	if (!vrefresh)
178 		vrefresh = 60;
179 
180 	/* the required field fresh rate */
181 	if (interlaced)
182 		vfieldrate = vrefresh * 2;
183 	else
184 		vfieldrate = vrefresh;
185 
186 	/* horizontal pixels */
187 	hdisplay_rnd = hdisplay - (hdisplay % CVT_H_GRANULARITY);
188 
189 	/* determine the left&right borders */
190 	hmargin = 0;
191 	if (margins) {
192 		hmargin = hdisplay_rnd * CVT_MARGIN_PERCENTAGE / 1000;
193 		hmargin -= hmargin % CVT_H_GRANULARITY;
194 	}
195 	/* find the total active pixels */
196 	drm_mode->hdisplay = hdisplay_rnd + 2 * hmargin;
197 
198 	/* find the number of lines per field */
199 	if (interlaced)
200 		vdisplay_rnd = vdisplay / 2;
201 	else
202 		vdisplay_rnd = vdisplay;
203 
204 	/* find the top & bottom borders */
205 	vmargin = 0;
206 	if (margins)
207 		vmargin = vdisplay_rnd * CVT_MARGIN_PERCENTAGE / 1000;
208 
209 	drm_mode->vdisplay = vdisplay + 2 * vmargin;
210 
211 	/* Interlaced */
212 	if (interlaced)
213 		interlace = 1;
214 	else
215 		interlace = 0;
216 
217 	/* Determine VSync Width from aspect ratio */
218 	if (!(vdisplay % 3) && ((vdisplay * 4 / 3) == hdisplay))
219 		vsync = 4;
220 	else if (!(vdisplay % 9) && ((vdisplay * 16 / 9) == hdisplay))
221 		vsync = 5;
222 	else if (!(vdisplay % 10) && ((vdisplay * 16 / 10) == hdisplay))
223 		vsync = 6;
224 	else if (!(vdisplay % 4) && ((vdisplay * 5 / 4) == hdisplay))
225 		vsync = 7;
226 	else if (!(vdisplay % 9) && ((vdisplay * 15 / 9) == hdisplay))
227 		vsync = 7;
228 	else /* custom */
229 		vsync = 10;
230 
231 	if (!reduced) {
232 		/* simplify the GTF calculation */
233 		/* 4) Minimum time of vertical sync + back porch interval (µs)
234 		 * default 550.0
235 		 */
236 		int tmp1, tmp2;
237 #define CVT_MIN_VSYNC_BP	550
238 		/* 3) Nominal HSync width (% of line period) - default 8 */
239 #define CVT_HSYNC_PERCENTAGE	8
240 		unsigned int hblank_percentage;
241 		int vsyncandback_porch, vback_porch, hblank;
242 
243 		/* estimated the horizontal period */
244 		tmp1 = HV_FACTOR * 1000000  -
245 				CVT_MIN_VSYNC_BP * HV_FACTOR * vfieldrate;
246 		tmp2 = (vdisplay_rnd + 2 * vmargin + CVT_MIN_V_PORCH) * 2 +
247 				interlace;
248 		hperiod = tmp1 * 2 / (tmp2 * vfieldrate);
249 
250 		tmp1 = CVT_MIN_VSYNC_BP * HV_FACTOR / hperiod + 1;
251 		/* 9. Find number of lines in sync + backporch */
252 		if (tmp1 < (vsync + CVT_MIN_V_PORCH))
253 			vsyncandback_porch = vsync + CVT_MIN_V_PORCH;
254 		else
255 			vsyncandback_porch = tmp1;
256 		/* 10. Find number of lines in back porch */
257 		vback_porch = vsyncandback_porch - vsync;
258 		drm_mode->vtotal = vdisplay_rnd + 2 * vmargin +
259 				vsyncandback_porch + CVT_MIN_V_PORCH;
260 		/* 5) Definition of Horizontal blanking time limitation */
261 		/* Gradient (%/kHz) - default 600 */
262 #define CVT_M_FACTOR	600
263 		/* Offset (%) - default 40 */
264 #define CVT_C_FACTOR	40
265 		/* Blanking time scaling factor - default 128 */
266 #define CVT_K_FACTOR	128
267 		/* Scaling factor weighting - default 20 */
268 #define CVT_J_FACTOR	20
269 #define CVT_M_PRIME	(CVT_M_FACTOR * CVT_K_FACTOR / 256)
270 #define CVT_C_PRIME	((CVT_C_FACTOR - CVT_J_FACTOR) * CVT_K_FACTOR / 256 + \
271 			 CVT_J_FACTOR)
272 		/* 12. Find ideal blanking duty cycle from formula */
273 		hblank_percentage = CVT_C_PRIME * HV_FACTOR - CVT_M_PRIME *
274 					hperiod / 1000;
275 		/* 13. Blanking time */
276 		if (hblank_percentage < 20 * HV_FACTOR)
277 			hblank_percentage = 20 * HV_FACTOR;
278 		hblank = drm_mode->hdisplay * hblank_percentage /
279 			 (100 * HV_FACTOR - hblank_percentage);
280 		hblank -= hblank % (2 * CVT_H_GRANULARITY);
281 		/* 14. find the total pixels per line */
282 		drm_mode->htotal = drm_mode->hdisplay + hblank;
283 		drm_mode->hsync_end = drm_mode->hdisplay + hblank / 2;
284 		drm_mode->hsync_start = drm_mode->hsync_end -
285 			(drm_mode->htotal * CVT_HSYNC_PERCENTAGE) / 100;
286 		drm_mode->hsync_start += CVT_H_GRANULARITY -
287 			drm_mode->hsync_start % CVT_H_GRANULARITY;
288 		/* fill the Vsync values */
289 		drm_mode->vsync_start = drm_mode->vdisplay + CVT_MIN_V_PORCH;
290 		drm_mode->vsync_end = drm_mode->vsync_start + vsync;
291 	} else {
292 		/* Reduced blanking */
293 		/* Minimum vertical blanking interval time (µs)- default 460 */
294 #define CVT_RB_MIN_VBLANK	460
295 		/* Fixed number of clocks for horizontal sync */
296 #define CVT_RB_H_SYNC		32
297 		/* Fixed number of clocks for horizontal blanking */
298 #define CVT_RB_H_BLANK		160
299 		/* Fixed number of lines for vertical front porch - default 3*/
300 #define CVT_RB_VFPORCH		3
301 		int vbilines;
302 		int tmp1, tmp2;
303 		/* 8. Estimate Horizontal period. */
304 		tmp1 = HV_FACTOR * 1000000 -
305 			CVT_RB_MIN_VBLANK * HV_FACTOR * vfieldrate;
306 		tmp2 = vdisplay_rnd + 2 * vmargin;
307 		hperiod = tmp1 / (tmp2 * vfieldrate);
308 		/* 9. Find number of lines in vertical blanking */
309 		vbilines = CVT_RB_MIN_VBLANK * HV_FACTOR / hperiod + 1;
310 		/* 10. Check if vertical blanking is sufficient */
311 		if (vbilines < (CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH))
312 			vbilines = CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH;
313 		/* 11. Find total number of lines in vertical field */
314 		drm_mode->vtotal = vdisplay_rnd + 2 * vmargin + vbilines;
315 		/* 12. Find total number of pixels in a line */
316 		drm_mode->htotal = drm_mode->hdisplay + CVT_RB_H_BLANK;
317 		/* Fill in HSync values */
318 		drm_mode->hsync_end = drm_mode->hdisplay + CVT_RB_H_BLANK / 2;
319 		drm_mode->hsync_start = drm_mode->hsync_end - CVT_RB_H_SYNC;
320 		/* Fill in VSync values */
321 		drm_mode->vsync_start = drm_mode->vdisplay + CVT_RB_VFPORCH;
322 		drm_mode->vsync_end = drm_mode->vsync_start + vsync;
323 	}
324 	/* 15/13. Find pixel clock frequency (kHz for xf86) */
325 	drm_mode->clock = drm_mode->htotal * HV_FACTOR * 1000 / hperiod;
326 	drm_mode->clock -= drm_mode->clock % CVT_CLOCK_STEP;
327 	/* 18/16. Find actual vertical frame frequency */
328 	/* ignore - just set the mode flag for interlaced */
329 	if (interlaced) {
330 		drm_mode->vtotal *= 2;
331 		drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
332 	}
333 	/* Fill the mode line name */
334 	drm_mode_set_name(drm_mode);
335 	if (reduced)
336 		drm_mode->flags |= (DRM_MODE_FLAG_PHSYNC |
337 					DRM_MODE_FLAG_NVSYNC);
338 	else
339 		drm_mode->flags |= (DRM_MODE_FLAG_PVSYNC |
340 					DRM_MODE_FLAG_NHSYNC);
341 
342 	return drm_mode;
343 }
344 EXPORT_SYMBOL(drm_cvt_mode);
345 
346 /**
347  * drm_gtf_mode_complex - create the modeline based on the full GTF algorithm
348  * @dev: drm device
349  * @hdisplay: hdisplay size
350  * @vdisplay: vdisplay size
351  * @vrefresh: vrefresh rate.
352  * @interlaced: whether to compute an interlaced mode
353  * @margins: desired margin (borders) size
354  * @GTF_M: extended GTF formula parameters
355  * @GTF_2C: extended GTF formula parameters
356  * @GTF_K: extended GTF formula parameters
357  * @GTF_2J: extended GTF formula parameters
358  *
359  * GTF feature blocks specify C and J in multiples of 0.5, so we pass them
360  * in here multiplied by two.  For a C of 40, pass in 80.
361  *
362  * Returns:
363  * The modeline based on the full GTF algorithm stored in a drm_display_mode object.
364  * The display mode object is allocated with drm_mode_create(). Returns NULL
365  * when no mode could be allocated.
366  */
367 struct drm_display_mode *
368 drm_gtf_mode_complex(struct drm_device *dev, int hdisplay, int vdisplay,
369 		     int vrefresh, bool interlaced, int margins,
370 		     int GTF_M, int GTF_2C, int GTF_K, int GTF_2J)
371 {	/* 1) top/bottom margin size (% of height) - default: 1.8, */
372 #define	GTF_MARGIN_PERCENTAGE		18
373 	/* 2) character cell horizontal granularity (pixels) - default 8 */
374 #define	GTF_CELL_GRAN			8
375 	/* 3) Minimum vertical porch (lines) - default 3 */
376 #define	GTF_MIN_V_PORCH			1
377 	/* width of vsync in lines */
378 #define V_SYNC_RQD			3
379 	/* width of hsync as % of total line */
380 #define H_SYNC_PERCENT			8
381 	/* min time of vsync + back porch (microsec) */
382 #define MIN_VSYNC_PLUS_BP		550
383 	/* C' and M' are part of the Blanking Duty Cycle computation */
384 #define GTF_C_PRIME	((((GTF_2C - GTF_2J) * GTF_K / 256) + GTF_2J) / 2)
385 #define GTF_M_PRIME	(GTF_K * GTF_M / 256)
386 	struct drm_display_mode *drm_mode;
387 	unsigned int hdisplay_rnd, vdisplay_rnd, vfieldrate_rqd;
388 	int top_margin, bottom_margin;
389 	int interlace;
390 	unsigned int hfreq_est;
391 	int vsync_plus_bp, vback_porch;
392 	unsigned int vtotal_lines, vfieldrate_est, hperiod;
393 	unsigned int vfield_rate, vframe_rate;
394 	int left_margin, right_margin;
395 	unsigned int total_active_pixels, ideal_duty_cycle;
396 	unsigned int hblank, total_pixels, pixel_freq;
397 	int hsync, hfront_porch, vodd_front_porch_lines;
398 	unsigned int tmp1, tmp2;
399 
400 	drm_mode = drm_mode_create(dev);
401 	if (!drm_mode)
402 		return NULL;
403 
404 	/* 1. In order to give correct results, the number of horizontal
405 	 * pixels requested is first processed to ensure that it is divisible
406 	 * by the character size, by rounding it to the nearest character
407 	 * cell boundary:
408 	 */
409 	hdisplay_rnd = (hdisplay + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN;
410 	hdisplay_rnd = hdisplay_rnd * GTF_CELL_GRAN;
411 
412 	/* 2. If interlace is requested, the number of vertical lines assumed
413 	 * by the calculation must be halved, as the computation calculates
414 	 * the number of vertical lines per field.
415 	 */
416 	if (interlaced)
417 		vdisplay_rnd = vdisplay / 2;
418 	else
419 		vdisplay_rnd = vdisplay;
420 
421 	/* 3. Find the frame rate required: */
422 	if (interlaced)
423 		vfieldrate_rqd = vrefresh * 2;
424 	else
425 		vfieldrate_rqd = vrefresh;
426 
427 	/* 4. Find number of lines in Top margin: */
428 	top_margin = 0;
429 	if (margins)
430 		top_margin = (vdisplay_rnd * GTF_MARGIN_PERCENTAGE + 500) /
431 				1000;
432 	/* 5. Find number of lines in bottom margin: */
433 	bottom_margin = top_margin;
434 
435 	/* 6. If interlace is required, then set variable interlace: */
436 	if (interlaced)
437 		interlace = 1;
438 	else
439 		interlace = 0;
440 
441 	/* 7. Estimate the Horizontal frequency */
442 	{
443 		tmp1 = (1000000  - MIN_VSYNC_PLUS_BP * vfieldrate_rqd) / 500;
444 		tmp2 = (vdisplay_rnd + 2 * top_margin + GTF_MIN_V_PORCH) *
445 				2 + interlace;
446 		hfreq_est = (tmp2 * 1000 * vfieldrate_rqd) / tmp1;
447 	}
448 
449 	/* 8. Find the number of lines in V sync + back porch */
450 	/* [V SYNC+BP] = RINT(([MIN VSYNC+BP] * hfreq_est / 1000000)) */
451 	vsync_plus_bp = MIN_VSYNC_PLUS_BP * hfreq_est / 1000;
452 	vsync_plus_bp = (vsync_plus_bp + 500) / 1000;
453 	/*  9. Find the number of lines in V back porch alone: */
454 	vback_porch = vsync_plus_bp - V_SYNC_RQD;
455 	/*  10. Find the total number of lines in Vertical field period: */
456 	vtotal_lines = vdisplay_rnd + top_margin + bottom_margin +
457 			vsync_plus_bp + GTF_MIN_V_PORCH;
458 	/*  11. Estimate the Vertical field frequency: */
459 	vfieldrate_est = hfreq_est / vtotal_lines;
460 	/*  12. Find the actual horizontal period: */
461 	hperiod = 1000000 / (vfieldrate_rqd * vtotal_lines);
462 
463 	/*  13. Find the actual Vertical field frequency: */
464 	vfield_rate = hfreq_est / vtotal_lines;
465 	/*  14. Find the Vertical frame frequency: */
466 	if (interlaced)
467 		vframe_rate = vfield_rate / 2;
468 	else
469 		vframe_rate = vfield_rate;
470 	/*  15. Find number of pixels in left margin: */
471 	if (margins)
472 		left_margin = (hdisplay_rnd * GTF_MARGIN_PERCENTAGE + 500) /
473 				1000;
474 	else
475 		left_margin = 0;
476 
477 	/* 16.Find number of pixels in right margin: */
478 	right_margin = left_margin;
479 	/* 17.Find total number of active pixels in image and left and right */
480 	total_active_pixels = hdisplay_rnd + left_margin + right_margin;
481 	/* 18.Find the ideal blanking duty cycle from blanking duty cycle */
482 	ideal_duty_cycle = GTF_C_PRIME * 1000 -
483 				(GTF_M_PRIME * 1000000 / hfreq_est);
484 	/* 19.Find the number of pixels in the blanking time to the nearest
485 	 * double character cell: */
486 	hblank = total_active_pixels * ideal_duty_cycle /
487 			(100000 - ideal_duty_cycle);
488 	hblank = (hblank + GTF_CELL_GRAN) / (2 * GTF_CELL_GRAN);
489 	hblank = hblank * 2 * GTF_CELL_GRAN;
490 	/* 20.Find total number of pixels: */
491 	total_pixels = total_active_pixels + hblank;
492 	/* 21.Find pixel clock frequency: */
493 	pixel_freq = total_pixels * hfreq_est / 1000;
494 	/* Stage 1 computations are now complete; I should really pass
495 	 * the results to another function and do the Stage 2 computations,
496 	 * but I only need a few more values so I'll just append the
497 	 * computations here for now */
498 	/* 17. Find the number of pixels in the horizontal sync period: */
499 	hsync = H_SYNC_PERCENT * total_pixels / 100;
500 	hsync = (hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN;
501 	hsync = hsync * GTF_CELL_GRAN;
502 	/* 18. Find the number of pixels in horizontal front porch period */
503 	hfront_porch = hblank / 2 - hsync;
504 	/*  36. Find the number of lines in the odd front porch period: */
505 	vodd_front_porch_lines = GTF_MIN_V_PORCH ;
506 
507 	/* finally, pack the results in the mode struct */
508 	drm_mode->hdisplay = hdisplay_rnd;
509 	drm_mode->hsync_start = hdisplay_rnd + hfront_porch;
510 	drm_mode->hsync_end = drm_mode->hsync_start + hsync;
511 	drm_mode->htotal = total_pixels;
512 	drm_mode->vdisplay = vdisplay_rnd;
513 	drm_mode->vsync_start = vdisplay_rnd + vodd_front_porch_lines;
514 	drm_mode->vsync_end = drm_mode->vsync_start + V_SYNC_RQD;
515 	drm_mode->vtotal = vtotal_lines;
516 
517 	drm_mode->clock = pixel_freq;
518 
519 	if (interlaced) {
520 		drm_mode->vtotal *= 2;
521 		drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
522 	}
523 
524 	drm_mode_set_name(drm_mode);
525 	if (GTF_M == 600 && GTF_2C == 80 && GTF_K == 128 && GTF_2J == 40)
526 		drm_mode->flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC;
527 	else
528 		drm_mode->flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NVSYNC;
529 
530 	return drm_mode;
531 }
532 EXPORT_SYMBOL(drm_gtf_mode_complex);
533 
534 /**
535  * drm_gtf_mode - create the modeline based on the GTF algorithm
536  * @dev: drm device
537  * @hdisplay: hdisplay size
538  * @vdisplay: vdisplay size
539  * @vrefresh: vrefresh rate.
540  * @interlaced: whether to compute an interlaced mode
541  * @margins: desired margin (borders) size
542  *
543  * return the modeline based on GTF algorithm
544  *
545  * This function is to create the modeline based on the GTF algorithm.
546  * Generalized Timing Formula is derived from:
547  *	GTF Spreadsheet by Andy Morrish (1/5/97)
548  *	available at http://www.vesa.org
549  *
550  * And it is copied from the file of xserver/hw/xfree86/modes/xf86gtf.c.
551  * What I have done is to translate it by using integer calculation.
552  * I also refer to the function of fb_get_mode in the file of
553  * drivers/video/fbmon.c
554  *
555  * Standard GTF parameters:
556  * M = 600
557  * C = 40
558  * K = 128
559  * J = 20
560  *
561  * Returns:
562  * The modeline based on the GTF algorithm stored in a drm_display_mode object.
563  * The display mode object is allocated with drm_mode_create(). Returns NULL
564  * when no mode could be allocated.
565  */
566 struct drm_display_mode *
567 drm_gtf_mode(struct drm_device *dev, int hdisplay, int vdisplay, int vrefresh,
568 	     bool interlaced, int margins)
569 {
570 	return drm_gtf_mode_complex(dev, hdisplay, vdisplay, vrefresh,
571 				    interlaced, margins,
572 				    600, 40 * 2, 128, 20 * 2);
573 }
574 EXPORT_SYMBOL(drm_gtf_mode);
575 
576 #ifdef CONFIG_VIDEOMODE_HELPERS
577 /**
578  * drm_display_mode_from_videomode - fill in @dmode using @vm,
579  * @vm: videomode structure to use as source
580  * @dmode: drm_display_mode structure to use as destination
581  *
582  * Fills out @dmode using the display mode specified in @vm.
583  */
584 void drm_display_mode_from_videomode(const struct videomode *vm,
585 				     struct drm_display_mode *dmode)
586 {
587 	dmode->hdisplay = vm->hactive;
588 	dmode->hsync_start = dmode->hdisplay + vm->hfront_porch;
589 	dmode->hsync_end = dmode->hsync_start + vm->hsync_len;
590 	dmode->htotal = dmode->hsync_end + vm->hback_porch;
591 
592 	dmode->vdisplay = vm->vactive;
593 	dmode->vsync_start = dmode->vdisplay + vm->vfront_porch;
594 	dmode->vsync_end = dmode->vsync_start + vm->vsync_len;
595 	dmode->vtotal = dmode->vsync_end + vm->vback_porch;
596 
597 	dmode->clock = vm->pixelclock / 1000;
598 
599 	dmode->flags = 0;
600 	if (vm->flags & DISPLAY_FLAGS_HSYNC_HIGH)
601 		dmode->flags |= DRM_MODE_FLAG_PHSYNC;
602 	else if (vm->flags & DISPLAY_FLAGS_HSYNC_LOW)
603 		dmode->flags |= DRM_MODE_FLAG_NHSYNC;
604 	if (vm->flags & DISPLAY_FLAGS_VSYNC_HIGH)
605 		dmode->flags |= DRM_MODE_FLAG_PVSYNC;
606 	else if (vm->flags & DISPLAY_FLAGS_VSYNC_LOW)
607 		dmode->flags |= DRM_MODE_FLAG_NVSYNC;
608 	if (vm->flags & DISPLAY_FLAGS_INTERLACED)
609 		dmode->flags |= DRM_MODE_FLAG_INTERLACE;
610 	if (vm->flags & DISPLAY_FLAGS_DOUBLESCAN)
611 		dmode->flags |= DRM_MODE_FLAG_DBLSCAN;
612 	if (vm->flags & DISPLAY_FLAGS_DOUBLECLK)
613 		dmode->flags |= DRM_MODE_FLAG_DBLCLK;
614 	drm_mode_set_name(dmode);
615 }
616 EXPORT_SYMBOL_GPL(drm_display_mode_from_videomode);
617 
618 /**
619  * drm_display_mode_to_videomode - fill in @vm using @dmode,
620  * @dmode: drm_display_mode structure to use as source
621  * @vm: videomode structure to use as destination
622  *
623  * Fills out @vm using the display mode specified in @dmode.
624  */
625 void drm_display_mode_to_videomode(const struct drm_display_mode *dmode,
626 				   struct videomode *vm)
627 {
628 	vm->hactive = dmode->hdisplay;
629 	vm->hfront_porch = dmode->hsync_start - dmode->hdisplay;
630 	vm->hsync_len = dmode->hsync_end - dmode->hsync_start;
631 	vm->hback_porch = dmode->htotal - dmode->hsync_end;
632 
633 	vm->vactive = dmode->vdisplay;
634 	vm->vfront_porch = dmode->vsync_start - dmode->vdisplay;
635 	vm->vsync_len = dmode->vsync_end - dmode->vsync_start;
636 	vm->vback_porch = dmode->vtotal - dmode->vsync_end;
637 
638 	vm->pixelclock = dmode->clock * 1000;
639 
640 	vm->flags = 0;
641 	if (dmode->flags & DRM_MODE_FLAG_PHSYNC)
642 		vm->flags |= DISPLAY_FLAGS_HSYNC_HIGH;
643 	else if (dmode->flags & DRM_MODE_FLAG_NHSYNC)
644 		vm->flags |= DISPLAY_FLAGS_HSYNC_LOW;
645 	if (dmode->flags & DRM_MODE_FLAG_PVSYNC)
646 		vm->flags |= DISPLAY_FLAGS_VSYNC_HIGH;
647 	else if (dmode->flags & DRM_MODE_FLAG_NVSYNC)
648 		vm->flags |= DISPLAY_FLAGS_VSYNC_LOW;
649 	if (dmode->flags & DRM_MODE_FLAG_INTERLACE)
650 		vm->flags |= DISPLAY_FLAGS_INTERLACED;
651 	if (dmode->flags & DRM_MODE_FLAG_DBLSCAN)
652 		vm->flags |= DISPLAY_FLAGS_DOUBLESCAN;
653 	if (dmode->flags & DRM_MODE_FLAG_DBLCLK)
654 		vm->flags |= DISPLAY_FLAGS_DOUBLECLK;
655 }
656 EXPORT_SYMBOL_GPL(drm_display_mode_to_videomode);
657 
658 #ifdef CONFIG_OF
659 /**
660  * of_get_drm_display_mode - get a drm_display_mode from devicetree
661  * @np: device_node with the timing specification
662  * @dmode: will be set to the return value
663  * @index: index into the list of display timings in devicetree
664  *
665  * This function is expensive and should only be used, if only one mode is to be
666  * read from DT. To get multiple modes start with of_get_display_timings and
667  * work with that instead.
668  *
669  * Returns:
670  * 0 on success, a negative errno code when no of videomode node was found.
671  */
672 int of_get_drm_display_mode(struct device_node *np,
673 			    struct drm_display_mode *dmode, int index)
674 {
675 	struct videomode vm;
676 	int ret;
677 
678 	ret = of_get_videomode(np, &vm, index);
679 	if (ret)
680 		return ret;
681 
682 	drm_display_mode_from_videomode(&vm, dmode);
683 
684 	pr_debug("%s: got %dx%d display mode from %s\n",
685 		of_node_full_name(np), vm.hactive, vm.vactive, np->name);
686 	drm_mode_debug_printmodeline(dmode);
687 
688 	return 0;
689 }
690 EXPORT_SYMBOL_GPL(of_get_drm_display_mode);
691 #endif /* CONFIG_OF */
692 #endif /* CONFIG_VIDEOMODE_HELPERS */
693 
694 /**
695  * drm_mode_set_name - set the name on a mode
696  * @mode: name will be set in this mode
697  *
698  * Set the name of @mode to a standard format which is <hdisplay>x<vdisplay>
699  * with an optional 'i' suffix for interlaced modes.
700  */
701 void drm_mode_set_name(struct drm_display_mode *mode)
702 {
703 	bool interlaced = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
704 
705 	snprintf(mode->name, DRM_DISPLAY_MODE_LEN, "%dx%d%s",
706 		 mode->hdisplay, mode->vdisplay,
707 		 interlaced ? "i" : "");
708 }
709 EXPORT_SYMBOL(drm_mode_set_name);
710 
711 /** drm_mode_hsync - get the hsync of a mode
712  * @mode: mode
713  *
714  * Returns:
715  * @modes's hsync rate in kHz, rounded to the nearest integer. Calculates the
716  * value first if it is not yet set.
717  */
718 int drm_mode_hsync(const struct drm_display_mode *mode)
719 {
720 	unsigned int calc_val;
721 
722 	if (mode->hsync)
723 		return mode->hsync;
724 
725 	if (mode->htotal < 0)
726 		return 0;
727 
728 	calc_val = (mode->clock * 1000) / mode->htotal; /* hsync in Hz */
729 	calc_val += 500;				/* round to 1000Hz */
730 	calc_val /= 1000;				/* truncate to kHz */
731 
732 	return calc_val;
733 }
734 EXPORT_SYMBOL(drm_mode_hsync);
735 
736 /**
737  * drm_mode_vrefresh - get the vrefresh of a mode
738  * @mode: mode
739  *
740  * Returns:
741  * @modes's vrefresh rate in Hz, rounded to the nearest integer. Calculates the
742  * value first if it is not yet set.
743  */
744 int drm_mode_vrefresh(const struct drm_display_mode *mode)
745 {
746 	int refresh = 0;
747 	unsigned int calc_val;
748 
749 	if (mode->vrefresh > 0)
750 		refresh = mode->vrefresh;
751 	else if (mode->htotal > 0 && mode->vtotal > 0) {
752 		int vtotal;
753 		vtotal = mode->vtotal;
754 		/* work out vrefresh the value will be x1000 */
755 		calc_val = (mode->clock * 1000);
756 		calc_val /= mode->htotal;
757 		refresh = (calc_val + vtotal / 2) / vtotal;
758 
759 		if (mode->flags & DRM_MODE_FLAG_INTERLACE)
760 			refresh *= 2;
761 		if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
762 			refresh /= 2;
763 		if (mode->vscan > 1)
764 			refresh /= mode->vscan;
765 	}
766 	return refresh;
767 }
768 EXPORT_SYMBOL(drm_mode_vrefresh);
769 
770 /**
771  * drm_mode_set_crtcinfo - set CRTC modesetting timing parameters
772  * @p: mode
773  * @adjust_flags: a combination of adjustment flags
774  *
775  * Setup the CRTC modesetting timing parameters for @p, adjusting if necessary.
776  *
777  * - The CRTC_INTERLACE_HALVE_V flag can be used to halve vertical timings of
778  *   interlaced modes.
779  * - The CRTC_STEREO_DOUBLE flag can be used to compute the timings for
780  *   buffers containing two eyes (only adjust the timings when needed, eg. for
781  *   "frame packing" or "side by side full").
782  * - The CRTC_NO_DBLSCAN and CRTC_NO_VSCAN flags request that adjustment *not*
783  *   be performed for doublescan and vscan > 1 modes respectively.
784  */
785 void drm_mode_set_crtcinfo(struct drm_display_mode *p, int adjust_flags)
786 {
787 	if ((p == NULL) || ((p->type & DRM_MODE_TYPE_CRTC_C) == DRM_MODE_TYPE_BUILTIN))
788 		return;
789 
790 	p->crtc_clock = p->clock;
791 	p->crtc_hdisplay = p->hdisplay;
792 	p->crtc_hsync_start = p->hsync_start;
793 	p->crtc_hsync_end = p->hsync_end;
794 	p->crtc_htotal = p->htotal;
795 	p->crtc_hskew = p->hskew;
796 	p->crtc_vdisplay = p->vdisplay;
797 	p->crtc_vsync_start = p->vsync_start;
798 	p->crtc_vsync_end = p->vsync_end;
799 	p->crtc_vtotal = p->vtotal;
800 
801 	if (p->flags & DRM_MODE_FLAG_INTERLACE) {
802 		if (adjust_flags & CRTC_INTERLACE_HALVE_V) {
803 			p->crtc_vdisplay /= 2;
804 			p->crtc_vsync_start /= 2;
805 			p->crtc_vsync_end /= 2;
806 			p->crtc_vtotal /= 2;
807 		}
808 	}
809 
810 	if (!(adjust_flags & CRTC_NO_DBLSCAN)) {
811 		if (p->flags & DRM_MODE_FLAG_DBLSCAN) {
812 			p->crtc_vdisplay *= 2;
813 			p->crtc_vsync_start *= 2;
814 			p->crtc_vsync_end *= 2;
815 			p->crtc_vtotal *= 2;
816 		}
817 	}
818 
819 	if (!(adjust_flags & CRTC_NO_VSCAN)) {
820 		if (p->vscan > 1) {
821 			p->crtc_vdisplay *= p->vscan;
822 			p->crtc_vsync_start *= p->vscan;
823 			p->crtc_vsync_end *= p->vscan;
824 			p->crtc_vtotal *= p->vscan;
825 		}
826 	}
827 
828 	if (adjust_flags & CRTC_STEREO_DOUBLE) {
829 		unsigned int layout = p->flags & DRM_MODE_FLAG_3D_MASK;
830 
831 		switch (layout) {
832 		case DRM_MODE_FLAG_3D_FRAME_PACKING:
833 			p->crtc_clock *= 2;
834 			p->crtc_vdisplay += p->crtc_vtotal;
835 			p->crtc_vsync_start += p->crtc_vtotal;
836 			p->crtc_vsync_end += p->crtc_vtotal;
837 			p->crtc_vtotal += p->crtc_vtotal;
838 			break;
839 		}
840 	}
841 
842 	p->crtc_vblank_start = min(p->crtc_vsync_start, p->crtc_vdisplay);
843 	p->crtc_vblank_end = max(p->crtc_vsync_end, p->crtc_vtotal);
844 	p->crtc_hblank_start = min(p->crtc_hsync_start, p->crtc_hdisplay);
845 	p->crtc_hblank_end = max(p->crtc_hsync_end, p->crtc_htotal);
846 }
847 EXPORT_SYMBOL(drm_mode_set_crtcinfo);
848 
849 /**
850  * drm_mode_copy - copy the mode
851  * @dst: mode to overwrite
852  * @src: mode to copy
853  *
854  * Copy an existing mode into another mode, preserving the object id and
855  * list head of the destination mode.
856  */
857 void drm_mode_copy(struct drm_display_mode *dst, const struct drm_display_mode *src)
858 {
859 	int id = dst->base.id;
860 	struct list_head head = dst->head;
861 
862 	*dst = *src;
863 	dst->base.id = id;
864 	dst->head = head;
865 }
866 EXPORT_SYMBOL(drm_mode_copy);
867 
868 /**
869  * drm_mode_duplicate - allocate and duplicate an existing mode
870  * @dev: drm_device to allocate the duplicated mode for
871  * @mode: mode to duplicate
872  *
873  * Just allocate a new mode, copy the existing mode into it, and return
874  * a pointer to it.  Used to create new instances of established modes.
875  *
876  * Returns:
877  * Pointer to duplicated mode on success, NULL on error.
878  */
879 struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev,
880 					    const struct drm_display_mode *mode)
881 {
882 	struct drm_display_mode *nmode;
883 
884 	nmode = drm_mode_create(dev);
885 	if (!nmode)
886 		return NULL;
887 
888 	drm_mode_copy(nmode, mode);
889 
890 	return nmode;
891 }
892 EXPORT_SYMBOL(drm_mode_duplicate);
893 
894 /**
895  * drm_mode_equal - test modes for equality
896  * @mode1: first mode
897  * @mode2: second mode
898  *
899  * Check to see if @mode1 and @mode2 are equivalent.
900  *
901  * Returns:
902  * True if the modes are equal, false otherwise.
903  */
904 bool drm_mode_equal(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
905 {
906 	if (!mode1 && !mode2)
907 		return true;
908 
909 	if (!mode1 || !mode2)
910 		return false;
911 
912 	/* do clock check convert to PICOS so fb modes get matched
913 	 * the same */
914 	if (mode1->clock && mode2->clock) {
915 		if (KHZ2PICOS(mode1->clock) != KHZ2PICOS(mode2->clock))
916 			return false;
917 	} else if (mode1->clock != mode2->clock)
918 		return false;
919 
920 	if ((mode1->flags & DRM_MODE_FLAG_3D_MASK) !=
921 	    (mode2->flags & DRM_MODE_FLAG_3D_MASK))
922 		return false;
923 
924 	return drm_mode_equal_no_clocks_no_stereo(mode1, mode2);
925 }
926 EXPORT_SYMBOL(drm_mode_equal);
927 
928 /**
929  * drm_mode_equal_no_clocks_no_stereo - test modes for equality
930  * @mode1: first mode
931  * @mode2: second mode
932  *
933  * Check to see if @mode1 and @mode2 are equivalent, but
934  * don't check the pixel clocks nor the stereo layout.
935  *
936  * Returns:
937  * True if the modes are equal, false otherwise.
938  */
939 bool drm_mode_equal_no_clocks_no_stereo(const struct drm_display_mode *mode1,
940 					const struct drm_display_mode *mode2)
941 {
942 	if (mode1->hdisplay == mode2->hdisplay &&
943 	    mode1->hsync_start == mode2->hsync_start &&
944 	    mode1->hsync_end == mode2->hsync_end &&
945 	    mode1->htotal == mode2->htotal &&
946 	    mode1->hskew == mode2->hskew &&
947 	    mode1->vdisplay == mode2->vdisplay &&
948 	    mode1->vsync_start == mode2->vsync_start &&
949 	    mode1->vsync_end == mode2->vsync_end &&
950 	    mode1->vtotal == mode2->vtotal &&
951 	    mode1->vscan == mode2->vscan &&
952 	    (mode1->flags & ~DRM_MODE_FLAG_3D_MASK) ==
953 	     (mode2->flags & ~DRM_MODE_FLAG_3D_MASK))
954 		return true;
955 
956 	return false;
957 }
958 EXPORT_SYMBOL(drm_mode_equal_no_clocks_no_stereo);
959 
960 /**
961  * drm_mode_validate_basic - make sure the mode is somewhat sane
962  * @mode: mode to check
963  *
964  * Check that the mode timings are at least somewhat reasonable.
965  * Any hardware specific limits are left up for each driver to check.
966  *
967  * Returns:
968  * The mode status
969  */
970 enum drm_mode_status
971 drm_mode_validate_basic(const struct drm_display_mode *mode)
972 {
973 	if (mode->clock == 0)
974 		return MODE_CLOCK_LOW;
975 
976 	if (mode->hdisplay == 0 ||
977 	    mode->hsync_start < mode->hdisplay ||
978 	    mode->hsync_end < mode->hsync_start ||
979 	    mode->htotal < mode->hsync_end)
980 		return MODE_H_ILLEGAL;
981 
982 	if (mode->vdisplay == 0 ||
983 	    mode->vsync_start < mode->vdisplay ||
984 	    mode->vsync_end < mode->vsync_start ||
985 	    mode->vtotal < mode->vsync_end)
986 		return MODE_V_ILLEGAL;
987 
988 	return MODE_OK;
989 }
990 EXPORT_SYMBOL(drm_mode_validate_basic);
991 
992 /**
993  * drm_mode_validate_size - make sure modes adhere to size constraints
994  * @mode: mode to check
995  * @maxX: maximum width
996  * @maxY: maximum height
997  *
998  * This function is a helper which can be used to validate modes against size
999  * limitations of the DRM device/connector. If a mode is too big its status
1000  * member is updated with the appropriate validation failure code. The list
1001  * itself is not changed.
1002  *
1003  * Returns:
1004  * The mode status
1005  */
1006 enum drm_mode_status
1007 drm_mode_validate_size(const struct drm_display_mode *mode,
1008 		       int maxX, int maxY)
1009 {
1010 	if (maxX > 0 && mode->hdisplay > maxX)
1011 		return MODE_VIRTUAL_X;
1012 
1013 	if (maxY > 0 && mode->vdisplay > maxY)
1014 		return MODE_VIRTUAL_Y;
1015 
1016 	return MODE_OK;
1017 }
1018 EXPORT_SYMBOL(drm_mode_validate_size);
1019 
1020 #define MODE_STATUS(status) [MODE_ ## status + 3] = #status
1021 
1022 static const char * const drm_mode_status_names[] = {
1023 	MODE_STATUS(OK),
1024 	MODE_STATUS(HSYNC),
1025 	MODE_STATUS(VSYNC),
1026 	MODE_STATUS(H_ILLEGAL),
1027 	MODE_STATUS(V_ILLEGAL),
1028 	MODE_STATUS(BAD_WIDTH),
1029 	MODE_STATUS(NOMODE),
1030 	MODE_STATUS(NO_INTERLACE),
1031 	MODE_STATUS(NO_DBLESCAN),
1032 	MODE_STATUS(NO_VSCAN),
1033 	MODE_STATUS(MEM),
1034 	MODE_STATUS(VIRTUAL_X),
1035 	MODE_STATUS(VIRTUAL_Y),
1036 	MODE_STATUS(MEM_VIRT),
1037 	MODE_STATUS(NOCLOCK),
1038 	MODE_STATUS(CLOCK_HIGH),
1039 	MODE_STATUS(CLOCK_LOW),
1040 	MODE_STATUS(CLOCK_RANGE),
1041 	MODE_STATUS(BAD_HVALUE),
1042 	MODE_STATUS(BAD_VVALUE),
1043 	MODE_STATUS(BAD_VSCAN),
1044 	MODE_STATUS(HSYNC_NARROW),
1045 	MODE_STATUS(HSYNC_WIDE),
1046 	MODE_STATUS(HBLANK_NARROW),
1047 	MODE_STATUS(HBLANK_WIDE),
1048 	MODE_STATUS(VSYNC_NARROW),
1049 	MODE_STATUS(VSYNC_WIDE),
1050 	MODE_STATUS(VBLANK_NARROW),
1051 	MODE_STATUS(VBLANK_WIDE),
1052 	MODE_STATUS(PANEL),
1053 	MODE_STATUS(INTERLACE_WIDTH),
1054 	MODE_STATUS(ONE_WIDTH),
1055 	MODE_STATUS(ONE_HEIGHT),
1056 	MODE_STATUS(ONE_SIZE),
1057 	MODE_STATUS(NO_REDUCED),
1058 	MODE_STATUS(NO_STEREO),
1059 	MODE_STATUS(UNVERIFIED),
1060 	MODE_STATUS(BAD),
1061 	MODE_STATUS(ERROR),
1062 };
1063 
1064 #undef MODE_STATUS
1065 
1066 static const char *drm_get_mode_status_name(enum drm_mode_status status)
1067 {
1068 	int index = status + 3;
1069 
1070 	if (WARN_ON(index < 0 || index >= ARRAY_SIZE(drm_mode_status_names)))
1071 		return "";
1072 
1073 	return drm_mode_status_names[index];
1074 }
1075 
1076 /**
1077  * drm_mode_prune_invalid - remove invalid modes from mode list
1078  * @dev: DRM device
1079  * @mode_list: list of modes to check
1080  * @verbose: be verbose about it
1081  *
1082  * This helper function can be used to prune a display mode list after
1083  * validation has been completed. All modes who's status is not MODE_OK will be
1084  * removed from the list, and if @verbose the status code and mode name is also
1085  * printed to dmesg.
1086  */
1087 void drm_mode_prune_invalid(struct drm_device *dev,
1088 			    struct list_head *mode_list, bool verbose)
1089 {
1090 	struct drm_display_mode *mode, *t;
1091 
1092 	list_for_each_entry_safe(mode, t, mode_list, head) {
1093 		if (mode->status != MODE_OK) {
1094 			list_del(&mode->head);
1095 			if (verbose) {
1096 				drm_mode_debug_printmodeline(mode);
1097 				DRM_DEBUG_KMS("Not using %s mode: %s\n",
1098 					      mode->name,
1099 					      drm_get_mode_status_name(mode->status));
1100 			}
1101 			drm_mode_destroy(dev, mode);
1102 		}
1103 	}
1104 }
1105 EXPORT_SYMBOL(drm_mode_prune_invalid);
1106 
1107 /**
1108  * drm_mode_compare - compare modes for favorability
1109  * @priv: unused
1110  * @lh_a: list_head for first mode
1111  * @lh_b: list_head for second mode
1112  *
1113  * Compare two modes, given by @lh_a and @lh_b, returning a value indicating
1114  * which is better.
1115  *
1116  * Returns:
1117  * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or
1118  * positive if @lh_b is better than @lh_a.
1119  */
1120 static int drm_mode_compare(void *priv, struct list_head *lh_a, struct list_head *lh_b)
1121 {
1122 	struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head);
1123 	struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head);
1124 	int diff;
1125 
1126 	diff = ((b->type & DRM_MODE_TYPE_PREFERRED) != 0) -
1127 		((a->type & DRM_MODE_TYPE_PREFERRED) != 0);
1128 	if (diff)
1129 		return diff;
1130 	diff = b->hdisplay * b->vdisplay - a->hdisplay * a->vdisplay;
1131 	if (diff)
1132 		return diff;
1133 
1134 	diff = b->vrefresh - a->vrefresh;
1135 	if (diff)
1136 		return diff;
1137 
1138 	diff = b->clock - a->clock;
1139 	return diff;
1140 }
1141 
1142 /**
1143  * drm_mode_sort - sort mode list
1144  * @mode_list: list of drm_display_mode structures to sort
1145  *
1146  * Sort @mode_list by favorability, moving good modes to the head of the list.
1147  */
1148 void drm_mode_sort(struct list_head *mode_list)
1149 {
1150 	list_sort(NULL, mode_list, drm_mode_compare);
1151 }
1152 EXPORT_SYMBOL(drm_mode_sort);
1153 
1154 /**
1155  * drm_mode_connector_list_update - update the mode list for the connector
1156  * @connector: the connector to update
1157  * @merge_type_bits: whether to merge or overwrite type bits
1158  *
1159  * This moves the modes from the @connector probed_modes list
1160  * to the actual mode list. It compares the probed mode against the current
1161  * list and only adds different/new modes.
1162  *
1163  * This is just a helper functions doesn't validate any modes itself and also
1164  * doesn't prune any invalid modes. Callers need to do that themselves.
1165  */
1166 void drm_mode_connector_list_update(struct drm_connector *connector,
1167 				    bool merge_type_bits)
1168 {
1169 	struct drm_display_mode *mode;
1170 	struct drm_display_mode *pmode, *pt;
1171 	int found_it;
1172 
1173 	WARN_ON(!mutex_is_locked(&connector->dev->mode_config.mutex));
1174 
1175 	list_for_each_entry_safe(pmode, pt, &connector->probed_modes,
1176 				 head) {
1177 		found_it = 0;
1178 		/* go through current modes checking for the new probed mode */
1179 		list_for_each_entry(mode, &connector->modes, head) {
1180 			if (drm_mode_equal(pmode, mode)) {
1181 				found_it = 1;
1182 				/* if equal delete the probed mode */
1183 				mode->status = pmode->status;
1184 				/* Merge type bits together */
1185 				if (merge_type_bits)
1186 					mode->type |= pmode->type;
1187 				else
1188 					mode->type = pmode->type;
1189 				list_del(&pmode->head);
1190 				drm_mode_destroy(connector->dev, pmode);
1191 				break;
1192 			}
1193 		}
1194 
1195 		if (!found_it) {
1196 			list_move_tail(&pmode->head, &connector->modes);
1197 		}
1198 	}
1199 }
1200 EXPORT_SYMBOL(drm_mode_connector_list_update);
1201 
1202 /**
1203  * drm_mode_parse_command_line_for_connector - parse command line modeline for connector
1204  * @mode_option: optional per connector mode option
1205  * @connector: connector to parse modeline for
1206  * @mode: preallocated drm_cmdline_mode structure to fill out
1207  *
1208  * This parses @mode_option command line modeline for modes and options to
1209  * configure the connector. If @mode_option is NULL the default command line
1210  * modeline in fb_mode_option will be parsed instead.
1211  *
1212  * This uses the same parameters as the fb modedb.c, except for an extra
1213  * force-enable, force-enable-digital and force-disable bit at the end:
1214  *
1215  *	<xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
1216  *
1217  * The intermediate drm_cmdline_mode structure is required to store additional
1218  * options from the command line modline like the force-enable/disable flag.
1219  *
1220  * Returns:
1221  * True if a valid modeline has been parsed, false otherwise.
1222  */
1223 bool drm_mode_parse_command_line_for_connector(const char *mode_option,
1224 					       struct drm_connector *connector,
1225 					       struct drm_cmdline_mode *mode)
1226 {
1227 	const char *name;
1228 	unsigned int namelen;
1229 	bool res_specified = false, bpp_specified = false, refresh_specified = false;
1230 	unsigned int xres = 0, yres = 0, bpp = 32, refresh = 0;
1231 	bool yres_specified = false, cvt = false, rb = false;
1232 	bool interlace = false, margins = false, was_digit = false;
1233 	int i;
1234 	enum drm_connector_force force = DRM_FORCE_UNSPECIFIED;
1235 
1236 #ifdef CONFIG_FB
1237 	if (!mode_option)
1238 		mode_option = fb_mode_option;
1239 #endif
1240 
1241 	if (!mode_option) {
1242 		mode->specified = false;
1243 		return false;
1244 	}
1245 
1246 	name = mode_option;
1247 	namelen = strlen(name);
1248 	for (i = namelen-1; i >= 0; i--) {
1249 		switch (name[i]) {
1250 		case '@':
1251 			if (!refresh_specified && !bpp_specified &&
1252 			    !yres_specified && !cvt && !rb && was_digit) {
1253 				refresh = simple_strtol(&name[i+1], NULL, 10);
1254 				refresh_specified = true;
1255 				was_digit = false;
1256 			} else
1257 				goto done;
1258 			break;
1259 		case '-':
1260 			if (!bpp_specified && !yres_specified && !cvt &&
1261 			    !rb && was_digit) {
1262 				bpp = simple_strtol(&name[i+1], NULL, 10);
1263 				bpp_specified = true;
1264 				was_digit = false;
1265 			} else
1266 				goto done;
1267 			break;
1268 		case 'x':
1269 			if (!yres_specified && was_digit) {
1270 				yres = simple_strtol(&name[i+1], NULL, 10);
1271 				yres_specified = true;
1272 				was_digit = false;
1273 			} else
1274 				goto done;
1275 			break;
1276 		case '0' ... '9':
1277 			was_digit = true;
1278 			break;
1279 		case 'M':
1280 			if (yres_specified || cvt || was_digit)
1281 				goto done;
1282 			cvt = true;
1283 			break;
1284 		case 'R':
1285 			if (yres_specified || cvt || rb || was_digit)
1286 				goto done;
1287 			rb = true;
1288 			break;
1289 		case 'm':
1290 			if (cvt || yres_specified || was_digit)
1291 				goto done;
1292 			margins = true;
1293 			break;
1294 		case 'i':
1295 			if (cvt || yres_specified || was_digit)
1296 				goto done;
1297 			interlace = true;
1298 			break;
1299 		case 'e':
1300 			if (yres_specified || bpp_specified || refresh_specified ||
1301 			    was_digit || (force != DRM_FORCE_UNSPECIFIED))
1302 				goto done;
1303 
1304 			force = DRM_FORCE_ON;
1305 			break;
1306 		case 'D':
1307 			if (yres_specified || bpp_specified || refresh_specified ||
1308 			    was_digit || (force != DRM_FORCE_UNSPECIFIED))
1309 				goto done;
1310 
1311 			if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
1312 			    (connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
1313 				force = DRM_FORCE_ON;
1314 			else
1315 				force = DRM_FORCE_ON_DIGITAL;
1316 			break;
1317 		case 'd':
1318 			if (yres_specified || bpp_specified || refresh_specified ||
1319 			    was_digit || (force != DRM_FORCE_UNSPECIFIED))
1320 				goto done;
1321 
1322 			force = DRM_FORCE_OFF;
1323 			break;
1324 		default:
1325 			goto done;
1326 		}
1327 	}
1328 
1329 	if (i < 0 && yres_specified) {
1330 		char *ch;
1331 		xres = simple_strtol(name, &ch, 10);
1332 		if ((ch != NULL) && (*ch == 'x'))
1333 			res_specified = true;
1334 		else
1335 			i = ch - name;
1336 	} else if (!yres_specified && was_digit) {
1337 		/* catch mode that begins with digits but has no 'x' */
1338 		i = 0;
1339 	}
1340 done:
1341 	if (i >= 0) {
1342 		printk(KERN_WARNING
1343 			"parse error at position %i in video mode '%s'\n",
1344 			i, name);
1345 		mode->specified = false;
1346 		return false;
1347 	}
1348 
1349 	if (res_specified) {
1350 		mode->specified = true;
1351 		mode->xres = xres;
1352 		mode->yres = yres;
1353 	}
1354 
1355 	if (refresh_specified) {
1356 		mode->refresh_specified = true;
1357 		mode->refresh = refresh;
1358 	}
1359 
1360 	if (bpp_specified) {
1361 		mode->bpp_specified = true;
1362 		mode->bpp = bpp;
1363 	}
1364 	mode->rb = rb;
1365 	mode->cvt = cvt;
1366 	mode->interlace = interlace;
1367 	mode->margins = margins;
1368 	mode->force = force;
1369 
1370 	return true;
1371 }
1372 EXPORT_SYMBOL(drm_mode_parse_command_line_for_connector);
1373 
1374 /**
1375  * drm_mode_create_from_cmdline_mode - convert a command line modeline into a DRM display mode
1376  * @dev: DRM device to create the new mode for
1377  * @cmd: input command line modeline
1378  *
1379  * Returns:
1380  * Pointer to converted mode on success, NULL on error.
1381  */
1382 struct drm_display_mode *
1383 drm_mode_create_from_cmdline_mode(struct drm_device *dev,
1384 				  struct drm_cmdline_mode *cmd)
1385 {
1386 	struct drm_display_mode *mode;
1387 
1388 	if (cmd->cvt)
1389 		mode = drm_cvt_mode(dev,
1390 				    cmd->xres, cmd->yres,
1391 				    cmd->refresh_specified ? cmd->refresh : 60,
1392 				    cmd->rb, cmd->interlace,
1393 				    cmd->margins);
1394 	else
1395 		mode = drm_gtf_mode(dev,
1396 				    cmd->xres, cmd->yres,
1397 				    cmd->refresh_specified ? cmd->refresh : 60,
1398 				    cmd->interlace,
1399 				    cmd->margins);
1400 	if (!mode)
1401 		return NULL;
1402 
1403 	mode->type |= DRM_MODE_TYPE_USERDEF;
1404 	drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
1405 	return mode;
1406 }
1407 EXPORT_SYMBOL(drm_mode_create_from_cmdline_mode);
1408 
1409 /**
1410  * drm_crtc_convert_to_umode - convert a drm_display_mode into a modeinfo
1411  * @out: drm_mode_modeinfo struct to return to the user
1412  * @in: drm_display_mode to use
1413  *
1414  * Convert a drm_display_mode into a drm_mode_modeinfo structure to return to
1415  * the user.
1416  */
1417 void drm_mode_convert_to_umode(struct drm_mode_modeinfo *out,
1418 			       const struct drm_display_mode *in)
1419 {
1420 	WARN(in->hdisplay > USHRT_MAX || in->hsync_start > USHRT_MAX ||
1421 	     in->hsync_end > USHRT_MAX || in->htotal > USHRT_MAX ||
1422 	     in->hskew > USHRT_MAX || in->vdisplay > USHRT_MAX ||
1423 	     in->vsync_start > USHRT_MAX || in->vsync_end > USHRT_MAX ||
1424 	     in->vtotal > USHRT_MAX || in->vscan > USHRT_MAX,
1425 	     "timing values too large for mode info\n");
1426 
1427 	out->clock = in->clock;
1428 	out->hdisplay = in->hdisplay;
1429 	out->hsync_start = in->hsync_start;
1430 	out->hsync_end = in->hsync_end;
1431 	out->htotal = in->htotal;
1432 	out->hskew = in->hskew;
1433 	out->vdisplay = in->vdisplay;
1434 	out->vsync_start = in->vsync_start;
1435 	out->vsync_end = in->vsync_end;
1436 	out->vtotal = in->vtotal;
1437 	out->vscan = in->vscan;
1438 	out->vrefresh = in->vrefresh;
1439 	out->flags = in->flags;
1440 	out->type = in->type;
1441 	strncpy(out->name, in->name, DRM_DISPLAY_MODE_LEN);
1442 	out->name[DRM_DISPLAY_MODE_LEN-1] = 0;
1443 }
1444 
1445 /**
1446  * drm_crtc_convert_umode - convert a modeinfo into a drm_display_mode
1447  * @out: drm_display_mode to return to the user
1448  * @in: drm_mode_modeinfo to use
1449  *
1450  * Convert a drm_mode_modeinfo into a drm_display_mode structure to return to
1451  * the caller.
1452  *
1453  * Returns:
1454  * Zero on success, negative errno on failure.
1455  */
1456 int drm_mode_convert_umode(struct drm_display_mode *out,
1457 			   const struct drm_mode_modeinfo *in)
1458 {
1459 	int ret = -EINVAL;
1460 
1461 	if (in->clock > INT_MAX || in->vrefresh > INT_MAX) {
1462 		ret = -ERANGE;
1463 		goto out;
1464 	}
1465 
1466 	if ((in->flags & DRM_MODE_FLAG_3D_MASK) > DRM_MODE_FLAG_3D_MAX)
1467 		goto out;
1468 
1469 	out->clock = in->clock;
1470 	out->hdisplay = in->hdisplay;
1471 	out->hsync_start = in->hsync_start;
1472 	out->hsync_end = in->hsync_end;
1473 	out->htotal = in->htotal;
1474 	out->hskew = in->hskew;
1475 	out->vdisplay = in->vdisplay;
1476 	out->vsync_start = in->vsync_start;
1477 	out->vsync_end = in->vsync_end;
1478 	out->vtotal = in->vtotal;
1479 	out->vscan = in->vscan;
1480 	out->vrefresh = in->vrefresh;
1481 	out->flags = in->flags;
1482 	out->type = in->type;
1483 	strncpy(out->name, in->name, DRM_DISPLAY_MODE_LEN);
1484 	out->name[DRM_DISPLAY_MODE_LEN-1] = 0;
1485 
1486 	out->status = drm_mode_validate_basic(out);
1487 	if (out->status != MODE_OK)
1488 		goto out;
1489 
1490 	ret = 0;
1491 
1492 out:
1493 	return ret;
1494 }