drm/crtc_helper: avoid NULL-pointer dereference when encoder is NULL
[safe/jmp/linux-2.6] / drivers / gpu / drm / drm_crtc_helper.c
1 /*
2  * Copyright (c) 2006-2008 Intel Corporation
3  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
4  *
5  * DRM core CRTC related functions
6  *
7  * Permission to use, copy, modify, distribute, and sell this software and its
8  * documentation for any purpose is hereby granted without fee, provided that
9  * the above copyright notice appear in all copies and that both that copyright
10  * notice and this permission notice appear in supporting documentation, and
11  * that the name of the copyright holders not be used in advertising or
12  * publicity pertaining to distribution of the software without specific,
13  * written prior permission.  The copyright holders make no representations
14  * about the suitability of this software for any purpose.  It is provided "as
15  * is" without express or implied warranty.
16  *
17  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
18  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
19  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
20  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
21  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
22  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
23  * OF THIS SOFTWARE.
24  *
25  * Authors:
26  *      Keith Packard
27  *      Eric Anholt <eric@anholt.net>
28  *      Dave Airlie <airlied@linux.ie>
29  *      Jesse Barnes <jesse.barnes@intel.com>
30  */
31
32 #include "drmP.h"
33 #include "drm_crtc.h"
34 #include "drm_crtc_helper.h"
35
36 /*
37  * Detailed mode info for 800x600@60Hz
38  */
39 static struct drm_display_mode std_modes[] = {
40         { DRM_MODE("800x600", DRM_MODE_TYPE_DEFAULT, 40000, 800, 840,
41                    968, 1056, 0, 600, 601, 605, 628, 0,
42                    DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC) },
43 };
44
45 static void drm_mode_validate_flag(struct drm_connector *connector,
46                                    int flags)
47 {
48         struct drm_display_mode *mode, *t;
49
50         if (flags == (DRM_MODE_FLAG_DBLSCAN | DRM_MODE_FLAG_INTERLACE))
51                 return;
52
53         list_for_each_entry_safe(mode, t, &connector->modes, head) {
54                 if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
55                                 !(flags & DRM_MODE_FLAG_INTERLACE))
56                         mode->status = MODE_NO_INTERLACE;
57                 if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
58                                 !(flags & DRM_MODE_FLAG_DBLSCAN))
59                         mode->status = MODE_NO_DBLESCAN;
60         }
61
62         return;
63 }
64
65 /**
66  * drm_helper_probe_connector_modes - get complete set of display modes
67  * @dev: DRM device
68  * @maxX: max width for modes
69  * @maxY: max height for modes
70  *
71  * LOCKING:
72  * Caller must hold mode config lock.
73  *
74  * Based on @dev's mode_config layout, scan all the connectors and try to detect
75  * modes on them.  Modes will first be added to the connector's probed_modes
76  * list, then culled (based on validity and the @maxX, @maxY parameters) and
77  * put into the normal modes list.
78  *
79  * Intended to be used either at bootup time or when major configuration
80  * changes have occurred.
81  *
82  * FIXME: take into account monitor limits
83  *
84  * RETURNS:
85  * Number of modes found on @connector.
86  */
87 int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
88                                             uint32_t maxX, uint32_t maxY)
89 {
90         struct drm_device *dev = connector->dev;
91         struct drm_display_mode *mode, *t;
92         struct drm_connector_helper_funcs *connector_funcs =
93                 connector->helper_private;
94         int count = 0;
95         int mode_flags = 0;
96
97         DRM_DEBUG_KMS("%s\n", drm_get_connector_name(connector));
98         /* set all modes to the unverified state */
99         list_for_each_entry_safe(mode, t, &connector->modes, head)
100                 mode->status = MODE_UNVERIFIED;
101
102         connector->status = connector->funcs->detect(connector);
103
104         if (connector->status == connector_status_disconnected) {
105                 DRM_DEBUG_KMS("%s is disconnected\n",
106                           drm_get_connector_name(connector));
107                 /* TODO set EDID to NULL */
108                 return 0;
109         }
110
111         count = (*connector_funcs->get_modes)(connector);
112         if (!count)
113                 return 0;
114
115         drm_mode_connector_list_update(connector);
116
117         if (maxX && maxY)
118                 drm_mode_validate_size(dev, &connector->modes, maxX,
119                                        maxY, 0);
120
121         if (connector->interlace_allowed)
122                 mode_flags |= DRM_MODE_FLAG_INTERLACE;
123         if (connector->doublescan_allowed)
124                 mode_flags |= DRM_MODE_FLAG_DBLSCAN;
125         drm_mode_validate_flag(connector, mode_flags);
126
127         list_for_each_entry_safe(mode, t, &connector->modes, head) {
128                 if (mode->status == MODE_OK)
129                         mode->status = connector_funcs->mode_valid(connector,
130                                                                    mode);
131         }
132
133
134         drm_mode_prune_invalid(dev, &connector->modes, true);
135
136         if (list_empty(&connector->modes))
137                 return 0;
138
139         drm_mode_sort(&connector->modes);
140
141         DRM_DEBUG_KMS("Probed modes for %s\n",
142                                 drm_get_connector_name(connector));
143         list_for_each_entry_safe(mode, t, &connector->modes, head) {
144                 mode->vrefresh = drm_mode_vrefresh(mode);
145
146                 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
147                 drm_mode_debug_printmodeline(mode);
148         }
149
150         return count;
151 }
152 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
153
154 int drm_helper_probe_connector_modes(struct drm_device *dev, uint32_t maxX,
155                                       uint32_t maxY)
156 {
157         struct drm_connector *connector;
158         int count = 0;
159
160         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
161                 count += drm_helper_probe_single_connector_modes(connector,
162                                                                  maxX, maxY);
163         }
164
165         return count;
166 }
167 EXPORT_SYMBOL(drm_helper_probe_connector_modes);
168
169 static void drm_helper_add_std_modes(struct drm_device *dev,
170                                      struct drm_connector *connector)
171 {
172         struct drm_display_mode *mode, *t;
173         int i;
174
175         for (i = 0; i < ARRAY_SIZE(std_modes); i++) {
176                 struct drm_display_mode *stdmode;
177
178                 /*
179                  * When no valid EDID modes are available we end up
180                  * here and bailed in the past, now we add some standard
181                  * modes and move on.
182                  */
183                 stdmode = drm_mode_duplicate(dev, &std_modes[i]);
184                 drm_mode_probed_add(connector, stdmode);
185                 drm_mode_list_concat(&connector->probed_modes,
186                                      &connector->modes);
187
188                 DRM_DEBUG_KMS("Adding mode %s to %s\n", stdmode->name,
189                           drm_get_connector_name(connector));
190         }
191         drm_mode_sort(&connector->modes);
192
193         DRM_DEBUG_KMS("Added std modes on %s\n",
194                         drm_get_connector_name(connector));
195         list_for_each_entry_safe(mode, t, &connector->modes, head) {
196                 mode->vrefresh = drm_mode_vrefresh(mode);
197
198                 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
199                 drm_mode_debug_printmodeline(mode);
200         }
201 }
202
203 /**
204  * drm_helper_encoder_in_use - check if a given encoder is in use
205  * @encoder: encoder to check
206  *
207  * LOCKING:
208  * Caller must hold mode config lock.
209  *
210  * Walk @encoders's DRM device's mode_config and see if it's in use.
211  *
212  * RETURNS:
213  * True if @encoder is part of the mode_config, false otherwise.
214  */
215 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
216 {
217         struct drm_connector *connector;
218         struct drm_device *dev = encoder->dev;
219         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
220                 if (connector->encoder == encoder)
221                         return true;
222         return false;
223 }
224 EXPORT_SYMBOL(drm_helper_encoder_in_use);
225
226 /**
227  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
228  * @crtc: CRTC to check
229  *
230  * LOCKING:
231  * Caller must hold mode config lock.
232  *
233  * Walk @crtc's DRM device's mode_config and see if it's in use.
234  *
235  * RETURNS:
236  * True if @crtc is part of the mode_config, false otherwise.
237  */
238 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
239 {
240         struct drm_encoder *encoder;
241         struct drm_device *dev = crtc->dev;
242         /* FIXME: Locking around list access? */
243         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head)
244                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
245                         return true;
246         return false;
247 }
248 EXPORT_SYMBOL(drm_helper_crtc_in_use);
249
250 /**
251  * drm_disable_unused_functions - disable unused objects
252  * @dev: DRM device
253  *
254  * LOCKING:
255  * Caller must hold mode config lock.
256  *
257  * If an connector or CRTC isn't part of @dev's mode_config, it can be disabled
258  * by calling its dpms function, which should power it off.
259  */
260 void drm_helper_disable_unused_functions(struct drm_device *dev)
261 {
262         struct drm_encoder *encoder;
263         struct drm_connector *connector;
264         struct drm_encoder_helper_funcs *encoder_funcs;
265         struct drm_crtc *crtc;
266
267         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
268                 if (!connector->encoder)
269                         continue;
270                 if (connector->status == connector_status_disconnected)
271                         connector->encoder = NULL;
272         }
273
274         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
275                 encoder_funcs = encoder->helper_private;
276                 if (!drm_helper_encoder_in_use(encoder)) {
277                         if (encoder_funcs->disable)
278                                 (*encoder_funcs->disable)(encoder);
279                         else
280                                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
281                         /* disconnector encoder from any connector */
282                         encoder->crtc = NULL;
283                 }
284         }
285
286         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
287                 struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
288                 crtc->enabled = drm_helper_crtc_in_use(crtc);
289                 if (!crtc->enabled) {
290                         crtc_funcs->dpms(crtc, DRM_MODE_DPMS_OFF);
291                         crtc->fb = NULL;
292                 }
293         }
294 }
295 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
296
297 static struct drm_display_mode *drm_has_preferred_mode(struct drm_connector *connector, int width, int height)
298 {
299         struct drm_display_mode *mode;
300
301         list_for_each_entry(mode, &connector->modes, head) {
302                 if (drm_mode_width(mode) > width ||
303                     drm_mode_height(mode) > height)
304                         continue;
305                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
306                         return mode;
307         }
308         return NULL;
309 }
310
311 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
312 {
313         bool enable;
314
315         if (strict) {
316                 enable = connector->status == connector_status_connected;
317         } else {
318                 enable = connector->status != connector_status_disconnected;
319         }
320         return enable;
321 }
322
323 static void drm_enable_connectors(struct drm_device *dev, bool *enabled)
324 {
325         bool any_enabled = false;
326         struct drm_connector *connector;
327         int i = 0;
328
329         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
330                 enabled[i] = drm_connector_enabled(connector, true);
331                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
332                           enabled[i] ? "yes" : "no");
333                 any_enabled |= enabled[i];
334                 i++;
335         }
336
337         if (any_enabled)
338                 return;
339
340         i = 0;
341         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
342                 enabled[i] = drm_connector_enabled(connector, false);
343                 i++;
344         }
345 }
346
347 static bool drm_target_preferred(struct drm_device *dev,
348                                  struct drm_display_mode **modes,
349                                  bool *enabled, int width, int height)
350 {
351         struct drm_connector *connector;
352         int i = 0;
353
354         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
355
356                 if (enabled[i] == false) {
357                         i++;
358                         continue;
359                 }
360
361                 DRM_DEBUG_KMS("looking for preferred mode on connector %d\n",
362                           connector->base.id);
363
364                 modes[i] = drm_has_preferred_mode(connector, width, height);
365                 /* No preferred modes, pick one off the list */
366                 if (!modes[i] && !list_empty(&connector->modes)) {
367                         list_for_each_entry(modes[i], &connector->modes, head)
368                                 break;
369                 }
370                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
371                           "none");
372                 i++;
373         }
374         return true;
375 }
376
377 static int drm_pick_crtcs(struct drm_device *dev,
378                           struct drm_crtc **best_crtcs,
379                           struct drm_display_mode **modes,
380                           int n, int width, int height)
381 {
382         int c, o;
383         struct drm_connector *connector;
384         struct drm_connector_helper_funcs *connector_funcs;
385         struct drm_encoder *encoder;
386         struct drm_crtc *best_crtc;
387         int my_score, best_score, score;
388         struct drm_crtc **crtcs, *crtc;
389
390         if (n == dev->mode_config.num_connector)
391                 return 0;
392         c = 0;
393         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
394                 if (c == n)
395                         break;
396                 c++;
397         }
398
399         best_crtcs[n] = NULL;
400         best_crtc = NULL;
401         best_score = drm_pick_crtcs(dev, best_crtcs, modes, n+1, width, height);
402         if (modes[n] == NULL)
403                 return best_score;
404
405         crtcs = kmalloc(dev->mode_config.num_connector *
406                         sizeof(struct drm_crtc *), GFP_KERNEL);
407         if (!crtcs)
408                 return best_score;
409
410         my_score = 1;
411         if (connector->status == connector_status_connected)
412                 my_score++;
413         if (drm_has_preferred_mode(connector, width, height))
414                 my_score++;
415
416         connector_funcs = connector->helper_private;
417         encoder = connector_funcs->best_encoder(connector);
418         if (!encoder)
419                 goto out;
420
421         connector->encoder = encoder;
422
423         /* select a crtc for this connector and then attempt to configure
424            remaining connectors */
425         c = 0;
426         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
427
428                 if ((encoder->possible_crtcs & (1 << c)) == 0) {
429                         c++;
430                         continue;
431                 }
432
433                 for (o = 0; o < n; o++)
434                         if (best_crtcs[o] == crtc)
435                                 break;
436
437                 if (o < n) {
438                         /* ignore cloning for now */
439                         c++;
440                         continue;
441                 }
442
443                 crtcs[n] = crtc;
444                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_crtc *));
445                 score = my_score + drm_pick_crtcs(dev, crtcs, modes, n + 1,
446                                                   width, height);
447                 if (score > best_score) {
448                         best_crtc = crtc;
449                         best_score = score;
450                         memcpy(best_crtcs, crtcs,
451                                dev->mode_config.num_connector *
452                                sizeof(struct drm_crtc *));
453                 }
454                 c++;
455         }
456 out:
457         kfree(crtcs);
458         return best_score;
459 }
460
461 static void drm_setup_crtcs(struct drm_device *dev)
462 {
463         struct drm_crtc **crtcs;
464         struct drm_display_mode **modes;
465         struct drm_encoder *encoder;
466         struct drm_connector *connector;
467         bool *enabled;
468         int width, height;
469         int i, ret;
470
471         DRM_DEBUG_KMS("\n");
472
473         width = dev->mode_config.max_width;
474         height = dev->mode_config.max_height;
475
476         /* clean out all the encoder/crtc combos */
477         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
478                 encoder->crtc = NULL;
479         }
480
481         crtcs = kcalloc(dev->mode_config.num_connector,
482                         sizeof(struct drm_crtc *), GFP_KERNEL);
483         modes = kcalloc(dev->mode_config.num_connector,
484                         sizeof(struct drm_display_mode *), GFP_KERNEL);
485         enabled = kcalloc(dev->mode_config.num_connector,
486                           sizeof(bool), GFP_KERNEL);
487
488         drm_enable_connectors(dev, enabled);
489
490         ret = drm_target_preferred(dev, modes, enabled, width, height);
491         if (!ret)
492                 DRM_ERROR("Unable to find initial modes\n");
493
494         DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n", width, height);
495
496         drm_pick_crtcs(dev, crtcs, modes, 0, width, height);
497
498         i = 0;
499         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
500                 struct drm_display_mode *mode = modes[i];
501                 struct drm_crtc *crtc = crtcs[i];
502
503                 if (connector->encoder == NULL) {
504                         i++;
505                         continue;
506                 }
507
508                 if (mode && crtc) {
509                         DRM_DEBUG_KMS("desired mode %s set on crtc %d\n",
510                                   mode->name, crtc->base.id);
511                         crtc->desired_mode = mode;
512                         connector->encoder->crtc = crtc;
513                 } else {
514                         connector->encoder->crtc = NULL;
515                         connector->encoder = NULL;
516                 }
517                 i++;
518         }
519
520         kfree(crtcs);
521         kfree(modes);
522         kfree(enabled);
523 }
524
525 /**
526  * drm_encoder_crtc_ok - can a given crtc drive a given encoder?
527  * @encoder: encoder to test
528  * @crtc: crtc to test
529  *
530  * Return false if @encoder can't be driven by @crtc, true otherwise.
531  */
532 static bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
533                                 struct drm_crtc *crtc)
534 {
535         struct drm_device *dev;
536         struct drm_crtc *tmp;
537         int crtc_mask = 1;
538
539         WARN(!crtc, "checking null crtc?");
540
541         dev = crtc->dev;
542
543         list_for_each_entry(tmp, &dev->mode_config.crtc_list, head) {
544                 if (tmp == crtc)
545                         break;
546                 crtc_mask <<= 1;
547         }
548
549         if (encoder->possible_crtcs & crtc_mask)
550                 return true;
551         return false;
552 }
553
554 /*
555  * Check the CRTC we're going to map each output to vs. its current
556  * CRTC.  If they don't match, we have to disable the output and the CRTC
557  * since the driver will have to re-route things.
558  */
559 static void
560 drm_crtc_prepare_encoders(struct drm_device *dev)
561 {
562         struct drm_encoder_helper_funcs *encoder_funcs;
563         struct drm_encoder *encoder;
564
565         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
566                 encoder_funcs = encoder->helper_private;
567                 /* Disable unused encoders */
568                 if (encoder->crtc == NULL)
569                         (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
570                 /* Disable encoders whose CRTC is about to change */
571                 if (encoder_funcs->get_crtc &&
572                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
573                         (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
574         }
575 }
576
577 /**
578  * drm_crtc_set_mode - set a mode
579  * @crtc: CRTC to program
580  * @mode: mode to use
581  * @x: width of mode
582  * @y: height of mode
583  *
584  * LOCKING:
585  * Caller must hold mode config lock.
586  *
587  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
588  * to fixup or reject the mode prior to trying to set it.
589  *
590  * RETURNS:
591  * True if the mode was set successfully, or false otherwise.
592  */
593 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
594                               struct drm_display_mode *mode,
595                               int x, int y,
596                               struct drm_framebuffer *old_fb)
597 {
598         struct drm_device *dev = crtc->dev;
599         struct drm_display_mode *adjusted_mode, saved_mode;
600         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
601         struct drm_encoder_helper_funcs *encoder_funcs;
602         int saved_x, saved_y;
603         struct drm_encoder *encoder;
604         bool ret = true;
605
606         adjusted_mode = drm_mode_duplicate(dev, mode);
607
608         crtc->enabled = drm_helper_crtc_in_use(crtc);
609
610         if (!crtc->enabled)
611                 return true;
612
613         saved_mode = crtc->mode;
614         saved_x = crtc->x;
615         saved_y = crtc->y;
616
617         /* Update crtc values up front so the driver can rely on them for mode
618          * setting.
619          */
620         crtc->mode = *mode;
621         crtc->x = x;
622         crtc->y = y;
623
624         /* Pass our mode to the connectors and the CRTC to give them a chance to
625          * adjust it according to limitations or connector properties, and also
626          * a chance to reject the mode entirely.
627          */
628         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
629
630                 if (encoder->crtc != crtc)
631                         continue;
632                 encoder_funcs = encoder->helper_private;
633                 if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
634                                                       adjusted_mode))) {
635                         goto done;
636                 }
637         }
638
639         if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {
640                 goto done;
641         }
642
643         /* Prepare the encoders and CRTCs before setting the mode. */
644         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
645
646                 if (encoder->crtc != crtc)
647                         continue;
648                 encoder_funcs = encoder->helper_private;
649                 /* Disable the encoders as the first thing we do. */
650                 encoder_funcs->prepare(encoder);
651         }
652
653         drm_crtc_prepare_encoders(dev);
654
655         crtc_funcs->prepare(crtc);
656
657         /* Set up the DPLL and any encoders state that needs to adjust or depend
658          * on the DPLL.
659          */
660         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
661         if (!ret)
662             goto done;
663
664         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
665
666                 if (encoder->crtc != crtc)
667                         continue;
668
669                 DRM_INFO("%s: set mode %s %x\n", drm_get_encoder_name(encoder),
670                          mode->name, mode->base.id);
671                 encoder_funcs = encoder->helper_private;
672                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
673         }
674
675         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
676         crtc_funcs->commit(crtc);
677
678         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
679
680                 if (encoder->crtc != crtc)
681                         continue;
682
683                 encoder_funcs = encoder->helper_private;
684                 encoder_funcs->commit(encoder);
685
686         }
687
688         /* XXX free adjustedmode */
689         drm_mode_destroy(dev, adjusted_mode);
690         /* FIXME: add subpixel order */
691 done:
692         if (!ret) {
693                 crtc->mode = saved_mode;
694                 crtc->x = saved_x;
695                 crtc->y = saved_y;
696         }
697
698         return ret;
699 }
700 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
701
702
703 /**
704  * drm_crtc_helper_set_config - set a new config from userspace
705  * @crtc: CRTC to setup
706  * @crtc_info: user provided configuration
707  * @new_mode: new mode to set
708  * @connector_set: set of connectors for the new config
709  * @fb: new framebuffer
710  *
711  * LOCKING:
712  * Caller must hold mode config lock.
713  *
714  * Setup a new configuration, provided by the user in @crtc_info, and enable
715  * it.
716  *
717  * RETURNS:
718  * Zero. (FIXME)
719  */
720 int drm_crtc_helper_set_config(struct drm_mode_set *set)
721 {
722         struct drm_device *dev;
723         struct drm_crtc *save_crtcs, *new_crtc, *crtc;
724         struct drm_encoder *save_encoders, *new_encoder, *encoder;
725         struct drm_framebuffer *old_fb = NULL;
726         bool mode_changed = false; /* if true do a full mode set */
727         bool fb_changed = false; /* if true and !mode_changed just do a flip */
728         struct drm_connector *save_connectors, *connector;
729         int count = 0, ro, fail = 0;
730         struct drm_crtc_helper_funcs *crtc_funcs;
731         int ret = 0;
732
733         DRM_DEBUG_KMS("\n");
734
735         if (!set)
736                 return -EINVAL;
737
738         if (!set->crtc)
739                 return -EINVAL;
740
741         if (!set->crtc->helper_private)
742                 return -EINVAL;
743
744         crtc_funcs = set->crtc->helper_private;
745
746         DRM_DEBUG_KMS("crtc: %p %d fb: %p connectors: %p num_connectors:"
747                         " %d (x, y) (%i, %i)\n",
748                   set->crtc, set->crtc->base.id, set->fb, set->connectors,
749                   (int)set->num_connectors, set->x, set->y);
750
751         dev = set->crtc->dev;
752
753         /* Allocate space for the backup of all (non-pointer) crtc, encoder and
754          * connector data. */
755         save_crtcs = kzalloc(dev->mode_config.num_crtc *
756                              sizeof(struct drm_crtc), GFP_KERNEL);
757         if (!save_crtcs)
758                 return -ENOMEM;
759
760         save_encoders = kzalloc(dev->mode_config.num_encoder *
761                                 sizeof(struct drm_encoder), GFP_KERNEL);
762         if (!save_encoders) {
763                 kfree(save_crtcs);
764                 return -ENOMEM;
765         }
766
767         save_connectors = kzalloc(dev->mode_config.num_connector *
768                                 sizeof(struct drm_connector), GFP_KERNEL);
769         if (!save_connectors) {
770                 kfree(save_crtcs);
771                 kfree(save_encoders);
772                 return -ENOMEM;
773         }
774
775         /* Copy data. Note that driver private data is not affected.
776          * Should anything bad happen only the expected state is
777          * restored, not the drivers personal bookkeeping.
778          */
779         count = 0;
780         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
781                 save_crtcs[count++] = *crtc;
782         }
783
784         count = 0;
785         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
786                 save_encoders[count++] = *encoder;
787         }
788
789         count = 0;
790         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
791                 save_connectors[count++] = *connector;
792         }
793
794         /* We should be able to check here if the fb has the same properties
795          * and then just flip_or_move it */
796         if (set->crtc->fb != set->fb) {
797                 /* If we have no fb then treat it as a full mode set */
798                 if (set->crtc->fb == NULL) {
799                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
800                         mode_changed = true;
801                 } else if (set->fb == NULL) {
802                         mode_changed = true;
803                 } else if ((set->fb->bits_per_pixel !=
804                          set->crtc->fb->bits_per_pixel) ||
805                          set->fb->depth != set->crtc->fb->depth)
806                         fb_changed = true;
807                 else
808                         fb_changed = true;
809         }
810
811         if (set->x != set->crtc->x || set->y != set->crtc->y)
812                 fb_changed = true;
813
814         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
815                 DRM_DEBUG_KMS("modes are different, full mode set\n");
816                 drm_mode_debug_printmodeline(&set->crtc->mode);
817                 drm_mode_debug_printmodeline(set->mode);
818                 mode_changed = true;
819         }
820
821         /* a) traverse passed in connector list and get encoders for them */
822         count = 0;
823         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
824                 struct drm_connector_helper_funcs *connector_funcs =
825                         connector->helper_private;
826                 new_encoder = connector->encoder;
827                 for (ro = 0; ro < set->num_connectors; ro++) {
828                         if (set->connectors[ro] == connector) {
829                                 new_encoder = connector_funcs->best_encoder(connector);
830                                 /* if we can't get an encoder for a connector
831                                    we are setting now - then fail */
832                                 if (new_encoder == NULL)
833                                         /* don't break so fail path works correct */
834                                         fail = 1;
835                                 break;
836                         }
837                 }
838
839                 if (new_encoder != connector->encoder) {
840                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
841                         mode_changed = true;
842                         /* If the encoder is reused for another connector, then
843                          * the appropriate crtc will be set later.
844                          */
845                         if (connector->encoder)
846                                 connector->encoder->crtc = NULL;
847                         connector->encoder = new_encoder;
848                 }
849         }
850
851         if (fail) {
852                 ret = -EINVAL;
853                 goto fail;
854         }
855
856         count = 0;
857         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
858                 if (!connector->encoder)
859                         continue;
860
861                 if (connector->encoder->crtc == set->crtc)
862                         new_crtc = NULL;
863                 else
864                         new_crtc = connector->encoder->crtc;
865
866                 for (ro = 0; ro < set->num_connectors; ro++) {
867                         if (set->connectors[ro] == connector)
868                                 new_crtc = set->crtc;
869                 }
870
871                 /* Make sure the new CRTC will work with the encoder */
872                 if (new_crtc &&
873                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
874                         ret = -EINVAL;
875                         goto fail;
876                 }
877                 if (new_crtc != connector->encoder->crtc) {
878                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
879                         mode_changed = true;
880                         connector->encoder->crtc = new_crtc;
881                 }
882                 DRM_DEBUG_KMS("setting connector %d crtc to %p\n",
883                           connector->base.id, new_crtc);
884         }
885
886         /* mode_set_base is not a required function */
887         if (fb_changed && !crtc_funcs->mode_set_base)
888                 mode_changed = true;
889
890         if (mode_changed) {
891                 old_fb = set->crtc->fb;
892                 set->crtc->fb = set->fb;
893                 set->crtc->enabled = (set->mode != NULL);
894                 if (set->mode != NULL) {
895                         DRM_DEBUG_KMS("attempting to set mode from"
896                                         " userspace\n");
897                         drm_mode_debug_printmodeline(set->mode);
898                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
899                                                       set->x, set->y,
900                                                       old_fb)) {
901                                 DRM_ERROR("failed to set mode on crtc %p\n",
902                                           set->crtc);
903                                 ret = -EINVAL;
904                                 goto fail;
905                         }
906                         /* TODO are these needed? */
907                         set->crtc->desired_x = set->x;
908                         set->crtc->desired_y = set->y;
909                         set->crtc->desired_mode = set->mode;
910                 }
911                 drm_helper_disable_unused_functions(dev);
912         } else if (fb_changed) {
913                 old_fb = set->crtc->fb;
914                 if (set->crtc->fb != set->fb)
915                         set->crtc->fb = set->fb;
916                 ret = crtc_funcs->mode_set_base(set->crtc,
917                                                 set->x, set->y, old_fb);
918                 if (ret != 0)
919                         goto fail;
920         }
921
922         kfree(save_connectors);
923         kfree(save_encoders);
924         kfree(save_crtcs);
925         return 0;
926
927 fail:
928         /* Restore all previous data. */
929         count = 0;
930         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
931                 *crtc = save_crtcs[count++];
932         }
933
934         count = 0;
935         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
936                 *encoder = save_encoders[count++];
937         }
938
939         count = 0;
940         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
941                 *connector = save_connectors[count++];
942         }
943
944         kfree(save_connectors);
945         kfree(save_encoders);
946         kfree(save_crtcs);
947         return ret;
948 }
949 EXPORT_SYMBOL(drm_crtc_helper_set_config);
950
951 bool drm_helper_plugged_event(struct drm_device *dev)
952 {
953         DRM_DEBUG_KMS("\n");
954
955         drm_helper_probe_connector_modes(dev, dev->mode_config.max_width,
956                                          dev->mode_config.max_height);
957
958         drm_setup_crtcs(dev);
959
960         /* alert the driver fb layer */
961         dev->mode_config.funcs->fb_changed(dev);
962
963         /* FIXME: send hotplug event */
964         return true;
965 }
966 /**
967  * drm_initial_config - setup a sane initial connector configuration
968  * @dev: DRM device
969  *
970  * LOCKING:
971  * Called at init time, must take mode config lock.
972  *
973  * Scan the CRTCs and connectors and try to put together an initial setup.
974  * At the moment, this is a cloned configuration across all heads with
975  * a new framebuffer object as the backing store.
976  *
977  * RETURNS:
978  * Zero if everything went ok, nonzero otherwise.
979  */
980 bool drm_helper_initial_config(struct drm_device *dev)
981 {
982         struct drm_connector *connector;
983         int count = 0;
984
985         count = drm_helper_probe_connector_modes(dev,
986                                                  dev->mode_config.max_width,
987                                                  dev->mode_config.max_height);
988
989         /*
990          * None of the available connectors had any modes, so add some
991          * and try to light them up anyway
992          */
993         if (!count) {
994                 DRM_ERROR("connectors have no modes, using standard modes\n");
995                 list_for_each_entry(connector,
996                                     &dev->mode_config.connector_list,
997                                     head)
998                         drm_helper_add_std_modes(dev, connector);
999         }
1000
1001         drm_setup_crtcs(dev);
1002
1003         /* alert the driver fb layer */
1004         dev->mode_config.funcs->fb_changed(dev);
1005
1006         return 0;
1007 }
1008 EXPORT_SYMBOL(drm_helper_initial_config);
1009
1010 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
1011 {
1012         int dpms = DRM_MODE_DPMS_OFF;
1013         struct drm_connector *connector;
1014         struct drm_device *dev = encoder->dev;
1015
1016         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
1017                 if (connector->encoder == encoder)
1018                         if (connector->dpms < dpms)
1019                                 dpms = connector->dpms;
1020         return dpms;
1021 }
1022
1023 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
1024 {
1025         int dpms = DRM_MODE_DPMS_OFF;
1026         struct drm_connector *connector;
1027         struct drm_device *dev = crtc->dev;
1028
1029         list_for_each_entry(connector, &dev->mode_config.connector_list, head)
1030                 if (connector->encoder && connector->encoder->crtc == crtc)
1031                         if (connector->dpms < dpms)
1032                                 dpms = connector->dpms;
1033         return dpms;
1034 }
1035
1036 /**
1037  * drm_helper_connector_dpms
1038  * @connector affected connector
1039  * @mode DPMS mode
1040  *
1041  * Calls the low-level connector DPMS function, then
1042  * calls appropriate encoder and crtc DPMS functions as well
1043  */
1044 void drm_helper_connector_dpms(struct drm_connector *connector, int mode)
1045 {
1046         struct drm_encoder *encoder = connector->encoder;
1047         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
1048         int old_dpms;
1049
1050         if (mode == connector->dpms)
1051                 return;
1052
1053         old_dpms = connector->dpms;
1054         connector->dpms = mode;
1055
1056         /* from off to on, do crtc then encoder */
1057         if (mode < old_dpms) {
1058                 if (crtc) {
1059                         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1060                         if (crtc_funcs->dpms)
1061                                 (*crtc_funcs->dpms) (crtc,
1062                                                      drm_helper_choose_crtc_dpms(crtc));
1063                 }
1064                 if (encoder) {
1065                         struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
1066                         if (encoder_funcs->dpms)
1067                                 (*encoder_funcs->dpms) (encoder,
1068                                                         drm_helper_choose_encoder_dpms(encoder));
1069                 }
1070         }
1071
1072         /* from on to off, do encoder then crtc */
1073         if (mode > old_dpms) {
1074                 if (encoder) {
1075                         struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
1076                         if (encoder_funcs->dpms)
1077                                 (*encoder_funcs->dpms) (encoder,
1078                                                         drm_helper_choose_encoder_dpms(encoder));
1079                 }
1080                 if (crtc) {
1081                         struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1082                         if (crtc_funcs->dpms)
1083                                 (*crtc_funcs->dpms) (crtc,
1084                                                      drm_helper_choose_crtc_dpms(crtc));
1085                 }
1086         }
1087
1088         return;
1089 }
1090 EXPORT_SYMBOL(drm_helper_connector_dpms);
1091
1092 /**
1093  * drm_hotplug_stage_two
1094  * @dev DRM device
1095  * @connector hotpluged connector
1096  *
1097  * LOCKING.
1098  * Caller must hold mode config lock, function might grab struct lock.
1099  *
1100  * Stage two of a hotplug.
1101  *
1102  * RETURNS:
1103  * Zero on success, errno on failure.
1104  */
1105 int drm_helper_hotplug_stage_two(struct drm_device *dev)
1106 {
1107         drm_helper_plugged_event(dev);
1108
1109         return 0;
1110 }
1111 EXPORT_SYMBOL(drm_helper_hotplug_stage_two);
1112
1113 int drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
1114                                    struct drm_mode_fb_cmd *mode_cmd)
1115 {
1116         fb->width = mode_cmd->width;
1117         fb->height = mode_cmd->height;
1118         fb->pitch = mode_cmd->pitch;
1119         fb->bits_per_pixel = mode_cmd->bpp;
1120         fb->depth = mode_cmd->depth;
1121
1122         return 0;
1123 }
1124 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
1125
1126 int drm_helper_resume_force_mode(struct drm_device *dev)
1127 {
1128         struct drm_crtc *crtc;
1129         int ret;
1130
1131         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
1132
1133                 if (!crtc->enabled)
1134                         continue;
1135
1136                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
1137                                                crtc->x, crtc->y, crtc->fb);
1138
1139                 if (ret == false)
1140                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
1141         }
1142         /* disable the unused connectors while restoring the modesetting */
1143         drm_helper_disable_unused_functions(dev);
1144         return 0;
1145 }
1146 EXPORT_SYMBOL(drm_helper_resume_force_mode);