nrelease - fix/improve livecd
[dragonfly.git] / sys / dev / 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 <linux/kernel.h>
33 #include <linux/export.h>
34 #include <linux/moduleparam.h>
35
36 #include <drm/drmP.h>
37 #include <drm/drm_atomic.h>
38 #include <drm/drm_crtc.h>
39 #include <drm/drm_encoder.h>
40 #include <drm/drm_fourcc.h>
41 #include <drm/drm_crtc_helper.h>
42 #include <drm/drm_fb_helper.h>
43 #include <drm/drm_plane_helper.h>
44 #include <drm/drm_atomic_helper.h>
45 #include <drm/drm_edid.h>
46
47 /**
48  * DOC: overview
49  *
50  * The CRTC modeset helper library provides a default set_config implementation
51  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
52  * the same callbacks which drivers can use to e.g. restore the modeset
53  * configuration on resume with drm_helper_resume_force_mode().
54  *
55  * Note that this helper library doesn't track the current power state of CRTCs
56  * and encoders. It can call callbacks like &drm_encoder_helper_funcs.dpms even
57  * though the hardware is already in the desired state. This deficiency has been
58  * fixed in the atomic helpers.
59  *
60  * The driver callbacks are mostly compatible with the atomic modeset helpers,
61  * except for the handling of the primary plane: Atomic helpers require that the
62  * primary plane is implemented as a real standalone plane and not directly tied
63  * to the CRTC state. For easier transition this library provides functions to
64  * implement the old semantics required by the CRTC helpers using the new plane
65  * and atomic helper callbacks.
66  *
67  * Drivers are strongly urged to convert to the atomic helpers (by way of first
68  * converting to the plane helpers). New drivers must not use these functions
69  * but need to implement the atomic interface instead, potentially using the
70  * atomic helpers for that.
71  *
72  * These legacy modeset helpers use the same function table structures as
73  * all other modesetting helpers. See the documentation for struct
74  * &drm_crtc_helper_funcs, &struct drm_encoder_helper_funcs and struct
75  * &drm_connector_helper_funcs.
76  */
77
78 /**
79  * drm_helper_encoder_in_use - check if a given encoder is in use
80  * @encoder: encoder to check
81  *
82  * Checks whether @encoder is with the current mode setting output configuration
83  * in use by any connector. This doesn't mean that it is actually enabled since
84  * the DPMS state is tracked separately.
85  *
86  * Returns:
87  * True if @encoder is used, false otherwise.
88  */
89 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
90 {
91         struct drm_connector *connector;
92         struct drm_connector_list_iter conn_iter;
93         struct drm_device *dev = encoder->dev;
94
95         /*
96          * We can expect this mutex to be locked if we are not panicking.
97          * Locking is currently fubar in the panic handler.
98          */
99         if (!oops_in_progress) {
100                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
101                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
102         }
103
104
105         drm_connector_list_iter_begin(dev, &conn_iter);
106         drm_for_each_connector_iter(connector, &conn_iter) {
107                 if (connector->encoder == encoder) {
108                         drm_connector_list_iter_end(&conn_iter);
109                         return true;
110                 }
111         }
112         drm_connector_list_iter_end(&conn_iter);
113         return false;
114 }
115 EXPORT_SYMBOL(drm_helper_encoder_in_use);
116
117 /**
118  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
119  * @crtc: CRTC to check
120  *
121  * Checks whether @crtc is with the current mode setting output configuration
122  * in use by any connector. This doesn't mean that it is actually enabled since
123  * the DPMS state is tracked separately.
124  *
125  * Returns:
126  * True if @crtc is used, false otherwise.
127  */
128 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
129 {
130         struct drm_encoder *encoder;
131         struct drm_device *dev = crtc->dev;
132
133         /*
134          * We can expect this mutex to be locked if we are not panicking.
135          * Locking is currently fubar in the panic handler.
136          */
137         if (!oops_in_progress)
138                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
139
140         drm_for_each_encoder(encoder, dev)
141                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
142                         return true;
143         return false;
144 }
145 EXPORT_SYMBOL(drm_helper_crtc_in_use);
146
147 static void
148 drm_encoder_disable(struct drm_encoder *encoder)
149 {
150         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
151
152         if (!encoder_funcs)
153                 return;
154
155         drm_bridge_disable(encoder->bridge);
156
157         if (encoder_funcs->disable)
158                 (*encoder_funcs->disable)(encoder);
159         else if (encoder_funcs->dpms)
160                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
161
162         drm_bridge_post_disable(encoder->bridge);
163 }
164
165 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
166 {
167         struct drm_encoder *encoder;
168         struct drm_crtc *crtc;
169
170         drm_warn_on_modeset_not_all_locked(dev);
171
172         drm_for_each_encoder(encoder, dev) {
173                 if (!drm_helper_encoder_in_use(encoder)) {
174                         drm_encoder_disable(encoder);
175                         /* disconnect encoder from any connector */
176                         encoder->crtc = NULL;
177                 }
178         }
179
180         drm_for_each_crtc(crtc, dev) {
181                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
182                 crtc->enabled = drm_helper_crtc_in_use(crtc);
183                 if (!crtc->enabled) {
184                         if (crtc_funcs->disable)
185                                 (*crtc_funcs->disable)(crtc);
186                         else
187                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
188                         crtc->primary->fb = NULL;
189                 }
190         }
191 }
192
193 /**
194  * drm_helper_disable_unused_functions - disable unused objects
195  * @dev: DRM device
196  *
197  * This function walks through the entire mode setting configuration of @dev. It
198  * will remove any CRTC links of unused encoders and encoder links of
199  * disconnected connectors. Then it will disable all unused encoders and CRTCs
200  * either by calling their disable callback if available or by calling their
201  * dpms callback with DRM_MODE_DPMS_OFF.
202  *
203  * NOTE:
204  *
205  * This function is part of the legacy modeset helper library and will cause
206  * major confusion with atomic drivers. This is because atomic helpers guarantee
207  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
208  * on an enabled functions. drm_helper_disable_unused_functions() on the other
209  * hand throws such guarantees into the wind and calls disable hooks
210  * unconditionally on unused functions.
211  */
212 void drm_helper_disable_unused_functions(struct drm_device *dev)
213 {
214         if (drm_core_check_feature(dev, DRIVER_ATOMIC))
215                 DRM_ERROR("Called for atomic driver, this is not what you want.\n");
216
217         drm_modeset_lock_all(dev);
218         __drm_helper_disable_unused_functions(dev);
219         drm_modeset_unlock_all(dev);
220 }
221 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
222
223 /*
224  * Check the CRTC we're going to map each output to vs. its current
225  * CRTC.  If they don't match, we have to disable the output and the CRTC
226  * since the driver will have to re-route things.
227  */
228 static void
229 drm_crtc_prepare_encoders(struct drm_device *dev)
230 {
231         const struct drm_encoder_helper_funcs *encoder_funcs;
232         struct drm_encoder *encoder;
233
234         drm_for_each_encoder(encoder, dev) {
235                 encoder_funcs = encoder->helper_private;
236                 if (!encoder_funcs)
237                         continue;
238
239                 /* Disable unused encoders */
240                 if (encoder->crtc == NULL)
241                         drm_encoder_disable(encoder);
242                 /* Disable encoders whose CRTC is about to change */
243                 if (encoder_funcs->get_crtc &&
244                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
245                         drm_encoder_disable(encoder);
246         }
247 }
248
249 /**
250  * drm_crtc_helper_set_mode - internal helper to set a mode
251  * @crtc: CRTC to program
252  * @mode: mode to use
253  * @x: horizontal offset into the surface
254  * @y: vertical offset into the surface
255  * @old_fb: old framebuffer, for cleanup
256  *
257  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
258  * to fixup or reject the mode prior to trying to set it. This is an internal
259  * helper that drivers could e.g. use to update properties that require the
260  * entire output pipe to be disabled and re-enabled in a new configuration. For
261  * example for changing whether audio is enabled on a hdmi link or for changing
262  * panel fitter or dither attributes. It is also called by the
263  * drm_crtc_helper_set_config() helper function to drive the mode setting
264  * sequence.
265  *
266  * Returns:
267  * True if the mode was set successfully, false otherwise.
268  */
269 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
270                               struct drm_display_mode *mode,
271                               int x, int y,
272                               struct drm_framebuffer *old_fb)
273 {
274         struct drm_device *dev = crtc->dev;
275         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
276         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
277         const struct drm_encoder_helper_funcs *encoder_funcs;
278         int saved_x, saved_y;
279         bool saved_enabled;
280         struct drm_encoder *encoder;
281         bool ret = true;
282
283         drm_warn_on_modeset_not_all_locked(dev);
284
285         saved_enabled = crtc->enabled;
286         crtc->enabled = drm_helper_crtc_in_use(crtc);
287         if (!crtc->enabled)
288                 return true;
289
290         adjusted_mode = drm_mode_duplicate(dev, mode);
291         if (!adjusted_mode) {
292                 crtc->enabled = saved_enabled;
293                 return false;
294         }
295
296         saved_mode = crtc->mode;
297         saved_hwmode = crtc->hwmode;
298         saved_x = crtc->x;
299         saved_y = crtc->y;
300
301         /* Update crtc values up front so the driver can rely on them for mode
302          * setting.
303          */
304         crtc->mode = *mode;
305         crtc->x = x;
306         crtc->y = y;
307
308         /* Pass our mode to the connectors and the CRTC to give them a chance to
309          * adjust it according to limitations or connector properties, and also
310          * a chance to reject the mode entirely.
311          */
312         drm_for_each_encoder(encoder, dev) {
313
314                 if (encoder->crtc != crtc)
315                         continue;
316
317                 encoder_funcs = encoder->helper_private;
318                 if (!encoder_funcs)
319                         continue;
320
321                 ret = drm_bridge_mode_fixup(encoder->bridge,
322                         mode, adjusted_mode);
323                 if (!ret) {
324                         DRM_DEBUG_KMS("Bridge fixup failed\n");
325                         goto done;
326                 }
327
328                 encoder_funcs = encoder->helper_private;
329                 if (encoder_funcs->mode_fixup) {
330                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
331                                                               adjusted_mode))) {
332                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
333                                 goto done;
334                         }
335                 }
336         }
337
338         if (crtc_funcs->mode_fixup) {
339                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
340                                                 adjusted_mode))) {
341                         DRM_DEBUG_KMS("CRTC fixup failed\n");
342                         goto done;
343                 }
344         }
345         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
346
347         crtc->hwmode = *adjusted_mode;
348
349         /* Prepare the encoders and CRTCs before setting the mode. */
350         drm_for_each_encoder(encoder, dev) {
351
352                 if (encoder->crtc != crtc)
353                         continue;
354
355                 encoder_funcs = encoder->helper_private;
356                 if (!encoder_funcs)
357                         continue;
358
359                 drm_bridge_disable(encoder->bridge);
360
361                 /* Disable the encoders as the first thing we do. */
362                 if (encoder_funcs->prepare)
363                         encoder_funcs->prepare(encoder);
364
365                 drm_bridge_post_disable(encoder->bridge);
366         }
367
368         drm_crtc_prepare_encoders(dev);
369
370         crtc_funcs->prepare(crtc);
371
372         /* Set up the DPLL and any encoders state that needs to adjust or depend
373          * on the DPLL.
374          */
375         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
376         if (!ret)
377             goto done;
378
379         drm_for_each_encoder(encoder, dev) {
380
381                 if (encoder->crtc != crtc)
382                         continue;
383
384                 encoder_funcs = encoder->helper_private;
385                 if (!encoder_funcs)
386                         continue;
387
388                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
389                         encoder->base.id, encoder->name,
390                         mode->base.id, mode->name);
391                 if (encoder_funcs->mode_set)
392                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
393
394                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
395         }
396
397         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
398         crtc_funcs->commit(crtc);
399
400         drm_for_each_encoder(encoder, dev) {
401
402                 if (encoder->crtc != crtc)
403                         continue;
404
405                 encoder_funcs = encoder->helper_private;
406                 if (!encoder_funcs)
407                         continue;
408
409                 drm_bridge_pre_enable(encoder->bridge);
410
411                 if (encoder_funcs->commit)
412                         encoder_funcs->commit(encoder);
413
414                 drm_bridge_enable(encoder->bridge);
415         }
416
417         /* Calculate and store various constants which
418          * are later needed by vblank and swap-completion
419          * timestamping. They are derived from true hwmode.
420          */
421         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
422
423         /* FIXME: add subpixel order */
424 done:
425         drm_mode_destroy(dev, adjusted_mode);
426         if (!ret) {
427                 crtc->enabled = saved_enabled;
428                 crtc->mode = saved_mode;
429                 crtc->hwmode = saved_hwmode;
430                 crtc->x = saved_x;
431                 crtc->y = saved_y;
432         }
433
434         return ret;
435 }
436 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
437
438 static void
439 drm_crtc_helper_disable(struct drm_crtc *crtc)
440 {
441         struct drm_device *dev = crtc->dev;
442         struct drm_connector *connector;
443         struct drm_encoder *encoder;
444
445         /* Decouple all encoders and their attached connectors from this crtc */
446         drm_for_each_encoder(encoder, dev) {
447                 struct drm_connector_list_iter conn_iter;
448
449                 if (encoder->crtc != crtc)
450                         continue;
451
452                 drm_connector_list_iter_begin(dev, &conn_iter);
453                 drm_for_each_connector_iter(connector, &conn_iter) {
454                         if (connector->encoder != encoder)
455                                 continue;
456
457                         connector->encoder = NULL;
458
459                         /*
460                          * drm_helper_disable_unused_functions() ought to be
461                          * doing this, but since we've decoupled the encoder
462                          * from the connector above, the required connection
463                          * between them is henceforth no longer available.
464                          */
465                         connector->dpms = DRM_MODE_DPMS_OFF;
466
467                         /* we keep a reference while the encoder is bound */
468                         drm_connector_put(connector);
469                 }
470                 drm_connector_list_iter_end(&conn_iter);
471         }
472
473         __drm_helper_disable_unused_functions(dev);
474 }
475
476 /**
477  * drm_crtc_helper_set_config - set a new config from userspace
478  * @set: mode set configuration
479  * @ctx: lock acquire context, not used here
480  *
481  * The drm_crtc_helper_set_config() helper function implements the of
482  * &drm_crtc_funcs.set_config callback for drivers using the legacy CRTC
483  * helpers.
484  *
485  * It first tries to locate the best encoder for each connector by calling the
486  * connector @drm_connector_helper_funcs.best_encoder helper operation.
487  *
488  * After locating the appropriate encoders, the helper function will call the
489  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
490  * or reject it completely in which case an error will be returned to the
491  * application. If the new configuration after mode adjustment is identical to
492  * the current configuration the helper function will return without performing
493  * any other operation.
494  *
495  * If the adjusted mode is identical to the current mode but changes to the
496  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
497  * will call the CRTC &drm_crtc_helper_funcs.mode_set_base helper operation.
498  *
499  * If the adjusted mode differs from the current mode, or if the
500  * ->mode_set_base() helper operation is not provided, the helper function
501  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
502  * and ->commit() CRTC and encoder helper operations, in that order.
503  * Alternatively it can also use the dpms and disable helper operations. For
504  * details see &struct drm_crtc_helper_funcs and struct
505  * &drm_encoder_helper_funcs.
506  *
507  * This function is deprecated.  New drivers must implement atomic modeset
508  * support, for which this function is unsuitable. Instead drivers should use
509  * drm_atomic_helper_set_config().
510  *
511  * Returns:
512  * Returns 0 on success, negative errno numbers on failure.
513  */
514 int drm_crtc_helper_set_config(struct drm_mode_set *set,
515                                struct drm_modeset_acquire_ctx *ctx)
516 {
517         struct drm_device *dev;
518         struct drm_crtc **save_encoder_crtcs, *new_crtc;
519         struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
520         bool mode_changed = false; /* if true do a full mode set */
521         bool fb_changed = false; /* if true and !mode_changed just do a flip */
522         struct drm_connector *connector;
523         struct drm_connector_list_iter conn_iter;
524         int count = 0, ro, fail = 0;
525         const struct drm_crtc_helper_funcs *crtc_funcs;
526         struct drm_mode_set save_set;
527         int ret;
528         int i;
529
530         DRM_DEBUG_KMS("\n");
531
532         BUG_ON(!set);
533         BUG_ON(!set->crtc);
534         BUG_ON(!set->crtc->helper_private);
535
536         /* Enforce sane interface api - has been abused by the fb helper. */
537         BUG_ON(!set->mode && set->fb);
538         BUG_ON(set->fb && set->num_connectors == 0);
539
540         crtc_funcs = set->crtc->helper_private;
541
542         if (!set->mode)
543                 set->fb = NULL;
544
545         if (set->fb) {
546                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
547                               set->crtc->base.id, set->crtc->name,
548                               set->fb->base.id,
549                               (int)set->num_connectors, set->x, set->y);
550         } else {
551                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
552                               set->crtc->base.id, set->crtc->name);
553                 drm_crtc_helper_disable(set->crtc);
554                 return 0;
555         }
556
557         dev = set->crtc->dev;
558
559         drm_warn_on_modeset_not_all_locked(dev);
560
561         /*
562          * Allocate space for the backup of all (non-pointer) encoder and
563          * connector data.
564          */
565         save_encoder_crtcs = kcalloc(dev->mode_config.num_encoder,
566                                 sizeof(struct drm_crtc *), GFP_KERNEL);
567         if (!save_encoder_crtcs)
568                 return -ENOMEM;
569
570         save_connector_encoders = kcalloc(dev->mode_config.num_connector,
571                                 sizeof(struct drm_encoder *), GFP_KERNEL);
572         if (!save_connector_encoders) {
573                 kfree(save_encoder_crtcs);
574                 return -ENOMEM;
575         }
576
577         /*
578          * Copy data. Note that driver private data is not affected.
579          * Should anything bad happen only the expected state is
580          * restored, not the drivers personal bookkeeping.
581          */
582         count = 0;
583         drm_for_each_encoder(encoder, dev) {
584                 save_encoder_crtcs[count++] = encoder->crtc;
585         }
586
587         count = 0;
588         drm_connector_list_iter_begin(dev, &conn_iter);
589         drm_for_each_connector_iter(connector, &conn_iter)
590                 save_connector_encoders[count++] = connector->encoder;
591         drm_connector_list_iter_end(&conn_iter);
592
593         save_set.crtc = set->crtc;
594         save_set.mode = &set->crtc->mode;
595         save_set.x = set->crtc->x;
596         save_set.y = set->crtc->y;
597         save_set.fb = set->crtc->primary->fb;
598
599         /* We should be able to check here if the fb has the same properties
600          * and then just flip_or_move it */
601         if (set->crtc->primary->fb != set->fb) {
602                 /* If we have no fb then treat it as a full mode set */
603                 if (set->crtc->primary->fb == NULL) {
604                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
605                         mode_changed = true;
606                 } else if (set->fb->format != set->crtc->primary->fb->format) {
607                         mode_changed = true;
608                 } else
609                         fb_changed = true;
610         }
611
612         if (set->x != set->crtc->x || set->y != set->crtc->y)
613                 fb_changed = true;
614
615         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
616                 DRM_DEBUG_KMS("modes are different, full mode set\n");
617                 drm_mode_debug_printmodeline(&set->crtc->mode);
618                 drm_mode_debug_printmodeline(set->mode);
619                 mode_changed = true;
620         }
621
622         /* take a reference on all unbound connectors in set, reuse the
623          * already taken reference for bound connectors
624          */
625         for (ro = 0; ro < set->num_connectors; ro++) {
626                 if (set->connectors[ro]->encoder)
627                         continue;
628                 drm_connector_get(set->connectors[ro]);
629         }
630
631         /* a) traverse passed in connector list and get encoders for them */
632         count = 0;
633         drm_connector_list_iter_begin(dev, &conn_iter);
634         drm_for_each_connector_iter(connector, &conn_iter) {
635                 const struct drm_connector_helper_funcs *connector_funcs =
636                         connector->helper_private;
637                 new_encoder = connector->encoder;
638                 for (ro = 0; ro < set->num_connectors; ro++) {
639                         if (set->connectors[ro] == connector) {
640                                 new_encoder = connector_funcs->best_encoder(connector);
641                                 /* if we can't get an encoder for a connector
642                                    we are setting now - then fail */
643                                 if (new_encoder == NULL)
644                                         /* don't break so fail path works correct */
645                                         fail = 1;
646
647                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
648                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
649                                         mode_changed = true;
650                                 }
651
652                                 break;
653                         }
654                 }
655
656                 if (new_encoder != connector->encoder) {
657                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
658                         mode_changed = true;
659                         /* If the encoder is reused for another connector, then
660                          * the appropriate crtc will be set later.
661                          */
662                         if (connector->encoder)
663                                 connector->encoder->crtc = NULL;
664                         connector->encoder = new_encoder;
665                 }
666         }
667         drm_connector_list_iter_end(&conn_iter);
668
669         if (fail) {
670                 ret = -EINVAL;
671                 goto fail;
672         }
673
674         count = 0;
675         drm_connector_list_iter_begin(dev, &conn_iter);
676         drm_for_each_connector_iter(connector, &conn_iter) {
677                 if (!connector->encoder)
678                         continue;
679
680                 if (connector->encoder->crtc == set->crtc)
681                         new_crtc = NULL;
682                 else
683                         new_crtc = connector->encoder->crtc;
684
685                 for (ro = 0; ro < set->num_connectors; ro++) {
686                         if (set->connectors[ro] == connector)
687                                 new_crtc = set->crtc;
688                 }
689
690                 /* Make sure the new CRTC will work with the encoder */
691                 if (new_crtc &&
692                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
693                         ret = -EINVAL;
694                         drm_connector_list_iter_end(&conn_iter);
695                         goto fail;
696                 }
697                 if (new_crtc != connector->encoder->crtc) {
698                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
699                         mode_changed = true;
700                         connector->encoder->crtc = new_crtc;
701                 }
702                 if (new_crtc) {
703                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
704                                       connector->base.id, connector->name,
705                                       new_crtc->base.id, new_crtc->name);
706                 } else {
707                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
708                                       connector->base.id, connector->name);
709                 }
710         }
711         drm_connector_list_iter_end(&conn_iter);
712
713         /* mode_set_base is not a required function */
714         if (fb_changed && !crtc_funcs->mode_set_base)
715                 mode_changed = true;
716
717         if (mode_changed) {
718                 if (drm_helper_crtc_in_use(set->crtc)) {
719                         DRM_DEBUG_KMS("attempting to set mode from"
720                                         " userspace\n");
721                         drm_mode_debug_printmodeline(set->mode);
722                         set->crtc->primary->fb = set->fb;
723                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
724                                                       set->x, set->y,
725                                                       save_set.fb)) {
726                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
727                                           set->crtc->base.id, set->crtc->name);
728                                 set->crtc->primary->fb = save_set.fb;
729                                 ret = -EINVAL;
730                                 goto fail;
731                         }
732                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
733                         for (i = 0; i < set->num_connectors; i++) {
734                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
735                                               set->connectors[i]->name);
736                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
737                         }
738                 }
739                 __drm_helper_disable_unused_functions(dev);
740         } else if (fb_changed) {
741                 set->crtc->x = set->x;
742                 set->crtc->y = set->y;
743                 set->crtc->primary->fb = set->fb;
744                 ret = crtc_funcs->mode_set_base(set->crtc,
745                                                 set->x, set->y, save_set.fb);
746                 if (ret != 0) {
747                         set->crtc->x = save_set.x;
748                         set->crtc->y = save_set.y;
749                         set->crtc->primary->fb = save_set.fb;
750                         goto fail;
751                 }
752         }
753
754         kfree(save_connector_encoders);
755         kfree(save_encoder_crtcs);
756         return 0;
757
758 fail:
759         /* Restore all previous data. */
760         count = 0;
761         drm_for_each_encoder(encoder, dev) {
762                 encoder->crtc = save_encoder_crtcs[count++];
763         }
764
765         count = 0;
766         drm_connector_list_iter_begin(dev, &conn_iter);
767         drm_for_each_connector_iter(connector, &conn_iter)
768                 connector->encoder = save_connector_encoders[count++];
769         drm_connector_list_iter_end(&conn_iter);
770
771         /* after fail drop reference on all unbound connectors in set, let
772          * bound connectors keep their reference
773          */
774         for (ro = 0; ro < set->num_connectors; ro++) {
775                 if (set->connectors[ro]->encoder)
776                         continue;
777                 drm_connector_put(set->connectors[ro]);
778         }
779
780         /* Try to restore the config */
781         if (mode_changed &&
782             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
783                                       save_set.y, save_set.fb))
784                 DRM_ERROR("failed to restore config after modeset failure\n");
785
786         kfree(save_connector_encoders);
787         kfree(save_encoder_crtcs);
788         return ret;
789 }
790 EXPORT_SYMBOL(drm_crtc_helper_set_config);
791
792 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
793 {
794         int dpms = DRM_MODE_DPMS_OFF;
795         struct drm_connector *connector;
796         struct drm_connector_list_iter conn_iter;
797         struct drm_device *dev = encoder->dev;
798
799         drm_connector_list_iter_begin(dev, &conn_iter);
800         drm_for_each_connector_iter(connector, &conn_iter)
801                 if (connector->encoder == encoder)
802                         if (connector->dpms < dpms)
803                                 dpms = connector->dpms;
804         drm_connector_list_iter_end(&conn_iter);
805
806         return dpms;
807 }
808
809 /* Helper which handles bridge ordering around encoder dpms */
810 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
811 {
812         struct drm_bridge *bridge = encoder->bridge;
813         const struct drm_encoder_helper_funcs *encoder_funcs;
814
815         encoder_funcs = encoder->helper_private;
816         if (!encoder_funcs)
817                 return;
818
819         if (mode == DRM_MODE_DPMS_ON)
820                 drm_bridge_pre_enable(bridge);
821         else
822                 drm_bridge_disable(bridge);
823
824         if (encoder_funcs->dpms)
825                 encoder_funcs->dpms(encoder, mode);
826
827         if (mode == DRM_MODE_DPMS_ON)
828                 drm_bridge_enable(bridge);
829         else
830                 drm_bridge_post_disable(bridge);
831 }
832
833 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
834 {
835         int dpms = DRM_MODE_DPMS_OFF;
836         struct drm_connector *connector;
837         struct drm_connector_list_iter conn_iter;
838         struct drm_device *dev = crtc->dev;
839
840         drm_connector_list_iter_begin(dev, &conn_iter);
841         drm_for_each_connector_iter(connector, &conn_iter)
842                 if (connector->encoder && connector->encoder->crtc == crtc)
843                         if (connector->dpms < dpms)
844                                 dpms = connector->dpms;
845         drm_connector_list_iter_end(&conn_iter);
846
847         return dpms;
848 }
849
850 /**
851  * drm_helper_connector_dpms() - connector dpms helper implementation
852  * @connector: affected connector
853  * @mode: DPMS mode
854  *
855  * The drm_helper_connector_dpms() helper function implements the
856  * &drm_connector_funcs.dpms callback for drivers using the legacy CRTC
857  * helpers.
858  *
859  * This is the main helper function provided by the CRTC helper framework for
860  * implementing the DPMS connector attribute. It computes the new desired DPMS
861  * state for all encoders and CRTCs in the output mesh and calls the
862  * &drm_crtc_helper_funcs.dpms and &drm_encoder_helper_funcs.dpms callbacks
863  * provided by the driver.
864  *
865  * This function is deprecated.  New drivers must implement atomic modeset
866  * support, where DPMS is handled in the DRM core.
867  *
868  * Returns:
869  * Always returns 0.
870  */
871 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
872 {
873         struct drm_encoder *encoder = connector->encoder;
874         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
875         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
876
877         if (mode == connector->dpms)
878                 return 0;
879
880         old_dpms = connector->dpms;
881         connector->dpms = mode;
882
883         if (encoder)
884                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
885
886         /* from off to on, do crtc then encoder */
887         if (mode < old_dpms) {
888                 if (crtc) {
889                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
890                         if (crtc_funcs->dpms)
891                                 (*crtc_funcs->dpms) (crtc,
892                                                      drm_helper_choose_crtc_dpms(crtc));
893                 }
894                 if (encoder)
895                         drm_helper_encoder_dpms(encoder, encoder_dpms);
896         }
897
898         /* from on to off, do encoder then crtc */
899         if (mode > old_dpms) {
900                 if (encoder)
901                         drm_helper_encoder_dpms(encoder, encoder_dpms);
902                 if (crtc) {
903                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
904                         if (crtc_funcs->dpms)
905                                 (*crtc_funcs->dpms) (crtc,
906                                                      drm_helper_choose_crtc_dpms(crtc));
907                 }
908         }
909
910         return 0;
911 }
912 EXPORT_SYMBOL(drm_helper_connector_dpms);
913
914 /**
915  * drm_helper_resume_force_mode - force-restore mode setting configuration
916  * @dev: drm_device which should be restored
917  *
918  * Drivers which use the mode setting helpers can use this function to
919  * force-restore the mode setting configuration e.g. on resume or when something
920  * else might have trampled over the hw state (like some overzealous old BIOSen
921  * tended to do).
922  *
923  * This helper doesn't provide a error return value since restoring the old
924  * config should never fail due to resource allocation issues since the driver
925  * has successfully set the restored configuration already. Hence this should
926  * boil down to the equivalent of a few dpms on calls, which also don't provide
927  * an error code.
928  *
929  * Drivers where simply restoring an old configuration again might fail (e.g.
930  * due to slight differences in allocating shared resources when the
931  * configuration is restored in a different order than when userspace set it up)
932  * need to use their own restore logic.
933  *
934  * This function is deprecated. New drivers should implement atomic mode-
935  * setting and use the atomic suspend/resume helpers.
936  *
937  * See also:
938  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
939  */
940 void drm_helper_resume_force_mode(struct drm_device *dev)
941 {
942         struct drm_crtc *crtc;
943         struct drm_encoder *encoder;
944         const struct drm_crtc_helper_funcs *crtc_funcs;
945         int encoder_dpms;
946         bool ret;
947
948         drm_modeset_lock_all(dev);
949         drm_for_each_crtc(crtc, dev) {
950
951                 if (!crtc->enabled)
952                         continue;
953
954                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
955                                                crtc->x, crtc->y, crtc->primary->fb);
956
957                 /* Restoring the old config should never fail! */
958                 if (ret == false)
959                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
960
961                 /* Turn off outputs that were already powered off */
962                 if (drm_helper_choose_crtc_dpms(crtc)) {
963                         drm_for_each_encoder(encoder, dev) {
964
965                                 if(encoder->crtc != crtc)
966                                         continue;
967
968                                 encoder_dpms = drm_helper_choose_encoder_dpms(
969                                                         encoder);
970
971                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
972                         }
973
974                         crtc_funcs = crtc->helper_private;
975                         if (crtc_funcs->dpms)
976                                 (*crtc_funcs->dpms) (crtc,
977                                                      drm_helper_choose_crtc_dpms(crtc));
978                 }
979         }
980
981         /* disable the unused connectors while restoring the modesetting */
982         __drm_helper_disable_unused_functions(dev);
983         drm_modeset_unlock_all(dev);
984 }
985 EXPORT_SYMBOL(drm_helper_resume_force_mode);
986
987 /**
988  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
989  * @crtc: DRM CRTC
990  * @mode: DRM display mode which userspace requested
991  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
992  * @x: x offset of the CRTC scanout area on the underlying framebuffer
993  * @y: y offset of the CRTC scanout area on the underlying framebuffer
994  * @old_fb: previous framebuffer
995  *
996  * This function implements a callback useable as the ->mode_set callback
997  * required by the CRTC helpers. Besides the atomic plane helper functions for
998  * the primary plane the driver must also provide the ->mode_set_nofb callback
999  * to set up the CRTC.
1000  *
1001  * This is a transitional helper useful for converting drivers to the atomic
1002  * interfaces.
1003  */
1004 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
1005                              struct drm_display_mode *adjusted_mode, int x, int y,
1006                              struct drm_framebuffer *old_fb)
1007 {
1008         struct drm_crtc_state *crtc_state;
1009         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1010         int ret;
1011
1012         if (crtc->funcs->atomic_duplicate_state)
1013                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
1014         else {
1015                 if (!crtc->state)
1016                         drm_atomic_helper_crtc_reset(crtc);
1017
1018                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
1019         }
1020
1021         if (!crtc_state)
1022                 return -ENOMEM;
1023
1024         crtc_state->planes_changed = true;
1025         crtc_state->mode_changed = true;
1026         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
1027         if (ret)
1028                 goto out;
1029         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1030
1031         if (crtc_funcs->atomic_check) {
1032                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1033                 if (ret)
1034                         goto out;
1035         }
1036
1037         swap(crtc->state, crtc_state);
1038
1039         crtc_funcs->mode_set_nofb(crtc);
1040
1041         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1042
1043 out:
1044         if (crtc_state) {
1045                 if (crtc->funcs->atomic_destroy_state)
1046                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1047                 else
1048                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1049         }
1050
1051         return ret;
1052 }
1053 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1054
1055 /**
1056  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1057  * @crtc: DRM CRTC
1058  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1059  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1060  * @old_fb: previous framebuffer
1061  *
1062  * This function implements a callback useable as the ->mode_set_base used
1063  * required by the CRTC helpers. The driver must provide the atomic plane helper
1064  * functions for the primary plane.
1065  *
1066  * This is a transitional helper useful for converting drivers to the atomic
1067  * interfaces.
1068  */
1069 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1070                                   struct drm_framebuffer *old_fb)
1071 {
1072         struct drm_plane_state *plane_state;
1073         struct drm_plane *plane = crtc->primary;
1074
1075         if (plane->funcs->atomic_duplicate_state)
1076                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1077         else {
1078                 if (!plane->state)
1079                         drm_atomic_helper_plane_reset(plane);
1080
1081                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1082         }
1083         if (!plane_state)
1084                 return -ENOMEM;
1085         plane_state->plane = plane;
1086
1087         plane_state->crtc = crtc;
1088         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1089         plane_state->crtc_x = 0;
1090         plane_state->crtc_y = 0;
1091         plane_state->crtc_h = crtc->mode.vdisplay;
1092         plane_state->crtc_w = crtc->mode.hdisplay;
1093         plane_state->src_x = x << 16;
1094         plane_state->src_y = y << 16;
1095         plane_state->src_h = crtc->mode.vdisplay << 16;
1096         plane_state->src_w = crtc->mode.hdisplay << 16;
1097
1098         return drm_plane_helper_commit(plane, plane_state, old_fb);
1099 }
1100 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);