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Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-block
[karo-tx-linux.git] / 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 <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_fourcc.h>
40 #include <drm/drm_crtc_helper.h>
41 #include <drm/drm_fb_helper.h>
42 #include <drm/drm_plane_helper.h>
43 #include <drm/drm_atomic_helper.h>
44 #include <drm/drm_edid.h>
45
46 /**
47  * DOC: overview
48  *
49  * The CRTC modeset helper library provides a default set_config implementation
50  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
51  * the same callbacks which drivers can use to e.g. restore the modeset
52  * configuration on resume with drm_helper_resume_force_mode().
53  *
54  * Note that this helper library doesn't track the current power state of CRTCs
55  * and encoders. It can call callbacks like ->dpms() even though the hardware is
56  * already in the desired state. This deficiency has been fixed in the atomic
57  * helpers.
58  *
59  * The driver callbacks are mostly compatible with the atomic modeset helpers,
60  * except for the handling of the primary plane: Atomic helpers require that the
61  * primary plane is implemented as a real standalone plane and not directly tied
62  * to the CRTC state. For easier transition this library provides functions to
63  * implement the old semantics required by the CRTC helpers using the new plane
64  * and atomic helper callbacks.
65  *
66  * Drivers are strongly urged to convert to the atomic helpers (by way of first
67  * converting to the plane helpers). New drivers must not use these functions
68  * but need to implement the atomic interface instead, potentially using the
69  * atomic helpers for that.
70  *
71  * These legacy modeset helpers use the same function table structures as
72  * all other modesetting helpers. See the documentation for struct
73  * &drm_crtc_helper_funcs, struct &drm_encoder_helper_funcs and struct
74  * &drm_connector_helper_funcs.
75  */
76
77 /**
78  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
79  *                                              connector list
80  * @dev: drm device to operate on
81  *
82  * Some userspace presumes that the first connected connector is the main
83  * display, where it's supposed to display e.g. the login screen. For
84  * laptops, this should be the main panel. Use this function to sort all
85  * (eDP/LVDS) panels to the front of the connector list, instead of
86  * painstakingly trying to initialize them in the right order.
87  */
88 void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
89 {
90         struct drm_connector *connector, *tmp;
91         struct list_head panel_list;
92
93         INIT_LIST_HEAD(&panel_list);
94
95         list_for_each_entry_safe(connector, tmp,
96                                  &dev->mode_config.connector_list, head) {
97                 if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
98                     connector->connector_type == DRM_MODE_CONNECTOR_eDP)
99                         list_move_tail(&connector->head, &panel_list);
100         }
101
102         list_splice(&panel_list, &dev->mode_config.connector_list);
103 }
104 EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
105
106 /**
107  * drm_helper_encoder_in_use - check if a given encoder is in use
108  * @encoder: encoder to check
109  *
110  * Checks whether @encoder is with the current mode setting output configuration
111  * in use by any connector. This doesn't mean that it is actually enabled since
112  * the DPMS state is tracked separately.
113  *
114  * Returns:
115  * True if @encoder is used, false otherwise.
116  */
117 bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
118 {
119         struct drm_connector *connector;
120         struct drm_device *dev = encoder->dev;
121
122         /*
123          * We can expect this mutex to be locked if we are not panicking.
124          * Locking is currently fubar in the panic handler.
125          */
126         if (!oops_in_progress) {
127                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
128                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
129         }
130
131         drm_for_each_connector(connector, dev)
132                 if (connector->encoder == encoder)
133                         return true;
134         return false;
135 }
136 EXPORT_SYMBOL(drm_helper_encoder_in_use);
137
138 /**
139  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
140  * @crtc: CRTC to check
141  *
142  * Checks whether @crtc is with the current mode setting output configuration
143  * in use by any connector. This doesn't mean that it is actually enabled since
144  * the DPMS state is tracked separately.
145  *
146  * Returns:
147  * True if @crtc is used, false otherwise.
148  */
149 bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
150 {
151         struct drm_encoder *encoder;
152         struct drm_device *dev = crtc->dev;
153
154         /*
155          * We can expect this mutex to be locked if we are not panicking.
156          * Locking is currently fubar in the panic handler.
157          */
158         if (!oops_in_progress)
159                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
160
161         drm_for_each_encoder(encoder, dev)
162                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
163                         return true;
164         return false;
165 }
166 EXPORT_SYMBOL(drm_helper_crtc_in_use);
167
168 static void
169 drm_encoder_disable(struct drm_encoder *encoder)
170 {
171         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
172
173         if (!encoder_funcs)
174                 return;
175
176         drm_bridge_disable(encoder->bridge);
177
178         if (encoder_funcs->disable)
179                 (*encoder_funcs->disable)(encoder);
180         else if (encoder_funcs->dpms)
181                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
182
183         drm_bridge_post_disable(encoder->bridge);
184 }
185
186 static void __drm_helper_disable_unused_functions(struct drm_device *dev)
187 {
188         struct drm_encoder *encoder;
189         struct drm_crtc *crtc;
190
191         drm_warn_on_modeset_not_all_locked(dev);
192
193         drm_for_each_encoder(encoder, dev) {
194                 if (!drm_helper_encoder_in_use(encoder)) {
195                         drm_encoder_disable(encoder);
196                         /* disconnect encoder from any connector */
197                         encoder->crtc = NULL;
198                 }
199         }
200
201         drm_for_each_crtc(crtc, dev) {
202                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
203                 crtc->enabled = drm_helper_crtc_in_use(crtc);
204                 if (!crtc->enabled) {
205                         if (crtc_funcs->disable)
206                                 (*crtc_funcs->disable)(crtc);
207                         else
208                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
209                         crtc->primary->fb = NULL;
210                 }
211         }
212 }
213
214 /**
215  * drm_helper_disable_unused_functions - disable unused objects
216  * @dev: DRM device
217  *
218  * This function walks through the entire mode setting configuration of @dev. It
219  * will remove any CRTC links of unused encoders and encoder links of
220  * disconnected connectors. Then it will disable all unused encoders and CRTCs
221  * either by calling their disable callback if available or by calling their
222  * dpms callback with DRM_MODE_DPMS_OFF.
223  *
224  * NOTE:
225  *
226  * This function is part of the legacy modeset helper library and will cause
227  * major confusion with atomic drivers. This is because atomic helpers guarantee
228  * to never call ->disable() hooks on a disabled function, or ->enable() hooks
229  * on an enabled functions. drm_helper_disable_unused_functions() on the other
230  * hand throws such guarantees into the wind and calls disable hooks
231  * unconditionally on unused functions.
232  */
233 void drm_helper_disable_unused_functions(struct drm_device *dev)
234 {
235         drm_modeset_lock_all(dev);
236         __drm_helper_disable_unused_functions(dev);
237         drm_modeset_unlock_all(dev);
238 }
239 EXPORT_SYMBOL(drm_helper_disable_unused_functions);
240
241 /*
242  * Check the CRTC we're going to map each output to vs. its current
243  * CRTC.  If they don't match, we have to disable the output and the CRTC
244  * since the driver will have to re-route things.
245  */
246 static void
247 drm_crtc_prepare_encoders(struct drm_device *dev)
248 {
249         const struct drm_encoder_helper_funcs *encoder_funcs;
250         struct drm_encoder *encoder;
251
252         drm_for_each_encoder(encoder, dev) {
253                 encoder_funcs = encoder->helper_private;
254                 if (!encoder_funcs)
255                         continue;
256
257                 /* Disable unused encoders */
258                 if (encoder->crtc == NULL)
259                         drm_encoder_disable(encoder);
260                 /* Disable encoders whose CRTC is about to change */
261                 if (encoder_funcs->get_crtc &&
262                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
263                         drm_encoder_disable(encoder);
264         }
265 }
266
267 /**
268  * drm_crtc_helper_set_mode - internal helper to set a mode
269  * @crtc: CRTC to program
270  * @mode: mode to use
271  * @x: horizontal offset into the surface
272  * @y: vertical offset into the surface
273  * @old_fb: old framebuffer, for cleanup
274  *
275  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
276  * to fixup or reject the mode prior to trying to set it. This is an internal
277  * helper that drivers could e.g. use to update properties that require the
278  * entire output pipe to be disabled and re-enabled in a new configuration. For
279  * example for changing whether audio is enabled on a hdmi link or for changing
280  * panel fitter or dither attributes. It is also called by the
281  * drm_crtc_helper_set_config() helper function to drive the mode setting
282  * sequence.
283  *
284  * Returns:
285  * True if the mode was set successfully, false otherwise.
286  */
287 bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
288                               struct drm_display_mode *mode,
289                               int x, int y,
290                               struct drm_framebuffer *old_fb)
291 {
292         struct drm_device *dev = crtc->dev;
293         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
294         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
295         const struct drm_encoder_helper_funcs *encoder_funcs;
296         int saved_x, saved_y;
297         bool saved_enabled;
298         struct drm_encoder *encoder;
299         bool ret = true;
300
301         drm_warn_on_modeset_not_all_locked(dev);
302
303         saved_enabled = crtc->enabled;
304         crtc->enabled = drm_helper_crtc_in_use(crtc);
305         if (!crtc->enabled)
306                 return true;
307
308         adjusted_mode = drm_mode_duplicate(dev, mode);
309         if (!adjusted_mode) {
310                 crtc->enabled = saved_enabled;
311                 return false;
312         }
313
314         saved_mode = crtc->mode;
315         saved_hwmode = crtc->hwmode;
316         saved_x = crtc->x;
317         saved_y = crtc->y;
318
319         /* Update crtc values up front so the driver can rely on them for mode
320          * setting.
321          */
322         crtc->mode = *mode;
323         crtc->x = x;
324         crtc->y = y;
325
326         /* Pass our mode to the connectors and the CRTC to give them a chance to
327          * adjust it according to limitations or connector properties, and also
328          * a chance to reject the mode entirely.
329          */
330         drm_for_each_encoder(encoder, dev) {
331
332                 if (encoder->crtc != crtc)
333                         continue;
334
335                 encoder_funcs = encoder->helper_private;
336                 if (!encoder_funcs)
337                         continue;
338
339                 ret = drm_bridge_mode_fixup(encoder->bridge,
340                         mode, adjusted_mode);
341                 if (!ret) {
342                         DRM_DEBUG_KMS("Bridge fixup failed\n");
343                         goto done;
344                 }
345
346                 encoder_funcs = encoder->helper_private;
347                 if (encoder_funcs->mode_fixup) {
348                         if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
349                                                               adjusted_mode))) {
350                                 DRM_DEBUG_KMS("Encoder fixup failed\n");
351                                 goto done;
352                         }
353                 }
354         }
355
356         if (crtc_funcs->mode_fixup) {
357                 if (!(ret = crtc_funcs->mode_fixup(crtc, mode,
358                                                 adjusted_mode))) {
359                         DRM_DEBUG_KMS("CRTC fixup failed\n");
360                         goto done;
361                 }
362         }
363         DRM_DEBUG_KMS("[CRTC:%d:%s]\n", crtc->base.id, crtc->name);
364
365         crtc->hwmode = *adjusted_mode;
366
367         /* Prepare the encoders and CRTCs before setting the mode. */
368         drm_for_each_encoder(encoder, dev) {
369
370                 if (encoder->crtc != crtc)
371                         continue;
372
373                 encoder_funcs = encoder->helper_private;
374                 if (!encoder_funcs)
375                         continue;
376
377                 drm_bridge_disable(encoder->bridge);
378
379                 /* Disable the encoders as the first thing we do. */
380                 if (encoder_funcs->prepare)
381                         encoder_funcs->prepare(encoder);
382
383                 drm_bridge_post_disable(encoder->bridge);
384         }
385
386         drm_crtc_prepare_encoders(dev);
387
388         crtc_funcs->prepare(crtc);
389
390         /* Set up the DPLL and any encoders state that needs to adjust or depend
391          * on the DPLL.
392          */
393         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
394         if (!ret)
395             goto done;
396
397         drm_for_each_encoder(encoder, dev) {
398
399                 if (encoder->crtc != crtc)
400                         continue;
401
402                 encoder_funcs = encoder->helper_private;
403                 if (!encoder_funcs)
404                         continue;
405
406                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
407                         encoder->base.id, encoder->name,
408                         mode->base.id, mode->name);
409                 if (encoder_funcs->mode_set)
410                         encoder_funcs->mode_set(encoder, mode, adjusted_mode);
411
412                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
413         }
414
415         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
416         crtc_funcs->commit(crtc);
417
418         drm_for_each_encoder(encoder, dev) {
419
420                 if (encoder->crtc != crtc)
421                         continue;
422
423                 encoder_funcs = encoder->helper_private;
424                 if (!encoder_funcs)
425                         continue;
426
427                 drm_bridge_pre_enable(encoder->bridge);
428
429                 if (encoder_funcs->commit)
430                         encoder_funcs->commit(encoder);
431
432                 drm_bridge_enable(encoder->bridge);
433         }
434
435         /* Calculate and store various constants which
436          * are later needed by vblank and swap-completion
437          * timestamping. They are derived from true hwmode.
438          */
439         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
440
441         /* FIXME: add subpixel order */
442 done:
443         drm_mode_destroy(dev, adjusted_mode);
444         if (!ret) {
445                 crtc->enabled = saved_enabled;
446                 crtc->mode = saved_mode;
447                 crtc->hwmode = saved_hwmode;
448                 crtc->x = saved_x;
449                 crtc->y = saved_y;
450         }
451
452         return ret;
453 }
454 EXPORT_SYMBOL(drm_crtc_helper_set_mode);
455
456 static void
457 drm_crtc_helper_disable(struct drm_crtc *crtc)
458 {
459         struct drm_device *dev = crtc->dev;
460         struct drm_connector *connector;
461         struct drm_encoder *encoder;
462
463         /* Decouple all encoders and their attached connectors from this crtc */
464         drm_for_each_encoder(encoder, dev) {
465                 if (encoder->crtc != crtc)
466                         continue;
467
468                 drm_for_each_connector(connector, dev) {
469                         if (connector->encoder != encoder)
470                                 continue;
471
472                         connector->encoder = NULL;
473
474                         /*
475                          * drm_helper_disable_unused_functions() ought to be
476                          * doing this, but since we've decoupled the encoder
477                          * from the connector above, the required connection
478                          * between them is henceforth no longer available.
479                          */
480                         connector->dpms = DRM_MODE_DPMS_OFF;
481
482                         /* we keep a reference while the encoder is bound */
483                         drm_connector_unreference(connector);
484                 }
485         }
486
487         __drm_helper_disable_unused_functions(dev);
488 }
489
490 /**
491  * drm_crtc_helper_set_config - set a new config from userspace
492  * @set: mode set configuration
493  *
494  * The drm_crtc_helper_set_config() helper function implements the set_config
495  * callback of struct &drm_crtc_funcs for drivers using the legacy CRTC helpers.
496  *
497  * It first tries to locate the best encoder for each connector by calling the
498  * connector ->best_encoder() (struct &drm_connector_helper_funcs) helper
499  * operation.
500  *
501  * After locating the appropriate encoders, the helper function will call the
502  * mode_fixup encoder and CRTC helper operations to adjust the requested mode,
503  * or reject it completely in which case an error will be returned to the
504  * application. If the new configuration after mode adjustment is identical to
505  * the current configuration the helper function will return without performing
506  * any other operation.
507  *
508  * If the adjusted mode is identical to the current mode but changes to the
509  * frame buffer need to be applied, the drm_crtc_helper_set_config() function
510  * will call the CRTC ->mode_set_base() (struct &drm_crtc_helper_funcs) helper
511  * operation.
512  *
513  * If the adjusted mode differs from the current mode, or if the
514  * ->mode_set_base() helper operation is not provided, the helper function
515  * performs a full mode set sequence by calling the ->prepare(), ->mode_set()
516  * and ->commit() CRTC and encoder helper operations, in that order.
517  * Alternatively it can also use the dpms and disable helper operations. For
518  * details see struct &drm_crtc_helper_funcs and struct
519  * &drm_encoder_helper_funcs.
520  *
521  * This function is deprecated.  New drivers must implement atomic modeset
522  * support, for which this function is unsuitable. Instead drivers should use
523  * drm_atomic_helper_set_config().
524  *
525  * Returns:
526  * Returns 0 on success, negative errno numbers on failure.
527  */
528 int drm_crtc_helper_set_config(struct drm_mode_set *set)
529 {
530         struct drm_device *dev;
531         struct drm_crtc **save_encoder_crtcs, *new_crtc;
532         struct drm_encoder **save_connector_encoders, *new_encoder, *encoder;
533         bool mode_changed = false; /* if true do a full mode set */
534         bool fb_changed = false; /* if true and !mode_changed just do a flip */
535         struct drm_connector *connector;
536         int count = 0, ro, fail = 0;
537         const struct drm_crtc_helper_funcs *crtc_funcs;
538         struct drm_mode_set save_set;
539         int ret;
540         int i;
541
542         DRM_DEBUG_KMS("\n");
543
544         BUG_ON(!set);
545         BUG_ON(!set->crtc);
546         BUG_ON(!set->crtc->helper_private);
547
548         /* Enforce sane interface api - has been abused by the fb helper. */
549         BUG_ON(!set->mode && set->fb);
550         BUG_ON(set->fb && set->num_connectors == 0);
551
552         crtc_funcs = set->crtc->helper_private;
553
554         if (!set->mode)
555                 set->fb = NULL;
556
557         if (set->fb) {
558                 DRM_DEBUG_KMS("[CRTC:%d:%s] [FB:%d] #connectors=%d (x y) (%i %i)\n",
559                               set->crtc->base.id, set->crtc->name,
560                               set->fb->base.id,
561                               (int)set->num_connectors, set->x, set->y);
562         } else {
563                 DRM_DEBUG_KMS("[CRTC:%d:%s] [NOFB]\n",
564                               set->crtc->base.id, set->crtc->name);
565                 drm_crtc_helper_disable(set->crtc);
566                 return 0;
567         }
568
569         dev = set->crtc->dev;
570
571         drm_warn_on_modeset_not_all_locked(dev);
572
573         /*
574          * Allocate space for the backup of all (non-pointer) encoder and
575          * connector data.
576          */
577         save_encoder_crtcs = kzalloc(dev->mode_config.num_encoder *
578                                 sizeof(struct drm_crtc *), GFP_KERNEL);
579         if (!save_encoder_crtcs)
580                 return -ENOMEM;
581
582         save_connector_encoders = kzalloc(dev->mode_config.num_connector *
583                                 sizeof(struct drm_encoder *), GFP_KERNEL);
584         if (!save_connector_encoders) {
585                 kfree(save_encoder_crtcs);
586                 return -ENOMEM;
587         }
588
589         /*
590          * Copy data. Note that driver private data is not affected.
591          * Should anything bad happen only the expected state is
592          * restored, not the drivers personal bookkeeping.
593          */
594         count = 0;
595         drm_for_each_encoder(encoder, dev) {
596                 save_encoder_crtcs[count++] = encoder->crtc;
597         }
598
599         count = 0;
600         drm_for_each_connector(connector, dev) {
601                 save_connector_encoders[count++] = connector->encoder;
602         }
603
604         save_set.crtc = set->crtc;
605         save_set.mode = &set->crtc->mode;
606         save_set.x = set->crtc->x;
607         save_set.y = set->crtc->y;
608         save_set.fb = set->crtc->primary->fb;
609
610         /* We should be able to check here if the fb has the same properties
611          * and then just flip_or_move it */
612         if (set->crtc->primary->fb != set->fb) {
613                 /* If we have no fb then treat it as a full mode set */
614                 if (set->crtc->primary->fb == NULL) {
615                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
616                         mode_changed = true;
617                 } else if (set->fb->pixel_format !=
618                            set->crtc->primary->fb->pixel_format) {
619                         mode_changed = true;
620                 } else
621                         fb_changed = true;
622         }
623
624         if (set->x != set->crtc->x || set->y != set->crtc->y)
625                 fb_changed = true;
626
627         if (!drm_mode_equal(set->mode, &set->crtc->mode)) {
628                 DRM_DEBUG_KMS("modes are different, full mode set\n");
629                 drm_mode_debug_printmodeline(&set->crtc->mode);
630                 drm_mode_debug_printmodeline(set->mode);
631                 mode_changed = true;
632         }
633
634         /* take a reference on all unbound connectors in set, reuse the
635          * already taken reference for bound connectors
636          */
637         for (ro = 0; ro < set->num_connectors; ro++) {
638                 if (set->connectors[ro]->encoder)
639                         continue;
640                 drm_connector_reference(set->connectors[ro]);
641         }
642
643         /* a) traverse passed in connector list and get encoders for them */
644         count = 0;
645         drm_for_each_connector(connector, dev) {
646                 const struct drm_connector_helper_funcs *connector_funcs =
647                         connector->helper_private;
648                 new_encoder = connector->encoder;
649                 for (ro = 0; ro < set->num_connectors; ro++) {
650                         if (set->connectors[ro] == connector) {
651                                 new_encoder = connector_funcs->best_encoder(connector);
652                                 /* if we can't get an encoder for a connector
653                                    we are setting now - then fail */
654                                 if (new_encoder == NULL)
655                                         /* don't break so fail path works correct */
656                                         fail = 1;
657
658                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
659                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
660                                         mode_changed = true;
661                                 }
662
663                                 break;
664                         }
665                 }
666
667                 if (new_encoder != connector->encoder) {
668                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
669                         mode_changed = true;
670                         /* If the encoder is reused for another connector, then
671                          * the appropriate crtc will be set later.
672                          */
673                         if (connector->encoder)
674                                 connector->encoder->crtc = NULL;
675                         connector->encoder = new_encoder;
676                 }
677         }
678
679         if (fail) {
680                 ret = -EINVAL;
681                 goto fail;
682         }
683
684         count = 0;
685         drm_for_each_connector(connector, dev) {
686                 if (!connector->encoder)
687                         continue;
688
689                 if (connector->encoder->crtc == set->crtc)
690                         new_crtc = NULL;
691                 else
692                         new_crtc = connector->encoder->crtc;
693
694                 for (ro = 0; ro < set->num_connectors; ro++) {
695                         if (set->connectors[ro] == connector)
696                                 new_crtc = set->crtc;
697                 }
698
699                 /* Make sure the new CRTC will work with the encoder */
700                 if (new_crtc &&
701                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
702                         ret = -EINVAL;
703                         goto fail;
704                 }
705                 if (new_crtc != connector->encoder->crtc) {
706                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
707                         mode_changed = true;
708                         connector->encoder->crtc = new_crtc;
709                 }
710                 if (new_crtc) {
711                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d:%s]\n",
712                                       connector->base.id, connector->name,
713                                       new_crtc->base.id, new_crtc->name);
714                 } else {
715                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
716                                       connector->base.id, connector->name);
717                 }
718         }
719
720         /* mode_set_base is not a required function */
721         if (fb_changed && !crtc_funcs->mode_set_base)
722                 mode_changed = true;
723
724         if (mode_changed) {
725                 if (drm_helper_crtc_in_use(set->crtc)) {
726                         DRM_DEBUG_KMS("attempting to set mode from"
727                                         " userspace\n");
728                         drm_mode_debug_printmodeline(set->mode);
729                         set->crtc->primary->fb = set->fb;
730                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
731                                                       set->x, set->y,
732                                                       save_set.fb)) {
733                                 DRM_ERROR("failed to set mode on [CRTC:%d:%s]\n",
734                                           set->crtc->base.id, set->crtc->name);
735                                 set->crtc->primary->fb = save_set.fb;
736                                 ret = -EINVAL;
737                                 goto fail;
738                         }
739                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
740                         for (i = 0; i < set->num_connectors; i++) {
741                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
742                                               set->connectors[i]->name);
743                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
744                         }
745                 }
746                 __drm_helper_disable_unused_functions(dev);
747         } else if (fb_changed) {
748                 set->crtc->x = set->x;
749                 set->crtc->y = set->y;
750                 set->crtc->primary->fb = set->fb;
751                 ret = crtc_funcs->mode_set_base(set->crtc,
752                                                 set->x, set->y, save_set.fb);
753                 if (ret != 0) {
754                         set->crtc->x = save_set.x;
755                         set->crtc->y = save_set.y;
756                         set->crtc->primary->fb = save_set.fb;
757                         goto fail;
758                 }
759         }
760
761         kfree(save_connector_encoders);
762         kfree(save_encoder_crtcs);
763         return 0;
764
765 fail:
766         /* Restore all previous data. */
767         count = 0;
768         drm_for_each_encoder(encoder, dev) {
769                 encoder->crtc = save_encoder_crtcs[count++];
770         }
771
772         count = 0;
773         drm_for_each_connector(connector, dev) {
774                 connector->encoder = save_connector_encoders[count++];
775         }
776
777         /* after fail drop reference on all unbound connectors in set, let
778          * bound connectors keep their reference
779          */
780         for (ro = 0; ro < set->num_connectors; ro++) {
781                 if (set->connectors[ro]->encoder)
782                         continue;
783                 drm_connector_unreference(set->connectors[ro]);
784         }
785
786         /* Try to restore the config */
787         if (mode_changed &&
788             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
789                                       save_set.y, save_set.fb))
790                 DRM_ERROR("failed to restore config after modeset failure\n");
791
792         kfree(save_connector_encoders);
793         kfree(save_encoder_crtcs);
794         return ret;
795 }
796 EXPORT_SYMBOL(drm_crtc_helper_set_config);
797
798 static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
799 {
800         int dpms = DRM_MODE_DPMS_OFF;
801         struct drm_connector *connector;
802         struct drm_device *dev = encoder->dev;
803
804         drm_for_each_connector(connector, dev)
805                 if (connector->encoder == encoder)
806                         if (connector->dpms < dpms)
807                                 dpms = connector->dpms;
808         return dpms;
809 }
810
811 /* Helper which handles bridge ordering around encoder dpms */
812 static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
813 {
814         struct drm_bridge *bridge = encoder->bridge;
815         const struct drm_encoder_helper_funcs *encoder_funcs;
816
817         encoder_funcs = encoder->helper_private;
818         if (!encoder_funcs)
819                 return;
820
821         if (mode == DRM_MODE_DPMS_ON)
822                 drm_bridge_pre_enable(bridge);
823         else
824                 drm_bridge_disable(bridge);
825
826         if (encoder_funcs->dpms)
827                 encoder_funcs->dpms(encoder, mode);
828
829         if (mode == DRM_MODE_DPMS_ON)
830                 drm_bridge_enable(bridge);
831         else
832                 drm_bridge_post_disable(bridge);
833 }
834
835 static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
836 {
837         int dpms = DRM_MODE_DPMS_OFF;
838         struct drm_connector *connector;
839         struct drm_device *dev = crtc->dev;
840
841         drm_for_each_connector(connector, dev)
842                 if (connector->encoder && connector->encoder->crtc == crtc)
843                         if (connector->dpms < dpms)
844                                 dpms = connector->dpms;
845         return dpms;
846 }
847
848 /**
849  * drm_helper_connector_dpms() - connector dpms helper implementation
850  * @connector: affected connector
851  * @mode: DPMS mode
852  *
853  * The drm_helper_connector_dpms() helper function implements the ->dpms()
854  * callback of struct &drm_connector_funcs for drivers using the legacy CRTC helpers.
855  *
856  * This is the main helper function provided by the CRTC helper framework for
857  * implementing the DPMS connector attribute. It computes the new desired DPMS
858  * state for all encoders and CRTCs in the output mesh and calls the ->dpms()
859  * callbacks provided by the driver in struct &drm_crtc_helper_funcs and struct
860  * &drm_encoder_helper_funcs appropriately.
861  *
862  * This function is deprecated.  New drivers must implement atomic modeset
863  * support, for which this function is unsuitable. Instead drivers should use
864  * drm_atomic_helper_connector_dpms().
865  *
866  * Returns:
867  * Always returns 0.
868  */
869 int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
870 {
871         struct drm_encoder *encoder = connector->encoder;
872         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
873         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
874
875         if (mode == connector->dpms)
876                 return 0;
877
878         old_dpms = connector->dpms;
879         connector->dpms = mode;
880
881         if (encoder)
882                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
883
884         /* from off to on, do crtc then encoder */
885         if (mode < old_dpms) {
886                 if (crtc) {
887                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
888                         if (crtc_funcs->dpms)
889                                 (*crtc_funcs->dpms) (crtc,
890                                                      drm_helper_choose_crtc_dpms(crtc));
891                 }
892                 if (encoder)
893                         drm_helper_encoder_dpms(encoder, encoder_dpms);
894         }
895
896         /* from on to off, do encoder then crtc */
897         if (mode > old_dpms) {
898                 if (encoder)
899                         drm_helper_encoder_dpms(encoder, encoder_dpms);
900                 if (crtc) {
901                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
902                         if (crtc_funcs->dpms)
903                                 (*crtc_funcs->dpms) (crtc,
904                                                      drm_helper_choose_crtc_dpms(crtc));
905                 }
906         }
907
908         return 0;
909 }
910 EXPORT_SYMBOL(drm_helper_connector_dpms);
911
912 /**
913  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
914  * @fb: drm_framebuffer object to fill out
915  * @mode_cmd: metadata from the userspace fb creation request
916  *
917  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
918  * metadata fields.
919  */
920 void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
921                                     const struct drm_mode_fb_cmd2 *mode_cmd)
922 {
923         int i;
924
925         fb->width = mode_cmd->width;
926         fb->height = mode_cmd->height;
927         for (i = 0; i < 4; i++) {
928                 fb->pitches[i] = mode_cmd->pitches[i];
929                 fb->offsets[i] = mode_cmd->offsets[i];
930                 fb->modifier[i] = mode_cmd->modifier[i];
931         }
932         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
933                                     &fb->bits_per_pixel);
934         fb->pixel_format = mode_cmd->pixel_format;
935         fb->flags = mode_cmd->flags;
936 }
937 EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
938
939 /**
940  * drm_helper_resume_force_mode - force-restore mode setting configuration
941  * @dev: drm_device which should be restored
942  *
943  * Drivers which use the mode setting helpers can use this function to
944  * force-restore the mode setting configuration e.g. on resume or when something
945  * else might have trampled over the hw state (like some overzealous old BIOSen
946  * tended to do).
947  *
948  * This helper doesn't provide a error return value since restoring the old
949  * config should never fail due to resource allocation issues since the driver
950  * has successfully set the restored configuration already. Hence this should
951  * boil down to the equivalent of a few dpms on calls, which also don't provide
952  * an error code.
953  *
954  * Drivers where simply restoring an old configuration again might fail (e.g.
955  * due to slight differences in allocating shared resources when the
956  * configuration is restored in a different order than when userspace set it up)
957  * need to use their own restore logic.
958  *
959  * This function is deprecated. New drivers should implement atomic mode-
960  * setting and use the atomic suspend/resume helpers.
961  *
962  * See also:
963  * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
964  */
965 void drm_helper_resume_force_mode(struct drm_device *dev)
966 {
967         struct drm_crtc *crtc;
968         struct drm_encoder *encoder;
969         const struct drm_crtc_helper_funcs *crtc_funcs;
970         int encoder_dpms;
971         bool ret;
972
973         drm_modeset_lock_all(dev);
974         drm_for_each_crtc(crtc, dev) {
975
976                 if (!crtc->enabled)
977                         continue;
978
979                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
980                                                crtc->x, crtc->y, crtc->primary->fb);
981
982                 /* Restoring the old config should never fail! */
983                 if (ret == false)
984                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
985
986                 /* Turn off outputs that were already powered off */
987                 if (drm_helper_choose_crtc_dpms(crtc)) {
988                         drm_for_each_encoder(encoder, dev) {
989
990                                 if(encoder->crtc != crtc)
991                                         continue;
992
993                                 encoder_dpms = drm_helper_choose_encoder_dpms(
994                                                         encoder);
995
996                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
997                         }
998
999                         crtc_funcs = crtc->helper_private;
1000                         if (crtc_funcs->dpms)
1001                                 (*crtc_funcs->dpms) (crtc,
1002                                                      drm_helper_choose_crtc_dpms(crtc));
1003                 }
1004         }
1005
1006         /* disable the unused connectors while restoring the modesetting */
1007         __drm_helper_disable_unused_functions(dev);
1008         drm_modeset_unlock_all(dev);
1009 }
1010 EXPORT_SYMBOL(drm_helper_resume_force_mode);
1011
1012 /**
1013  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
1014  * @crtc: DRM CRTC
1015  * @mode: DRM display mode which userspace requested
1016  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
1017  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1018  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1019  * @old_fb: previous framebuffer
1020  *
1021  * This function implements a callback useable as the ->mode_set callback
1022  * required by the CRTC helpers. Besides the atomic plane helper functions for
1023  * the primary plane the driver must also provide the ->mode_set_nofb callback
1024  * to set up the CRTC.
1025  *
1026  * This is a transitional helper useful for converting drivers to the atomic
1027  * interfaces.
1028  */
1029 int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
1030                              struct drm_display_mode *adjusted_mode, int x, int y,
1031                              struct drm_framebuffer *old_fb)
1032 {
1033         struct drm_crtc_state *crtc_state;
1034         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
1035         int ret;
1036
1037         if (crtc->funcs->atomic_duplicate_state)
1038                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
1039         else {
1040                 if (!crtc->state)
1041                         drm_atomic_helper_crtc_reset(crtc);
1042
1043                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
1044         }
1045
1046         if (!crtc_state)
1047                 return -ENOMEM;
1048
1049         crtc_state->planes_changed = true;
1050         crtc_state->mode_changed = true;
1051         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
1052         if (ret)
1053                 goto out;
1054         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
1055
1056         if (crtc_funcs->atomic_check) {
1057                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
1058                 if (ret)
1059                         goto out;
1060         }
1061
1062         swap(crtc->state, crtc_state);
1063
1064         crtc_funcs->mode_set_nofb(crtc);
1065
1066         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
1067
1068 out:
1069         if (crtc_state) {
1070                 if (crtc->funcs->atomic_destroy_state)
1071                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
1072                 else
1073                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
1074         }
1075
1076         return ret;
1077 }
1078 EXPORT_SYMBOL(drm_helper_crtc_mode_set);
1079
1080 /**
1081  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
1082  * @crtc: DRM CRTC
1083  * @x: x offset of the CRTC scanout area on the underlying framebuffer
1084  * @y: y offset of the CRTC scanout area on the underlying framebuffer
1085  * @old_fb: previous framebuffer
1086  *
1087  * This function implements a callback useable as the ->mode_set_base used
1088  * required by the CRTC helpers. The driver must provide the atomic plane helper
1089  * functions for the primary plane.
1090  *
1091  * This is a transitional helper useful for converting drivers to the atomic
1092  * interfaces.
1093  */
1094 int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
1095                                   struct drm_framebuffer *old_fb)
1096 {
1097         struct drm_plane_state *plane_state;
1098         struct drm_plane *plane = crtc->primary;
1099
1100         if (plane->funcs->atomic_duplicate_state)
1101                 plane_state = plane->funcs->atomic_duplicate_state(plane);
1102         else {
1103                 if (!plane->state)
1104                         drm_atomic_helper_plane_reset(plane);
1105
1106                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
1107         }
1108         if (!plane_state)
1109                 return -ENOMEM;
1110         plane_state->plane = plane;
1111
1112         plane_state->crtc = crtc;
1113         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
1114         plane_state->crtc_x = 0;
1115         plane_state->crtc_y = 0;
1116         plane_state->crtc_h = crtc->mode.vdisplay;
1117         plane_state->crtc_w = crtc->mode.hdisplay;
1118         plane_state->src_x = x << 16;
1119         plane_state->src_y = y << 16;
1120         plane_state->src_h = crtc->mode.vdisplay << 16;
1121         plane_state->src_w = crtc->mode.hdisplay << 16;
1122
1123         return drm_plane_helper_commit(plane, plane_state, old_fb);
1124 }
1125 EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);
1126
1127 /**
1128  * drm_helper_crtc_enable_color_mgmt - enable color management properties
1129  * @crtc: DRM CRTC
1130  * @degamma_lut_size: the size of the degamma lut (before CSC)
1131  * @gamma_lut_size: the size of the gamma lut (after CSC)
1132  *
1133  * This function lets the driver enable the color correction properties on a
1134  * CRTC. This includes 3 degamma, csc and gamma properties that userspace can
1135  * set and 2 size properties to inform the userspace of the lut sizes.
1136  */
1137 void drm_helper_crtc_enable_color_mgmt(struct drm_crtc *crtc,
1138                                        int degamma_lut_size,
1139                                        int gamma_lut_size)
1140 {
1141         struct drm_device *dev = crtc->dev;
1142         struct drm_mode_config *config = &dev->mode_config;
1143
1144         drm_object_attach_property(&crtc->base,
1145                                    config->degamma_lut_property, 0);
1146         drm_object_attach_property(&crtc->base,
1147                                    config->ctm_property, 0);
1148         drm_object_attach_property(&crtc->base,
1149                                    config->gamma_lut_property, 0);
1150
1151         drm_object_attach_property(&crtc->base,
1152                                    config->degamma_lut_size_property,
1153                                    degamma_lut_size);
1154         drm_object_attach_property(&crtc->base,
1155                                    config->gamma_lut_size_property,
1156                                    gamma_lut_size);
1157 }
1158 EXPORT_SYMBOL(drm_helper_crtc_enable_color_mgmt);