xref: /dragonfly/sys/dev/drm/drm_crtc_helper.c (revision 3f2dd94a569761201b5b0a18b2f697f97fe1b9dc)
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  */
drm_helper_encoder_in_use(struct drm_encoder * encoder)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  */
drm_helper_crtc_in_use(struct drm_crtc * crtc)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
drm_encoder_disable(struct drm_encoder * encoder)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 
__drm_helper_disable_unused_functions(struct drm_device * dev)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  */
drm_helper_disable_unused_functions(struct drm_device * dev)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
drm_crtc_prepare_encoders(struct drm_device * dev)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  */
drm_crtc_helper_set_mode(struct drm_crtc * crtc,struct drm_display_mode * mode,int x,int y,struct drm_framebuffer * old_fb)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
drm_crtc_helper_disable(struct drm_crtc * crtc)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  */
drm_crtc_helper_set_config(struct drm_mode_set * set,struct drm_modeset_acquire_ctx * ctx)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 
drm_helper_choose_encoder_dpms(struct drm_encoder * encoder)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 */
drm_helper_encoder_dpms(struct drm_encoder * encoder,int mode)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 
drm_helper_choose_crtc_dpms(struct drm_crtc * crtc)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  */
drm_helper_connector_dpms(struct drm_connector * connector,int mode)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  */
drm_helper_resume_force_mode(struct drm_device * dev)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  */
drm_helper_crtc_mode_set(struct drm_crtc * crtc,struct drm_display_mode * mode,struct drm_display_mode * adjusted_mode,int x,int y,struct drm_framebuffer * old_fb)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  */
drm_helper_crtc_mode_set_base(struct drm_crtc * crtc,int x,int y,struct drm_framebuffer * old_fb)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);
1101