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