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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/export.h>
33#include <linux/moduleparam.h>
34
35#include <drm/drm_bridge.h>
36#include <drm/drm_client.h>
37#include <drm/drm_crtc.h>
38#include <drm/drm_edid.h>
39#include <drm/drm_fourcc.h>
40#include <drm/drm_modeset_helper_vtables.h>
41#include <drm/drm_print.h>
42#include <drm/drm_probe_helper.h>
43#include <drm/drm_sysfs.h>
44
45#include "drm_crtc_helper_internal.h"
46
47/**
48 * DOC: output probing helper overview
49 *
50 * This library provides some helper code for output probing. It provides an
51 * implementation of the core &drm_connector_funcs.fill_modes interface with
52 * drm_helper_probe_single_connector_modes().
53 *
54 * It also provides support for polling connectors with a work item and for
55 * generic hotplug interrupt handling where the driver doesn't or cannot keep
56 * track of a per-connector hpd interrupt.
57 *
58 * This helper library can be used independently of the modeset helper library.
59 * Drivers can also overwrite different parts e.g. use their own hotplug
60 * handling code to avoid probing unrelated outputs.
61 *
62 * The probe helpers share the function table structures with other display
63 * helper libraries. See &struct drm_connector_helper_funcs for the details.
64 */
65
66static bool drm_kms_helper_poll = true;
67module_param_named(poll, drm_kms_helper_poll, bool, 0600);
68
69static enum drm_mode_status
70drm_mode_validate_flag(const struct drm_display_mode *mode,
71 int flags)
72{
73 if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
74 !(flags & DRM_MODE_FLAG_INTERLACE))
75 return MODE_NO_INTERLACE;
76
77 if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
78 !(flags & DRM_MODE_FLAG_DBLSCAN))
79 return MODE_NO_DBLESCAN;
80
81 if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
82 !(flags & DRM_MODE_FLAG_3D_MASK))
83 return MODE_NO_STEREO;
84
85 return MODE_OK;
86}
87
88static int
89drm_mode_validate_pipeline(struct drm_display_mode *mode,
90 struct drm_connector *connector,
91 struct drm_modeset_acquire_ctx *ctx,
92 enum drm_mode_status *status)
93{
94 struct drm_device *dev = connector->dev;
95 struct drm_encoder *encoder;
96 int ret;
97
98 /* Step 1: Validate against connector */
99 ret = drm_connector_mode_valid(connector, mode, ctx, status);
100 if (ret || *status != MODE_OK)
101 return ret;
102
103 /* Step 2: Validate against encoders and crtcs */
104 drm_connector_for_each_possible_encoder(connector, encoder) {
105 struct drm_bridge *bridge;
106 struct drm_crtc *crtc;
107
108 *status = drm_encoder_mode_valid(encoder, mode);
109 if (*status != MODE_OK) {
110 /* No point in continuing for crtc check as this encoder
111 * will not accept the mode anyway. If all encoders
112 * reject the mode then, at exit, ret will not be
113 * MODE_OK. */
114 continue;
115 }
116
117 bridge = drm_bridge_chain_get_first_bridge(encoder);
118 *status = drm_bridge_chain_mode_valid(bridge,
119 &connector->display_info,
120 mode);
121 if (*status != MODE_OK) {
122 /* There is also no point in continuing for crtc check
123 * here. */
124 continue;
125 }
126
127 drm_for_each_crtc(crtc, dev) {
128 if (!drm_encoder_crtc_ok(encoder, crtc))
129 continue;
130
131 *status = drm_crtc_mode_valid(crtc, mode);
132 if (*status == MODE_OK) {
133 /* If we get to this point there is at least
134 * one combination of encoder+crtc that works
135 * for this mode. Lets return now. */
136 return 0;
137 }
138 }
139 }
140
141 return 0;
142}
143
144static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)
145{
146 struct drm_cmdline_mode *cmdline_mode;
147 struct drm_display_mode *mode;
148
149 cmdline_mode = &connector->cmdline_mode;
150 if (!cmdline_mode->specified)
151 return 0;
152
153 /* Only add a GTF mode if we find no matching probed modes */
154 list_for_each_entry(mode, &connector->probed_modes, head) {
155 if (mode->hdisplay != cmdline_mode->xres ||
156 mode->vdisplay != cmdline_mode->yres)
157 continue;
158
159 if (cmdline_mode->refresh_specified) {
160 /* The probed mode's vrefresh is set until later */
161 if (drm_mode_vrefresh(mode) != cmdline_mode->refresh)
162 continue;
163 }
164
165 /* Mark the matching mode as being preferred by the user */
166 mode->type |= DRM_MODE_TYPE_USERDEF;
167 return 0;
168 }
169
170 mode = drm_mode_create_from_cmdline_mode(connector->dev,
171 cmdline_mode);
172 if (mode == NULL)
173 return 0;
174
175 drm_mode_probed_add(connector, mode);
176 return 1;
177}
178
179enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc,
180 const struct drm_display_mode *mode)
181{
182 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
183
184 if (!crtc_funcs || !crtc_funcs->mode_valid)
185 return MODE_OK;
186
187 return crtc_funcs->mode_valid(crtc, mode);
188}
189
190enum drm_mode_status drm_encoder_mode_valid(struct drm_encoder *encoder,
191 const struct drm_display_mode *mode)
192{
193 const struct drm_encoder_helper_funcs *encoder_funcs =
194 encoder->helper_private;
195
196 if (!encoder_funcs || !encoder_funcs->mode_valid)
197 return MODE_OK;
198
199 return encoder_funcs->mode_valid(encoder, mode);
200}
201
202int
203drm_connector_mode_valid(struct drm_connector *connector,
204 struct drm_display_mode *mode,
205 struct drm_modeset_acquire_ctx *ctx,
206 enum drm_mode_status *status)
207{
208 const struct drm_connector_helper_funcs *connector_funcs =
209 connector->helper_private;
210 int ret = 0;
211
212 if (!connector_funcs)
213 *status = MODE_OK;
214 else if (connector_funcs->mode_valid_ctx)
215 ret = connector_funcs->mode_valid_ctx(connector, mode, ctx,
216 status);
217 else if (connector_funcs->mode_valid)
218 *status = connector_funcs->mode_valid(connector, mode);
219 else
220 *status = MODE_OK;
221
222 return ret;
223}
224
225static void drm_kms_helper_disable_hpd(struct drm_device *dev)
226{
227 struct drm_connector *connector;
228 struct drm_connector_list_iter conn_iter;
229
230 drm_connector_list_iter_begin(dev, &conn_iter);
231 drm_for_each_connector_iter(connector, &conn_iter) {
232 const struct drm_connector_helper_funcs *funcs =
233 connector->helper_private;
234
235 if (funcs && funcs->disable_hpd)
236 funcs->disable_hpd(connector);
237 }
238 drm_connector_list_iter_end(&conn_iter);
239}
240
241static bool drm_kms_helper_enable_hpd(struct drm_device *dev)
242{
243 bool poll = false;
244 struct drm_connector *connector;
245 struct drm_connector_list_iter conn_iter;
246
247 drm_connector_list_iter_begin(dev, &conn_iter);
248 drm_for_each_connector_iter(connector, &conn_iter) {
249 const struct drm_connector_helper_funcs *funcs =
250 connector->helper_private;
251
252 if (funcs && funcs->enable_hpd)
253 funcs->enable_hpd(connector);
254
255 if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
256 DRM_CONNECTOR_POLL_DISCONNECT))
257 poll = true;
258 }
259 drm_connector_list_iter_end(&conn_iter);
260
261 return poll;
262}
263
264#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
265static void reschedule_output_poll_work(struct drm_device *dev)
266{
267 unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
268
269 if (dev->mode_config.delayed_event)
270 /*
271 * FIXME:
272 *
273 * Use short (1s) delay to handle the initial delayed event.
274 * This delay should not be needed, but Optimus/nouveau will
275 * fail in a mysterious way if the delayed event is handled as
276 * soon as possible like it is done in
277 * drm_helper_probe_single_connector_modes() in case the poll
278 * was enabled before.
279 */
280 delay = HZ;
281
282 schedule_delayed_work(&dev->mode_config.output_poll_work, delay);
283}
284
285/**
286 * drm_kms_helper_poll_enable - re-enable output polling.
287 * @dev: drm_device
288 *
289 * This function re-enables the output polling work, after it has been
290 * temporarily disabled using drm_kms_helper_poll_disable(), for example over
291 * suspend/resume.
292 *
293 * Drivers can call this helper from their device resume implementation. It is
294 * not an error to call this even when output polling isn't enabled.
295 *
296 * If device polling was never initialized before, this call will trigger a
297 * warning and return.
298 *
299 * Note that calls to enable and disable polling must be strictly ordered, which
300 * is automatically the case when they're only call from suspend/resume
301 * callbacks.
302 */
303void drm_kms_helper_poll_enable(struct drm_device *dev)
304{
305 if (drm_WARN_ON_ONCE(dev, !dev->mode_config.poll_enabled) ||
306 !drm_kms_helper_poll || dev->mode_config.poll_running)
307 return;
308
309 if (drm_kms_helper_enable_hpd(dev) ||
310 dev->mode_config.delayed_event)
311 reschedule_output_poll_work(dev);
312
313 dev->mode_config.poll_running = true;
314}
315EXPORT_SYMBOL(drm_kms_helper_poll_enable);
316
317/**
318 * drm_kms_helper_poll_reschedule - reschedule the output polling work
319 * @dev: drm_device
320 *
321 * This function reschedules the output polling work, after polling for a
322 * connector has been enabled.
323 *
324 * Drivers must call this helper after enabling polling for a connector by
325 * setting %DRM_CONNECTOR_POLL_CONNECT / %DRM_CONNECTOR_POLL_DISCONNECT flags
326 * in drm_connector::polled. Note that after disabling polling by clearing these
327 * flags for a connector will stop the output polling work automatically if
328 * the polling is disabled for all other connectors as well.
329 *
330 * The function can be called only after polling has been enabled by calling
331 * drm_kms_helper_poll_init() / drm_kms_helper_poll_enable().
332 */
333void drm_kms_helper_poll_reschedule(struct drm_device *dev)
334{
335 if (dev->mode_config.poll_running)
336 reschedule_output_poll_work(dev);
337}
338EXPORT_SYMBOL(drm_kms_helper_poll_reschedule);
339
340static enum drm_connector_status
341drm_helper_probe_detect_ctx(struct drm_connector *connector, bool force)
342{
343 const struct drm_connector_helper_funcs *funcs = connector->helper_private;
344 struct drm_modeset_acquire_ctx ctx;
345 int ret;
346
347 drm_modeset_acquire_init(&ctx, 0);
348
349retry:
350 ret = drm_modeset_lock(&connector->dev->mode_config.connection_mutex, &ctx);
351 if (!ret) {
352 if (funcs->detect_ctx)
353 ret = funcs->detect_ctx(connector, &ctx, force);
354 else if (connector->funcs->detect)
355 ret = connector->funcs->detect(connector, force);
356 else
357 ret = connector_status_connected;
358 }
359
360 if (ret == -EDEADLK) {
361 drm_modeset_backoff(&ctx);
362 goto retry;
363 }
364
365 if (WARN_ON(ret < 0))
366 ret = connector_status_unknown;
367
368 if (ret != connector->status)
369 connector->epoch_counter += 1;
370
371 drm_modeset_drop_locks(&ctx);
372 drm_modeset_acquire_fini(&ctx);
373
374 return ret;
375}
376
377/**
378 * drm_helper_probe_detect - probe connector status
379 * @connector: connector to probe
380 * @ctx: acquire_ctx, or NULL to let this function handle locking.
381 * @force: Whether destructive probe operations should be performed.
382 *
383 * This function calls the detect callbacks of the connector.
384 * This function returns &drm_connector_status, or
385 * if @ctx is set, it might also return -EDEADLK.
386 */
387int
388drm_helper_probe_detect(struct drm_connector *connector,
389 struct drm_modeset_acquire_ctx *ctx,
390 bool force)
391{
392 const struct drm_connector_helper_funcs *funcs = connector->helper_private;
393 struct drm_device *dev = connector->dev;
394 int ret;
395
396 if (!ctx)
397 return drm_helper_probe_detect_ctx(connector, force);
398
399 ret = drm_modeset_lock(&dev->mode_config.connection_mutex, ctx);
400 if (ret)
401 return ret;
402
403 if (funcs->detect_ctx)
404 ret = funcs->detect_ctx(connector, ctx, force);
405 else if (connector->funcs->detect)
406 ret = connector->funcs->detect(connector, force);
407 else
408 ret = connector_status_connected;
409
410 if (ret != connector->status)
411 connector->epoch_counter += 1;
412
413 return ret;
414}
415EXPORT_SYMBOL(drm_helper_probe_detect);
416
417static int drm_helper_probe_get_modes(struct drm_connector *connector)
418{
419 const struct drm_connector_helper_funcs *connector_funcs =
420 connector->helper_private;
421 int count;
422
423 count = connector_funcs->get_modes(connector);
424
425 /* The .get_modes() callback should not return negative values. */
426 if (count < 0) {
427 drm_err(connector->dev, ".get_modes() returned %pe\n",
428 ERR_PTR(count));
429 count = 0;
430 }
431
432 /*
433 * Fallback for when DDC probe failed in drm_get_edid() and thus skipped
434 * override/firmware EDID.
435 */
436 if (count == 0 && connector->status == connector_status_connected)
437 count = drm_edid_override_connector_update(connector);
438
439 return count;
440}
441
442static int __drm_helper_update_and_validate(struct drm_connector *connector,
443 uint32_t maxX, uint32_t maxY,
444 struct drm_modeset_acquire_ctx *ctx)
445{
446 struct drm_device *dev = connector->dev;
447 struct drm_display_mode *mode;
448 int mode_flags = 0;
449 int ret;
450
451 drm_connector_list_update(connector);
452
453 if (connector->interlace_allowed)
454 mode_flags |= DRM_MODE_FLAG_INTERLACE;
455 if (connector->doublescan_allowed)
456 mode_flags |= DRM_MODE_FLAG_DBLSCAN;
457 if (connector->stereo_allowed)
458 mode_flags |= DRM_MODE_FLAG_3D_MASK;
459
460 list_for_each_entry(mode, &connector->modes, head) {
461 if (mode->status != MODE_OK)
462 continue;
463
464 mode->status = drm_mode_validate_driver(dev, mode);
465 if (mode->status != MODE_OK)
466 continue;
467
468 mode->status = drm_mode_validate_size(mode, maxX, maxY);
469 if (mode->status != MODE_OK)
470 continue;
471
472 mode->status = drm_mode_validate_flag(mode, mode_flags);
473 if (mode->status != MODE_OK)
474 continue;
475
476 ret = drm_mode_validate_pipeline(mode, connector, ctx,
477 &mode->status);
478 if (ret) {
479 drm_dbg_kms(dev,
480 "drm_mode_validate_pipeline failed: %d\n",
481 ret);
482
483 if (drm_WARN_ON_ONCE(dev, ret != -EDEADLK))
484 mode->status = MODE_ERROR;
485 else
486 return -EDEADLK;
487 }
488
489 if (mode->status != MODE_OK)
490 continue;
491 mode->status = drm_mode_validate_ycbcr420(mode, connector);
492 }
493
494 return 0;
495}
496
497/**
498 * drm_helper_probe_single_connector_modes - get complete set of display modes
499 * @connector: connector to probe
500 * @maxX: max width for modes
501 * @maxY: max height for modes
502 *
503 * Based on the helper callbacks implemented by @connector in struct
504 * &drm_connector_helper_funcs try to detect all valid modes. Modes will first
505 * be added to the connector's probed_modes list, then culled (based on validity
506 * and the @maxX, @maxY parameters) and put into the normal modes list.
507 *
508 * Intended to be used as a generic implementation of the
509 * &drm_connector_funcs.fill_modes() vfunc for drivers that use the CRTC helpers
510 * for output mode filtering and detection.
511 *
512 * The basic procedure is as follows
513 *
514 * 1. All modes currently on the connector's modes list are marked as stale
515 *
516 * 2. New modes are added to the connector's probed_modes list with
517 * drm_mode_probed_add(). New modes start their life with status as OK.
518 * Modes are added from a single source using the following priority order.
519 *
520 * - &drm_connector_helper_funcs.get_modes vfunc
521 * - if the connector status is connector_status_connected, standard
522 * VESA DMT modes up to 1024x768 are automatically added
523 * (drm_add_modes_noedid())
524 *
525 * Finally modes specified via the kernel command line (video=...) are
526 * added in addition to what the earlier probes produced
527 * (drm_helper_probe_add_cmdline_mode()). These modes are generated
528 * using the VESA GTF/CVT formulas.
529 *
530 * 3. Modes are moved from the probed_modes list to the modes list. Potential
531 * duplicates are merged together (see drm_connector_list_update()).
532 * After this step the probed_modes list will be empty again.
533 *
534 * 4. Any non-stale mode on the modes list then undergoes validation
535 *
536 * - drm_mode_validate_basic() performs basic sanity checks
537 * - drm_mode_validate_size() filters out modes larger than @maxX and @maxY
538 * (if specified)
539 * - drm_mode_validate_flag() checks the modes against basic connector
540 * capabilities (interlace_allowed,doublescan_allowed,stereo_allowed)
541 * - the optional &drm_connector_helper_funcs.mode_valid or
542 * &drm_connector_helper_funcs.mode_valid_ctx helpers can perform driver
543 * and/or sink specific checks
544 * - the optional &drm_crtc_helper_funcs.mode_valid,
545 * &drm_bridge_funcs.mode_valid and &drm_encoder_helper_funcs.mode_valid
546 * helpers can perform driver and/or source specific checks which are also
547 * enforced by the modeset/atomic helpers
548 *
549 * 5. Any mode whose status is not OK is pruned from the connector's modes list,
550 * accompanied by a debug message indicating the reason for the mode's
551 * rejection (see drm_mode_prune_invalid()).
552 *
553 * Returns:
554 * The number of modes found on @connector.
555 */
556int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
557 uint32_t maxX, uint32_t maxY)
558{
559 struct drm_device *dev = connector->dev;
560 struct drm_display_mode *mode;
561 int count = 0, ret;
562 enum drm_connector_status old_status;
563 struct drm_modeset_acquire_ctx ctx;
564
565 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
566
567 drm_modeset_acquire_init(&ctx, 0);
568
569 DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
570 connector->name);
571
572retry:
573 ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
574 if (ret == -EDEADLK) {
575 drm_modeset_backoff(&ctx);
576 goto retry;
577 } else
578 WARN_ON(ret < 0);
579
580 /* set all old modes to the stale state */
581 list_for_each_entry(mode, &connector->modes, head)
582 mode->status = MODE_STALE;
583
584 old_status = connector->status;
585
586 if (connector->force) {
587 if (connector->force == DRM_FORCE_ON ||
588 connector->force == DRM_FORCE_ON_DIGITAL)
589 connector->status = connector_status_connected;
590 else
591 connector->status = connector_status_disconnected;
592 if (connector->funcs->force)
593 connector->funcs->force(connector);
594 } else {
595 ret = drm_helper_probe_detect(connector, &ctx, true);
596
597 if (ret == -EDEADLK) {
598 drm_modeset_backoff(&ctx);
599 goto retry;
600 } else if (WARN(ret < 0, "Invalid return value %i for connector detection\n", ret))
601 ret = connector_status_unknown;
602
603 connector->status = ret;
604 }
605
606 /*
607 * Normally either the driver's hpd code or the poll loop should
608 * pick up any changes and fire the hotplug event. But if
609 * userspace sneaks in a probe, we might miss a change. Hence
610 * check here, and if anything changed start the hotplug code.
611 */
612 if (old_status != connector->status) {
613 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
614 connector->base.id,
615 connector->name,
616 drm_get_connector_status_name(old_status),
617 drm_get_connector_status_name(connector->status));
618
619 /*
620 * The hotplug event code might call into the fb
621 * helpers, and so expects that we do not hold any
622 * locks. Fire up the poll struct instead, it will
623 * disable itself again.
624 */
625 dev->mode_config.delayed_event = true;
626 if (dev->mode_config.poll_enabled)
627 mod_delayed_work(system_wq,
628 &dev->mode_config.output_poll_work,
629 0);
630 }
631
632 /*
633 * Re-enable polling in case the global poll config changed but polling
634 * is still initialized.
635 */
636 if (dev->mode_config.poll_enabled)
637 drm_kms_helper_poll_enable(dev);
638
639 if (connector->status == connector_status_disconnected) {
640 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",
641 connector->base.id, connector->name);
642 drm_connector_update_edid_property(connector, NULL);
643 drm_mode_prune_invalid(dev, &connector->modes, false);
644 goto exit;
645 }
646
647 count = drm_helper_probe_get_modes(connector);
648
649 if (count == 0 && (connector->status == connector_status_connected ||
650 connector->status == connector_status_unknown)) {
651 count = drm_add_modes_noedid(connector, 1024, 768);
652
653 /*
654 * Section 4.2.2.6 (EDID Corruption Detection) of the DP 1.4a
655 * Link CTS specifies that 640x480 (the official "failsafe"
656 * mode) needs to be the default if there's no EDID.
657 */
658 if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort)
659 drm_set_preferred_mode(connector, 640, 480);
660 }
661 count += drm_helper_probe_add_cmdline_mode(connector);
662 if (count != 0) {
663 ret = __drm_helper_update_and_validate(connector, maxX, maxY, &ctx);
664 if (ret == -EDEADLK) {
665 drm_modeset_backoff(&ctx);
666 goto retry;
667 }
668 }
669
670 drm_mode_prune_invalid(dev, &connector->modes, true);
671
672 /*
673 * Displayport spec section 5.2.1.2 ("Video Timing Format") says that
674 * all detachable sinks shall support 640x480 @60Hz as a fail safe
675 * mode. If all modes were pruned, perhaps because they need more
676 * lanes or a higher pixel clock than available, at least try to add
677 * in 640x480.
678 */
679 if (list_empty(&connector->modes) &&
680 connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort) {
681 count = drm_add_modes_noedid(connector, 640, 480);
682 ret = __drm_helper_update_and_validate(connector, maxX, maxY, &ctx);
683 if (ret == -EDEADLK) {
684 drm_modeset_backoff(&ctx);
685 goto retry;
686 }
687 drm_mode_prune_invalid(dev, &connector->modes, true);
688 }
689
690exit:
691 drm_modeset_drop_locks(&ctx);
692 drm_modeset_acquire_fini(&ctx);
693
694 if (list_empty(&connector->modes))
695 return 0;
696
697 drm_mode_sort(&connector->modes);
698
699 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id,
700 connector->name);
701 list_for_each_entry(mode, &connector->modes, head) {
702 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
703 drm_mode_debug_printmodeline(mode);
704 }
705
706 return count;
707}
708EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
709
710/**
711 * drm_kms_helper_hotplug_event - fire off KMS hotplug events
712 * @dev: drm_device whose connector state changed
713 *
714 * This function fires off the uevent for userspace and also calls the
715 * output_poll_changed function, which is most commonly used to inform the fbdev
716 * emulation code and allow it to update the fbcon output configuration.
717 *
718 * Drivers should call this from their hotplug handling code when a change is
719 * detected. Note that this function does not do any output detection of its
720 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
721 * driver already.
722 *
723 * This function must be called from process context with no mode
724 * setting locks held.
725 *
726 * If only a single connector has changed, consider calling
727 * drm_kms_helper_connector_hotplug_event() instead.
728 */
729void drm_kms_helper_hotplug_event(struct drm_device *dev)
730{
731 /* send a uevent + call fbdev */
732 drm_sysfs_hotplug_event(dev);
733 if (dev->mode_config.funcs->output_poll_changed)
734 dev->mode_config.funcs->output_poll_changed(dev);
735
736 drm_client_dev_hotplug(dev);
737}
738EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
739
740/**
741 * drm_kms_helper_connector_hotplug_event - fire off a KMS connector hotplug event
742 * @connector: drm_connector which has changed
743 *
744 * This is the same as drm_kms_helper_hotplug_event(), except it fires a more
745 * fine-grained uevent for a single connector.
746 */
747void drm_kms_helper_connector_hotplug_event(struct drm_connector *connector)
748{
749 struct drm_device *dev = connector->dev;
750
751 /* send a uevent + call fbdev */
752 drm_sysfs_connector_hotplug_event(connector);
753 if (dev->mode_config.funcs->output_poll_changed)
754 dev->mode_config.funcs->output_poll_changed(dev);
755
756 drm_client_dev_hotplug(dev);
757}
758EXPORT_SYMBOL(drm_kms_helper_connector_hotplug_event);
759
760static void output_poll_execute(struct work_struct *work)
761{
762 struct delayed_work *delayed_work = to_delayed_work(work);
763 struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
764 struct drm_connector *connector;
765 struct drm_connector_list_iter conn_iter;
766 enum drm_connector_status old_status;
767 bool repoll = false, changed;
768 u64 old_epoch_counter;
769
770 if (!dev->mode_config.poll_enabled)
771 return;
772
773 /* Pick up any changes detected by the probe functions. */
774 changed = dev->mode_config.delayed_event;
775 dev->mode_config.delayed_event = false;
776
777 if (!drm_kms_helper_poll) {
778 if (dev->mode_config.poll_running) {
779 drm_kms_helper_disable_hpd(dev);
780 dev->mode_config.poll_running = false;
781 }
782 goto out;
783 }
784
785 if (!mutex_trylock(&dev->mode_config.mutex)) {
786 repoll = true;
787 goto out;
788 }
789
790 drm_connector_list_iter_begin(dev, &conn_iter);
791 drm_for_each_connector_iter(connector, &conn_iter) {
792 /* Ignore forced connectors. */
793 if (connector->force)
794 continue;
795
796 /* Ignore HPD capable connectors and connectors where we don't
797 * want any hotplug detection at all for polling. */
798 if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD)
799 continue;
800
801 old_status = connector->status;
802 /* if we are connected and don't want to poll for disconnect
803 skip it */
804 if (old_status == connector_status_connected &&
805 !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
806 continue;
807
808 repoll = true;
809
810 old_epoch_counter = connector->epoch_counter;
811 connector->status = drm_helper_probe_detect(connector, NULL, false);
812 if (old_epoch_counter != connector->epoch_counter) {
813 const char *old, *new;
814
815 /*
816 * The poll work sets force=false when calling detect so
817 * that drivers can avoid to do disruptive tests (e.g.
818 * when load detect cycles could cause flickering on
819 * other, running displays). This bears the risk that we
820 * flip-flop between unknown here in the poll work and
821 * the real state when userspace forces a full detect
822 * call after receiving a hotplug event due to this
823 * change.
824 *
825 * Hence clamp an unknown detect status to the old
826 * value.
827 */
828 if (connector->status == connector_status_unknown) {
829 connector->status = old_status;
830 continue;
831 }
832
833 old = drm_get_connector_status_name(old_status);
834 new = drm_get_connector_status_name(connector->status);
835
836 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] "
837 "status updated from %s to %s\n",
838 connector->base.id,
839 connector->name,
840 old, new);
841 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] epoch counter %llu -> %llu\n",
842 connector->base.id, connector->name,
843 old_epoch_counter, connector->epoch_counter);
844
845 changed = true;
846 }
847 }
848 drm_connector_list_iter_end(&conn_iter);
849
850 mutex_unlock(&dev->mode_config.mutex);
851
852out:
853 if (changed)
854 drm_kms_helper_hotplug_event(dev);
855
856 if (repoll)
857 schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
858}
859
860/**
861 * drm_kms_helper_is_poll_worker - is %current task an output poll worker?
862 *
863 * Determine if %current task is an output poll worker. This can be used
864 * to select distinct code paths for output polling versus other contexts.
865 *
866 * One use case is to avoid a deadlock between the output poll worker and
867 * the autosuspend worker wherein the latter waits for polling to finish
868 * upon calling drm_kms_helper_poll_disable(), while the former waits for
869 * runtime suspend to finish upon calling pm_runtime_get_sync() in a
870 * connector ->detect hook.
871 */
872bool drm_kms_helper_is_poll_worker(void)
873{
874 struct work_struct *work = current_work();
875
876 return work && work->func == output_poll_execute;
877}
878EXPORT_SYMBOL(drm_kms_helper_is_poll_worker);
879
880/**
881 * drm_kms_helper_poll_disable - disable output polling
882 * @dev: drm_device
883 *
884 * This function disables the output polling work.
885 *
886 * Drivers can call this helper from their device suspend implementation. It is
887 * not an error to call this even when output polling isn't enabled or already
888 * disabled. Polling is re-enabled by calling drm_kms_helper_poll_enable().
889 *
890 * If however, the polling was never initialized, this call will trigger a
891 * warning and return
892 *
893 * Note that calls to enable and disable polling must be strictly ordered, which
894 * is automatically the case when they're only call from suspend/resume
895 * callbacks.
896 */
897void drm_kms_helper_poll_disable(struct drm_device *dev)
898{
899 if (drm_WARN_ON(dev, !dev->mode_config.poll_enabled))
900 return;
901
902 if (dev->mode_config.poll_running)
903 drm_kms_helper_disable_hpd(dev);
904
905 cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
906
907 dev->mode_config.poll_running = false;
908}
909EXPORT_SYMBOL(drm_kms_helper_poll_disable);
910
911/**
912 * drm_kms_helper_poll_init - initialize and enable output polling
913 * @dev: drm_device
914 *
915 * This function initializes and then also enables output polling support for
916 * @dev. Drivers which do not have reliable hotplug support in hardware can use
917 * this helper infrastructure to regularly poll such connectors for changes in
918 * their connection state.
919 *
920 * Drivers can control which connectors are polled by setting the
921 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
922 * connectors where probing live outputs can result in visual distortion drivers
923 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
924 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
925 * completely ignored by the polling logic.
926 *
927 * Note that a connector can be both polled and probed from the hotplug handler,
928 * in case the hotplug interrupt is known to be unreliable.
929 */
930void drm_kms_helper_poll_init(struct drm_device *dev)
931{
932 INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
933 dev->mode_config.poll_enabled = true;
934
935 drm_kms_helper_poll_enable(dev);
936}
937EXPORT_SYMBOL(drm_kms_helper_poll_init);
938
939/**
940 * drm_kms_helper_poll_fini - disable output polling and clean it up
941 * @dev: drm_device
942 */
943void drm_kms_helper_poll_fini(struct drm_device *dev)
944{
945 if (!dev->mode_config.poll_enabled)
946 return;
947
948 drm_kms_helper_poll_disable(dev);
949
950 dev->mode_config.poll_enabled = false;
951}
952EXPORT_SYMBOL(drm_kms_helper_poll_fini);
953
954static bool check_connector_changed(struct drm_connector *connector)
955{
956 struct drm_device *dev = connector->dev;
957 enum drm_connector_status old_status;
958 u64 old_epoch_counter;
959
960 /* Only handle HPD capable connectors. */
961 drm_WARN_ON(dev, !(connector->polled & DRM_CONNECTOR_POLL_HPD));
962
963 drm_WARN_ON(dev, !mutex_is_locked(&dev->mode_config.mutex));
964
965 old_status = connector->status;
966 old_epoch_counter = connector->epoch_counter;
967 connector->status = drm_helper_probe_detect(connector, NULL, false);
968
969 if (old_epoch_counter == connector->epoch_counter) {
970 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Same epoch counter %llu\n",
971 connector->base.id,
972 connector->name,
973 connector->epoch_counter);
974
975 return false;
976 }
977
978 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n",
979 connector->base.id,
980 connector->name,
981 drm_get_connector_status_name(old_status),
982 drm_get_connector_status_name(connector->status));
983
984 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Changed epoch counter %llu => %llu\n",
985 connector->base.id,
986 connector->name,
987 old_epoch_counter,
988 connector->epoch_counter);
989
990 return true;
991}
992
993/**
994 * drm_connector_helper_hpd_irq_event - hotplug processing
995 * @connector: drm_connector
996 *
997 * Drivers can use this helper function to run a detect cycle on a connector
998 * which has the DRM_CONNECTOR_POLL_HPD flag set in its &polled member.
999 *
1000 * This helper function is useful for drivers which can track hotplug
1001 * interrupts for a single connector. Drivers that want to send a
1002 * hotplug event for all connectors or can't track hotplug interrupts
1003 * per connector need to use drm_helper_hpd_irq_event().
1004 *
1005 * This function must be called from process context with no mode
1006 * setting locks held.
1007 *
1008 * Note that a connector can be both polled and probed from the hotplug
1009 * handler, in case the hotplug interrupt is known to be unreliable.
1010 *
1011 * Returns:
1012 * A boolean indicating whether the connector status changed or not
1013 */
1014bool drm_connector_helper_hpd_irq_event(struct drm_connector *connector)
1015{
1016 struct drm_device *dev = connector->dev;
1017 bool changed;
1018
1019 mutex_lock(&dev->mode_config.mutex);
1020 changed = check_connector_changed(connector);
1021 mutex_unlock(&dev->mode_config.mutex);
1022
1023 if (changed) {
1024 drm_kms_helper_connector_hotplug_event(connector);
1025 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Sent hotplug event\n",
1026 connector->base.id,
1027 connector->name);
1028 }
1029
1030 return changed;
1031}
1032EXPORT_SYMBOL(drm_connector_helper_hpd_irq_event);
1033
1034/**
1035 * drm_helper_hpd_irq_event - hotplug processing
1036 * @dev: drm_device
1037 *
1038 * Drivers can use this helper function to run a detect cycle on all connectors
1039 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
1040 * other connectors are ignored, which is useful to avoid reprobing fixed
1041 * panels.
1042 *
1043 * This helper function is useful for drivers which can't or don't track hotplug
1044 * interrupts for each connector.
1045 *
1046 * Drivers which support hotplug interrupts for each connector individually and
1047 * which have a more fine-grained detect logic can use
1048 * drm_connector_helper_hpd_irq_event(). Alternatively, they should bypass this
1049 * code and directly call drm_kms_helper_hotplug_event() in case the connector
1050 * state changed.
1051 *
1052 * This function must be called from process context with no mode
1053 * setting locks held.
1054 *
1055 * Note that a connector can be both polled and probed from the hotplug handler,
1056 * in case the hotplug interrupt is known to be unreliable.
1057 *
1058 * Returns:
1059 * A boolean indicating whether the connector status changed or not
1060 */
1061bool drm_helper_hpd_irq_event(struct drm_device *dev)
1062{
1063 struct drm_connector *connector, *first_changed_connector = NULL;
1064 struct drm_connector_list_iter conn_iter;
1065 int changed = 0;
1066
1067 if (!dev->mode_config.poll_enabled)
1068 return false;
1069
1070 mutex_lock(&dev->mode_config.mutex);
1071 drm_connector_list_iter_begin(dev, &conn_iter);
1072 drm_for_each_connector_iter(connector, &conn_iter) {
1073 /* Only handle HPD capable connectors. */
1074 if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
1075 continue;
1076
1077 if (check_connector_changed(connector)) {
1078 if (!first_changed_connector) {
1079 drm_connector_get(connector);
1080 first_changed_connector = connector;
1081 }
1082
1083 changed++;
1084 }
1085 }
1086 drm_connector_list_iter_end(&conn_iter);
1087 mutex_unlock(&dev->mode_config.mutex);
1088
1089 if (changed == 1)
1090 drm_kms_helper_connector_hotplug_event(first_changed_connector);
1091 else if (changed > 0)
1092 drm_kms_helper_hotplug_event(dev);
1093
1094 if (first_changed_connector)
1095 drm_connector_put(first_changed_connector);
1096
1097 return changed;
1098}
1099EXPORT_SYMBOL(drm_helper_hpd_irq_event);
1100
1101/**
1102 * drm_crtc_helper_mode_valid_fixed - Validates a display mode
1103 * @crtc: the crtc
1104 * @mode: the mode to validate
1105 * @fixed_mode: the display hardware's mode
1106 *
1107 * Returns:
1108 * MODE_OK on success, or another mode-status code otherwise.
1109 */
1110enum drm_mode_status drm_crtc_helper_mode_valid_fixed(struct drm_crtc *crtc,
1111 const struct drm_display_mode *mode,
1112 const struct drm_display_mode *fixed_mode)
1113{
1114 if (mode->hdisplay != fixed_mode->hdisplay && mode->vdisplay != fixed_mode->vdisplay)
1115 return MODE_ONE_SIZE;
1116 else if (mode->hdisplay != fixed_mode->hdisplay)
1117 return MODE_ONE_WIDTH;
1118 else if (mode->vdisplay != fixed_mode->vdisplay)
1119 return MODE_ONE_HEIGHT;
1120
1121 return MODE_OK;
1122}
1123EXPORT_SYMBOL(drm_crtc_helper_mode_valid_fixed);
1124
1125/**
1126 * drm_connector_helper_get_modes_fixed - Duplicates a display mode for a connector
1127 * @connector: the connector
1128 * @fixed_mode: the display hardware's mode
1129 *
1130 * This function duplicates a display modes for a connector. Drivers for hardware
1131 * that only supports a single fixed mode can use this function in their connector's
1132 * get_modes helper.
1133 *
1134 * Returns:
1135 * The number of created modes.
1136 */
1137int drm_connector_helper_get_modes_fixed(struct drm_connector *connector,
1138 const struct drm_display_mode *fixed_mode)
1139{
1140 struct drm_device *dev = connector->dev;
1141 struct drm_display_mode *mode;
1142
1143 mode = drm_mode_duplicate(dev, fixed_mode);
1144 if (!mode) {
1145 drm_err(dev, "Failed to duplicate mode " DRM_MODE_FMT "\n",
1146 DRM_MODE_ARG(fixed_mode));
1147 return 0;
1148 }
1149
1150 if (mode->name[0] == '\0')
1151 drm_mode_set_name(mode);
1152
1153 mode->type |= DRM_MODE_TYPE_PREFERRED;
1154 drm_mode_probed_add(connector, mode);
1155
1156 if (mode->width_mm)
1157 connector->display_info.width_mm = mode->width_mm;
1158 if (mode->height_mm)
1159 connector->display_info.height_mm = mode->height_mm;
1160
1161 return 1;
1162}
1163EXPORT_SYMBOL(drm_connector_helper_get_modes_fixed);
1164
1165/**
1166 * drm_connector_helper_get_modes - Read EDID and update connector.
1167 * @connector: The connector
1168 *
1169 * Read the EDID using drm_edid_read() (which requires that connector->ddc is
1170 * set), and update the connector using the EDID.
1171 *
1172 * This can be used as the "default" connector helper .get_modes() hook if the
1173 * driver does not need any special processing. This is sets the example what
1174 * custom .get_modes() hooks should do regarding EDID read and connector update.
1175 *
1176 * Returns: Number of modes.
1177 */
1178int drm_connector_helper_get_modes(struct drm_connector *connector)
1179{
1180 const struct drm_edid *drm_edid;
1181 int count;
1182
1183 drm_edid = drm_edid_read(connector);
1184
1185 /*
1186 * Unconditionally update the connector. If the EDID was read
1187 * successfully, fill in the connector information derived from the
1188 * EDID. Otherwise, if the EDID is NULL, clear the connector
1189 * information.
1190 */
1191 drm_edid_connector_update(connector, drm_edid);
1192
1193 count = drm_edid_connector_add_modes(connector);
1194
1195 drm_edid_free(drm_edid);
1196
1197 return count;
1198}
1199EXPORT_SYMBOL(drm_connector_helper_get_modes);
1200
1201/**
1202 * drm_connector_helper_tv_get_modes - Fills the modes availables to a TV connector
1203 * @connector: The connector
1204 *
1205 * Fills the available modes for a TV connector based on the supported
1206 * TV modes, and the default mode expressed by the kernel command line.
1207 *
1208 * This can be used as the default TV connector helper .get_modes() hook
1209 * if the driver does not need any special processing.
1210 *
1211 * Returns:
1212 * The number of modes added to the connector.
1213 */
1214int drm_connector_helper_tv_get_modes(struct drm_connector *connector)
1215{
1216 struct drm_device *dev = connector->dev;
1217 struct drm_property *tv_mode_property =
1218 dev->mode_config.tv_mode_property;
1219 struct drm_cmdline_mode *cmdline = &connector->cmdline_mode;
1220 unsigned int ntsc_modes = BIT(DRM_MODE_TV_MODE_NTSC) |
1221 BIT(DRM_MODE_TV_MODE_NTSC_443) |
1222 BIT(DRM_MODE_TV_MODE_NTSC_J) |
1223 BIT(DRM_MODE_TV_MODE_PAL_M);
1224 unsigned int pal_modes = BIT(DRM_MODE_TV_MODE_PAL) |
1225 BIT(DRM_MODE_TV_MODE_PAL_N) |
1226 BIT(DRM_MODE_TV_MODE_SECAM);
1227 unsigned int tv_modes[2] = { UINT_MAX, UINT_MAX };
1228 unsigned int i, supported_tv_modes = 0;
1229
1230 if (!tv_mode_property)
1231 return 0;
1232
1233 for (i = 0; i < tv_mode_property->num_values; i++)
1234 supported_tv_modes |= BIT(tv_mode_property->values[i]);
1235
1236 if ((supported_tv_modes & ntsc_modes) &&
1237 (supported_tv_modes & pal_modes)) {
1238 uint64_t default_mode;
1239
1240 if (drm_object_property_get_default_value(&connector->base,
1241 tv_mode_property,
1242 &default_mode))
1243 return 0;
1244
1245 if (cmdline->tv_mode_specified)
1246 default_mode = cmdline->tv_mode;
1247
1248 if (BIT(default_mode) & ntsc_modes) {
1249 tv_modes[0] = DRM_MODE_TV_MODE_NTSC;
1250 tv_modes[1] = DRM_MODE_TV_MODE_PAL;
1251 } else {
1252 tv_modes[0] = DRM_MODE_TV_MODE_PAL;
1253 tv_modes[1] = DRM_MODE_TV_MODE_NTSC;
1254 }
1255 } else if (supported_tv_modes & ntsc_modes) {
1256 tv_modes[0] = DRM_MODE_TV_MODE_NTSC;
1257 } else if (supported_tv_modes & pal_modes) {
1258 tv_modes[0] = DRM_MODE_TV_MODE_PAL;
1259 } else {
1260 return 0;
1261 }
1262
1263 for (i = 0; i < ARRAY_SIZE(tv_modes); i++) {
1264 struct drm_display_mode *mode;
1265
1266 if (tv_modes[i] == DRM_MODE_TV_MODE_NTSC)
1267 mode = drm_mode_analog_ntsc_480i(dev);
1268 else if (tv_modes[i] == DRM_MODE_TV_MODE_PAL)
1269 mode = drm_mode_analog_pal_576i(dev);
1270 else
1271 break;
1272 if (!mode)
1273 return i;
1274 if (!i)
1275 mode->type |= DRM_MODE_TYPE_PREFERRED;
1276 drm_mode_probed_add(connector, mode);
1277 }
1278
1279 return i;
1280}
1281EXPORT_SYMBOL(drm_connector_helper_tv_get_modes);