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1/*2 * Copyright (c) 2006-2008 Intel Corporation3 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>4 *5 * DRM core CRTC related functions6 *7 * Permission to use, copy, modify, distribute, and sell this software and its8 * documentation for any purpose is hereby granted without fee, provided that9 * the above copyright notice appear in all copies and that both that copyright10 * notice and this permission notice appear in supporting documentation, and11 * that the name of the copyright holders not be used in advertising or12 * publicity pertaining to distribution of the software without specific,13 * written prior permission. The copyright holders make no representations14 * about the suitability of this software for any purpose. It is provided "as15 * 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 NO19 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR20 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,21 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER22 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE23 * OF THIS SOFTWARE.24 *25 * Authors:26 * Keith Packard27 * 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_managed.h>41#include <drm/drm_modeset_helper_vtables.h>42#include <drm/drm_print.h>43#include <drm/drm_probe_helper.h>44#include <drm/drm_sysfs.h>45 46#include "drm_crtc_helper_internal.h"47 48/**49 * DOC: output probing helper overview50 *51 * This library provides some helper code for output probing. It provides an52 * implementation of the core &drm_connector_funcs.fill_modes interface with53 * drm_helper_probe_single_connector_modes().54 *55 * It also provides support for polling connectors with a work item and for56 * generic hotplug interrupt handling where the driver doesn't or cannot keep57 * track of a per-connector hpd interrupt.58 *59 * This helper library can be used independently of the modeset helper library.60 * Drivers can also overwrite different parts e.g. use their own hotplug61 * handling code to avoid probing unrelated outputs.62 *63 * The probe helpers share the function table structures with other display64 * helper libraries. See &struct drm_connector_helper_funcs for the details.65 */66 67static bool drm_kms_helper_poll = true;68module_param_named(poll, drm_kms_helper_poll, bool, 0600);69 70static enum drm_mode_status71drm_mode_validate_flag(const struct drm_display_mode *mode,72 int flags)73{74 if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&75 !(flags & DRM_MODE_FLAG_INTERLACE))76 return MODE_NO_INTERLACE;77 78 if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&79 !(flags & DRM_MODE_FLAG_DBLSCAN))80 return MODE_NO_DBLESCAN;81 82 if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&83 !(flags & DRM_MODE_FLAG_3D_MASK))84 return MODE_NO_STEREO;85 86 return MODE_OK;87}88 89static int90drm_mode_validate_pipeline(struct drm_display_mode *mode,91 struct drm_connector *connector,92 struct drm_modeset_acquire_ctx *ctx,93 enum drm_mode_status *status)94{95 struct drm_device *dev = connector->dev;96 struct drm_encoder *encoder;97 int ret;98 99 /* Step 1: Validate against connector */100 ret = drm_connector_mode_valid(connector, mode, ctx, status);101 if (ret || *status != MODE_OK)102 return ret;103 104 /* Step 2: Validate against encoders and crtcs */105 drm_connector_for_each_possible_encoder(connector, encoder) {106 struct drm_bridge *bridge;107 struct drm_crtc *crtc;108 109 *status = drm_encoder_mode_valid(encoder, mode);110 if (*status != MODE_OK) {111 /* No point in continuing for crtc check as this encoder112 * will not accept the mode anyway. If all encoders113 * reject the mode then, at exit, ret will not be114 * MODE_OK. */115 continue;116 }117 118 bridge = drm_bridge_chain_get_first_bridge(encoder);119 *status = drm_bridge_chain_mode_valid(bridge,120 &connector->display_info,121 mode);122 if (*status != MODE_OK) {123 /* There is also no point in continuing for crtc check124 * here. */125 continue;126 }127 128 drm_for_each_crtc(crtc, dev) {129 if (!drm_encoder_crtc_ok(encoder, crtc))130 continue;131 132 *status = drm_crtc_mode_valid(crtc, mode);133 if (*status == MODE_OK) {134 /* If we get to this point there is at least135 * one combination of encoder+crtc that works136 * for this mode. Lets return now. */137 return 0;138 }139 }140 }141 142 return 0;143}144 145static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)146{147 struct drm_cmdline_mode *cmdline_mode;148 struct drm_display_mode *mode;149 150 cmdline_mode = &connector->cmdline_mode;151 if (!cmdline_mode->specified)152 return 0;153 154 /* Only add a GTF mode if we find no matching probed modes */155 list_for_each_entry(mode, &connector->probed_modes, head) {156 if (mode->hdisplay != cmdline_mode->xres ||157 mode->vdisplay != cmdline_mode->yres)158 continue;159 160 if (cmdline_mode->refresh_specified) {161 /* The probed mode's vrefresh is set until later */162 if (drm_mode_vrefresh(mode) != cmdline_mode->refresh)163 continue;164 }165 166 /* Mark the matching mode as being preferred by the user */167 mode->type |= DRM_MODE_TYPE_USERDEF;168 return 0;169 }170 171 mode = drm_mode_create_from_cmdline_mode(connector->dev,172 cmdline_mode);173 if (mode == NULL)174 return 0;175 176 drm_mode_probed_add(connector, mode);177 return 1;178}179 180enum drm_mode_status drm_crtc_mode_valid(struct drm_crtc *crtc,181 const struct drm_display_mode *mode)182{183 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;184 185 if (!crtc_funcs || !crtc_funcs->mode_valid)186 return MODE_OK;187 188 return crtc_funcs->mode_valid(crtc, mode);189}190 191enum drm_mode_status drm_encoder_mode_valid(struct drm_encoder *encoder,192 const struct drm_display_mode *mode)193{194 const struct drm_encoder_helper_funcs *encoder_funcs =195 encoder->helper_private;196 197 if (!encoder_funcs || !encoder_funcs->mode_valid)198 return MODE_OK;199 200 return encoder_funcs->mode_valid(encoder, mode);201}202 203int204drm_connector_mode_valid(struct drm_connector *connector,205 struct drm_display_mode *mode,206 struct drm_modeset_acquire_ctx *ctx,207 enum drm_mode_status *status)208{209 const struct drm_connector_helper_funcs *connector_funcs =210 connector->helper_private;211 int ret = 0;212 213 if (!connector_funcs)214 *status = MODE_OK;215 else if (connector_funcs->mode_valid_ctx)216 ret = connector_funcs->mode_valid_ctx(connector, mode, ctx,217 status);218 else if (connector_funcs->mode_valid)219 *status = connector_funcs->mode_valid(connector, mode);220 else221 *status = MODE_OK;222 223 return ret;224}225 226static void drm_kms_helper_disable_hpd(struct drm_device *dev)227{228 struct drm_connector *connector;229 struct drm_connector_list_iter conn_iter;230 231 drm_connector_list_iter_begin(dev, &conn_iter);232 drm_for_each_connector_iter(connector, &conn_iter) {233 const struct drm_connector_helper_funcs *funcs =234 connector->helper_private;235 236 if (funcs && funcs->disable_hpd)237 funcs->disable_hpd(connector);238 }239 drm_connector_list_iter_end(&conn_iter);240}241 242static bool drm_kms_helper_enable_hpd(struct drm_device *dev)243{244 bool poll = false;245 struct drm_connector *connector;246 struct drm_connector_list_iter conn_iter;247 248 drm_connector_list_iter_begin(dev, &conn_iter);249 drm_for_each_connector_iter(connector, &conn_iter) {250 const struct drm_connector_helper_funcs *funcs =251 connector->helper_private;252 253 if (funcs && funcs->enable_hpd)254 funcs->enable_hpd(connector);255 256 if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |257 DRM_CONNECTOR_POLL_DISCONNECT))258 poll = true;259 }260 drm_connector_list_iter_end(&conn_iter);261 262 return poll;263}264 265#define DRM_OUTPUT_POLL_PERIOD (10*HZ)266static void reschedule_output_poll_work(struct drm_device *dev)267{268 unsigned long delay = DRM_OUTPUT_POLL_PERIOD;269 270 if (dev->mode_config.delayed_event)271 /*272 * FIXME:273 *274 * Use short (1s) delay to handle the initial delayed event.275 * This delay should not be needed, but Optimus/nouveau will276 * fail in a mysterious way if the delayed event is handled as277 * soon as possible like it is done in278 * drm_helper_probe_single_connector_modes() in case the poll279 * was enabled before.280 */281 delay = HZ;282 283 schedule_delayed_work(&dev->mode_config.output_poll_work, delay);284}285 286/**287 * drm_kms_helper_poll_enable - re-enable output polling.288 * @dev: drm_device289 *290 * This function re-enables the output polling work, after it has been291 * temporarily disabled using drm_kms_helper_poll_disable(), for example over292 * suspend/resume.293 *294 * Drivers can call this helper from their device resume implementation. It is295 * not an error to call this even when output polling isn't enabled.296 *297 * If device polling was never initialized before, this call will trigger a298 * warning and return.299 *300 * Note that calls to enable and disable polling must be strictly ordered, which301 * is automatically the case when they're only call from suspend/resume302 * callbacks.303 */304void drm_kms_helper_poll_enable(struct drm_device *dev)305{306 if (drm_WARN_ON_ONCE(dev, !dev->mode_config.poll_enabled) ||307 !drm_kms_helper_poll || dev->mode_config.poll_running)308 return;309 310 if (drm_kms_helper_enable_hpd(dev) ||311 dev->mode_config.delayed_event)312 reschedule_output_poll_work(dev);313 314 dev->mode_config.poll_running = true;315}316EXPORT_SYMBOL(drm_kms_helper_poll_enable);317 318/**319 * drm_kms_helper_poll_reschedule - reschedule the output polling work320 * @dev: drm_device321 *322 * This function reschedules the output polling work, after polling for a323 * connector has been enabled.324 *325 * Drivers must call this helper after enabling polling for a connector by326 * setting %DRM_CONNECTOR_POLL_CONNECT / %DRM_CONNECTOR_POLL_DISCONNECT flags327 * in drm_connector::polled. Note that after disabling polling by clearing these328 * flags for a connector will stop the output polling work automatically if329 * the polling is disabled for all other connectors as well.330 *331 * The function can be called only after polling has been enabled by calling332 * drm_kms_helper_poll_init() / drm_kms_helper_poll_enable().333 */334void drm_kms_helper_poll_reschedule(struct drm_device *dev)335{336 if (dev->mode_config.poll_running)337 reschedule_output_poll_work(dev);338}339EXPORT_SYMBOL(drm_kms_helper_poll_reschedule);340 341static enum drm_connector_status342drm_helper_probe_detect_ctx(struct drm_connector *connector, bool force)343{344 const struct drm_connector_helper_funcs *funcs = connector->helper_private;345 struct drm_modeset_acquire_ctx ctx;346 int ret;347 348 drm_modeset_acquire_init(&ctx, 0);349 350retry:351 ret = drm_modeset_lock(&connector->dev->mode_config.connection_mutex, &ctx);352 if (!ret) {353 if (funcs->detect_ctx)354 ret = funcs->detect_ctx(connector, &ctx, force);355 else if (connector->funcs->detect)356 ret = connector->funcs->detect(connector, force);357 else358 ret = connector_status_connected;359 }360 361 if (ret == -EDEADLK) {362 drm_modeset_backoff(&ctx);363 goto retry;364 }365 366 if (WARN_ON(ret < 0))367 ret = connector_status_unknown;368 369 if (ret != connector->status)370 connector->epoch_counter += 1;371 372 drm_modeset_drop_locks(&ctx);373 drm_modeset_acquire_fini(&ctx);374 375 return ret;376}377 378/**379 * drm_helper_probe_detect - probe connector status380 * @connector: connector to probe381 * @ctx: acquire_ctx, or NULL to let this function handle locking.382 * @force: Whether destructive probe operations should be performed.383 *384 * This function calls the detect callbacks of the connector.385 * This function returns &drm_connector_status, or386 * if @ctx is set, it might also return -EDEADLK.387 */388int389drm_helper_probe_detect(struct drm_connector *connector,390 struct drm_modeset_acquire_ctx *ctx,391 bool force)392{393 const struct drm_connector_helper_funcs *funcs = connector->helper_private;394 struct drm_device *dev = connector->dev;395 int ret;396 397 if (!ctx)398 return drm_helper_probe_detect_ctx(connector, force);399 400 ret = drm_modeset_lock(&dev->mode_config.connection_mutex, ctx);401 if (ret)402 return ret;403 404 if (funcs->detect_ctx)405 ret = funcs->detect_ctx(connector, ctx, force);406 else if (connector->funcs->detect)407 ret = connector->funcs->detect(connector, force);408 else409 ret = connector_status_connected;410 411 if (ret != connector->status)412 connector->epoch_counter += 1;413 414 return ret;415}416EXPORT_SYMBOL(drm_helper_probe_detect);417 418static int drm_helper_probe_get_modes(struct drm_connector *connector)419{420 const struct drm_connector_helper_funcs *connector_funcs =421 connector->helper_private;422 int count;423 424 count = connector_funcs->get_modes(connector);425 426 /* The .get_modes() callback should not return negative values. */427 if (count < 0) {428 drm_err(connector->dev, ".get_modes() returned %pe\n",429 ERR_PTR(count));430 count = 0;431 }432 433 /*434 * Fallback for when DDC probe failed in drm_get_edid() and thus skipped435 * override/firmware EDID.436 */437 if (count == 0 && connector->status == connector_status_connected)438 count = drm_edid_override_connector_update(connector);439 440 return count;441}442 443static int __drm_helper_update_and_validate(struct drm_connector *connector,444 uint32_t maxX, uint32_t maxY,445 struct drm_modeset_acquire_ctx *ctx)446{447 struct drm_device *dev = connector->dev;448 struct drm_display_mode *mode;449 int mode_flags = 0;450 int ret;451 452 drm_connector_list_update(connector);453 454 if (connector->interlace_allowed)455 mode_flags |= DRM_MODE_FLAG_INTERLACE;456 if (connector->doublescan_allowed)457 mode_flags |= DRM_MODE_FLAG_DBLSCAN;458 if (connector->stereo_allowed)459 mode_flags |= DRM_MODE_FLAG_3D_MASK;460 461 list_for_each_entry(mode, &connector->modes, head) {462 if (mode->status != MODE_OK)463 continue;464 465 mode->status = drm_mode_validate_driver(dev, mode);466 if (mode->status != MODE_OK)467 continue;468 469 mode->status = drm_mode_validate_size(mode, maxX, maxY);470 if (mode->status != MODE_OK)471 continue;472 473 mode->status = drm_mode_validate_flag(mode, mode_flags);474 if (mode->status != MODE_OK)475 continue;476 477 mode->status = drm_mode_validate_ycbcr420(mode, connector);478 if (mode->status != MODE_OK)479 continue;480 481 ret = drm_mode_validate_pipeline(mode, connector, ctx,482 &mode->status);483 if (ret) {484 drm_dbg_kms(dev,485 "drm_mode_validate_pipeline failed: %d\n",486 ret);487 488 if (drm_WARN_ON_ONCE(dev, ret != -EDEADLK))489 mode->status = MODE_ERROR;490 else491 return -EDEADLK;492 }493 }494 495 return 0;496}497 498/**499 * drm_helper_probe_single_connector_modes - get complete set of display modes500 * @connector: connector to probe501 * @maxX: max width for modes502 * @maxY: max height for modes503 *504 * Based on the helper callbacks implemented by @connector in struct505 * &drm_connector_helper_funcs try to detect all valid modes. Modes will first506 * be added to the connector's probed_modes list, then culled (based on validity507 * and the @maxX, @maxY parameters) and put into the normal modes list.508 *509 * Intended to be used as a generic implementation of the510 * &drm_connector_funcs.fill_modes() vfunc for drivers that use the CRTC helpers511 * for output mode filtering and detection.512 *513 * The basic procedure is as follows514 *515 * 1. All modes currently on the connector's modes list are marked as stale516 *517 * 2. New modes are added to the connector's probed_modes list with518 * drm_mode_probed_add(). New modes start their life with status as OK.519 * Modes are added from a single source using the following priority order.520 *521 * - &drm_connector_helper_funcs.get_modes vfunc522 * - if the connector status is connector_status_connected, standard523 * VESA DMT modes up to 1024x768 are automatically added524 * (drm_add_modes_noedid())525 *526 * Finally modes specified via the kernel command line (video=...) are527 * added in addition to what the earlier probes produced528 * (drm_helper_probe_add_cmdline_mode()). These modes are generated529 * using the VESA GTF/CVT formulas.530 *531 * 3. Modes are moved from the probed_modes list to the modes list. Potential532 * duplicates are merged together (see drm_connector_list_update()).533 * After this step the probed_modes list will be empty again.534 *535 * 4. Any non-stale mode on the modes list then undergoes validation536 *537 * - drm_mode_validate_basic() performs basic sanity checks538 * - drm_mode_validate_size() filters out modes larger than @maxX and @maxY539 * (if specified)540 * - drm_mode_validate_flag() checks the modes against basic connector541 * capabilities (interlace_allowed,doublescan_allowed,stereo_allowed)542 * - the optional &drm_connector_helper_funcs.mode_valid or543 * &drm_connector_helper_funcs.mode_valid_ctx helpers can perform driver544 * and/or sink specific checks545 * - the optional &drm_crtc_helper_funcs.mode_valid,546 * &drm_bridge_funcs.mode_valid and &drm_encoder_helper_funcs.mode_valid547 * helpers can perform driver and/or source specific checks which are also548 * enforced by the modeset/atomic helpers549 *550 * 5. Any mode whose status is not OK is pruned from the connector's modes list,551 * accompanied by a debug message indicating the reason for the mode's552 * rejection (see drm_mode_prune_invalid()).553 *554 * Returns:555 * The number of modes found on @connector.556 */557int drm_helper_probe_single_connector_modes(struct drm_connector *connector,558 uint32_t maxX, uint32_t maxY)559{560 struct drm_device *dev = connector->dev;561 struct drm_display_mode *mode;562 int count = 0, ret;563 enum drm_connector_status old_status;564 struct drm_modeset_acquire_ctx ctx;565 566 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));567 568 drm_modeset_acquire_init(&ctx, 0);569 570 drm_dbg_kms(dev, "[CONNECTOR:%d:%s]\n", connector->base.id,571 connector->name);572 573retry:574 ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);575 if (ret == -EDEADLK) {576 drm_modeset_backoff(&ctx);577 goto retry;578 } else579 WARN_ON(ret < 0);580 581 /* set all old modes to the stale state */582 list_for_each_entry(mode, &connector->modes, head)583 mode->status = MODE_STALE;584 585 old_status = connector->status;586 587 if (connector->force) {588 if (connector->force == DRM_FORCE_ON ||589 connector->force == DRM_FORCE_ON_DIGITAL)590 connector->status = connector_status_connected;591 else592 connector->status = connector_status_disconnected;593 if (connector->funcs->force)594 connector->funcs->force(connector);595 } else {596 ret = drm_helper_probe_detect(connector, &ctx, true);597 598 if (ret == -EDEADLK) {599 drm_modeset_backoff(&ctx);600 goto retry;601 } else if (WARN(ret < 0, "Invalid return value %i for connector detection\n", ret))602 ret = connector_status_unknown;603 604 connector->status = ret;605 }606 607 /*608 * Normally either the driver's hpd code or the poll loop should609 * pick up any changes and fire the hotplug event. But if610 * userspace sneaks in a probe, we might miss a change. Hence611 * check here, and if anything changed start the hotplug code.612 */613 if (old_status != connector->status) {614 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n",615 connector->base.id, 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 fb621 * helpers, and so expects that we do not hold any622 * locks. Fire up the poll struct instead, it will623 * 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 polling634 * 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_dbg_kms(dev, "[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 1.4a655 * 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 that674 * all detachable sinks shall support 640x480 @60Hz as a fail safe675 * mode. If all modes were pruned, perhaps because they need more676 * lanes or a higher pixel clock than available, at least try to add677 * 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_dbg_kms(dev, "[CONNECTOR:%d:%s] probed modes:\n",700 connector->base.id, connector->name);701 702 list_for_each_entry(mode, &connector->modes, head) {703 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);704 drm_dbg_kms(dev, "Probed mode: " DRM_MODE_FMT "\n",705 DRM_MODE_ARG(mode));706 }707 708 return count;709}710EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);711 712/**713 * drm_kms_helper_hotplug_event - fire off KMS hotplug events714 * @dev: drm_device whose connector state changed715 *716 * This function fires off the uevent for userspace and also calls the717 * client hotplug function, which is most commonly used to inform the fbdev718 * emulation code and allow it to update the fbcon output configuration.719 *720 * Drivers should call this from their hotplug handling code when a change is721 * detected. Note that this function does not do any output detection of its722 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the723 * driver already.724 *725 * This function must be called from process context with no mode726 * setting locks held.727 *728 * If only a single connector has changed, consider calling729 * drm_kms_helper_connector_hotplug_event() instead.730 */731void drm_kms_helper_hotplug_event(struct drm_device *dev)732{733 drm_sysfs_hotplug_event(dev);734 drm_client_dev_hotplug(dev);735}736EXPORT_SYMBOL(drm_kms_helper_hotplug_event);737 738/**739 * drm_kms_helper_connector_hotplug_event - fire off a KMS connector hotplug event740 * @connector: drm_connector which has changed741 *742 * This is the same as drm_kms_helper_hotplug_event(), except it fires a more743 * fine-grained uevent for a single connector.744 */745void drm_kms_helper_connector_hotplug_event(struct drm_connector *connector)746{747 struct drm_device *dev = connector->dev;748 749 drm_sysfs_connector_hotplug_event(connector);750 drm_client_dev_hotplug(dev);751}752EXPORT_SYMBOL(drm_kms_helper_connector_hotplug_event);753 754static void output_poll_execute(struct work_struct *work)755{756 struct delayed_work *delayed_work = to_delayed_work(work);757 struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);758 struct drm_connector *connector;759 struct drm_connector_list_iter conn_iter;760 enum drm_connector_status old_status;761 bool repoll = false, changed;762 u64 old_epoch_counter;763 764 if (!dev->mode_config.poll_enabled)765 return;766 767 /* Pick up any changes detected by the probe functions. */768 changed = dev->mode_config.delayed_event;769 dev->mode_config.delayed_event = false;770 771 if (!drm_kms_helper_poll) {772 if (dev->mode_config.poll_running) {773 drm_kms_helper_disable_hpd(dev);774 dev->mode_config.poll_running = false;775 }776 goto out;777 }778 779 if (!mutex_trylock(&dev->mode_config.mutex)) {780 repoll = true;781 goto out;782 }783 784 drm_connector_list_iter_begin(dev, &conn_iter);785 drm_for_each_connector_iter(connector, &conn_iter) {786 /* Ignore forced connectors. */787 if (connector->force)788 continue;789 790 /* Ignore HPD capable connectors and connectors where we don't791 * want any hotplug detection at all for polling. */792 if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD)793 continue;794 795 old_status = connector->status;796 /* if we are connected and don't want to poll for disconnect797 skip it */798 if (old_status == connector_status_connected &&799 !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))800 continue;801 802 repoll = true;803 804 old_epoch_counter = connector->epoch_counter;805 connector->status = drm_helper_probe_detect(connector, NULL, false);806 if (old_epoch_counter != connector->epoch_counter) {807 const char *old, *new;808 809 /*810 * The poll work sets force=false when calling detect so811 * that drivers can avoid to do disruptive tests (e.g.812 * when load detect cycles could cause flickering on813 * other, running displays). This bears the risk that we814 * flip-flop between unknown here in the poll work and815 * the real state when userspace forces a full detect816 * call after receiving a hotplug event due to this817 * change.818 *819 * Hence clamp an unknown detect status to the old820 * value.821 */822 if (connector->status == connector_status_unknown) {823 connector->status = old_status;824 continue;825 }826 827 old = drm_get_connector_status_name(old_status);828 new = drm_get_connector_status_name(connector->status);829 830 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n",831 connector->base.id, connector->name,832 old, new);833 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] epoch counter %llu -> %llu\n",834 connector->base.id, connector->name,835 old_epoch_counter, connector->epoch_counter);836 837 changed = true;838 }839 }840 drm_connector_list_iter_end(&conn_iter);841 842 mutex_unlock(&dev->mode_config.mutex);843 844out:845 if (changed)846 drm_kms_helper_hotplug_event(dev);847 848 if (repoll)849 schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);850}851 852/**853 * drm_kms_helper_is_poll_worker - is %current task an output poll worker?854 *855 * Determine if %current task is an output poll worker. This can be used856 * to select distinct code paths for output polling versus other contexts.857 *858 * One use case is to avoid a deadlock between the output poll worker and859 * the autosuspend worker wherein the latter waits for polling to finish860 * upon calling drm_kms_helper_poll_disable(), while the former waits for861 * runtime suspend to finish upon calling pm_runtime_get_sync() in a862 * connector ->detect hook.863 */864bool drm_kms_helper_is_poll_worker(void)865{866 struct work_struct *work = current_work();867 868 return work && work->func == output_poll_execute;869}870EXPORT_SYMBOL(drm_kms_helper_is_poll_worker);871 872/**873 * drm_kms_helper_poll_disable - disable output polling874 * @dev: drm_device875 *876 * This function disables the output polling work.877 *878 * Drivers can call this helper from their device suspend implementation. It is879 * not an error to call this even when output polling isn't enabled or already880 * disabled. Polling is re-enabled by calling drm_kms_helper_poll_enable().881 *882 * If however, the polling was never initialized, this call will trigger a883 * warning and return.884 *885 * Note that calls to enable and disable polling must be strictly ordered, which886 * is automatically the case when they're only call from suspend/resume887 * callbacks.888 */889void drm_kms_helper_poll_disable(struct drm_device *dev)890{891 if (drm_WARN_ON(dev, !dev->mode_config.poll_enabled))892 return;893 894 if (dev->mode_config.poll_running)895 drm_kms_helper_disable_hpd(dev);896 897 cancel_delayed_work_sync(&dev->mode_config.output_poll_work);898 899 dev->mode_config.poll_running = false;900}901EXPORT_SYMBOL(drm_kms_helper_poll_disable);902 903/**904 * drm_kms_helper_poll_init - initialize and enable output polling905 * @dev: drm_device906 *907 * This function initializes and then also enables output polling support for908 * @dev. Drivers which do not have reliable hotplug support in hardware can use909 * this helper infrastructure to regularly poll such connectors for changes in910 * their connection state.911 *912 * Drivers can control which connectors are polled by setting the913 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On914 * connectors where probing live outputs can result in visual distortion drivers915 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.916 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are917 * completely ignored by the polling logic.918 *919 * Note that a connector can be both polled and probed from the hotplug handler,920 * in case the hotplug interrupt is known to be unreliable.921 */922void drm_kms_helper_poll_init(struct drm_device *dev)923{924 INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);925 dev->mode_config.poll_enabled = true;926 927 drm_kms_helper_poll_enable(dev);928}929EXPORT_SYMBOL(drm_kms_helper_poll_init);930 931/**932 * drm_kms_helper_poll_fini - disable output polling and clean it up933 * @dev: drm_device934 */935void drm_kms_helper_poll_fini(struct drm_device *dev)936{937 if (!dev->mode_config.poll_enabled)938 return;939 940 drm_kms_helper_poll_disable(dev);941 942 dev->mode_config.poll_enabled = false;943}944EXPORT_SYMBOL(drm_kms_helper_poll_fini);945 946static void drm_kms_helper_poll_init_release(struct drm_device *dev, void *res)947{948 drm_kms_helper_poll_fini(dev);949}950 951/**952 * drmm_kms_helper_poll_init - initialize and enable output polling953 * @dev: drm_device954 *955 * This function initializes and then also enables output polling support for956 * @dev similar to drm_kms_helper_poll_init(). Polling will automatically be957 * cleaned up when the DRM device goes away.958 *959 * See drm_kms_helper_poll_init() for more information.960 *961 * Returns:962 * 0 on success, or a negative errno code otherwise.963 */964int drmm_kms_helper_poll_init(struct drm_device *dev)965{966 drm_kms_helper_poll_init(dev);967 968 return drmm_add_action_or_reset(dev, drm_kms_helper_poll_init_release, dev);969}970EXPORT_SYMBOL(drmm_kms_helper_poll_init);971 972static bool check_connector_changed(struct drm_connector *connector)973{974 struct drm_device *dev = connector->dev;975 enum drm_connector_status old_status;976 u64 old_epoch_counter;977 978 /* Only handle HPD capable connectors. */979 drm_WARN_ON(dev, !(connector->polled & DRM_CONNECTOR_POLL_HPD));980 981 drm_WARN_ON(dev, !mutex_is_locked(&dev->mode_config.mutex));982 983 old_status = connector->status;984 old_epoch_counter = connector->epoch_counter;985 connector->status = drm_helper_probe_detect(connector, NULL, false);986 987 if (old_epoch_counter == connector->epoch_counter) {988 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Same epoch counter %llu\n",989 connector->base.id,990 connector->name,991 connector->epoch_counter);992 993 return false;994 }995 996 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] status updated from %s to %s\n",997 connector->base.id,998 connector->name,999 drm_get_connector_status_name(old_status),1000 drm_get_connector_status_name(connector->status));1001 1002 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Changed epoch counter %llu => %llu\n",1003 connector->base.id,1004 connector->name,1005 old_epoch_counter,1006 connector->epoch_counter);1007 1008 return true;1009}1010 1011/**1012 * drm_connector_helper_hpd_irq_event - hotplug processing1013 * @connector: drm_connector1014 *1015 * Drivers can use this helper function to run a detect cycle on a connector1016 * which has the DRM_CONNECTOR_POLL_HPD flag set in its &polled member.1017 *1018 * This helper function is useful for drivers which can track hotplug1019 * interrupts for a single connector. Drivers that want to send a1020 * hotplug event for all connectors or can't track hotplug interrupts1021 * per connector need to use drm_helper_hpd_irq_event().1022 *1023 * This function must be called from process context with no mode1024 * setting locks held.1025 *1026 * Note that a connector can be both polled and probed from the hotplug1027 * handler, in case the hotplug interrupt is known to be unreliable.1028 *1029 * Returns:1030 * A boolean indicating whether the connector status changed or not1031 */1032bool drm_connector_helper_hpd_irq_event(struct drm_connector *connector)1033{1034 struct drm_device *dev = connector->dev;1035 bool changed;1036 1037 mutex_lock(&dev->mode_config.mutex);1038 changed = check_connector_changed(connector);1039 mutex_unlock(&dev->mode_config.mutex);1040 1041 if (changed) {1042 drm_kms_helper_connector_hotplug_event(connector);1043 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] Sent hotplug event\n",1044 connector->base.id,1045 connector->name);1046 }1047 1048 return changed;1049}1050EXPORT_SYMBOL(drm_connector_helper_hpd_irq_event);1051 1052/**1053 * drm_helper_hpd_irq_event - hotplug processing1054 * @dev: drm_device1055 *1056 * Drivers can use this helper function to run a detect cycle on all connectors1057 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All1058 * other connectors are ignored, which is useful to avoid reprobing fixed1059 * panels.1060 *1061 * This helper function is useful for drivers which can't or don't track hotplug1062 * interrupts for each connector.1063 *1064 * Drivers which support hotplug interrupts for each connector individually and1065 * which have a more fine-grained detect logic can use1066 * drm_connector_helper_hpd_irq_event(). Alternatively, they should bypass this1067 * code and directly call drm_kms_helper_hotplug_event() in case the connector1068 * state changed.1069 *1070 * This function must be called from process context with no mode1071 * setting locks held.1072 *1073 * Note that a connector can be both polled and probed from the hotplug handler,1074 * in case the hotplug interrupt is known to be unreliable.1075 *1076 * Returns:1077 * A boolean indicating whether the connector status changed or not1078 */1079bool drm_helper_hpd_irq_event(struct drm_device *dev)1080{1081 struct drm_connector *connector, *first_changed_connector = NULL;1082 struct drm_connector_list_iter conn_iter;1083 int changed = 0;1084 1085 if (!dev->mode_config.poll_enabled)1086 return false;1087 1088 mutex_lock(&dev->mode_config.mutex);1089 drm_connector_list_iter_begin(dev, &conn_iter);1090 drm_for_each_connector_iter(connector, &conn_iter) {1091 /* Only handle HPD capable connectors. */1092 if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))1093 continue;1094 1095 if (check_connector_changed(connector)) {1096 if (!first_changed_connector) {1097 drm_connector_get(connector);1098 first_changed_connector = connector;1099 }1100 1101 changed++;1102 }1103 }1104 drm_connector_list_iter_end(&conn_iter);1105 mutex_unlock(&dev->mode_config.mutex);1106 1107 if (changed == 1)1108 drm_kms_helper_connector_hotplug_event(first_changed_connector);1109 else if (changed > 0)1110 drm_kms_helper_hotplug_event(dev);1111 1112 if (first_changed_connector)1113 drm_connector_put(first_changed_connector);1114 1115 return changed;1116}1117EXPORT_SYMBOL(drm_helper_hpd_irq_event);1118 1119/**1120 * drm_crtc_helper_mode_valid_fixed - Validates a display mode1121 * @crtc: the crtc1122 * @mode: the mode to validate1123 * @fixed_mode: the display hardware's mode1124 *1125 * Returns:1126 * MODE_OK on success, or another mode-status code otherwise.1127 */1128enum drm_mode_status drm_crtc_helper_mode_valid_fixed(struct drm_crtc *crtc,1129 const struct drm_display_mode *mode,1130 const struct drm_display_mode *fixed_mode)1131{1132 if (mode->hdisplay != fixed_mode->hdisplay && mode->vdisplay != fixed_mode->vdisplay)1133 return MODE_ONE_SIZE;1134 else if (mode->hdisplay != fixed_mode->hdisplay)1135 return MODE_ONE_WIDTH;1136 else if (mode->vdisplay != fixed_mode->vdisplay)1137 return MODE_ONE_HEIGHT;1138 1139 return MODE_OK;1140}1141EXPORT_SYMBOL(drm_crtc_helper_mode_valid_fixed);1142 1143/**1144 * drm_connector_helper_get_modes_fixed - Duplicates a display mode for a connector1145 * @connector: the connector1146 * @fixed_mode: the display hardware's mode1147 *1148 * This function duplicates a display modes for a connector. Drivers for hardware1149 * that only supports a single fixed mode can use this function in their connector's1150 * get_modes helper.1151 *1152 * Returns:1153 * The number of created modes.1154 */1155int drm_connector_helper_get_modes_fixed(struct drm_connector *connector,1156 const struct drm_display_mode *fixed_mode)1157{1158 struct drm_device *dev = connector->dev;1159 struct drm_display_mode *mode;1160 1161 mode = drm_mode_duplicate(dev, fixed_mode);1162 if (!mode) {1163 drm_err(dev, "Failed to duplicate mode " DRM_MODE_FMT "\n",1164 DRM_MODE_ARG(fixed_mode));1165 return 0;1166 }1167 1168 if (mode->name[0] == '\0')1169 drm_mode_set_name(mode);1170 1171 mode->type |= DRM_MODE_TYPE_PREFERRED;1172 drm_mode_probed_add(connector, mode);1173 1174 if (mode->width_mm)1175 connector->display_info.width_mm = mode->width_mm;1176 if (mode->height_mm)1177 connector->display_info.height_mm = mode->height_mm;1178 1179 return 1;1180}1181EXPORT_SYMBOL(drm_connector_helper_get_modes_fixed);1182 1183/**1184 * drm_connector_helper_get_modes - Read EDID and update connector.1185 * @connector: The connector1186 *1187 * Read the EDID using drm_edid_read() (which requires that connector->ddc is1188 * set), and update the connector using the EDID.1189 *1190 * This can be used as the "default" connector helper .get_modes() hook if the1191 * driver does not need any special processing. This is sets the example what1192 * custom .get_modes() hooks should do regarding EDID read and connector update.1193 *1194 * Returns: Number of modes.1195 */1196int drm_connector_helper_get_modes(struct drm_connector *connector)1197{1198 const struct drm_edid *drm_edid;1199 int count;1200 1201 drm_edid = drm_edid_read(connector);1202 1203 /*1204 * Unconditionally update the connector. If the EDID was read1205 * successfully, fill in the connector information derived from the1206 * EDID. Otherwise, if the EDID is NULL, clear the connector1207 * information.1208 */1209 drm_edid_connector_update(connector, drm_edid);1210 1211 count = drm_edid_connector_add_modes(connector);1212 1213 drm_edid_free(drm_edid);1214 1215 return count;1216}1217EXPORT_SYMBOL(drm_connector_helper_get_modes);1218 1219/**1220 * drm_connector_helper_tv_get_modes - Fills the modes availables to a TV connector1221 * @connector: The connector1222 *1223 * Fills the available modes for a TV connector based on the supported1224 * TV modes, and the default mode expressed by the kernel command line.1225 *1226 * This can be used as the default TV connector helper .get_modes() hook1227 * if the driver does not need any special processing.1228 *1229 * Returns:1230 * The number of modes added to the connector.1231 */1232int drm_connector_helper_tv_get_modes(struct drm_connector *connector)1233{1234 struct drm_device *dev = connector->dev;1235 struct drm_property *tv_mode_property =1236 dev->mode_config.tv_mode_property;1237 struct drm_cmdline_mode *cmdline = &connector->cmdline_mode;1238 unsigned int ntsc_modes = BIT(DRM_MODE_TV_MODE_NTSC) |1239 BIT(DRM_MODE_TV_MODE_NTSC_443) |1240 BIT(DRM_MODE_TV_MODE_NTSC_J) |1241 BIT(DRM_MODE_TV_MODE_PAL_M);1242 unsigned int pal_modes = BIT(DRM_MODE_TV_MODE_PAL) |1243 BIT(DRM_MODE_TV_MODE_PAL_N) |1244 BIT(DRM_MODE_TV_MODE_SECAM);1245 unsigned int tv_modes[2] = { UINT_MAX, UINT_MAX };1246 unsigned int i, supported_tv_modes = 0;1247 1248 if (!tv_mode_property)1249 return 0;1250 1251 for (i = 0; i < tv_mode_property->num_values; i++)1252 supported_tv_modes |= BIT(tv_mode_property->values[i]);1253 1254 if (((supported_tv_modes & ntsc_modes) &&1255 (supported_tv_modes & pal_modes)) ||1256 (supported_tv_modes & BIT(DRM_MODE_TV_MODE_MONOCHROME))) {1257 uint64_t default_mode;1258 1259 if (drm_object_property_get_default_value(&connector->base,1260 tv_mode_property,1261 &default_mode))1262 return 0;1263 1264 if (cmdline->tv_mode_specified)1265 default_mode = cmdline->tv_mode;1266 1267 if (BIT(default_mode) & ntsc_modes) {1268 tv_modes[0] = DRM_MODE_TV_MODE_NTSC;1269 tv_modes[1] = DRM_MODE_TV_MODE_PAL;1270 } else {1271 tv_modes[0] = DRM_MODE_TV_MODE_PAL;1272 tv_modes[1] = DRM_MODE_TV_MODE_NTSC;1273 }1274 } else if (supported_tv_modes & ntsc_modes) {1275 tv_modes[0] = DRM_MODE_TV_MODE_NTSC;1276 } else if (supported_tv_modes & pal_modes) {1277 tv_modes[0] = DRM_MODE_TV_MODE_PAL;1278 } else {1279 return 0;1280 }1281 1282 for (i = 0; i < ARRAY_SIZE(tv_modes); i++) {1283 struct drm_display_mode *mode;1284 1285 if (tv_modes[i] == DRM_MODE_TV_MODE_NTSC)1286 mode = drm_mode_analog_ntsc_480i(dev);1287 else if (tv_modes[i] == DRM_MODE_TV_MODE_PAL)1288 mode = drm_mode_analog_pal_576i(dev);1289 else1290 break;1291 if (!mode)1292 return i;1293 if (!i)1294 mode->type |= DRM_MODE_TYPE_PREFERRED;1295 drm_mode_probed_add(connector, mode);1296 }1297 1298 return i;1299}1300EXPORT_SYMBOL(drm_connector_helper_tv_get_modes);1301 1302/**1303 * drm_connector_helper_detect_from_ddc - Read EDID and detect connector status.1304 * @connector: The connector1305 * @ctx: Acquire context1306 * @force: Perform screen-destructive operations, if necessary1307 *1308 * Detects the connector status by reading the EDID using drm_probe_ddc(),1309 * which requires connector->ddc to be set. Returns connector_status_connected1310 * on success or connector_status_disconnected on failure.1311 *1312 * Returns:1313 * The connector status as defined by enum drm_connector_status.1314 */1315int drm_connector_helper_detect_from_ddc(struct drm_connector *connector,1316 struct drm_modeset_acquire_ctx *ctx,1317 bool force)1318{1319 struct i2c_adapter *ddc = connector->ddc;1320 1321 if (!ddc)1322 return connector_status_unknown;1323 1324 if (drm_probe_ddc(ddc))1325 return connector_status_connected;1326 1327 return connector_status_disconnected;1328}1329EXPORT_SYMBOL(drm_connector_helper_detect_from_ddc);1330