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v4.6
  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/drmP.h>
 36#include <drm/drm_crtc.h>
 37#include <drm/drm_fourcc.h>
 38#include <drm/drm_crtc_helper.h>
 39#include <drm/drm_fb_helper.h>
 40#include <drm/drm_edid.h>
 41
 42/**
 43 * DOC: output probing helper overview
 44 *
 45 * This library provides some helper code for output probing. It provides an
 46 * implementation of the core connector->fill_modes interface with
 47 * drm_helper_probe_single_connector_modes.
 48 *
 49 * It also provides support for polling connectors with a work item and for
 50 * generic hotplug interrupt handling where the driver doesn't or cannot keep
 51 * track of a per-connector hpd interrupt.
 52 *
 53 * This helper library can be used independently of the modeset helper library.
 54 * Drivers can also overwrite different parts e.g. use their own hotplug
 55 * handling code to avoid probing unrelated outputs.
 56 *
 57 * The probe helpers share the function table structures with other display
 58 * helper libraries. See struct &drm_connector_helper_funcs for the details.
 59 */
 60
 61static bool drm_kms_helper_poll = true;
 62module_param_named(poll, drm_kms_helper_poll, bool, 0600);
 63
 64static enum drm_mode_status
 65drm_mode_validate_flag(const struct drm_display_mode *mode,
 66		       int flags)
 67{
 68	if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
 69	    !(flags & DRM_MODE_FLAG_INTERLACE))
 70		return MODE_NO_INTERLACE;
 71
 72	if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
 73	    !(flags & DRM_MODE_FLAG_DBLSCAN))
 74		return MODE_NO_DBLESCAN;
 75
 76	if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
 77	    !(flags & DRM_MODE_FLAG_3D_MASK))
 78		return MODE_NO_STEREO;
 79
 80	return MODE_OK;
 81}
 82
 83static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)
 84{
 
 85	struct drm_display_mode *mode;
 86
 87	if (!connector->cmdline_mode.specified)
 
 88		return 0;
 89
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 90	mode = drm_mode_create_from_cmdline_mode(connector->dev,
 91						 &connector->cmdline_mode);
 92	if (mode == NULL)
 93		return 0;
 94
 95	drm_mode_probed_add(connector, mode);
 96	return 1;
 97}
 98
 99#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
100/**
101 * drm_kms_helper_poll_enable_locked - re-enable output polling.
102 * @dev: drm_device
103 *
104 * This function re-enables the output polling work without
105 * locking the mode_config mutex.
106 *
107 * This is like drm_kms_helper_poll_enable() however it is to be
108 * called from a context where the mode_config mutex is locked
109 * already.
110 */
111void drm_kms_helper_poll_enable_locked(struct drm_device *dev)
112{
113	bool poll = false;
114	struct drm_connector *connector;
 
115
116	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
117
118	if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
119		return;
120
121	drm_for_each_connector(connector, dev) {
122		if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
123					 DRM_CONNECTOR_POLL_DISCONNECT))
124			poll = true;
125	}
126
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
127	if (poll)
128		schedule_delayed_work(&dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
129}
130EXPORT_SYMBOL(drm_kms_helper_poll_enable_locked);
131
 
 
 
 
 
 
 
 
132/**
133 * drm_helper_probe_single_connector_modes - get complete set of display modes
134 * @connector: connector to probe
135 * @maxX: max width for modes
136 * @maxY: max height for modes
137 *
138 * Based on the helper callbacks implemented by @connector in struct
139 * &drm_connector_helper_funcs try to detect all valid modes.  Modes will first
140 * be added to the connector's probed_modes list, then culled (based on validity
141 * and the @maxX, @maxY parameters) and put into the normal modes list.
142 *
143 * Intended to be used as a generic implementation of the ->fill_modes()
144 * @connector vfunc for drivers that use the CRTC helpers for output mode
145 * filtering and detection.
146 *
147 * The basic procedure is as follows
148 *
149 * 1. All modes currently on the connector's modes list are marked as stale
150 *
151 * 2. New modes are added to the connector's probed_modes list with
152 *    drm_mode_probed_add(). New modes start their life with status as OK.
153 *    Modes are added from a single source using the following priority order.
154 *
155 *    - debugfs 'override_edid' (used for testing only)
156 *    - firmware EDID (drm_load_edid_firmware())
157 *    - connector helper ->get_modes() vfunc
158 *    - if the connector status is connector_status_connected, standard
159 *      VESA DMT modes up to 1024x768 are automatically added
160 *      (drm_add_modes_noedid())
161 *
162 *    Finally modes specified via the kernel command line (video=...) are
163 *    added in addition to what the earlier probes produced
164 *    (drm_helper_probe_add_cmdline_mode()). These modes are generated
165 *    using the VESA GTF/CVT formulas.
166 *
167 * 3. Modes are moved from the probed_modes list to the modes list. Potential
168 *    duplicates are merged together (see drm_mode_connector_list_update()).
169 *    After this step the probed_modes list will be empty again.
170 *
171 * 4. Any non-stale mode on the modes list then undergoes validation
172 *
173 *    - drm_mode_validate_basic() performs basic sanity checks
174 *    - drm_mode_validate_size() filters out modes larger than @maxX and @maxY
175 *      (if specified)
176 *    - drm_mode_validate_flag() checks the modes againt basic connector
177 *      capabilites (interlace_allowed,doublescan_allowed,stereo_allowed)
178 *    - the optional connector ->mode_valid() helper can perform driver and/or
179 *      hardware specific checks
180 *
181 * 5. Any mode whose status is not OK is pruned from the connector's modes list,
182 *    accompanied by a debug message indicating the reason for the mode's
183 *    rejection (see drm_mode_prune_invalid()).
184 *
185 * Returns:
186 * The number of modes found on @connector.
187 */
188int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
189					    uint32_t maxX, uint32_t maxY)
190{
191	struct drm_device *dev = connector->dev;
192	struct drm_display_mode *mode;
193	const struct drm_connector_helper_funcs *connector_funcs =
194		connector->helper_private;
195	int count = 0;
196	int mode_flags = 0;
197	bool verbose_prune = true;
198	enum drm_connector_status old_status;
199
200	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
201
202	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
203			connector->name);
204	/* set all old modes to the stale state */
205	list_for_each_entry(mode, &connector->modes, head)
206		mode->status = MODE_STALE;
207
208	old_status = connector->status;
209
210	if (connector->force) {
211		if (connector->force == DRM_FORCE_ON ||
212		    connector->force == DRM_FORCE_ON_DIGITAL)
213			connector->status = connector_status_connected;
214		else
215			connector->status = connector_status_disconnected;
216		if (connector->funcs->force)
217			connector->funcs->force(connector);
218	} else {
219		connector->status = connector->funcs->detect(connector, true);
220	}
221
222	/*
223	 * Normally either the driver's hpd code or the poll loop should
224	 * pick up any changes and fire the hotplug event. But if
225	 * userspace sneaks in a probe, we might miss a change. Hence
226	 * check here, and if anything changed start the hotplug code.
227	 */
228	if (old_status != connector->status) {
229		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
230			      connector->base.id,
231			      connector->name,
232			      drm_get_connector_status_name(old_status),
233			      drm_get_connector_status_name(connector->status));
234
235		/*
236		 * The hotplug event code might call into the fb
237		 * helpers, and so expects that we do not hold any
238		 * locks. Fire up the poll struct instead, it will
239		 * disable itself again.
240		 */
241		dev->mode_config.delayed_event = true;
242		if (dev->mode_config.poll_enabled)
243			schedule_delayed_work(&dev->mode_config.output_poll_work,
244					      0);
245	}
246
247	/* Re-enable polling in case the global poll config changed. */
248	if (drm_kms_helper_poll != dev->mode_config.poll_running)
249		drm_kms_helper_poll_enable_locked(dev);
250
251	dev->mode_config.poll_running = drm_kms_helper_poll;
252
253	if (connector->status == connector_status_disconnected) {
254		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",
255			connector->base.id, connector->name);
256		drm_mode_connector_update_edid_property(connector, NULL);
257		verbose_prune = false;
258		goto prune;
259	}
260
261	if (connector->override_edid) {
262		struct edid *edid = (struct edid *) connector->edid_blob_ptr->data;
263
264		count = drm_add_edid_modes(connector, edid);
265		drm_edid_to_eld(connector, edid);
266	} else {
267#ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE
268		count = drm_load_edid_firmware(connector);
269		if (count == 0)
270#endif
271			count = (*connector_funcs->get_modes)(connector);
272	}
273
274	if (count == 0 && connector->status == connector_status_connected)
275		count = drm_add_modes_noedid(connector, 1024, 768);
276	count += drm_helper_probe_add_cmdline_mode(connector);
277	if (count == 0)
278		goto prune;
279
280	drm_mode_connector_list_update(connector);
281
282	if (connector->interlace_allowed)
283		mode_flags |= DRM_MODE_FLAG_INTERLACE;
284	if (connector->doublescan_allowed)
285		mode_flags |= DRM_MODE_FLAG_DBLSCAN;
286	if (connector->stereo_allowed)
287		mode_flags |= DRM_MODE_FLAG_3D_MASK;
288
289	list_for_each_entry(mode, &connector->modes, head) {
290		if (mode->status == MODE_OK)
291			mode->status = drm_mode_validate_basic(mode);
292
293		if (mode->status == MODE_OK)
294			mode->status = drm_mode_validate_size(mode, maxX, maxY);
295
296		if (mode->status == MODE_OK)
297			mode->status = drm_mode_validate_flag(mode, mode_flags);
298
299		if (mode->status == MODE_OK && connector_funcs->mode_valid)
300			mode->status = connector_funcs->mode_valid(connector,
301								   mode);
302	}
303
304prune:
305	drm_mode_prune_invalid(dev, &connector->modes, verbose_prune);
306
307	if (list_empty(&connector->modes))
308		return 0;
309
310	list_for_each_entry(mode, &connector->modes, head)
311		mode->vrefresh = drm_mode_vrefresh(mode);
312
313	drm_mode_sort(&connector->modes);
314
315	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id,
316			connector->name);
317	list_for_each_entry(mode, &connector->modes, head) {
318		drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
319		drm_mode_debug_printmodeline(mode);
320	}
321
322	return count;
323}
324EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
325
326/**
327 * drm_kms_helper_hotplug_event - fire off KMS hotplug events
328 * @dev: drm_device whose connector state changed
329 *
330 * This function fires off the uevent for userspace and also calls the
331 * output_poll_changed function, which is most commonly used to inform the fbdev
332 * emulation code and allow it to update the fbcon output configuration.
333 *
334 * Drivers should call this from their hotplug handling code when a change is
335 * detected. Note that this function does not do any output detection of its
336 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
337 * driver already.
338 *
339 * This function must be called from process context with no mode
340 * setting locks held.
341 */
342void drm_kms_helper_hotplug_event(struct drm_device *dev)
343{
344	/* send a uevent + call fbdev */
345	drm_sysfs_hotplug_event(dev);
346	if (dev->mode_config.funcs->output_poll_changed)
347		dev->mode_config.funcs->output_poll_changed(dev);
348}
349EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
350
351static void output_poll_execute(struct work_struct *work)
352{
353	struct delayed_work *delayed_work = to_delayed_work(work);
354	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
355	struct drm_connector *connector;
356	enum drm_connector_status old_status;
357	bool repoll = false, changed;
358
359	/* Pick up any changes detected by the probe functions. */
360	changed = dev->mode_config.delayed_event;
361	dev->mode_config.delayed_event = false;
362
363	if (!drm_kms_helper_poll)
364		goto out;
365
366	mutex_lock(&dev->mode_config.mutex);
 
 
 
 
367	drm_for_each_connector(connector, dev) {
368
369		/* Ignore forced connectors. */
370		if (connector->force)
371			continue;
372
373		/* Ignore HPD capable connectors and connectors where we don't
374		 * want any hotplug detection at all for polling. */
375		if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD)
376			continue;
377
378		old_status = connector->status;
379		/* if we are connected and don't want to poll for disconnect
380		   skip it */
381		if (old_status == connector_status_connected &&
382		    !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
383			continue;
384
385		repoll = true;
386
387		connector->status = connector->funcs->detect(connector, false);
388		if (old_status != connector->status) {
389			const char *old, *new;
390
391			/*
392			 * The poll work sets force=false when calling detect so
393			 * that drivers can avoid to do disruptive tests (e.g.
394			 * when load detect cycles could cause flickering on
395			 * other, running displays). This bears the risk that we
396			 * flip-flop between unknown here in the poll work and
397			 * the real state when userspace forces a full detect
398			 * call after receiving a hotplug event due to this
399			 * change.
400			 *
401			 * Hence clamp an unknown detect status to the old
402			 * value.
403			 */
404			if (connector->status == connector_status_unknown) {
405				connector->status = old_status;
406				continue;
407			}
408
409			old = drm_get_connector_status_name(old_status);
410			new = drm_get_connector_status_name(connector->status);
411
412			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] "
413				      "status updated from %s to %s\n",
414				      connector->base.id,
415				      connector->name,
416				      old, new);
417
418			changed = true;
419		}
420	}
421
422	mutex_unlock(&dev->mode_config.mutex);
423
424out:
425	if (changed)
426		drm_kms_helper_hotplug_event(dev);
427
428	if (repoll)
429		schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
430}
431
432/**
433 * drm_kms_helper_poll_disable - disable output polling
434 * @dev: drm_device
435 *
436 * This function disables the output polling work.
437 *
438 * Drivers can call this helper from their device suspend implementation. It is
439 * not an error to call this even when output polling isn't enabled or arlready
440 * disabled.
441 */
442void drm_kms_helper_poll_disable(struct drm_device *dev)
443{
444	if (!dev->mode_config.poll_enabled)
445		return;
446	cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
447}
448EXPORT_SYMBOL(drm_kms_helper_poll_disable);
449
450/**
451 * drm_kms_helper_poll_enable - re-enable output polling.
452 * @dev: drm_device
453 *
454 * This function re-enables the output polling work.
455 *
456 * Drivers can call this helper from their device resume implementation. It is
457 * an error to call this when the output polling support has not yet been set
458 * up.
459 */
460void drm_kms_helper_poll_enable(struct drm_device *dev)
461{
462	mutex_lock(&dev->mode_config.mutex);
463	drm_kms_helper_poll_enable_locked(dev);
464	mutex_unlock(&dev->mode_config.mutex);
465}
466EXPORT_SYMBOL(drm_kms_helper_poll_enable);
467
468/**
469 * drm_kms_helper_poll_init - initialize and enable output polling
470 * @dev: drm_device
471 *
472 * This function intializes and then also enables output polling support for
473 * @dev. Drivers which do not have reliable hotplug support in hardware can use
474 * this helper infrastructure to regularly poll such connectors for changes in
475 * their connection state.
476 *
477 * Drivers can control which connectors are polled by setting the
478 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
479 * connectors where probing live outputs can result in visual distortion drivers
480 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
481 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
482 * completely ignored by the polling logic.
483 *
484 * Note that a connector can be both polled and probed from the hotplug handler,
485 * in case the hotplug interrupt is known to be unreliable.
486 */
487void drm_kms_helper_poll_init(struct drm_device *dev)
488{
489	INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
490	dev->mode_config.poll_enabled = true;
491
492	drm_kms_helper_poll_enable(dev);
493}
494EXPORT_SYMBOL(drm_kms_helper_poll_init);
495
496/**
497 * drm_kms_helper_poll_fini - disable output polling and clean it up
498 * @dev: drm_device
499 */
500void drm_kms_helper_poll_fini(struct drm_device *dev)
501{
502	drm_kms_helper_poll_disable(dev);
503}
504EXPORT_SYMBOL(drm_kms_helper_poll_fini);
505
506/**
507 * drm_helper_hpd_irq_event - hotplug processing
508 * @dev: drm_device
509 *
510 * Drivers can use this helper function to run a detect cycle on all connectors
511 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
512 * other connectors are ignored, which is useful to avoid reprobing fixed
513 * panels.
514 *
515 * This helper function is useful for drivers which can't or don't track hotplug
516 * interrupts for each connector.
517 *
518 * Drivers which support hotplug interrupts for each connector individually and
519 * which have a more fine-grained detect logic should bypass this code and
520 * directly call drm_kms_helper_hotplug_event() in case the connector state
521 * changed.
522 *
523 * This function must be called from process context with no mode
524 * setting locks held.
525 *
526 * Note that a connector can be both polled and probed from the hotplug handler,
527 * in case the hotplug interrupt is known to be unreliable.
528 */
529bool drm_helper_hpd_irq_event(struct drm_device *dev)
530{
531	struct drm_connector *connector;
532	enum drm_connector_status old_status;
533	bool changed = false;
534
535	if (!dev->mode_config.poll_enabled)
536		return false;
537
538	mutex_lock(&dev->mode_config.mutex);
539	drm_for_each_connector(connector, dev) {
540
541		/* Only handle HPD capable connectors. */
542		if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
543			continue;
544
545		old_status = connector->status;
546
547		connector->status = connector->funcs->detect(connector, false);
548		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
549			      connector->base.id,
550			      connector->name,
551			      drm_get_connector_status_name(old_status),
552			      drm_get_connector_status_name(connector->status));
553		if (old_status != connector->status)
554			changed = true;
555	}
556
557	mutex_unlock(&dev->mode_config.mutex);
558
559	if (changed)
560		drm_kms_helper_hotplug_event(dev);
561
562	return changed;
563}
564EXPORT_SYMBOL(drm_helper_hpd_irq_event);
v4.10.11
  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/drmP.h>
 36#include <drm/drm_crtc.h>
 37#include <drm/drm_fourcc.h>
 38#include <drm/drm_crtc_helper.h>
 39#include <drm/drm_fb_helper.h>
 40#include <drm/drm_edid.h>
 41
 42/**
 43 * DOC: output probing helper overview
 44 *
 45 * This library provides some helper code for output probing. It provides an
 46 * implementation of the core connector->fill_modes interface with
 47 * drm_helper_probe_single_connector_modes.
 48 *
 49 * It also provides support for polling connectors with a work item and for
 50 * generic hotplug interrupt handling where the driver doesn't or cannot keep
 51 * track of a per-connector hpd interrupt.
 52 *
 53 * This helper library can be used independently of the modeset helper library.
 54 * Drivers can also overwrite different parts e.g. use their own hotplug
 55 * handling code to avoid probing unrelated outputs.
 56 *
 57 * The probe helpers share the function table structures with other display
 58 * helper libraries. See struct &drm_connector_helper_funcs for the details.
 59 */
 60
 61static bool drm_kms_helper_poll = true;
 62module_param_named(poll, drm_kms_helper_poll, bool, 0600);
 63
 64static enum drm_mode_status
 65drm_mode_validate_flag(const struct drm_display_mode *mode,
 66		       int flags)
 67{
 68	if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
 69	    !(flags & DRM_MODE_FLAG_INTERLACE))
 70		return MODE_NO_INTERLACE;
 71
 72	if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
 73	    !(flags & DRM_MODE_FLAG_DBLSCAN))
 74		return MODE_NO_DBLESCAN;
 75
 76	if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
 77	    !(flags & DRM_MODE_FLAG_3D_MASK))
 78		return MODE_NO_STEREO;
 79
 80	return MODE_OK;
 81}
 82
 83static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)
 84{
 85	struct drm_cmdline_mode *cmdline_mode;
 86	struct drm_display_mode *mode;
 87
 88	cmdline_mode = &connector->cmdline_mode;
 89	if (!cmdline_mode->specified)
 90		return 0;
 91
 92	/* Only add a GTF mode if we find no matching probed modes */
 93	list_for_each_entry(mode, &connector->probed_modes, head) {
 94		if (mode->hdisplay != cmdline_mode->xres ||
 95		    mode->vdisplay != cmdline_mode->yres)
 96			continue;
 97
 98		if (cmdline_mode->refresh_specified) {
 99			/* The probed mode's vrefresh is set until later */
100			if (drm_mode_vrefresh(mode) != cmdline_mode->refresh)
101				continue;
102		}
103
104		return 0;
105	}
106
107	mode = drm_mode_create_from_cmdline_mode(connector->dev,
108						 cmdline_mode);
109	if (mode == NULL)
110		return 0;
111
112	drm_mode_probed_add(connector, mode);
113	return 1;
114}
115
116#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
117/**
118 * drm_kms_helper_poll_enable_locked - re-enable output polling.
119 * @dev: drm_device
120 *
121 * This function re-enables the output polling work without
122 * locking the mode_config mutex.
123 *
124 * This is like drm_kms_helper_poll_enable() however it is to be
125 * called from a context where the mode_config mutex is locked
126 * already.
127 */
128void drm_kms_helper_poll_enable_locked(struct drm_device *dev)
129{
130	bool poll = false;
131	struct drm_connector *connector;
132	unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
133
134	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
135
136	if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
137		return;
138
139	drm_for_each_connector(connector, dev) {
140		if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
141					 DRM_CONNECTOR_POLL_DISCONNECT))
142			poll = true;
143	}
144
145	if (dev->mode_config.delayed_event) {
146		/*
147		 * FIXME:
148		 *
149		 * Use short (1s) delay to handle the initial delayed event.
150		 * This delay should not be needed, but Optimus/nouveau will
151		 * fail in a mysterious way if the delayed event is handled as
152		 * soon as possible like it is done in
153		 * drm_helper_probe_single_connector_modes() in case the poll
154		 * was enabled before.
155		 */
156		poll = true;
157		delay = HZ;
158	}
159
160	if (poll)
161		schedule_delayed_work(&dev->mode_config.output_poll_work, delay);
162}
163EXPORT_SYMBOL(drm_kms_helper_poll_enable_locked);
164
165static enum drm_connector_status
166drm_connector_detect(struct drm_connector *connector, bool force)
167{
168	return connector->funcs->detect ?
169		connector->funcs->detect(connector, force) :
170		connector_status_connected;
171}
172
173/**
174 * drm_helper_probe_single_connector_modes - get complete set of display modes
175 * @connector: connector to probe
176 * @maxX: max width for modes
177 * @maxY: max height for modes
178 *
179 * Based on the helper callbacks implemented by @connector in struct
180 * &drm_connector_helper_funcs try to detect all valid modes.  Modes will first
181 * be added to the connector's probed_modes list, then culled (based on validity
182 * and the @maxX, @maxY parameters) and put into the normal modes list.
183 *
184 * Intended to be used as a generic implementation of the ->fill_modes()
185 * @connector vfunc for drivers that use the CRTC helpers for output mode
186 * filtering and detection.
187 *
188 * The basic procedure is as follows
189 *
190 * 1. All modes currently on the connector's modes list are marked as stale
191 *
192 * 2. New modes are added to the connector's probed_modes list with
193 *    drm_mode_probed_add(). New modes start their life with status as OK.
194 *    Modes are added from a single source using the following priority order.
195 *
196 *    - debugfs 'override_edid' (used for testing only)
197 *    - firmware EDID (drm_load_edid_firmware())
198 *    - connector helper ->get_modes() vfunc
199 *    - if the connector status is connector_status_connected, standard
200 *      VESA DMT modes up to 1024x768 are automatically added
201 *      (drm_add_modes_noedid())
202 *
203 *    Finally modes specified via the kernel command line (video=...) are
204 *    added in addition to what the earlier probes produced
205 *    (drm_helper_probe_add_cmdline_mode()). These modes are generated
206 *    using the VESA GTF/CVT formulas.
207 *
208 * 3. Modes are moved from the probed_modes list to the modes list. Potential
209 *    duplicates are merged together (see drm_mode_connector_list_update()).
210 *    After this step the probed_modes list will be empty again.
211 *
212 * 4. Any non-stale mode on the modes list then undergoes validation
213 *
214 *    - drm_mode_validate_basic() performs basic sanity checks
215 *    - drm_mode_validate_size() filters out modes larger than @maxX and @maxY
216 *      (if specified)
217 *    - drm_mode_validate_flag() checks the modes againt basic connector
218 *      capabilites (interlace_allowed,doublescan_allowed,stereo_allowed)
219 *    - the optional connector ->mode_valid() helper can perform driver and/or
220 *      hardware specific checks
221 *
222 * 5. Any mode whose status is not OK is pruned from the connector's modes list,
223 *    accompanied by a debug message indicating the reason for the mode's
224 *    rejection (see drm_mode_prune_invalid()).
225 *
226 * Returns:
227 * The number of modes found on @connector.
228 */
229int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
230					    uint32_t maxX, uint32_t maxY)
231{
232	struct drm_device *dev = connector->dev;
233	struct drm_display_mode *mode;
234	const struct drm_connector_helper_funcs *connector_funcs =
235		connector->helper_private;
236	int count = 0;
237	int mode_flags = 0;
238	bool verbose_prune = true;
239	enum drm_connector_status old_status;
240
241	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
242
243	DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
244			connector->name);
245	/* set all old modes to the stale state */
246	list_for_each_entry(mode, &connector->modes, head)
247		mode->status = MODE_STALE;
248
249	old_status = connector->status;
250
251	if (connector->force) {
252		if (connector->force == DRM_FORCE_ON ||
253		    connector->force == DRM_FORCE_ON_DIGITAL)
254			connector->status = connector_status_connected;
255		else
256			connector->status = connector_status_disconnected;
257		if (connector->funcs->force)
258			connector->funcs->force(connector);
259	} else {
260		connector->status = drm_connector_detect(connector, true);
261	}
262
263	/*
264	 * Normally either the driver's hpd code or the poll loop should
265	 * pick up any changes and fire the hotplug event. But if
266	 * userspace sneaks in a probe, we might miss a change. Hence
267	 * check here, and if anything changed start the hotplug code.
268	 */
269	if (old_status != connector->status) {
270		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
271			      connector->base.id,
272			      connector->name,
273			      drm_get_connector_status_name(old_status),
274			      drm_get_connector_status_name(connector->status));
275
276		/*
277		 * The hotplug event code might call into the fb
278		 * helpers, and so expects that we do not hold any
279		 * locks. Fire up the poll struct instead, it will
280		 * disable itself again.
281		 */
282		dev->mode_config.delayed_event = true;
283		if (dev->mode_config.poll_enabled)
284			schedule_delayed_work(&dev->mode_config.output_poll_work,
285					      0);
286	}
287
288	/* Re-enable polling in case the global poll config changed. */
289	if (drm_kms_helper_poll != dev->mode_config.poll_running)
290		drm_kms_helper_poll_enable_locked(dev);
291
292	dev->mode_config.poll_running = drm_kms_helper_poll;
293
294	if (connector->status == connector_status_disconnected) {
295		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",
296			connector->base.id, connector->name);
297		drm_mode_connector_update_edid_property(connector, NULL);
298		verbose_prune = false;
299		goto prune;
300	}
301
302	if (connector->override_edid) {
303		struct edid *edid = (struct edid *) connector->edid_blob_ptr->data;
304
305		count = drm_add_edid_modes(connector, edid);
306		drm_edid_to_eld(connector, edid);
307	} else {
 
308		count = drm_load_edid_firmware(connector);
309		if (count == 0)
 
310			count = (*connector_funcs->get_modes)(connector);
311	}
312
313	if (count == 0 && connector->status == connector_status_connected)
314		count = drm_add_modes_noedid(connector, 1024, 768);
315	count += drm_helper_probe_add_cmdline_mode(connector);
316	if (count == 0)
317		goto prune;
318
319	drm_mode_connector_list_update(connector);
320
321	if (connector->interlace_allowed)
322		mode_flags |= DRM_MODE_FLAG_INTERLACE;
323	if (connector->doublescan_allowed)
324		mode_flags |= DRM_MODE_FLAG_DBLSCAN;
325	if (connector->stereo_allowed)
326		mode_flags |= DRM_MODE_FLAG_3D_MASK;
327
328	list_for_each_entry(mode, &connector->modes, head) {
329		if (mode->status == MODE_OK)
330			mode->status = drm_mode_validate_basic(mode);
331
332		if (mode->status == MODE_OK)
333			mode->status = drm_mode_validate_size(mode, maxX, maxY);
334
335		if (mode->status == MODE_OK)
336			mode->status = drm_mode_validate_flag(mode, mode_flags);
337
338		if (mode->status == MODE_OK && connector_funcs->mode_valid)
339			mode->status = connector_funcs->mode_valid(connector,
340								   mode);
341	}
342
343prune:
344	drm_mode_prune_invalid(dev, &connector->modes, verbose_prune);
345
346	if (list_empty(&connector->modes))
347		return 0;
348
349	list_for_each_entry(mode, &connector->modes, head)
350		mode->vrefresh = drm_mode_vrefresh(mode);
351
352	drm_mode_sort(&connector->modes);
353
354	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id,
355			connector->name);
356	list_for_each_entry(mode, &connector->modes, head) {
357		drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
358		drm_mode_debug_printmodeline(mode);
359	}
360
361	return count;
362}
363EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
364
365/**
366 * drm_kms_helper_hotplug_event - fire off KMS hotplug events
367 * @dev: drm_device whose connector state changed
368 *
369 * This function fires off the uevent for userspace and also calls the
370 * output_poll_changed function, which is most commonly used to inform the fbdev
371 * emulation code and allow it to update the fbcon output configuration.
372 *
373 * Drivers should call this from their hotplug handling code when a change is
374 * detected. Note that this function does not do any output detection of its
375 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
376 * driver already.
377 *
378 * This function must be called from process context with no mode
379 * setting locks held.
380 */
381void drm_kms_helper_hotplug_event(struct drm_device *dev)
382{
383	/* send a uevent + call fbdev */
384	drm_sysfs_hotplug_event(dev);
385	if (dev->mode_config.funcs->output_poll_changed)
386		dev->mode_config.funcs->output_poll_changed(dev);
387}
388EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
389
390static void output_poll_execute(struct work_struct *work)
391{
392	struct delayed_work *delayed_work = to_delayed_work(work);
393	struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
394	struct drm_connector *connector;
395	enum drm_connector_status old_status;
396	bool repoll = false, changed;
397
398	/* Pick up any changes detected by the probe functions. */
399	changed = dev->mode_config.delayed_event;
400	dev->mode_config.delayed_event = false;
401
402	if (!drm_kms_helper_poll)
403		goto out;
404
405	if (!mutex_trylock(&dev->mode_config.mutex)) {
406		repoll = true;
407		goto out;
408	}
409
410	drm_for_each_connector(connector, dev) {
411
412		/* Ignore forced connectors. */
413		if (connector->force)
414			continue;
415
416		/* Ignore HPD capable connectors and connectors where we don't
417		 * want any hotplug detection at all for polling. */
418		if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD)
419			continue;
420
421		old_status = connector->status;
422		/* if we are connected and don't want to poll for disconnect
423		   skip it */
424		if (old_status == connector_status_connected &&
425		    !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
426			continue;
427
428		repoll = true;
429
430		connector->status = drm_connector_detect(connector, false);
431		if (old_status != connector->status) {
432			const char *old, *new;
433
434			/*
435			 * The poll work sets force=false when calling detect so
436			 * that drivers can avoid to do disruptive tests (e.g.
437			 * when load detect cycles could cause flickering on
438			 * other, running displays). This bears the risk that we
439			 * flip-flop between unknown here in the poll work and
440			 * the real state when userspace forces a full detect
441			 * call after receiving a hotplug event due to this
442			 * change.
443			 *
444			 * Hence clamp an unknown detect status to the old
445			 * value.
446			 */
447			if (connector->status == connector_status_unknown) {
448				connector->status = old_status;
449				continue;
450			}
451
452			old = drm_get_connector_status_name(old_status);
453			new = drm_get_connector_status_name(connector->status);
454
455			DRM_DEBUG_KMS("[CONNECTOR:%d:%s] "
456				      "status updated from %s to %s\n",
457				      connector->base.id,
458				      connector->name,
459				      old, new);
460
461			changed = true;
462		}
463	}
464
465	mutex_unlock(&dev->mode_config.mutex);
466
467out:
468	if (changed)
469		drm_kms_helper_hotplug_event(dev);
470
471	if (repoll)
472		schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
473}
474
475/**
476 * drm_kms_helper_poll_disable - disable output polling
477 * @dev: drm_device
478 *
479 * This function disables the output polling work.
480 *
481 * Drivers can call this helper from their device suspend implementation. It is
482 * not an error to call this even when output polling isn't enabled or arlready
483 * disabled.
484 */
485void drm_kms_helper_poll_disable(struct drm_device *dev)
486{
487	if (!dev->mode_config.poll_enabled)
488		return;
489	cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
490}
491EXPORT_SYMBOL(drm_kms_helper_poll_disable);
492
493/**
494 * drm_kms_helper_poll_enable - re-enable output polling.
495 * @dev: drm_device
496 *
497 * This function re-enables the output polling work.
498 *
499 * Drivers can call this helper from their device resume implementation. It is
500 * an error to call this when the output polling support has not yet been set
501 * up.
502 */
503void drm_kms_helper_poll_enable(struct drm_device *dev)
504{
505	mutex_lock(&dev->mode_config.mutex);
506	drm_kms_helper_poll_enable_locked(dev);
507	mutex_unlock(&dev->mode_config.mutex);
508}
509EXPORT_SYMBOL(drm_kms_helper_poll_enable);
510
511/**
512 * drm_kms_helper_poll_init - initialize and enable output polling
513 * @dev: drm_device
514 *
515 * This function intializes and then also enables output polling support for
516 * @dev. Drivers which do not have reliable hotplug support in hardware can use
517 * this helper infrastructure to regularly poll such connectors for changes in
518 * their connection state.
519 *
520 * Drivers can control which connectors are polled by setting the
521 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
522 * connectors where probing live outputs can result in visual distortion drivers
523 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
524 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
525 * completely ignored by the polling logic.
526 *
527 * Note that a connector can be both polled and probed from the hotplug handler,
528 * in case the hotplug interrupt is known to be unreliable.
529 */
530void drm_kms_helper_poll_init(struct drm_device *dev)
531{
532	INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
533	dev->mode_config.poll_enabled = true;
534
535	drm_kms_helper_poll_enable(dev);
536}
537EXPORT_SYMBOL(drm_kms_helper_poll_init);
538
539/**
540 * drm_kms_helper_poll_fini - disable output polling and clean it up
541 * @dev: drm_device
542 */
543void drm_kms_helper_poll_fini(struct drm_device *dev)
544{
545	drm_kms_helper_poll_disable(dev);
546}
547EXPORT_SYMBOL(drm_kms_helper_poll_fini);
548
549/**
550 * drm_helper_hpd_irq_event - hotplug processing
551 * @dev: drm_device
552 *
553 * Drivers can use this helper function to run a detect cycle on all connectors
554 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
555 * other connectors are ignored, which is useful to avoid reprobing fixed
556 * panels.
557 *
558 * This helper function is useful for drivers which can't or don't track hotplug
559 * interrupts for each connector.
560 *
561 * Drivers which support hotplug interrupts for each connector individually and
562 * which have a more fine-grained detect logic should bypass this code and
563 * directly call drm_kms_helper_hotplug_event() in case the connector state
564 * changed.
565 *
566 * This function must be called from process context with no mode
567 * setting locks held.
568 *
569 * Note that a connector can be both polled and probed from the hotplug handler,
570 * in case the hotplug interrupt is known to be unreliable.
571 */
572bool drm_helper_hpd_irq_event(struct drm_device *dev)
573{
574	struct drm_connector *connector;
575	enum drm_connector_status old_status;
576	bool changed = false;
577
578	if (!dev->mode_config.poll_enabled)
579		return false;
580
581	mutex_lock(&dev->mode_config.mutex);
582	drm_for_each_connector(connector, dev) {
583
584		/* Only handle HPD capable connectors. */
585		if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
586			continue;
587
588		old_status = connector->status;
589
590		connector->status = drm_connector_detect(connector, false);
591		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
592			      connector->base.id,
593			      connector->name,
594			      drm_get_connector_status_name(old_status),
595			      drm_get_connector_status_name(connector->status));
596		if (old_status != connector->status)
597			changed = true;
598	}
599
600	mutex_unlock(&dev->mode_config.mutex);
601
602	if (changed)
603		drm_kms_helper_hotplug_event(dev);
604
605	return changed;
606}
607EXPORT_SYMBOL(drm_helper_hpd_irq_event);