2 * Copyright (c) 2006-2008 Intel Corporation
3 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
5 * DRM core CRTC related functions
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.
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
27 * Eric Anholt <eric@anholt.net>
28 * Dave Airlie <airlied@linux.ie>
29 * Jesse Barnes <jesse.barnes@intel.com>
32 #include <linux/export.h>
33 #include <linux/moduleparam.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>
43 * DOC: output probing helper overview
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.
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.
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.
58 static bool drm_kms_helper_poll
= true;
59 module_param_named(poll
, drm_kms_helper_poll
, bool, 0600);
61 static enum drm_mode_status
62 drm_mode_validate_flag(const struct drm_display_mode
*mode
,
65 if ((mode
->flags
& DRM_MODE_FLAG_INTERLACE
) &&
66 !(flags
& DRM_MODE_FLAG_INTERLACE
))
67 return MODE_NO_INTERLACE
;
69 if ((mode
->flags
& DRM_MODE_FLAG_DBLSCAN
) &&
70 !(flags
& DRM_MODE_FLAG_DBLSCAN
))
71 return MODE_NO_DBLESCAN
;
73 if ((mode
->flags
& DRM_MODE_FLAG_3D_MASK
) &&
74 !(flags
& DRM_MODE_FLAG_3D_MASK
))
75 return MODE_NO_STEREO
;
80 static int drm_helper_probe_add_cmdline_mode(struct drm_connector
*connector
)
82 struct drm_display_mode
*mode
;
84 if (!connector
->cmdline_mode
.specified
)
87 mode
= drm_mode_create_from_cmdline_mode(connector
->dev
,
88 &connector
->cmdline_mode
);
92 drm_mode_probed_add(connector
, mode
);
96 static int drm_helper_probe_single_connector_modes_merge_bits(struct drm_connector
*connector
,
97 uint32_t maxX
, uint32_t maxY
, bool merge_type_bits
)
99 struct drm_device
*dev
= connector
->dev
;
100 struct drm_display_mode
*mode
;
101 const struct drm_connector_helper_funcs
*connector_funcs
=
102 connector
->helper_private
;
105 bool verbose_prune
= true;
106 enum drm_connector_status old_status
;
108 WARN_ON(!mutex_is_locked(&dev
->mode_config
.mutex
));
110 DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector
->base
.id
,
112 /* set all modes to the unverified state */
113 list_for_each_entry(mode
, &connector
->modes
, head
)
114 mode
->status
= MODE_UNVERIFIED
;
116 if (connector
->force
) {
117 if (connector
->force
== DRM_FORCE_ON
||
118 connector
->force
== DRM_FORCE_ON_DIGITAL
)
119 connector
->status
= connector_status_connected
;
121 connector
->status
= connector_status_disconnected
;
122 if (connector
->funcs
->force
)
123 connector
->funcs
->force(connector
);
125 old_status
= connector
->status
;
127 connector
->status
= connector
->funcs
->detect(connector
, true);
130 * Normally either the driver's hpd code or the poll loop should
131 * pick up any changes and fire the hotplug event. But if
132 * userspace sneaks in a probe, we might miss a change. Hence
133 * check here, and if anything changed start the hotplug code.
135 if (old_status
!= connector
->status
) {
136 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %d to %d\n",
139 old_status
, connector
->status
);
142 * The hotplug event code might call into the fb
143 * helpers, and so expects that we do not hold any
144 * locks. Fire up the poll struct instead, it will
145 * disable itself again.
147 dev
->mode_config
.delayed_event
= true;
148 if (dev
->mode_config
.poll_enabled
)
149 schedule_delayed_work(&dev
->mode_config
.output_poll_work
,
154 /* Re-enable polling in case the global poll config changed. */
155 if (drm_kms_helper_poll
!= dev
->mode_config
.poll_running
)
156 drm_kms_helper_poll_enable(dev
);
158 dev
->mode_config
.poll_running
= drm_kms_helper_poll
;
160 if (connector
->status
== connector_status_disconnected
) {
161 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",
162 connector
->base
.id
, connector
->name
);
163 drm_mode_connector_update_edid_property(connector
, NULL
);
164 verbose_prune
= false;
168 #ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE
169 count
= drm_load_edid_firmware(connector
);
173 if (connector
->override_edid
) {
174 struct edid
*edid
= (struct edid
*) connector
->edid_blob_ptr
->data
;
176 count
= drm_add_edid_modes(connector
, edid
);
177 drm_edid_to_eld(connector
, edid
);
179 count
= (*connector_funcs
->get_modes
)(connector
);
182 if (count
== 0 && connector
->status
== connector_status_connected
)
183 count
= drm_add_modes_noedid(connector
, 1024, 768);
184 count
+= drm_helper_probe_add_cmdline_mode(connector
);
188 drm_mode_connector_list_update(connector
, merge_type_bits
);
190 if (connector
->interlace_allowed
)
191 mode_flags
|= DRM_MODE_FLAG_INTERLACE
;
192 if (connector
->doublescan_allowed
)
193 mode_flags
|= DRM_MODE_FLAG_DBLSCAN
;
194 if (connector
->stereo_allowed
)
195 mode_flags
|= DRM_MODE_FLAG_3D_MASK
;
197 list_for_each_entry(mode
, &connector
->modes
, head
) {
198 mode
->status
= drm_mode_validate_basic(mode
);
200 if (mode
->status
== MODE_OK
)
201 mode
->status
= drm_mode_validate_size(mode
, maxX
, maxY
);
203 if (mode
->status
== MODE_OK
)
204 mode
->status
= drm_mode_validate_flag(mode
, mode_flags
);
206 if (mode
->status
== MODE_OK
&& connector_funcs
->mode_valid
)
207 mode
->status
= connector_funcs
->mode_valid(connector
,
212 drm_mode_prune_invalid(dev
, &connector
->modes
, verbose_prune
);
214 if (list_empty(&connector
->modes
))
217 list_for_each_entry(mode
, &connector
->modes
, head
)
218 mode
->vrefresh
= drm_mode_vrefresh(mode
);
220 drm_mode_sort(&connector
->modes
);
222 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector
->base
.id
,
224 list_for_each_entry(mode
, &connector
->modes
, head
) {
225 drm_mode_set_crtcinfo(mode
, CRTC_INTERLACE_HALVE_V
);
226 drm_mode_debug_printmodeline(mode
);
233 * drm_helper_probe_single_connector_modes - get complete set of display modes
234 * @connector: connector to probe
235 * @maxX: max width for modes
236 * @maxY: max height for modes
238 * Based on the helper callbacks implemented by @connector try to detect all
239 * valid modes. Modes will first be added to the connector's probed_modes list,
240 * then culled (based on validity and the @maxX, @maxY parameters) and put into
241 * the normal modes list.
243 * Intended to be use as a generic implementation of the ->fill_modes()
244 * @connector vfunc for drivers that use the crtc helpers for output mode
245 * filtering and detection.
248 * The number of modes found on @connector.
250 int drm_helper_probe_single_connector_modes(struct drm_connector
*connector
,
251 uint32_t maxX
, uint32_t maxY
)
253 return drm_helper_probe_single_connector_modes_merge_bits(connector
, maxX
, maxY
, true);
255 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes
);
258 * drm_helper_probe_single_connector_modes_nomerge - get complete set of display modes
259 * @connector: connector to probe
260 * @maxX: max width for modes
261 * @maxY: max height for modes
263 * This operates like drm_hehlper_probe_single_connector_modes except it
264 * replaces the mode bits instead of merging them for preferred modes.
266 int drm_helper_probe_single_connector_modes_nomerge(struct drm_connector
*connector
,
267 uint32_t maxX
, uint32_t maxY
)
269 return drm_helper_probe_single_connector_modes_merge_bits(connector
, maxX
, maxY
, false);
271 EXPORT_SYMBOL(drm_helper_probe_single_connector_modes_nomerge
);
274 * drm_kms_helper_hotplug_event - fire off KMS hotplug events
275 * @dev: drm_device whose connector state changed
277 * This function fires off the uevent for userspace and also calls the
278 * output_poll_changed function, which is most commonly used to inform the fbdev
279 * emulation code and allow it to update the fbcon output configuration.
281 * Drivers should call this from their hotplug handling code when a change is
282 * detected. Note that this function does not do any output detection of its
283 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
286 * This function must be called from process context with no mode
287 * setting locks held.
289 void drm_kms_helper_hotplug_event(struct drm_device
*dev
)
291 /* send a uevent + call fbdev */
292 drm_sysfs_hotplug_event(dev
);
293 if (dev
->mode_config
.funcs
->output_poll_changed
)
294 dev
->mode_config
.funcs
->output_poll_changed(dev
);
296 EXPORT_SYMBOL(drm_kms_helper_hotplug_event
);
298 #define DRM_OUTPUT_POLL_PERIOD (10*HZ)
299 static void output_poll_execute(struct work_struct
*work
)
301 struct delayed_work
*delayed_work
= to_delayed_work(work
);
302 struct drm_device
*dev
= container_of(delayed_work
, struct drm_device
, mode_config
.output_poll_work
);
303 struct drm_connector
*connector
;
304 enum drm_connector_status old_status
;
305 bool repoll
= false, changed
;
307 /* Pick up any changes detected by the probe functions. */
308 changed
= dev
->mode_config
.delayed_event
;
309 dev
->mode_config
.delayed_event
= false;
311 if (!drm_kms_helper_poll
)
314 mutex_lock(&dev
->mode_config
.mutex
);
315 list_for_each_entry(connector
, &dev
->mode_config
.connector_list
, head
) {
317 /* Ignore forced connectors. */
318 if (connector
->force
)
321 /* Ignore HPD capable connectors and connectors where we don't
322 * want any hotplug detection at all for polling. */
323 if (!connector
->polled
|| connector
->polled
== DRM_CONNECTOR_POLL_HPD
)
326 old_status
= connector
->status
;
327 /* if we are connected and don't want to poll for disconnect
329 if (old_status
== connector_status_connected
&&
330 !(connector
->polled
& DRM_CONNECTOR_POLL_DISCONNECT
))
335 connector
->status
= connector
->funcs
->detect(connector
, false);
336 if (old_status
!= connector
->status
) {
337 const char *old
, *new;
340 * The poll work sets force=false when calling detect so
341 * that drivers can avoid to do disruptive tests (e.g.
342 * when load detect cycles could cause flickering on
343 * other, running displays). This bears the risk that we
344 * flip-flop between unknown here in the poll work and
345 * the real state when userspace forces a full detect
346 * call after receiving a hotplug event due to this
349 * Hence clamp an unknown detect status to the old
352 if (connector
->status
== connector_status_unknown
) {
353 connector
->status
= old_status
;
357 old
= drm_get_connector_status_name(old_status
);
358 new = drm_get_connector_status_name(connector
->status
);
360 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] "
361 "status updated from %s to %s\n",
370 mutex_unlock(&dev
->mode_config
.mutex
);
374 drm_kms_helper_hotplug_event(dev
);
377 schedule_delayed_work(delayed_work
, DRM_OUTPUT_POLL_PERIOD
);
381 * drm_kms_helper_poll_disable - disable output polling
384 * This function disables the output polling work.
386 * Drivers can call this helper from their device suspend implementation. It is
387 * not an error to call this even when output polling isn't enabled or arlready
390 void drm_kms_helper_poll_disable(struct drm_device
*dev
)
392 if (!dev
->mode_config
.poll_enabled
)
394 cancel_delayed_work_sync(&dev
->mode_config
.output_poll_work
);
396 EXPORT_SYMBOL(drm_kms_helper_poll_disable
);
399 * drm_kms_helper_poll_enable - re-enable output polling.
402 * This function re-enables the output polling work.
404 * Drivers can call this helper from their device resume implementation. It is
405 * an error to call this when the output polling support has not yet been set
408 void drm_kms_helper_poll_enable(struct drm_device
*dev
)
411 struct drm_connector
*connector
;
413 if (!dev
->mode_config
.poll_enabled
|| !drm_kms_helper_poll
)
416 list_for_each_entry(connector
, &dev
->mode_config
.connector_list
, head
) {
417 if (connector
->polled
& (DRM_CONNECTOR_POLL_CONNECT
|
418 DRM_CONNECTOR_POLL_DISCONNECT
))
423 schedule_delayed_work(&dev
->mode_config
.output_poll_work
, DRM_OUTPUT_POLL_PERIOD
);
425 EXPORT_SYMBOL(drm_kms_helper_poll_enable
);
428 * drm_kms_helper_poll_init - initialize and enable output polling
431 * This function intializes and then also enables output polling support for
432 * @dev. Drivers which do not have reliable hotplug support in hardware can use
433 * this helper infrastructure to regularly poll such connectors for changes in
434 * their connection state.
436 * Drivers can control which connectors are polled by setting the
437 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
438 * connectors where probing live outputs can result in visual distortion drivers
439 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
440 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
441 * completely ignored by the polling logic.
443 * Note that a connector can be both polled and probed from the hotplug handler,
444 * in case the hotplug interrupt is known to be unreliable.
446 void drm_kms_helper_poll_init(struct drm_device
*dev
)
448 INIT_DELAYED_WORK(&dev
->mode_config
.output_poll_work
, output_poll_execute
);
449 dev
->mode_config
.poll_enabled
= true;
451 drm_kms_helper_poll_enable(dev
);
453 EXPORT_SYMBOL(drm_kms_helper_poll_init
);
456 * drm_kms_helper_poll_fini - disable output polling and clean it up
459 void drm_kms_helper_poll_fini(struct drm_device
*dev
)
461 drm_kms_helper_poll_disable(dev
);
463 EXPORT_SYMBOL(drm_kms_helper_poll_fini
);
466 * drm_helper_hpd_irq_event - hotplug processing
469 * Drivers can use this helper function to run a detect cycle on all connectors
470 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
471 * other connectors are ignored, which is useful to avoid reprobing fixed
474 * This helper function is useful for drivers which can't or don't track hotplug
475 * interrupts for each connector.
477 * Drivers which support hotplug interrupts for each connector individually and
478 * which have a more fine-grained detect logic should bypass this code and
479 * directly call drm_kms_helper_hotplug_event() in case the connector state
482 * This function must be called from process context with no mode
483 * setting locks held.
485 * Note that a connector can be both polled and probed from the hotplug handler,
486 * in case the hotplug interrupt is known to be unreliable.
488 bool drm_helper_hpd_irq_event(struct drm_device
*dev
)
490 struct drm_connector
*connector
;
491 enum drm_connector_status old_status
;
492 bool changed
= false;
494 if (!dev
->mode_config
.poll_enabled
)
497 mutex_lock(&dev
->mode_config
.mutex
);
498 list_for_each_entry(connector
, &dev
->mode_config
.connector_list
, head
) {
500 /* Only handle HPD capable connectors. */
501 if (!(connector
->polled
& DRM_CONNECTOR_POLL_HPD
))
504 old_status
= connector
->status
;
506 connector
->status
= connector
->funcs
->detect(connector
, false);
507 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
510 drm_get_connector_status_name(old_status
),
511 drm_get_connector_status_name(connector
->status
));
512 if (old_status
!= connector
->status
)
516 mutex_unlock(&dev
->mode_config
.mutex
);
519 drm_kms_helper_hotplug_event(dev
);
523 EXPORT_SYMBOL(drm_helper_hpd_irq_event
);