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 <asm/param.h>
33#include <linux/export.h>
34#include <linux/moduleparam.h>
35
36#include <drm/drmP.h>
37#include <drm/drm_crtc.h>
38#include <drm/drm_fourcc.h>
39#include <drm/drm_crtc_helper.h>
40#include <drm/drm_fb_helper.h>
41#include <drm/drm_edid.h>
42
43/**
44 * DOC: output probing helper overview
45 *
46 * This library provides some helper code for output probing. It provides an
47 * implementation of the core connector->fill_modes interface with
48 * drm_helper_probe_single_connector_modes.
49 *
50 * It also provides support for polling connectors with a work item and for
51 * generic hotplug interrupt handling where the driver doesn't or cannot keep
52 * track of a per-connector hpd interrupt.
53 *
54 * This helper library can be used independently of the modeset helper library.
55 * Drivers can also overwrite different parts e.g. use their own hotplug
56 * handling code to avoid probing unrelated outputs.
57 */
58
59static bool drm_kms_helper_poll = true;
60module_param_named(poll, drm_kms_helper_poll, bool, 0600);
61
62static void drm_mode_validate_flag(struct drm_connector *connector,
63 int flags)
64{
65 struct drm_display_mode *mode;
66
67 if (flags == (DRM_MODE_FLAG_DBLSCAN | DRM_MODE_FLAG_INTERLACE |
68 DRM_MODE_FLAG_3D_MASK))
69 return;
70
71 list_for_each_entry(mode, &connector->modes, head) {
72 if ((mode->flags & DRM_MODE_FLAG_INTERLACE) &&
73 !(flags & DRM_MODE_FLAG_INTERLACE))
74 mode->status = MODE_NO_INTERLACE;
75 if ((mode->flags & DRM_MODE_FLAG_DBLSCAN) &&
76 !(flags & DRM_MODE_FLAG_DBLSCAN))
77 mode->status = MODE_NO_DBLESCAN;
78 if ((mode->flags & DRM_MODE_FLAG_3D_MASK) &&
79 !(flags & DRM_MODE_FLAG_3D_MASK))
80 mode->status = MODE_NO_STEREO;
81 }
82
83 return;
84}
85
86/**
87 * drm_helper_probe_single_connector_modes - get complete set of display modes
88 * @connector: connector to probe
89 * @maxX: max width for modes
90 * @maxY: max height for modes
91 *
92 * Based on the helper callbacks implemented by @connector try to detect all
93 * valid modes. Modes will first be added to the connector's probed_modes list,
94 * then culled (based on validity and the @maxX, @maxY parameters) and put into
95 * the normal modes list.
96 *
97 * Intended to be use as a generic implementation of the ->fill_modes()
98 * @connector vfunc for drivers that use the crtc helpers for output mode
99 * filtering and detection.
100 *
101 * Returns:
102 * The number of modes found on @connector.
103 */
104int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
105 uint32_t maxX, uint32_t maxY)
106{
107 struct drm_device *dev = connector->dev;
108 struct drm_display_mode *mode;
109 struct drm_connector_helper_funcs *connector_funcs =
110 connector->helper_private;
111 int count = 0;
112 int mode_flags = 0;
113 bool verbose_prune = true;
114
115 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
116
117 DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
118 drm_get_connector_name(connector));
119 /* set all modes to the unverified state */
120 list_for_each_entry(mode, &connector->modes, head)
121 mode->status = MODE_UNVERIFIED;
122
123 if (connector->force) {
124 if (connector->force == DRM_FORCE_ON)
125 connector->status = connector_status_connected;
126 else
127 connector->status = connector_status_disconnected;
128 if (connector->funcs->force)
129 connector->funcs->force(connector);
130 } else {
131 connector->status = connector->funcs->detect(connector, true);
132 }
133
134 /* Re-enable polling in case the global poll config changed. */
135 if (drm_kms_helper_poll != dev->mode_config.poll_running)
136 drm_kms_helper_poll_enable(dev);
137
138 dev->mode_config.poll_running = drm_kms_helper_poll;
139
140 if (connector->status == connector_status_disconnected) {
141 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] disconnected\n",
142 connector->base.id, drm_get_connector_name(connector));
143 drm_mode_connector_update_edid_property(connector, NULL);
144 verbose_prune = false;
145 goto prune;
146 }
147
148#ifdef CONFIG_DRM_LOAD_EDID_FIRMWARE
149 count = drm_load_edid_firmware(connector);
150 if (count == 0)
151#endif
152 count = (*connector_funcs->get_modes)(connector);
153
154 if (count == 0 && connector->status == connector_status_connected)
155 count = drm_add_modes_noedid(connector, 1024, 768);
156 if (count == 0)
157 goto prune;
158
159 drm_mode_connector_list_update(connector);
160
161 if (maxX && maxY)
162 drm_mode_validate_size(dev, &connector->modes, maxX, maxY);
163
164 if (connector->interlace_allowed)
165 mode_flags |= DRM_MODE_FLAG_INTERLACE;
166 if (connector->doublescan_allowed)
167 mode_flags |= DRM_MODE_FLAG_DBLSCAN;
168 if (connector->stereo_allowed)
169 mode_flags |= DRM_MODE_FLAG_3D_MASK;
170 drm_mode_validate_flag(connector, mode_flags);
171
172 list_for_each_entry(mode, &connector->modes, head) {
173 if (mode->status == MODE_OK)
174 mode->status = connector_funcs->mode_valid(connector,
175 mode);
176 }
177
178prune:
179 drm_mode_prune_invalid(dev, &connector->modes, verbose_prune);
180
181 if (list_empty(&connector->modes))
182 return 0;
183
184 list_for_each_entry(mode, &connector->modes, head)
185 mode->vrefresh = drm_mode_vrefresh(mode);
186
187 drm_mode_sort(&connector->modes);
188
189 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] probed modes :\n", connector->base.id,
190 drm_get_connector_name(connector));
191 list_for_each_entry(mode, &connector->modes, head) {
192 drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
193 drm_mode_debug_printmodeline(mode);
194 }
195
196 return count;
197}
198EXPORT_SYMBOL(drm_helper_probe_single_connector_modes);
199
200/**
201 * drm_kms_helper_hotplug_event - fire off KMS hotplug events
202 * @dev: drm_device whose connector state changed
203 *
204 * This function fires off the uevent for userspace and also calls the
205 * output_poll_changed function, which is most commonly used to inform the fbdev
206 * emulation code and allow it to update the fbcon output configuration.
207 *
208 * Drivers should call this from their hotplug handling code when a change is
209 * detected. Note that this function does not do any output detection of its
210 * own, like drm_helper_hpd_irq_event() does - this is assumed to be done by the
211 * driver already.
212 *
213 * This function must be called from process context with no mode
214 * setting locks held.
215 */
216void drm_kms_helper_hotplug_event(struct drm_device *dev)
217{
218 /* send a uevent + call fbdev */
219 drm_sysfs_hotplug_event(dev);
220 if (dev->mode_config.funcs->output_poll_changed)
221 dev->mode_config.funcs->output_poll_changed(dev);
222}
223EXPORT_SYMBOL(drm_kms_helper_hotplug_event);
224
225#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
226static void output_poll_execute(struct work_struct *work)
227{
228 struct delayed_work *delayed_work = to_delayed_work(work);
229 struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_work);
230 struct drm_connector *connector;
231 enum drm_connector_status old_status;
232 bool repoll = false, changed = false;
233
234 if (!drm_kms_helper_poll)
235 return;
236
237 mutex_lock(&dev->mode_config.mutex);
238 list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
239
240 /* Ignore forced connectors. */
241 if (connector->force)
242 continue;
243
244 /* Ignore HPD capable connectors and connectors where we don't
245 * want any hotplug detection at all for polling. */
246 if (!connector->polled || connector->polled == DRM_CONNECTOR_POLL_HPD)
247 continue;
248
249 repoll = true;
250
251 old_status = connector->status;
252 /* if we are connected and don't want to poll for disconnect
253 skip it */
254 if (old_status == connector_status_connected &&
255 !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT))
256 continue;
257
258 connector->status = connector->funcs->detect(connector, false);
259 if (old_status != connector->status) {
260 const char *old, *new;
261
262 old = drm_get_connector_status_name(old_status);
263 new = drm_get_connector_status_name(connector->status);
264
265 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] "
266 "status updated from %s to %s\n",
267 connector->base.id,
268 drm_get_connector_name(connector),
269 old, new);
270
271 changed = true;
272 }
273 }
274
275 mutex_unlock(&dev->mode_config.mutex);
276
277 if (changed)
278 drm_kms_helper_hotplug_event(dev);
279
280 if (repoll)
281 schedule_delayed_work(delayed_work, DRM_OUTPUT_POLL_PERIOD);
282}
283
284/**
285 * drm_kms_helper_poll_disable - disable output polling
286 * @dev: drm_device
287 *
288 * This function disables the output polling work.
289 *
290 * Drivers can call this helper from their device suspend implementation. It is
291 * not an error to call this even when output polling isn't enabled or arlready
292 * disabled.
293 */
294void drm_kms_helper_poll_disable(struct drm_device *dev)
295{
296 if (!dev->mode_config.poll_enabled)
297 return;
298 cancel_delayed_work_sync(&dev->mode_config.output_poll_work);
299}
300EXPORT_SYMBOL(drm_kms_helper_poll_disable);
301
302/**
303 * drm_kms_helper_poll_enable - re-enable output polling.
304 * @dev: drm_device
305 *
306 * This function re-enables the output polling work.
307 *
308 * Drivers can call this helper from their device resume implementation. It is
309 * an error to call this when the output polling support has not yet been set
310 * up.
311 */
312void drm_kms_helper_poll_enable(struct drm_device *dev)
313{
314 bool poll = false;
315 struct drm_connector *connector;
316
317 if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
318 return;
319
320 list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
321 if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT |
322 DRM_CONNECTOR_POLL_DISCONNECT))
323 poll = true;
324 }
325
326 if (poll)
327 schedule_delayed_work(&dev->mode_config.output_poll_work, DRM_OUTPUT_POLL_PERIOD);
328}
329EXPORT_SYMBOL(drm_kms_helper_poll_enable);
330
331/**
332 * drm_kms_helper_poll_init - initialize and enable output polling
333 * @dev: drm_device
334 *
335 * This function intializes and then also enables output polling support for
336 * @dev. Drivers which do not have reliable hotplug support in hardware can use
337 * this helper infrastructure to regularly poll such connectors for changes in
338 * their connection state.
339 *
340 * Drivers can control which connectors are polled by setting the
341 * DRM_CONNECTOR_POLL_CONNECT and DRM_CONNECTOR_POLL_DISCONNECT flags. On
342 * connectors where probing live outputs can result in visual distortion drivers
343 * should not set the DRM_CONNECTOR_POLL_DISCONNECT flag to avoid this.
344 * Connectors which have no flag or only DRM_CONNECTOR_POLL_HPD set are
345 * completely ignored by the polling logic.
346 *
347 * Note that a connector can be both polled and probed from the hotplug handler,
348 * in case the hotplug interrupt is known to be unreliable.
349 */
350void drm_kms_helper_poll_init(struct drm_device *dev)
351{
352 INIT_DELAYED_WORK(&dev->mode_config.output_poll_work, output_poll_execute);
353 dev->mode_config.poll_enabled = true;
354
355 drm_kms_helper_poll_enable(dev);
356}
357EXPORT_SYMBOL(drm_kms_helper_poll_init);
358
359/**
360 * drm_kms_helper_poll_fini - disable output polling and clean it up
361 * @dev: drm_device
362 */
363void drm_kms_helper_poll_fini(struct drm_device *dev)
364{
365 drm_kms_helper_poll_disable(dev);
366}
367EXPORT_SYMBOL(drm_kms_helper_poll_fini);
368
369/**
370 * drm_helper_hpd_irq_event - hotplug processing
371 * @dev: drm_device
372 *
373 * Drivers can use this helper function to run a detect cycle on all connectors
374 * which have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All
375 * other connectors are ignored, which is useful to avoid reprobing fixed
376 * panels.
377 *
378 * This helper function is useful for drivers which can't or don't track hotplug
379 * interrupts for each connector.
380 *
381 * Drivers which support hotplug interrupts for each connector individually and
382 * which have a more fine-grained detect logic should bypass this code and
383 * directly call drm_kms_helper_hotplug_event() in case the connector state
384 * changed.
385 *
386 * This function must be called from process context with no mode
387 * setting locks held.
388 *
389 * Note that a connector can be both polled and probed from the hotplug handler,
390 * in case the hotplug interrupt is known to be unreliable.
391 */
392bool drm_helper_hpd_irq_event(struct drm_device *dev)
393{
394 struct drm_connector *connector;
395 enum drm_connector_status old_status;
396 bool changed = false;
397
398 if (!dev->mode_config.poll_enabled)
399 return false;
400
401 mutex_lock(&dev->mode_config.mutex);
402 list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
403
404 /* Only handle HPD capable connectors. */
405 if (!(connector->polled & DRM_CONNECTOR_POLL_HPD))
406 continue;
407
408 old_status = connector->status;
409
410 connector->status = connector->funcs->detect(connector, false);
411 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n",
412 connector->base.id,
413 drm_get_connector_name(connector),
414 drm_get_connector_status_name(old_status),
415 drm_get_connector_status_name(connector->status));
416 if (old_status != connector->status)
417 changed = true;
418 }
419
420 mutex_unlock(&dev->mode_config.mutex);
421
422 if (changed)
423 drm_kms_helper_hotplug_event(dev);
424
425 return changed;
426}
427EXPORT_SYMBOL(drm_helper_hpd_irq_event);
428