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1 /*
2  * Copyright (c) 2006-2009 Red Hat Inc.
3  * Copyright (c) 2006-2008 Intel Corporation
4  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
5  *
6  * DRM framebuffer helper functions
7  *
8  * Permission to use, copy, modify, distribute, and sell this software and its
9  * documentation for any purpose is hereby granted without fee, provided that
10  * the above copyright notice appear in all copies and that both that copyright
11  * notice and this permission notice appear in supporting documentation, and
12  * that the name of the copyright holders not be used in advertising or
13  * publicity pertaining to distribution of the software without specific,
14  * written prior permission.  The copyright holders make no representations
15  * about the suitability of this software for any purpose.  It is provided "as
16  * is" without express or implied warranty.
17  *
18  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
20  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
21  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
22  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
23  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
24  * OF THIS SOFTWARE.
25  *
26  * Authors:
27  *      Dave Airlie <airlied@linux.ie>
28  *      Jesse Barnes <jesse.barnes@intel.com>
29  */
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31
32 #include <linux/kernel.h>
33 #include <linux/sysrq.h>
34 #include <linux/slab.h>
35 #include <linux/fb.h>
36 #include <linux/module.h>
37 #include <drm/drmP.h>
38 #include <drm/drm_crtc.h>
39 #include <drm/drm_fb_helper.h>
40 #include <drm/drm_crtc_helper.h>
41
42 static LIST_HEAD(kernel_fb_helper_list);
43
44 /**
45  * DOC: fbdev helpers
46  *
47  * The fb helper functions are useful to provide an fbdev on top of a drm kernel
48  * mode setting driver. They can be used mostly independently from the crtc
49  * helper functions used by many drivers to implement the kernel mode setting
50  * interfaces.
51  *
52  * Initialization is done as a four-step process with drm_fb_helper_prepare(),
53  * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and
54  * drm_fb_helper_initial_config(). Drivers with fancier requirements than the
55  * default behaviour can override the third step with their own code.
56  * Teardown is done with drm_fb_helper_fini().
57  *
58  * At runtime drivers should restore the fbdev console by calling
59  * drm_fb_helper_restore_fbdev_mode_unlocked() from their ->lastclose callback.
60  * They should also notify the fb helper code from updates to the output
61  * configuration by calling drm_fb_helper_hotplug_event(). For easier
62  * integration with the output polling code in drm_crtc_helper.c the modeset
63  * code provides a ->output_poll_changed callback.
64  *
65  * All other functions exported by the fb helper library can be used to
66  * implement the fbdev driver interface by the driver.
67  *
68  * It is possible, though perhaps somewhat tricky, to implement race-free
69  * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
70  * helper must be called first to initialize the minimum required to make
71  * hotplug detection work. Drivers also need to make sure to properly set up
72  * the dev->mode_config.funcs member. After calling drm_kms_helper_poll_init()
73  * it is safe to enable interrupts and start processing hotplug events. At the
74  * same time, drivers should initialize all modeset objects such as CRTCs,
75  * encoders and connectors. To finish up the fbdev helper initialization, the
76  * drm_fb_helper_init() function is called. To probe for all attached displays
77  * and set up an initial configuration using the detected hardware, drivers
78  * should call drm_fb_helper_single_add_all_connectors() followed by
79  * drm_fb_helper_initial_config().
80  */
81
82 /**
83  * drm_fb_helper_single_add_all_connectors() - add all connectors to fbdev
84  *                                             emulation helper
85  * @fb_helper: fbdev initialized with drm_fb_helper_init
86  *
87  * This functions adds all the available connectors for use with the given
88  * fb_helper. This is a separate step to allow drivers to freely assign
89  * connectors to the fbdev, e.g. if some are reserved for special purposes or
90  * not adequate to be used for the fbcon.
91  *
92  * This function is protected against concurrent connector hotadds/removals
93  * using drm_fb_helper_add_one_connector() and
94  * drm_fb_helper_remove_one_connector().
95  */
96 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
97 {
98         struct drm_device *dev = fb_helper->dev;
99         struct drm_connector *connector;
100         int i;
101
102         mutex_lock(&dev->mode_config.mutex);
103         drm_for_each_connector(connector, dev) {
104                 struct drm_fb_helper_connector *fb_helper_connector;
105
106                 fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
107                 if (!fb_helper_connector)
108                         goto fail;
109
110                 fb_helper_connector->connector = connector;
111                 fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
112         }
113         mutex_unlock(&dev->mode_config.mutex);
114         return 0;
115 fail:
116         for (i = 0; i < fb_helper->connector_count; i++) {
117                 kfree(fb_helper->connector_info[i]);
118                 fb_helper->connector_info[i] = NULL;
119         }
120         fb_helper->connector_count = 0;
121         mutex_unlock(&dev->mode_config.mutex);
122
123         return -ENOMEM;
124 }
125 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
126
127 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector)
128 {
129         struct drm_fb_helper_connector **temp;
130         struct drm_fb_helper_connector *fb_helper_connector;
131
132         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
133         if (fb_helper->connector_count + 1 > fb_helper->connector_info_alloc_count) {
134                 temp = krealloc(fb_helper->connector_info, sizeof(struct drm_fb_helper_connector *) * (fb_helper->connector_count + 1), GFP_KERNEL);
135                 if (!temp)
136                         return -ENOMEM;
137
138                 fb_helper->connector_info_alloc_count = fb_helper->connector_count + 1;
139                 fb_helper->connector_info = temp;
140         }
141
142
143         fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
144         if (!fb_helper_connector)
145                 return -ENOMEM;
146
147         fb_helper_connector->connector = connector;
148         fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
149         return 0;
150 }
151 EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
152
153 static void remove_from_modeset(struct drm_mode_set *set,
154                 struct drm_connector *connector)
155 {
156         int i, j;
157
158         for (i = 0; i < set->num_connectors; i++) {
159                 if (set->connectors[i] == connector)
160                         break;
161         }
162
163         if (i == set->num_connectors)
164                 return;
165
166         for (j = i + 1; j < set->num_connectors; j++) {
167                 set->connectors[j - 1] = set->connectors[j];
168         }
169         set->num_connectors--;
170
171         /*
172          * TODO maybe need to makes sure we set it back to !=NULL somewhere?
173          */
174         if (set->num_connectors == 0) {
175                 set->fb = NULL;
176                 drm_mode_destroy(connector->dev, set->mode);
177                 set->mode = NULL;
178         }
179 }
180
181 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
182                                        struct drm_connector *connector)
183 {
184         struct drm_fb_helper_connector *fb_helper_connector;
185         int i, j;
186
187         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
188
189         for (i = 0; i < fb_helper->connector_count; i++) {
190                 if (fb_helper->connector_info[i]->connector == connector)
191                         break;
192         }
193
194         if (i == fb_helper->connector_count)
195                 return -EINVAL;
196         fb_helper_connector = fb_helper->connector_info[i];
197
198         for (j = i + 1; j < fb_helper->connector_count; j++) {
199                 fb_helper->connector_info[j - 1] = fb_helper->connector_info[j];
200         }
201         fb_helper->connector_count--;
202         kfree(fb_helper_connector);
203
204         /* also cleanup dangling references to the connector: */
205         for (i = 0; i < fb_helper->crtc_count; i++)
206                 remove_from_modeset(&fb_helper->crtc_info[i].mode_set, connector);
207
208         return 0;
209 }
210 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
211
212 static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
213 {
214         uint16_t *r_base, *g_base, *b_base;
215         int i;
216
217         if (helper->funcs->gamma_get == NULL)
218                 return;
219
220         r_base = crtc->gamma_store;
221         g_base = r_base + crtc->gamma_size;
222         b_base = g_base + crtc->gamma_size;
223
224         for (i = 0; i < crtc->gamma_size; i++)
225                 helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
226 }
227
228 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
229 {
230         uint16_t *r_base, *g_base, *b_base;
231
232         if (crtc->funcs->gamma_set == NULL)
233                 return;
234
235         r_base = crtc->gamma_store;
236         g_base = r_base + crtc->gamma_size;
237         b_base = g_base + crtc->gamma_size;
238
239         crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
240 }
241
242 /**
243  * drm_fb_helper_debug_enter - implementation for ->fb_debug_enter
244  * @info: fbdev registered by the helper
245  */
246 int drm_fb_helper_debug_enter(struct fb_info *info)
247 {
248         struct drm_fb_helper *helper = info->par;
249         const struct drm_crtc_helper_funcs *funcs;
250         int i;
251
252         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
253                 for (i = 0; i < helper->crtc_count; i++) {
254                         struct drm_mode_set *mode_set =
255                                 &helper->crtc_info[i].mode_set;
256
257                         if (!mode_set->crtc->enabled)
258                                 continue;
259
260                         funcs = mode_set->crtc->helper_private;
261                         drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
262                         funcs->mode_set_base_atomic(mode_set->crtc,
263                                                     mode_set->fb,
264                                                     mode_set->x,
265                                                     mode_set->y,
266                                                     ENTER_ATOMIC_MODE_SET);
267                 }
268         }
269
270         return 0;
271 }
272 EXPORT_SYMBOL(drm_fb_helper_debug_enter);
273
274 /* Find the real fb for a given fb helper CRTC */
275 static struct drm_framebuffer *drm_mode_config_fb(struct drm_crtc *crtc)
276 {
277         struct drm_device *dev = crtc->dev;
278         struct drm_crtc *c;
279
280         drm_for_each_crtc(c, dev) {
281                 if (crtc->base.id == c->base.id)
282                         return c->primary->fb;
283         }
284
285         return NULL;
286 }
287
288 /**
289  * drm_fb_helper_debug_leave - implementation for ->fb_debug_leave
290  * @info: fbdev registered by the helper
291  */
292 int drm_fb_helper_debug_leave(struct fb_info *info)
293 {
294         struct drm_fb_helper *helper = info->par;
295         struct drm_crtc *crtc;
296         const struct drm_crtc_helper_funcs *funcs;
297         struct drm_framebuffer *fb;
298         int i;
299
300         for (i = 0; i < helper->crtc_count; i++) {
301                 struct drm_mode_set *mode_set = &helper->crtc_info[i].mode_set;
302                 crtc = mode_set->crtc;
303                 funcs = crtc->helper_private;
304                 fb = drm_mode_config_fb(crtc);
305
306                 if (!crtc->enabled)
307                         continue;
308
309                 if (!fb) {
310                         DRM_ERROR("no fb to restore??\n");
311                         continue;
312                 }
313
314                 drm_fb_helper_restore_lut_atomic(mode_set->crtc);
315                 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
316                                             crtc->y, LEAVE_ATOMIC_MODE_SET);
317         }
318
319         return 0;
320 }
321 EXPORT_SYMBOL(drm_fb_helper_debug_leave);
322
323 static bool restore_fbdev_mode(struct drm_fb_helper *fb_helper)
324 {
325         struct drm_device *dev = fb_helper->dev;
326         struct drm_plane *plane;
327         bool error = false;
328         int i;
329
330         drm_warn_on_modeset_not_all_locked(dev);
331
332         drm_for_each_plane(plane, dev) {
333                 if (plane->type != DRM_PLANE_TYPE_PRIMARY)
334                         drm_plane_force_disable(plane);
335
336                 if (dev->mode_config.rotation_property) {
337                         drm_mode_plane_set_obj_prop(plane,
338                                                     dev->mode_config.rotation_property,
339                                                     BIT(DRM_ROTATE_0));
340                 }
341         }
342
343         for (i = 0; i < fb_helper->crtc_count; i++) {
344                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
345                 struct drm_crtc *crtc = mode_set->crtc;
346                 int ret;
347
348                 if (crtc->funcs->cursor_set) {
349                         ret = crtc->funcs->cursor_set(crtc, NULL, 0, 0, 0);
350                         if (ret)
351                                 error = true;
352                 }
353
354                 ret = drm_mode_set_config_internal(mode_set);
355                 if (ret)
356                         error = true;
357         }
358         return error;
359 }
360
361 /**
362  * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
363  * @fb_helper: fbcon to restore
364  *
365  * This should be called from driver's drm ->lastclose callback
366  * when implementing an fbcon on top of kms using this helper. This ensures that
367  * the user isn't greeted with a black screen when e.g. X dies.
368  */
369 bool drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
370 {
371         struct drm_device *dev = fb_helper->dev;
372         bool ret;
373         bool do_delayed = false;
374
375         drm_modeset_lock_all(dev);
376         ret = restore_fbdev_mode(fb_helper);
377
378         do_delayed = fb_helper->delayed_hotplug;
379         if (do_delayed)
380                 fb_helper->delayed_hotplug = false;
381         drm_modeset_unlock_all(dev);
382
383         if (do_delayed)
384                 drm_fb_helper_hotplug_event(fb_helper);
385         return ret;
386 }
387 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
388
389 static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper)
390 {
391         struct drm_device *dev = fb_helper->dev;
392         struct drm_crtc *crtc;
393         int bound = 0, crtcs_bound = 0;
394
395         /* Sometimes user space wants everything disabled, so don't steal the
396          * display if there's a master. */
397         if (dev->primary->master)
398                 return false;
399
400         drm_for_each_crtc(crtc, dev) {
401                 if (crtc->primary->fb)
402                         crtcs_bound++;
403                 if (crtc->primary->fb == fb_helper->fb)
404                         bound++;
405         }
406
407         if (bound < crtcs_bound)
408                 return false;
409
410         return true;
411 }
412
413 #ifdef CONFIG_MAGIC_SYSRQ
414 /*
415  * restore fbcon display for all kms driver's using this helper, used for sysrq
416  * and panic handling.
417  */
418 static bool drm_fb_helper_force_kernel_mode(void)
419 {
420         bool ret, error = false;
421         struct drm_fb_helper *helper;
422
423         if (list_empty(&kernel_fb_helper_list))
424                 return false;
425
426         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
427                 struct drm_device *dev = helper->dev;
428
429                 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
430                         continue;
431
432                 drm_modeset_lock_all(dev);
433                 ret = restore_fbdev_mode(helper);
434                 if (ret)
435                         error = true;
436                 drm_modeset_unlock_all(dev);
437         }
438         return error;
439 }
440
441 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
442 {
443         bool ret;
444         ret = drm_fb_helper_force_kernel_mode();
445         if (ret == true)
446                 DRM_ERROR("Failed to restore crtc configuration\n");
447 }
448 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
449
450 static void drm_fb_helper_sysrq(int dummy1)
451 {
452         schedule_work(&drm_fb_helper_restore_work);
453 }
454
455 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
456         .handler = drm_fb_helper_sysrq,
457         .help_msg = "force-fb(V)",
458         .action_msg = "Restore framebuffer console",
459 };
460 #else
461 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
462 #endif
463
464 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
465 {
466         struct drm_fb_helper *fb_helper = info->par;
467         struct drm_device *dev = fb_helper->dev;
468         struct drm_crtc *crtc;
469         struct drm_connector *connector;
470         int i, j;
471
472         /*
473          * For each CRTC in this fb, turn the connectors on/off.
474          */
475         drm_modeset_lock_all(dev);
476         if (!drm_fb_helper_is_bound(fb_helper)) {
477                 drm_modeset_unlock_all(dev);
478                 return;
479         }
480
481         for (i = 0; i < fb_helper->crtc_count; i++) {
482                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
483
484                 if (!crtc->enabled)
485                         continue;
486
487                 /* Walk the connectors & encoders on this fb turning them on/off */
488                 for (j = 0; j < fb_helper->connector_count; j++) {
489                         connector = fb_helper->connector_info[j]->connector;
490                         connector->funcs->dpms(connector, dpms_mode);
491                         drm_object_property_set_value(&connector->base,
492                                 dev->mode_config.dpms_property, dpms_mode);
493                 }
494         }
495         drm_modeset_unlock_all(dev);
496 }
497
498 /**
499  * drm_fb_helper_blank - implementation for ->fb_blank
500  * @blank: desired blanking state
501  * @info: fbdev registered by the helper
502  */
503 int drm_fb_helper_blank(int blank, struct fb_info *info)
504 {
505         if (oops_in_progress)
506                 return -EBUSY;
507
508         switch (blank) {
509         /* Display: On; HSync: On, VSync: On */
510         case FB_BLANK_UNBLANK:
511                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
512                 break;
513         /* Display: Off; HSync: On, VSync: On */
514         case FB_BLANK_NORMAL:
515                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
516                 break;
517         /* Display: Off; HSync: Off, VSync: On */
518         case FB_BLANK_HSYNC_SUSPEND:
519                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
520                 break;
521         /* Display: Off; HSync: On, VSync: Off */
522         case FB_BLANK_VSYNC_SUSPEND:
523                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
524                 break;
525         /* Display: Off; HSync: Off, VSync: Off */
526         case FB_BLANK_POWERDOWN:
527                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
528                 break;
529         }
530         return 0;
531 }
532 EXPORT_SYMBOL(drm_fb_helper_blank);
533
534 static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper)
535 {
536         int i;
537
538         for (i = 0; i < helper->connector_count; i++)
539                 kfree(helper->connector_info[i]);
540         kfree(helper->connector_info);
541         for (i = 0; i < helper->crtc_count; i++) {
542                 kfree(helper->crtc_info[i].mode_set.connectors);
543                 if (helper->crtc_info[i].mode_set.mode)
544                         drm_mode_destroy(helper->dev, helper->crtc_info[i].mode_set.mode);
545         }
546         kfree(helper->crtc_info);
547 }
548
549 /**
550  * drm_fb_helper_prepare - setup a drm_fb_helper structure
551  * @dev: DRM device
552  * @helper: driver-allocated fbdev helper structure to set up
553  * @funcs: pointer to structure of functions associate with this helper
554  *
555  * Sets up the bare minimum to make the framebuffer helper usable. This is
556  * useful to implement race-free initialization of the polling helpers.
557  */
558 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
559                            const struct drm_fb_helper_funcs *funcs)
560 {
561         INIT_LIST_HEAD(&helper->kernel_fb_list);
562         helper->funcs = funcs;
563         helper->dev = dev;
564 }
565 EXPORT_SYMBOL(drm_fb_helper_prepare);
566
567 /**
568  * drm_fb_helper_init - initialize a drm_fb_helper structure
569  * @dev: drm device
570  * @fb_helper: driver-allocated fbdev helper structure to initialize
571  * @crtc_count: maximum number of crtcs to support in this fbdev emulation
572  * @max_conn_count: max connector count
573  *
574  * This allocates the structures for the fbdev helper with the given limits.
575  * Note that this won't yet touch the hardware (through the driver interfaces)
576  * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
577  * to allow driver writes more control over the exact init sequence.
578  *
579  * Drivers must call drm_fb_helper_prepare() before calling this function.
580  *
581  * RETURNS:
582  * Zero if everything went ok, nonzero otherwise.
583  */
584 int drm_fb_helper_init(struct drm_device *dev,
585                        struct drm_fb_helper *fb_helper,
586                        int crtc_count, int max_conn_count)
587 {
588         struct drm_crtc *crtc;
589         int i;
590
591         if (!max_conn_count)
592                 return -EINVAL;
593
594         fb_helper->crtc_info = kcalloc(crtc_count, sizeof(struct drm_fb_helper_crtc), GFP_KERNEL);
595         if (!fb_helper->crtc_info)
596                 return -ENOMEM;
597
598         fb_helper->crtc_count = crtc_count;
599         fb_helper->connector_info = kcalloc(dev->mode_config.num_connector, sizeof(struct drm_fb_helper_connector *), GFP_KERNEL);
600         if (!fb_helper->connector_info) {
601                 kfree(fb_helper->crtc_info);
602                 return -ENOMEM;
603         }
604         fb_helper->connector_info_alloc_count = dev->mode_config.num_connector;
605         fb_helper->connector_count = 0;
606
607         for (i = 0; i < crtc_count; i++) {
608                 fb_helper->crtc_info[i].mode_set.connectors =
609                         kcalloc(max_conn_count,
610                                 sizeof(struct drm_connector *),
611                                 GFP_KERNEL);
612
613                 if (!fb_helper->crtc_info[i].mode_set.connectors)
614                         goto out_free;
615                 fb_helper->crtc_info[i].mode_set.num_connectors = 0;
616         }
617
618         i = 0;
619         drm_for_each_crtc(crtc, dev) {
620                 fb_helper->crtc_info[i].mode_set.crtc = crtc;
621                 i++;
622         }
623
624         return 0;
625 out_free:
626         drm_fb_helper_crtc_free(fb_helper);
627         return -ENOMEM;
628 }
629 EXPORT_SYMBOL(drm_fb_helper_init);
630
631 /**
632  * drm_fb_helper_alloc_fbi - allocate fb_info and some of its members
633  * @fb_helper: driver-allocated fbdev helper
634  *
635  * A helper to alloc fb_info and the members cmap and apertures. Called
636  * by the driver within the fb_probe fb_helper callback function.
637  *
638  * RETURNS:
639  * fb_info pointer if things went okay, pointer containing error code
640  * otherwise
641  */
642 struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper)
643 {
644         struct device *dev = fb_helper->dev->dev;
645         struct fb_info *info;
646         int ret;
647
648         info = framebuffer_alloc(0, dev);
649         if (!info)
650                 return ERR_PTR(-ENOMEM);
651
652         ret = fb_alloc_cmap(&info->cmap, 256, 0);
653         if (ret)
654                 goto err_release;
655
656         info->apertures = alloc_apertures(1);
657         if (!info->apertures) {
658                 ret = -ENOMEM;
659                 goto err_free_cmap;
660         }
661
662         fb_helper->fbdev = info;
663
664         return info;
665
666 err_free_cmap:
667         fb_dealloc_cmap(&info->cmap);
668 err_release:
669         framebuffer_release(info);
670         return ERR_PTR(ret);
671 }
672 EXPORT_SYMBOL(drm_fb_helper_alloc_fbi);
673
674 /**
675  * drm_fb_helper_unregister_fbi - unregister fb_info framebuffer device
676  * @fb_helper: driver-allocated fbdev helper
677  *
678  * A wrapper around unregister_framebuffer, to release the fb_info
679  * framebuffer device
680  */
681 void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper)
682 {
683         if (fb_helper && fb_helper->fbdev)
684                 unregister_framebuffer(fb_helper->fbdev);
685 }
686 EXPORT_SYMBOL(drm_fb_helper_unregister_fbi);
687
688 /**
689  * drm_fb_helper_release_fbi - dealloc fb_info and its members
690  * @fb_helper: driver-allocated fbdev helper
691  *
692  * A helper to free memory taken by fb_info and the members cmap and
693  * apertures
694  */
695 void drm_fb_helper_release_fbi(struct drm_fb_helper *fb_helper)
696 {
697         if (fb_helper) {
698                 struct fb_info *info = fb_helper->fbdev;
699
700                 if (info) {
701                         if (info->cmap.len)
702                                 fb_dealloc_cmap(&info->cmap);
703                         framebuffer_release(info);
704                 }
705
706                 fb_helper->fbdev = NULL;
707         }
708 }
709 EXPORT_SYMBOL(drm_fb_helper_release_fbi);
710
711 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
712 {
713         if (!list_empty(&fb_helper->kernel_fb_list)) {
714                 list_del(&fb_helper->kernel_fb_list);
715                 if (list_empty(&kernel_fb_helper_list)) {
716                         unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
717                 }
718         }
719
720         drm_fb_helper_crtc_free(fb_helper);
721
722 }
723 EXPORT_SYMBOL(drm_fb_helper_fini);
724
725 /**
726  * drm_fb_helper_unlink_fbi - wrapper around unlink_framebuffer
727  * @fb_helper: driver-allocated fbdev helper
728  *
729  * A wrapper around unlink_framebuffer implemented by fbdev core
730  */
731 void drm_fb_helper_unlink_fbi(struct drm_fb_helper *fb_helper)
732 {
733         if (fb_helper && fb_helper->fbdev)
734                 unlink_framebuffer(fb_helper->fbdev);
735 }
736 EXPORT_SYMBOL(drm_fb_helper_unlink_fbi);
737
738 /**
739  * drm_fb_helper_sys_read - wrapper around fb_sys_read
740  * @info: fb_info struct pointer
741  * @buf: userspace buffer to read from framebuffer memory
742  * @count: number of bytes to read from framebuffer memory
743  * @ppos: read offset within framebuffer memory
744  *
745  * A wrapper around fb_sys_read implemented by fbdev core
746  */
747 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
748                                size_t count, loff_t *ppos)
749 {
750         return fb_sys_read(info, buf, count, ppos);
751 }
752 EXPORT_SYMBOL(drm_fb_helper_sys_read);
753
754 /**
755  * drm_fb_helper_sys_write - wrapper around fb_sys_write
756  * @info: fb_info struct pointer
757  * @buf: userspace buffer to write to framebuffer memory
758  * @count: number of bytes to write to framebuffer memory
759  * @ppos: write offset within framebuffer memory
760  *
761  * A wrapper around fb_sys_write implemented by fbdev core
762  */
763 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
764                                 size_t count, loff_t *ppos)
765 {
766         return fb_sys_write(info, buf, count, ppos);
767 }
768 EXPORT_SYMBOL(drm_fb_helper_sys_write);
769
770 /**
771  * drm_fb_helper_sys_fillrect - wrapper around sys_fillrect
772  * @info: fbdev registered by the helper
773  * @rect: info about rectangle to fill
774  *
775  * A wrapper around sys_fillrect implemented by fbdev core
776  */
777 void drm_fb_helper_sys_fillrect(struct fb_info *info,
778                                 const struct fb_fillrect *rect)
779 {
780         sys_fillrect(info, rect);
781 }
782 EXPORT_SYMBOL(drm_fb_helper_sys_fillrect);
783
784 /**
785  * drm_fb_helper_sys_copyarea - wrapper around sys_copyarea
786  * @info: fbdev registered by the helper
787  * @area: info about area to copy
788  *
789  * A wrapper around sys_copyarea implemented by fbdev core
790  */
791 void drm_fb_helper_sys_copyarea(struct fb_info *info,
792                                 const struct fb_copyarea *area)
793 {
794         sys_copyarea(info, area);
795 }
796 EXPORT_SYMBOL(drm_fb_helper_sys_copyarea);
797
798 /**
799  * drm_fb_helper_sys_imageblit - wrapper around sys_imageblit
800  * @info: fbdev registered by the helper
801  * @image: info about image to blit
802  *
803  * A wrapper around sys_imageblit implemented by fbdev core
804  */
805 void drm_fb_helper_sys_imageblit(struct fb_info *info,
806                                  const struct fb_image *image)
807 {
808         sys_imageblit(info, image);
809 }
810 EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
811
812 /**
813  * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect
814  * @info: fbdev registered by the helper
815  * @rect: info about rectangle to fill
816  *
817  * A wrapper around cfb_imageblit implemented by fbdev core
818  */
819 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
820                                 const struct fb_fillrect *rect)
821 {
822         cfb_fillrect(info, rect);
823 }
824 EXPORT_SYMBOL(drm_fb_helper_cfb_fillrect);
825
826 /**
827  * drm_fb_helper_cfb_copyarea - wrapper around cfb_copyarea
828  * @info: fbdev registered by the helper
829  * @area: info about area to copy
830  *
831  * A wrapper around cfb_copyarea implemented by fbdev core
832  */
833 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
834                                 const struct fb_copyarea *area)
835 {
836         cfb_copyarea(info, area);
837 }
838 EXPORT_SYMBOL(drm_fb_helper_cfb_copyarea);
839
840 /**
841  * drm_fb_helper_cfb_imageblit - wrapper around cfb_imageblit
842  * @info: fbdev registered by the helper
843  * @image: info about image to blit
844  *
845  * A wrapper around cfb_imageblit implemented by fbdev core
846  */
847 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
848                                  const struct fb_image *image)
849 {
850         cfb_imageblit(info, image);
851 }
852 EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit);
853
854 /**
855  * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
856  * @fb_helper: driver-allocated fbdev helper
857  * @state: desired state, zero to resume, non-zero to suspend
858  *
859  * A wrapper around fb_set_suspend implemented by fbdev core
860  */
861 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, int state)
862 {
863         if (fb_helper && fb_helper->fbdev)
864                 fb_set_suspend(fb_helper->fbdev, state);
865 }
866 EXPORT_SYMBOL(drm_fb_helper_set_suspend);
867
868 static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
869                      u16 blue, u16 regno, struct fb_info *info)
870 {
871         struct drm_fb_helper *fb_helper = info->par;
872         struct drm_framebuffer *fb = fb_helper->fb;
873         int pindex;
874
875         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
876                 u32 *palette;
877                 u32 value;
878                 /* place color in psuedopalette */
879                 if (regno > 16)
880                         return -EINVAL;
881                 palette = (u32 *)info->pseudo_palette;
882                 red >>= (16 - info->var.red.length);
883                 green >>= (16 - info->var.green.length);
884                 blue >>= (16 - info->var.blue.length);
885                 value = (red << info->var.red.offset) |
886                         (green << info->var.green.offset) |
887                         (blue << info->var.blue.offset);
888                 if (info->var.transp.length > 0) {
889                         u32 mask = (1 << info->var.transp.length) - 1;
890                         mask <<= info->var.transp.offset;
891                         value |= mask;
892                 }
893                 palette[regno] = value;
894                 return 0;
895         }
896
897         /*
898          * The driver really shouldn't advertise pseudo/directcolor
899          * visuals if it can't deal with the palette.
900          */
901         if (WARN_ON(!fb_helper->funcs->gamma_set ||
902                     !fb_helper->funcs->gamma_get))
903                 return -EINVAL;
904
905         pindex = regno;
906
907         if (fb->bits_per_pixel == 16) {
908                 pindex = regno << 3;
909
910                 if (fb->depth == 16 && regno > 63)
911                         return -EINVAL;
912                 if (fb->depth == 15 && regno > 31)
913                         return -EINVAL;
914
915                 if (fb->depth == 16) {
916                         u16 r, g, b;
917                         int i;
918                         if (regno < 32) {
919                                 for (i = 0; i < 8; i++)
920                                         fb_helper->funcs->gamma_set(crtc, red,
921                                                 green, blue, pindex + i);
922                         }
923
924                         fb_helper->funcs->gamma_get(crtc, &r,
925                                                     &g, &b,
926                                                     pindex >> 1);
927
928                         for (i = 0; i < 4; i++)
929                                 fb_helper->funcs->gamma_set(crtc, r,
930                                                             green, b,
931                                                             (pindex >> 1) + i);
932                 }
933         }
934
935         if (fb->depth != 16)
936                 fb_helper->funcs->gamma_set(crtc, red, green, blue, pindex);
937         return 0;
938 }
939
940 /**
941  * drm_fb_helper_setcmap - implementation for ->fb_setcmap
942  * @cmap: cmap to set
943  * @info: fbdev registered by the helper
944  */
945 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
946 {
947         struct drm_fb_helper *fb_helper = info->par;
948         struct drm_device *dev = fb_helper->dev;
949         const struct drm_crtc_helper_funcs *crtc_funcs;
950         u16 *red, *green, *blue, *transp;
951         struct drm_crtc *crtc;
952         int i, j, rc = 0;
953         int start;
954
955         if (oops_in_progress)
956                 return -EBUSY;
957
958         drm_modeset_lock_all(dev);
959         if (!drm_fb_helper_is_bound(fb_helper)) {
960                 drm_modeset_unlock_all(dev);
961                 return -EBUSY;
962         }
963
964         for (i = 0; i < fb_helper->crtc_count; i++) {
965                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
966                 crtc_funcs = crtc->helper_private;
967
968                 red = cmap->red;
969                 green = cmap->green;
970                 blue = cmap->blue;
971                 transp = cmap->transp;
972                 start = cmap->start;
973
974                 for (j = 0; j < cmap->len; j++) {
975                         u16 hred, hgreen, hblue, htransp = 0xffff;
976
977                         hred = *red++;
978                         hgreen = *green++;
979                         hblue = *blue++;
980
981                         if (transp)
982                                 htransp = *transp++;
983
984                         rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
985                         if (rc)
986                                 goto out;
987                 }
988                 if (crtc_funcs->load_lut)
989                         crtc_funcs->load_lut(crtc);
990         }
991  out:
992         drm_modeset_unlock_all(dev);
993         return rc;
994 }
995 EXPORT_SYMBOL(drm_fb_helper_setcmap);
996
997 /**
998  * drm_fb_helper_check_var - implementation for ->fb_check_var
999  * @var: screeninfo to check
1000  * @info: fbdev registered by the helper
1001  */
1002 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
1003                             struct fb_info *info)
1004 {
1005         struct drm_fb_helper *fb_helper = info->par;
1006         struct drm_framebuffer *fb = fb_helper->fb;
1007         int depth;
1008
1009         if (var->pixclock != 0 || in_dbg_master())
1010                 return -EINVAL;
1011
1012         /* Need to resize the fb object !!! */
1013         if (var->bits_per_pixel > fb->bits_per_pixel ||
1014             var->xres > fb->width || var->yres > fb->height ||
1015             var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
1016                 DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb "
1017                           "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1018                           var->xres, var->yres, var->bits_per_pixel,
1019                           var->xres_virtual, var->yres_virtual,
1020                           fb->width, fb->height, fb->bits_per_pixel);
1021                 return -EINVAL;
1022         }
1023
1024         switch (var->bits_per_pixel) {
1025         case 16:
1026                 depth = (var->green.length == 6) ? 16 : 15;
1027                 break;
1028         case 32:
1029                 depth = (var->transp.length > 0) ? 32 : 24;
1030                 break;
1031         default:
1032                 depth = var->bits_per_pixel;
1033                 break;
1034         }
1035
1036         switch (depth) {
1037         case 8:
1038                 var->red.offset = 0;
1039                 var->green.offset = 0;
1040                 var->blue.offset = 0;
1041                 var->red.length = 8;
1042                 var->green.length = 8;
1043                 var->blue.length = 8;
1044                 var->transp.length = 0;
1045                 var->transp.offset = 0;
1046                 break;
1047         case 15:
1048                 var->red.offset = 10;
1049                 var->green.offset = 5;
1050                 var->blue.offset = 0;
1051                 var->red.length = 5;
1052                 var->green.length = 5;
1053                 var->blue.length = 5;
1054                 var->transp.length = 1;
1055                 var->transp.offset = 15;
1056                 break;
1057         case 16:
1058                 var->red.offset = 11;
1059                 var->green.offset = 5;
1060                 var->blue.offset = 0;
1061                 var->red.length = 5;
1062                 var->green.length = 6;
1063                 var->blue.length = 5;
1064                 var->transp.length = 0;
1065                 var->transp.offset = 0;
1066                 break;
1067         case 24:
1068                 var->red.offset = 16;
1069                 var->green.offset = 8;
1070                 var->blue.offset = 0;
1071                 var->red.length = 8;
1072                 var->green.length = 8;
1073                 var->blue.length = 8;
1074                 var->transp.length = 0;
1075                 var->transp.offset = 0;
1076                 break;
1077         case 32:
1078                 var->red.offset = 16;
1079                 var->green.offset = 8;
1080                 var->blue.offset = 0;
1081                 var->red.length = 8;
1082                 var->green.length = 8;
1083                 var->blue.length = 8;
1084                 var->transp.length = 8;
1085                 var->transp.offset = 24;
1086                 break;
1087         default:
1088                 return -EINVAL;
1089         }
1090         return 0;
1091 }
1092 EXPORT_SYMBOL(drm_fb_helper_check_var);
1093
1094 /**
1095  * drm_fb_helper_set_par - implementation for ->fb_set_par
1096  * @info: fbdev registered by the helper
1097  *
1098  * This will let fbcon do the mode init and is called at initialization time by
1099  * the fbdev core when registering the driver, and later on through the hotplug
1100  * callback.
1101  */
1102 int drm_fb_helper_set_par(struct fb_info *info)
1103 {
1104         struct drm_fb_helper *fb_helper = info->par;
1105         struct fb_var_screeninfo *var = &info->var;
1106
1107         if (oops_in_progress)
1108                 return -EBUSY;
1109
1110         if (var->pixclock != 0) {
1111                 DRM_ERROR("PIXEL CLOCK SET\n");
1112                 return -EINVAL;
1113         }
1114
1115         drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
1116
1117         return 0;
1118 }
1119 EXPORT_SYMBOL(drm_fb_helper_set_par);
1120
1121 /**
1122  * drm_fb_helper_pan_display - implementation for ->fb_pan_display
1123  * @var: updated screen information
1124  * @info: fbdev registered by the helper
1125  */
1126 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
1127                               struct fb_info *info)
1128 {
1129         struct drm_fb_helper *fb_helper = info->par;
1130         struct drm_device *dev = fb_helper->dev;
1131         struct drm_mode_set *modeset;
1132         int ret = 0;
1133         int i;
1134
1135         if (oops_in_progress)
1136                 return -EBUSY;
1137
1138         drm_modeset_lock_all(dev);
1139         if (!drm_fb_helper_is_bound(fb_helper)) {
1140                 drm_modeset_unlock_all(dev);
1141                 return -EBUSY;
1142         }
1143
1144         for (i = 0; i < fb_helper->crtc_count; i++) {
1145                 modeset = &fb_helper->crtc_info[i].mode_set;
1146
1147                 modeset->x = var->xoffset;
1148                 modeset->y = var->yoffset;
1149
1150                 if (modeset->num_connectors) {
1151                         ret = drm_mode_set_config_internal(modeset);
1152                         if (!ret) {
1153                                 info->var.xoffset = var->xoffset;
1154                                 info->var.yoffset = var->yoffset;
1155                         }
1156                 }
1157         }
1158         drm_modeset_unlock_all(dev);
1159         return ret;
1160 }
1161 EXPORT_SYMBOL(drm_fb_helper_pan_display);
1162
1163 /*
1164  * Allocates the backing storage and sets up the fbdev info structure through
1165  * the ->fb_probe callback and then registers the fbdev and sets up the panic
1166  * notifier.
1167  */
1168 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
1169                                          int preferred_bpp)
1170 {
1171         int ret = 0;
1172         int crtc_count = 0;
1173         int i;
1174         struct fb_info *info;
1175         struct drm_fb_helper_surface_size sizes;
1176         int gamma_size = 0;
1177
1178         memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size));
1179         sizes.surface_depth = 24;
1180         sizes.surface_bpp = 32;
1181         sizes.fb_width = (unsigned)-1;
1182         sizes.fb_height = (unsigned)-1;
1183
1184         /* if driver picks 8 or 16 by default use that
1185            for both depth/bpp */
1186         if (preferred_bpp != sizes.surface_bpp)
1187                 sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
1188
1189         /* first up get a count of crtcs now in use and new min/maxes width/heights */
1190         for (i = 0; i < fb_helper->connector_count; i++) {
1191                 struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
1192                 struct drm_cmdline_mode *cmdline_mode;
1193
1194                 cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1195
1196                 if (cmdline_mode->bpp_specified) {
1197                         switch (cmdline_mode->bpp) {
1198                         case 8:
1199                                 sizes.surface_depth = sizes.surface_bpp = 8;
1200                                 break;
1201                         case 15:
1202                                 sizes.surface_depth = 15;
1203                                 sizes.surface_bpp = 16;
1204                                 break;
1205                         case 16:
1206                                 sizes.surface_depth = sizes.surface_bpp = 16;
1207                                 break;
1208                         case 24:
1209                                 sizes.surface_depth = sizes.surface_bpp = 24;
1210                                 break;
1211                         case 32:
1212                                 sizes.surface_depth = 24;
1213                                 sizes.surface_bpp = 32;
1214                                 break;
1215                         }
1216                         break;
1217                 }
1218         }
1219
1220         crtc_count = 0;
1221         for (i = 0; i < fb_helper->crtc_count; i++) {
1222                 struct drm_display_mode *desired_mode;
1223                 struct drm_mode_set *mode_set;
1224                 int x, y, j;
1225                 /* in case of tile group, are we the last tile vert or horiz?
1226                  * If no tile group you are always the last one both vertically
1227                  * and horizontally
1228                  */
1229                 bool lastv = true, lasth = true;
1230
1231                 desired_mode = fb_helper->crtc_info[i].desired_mode;
1232                 mode_set = &fb_helper->crtc_info[i].mode_set;
1233
1234                 if (!desired_mode)
1235                         continue;
1236
1237                 crtc_count++;
1238
1239                 x = fb_helper->crtc_info[i].x;
1240                 y = fb_helper->crtc_info[i].y;
1241
1242                 if (gamma_size == 0)
1243                         gamma_size = fb_helper->crtc_info[i].mode_set.crtc->gamma_size;
1244
1245                 sizes.surface_width  = max_t(u32, desired_mode->hdisplay + x, sizes.surface_width);
1246                 sizes.surface_height = max_t(u32, desired_mode->vdisplay + y, sizes.surface_height);
1247
1248                 for (j = 0; j < mode_set->num_connectors; j++) {
1249                         struct drm_connector *connector = mode_set->connectors[j];
1250                         if (connector->has_tile) {
1251                                 lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
1252                                 lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
1253                                 /* cloning to multiple tiles is just crazy-talk, so: */
1254                                 break;
1255                         }
1256                 }
1257
1258                 if (lasth)
1259                         sizes.fb_width  = min_t(u32, desired_mode->hdisplay + x, sizes.fb_width);
1260                 if (lastv)
1261                         sizes.fb_height = min_t(u32, desired_mode->vdisplay + y, sizes.fb_height);
1262         }
1263
1264         if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) {
1265                 /* hmm everyone went away - assume VGA cable just fell out
1266                    and will come back later. */
1267                 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1268                 sizes.fb_width = sizes.surface_width = 1024;
1269                 sizes.fb_height = sizes.surface_height = 768;
1270         }
1271
1272         /* push down into drivers */
1273         ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1274         if (ret < 0)
1275                 return ret;
1276
1277         info = fb_helper->fbdev;
1278
1279         /*
1280          * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1281          * events, but at init time drm_setup_crtcs needs to be called before
1282          * the fb is allocated (since we need to figure out the desired size of
1283          * the fb before we can allocate it ...). Hence we need to fix things up
1284          * here again.
1285          */
1286         for (i = 0; i < fb_helper->crtc_count; i++)
1287                 if (fb_helper->crtc_info[i].mode_set.num_connectors)
1288                         fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
1289
1290
1291         info->var.pixclock = 0;
1292         if (register_framebuffer(info) < 0)
1293                 return -EINVAL;
1294
1295         dev_info(fb_helper->dev->dev, "fb%d: %s frame buffer device\n",
1296                         info->node, info->fix.id);
1297
1298         if (list_empty(&kernel_fb_helper_list)) {
1299                 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
1300         }
1301
1302         list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
1303
1304         return 0;
1305 }
1306
1307 /**
1308  * drm_fb_helper_fill_fix - initializes fixed fbdev information
1309  * @info: fbdev registered by the helper
1310  * @pitch: desired pitch
1311  * @depth: desired depth
1312  *
1313  * Helper to fill in the fixed fbdev information useful for a non-accelerated
1314  * fbdev emulations. Drivers which support acceleration methods which impose
1315  * additional constraints need to set up their own limits.
1316  *
1317  * Drivers should call this (or their equivalent setup code) from their
1318  * ->fb_probe callback.
1319  */
1320 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1321                             uint32_t depth)
1322 {
1323         info->fix.type = FB_TYPE_PACKED_PIXELS;
1324         info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
1325                 FB_VISUAL_TRUECOLOR;
1326         info->fix.mmio_start = 0;
1327         info->fix.mmio_len = 0;
1328         info->fix.type_aux = 0;
1329         info->fix.xpanstep = 1; /* doing it in hw */
1330         info->fix.ypanstep = 1; /* doing it in hw */
1331         info->fix.ywrapstep = 0;
1332         info->fix.accel = FB_ACCEL_NONE;
1333
1334         info->fix.line_length = pitch;
1335         return;
1336 }
1337 EXPORT_SYMBOL(drm_fb_helper_fill_fix);
1338
1339 /**
1340  * drm_fb_helper_fill_var - initalizes variable fbdev information
1341  * @info: fbdev instance to set up
1342  * @fb_helper: fb helper instance to use as template
1343  * @fb_width: desired fb width
1344  * @fb_height: desired fb height
1345  *
1346  * Sets up the variable fbdev metainformation from the given fb helper instance
1347  * and the drm framebuffer allocated in fb_helper->fb.
1348  *
1349  * Drivers should call this (or their equivalent setup code) from their
1350  * ->fb_probe callback after having allocated the fbdev backing
1351  * storage framebuffer.
1352  */
1353 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
1354                             uint32_t fb_width, uint32_t fb_height)
1355 {
1356         struct drm_framebuffer *fb = fb_helper->fb;
1357         info->pseudo_palette = fb_helper->pseudo_palette;
1358         info->var.xres_virtual = fb->width;
1359         info->var.yres_virtual = fb->height;
1360         info->var.bits_per_pixel = fb->bits_per_pixel;
1361         info->var.accel_flags = FB_ACCELF_TEXT;
1362         info->var.xoffset = 0;
1363         info->var.yoffset = 0;
1364         info->var.activate = FB_ACTIVATE_NOW;
1365         info->var.height = -1;
1366         info->var.width = -1;
1367
1368         switch (fb->depth) {
1369         case 8:
1370                 info->var.red.offset = 0;
1371                 info->var.green.offset = 0;
1372                 info->var.blue.offset = 0;
1373                 info->var.red.length = 8; /* 8bit DAC */
1374                 info->var.green.length = 8;
1375                 info->var.blue.length = 8;
1376                 info->var.transp.offset = 0;
1377                 info->var.transp.length = 0;
1378                 break;
1379         case 15:
1380                 info->var.red.offset = 10;
1381                 info->var.green.offset = 5;
1382                 info->var.blue.offset = 0;
1383                 info->var.red.length = 5;
1384                 info->var.green.length = 5;
1385                 info->var.blue.length = 5;
1386                 info->var.transp.offset = 15;
1387                 info->var.transp.length = 1;
1388                 break;
1389         case 16:
1390                 info->var.red.offset = 11;
1391                 info->var.green.offset = 5;
1392                 info->var.blue.offset = 0;
1393                 info->var.red.length = 5;
1394                 info->var.green.length = 6;
1395                 info->var.blue.length = 5;
1396                 info->var.transp.offset = 0;
1397                 break;
1398         case 24:
1399                 info->var.red.offset = 16;
1400                 info->var.green.offset = 8;
1401                 info->var.blue.offset = 0;
1402                 info->var.red.length = 8;
1403                 info->var.green.length = 8;
1404                 info->var.blue.length = 8;
1405                 info->var.transp.offset = 0;
1406                 info->var.transp.length = 0;
1407                 break;
1408         case 32:
1409                 info->var.red.offset = 16;
1410                 info->var.green.offset = 8;
1411                 info->var.blue.offset = 0;
1412                 info->var.red.length = 8;
1413                 info->var.green.length = 8;
1414                 info->var.blue.length = 8;
1415                 info->var.transp.offset = 24;
1416                 info->var.transp.length = 8;
1417                 break;
1418         default:
1419                 break;
1420         }
1421
1422         info->var.xres = fb_width;
1423         info->var.yres = fb_height;
1424 }
1425 EXPORT_SYMBOL(drm_fb_helper_fill_var);
1426
1427 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
1428                                                uint32_t maxX,
1429                                                uint32_t maxY)
1430 {
1431         struct drm_connector *connector;
1432         int count = 0;
1433         int i;
1434
1435         for (i = 0; i < fb_helper->connector_count; i++) {
1436                 connector = fb_helper->connector_info[i]->connector;
1437                 count += connector->funcs->fill_modes(connector, maxX, maxY);
1438         }
1439
1440         return count;
1441 }
1442
1443 struct drm_display_mode *drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector, int width, int height)
1444 {
1445         struct drm_display_mode *mode;
1446
1447         list_for_each_entry(mode, &fb_connector->connector->modes, head) {
1448                 if (mode->hdisplay > width ||
1449                     mode->vdisplay > height)
1450                         continue;
1451                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
1452                         return mode;
1453         }
1454         return NULL;
1455 }
1456 EXPORT_SYMBOL(drm_has_preferred_mode);
1457
1458 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector *fb_connector)
1459 {
1460         return fb_connector->connector->cmdline_mode.specified;
1461 }
1462
1463 struct drm_display_mode *drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
1464                                                       int width, int height)
1465 {
1466         struct drm_cmdline_mode *cmdline_mode;
1467         struct drm_display_mode *mode;
1468         bool prefer_non_interlace;
1469
1470         cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1471         if (cmdline_mode->specified == false)
1472                 return NULL;
1473
1474         /* attempt to find a matching mode in the list of modes
1475          *  we have gotten so far, if not add a CVT mode that conforms
1476          */
1477         if (cmdline_mode->rb || cmdline_mode->margins)
1478                 goto create_mode;
1479
1480         prefer_non_interlace = !cmdline_mode->interlace;
1481 again:
1482         list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1483                 /* check width/height */
1484                 if (mode->hdisplay != cmdline_mode->xres ||
1485                     mode->vdisplay != cmdline_mode->yres)
1486                         continue;
1487
1488                 if (cmdline_mode->refresh_specified) {
1489                         if (mode->vrefresh != cmdline_mode->refresh)
1490                                 continue;
1491                 }
1492
1493                 if (cmdline_mode->interlace) {
1494                         if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
1495                                 continue;
1496                 } else if (prefer_non_interlace) {
1497                         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
1498                                 continue;
1499                 }
1500                 return mode;
1501         }
1502
1503         if (prefer_non_interlace) {
1504                 prefer_non_interlace = false;
1505                 goto again;
1506         }
1507
1508 create_mode:
1509         mode = drm_mode_create_from_cmdline_mode(fb_helper_conn->connector->dev,
1510                                                  cmdline_mode);
1511         list_add(&mode->head, &fb_helper_conn->connector->modes);
1512         return mode;
1513 }
1514 EXPORT_SYMBOL(drm_pick_cmdline_mode);
1515
1516 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
1517 {
1518         bool enable;
1519
1520         if (strict)
1521                 enable = connector->status == connector_status_connected;
1522         else
1523                 enable = connector->status != connector_status_disconnected;
1524
1525         return enable;
1526 }
1527
1528 static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
1529                                   bool *enabled)
1530 {
1531         bool any_enabled = false;
1532         struct drm_connector *connector;
1533         int i = 0;
1534
1535         for (i = 0; i < fb_helper->connector_count; i++) {
1536                 connector = fb_helper->connector_info[i]->connector;
1537                 enabled[i] = drm_connector_enabled(connector, true);
1538                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
1539                           enabled[i] ? "yes" : "no");
1540                 any_enabled |= enabled[i];
1541         }
1542
1543         if (any_enabled)
1544                 return;
1545
1546         for (i = 0; i < fb_helper->connector_count; i++) {
1547                 connector = fb_helper->connector_info[i]->connector;
1548                 enabled[i] = drm_connector_enabled(connector, false);
1549         }
1550 }
1551
1552 static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
1553                               struct drm_display_mode **modes,
1554                               struct drm_fb_offset *offsets,
1555                               bool *enabled, int width, int height)
1556 {
1557         int count, i, j;
1558         bool can_clone = false;
1559         struct drm_fb_helper_connector *fb_helper_conn;
1560         struct drm_display_mode *dmt_mode, *mode;
1561
1562         /* only contemplate cloning in the single crtc case */
1563         if (fb_helper->crtc_count > 1)
1564                 return false;
1565
1566         count = 0;
1567         for (i = 0; i < fb_helper->connector_count; i++) {
1568                 if (enabled[i])
1569                         count++;
1570         }
1571
1572         /* only contemplate cloning if more than one connector is enabled */
1573         if (count <= 1)
1574                 return false;
1575
1576         /* check the command line or if nothing common pick 1024x768 */
1577         can_clone = true;
1578         for (i = 0; i < fb_helper->connector_count; i++) {
1579                 if (!enabled[i])
1580                         continue;
1581                 fb_helper_conn = fb_helper->connector_info[i];
1582                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1583                 if (!modes[i]) {
1584                         can_clone = false;
1585                         break;
1586                 }
1587                 for (j = 0; j < i; j++) {
1588                         if (!enabled[j])
1589                                 continue;
1590                         if (!drm_mode_equal(modes[j], modes[i]))
1591                                 can_clone = false;
1592                 }
1593         }
1594
1595         if (can_clone) {
1596                 DRM_DEBUG_KMS("can clone using command line\n");
1597                 return true;
1598         }
1599
1600         /* try and find a 1024x768 mode on each connector */
1601         can_clone = true;
1602         dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
1603
1604         for (i = 0; i < fb_helper->connector_count; i++) {
1605
1606                 if (!enabled[i])
1607                         continue;
1608
1609                 fb_helper_conn = fb_helper->connector_info[i];
1610                 list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1611                         if (drm_mode_equal(mode, dmt_mode))
1612                                 modes[i] = mode;
1613                 }
1614                 if (!modes[i])
1615                         can_clone = false;
1616         }
1617
1618         if (can_clone) {
1619                 DRM_DEBUG_KMS("can clone using 1024x768\n");
1620                 return true;
1621         }
1622         DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1623         return false;
1624 }
1625
1626 static int drm_get_tile_offsets(struct drm_fb_helper *fb_helper,
1627                                 struct drm_display_mode **modes,
1628                                 struct drm_fb_offset *offsets,
1629                                 int idx,
1630                                 int h_idx, int v_idx)
1631 {
1632         struct drm_fb_helper_connector *fb_helper_conn;
1633         int i;
1634         int hoffset = 0, voffset = 0;
1635
1636         for (i = 0; i < fb_helper->connector_count; i++) {
1637                 fb_helper_conn = fb_helper->connector_info[i];
1638                 if (!fb_helper_conn->connector->has_tile)
1639                         continue;
1640
1641                 if (!modes[i] && (h_idx || v_idx)) {
1642                         DRM_DEBUG_KMS("no modes for connector tiled %d %d\n", i,
1643                                       fb_helper_conn->connector->base.id);
1644                         continue;
1645                 }
1646                 if (fb_helper_conn->connector->tile_h_loc < h_idx)
1647                         hoffset += modes[i]->hdisplay;
1648
1649                 if (fb_helper_conn->connector->tile_v_loc < v_idx)
1650                         voffset += modes[i]->vdisplay;
1651         }
1652         offsets[idx].x = hoffset;
1653         offsets[idx].y = voffset;
1654         DRM_DEBUG_KMS("returned %d %d for %d %d\n", hoffset, voffset, h_idx, v_idx);
1655         return 0;
1656 }
1657
1658 static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
1659                                  struct drm_display_mode **modes,
1660                                  struct drm_fb_offset *offsets,
1661                                  bool *enabled, int width, int height)
1662 {
1663         struct drm_fb_helper_connector *fb_helper_conn;
1664         int i;
1665         uint64_t conn_configured = 0, mask;
1666         int tile_pass = 0;
1667         mask = (1 << fb_helper->connector_count) - 1;
1668 retry:
1669         for (i = 0; i < fb_helper->connector_count; i++) {
1670                 fb_helper_conn = fb_helper->connector_info[i];
1671
1672                 if (conn_configured & (1 << i))
1673                         continue;
1674
1675                 if (enabled[i] == false) {
1676                         conn_configured |= (1 << i);
1677                         continue;
1678                 }
1679
1680                 /* first pass over all the untiled connectors */
1681                 if (tile_pass == 0 && fb_helper_conn->connector->has_tile)
1682                         continue;
1683
1684                 if (tile_pass == 1) {
1685                         if (fb_helper_conn->connector->tile_h_loc != 0 ||
1686                             fb_helper_conn->connector->tile_v_loc != 0)
1687                                 continue;
1688
1689                 } else {
1690                         if (fb_helper_conn->connector->tile_h_loc != tile_pass -1 &&
1691                             fb_helper_conn->connector->tile_v_loc != tile_pass - 1)
1692                         /* if this tile_pass doesn't cover any of the tiles - keep going */
1693                                 continue;
1694
1695                         /* find the tile offsets for this pass - need
1696                            to find all tiles left and above */
1697                         drm_get_tile_offsets(fb_helper, modes, offsets,
1698                                              i, fb_helper_conn->connector->tile_h_loc, fb_helper_conn->connector->tile_v_loc);
1699                 }
1700                 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1701                               fb_helper_conn->connector->base.id);
1702
1703                 /* got for command line mode first */
1704                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1705                 if (!modes[i]) {
1706                         DRM_DEBUG_KMS("looking for preferred mode on connector %d %d\n",
1707                                       fb_helper_conn->connector->base.id, fb_helper_conn->connector->tile_group ? fb_helper_conn->connector->tile_group->id : 0);
1708                         modes[i] = drm_has_preferred_mode(fb_helper_conn, width, height);
1709                 }
1710                 /* No preferred modes, pick one off the list */
1711                 if (!modes[i] && !list_empty(&fb_helper_conn->connector->modes)) {
1712                         list_for_each_entry(modes[i], &fb_helper_conn->connector->modes, head)
1713                                 break;
1714                 }
1715                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
1716                           "none");
1717                 conn_configured |= (1 << i);
1718         }
1719
1720         if ((conn_configured & mask) != mask) {
1721                 tile_pass++;
1722                 goto retry;
1723         }
1724         return true;
1725 }
1726
1727 static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
1728                           struct drm_fb_helper_crtc **best_crtcs,
1729                           struct drm_display_mode **modes,
1730                           int n, int width, int height)
1731 {
1732         int c, o;
1733         struct drm_device *dev = fb_helper->dev;
1734         struct drm_connector *connector;
1735         const struct drm_connector_helper_funcs *connector_funcs;
1736         struct drm_encoder *encoder;
1737         int my_score, best_score, score;
1738         struct drm_fb_helper_crtc **crtcs, *crtc;
1739         struct drm_fb_helper_connector *fb_helper_conn;
1740
1741         if (n == fb_helper->connector_count)
1742                 return 0;
1743
1744         fb_helper_conn = fb_helper->connector_info[n];
1745         connector = fb_helper_conn->connector;
1746
1747         best_crtcs[n] = NULL;
1748         best_score = drm_pick_crtcs(fb_helper, best_crtcs, modes, n+1, width, height);
1749         if (modes[n] == NULL)
1750                 return best_score;
1751
1752         crtcs = kzalloc(dev->mode_config.num_connector *
1753                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1754         if (!crtcs)
1755                 return best_score;
1756
1757         my_score = 1;
1758         if (connector->status == connector_status_connected)
1759                 my_score++;
1760         if (drm_has_cmdline_mode(fb_helper_conn))
1761                 my_score++;
1762         if (drm_has_preferred_mode(fb_helper_conn, width, height))
1763                 my_score++;
1764
1765         connector_funcs = connector->helper_private;
1766         encoder = connector_funcs->best_encoder(connector);
1767         if (!encoder)
1768                 goto out;
1769
1770         /* select a crtc for this connector and then attempt to configure
1771            remaining connectors */
1772         for (c = 0; c < fb_helper->crtc_count; c++) {
1773                 crtc = &fb_helper->crtc_info[c];
1774
1775                 if ((encoder->possible_crtcs & (1 << c)) == 0)
1776                         continue;
1777
1778                 for (o = 0; o < n; o++)
1779                         if (best_crtcs[o] == crtc)
1780                                 break;
1781
1782                 if (o < n) {
1783                         /* ignore cloning unless only a single crtc */
1784                         if (fb_helper->crtc_count > 1)
1785                                 continue;
1786
1787                         if (!drm_mode_equal(modes[o], modes[n]))
1788                                 continue;
1789                 }
1790
1791                 crtcs[n] = crtc;
1792                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_fb_helper_crtc *));
1793                 score = my_score + drm_pick_crtcs(fb_helper, crtcs, modes, n + 1,
1794                                                   width, height);
1795                 if (score > best_score) {
1796                         best_score = score;
1797                         memcpy(best_crtcs, crtcs,
1798                                dev->mode_config.num_connector *
1799                                sizeof(struct drm_fb_helper_crtc *));
1800                 }
1801         }
1802 out:
1803         kfree(crtcs);
1804         return best_score;
1805 }
1806
1807 static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
1808 {
1809         struct drm_device *dev = fb_helper->dev;
1810         struct drm_fb_helper_crtc **crtcs;
1811         struct drm_display_mode **modes;
1812         struct drm_fb_offset *offsets;
1813         struct drm_mode_set *modeset;
1814         bool *enabled;
1815         int width, height;
1816         int i;
1817
1818         DRM_DEBUG_KMS("\n");
1819
1820         width = dev->mode_config.max_width;
1821         height = dev->mode_config.max_height;
1822
1823         crtcs = kcalloc(dev->mode_config.num_connector,
1824                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1825         modes = kcalloc(dev->mode_config.num_connector,
1826                         sizeof(struct drm_display_mode *), GFP_KERNEL);
1827         offsets = kcalloc(dev->mode_config.num_connector,
1828                           sizeof(struct drm_fb_offset), GFP_KERNEL);
1829         enabled = kcalloc(dev->mode_config.num_connector,
1830                           sizeof(bool), GFP_KERNEL);
1831         if (!crtcs || !modes || !enabled || !offsets) {
1832                 DRM_ERROR("Memory allocation failed\n");
1833                 goto out;
1834         }
1835
1836
1837         drm_enable_connectors(fb_helper, enabled);
1838
1839         if (!(fb_helper->funcs->initial_config &&
1840               fb_helper->funcs->initial_config(fb_helper, crtcs, modes,
1841                                                offsets,
1842                                                enabled, width, height))) {
1843                 memset(modes, 0, dev->mode_config.num_connector*sizeof(modes[0]));
1844                 memset(crtcs, 0, dev->mode_config.num_connector*sizeof(crtcs[0]));
1845                 memset(offsets, 0, dev->mode_config.num_connector*sizeof(offsets[0]));
1846
1847                 if (!drm_target_cloned(fb_helper, modes, offsets,
1848                                        enabled, width, height) &&
1849                     !drm_target_preferred(fb_helper, modes, offsets,
1850                                           enabled, width, height))
1851                         DRM_ERROR("Unable to find initial modes\n");
1852
1853                 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
1854                               width, height);
1855
1856                 drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
1857         }
1858
1859         /* need to set the modesets up here for use later */
1860         /* fill out the connector<->crtc mappings into the modesets */
1861         for (i = 0; i < fb_helper->crtc_count; i++) {
1862                 modeset = &fb_helper->crtc_info[i].mode_set;
1863                 modeset->num_connectors = 0;
1864                 modeset->fb = NULL;
1865         }
1866
1867         for (i = 0; i < fb_helper->connector_count; i++) {
1868                 struct drm_display_mode *mode = modes[i];
1869                 struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
1870                 struct drm_fb_offset *offset = &offsets[i];
1871                 modeset = &fb_crtc->mode_set;
1872
1873                 if (mode && fb_crtc) {
1874                         DRM_DEBUG_KMS("desired mode %s set on crtc %d (%d,%d)\n",
1875                                       mode->name, fb_crtc->mode_set.crtc->base.id, offset->x, offset->y);
1876                         fb_crtc->desired_mode = mode;
1877                         fb_crtc->x = offset->x;
1878                         fb_crtc->y = offset->y;
1879                         if (modeset->mode)
1880                                 drm_mode_destroy(dev, modeset->mode);
1881                         modeset->mode = drm_mode_duplicate(dev,
1882                                                            fb_crtc->desired_mode);
1883                         modeset->connectors[modeset->num_connectors++] = fb_helper->connector_info[i]->connector;
1884                         modeset->fb = fb_helper->fb;
1885                         modeset->x = offset->x;
1886                         modeset->y = offset->y;
1887                 }
1888         }
1889
1890         /* Clear out any old modes if there are no more connected outputs. */
1891         for (i = 0; i < fb_helper->crtc_count; i++) {
1892                 modeset = &fb_helper->crtc_info[i].mode_set;
1893                 if (modeset->num_connectors == 0) {
1894                         BUG_ON(modeset->fb);
1895                         if (modeset->mode)
1896                                 drm_mode_destroy(dev, modeset->mode);
1897                         modeset->mode = NULL;
1898                 }
1899         }
1900 out:
1901         kfree(crtcs);
1902         kfree(modes);
1903         kfree(offsets);
1904         kfree(enabled);
1905 }
1906
1907 /**
1908  * drm_fb_helper_initial_config - setup a sane initial connector configuration
1909  * @fb_helper: fb_helper device struct
1910  * @bpp_sel: bpp value to use for the framebuffer configuration
1911  *
1912  * Scans the CRTCs and connectors and tries to put together an initial setup.
1913  * At the moment, this is a cloned configuration across all heads with
1914  * a new framebuffer object as the backing store.
1915  *
1916  * Note that this also registers the fbdev and so allows userspace to call into
1917  * the driver through the fbdev interfaces.
1918  *
1919  * This function will call down into the ->fb_probe callback to let
1920  * the driver allocate and initialize the fbdev info structure and the drm
1921  * framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
1922  * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
1923  * values for the fbdev info structure.
1924  *
1925  * RETURNS:
1926  * Zero if everything went ok, nonzero otherwise.
1927  */
1928 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
1929 {
1930         struct drm_device *dev = fb_helper->dev;
1931         int count = 0;
1932
1933         mutex_lock(&dev->mode_config.mutex);
1934         count = drm_fb_helper_probe_connector_modes(fb_helper,
1935                                                     dev->mode_config.max_width,
1936                                                     dev->mode_config.max_height);
1937         mutex_unlock(&dev->mode_config.mutex);
1938         /*
1939          * we shouldn't end up with no modes here.
1940          */
1941         if (count == 0)
1942                 dev_info(fb_helper->dev->dev, "No connectors reported connected with modes\n");
1943
1944         drm_setup_crtcs(fb_helper);
1945
1946         return drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
1947 }
1948 EXPORT_SYMBOL(drm_fb_helper_initial_config);
1949
1950 /**
1951  * drm_fb_helper_hotplug_event - respond to a hotplug notification by
1952  *                               probing all the outputs attached to the fb
1953  * @fb_helper: the drm_fb_helper
1954  *
1955  * Scan the connectors attached to the fb_helper and try to put together a
1956  * setup after *notification of a change in output configuration.
1957  *
1958  * Called at runtime, takes the mode config locks to be able to check/change the
1959  * modeset configuration. Must be run from process context (which usually means
1960  * either the output polling work or a work item launched from the driver's
1961  * hotplug interrupt).
1962  *
1963  * Note that drivers may call this even before calling
1964  * drm_fb_helper_initial_config but only aftert drm_fb_helper_init. This allows
1965  * for a race-free fbcon setup and will make sure that the fbdev emulation will
1966  * not miss any hotplug events.
1967  *
1968  * RETURNS:
1969  * 0 on success and a non-zero error code otherwise.
1970  */
1971 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
1972 {
1973         struct drm_device *dev = fb_helper->dev;
1974         u32 max_width, max_height;
1975
1976         mutex_lock(&fb_helper->dev->mode_config.mutex);
1977         if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
1978                 fb_helper->delayed_hotplug = true;
1979                 mutex_unlock(&fb_helper->dev->mode_config.mutex);
1980                 return 0;
1981         }
1982         DRM_DEBUG_KMS("\n");
1983
1984         max_width = fb_helper->fb->width;
1985         max_height = fb_helper->fb->height;
1986
1987         drm_fb_helper_probe_connector_modes(fb_helper, max_width, max_height);
1988         mutex_unlock(&fb_helper->dev->mode_config.mutex);
1989
1990         drm_modeset_lock_all(dev);
1991         drm_setup_crtcs(fb_helper);
1992         drm_modeset_unlock_all(dev);
1993         drm_fb_helper_set_par(fb_helper->fbdev);
1994
1995         return 0;
1996 }
1997 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
1998
1999 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
2000  * but the module doesn't depend on any fb console symbols.  At least
2001  * attempt to load fbcon to avoid leaving the system without a usable console.
2002  */
2003 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
2004 static int __init drm_fb_helper_modinit(void)
2005 {
2006         const char *name = "fbcon";
2007         struct module *fbcon;
2008
2009         mutex_lock(&module_mutex);
2010         fbcon = find_module(name);
2011         mutex_unlock(&module_mutex);
2012
2013         if (!fbcon)
2014                 request_module_nowait(name);
2015         return 0;
2016 }
2017
2018 module_init(drm_fb_helper_modinit);
2019 #endif