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[~andy/linux] / drivers / video / omap2 / dss / overlay.c
1 /*
2  * linux/drivers/video/omap2/dss/overlay.c
3  *
4  * Copyright (C) 2009 Nokia Corporation
5  * Author: Tomi Valkeinen <tomi.valkeinen@nokia.com>
6  *
7  * Some code and ideas taken from drivers/video/omap/ driver
8  * by Imre Deak.
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of the GNU General Public License version 2 as published by
12  * the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but WITHOUT
15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17  * more details.
18  *
19  * You should have received a copy of the GNU General Public License along with
20  * this program.  If not, see <http://www.gnu.org/licenses/>.
21  */
22
23 #define DSS_SUBSYS_NAME "OVERLAY"
24
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/err.h>
28 #include <linux/sysfs.h>
29 #include <linux/kobject.h>
30 #include <linux/platform_device.h>
31 #include <linux/delay.h>
32 #include <linux/slab.h>
33
34 #include <video/omapdss.h>
35 #include <plat/cpu.h>
36
37 #include "dss.h"
38 #include "dss_features.h"
39
40 static int num_overlays;
41 static struct list_head overlay_list;
42
43 static ssize_t overlay_name_show(struct omap_overlay *ovl, char *buf)
44 {
45         return snprintf(buf, PAGE_SIZE, "%s\n", ovl->name);
46 }
47
48 static ssize_t overlay_manager_show(struct omap_overlay *ovl, char *buf)
49 {
50         return snprintf(buf, PAGE_SIZE, "%s\n",
51                         ovl->manager ? ovl->manager->name : "<none>");
52 }
53
54 static ssize_t overlay_manager_store(struct omap_overlay *ovl, const char *buf,
55                 size_t size)
56 {
57         int i, r;
58         struct omap_overlay_manager *mgr = NULL;
59         struct omap_overlay_manager *old_mgr;
60         int len = size;
61
62         if (buf[size-1] == '\n')
63                 --len;
64
65         if (len > 0) {
66                 for (i = 0; i < omap_dss_get_num_overlay_managers(); ++i) {
67                         mgr = omap_dss_get_overlay_manager(i);
68
69                         if (sysfs_streq(buf, mgr->name))
70                                 break;
71
72                         mgr = NULL;
73                 }
74         }
75
76         if (len > 0 && mgr == NULL)
77                 return -EINVAL;
78
79         if (mgr)
80                 DSSDBG("manager %s found\n", mgr->name);
81
82         if (mgr == ovl->manager)
83                 return size;
84
85         old_mgr = ovl->manager;
86
87         r = dispc_runtime_get();
88         if (r)
89                 return r;
90
91         /* detach old manager */
92         if (old_mgr) {
93                 r = ovl->unset_manager(ovl);
94                 if (r) {
95                         DSSERR("detach failed\n");
96                         goto err;
97                 }
98
99                 r = old_mgr->apply(old_mgr);
100                 if (r)
101                         goto err;
102         }
103
104         if (mgr) {
105                 r = ovl->set_manager(ovl, mgr);
106                 if (r) {
107                         DSSERR("Failed to attach overlay\n");
108                         goto err;
109                 }
110
111                 r = mgr->apply(mgr);
112                 if (r)
113                         goto err;
114         }
115
116         dispc_runtime_put();
117
118         return size;
119
120 err:
121         dispc_runtime_put();
122         return r;
123 }
124
125 static ssize_t overlay_input_size_show(struct omap_overlay *ovl, char *buf)
126 {
127         return snprintf(buf, PAGE_SIZE, "%d,%d\n",
128                         ovl->info.width, ovl->info.height);
129 }
130
131 static ssize_t overlay_screen_width_show(struct omap_overlay *ovl, char *buf)
132 {
133         return snprintf(buf, PAGE_SIZE, "%d\n", ovl->info.screen_width);
134 }
135
136 static ssize_t overlay_position_show(struct omap_overlay *ovl, char *buf)
137 {
138         return snprintf(buf, PAGE_SIZE, "%d,%d\n",
139                         ovl->info.pos_x, ovl->info.pos_y);
140 }
141
142 static ssize_t overlay_position_store(struct omap_overlay *ovl,
143                 const char *buf, size_t size)
144 {
145         int r;
146         char *last;
147         struct omap_overlay_info info;
148
149         ovl->get_overlay_info(ovl, &info);
150
151         info.pos_x = simple_strtoul(buf, &last, 10);
152         ++last;
153         if (last - buf >= size)
154                 return -EINVAL;
155
156         info.pos_y = simple_strtoul(last, &last, 10);
157
158         r = ovl->set_overlay_info(ovl, &info);
159         if (r)
160                 return r;
161
162         if (ovl->manager) {
163                 r = ovl->manager->apply(ovl->manager);
164                 if (r)
165                         return r;
166         }
167
168         return size;
169 }
170
171 static ssize_t overlay_output_size_show(struct omap_overlay *ovl, char *buf)
172 {
173         return snprintf(buf, PAGE_SIZE, "%d,%d\n",
174                         ovl->info.out_width, ovl->info.out_height);
175 }
176
177 static ssize_t overlay_output_size_store(struct omap_overlay *ovl,
178                 const char *buf, size_t size)
179 {
180         int r;
181         char *last;
182         struct omap_overlay_info info;
183
184         ovl->get_overlay_info(ovl, &info);
185
186         info.out_width = simple_strtoul(buf, &last, 10);
187         ++last;
188         if (last - buf >= size)
189                 return -EINVAL;
190
191         info.out_height = simple_strtoul(last, &last, 10);
192
193         r = ovl->set_overlay_info(ovl, &info);
194         if (r)
195                 return r;
196
197         if (ovl->manager) {
198                 r = ovl->manager->apply(ovl->manager);
199                 if (r)
200                         return r;
201         }
202
203         return size;
204 }
205
206 static ssize_t overlay_enabled_show(struct omap_overlay *ovl, char *buf)
207 {
208         return snprintf(buf, PAGE_SIZE, "%d\n", ovl->info.enabled);
209 }
210
211 static ssize_t overlay_enabled_store(struct omap_overlay *ovl, const char *buf,
212                 size_t size)
213 {
214         int r, enable;
215         struct omap_overlay_info info;
216
217         ovl->get_overlay_info(ovl, &info);
218
219         r = kstrtoint(buf, 0, &enable);
220         if (r)
221                 return r;
222
223         info.enabled = !!enable;
224
225         r = ovl->set_overlay_info(ovl, &info);
226         if (r)
227                 return r;
228
229         if (ovl->manager) {
230                 r = ovl->manager->apply(ovl->manager);
231                 if (r)
232                         return r;
233         }
234
235         return size;
236 }
237
238 static ssize_t overlay_global_alpha_show(struct omap_overlay *ovl, char *buf)
239 {
240         return snprintf(buf, PAGE_SIZE, "%d\n",
241                         ovl->info.global_alpha);
242 }
243
244 static ssize_t overlay_global_alpha_store(struct omap_overlay *ovl,
245                 const char *buf, size_t size)
246 {
247         int r;
248         u8 alpha;
249         struct omap_overlay_info info;
250
251         if (!dss_has_feature(FEAT_GLOBAL_ALPHA))
252                 return -ENODEV;
253
254         r = kstrtou8(buf, 0, &alpha);
255         if (r)
256                 return r;
257
258         ovl->get_overlay_info(ovl, &info);
259
260         /* Video1 plane does not support global alpha
261          * to always make it 255 completely opaque
262          */
263         if (!dss_has_feature(FEAT_GLOBAL_ALPHA_VID1) &&
264                         ovl->id == OMAP_DSS_VIDEO1)
265                 info.global_alpha = 255;
266         else
267                 info.global_alpha = alpha;
268
269         r = ovl->set_overlay_info(ovl, &info);
270         if (r)
271                 return r;
272
273         if (ovl->manager) {
274                 r = ovl->manager->apply(ovl->manager);
275                 if (r)
276                         return r;
277         }
278
279         return size;
280 }
281
282 static ssize_t overlay_pre_mult_alpha_show(struct omap_overlay *ovl,
283                 char *buf)
284 {
285         return snprintf(buf, PAGE_SIZE, "%d\n",
286                         ovl->info.pre_mult_alpha);
287 }
288
289 static ssize_t overlay_pre_mult_alpha_store(struct omap_overlay *ovl,
290                 const char *buf, size_t size)
291 {
292         int r;
293         u8 alpha;
294         struct omap_overlay_info info;
295
296         r = kstrtou8(buf, 0, &alpha);
297         if (r)
298                 return r;
299
300         ovl->get_overlay_info(ovl, &info);
301
302         /* only GFX and Video2 plane support pre alpha multiplied
303          * set zero for Video1 plane
304          */
305         if (!dss_has_feature(FEAT_GLOBAL_ALPHA_VID1) &&
306                 ovl->id == OMAP_DSS_VIDEO1)
307                 info.pre_mult_alpha = 0;
308         else
309                 info.pre_mult_alpha = alpha;
310
311         r = ovl->set_overlay_info(ovl, &info);
312         if (r)
313                 return r;
314
315         if (ovl->manager) {
316                 r = ovl->manager->apply(ovl->manager);
317                 if (r)
318                         return r;
319         }
320
321         return size;
322 }
323
324 struct overlay_attribute {
325         struct attribute attr;
326         ssize_t (*show)(struct omap_overlay *, char *);
327         ssize_t (*store)(struct omap_overlay *, const char *, size_t);
328 };
329
330 #define OVERLAY_ATTR(_name, _mode, _show, _store) \
331         struct overlay_attribute overlay_attr_##_name = \
332         __ATTR(_name, _mode, _show, _store)
333
334 static OVERLAY_ATTR(name, S_IRUGO, overlay_name_show, NULL);
335 static OVERLAY_ATTR(manager, S_IRUGO|S_IWUSR,
336                 overlay_manager_show, overlay_manager_store);
337 static OVERLAY_ATTR(input_size, S_IRUGO, overlay_input_size_show, NULL);
338 static OVERLAY_ATTR(screen_width, S_IRUGO, overlay_screen_width_show, NULL);
339 static OVERLAY_ATTR(position, S_IRUGO|S_IWUSR,
340                 overlay_position_show, overlay_position_store);
341 static OVERLAY_ATTR(output_size, S_IRUGO|S_IWUSR,
342                 overlay_output_size_show, overlay_output_size_store);
343 static OVERLAY_ATTR(enabled, S_IRUGO|S_IWUSR,
344                 overlay_enabled_show, overlay_enabled_store);
345 static OVERLAY_ATTR(global_alpha, S_IRUGO|S_IWUSR,
346                 overlay_global_alpha_show, overlay_global_alpha_store);
347 static OVERLAY_ATTR(pre_mult_alpha, S_IRUGO|S_IWUSR,
348                 overlay_pre_mult_alpha_show,
349                 overlay_pre_mult_alpha_store);
350
351 static struct attribute *overlay_sysfs_attrs[] = {
352         &overlay_attr_name.attr,
353         &overlay_attr_manager.attr,
354         &overlay_attr_input_size.attr,
355         &overlay_attr_screen_width.attr,
356         &overlay_attr_position.attr,
357         &overlay_attr_output_size.attr,
358         &overlay_attr_enabled.attr,
359         &overlay_attr_global_alpha.attr,
360         &overlay_attr_pre_mult_alpha.attr,
361         NULL
362 };
363
364 static ssize_t overlay_attr_show(struct kobject *kobj, struct attribute *attr,
365                 char *buf)
366 {
367         struct omap_overlay *overlay;
368         struct overlay_attribute *overlay_attr;
369
370         overlay = container_of(kobj, struct omap_overlay, kobj);
371         overlay_attr = container_of(attr, struct overlay_attribute, attr);
372
373         if (!overlay_attr->show)
374                 return -ENOENT;
375
376         return overlay_attr->show(overlay, buf);
377 }
378
379 static ssize_t overlay_attr_store(struct kobject *kobj, struct attribute *attr,
380                 const char *buf, size_t size)
381 {
382         struct omap_overlay *overlay;
383         struct overlay_attribute *overlay_attr;
384
385         overlay = container_of(kobj, struct omap_overlay, kobj);
386         overlay_attr = container_of(attr, struct overlay_attribute, attr);
387
388         if (!overlay_attr->store)
389                 return -ENOENT;
390
391         return overlay_attr->store(overlay, buf, size);
392 }
393
394 static const struct sysfs_ops overlay_sysfs_ops = {
395         .show = overlay_attr_show,
396         .store = overlay_attr_store,
397 };
398
399 static struct kobj_type overlay_ktype = {
400         .sysfs_ops = &overlay_sysfs_ops,
401         .default_attrs = overlay_sysfs_attrs,
402 };
403
404 /* Check if overlay parameters are compatible with display */
405 int dss_check_overlay(struct omap_overlay *ovl, struct omap_dss_device *dssdev)
406 {
407         struct omap_overlay_info *info;
408         u16 outw, outh;
409         u16 dw, dh;
410
411         if (!dssdev)
412                 return 0;
413
414         if (!ovl->info.enabled)
415                 return 0;
416
417         info = &ovl->info;
418
419         if (info->paddr == 0) {
420                 DSSDBG("check_overlay failed: paddr 0\n");
421                 return -EINVAL;
422         }
423
424         dssdev->driver->get_resolution(dssdev, &dw, &dh);
425
426         DSSDBG("check_overlay %d: (%d,%d %dx%d -> %dx%d) disp (%dx%d)\n",
427                         ovl->id,
428                         info->pos_x, info->pos_y,
429                         info->width, info->height,
430                         info->out_width, info->out_height,
431                         dw, dh);
432
433         if ((ovl->caps & OMAP_DSS_OVL_CAP_SCALE) == 0) {
434                 outw = info->width;
435                 outh = info->height;
436         } else {
437                 if (info->out_width == 0)
438                         outw = info->width;
439                 else
440                         outw = info->out_width;
441
442                 if (info->out_height == 0)
443                         outh = info->height;
444                 else
445                         outh = info->out_height;
446         }
447
448         if (dw < info->pos_x + outw) {
449                 DSSDBG("check_overlay failed 1: %d < %d + %d\n",
450                                 dw, info->pos_x, outw);
451                 return -EINVAL;
452         }
453
454         if (dh < info->pos_y + outh) {
455                 DSSDBG("check_overlay failed 2: %d < %d + %d\n",
456                                 dh, info->pos_y, outh);
457                 return -EINVAL;
458         }
459
460         if ((ovl->supported_modes & info->color_mode) == 0) {
461                 DSSERR("overlay doesn't support mode %d\n", info->color_mode);
462                 return -EINVAL;
463         }
464
465         return 0;
466 }
467
468 static int dss_ovl_set_overlay_info(struct omap_overlay *ovl,
469                 struct omap_overlay_info *info)
470 {
471         int r;
472         struct omap_overlay_info old_info;
473
474         old_info = ovl->info;
475         ovl->info = *info;
476
477         if (ovl->manager) {
478                 r = dss_check_overlay(ovl, ovl->manager->device);
479                 if (r) {
480                         ovl->info = old_info;
481                         return r;
482                 }
483         }
484
485         ovl->info_dirty = true;
486
487         return 0;
488 }
489
490 static void dss_ovl_get_overlay_info(struct omap_overlay *ovl,
491                 struct omap_overlay_info *info)
492 {
493         *info = ovl->info;
494 }
495
496 static int dss_ovl_wait_for_go(struct omap_overlay *ovl)
497 {
498         return dss_mgr_wait_for_go_ovl(ovl);
499 }
500
501 static int omap_dss_set_manager(struct omap_overlay *ovl,
502                 struct omap_overlay_manager *mgr)
503 {
504         if (!mgr)
505                 return -EINVAL;
506
507         if (ovl->manager) {
508                 DSSERR("overlay '%s' already has a manager '%s'\n",
509                                 ovl->name, ovl->manager->name);
510                 return -EINVAL;
511         }
512
513         if (ovl->info.enabled) {
514                 DSSERR("overlay has to be disabled to change the manager\n");
515                 return -EINVAL;
516         }
517
518         ovl->manager = mgr;
519         ovl->manager_changed = true;
520
521         /* XXX: When there is an overlay on a DSI manual update display, and
522          * the overlay is first disabled, then moved to tv, and enabled, we
523          * seem to get SYNC_LOST_DIGIT error.
524          *
525          * Waiting doesn't seem to help, but updating the manual update display
526          * after disabling the overlay seems to fix this. This hints that the
527          * overlay is perhaps somehow tied to the LCD output until the output
528          * is updated.
529          *
530          * Userspace workaround for this is to update the LCD after disabling
531          * the overlay, but before moving the overlay to TV.
532          */
533
534         return 0;
535 }
536
537 static int omap_dss_unset_manager(struct omap_overlay *ovl)
538 {
539         if (!ovl->manager) {
540                 DSSERR("failed to detach overlay: manager not set\n");
541                 return -EINVAL;
542         }
543
544         if (ovl->info.enabled) {
545                 DSSERR("overlay has to be disabled to unset the manager\n");
546                 return -EINVAL;
547         }
548
549         ovl->manager = NULL;
550         ovl->manager_changed = true;
551
552         return 0;
553 }
554
555 int omap_dss_get_num_overlays(void)
556 {
557         return num_overlays;
558 }
559 EXPORT_SYMBOL(omap_dss_get_num_overlays);
560
561 struct omap_overlay *omap_dss_get_overlay(int num)
562 {
563         int i = 0;
564         struct omap_overlay *ovl;
565
566         list_for_each_entry(ovl, &overlay_list, list) {
567                 if (i++ == num)
568                         return ovl;
569         }
570
571         return NULL;
572 }
573 EXPORT_SYMBOL(omap_dss_get_overlay);
574
575 static void omap_dss_add_overlay(struct omap_overlay *overlay)
576 {
577         ++num_overlays;
578         list_add_tail(&overlay->list, &overlay_list);
579 }
580
581 static struct omap_overlay *dispc_overlays[MAX_DSS_OVERLAYS];
582
583 void dss_overlay_setup_dispc_manager(struct omap_overlay_manager *mgr)
584 {
585         mgr->num_overlays = dss_feat_get_num_ovls();
586         mgr->overlays = dispc_overlays;
587 }
588
589 #ifdef L4_EXAMPLE
590 static struct omap_overlay *l4_overlays[1];
591 void dss_overlay_setup_l4_manager(struct omap_overlay_manager *mgr)
592 {
593         mgr->num_overlays = 1;
594         mgr->overlays = l4_overlays;
595 }
596 #endif
597
598 void dss_init_overlays(struct platform_device *pdev)
599 {
600         int i, r;
601
602         INIT_LIST_HEAD(&overlay_list);
603
604         num_overlays = 0;
605
606         for (i = 0; i < dss_feat_get_num_ovls(); ++i) {
607                 struct omap_overlay *ovl;
608                 ovl = kzalloc(sizeof(*ovl), GFP_KERNEL);
609
610                 BUG_ON(ovl == NULL);
611
612                 switch (i) {
613                 case 0:
614                         ovl->name = "gfx";
615                         ovl->id = OMAP_DSS_GFX;
616                         ovl->caps = OMAP_DSS_OVL_CAP_DISPC;
617                         ovl->info.global_alpha = 255;
618                         break;
619                 case 1:
620                         ovl->name = "vid1";
621                         ovl->id = OMAP_DSS_VIDEO1;
622                         ovl->caps = OMAP_DSS_OVL_CAP_SCALE |
623                                 OMAP_DSS_OVL_CAP_DISPC;
624                         ovl->info.global_alpha = 255;
625                         break;
626                 case 2:
627                         ovl->name = "vid2";
628                         ovl->id = OMAP_DSS_VIDEO2;
629                         ovl->caps = OMAP_DSS_OVL_CAP_SCALE |
630                                 OMAP_DSS_OVL_CAP_DISPC;
631                         ovl->info.global_alpha = 255;
632                         break;
633                 }
634
635                 ovl->set_manager = &omap_dss_set_manager;
636                 ovl->unset_manager = &omap_dss_unset_manager;
637                 ovl->set_overlay_info = &dss_ovl_set_overlay_info;
638                 ovl->get_overlay_info = &dss_ovl_get_overlay_info;
639                 ovl->wait_for_go = &dss_ovl_wait_for_go;
640
641                 ovl->supported_modes =
642                         dss_feat_get_supported_color_modes(ovl->id);
643
644                 omap_dss_add_overlay(ovl);
645
646                 r = kobject_init_and_add(&ovl->kobj, &overlay_ktype,
647                                 &pdev->dev.kobj, "overlay%d", i);
648
649                 if (r) {
650                         DSSERR("failed to create sysfs file\n");
651                         continue;
652                 }
653
654                 dispc_overlays[i] = ovl;
655         }
656
657 #ifdef L4_EXAMPLE
658         {
659                 struct omap_overlay *ovl;
660                 ovl = kzalloc(sizeof(*ovl), GFP_KERNEL);
661
662                 BUG_ON(ovl == NULL);
663
664                 ovl->name = "l4";
665                 ovl->supported_modes = OMAP_DSS_COLOR_RGB24U;
666
667                 ovl->set_manager = &omap_dss_set_manager;
668                 ovl->unset_manager = &omap_dss_unset_manager;
669                 ovl->set_overlay_info = &dss_ovl_set_overlay_info;
670                 ovl->get_overlay_info = &dss_ovl_get_overlay_info;
671
672                 omap_dss_add_overlay(ovl);
673
674                 r = kobject_init_and_add(&ovl->kobj, &overlay_ktype,
675                                 &pdev->dev.kobj, "overlayl4");
676
677                 if (r)
678                         DSSERR("failed to create sysfs file\n");
679
680                 l4_overlays[0] = ovl;
681         }
682 #endif
683 }
684
685 /* connect overlays to the new device, if not already connected. if force
686  * selected, connect always. */
687 void dss_recheck_connections(struct omap_dss_device *dssdev, bool force)
688 {
689         int i;
690         struct omap_overlay_manager *lcd_mgr;
691         struct omap_overlay_manager *tv_mgr;
692         struct omap_overlay_manager *lcd2_mgr = NULL;
693         struct omap_overlay_manager *mgr = NULL;
694
695         lcd_mgr = omap_dss_get_overlay_manager(OMAP_DSS_OVL_MGR_LCD);
696         tv_mgr = omap_dss_get_overlay_manager(OMAP_DSS_OVL_MGR_TV);
697         if (dss_has_feature(FEAT_MGR_LCD2))
698                 lcd2_mgr = omap_dss_get_overlay_manager(OMAP_DSS_OVL_MGR_LCD2);
699
700         if (dssdev->channel == OMAP_DSS_CHANNEL_LCD2) {
701                 if (!lcd2_mgr->device || force) {
702                         if (lcd2_mgr->device)
703                                 lcd2_mgr->unset_device(lcd2_mgr);
704                         lcd2_mgr->set_device(lcd2_mgr, dssdev);
705                         mgr = lcd2_mgr;
706                 }
707         } else if (dssdev->type != OMAP_DISPLAY_TYPE_VENC
708                         && dssdev->type != OMAP_DISPLAY_TYPE_HDMI) {
709                 if (!lcd_mgr->device || force) {
710                         if (lcd_mgr->device)
711                                 lcd_mgr->unset_device(lcd_mgr);
712                         lcd_mgr->set_device(lcd_mgr, dssdev);
713                         mgr = lcd_mgr;
714                 }
715         }
716
717         if (dssdev->type == OMAP_DISPLAY_TYPE_VENC
718                         || dssdev->type == OMAP_DISPLAY_TYPE_HDMI) {
719                 if (!tv_mgr->device || force) {
720                         if (tv_mgr->device)
721                                 tv_mgr->unset_device(tv_mgr);
722                         tv_mgr->set_device(tv_mgr, dssdev);
723                         mgr = tv_mgr;
724                 }
725         }
726
727         if (mgr) {
728                 dispc_runtime_get();
729
730                 for (i = 0; i < dss_feat_get_num_ovls(); i++) {
731                         struct omap_overlay *ovl;
732                         ovl = omap_dss_get_overlay(i);
733                         if (!ovl->manager || force) {
734                                 if (ovl->manager)
735                                         omap_dss_unset_manager(ovl);
736                                 omap_dss_set_manager(ovl, mgr);
737                         }
738                 }
739
740                 dispc_runtime_put();
741         }
742 }
743
744 void dss_uninit_overlays(struct platform_device *pdev)
745 {
746         struct omap_overlay *ovl;
747
748         while (!list_empty(&overlay_list)) {
749                 ovl = list_first_entry(&overlay_list,
750                                 struct omap_overlay, list);
751                 list_del(&ovl->list);
752                 kobject_del(&ovl->kobj);
753                 kobject_put(&ovl->kobj);
754                 kfree(ovl);
755         }
756
757         num_overlays = 0;
758 }
759