GNU Linux-libre 4.14.302-gnu1
[releases.git] / drivers / gpu / drm / omapdrm / omap_crtc.c
1 /*
2  * drivers/gpu/drm/omapdrm/omap_crtc.c
3  *
4  * Copyright (C) 2011 Texas Instruments
5  * Author: Rob Clark <rob@ti.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License version 2 as published by
9  * the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19
20 #include <drm/drm_atomic.h>
21 #include <drm/drm_atomic_helper.h>
22 #include <drm/drm_crtc.h>
23 #include <drm/drm_crtc_helper.h>
24 #include <drm/drm_mode.h>
25 #include <drm/drm_plane_helper.h>
26
27 #include "omap_drv.h"
28
29 #define to_omap_crtc_state(x) container_of(x, struct omap_crtc_state, base)
30
31 struct omap_crtc_state {
32         /* Must be first. */
33         struct drm_crtc_state base;
34         /* Shadow values for legacy userspace support. */
35         unsigned int rotation;
36         unsigned int zpos;
37 };
38
39 #define to_omap_crtc(x) container_of(x, struct omap_crtc, base)
40
41 struct omap_crtc {
42         struct drm_crtc base;
43
44         const char *name;
45         enum omap_channel channel;
46
47         struct videomode vm;
48
49         bool ignore_digit_sync_lost;
50
51         bool enabled;
52         bool pending;
53         wait_queue_head_t pending_wait;
54         struct drm_pending_vblank_event *event;
55 };
56
57 /* -----------------------------------------------------------------------------
58  * Helper Functions
59  */
60
61 struct videomode *omap_crtc_timings(struct drm_crtc *crtc)
62 {
63         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
64         return &omap_crtc->vm;
65 }
66
67 enum omap_channel omap_crtc_channel(struct drm_crtc *crtc)
68 {
69         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
70         return omap_crtc->channel;
71 }
72
73 static bool omap_crtc_is_pending(struct drm_crtc *crtc)
74 {
75         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
76         unsigned long flags;
77         bool pending;
78
79         spin_lock_irqsave(&crtc->dev->event_lock, flags);
80         pending = omap_crtc->pending;
81         spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
82
83         return pending;
84 }
85
86 int omap_crtc_wait_pending(struct drm_crtc *crtc)
87 {
88         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
89
90         /*
91          * Timeout is set to a "sufficiently" high value, which should cover
92          * a single frame refresh even on slower displays.
93          */
94         return wait_event_timeout(omap_crtc->pending_wait,
95                                   !omap_crtc_is_pending(crtc),
96                                   msecs_to_jiffies(250));
97 }
98
99 /* -----------------------------------------------------------------------------
100  * DSS Manager Functions
101  */
102
103 /*
104  * Manager-ops, callbacks from output when they need to configure
105  * the upstream part of the video pipe.
106  *
107  * Most of these we can ignore until we add support for command-mode
108  * panels.. for video-mode the crtc-helpers already do an adequate
109  * job of sequencing the setup of the video pipe in the proper order
110  */
111
112 /* ovl-mgr-id -> crtc */
113 static struct omap_crtc *omap_crtcs[8];
114 static struct omap_dss_device *omap_crtc_output[8];
115
116 /* we can probably ignore these until we support command-mode panels: */
117 static int omap_crtc_dss_connect(enum omap_channel channel,
118                 struct omap_dss_device *dst)
119 {
120         const struct dispc_ops *dispc_ops = dispc_get_ops();
121
122         if (omap_crtc_output[channel])
123                 return -EINVAL;
124
125         if ((dispc_ops->mgr_get_supported_outputs(channel) & dst->id) == 0)
126                 return -EINVAL;
127
128         omap_crtc_output[channel] = dst;
129         dst->dispc_channel_connected = true;
130
131         return 0;
132 }
133
134 static void omap_crtc_dss_disconnect(enum omap_channel channel,
135                 struct omap_dss_device *dst)
136 {
137         omap_crtc_output[channel] = NULL;
138         dst->dispc_channel_connected = false;
139 }
140
141 static void omap_crtc_dss_start_update(enum omap_channel channel)
142 {
143 }
144
145 /* Called only from the encoder enable/disable and suspend/resume handlers. */
146 static void omap_crtc_set_enabled(struct drm_crtc *crtc, bool enable)
147 {
148         struct drm_device *dev = crtc->dev;
149         struct omap_drm_private *priv = dev->dev_private;
150         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
151         enum omap_channel channel = omap_crtc->channel;
152         struct omap_irq_wait *wait;
153         u32 framedone_irq, vsync_irq;
154         int ret;
155
156         if (WARN_ON(omap_crtc->enabled == enable))
157                 return;
158
159         if (omap_crtc_output[channel]->output_type == OMAP_DISPLAY_TYPE_HDMI) {
160                 priv->dispc_ops->mgr_enable(channel, enable);
161                 omap_crtc->enabled = enable;
162                 return;
163         }
164
165         if (omap_crtc->channel == OMAP_DSS_CHANNEL_DIGIT) {
166                 /*
167                  * Digit output produces some sync lost interrupts during the
168                  * first frame when enabling, so we need to ignore those.
169                  */
170                 omap_crtc->ignore_digit_sync_lost = true;
171         }
172
173         framedone_irq = priv->dispc_ops->mgr_get_framedone_irq(channel);
174         vsync_irq = priv->dispc_ops->mgr_get_vsync_irq(channel);
175
176         if (enable) {
177                 wait = omap_irq_wait_init(dev, vsync_irq, 1);
178         } else {
179                 /*
180                  * When we disable the digit output, we need to wait for
181                  * FRAMEDONE to know that DISPC has finished with the output.
182                  *
183                  * OMAP2/3 does not have FRAMEDONE irq for digit output, and in
184                  * that case we need to use vsync interrupt, and wait for both
185                  * even and odd frames.
186                  */
187
188                 if (framedone_irq)
189                         wait = omap_irq_wait_init(dev, framedone_irq, 1);
190                 else
191                         wait = omap_irq_wait_init(dev, vsync_irq, 2);
192         }
193
194         priv->dispc_ops->mgr_enable(channel, enable);
195         omap_crtc->enabled = enable;
196
197         ret = omap_irq_wait(dev, wait, msecs_to_jiffies(100));
198         if (ret) {
199                 dev_err(dev->dev, "%s: timeout waiting for %s\n",
200                                 omap_crtc->name, enable ? "enable" : "disable");
201         }
202
203         if (omap_crtc->channel == OMAP_DSS_CHANNEL_DIGIT) {
204                 omap_crtc->ignore_digit_sync_lost = false;
205                 /* make sure the irq handler sees the value above */
206                 mb();
207         }
208 }
209
210
211 static int omap_crtc_dss_enable(enum omap_channel channel)
212 {
213         struct omap_crtc *omap_crtc = omap_crtcs[channel];
214         struct omap_drm_private *priv = omap_crtc->base.dev->dev_private;
215
216         priv->dispc_ops->mgr_set_timings(omap_crtc->channel, &omap_crtc->vm);
217         omap_crtc_set_enabled(&omap_crtc->base, true);
218
219         return 0;
220 }
221
222 static void omap_crtc_dss_disable(enum omap_channel channel)
223 {
224         struct omap_crtc *omap_crtc = omap_crtcs[channel];
225
226         omap_crtc_set_enabled(&omap_crtc->base, false);
227 }
228
229 static void omap_crtc_dss_set_timings(enum omap_channel channel,
230                 const struct videomode *vm)
231 {
232         struct omap_crtc *omap_crtc = omap_crtcs[channel];
233         DBG("%s", omap_crtc->name);
234         omap_crtc->vm = *vm;
235 }
236
237 static void omap_crtc_dss_set_lcd_config(enum omap_channel channel,
238                 const struct dss_lcd_mgr_config *config)
239 {
240         struct omap_crtc *omap_crtc = omap_crtcs[channel];
241         struct omap_drm_private *priv = omap_crtc->base.dev->dev_private;
242
243         DBG("%s", omap_crtc->name);
244         priv->dispc_ops->mgr_set_lcd_config(omap_crtc->channel, config);
245 }
246
247 static int omap_crtc_dss_register_framedone(
248                 enum omap_channel channel,
249                 void (*handler)(void *), void *data)
250 {
251         return 0;
252 }
253
254 static void omap_crtc_dss_unregister_framedone(
255                 enum omap_channel channel,
256                 void (*handler)(void *), void *data)
257 {
258 }
259
260 static const struct dss_mgr_ops mgr_ops = {
261         .connect = omap_crtc_dss_connect,
262         .disconnect = omap_crtc_dss_disconnect,
263         .start_update = omap_crtc_dss_start_update,
264         .enable = omap_crtc_dss_enable,
265         .disable = omap_crtc_dss_disable,
266         .set_timings = omap_crtc_dss_set_timings,
267         .set_lcd_config = omap_crtc_dss_set_lcd_config,
268         .register_framedone_handler = omap_crtc_dss_register_framedone,
269         .unregister_framedone_handler = omap_crtc_dss_unregister_framedone,
270 };
271
272 /* -----------------------------------------------------------------------------
273  * Setup, Flush and Page Flip
274  */
275
276 void omap_crtc_error_irq(struct drm_crtc *crtc, uint32_t irqstatus)
277 {
278         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
279
280         if (omap_crtc->ignore_digit_sync_lost) {
281                 irqstatus &= ~DISPC_IRQ_SYNC_LOST_DIGIT;
282                 if (!irqstatus)
283                         return;
284         }
285
286         DRM_ERROR_RATELIMITED("%s: errors: %08x\n", omap_crtc->name, irqstatus);
287 }
288
289 void omap_crtc_vblank_irq(struct drm_crtc *crtc)
290 {
291         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
292         struct drm_device *dev = omap_crtc->base.dev;
293         struct omap_drm_private *priv = dev->dev_private;
294         bool pending;
295
296         spin_lock(&crtc->dev->event_lock);
297         /*
298          * If the dispc is busy we're racing the flush operation. Try again on
299          * the next vblank interrupt.
300          */
301         if (priv->dispc_ops->mgr_go_busy(omap_crtc->channel)) {
302                 spin_unlock(&crtc->dev->event_lock);
303                 return;
304         }
305
306         /* Send the vblank event if one has been requested. */
307         if (omap_crtc->event) {
308                 drm_crtc_send_vblank_event(crtc, omap_crtc->event);
309                 omap_crtc->event = NULL;
310         }
311
312         pending = omap_crtc->pending;
313         omap_crtc->pending = false;
314         spin_unlock(&crtc->dev->event_lock);
315
316         if (pending)
317                 drm_crtc_vblank_put(crtc);
318
319         /* Wake up omap_atomic_complete. */
320         wake_up(&omap_crtc->pending_wait);
321
322         DBG("%s: apply done", omap_crtc->name);
323 }
324
325 static void omap_crtc_write_crtc_properties(struct drm_crtc *crtc)
326 {
327         struct omap_drm_private *priv = crtc->dev->dev_private;
328         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
329         struct omap_overlay_manager_info info;
330
331         memset(&info, 0, sizeof(info));
332
333         info.default_color = 0x000000;
334         info.trans_enabled = false;
335         info.partial_alpha_enabled = false;
336         info.cpr_enable = false;
337
338         priv->dispc_ops->mgr_setup(omap_crtc->channel, &info);
339 }
340
341 /* -----------------------------------------------------------------------------
342  * CRTC Functions
343  */
344
345 static void omap_crtc_destroy(struct drm_crtc *crtc)
346 {
347         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
348
349         DBG("%s", omap_crtc->name);
350
351         drm_crtc_cleanup(crtc);
352
353         kfree(omap_crtc);
354 }
355
356 static void omap_crtc_arm_event(struct drm_crtc *crtc)
357 {
358         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
359
360         WARN_ON(omap_crtc->pending);
361         omap_crtc->pending = true;
362
363         if (crtc->state->event) {
364                 omap_crtc->event = crtc->state->event;
365                 crtc->state->event = NULL;
366         }
367 }
368
369 static void omap_crtc_atomic_enable(struct drm_crtc *crtc,
370                                     struct drm_crtc_state *old_state)
371 {
372         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
373         int ret;
374
375         DBG("%s", omap_crtc->name);
376
377         spin_lock_irq(&crtc->dev->event_lock);
378         drm_crtc_vblank_on(crtc);
379         ret = drm_crtc_vblank_get(crtc);
380         WARN_ON(ret != 0);
381
382         omap_crtc_arm_event(crtc);
383         spin_unlock_irq(&crtc->dev->event_lock);
384 }
385
386 static void omap_crtc_atomic_disable(struct drm_crtc *crtc,
387                                      struct drm_crtc_state *old_state)
388 {
389         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
390
391         DBG("%s", omap_crtc->name);
392
393         spin_lock_irq(&crtc->dev->event_lock);
394         if (crtc->state->event) {
395                 drm_crtc_send_vblank_event(crtc, crtc->state->event);
396                 crtc->state->event = NULL;
397         }
398         spin_unlock_irq(&crtc->dev->event_lock);
399
400         drm_crtc_vblank_off(crtc);
401 }
402
403 static void omap_crtc_mode_set_nofb(struct drm_crtc *crtc)
404 {
405         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
406         struct drm_display_mode *mode = &crtc->state->adjusted_mode;
407         struct omap_drm_private *priv = crtc->dev->dev_private;
408         const u32 flags_mask = DISPLAY_FLAGS_DE_HIGH | DISPLAY_FLAGS_DE_LOW |
409                 DISPLAY_FLAGS_PIXDATA_POSEDGE | DISPLAY_FLAGS_PIXDATA_NEGEDGE |
410                 DISPLAY_FLAGS_SYNC_POSEDGE | DISPLAY_FLAGS_SYNC_NEGEDGE;
411         unsigned int i;
412
413         DBG("%s: set mode: %d:\"%s\" %d %d %d %d %d %d %d %d %d %d 0x%x 0x%x",
414             omap_crtc->name, mode->base.id, mode->name,
415             mode->vrefresh, mode->clock,
416             mode->hdisplay, mode->hsync_start, mode->hsync_end, mode->htotal,
417             mode->vdisplay, mode->vsync_start, mode->vsync_end, mode->vtotal,
418             mode->type, mode->flags);
419
420         drm_display_mode_to_videomode(mode, &omap_crtc->vm);
421
422         /*
423          * HACK: This fixes the vm flags.
424          * struct drm_display_mode does not contain the VSYNC/HSYNC/DE flags
425          * and they get lost when converting back and forth between
426          * struct drm_display_mode and struct videomode. The hack below
427          * goes and fetches the missing flags from the panel drivers.
428          *
429          * Correct solution would be to use DRM's bus-flags, but that's not
430          * easily possible before the omapdrm's panel/encoder driver model
431          * has been changed to the DRM model.
432          */
433
434         for (i = 0; i < priv->num_encoders; ++i) {
435                 struct drm_encoder *encoder = priv->encoders[i];
436
437                 if (encoder->crtc == crtc) {
438                         struct omap_dss_device *dssdev;
439
440                         dssdev = omap_encoder_get_dssdev(encoder);
441
442                         if (dssdev) {
443                                 struct videomode vm = {0};
444
445                                 dssdev->driver->get_timings(dssdev, &vm);
446
447                                 omap_crtc->vm.flags |= vm.flags & flags_mask;
448                         }
449
450                         break;
451                 }
452         }
453 }
454
455 static int omap_crtc_atomic_check(struct drm_crtc *crtc,
456                                 struct drm_crtc_state *state)
457 {
458         struct drm_plane_state *pri_state;
459
460         if (state->color_mgmt_changed && state->gamma_lut) {
461                 uint length = state->gamma_lut->length /
462                         sizeof(struct drm_color_lut);
463
464                 if (length < 2)
465                         return -EINVAL;
466         }
467
468         pri_state = drm_atomic_get_new_plane_state(state->state, crtc->primary);
469         if (pri_state) {
470                 struct omap_crtc_state *omap_crtc_state =
471                         to_omap_crtc_state(state);
472
473                 /* Mirror new values for zpos and rotation in omap_crtc_state */
474                 omap_crtc_state->zpos = pri_state->zpos;
475                 omap_crtc_state->rotation = pri_state->rotation;
476         }
477
478         return 0;
479 }
480
481 static void omap_crtc_atomic_begin(struct drm_crtc *crtc,
482                                    struct drm_crtc_state *old_crtc_state)
483 {
484 }
485
486 static void omap_crtc_atomic_flush(struct drm_crtc *crtc,
487                                    struct drm_crtc_state *old_crtc_state)
488 {
489         struct omap_drm_private *priv = crtc->dev->dev_private;
490         struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
491         int ret;
492
493         if (crtc->state->color_mgmt_changed) {
494                 struct drm_color_lut *lut = NULL;
495                 uint length = 0;
496
497                 if (crtc->state->gamma_lut) {
498                         lut = (struct drm_color_lut *)
499                                 crtc->state->gamma_lut->data;
500                         length = crtc->state->gamma_lut->length /
501                                 sizeof(*lut);
502                 }
503                 priv->dispc_ops->mgr_set_gamma(omap_crtc->channel, lut, length);
504         }
505
506         omap_crtc_write_crtc_properties(crtc);
507
508         /* Only flush the CRTC if it is currently enabled. */
509         if (!omap_crtc->enabled)
510                 return;
511
512         DBG("%s: GO", omap_crtc->name);
513
514         ret = drm_crtc_vblank_get(crtc);
515         WARN_ON(ret != 0);
516
517         spin_lock_irq(&crtc->dev->event_lock);
518         priv->dispc_ops->mgr_go(omap_crtc->channel);
519         omap_crtc_arm_event(crtc);
520         spin_unlock_irq(&crtc->dev->event_lock);
521 }
522
523 static int omap_crtc_atomic_set_property(struct drm_crtc *crtc,
524                                          struct drm_crtc_state *state,
525                                          struct drm_property *property,
526                                          uint64_t val)
527 {
528         struct omap_drm_private *priv = crtc->dev->dev_private;
529         struct drm_plane_state *plane_state;
530
531         /*
532          * Delegate property set to the primary plane. Get the plane state and
533          * set the property directly, the shadow copy will be assigned in the
534          * omap_crtc_atomic_check callback. This way updates to plane state will
535          * always be mirrored in the crtc state correctly.
536          */
537         plane_state = drm_atomic_get_plane_state(state->state, crtc->primary);
538         if (IS_ERR(plane_state))
539                 return PTR_ERR(plane_state);
540
541         if (property == crtc->primary->rotation_property)
542                 plane_state->rotation = val;
543         else if (property == priv->zorder_prop)
544                 plane_state->zpos = val;
545         else
546                 return -EINVAL;
547
548         return 0;
549 }
550
551 static int omap_crtc_atomic_get_property(struct drm_crtc *crtc,
552                                          const struct drm_crtc_state *state,
553                                          struct drm_property *property,
554                                          uint64_t *val)
555 {
556         struct omap_drm_private *priv = crtc->dev->dev_private;
557         struct omap_crtc_state *omap_state = to_omap_crtc_state(state);
558
559         if (property == crtc->primary->rotation_property)
560                 *val = omap_state->rotation;
561         else if (property == priv->zorder_prop)
562                 *val = omap_state->zpos;
563         else
564                 return -EINVAL;
565
566         return 0;
567 }
568
569 static void omap_crtc_reset(struct drm_crtc *crtc)
570 {
571         if (crtc->state)
572                 __drm_atomic_helper_crtc_destroy_state(crtc->state);
573
574         kfree(crtc->state);
575         crtc->state = kzalloc(sizeof(struct omap_crtc_state), GFP_KERNEL);
576
577         if (crtc->state)
578                 crtc->state->crtc = crtc;
579 }
580
581 static struct drm_crtc_state *
582 omap_crtc_duplicate_state(struct drm_crtc *crtc)
583 {
584         struct omap_crtc_state *state, *current_state;
585
586         if (WARN_ON(!crtc->state))
587                 return NULL;
588
589         current_state = to_omap_crtc_state(crtc->state);
590
591         state = kmalloc(sizeof(*state), GFP_KERNEL);
592         if (!state)
593                 return NULL;
594
595         __drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);
596
597         state->zpos = current_state->zpos;
598         state->rotation = current_state->rotation;
599
600         return &state->base;
601 }
602
603 static const struct drm_crtc_funcs omap_crtc_funcs = {
604         .reset = omap_crtc_reset,
605         .set_config = drm_atomic_helper_set_config,
606         .destroy = omap_crtc_destroy,
607         .page_flip = drm_atomic_helper_page_flip,
608         .gamma_set = drm_atomic_helper_legacy_gamma_set,
609         .atomic_duplicate_state = omap_crtc_duplicate_state,
610         .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
611         .atomic_set_property = omap_crtc_atomic_set_property,
612         .atomic_get_property = omap_crtc_atomic_get_property,
613         .enable_vblank = omap_irq_enable_vblank,
614         .disable_vblank = omap_irq_disable_vblank,
615 };
616
617 static const struct drm_crtc_helper_funcs omap_crtc_helper_funcs = {
618         .mode_set_nofb = omap_crtc_mode_set_nofb,
619         .atomic_check = omap_crtc_atomic_check,
620         .atomic_begin = omap_crtc_atomic_begin,
621         .atomic_flush = omap_crtc_atomic_flush,
622         .atomic_enable = omap_crtc_atomic_enable,
623         .atomic_disable = omap_crtc_atomic_disable,
624 };
625
626 /* -----------------------------------------------------------------------------
627  * Init and Cleanup
628  */
629
630 static const char *channel_names[] = {
631         [OMAP_DSS_CHANNEL_LCD] = "lcd",
632         [OMAP_DSS_CHANNEL_DIGIT] = "tv",
633         [OMAP_DSS_CHANNEL_LCD2] = "lcd2",
634         [OMAP_DSS_CHANNEL_LCD3] = "lcd3",
635 };
636
637 void omap_crtc_pre_init(void)
638 {
639         memset(omap_crtcs, 0, sizeof(omap_crtcs));
640
641         dss_install_mgr_ops(&mgr_ops);
642 }
643
644 void omap_crtc_pre_uninit(void)
645 {
646         dss_uninstall_mgr_ops();
647 }
648
649 /* initialize crtc */
650 struct drm_crtc *omap_crtc_init(struct drm_device *dev,
651                 struct drm_plane *plane, struct omap_dss_device *dssdev)
652 {
653         struct omap_drm_private *priv = dev->dev_private;
654         struct drm_crtc *crtc = NULL;
655         struct omap_crtc *omap_crtc;
656         enum omap_channel channel;
657         struct omap_dss_device *out;
658         int ret;
659
660         out = omapdss_find_output_from_display(dssdev);
661         channel = out->dispc_channel;
662         omap_dss_put_device(out);
663
664         DBG("%s", channel_names[channel]);
665
666         /* Multiple displays on same channel is not allowed */
667         if (WARN_ON(omap_crtcs[channel] != NULL))
668                 return ERR_PTR(-EINVAL);
669
670         omap_crtc = kzalloc(sizeof(*omap_crtc), GFP_KERNEL);
671         if (!omap_crtc)
672                 return ERR_PTR(-ENOMEM);
673
674         crtc = &omap_crtc->base;
675
676         init_waitqueue_head(&omap_crtc->pending_wait);
677
678         omap_crtc->channel = channel;
679         omap_crtc->name = channel_names[channel];
680
681         ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL,
682                                         &omap_crtc_funcs, NULL);
683         if (ret < 0) {
684                 dev_err(dev->dev, "%s(): could not init crtc for: %s\n",
685                         __func__, dssdev->name);
686                 kfree(omap_crtc);
687                 return ERR_PTR(ret);
688         }
689
690         drm_crtc_helper_add(crtc, &omap_crtc_helper_funcs);
691
692         /* The dispc API adapts to what ever size, but the HW supports
693          * 256 element gamma table for LCDs and 1024 element table for
694          * OMAP_DSS_CHANNEL_DIGIT. X server assumes 256 element gamma
695          * tables so lets use that. Size of HW gamma table can be
696          * extracted with dispc_mgr_gamma_size(). If it returns 0
697          * gamma table is not supprted.
698          */
699         if (priv->dispc_ops->mgr_gamma_size(channel)) {
700                 uint gamma_lut_size = 256;
701
702                 drm_crtc_enable_color_mgmt(crtc, 0, false, gamma_lut_size);
703                 drm_mode_crtc_set_gamma_size(crtc, gamma_lut_size);
704         }
705
706         omap_plane_install_properties(crtc->primary, &crtc->base);
707
708         omap_crtcs[channel] = omap_crtc;
709
710         return crtc;
711 }