summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/drm_blend.c
blob: d02709dd2d4a38cb89f08f25912146cc9a7fca42 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
/*
 * Copyright (C) 2016 Samsung Electronics Co.Ltd
 * Authors:
 *	Marek Szyprowski <m.szyprowski@samsung.com>
 *
 * DRM core plane blending related functions
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 */

#include <linux/export.h>
#include <linux/slab.h>
#include <linux/sort.h>

#include <drm/drm_atomic.h>
#include <drm/drm_blend.h>
#include <drm/drm_device.h>
#include <drm/drm_print.h>

#include "drm_crtc_internal.h"

/**
 * DOC: overview
 *
 * The basic plane composition model supported by standard plane properties only
 * has a source rectangle (in logical pixels within the &drm_framebuffer), with
 * sub-pixel accuracy, which is scaled up to a pixel-aligned destination
 * rectangle in the visible area of a &drm_crtc. The visible area of a CRTC is
 * defined by the horizontal and vertical visible pixels (stored in @hdisplay
 * and @vdisplay) of the requested mode (stored in &drm_crtc_state.mode). These
 * two rectangles are both stored in the &drm_plane_state.
 *
 * For the atomic ioctl the following standard (atomic) properties on the plane object
 * encode the basic plane composition model:
 *
 * SRC_X:
 * 	X coordinate offset for the source rectangle within the
 * 	&drm_framebuffer, in 16.16 fixed point. Must be positive.
 * SRC_Y:
 * 	Y coordinate offset for the source rectangle within the
 * 	&drm_framebuffer, in 16.16 fixed point. Must be positive.
 * SRC_W:
 * 	Width for the source rectangle within the &drm_framebuffer, in 16.16
 * 	fixed point. SRC_X plus SRC_W must be within the width of the source
 * 	framebuffer. Must be positive.
 * SRC_H:
 * 	Height for the source rectangle within the &drm_framebuffer, in 16.16
 * 	fixed point. SRC_Y plus SRC_H must be within the height of the source
 * 	framebuffer. Must be positive.
 * CRTC_X:
 * 	X coordinate offset for the destination rectangle. Can be negative.
 * CRTC_Y:
 * 	Y coordinate offset for the destination rectangle. Can be negative.
 * CRTC_W:
 * 	Width for the destination rectangle. CRTC_X plus CRTC_W can extend past
 * 	the currently visible horizontal area of the &drm_crtc.
 * CRTC_H:
 * 	Height for the destination rectangle. CRTC_Y plus CRTC_H can extend past
 * 	the currently visible vertical area of the &drm_crtc.
 * FB_ID:
 * 	Mode object ID of the &drm_framebuffer this plane should scan out.
 * CRTC_ID:
 * 	Mode object ID of the &drm_crtc this plane should be connected to.
 *
 * Note that the source rectangle must fully lie within the bounds of the
 * &drm_framebuffer. The destination rectangle can lie outside of the visible
 * area of the current mode of the CRTC. It must be apprpriately clipped by the
 * driver, which can be done by calling drm_plane_helper_check_update(). Drivers
 * are also allowed to round the subpixel sampling positions appropriately, but
 * only to the next full pixel. No pixel outside of the source rectangle may
 * ever be sampled, which is important when applying more sophisticated
 * filtering than just a bilinear one when scaling. The filtering mode when
 * scaling is unspecified.
 *
 * On top of this basic transformation additional properties can be exposed by
 * the driver:
 *
 * alpha:
 * 	Alpha is setup with drm_plane_create_alpha_property(). It controls the
 * 	plane-wide opacity, from transparent (0) to opaque (0xffff). It can be
 * 	combined with pixel alpha.
 *	The pixel values in the framebuffers are expected to not be
 *	pre-multiplied by the global alpha associated to the plane.
 *
 * rotation:
 *	Rotation is set up with drm_plane_create_rotation_property(). It adds a
 *	rotation and reflection step between the source and destination rectangles.
 *	Without this property the rectangle is only scaled, but not rotated or
 *	reflected.
 *
 *	Possbile values:
 *
 *	"rotate-<degrees>":
 *		Signals that a drm plane is rotated <degrees> degrees in counter
 *		clockwise direction.
 *
 *	"reflect-<axis>":
 *		Signals that the contents of a drm plane is reflected along the
 *		<axis> axis, in the same way as mirroring.
 *
 *	reflect-x::
 *
 *			|o |    | o|
 *			|  | -> |  |
 *			| v|    |v |
 *
 *	reflect-y::
 *
 *			|o |    | ^|
 *			|  | -> |  |
 *			| v|    |o |
 *
 * zpos:
 *	Z position is set up with drm_plane_create_zpos_immutable_property() and
 *	drm_plane_create_zpos_property(). It controls the visibility of overlapping
 *	planes. Without this property the primary plane is always below the cursor
 *	plane, and ordering between all other planes is undefined. The positive
 *	Z axis points towards the user, i.e. planes with lower Z position values
 *	are underneath planes with higher Z position values. Note that the Z
 *	position value can also be immutable, to inform userspace about the
 *	hard-coded stacking of overlay planes, see
 *	drm_plane_create_zpos_immutable_property().
 *
 * pixel blend mode:
 *	Pixel blend mode is set up with drm_plane_create_blend_mode_property().
 *	It adds a blend mode for alpha blending equation selection, describing
 *	how the pixels from the current plane are composited with the
 *	background.
 *
 *	 Three alpha blending equations are defined:
 *
 *	 "None":
 *		 Blend formula that ignores the pixel alpha::
 *
 *			 out.rgb = plane_alpha * fg.rgb +
 *				 (1 - plane_alpha) * bg.rgb
 *
 *	 "Pre-multiplied":
 *		 Blend formula that assumes the pixel color values
 *		 have been already pre-multiplied with the alpha
 *		 channel values::
 *
 *			 out.rgb = plane_alpha * fg.rgb +
 *				 (1 - (plane_alpha * fg.alpha)) * bg.rgb
 *
 *	 "Coverage":
 *		 Blend formula that assumes the pixel color values have not
 *		 been pre-multiplied and will do so when blending them to the
 *		 background color values::
 *
 *			 out.rgb = plane_alpha * fg.alpha * fg.rgb +
 *				 (1 - (plane_alpha * fg.alpha)) * bg.rgb
 *
 *	 Using the following symbols:
 *
 *	 "fg.rgb":
 *		 Each of the RGB component values from the plane's pixel
 *	 "fg.alpha":
 *		 Alpha component value from the plane's pixel. If the plane's
 *		 pixel format has no alpha component, then this is assumed to be
 *		 1.0. In these cases, this property has no effect, as all three
 *		 equations become equivalent.
 *	 "bg.rgb":
 *		 Each of the RGB component values from the background
 *	 "plane_alpha":
 *		 Plane alpha value set by the plane "alpha" property. If the
 *		 plane does not expose the "alpha" property, then this is
 *		 assumed to be 1.0
 *
 * Note that all the property extensions described here apply either to the
 * plane or the CRTC (e.g. for the background color, which currently is not
 * exposed and assumed to be black).
 */

/**
 * drm_plane_create_alpha_property - create a new alpha property
 * @plane: drm plane
 *
 * This function creates a generic, mutable, alpha property and enables support
 * for it in the DRM core. It is attached to @plane.
 *
 * The alpha property will be allowed to be within the bounds of 0
 * (transparent) to 0xffff (opaque).
 *
 * Returns:
 * 0 on success, negative error code on failure.
 */
int drm_plane_create_alpha_property(struct drm_plane *plane)
{
	struct drm_property *prop;

	prop = drm_property_create_range(plane->dev, 0, "alpha",
					 0, DRM_BLEND_ALPHA_OPAQUE);
	if (!prop)
		return -ENOMEM;

	drm_object_attach_property(&plane->base, prop, DRM_BLEND_ALPHA_OPAQUE);
	plane->alpha_property = prop;

	if (plane->state)
		plane->state->alpha = DRM_BLEND_ALPHA_OPAQUE;

	return 0;
}
EXPORT_SYMBOL(drm_plane_create_alpha_property);

/**
 * drm_plane_create_rotation_property - create a new rotation property
 * @plane: drm plane
 * @rotation: initial value of the rotation property
 * @supported_rotations: bitmask of supported rotations and reflections
 *
 * This creates a new property with the selected support for transformations.
 *
 * Since a rotation by 180° degress is the same as reflecting both along the x
 * and the y axis the rotation property is somewhat redundant. Drivers can use
 * drm_rotation_simplify() to normalize values of this property.
 *
 * The property exposed to userspace is a bitmask property (see
 * drm_property_create_bitmask()) called "rotation" and has the following
 * bitmask enumaration values:
 *
 * DRM_MODE_ROTATE_0:
 * 	"rotate-0"
 * DRM_MODE_ROTATE_90:
 * 	"rotate-90"
 * DRM_MODE_ROTATE_180:
 * 	"rotate-180"
 * DRM_MODE_ROTATE_270:
 * 	"rotate-270"
 * DRM_MODE_REFLECT_X:
 * 	"reflect-x"
 * DRM_MODE_REFLECT_Y:
 * 	"reflect-y"
 *
 * Rotation is the specified amount in degrees in counter clockwise direction,
 * the X and Y axis are within the source rectangle, i.e.  the X/Y axis before
 * rotation. After reflection, the rotation is applied to the image sampled from
 * the source rectangle, before scaling it to fit the destination rectangle.
 */
int drm_plane_create_rotation_property(struct drm_plane *plane,
				       unsigned int rotation,
				       unsigned int supported_rotations)
{
	static const struct drm_prop_enum_list props[] = {
		{ __builtin_ffs(DRM_MODE_ROTATE_0) - 1,   "rotate-0" },
		{ __builtin_ffs(DRM_MODE_ROTATE_90) - 1,  "rotate-90" },
		{ __builtin_ffs(DRM_MODE_ROTATE_180) - 1, "rotate-180" },
		{ __builtin_ffs(DRM_MODE_ROTATE_270) - 1, "rotate-270" },
		{ __builtin_ffs(DRM_MODE_REFLECT_X) - 1,  "reflect-x" },
		{ __builtin_ffs(DRM_MODE_REFLECT_Y) - 1,  "reflect-y" },
	};
	struct drm_property *prop;

	WARN_ON((supported_rotations & DRM_MODE_ROTATE_MASK) == 0);
	WARN_ON(!is_power_of_2(rotation & DRM_MODE_ROTATE_MASK));
	WARN_ON(rotation & ~supported_rotations);

	prop = drm_property_create_bitmask(plane->dev, 0, "rotation",
					   props, ARRAY_SIZE(props),
					   supported_rotations);
	if (!prop)
		return -ENOMEM;

	drm_object_attach_property(&plane->base, prop, rotation);

	if (plane->state)
		plane->state->rotation = rotation;

	plane->rotation_property = prop;

	return 0;
}
EXPORT_SYMBOL(drm_plane_create_rotation_property);

/**
 * drm_rotation_simplify() - Try to simplify the rotation
 * @rotation: Rotation to be simplified
 * @supported_rotations: Supported rotations
 *
 * Attempt to simplify the rotation to a form that is supported.
 * Eg. if the hardware supports everything except DRM_MODE_REFLECT_X
 * one could call this function like this:
 *
 * drm_rotation_simplify(rotation, DRM_MODE_ROTATE_0 |
 *                       DRM_MODE_ROTATE_90 | DRM_MODE_ROTATE_180 |
 *                       DRM_MODE_ROTATE_270 | DRM_MODE_REFLECT_Y);
 *
 * to eliminate the DRM_MODE_ROTATE_X flag. Depending on what kind of
 * transforms the hardware supports, this function may not
 * be able to produce a supported transform, so the caller should
 * check the result afterwards.
 */
unsigned int drm_rotation_simplify(unsigned int rotation,
				   unsigned int supported_rotations)
{
	if (rotation & ~supported_rotations) {
		rotation ^= DRM_MODE_REFLECT_X | DRM_MODE_REFLECT_Y;
		rotation = (rotation & DRM_MODE_REFLECT_MASK) |
		           BIT((ffs(rotation & DRM_MODE_ROTATE_MASK) + 1)
		           % 4);
	}

	return rotation;
}
EXPORT_SYMBOL(drm_rotation_simplify);

/**
 * drm_plane_create_zpos_property - create mutable zpos property
 * @plane: drm plane
 * @zpos: initial value of zpos property
 * @min: minimal possible value of zpos property
 * @max: maximal possible value of zpos property
 *
 * This function initializes generic mutable zpos property and enables support
 * for it in drm core. Drivers can then attach this property to planes to enable
 * support for configurable planes arrangement during blending operation.
 * Drivers that attach a mutable zpos property to any plane should call the
 * drm_atomic_normalize_zpos() helper during their implementation of
 * &drm_mode_config_funcs.atomic_check(), which will update the normalized zpos
 * values and store them in &drm_plane_state.normalized_zpos. Usually min
 * should be set to 0 and max to maximal number of planes for given crtc - 1.
 *
 * If zpos of some planes cannot be changed (like fixed background or
 * cursor/topmost planes), driver should adjust min/max values and assign those
 * planes immutable zpos property with lower or higher values (for more
 * information, see drm_plane_create_zpos_immutable_property() function). In such
 * case driver should also assign proper initial zpos values for all planes in
 * its plane_reset() callback, so the planes will be always sorted properly.
 *
 * See also drm_atomic_normalize_zpos().
 *
 * The property exposed to userspace is called "zpos".
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_plane_create_zpos_property(struct drm_plane *plane,
				   unsigned int zpos,
				   unsigned int min, unsigned int max)
{
	struct drm_property *prop;

	prop = drm_property_create_range(plane->dev, 0, "zpos", min, max);
	if (!prop)
		return -ENOMEM;

	drm_object_attach_property(&plane->base, prop, zpos);

	plane->zpos_property = prop;

	if (plane->state) {
		plane->state->zpos = zpos;
		plane->state->normalized_zpos = zpos;
	}

	return 0;
}
EXPORT_SYMBOL(drm_plane_create_zpos_property);

/**
 * drm_plane_create_zpos_immutable_property - create immuttable zpos property
 * @plane: drm plane
 * @zpos: value of zpos property
 *
 * This function initializes generic immutable zpos property and enables
 * support for it in drm core. Using this property driver lets userspace
 * to get the arrangement of the planes for blending operation and notifies
 * it that the hardware (or driver) doesn't support changing of the planes'
 * order. For mutable zpos see drm_plane_create_zpos_property().
 *
 * The property exposed to userspace is called "zpos".
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_plane_create_zpos_immutable_property(struct drm_plane *plane,
					     unsigned int zpos)
{
	struct drm_property *prop;

	prop = drm_property_create_range(plane->dev, DRM_MODE_PROP_IMMUTABLE,
					 "zpos", zpos, zpos);
	if (!prop)
		return -ENOMEM;

	drm_object_attach_property(&plane->base, prop, zpos);

	plane->zpos_property = prop;

	if (plane->state) {
		plane->state->zpos = zpos;
		plane->state->normalized_zpos = zpos;
	}

	return 0;
}
EXPORT_SYMBOL(drm_plane_create_zpos_immutable_property);

static int drm_atomic_state_zpos_cmp(const void *a, const void *b)
{
	const struct drm_plane_state *sa = *(struct drm_plane_state **)a;
	const struct drm_plane_state *sb = *(struct drm_plane_state **)b;

	if (sa->zpos != sb->zpos)
		return sa->zpos - sb->zpos;
	else
		return sa->plane->base.id - sb->plane->base.id;
}

static int drm_atomic_helper_crtc_normalize_zpos(struct drm_crtc *crtc,
					  struct drm_crtc_state *crtc_state)
{
	struct drm_atomic_state *state = crtc_state->state;
	struct drm_device *dev = crtc->dev;
	int total_planes = dev->mode_config.num_total_plane;
	struct drm_plane_state **states;
	struct drm_plane *plane;
	int i, n = 0;
	int ret = 0;

	DRM_DEBUG_ATOMIC("[CRTC:%d:%s] calculating normalized zpos values\n",
			 crtc->base.id, crtc->name);

	states = kmalloc_array(total_planes, sizeof(*states), GFP_KERNEL);
	if (!states)
		return -ENOMEM;

	/*
	 * Normalization process might create new states for planes which
	 * normalized_zpos has to be recalculated.
	 */
	drm_for_each_plane_mask(plane, dev, crtc_state->plane_mask) {
		struct drm_plane_state *plane_state =
			drm_atomic_get_plane_state(state, plane);
		if (IS_ERR(plane_state)) {
			ret = PTR_ERR(plane_state);
			goto done;
		}
		states[n++] = plane_state;
		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] processing zpos value %d\n",
				 plane->base.id, plane->name,
				 plane_state->zpos);
	}

	sort(states, n, sizeof(*states), drm_atomic_state_zpos_cmp, NULL);

	for (i = 0; i < n; i++) {
		plane = states[i]->plane;

		states[i]->normalized_zpos = i;
		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] normalized zpos value %d\n",
				 plane->base.id, plane->name, i);
	}
	crtc_state->zpos_changed = true;

done:
	kfree(states);
	return ret;
}

/**
 * drm_atomic_normalize_zpos - calculate normalized zpos values for all crtcs
 * @dev: DRM device
 * @state: atomic state of DRM device
 *
 * This function calculates normalized zpos value for all modified planes in
 * the provided atomic state of DRM device.
 *
 * For every CRTC this function checks new states of all planes assigned to
 * it and calculates normalized zpos value for these planes. Planes are compared
 * first by their zpos values, then by plane id (if zpos is equal). The plane
 * with lowest zpos value is at the bottom. The &drm_plane_state.normalized_zpos
 * is then filled with unique values from 0 to number of active planes in crtc
 * minus one.
 *
 * RETURNS
 * Zero for success or -errno
 */
int drm_atomic_normalize_zpos(struct drm_device *dev,
			      struct drm_atomic_state *state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	struct drm_plane *plane;
	struct drm_plane_state *old_plane_state, *new_plane_state;
	int i, ret = 0;

	for_each_oldnew_plane_in_state(state, plane, old_plane_state, new_plane_state, i) {
		crtc = new_plane_state->crtc;
		if (!crtc)
			continue;
		if (old_plane_state->zpos != new_plane_state->zpos) {
			new_crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
			new_crtc_state->zpos_changed = true;
		}
	}

	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
		if (old_crtc_state->plane_mask != new_crtc_state->plane_mask ||
		    new_crtc_state->zpos_changed) {
			ret = drm_atomic_helper_crtc_normalize_zpos(crtc,
								    new_crtc_state);
			if (ret)
				return ret;
		}
	}
	return 0;
}
EXPORT_SYMBOL(drm_atomic_normalize_zpos);

/**
 * drm_plane_create_blend_mode_property - create a new blend mode property
 * @plane: drm plane
 * @supported_modes: bitmask of supported modes, must include
 *		     BIT(DRM_MODE_BLEND_PREMULTI). Current DRM assumption is
 *		     that alpha is premultiplied, and old userspace can break if
 *		     the property defaults to anything else.
 *
 * This creates a new property describing the blend mode.
 *
 * The property exposed to userspace is an enumeration property (see
 * drm_property_create_enum()) called "pixel blend mode" and has the
 * following enumeration values:
 *
 * "None":
 *	Blend formula that ignores the pixel alpha.
 *
 * "Pre-multiplied":
 *	Blend formula that assumes the pixel color values have been already
 *	pre-multiplied with the alpha channel values.
 *
 * "Coverage":
 *	Blend formula that assumes the pixel color values have not been
 *	pre-multiplied and will do so when blending them to the background color
 *	values.
 *
 * RETURNS:
 * Zero for success or -errno
 */
int drm_plane_create_blend_mode_property(struct drm_plane *plane,
					 unsigned int supported_modes)
{
	struct drm_device *dev = plane->dev;
	struct drm_property *prop;
	static const struct drm_prop_enum_list props[] = {
		{ DRM_MODE_BLEND_PIXEL_NONE, "None" },
		{ DRM_MODE_BLEND_PREMULTI, "Pre-multiplied" },
		{ DRM_MODE_BLEND_COVERAGE, "Coverage" },
	};
	unsigned int valid_mode_mask = BIT(DRM_MODE_BLEND_PIXEL_NONE) |
				       BIT(DRM_MODE_BLEND_PREMULTI)   |
				       BIT(DRM_MODE_BLEND_COVERAGE);
	int i;

	if (WARN_ON((supported_modes & ~valid_mode_mask) ||
		    ((supported_modes & BIT(DRM_MODE_BLEND_PREMULTI)) == 0)))
		return -EINVAL;

	prop = drm_property_create(dev, DRM_MODE_PROP_ENUM,
				   "pixel blend mode",
				   hweight32(supported_modes));
	if (!prop)
		return -ENOMEM;

	for (i = 0; i < ARRAY_SIZE(props); i++) {
		int ret;

		if (!(BIT(props[i].type) & supported_modes))
			continue;

		ret = drm_property_add_enum(prop, props[i].type,
					    props[i].name);

		if (ret) {
			drm_property_destroy(dev, prop);

			return ret;
		}
	}

	drm_object_attach_property(&plane->base, prop, DRM_MODE_BLEND_PREMULTI);
	plane->blend_mode_property = prop;

	return 0;
}
EXPORT_SYMBOL(drm_plane_create_blend_mode_property);