1/*
2 * Copyright (c) 2016 Intel Corporation
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission. The copyright holders make no representations
11 * about the suitability of this software for any purpose. It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#ifndef __DRM_COLOR_MGMT_H__
24#define __DRM_COLOR_MGMT_H__
25
26#include <linux/ctype.h>
27#include <linux/math64.h>
28#include <drm/drm_property.h>
29
30struct drm_crtc;
31struct drm_plane;
32
33/**
34 * drm_color_lut_extract - clamp and round LUT entries
35 * @user_input: input value
36 * @bit_precision: number of bits the hw LUT supports
37 *
38 * Extract a degamma/gamma LUT value provided by user (in the form of
39 * &drm_color_lut entries) and round it to the precision supported by the
40 * hardware, following OpenGL int<->float conversion rules
41 * (see eg. OpenGL 4.6 specification - 2.3.5 Fixed-Point Data Conversions).
42 */
43static inline u32 drm_color_lut_extract(u32 user_input, int bit_precision)
44{
45 if (bit_precision > 16)
46 return DIV_ROUND_CLOSEST_ULL(mul_u32_u32(user_input, (1 << bit_precision) - 1),
47 (1 << 16) - 1);
48 else
49 return DIV_ROUND_CLOSEST(user_input * ((1 << bit_precision) - 1),
50 (1 << 16) - 1);
51}
52
53u64 drm_color_ctm_s31_32_to_qm_n(u64 user_input, u32 m, u32 n);
54
55void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
56 uint degamma_lut_size,
57 bool has_ctm,
58 uint gamma_lut_size);
59
60int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
61 int gamma_size);
62
63/**
64 * drm_color_lut_size - calculate the number of entries in the LUT
65 * @blob: blob containing the LUT
66 *
67 * Returns:
68 * The number of entries in the color LUT stored in @blob.
69 */
70static inline int drm_color_lut_size(const struct drm_property_blob *blob)
71{
72 return blob->length / sizeof(struct drm_color_lut);
73}
74
75enum drm_color_encoding {
76 DRM_COLOR_YCBCR_BT601,
77 DRM_COLOR_YCBCR_BT709,
78 DRM_COLOR_YCBCR_BT2020,
79 DRM_COLOR_ENCODING_MAX,
80};
81
82enum drm_color_range {
83 DRM_COLOR_YCBCR_LIMITED_RANGE,
84 DRM_COLOR_YCBCR_FULL_RANGE,
85 DRM_COLOR_RANGE_MAX,
86};
87
88int drm_plane_create_color_properties(struct drm_plane *plane,
89 u32 supported_encodings,
90 u32 supported_ranges,
91 enum drm_color_encoding default_encoding,
92 enum drm_color_range default_range);
93
94/**
95 * enum drm_color_lut_tests - hw-specific LUT tests to perform
96 *
97 * The drm_color_lut_check() function takes a bitmask of the values here to
98 * determine which tests to apply to a userspace-provided LUT.
99 */
100enum drm_color_lut_tests {
101 /**
102 * @DRM_COLOR_LUT_EQUAL_CHANNELS:
103 *
104 * Checks whether the entries of a LUT all have equal values for the
105 * red, green, and blue channels. Intended for hardware that only
106 * accepts a single value per LUT entry and assumes that value applies
107 * to all three color components.
108 */
109 DRM_COLOR_LUT_EQUAL_CHANNELS = BIT(0),
110
111 /**
112 * @DRM_COLOR_LUT_NON_DECREASING:
113 *
114 * Checks whether the entries of a LUT are always flat or increasing
115 * (never decreasing).
116 */
117 DRM_COLOR_LUT_NON_DECREASING = BIT(1),
118};
119
120int drm_color_lut_check(const struct drm_property_blob *lut, u32 tests);
121#endif
122

source code of linux/include/drm/drm_color_mgmt.h