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 <drm/drm_property.h>
28
29struct drm_crtc;
30struct drm_plane;
31
32/**
33 * drm_color_lut_extract - clamp and round LUT entries
34 * @user_input: input value
35 * @bit_precision: number of bits the hw LUT supports
36 *
37 * Extract a degamma/gamma LUT value provided by user (in the form of
38 * &drm_color_lut entries) and round it to the precision supported by the
39 * hardware.
40 */
41static inline u32 drm_color_lut_extract(u32 user_input, int bit_precision)
42{
43 u32 val = user_input;
44 u32 max = 0xffff >> (16 - bit_precision);
45
46 /* Round only if we're not using full precision. */
47 if (bit_precision < 16) {
48 val += 1UL << (16 - bit_precision - 1);
49 val >>= 16 - bit_precision;
50 }
51
52 return clamp_val(val, 0, max);
53}
54
55u64 drm_color_ctm_s31_32_to_qm_n(u64 user_input, u32 m, u32 n);
56
57void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
58 uint degamma_lut_size,
59 bool has_ctm,
60 uint gamma_lut_size);
61
62int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
63 int gamma_size);
64
65/**
66 * drm_color_lut_size - calculate the number of entries in the LUT
67 * @blob: blob containing the LUT
68 *
69 * Returns:
70 * The number of entries in the color LUT stored in @blob.
71 */
72static inline int drm_color_lut_size(const struct drm_property_blob *blob)
73{
74 return blob->length / sizeof(struct drm_color_lut);
75}
76
77enum drm_color_encoding {
78 DRM_COLOR_YCBCR_BT601,
79 DRM_COLOR_YCBCR_BT709,
80 DRM_COLOR_YCBCR_BT2020,
81 DRM_COLOR_ENCODING_MAX,
82};
83
84enum drm_color_range {
85 DRM_COLOR_YCBCR_LIMITED_RANGE,
86 DRM_COLOR_YCBCR_FULL_RANGE,
87 DRM_COLOR_RANGE_MAX,
88};
89
90int drm_plane_create_color_properties(struct drm_plane *plane,
91 u32 supported_encodings,
92 u32 supported_ranges,
93 enum drm_color_encoding default_encoding,
94 enum drm_color_range default_range);
95
96/**
97 * enum drm_color_lut_tests - hw-specific LUT tests to perform
98 *
99 * The drm_color_lut_check() function takes a bitmask of the values here to
100 * determine which tests to apply to a userspace-provided LUT.
101 */
102enum drm_color_lut_tests {
103 /**
104 * @DRM_COLOR_LUT_EQUAL_CHANNELS:
105 *
106 * Checks whether the entries of a LUT all have equal values for the
107 * red, green, and blue channels. Intended for hardware that only
108 * accepts a single value per LUT entry and assumes that value applies
109 * to all three color components.
110 */
111 DRM_COLOR_LUT_EQUAL_CHANNELS = BIT(0),
112
113 /**
114 * @DRM_COLOR_LUT_NON_DECREASING:
115 *
116 * Checks whether the entries of a LUT are always flat or increasing
117 * (never decreasing).
118 */
119 DRM_COLOR_LUT_NON_DECREASING = BIT(1),
120};
121
122int drm_color_lut_check(const struct drm_property_blob *lut, u32 tests);
123#endif
124

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