1 /* $NetBSD: drm_color_mgmt.h,v 1.2 2021/12/18 23:45:45 riastradh Exp $ */
2
3 /*
4 * Copyright (c) 2016 Intel Corporation
5 *
6 * Permission to use, copy, modify, distribute, and sell this software and its
7 * documentation for any purpose is hereby granted without fee, provided that
8 * the above copyright notice appear in all copies and that both that copyright
9 * notice and this permission notice appear in supporting documentation, and
10 * that the name of the copyright holders not be used in advertising or
11 * publicity pertaining to distribution of the software without specific,
12 * written prior permission. The copyright holders make no representations
13 * about the suitability of this software for any purpose. It is provided "as
14 * is" without express or implied warranty.
15 *
16 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
17 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
18 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
19 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
20 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
21 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
22 * OF THIS SOFTWARE.
23 */
24
25 #ifndef __DRM_COLOR_MGMT_H__
26 #define __DRM_COLOR_MGMT_H__
27
28 #include <linux/ctype.h>
29 #include <drm/drm_property.h>
30
31 struct drm_crtc;
32 struct drm_plane;
33
34 /**
35 * drm_color_lut_extract - clamp and round LUT entries
36 * @user_input: input value
37 * @bit_precision: number of bits the hw LUT supports
38 *
39 * Extract a degamma/gamma LUT value provided by user (in the form of
40 * &drm_color_lut entries) and round it to the precision supported by the
41 * hardware.
42 */
drm_color_lut_extract(u32 user_input,int bit_precision)43 static inline u32 drm_color_lut_extract(u32 user_input, int bit_precision)
44 {
45 u32 val = user_input;
46 u32 max = 0xffff >> (16 - bit_precision);
47
48 /* Round only if we're not using full precision. */
49 if (bit_precision < 16) {
50 val += 1UL << (16 - bit_precision - 1);
51 val >>= 16 - bit_precision;
52 }
53
54 return clamp_val(val, 0, max);
55 }
56
57 u64 drm_color_ctm_s31_32_to_qm_n(u64 user_input, u32 m, u32 n);
58
59 void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
60 uint degamma_lut_size,
61 bool has_ctm,
62 uint gamma_lut_size);
63
64 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
65 int gamma_size);
66
67 /**
68 * drm_color_lut_size - calculate the number of entries in the LUT
69 * @blob: blob containing the LUT
70 *
71 * Returns:
72 * The number of entries in the color LUT stored in @blob.
73 */
drm_color_lut_size(const struct drm_property_blob * blob)74 static inline int drm_color_lut_size(const struct drm_property_blob *blob)
75 {
76 return blob->length / sizeof(struct drm_color_lut);
77 }
78
79 enum drm_color_encoding {
80 DRM_COLOR_YCBCR_BT601,
81 DRM_COLOR_YCBCR_BT709,
82 DRM_COLOR_YCBCR_BT2020,
83 DRM_COLOR_ENCODING_MAX,
84 };
85
86 enum drm_color_range {
87 DRM_COLOR_YCBCR_LIMITED_RANGE,
88 DRM_COLOR_YCBCR_FULL_RANGE,
89 DRM_COLOR_RANGE_MAX,
90 };
91
92 int drm_plane_create_color_properties(struct drm_plane *plane,
93 u32 supported_encodings,
94 u32 supported_ranges,
95 enum drm_color_encoding default_encoding,
96 enum drm_color_range default_range);
97
98 /**
99 * enum drm_color_lut_tests - hw-specific LUT tests to perform
100 *
101 * The drm_color_lut_check() function takes a bitmask of the values here to
102 * determine which tests to apply to a userspace-provided LUT.
103 */
104 enum drm_color_lut_tests {
105 /**
106 * @DRM_COLOR_LUT_EQUAL_CHANNELS:
107 *
108 * Checks whether the entries of a LUT all have equal values for the
109 * red, green, and blue channels. Intended for hardware that only
110 * accepts a single value per LUT entry and assumes that value applies
111 * to all three color components.
112 */
113 DRM_COLOR_LUT_EQUAL_CHANNELS = BIT(0),
114
115 /**
116 * @DRM_COLOR_LUT_NON_DECREASING:
117 *
118 * Checks whether the entries of a LUT are always flat or increasing
119 * (never decreasing).
120 */
121 DRM_COLOR_LUT_NON_DECREASING = BIT(1),
122 };
123
124 int drm_color_lut_check(const struct drm_property_blob *lut, u32 tests);
125 #endif
126