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 
29 struct drm_crtc;
30 struct 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  */
drm_color_lut_extract(u32 user_input,int bit_precision)41 static 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 
55 u64 drm_color_ctm_s31_32_to_qm_n(u64 user_input, u32 m, u32 n);
56 
57 void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
58 				uint degamma_lut_size,
59 				bool has_ctm,
60 				uint gamma_lut_size);
61 
62 int 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  */
drm_color_lut_size(const struct drm_property_blob * blob)72 static inline int drm_color_lut_size(const struct drm_property_blob *blob)
73 {
74 	return blob->length / sizeof(struct drm_color_lut);
75 }
76 
77 enum 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 
84 enum drm_color_range {
85 	DRM_COLOR_YCBCR_LIMITED_RANGE,
86 	DRM_COLOR_YCBCR_FULL_RANGE,
87 	DRM_COLOR_RANGE_MAX,
88 };
89 
90 int 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  */
102 enum 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 
122 int drm_color_lut_check(const struct drm_property_blob *lut, u32 tests);
123 #endif
124