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