1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * v4l2-dv-timings - Internal header with dv-timings helper functions 4 * 5 * Copyright 2013 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 6 */ 7 8 #ifndef __V4L2_DV_TIMINGS_H 9 #define __V4L2_DV_TIMINGS_H 10 11 #include <linux/videodev2.h> 12 13 /* 14 * v4l2_dv_timings_presets: list of all dv_timings presets. 15 */ 16 extern const struct v4l2_dv_timings v4l2_dv_timings_presets[]; 17 18 /** 19 * typedef v4l2_check_dv_timings_fnc - timings check callback 20 * 21 * @t: the v4l2_dv_timings struct. 22 * @handle: a handle from the driver. 23 * 24 * Returns true if the given timings are valid. 25 */ 26 typedef bool v4l2_check_dv_timings_fnc(const struct v4l2_dv_timings *t, void *handle); 27 28 /** 29 * v4l2_valid_dv_timings() - are these timings valid? 30 * 31 * @t: the v4l2_dv_timings struct. 32 * @cap: the v4l2_dv_timings_cap capabilities. 33 * @fnc: callback to check if this timing is OK. May be NULL. 34 * @fnc_handle: a handle that is passed on to @fnc. 35 * 36 * Returns true if the given dv_timings struct is supported by the 37 * hardware capabilities and the callback function (if non-NULL), returns 38 * false otherwise. 39 */ 40 bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t, 41 const struct v4l2_dv_timings_cap *cap, 42 v4l2_check_dv_timings_fnc fnc, 43 void *fnc_handle); 44 45 /** 46 * v4l2_enum_dv_timings_cap() - Helper function to enumerate possible DV 47 * timings based on capabilities 48 * 49 * @t: the v4l2_enum_dv_timings struct. 50 * @cap: the v4l2_dv_timings_cap capabilities. 51 * @fnc: callback to check if this timing is OK. May be NULL. 52 * @fnc_handle: a handle that is passed on to @fnc. 53 * 54 * This enumerates dv_timings using the full list of possible CEA-861 and DMT 55 * timings, filtering out any timings that are not supported based on the 56 * hardware capabilities and the callback function (if non-NULL). 57 * 58 * If a valid timing for the given index is found, it will fill in @t and 59 * return 0, otherwise it returns -EINVAL. 60 */ 61 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t, 62 const struct v4l2_dv_timings_cap *cap, 63 v4l2_check_dv_timings_fnc fnc, 64 void *fnc_handle); 65 66 /** 67 * v4l2_find_dv_timings_cap() - Find the closest timings struct 68 * 69 * @t: the v4l2_enum_dv_timings struct. 70 * @cap: the v4l2_dv_timings_cap capabilities. 71 * @pclock_delta: maximum delta between t->pixelclock and the timing struct 72 * under consideration. 73 * @fnc: callback to check if a given timings struct is OK. May be NULL. 74 * @fnc_handle: a handle that is passed on to @fnc. 75 * 76 * This function tries to map the given timings to an entry in the 77 * full list of possible CEA-861 and DMT timings, filtering out any timings 78 * that are not supported based on the hardware capabilities and the callback 79 * function (if non-NULL). 80 * 81 * On success it will fill in @t with the found timings and it returns true. 82 * On failure it will return false. 83 */ 84 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t, 85 const struct v4l2_dv_timings_cap *cap, 86 unsigned pclock_delta, 87 v4l2_check_dv_timings_fnc fnc, 88 void *fnc_handle); 89 90 /** 91 * v4l2_find_dv_timings_cea861_vic() - find timings based on CEA-861 VIC 92 * @t: the timings data. 93 * @vic: CEA-861 VIC code 94 * 95 * On success it will fill in @t with the found timings and it returns true. 96 * On failure it will return false. 97 */ 98 bool v4l2_find_dv_timings_cea861_vic(struct v4l2_dv_timings *t, u8 vic); 99 100 /** 101 * v4l2_match_dv_timings() - do two timings match? 102 * 103 * @measured: the measured timings data. 104 * @standard: the timings according to the standard. 105 * @pclock_delta: maximum delta in Hz between standard->pixelclock and 106 * the measured timings. 107 * @match_reduced_fps: if true, then fail if V4L2_DV_FL_REDUCED_FPS does not 108 * match. 109 * 110 * Returns true if the two timings match, returns false otherwise. 111 */ 112 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *measured, 113 const struct v4l2_dv_timings *standard, 114 unsigned pclock_delta, bool match_reduced_fps); 115 116 /** 117 * v4l2_print_dv_timings() - log the contents of a dv_timings struct 118 * @dev_prefix:device prefix for each log line. 119 * @prefix: additional prefix for each log line, may be NULL. 120 * @t: the timings data. 121 * @detailed: if true, give a detailed log. 122 */ 123 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix, 124 const struct v4l2_dv_timings *t, bool detailed); 125 126 /** 127 * v4l2_detect_cvt - detect if the given timings follow the CVT standard 128 * 129 * @frame_height: the total height of the frame (including blanking) in lines. 130 * @hfreq: the horizontal frequency in Hz. 131 * @vsync: the height of the vertical sync in lines. 132 * @active_width: active width of image (does not include blanking). This 133 * information is needed only in case of version 2 of reduced blanking. 134 * In other cases, this parameter does not have any effect on timings. 135 * @polarities: the horizontal and vertical polarities (same as struct 136 * v4l2_bt_timings polarities). 137 * @interlaced: if this flag is true, it indicates interlaced format 138 * @fmt: the resulting timings. 139 * 140 * This function will attempt to detect if the given values correspond to a 141 * valid CVT format. If so, then it will return true, and fmt will be filled 142 * in with the found CVT timings. 143 */ 144 bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync, 145 unsigned active_width, u32 polarities, bool interlaced, 146 struct v4l2_dv_timings *fmt); 147 148 /** 149 * v4l2_detect_gtf - detect if the given timings follow the GTF standard 150 * 151 * @frame_height: the total height of the frame (including blanking) in lines. 152 * @hfreq: the horizontal frequency in Hz. 153 * @vsync: the height of the vertical sync in lines. 154 * @polarities: the horizontal and vertical polarities (same as struct 155 * v4l2_bt_timings polarities). 156 * @interlaced: if this flag is true, it indicates interlaced format 157 * @aspect: preferred aspect ratio. GTF has no method of determining the 158 * aspect ratio in order to derive the image width from the 159 * image height, so it has to be passed explicitly. Usually 160 * the native screen aspect ratio is used for this. If it 161 * is not filled in correctly, then 16:9 will be assumed. 162 * @fmt: the resulting timings. 163 * 164 * This function will attempt to detect if the given values correspond to a 165 * valid GTF format. If so, then it will return true, and fmt will be filled 166 * in with the found GTF timings. 167 */ 168 bool v4l2_detect_gtf(unsigned frame_height, unsigned hfreq, unsigned vsync, 169 u32 polarities, bool interlaced, struct v4l2_fract aspect, 170 struct v4l2_dv_timings *fmt); 171 172 /** 173 * v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes 174 * 0x15 and 0x16 from the EDID. 175 * 176 * @hor_landscape: byte 0x15 from the EDID. 177 * @vert_portrait: byte 0x16 from the EDID. 178 * 179 * Determines the aspect ratio from the EDID. 180 * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2: 181 * "Horizontal and Vertical Screen Size or Aspect Ratio" 182 */ 183 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait); 184 185 /** 186 * v4l2_dv_timings_aspect_ratio - calculate the aspect ratio based on the 187 * v4l2_dv_timings information. 188 * 189 * @t: the timings data. 190 */ 191 struct v4l2_fract v4l2_dv_timings_aspect_ratio(const struct v4l2_dv_timings *t); 192 193 /** 194 * can_reduce_fps - check if conditions for reduced fps are true. 195 * @bt: v4l2 timing structure 196 * 197 * For different timings reduced fps is allowed if the following conditions 198 * are met: 199 * 200 * - For CVT timings: if reduced blanking v2 (vsync == 8) is true. 201 * - For CEA861 timings: if %V4L2_DV_FL_CAN_REDUCE_FPS flag is true. 202 */ 203 static inline bool can_reduce_fps(struct v4l2_bt_timings *bt) 204 { 205 if ((bt->standards & V4L2_DV_BT_STD_CVT) && (bt->vsync == 8)) 206 return true; 207 208 if ((bt->standards & V4L2_DV_BT_STD_CEA861) && 209 (bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS)) 210 return true; 211 212 return false; 213 } 214 215 /** 216 * struct v4l2_hdmi_rx_colorimetry - describes the HDMI colorimetry information 217 * @colorspace: enum v4l2_colorspace, the colorspace 218 * @ycbcr_enc: enum v4l2_ycbcr_encoding, Y'CbCr encoding 219 * @quantization: enum v4l2_quantization, colorspace quantization 220 * @xfer_func: enum v4l2_xfer_func, colorspace transfer function 221 */ 222 struct v4l2_hdmi_colorimetry { 223 enum v4l2_colorspace colorspace; 224 enum v4l2_ycbcr_encoding ycbcr_enc; 225 enum v4l2_quantization quantization; 226 enum v4l2_xfer_func xfer_func; 227 }; 228 229 struct hdmi_avi_infoframe; 230 struct hdmi_vendor_infoframe; 231 232 struct v4l2_hdmi_colorimetry 233 v4l2_hdmi_rx_colorimetry(const struct hdmi_avi_infoframe *avi, 234 const struct hdmi_vendor_infoframe *hdmi, 235 unsigned int height); 236 237 #endif 238