1 /* 2 * v4l2-dv-timings - dv-timings helper functions 3 * 4 * Copyright 2013 Cisco Systems, Inc. and/or its affiliates. All rights reserved. 5 * 6 * This program is free software; you may redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; version 2 of the License. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 11 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 12 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 13 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 14 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 15 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 16 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 17 * SOFTWARE. 18 * 19 */ 20 21 #include <linux/module.h> 22 #include <linux/types.h> 23 #include <linux/kernel.h> 24 #include <linux/errno.h> 25 #include <linux/videodev2.h> 26 #include <linux/v4l2-dv-timings.h> 27 #include <media/v4l2-dv-timings.h> 28 #include <linux/math64.h> 29 30 MODULE_AUTHOR("Hans Verkuil"); 31 MODULE_DESCRIPTION("V4L2 DV Timings Helper Functions"); 32 MODULE_LICENSE("GPL"); 33 34 const struct v4l2_dv_timings v4l2_dv_timings_presets[] = { 35 V4L2_DV_BT_CEA_640X480P59_94, 36 V4L2_DV_BT_CEA_720X480I59_94, 37 V4L2_DV_BT_CEA_720X480P59_94, 38 V4L2_DV_BT_CEA_720X576I50, 39 V4L2_DV_BT_CEA_720X576P50, 40 V4L2_DV_BT_CEA_1280X720P24, 41 V4L2_DV_BT_CEA_1280X720P25, 42 V4L2_DV_BT_CEA_1280X720P30, 43 V4L2_DV_BT_CEA_1280X720P50, 44 V4L2_DV_BT_CEA_1280X720P60, 45 V4L2_DV_BT_CEA_1920X1080P24, 46 V4L2_DV_BT_CEA_1920X1080P25, 47 V4L2_DV_BT_CEA_1920X1080P30, 48 V4L2_DV_BT_CEA_1920X1080I50, 49 V4L2_DV_BT_CEA_1920X1080P50, 50 V4L2_DV_BT_CEA_1920X1080I60, 51 V4L2_DV_BT_CEA_1920X1080P60, 52 V4L2_DV_BT_DMT_640X350P85, 53 V4L2_DV_BT_DMT_640X400P85, 54 V4L2_DV_BT_DMT_720X400P85, 55 V4L2_DV_BT_DMT_640X480P72, 56 V4L2_DV_BT_DMT_640X480P75, 57 V4L2_DV_BT_DMT_640X480P85, 58 V4L2_DV_BT_DMT_800X600P56, 59 V4L2_DV_BT_DMT_800X600P60, 60 V4L2_DV_BT_DMT_800X600P72, 61 V4L2_DV_BT_DMT_800X600P75, 62 V4L2_DV_BT_DMT_800X600P85, 63 V4L2_DV_BT_DMT_800X600P120_RB, 64 V4L2_DV_BT_DMT_848X480P60, 65 V4L2_DV_BT_DMT_1024X768I43, 66 V4L2_DV_BT_DMT_1024X768P60, 67 V4L2_DV_BT_DMT_1024X768P70, 68 V4L2_DV_BT_DMT_1024X768P75, 69 V4L2_DV_BT_DMT_1024X768P85, 70 V4L2_DV_BT_DMT_1024X768P120_RB, 71 V4L2_DV_BT_DMT_1152X864P75, 72 V4L2_DV_BT_DMT_1280X768P60_RB, 73 V4L2_DV_BT_DMT_1280X768P60, 74 V4L2_DV_BT_DMT_1280X768P75, 75 V4L2_DV_BT_DMT_1280X768P85, 76 V4L2_DV_BT_DMT_1280X768P120_RB, 77 V4L2_DV_BT_DMT_1280X800P60_RB, 78 V4L2_DV_BT_DMT_1280X800P60, 79 V4L2_DV_BT_DMT_1280X800P75, 80 V4L2_DV_BT_DMT_1280X800P85, 81 V4L2_DV_BT_DMT_1280X800P120_RB, 82 V4L2_DV_BT_DMT_1280X960P60, 83 V4L2_DV_BT_DMT_1280X960P85, 84 V4L2_DV_BT_DMT_1280X960P120_RB, 85 V4L2_DV_BT_DMT_1280X1024P60, 86 V4L2_DV_BT_DMT_1280X1024P75, 87 V4L2_DV_BT_DMT_1280X1024P85, 88 V4L2_DV_BT_DMT_1280X1024P120_RB, 89 V4L2_DV_BT_DMT_1360X768P60, 90 V4L2_DV_BT_DMT_1360X768P120_RB, 91 V4L2_DV_BT_DMT_1366X768P60, 92 V4L2_DV_BT_DMT_1366X768P60_RB, 93 V4L2_DV_BT_DMT_1400X1050P60_RB, 94 V4L2_DV_BT_DMT_1400X1050P60, 95 V4L2_DV_BT_DMT_1400X1050P75, 96 V4L2_DV_BT_DMT_1400X1050P85, 97 V4L2_DV_BT_DMT_1400X1050P120_RB, 98 V4L2_DV_BT_DMT_1440X900P60_RB, 99 V4L2_DV_BT_DMT_1440X900P60, 100 V4L2_DV_BT_DMT_1440X900P75, 101 V4L2_DV_BT_DMT_1440X900P85, 102 V4L2_DV_BT_DMT_1440X900P120_RB, 103 V4L2_DV_BT_DMT_1600X900P60_RB, 104 V4L2_DV_BT_DMT_1600X1200P60, 105 V4L2_DV_BT_DMT_1600X1200P65, 106 V4L2_DV_BT_DMT_1600X1200P70, 107 V4L2_DV_BT_DMT_1600X1200P75, 108 V4L2_DV_BT_DMT_1600X1200P85, 109 V4L2_DV_BT_DMT_1600X1200P120_RB, 110 V4L2_DV_BT_DMT_1680X1050P60_RB, 111 V4L2_DV_BT_DMT_1680X1050P60, 112 V4L2_DV_BT_DMT_1680X1050P75, 113 V4L2_DV_BT_DMT_1680X1050P85, 114 V4L2_DV_BT_DMT_1680X1050P120_RB, 115 V4L2_DV_BT_DMT_1792X1344P60, 116 V4L2_DV_BT_DMT_1792X1344P75, 117 V4L2_DV_BT_DMT_1792X1344P120_RB, 118 V4L2_DV_BT_DMT_1856X1392P60, 119 V4L2_DV_BT_DMT_1856X1392P75, 120 V4L2_DV_BT_DMT_1856X1392P120_RB, 121 V4L2_DV_BT_DMT_1920X1200P60_RB, 122 V4L2_DV_BT_DMT_1920X1200P60, 123 V4L2_DV_BT_DMT_1920X1200P75, 124 V4L2_DV_BT_DMT_1920X1200P85, 125 V4L2_DV_BT_DMT_1920X1200P120_RB, 126 V4L2_DV_BT_DMT_1920X1440P60, 127 V4L2_DV_BT_DMT_1920X1440P75, 128 V4L2_DV_BT_DMT_1920X1440P120_RB, 129 V4L2_DV_BT_DMT_2048X1152P60_RB, 130 V4L2_DV_BT_DMT_2560X1600P60_RB, 131 V4L2_DV_BT_DMT_2560X1600P60, 132 V4L2_DV_BT_DMT_2560X1600P75, 133 V4L2_DV_BT_DMT_2560X1600P85, 134 V4L2_DV_BT_DMT_2560X1600P120_RB, 135 V4L2_DV_BT_CEA_3840X2160P24, 136 V4L2_DV_BT_CEA_3840X2160P25, 137 V4L2_DV_BT_CEA_3840X2160P30, 138 V4L2_DV_BT_CEA_3840X2160P50, 139 V4L2_DV_BT_CEA_3840X2160P60, 140 V4L2_DV_BT_CEA_4096X2160P24, 141 V4L2_DV_BT_CEA_4096X2160P25, 142 V4L2_DV_BT_CEA_4096X2160P30, 143 V4L2_DV_BT_CEA_4096X2160P50, 144 V4L2_DV_BT_DMT_4096X2160P59_94_RB, 145 V4L2_DV_BT_CEA_4096X2160P60, 146 { } 147 }; 148 EXPORT_SYMBOL_GPL(v4l2_dv_timings_presets); 149 150 bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t, 151 const struct v4l2_dv_timings_cap *dvcap, 152 v4l2_check_dv_timings_fnc fnc, 153 void *fnc_handle) 154 { 155 const struct v4l2_bt_timings *bt = &t->bt; 156 const struct v4l2_bt_timings_cap *cap = &dvcap->bt; 157 u32 caps = cap->capabilities; 158 159 if (t->type != V4L2_DV_BT_656_1120) 160 return false; 161 if (t->type != dvcap->type || 162 bt->height < cap->min_height || 163 bt->height > cap->max_height || 164 bt->width < cap->min_width || 165 bt->width > cap->max_width || 166 bt->pixelclock < cap->min_pixelclock || 167 bt->pixelclock > cap->max_pixelclock || 168 (!(caps & V4L2_DV_BT_CAP_CUSTOM) && 169 cap->standards && bt->standards && 170 !(bt->standards & cap->standards)) || 171 (bt->interlaced && !(caps & V4L2_DV_BT_CAP_INTERLACED)) || 172 (!bt->interlaced && !(caps & V4L2_DV_BT_CAP_PROGRESSIVE))) 173 return false; 174 return fnc == NULL || fnc(t, fnc_handle); 175 } 176 EXPORT_SYMBOL_GPL(v4l2_valid_dv_timings); 177 178 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t, 179 const struct v4l2_dv_timings_cap *cap, 180 v4l2_check_dv_timings_fnc fnc, 181 void *fnc_handle) 182 { 183 u32 i, idx; 184 185 memset(t->reserved, 0, sizeof(t->reserved)); 186 for (i = idx = 0; v4l2_dv_timings_presets[i].bt.width; i++) { 187 if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap, 188 fnc, fnc_handle) && 189 idx++ == t->index) { 190 t->timings = v4l2_dv_timings_presets[i]; 191 return 0; 192 } 193 } 194 return -EINVAL; 195 } 196 EXPORT_SYMBOL_GPL(v4l2_enum_dv_timings_cap); 197 198 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t, 199 const struct v4l2_dv_timings_cap *cap, 200 unsigned pclock_delta, 201 v4l2_check_dv_timings_fnc fnc, 202 void *fnc_handle) 203 { 204 int i; 205 206 if (!v4l2_valid_dv_timings(t, cap, fnc, fnc_handle)) 207 return false; 208 209 for (i = 0; i < v4l2_dv_timings_presets[i].bt.width; i++) { 210 if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap, 211 fnc, fnc_handle) && 212 v4l2_match_dv_timings(t, v4l2_dv_timings_presets + i, 213 pclock_delta, false)) { 214 u32 flags = t->bt.flags & V4L2_DV_FL_REDUCED_FPS; 215 216 *t = v4l2_dv_timings_presets[i]; 217 if (can_reduce_fps(&t->bt)) 218 t->bt.flags |= flags; 219 220 return true; 221 } 222 } 223 return false; 224 } 225 EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cap); 226 227 /** 228 * v4l2_match_dv_timings - check if two timings match 229 * @t1 - compare this v4l2_dv_timings struct... 230 * @t2 - with this struct. 231 * @pclock_delta - the allowed pixelclock deviation. 232 * @match_reduced_fps - if true, then fail if V4L2_DV_FL_REDUCED_FPS does not 233 * match. 234 * 235 * Compare t1 with t2 with a given margin of error for the pixelclock. 236 */ 237 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *t1, 238 const struct v4l2_dv_timings *t2, 239 unsigned pclock_delta, bool match_reduced_fps) 240 { 241 if (t1->type != t2->type || t1->type != V4L2_DV_BT_656_1120) 242 return false; 243 if (t1->bt.width == t2->bt.width && 244 t1->bt.height == t2->bt.height && 245 t1->bt.interlaced == t2->bt.interlaced && 246 t1->bt.polarities == t2->bt.polarities && 247 t1->bt.pixelclock >= t2->bt.pixelclock - pclock_delta && 248 t1->bt.pixelclock <= t2->bt.pixelclock + pclock_delta && 249 t1->bt.hfrontporch == t2->bt.hfrontporch && 250 t1->bt.hsync == t2->bt.hsync && 251 t1->bt.hbackporch == t2->bt.hbackporch && 252 t1->bt.vfrontporch == t2->bt.vfrontporch && 253 t1->bt.vsync == t2->bt.vsync && 254 t1->bt.vbackporch == t2->bt.vbackporch && 255 (!match_reduced_fps || 256 (t1->bt.flags & V4L2_DV_FL_REDUCED_FPS) == 257 (t2->bt.flags & V4L2_DV_FL_REDUCED_FPS)) && 258 (!t1->bt.interlaced || 259 (t1->bt.il_vfrontporch == t2->bt.il_vfrontporch && 260 t1->bt.il_vsync == t2->bt.il_vsync && 261 t1->bt.il_vbackporch == t2->bt.il_vbackporch))) 262 return true; 263 return false; 264 } 265 EXPORT_SYMBOL_GPL(v4l2_match_dv_timings); 266 267 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix, 268 const struct v4l2_dv_timings *t, bool detailed) 269 { 270 const struct v4l2_bt_timings *bt = &t->bt; 271 u32 htot, vtot; 272 u32 fps; 273 274 if (t->type != V4L2_DV_BT_656_1120) 275 return; 276 277 htot = V4L2_DV_BT_FRAME_WIDTH(bt); 278 vtot = V4L2_DV_BT_FRAME_HEIGHT(bt); 279 if (bt->interlaced) 280 vtot /= 2; 281 282 fps = (htot * vtot) > 0 ? div_u64((100 * (u64)bt->pixelclock), 283 (htot * vtot)) : 0; 284 285 if (prefix == NULL) 286 prefix = ""; 287 288 pr_info("%s: %s%ux%u%s%u.%u (%ux%u)\n", dev_prefix, prefix, 289 bt->width, bt->height, bt->interlaced ? "i" : "p", 290 fps / 100, fps % 100, htot, vtot); 291 292 if (!detailed) 293 return; 294 295 pr_info("%s: horizontal: fp = %u, %ssync = %u, bp = %u\n", 296 dev_prefix, bt->hfrontporch, 297 (bt->polarities & V4L2_DV_HSYNC_POS_POL) ? "+" : "-", 298 bt->hsync, bt->hbackporch); 299 pr_info("%s: vertical: fp = %u, %ssync = %u, bp = %u\n", 300 dev_prefix, bt->vfrontporch, 301 (bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-", 302 bt->vsync, bt->vbackporch); 303 if (bt->interlaced) 304 pr_info("%s: vertical bottom field: fp = %u, %ssync = %u, bp = %u\n", 305 dev_prefix, bt->il_vfrontporch, 306 (bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-", 307 bt->il_vsync, bt->il_vbackporch); 308 pr_info("%s: pixelclock: %llu\n", dev_prefix, bt->pixelclock); 309 pr_info("%s: flags (0x%x):%s%s%s%s%s%s%s\n", dev_prefix, bt->flags, 310 (bt->flags & V4L2_DV_FL_REDUCED_BLANKING) ? 311 " REDUCED_BLANKING" : "", 312 ((bt->flags & V4L2_DV_FL_REDUCED_BLANKING) && 313 bt->vsync == 8) ? " (V2)" : "", 314 (bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS) ? 315 " CAN_REDUCE_FPS" : "", 316 (bt->flags & V4L2_DV_FL_REDUCED_FPS) ? 317 " REDUCED_FPS" : "", 318 (bt->flags & V4L2_DV_FL_HALF_LINE) ? 319 " HALF_LINE" : "", 320 (bt->flags & V4L2_DV_FL_IS_CE_VIDEO) ? 321 " CE_VIDEO" : "", 322 (bt->flags & V4L2_DV_FL_FIRST_FIELD_EXTRA_LINE) ? 323 " FIRST_FIELD_EXTRA_LINE" : ""); 324 pr_info("%s: standards (0x%x):%s%s%s%s%s\n", dev_prefix, bt->standards, 325 (bt->standards & V4L2_DV_BT_STD_CEA861) ? " CEA" : "", 326 (bt->standards & V4L2_DV_BT_STD_DMT) ? " DMT" : "", 327 (bt->standards & V4L2_DV_BT_STD_CVT) ? " CVT" : "", 328 (bt->standards & V4L2_DV_BT_STD_GTF) ? " GTF" : "", 329 (bt->standards & V4L2_DV_BT_STD_SDI) ? " SDI" : ""); 330 } 331 EXPORT_SYMBOL_GPL(v4l2_print_dv_timings); 332 333 /* 334 * CVT defines 335 * Based on Coordinated Video Timings Standard 336 * version 1.1 September 10, 2003 337 */ 338 339 #define CVT_PXL_CLK_GRAN 250000 /* pixel clock granularity */ 340 #define CVT_PXL_CLK_GRAN_RB_V2 1000 /* granularity for reduced blanking v2*/ 341 342 /* Normal blanking */ 343 #define CVT_MIN_V_BPORCH 7 /* lines */ 344 #define CVT_MIN_V_PORCH_RND 3 /* lines */ 345 #define CVT_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */ 346 #define CVT_HSYNC_PERCENT 8 /* nominal hsync as percentage of line */ 347 348 /* Normal blanking for CVT uses GTF to calculate horizontal blanking */ 349 #define CVT_CELL_GRAN 8 /* character cell granularity */ 350 #define CVT_M 600 /* blanking formula gradient */ 351 #define CVT_C 40 /* blanking formula offset */ 352 #define CVT_K 128 /* blanking formula scaling factor */ 353 #define CVT_J 20 /* blanking formula scaling factor */ 354 #define CVT_C_PRIME (((CVT_C - CVT_J) * CVT_K / 256) + CVT_J) 355 #define CVT_M_PRIME (CVT_K * CVT_M / 256) 356 357 /* Reduced Blanking */ 358 #define CVT_RB_MIN_V_BPORCH 7 /* lines */ 359 #define CVT_RB_V_FPORCH 3 /* lines */ 360 #define CVT_RB_MIN_V_BLANK 460 /* us */ 361 #define CVT_RB_H_SYNC 32 /* pixels */ 362 #define CVT_RB_H_BLANK 160 /* pixels */ 363 /* Reduce blanking Version 2 */ 364 #define CVT_RB_V2_H_BLANK 80 /* pixels */ 365 #define CVT_RB_MIN_V_FPORCH 3 /* lines */ 366 #define CVT_RB_V2_MIN_V_FPORCH 1 /* lines */ 367 #define CVT_RB_V_BPORCH 6 /* lines */ 368 369 /** v4l2_detect_cvt - detect if the given timings follow the CVT standard 370 * @frame_height - the total height of the frame (including blanking) in lines. 371 * @hfreq - the horizontal frequency in Hz. 372 * @vsync - the height of the vertical sync in lines. 373 * @active_width - active width of image (does not include blanking). This 374 * information is needed only in case of version 2 of reduced blanking. 375 * In other cases, this parameter does not have any effect on timings. 376 * @polarities - the horizontal and vertical polarities (same as struct 377 * v4l2_bt_timings polarities). 378 * @interlaced - if this flag is true, it indicates interlaced format 379 * @fmt - the resulting timings. 380 * 381 * This function will attempt to detect if the given values correspond to a 382 * valid CVT format. If so, then it will return true, and fmt will be filled 383 * in with the found CVT timings. 384 */ 385 bool v4l2_detect_cvt(unsigned frame_height, 386 unsigned hfreq, 387 unsigned vsync, 388 unsigned active_width, 389 u32 polarities, 390 bool interlaced, 391 struct v4l2_dv_timings *fmt) 392 { 393 int v_fp, v_bp, h_fp, h_bp, hsync; 394 int frame_width, image_height, image_width; 395 bool reduced_blanking; 396 bool rb_v2 = false; 397 unsigned pix_clk; 398 399 if (vsync < 4 || vsync > 8) 400 return false; 401 402 if (polarities == V4L2_DV_VSYNC_POS_POL) 403 reduced_blanking = false; 404 else if (polarities == V4L2_DV_HSYNC_POS_POL) 405 reduced_blanking = true; 406 else 407 return false; 408 409 if (reduced_blanking && vsync == 8) 410 rb_v2 = true; 411 412 if (rb_v2 && active_width == 0) 413 return false; 414 415 if (!rb_v2 && vsync > 7) 416 return false; 417 418 if (hfreq == 0) 419 return false; 420 421 /* Vertical */ 422 if (reduced_blanking) { 423 if (rb_v2) { 424 v_bp = CVT_RB_V_BPORCH; 425 v_fp = (CVT_RB_MIN_V_BLANK * hfreq) / 1000000 + 1; 426 v_fp -= vsync + v_bp; 427 428 if (v_fp < CVT_RB_V2_MIN_V_FPORCH) 429 v_fp = CVT_RB_V2_MIN_V_FPORCH; 430 } else { 431 v_fp = CVT_RB_V_FPORCH; 432 v_bp = (CVT_RB_MIN_V_BLANK * hfreq) / 1000000 + 1; 433 v_bp -= vsync + v_fp; 434 435 if (v_bp < CVT_RB_MIN_V_BPORCH) 436 v_bp = CVT_RB_MIN_V_BPORCH; 437 } 438 } else { 439 v_fp = CVT_MIN_V_PORCH_RND; 440 v_bp = (CVT_MIN_VSYNC_BP * hfreq) / 1000000 + 1 - vsync; 441 442 if (v_bp < CVT_MIN_V_BPORCH) 443 v_bp = CVT_MIN_V_BPORCH; 444 } 445 446 if (interlaced) 447 image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1; 448 else 449 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1; 450 451 if (image_height < 0) 452 return false; 453 454 /* Aspect ratio based on vsync */ 455 switch (vsync) { 456 case 4: 457 image_width = (image_height * 4) / 3; 458 break; 459 case 5: 460 image_width = (image_height * 16) / 9; 461 break; 462 case 6: 463 image_width = (image_height * 16) / 10; 464 break; 465 case 7: 466 /* special case */ 467 if (image_height == 1024) 468 image_width = (image_height * 5) / 4; 469 else if (image_height == 768) 470 image_width = (image_height * 15) / 9; 471 else 472 return false; 473 break; 474 case 8: 475 image_width = active_width; 476 break; 477 default: 478 return false; 479 } 480 481 if (!rb_v2) 482 image_width = image_width & ~7; 483 484 /* Horizontal */ 485 if (reduced_blanking) { 486 int h_blank; 487 int clk_gran; 488 489 h_blank = rb_v2 ? CVT_RB_V2_H_BLANK : CVT_RB_H_BLANK; 490 clk_gran = rb_v2 ? CVT_PXL_CLK_GRAN_RB_V2 : CVT_PXL_CLK_GRAN; 491 492 pix_clk = (image_width + h_blank) * hfreq; 493 pix_clk = (pix_clk / clk_gran) * clk_gran; 494 495 h_bp = h_blank / 2; 496 hsync = CVT_RB_H_SYNC; 497 h_fp = h_blank - h_bp - hsync; 498 499 frame_width = image_width + h_blank; 500 } else { 501 unsigned ideal_duty_cycle_per_myriad = 502 100 * CVT_C_PRIME - (CVT_M_PRIME * 100000) / hfreq; 503 int h_blank; 504 505 if (ideal_duty_cycle_per_myriad < 2000) 506 ideal_duty_cycle_per_myriad = 2000; 507 508 h_blank = image_width * ideal_duty_cycle_per_myriad / 509 (10000 - ideal_duty_cycle_per_myriad); 510 h_blank = (h_blank / (2 * CVT_CELL_GRAN)) * 2 * CVT_CELL_GRAN; 511 512 pix_clk = (image_width + h_blank) * hfreq; 513 pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN; 514 515 h_bp = h_blank / 2; 516 frame_width = image_width + h_blank; 517 518 hsync = frame_width * CVT_HSYNC_PERCENT / 100; 519 hsync = (hsync / CVT_CELL_GRAN) * CVT_CELL_GRAN; 520 h_fp = h_blank - hsync - h_bp; 521 } 522 523 fmt->type = V4L2_DV_BT_656_1120; 524 fmt->bt.polarities = polarities; 525 fmt->bt.width = image_width; 526 fmt->bt.height = image_height; 527 fmt->bt.hfrontporch = h_fp; 528 fmt->bt.vfrontporch = v_fp; 529 fmt->bt.hsync = hsync; 530 fmt->bt.vsync = vsync; 531 fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync; 532 533 if (!interlaced) { 534 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync; 535 fmt->bt.interlaced = V4L2_DV_PROGRESSIVE; 536 } else { 537 fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp - 538 2 * vsync) / 2; 539 fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp - 540 2 * vsync - fmt->bt.vbackporch; 541 fmt->bt.il_vfrontporch = v_fp; 542 fmt->bt.il_vsync = vsync; 543 fmt->bt.flags |= V4L2_DV_FL_HALF_LINE; 544 fmt->bt.interlaced = V4L2_DV_INTERLACED; 545 } 546 547 fmt->bt.pixelclock = pix_clk; 548 fmt->bt.standards = V4L2_DV_BT_STD_CVT; 549 550 if (reduced_blanking) 551 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING; 552 553 return true; 554 } 555 EXPORT_SYMBOL_GPL(v4l2_detect_cvt); 556 557 /* 558 * GTF defines 559 * Based on Generalized Timing Formula Standard 560 * Version 1.1 September 2, 1999 561 */ 562 563 #define GTF_PXL_CLK_GRAN 250000 /* pixel clock granularity */ 564 565 #define GTF_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */ 566 #define GTF_V_FP 1 /* vertical front porch (lines) */ 567 #define GTF_CELL_GRAN 8 /* character cell granularity */ 568 569 /* Default */ 570 #define GTF_D_M 600 /* blanking formula gradient */ 571 #define GTF_D_C 40 /* blanking formula offset */ 572 #define GTF_D_K 128 /* blanking formula scaling factor */ 573 #define GTF_D_J 20 /* blanking formula scaling factor */ 574 #define GTF_D_C_PRIME ((((GTF_D_C - GTF_D_J) * GTF_D_K) / 256) + GTF_D_J) 575 #define GTF_D_M_PRIME ((GTF_D_K * GTF_D_M) / 256) 576 577 /* Secondary */ 578 #define GTF_S_M 3600 /* blanking formula gradient */ 579 #define GTF_S_C 40 /* blanking formula offset */ 580 #define GTF_S_K 128 /* blanking formula scaling factor */ 581 #define GTF_S_J 35 /* blanking formula scaling factor */ 582 #define GTF_S_C_PRIME ((((GTF_S_C - GTF_S_J) * GTF_S_K) / 256) + GTF_S_J) 583 #define GTF_S_M_PRIME ((GTF_S_K * GTF_S_M) / 256) 584 585 /** v4l2_detect_gtf - detect if the given timings follow the GTF standard 586 * @frame_height - the total height of the frame (including blanking) in lines. 587 * @hfreq - the horizontal frequency in Hz. 588 * @vsync - the height of the vertical sync in lines. 589 * @polarities - the horizontal and vertical polarities (same as struct 590 * v4l2_bt_timings polarities). 591 * @interlaced - if this flag is true, it indicates interlaced format 592 * @aspect - preferred aspect ratio. GTF has no method of determining the 593 * aspect ratio in order to derive the image width from the 594 * image height, so it has to be passed explicitly. Usually 595 * the native screen aspect ratio is used for this. If it 596 * is not filled in correctly, then 16:9 will be assumed. 597 * @fmt - the resulting timings. 598 * 599 * This function will attempt to detect if the given values correspond to a 600 * valid GTF format. If so, then it will return true, and fmt will be filled 601 * in with the found GTF timings. 602 */ 603 bool v4l2_detect_gtf(unsigned frame_height, 604 unsigned hfreq, 605 unsigned vsync, 606 u32 polarities, 607 bool interlaced, 608 struct v4l2_fract aspect, 609 struct v4l2_dv_timings *fmt) 610 { 611 int pix_clk; 612 int v_fp, v_bp, h_fp, hsync; 613 int frame_width, image_height, image_width; 614 bool default_gtf; 615 int h_blank; 616 617 if (vsync != 3) 618 return false; 619 620 if (polarities == V4L2_DV_VSYNC_POS_POL) 621 default_gtf = true; 622 else if (polarities == V4L2_DV_HSYNC_POS_POL) 623 default_gtf = false; 624 else 625 return false; 626 627 if (hfreq == 0) 628 return false; 629 630 /* Vertical */ 631 v_fp = GTF_V_FP; 632 v_bp = (GTF_MIN_VSYNC_BP * hfreq + 500000) / 1000000 - vsync; 633 if (interlaced) 634 image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1; 635 else 636 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1; 637 638 if (image_height < 0) 639 return false; 640 641 if (aspect.numerator == 0 || aspect.denominator == 0) { 642 aspect.numerator = 16; 643 aspect.denominator = 9; 644 } 645 image_width = ((image_height * aspect.numerator) / aspect.denominator); 646 image_width = (image_width + GTF_CELL_GRAN/2) & ~(GTF_CELL_GRAN - 1); 647 648 /* Horizontal */ 649 if (default_gtf) { 650 u64 num; 651 u32 den; 652 653 num = ((image_width * GTF_D_C_PRIME * (u64)hfreq) - 654 ((u64)image_width * GTF_D_M_PRIME * 1000)); 655 den = (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) * 656 (2 * GTF_CELL_GRAN); 657 h_blank = div_u64((num + (den >> 1)), den); 658 h_blank *= (2 * GTF_CELL_GRAN); 659 } else { 660 u64 num; 661 u32 den; 662 663 num = ((image_width * GTF_S_C_PRIME * (u64)hfreq) - 664 ((u64)image_width * GTF_S_M_PRIME * 1000)); 665 den = (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) * 666 (2 * GTF_CELL_GRAN); 667 h_blank = div_u64((num + (den >> 1)), den); 668 h_blank *= (2 * GTF_CELL_GRAN); 669 } 670 671 frame_width = image_width + h_blank; 672 673 pix_clk = (image_width + h_blank) * hfreq; 674 pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN; 675 676 hsync = (frame_width * 8 + 50) / 100; 677 hsync = ((hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN) * GTF_CELL_GRAN; 678 679 h_fp = h_blank / 2 - hsync; 680 681 fmt->type = V4L2_DV_BT_656_1120; 682 fmt->bt.polarities = polarities; 683 fmt->bt.width = image_width; 684 fmt->bt.height = image_height; 685 fmt->bt.hfrontporch = h_fp; 686 fmt->bt.vfrontporch = v_fp; 687 fmt->bt.hsync = hsync; 688 fmt->bt.vsync = vsync; 689 fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync; 690 691 if (!interlaced) { 692 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync; 693 fmt->bt.interlaced = V4L2_DV_PROGRESSIVE; 694 } else { 695 fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp - 696 2 * vsync) / 2; 697 fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp - 698 2 * vsync - fmt->bt.vbackporch; 699 fmt->bt.il_vfrontporch = v_fp; 700 fmt->bt.il_vsync = vsync; 701 fmt->bt.flags |= V4L2_DV_FL_HALF_LINE; 702 fmt->bt.interlaced = V4L2_DV_INTERLACED; 703 } 704 705 fmt->bt.pixelclock = pix_clk; 706 fmt->bt.standards = V4L2_DV_BT_STD_GTF; 707 708 if (!default_gtf) 709 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING; 710 711 return true; 712 } 713 EXPORT_SYMBOL_GPL(v4l2_detect_gtf); 714 715 /** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes 716 * 0x15 and 0x16 from the EDID. 717 * @hor_landscape - byte 0x15 from the EDID. 718 * @vert_portrait - byte 0x16 from the EDID. 719 * 720 * Determines the aspect ratio from the EDID. 721 * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2: 722 * "Horizontal and Vertical Screen Size or Aspect Ratio" 723 */ 724 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait) 725 { 726 struct v4l2_fract aspect = { 16, 9 }; 727 u8 ratio; 728 729 /* Nothing filled in, fallback to 16:9 */ 730 if (!hor_landscape && !vert_portrait) 731 return aspect; 732 /* Both filled in, so they are interpreted as the screen size in cm */ 733 if (hor_landscape && vert_portrait) { 734 aspect.numerator = hor_landscape; 735 aspect.denominator = vert_portrait; 736 return aspect; 737 } 738 /* Only one is filled in, so interpret them as a ratio: 739 (val + 99) / 100 */ 740 ratio = hor_landscape | vert_portrait; 741 /* Change some rounded values into the exact aspect ratio */ 742 if (ratio == 79) { 743 aspect.numerator = 16; 744 aspect.denominator = 9; 745 } else if (ratio == 34) { 746 aspect.numerator = 4; 747 aspect.denominator = 3; 748 } else if (ratio == 68) { 749 aspect.numerator = 15; 750 aspect.denominator = 9; 751 } else { 752 aspect.numerator = hor_landscape + 99; 753 aspect.denominator = 100; 754 } 755 if (hor_landscape) 756 return aspect; 757 /* The aspect ratio is for portrait, so swap numerator and denominator */ 758 swap(aspect.denominator, aspect.numerator); 759 return aspect; 760 } 761 EXPORT_SYMBOL_GPL(v4l2_calc_aspect_ratio); 762