drivers/media/v4l2-core/v4l2-dv-timings.c

   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/rational.h>
  26 #include <linux/videodev2.h>
  27 #include <linux/v4l2-dv-timings.h>
  28 #include <media/v4l2-dv-timings.h>
  29 #include <linux/math64.h>
  30
  31 MODULE_AUTHOR("Hans Verkuil");
  32 MODULE_DESCRIPTION("V4L2 DV Timings Helper Functions");
  33 MODULE_LICENSE("GPL");
  34
  35 const struct v4l2_dv_timings v4l2_dv_timings_presets[] = {
  36         V4L2_DV_BT_CEA_640X480P59_94,
  37         V4L2_DV_BT_CEA_720X480I59_94,
  38         V4L2_DV_BT_CEA_720X480P59_94,
  39         V4L2_DV_BT_CEA_720X576I50,
  40         V4L2_DV_BT_CEA_720X576P50,
  41         V4L2_DV_BT_CEA_1280X720P24,
  42         V4L2_DV_BT_CEA_1280X720P25,
  43         V4L2_DV_BT_CEA_1280X720P30,
  44         V4L2_DV_BT_CEA_1280X720P50,
  45         V4L2_DV_BT_CEA_1280X720P60,
  46         V4L2_DV_BT_CEA_1920X1080P24,
  47         V4L2_DV_BT_CEA_1920X1080P25,
  48         V4L2_DV_BT_CEA_1920X1080P30,
  49         V4L2_DV_BT_CEA_1920X1080I50,
  50         V4L2_DV_BT_CEA_1920X1080P50,
  51         V4L2_DV_BT_CEA_1920X1080I60,
  52         V4L2_DV_BT_CEA_1920X1080P60,
  53         V4L2_DV_BT_DMT_640X350P85,
  54         V4L2_DV_BT_DMT_640X400P85,
  55         V4L2_DV_BT_DMT_720X400P85,
  56         V4L2_DV_BT_DMT_640X480P72,
  57         V4L2_DV_BT_DMT_640X480P75,
  58         V4L2_DV_BT_DMT_640X480P85,
  59         V4L2_DV_BT_DMT_800X600P56,
  60         V4L2_DV_BT_DMT_800X600P60,
  61         V4L2_DV_BT_DMT_800X600P72,
  62         V4L2_DV_BT_DMT_800X600P75,
  63         V4L2_DV_BT_DMT_800X600P85,
  64         V4L2_DV_BT_DMT_800X600P120_RB,
  65         V4L2_DV_BT_DMT_848X480P60,
  66         V4L2_DV_BT_DMT_1024X768I43,
  67         V4L2_DV_BT_DMT_1024X768P60,
  68         V4L2_DV_BT_DMT_1024X768P70,
  69         V4L2_DV_BT_DMT_1024X768P75,
  70         V4L2_DV_BT_DMT_1024X768P85,
  71         V4L2_DV_BT_DMT_1024X768P120_RB,
  72         V4L2_DV_BT_DMT_1152X864P75,
  73         V4L2_DV_BT_DMT_1280X768P60_RB,
  74         V4L2_DV_BT_DMT_1280X768P60,
  75         V4L2_DV_BT_DMT_1280X768P75,
  76         V4L2_DV_BT_DMT_1280X768P85,
  77         V4L2_DV_BT_DMT_1280X768P120_RB,
  78         V4L2_DV_BT_DMT_1280X800P60_RB,
  79         V4L2_DV_BT_DMT_1280X800P60,
  80         V4L2_DV_BT_DMT_1280X800P75,
  81         V4L2_DV_BT_DMT_1280X800P85,
  82         V4L2_DV_BT_DMT_1280X800P120_RB,
  83         V4L2_DV_BT_DMT_1280X960P60,
  84         V4L2_DV_BT_DMT_1280X960P85,
  85         V4L2_DV_BT_DMT_1280X960P120_RB,
  86         V4L2_DV_BT_DMT_1280X1024P60,
  87         V4L2_DV_BT_DMT_1280X1024P75,
  88         V4L2_DV_BT_DMT_1280X1024P85,
  89         V4L2_DV_BT_DMT_1280X1024P120_RB,
  90         V4L2_DV_BT_DMT_1360X768P60,
  91         V4L2_DV_BT_DMT_1360X768P120_RB,
  92         V4L2_DV_BT_DMT_1366X768P60,
  93         V4L2_DV_BT_DMT_1366X768P60_RB,
  94         V4L2_DV_BT_DMT_1400X1050P60_RB,
  95         V4L2_DV_BT_DMT_1400X1050P60,
  96         V4L2_DV_BT_DMT_1400X1050P75,
  97         V4L2_DV_BT_DMT_1400X1050P85,
  98         V4L2_DV_BT_DMT_1400X1050P120_RB,
  99         V4L2_DV_BT_DMT_1440X900P60_RB,
 100         V4L2_DV_BT_DMT_1440X900P60,
 101         V4L2_DV_BT_DMT_1440X900P75,
 102         V4L2_DV_BT_DMT_1440X900P85,
 103         V4L2_DV_BT_DMT_1440X900P120_RB,
 104         V4L2_DV_BT_DMT_1600X900P60_RB,
 105         V4L2_DV_BT_DMT_1600X1200P60,
 106         V4L2_DV_BT_DMT_1600X1200P65,
 107         V4L2_DV_BT_DMT_1600X1200P70,
 108         V4L2_DV_BT_DMT_1600X1200P75,
 109         V4L2_DV_BT_DMT_1600X1200P85,
 110         V4L2_DV_BT_DMT_1600X1200P120_RB,
 111         V4L2_DV_BT_DMT_1680X1050P60_RB,
 112         V4L2_DV_BT_DMT_1680X1050P60,
 113         V4L2_DV_BT_DMT_1680X1050P75,
 114         V4L2_DV_BT_DMT_1680X1050P85,
 115         V4L2_DV_BT_DMT_1680X1050P120_RB,
 116         V4L2_DV_BT_DMT_1792X1344P60,
 117         V4L2_DV_BT_DMT_1792X1344P75,
 118         V4L2_DV_BT_DMT_1792X1344P120_RB,
 119         V4L2_DV_BT_DMT_1856X1392P60,
 120         V4L2_DV_BT_DMT_1856X1392P75,
 121         V4L2_DV_BT_DMT_1856X1392P120_RB,
 122         V4L2_DV_BT_DMT_1920X1200P60_RB,
 123         V4L2_DV_BT_DMT_1920X1200P60,
 124         V4L2_DV_BT_DMT_1920X1200P75,
 125         V4L2_DV_BT_DMT_1920X1200P85,
 126         V4L2_DV_BT_DMT_1920X1200P120_RB,
 127         V4L2_DV_BT_DMT_1920X1440P60,
 128         V4L2_DV_BT_DMT_1920X1440P75,
 129         V4L2_DV_BT_DMT_1920X1440P120_RB,
 130         V4L2_DV_BT_DMT_2048X1152P60_RB,
 131         V4L2_DV_BT_DMT_2560X1600P60_RB,
 132         V4L2_DV_BT_DMT_2560X1600P60,
 133         V4L2_DV_BT_DMT_2560X1600P75,
 134         V4L2_DV_BT_DMT_2560X1600P85,
 135         V4L2_DV_BT_DMT_2560X1600P120_RB,
 136         V4L2_DV_BT_CEA_3840X2160P24,
 137         V4L2_DV_BT_CEA_3840X2160P25,
 138         V4L2_DV_BT_CEA_3840X2160P30,
 139         V4L2_DV_BT_CEA_3840X2160P50,
 140         V4L2_DV_BT_CEA_3840X2160P60,
 141         V4L2_DV_BT_CEA_4096X2160P24,
 142         V4L2_DV_BT_CEA_4096X2160P25,
 143         V4L2_DV_BT_CEA_4096X2160P30,
 144         V4L2_DV_BT_CEA_4096X2160P50,
 145         V4L2_DV_BT_DMT_4096X2160P59_94_RB,
 146         V4L2_DV_BT_CEA_4096X2160P60,
 147         { }
 148 };
 149 EXPORT_SYMBOL_GPL(v4l2_dv_timings_presets);
 150
 151 bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
 152                            const struct v4l2_dv_timings_cap *dvcap,
 153                            v4l2_check_dv_timings_fnc fnc,
 154                            void *fnc_handle)
 155 {
 156         const struct v4l2_bt_timings *bt = &t->bt;
 157         const struct v4l2_bt_timings_cap *cap = &dvcap->bt;
 158         u32 caps = cap->capabilities;
 159         const u32 max_vert = 10240;
 160         u32 max_hor = 3 * bt->width;
 161
 162         if (t->type != V4L2_DV_BT_656_1120)
 163                 return false;
 164         if (t->type != dvcap->type ||
 165             bt->height < cap->min_height ||
 166             bt->height > cap->max_height ||
 167             bt->width < cap->min_width ||
 168             bt->width > cap->max_width ||
 169             bt->pixelclock < cap->min_pixelclock ||
 170             bt->pixelclock > cap->max_pixelclock ||
 171             (!(caps & V4L2_DV_BT_CAP_CUSTOM) &&
 172              cap->standards && bt->standards &&
 173              !(bt->standards & cap->standards)) ||
 174             (bt->interlaced && !(caps & V4L2_DV_BT_CAP_INTERLACED)) ||
 175             (!bt->interlaced && !(caps & V4L2_DV_BT_CAP_PROGRESSIVE)))
 176                 return false;
 177
 178         /* sanity checks for the blanking timings */
 179         if (!bt->interlaced &&
 180             (bt->il_vbackporch || bt->il_vsync || bt->il_vfrontporch))
 181                 return false;
 182         /*
 183          * Some video receivers cannot properly separate the frontporch,
 184          * backporch and sync values, and instead they only have the total
 185          * blanking. That can be assigned to any of these three fields.
 186          * So just check that none of these are way out of range.
 187          */
 188         if (bt->hfrontporch > max_hor ||
 189             bt->hsync > max_hor || bt->hbackporch > max_hor)
 190                 return false;
 191         if (bt->vfrontporch > max_vert ||
 192             bt->vsync > max_vert || bt->vbackporch > max_vert)
 193                 return false;
 194         if (bt->interlaced && (bt->il_vfrontporch > max_vert ||
 195             bt->il_vsync > max_vert || bt->il_vbackporch > max_vert))
 196                 return false;
 197         return fnc == NULL || fnc(t, fnc_handle);
 198 }
 199 EXPORT_SYMBOL_GPL(v4l2_valid_dv_timings);
 200
 201 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t,
 202                              const struct v4l2_dv_timings_cap *cap,
 203                              v4l2_check_dv_timings_fnc fnc,
 204                              void *fnc_handle)
 205 {
 206         u32 i, idx;
 207
 208         memset(t->reserved, 0, sizeof(t->reserved));
 209         for (i = idx = 0; 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                     idx++ == t->index) {
 213                         t->timings = v4l2_dv_timings_presets[i];
 214                         return 0;
 215                 }
 216         }
 217         return -EINVAL;
 218 }
 219 EXPORT_SYMBOL_GPL(v4l2_enum_dv_timings_cap);
 220
 221 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t,
 222                               const struct v4l2_dv_timings_cap *cap,
 223                               unsigned pclock_delta,
 224                               v4l2_check_dv_timings_fnc fnc,
 225                               void *fnc_handle)
 226 {
 227         int i;
 228
 229         if (!v4l2_valid_dv_timings(t, cap, fnc, fnc_handle))
 230                 return false;
 231
 232         for (i = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
 233                 if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
 234                                           fnc, fnc_handle) &&
 235                     v4l2_match_dv_timings(t, v4l2_dv_timings_presets + i,
 236                                           pclock_delta, false)) {
 237                         u32 flags = t->bt.flags & V4L2_DV_FL_REDUCED_FPS;
 238
 239                         *t = v4l2_dv_timings_presets[i];
 240                         if (can_reduce_fps(&t->bt))
 241                                 t->bt.flags |= flags;
 242
 243                         return true;
 244                 }
 245         }
 246         return false;
 247 }
 248 EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cap);
 249
 250 bool v4l2_find_dv_timings_cea861_vic(struct v4l2_dv_timings *t, u8 vic)
 251 {
 252         unsigned int i;
 253
 254         for (i = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
 255                 const struct v4l2_bt_timings *bt =
 256                         &v4l2_dv_timings_presets[i].bt;
 257
 258                 if ((bt->flags & V4L2_DV_FL_HAS_CEA861_VIC) &&
 259                     bt->cea861_vic == vic) {
 260                         *t = v4l2_dv_timings_presets[i];
 261                         return true;
 262                 }
 263         }
 264         return false;
 265 }
 266 EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cea861_vic);
 267
 268 /**
 269  * v4l2_match_dv_timings - check if two timings match
 270  * @t1 - compare this v4l2_dv_timings struct...
 271  * @t2 - with this struct.
 272  * @pclock_delta - the allowed pixelclock deviation.
 273  * @match_reduced_fps - if true, then fail if V4L2_DV_FL_REDUCED_FPS does not
 274  * match.
 275  *
 276  * Compare t1 with t2 with a given margin of error for the pixelclock.
 277  */
 278 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *t1,
 279                            const struct v4l2_dv_timings *t2,
 280                            unsigned pclock_delta, bool match_reduced_fps)
 281 {
 282         if (t1->type != t2->type || t1->type != V4L2_DV_BT_656_1120)
 283                 return false;
 284         if (t1->bt.width == t2->bt.width &&
 285             t1->bt.height == t2->bt.height &&
 286             t1->bt.interlaced == t2->bt.interlaced &&
 287             t1->bt.polarities == t2->bt.polarities &&
 288             t1->bt.pixelclock >= t2->bt.pixelclock - pclock_delta &&
 289             t1->bt.pixelclock <= t2->bt.pixelclock + pclock_delta &&
 290             t1->bt.hfrontporch == t2->bt.hfrontporch &&
 291             t1->bt.hsync == t2->bt.hsync &&
 292             t1->bt.hbackporch == t2->bt.hbackporch &&
 293             t1->bt.vfrontporch == t2->bt.vfrontporch &&
 294             t1->bt.vsync == t2->bt.vsync &&
 295             t1->bt.vbackporch == t2->bt.vbackporch &&
 296             (!match_reduced_fps ||
 297              (t1->bt.flags & V4L2_DV_FL_REDUCED_FPS) ==
 298                 (t2->bt.flags & V4L2_DV_FL_REDUCED_FPS)) &&
 299             (!t1->bt.interlaced ||
 300                 (t1->bt.il_vfrontporch == t2->bt.il_vfrontporch &&
 301                  t1->bt.il_vsync == t2->bt.il_vsync &&
 302                  t1->bt.il_vbackporch == t2->bt.il_vbackporch)))
 303                 return true;
 304         return false;
 305 }
 306 EXPORT_SYMBOL_GPL(v4l2_match_dv_timings);
 307
 308 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix,
 309                            const struct v4l2_dv_timings *t, bool detailed)
 310 {
 311         const struct v4l2_bt_timings *bt = &t->bt;
 312         u32 htot, vtot;
 313         u32 fps;
 314
 315         if (t->type != V4L2_DV_BT_656_1120)
 316                 return;
 317
 318         htot = V4L2_DV_BT_FRAME_WIDTH(bt);
 319         vtot = V4L2_DV_BT_FRAME_HEIGHT(bt);
 320         if (bt->interlaced)
 321                 vtot /= 2;
 322
 323         fps = (htot * vtot) > 0 ? div_u64((100 * (u64)bt->pixelclock),
 324                                   (htot * vtot)) : 0;
 325
 326         if (prefix == NULL)
 327                 prefix = "";
 328
 329         pr_info("%s: %s%ux%u%s%u.%u (%ux%u)\n", dev_prefix, prefix,
 330                 bt->width, bt->height, bt->interlaced ? "i" : "p",
 331                 fps / 100, fps % 100, htot, vtot);
 332
 333         if (!detailed)
 334                 return;
 335
 336         pr_info("%s: horizontal: fp = %u, %ssync = %u, bp = %u\n",
 337                         dev_prefix, bt->hfrontporch,
 338                         (bt->polarities & V4L2_DV_HSYNC_POS_POL) ? "+" : "-",
 339                         bt->hsync, bt->hbackporch);
 340         pr_info("%s: vertical: fp = %u, %ssync = %u, bp = %u\n",
 341                         dev_prefix, bt->vfrontporch,
 342                         (bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
 343                         bt->vsync, bt->vbackporch);
 344         if (bt->interlaced)
 345                 pr_info("%s: vertical bottom field: fp = %u, %ssync = %u, bp = %u\n",
 346                         dev_prefix, bt->il_vfrontporch,
 347                         (bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
 348                         bt->il_vsync, bt->il_vbackporch);
 349         pr_info("%s: pixelclock: %llu\n", dev_prefix, bt->pixelclock);
 350         pr_info("%s: flags (0x%x):%s%s%s%s%s%s%s%s%s%s\n",
 351                         dev_prefix, bt->flags,
 352                         (bt->flags & V4L2_DV_FL_REDUCED_BLANKING) ?
 353                         " REDUCED_BLANKING" : "",
 354                         ((bt->flags & V4L2_DV_FL_REDUCED_BLANKING) &&
 355                          bt->vsync == 8) ? " (V2)" : "",
 356                         (bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS) ?
 357                         " CAN_REDUCE_FPS" : "",
 358                         (bt->flags & V4L2_DV_FL_REDUCED_FPS) ?
 359                         " REDUCED_FPS" : "",
 360                         (bt->flags & V4L2_DV_FL_HALF_LINE) ?
 361                         " HALF_LINE" : "",
 362                         (bt->flags & V4L2_DV_FL_IS_CE_VIDEO) ?
 363                         " CE_VIDEO" : "",
 364                         (bt->flags & V4L2_DV_FL_FIRST_FIELD_EXTRA_LINE) ?
 365                         " FIRST_FIELD_EXTRA_LINE" : "",
 366                         (bt->flags & V4L2_DV_FL_HAS_PICTURE_ASPECT) ?
 367                         " HAS_PICTURE_ASPECT" : "",
 368                         (bt->flags & V4L2_DV_FL_HAS_CEA861_VIC) ?
 369                         " HAS_CEA861_VIC" : "",
 370                         (bt->flags & V4L2_DV_FL_HAS_HDMI_VIC) ?
 371                         " HAS_HDMI_VIC" : "");
 372         pr_info("%s: standards (0x%x):%s%s%s%s%s\n", dev_prefix, bt->standards,
 373                         (bt->standards & V4L2_DV_BT_STD_CEA861) ?  " CEA" : "",
 374                         (bt->standards & V4L2_DV_BT_STD_DMT) ?  " DMT" : "",
 375                         (bt->standards & V4L2_DV_BT_STD_CVT) ?  " CVT" : "",
 376                         (bt->standards & V4L2_DV_BT_STD_GTF) ?  " GTF" : "",
 377                         (bt->standards & V4L2_DV_BT_STD_SDI) ?  " SDI" : "");
 378         if (bt->flags & V4L2_DV_FL_HAS_PICTURE_ASPECT)
 379                 pr_info("%s: picture aspect (hor:vert): %u:%u\n", dev_prefix,
 380                         bt->picture_aspect.numerator,
 381                         bt->picture_aspect.denominator);
 382         if (bt->flags & V4L2_DV_FL_HAS_CEA861_VIC)
 383                 pr_info("%s: CEA-861 VIC: %u\n", dev_prefix, bt->cea861_vic);
 384         if (bt->flags & V4L2_DV_FL_HAS_HDMI_VIC)
 385                 pr_info("%s: HDMI VIC: %u\n", dev_prefix, bt->hdmi_vic);
 386 }
 387 EXPORT_SYMBOL_GPL(v4l2_print_dv_timings);
 388
 389 struct v4l2_fract v4l2_dv_timings_aspect_ratio(const struct v4l2_dv_timings *t)
 390 {
 391         struct v4l2_fract ratio = { 1, 1 };
 392         unsigned long n, d;
 393
 394         if (t->type != V4L2_DV_BT_656_1120)
 395                 return ratio;
 396         if (!(t->bt.flags & V4L2_DV_FL_HAS_PICTURE_ASPECT))
 397                 return ratio;
 398
 399         ratio.numerator = t->bt.width * t->bt.picture_aspect.denominator;
 400         ratio.denominator = t->bt.height * t->bt.picture_aspect.numerator;
 401
 402         rational_best_approximation(ratio.numerator, ratio.denominator,
 403                                     ratio.numerator, ratio.denominator, &n, &d);
 404         ratio.numerator = n;
 405         ratio.denominator = d;
 406         return ratio;
 407 }
 408 EXPORT_SYMBOL_GPL(v4l2_dv_timings_aspect_ratio);
 409
 410 /*
 411  * CVT defines
 412  * Based on Coordinated Video Timings Standard
 413  * version 1.1 September 10, 2003
 414  */
 415
 416 #define CVT_PXL_CLK_GRAN        250000  /* pixel clock granularity */
 417 #define CVT_PXL_CLK_GRAN_RB_V2 1000     /* granularity for reduced blanking v2*/
 418
 419 /* Normal blanking */
 420 #define CVT_MIN_V_BPORCH        7       /* lines */
 421 #define CVT_MIN_V_PORCH_RND     3       /* lines */
 422 #define CVT_MIN_VSYNC_BP        550     /* min time of vsync + back porch (us) */
 423 #define CVT_HSYNC_PERCENT       8       /* nominal hsync as percentage of line */
 424
 425 /* Normal blanking for CVT uses GTF to calculate horizontal blanking */
 426 #define CVT_CELL_GRAN           8       /* character cell granularity */
 427 #define CVT_M                   600     /* blanking formula gradient */
 428 #define CVT_C                   40      /* blanking formula offset */
 429 #define CVT_K                   128     /* blanking formula scaling factor */
 430 #define CVT_J                   20      /* blanking formula scaling factor */
 431 #define CVT_C_PRIME (((CVT_C - CVT_J) * CVT_K / 256) + CVT_J)
 432 #define CVT_M_PRIME (CVT_K * CVT_M / 256)
 433
 434 /* Reduced Blanking */
 435 #define CVT_RB_MIN_V_BPORCH    7       /* lines  */
 436 #define CVT_RB_V_FPORCH        3       /* lines  */
 437 #define CVT_RB_MIN_V_BLANK   460       /* us     */
 438 #define CVT_RB_H_SYNC         32       /* pixels */
 439 #define CVT_RB_H_BLANK       160       /* pixels */
 440 /* Reduce blanking Version 2 */
 441 #define CVT_RB_V2_H_BLANK     80       /* pixels */
 442 #define CVT_RB_MIN_V_FPORCH    3       /* lines  */
 443 #define CVT_RB_V2_MIN_V_FPORCH 1       /* lines  */
 444 #define CVT_RB_V_BPORCH        6       /* lines  */
 445
 446 /** v4l2_detect_cvt - detect if the given timings follow the CVT standard
 447  * @frame_height - the total height of the frame (including blanking) in lines.
 448  * @hfreq - the horizontal frequency in Hz.
 449  * @vsync - the height of the vertical sync in lines.
 450  * @active_width - active width of image (does not include blanking). This
 451  * information is needed only in case of version 2 of reduced blanking.
 452  * In other cases, this parameter does not have any effect on timings.
 453  * @polarities - the horizontal and vertical polarities (same as struct
 454  *              v4l2_bt_timings polarities).
 455  * @interlaced - if this flag is true, it indicates interlaced format
 456  * @fmt - the resulting timings.
 457  *
 458  * This function will attempt to detect if the given values correspond to a
 459  * valid CVT format. If so, then it will return true, and fmt will be filled
 460  * in with the found CVT timings.
 461  */
 462 bool v4l2_detect_cvt(unsigned frame_height,
 463                      unsigned hfreq,
 464                      unsigned vsync,
 465                      unsigned active_width,
 466                      u32 polarities,
 467                      bool interlaced,
 468                      struct v4l2_dv_timings *fmt)
 469 {
 470         int  v_fp, v_bp, h_fp, h_bp, hsync;
 471         int  frame_width, image_height, image_width;
 472         bool reduced_blanking;
 473         bool rb_v2 = false;
 474         unsigned pix_clk;
 475
 476         if (vsync < 4 || vsync > 8)
 477                 return false;
 478
 479         if (polarities == V4L2_DV_VSYNC_POS_POL)
 480                 reduced_blanking = false;
 481         else if (polarities == V4L2_DV_HSYNC_POS_POL)
 482                 reduced_blanking = true;
 483         else
 484                 return false;
 485
 486         if (reduced_blanking && vsync == 8)
 487                 rb_v2 = true;
 488
 489         if (rb_v2 && active_width == 0)
 490                 return false;
 491
 492         if (!rb_v2 && vsync > 7)
 493                 return false;
 494
 495         if (hfreq == 0)
 496                 return false;
 497
 498         /* Vertical */
 499         if (reduced_blanking) {
 500                 if (rb_v2) {
 501                         v_bp = CVT_RB_V_BPORCH;
 502                         v_fp = (CVT_RB_MIN_V_BLANK * hfreq) / 1000000 + 1;
 503                         v_fp -= vsync + v_bp;
 504
 505                         if (v_fp < CVT_RB_V2_MIN_V_FPORCH)
 506                                 v_fp = CVT_RB_V2_MIN_V_FPORCH;
 507                 } else {
 508                         v_fp = CVT_RB_V_FPORCH;
 509                         v_bp = (CVT_RB_MIN_V_BLANK * hfreq) / 1000000 + 1;
 510                         v_bp -= vsync + v_fp;
 511
 512                         if (v_bp < CVT_RB_MIN_V_BPORCH)
 513                                 v_bp = CVT_RB_MIN_V_BPORCH;
 514                 }
 515         } else {
 516                 v_fp = CVT_MIN_V_PORCH_RND;
 517                 v_bp = (CVT_MIN_VSYNC_BP * hfreq) / 1000000 + 1 - vsync;
 518
 519                 if (v_bp < CVT_MIN_V_BPORCH)
 520                         v_bp = CVT_MIN_V_BPORCH;
 521         }
 522
 523         if (interlaced)
 524                 image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1;
 525         else
 526                 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
 527
 528         if (image_height < 0)
 529                 return false;
 530
 531         /* Aspect ratio based on vsync */
 532         switch (vsync) {
 533         case 4:
 534                 image_width = (image_height * 4) / 3;
 535                 break;
 536         case 5:
 537                 image_width = (image_height * 16) / 9;
 538                 break;
 539         case 6:
 540                 image_width = (image_height * 16) / 10;
 541                 break;
 542         case 7:
 543                 /* special case */
 544                 if (image_height == 1024)
 545                         image_width = (image_height * 5) / 4;
 546                 else if (image_height == 768)
 547                         image_width = (image_height * 15) / 9;
 548                 else
 549                         return false;
 550                 break;
 551         case 8:
 552                 image_width = active_width;
 553                 break;
 554         default:
 555                 return false;
 556         }
 557
 558         if (!rb_v2)
 559                 image_width = image_width & ~7;
 560
 561         /* Horizontal */
 562         if (reduced_blanking) {
 563                 int h_blank;
 564                 int clk_gran;
 565
 566                 h_blank = rb_v2 ? CVT_RB_V2_H_BLANK : CVT_RB_H_BLANK;
 567                 clk_gran = rb_v2 ? CVT_PXL_CLK_GRAN_RB_V2 : CVT_PXL_CLK_GRAN;
 568
 569                 pix_clk = (image_width + h_blank) * hfreq;
 570                 pix_clk = (pix_clk / clk_gran) * clk_gran;
 571
 572                 h_bp  = h_blank / 2;
 573                 hsync = CVT_RB_H_SYNC;
 574                 h_fp  = h_blank - h_bp - hsync;
 575
 576                 frame_width = image_width + h_blank;
 577         } else {
 578                 unsigned ideal_duty_cycle_per_myriad =
 579                         100 * CVT_C_PRIME - (CVT_M_PRIME * 100000) / hfreq;
 580                 int h_blank;
 581
 582                 if (ideal_duty_cycle_per_myriad < 2000)
 583                         ideal_duty_cycle_per_myriad = 2000;
 584
 585                 h_blank = image_width * ideal_duty_cycle_per_myriad /
 586                                         (10000 - ideal_duty_cycle_per_myriad);
 587                 h_blank = (h_blank / (2 * CVT_CELL_GRAN)) * 2 * CVT_CELL_GRAN;
 588
 589                 pix_clk = (image_width + h_blank) * hfreq;
 590                 pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
 591
 592                 h_bp = h_blank / 2;
 593                 frame_width = image_width + h_blank;
 594
 595                 hsync = frame_width * CVT_HSYNC_PERCENT / 100;
 596                 hsync = (hsync / CVT_CELL_GRAN) * CVT_CELL_GRAN;
 597                 h_fp = h_blank - hsync - h_bp;
 598         }
 599
 600         fmt->type = V4L2_DV_BT_656_1120;
 601         fmt->bt.polarities = polarities;
 602         fmt->bt.width = image_width;
 603         fmt->bt.height = image_height;
 604         fmt->bt.hfrontporch = h_fp;
 605         fmt->bt.vfrontporch = v_fp;
 606         fmt->bt.hsync = hsync;
 607         fmt->bt.vsync = vsync;
 608         fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
 609
 610         if (!interlaced) {
 611                 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
 612                 fmt->bt.interlaced = V4L2_DV_PROGRESSIVE;
 613         } else {
 614                 fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp -
 615                                       2 * vsync) / 2;
 616                 fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp -
 617                                         2 * vsync - fmt->bt.vbackporch;
 618                 fmt->bt.il_vfrontporch = v_fp;
 619                 fmt->bt.il_vsync = vsync;
 620                 fmt->bt.flags |= V4L2_DV_FL_HALF_LINE;
 621                 fmt->bt.interlaced = V4L2_DV_INTERLACED;
 622         }
 623
 624         fmt->bt.pixelclock = pix_clk;
 625         fmt->bt.standards = V4L2_DV_BT_STD_CVT;
 626
 627         if (reduced_blanking)
 628                 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
 629
 630         return true;
 631 }
 632 EXPORT_SYMBOL_GPL(v4l2_detect_cvt);
 633
 634 /*
 635  * GTF defines
 636  * Based on Generalized Timing Formula Standard
 637  * Version 1.1 September 2, 1999
 638  */
 639
 640 #define GTF_PXL_CLK_GRAN        250000  /* pixel clock granularity */
 641
 642 #define GTF_MIN_VSYNC_BP        550     /* min time of vsync + back porch (us) */
 643 #define GTF_V_FP                1       /* vertical front porch (lines) */
 644 #define GTF_CELL_GRAN           8       /* character cell granularity */
 645
 646 /* Default */
 647 #define GTF_D_M                 600     /* blanking formula gradient */
 648 #define GTF_D_C                 40      /* blanking formula offset */
 649 #define GTF_D_K                 128     /* blanking formula scaling factor */
 650 #define GTF_D_J                 20      /* blanking formula scaling factor */
 651 #define GTF_D_C_PRIME ((((GTF_D_C - GTF_D_J) * GTF_D_K) / 256) + GTF_D_J)
 652 #define GTF_D_M_PRIME ((GTF_D_K * GTF_D_M) / 256)
 653
 654 /* Secondary */
 655 #define GTF_S_M                 3600    /* blanking formula gradient */
 656 #define GTF_S_C                 40      /* blanking formula offset */
 657 #define GTF_S_K                 128     /* blanking formula scaling factor */
 658 #define GTF_S_J                 35      /* blanking formula scaling factor */
 659 #define GTF_S_C_PRIME ((((GTF_S_C - GTF_S_J) * GTF_S_K) / 256) + GTF_S_J)
 660 #define GTF_S_M_PRIME ((GTF_S_K * GTF_S_M) / 256)
 661
 662 /** v4l2_detect_gtf - detect if the given timings follow the GTF standard
 663  * @frame_height - the total height of the frame (including blanking) in lines.
 664  * @hfreq - the horizontal frequency in Hz.
 665  * @vsync - the height of the vertical sync in lines.
 666  * @polarities - the horizontal and vertical polarities (same as struct
 667  *              v4l2_bt_timings polarities).
 668  * @interlaced - if this flag is true, it indicates interlaced format
 669  * @aspect - preferred aspect ratio. GTF has no method of determining the
 670  *              aspect ratio in order to derive the image width from the
 671  *              image height, so it has to be passed explicitly. Usually
 672  *              the native screen aspect ratio is used for this. If it
 673  *              is not filled in correctly, then 16:9 will be assumed.
 674  * @fmt - the resulting timings.
 675  *
 676  * This function will attempt to detect if the given values correspond to a
 677  * valid GTF format. If so, then it will return true, and fmt will be filled
 678  * in with the found GTF timings.
 679  */
 680 bool v4l2_detect_gtf(unsigned frame_height,
 681                 unsigned hfreq,
 682                 unsigned vsync,
 683                 u32 polarities,
 684                 bool interlaced,
 685                 struct v4l2_fract aspect,
 686                 struct v4l2_dv_timings *fmt)
 687 {
 688         int pix_clk;
 689         int  v_fp, v_bp, h_fp, hsync;
 690         int frame_width, image_height, image_width;
 691         bool default_gtf;
 692         int h_blank;
 693
 694         if (vsync != 3)
 695                 return false;
 696
 697         if (polarities == V4L2_DV_VSYNC_POS_POL)
 698                 default_gtf = true;
 699         else if (polarities == V4L2_DV_HSYNC_POS_POL)
 700                 default_gtf = false;
 701         else
 702                 return false;
 703
 704         if (hfreq == 0)
 705                 return false;
 706
 707         /* Vertical */
 708         v_fp = GTF_V_FP;
 709         v_bp = (GTF_MIN_VSYNC_BP * hfreq + 500000) / 1000000 - vsync;
 710         if (interlaced)
 711                 image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1;
 712         else
 713                 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
 714
 715         if (image_height < 0)
 716                 return false;
 717
 718         if (aspect.numerator == 0 || aspect.denominator == 0) {
 719                 aspect.numerator = 16;
 720                 aspect.denominator = 9;
 721         }
 722         image_width = ((image_height * aspect.numerator) / aspect.denominator);
 723         image_width = (image_width + GTF_CELL_GRAN/2) & ~(GTF_CELL_GRAN - 1);
 724
 725         /* Horizontal */
 726         if (default_gtf) {
 727                 u64 num;
 728                 u32 den;
 729
 730                 num = ((image_width * GTF_D_C_PRIME * (u64)hfreq) -
 731                       ((u64)image_width * GTF_D_M_PRIME * 1000));
 732                 den = (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) *
 733                       (2 * GTF_CELL_GRAN);
 734                 h_blank = div_u64((num + (den >> 1)), den);
 735                 h_blank *= (2 * GTF_CELL_GRAN);
 736         } else {
 737                 u64 num;
 738                 u32 den;
 739
 740                 num = ((image_width * GTF_S_C_PRIME * (u64)hfreq) -
 741                       ((u64)image_width * GTF_S_M_PRIME * 1000));
 742                 den = (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) *
 743                       (2 * GTF_CELL_GRAN);
 744                 h_blank = div_u64((num + (den >> 1)), den);
 745                 h_blank *= (2 * GTF_CELL_GRAN);
 746         }
 747
 748         frame_width = image_width + h_blank;
 749
 750         pix_clk = (image_width + h_blank) * hfreq;
 751         pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN;
 752
 753         hsync = (frame_width * 8 + 50) / 100;
 754         hsync = ((hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN) * GTF_CELL_GRAN;
 755
 756         h_fp = h_blank / 2 - hsync;
 757
 758         fmt->type = V4L2_DV_BT_656_1120;
 759         fmt->bt.polarities = polarities;
 760         fmt->bt.width = image_width;
 761         fmt->bt.height = image_height;
 762         fmt->bt.hfrontporch = h_fp;
 763         fmt->bt.vfrontporch = v_fp;
 764         fmt->bt.hsync = hsync;
 765         fmt->bt.vsync = vsync;
 766         fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
 767
 768         if (!interlaced) {
 769                 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
 770                 fmt->bt.interlaced = V4L2_DV_PROGRESSIVE;
 771         } else {
 772                 fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp -
 773                                       2 * vsync) / 2;
 774                 fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp -
 775                                         2 * vsync - fmt->bt.vbackporch;
 776                 fmt->bt.il_vfrontporch = v_fp;
 777                 fmt->bt.il_vsync = vsync;
 778                 fmt->bt.flags |= V4L2_DV_FL_HALF_LINE;
 779                 fmt->bt.interlaced = V4L2_DV_INTERLACED;
 780         }
 781
 782         fmt->bt.pixelclock = pix_clk;
 783         fmt->bt.standards = V4L2_DV_BT_STD_GTF;
 784
 785         if (!default_gtf)
 786                 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
 787
 788         return true;
 789 }
 790 EXPORT_SYMBOL_GPL(v4l2_detect_gtf);
 791
 792 /** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
 793  *      0x15 and 0x16 from the EDID.
 794  * @hor_landscape - byte 0x15 from the EDID.
 795  * @vert_portrait - byte 0x16 from the EDID.
 796  *
 797  * Determines the aspect ratio from the EDID.
 798  * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
 799  * "Horizontal and Vertical Screen Size or Aspect Ratio"
 800  */
 801 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait)
 802 {
 803         struct v4l2_fract aspect = { 16, 9 };
 804         u8 ratio;
 805
 806         /* Nothing filled in, fallback to 16:9 */
 807         if (!hor_landscape && !vert_portrait)
 808                 return aspect;
 809         /* Both filled in, so they are interpreted as the screen size in cm */
 810         if (hor_landscape && vert_portrait) {
 811                 aspect.numerator = hor_landscape;
 812                 aspect.denominator = vert_portrait;
 813                 return aspect;
 814         }
 815         /* Only one is filled in, so interpret them as a ratio:
 816            (val + 99) / 100 */
 817         ratio = hor_landscape | vert_portrait;
 818         /* Change some rounded values into the exact aspect ratio */
 819         if (ratio == 79) {
 820                 aspect.numerator = 16;
 821                 aspect.denominator = 9;
 822         } else if (ratio == 34) {
 823                 aspect.numerator = 4;
 824                 aspect.denominator = 3;
 825         } else if (ratio == 68) {
 826                 aspect.numerator = 15;
 827                 aspect.denominator = 9;
 828         } else {
 829                 aspect.numerator = hor_landscape + 99;
 830                 aspect.denominator = 100;
 831         }
 832         if (hor_landscape)
 833                 return aspect;
 834         /* The aspect ratio is for portrait, so swap numerator and denominator */
 835         swap(aspect.denominator, aspect.numerator);
 836         return aspect;
 837 }
 838 EXPORT_SYMBOL_GPL(v4l2_calc_aspect_ratio);