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Merge tag 'iommu-fixes-v4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/joro...
[deliverable/linux.git] / 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/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 (cap->standards && bt->standards &&
169 !(bt->standards & cap->standards)) ||
170 (bt->interlaced && !(caps & V4L2_DV_BT_CAP_INTERLACED)) ||
171 (!bt->interlaced && !(caps & V4L2_DV_BT_CAP_PROGRESSIVE)))
172 return false;
173 return fnc == NULL || fnc(t, fnc_handle);
174 }
175 EXPORT_SYMBOL_GPL(v4l2_valid_dv_timings);
176
177 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t,
178 const struct v4l2_dv_timings_cap *cap,
179 v4l2_check_dv_timings_fnc fnc,
180 void *fnc_handle)
181 {
182 u32 i, idx;
183
184 memset(t->reserved, 0, sizeof(t->reserved));
185 for (i = idx = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
186 if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
187 fnc, fnc_handle) &&
188 idx++ == t->index) {
189 t->timings = v4l2_dv_timings_presets[i];
190 return 0;
191 }
192 }
193 return -EINVAL;
194 }
195 EXPORT_SYMBOL_GPL(v4l2_enum_dv_timings_cap);
196
197 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t,
198 const struct v4l2_dv_timings_cap *cap,
199 unsigned pclock_delta,
200 v4l2_check_dv_timings_fnc fnc,
201 void *fnc_handle)
202 {
203 int i;
204
205 if (!v4l2_valid_dv_timings(t, cap, fnc, fnc_handle))
206 return false;
207
208 for (i = 0; i < v4l2_dv_timings_presets[i].bt.width; i++) {
209 if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
210 fnc, fnc_handle) &&
211 v4l2_match_dv_timings(t, v4l2_dv_timings_presets + i,
212 pclock_delta)) {
213 *t = v4l2_dv_timings_presets[i];
214 return true;
215 }
216 }
217 return false;
218 }
219 EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cap);
220
221 /**
222 * v4l2_match_dv_timings - check if two timings match
223 * @t1 - compare this v4l2_dv_timings struct...
224 * @t2 - with this struct.
225 * @pclock_delta - the allowed pixelclock deviation.
226 *
227 * Compare t1 with t2 with a given margin of error for the pixelclock.
228 */
229 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *t1,
230 const struct v4l2_dv_timings *t2,
231 unsigned pclock_delta)
232 {
233 if (t1->type != t2->type || t1->type != V4L2_DV_BT_656_1120)
234 return false;
235 if (t1->bt.width == t2->bt.width &&
236 t1->bt.height == t2->bt.height &&
237 t1->bt.interlaced == t2->bt.interlaced &&
238 t1->bt.polarities == t2->bt.polarities &&
239 t1->bt.pixelclock >= t2->bt.pixelclock - pclock_delta &&
240 t1->bt.pixelclock <= t2->bt.pixelclock + pclock_delta &&
241 t1->bt.hfrontporch == t2->bt.hfrontporch &&
242 t1->bt.vfrontporch == t2->bt.vfrontporch &&
243 t1->bt.vsync == t2->bt.vsync &&
244 t1->bt.vbackporch == t2->bt.vbackporch &&
245 (!t1->bt.interlaced ||
246 (t1->bt.il_vfrontporch == t2->bt.il_vfrontporch &&
247 t1->bt.il_vsync == t2->bt.il_vsync &&
248 t1->bt.il_vbackporch == t2->bt.il_vbackporch)))
249 return true;
250 return false;
251 }
252 EXPORT_SYMBOL_GPL(v4l2_match_dv_timings);
253
254 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix,
255 const struct v4l2_dv_timings *t, bool detailed)
256 {
257 const struct v4l2_bt_timings *bt = &t->bt;
258 u32 htot, vtot;
259
260 if (t->type != V4L2_DV_BT_656_1120)
261 return;
262
263 htot = V4L2_DV_BT_FRAME_WIDTH(bt);
264 vtot = V4L2_DV_BT_FRAME_HEIGHT(bt);
265 if (bt->interlaced)
266 vtot /= 2;
267
268 if (prefix == NULL)
269 prefix = "";
270
271 pr_info("%s: %s%ux%u%s%u (%ux%u)\n", dev_prefix, prefix,
272 bt->width, bt->height, bt->interlaced ? "i" : "p",
273 (htot * vtot) > 0 ? ((u32)bt->pixelclock / (htot * vtot)) : 0,
274 htot, vtot);
275
276 if (!detailed)
277 return;
278
279 pr_info("%s: horizontal: fp = %u, %ssync = %u, bp = %u\n",
280 dev_prefix, bt->hfrontporch,
281 (bt->polarities & V4L2_DV_HSYNC_POS_POL) ? "+" : "-",
282 bt->hsync, bt->hbackporch);
283 pr_info("%s: vertical: fp = %u, %ssync = %u, bp = %u\n",
284 dev_prefix, bt->vfrontporch,
285 (bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
286 bt->vsync, bt->vbackporch);
287 if (bt->interlaced)
288 pr_info("%s: vertical bottom field: fp = %u, %ssync = %u, bp = %u\n",
289 dev_prefix, bt->il_vfrontporch,
290 (bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
291 bt->il_vsync, bt->il_vbackporch);
292 pr_info("%s: pixelclock: %llu\n", dev_prefix, bt->pixelclock);
293 pr_info("%s: flags (0x%x):%s%s%s%s%s\n", dev_prefix, bt->flags,
294 (bt->flags & V4L2_DV_FL_REDUCED_BLANKING) ?
295 " REDUCED_BLANKING" : "",
296 (bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS) ?
297 " CAN_REDUCE_FPS" : "",
298 (bt->flags & V4L2_DV_FL_REDUCED_FPS) ?
299 " REDUCED_FPS" : "",
300 (bt->flags & V4L2_DV_FL_HALF_LINE) ?
301 " HALF_LINE" : "",
302 (bt->flags & V4L2_DV_FL_IS_CE_VIDEO) ?
303 " CE_VIDEO" : "");
304 pr_info("%s: standards (0x%x):%s%s%s%s\n", dev_prefix, bt->standards,
305 (bt->standards & V4L2_DV_BT_STD_CEA861) ? " CEA" : "",
306 (bt->standards & V4L2_DV_BT_STD_DMT) ? " DMT" : "",
307 (bt->standards & V4L2_DV_BT_STD_CVT) ? " CVT" : "",
308 (bt->standards & V4L2_DV_BT_STD_GTF) ? " GTF" : "");
309 }
310 EXPORT_SYMBOL_GPL(v4l2_print_dv_timings);
311
312 /*
313 * CVT defines
314 * Based on Coordinated Video Timings Standard
315 * version 1.1 September 10, 2003
316 */
317
318 #define CVT_PXL_CLK_GRAN 250000 /* pixel clock granularity */
319
320 /* Normal blanking */
321 #define CVT_MIN_V_BPORCH 7 /* lines */
322 #define CVT_MIN_V_PORCH_RND 3 /* lines */
323 #define CVT_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */
324 #define CVT_HSYNC_PERCENT 8 /* nominal hsync as percentage of line */
325
326 /* Normal blanking for CVT uses GTF to calculate horizontal blanking */
327 #define CVT_CELL_GRAN 8 /* character cell granularity */
328 #define CVT_M 600 /* blanking formula gradient */
329 #define CVT_C 40 /* blanking formula offset */
330 #define CVT_K 128 /* blanking formula scaling factor */
331 #define CVT_J 20 /* blanking formula scaling factor */
332 #define CVT_C_PRIME (((CVT_C - CVT_J) * CVT_K / 256) + CVT_J)
333 #define CVT_M_PRIME (CVT_K * CVT_M / 256)
334
335 /* Reduced Blanking */
336 #define CVT_RB_MIN_V_BPORCH 7 /* lines */
337 #define CVT_RB_V_FPORCH 3 /* lines */
338 #define CVT_RB_MIN_V_BLANK 460 /* us */
339 #define CVT_RB_H_SYNC 32 /* pixels */
340 #define CVT_RB_H_BPORCH 80 /* pixels */
341 #define CVT_RB_H_BLANK 160 /* pixels */
342
343 /** v4l2_detect_cvt - detect if the given timings follow the CVT standard
344 * @frame_height - the total height of the frame (including blanking) in lines.
345 * @hfreq - the horizontal frequency in Hz.
346 * @vsync - the height of the vertical sync in lines.
347 * @polarities - the horizontal and vertical polarities (same as struct
348 * v4l2_bt_timings polarities).
349 * @interlaced - if this flag is true, it indicates interlaced format
350 * @fmt - the resulting timings.
351 *
352 * This function will attempt to detect if the given values correspond to a
353 * valid CVT format. If so, then it will return true, and fmt will be filled
354 * in with the found CVT timings.
355 *
356 * TODO: VESA defined a new version 2 of their reduced blanking
357 * formula. Support for that is currently missing in this CVT
358 * detection function.
359 */
360 bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync,
361 u32 polarities, bool interlaced, struct v4l2_dv_timings *fmt)
362 {
363 int v_fp, v_bp, h_fp, h_bp, hsync;
364 int frame_width, image_height, image_width;
365 bool reduced_blanking;
366 unsigned pix_clk;
367
368 if (vsync < 4 || vsync > 7)
369 return false;
370
371 if (polarities == V4L2_DV_VSYNC_POS_POL)
372 reduced_blanking = false;
373 else if (polarities == V4L2_DV_HSYNC_POS_POL)
374 reduced_blanking = true;
375 else
376 return false;
377
378 if (hfreq == 0)
379 return false;
380
381 /* Vertical */
382 if (reduced_blanking) {
383 v_fp = CVT_RB_V_FPORCH;
384 v_bp = (CVT_RB_MIN_V_BLANK * hfreq) / 1000000 + 1;
385 v_bp -= vsync + v_fp;
386
387 if (v_bp < CVT_RB_MIN_V_BPORCH)
388 v_bp = CVT_RB_MIN_V_BPORCH;
389 } else {
390 v_fp = CVT_MIN_V_PORCH_RND;
391 v_bp = (CVT_MIN_VSYNC_BP * hfreq) / 1000000 + 1 - vsync;
392
393 if (v_bp < CVT_MIN_V_BPORCH)
394 v_bp = CVT_MIN_V_BPORCH;
395 }
396
397 if (interlaced)
398 image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1;
399 else
400 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
401
402 if (image_height < 0)
403 return false;
404
405 /* Aspect ratio based on vsync */
406 switch (vsync) {
407 case 4:
408 image_width = (image_height * 4) / 3;
409 break;
410 case 5:
411 image_width = (image_height * 16) / 9;
412 break;
413 case 6:
414 image_width = (image_height * 16) / 10;
415 break;
416 case 7:
417 /* special case */
418 if (image_height == 1024)
419 image_width = (image_height * 5) / 4;
420 else if (image_height == 768)
421 image_width = (image_height * 15) / 9;
422 else
423 return false;
424 break;
425 default:
426 return false;
427 }
428
429 image_width = image_width & ~7;
430
431 /* Horizontal */
432 if (reduced_blanking) {
433 pix_clk = (image_width + CVT_RB_H_BLANK) * hfreq;
434 pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
435
436 h_bp = CVT_RB_H_BPORCH;
437 hsync = CVT_RB_H_SYNC;
438 h_fp = CVT_RB_H_BLANK - h_bp - hsync;
439
440 frame_width = image_width + CVT_RB_H_BLANK;
441 } else {
442 unsigned ideal_duty_cycle_per_myriad =
443 100 * CVT_C_PRIME - (CVT_M_PRIME * 100000) / hfreq;
444 int h_blank;
445
446 if (ideal_duty_cycle_per_myriad < 2000)
447 ideal_duty_cycle_per_myriad = 2000;
448
449 h_blank = image_width * ideal_duty_cycle_per_myriad /
450 (10000 - ideal_duty_cycle_per_myriad);
451 h_blank = (h_blank / (2 * CVT_CELL_GRAN)) * 2 * CVT_CELL_GRAN;
452
453 pix_clk = (image_width + h_blank) * hfreq;
454 pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
455
456 h_bp = h_blank / 2;
457 frame_width = image_width + h_blank;
458
459 hsync = frame_width * CVT_HSYNC_PERCENT / 100;
460 hsync = (hsync / CVT_CELL_GRAN) * CVT_CELL_GRAN;
461 h_fp = h_blank - hsync - h_bp;
462 }
463
464 fmt->type = V4L2_DV_BT_656_1120;
465 fmt->bt.polarities = polarities;
466 fmt->bt.width = image_width;
467 fmt->bt.height = image_height;
468 fmt->bt.hfrontporch = h_fp;
469 fmt->bt.vfrontporch = v_fp;
470 fmt->bt.hsync = hsync;
471 fmt->bt.vsync = vsync;
472 fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
473
474 if (!interlaced) {
475 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
476 fmt->bt.interlaced = V4L2_DV_PROGRESSIVE;
477 } else {
478 fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp -
479 2 * vsync) / 2;
480 fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp -
481 2 * vsync - fmt->bt.vbackporch;
482 fmt->bt.il_vfrontporch = v_fp;
483 fmt->bt.il_vsync = vsync;
484 fmt->bt.flags |= V4L2_DV_FL_HALF_LINE;
485 fmt->bt.interlaced = V4L2_DV_INTERLACED;
486 }
487
488 fmt->bt.pixelclock = pix_clk;
489 fmt->bt.standards = V4L2_DV_BT_STD_CVT;
490
491 if (reduced_blanking)
492 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
493
494 return true;
495 }
496 EXPORT_SYMBOL_GPL(v4l2_detect_cvt);
497
498 /*
499 * GTF defines
500 * Based on Generalized Timing Formula Standard
501 * Version 1.1 September 2, 1999
502 */
503
504 #define GTF_PXL_CLK_GRAN 250000 /* pixel clock granularity */
505
506 #define GTF_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */
507 #define GTF_V_FP 1 /* vertical front porch (lines) */
508 #define GTF_CELL_GRAN 8 /* character cell granularity */
509
510 /* Default */
511 #define GTF_D_M 600 /* blanking formula gradient */
512 #define GTF_D_C 40 /* blanking formula offset */
513 #define GTF_D_K 128 /* blanking formula scaling factor */
514 #define GTF_D_J 20 /* blanking formula scaling factor */
515 #define GTF_D_C_PRIME ((((GTF_D_C - GTF_D_J) * GTF_D_K) / 256) + GTF_D_J)
516 #define GTF_D_M_PRIME ((GTF_D_K * GTF_D_M) / 256)
517
518 /* Secondary */
519 #define GTF_S_M 3600 /* blanking formula gradient */
520 #define GTF_S_C 40 /* blanking formula offset */
521 #define GTF_S_K 128 /* blanking formula scaling factor */
522 #define GTF_S_J 35 /* blanking formula scaling factor */
523 #define GTF_S_C_PRIME ((((GTF_S_C - GTF_S_J) * GTF_S_K) / 256) + GTF_S_J)
524 #define GTF_S_M_PRIME ((GTF_S_K * GTF_S_M) / 256)
525
526 /** v4l2_detect_gtf - detect if the given timings follow the GTF standard
527 * @frame_height - the total height of the frame (including blanking) in lines.
528 * @hfreq - the horizontal frequency in Hz.
529 * @vsync - the height of the vertical sync in lines.
530 * @polarities - the horizontal and vertical polarities (same as struct
531 * v4l2_bt_timings polarities).
532 * @interlaced - if this flag is true, it indicates interlaced format
533 * @aspect - preferred aspect ratio. GTF has no method of determining the
534 * aspect ratio in order to derive the image width from the
535 * image height, so it has to be passed explicitly. Usually
536 * the native screen aspect ratio is used for this. If it
537 * is not filled in correctly, then 16:9 will be assumed.
538 * @fmt - the resulting timings.
539 *
540 * This function will attempt to detect if the given values correspond to a
541 * valid GTF format. If so, then it will return true, and fmt will be filled
542 * in with the found GTF timings.
543 */
544 bool v4l2_detect_gtf(unsigned frame_height,
545 unsigned hfreq,
546 unsigned vsync,
547 u32 polarities,
548 bool interlaced,
549 struct v4l2_fract aspect,
550 struct v4l2_dv_timings *fmt)
551 {
552 int pix_clk;
553 int v_fp, v_bp, h_fp, hsync;
554 int frame_width, image_height, image_width;
555 bool default_gtf;
556 int h_blank;
557
558 if (vsync != 3)
559 return false;
560
561 if (polarities == V4L2_DV_VSYNC_POS_POL)
562 default_gtf = true;
563 else if (polarities == V4L2_DV_HSYNC_POS_POL)
564 default_gtf = false;
565 else
566 return false;
567
568 if (hfreq == 0)
569 return false;
570
571 /* Vertical */
572 v_fp = GTF_V_FP;
573 v_bp = (GTF_MIN_VSYNC_BP * hfreq + 500000) / 1000000 - vsync;
574 if (interlaced)
575 image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1;
576 else
577 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
578
579 if (image_height < 0)
580 return false;
581
582 if (aspect.numerator == 0 || aspect.denominator == 0) {
583 aspect.numerator = 16;
584 aspect.denominator = 9;
585 }
586 image_width = ((image_height * aspect.numerator) / aspect.denominator);
587 image_width = (image_width + GTF_CELL_GRAN/2) & ~(GTF_CELL_GRAN - 1);
588
589 /* Horizontal */
590 if (default_gtf) {
591 u64 num;
592 u32 den;
593
594 num = ((image_width * GTF_D_C_PRIME * (u64)hfreq) -
595 ((u64)image_width * GTF_D_M_PRIME * 1000));
596 den = (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) *
597 (2 * GTF_CELL_GRAN);
598 h_blank = div_u64((num + (den >> 1)), den);
599 h_blank *= (2 * GTF_CELL_GRAN);
600 } else {
601 u64 num;
602 u32 den;
603
604 num = ((image_width * GTF_S_C_PRIME * (u64)hfreq) -
605 ((u64)image_width * GTF_S_M_PRIME * 1000));
606 den = (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) *
607 (2 * GTF_CELL_GRAN);
608 h_blank = div_u64((num + (den >> 1)), den);
609 h_blank *= (2 * GTF_CELL_GRAN);
610 }
611
612 frame_width = image_width + h_blank;
613
614 pix_clk = (image_width + h_blank) * hfreq;
615 pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN;
616
617 hsync = (frame_width * 8 + 50) / 100;
618 hsync = ((hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN) * GTF_CELL_GRAN;
619
620 h_fp = h_blank / 2 - hsync;
621
622 fmt->type = V4L2_DV_BT_656_1120;
623 fmt->bt.polarities = polarities;
624 fmt->bt.width = image_width;
625 fmt->bt.height = image_height;
626 fmt->bt.hfrontporch = h_fp;
627 fmt->bt.vfrontporch = v_fp;
628 fmt->bt.hsync = hsync;
629 fmt->bt.vsync = vsync;
630 fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
631
632 if (!interlaced) {
633 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
634 fmt->bt.interlaced = V4L2_DV_PROGRESSIVE;
635 } else {
636 fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp -
637 2 * vsync) / 2;
638 fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp -
639 2 * vsync - fmt->bt.vbackporch;
640 fmt->bt.il_vfrontporch = v_fp;
641 fmt->bt.il_vsync = vsync;
642 fmt->bt.flags |= V4L2_DV_FL_HALF_LINE;
643 fmt->bt.interlaced = V4L2_DV_INTERLACED;
644 }
645
646 fmt->bt.pixelclock = pix_clk;
647 fmt->bt.standards = V4L2_DV_BT_STD_GTF;
648
649 if (!default_gtf)
650 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
651
652 return true;
653 }
654 EXPORT_SYMBOL_GPL(v4l2_detect_gtf);
655
656 /** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
657 * 0x15 and 0x16 from the EDID.
658 * @hor_landscape - byte 0x15 from the EDID.
659 * @vert_portrait - byte 0x16 from the EDID.
660 *
661 * Determines the aspect ratio from the EDID.
662 * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
663 * "Horizontal and Vertical Screen Size or Aspect Ratio"
664 */
665 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait)
666 {
667 struct v4l2_fract aspect = { 16, 9 };
668 u32 tmp;
669 u8 ratio;
670
671 /* Nothing filled in, fallback to 16:9 */
672 if (!hor_landscape && !vert_portrait)
673 return aspect;
674 /* Both filled in, so they are interpreted as the screen size in cm */
675 if (hor_landscape && vert_portrait) {
676 aspect.numerator = hor_landscape;
677 aspect.denominator = vert_portrait;
678 return aspect;
679 }
680 /* Only one is filled in, so interpret them as a ratio:
681 (val + 99) / 100 */
682 ratio = hor_landscape | vert_portrait;
683 /* Change some rounded values into the exact aspect ratio */
684 if (ratio == 79) {
685 aspect.numerator = 16;
686 aspect.denominator = 9;
687 } else if (ratio == 34) {
688 aspect.numerator = 4;
689 aspect.denominator = 3;
690 } else if (ratio == 68) {
691 aspect.numerator = 15;
692 aspect.denominator = 9;
693 } else {
694 aspect.numerator = hor_landscape + 99;
695 aspect.denominator = 100;
696 }
697 if (hor_landscape)
698 return aspect;
699 /* The aspect ratio is for portrait, so swap numerator and denominator */
700 tmp = aspect.denominator;
701 aspect.denominator = aspect.numerator;
702 aspect.numerator = tmp;
703 return aspect;
704 }
705 EXPORT_SYMBOL_GPL(v4l2_calc_aspect_ratio);
Linux kernel - Deliverables
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