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x86/xen: resume timer irqs early
[linux/fpc-iii.git] / drivers / media / v4l2-core / v4l2-dv-timings.c
blob9f2ac588661b732eddb1deab259fcb9cad0257cc
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
29 MODULE_AUTHOR("Hans Verkuil");
30 MODULE_DESCRIPTION("V4L2 DV Timings Helper Functions");
31 MODULE_LICENSE("GPL");
32
33 const struct v4l2_dv_timings v4l2_dv_timings_presets[] = {
34 V4L2_DV_BT_CEA_640X480P59_94,
35 V4L2_DV_BT_CEA_720X480I59_94,
36 V4L2_DV_BT_CEA_720X480P59_94,
37 V4L2_DV_BT_CEA_720X576I50,
38 V4L2_DV_BT_CEA_720X576P50,
39 V4L2_DV_BT_CEA_1280X720P24,
40 V4L2_DV_BT_CEA_1280X720P25,
41 V4L2_DV_BT_CEA_1280X720P30,
42 V4L2_DV_BT_CEA_1280X720P50,
43 V4L2_DV_BT_CEA_1280X720P60,
44 V4L2_DV_BT_CEA_1920X1080P24,
45 V4L2_DV_BT_CEA_1920X1080P25,
46 V4L2_DV_BT_CEA_1920X1080P30,
47 V4L2_DV_BT_CEA_1920X1080I50,
48 V4L2_DV_BT_CEA_1920X1080P50,
49 V4L2_DV_BT_CEA_1920X1080I60,
50 V4L2_DV_BT_CEA_1920X1080P60,
51 V4L2_DV_BT_DMT_640X350P85,
52 V4L2_DV_BT_DMT_640X400P85,
53 V4L2_DV_BT_DMT_720X400P85,
54 V4L2_DV_BT_DMT_640X480P72,
55 V4L2_DV_BT_DMT_640X480P75,
56 V4L2_DV_BT_DMT_640X480P85,
57 V4L2_DV_BT_DMT_800X600P56,
58 V4L2_DV_BT_DMT_800X600P60,
59 V4L2_DV_BT_DMT_800X600P72,
60 V4L2_DV_BT_DMT_800X600P75,
61 V4L2_DV_BT_DMT_800X600P85,
62 V4L2_DV_BT_DMT_800X600P120_RB,
63 V4L2_DV_BT_DMT_848X480P60,
64 V4L2_DV_BT_DMT_1024X768I43,
65 V4L2_DV_BT_DMT_1024X768P60,
66 V4L2_DV_BT_DMT_1024X768P70,
67 V4L2_DV_BT_DMT_1024X768P75,
68 V4L2_DV_BT_DMT_1024X768P85,
69 V4L2_DV_BT_DMT_1024X768P120_RB,
70 V4L2_DV_BT_DMT_1152X864P75,
71 V4L2_DV_BT_DMT_1280X768P60_RB,
72 V4L2_DV_BT_DMT_1280X768P60,
73 V4L2_DV_BT_DMT_1280X768P75,
74 V4L2_DV_BT_DMT_1280X768P85,
75 V4L2_DV_BT_DMT_1280X768P120_RB,
76 V4L2_DV_BT_DMT_1280X800P60_RB,
77 V4L2_DV_BT_DMT_1280X800P60,
78 V4L2_DV_BT_DMT_1280X800P75,
79 V4L2_DV_BT_DMT_1280X800P85,
80 V4L2_DV_BT_DMT_1280X800P120_RB,
81 V4L2_DV_BT_DMT_1280X960P60,
82 V4L2_DV_BT_DMT_1280X960P85,
83 V4L2_DV_BT_DMT_1280X960P120_RB,
84 V4L2_DV_BT_DMT_1280X1024P60,
85 V4L2_DV_BT_DMT_1280X1024P75,
86 V4L2_DV_BT_DMT_1280X1024P85,
87 V4L2_DV_BT_DMT_1280X1024P120_RB,
88 V4L2_DV_BT_DMT_1360X768P60,
89 V4L2_DV_BT_DMT_1360X768P120_RB,
90 V4L2_DV_BT_DMT_1366X768P60,
91 V4L2_DV_BT_DMT_1366X768P60_RB,
92 V4L2_DV_BT_DMT_1400X1050P60_RB,
93 V4L2_DV_BT_DMT_1400X1050P60,
94 V4L2_DV_BT_DMT_1400X1050P75,
95 V4L2_DV_BT_DMT_1400X1050P85,
96 V4L2_DV_BT_DMT_1400X1050P120_RB,
97 V4L2_DV_BT_DMT_1440X900P60_RB,
98 V4L2_DV_BT_DMT_1440X900P60,
99 V4L2_DV_BT_DMT_1440X900P75,
100 V4L2_DV_BT_DMT_1440X900P85,
101 V4L2_DV_BT_DMT_1440X900P120_RB,
102 V4L2_DV_BT_DMT_1600X900P60_RB,
103 V4L2_DV_BT_DMT_1600X1200P60,
104 V4L2_DV_BT_DMT_1600X1200P65,
105 V4L2_DV_BT_DMT_1600X1200P70,
106 V4L2_DV_BT_DMT_1600X1200P75,
107 V4L2_DV_BT_DMT_1600X1200P85,
108 V4L2_DV_BT_DMT_1600X1200P120_RB,
109 V4L2_DV_BT_DMT_1680X1050P60_RB,
110 V4L2_DV_BT_DMT_1680X1050P60,
111 V4L2_DV_BT_DMT_1680X1050P75,
112 V4L2_DV_BT_DMT_1680X1050P85,
113 V4L2_DV_BT_DMT_1680X1050P120_RB,
114 V4L2_DV_BT_DMT_1792X1344P60,
115 V4L2_DV_BT_DMT_1792X1344P75,
116 V4L2_DV_BT_DMT_1792X1344P120_RB,
117 V4L2_DV_BT_DMT_1856X1392P60,
118 V4L2_DV_BT_DMT_1856X1392P75,
119 V4L2_DV_BT_DMT_1856X1392P120_RB,
120 V4L2_DV_BT_DMT_1920X1200P60_RB,
121 V4L2_DV_BT_DMT_1920X1200P60,
122 V4L2_DV_BT_DMT_1920X1200P75,
123 V4L2_DV_BT_DMT_1920X1200P85,
124 V4L2_DV_BT_DMT_1920X1200P120_RB,
125 V4L2_DV_BT_DMT_1920X1440P60,
126 V4L2_DV_BT_DMT_1920X1440P75,
127 V4L2_DV_BT_DMT_1920X1440P120_RB,
128 V4L2_DV_BT_DMT_2048X1152P60_RB,
129 V4L2_DV_BT_DMT_2560X1600P60_RB,
130 V4L2_DV_BT_DMT_2560X1600P60,
131 V4L2_DV_BT_DMT_2560X1600P75,
132 V4L2_DV_BT_DMT_2560X1600P85,
133 V4L2_DV_BT_DMT_2560X1600P120_RB,
134 { }
135 };
136 EXPORT_SYMBOL_GPL(v4l2_dv_timings_presets);
137
138 bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
139 const struct v4l2_dv_timings_cap *dvcap,
140 v4l2_check_dv_timings_fnc fnc,
141 void *fnc_handle)
142 {
143 const struct v4l2_bt_timings *bt = &t->bt;
144 const struct v4l2_bt_timings_cap *cap = &dvcap->bt;
145 u32 caps = cap->capabilities;
146
147 if (t->type != V4L2_DV_BT_656_1120)
148 return false;
149 if (t->type != dvcap->type ||
150 bt->height < cap->min_height ||
151 bt->height > cap->max_height ||
152 bt->width < cap->min_width ||
153 bt->width > cap->max_width ||
154 bt->pixelclock < cap->min_pixelclock ||
155 bt->pixelclock > cap->max_pixelclock ||
156 (cap->standards && !(bt->standards & cap->standards)) ||
157 (bt->interlaced && !(caps & V4L2_DV_BT_CAP_INTERLACED)) ||
158 (!bt->interlaced && !(caps & V4L2_DV_BT_CAP_PROGRESSIVE)))
159 return false;
160 return fnc == NULL || fnc(t, fnc_handle);
161 }
162 EXPORT_SYMBOL_GPL(v4l2_valid_dv_timings);
163
164 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t,
165 const struct v4l2_dv_timings_cap *cap,
166 v4l2_check_dv_timings_fnc fnc,
167 void *fnc_handle)
168 {
169 u32 i, idx;
170
171 memset(t->reserved, 0, sizeof(t->reserved));
172 for (i = idx = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
173 if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
174 fnc, fnc_handle) &&
175 idx++ == t->index) {
176 t->timings = v4l2_dv_timings_presets[i];
177 return 0;
178 }
179 }
180 return -EINVAL;
181 }
182 EXPORT_SYMBOL_GPL(v4l2_enum_dv_timings_cap);
183
184 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t,
185 const struct v4l2_dv_timings_cap *cap,
186 unsigned pclock_delta,
187 v4l2_check_dv_timings_fnc fnc,
188 void *fnc_handle)
189 {
190 int i;
191
192 if (!v4l2_valid_dv_timings(t, cap, fnc, fnc_handle))
193 return false;
194
195 for (i = 0; i < v4l2_dv_timings_presets[i].bt.width; i++) {
196 if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
197 fnc, fnc_handle) &&
198 v4l2_match_dv_timings(t, v4l2_dv_timings_presets + i,
199 pclock_delta)) {
200 *t = v4l2_dv_timings_presets[i];
201 return true;
202 }
203 }
204 return false;
205 }
206 EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cap);
207
208 /**
209 * v4l2_match_dv_timings - check if two timings match
210 * @t1 - compare this v4l2_dv_timings struct...
211 * @t2 - with this struct.
212 * @pclock_delta - the allowed pixelclock deviation.
213 *
214 * Compare t1 with t2 with a given margin of error for the pixelclock.
215 */
216 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *t1,
217 const struct v4l2_dv_timings *t2,
218 unsigned pclock_delta)
219 {
220 if (t1->type != t2->type || t1->type != V4L2_DV_BT_656_1120)
221 return false;
222 if (t1->bt.width == t2->bt.width &&
223 t1->bt.height == t2->bt.height &&
224 t1->bt.interlaced == t2->bt.interlaced &&
225 t1->bt.polarities == t2->bt.polarities &&
226 t1->bt.pixelclock >= t2->bt.pixelclock - pclock_delta &&
227 t1->bt.pixelclock <= t2->bt.pixelclock + pclock_delta &&
228 t1->bt.hfrontporch == t2->bt.hfrontporch &&
229 t1->bt.vfrontporch == t2->bt.vfrontporch &&
230 t1->bt.vsync == t2->bt.vsync &&
231 t1->bt.vbackporch == t2->bt.vbackporch &&
232 (!t1->bt.interlaced ||
233 (t1->bt.il_vfrontporch == t2->bt.il_vfrontporch &&
234 t1->bt.il_vsync == t2->bt.il_vsync &&
235 t1->bt.il_vbackporch == t2->bt.il_vbackporch)))
236 return true;
237 return false;
238 }
239 EXPORT_SYMBOL_GPL(v4l2_match_dv_timings);
240
241 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix,
242 const struct v4l2_dv_timings *t, bool detailed)
243 {
244 const struct v4l2_bt_timings *bt = &t->bt;
245 u32 htot, vtot;
246
247 if (t->type != V4L2_DV_BT_656_1120)
248 return;
249
250 htot = V4L2_DV_BT_FRAME_WIDTH(bt);
251 vtot = V4L2_DV_BT_FRAME_HEIGHT(bt);
252
253 if (prefix == NULL)
254 prefix = "";
255
256 pr_info("%s: %s%ux%u%s%u (%ux%u)\n", dev_prefix, prefix,
257 bt->width, bt->height, bt->interlaced ? "i" : "p",
258 (htot * vtot) > 0 ? ((u32)bt->pixelclock / (htot * vtot)) : 0,
259 htot, vtot);
260
261 if (!detailed)
262 return;
263
264 pr_info("%s: horizontal: fp = %u, %ssync = %u, bp = %u\n",
265 dev_prefix, bt->hfrontporch,
266 (bt->polarities & V4L2_DV_HSYNC_POS_POL) ? "+" : "-",
267 bt->hsync, bt->hbackporch);
268 pr_info("%s: vertical: fp = %u, %ssync = %u, bp = %u\n",
269 dev_prefix, bt->vfrontporch,
270 (bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
271 bt->vsync, bt->vbackporch);
272 pr_info("%s: pixelclock: %llu\n", dev_prefix, bt->pixelclock);
273 pr_info("%s: flags (0x%x):%s%s%s%s\n", dev_prefix, bt->flags,
274 (bt->flags & V4L2_DV_FL_REDUCED_BLANKING) ?
275 " REDUCED_BLANKING" : "",
276 (bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS) ?
277 " CAN_REDUCE_FPS" : "",
278 (bt->flags & V4L2_DV_FL_REDUCED_FPS) ?
279 " REDUCED_FPS" : "",
280 (bt->flags & V4L2_DV_FL_HALF_LINE) ?
281 " HALF_LINE" : "");
282 pr_info("%s: standards (0x%x):%s%s%s%s\n", dev_prefix, bt->standards,
283 (bt->standards & V4L2_DV_BT_STD_CEA861) ? " CEA" : "",
284 (bt->standards & V4L2_DV_BT_STD_DMT) ? " DMT" : "",
285 (bt->standards & V4L2_DV_BT_STD_CVT) ? " CVT" : "",
286 (bt->standards & V4L2_DV_BT_STD_GTF) ? " GTF" : "");
287 }
288 EXPORT_SYMBOL_GPL(v4l2_print_dv_timings);
289
290 /*
291 * CVT defines
292 * Based on Coordinated Video Timings Standard
293 * version 1.1 September 10, 2003
294 */
295
296 #define CVT_PXL_CLK_GRAN 250000 /* pixel clock granularity */
297
298 /* Normal blanking */
299 #define CVT_MIN_V_BPORCH 7 /* lines */
300 #define CVT_MIN_V_PORCH_RND 3 /* lines */
301 #define CVT_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */
302
303 /* Normal blanking for CVT uses GTF to calculate horizontal blanking */
304 #define CVT_CELL_GRAN 8 /* character cell granularity */
305 #define CVT_M 600 /* blanking formula gradient */
306 #define CVT_C 40 /* blanking formula offset */
307 #define CVT_K 128 /* blanking formula scaling factor */
308 #define CVT_J 20 /* blanking formula scaling factor */
309 #define CVT_C_PRIME (((CVT_C - CVT_J) * CVT_K / 256) + CVT_J)
310 #define CVT_M_PRIME (CVT_K * CVT_M / 256)
311
312 /* Reduced Blanking */
313 #define CVT_RB_MIN_V_BPORCH 7 /* lines */
314 #define CVT_RB_V_FPORCH 3 /* lines */
315 #define CVT_RB_MIN_V_BLANK 460 /* us */
316 #define CVT_RB_H_SYNC 32 /* pixels */
317 #define CVT_RB_H_BPORCH 80 /* pixels */
318 #define CVT_RB_H_BLANK 160 /* pixels */
319
320 /** v4l2_detect_cvt - detect if the given timings follow the CVT standard
321 * @frame_height - the total height of the frame (including blanking) in lines.
322 * @hfreq - the horizontal frequency in Hz.
323 * @vsync - the height of the vertical sync in lines.
324 * @polarities - the horizontal and vertical polarities (same as struct
325 * v4l2_bt_timings polarities).
326 * @fmt - the resulting timings.
327 *
328 * This function will attempt to detect if the given values correspond to a
329 * valid CVT format. If so, then it will return true, and fmt will be filled
330 * in with the found CVT timings.
331 */
332 bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync,
333 u32 polarities, struct v4l2_dv_timings *fmt)
334 {
335 int v_fp, v_bp, h_fp, h_bp, hsync;
336 int frame_width, image_height, image_width;
337 bool reduced_blanking;
338 unsigned pix_clk;
339
340 if (vsync < 4 || vsync > 7)
341 return false;
342
343 if (polarities == V4L2_DV_VSYNC_POS_POL)
344 reduced_blanking = false;
345 else if (polarities == V4L2_DV_HSYNC_POS_POL)
346 reduced_blanking = true;
347 else
348 return false;
349
350 /* Vertical */
351 if (reduced_blanking) {
352 v_fp = CVT_RB_V_FPORCH;
353 v_bp = (CVT_RB_MIN_V_BLANK * hfreq + 1999999) / 1000000;
354 v_bp -= vsync + v_fp;
355
356 if (v_bp < CVT_RB_MIN_V_BPORCH)
357 v_bp = CVT_RB_MIN_V_BPORCH;
358 } else {
359 v_fp = CVT_MIN_V_PORCH_RND;
360 v_bp = (CVT_MIN_VSYNC_BP * hfreq + 1999999) / 1000000 - vsync;
361
362 if (v_bp < CVT_MIN_V_BPORCH)
363 v_bp = CVT_MIN_V_BPORCH;
364 }
365 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
366
367 /* Aspect ratio based on vsync */
368 switch (vsync) {
369 case 4:
370 image_width = (image_height * 4) / 3;
371 break;
372 case 5:
373 image_width = (image_height * 16) / 9;
374 break;
375 case 6:
376 image_width = (image_height * 16) / 10;
377 break;
378 case 7:
379 /* special case */
380 if (image_height == 1024)
381 image_width = (image_height * 5) / 4;
382 else if (image_height == 768)
383 image_width = (image_height * 15) / 9;
384 else
385 return false;
386 break;
387 default:
388 return false;
389 }
390
391 image_width = image_width & ~7;
392
393 /* Horizontal */
394 if (reduced_blanking) {
395 pix_clk = (image_width + CVT_RB_H_BLANK) * hfreq;
396 pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
397
398 h_bp = CVT_RB_H_BPORCH;
399 hsync = CVT_RB_H_SYNC;
400 h_fp = CVT_RB_H_BLANK - h_bp - hsync;
401
402 frame_width = image_width + CVT_RB_H_BLANK;
403 } else {
404 unsigned ideal_duty_cycle_per_myriad =
405 100 * CVT_C_PRIME - (CVT_M_PRIME * 100000) / hfreq;
406 int h_blank;
407
408 if (ideal_duty_cycle_per_myriad < 2000)
409 ideal_duty_cycle_per_myriad = 2000;
410
411 h_blank = image_width * ideal_duty_cycle_per_myriad /
412 (10000 - ideal_duty_cycle_per_myriad);
413 h_blank = (h_blank / (2 * CVT_CELL_GRAN)) * 2 * CVT_CELL_GRAN;
414
415 pix_clk = (image_width + h_blank) * hfreq;
416 pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
417
418 h_bp = h_blank / 2;
419 frame_width = image_width + h_blank;
420
421 hsync = (frame_width * 8 + 50) / 100;
422 hsync = hsync - hsync % CVT_CELL_GRAN;
423 h_fp = h_blank - hsync - h_bp;
424 }
425
426 fmt->type = V4L2_DV_BT_656_1120;
427 fmt->bt.polarities = polarities;
428 fmt->bt.width = image_width;
429 fmt->bt.height = image_height;
430 fmt->bt.hfrontporch = h_fp;
431 fmt->bt.vfrontporch = v_fp;
432 fmt->bt.hsync = hsync;
433 fmt->bt.vsync = vsync;
434 fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
435 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
436 fmt->bt.pixelclock = pix_clk;
437 fmt->bt.standards = V4L2_DV_BT_STD_CVT;
438 if (reduced_blanking)
439 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
440 return true;
441 }
442 EXPORT_SYMBOL_GPL(v4l2_detect_cvt);
443
444 /*
445 * GTF defines
446 * Based on Generalized Timing Formula Standard
447 * Version 1.1 September 2, 1999
448 */
449
450 #define GTF_PXL_CLK_GRAN 250000 /* pixel clock granularity */
451
452 #define GTF_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */
453 #define GTF_V_FP 1 /* vertical front porch (lines) */
454 #define GTF_CELL_GRAN 8 /* character cell granularity */
455
456 /* Default */
457 #define GTF_D_M 600 /* blanking formula gradient */
458 #define GTF_D_C 40 /* blanking formula offset */
459 #define GTF_D_K 128 /* blanking formula scaling factor */
460 #define GTF_D_J 20 /* blanking formula scaling factor */
461 #define GTF_D_C_PRIME ((((GTF_D_C - GTF_D_J) * GTF_D_K) / 256) + GTF_D_J)
462 #define GTF_D_M_PRIME ((GTF_D_K * GTF_D_M) / 256)
463
464 /* Secondary */
465 #define GTF_S_M 3600 /* blanking formula gradient */
466 #define GTF_S_C 40 /* blanking formula offset */
467 #define GTF_S_K 128 /* blanking formula scaling factor */
468 #define GTF_S_J 35 /* blanking formula scaling factor */
469 #define GTF_S_C_PRIME ((((GTF_S_C - GTF_S_J) * GTF_S_K) / 256) + GTF_S_J)
470 #define GTF_S_M_PRIME ((GTF_S_K * GTF_S_M) / 256)
471
472 /** v4l2_detect_gtf - detect if the given timings follow the GTF standard
473 * @frame_height - the total height of the frame (including blanking) in lines.
474 * @hfreq - the horizontal frequency in Hz.
475 * @vsync - the height of the vertical sync in lines.
476 * @polarities - the horizontal and vertical polarities (same as struct
477 * v4l2_bt_timings polarities).
478 * @aspect - preferred aspect ratio. GTF has no method of determining the
479 * aspect ratio in order to derive the image width from the
480 * image height, so it has to be passed explicitly. Usually
481 * the native screen aspect ratio is used for this. If it
482 * is not filled in correctly, then 16:9 will be assumed.
483 * @fmt - the resulting timings.
484 *
485 * This function will attempt to detect if the given values correspond to a
486 * valid GTF format. If so, then it will return true, and fmt will be filled
487 * in with the found GTF timings.
488 */
489 bool v4l2_detect_gtf(unsigned frame_height,
490 unsigned hfreq,
491 unsigned vsync,
492 u32 polarities,
493 struct v4l2_fract aspect,
494 struct v4l2_dv_timings *fmt)
495 {
496 int pix_clk;
497 int v_fp, v_bp, h_fp, hsync;
498 int frame_width, image_height, image_width;
499 bool default_gtf;
500 int h_blank;
501
502 if (vsync != 3)
503 return false;
504
505 if (polarities == V4L2_DV_VSYNC_POS_POL)
506 default_gtf = true;
507 else if (polarities == V4L2_DV_HSYNC_POS_POL)
508 default_gtf = false;
509 else
510 return false;
511
512 /* Vertical */
513 v_fp = GTF_V_FP;
514 v_bp = (GTF_MIN_VSYNC_BP * hfreq + 999999) / 1000000 - vsync;
515 image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
516
517 if (aspect.numerator == 0 || aspect.denominator == 0) {
518 aspect.numerator = 16;
519 aspect.denominator = 9;
520 }
521 image_width = ((image_height * aspect.numerator) / aspect.denominator);
522
523 /* Horizontal */
524 if (default_gtf)
525 h_blank = ((image_width * GTF_D_C_PRIME * hfreq) -
526 (image_width * GTF_D_M_PRIME * 1000) +
527 (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) / 2) /
528 (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000);
529 else
530 h_blank = ((image_width * GTF_S_C_PRIME * hfreq) -
531 (image_width * GTF_S_M_PRIME * 1000) +
532 (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) / 2) /
533 (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000);
534
535 h_blank = h_blank - h_blank % (2 * GTF_CELL_GRAN);
536 frame_width = image_width + h_blank;
537
538 pix_clk = (image_width + h_blank) * hfreq;
539 pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN;
540
541 hsync = (frame_width * 8 + 50) / 100;
542 hsync = hsync - hsync % GTF_CELL_GRAN;
543
544 h_fp = h_blank / 2 - hsync;
545
546 fmt->type = V4L2_DV_BT_656_1120;
547 fmt->bt.polarities = polarities;
548 fmt->bt.width = image_width;
549 fmt->bt.height = image_height;
550 fmt->bt.hfrontporch = h_fp;
551 fmt->bt.vfrontporch = v_fp;
552 fmt->bt.hsync = hsync;
553 fmt->bt.vsync = vsync;
554 fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
555 fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
556 fmt->bt.pixelclock = pix_clk;
557 fmt->bt.standards = V4L2_DV_BT_STD_GTF;
558 if (!default_gtf)
559 fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
560 return true;
561 }
562 EXPORT_SYMBOL_GPL(v4l2_detect_gtf);
563
564 /** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
565 * 0x15 and 0x16 from the EDID.
566 * @hor_landscape - byte 0x15 from the EDID.
567 * @vert_portrait - byte 0x16 from the EDID.
568 *
569 * Determines the aspect ratio from the EDID.
570 * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
571 * "Horizontal and Vertical Screen Size or Aspect Ratio"
572 */
573 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait)
574 {
575 struct v4l2_fract aspect = { 16, 9 };
576 u32 tmp;
577 u8 ratio;
578
579 /* Nothing filled in, fallback to 16:9 */
580 if (!hor_landscape && !vert_portrait)
581 return aspect;
582 /* Both filled in, so they are interpreted as the screen size in cm */
583 if (hor_landscape && vert_portrait) {
584 aspect.numerator = hor_landscape;
585 aspect.denominator = vert_portrait;
586 return aspect;
587 }
588 /* Only one is filled in, so interpret them as a ratio:
589 (val + 99) / 100 */
590 ratio = hor_landscape | vert_portrait;
591 /* Change some rounded values into the exact aspect ratio */
592 if (ratio == 79) {
593 aspect.numerator = 16;
594 aspect.denominator = 9;
595 } else if (ratio == 34) {
596 aspect.numerator = 4;
597 aspect.denominator = 3;
598 } else if (ratio == 68) {
599 aspect.numerator = 15;
600 aspect.denominator = 9;
601 } else {
602 aspect.numerator = hor_landscape + 99;
603 aspect.denominator = 100;
604 }
605 if (hor_landscape)
606 return aspect;
607 /* The aspect ratio is for portrait, so swap numerator and denominator */
608 tmp = aspect.denominator;
609 aspect.denominator = aspect.numerator;
610 aspect.numerator = tmp;
611 return aspect;
612 }
613 EXPORT_SYMBOL_GPL(v4l2_calc_aspect_ratio);
Linux with added FPC-III support