1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * v4l2-dv-timings - dv-timings helper functions
4  *
5  * Copyright 2013 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
6  */
7 
8 #include <linux/module.h>
9 #include <linux/types.h>
10 #include <linux/kernel.h>
11 #include <linux/errno.h>
12 #include <linux/rational.h>
13 #include <linux/videodev2.h>
14 #include <linux/v4l2-dv-timings.h>
15 #include <media/v4l2-dv-timings.h>
16 #include <linux/math64.h>
17 #include <linux/hdmi.h>
18 #include <media/cec.h>
19 
20 MODULE_AUTHOR("Hans Verkuil");
21 MODULE_DESCRIPTION("V4L2 DV Timings Helper Functions");
22 MODULE_LICENSE("GPL");
23 
24 const struct v4l2_dv_timings v4l2_dv_timings_presets[] = {
25 	V4L2_DV_BT_CEA_640X480P59_94,
26 	V4L2_DV_BT_CEA_720X480I59_94,
27 	V4L2_DV_BT_CEA_720X480P59_94,
28 	V4L2_DV_BT_CEA_720X576I50,
29 	V4L2_DV_BT_CEA_720X576P50,
30 	V4L2_DV_BT_CEA_1280X720P24,
31 	V4L2_DV_BT_CEA_1280X720P25,
32 	V4L2_DV_BT_CEA_1280X720P30,
33 	V4L2_DV_BT_CEA_1280X720P50,
34 	V4L2_DV_BT_CEA_1280X720P60,
35 	V4L2_DV_BT_CEA_1920X1080P24,
36 	V4L2_DV_BT_CEA_1920X1080P25,
37 	V4L2_DV_BT_CEA_1920X1080P30,
38 	V4L2_DV_BT_CEA_1920X1080I50,
39 	V4L2_DV_BT_CEA_1920X1080P50,
40 	V4L2_DV_BT_CEA_1920X1080I60,
41 	V4L2_DV_BT_CEA_1920X1080P60,
42 	V4L2_DV_BT_DMT_640X350P85,
43 	V4L2_DV_BT_DMT_640X400P85,
44 	V4L2_DV_BT_DMT_720X400P85,
45 	V4L2_DV_BT_DMT_640X480P72,
46 	V4L2_DV_BT_DMT_640X480P75,
47 	V4L2_DV_BT_DMT_640X480P85,
48 	V4L2_DV_BT_DMT_800X600P56,
49 	V4L2_DV_BT_DMT_800X600P60,
50 	V4L2_DV_BT_DMT_800X600P72,
51 	V4L2_DV_BT_DMT_800X600P75,
52 	V4L2_DV_BT_DMT_800X600P85,
53 	V4L2_DV_BT_DMT_800X600P120_RB,
54 	V4L2_DV_BT_DMT_848X480P60,
55 	V4L2_DV_BT_DMT_1024X768I43,
56 	V4L2_DV_BT_DMT_1024X768P60,
57 	V4L2_DV_BT_DMT_1024X768P70,
58 	V4L2_DV_BT_DMT_1024X768P75,
59 	V4L2_DV_BT_DMT_1024X768P85,
60 	V4L2_DV_BT_DMT_1024X768P120_RB,
61 	V4L2_DV_BT_DMT_1152X864P75,
62 	V4L2_DV_BT_DMT_1280X768P60_RB,
63 	V4L2_DV_BT_DMT_1280X768P60,
64 	V4L2_DV_BT_DMT_1280X768P75,
65 	V4L2_DV_BT_DMT_1280X768P85,
66 	V4L2_DV_BT_DMT_1280X768P120_RB,
67 	V4L2_DV_BT_DMT_1280X800P60_RB,
68 	V4L2_DV_BT_DMT_1280X800P60,
69 	V4L2_DV_BT_DMT_1280X800P75,
70 	V4L2_DV_BT_DMT_1280X800P85,
71 	V4L2_DV_BT_DMT_1280X800P120_RB,
72 	V4L2_DV_BT_DMT_1280X960P60,
73 	V4L2_DV_BT_DMT_1280X960P85,
74 	V4L2_DV_BT_DMT_1280X960P120_RB,
75 	V4L2_DV_BT_DMT_1280X1024P60,
76 	V4L2_DV_BT_DMT_1280X1024P75,
77 	V4L2_DV_BT_DMT_1280X1024P85,
78 	V4L2_DV_BT_DMT_1280X1024P120_RB,
79 	V4L2_DV_BT_DMT_1360X768P60,
80 	V4L2_DV_BT_DMT_1360X768P120_RB,
81 	V4L2_DV_BT_DMT_1366X768P60,
82 	V4L2_DV_BT_DMT_1366X768P60_RB,
83 	V4L2_DV_BT_DMT_1400X1050P60_RB,
84 	V4L2_DV_BT_DMT_1400X1050P60,
85 	V4L2_DV_BT_DMT_1400X1050P75,
86 	V4L2_DV_BT_DMT_1400X1050P85,
87 	V4L2_DV_BT_DMT_1400X1050P120_RB,
88 	V4L2_DV_BT_DMT_1440X900P60_RB,
89 	V4L2_DV_BT_DMT_1440X900P60,
90 	V4L2_DV_BT_DMT_1440X900P75,
91 	V4L2_DV_BT_DMT_1440X900P85,
92 	V4L2_DV_BT_DMT_1440X900P120_RB,
93 	V4L2_DV_BT_DMT_1600X900P60_RB,
94 	V4L2_DV_BT_DMT_1600X1200P60,
95 	V4L2_DV_BT_DMT_1600X1200P65,
96 	V4L2_DV_BT_DMT_1600X1200P70,
97 	V4L2_DV_BT_DMT_1600X1200P75,
98 	V4L2_DV_BT_DMT_1600X1200P85,
99 	V4L2_DV_BT_DMT_1600X1200P120_RB,
100 	V4L2_DV_BT_DMT_1680X1050P60_RB,
101 	V4L2_DV_BT_DMT_1680X1050P60,
102 	V4L2_DV_BT_DMT_1680X1050P75,
103 	V4L2_DV_BT_DMT_1680X1050P85,
104 	V4L2_DV_BT_DMT_1680X1050P120_RB,
105 	V4L2_DV_BT_DMT_1792X1344P60,
106 	V4L2_DV_BT_DMT_1792X1344P75,
107 	V4L2_DV_BT_DMT_1792X1344P120_RB,
108 	V4L2_DV_BT_DMT_1856X1392P60,
109 	V4L2_DV_BT_DMT_1856X1392P75,
110 	V4L2_DV_BT_DMT_1856X1392P120_RB,
111 	V4L2_DV_BT_DMT_1920X1200P60_RB,
112 	V4L2_DV_BT_DMT_1920X1200P60,
113 	V4L2_DV_BT_DMT_1920X1200P75,
114 	V4L2_DV_BT_DMT_1920X1200P85,
115 	V4L2_DV_BT_DMT_1920X1200P120_RB,
116 	V4L2_DV_BT_DMT_1920X1440P60,
117 	V4L2_DV_BT_DMT_1920X1440P75,
118 	V4L2_DV_BT_DMT_1920X1440P120_RB,
119 	V4L2_DV_BT_DMT_2048X1152P60_RB,
120 	V4L2_DV_BT_DMT_2560X1600P60_RB,
121 	V4L2_DV_BT_DMT_2560X1600P60,
122 	V4L2_DV_BT_DMT_2560X1600P75,
123 	V4L2_DV_BT_DMT_2560X1600P85,
124 	V4L2_DV_BT_DMT_2560X1600P120_RB,
125 	V4L2_DV_BT_CEA_3840X2160P24,
126 	V4L2_DV_BT_CEA_3840X2160P25,
127 	V4L2_DV_BT_CEA_3840X2160P30,
128 	V4L2_DV_BT_CEA_3840X2160P50,
129 	V4L2_DV_BT_CEA_3840X2160P60,
130 	V4L2_DV_BT_CEA_4096X2160P24,
131 	V4L2_DV_BT_CEA_4096X2160P25,
132 	V4L2_DV_BT_CEA_4096X2160P30,
133 	V4L2_DV_BT_CEA_4096X2160P50,
134 	V4L2_DV_BT_DMT_4096X2160P59_94_RB,
135 	V4L2_DV_BT_CEA_4096X2160P60,
136 	{ }
137 };
138 EXPORT_SYMBOL_GPL(v4l2_dv_timings_presets);
139 
v4l2_valid_dv_timings(const struct v4l2_dv_timings * t,const struct v4l2_dv_timings_cap * dvcap,v4l2_check_dv_timings_fnc fnc,void * fnc_handle)140 bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
141 			   const struct v4l2_dv_timings_cap *dvcap,
142 			   v4l2_check_dv_timings_fnc fnc,
143 			   void *fnc_handle)
144 {
145 	const struct v4l2_bt_timings *bt = &t->bt;
146 	const struct v4l2_bt_timings_cap *cap = &dvcap->bt;
147 	u32 caps = cap->capabilities;
148 	const u32 max_vert = 10240;
149 	u32 max_hor = 3 * bt->width;
150 
151 	if (t->type != V4L2_DV_BT_656_1120)
152 		return false;
153 	if (t->type != dvcap->type ||
154 	    bt->height < cap->min_height ||
155 	    bt->height > cap->max_height ||
156 	    bt->width < cap->min_width ||
157 	    bt->width > cap->max_width ||
158 	    bt->pixelclock < cap->min_pixelclock ||
159 	    bt->pixelclock > cap->max_pixelclock ||
160 	    (!(caps & V4L2_DV_BT_CAP_CUSTOM) &&
161 	     cap->standards && bt->standards &&
162 	     !(bt->standards & cap->standards)) ||
163 	    (bt->interlaced && !(caps & V4L2_DV_BT_CAP_INTERLACED)) ||
164 	    (!bt->interlaced && !(caps & V4L2_DV_BT_CAP_PROGRESSIVE)))
165 		return false;
166 
167 	/* sanity checks for the blanking timings */
168 	if (!bt->interlaced &&
169 	    (bt->il_vbackporch || bt->il_vsync || bt->il_vfrontporch))
170 		return false;
171 	/*
172 	 * Some video receivers cannot properly separate the frontporch,
173 	 * backporch and sync values, and instead they only have the total
174 	 * blanking. That can be assigned to any of these three fields.
175 	 * So just check that none of these are way out of range.
176 	 */
177 	if (bt->hfrontporch > max_hor ||
178 	    bt->hsync > max_hor || bt->hbackporch > max_hor)
179 		return false;
180 	if (bt->vfrontporch > max_vert ||
181 	    bt->vsync > max_vert || bt->vbackporch > max_vert)
182 		return false;
183 	if (bt->interlaced && (bt->il_vfrontporch > max_vert ||
184 	    bt->il_vsync > max_vert || bt->il_vbackporch > max_vert))
185 		return false;
186 	return fnc == NULL || fnc(t, fnc_handle);
187 }
188 EXPORT_SYMBOL_GPL(v4l2_valid_dv_timings);
189 
v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings * t,const struct v4l2_dv_timings_cap * cap,v4l2_check_dv_timings_fnc fnc,void * fnc_handle)190 int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t,
191 			     const struct v4l2_dv_timings_cap *cap,
192 			     v4l2_check_dv_timings_fnc fnc,
193 			     void *fnc_handle)
194 {
195 	u32 i, idx;
196 
197 	memset(t->reserved, 0, sizeof(t->reserved));
198 	for (i = idx = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
199 		if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
200 					  fnc, fnc_handle) &&
201 		    idx++ == t->index) {
202 			t->timings = v4l2_dv_timings_presets[i];
203 			return 0;
204 		}
205 	}
206 	return -EINVAL;
207 }
208 EXPORT_SYMBOL_GPL(v4l2_enum_dv_timings_cap);
209 
v4l2_find_dv_timings_cap(struct v4l2_dv_timings * t,const struct v4l2_dv_timings_cap * cap,unsigned pclock_delta,v4l2_check_dv_timings_fnc fnc,void * fnc_handle)210 bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t,
211 			      const struct v4l2_dv_timings_cap *cap,
212 			      unsigned pclock_delta,
213 			      v4l2_check_dv_timings_fnc fnc,
214 			      void *fnc_handle)
215 {
216 	int i;
217 
218 	if (!v4l2_valid_dv_timings(t, cap, fnc, fnc_handle))
219 		return false;
220 
221 	for (i = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
222 		if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
223 					  fnc, fnc_handle) &&
224 		    v4l2_match_dv_timings(t, v4l2_dv_timings_presets + i,
225 					  pclock_delta, false)) {
226 			u32 flags = t->bt.flags & V4L2_DV_FL_REDUCED_FPS;
227 
228 			*t = v4l2_dv_timings_presets[i];
229 			if (can_reduce_fps(&t->bt))
230 				t->bt.flags |= flags;
231 
232 			return true;
233 		}
234 	}
235 	return false;
236 }
237 EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cap);
238 
v4l2_find_dv_timings_cea861_vic(struct v4l2_dv_timings * t,u8 vic)239 bool v4l2_find_dv_timings_cea861_vic(struct v4l2_dv_timings *t, u8 vic)
240 {
241 	unsigned int i;
242 
243 	for (i = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
244 		const struct v4l2_bt_timings *bt =
245 			&v4l2_dv_timings_presets[i].bt;
246 
247 		if ((bt->flags & V4L2_DV_FL_HAS_CEA861_VIC) &&
248 		    bt->cea861_vic == vic) {
249 			*t = v4l2_dv_timings_presets[i];
250 			return true;
251 		}
252 	}
253 	return false;
254 }
255 EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cea861_vic);
256 
257 /**
258  * v4l2_match_dv_timings - check if two timings match
259  * @t1: compare this v4l2_dv_timings struct...
260  * @t2: with this struct.
261  * @pclock_delta: the allowed pixelclock deviation.
262  * @match_reduced_fps: if true, then fail if V4L2_DV_FL_REDUCED_FPS does not
263  *	match.
264  *
265  * Compare t1 with t2 with a given margin of error for the pixelclock.
266  */
v4l2_match_dv_timings(const struct v4l2_dv_timings * t1,const struct v4l2_dv_timings * t2,unsigned pclock_delta,bool match_reduced_fps)267 bool v4l2_match_dv_timings(const struct v4l2_dv_timings *t1,
268 			   const struct v4l2_dv_timings *t2,
269 			   unsigned pclock_delta, bool match_reduced_fps)
270 {
271 	if (t1->type != t2->type || t1->type != V4L2_DV_BT_656_1120)
272 		return false;
273 	if (t1->bt.width == t2->bt.width &&
274 	    t1->bt.height == t2->bt.height &&
275 	    t1->bt.interlaced == t2->bt.interlaced &&
276 	    t1->bt.polarities == t2->bt.polarities &&
277 	    t1->bt.pixelclock >= t2->bt.pixelclock - pclock_delta &&
278 	    t1->bt.pixelclock <= t2->bt.pixelclock + pclock_delta &&
279 	    t1->bt.hfrontporch == t2->bt.hfrontporch &&
280 	    t1->bt.hsync == t2->bt.hsync &&
281 	    t1->bt.hbackporch == t2->bt.hbackporch &&
282 	    t1->bt.vfrontporch == t2->bt.vfrontporch &&
283 	    t1->bt.vsync == t2->bt.vsync &&
284 	    t1->bt.vbackporch == t2->bt.vbackporch &&
285 	    (!match_reduced_fps ||
286 	     (t1->bt.flags & V4L2_DV_FL_REDUCED_FPS) ==
287 		(t2->bt.flags & V4L2_DV_FL_REDUCED_FPS)) &&
288 	    (!t1->bt.interlaced ||
289 		(t1->bt.il_vfrontporch == t2->bt.il_vfrontporch &&
290 		 t1->bt.il_vsync == t2->bt.il_vsync &&
291 		 t1->bt.il_vbackporch == t2->bt.il_vbackporch)))
292 		return true;
293 	return false;
294 }
295 EXPORT_SYMBOL_GPL(v4l2_match_dv_timings);
296 
v4l2_print_dv_timings(const char * dev_prefix,const char * prefix,const struct v4l2_dv_timings * t,bool detailed)297 void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix,
298 			   const struct v4l2_dv_timings *t, bool detailed)
299 {
300 	const struct v4l2_bt_timings *bt = &t->bt;
301 	u32 htot, vtot;
302 	u32 fps;
303 
304 	if (t->type != V4L2_DV_BT_656_1120)
305 		return;
306 
307 	htot = V4L2_DV_BT_FRAME_WIDTH(bt);
308 	vtot = V4L2_DV_BT_FRAME_HEIGHT(bt);
309 	if (bt->interlaced)
310 		vtot /= 2;
311 
312 	fps = (htot * vtot) > 0 ? div_u64((100 * (u64)bt->pixelclock),
313 				  (htot * vtot)) : 0;
314 
315 	if (prefix == NULL)
316 		prefix = "";
317 
318 	pr_info("%s: %s%ux%u%s%u.%u (%ux%u)\n", dev_prefix, prefix,
319 		bt->width, bt->height, bt->interlaced ? "i" : "p",
320 		fps / 100, fps % 100, htot, vtot);
321 
322 	if (!detailed)
323 		return;
324 
325 	pr_info("%s: horizontal: fp = %u, %ssync = %u, bp = %u\n",
326 			dev_prefix, bt->hfrontporch,
327 			(bt->polarities & V4L2_DV_HSYNC_POS_POL) ? "+" : "-",
328 			bt->hsync, bt->hbackporch);
329 	pr_info("%s: vertical: fp = %u, %ssync = %u, bp = %u\n",
330 			dev_prefix, bt->vfrontporch,
331 			(bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
332 			bt->vsync, bt->vbackporch);
333 	if (bt->interlaced)
334 		pr_info("%s: vertical bottom field: fp = %u, %ssync = %u, bp = %u\n",
335 			dev_prefix, bt->il_vfrontporch,
336 			(bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
337 			bt->il_vsync, bt->il_vbackporch);
338 	pr_info("%s: pixelclock: %llu\n", dev_prefix, bt->pixelclock);
339 	pr_info("%s: flags (0x%x):%s%s%s%s%s%s%s%s%s%s\n",
340 			dev_prefix, bt->flags,
341 			(bt->flags & V4L2_DV_FL_REDUCED_BLANKING) ?
342 			" REDUCED_BLANKING" : "",
343 			((bt->flags & V4L2_DV_FL_REDUCED_BLANKING) &&
344 			 bt->vsync == 8) ? " (V2)" : "",
345 			(bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS) ?
346 			" CAN_REDUCE_FPS" : "",
347 			(bt->flags & V4L2_DV_FL_REDUCED_FPS) ?
348 			" REDUCED_FPS" : "",
349 			(bt->flags & V4L2_DV_FL_HALF_LINE) ?
350 			" HALF_LINE" : "",
351 			(bt->flags & V4L2_DV_FL_IS_CE_VIDEO) ?
352 			" CE_VIDEO" : "",
353 			(bt->flags & V4L2_DV_FL_FIRST_FIELD_EXTRA_LINE) ?
354 			" FIRST_FIELD_EXTRA_LINE" : "",
355 			(bt->flags & V4L2_DV_FL_HAS_PICTURE_ASPECT) ?
356 			" HAS_PICTURE_ASPECT" : "",
357 			(bt->flags & V4L2_DV_FL_HAS_CEA861_VIC) ?
358 			" HAS_CEA861_VIC" : "",
359 			(bt->flags & V4L2_DV_FL_HAS_HDMI_VIC) ?
360 			" HAS_HDMI_VIC" : "");
361 	pr_info("%s: standards (0x%x):%s%s%s%s%s\n", dev_prefix, bt->standards,
362 			(bt->standards & V4L2_DV_BT_STD_CEA861) ?  " CEA" : "",
363 			(bt->standards & V4L2_DV_BT_STD_DMT) ?  " DMT" : "",
364 			(bt->standards & V4L2_DV_BT_STD_CVT) ?  " CVT" : "",
365 			(bt->standards & V4L2_DV_BT_STD_GTF) ?  " GTF" : "",
366 			(bt->standards & V4L2_DV_BT_STD_SDI) ?  " SDI" : "");
367 	if (bt->flags & V4L2_DV_FL_HAS_PICTURE_ASPECT)
368 		pr_info("%s: picture aspect (hor:vert): %u:%u\n", dev_prefix,
369 			bt->picture_aspect.numerator,
370 			bt->picture_aspect.denominator);
371 	if (bt->flags & V4L2_DV_FL_HAS_CEA861_VIC)
372 		pr_info("%s: CEA-861 VIC: %u\n", dev_prefix, bt->cea861_vic);
373 	if (bt->flags & V4L2_DV_FL_HAS_HDMI_VIC)
374 		pr_info("%s: HDMI VIC: %u\n", dev_prefix, bt->hdmi_vic);
375 }
376 EXPORT_SYMBOL_GPL(v4l2_print_dv_timings);
377 
v4l2_dv_timings_aspect_ratio(const struct v4l2_dv_timings * t)378 struct v4l2_fract v4l2_dv_timings_aspect_ratio(const struct v4l2_dv_timings *t)
379 {
380 	struct v4l2_fract ratio = { 1, 1 };
381 	unsigned long n, d;
382 
383 	if (t->type != V4L2_DV_BT_656_1120)
384 		return ratio;
385 	if (!(t->bt.flags & V4L2_DV_FL_HAS_PICTURE_ASPECT))
386 		return ratio;
387 
388 	ratio.numerator = t->bt.width * t->bt.picture_aspect.denominator;
389 	ratio.denominator = t->bt.height * t->bt.picture_aspect.numerator;
390 
391 	rational_best_approximation(ratio.numerator, ratio.denominator,
392 				    ratio.numerator, ratio.denominator, &n, &d);
393 	ratio.numerator = n;
394 	ratio.denominator = d;
395 	return ratio;
396 }
397 EXPORT_SYMBOL_GPL(v4l2_dv_timings_aspect_ratio);
398 
399 /*
400  * CVT defines
401  * Based on Coordinated Video Timings Standard
402  * version 1.1 September 10, 2003
403  */
404 
405 #define CVT_PXL_CLK_GRAN	250000	/* pixel clock granularity */
406 #define CVT_PXL_CLK_GRAN_RB_V2 1000	/* granularity for reduced blanking v2*/
407 
408 /* Normal blanking */
409 #define CVT_MIN_V_BPORCH	7	/* lines */
410 #define CVT_MIN_V_PORCH_RND	3	/* lines */
411 #define CVT_MIN_VSYNC_BP	550	/* min time of vsync + back porch (us) */
412 #define CVT_HSYNC_PERCENT       8       /* nominal hsync as percentage of line */
413 
414 /* Normal blanking for CVT uses GTF to calculate horizontal blanking */
415 #define CVT_CELL_GRAN		8	/* character cell granularity */
416 #define CVT_M			600	/* blanking formula gradient */
417 #define CVT_C			40	/* blanking formula offset */
418 #define CVT_K			128	/* blanking formula scaling factor */
419 #define CVT_J			20	/* blanking formula scaling factor */
420 #define CVT_C_PRIME (((CVT_C - CVT_J) * CVT_K / 256) + CVT_J)
421 #define CVT_M_PRIME (CVT_K * CVT_M / 256)
422 
423 /* Reduced Blanking */
424 #define CVT_RB_MIN_V_BPORCH    7       /* lines  */
425 #define CVT_RB_V_FPORCH        3       /* lines  */
426 #define CVT_RB_MIN_V_BLANK   460       /* us     */
427 #define CVT_RB_H_SYNC         32       /* pixels */
428 #define CVT_RB_H_BLANK       160       /* pixels */
429 /* Reduce blanking Version 2 */
430 #define CVT_RB_V2_H_BLANK     80       /* pixels */
431 #define CVT_RB_MIN_V_FPORCH    3       /* lines  */
432 #define CVT_RB_V2_MIN_V_FPORCH 1       /* lines  */
433 #define CVT_RB_V_BPORCH        6       /* lines  */
434 
435 /** v4l2_detect_cvt - detect if the given timings follow the CVT standard
436  * @frame_height - the total height of the frame (including blanking) in lines.
437  * @hfreq - the horizontal frequency in Hz.
438  * @vsync - the height of the vertical sync in lines.
439  * @active_width - active width of image (does not include blanking). This
440  * information is needed only in case of version 2 of reduced blanking.
441  * In other cases, this parameter does not have any effect on timings.
442  * @polarities - the horizontal and vertical polarities (same as struct
443  *		v4l2_bt_timings polarities).
444  * @interlaced - if this flag is true, it indicates interlaced format
445  * @fmt - the resulting timings.
446  *
447  * This function will attempt to detect if the given values correspond to a
448  * valid CVT format. If so, then it will return true, and fmt will be filled
449  * in with the found CVT timings.
450  */
v4l2_detect_cvt(unsigned frame_height,unsigned hfreq,unsigned vsync,unsigned active_width,u32 polarities,bool interlaced,struct v4l2_dv_timings * fmt)451 bool v4l2_detect_cvt(unsigned frame_height,
452 		     unsigned hfreq,
453 		     unsigned vsync,
454 		     unsigned active_width,
455 		     u32 polarities,
456 		     bool interlaced,
457 		     struct v4l2_dv_timings *fmt)
458 {
459 	int  v_fp, v_bp, h_fp, h_bp, hsync;
460 	int  frame_width, image_height, image_width;
461 	bool reduced_blanking;
462 	bool rb_v2 = false;
463 	unsigned pix_clk;
464 
465 	if (vsync < 4 || vsync > 8)
466 		return false;
467 
468 	if (polarities == V4L2_DV_VSYNC_POS_POL)
469 		reduced_blanking = false;
470 	else if (polarities == V4L2_DV_HSYNC_POS_POL)
471 		reduced_blanking = true;
472 	else
473 		return false;
474 
475 	if (reduced_blanking && vsync == 8)
476 		rb_v2 = true;
477 
478 	if (rb_v2 && active_width == 0)
479 		return false;
480 
481 	if (!rb_v2 && vsync > 7)
482 		return false;
483 
484 	if (hfreq == 0)
485 		return false;
486 
487 	/* Vertical */
488 	if (reduced_blanking) {
489 		if (rb_v2) {
490 			v_bp = CVT_RB_V_BPORCH;
491 			v_fp = (CVT_RB_MIN_V_BLANK * hfreq) / 1000000 + 1;
492 			v_fp -= vsync + v_bp;
493 
494 			if (v_fp < CVT_RB_V2_MIN_V_FPORCH)
495 				v_fp = CVT_RB_V2_MIN_V_FPORCH;
496 		} else {
497 			v_fp = CVT_RB_V_FPORCH;
498 			v_bp = (CVT_RB_MIN_V_BLANK * hfreq) / 1000000 + 1;
499 			v_bp -= vsync + v_fp;
500 
501 			if (v_bp < CVT_RB_MIN_V_BPORCH)
502 				v_bp = CVT_RB_MIN_V_BPORCH;
503 		}
504 	} else {
505 		v_fp = CVT_MIN_V_PORCH_RND;
506 		v_bp = (CVT_MIN_VSYNC_BP * hfreq) / 1000000 + 1 - vsync;
507 
508 		if (v_bp < CVT_MIN_V_BPORCH)
509 			v_bp = CVT_MIN_V_BPORCH;
510 	}
511 
512 	if (interlaced)
513 		image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1;
514 	else
515 		image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
516 
517 	if (image_height < 0)
518 		return false;
519 
520 	/* Aspect ratio based on vsync */
521 	switch (vsync) {
522 	case 4:
523 		image_width = (image_height * 4) / 3;
524 		break;
525 	case 5:
526 		image_width = (image_height * 16) / 9;
527 		break;
528 	case 6:
529 		image_width = (image_height * 16) / 10;
530 		break;
531 	case 7:
532 		/* special case */
533 		if (image_height == 1024)
534 			image_width = (image_height * 5) / 4;
535 		else if (image_height == 768)
536 			image_width = (image_height * 15) / 9;
537 		else
538 			return false;
539 		break;
540 	case 8:
541 		image_width = active_width;
542 		break;
543 	default:
544 		return false;
545 	}
546 
547 	if (!rb_v2)
548 		image_width = image_width & ~7;
549 
550 	/* Horizontal */
551 	if (reduced_blanking) {
552 		int h_blank;
553 		int clk_gran;
554 
555 		h_blank = rb_v2 ? CVT_RB_V2_H_BLANK : CVT_RB_H_BLANK;
556 		clk_gran = rb_v2 ? CVT_PXL_CLK_GRAN_RB_V2 : CVT_PXL_CLK_GRAN;
557 
558 		pix_clk = (image_width + h_blank) * hfreq;
559 		pix_clk = (pix_clk / clk_gran) * clk_gran;
560 
561 		h_bp  = h_blank / 2;
562 		hsync = CVT_RB_H_SYNC;
563 		h_fp  = h_blank - h_bp - hsync;
564 
565 		frame_width = image_width + h_blank;
566 	} else {
567 		unsigned ideal_duty_cycle_per_myriad =
568 			100 * CVT_C_PRIME - (CVT_M_PRIME * 100000) / hfreq;
569 		int h_blank;
570 
571 		if (ideal_duty_cycle_per_myriad < 2000)
572 			ideal_duty_cycle_per_myriad = 2000;
573 
574 		h_blank = image_width * ideal_duty_cycle_per_myriad /
575 					(10000 - ideal_duty_cycle_per_myriad);
576 		h_blank = (h_blank / (2 * CVT_CELL_GRAN)) * 2 * CVT_CELL_GRAN;
577 
578 		pix_clk = (image_width + h_blank) * hfreq;
579 		pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
580 
581 		h_bp = h_blank / 2;
582 		frame_width = image_width + h_blank;
583 
584 		hsync = frame_width * CVT_HSYNC_PERCENT / 100;
585 		hsync = (hsync / CVT_CELL_GRAN) * CVT_CELL_GRAN;
586 		h_fp = h_blank - hsync - h_bp;
587 	}
588 
589 	fmt->type = V4L2_DV_BT_656_1120;
590 	fmt->bt.polarities = polarities;
591 	fmt->bt.width = image_width;
592 	fmt->bt.height = image_height;
593 	fmt->bt.hfrontporch = h_fp;
594 	fmt->bt.vfrontporch = v_fp;
595 	fmt->bt.hsync = hsync;
596 	fmt->bt.vsync = vsync;
597 	fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
598 
599 	if (!interlaced) {
600 		fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
601 		fmt->bt.interlaced = V4L2_DV_PROGRESSIVE;
602 	} else {
603 		fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp -
604 				      2 * vsync) / 2;
605 		fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp -
606 					2 * vsync - fmt->bt.vbackporch;
607 		fmt->bt.il_vfrontporch = v_fp;
608 		fmt->bt.il_vsync = vsync;
609 		fmt->bt.flags |= V4L2_DV_FL_HALF_LINE;
610 		fmt->bt.interlaced = V4L2_DV_INTERLACED;
611 	}
612 
613 	fmt->bt.pixelclock = pix_clk;
614 	fmt->bt.standards = V4L2_DV_BT_STD_CVT;
615 
616 	if (reduced_blanking)
617 		fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
618 
619 	return true;
620 }
621 EXPORT_SYMBOL_GPL(v4l2_detect_cvt);
622 
623 /*
624  * GTF defines
625  * Based on Generalized Timing Formula Standard
626  * Version 1.1 September 2, 1999
627  */
628 
629 #define GTF_PXL_CLK_GRAN	250000	/* pixel clock granularity */
630 
631 #define GTF_MIN_VSYNC_BP	550	/* min time of vsync + back porch (us) */
632 #define GTF_V_FP		1	/* vertical front porch (lines) */
633 #define GTF_CELL_GRAN		8	/* character cell granularity */
634 
635 /* Default */
636 #define GTF_D_M			600	/* blanking formula gradient */
637 #define GTF_D_C			40	/* blanking formula offset */
638 #define GTF_D_K			128	/* blanking formula scaling factor */
639 #define GTF_D_J			20	/* blanking formula scaling factor */
640 #define GTF_D_C_PRIME ((((GTF_D_C - GTF_D_J) * GTF_D_K) / 256) + GTF_D_J)
641 #define GTF_D_M_PRIME ((GTF_D_K * GTF_D_M) / 256)
642 
643 /* Secondary */
644 #define GTF_S_M			3600	/* blanking formula gradient */
645 #define GTF_S_C			40	/* blanking formula offset */
646 #define GTF_S_K			128	/* blanking formula scaling factor */
647 #define GTF_S_J			35	/* blanking formula scaling factor */
648 #define GTF_S_C_PRIME ((((GTF_S_C - GTF_S_J) * GTF_S_K) / 256) + GTF_S_J)
649 #define GTF_S_M_PRIME ((GTF_S_K * GTF_S_M) / 256)
650 
651 /** v4l2_detect_gtf - detect if the given timings follow the GTF standard
652  * @frame_height - the total height of the frame (including blanking) in lines.
653  * @hfreq - the horizontal frequency in Hz.
654  * @vsync - the height of the vertical sync in lines.
655  * @polarities - the horizontal and vertical polarities (same as struct
656  *		v4l2_bt_timings polarities).
657  * @interlaced - if this flag is true, it indicates interlaced format
658  * @aspect - preferred aspect ratio. GTF has no method of determining the
659  *		aspect ratio in order to derive the image width from the
660  *		image height, so it has to be passed explicitly. Usually
661  *		the native screen aspect ratio is used for this. If it
662  *		is not filled in correctly, then 16:9 will be assumed.
663  * @fmt - the resulting timings.
664  *
665  * This function will attempt to detect if the given values correspond to a
666  * valid GTF format. If so, then it will return true, and fmt will be filled
667  * in with the found GTF timings.
668  */
v4l2_detect_gtf(unsigned frame_height,unsigned hfreq,unsigned vsync,u32 polarities,bool interlaced,struct v4l2_fract aspect,struct v4l2_dv_timings * fmt)669 bool v4l2_detect_gtf(unsigned frame_height,
670 		unsigned hfreq,
671 		unsigned vsync,
672 		u32 polarities,
673 		bool interlaced,
674 		struct v4l2_fract aspect,
675 		struct v4l2_dv_timings *fmt)
676 {
677 	int pix_clk;
678 	int  v_fp, v_bp, h_fp, hsync;
679 	int frame_width, image_height, image_width;
680 	bool default_gtf;
681 	int h_blank;
682 
683 	if (vsync != 3)
684 		return false;
685 
686 	if (polarities == V4L2_DV_VSYNC_POS_POL)
687 		default_gtf = true;
688 	else if (polarities == V4L2_DV_HSYNC_POS_POL)
689 		default_gtf = false;
690 	else
691 		return false;
692 
693 	if (hfreq == 0)
694 		return false;
695 
696 	/* Vertical */
697 	v_fp = GTF_V_FP;
698 	v_bp = (GTF_MIN_VSYNC_BP * hfreq + 500000) / 1000000 - vsync;
699 	if (interlaced)
700 		image_height = (frame_height - 2 * v_fp - 2 * vsync - 2 * v_bp) & ~0x1;
701 	else
702 		image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
703 
704 	if (image_height < 0)
705 		return false;
706 
707 	if (aspect.numerator == 0 || aspect.denominator == 0) {
708 		aspect.numerator = 16;
709 		aspect.denominator = 9;
710 	}
711 	image_width = ((image_height * aspect.numerator) / aspect.denominator);
712 	image_width = (image_width + GTF_CELL_GRAN/2) & ~(GTF_CELL_GRAN - 1);
713 
714 	/* Horizontal */
715 	if (default_gtf) {
716 		u64 num;
717 		u32 den;
718 
719 		num = ((image_width * GTF_D_C_PRIME * (u64)hfreq) -
720 		      ((u64)image_width * GTF_D_M_PRIME * 1000));
721 		den = (hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) *
722 		      (2 * GTF_CELL_GRAN);
723 		h_blank = div_u64((num + (den >> 1)), den);
724 		h_blank *= (2 * GTF_CELL_GRAN);
725 	} else {
726 		u64 num;
727 		u32 den;
728 
729 		num = ((image_width * GTF_S_C_PRIME * (u64)hfreq) -
730 		      ((u64)image_width * GTF_S_M_PRIME * 1000));
731 		den = (hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) *
732 		      (2 * GTF_CELL_GRAN);
733 		h_blank = div_u64((num + (den >> 1)), den);
734 		h_blank *= (2 * GTF_CELL_GRAN);
735 	}
736 
737 	frame_width = image_width + h_blank;
738 
739 	pix_clk = (image_width + h_blank) * hfreq;
740 	pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN;
741 
742 	hsync = (frame_width * 8 + 50) / 100;
743 	hsync = ((hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN) * GTF_CELL_GRAN;
744 
745 	h_fp = h_blank / 2 - hsync;
746 
747 	fmt->type = V4L2_DV_BT_656_1120;
748 	fmt->bt.polarities = polarities;
749 	fmt->bt.width = image_width;
750 	fmt->bt.height = image_height;
751 	fmt->bt.hfrontporch = h_fp;
752 	fmt->bt.vfrontporch = v_fp;
753 	fmt->bt.hsync = hsync;
754 	fmt->bt.vsync = vsync;
755 	fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
756 
757 	if (!interlaced) {
758 		fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
759 		fmt->bt.interlaced = V4L2_DV_PROGRESSIVE;
760 	} else {
761 		fmt->bt.vbackporch = (frame_height - image_height - 2 * v_fp -
762 				      2 * vsync) / 2;
763 		fmt->bt.il_vbackporch = frame_height - image_height - 2 * v_fp -
764 					2 * vsync - fmt->bt.vbackporch;
765 		fmt->bt.il_vfrontporch = v_fp;
766 		fmt->bt.il_vsync = vsync;
767 		fmt->bt.flags |= V4L2_DV_FL_HALF_LINE;
768 		fmt->bt.interlaced = V4L2_DV_INTERLACED;
769 	}
770 
771 	fmt->bt.pixelclock = pix_clk;
772 	fmt->bt.standards = V4L2_DV_BT_STD_GTF;
773 
774 	if (!default_gtf)
775 		fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
776 
777 	return true;
778 }
779 EXPORT_SYMBOL_GPL(v4l2_detect_gtf);
780 
781 /** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
782  *	0x15 and 0x16 from the EDID.
783  * @hor_landscape - byte 0x15 from the EDID.
784  * @vert_portrait - byte 0x16 from the EDID.
785  *
786  * Determines the aspect ratio from the EDID.
787  * See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
788  * "Horizontal and Vertical Screen Size or Aspect Ratio"
789  */
v4l2_calc_aspect_ratio(u8 hor_landscape,u8 vert_portrait)790 struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait)
791 {
792 	struct v4l2_fract aspect = { 16, 9 };
793 	u8 ratio;
794 
795 	/* Nothing filled in, fallback to 16:9 */
796 	if (!hor_landscape && !vert_portrait)
797 		return aspect;
798 	/* Both filled in, so they are interpreted as the screen size in cm */
799 	if (hor_landscape && vert_portrait) {
800 		aspect.numerator = hor_landscape;
801 		aspect.denominator = vert_portrait;
802 		return aspect;
803 	}
804 	/* Only one is filled in, so interpret them as a ratio:
805 	   (val + 99) / 100 */
806 	ratio = hor_landscape | vert_portrait;
807 	/* Change some rounded values into the exact aspect ratio */
808 	if (ratio == 79) {
809 		aspect.numerator = 16;
810 		aspect.denominator = 9;
811 	} else if (ratio == 34) {
812 		aspect.numerator = 4;
813 		aspect.denominator = 3;
814 	} else if (ratio == 68) {
815 		aspect.numerator = 15;
816 		aspect.denominator = 9;
817 	} else {
818 		aspect.numerator = hor_landscape + 99;
819 		aspect.denominator = 100;
820 	}
821 	if (hor_landscape)
822 		return aspect;
823 	/* The aspect ratio is for portrait, so swap numerator and denominator */
824 	swap(aspect.denominator, aspect.numerator);
825 	return aspect;
826 }
827 EXPORT_SYMBOL_GPL(v4l2_calc_aspect_ratio);
828 
829 /** v4l2_hdmi_rx_colorimetry - determine HDMI colorimetry information
830  *	based on various InfoFrames.
831  * @avi: the AVI InfoFrame
832  * @hdmi: the HDMI Vendor InfoFrame, may be NULL
833  * @height: the frame height
834  *
835  * Determines the HDMI colorimetry information, i.e. how the HDMI
836  * pixel color data should be interpreted.
837  *
838  * Note that some of the newer features (DCI-P3, HDR) are not yet
839  * implemented: the hdmi.h header needs to be updated to the HDMI 2.0
840  * and CTA-861-G standards.
841  */
842 struct v4l2_hdmi_colorimetry
v4l2_hdmi_rx_colorimetry(const struct hdmi_avi_infoframe * avi,const struct hdmi_vendor_infoframe * hdmi,unsigned int height)843 v4l2_hdmi_rx_colorimetry(const struct hdmi_avi_infoframe *avi,
844 			 const struct hdmi_vendor_infoframe *hdmi,
845 			 unsigned int height)
846 {
847 	struct v4l2_hdmi_colorimetry c = {
848 		V4L2_COLORSPACE_SRGB,
849 		V4L2_YCBCR_ENC_DEFAULT,
850 		V4L2_QUANTIZATION_FULL_RANGE,
851 		V4L2_XFER_FUNC_SRGB
852 	};
853 	bool is_ce = avi->video_code || (hdmi && hdmi->vic);
854 	bool is_sdtv = height <= 576;
855 	bool default_is_lim_range_rgb = avi->video_code > 1;
856 
857 	switch (avi->colorspace) {
858 	case HDMI_COLORSPACE_RGB:
859 		/* RGB pixel encoding */
860 		switch (avi->colorimetry) {
861 		case HDMI_COLORIMETRY_EXTENDED:
862 			switch (avi->extended_colorimetry) {
863 			case HDMI_EXTENDED_COLORIMETRY_OPRGB:
864 				c.colorspace = V4L2_COLORSPACE_OPRGB;
865 				c.xfer_func = V4L2_XFER_FUNC_OPRGB;
866 				break;
867 			case HDMI_EXTENDED_COLORIMETRY_BT2020:
868 				c.colorspace = V4L2_COLORSPACE_BT2020;
869 				c.xfer_func = V4L2_XFER_FUNC_709;
870 				break;
871 			default:
872 				break;
873 			}
874 			break;
875 		default:
876 			break;
877 		}
878 		switch (avi->quantization_range) {
879 		case HDMI_QUANTIZATION_RANGE_LIMITED:
880 			c.quantization = V4L2_QUANTIZATION_LIM_RANGE;
881 			break;
882 		case HDMI_QUANTIZATION_RANGE_FULL:
883 			break;
884 		default:
885 			if (default_is_lim_range_rgb)
886 				c.quantization = V4L2_QUANTIZATION_LIM_RANGE;
887 			break;
888 		}
889 		break;
890 
891 	default:
892 		/* YCbCr pixel encoding */
893 		c.quantization = V4L2_QUANTIZATION_LIM_RANGE;
894 		switch (avi->colorimetry) {
895 		case HDMI_COLORIMETRY_NONE:
896 			if (!is_ce)
897 				break;
898 			if (is_sdtv) {
899 				c.colorspace = V4L2_COLORSPACE_SMPTE170M;
900 				c.ycbcr_enc = V4L2_YCBCR_ENC_601;
901 			} else {
902 				c.colorspace = V4L2_COLORSPACE_REC709;
903 				c.ycbcr_enc = V4L2_YCBCR_ENC_709;
904 			}
905 			c.xfer_func = V4L2_XFER_FUNC_709;
906 			break;
907 		case HDMI_COLORIMETRY_ITU_601:
908 			c.colorspace = V4L2_COLORSPACE_SMPTE170M;
909 			c.ycbcr_enc = V4L2_YCBCR_ENC_601;
910 			c.xfer_func = V4L2_XFER_FUNC_709;
911 			break;
912 		case HDMI_COLORIMETRY_ITU_709:
913 			c.colorspace = V4L2_COLORSPACE_REC709;
914 			c.ycbcr_enc = V4L2_YCBCR_ENC_709;
915 			c.xfer_func = V4L2_XFER_FUNC_709;
916 			break;
917 		case HDMI_COLORIMETRY_EXTENDED:
918 			switch (avi->extended_colorimetry) {
919 			case HDMI_EXTENDED_COLORIMETRY_XV_YCC_601:
920 				c.colorspace = V4L2_COLORSPACE_REC709;
921 				c.ycbcr_enc = V4L2_YCBCR_ENC_XV709;
922 				c.xfer_func = V4L2_XFER_FUNC_709;
923 				break;
924 			case HDMI_EXTENDED_COLORIMETRY_XV_YCC_709:
925 				c.colorspace = V4L2_COLORSPACE_REC709;
926 				c.ycbcr_enc = V4L2_YCBCR_ENC_XV601;
927 				c.xfer_func = V4L2_XFER_FUNC_709;
928 				break;
929 			case HDMI_EXTENDED_COLORIMETRY_S_YCC_601:
930 				c.colorspace = V4L2_COLORSPACE_SRGB;
931 				c.ycbcr_enc = V4L2_YCBCR_ENC_601;
932 				c.xfer_func = V4L2_XFER_FUNC_SRGB;
933 				break;
934 			case HDMI_EXTENDED_COLORIMETRY_OPYCC_601:
935 				c.colorspace = V4L2_COLORSPACE_OPRGB;
936 				c.ycbcr_enc = V4L2_YCBCR_ENC_601;
937 				c.xfer_func = V4L2_XFER_FUNC_OPRGB;
938 				break;
939 			case HDMI_EXTENDED_COLORIMETRY_BT2020:
940 				c.colorspace = V4L2_COLORSPACE_BT2020;
941 				c.ycbcr_enc = V4L2_YCBCR_ENC_BT2020;
942 				c.xfer_func = V4L2_XFER_FUNC_709;
943 				break;
944 			case HDMI_EXTENDED_COLORIMETRY_BT2020_CONST_LUM:
945 				c.colorspace = V4L2_COLORSPACE_BT2020;
946 				c.ycbcr_enc = V4L2_YCBCR_ENC_BT2020_CONST_LUM;
947 				c.xfer_func = V4L2_XFER_FUNC_709;
948 				break;
949 			default: /* fall back to ITU_709 */
950 				c.colorspace = V4L2_COLORSPACE_REC709;
951 				c.ycbcr_enc = V4L2_YCBCR_ENC_709;
952 				c.xfer_func = V4L2_XFER_FUNC_709;
953 				break;
954 			}
955 			break;
956 		default:
957 			break;
958 		}
959 		/*
960 		 * YCC Quantization Range signaling is more-or-less broken,
961 		 * let's just ignore this.
962 		 */
963 		break;
964 	}
965 	return c;
966 }
967 EXPORT_SYMBOL_GPL(v4l2_hdmi_rx_colorimetry);
968 
969 /**
970  * v4l2_get_edid_phys_addr() - find and return the physical address
971  *
972  * @edid:	pointer to the EDID data
973  * @size:	size in bytes of the EDID data
974  * @offset:	If not %NULL then the location of the physical address
975  *		bytes in the EDID will be returned here. This is set to 0
976  *		if there is no physical address found.
977  *
978  * Return: the physical address or CEC_PHYS_ADDR_INVALID if there is none.
979  */
v4l2_get_edid_phys_addr(const u8 * edid,unsigned int size,unsigned int * offset)980 u16 v4l2_get_edid_phys_addr(const u8 *edid, unsigned int size,
981 			    unsigned int *offset)
982 {
983 	unsigned int loc = cec_get_edid_spa_location(edid, size);
984 
985 	if (offset)
986 		*offset = loc;
987 	if (loc == 0)
988 		return CEC_PHYS_ADDR_INVALID;
989 	return (edid[loc] << 8) | edid[loc + 1];
990 }
991 EXPORT_SYMBOL_GPL(v4l2_get_edid_phys_addr);
992 
993 /**
994  * v4l2_set_edid_phys_addr() - find and set the physical address
995  *
996  * @edid:	pointer to the EDID data
997  * @size:	size in bytes of the EDID data
998  * @phys_addr:	the new physical address
999  *
1000  * This function finds the location of the physical address in the EDID
1001  * and fills in the given physical address and updates the checksum
1002  * at the end of the EDID block. It does nothing if the EDID doesn't
1003  * contain a physical address.
1004  */
v4l2_set_edid_phys_addr(u8 * edid,unsigned int size,u16 phys_addr)1005 void v4l2_set_edid_phys_addr(u8 *edid, unsigned int size, u16 phys_addr)
1006 {
1007 	unsigned int loc = cec_get_edid_spa_location(edid, size);
1008 	u8 sum = 0;
1009 	unsigned int i;
1010 
1011 	if (loc == 0)
1012 		return;
1013 	edid[loc] = phys_addr >> 8;
1014 	edid[loc + 1] = phys_addr & 0xff;
1015 	loc &= ~0x7f;
1016 
1017 	/* update the checksum */
1018 	for (i = loc; i < loc + 127; i++)
1019 		sum += edid[i];
1020 	edid[i] = 256 - sum;
1021 }
1022 EXPORT_SYMBOL_GPL(v4l2_set_edid_phys_addr);
1023 
1024 /**
1025  * v4l2_phys_addr_for_input() - calculate the PA for an input
1026  *
1027  * @phys_addr:	the physical address of the parent
1028  * @input:	the number of the input port, must be between 1 and 15
1029  *
1030  * This function calculates a new physical address based on the input
1031  * port number. For example:
1032  *
1033  * PA = 0.0.0.0 and input = 2 becomes 2.0.0.0
1034  *
1035  * PA = 3.0.0.0 and input = 1 becomes 3.1.0.0
1036  *
1037  * PA = 3.2.1.0 and input = 5 becomes 3.2.1.5
1038  *
1039  * PA = 3.2.1.3 and input = 5 becomes f.f.f.f since it maxed out the depth.
1040  *
1041  * Return: the new physical address or CEC_PHYS_ADDR_INVALID.
1042  */
v4l2_phys_addr_for_input(u16 phys_addr,u8 input)1043 u16 v4l2_phys_addr_for_input(u16 phys_addr, u8 input)
1044 {
1045 	/* Check if input is sane */
1046 	if (WARN_ON(input == 0 || input > 0xf))
1047 		return CEC_PHYS_ADDR_INVALID;
1048 
1049 	if (phys_addr == 0)
1050 		return input << 12;
1051 
1052 	if ((phys_addr & 0x0fff) == 0)
1053 		return phys_addr | (input << 8);
1054 
1055 	if ((phys_addr & 0x00ff) == 0)
1056 		return phys_addr | (input << 4);
1057 
1058 	if ((phys_addr & 0x000f) == 0)
1059 		return phys_addr | input;
1060 
1061 	/*
1062 	 * All nibbles are used so no valid physical addresses can be assigned
1063 	 * to the input.
1064 	 */
1065 	return CEC_PHYS_ADDR_INVALID;
1066 }
1067 EXPORT_SYMBOL_GPL(v4l2_phys_addr_for_input);
1068 
1069 /**
1070  * v4l2_phys_addr_validate() - validate a physical address from an EDID
1071  *
1072  * @phys_addr:	the physical address to validate
1073  * @parent:	if not %NULL, then this is filled with the parents PA.
1074  * @port:	if not %NULL, then this is filled with the input port.
1075  *
1076  * This validates a physical address as read from an EDID. If the
1077  * PA is invalid (such as 1.0.1.0 since '0' is only allowed at the end),
1078  * then it will return -EINVAL.
1079  *
1080  * The parent PA is passed into %parent and the input port is passed into
1081  * %port. For example:
1082  *
1083  * PA = 0.0.0.0: has parent 0.0.0.0 and input port 0.
1084  *
1085  * PA = 1.0.0.0: has parent 0.0.0.0 and input port 1.
1086  *
1087  * PA = 3.2.0.0: has parent 3.0.0.0 and input port 2.
1088  *
1089  * PA = f.f.f.f: has parent f.f.f.f and input port 0.
1090  *
1091  * Return: 0 if the PA is valid, -EINVAL if not.
1092  */
v4l2_phys_addr_validate(u16 phys_addr,u16 * parent,u16 * port)1093 int v4l2_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port)
1094 {
1095 	int i;
1096 
1097 	if (parent)
1098 		*parent = phys_addr;
1099 	if (port)
1100 		*port = 0;
1101 	if (phys_addr == CEC_PHYS_ADDR_INVALID)
1102 		return 0;
1103 	for (i = 0; i < 16; i += 4)
1104 		if (phys_addr & (0xf << i))
1105 			break;
1106 	if (i == 16)
1107 		return 0;
1108 	if (parent)
1109 		*parent = phys_addr & (0xfff0 << i);
1110 	if (port)
1111 		*port = (phys_addr >> i) & 0xf;
1112 	for (i += 4; i < 16; i += 4)
1113 		if ((phys_addr & (0xf << i)) == 0)
1114 			return -EINVAL;
1115 	return 0;
1116 }
1117 EXPORT_SYMBOL_GPL(v4l2_phys_addr_validate);
1118