xref: /openbmc/linux/drivers/video/hdmi.c (revision 5bd8e16d)
1 /*
2  * Copyright (C) 2012 Avionic Design GmbH
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sub license,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the
12  * next paragraph) shall be included in all copies or substantial portions
13  * of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21  * DEALINGS IN THE SOFTWARE.
22  */
23 
24 #include <linux/bitops.h>
25 #include <linux/bug.h>
26 #include <linux/errno.h>
27 #include <linux/export.h>
28 #include <linux/hdmi.h>
29 #include <linux/string.h>
30 
31 static void hdmi_infoframe_checksum(void *buffer, size_t size)
32 {
33 	u8 *ptr = buffer;
34 	u8 csum = 0;
35 	size_t i;
36 
37 	/* compute checksum */
38 	for (i = 0; i < size; i++)
39 		csum += ptr[i];
40 
41 	ptr[3] = 256 - csum;
42 }
43 
44 /**
45  * hdmi_avi_infoframe_init() - initialize an HDMI AVI infoframe
46  * @frame: HDMI AVI infoframe
47  *
48  * Returns 0 on success or a negative error code on failure.
49  */
50 int hdmi_avi_infoframe_init(struct hdmi_avi_infoframe *frame)
51 {
52 	memset(frame, 0, sizeof(*frame));
53 
54 	frame->type = HDMI_INFOFRAME_TYPE_AVI;
55 	frame->version = 2;
56 	frame->length = HDMI_AVI_INFOFRAME_SIZE;
57 
58 	return 0;
59 }
60 EXPORT_SYMBOL(hdmi_avi_infoframe_init);
61 
62 /**
63  * hdmi_avi_infoframe_pack() - write HDMI AVI infoframe to binary buffer
64  * @frame: HDMI AVI infoframe
65  * @buffer: destination buffer
66  * @size: size of buffer
67  *
68  * Packs the information contained in the @frame structure into a binary
69  * representation that can be written into the corresponding controller
70  * registers. Also computes the checksum as required by section 5.3.5 of
71  * the HDMI 1.4 specification.
72  *
73  * Returns the number of bytes packed into the binary buffer or a negative
74  * error code on failure.
75  */
76 ssize_t hdmi_avi_infoframe_pack(struct hdmi_avi_infoframe *frame, void *buffer,
77 				size_t size)
78 {
79 	u8 *ptr = buffer;
80 	size_t length;
81 
82 	length = HDMI_INFOFRAME_HEADER_SIZE + frame->length;
83 
84 	if (size < length)
85 		return -ENOSPC;
86 
87 	memset(buffer, 0, size);
88 
89 	ptr[0] = frame->type;
90 	ptr[1] = frame->version;
91 	ptr[2] = frame->length;
92 	ptr[3] = 0; /* checksum */
93 
94 	/* start infoframe payload */
95 	ptr += HDMI_INFOFRAME_HEADER_SIZE;
96 
97 	ptr[0] = ((frame->colorspace & 0x3) << 5) | (frame->scan_mode & 0x3);
98 
99 	/*
100 	 * Data byte 1, bit 4 has to be set if we provide the active format
101 	 * aspect ratio
102 	 */
103 	if (frame->active_aspect & 0xf)
104 		ptr[0] |= BIT(4);
105 
106 	/* Bit 3 and 2 indicate if we transmit horizontal/vertical bar data */
107 	if (frame->top_bar || frame->bottom_bar)
108 		ptr[0] |= BIT(3);
109 
110 	if (frame->left_bar || frame->right_bar)
111 		ptr[0] |= BIT(2);
112 
113 	ptr[1] = ((frame->colorimetry & 0x3) << 6) |
114 		 ((frame->picture_aspect & 0x3) << 4) |
115 		 (frame->active_aspect & 0xf);
116 
117 	ptr[2] = ((frame->extended_colorimetry & 0x7) << 4) |
118 		 ((frame->quantization_range & 0x3) << 2) |
119 		 (frame->nups & 0x3);
120 
121 	if (frame->itc)
122 		ptr[2] |= BIT(7);
123 
124 	ptr[3] = frame->video_code & 0x7f;
125 
126 	ptr[4] = ((frame->ycc_quantization_range & 0x3) << 6) |
127 		 ((frame->content_type & 0x3) << 4) |
128 		 (frame->pixel_repeat & 0xf);
129 
130 	ptr[5] = frame->top_bar & 0xff;
131 	ptr[6] = (frame->top_bar >> 8) & 0xff;
132 	ptr[7] = frame->bottom_bar & 0xff;
133 	ptr[8] = (frame->bottom_bar >> 8) & 0xff;
134 	ptr[9] = frame->left_bar & 0xff;
135 	ptr[10] = (frame->left_bar >> 8) & 0xff;
136 	ptr[11] = frame->right_bar & 0xff;
137 	ptr[12] = (frame->right_bar >> 8) & 0xff;
138 
139 	hdmi_infoframe_checksum(buffer, length);
140 
141 	return length;
142 }
143 EXPORT_SYMBOL(hdmi_avi_infoframe_pack);
144 
145 /**
146  * hdmi_spd_infoframe_init() - initialize an HDMI SPD infoframe
147  * @frame: HDMI SPD infoframe
148  * @vendor: vendor string
149  * @product: product string
150  *
151  * Returns 0 on success or a negative error code on failure.
152  */
153 int hdmi_spd_infoframe_init(struct hdmi_spd_infoframe *frame,
154 			    const char *vendor, const char *product)
155 {
156 	memset(frame, 0, sizeof(*frame));
157 
158 	frame->type = HDMI_INFOFRAME_TYPE_SPD;
159 	frame->version = 1;
160 	frame->length = HDMI_SPD_INFOFRAME_SIZE;
161 
162 	strncpy(frame->vendor, vendor, sizeof(frame->vendor));
163 	strncpy(frame->product, product, sizeof(frame->product));
164 
165 	return 0;
166 }
167 EXPORT_SYMBOL(hdmi_spd_infoframe_init);
168 
169 /**
170  * hdmi_spd_infoframe_pack() - write HDMI SPD infoframe to binary buffer
171  * @frame: HDMI SPD infoframe
172  * @buffer: destination buffer
173  * @size: size of buffer
174  *
175  * Packs the information contained in the @frame structure into a binary
176  * representation that can be written into the corresponding controller
177  * registers. Also computes the checksum as required by section 5.3.5 of
178  * the HDMI 1.4 specification.
179  *
180  * Returns the number of bytes packed into the binary buffer or a negative
181  * error code on failure.
182  */
183 ssize_t hdmi_spd_infoframe_pack(struct hdmi_spd_infoframe *frame, void *buffer,
184 				size_t size)
185 {
186 	u8 *ptr = buffer;
187 	size_t length;
188 
189 	length = HDMI_INFOFRAME_HEADER_SIZE + frame->length;
190 
191 	if (size < length)
192 		return -ENOSPC;
193 
194 	memset(buffer, 0, size);
195 
196 	ptr[0] = frame->type;
197 	ptr[1] = frame->version;
198 	ptr[2] = frame->length;
199 	ptr[3] = 0; /* checksum */
200 
201 	/* start infoframe payload */
202 	ptr += HDMI_INFOFRAME_HEADER_SIZE;
203 
204 	memcpy(ptr, frame->vendor, sizeof(frame->vendor));
205 	memcpy(ptr + 8, frame->product, sizeof(frame->product));
206 
207 	ptr[24] = frame->sdi;
208 
209 	hdmi_infoframe_checksum(buffer, length);
210 
211 	return length;
212 }
213 EXPORT_SYMBOL(hdmi_spd_infoframe_pack);
214 
215 /**
216  * hdmi_audio_infoframe_init() - initialize an HDMI audio infoframe
217  * @frame: HDMI audio infoframe
218  *
219  * Returns 0 on success or a negative error code on failure.
220  */
221 int hdmi_audio_infoframe_init(struct hdmi_audio_infoframe *frame)
222 {
223 	memset(frame, 0, sizeof(*frame));
224 
225 	frame->type = HDMI_INFOFRAME_TYPE_AUDIO;
226 	frame->version = 1;
227 	frame->length = HDMI_AUDIO_INFOFRAME_SIZE;
228 
229 	return 0;
230 }
231 EXPORT_SYMBOL(hdmi_audio_infoframe_init);
232 
233 /**
234  * hdmi_audio_infoframe_pack() - write HDMI audio infoframe to binary buffer
235  * @frame: HDMI audio infoframe
236  * @buffer: destination buffer
237  * @size: size of buffer
238  *
239  * Packs the information contained in the @frame structure into a binary
240  * representation that can be written into the corresponding controller
241  * registers. Also computes the checksum as required by section 5.3.5 of
242  * the HDMI 1.4 specification.
243  *
244  * Returns the number of bytes packed into the binary buffer or a negative
245  * error code on failure.
246  */
247 ssize_t hdmi_audio_infoframe_pack(struct hdmi_audio_infoframe *frame,
248 				  void *buffer, size_t size)
249 {
250 	unsigned char channels;
251 	u8 *ptr = buffer;
252 	size_t length;
253 
254 	length = HDMI_INFOFRAME_HEADER_SIZE + frame->length;
255 
256 	if (size < length)
257 		return -ENOSPC;
258 
259 	memset(buffer, 0, size);
260 
261 	if (frame->channels >= 2)
262 		channels = frame->channels - 1;
263 	else
264 		channels = 0;
265 
266 	ptr[0] = frame->type;
267 	ptr[1] = frame->version;
268 	ptr[2] = frame->length;
269 	ptr[3] = 0; /* checksum */
270 
271 	/* start infoframe payload */
272 	ptr += HDMI_INFOFRAME_HEADER_SIZE;
273 
274 	ptr[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7);
275 	ptr[1] = ((frame->sample_frequency & 0x7) << 2) |
276 		 (frame->sample_size & 0x3);
277 	ptr[2] = frame->coding_type_ext & 0x1f;
278 	ptr[3] = frame->channel_allocation;
279 	ptr[4] = (frame->level_shift_value & 0xf) << 3;
280 
281 	if (frame->downmix_inhibit)
282 		ptr[4] |= BIT(7);
283 
284 	hdmi_infoframe_checksum(buffer, length);
285 
286 	return length;
287 }
288 EXPORT_SYMBOL(hdmi_audio_infoframe_pack);
289 
290 /**
291  * hdmi_vendor_infoframe_init() - initialize an HDMI vendor infoframe
292  * @frame: HDMI vendor infoframe
293  *
294  * Returns 0 on success or a negative error code on failure.
295  */
296 int hdmi_vendor_infoframe_init(struct hdmi_vendor_infoframe *frame)
297 {
298 	memset(frame, 0, sizeof(*frame));
299 
300 	frame->type = HDMI_INFOFRAME_TYPE_VENDOR;
301 	frame->version = 1;
302 
303 	frame->oui = HDMI_IEEE_OUI;
304 
305 	/*
306 	 * 0 is a valid value for s3d_struct, so we use a special "not set"
307 	 * value
308 	 */
309 	frame->s3d_struct = HDMI_3D_STRUCTURE_INVALID;
310 
311 	return 0;
312 }
313 EXPORT_SYMBOL(hdmi_vendor_infoframe_init);
314 
315 /**
316  * hdmi_vendor_infoframe_pack() - write a HDMI vendor infoframe to binary buffer
317  * @frame: HDMI infoframe
318  * @buffer: destination buffer
319  * @size: size of buffer
320  *
321  * Packs the information contained in the @frame structure into a binary
322  * representation that can be written into the corresponding controller
323  * registers. Also computes the checksum as required by section 5.3.5 of
324  * the HDMI 1.4 specification.
325  *
326  * Returns the number of bytes packed into the binary buffer or a negative
327  * error code on failure.
328  */
329 ssize_t hdmi_vendor_infoframe_pack(struct hdmi_vendor_infoframe *frame,
330 				 void *buffer, size_t size)
331 {
332 	u8 *ptr = buffer;
333 	size_t length;
334 
335 	/* empty info frame */
336 	if (frame->vic == 0 && frame->s3d_struct == HDMI_3D_STRUCTURE_INVALID)
337 		return -EINVAL;
338 
339 	/* only one of those can be supplied */
340 	if (frame->vic != 0 && frame->s3d_struct != HDMI_3D_STRUCTURE_INVALID)
341 		return -EINVAL;
342 
343 	/* for side by side (half) we also need to provide 3D_Ext_Data */
344 	if (frame->s3d_struct >= HDMI_3D_STRUCTURE_SIDE_BY_SIDE_HALF)
345 		frame->length = 6;
346 	else
347 		frame->length = 5;
348 
349 	length = HDMI_INFOFRAME_HEADER_SIZE + frame->length;
350 
351 	if (size < length)
352 		return -ENOSPC;
353 
354 	memset(buffer, 0, size);
355 
356 	ptr[0] = frame->type;
357 	ptr[1] = frame->version;
358 	ptr[2] = frame->length;
359 	ptr[3] = 0; /* checksum */
360 
361 	/* HDMI OUI */
362 	ptr[4] = 0x03;
363 	ptr[5] = 0x0c;
364 	ptr[6] = 0x00;
365 
366 	if (frame->vic) {
367 		ptr[7] = 0x1 << 5;	/* video format */
368 		ptr[8] = frame->vic;
369 	} else {
370 		ptr[7] = 0x2 << 5;	/* video format */
371 		ptr[8] = (frame->s3d_struct & 0xf) << 4;
372 		if (frame->s3d_struct >= HDMI_3D_STRUCTURE_SIDE_BY_SIDE_HALF)
373 			ptr[9] = (frame->s3d_ext_data & 0xf) << 4;
374 	}
375 
376 	hdmi_infoframe_checksum(buffer, length);
377 
378 	return length;
379 }
380 EXPORT_SYMBOL(hdmi_vendor_infoframe_pack);
381 
382 /*
383  * hdmi_vendor_any_infoframe_pack() - write a vendor infoframe to binary buffer
384  */
385 static ssize_t
386 hdmi_vendor_any_infoframe_pack(union hdmi_vendor_any_infoframe *frame,
387 			   void *buffer, size_t size)
388 {
389 	/* we only know about HDMI vendor infoframes */
390 	if (frame->any.oui != HDMI_IEEE_OUI)
391 		return -EINVAL;
392 
393 	return hdmi_vendor_infoframe_pack(&frame->hdmi, buffer, size);
394 }
395 
396 /**
397  * hdmi_infoframe_pack() - write a HDMI infoframe to binary buffer
398  * @frame: HDMI infoframe
399  * @buffer: destination buffer
400  * @size: size of buffer
401  *
402  * Packs the information contained in the @frame structure into a binary
403  * representation that can be written into the corresponding controller
404  * registers. Also computes the checksum as required by section 5.3.5 of
405  * the HDMI 1.4 specification.
406  *
407  * Returns the number of bytes packed into the binary buffer or a negative
408  * error code on failure.
409  */
410 ssize_t
411 hdmi_infoframe_pack(union hdmi_infoframe *frame, void *buffer, size_t size)
412 {
413 	ssize_t length;
414 
415 	switch (frame->any.type) {
416 	case HDMI_INFOFRAME_TYPE_AVI:
417 		length = hdmi_avi_infoframe_pack(&frame->avi, buffer, size);
418 		break;
419 	case HDMI_INFOFRAME_TYPE_SPD:
420 		length = hdmi_spd_infoframe_pack(&frame->spd, buffer, size);
421 		break;
422 	case HDMI_INFOFRAME_TYPE_AUDIO:
423 		length = hdmi_audio_infoframe_pack(&frame->audio, buffer, size);
424 		break;
425 	case HDMI_INFOFRAME_TYPE_VENDOR:
426 		length = hdmi_vendor_any_infoframe_pack(&frame->vendor,
427 							buffer, size);
428 		break;
429 	default:
430 		WARN(1, "Bad infoframe type %d\n", frame->any.type);
431 		length = -EINVAL;
432 	}
433 
434 	return length;
435 }
436 EXPORT_SYMBOL(hdmi_infoframe_pack);
437