pcm_drm_eld.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  PCM DRM helpers
  4 */
  5#include <linux/bitfield.h>
  6#include <linux/export.h>
  7#include <linux/hdmi.h>
  8#include <linux/unaligned.h>
  9#include <drm/drm_edid.h>
 10#include <drm/drm_eld.h>
 11#include <sound/info.h>
 12#include <sound/pcm.h>
 13#include <sound/pcm_drm_eld.h>
 14
 15#define SAD0_CHANNELS_MASK	GENMASK(2, 0) /* max number of channels - 1 */
 16#define SAD0_FORMAT_MASK	GENMASK(6, 3) /* audio format */
 17
 18#define SAD1_RATE_MASK		GENMASK(6, 0) /* bitfield of supported rates */
 19#define SAD1_RATE_32000_MASK	BIT(0)
 20#define SAD1_RATE_44100_MASK	BIT(1)
 21#define SAD1_RATE_48000_MASK	BIT(2)
 22#define SAD1_RATE_88200_MASK	BIT(3)
 23#define SAD1_RATE_96000_MASK	BIT(4)
 24#define SAD1_RATE_176400_MASK	BIT(5)
 25#define SAD1_RATE_192000_MASK	BIT(6)
 26
 27static const unsigned int eld_rates[] = {
 28	32000,
 29	44100,
 30	48000,
 31	88200,
 32	96000,
 33	176400,
 34	192000,
 35};
 36
 37static unsigned int map_rate_families(const u8 *sad,
 38				      unsigned int mask_32000,
 39				      unsigned int mask_44100,
 40				      unsigned int mask_48000)
 41{
 42	unsigned int rate_mask = 0;
 43
 44	if (sad[1] & SAD1_RATE_32000_MASK)
 45		rate_mask |= mask_32000;
 46	if (sad[1] & (SAD1_RATE_44100_MASK | SAD1_RATE_88200_MASK | SAD1_RATE_176400_MASK))
 47		rate_mask |= mask_44100;
 48	if (sad[1] & (SAD1_RATE_48000_MASK | SAD1_RATE_96000_MASK | SAD1_RATE_192000_MASK))
 49		rate_mask |= mask_48000;
 50	return rate_mask;
 51}
 52
 53static unsigned int sad_rate_mask(const u8 *sad)
 54{
 55	switch (FIELD_GET(SAD0_FORMAT_MASK, sad[0])) {
 56	case HDMI_AUDIO_CODING_TYPE_PCM:
 57		return sad[1] & SAD1_RATE_MASK;
 58	case HDMI_AUDIO_CODING_TYPE_AC3:
 59	case HDMI_AUDIO_CODING_TYPE_DTS:
 60		return map_rate_families(sad,
 61					 SAD1_RATE_32000_MASK,
 62					 SAD1_RATE_44100_MASK,
 63					 SAD1_RATE_48000_MASK);
 64	case HDMI_AUDIO_CODING_TYPE_EAC3:
 65	case HDMI_AUDIO_CODING_TYPE_DTS_HD:
 66	case HDMI_AUDIO_CODING_TYPE_MLP:
 67		return map_rate_families(sad,
 68					 0,
 69					 SAD1_RATE_176400_MASK,
 70					 SAD1_RATE_192000_MASK);
 71	default:
 72		/* TODO adjust for other compressed formats as well */
 73		return sad[1] & SAD1_RATE_MASK;
 74	}
 75}
 76
 77static unsigned int sad_max_channels(const u8 *sad)
 78{
 79	switch (FIELD_GET(SAD0_FORMAT_MASK, sad[0])) {
 80	case HDMI_AUDIO_CODING_TYPE_PCM:
 81		return 1 + FIELD_GET(SAD0_CHANNELS_MASK, sad[0]);
 82	case HDMI_AUDIO_CODING_TYPE_AC3:
 83	case HDMI_AUDIO_CODING_TYPE_DTS:
 84	case HDMI_AUDIO_CODING_TYPE_EAC3:
 85		return 2;
 86	case HDMI_AUDIO_CODING_TYPE_DTS_HD:
 87	case HDMI_AUDIO_CODING_TYPE_MLP:
 88		return 8;
 89	default:
 90		/* TODO adjust for other compressed formats as well */
 91		return 1 + FIELD_GET(SAD0_CHANNELS_MASK, sad[0]);
 92	}
 93}
 94
 95static int eld_limit_rates(struct snd_pcm_hw_params *params,
 96			   struct snd_pcm_hw_rule *rule)
 97{
 98	struct snd_interval *r = hw_param_interval(params, rule->var);
 99	const struct snd_interval *c;
100	unsigned int rate_mask = 7, i;
101	const u8 *sad, *eld = rule->private;
102
103	sad = drm_eld_sad(eld);
104	if (sad) {
105		c = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
106
107		for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3) {
108			unsigned max_channels = sad_max_channels(sad);
109
110			/*
111			 * Exclude SADs which do not include the
112			 * requested number of channels.
113			 */
114			if (c->min <= max_channels)
115				rate_mask |= sad_rate_mask(sad);
116		}
117	}
118
119	return snd_interval_list(r, ARRAY_SIZE(eld_rates), eld_rates,
120				 rate_mask);
121}
122
123static int eld_limit_channels(struct snd_pcm_hw_params *params,
124			      struct snd_pcm_hw_rule *rule)
125{
126	struct snd_interval *c = hw_param_interval(params, rule->var);
127	const struct snd_interval *r;
128	struct snd_interval t = { .min = 1, .max = 2, .integer = 1, };
129	unsigned int i;
130	const u8 *sad, *eld = rule->private;
131
132	sad = drm_eld_sad(eld);
133	if (sad) {
134		unsigned int rate_mask = 0;
135
136		/* Convert the rate interval to a mask */
137		r = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
138		for (i = 0; i < ARRAY_SIZE(eld_rates); i++)
139			if (r->min <= eld_rates[i] && r->max >= eld_rates[i])
140				rate_mask |= BIT(i);
141
142		for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3)
143			if (rate_mask & sad_rate_mask(sad))
144				t.max = max(t.max, sad_max_channels(sad));
145	}
146
147	return snd_interval_refine(c, &t);
148}
149
150int snd_pcm_hw_constraint_eld(struct snd_pcm_runtime *runtime, void *eld)
151{
152	int ret;
153
154	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
155				  eld_limit_rates, eld,
156				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
157	if (ret < 0)
158		return ret;
159
160	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
161				  eld_limit_channels, eld,
162				  SNDRV_PCM_HW_PARAM_RATE, -1);
163
164	return ret;
165}
166EXPORT_SYMBOL_GPL(snd_pcm_hw_constraint_eld);
167
168#define SND_PRINT_RATES_ADVISED_BUFSIZE	80
169#define SND_PRINT_BITS_ADVISED_BUFSIZE	16
170#define SND_PRINT_CHANNEL_ALLOCATION_ADVISED_BUFSIZE 80
171
172static const char * const eld_connection_type_names[4] = {
173	"HDMI",
174	"DisplayPort",
175	"2-reserved",
176	"3-reserved"
177};
178
179static const char * const cea_audio_coding_type_names[] = {
180	/*  0 */ "undefined",
181	/*  1 */ "LPCM",
182	/*  2 */ "AC-3",
183	/*  3 */ "MPEG1",
184	/*  4 */ "MP3",
185	/*  5 */ "MPEG2",
186	/*  6 */ "AAC-LC",
187	/*  7 */ "DTS",
188	/*  8 */ "ATRAC",
189	/*  9 */ "DSD (One Bit Audio)",
190	/* 10 */ "E-AC-3/DD+ (Dolby Digital Plus)",
191	/* 11 */ "DTS-HD",
192	/* 12 */ "MLP (Dolby TrueHD)",
193	/* 13 */ "DST",
194	/* 14 */ "WMAPro",
195	/* 15 */ "HE-AAC",
196	/* 16 */ "HE-AACv2",
197	/* 17 */ "MPEG Surround",
198};
199
200static const char * const cea_speaker_allocation_names[] = {
201	/*  0 */ "FL/FR",
202	/*  1 */ "LFE",
203	/*  2 */ "FC",
204	/*  3 */ "RL/RR",
205	/*  4 */ "RC",
206	/*  5 */ "FLC/FRC",
207	/*  6 */ "RLC/RRC",
208	/*  7 */ "FLW/FRW",
209	/*  8 */ "FLH/FRH",
210	/*  9 */ "TC",
211	/* 10 */ "FCH",
212};
213
214/*
215 * SS1:SS0 index => sample size
216 */
217static const int cea_sample_sizes[4] = {
218	0,			/* 0: Refer to Stream Header */
219	ELD_PCM_BITS_16,	/* 1: 16 bits */
220	ELD_PCM_BITS_20,	/* 2: 20 bits */
221	ELD_PCM_BITS_24,	/* 3: 24 bits */
222};
223
224/*
225 * SF2:SF1:SF0 index => sampling frequency
226 */
227static const int cea_sampling_frequencies[8] = {
228	0,			/* 0: Refer to Stream Header */
229	SNDRV_PCM_RATE_32000,	/* 1:  32000Hz */
230	SNDRV_PCM_RATE_44100,	/* 2:  44100Hz */
231	SNDRV_PCM_RATE_48000,	/* 3:  48000Hz */
232	SNDRV_PCM_RATE_88200,	/* 4:  88200Hz */
233	SNDRV_PCM_RATE_96000,	/* 5:  96000Hz */
234	SNDRV_PCM_RATE_176400,	/* 6: 176400Hz */
235	SNDRV_PCM_RATE_192000,	/* 7: 192000Hz */
236};
237
238#define GRAB_BITS(buf, byte, lowbit, bits)		\
239({							\
240	BUILD_BUG_ON(lowbit > 7);			\
241	BUILD_BUG_ON(bits > 8);				\
242	BUILD_BUG_ON(bits <= 0);			\
243							\
244	(buf[byte] >> (lowbit)) & ((1 << (bits)) - 1);	\
245})
246
247static void hdmi_update_short_audio_desc(struct device *dev,
248					 struct snd_cea_sad *a,
249					 const unsigned char *buf)
250{
251	int i;
252	int val;
253
254	val = GRAB_BITS(buf, 1, 0, 7);
255	a->rates = 0;
256	for (i = 0; i < 7; i++)
257		if (val & (1 << i))
258			a->rates |= cea_sampling_frequencies[i + 1];
259
260	a->channels = GRAB_BITS(buf, 0, 0, 3);
261	a->channels++;
262
263	a->sample_bits = 0;
264	a->max_bitrate = 0;
265
266	a->format = GRAB_BITS(buf, 0, 3, 4);
267	switch (a->format) {
268	case AUDIO_CODING_TYPE_REF_STREAM_HEADER:
269		dev_info(dev, "HDMI: audio coding type 0 not expected\n");
270		break;
271
272	case AUDIO_CODING_TYPE_LPCM:
273		val = GRAB_BITS(buf, 2, 0, 3);
274		for (i = 0; i < 3; i++)
275			if (val & (1 << i))
276				a->sample_bits |= cea_sample_sizes[i + 1];
277		break;
278
279	case AUDIO_CODING_TYPE_AC3:
280	case AUDIO_CODING_TYPE_MPEG1:
281	case AUDIO_CODING_TYPE_MP3:
282	case AUDIO_CODING_TYPE_MPEG2:
283	case AUDIO_CODING_TYPE_AACLC:
284	case AUDIO_CODING_TYPE_DTS:
285	case AUDIO_CODING_TYPE_ATRAC:
286		a->max_bitrate = GRAB_BITS(buf, 2, 0, 8);
287		a->max_bitrate *= 8000;
288		break;
289
290	case AUDIO_CODING_TYPE_SACD:
291		break;
292
293	case AUDIO_CODING_TYPE_EAC3:
294		break;
295
296	case AUDIO_CODING_TYPE_DTS_HD:
297		break;
298
299	case AUDIO_CODING_TYPE_MLP:
300		break;
301
302	case AUDIO_CODING_TYPE_DST:
303		break;
304
305	case AUDIO_CODING_TYPE_WMAPRO:
306		a->profile = GRAB_BITS(buf, 2, 0, 3);
307		break;
308
309	case AUDIO_CODING_TYPE_REF_CXT:
310		a->format = GRAB_BITS(buf, 2, 3, 5);
311		if (a->format == AUDIO_CODING_XTYPE_HE_REF_CT ||
312		    a->format >= AUDIO_CODING_XTYPE_FIRST_RESERVED) {
313			dev_info(dev,
314				   "HDMI: audio coding xtype %d not expected\n",
315				   a->format);
316			a->format = 0;
317		} else
318			a->format += AUDIO_CODING_TYPE_HE_AAC -
319				     AUDIO_CODING_XTYPE_HE_AAC;
320		break;
321	}
322}
323
324/*
325 * Be careful, ELD buf could be totally rubbish!
326 */
327int snd_parse_eld(struct device *dev, struct snd_parsed_hdmi_eld *e,
328		  const unsigned char *buf, int size)
329{
330	int mnl;
331	int i;
332
333	memset(e, 0, sizeof(*e));
334	e->eld_ver = GRAB_BITS(buf, 0, 3, 5);
335	if (e->eld_ver != ELD_VER_CEA_861D &&
336	    e->eld_ver != ELD_VER_PARTIAL) {
337		dev_info(dev, "HDMI: Unknown ELD version %d\n", e->eld_ver);
338		goto out_fail;
339	}
340
341	e->baseline_len = GRAB_BITS(buf, 2, 0, 8);
342	mnl		= GRAB_BITS(buf, 4, 0, 5);
343	e->cea_edid_ver	= GRAB_BITS(buf, 4, 5, 3);
344
345	e->support_hdcp	= GRAB_BITS(buf, 5, 0, 1);
346	e->support_ai	= GRAB_BITS(buf, 5, 1, 1);
347	e->conn_type	= GRAB_BITS(buf, 5, 2, 2);
348	e->sad_count	= GRAB_BITS(buf, 5, 4, 4);
349
350	e->aud_synch_delay = GRAB_BITS(buf, 6, 0, 8) * 2;
351	e->spk_alloc	= GRAB_BITS(buf, 7, 0, 7);
352
353	e->port_id	  = get_unaligned_le64(buf + 8);
354
355	/* not specified, but the spec's tendency is little endian */
356	e->manufacture_id = get_unaligned_le16(buf + 16);
357	e->product_id	  = get_unaligned_le16(buf + 18);
358
359	if (mnl > ELD_MAX_MNL) {
360		dev_info(dev, "HDMI: MNL is reserved value %d\n", mnl);
361		goto out_fail;
362	} else if (ELD_FIXED_BYTES + mnl > size) {
363		dev_info(dev, "HDMI: out of range MNL %d\n", mnl);
364		goto out_fail;
365	} else
366		strscpy(e->monitor_name, buf + ELD_FIXED_BYTES, mnl + 1);
367
368	for (i = 0; i < e->sad_count; i++) {
369		if (ELD_FIXED_BYTES + mnl + 3 * (i + 1) > size) {
370			dev_info(dev, "HDMI: out of range SAD %d\n", i);
371			goto out_fail;
372		}
373		hdmi_update_short_audio_desc(dev, e->sad + i,
374					     buf + ELD_FIXED_BYTES + mnl + 3 * i);
375	}
376
377	/*
378	 * HDMI sink's ELD info cannot always be retrieved for now, e.g.
379	 * in console or for audio devices. Assume the highest speakers
380	 * configuration, to _not_ prohibit multi-channel audio playback.
381	 */
382	if (!e->spk_alloc && e->sad_count)
383		e->spk_alloc = 0xffff;
384
385	return 0;
386
387out_fail:
388	return -EINVAL;
389}
390EXPORT_SYMBOL_GPL(snd_parse_eld);
391
392/*
393 * SNDRV_PCM_RATE_* and AC_PAR_PCM values don't match, print correct rates with
394 * hdmi-specific routine.
395 */
396static void hdmi_print_pcm_rates(int pcm, char *buf, int buflen)
397{
398	static const unsigned int alsa_rates[] = {
399		5512, 8000, 11025, 16000, 22050, 32000, 44100, 48000, 64000,
400		88200, 96000, 176400, 192000, 384000
401	};
402	int i, j;
403
404	for (i = 0, j = 0; i < ARRAY_SIZE(alsa_rates); i++)
405		if (pcm & (1 << i))
406			j += scnprintf(buf + j, buflen - j,  " %d",
407				alsa_rates[i]);
408
409	buf[j] = '\0'; /* necessary when j == 0 */
410}
411
412static void eld_print_pcm_bits(int pcm, char *buf, int buflen)
413{
414	static const unsigned int bits[] = { 8, 16, 20, 24, 32 };
415	int i, j;
416
417	for (i = 0, j = 0; i < ARRAY_SIZE(bits); i++)
418		if (pcm & (ELD_PCM_BITS_8 << i))
419			j += scnprintf(buf + j, buflen - j,  " %d", bits[i]);
420
421	buf[j] = '\0'; /* necessary when j == 0 */
422}
423
424static void hdmi_show_short_audio_desc(struct device *dev,
425				       struct snd_cea_sad *a)
426{
427	char buf[SND_PRINT_RATES_ADVISED_BUFSIZE];
428	char buf2[8 + SND_PRINT_BITS_ADVISED_BUFSIZE] = ", bits =";
429
430	if (!a->format)
431		return;
432
433	hdmi_print_pcm_rates(a->rates, buf, sizeof(buf));
434
435	if (a->format == AUDIO_CODING_TYPE_LPCM)
436		eld_print_pcm_bits(a->sample_bits, buf2 + 8, sizeof(buf2) - 8);
437	else if (a->max_bitrate)
438		snprintf(buf2, sizeof(buf2),
439				", max bitrate = %d", a->max_bitrate);
440	else
441		buf2[0] = '\0';
442
443	dev_dbg(dev,
444		"HDMI: supports coding type %s: channels = %d, rates =%s%s\n",
445		cea_audio_coding_type_names[a->format],
446		a->channels, buf, buf2);
447}
448
449static void snd_eld_print_channel_allocation(int spk_alloc, char *buf, int buflen)
450{
451	int i, j;
452
453	for (i = 0, j = 0; i < ARRAY_SIZE(cea_speaker_allocation_names); i++) {
454		if (spk_alloc & (1 << i))
455			j += scnprintf(buf + j, buflen - j,  " %s",
456					cea_speaker_allocation_names[i]);
457	}
458	buf[j] = '\0';	/* necessary when j == 0 */
459}
460
461void snd_show_eld(struct device *dev, struct snd_parsed_hdmi_eld *e)
462{
463	int i;
464
465	dev_dbg(dev, "HDMI: detected monitor %s at connection type %s\n",
466		e->monitor_name,
467		eld_connection_type_names[e->conn_type]);
468
469	if (e->spk_alloc) {
470		char buf[SND_PRINT_CHANNEL_ALLOCATION_ADVISED_BUFSIZE];
471
472		snd_eld_print_channel_allocation(e->spk_alloc, buf, sizeof(buf));
473		dev_dbg(dev, "HDMI: available speakers:%s\n", buf);
474	}
475
476	for (i = 0; i < e->sad_count; i++)
477		hdmi_show_short_audio_desc(dev, e->sad + i);
478}
479EXPORT_SYMBOL_GPL(snd_show_eld);
480
481#ifdef CONFIG_SND_PROC_FS
482static void hdmi_print_sad_info(int i, struct snd_cea_sad *a,
483				struct snd_info_buffer *buffer)
484{
485	char buf[SND_PRINT_RATES_ADVISED_BUFSIZE];
486
487	snd_iprintf(buffer, "sad%d_coding_type\t[0x%x] %s\n",
488			i, a->format, cea_audio_coding_type_names[a->format]);
489	snd_iprintf(buffer, "sad%d_channels\t\t%d\n", i, a->channels);
490
491	hdmi_print_pcm_rates(a->rates, buf, sizeof(buf));
492	snd_iprintf(buffer, "sad%d_rates\t\t[0x%x]%s\n", i, a->rates, buf);
493
494	if (a->format == AUDIO_CODING_TYPE_LPCM) {
495		eld_print_pcm_bits(a->sample_bits, buf, sizeof(buf));
496		snd_iprintf(buffer, "sad%d_bits\t\t[0x%x]%s\n",
497							i, a->sample_bits, buf);
498	}
499
500	if (a->max_bitrate)
501		snd_iprintf(buffer, "sad%d_max_bitrate\t%d\n",
502							i, a->max_bitrate);
503
504	if (a->profile)
505		snd_iprintf(buffer, "sad%d_profile\t\t%d\n", i, a->profile);
506}
507
508void snd_print_eld_info(struct snd_parsed_hdmi_eld *e,
509			struct snd_info_buffer *buffer)
510{
511	char buf[SND_PRINT_CHANNEL_ALLOCATION_ADVISED_BUFSIZE];
512	int i;
513	static const char * const eld_version_names[32] = {
514		"reserved",
515		"reserved",
516		"CEA-861D or below",
517		[3 ... 30] = "reserved",
518		[31] = "partial"
519	};
520	static const char * const cea_edid_version_names[8] = {
521		"no CEA EDID Timing Extension block present",
522		"CEA-861",
523		"CEA-861-A",
524		"CEA-861-B, C or D",
525		[4 ... 7] = "reserved"
526	};
527
528	snd_iprintf(buffer, "monitor_name\t\t%s\n", e->monitor_name);
529	snd_iprintf(buffer, "connection_type\t\t%s\n",
530				eld_connection_type_names[e->conn_type]);
531	snd_iprintf(buffer, "eld_version\t\t[0x%x] %s\n", e->eld_ver,
532					eld_version_names[e->eld_ver]);
533	snd_iprintf(buffer, "edid_version\t\t[0x%x] %s\n", e->cea_edid_ver,
534				cea_edid_version_names[e->cea_edid_ver]);
535	snd_iprintf(buffer, "manufacture_id\t\t0x%x\n", e->manufacture_id);
536	snd_iprintf(buffer, "product_id\t\t0x%x\n", e->product_id);
537	snd_iprintf(buffer, "port_id\t\t\t0x%llx\n", (long long)e->port_id);
538	snd_iprintf(buffer, "support_hdcp\t\t%d\n", e->support_hdcp);
539	snd_iprintf(buffer, "support_ai\t\t%d\n", e->support_ai);
540	snd_iprintf(buffer, "audio_sync_delay\t%d\n", e->aud_synch_delay);
541
542	snd_eld_print_channel_allocation(e->spk_alloc, buf, sizeof(buf));
543	snd_iprintf(buffer, "speakers\t\t[0x%x]%s\n", e->spk_alloc, buf);
544
545	snd_iprintf(buffer, "sad_count\t\t%d\n", e->sad_count);
546
547	for (i = 0; i < e->sad_count; i++)
548		hdmi_print_sad_info(i, e->sad + i, buffer);
549}
550EXPORT_SYMBOL_GPL(snd_print_eld_info);
551#endif /* CONFIG_SND_PROC_FS */