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v5.4
 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 *  PCM DRM helpers
 4 */
 
 5#include <linux/export.h>
 
 6#include <drm/drm_edid.h>
 
 7#include <sound/pcm.h>
 8#include <sound/pcm_drm_eld.h>
 9
 
 
 
 
 
 
 
 
 
 
 
 
10static const unsigned int eld_rates[] = {
11	32000,
12	44100,
13	48000,
14	88200,
15	96000,
16	176400,
17	192000,
18};
19
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
20static unsigned int sad_max_channels(const u8 *sad)
21{
22	return 1 + (sad[0] & 7);
 
 
 
 
 
 
 
 
 
 
 
 
 
23}
24
25static int eld_limit_rates(struct snd_pcm_hw_params *params,
26			   struct snd_pcm_hw_rule *rule)
27{
28	struct snd_interval *r = hw_param_interval(params, rule->var);
29	const struct snd_interval *c;
30	unsigned int rate_mask = 7, i;
31	const u8 *sad, *eld = rule->private;
32
33	sad = drm_eld_sad(eld);
34	if (sad) {
35		c = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
36
37		for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3) {
38			unsigned max_channels = sad_max_channels(sad);
39
40			/*
41			 * Exclude SADs which do not include the
42			 * requested number of channels.
43			 */
44			if (c->min <= max_channels)
45				rate_mask |= sad[1];
46		}
47	}
48
49	return snd_interval_list(r, ARRAY_SIZE(eld_rates), eld_rates,
50				 rate_mask);
51}
52
53static int eld_limit_channels(struct snd_pcm_hw_params *params,
54			      struct snd_pcm_hw_rule *rule)
55{
56	struct snd_interval *c = hw_param_interval(params, rule->var);
57	const struct snd_interval *r;
58	struct snd_interval t = { .min = 1, .max = 2, .integer = 1, };
59	unsigned int i;
60	const u8 *sad, *eld = rule->private;
61
62	sad = drm_eld_sad(eld);
63	if (sad) {
64		unsigned int rate_mask = 0;
65
66		/* Convert the rate interval to a mask */
67		r = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
68		for (i = 0; i < ARRAY_SIZE(eld_rates); i++)
69			if (r->min <= eld_rates[i] && r->max >= eld_rates[i])
70				rate_mask |= BIT(i);
71
72		for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3)
73			if (rate_mask & sad[1])
74				t.max = max(t.max, sad_max_channels(sad));
75	}
76
77	return snd_interval_refine(c, &t);
78}
79
80int snd_pcm_hw_constraint_eld(struct snd_pcm_runtime *runtime, void *eld)
81{
82	int ret;
83
84	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
85				  eld_limit_rates, eld,
86				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
87	if (ret < 0)
88		return ret;
89
90	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
91				  eld_limit_channels, eld,
92				  SNDRV_PCM_HW_PARAM_RATE, -1);
93
94	return ret;
95}
96EXPORT_SYMBOL_GPL(snd_pcm_hw_constraint_eld);
v6.8
  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 <drm/drm_edid.h>
  9#include <drm/drm_eld.h>
 10#include <sound/pcm.h>
 11#include <sound/pcm_drm_eld.h>
 12
 13#define SAD0_CHANNELS_MASK	GENMASK(2, 0) /* max number of channels - 1 */
 14#define SAD0_FORMAT_MASK	GENMASK(6, 3) /* audio format */
 15
 16#define SAD1_RATE_MASK		GENMASK(6, 0) /* bitfield of supported rates */
 17#define SAD1_RATE_32000_MASK	BIT(0)
 18#define SAD1_RATE_44100_MASK	BIT(1)
 19#define SAD1_RATE_48000_MASK	BIT(2)
 20#define SAD1_RATE_88200_MASK	BIT(3)
 21#define SAD1_RATE_96000_MASK	BIT(4)
 22#define SAD1_RATE_176400_MASK	BIT(5)
 23#define SAD1_RATE_192000_MASK	BIT(6)
 24
 25static const unsigned int eld_rates[] = {
 26	32000,
 27	44100,
 28	48000,
 29	88200,
 30	96000,
 31	176400,
 32	192000,
 33};
 34
 35static unsigned int map_rate_families(const u8 *sad,
 36				      unsigned int mask_32000,
 37				      unsigned int mask_44100,
 38				      unsigned int mask_48000)
 39{
 40	unsigned int rate_mask = 0;
 41
 42	if (sad[1] & SAD1_RATE_32000_MASK)
 43		rate_mask |= mask_32000;
 44	if (sad[1] & (SAD1_RATE_44100_MASK | SAD1_RATE_88200_MASK | SAD1_RATE_176400_MASK))
 45		rate_mask |= mask_44100;
 46	if (sad[1] & (SAD1_RATE_48000_MASK | SAD1_RATE_96000_MASK | SAD1_RATE_192000_MASK))
 47		rate_mask |= mask_48000;
 48	return rate_mask;
 49}
 50
 51static unsigned int sad_rate_mask(const u8 *sad)
 52{
 53	switch (FIELD_GET(SAD0_FORMAT_MASK, sad[0])) {
 54	case HDMI_AUDIO_CODING_TYPE_PCM:
 55		return sad[1] & SAD1_RATE_MASK;
 56	case HDMI_AUDIO_CODING_TYPE_AC3:
 57	case HDMI_AUDIO_CODING_TYPE_DTS:
 58		return map_rate_families(sad,
 59					 SAD1_RATE_32000_MASK,
 60					 SAD1_RATE_44100_MASK,
 61					 SAD1_RATE_48000_MASK);
 62	case HDMI_AUDIO_CODING_TYPE_EAC3:
 63	case HDMI_AUDIO_CODING_TYPE_DTS_HD:
 64	case HDMI_AUDIO_CODING_TYPE_MLP:
 65		return map_rate_families(sad,
 66					 0,
 67					 SAD1_RATE_176400_MASK,
 68					 SAD1_RATE_192000_MASK);
 69	default:
 70		/* TODO adjust for other compressed formats as well */
 71		return sad[1] & SAD1_RATE_MASK;
 72	}
 73}
 74
 75static unsigned int sad_max_channels(const u8 *sad)
 76{
 77	switch (FIELD_GET(SAD0_FORMAT_MASK, sad[0])) {
 78	case HDMI_AUDIO_CODING_TYPE_PCM:
 79		return 1 + FIELD_GET(SAD0_CHANNELS_MASK, sad[0]);
 80	case HDMI_AUDIO_CODING_TYPE_AC3:
 81	case HDMI_AUDIO_CODING_TYPE_DTS:
 82	case HDMI_AUDIO_CODING_TYPE_EAC3:
 83		return 2;
 84	case HDMI_AUDIO_CODING_TYPE_DTS_HD:
 85	case HDMI_AUDIO_CODING_TYPE_MLP:
 86		return 8;
 87	default:
 88		/* TODO adjust for other compressed formats as well */
 89		return 1 + FIELD_GET(SAD0_CHANNELS_MASK, sad[0]);
 90	}
 91}
 92
 93static int eld_limit_rates(struct snd_pcm_hw_params *params,
 94			   struct snd_pcm_hw_rule *rule)
 95{
 96	struct snd_interval *r = hw_param_interval(params, rule->var);
 97	const struct snd_interval *c;
 98	unsigned int rate_mask = 7, i;
 99	const u8 *sad, *eld = rule->private;
100
101	sad = drm_eld_sad(eld);
102	if (sad) {
103		c = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_CHANNELS);
104
105		for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3) {
106			unsigned max_channels = sad_max_channels(sad);
107
108			/*
109			 * Exclude SADs which do not include the
110			 * requested number of channels.
111			 */
112			if (c->min <= max_channels)
113				rate_mask |= sad_rate_mask(sad);
114		}
115	}
116
117	return snd_interval_list(r, ARRAY_SIZE(eld_rates), eld_rates,
118				 rate_mask);
119}
120
121static int eld_limit_channels(struct snd_pcm_hw_params *params,
122			      struct snd_pcm_hw_rule *rule)
123{
124	struct snd_interval *c = hw_param_interval(params, rule->var);
125	const struct snd_interval *r;
126	struct snd_interval t = { .min = 1, .max = 2, .integer = 1, };
127	unsigned int i;
128	const u8 *sad, *eld = rule->private;
129
130	sad = drm_eld_sad(eld);
131	if (sad) {
132		unsigned int rate_mask = 0;
133
134		/* Convert the rate interval to a mask */
135		r = hw_param_interval_c(params, SNDRV_PCM_HW_PARAM_RATE);
136		for (i = 0; i < ARRAY_SIZE(eld_rates); i++)
137			if (r->min <= eld_rates[i] && r->max >= eld_rates[i])
138				rate_mask |= BIT(i);
139
140		for (i = drm_eld_sad_count(eld); i > 0; i--, sad += 3)
141			if (rate_mask & sad_rate_mask(sad))
142				t.max = max(t.max, sad_max_channels(sad));
143	}
144
145	return snd_interval_refine(c, &t);
146}
147
148int snd_pcm_hw_constraint_eld(struct snd_pcm_runtime *runtime, void *eld)
149{
150	int ret;
151
152	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
153				  eld_limit_rates, eld,
154				  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
155	if (ret < 0)
156		return ret;
157
158	ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
159				  eld_limit_channels, eld,
160				  SNDRV_PCM_HW_PARAM_RATE, -1);
161
162	return ret;
163}
164EXPORT_SYMBOL_GPL(snd_pcm_hw_constraint_eld);