Allwinner: WIP audio passthrough

packages/audio/alsa-lib/patches/alsa-lib-001-iec958-hbr.patch

@@ -0,0 +1,150 @@
+From 04226851079cf2a76937583f7debbdcda56d6f08 Mon Sep 17 00:00:00 2001
+From: Matthias Reichl <hias@horus.com>
+Date: Tue, 30 Jun 2020 12:45:54 +0200
+Subject: [PATCH] pcm_iec958: implement HDMI HBR audio compliant formatting
+
+HBR compressed audio data like DTS HD MA is usually packed into
+8-channel PCM frames (typically 192kHz). The HDMI specs state this has
+to be formatted as a single IEC958 stream, compared to normal multi-
+channel PCM data which has to be formatted as parallel IEC958 streams.
+
+As this single-stream formatting mode may break existing setups that
+expect non-PCM multichannel data to be formatted as parallel IEC958
+streams it needs to be explicitly selected by setting the hbr_mode
+option to true.
+
+If hbr_mode is true and the non-audio channel status bit is set then
+the data is formatted accordingly, as contiguous IEC958 frames of
+a single IEC958 stream.
+
+Signed-off-by: Matthias Reichl <hias@horus.com>
+---
+ src/pcm/pcm_iec958.c | 37 +++++++++++++++++++++++++++++++++----
+ 1 file changed, 33 insertions(+), 4 deletions(-)
+
+diff --git a/src/pcm/pcm_iec958.c b/src/pcm/pcm_iec958.c
+index 76d3ca7b..dba41e1e 100644
+--- a/src/pcm/pcm_iec958.c
++++ b/src/pcm/pcm_iec958.c
+@@ -63,6 +63,7 @@ struct snd_pcm_iec958 {
+ 	unsigned int byteswap;
+ 	unsigned char preamble[3];	/* B/M/W or Z/X/Y */
+ 	snd_pcm_fast_ops_t fops;
++	int hbr_mode;
+ };
+
+ enum { PREAMBLE_Z, PREAMBLE_X, PREAMBLE_Y };
+@@ -193,6 +194,8 @@ static void snd_pcm_iec958_encode(snd_pcm_iec958_t *iec,
+ 	unsigned int channel;
+ 	int32_t sample = 0;
+ 	int counter = iec->counter;
++	int single_stream = iec->hbr_mode && (iec->status[0] & IEC958_AES0_NONAUDIO);
++	int counter_step = single_stream ? ((channels + 1) >> 1) : 1;
+ 	for (channel = 0; channel < channels; ++channel) {
+ 		const char *src;
+ 		uint32_t *dst;
+@@ -205,7 +208,12 @@ static void snd_pcm_iec958_encode(snd_pcm_iec958_t *iec,
+ 		src_step = snd_pcm_channel_area_step(src_area);
+ 		dst_step = snd_pcm_channel_area_step(dst_area) / sizeof(uint32_t);
+ 		frames1 = frames;
+-		iec->counter = counter;
++
++		if (single_stream)
++			iec->counter = (counter + (channel >> 1)) % 192;
++		else
++			iec->counter = counter;
++
+ 		while (frames1-- > 0) {
+ 			goto *get;
+ #define GET32_END after
+@@ -217,9 +225,12 @@ static void snd_pcm_iec958_encode(snd_pcm_iec958_t *iec,
+ 			*dst = sample;
+ 			src += src_step;
+ 			dst += dst_step;
+-			iec->counter++;
++			iec->counter += counter_step;
+ 			iec->counter %= 192;
+ 		}
++		if (single_stream) {
++			iec->counter = (counter + frames * counter_step) % 192;
++		}
+ 	}
+ }
+ #endif /* DOC_HIDDEN */
+@@ -473,6 +484,7 @@ static const snd_pcm_ops_t snd_pcm_iec958_ops = {
+  * \param close_slave When set, the slave PCM handle is closed with copy PCM
+  * \param status_bits The IEC958 status bits
+  * \param preamble_vals The preamble byte values
++ * \param hbr_mode When set, enable HDMI HBR compliant formatting
+  * \retval zero on success otherwise a negative error code
+  * \warning Using of this function might be dangerous in the sense
+  *          of compatibility reasons. The prototype might be freely
+@@ -481,7 +493,8 @@ static const snd_pcm_ops_t snd_pcm_iec958_ops = {
+ int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sformat,
+ 			snd_pcm_t *slave, int close_slave,
+ 			const unsigned char *status_bits,
+-			const unsigned char *preamble_vals)
++			const unsigned char *preamble_vals,
++		        int hbr_mode)
+ {
+ 	snd_pcm_t *pcm;
+ 	snd_pcm_iec958_t *iec;
+@@ -519,6 +532,8 @@ int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sfo
+
+ 	memcpy(iec->preamble, preamble_vals, 3);
+
++	iec->hbr_mode = hbr_mode;
++
+ 	err = snd_pcm_new(&pcm, SND_PCM_TYPE_IEC958, name, slave->stream, slave->mode);
+ 	if (err < 0) {
+ 		free(iec);
+@@ -566,9 +581,15 @@ pcm.name {
+ 	[preamble.z or preamble.b val]
+ 	[preamble.x or preamble.m val]
+ 	[preamble.y or preamble.w val]
++	[hbr_mode true]
+ }
+ \endcode
+
++When <code>hbr_mode</code> is set true, multichannel compressed
++data is formatted as contiguous frames of a single IEC958 stream.
++Eg 8-channel PCM as typically used for HDMI HBR audio is formatted
++as 4 contiguous iec958 frames.
++
+ \subsection pcm_plugins_iec958_funcref Function reference
+
+ <UL>
+@@ -605,6 +626,7 @@ int _snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name,
+ 	unsigned char preamble_vals[3] = {
+ 		0x08, 0x02, 0x04 /* Z, X, Y */
+ 	};
++	int hbr_mode = 0;
+
+ 	snd_config_for_each(i, next, conf) {
+ 		snd_config_t *n = snd_config_iterator_entry(i);
+@@ -633,6 +655,13 @@ int _snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name,
+ 			preamble = n;
+ 			continue;
+ 		}
++		if (strcmp(id, "hbr_mode") == 0) {
++			err = snd_config_get_bool(n);
++			if (err < 0)
++				continue;
++			hbr_mode = err;
++			continue;
++		}
+ 		SNDERR("Unknown field %s", id);
+ 		return -EINVAL;
+ 	}
+@@ -707,7 +736,7 @@ int _snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name,
+ 		return err;
+ 	err = snd_pcm_iec958_open(pcmp, name, sformat, spcm, 1,
+ 				  status ? status_bits : NULL,
+-				  preamble_vals);
++				  preamble_vals, hbr_mode);
+ 	if (err < 0)
+ 		snd_pcm_close(spcm);
+ 	return err;
+-- 
+2.20.1
+

packages/audio/alsa-lib/patches/alsa-lib-002-iec958-format.patch

@@ -0,0 +1,112 @@
+From dec023cd0d5fb6e2adb36de3f3ae2d4a4677950f Mon Sep 17 00:00:00 2001
+From: Matthias Reichl <hias@horus.com>
+Date: Tue, 30 Jun 2020 17:34:52 +0200
+Subject: [PATCH] pcm_iec958: set status bits according to rate and format
+
+This mimics snd_pcm_create_iec958_consumer in the kernel.
+
+The rate and wordlength bits will only be changed if they were
+previously set to "not indicated", which is now the default if no
+status option is used.
+
+This allows application to override the parameters determined from
+the stream which is eg needed for HDMI HBR passthrough (8ch 192kHz
+data but status bits need to be set to 768kHz).
+
+Signed-off-by: Matthias Reichl <hias@horus.com>
+---
+ src/pcm/pcm_iec958.c | 71 +++++++++++++++++++++++++++++++++++++++++---
+ 1 file changed, 67 insertions(+), 4 deletions(-)
+
+diff --git a/src/pcm/pcm_iec958.c b/src/pcm/pcm_iec958.c
+index dba41e1e..dd64aac6 100644
+--- a/src/pcm/pcm_iec958.c
++++ b/src/pcm/pcm_iec958.c
+@@ -364,9 +364,71 @@ static int snd_pcm_iec958_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t * params
+ 			iec->byteswap = format != SND_PCM_FORMAT_IEC958_SUBFRAME;
+ 		}
+ 	}
+-	/* FIXME: needs to adjust status_bits according to the format
+-	 *        and sample rate
+-	 */
++
++	if ((iec->status[0] & IEC958_AES0_PROFESSIONAL) == 0) {
++		if ((iec->status[3] & IEC958_AES3_CON_FS) == IEC958_AES3_CON_FS_NOTID) {
++			unsigned int rate = 0;
++			unsigned char fs;
++
++			err = INTERNAL(snd_pcm_hw_params_get_rate)(params, &rate, 0);
++			if (err < 0)
++				rate = 0;
++
++			switch (rate) {
++			case 32000:
++				fs = IEC958_AES3_CON_FS_32000;
++				break;
++			case 44100:
++				fs = IEC958_AES3_CON_FS_44100;
++				break;
++			case 48000:
++				fs = IEC958_AES3_CON_FS_48000;
++				break;
++			case 88200:
++				fs = IEC958_AES3_CON_FS_88200;
++				break;
++			case 96000:
++				fs = IEC958_AES3_CON_FS_96000;
++				break;
++			case 176400:
++				fs = IEC958_AES3_CON_FS_176400;
++				break;
++			case 192000:
++				fs = IEC958_AES3_CON_FS_192000;
++				break;
++			default:
++				fs = IEC958_AES3_CON_FS_NOTID;
++				break;
++			}
++
++			iec->status[3] &= ~IEC958_AES3_CON_FS;
++			iec->status[3] |= fs;
++		}
++
++		if ((iec->status[4] & IEC958_AES4_CON_WORDLEN) == IEC958_AES4_CON_WORDLEN_NOTID) {
++			unsigned char ws;
++			switch (snd_pcm_format_width(format)) {
++			case 16:
++				ws = IEC958_AES4_CON_WORDLEN_20_16;
++				break;
++			case 18:
++				ws = IEC958_AES4_CON_WORDLEN_22_18;
++				break;
++			case 20:
++				ws = IEC958_AES4_CON_WORDLEN_20_16 | IEC958_AES4_CON_MAX_WORDLEN_24;
++				break;
++			case 24:
++			case 32: /* Assume 24-bit width for 32-bit samples. */
++				ws = IEC958_AES4_CON_WORDLEN_24_20 | IEC958_AES4_CON_MAX_WORDLEN_24;
++				break;
++			default:
++				ws = IEC958_AES4_CON_WORDLEN_NOTID;
++				break;
++			}
++			iec->status[4] &= ~(IEC958_AES4_CON_MAX_WORDLEN_24 | IEC958_AES4_CON_WORDLEN);
++			iec->status[4] |= ws;
++		}
++	}
+ 	return 0;
+ }
+
+@@ -503,7 +565,8 @@ int snd_pcm_iec958_open(snd_pcm_t **pcmp, const char *name, snd_pcm_format_t sfo
+ 		IEC958_AES0_CON_EMPHASIS_NONE,
+ 		IEC958_AES1_CON_ORIGINAL | IEC958_AES1_CON_PCM_CODER,
+ 		0,
+-		IEC958_AES3_CON_FS_48000
++		IEC958_AES3_CON_FS_NOTID, /* will be set in hwparams */
++		IEC958_AES4_CON_WORDLEN_NOTID /* will be set in hwparams */
+ 	};
+
+ 	assert(pcmp && slave);
+-- 
+2.20.1
+

packages/audio/alsa-lib/patches/test.patch

@@ -0,0 +1,105 @@
+diff --git a/src/pcm/pcm_hw.c b/src/pcm/pcm_hw.c
+index 2028790eba78..115db2c2cdae 100644
+--- a/src/pcm/pcm_hw.c
++++ b/src/pcm/pcm_hw.c
+@@ -41,8 +41,8 @@
+ #include "../control/control_local.h"
+ #include "../timer/timer_local.h"
+
+-//#define DEBUG_RW		/* use to debug readi/writei/readn/writen */
+-//#define DEBUG_MMAP		/* debug mmap_commit */
++#define DEBUG_RW		/* use to debug readi/writei/readn/writen */
++#define DEBUG_MMAP		/* debug mmap_commit */
+
+ #ifndef PIC
+ /* entry for static linking */
+diff --git a/src/pcm/pcm_iec958.c b/src/pcm/pcm_iec958.c
+index dd64aac65d8f..087393b29681 100644
+--- a/src/pcm/pcm_iec958.c
++++ b/src/pcm/pcm_iec958.c
+@@ -71,8 +71,8 @@ enum { PREAMBLE_Z, PREAMBLE_X, PREAMBLE_Y };
+ #endif /* DOC_HIDDEN */
+
+ /*
+- * Determine parity for time slots 4 upto 30
+- * to be sure that bit 4 upt 31 will carry
++ * Determine parity for time slots 0 upto 18
++ * to be sure that bit 0 upt 19 will carry
+  * an even number of ones and zeros.
+  */
+ static unsigned int iec958_parity(unsigned int data)
+@@ -80,9 +80,8 @@ static unsigned int iec958_parity(unsigned int data)
+ 	unsigned int parity;
+ 	int bit;
+
+-	data >>= 4;     /* start from bit 4 */
+ 	parity = 0;
+-	for (bit = 4; bit <= 30; bit++) {
++	for (bit = 0; bit <= 18; bit++) {
+ 		if (data & 1)
+ 			parity++;
+ 		data >>= 1;
+@@ -94,13 +93,12 @@ static unsigned int iec958_parity(unsigned int data)
+  * Compose 32bit IEC958 subframe, two sub frames
+  * build one frame with two channels.
+  *
+- * bit 0-3  = preamble
+- *     4-7  = AUX (=0)
+- *     8-27 = data (12-27 for 16bit, 8-27 for 20bit, and 24bit without AUX)
+- *     28   = validity (0 for valid data, else 'in error')
+- *     29   = user data (0)
+- *     30   = channel status (24 bytes for 192 frames)
+- *     31   = parity
++ * bit 0-15 = data
++ *     16   = validity (0 for valid data, else 'in error')
++ *     17   = user data (0)
++ *     18   = channel status (24 bytes for 192 frames)
++ *     19   = parity
++ *     20   = frame start
+  */
+
+ static inline uint32_t iec958_subframe(snd_pcm_iec958_t *iec, uint32_t data, int channel)
+@@ -108,24 +106,20 @@ static inline uint32_t iec958_subframe(snd_pcm_iec958_t *iec, uint32_t data, int
+ 	unsigned int byte = iec->counter >> 3;
+ 	unsigned int mask = 1 << (iec->counter - (byte << 3));
+
+-	/* bit 4-27 */
+-	data >>= 4;
+-	data &= ~0xf;
++	data >>= 16;
+
+ 	/* set IEC status bits (up to 192 bits) */
+ 	if (iec->status[byte] & mask)
+-		data |= 0x40000000;
++		data |= 0x40000;
+
+-	if (iec958_parity(data))	/* parity bit 4-30 */
+-		data |= 0x80000000;
++	if (iec958_parity(data))
++		data |= 0x80000;
+
+-	/* Preamble */
+-	if (channel)
+-		data |= iec->preamble[PREAMBLE_Y];	/* odd sub frame, 'Y' */
+-	else if (! iec->counter)
+-		data |= iec->preamble[PREAMBLE_Z];	/* Block start, 'Z' */
+-	else
+-		data |= iec->preamble[PREAMBLE_X];	/* even sub frame, 'X' */
++	/* block start */
++	if (!iec->counter)
++		data |= 0x100000;
++
++	data <<= 11;
+
+ 	if (iec->byteswap)
+ 		data = bswap_32(data);
+@@ -137,8 +131,7 @@ static inline int32_t iec958_to_s32(snd_pcm_iec958_t *iec, uint32_t data)
+ {
+ 	if (iec->byteswap)
+ 		data = bswap_32(data);
+-	data &= ~0xf;
+-	data <<= 4;
++	data <<= 16;
+ 	return (int32_t)data;
+ }
+