[linux-2.6-block.git] / sound / firewire / digi00x / amdtp-dot.c

/*
 * amdtp-dot.c - a part of driver for Digidesign Digi 002/003 family
 *
 * Copyright (c) 2014-2015 Takashi Sakamoto
 * Copyright (C) 2012 Robin Gareus <robin@gareus.org>
 * Copyright (C) 2012 Damien Zammit <damien@zamaudio.com>
 *
 * Licensed under the terms of the GNU General Public License, version 2.
 */

#include <sound/pcm.h>
#include "digi00x.h"

#define CIP_FMT_AM		0x10

/* 'Clock-based rate control mode' is just supported. */
#define AMDTP_FDF_AM824		0x00

/*
 * Nominally 3125 bytes/second, but the MIDI port's clock might be
 * 1% too slow, and the bus clock 100 ppm too fast.
 */
#define MIDI_BYTES_PER_SECOND	3093

/*
 * Several devices look only at the first eight data blocks.
 * In any case, this is more than enough for the MIDI data rate.
 */
#define MAX_MIDI_RX_BLOCKS	8

/* 3 = MAX(DOT_MIDI_IN_PORTS, DOT_MIDI_OUT_PORTS) + 1. */
#define MAX_MIDI_PORTS		3

/*
 * The double-oh-three algorithm was discovered by Robin Gareus and Damien
 * Zammit in 2012, with reverse-engineering for Digi 003 Rack.
 */
struct dot_state {
	u8 carry;
	u8 idx;
	unsigned int off;
};

struct amdtp_dot {
	unsigned int pcm_channels;
	struct dot_state state;

	struct snd_rawmidi_substream *midi[MAX_MIDI_PORTS];
	int midi_fifo_used[MAX_MIDI_PORTS];
	int midi_fifo_limit;
};

/*
 * double-oh-three look up table
 *
 * @param idx index byte (audio-sample data) 0x00..0xff
 * @param off channel offset shift
 * @return salt to XOR with given data
 */
#define BYTE_PER_SAMPLE (4)
#define MAGIC_DOT_BYTE (2)
#define MAGIC_BYTE_OFF(x) (((x) * BYTE_PER_SAMPLE) + MAGIC_DOT_BYTE)
static u8 dot_scrt(const u8 idx, const unsigned int off)
{
	/*
	 * the length of the added pattern only depends on the lower nibble
	 * of the last non-zero data
	 */
	static const u8 len[16] = {0, 1, 3, 5, 7, 9, 11, 13, 14,
				   12, 10, 8, 6, 4, 2, 0};

	/*
	 * the lower nibble of the salt. Interleaved sequence.
	 * this is walked backwards according to len[]
	 */
	static const u8 nib[15] = {0x8, 0x7, 0x9, 0x6, 0xa, 0x5, 0xb, 0x4,
				   0xc, 0x3, 0xd, 0x2, 0xe, 0x1, 0xf};

	/* circular list for the salt's hi nibble. */
	static const u8 hir[15] = {0x0, 0x6, 0xf, 0x8, 0x7, 0x5, 0x3, 0x4,
				   0xc, 0xd, 0xe, 0x1, 0x2, 0xb, 0xa};

	/*
	 * start offset for upper nibble mapping.
	 * note: 9 is /special/. In the case where the high nibble == 0x9,
	 * hir[] is not used and - coincidentally - the salt's hi nibble is
	 * 0x09 regardless of the offset.
	 */
	static const u8 hio[16] = {0, 11, 12, 6, 7, 5, 1, 4,
				   3, 0x00, 14, 13, 8, 9, 10, 2};

	const u8 ln = idx & 0xf;
	const u8 hn = (idx >> 4) & 0xf;
	const u8 hr = (hn == 0x9) ? 0x9 : hir[(hio[hn] + off) % 15];

	if (len[ln] < off)
		return 0x00;

	return ((nib[14 + off - len[ln]]) | (hr << 4));
}

static void dot_encode_step(struct dot_state *state, __be32 *const buffer)
{
	u8 * const data = (u8 *) buffer;

	if (data[MAGIC_DOT_BYTE] != 0x00) {
		state->off = 0;
		state->idx = data[MAGIC_DOT_BYTE] ^ state->carry;
	}
	data[MAGIC_DOT_BYTE] ^= state->carry;
	state->carry = dot_scrt(state->idx, ++(state->off));
}

int amdtp_dot_set_parameters(struct amdtp_stream *s, unsigned int rate,
			     unsigned int pcm_channels)
{
	struct amdtp_dot *p = s->protocol;
	int err;

	if (amdtp_stream_running(s))
		return -EBUSY;

	/*
	 * A first data channel is for MIDI messages, the rest is Multi Bit
	 * Linear Audio data channel.
	 */
	err = amdtp_stream_set_parameters(s, rate, pcm_channels + 1);
	if (err < 0)
		return err;

	s->fdf = AMDTP_FDF_AM824 | s->sfc;

	p->pcm_channels = pcm_channels;

	/*
	 * We do not know the actual MIDI FIFO size of most devices.  Just
	 * assume two bytes, i.e., one byte can be received over the bus while
	 * the previous one is transmitted over MIDI.
	 * (The value here is adjusted for midi_ratelimit_per_packet().)
	 */
	p->midi_fifo_limit = rate - MIDI_BYTES_PER_SECOND * s->syt_interval + 1;

	return 0;
}

static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
			  __be32 *buffer, unsigned int frames)
{
	struct amdtp_dot *p = s->protocol;
	struct snd_pcm_runtime *runtime = pcm->runtime;
	unsigned int channels, remaining_frames, i, c;
	const u32 *src;

	channels = p->pcm_channels;
	src = (void *)runtime->dma_area +
			frames_to_bytes(runtime, s->pcm_buffer_pointer);
	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;

	buffer++;
	for (i = 0; i < frames; ++i) {
		for (c = 0; c < channels; ++c) {
			buffer[c] = cpu_to_be32((*src >> 8) | 0x40000000);
			dot_encode_step(&p->state, &buffer[c]);
			src++;
		}
		buffer += s->data_block_quadlets;
		if (--remaining_frames == 0)
			src = (void *)runtime->dma_area;
	}
}

static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
			 __be32 *buffer, unsigned int frames)
{
	struct amdtp_dot *p = s->protocol;
	struct snd_pcm_runtime *runtime = pcm->runtime;
	unsigned int channels, remaining_frames, i, c;
	u32 *dst;

	channels = p->pcm_channels;
	dst  = (void *)runtime->dma_area +
			frames_to_bytes(runtime, s->pcm_buffer_pointer);
	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;

	buffer++;
	for (i = 0; i < frames; ++i) {
		for (c = 0; c < channels; ++c) {
			*dst = be32_to_cpu(buffer[c]) << 8;
			dst++;
		}
		buffer += s->data_block_quadlets;
		if (--remaining_frames == 0)
			dst = (void *)runtime->dma_area;
	}
}

static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
			      unsigned int data_blocks)
{
	struct amdtp_dot *p = s->protocol;
	unsigned int channels, i, c;

	channels = p->pcm_channels;

	buffer++;
	for (i = 0; i < data_blocks; ++i) {
		for (c = 0; c < channels; ++c)
			buffer[c] = cpu_to_be32(0x40000000);
		buffer += s->data_block_quadlets;
	}
}

static bool midi_ratelimit_per_packet(struct amdtp_stream *s, unsigned int port)
{
	struct amdtp_dot *p = s->protocol;
	int used;

	used = p->midi_fifo_used[port];
	if (used == 0)
		return true;

	used -= MIDI_BYTES_PER_SECOND * s->syt_interval;
	used = max(used, 0);
	p->midi_fifo_used[port] = used;

	return used < p->midi_fifo_limit;
}

static inline void midi_use_bytes(struct amdtp_stream *s,
				  unsigned int port, unsigned int count)
{
	struct amdtp_dot *p = s->protocol;

	p->midi_fifo_used[port] += amdtp_rate_table[s->sfc] * count;
}

static void write_midi_messages(struct amdtp_stream *s, __be32 *buffer,
				unsigned int data_blocks)
{
	struct amdtp_dot *p = s->protocol;
	unsigned int f, port;
	int len;
	u8 *b;

	for (f = 0; f < data_blocks; f++) {
		port = (s->data_block_counter + f) % 8;
		b = (u8 *)&buffer[0];

		len = 0;
		if (port < MAX_MIDI_PORTS &&
		    midi_ratelimit_per_packet(s, port) &&
		    p->midi[port] != NULL)
			len = snd_rawmidi_transmit(p->midi[port], b + 1, 2);

		if (len > 0) {
			/*
			 * Upper 4 bits of LSB represent port number.
			 * - 0000b: physical MIDI port 1.
			 * - 0010b: physical MIDI port 2.
			 * - 1110b: console MIDI port.
			 */
			if (port == 2)
				b[3] = 0xe0;
			else if (port == 1)
				b[3] = 0x20;
			else
				b[3] = 0x00;
			b[3] |= len;
			midi_use_bytes(s, port, len);
		} else {
			b[1] = 0;
			b[2] = 0;
			b[3] = 0;
		}
		b[0] = 0x80;

		buffer += s->data_block_quadlets;
	}
}

static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
			       unsigned int data_blocks)
{
	struct amdtp_dot *p = s->protocol;
	unsigned int f, port, len;
	u8 *b;

	for (f = 0; f < data_blocks; f++) {
		b = (u8 *)&buffer[0];

		len = b[3] & 0x0f;
		if (len > 0) {
			/*
			 * Upper 4 bits of LSB represent port number.
			 * - 0000b: physical MIDI port 1. Use port 0.
			 * - 1110b: console MIDI port. Use port 2.
			 */
			if (b[3] >> 4 > 0)
				port = 2;
			else
				port = 0;

			if (port < MAX_MIDI_PORTS && p->midi[port])
				snd_rawmidi_receive(p->midi[port], b + 1, len);
		}

		buffer += s->data_block_quadlets;
	}
}

int amdtp_dot_add_pcm_hw_constraints(struct amdtp_stream *s,
				     struct snd_pcm_runtime *runtime)
{
	int err;

	/* This protocol delivers 24 bit data in 32bit data channel. */
	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
	if (err < 0)
		return err;

	return amdtp_stream_add_pcm_hw_constraints(s, runtime);
}

void amdtp_dot_midi_trigger(struct amdtp_stream *s, unsigned int port,
			  struct snd_rawmidi_substream *midi)
{
	struct amdtp_dot *p = s->protocol;

	if (port < MAX_MIDI_PORTS)
		WRITE_ONCE(p->midi[port], midi);
}

static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
					   __be32 *buffer,
					   unsigned int data_blocks,
					   unsigned int *syt)
{
	struct snd_pcm_substream *pcm;
	unsigned int pcm_frames;

	pcm = READ_ONCE(s->pcm);
	if (pcm) {
		read_pcm_s32(s, pcm, buffer, data_blocks);
		pcm_frames = data_blocks;
	} else {
		pcm_frames = 0;
	}

	read_midi_messages(s, buffer, data_blocks);

	return pcm_frames;
}

static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
					   __be32 *buffer,
					   unsigned int data_blocks,
					   unsigned int *syt)
{
	struct snd_pcm_substream *pcm;
	unsigned int pcm_frames;

	pcm = READ_ONCE(s->pcm);
	if (pcm) {
		write_pcm_s32(s, pcm, buffer, data_blocks);
		pcm_frames = data_blocks;
	} else {
		write_pcm_silence(s, buffer, data_blocks);
		pcm_frames = 0;
	}

	write_midi_messages(s, buffer, data_blocks);

	return pcm_frames;
}

int amdtp_dot_init(struct amdtp_stream *s, struct fw_unit *unit,
		 enum amdtp_stream_direction dir)
{
	amdtp_stream_process_data_blocks_t process_data_blocks;
	enum cip_flags flags;

	/* Use different mode between incoming/outgoing. */
	if (dir == AMDTP_IN_STREAM) {
		flags = CIP_NONBLOCKING;
		process_data_blocks = process_tx_data_blocks;
	} else {
		flags = CIP_BLOCKING;
		process_data_blocks = process_rx_data_blocks;
	}

	return amdtp_stream_init(s, unit, dir, flags, CIP_FMT_AM,
				 process_data_blocks, sizeof(struct amdtp_dot));
}

void amdtp_dot_reset(struct amdtp_stream *s)
{
	struct amdtp_dot *p = s->protocol;

	p->state.carry = 0x00;
	p->state.idx = 0x00;
	p->state.off = 0;
}
Commit	Line	Data
163ae6f3 TS	1	/*
	2	* amdtp-dot.c - a part of driver for Digidesign Digi 002/003 family
	3	*
	4	* Copyright (c) 2014-2015 Takashi Sakamoto
	5	* Copyright (C) 2012 Robin Gareus <robin@gareus.org>
	6	* Copyright (C) 2012 Damien Zammit <damien@zamaudio.com>
	7	*
	8	* Licensed under the terms of the GNU General Public License, version 2.
	9	*/
	10
	11	#include <sound/pcm.h>
	12	#include "digi00x.h"
	13
	14	#define CIP_FMT_AM 0x10
	15
	16	/* 'Clock-based rate control mode' is just supported. */
	17	#define AMDTP_FDF_AM824 0x00
	18
9dc5d31c TS	19	/*
	20	* Nominally 3125 bytes/second, but the MIDI port's clock might be
	21	* 1% too slow, and the bus clock 100 ppm too fast.
	22	*/
	23	#define MIDI_BYTES_PER_SECOND 3093
	24
	25	/*
	26	* Several devices look only at the first eight data blocks.
	27	* In any case, this is more than enough for the MIDI data rate.
	28	*/
	29	#define MAX_MIDI_RX_BLOCKS 8
	30
8820a4cf TS	31	/* 3 = MAX(DOT_MIDI_IN_PORTS, DOT_MIDI_OUT_PORTS) + 1. */
	32	#define MAX_MIDI_PORTS 3
	33
163ae6f3 TS	34	/*
	35	* The double-oh-three algorithm was discovered by Robin Gareus and Damien
	36	* Zammit in 2012, with reverse-engineering for Digi 003 Rack.
	37	*/
	38	struct dot_state {
17385a38 TS	39	u8 carry;
17385a38 TS	40	u8 idx;
163ae6f3 TS	41	unsigned int off;
	42	};
	43
	44	struct amdtp_dot {
	45	unsigned int pcm_channels;
	46	struct dot_state state;
	47
8820a4cf TS	48	struct snd_rawmidi_substream *midi[MAX_MIDI_PORTS];
8820a4cf TS	49	int midi_fifo_used[MAX_MIDI_PORTS];
9dc5d31c	50	int midi_fifo_limit;
163ae6f3 TS	51	};
	52
	53	/*
	54	* double-oh-three look up table
	55	*
	56	* @param idx index byte (audio-sample data) 0x00..0xff
	57	* @param off channel offset shift
	58	* @return salt to XOR with given data
	59	*/
	60	#define BYTE_PER_SAMPLE (4)
	61	#define MAGIC_DOT_BYTE (2)
	62	#define MAGIC_BYTE_OFF(x) (((x) * BYTE_PER_SAMPLE) + MAGIC_DOT_BYTE)
b8cb3750	63	static u8 dot_scrt(const u8 idx, const unsigned int off)
163ae6f3 TS	64	{
	65	/*
	66	* the length of the added pattern only depends on the lower nibble
	67	* of the last non-zero data
	68	*/
17385a38 TS	69	static const u8 len[16] = {0, 1, 3, 5, 7, 9, 11, 13, 14,
17385a38 TS	70	12, 10, 8, 6, 4, 2, 0};
163ae6f3 TS	71
	72	/*
	73	* the lower nibble of the salt. Interleaved sequence.
	74	* this is walked backwards according to len[]
	75	*/
17385a38 TS	76	static const u8 nib[15] = {0x8, 0x7, 0x9, 0x6, 0xa, 0x5, 0xb, 0x4,
17385a38 TS	77	0xc, 0x3, 0xd, 0x2, 0xe, 0x1, 0xf};
163ae6f3 TS	78
163ae6f3 TS	79	/* circular list for the salt's hi nibble. */
17385a38 TS	80	static const u8 hir[15] = {0x0, 0x6, 0xf, 0x8, 0x7, 0x5, 0x3, 0x4,
17385a38 TS	81	0xc, 0xd, 0xe, 0x1, 0x2, 0xb, 0xa};
163ae6f3 TS	82
	83	/*
	84	* start offset for upper nibble mapping.
	85	* note: 9 is /special/. In the case where the high nibble == 0x9,
	86	* hir[] is not used and - coincidentally - the salt's hi nibble is
	87	* 0x09 regardless of the offset.
	88	*/
17385a38 TS	89	static const u8 hio[16] = {0, 11, 12, 6, 7, 5, 1, 4,
17385a38 TS	90	3, 0x00, 14, 13, 8, 9, 10, 2};
163ae6f3	91
17385a38 TS	92	const u8 ln = idx & 0xf;
	93	const u8 hn = (idx >> 4) & 0xf;
	94	const u8 hr = (hn == 0x9) ? 0x9 : hir[(hio[hn] + off) % 15];
163ae6f3 TS	95
	96	if (len[ln] < off)
	97	return 0x00;
	98
	99	return ((nib[14 + off - len[ln]]) \| (hr << 4));
	100	}
	101
	102	static void dot_encode_step(struct dot_state state, __be32 const buffer)
	103	{
17385a38	104	u8 * const data = (u8 *) buffer;
163ae6f3 TS	105
	106	if (data[MAGIC_DOT_BYTE] != 0x00) {
	107	state->off = 0;
	108	state->idx = data[MAGIC_DOT_BYTE] ^ state->carry;
	109	}
	110	data[MAGIC_DOT_BYTE] ^= state->carry;
	111	state->carry = dot_scrt(state->idx, ++(state->off));
	112	}
	113
	114	int amdtp_dot_set_parameters(struct amdtp_stream *s, unsigned int rate,
9dc5d31c	115	unsigned int pcm_channels)
163ae6f3 TS	116	{
	117	struct amdtp_dot *p = s->protocol;
	118	int err;
	119
	120	if (amdtp_stream_running(s))
	121	return -EBUSY;
	122
	123	/*
8820a4cf TS	124	* A first data channel is for MIDI messages, the rest is Multi Bit
8820a4cf TS	125	* Linear Audio data channel.
163ae6f3 TS	126	*/
	127	err = amdtp_stream_set_parameters(s, rate, pcm_channels + 1);
	128	if (err < 0)
	129	return err;
	130
	131	s->fdf = AMDTP_FDF_AM824 \| s->sfc;
	132
	133	p->pcm_channels = pcm_channels;
9dc5d31c	134
9dc5d31c TS	135	/*
	136	* We do not know the actual MIDI FIFO size of most devices. Just
	137	* assume two bytes, i.e., one byte can be received over the bus while
	138	* the previous one is transmitted over MIDI.
	139	* (The value here is adjusted for midi_ratelimit_per_packet().)
	140	*/
	141	p->midi_fifo_limit = rate - MIDI_BYTES_PER_SECOND * s->syt_interval + 1;
163ae6f3 TS	142
	143	return 0;
	144	}
	145
	146	static void write_pcm_s32(struct amdtp_stream s, struct snd_pcm_substream pcm,
	147	__be32 *buffer, unsigned int frames)
	148	{
	149	struct amdtp_dot *p = s->protocol;
	150	struct snd_pcm_runtime *runtime = pcm->runtime;
	151	unsigned int channels, remaining_frames, i, c;
	152	const u32 *src;
	153
	154	channels = p->pcm_channels;
	155	src = (void *)runtime->dma_area +
	156	frames_to_bytes(runtime, s->pcm_buffer_pointer);
	157	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
	158
	159	buffer++;
	160	for (i = 0; i < frames; ++i) {
	161	for (c = 0; c < channels; ++c) {
	162	buffer[c] = cpu_to_be32((*src >> 8) \| 0x40000000);
	163	dot_encode_step(&p->state, &buffer[c]);
	164	src++;
	165	}
	166	buffer += s->data_block_quadlets;
	167	if (--remaining_frames == 0)
	168	src = (void *)runtime->dma_area;
	169	}
	170	}
	171
163ae6f3 TS	172	static void read_pcm_s32(struct amdtp_stream s, struct snd_pcm_substream pcm,
	173	__be32 *buffer, unsigned int frames)
	174	{
	175	struct amdtp_dot *p = s->protocol;
	176	struct snd_pcm_runtime *runtime = pcm->runtime;
	177	unsigned int channels, remaining_frames, i, c;
	178	u32 *dst;
	179
	180	channels = p->pcm_channels;
	181	dst = (void *)runtime->dma_area +
	182	frames_to_bytes(runtime, s->pcm_buffer_pointer);
	183	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
	184
	185	buffer++;
	186	for (i = 0; i < frames; ++i) {
	187	for (c = 0; c < channels; ++c) {
	188	*dst = be32_to_cpu(buffer[c]) << 8;
	189	dst++;
	190	}
	191	buffer += s->data_block_quadlets;
	192	if (--remaining_frames == 0)
	193	dst = (void *)runtime->dma_area;
	194	}
	195	}
	196
	197	static void write_pcm_silence(struct amdtp_stream s, __be32 buffer,
	198	unsigned int data_blocks)
	199	{
	200	struct amdtp_dot *p = s->protocol;
	201	unsigned int channels, i, c;
	202
	203	channels = p->pcm_channels;
	204
	205	buffer++;
	206	for (i = 0; i < data_blocks; ++i) {
	207	for (c = 0; c < channels; ++c)
	208	buffer[c] = cpu_to_be32(0x40000000);
	209	buffer += s->data_block_quadlets;
	210	}
	211	}
	212
9dc5d31c TS	213	static bool midi_ratelimit_per_packet(struct amdtp_stream *s, unsigned int port)
	214	{
	215	struct amdtp_dot *p = s->protocol;
	216	int used;
	217
	218	used = p->midi_fifo_used[port];
	219	if (used == 0)
	220	return true;
	221
	222	used -= MIDI_BYTES_PER_SECOND * s->syt_interval;
	223	used = max(used, 0);
	224	p->midi_fifo_used[port] = used;
	225
	226	return used < p->midi_fifo_limit;
	227	}
	228
	229	static inline void midi_use_bytes(struct amdtp_stream *s,
	230	unsigned int port, unsigned int count)
	231	{
	232	struct amdtp_dot *p = s->protocol;
	233
	234	p->midi_fifo_used[port] += amdtp_rate_table[s->sfc] * count;
	235	}
	236
	237	static void write_midi_messages(struct amdtp_stream s, __be32 buffer,
	238	unsigned int data_blocks)
	239	{
	240	struct amdtp_dot *p = s->protocol;
	241	unsigned int f, port;
	242	int len;
	243	u8 *b;
	244
	245	for (f = 0; f < data_blocks; f++) {
	246	port = (s->data_block_counter + f) % 8;
	247	b = (u8 *)&buffer[0];
	248
	249	len = 0;
8820a4cf	250	if (port < MAX_MIDI_PORTS &&
9dc5d31c TS	251	midi_ratelimit_per_packet(s, port) &&
	252	p->midi[port] != NULL)
	253	len = snd_rawmidi_transmit(p->midi[port], b + 1, 2);
	254
	255	if (len > 0) {
8820a4cf TS	256	/*
	257	* Upper 4 bits of LSB represent port number.
	258	* - 0000b: physical MIDI port 1.
	259	* - 0010b: physical MIDI port 2.
	260	* - 1110b: console MIDI port.
	261	*/
	262	if (port == 2)
	263	b[3] = 0xe0;
	264	else if (port == 1)
	265	b[3] = 0x20;
	266	else
	267	b[3] = 0x00;
	268	b[3] \|= len;
9dc5d31c TS	269	midi_use_bytes(s, port, len);
	270	} else {
	271	b[1] = 0;
	272	b[2] = 0;
	273	b[3] = 0;
	274	}
	275	b[0] = 0x80;
	276
	277	buffer += s->data_block_quadlets;
	278	}
	279	}
	280
	281	static void read_midi_messages(struct amdtp_stream s, __be32 buffer,
	282	unsigned int data_blocks)
	283	{
	284	struct amdtp_dot *p = s->protocol;
	285	unsigned int f, port, len;
	286	u8 *b;
	287
	288	for (f = 0; f < data_blocks; f++) {
	289	b = (u8 *)&buffer[0];
9dc5d31c	290
8820a4cf TS	291	len = b[3] & 0x0f;
	292	if (len > 0) {
	293	/*
	294	* Upper 4 bits of LSB represent port number.
	295	* - 0000b: physical MIDI port 1. Use port 0.
	296	* - 1110b: console MIDI port. Use port 2.
	297	*/
	298	if (b[3] >> 4 > 0)
	299	port = 2;
	300	else
	301	port = 0;
	302
	303	if (port < MAX_MIDI_PORTS && p->midi[port])
	304	snd_rawmidi_receive(p->midi[port], b + 1, len);
	305	}
9dc5d31c TS	306
	307	buffer += s->data_block_quadlets;
	308	}
	309	}
	310
163ae6f3 TS	311	int amdtp_dot_add_pcm_hw_constraints(struct amdtp_stream *s,
	312	struct snd_pcm_runtime *runtime)
	313	{
	314	int err;
	315
	316	/* This protocol delivers 24 bit data in 32bit data channel. */
	317	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
	318	if (err < 0)
	319	return err;
	320
	321	return amdtp_stream_add_pcm_hw_constraints(s, runtime);
	322	}
	323
9dc5d31c TS	324	void amdtp_dot_midi_trigger(struct amdtp_stream *s, unsigned int port,
	325	struct snd_rawmidi_substream *midi)
	326	{
	327	struct amdtp_dot *p = s->protocol;
	328
8820a4cf	329	if (port < MAX_MIDI_PORTS)
6aa7de05	330	WRITE_ONCE(p->midi[port], midi);
9dc5d31c TS	331	}
9dc5d31c TS	332
163ae6f3 TS	333	static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
	334	__be32 *buffer,
	335	unsigned int data_blocks,
	336	unsigned int *syt)
	337	{
163ae6f3 TS	338	struct snd_pcm_substream *pcm;
	339	unsigned int pcm_frames;
	340
6aa7de05	341	pcm = READ_ONCE(s->pcm);
163ae6f3	342	if (pcm) {
a02cb8f8	343	read_pcm_s32(s, pcm, buffer, data_blocks);
163ae6f3 TS	344	pcm_frames = data_blocks;
	345	} else {
	346	pcm_frames = 0;
	347	}
	348
9dc5d31c	349	read_midi_messages(s, buffer, data_blocks);
163ae6f3 TS	350
	351	return pcm_frames;
	352	}
	353
	354	static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
	355	__be32 *buffer,
	356	unsigned int data_blocks,
	357	unsigned int *syt)
	358	{
163ae6f3 TS	359	struct snd_pcm_substream *pcm;
	360	unsigned int pcm_frames;
	361
6aa7de05	362	pcm = READ_ONCE(s->pcm);
163ae6f3	363	if (pcm) {
a02cb8f8	364	write_pcm_s32(s, pcm, buffer, data_blocks);
163ae6f3 TS	365	pcm_frames = data_blocks;
	366	} else {
	367	write_pcm_silence(s, buffer, data_blocks);
	368	pcm_frames = 0;
	369	}
	370
9dc5d31c	371	write_midi_messages(s, buffer, data_blocks);
163ae6f3 TS	372
	373	return pcm_frames;
	374	}
	375
	376	int amdtp_dot_init(struct amdtp_stream s, struct fw_unit unit,
	377	enum amdtp_stream_direction dir)
	378	{
	379	amdtp_stream_process_data_blocks_t process_data_blocks;
	380	enum cip_flags flags;
	381
	382	/* Use different mode between incoming/outgoing. */
	383	if (dir == AMDTP_IN_STREAM) {
62f00e40	384	flags = CIP_NONBLOCKING;
163ae6f3 TS	385	process_data_blocks = process_tx_data_blocks;
	386	} else {
	387	flags = CIP_BLOCKING;
	388	process_data_blocks = process_rx_data_blocks;
	389	}
	390
	391	return amdtp_stream_init(s, unit, dir, flags, CIP_FMT_AM,
	392	process_data_blocks, sizeof(struct amdtp_dot));
	393	}
	394
	395	void amdtp_dot_reset(struct amdtp_stream *s)
	396	{
	397	struct amdtp_dot *p = s->protocol;
	398
	399	p->state.carry = 0x00;
	400	p->state.idx = 0x00;
	401	p->state.off = 0;
	402	}