ALSA: firewire-lib: Add support for channel mapping

Some devices arrange the position of PCM/MIDI data channel in AMDTP packet.
This commit allows drivers to set channel mapping.

To be simple, the mapping table is an array with fixed length. Then the number
of channels for PCM is restricted by 64 channels.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 71 insertions, 47 deletions

diff --git a/sound/firewire/amdtp.c b/sound/firewire/amdtp.c
index 8498155c15a6..9cf81b2b4298 100644
--- a/sound/firewire/amdtp.c
+++ b/sound/firewire/amdtp.c
@@ -129,11 +129,12 @@ void amdtp_stream_set_parameters(struct amdtp_stream *s,
 		[CIP_SFC_176400] = 176400,
 		[CIP_SFC_192000] = 192000,
 	};
-	unsigned int sfc, midi_channels;
+	unsigned int i, sfc, midi_channels;
 
 	midi_channels = DIV_ROUND_UP(midi_ports, 8);
 
-	if (WARN_ON(amdtp_stream_running(s)) ||
+	if (WARN_ON(amdtp_stream_running(s)) |
+	    WARN_ON(pcm_channels > AMDTP_MAX_CHANNELS_FOR_PCM) |
 	    WARN_ON(midi_channels > AMDTP_MAX_CHANNELS_FOR_MIDI))
 		return;
 
@@ -148,11 +149,12 @@ sfc_found:
 	if (s->dual_wire) {
 		sfc -= 2;
 		rate /= 2;
-		pcm_channels *= 2;
+		s->pcm_channels = pcm_channels * 2;
+	} else {
+		s->pcm_channels = pcm_channels;
 	}
 	s->sfc = sfc;
-	s->data_block_quadlets = pcm_channels + midi_channels;
-	s->pcm_channels = pcm_channels;
+	s->data_block_quadlets = s->pcm_channels + midi_channels;
 	s->midi_ports = midi_ports;
 
 	s->syt_interval = amdtp_syt_intervals[sfc];
@@ -162,6 +164,11 @@ sfc_found:
 	if (s->flags & CIP_BLOCKING)
 		/* additional buffering needed to adjust for no-data packets */
 		s->transfer_delay += TICKS_PER_SECOND * s->syt_interval / rate;
+
+	/* init the position map for PCM and MIDI channels */
+	for (i = 0; i < pcm_channels; i++)
+		s->pcm_positions[i] = i;
+	s->midi_position = s->pcm_channels;
 }
 EXPORT_SYMBOL(amdtp_stream_set_parameters);
 
@@ -341,22 +348,21 @@ static void amdtp_write_s32(struct amdtp_stream *s,
 			    __be32 *buffer, unsigned int frames)
 {
 	struct snd_pcm_runtime *runtime = pcm->runtime;
-	unsigned int channels, remaining_frames, frame_step, i, c;
+	unsigned int channels, remaining_frames, i, c;
 	const u32 *src;
 
 	channels = s->pcm_channels;
 	src = (void *)runtime->dma_area +
 			frames_to_bytes(runtime, s->pcm_buffer_pointer);
 	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
-	frame_step = s->data_block_quadlets - channels;
 
 	for (i = 0; i < frames; ++i) {
 		for (c = 0; c < channels; ++c) {
-			*buffer = cpu_to_be32((*src >> 8) | 0x40000000);
+			buffer[s->pcm_positions[c]] =
+					cpu_to_be32((*src >> 8) | 0x40000000);
 			src++;
-			buffer++;
 		}
-		buffer += frame_step;
+		buffer += s->data_block_quadlets;
 		if (--remaining_frames == 0)
 			src = (void *)runtime->dma_area;
 	}
@@ -367,22 +373,21 @@ static void amdtp_write_s16(struct amdtp_stream *s,
 			    __be32 *buffer, unsigned int frames)
 {
 	struct snd_pcm_runtime *runtime = pcm->runtime;
-	unsigned int channels, remaining_frames, frame_step, i, c;
+	unsigned int channels, remaining_frames, i, c;
 	const u16 *src;
 
 	channels = s->pcm_channels;
 	src = (void *)runtime->dma_area +
 			frames_to_bytes(runtime, s->pcm_buffer_pointer);
 	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
-	frame_step = s->data_block_quadlets - channels;
 
 	for (i = 0; i < frames; ++i) {
 		for (c = 0; c < channels; ++c) {
-			*buffer = cpu_to_be32((*src << 8) | 0x40000000);
+			buffer[s->pcm_positions[c]] =
+					cpu_to_be32((*src << 8) | 0x40000000);
 			src++;
-			buffer++;
 		}
-		buffer += frame_step;
+		buffer += s->data_block_quadlets;
 		if (--remaining_frames == 0)
 			src = (void *)runtime->dma_area;
 	}
@@ -393,29 +398,29 @@ static void amdtp_write_s32_dualwire(struct amdtp_stream *s,
 				     __be32 *buffer, unsigned int frames)
 {
 	struct snd_pcm_runtime *runtime = pcm->runtime;
-	unsigned int channels, frame_adjust_1, frame_adjust_2, i, c;
+	unsigned int channels, remaining_frames, i, c;
 	const u32 *src;
 
-	channels = s->pcm_channels;
 	src = (void *)runtime->dma_area +
-			s->pcm_buffer_pointer * (runtime->frame_bits / 8);
-	frame_adjust_1 = channels - 1;
-	frame_adjust_2 = 1 - (s->data_block_quadlets - channels);
+			frames_to_bytes(runtime, s->pcm_buffer_pointer);
+	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
+	channels = s->pcm_channels / 2;
 
-	channels /= 2;
 	for (i = 0; i < frames; ++i) {
 		for (c = 0; c < channels; ++c) {
-			*buffer = cpu_to_be32((*src >> 8) | 0x40000000);
+			buffer[s->pcm_positions[c] * 2] =
+					cpu_to_be32((*src >> 8) | 0x40000000);
 			src++;
-			buffer += 2;
 		}
-		buffer -= frame_adjust_1;
+		buffer += 1;
 		for (c = 0; c < channels; ++c) {
-			*buffer = cpu_to_be32((*src >> 8) | 0x40000000);
+			buffer[s->pcm_positions[c] * 2] =
+					cpu_to_be32((*src >> 8) | 0x40000000);
 			src++;
-			buffer += 2;
 		}
-		buffer -= frame_adjust_2;
+		buffer += s->data_block_quadlets - 1;
+		if (--remaining_frames == 0)
+			src = (void *)runtime->dma_area;
 	}
 }
 
@@ -424,29 +429,29 @@ static void amdtp_write_s16_dualwire(struct amdtp_stream *s,
 				     __be32 *buffer, unsigned int frames)
 {
 	struct snd_pcm_runtime *runtime = pcm->runtime;
-	unsigned int channels, frame_adjust_1, frame_adjust_2, i, c;
+	unsigned int channels, remaining_frames, i, c;
 	const u16 *src;
 
-	channels = s->pcm_channels;
 	src = (void *)runtime->dma_area +
-			s->pcm_buffer_pointer * (runtime->frame_bits / 8);
-	frame_adjust_1 = channels - 1;
-	frame_adjust_2 = 1 - (s->data_block_quadlets - channels);
+			frames_to_bytes(runtime, s->pcm_buffer_pointer);
+	remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
+	channels = s->pcm_channels / 2;
 
-	channels /= 2;
 	for (i = 0; i < frames; ++i) {
 		for (c = 0; c < channels; ++c) {
-			*buffer = cpu_to_be32((*src << 8) | 0x40000000);
+			buffer[s->pcm_positions[c] * 2] =
+					cpu_to_be32((*src << 8) | 0x40000000);
 			src++;
-			buffer += 2;
 		}
-		buffer -= frame_adjust_1;
+		buffer += 1;
 		for (c = 0; c < channels; ++c) {
-			*buffer = cpu_to_be32((*src << 8) | 0x40000000);
+			buffer[s->pcm_positions[c] * 2] =
+					cpu_to_be32((*src << 8) | 0x40000000);
 			src++;
-			buffer += 2;
 		}
-		buffer -= frame_adjust_2;
+		buffer += s->data_block_quadlets - 1;
+		if (--remaining_frames == 0)
+			src = (void *)runtime->dma_area;
 	}
 }
 
@@ -465,7 +470,7 @@ static void amdtp_read_s32(struct amdtp_stream *s,
 
 	for (i = 0; i < frames; ++i) {
 		for (c = 0; c < channels; ++c) {
-			*dst = be32_to_cpu(buffer[c]) << 8;
+			*dst = be32_to_cpu(buffer[s->pcm_positions[c]]) << 8;
 			dst++;
 		}
 		buffer += s->data_block_quadlets;
@@ -489,12 +494,14 @@ static void amdtp_read_s32_dualwire(struct amdtp_stream *s,
 
 	for (i = 0; i < frames; ++i) {
 		for (c = 0; c < channels; ++c) {
-			*dst = be32_to_cpu(buffer[c * 2]) << 8;
+			*dst =
+			     be32_to_cpu(buffer[s->pcm_positions[c] * 2]) << 8;
 			dst++;
 		}
 		buffer += 1;
 		for (c = 0; c < channels; ++c) {
-			*dst = be32_to_cpu(buffer[c * 2]) << 8;
+			*dst =
+			     be32_to_cpu(buffer[s->pcm_positions[c] * 2]) << 8;
 			dst++;
 		}
 		buffer += s->data_block_quadlets - 1;
@@ -510,11 +517,26 @@ static void amdtp_fill_pcm_silence(struct amdtp_stream *s,
 
 	for (i = 0; i < frames; ++i) {
 		for (c = 0; c < s->pcm_channels; ++c)
-			buffer[c] = cpu_to_be32(0x40000000);
+			buffer[s->pcm_positions[c]] = cpu_to_be32(0x40000000);
 		buffer += s->data_block_quadlets;
 	}
 }
 
+static void amdtp_fill_pcm_silence_dualwire(struct amdtp_stream *s,
+					   __be32 *buffer, unsigned int frames)
+{
+	unsigned int i, c, channels;
+
+	channels = s->pcm_channels / 2;
+	for (i = 0; i < frames; ++i) {
+		for (c = 0; c < channels; ++c) {
+			buffer[s->pcm_positions[c] * 2] =
+			buffer[s->pcm_positions[c] * 2 + 1] =
+						cpu_to_be32(0x40000000);
+		}
+		buffer += s->data_block_quadlets;
+	}
+}
 static void amdtp_fill_midi(struct amdtp_stream *s,
 			    __be32 *buffer, unsigned int frames)
 {
@@ -522,8 +544,8 @@ static void amdtp_fill_midi(struct amdtp_stream *s,
 	u8 *b;
 
 	for (f = 0; f < frames; f++) {
-		buffer[s->pcm_channels + 1] = 0;
-		b = (u8 *)&buffer[s->pcm_channels + 1];
+		buffer[s->midi_position] = 0;
+		b = (u8 *)&buffer[s->midi_position];
 
 		port = (s->data_block_counter + f) % 8;
 		if ((s->midi[port] == NULL) ||
@@ -545,7 +567,7 @@ static void amdtp_pull_midi(struct amdtp_stream *s,
 
 	for (f = 0; f < frames; f++) {
 		port = (s->data_block_counter + f) % 8;
-		b = (u8 *)&buffer[s->pcm_channels + 1];
+		b = (u8 *)&buffer[s->midi_position];
 
 		len = b[0] - 0x80;
 		if ((1 <= len) &&  (len <= 3) && (s->midi[port]))
@@ -652,6 +674,8 @@ static void handle_out_packet(struct amdtp_stream *s, unsigned int syt)
 	pcm = ACCESS_ONCE(s->pcm);
 	if (pcm)
 		s->transfer_samples(s, pcm, buffer, data_blocks);
+	else if (s->dual_wire)
+		amdtp_fill_pcm_silence_dualwire(s, buffer, data_blocks);
 	else
 		amdtp_fill_pcm_silence(s, buffer, data_blocks);
 	if (s->midi_ports)
@@ -683,7 +707,7 @@ static void handle_in_packet(struct amdtp_stream *s,
 
 	/*
 	 * This module supports 'Two-quadlet CIP header with SYT field'.
-	 * For convinience, also check FMT field is AM824 or not.
+	 * For convenience, also check FMT field is AM824 or not.
 	 */
 	if (((cip_header[0] & CIP_EOH_MASK) == CIP_EOH) ||
 	    ((cip_header[1] & CIP_EOH_MASK) != CIP_EOH) ||