ALSA: firewire-lib: use circular linked list for context payload processing layer

The list of packet descriptor is passed to context payload processing
layer so that each driver can copy PCM frames, MIDI messages, and device
specific data between packet payload buffer and intermediate buffer for
user space application.

The list of packet descriptor was replaced by circular linked list in a
previous commit. This commit uses circular linked in context payload
processing layer as well.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230109021738.75543-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 26 insertions, 22 deletions

diff --git a/sound/firewire/motu/amdtp-motu.c b/sound/firewire/motu/amdtp-motu.c
index 2fb52f481d12..ea0063cec5fb 100644
--- a/sound/firewire/motu/amdtp-motu.c
+++ b/sound/firewire/motu/amdtp-motu.c
@@ -284,19 +284,19 @@ static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
 	}
 }
 
-static void probe_tracepoints_events(struct amdtp_stream *s,
-				     const struct pkt_desc *descs,
-				     unsigned int packets)
+static void probe_tracepoints_events(struct amdtp_stream *s, const struct pkt_desc *desc,
+				     unsigned int count)
 {
 	int i;
 
-	for (i = 0; i < packets; ++i) {
-		const struct pkt_desc *desc = descs + i;
+	for (i = 0; i < count; ++i) {
 		__be32 *buf = desc->ctx_payload;
 		unsigned int data_blocks = desc->data_blocks;
 
 		trace_data_block_sph(s, data_blocks, buf);
 		trace_data_block_message(s, data_blocks, buf);
+
+		desc = amdtp_stream_next_packet_desc(s, desc);
 	}
 }
 
@@ -329,12 +329,13 @@ static void cache_event_offsets(struct amdtp_motu_cache *cache, const __be32 *bu
 }
 
 static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
-					    const struct pkt_desc *descs,
-					    unsigned int packets,
+					    const struct pkt_desc *desc,
+					    unsigned int count,
 					    struct snd_pcm_substream *pcm)
 {
 	struct snd_motu *motu = container_of(s, struct snd_motu, tx_stream);
 	struct amdtp_motu *p = s->protocol;
+	const struct pkt_desc *cursor = desc;
 	unsigned int pcm_frames = 0;
 	int i;
 
@@ -342,8 +343,7 @@ static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 		p->cache->tx_cycle_count = (s->domain->processing_cycle.tx_start % CYCLES_PER_SECOND);
 
 	// For data block processing.
-	for (i = 0; i < packets; ++i) {
-		const struct pkt_desc *desc = descs + i;
+	for (i = 0; i < count; ++i) {
 		__be32 *buf = desc->ctx_payload;
 		unsigned int data_blocks = desc->data_blocks;
 
@@ -356,20 +356,20 @@ static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 
 		if (p->midi_ports)
 			read_midi_messages(s, buf, data_blocks);
-	}
 
-	if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP) {
-		snd_motu_register_dsp_message_parser_parse(motu, descs, packets,
-							   s->data_block_quadlets);
-	} else if (motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP) {
-		snd_motu_command_dsp_message_parser_parse(motu, descs, packets,
-							  s->data_block_quadlets);
+		desc = amdtp_stream_next_packet_desc(s, desc);
 	}
 
+	desc = cursor;
+	if (motu->spec->flags & SND_MOTU_SPEC_REGISTER_DSP)
+		snd_motu_register_dsp_message_parser_parse(s, desc, count);
+	else if (motu->spec->flags & SND_MOTU_SPEC_COMMAND_DSP)
+		snd_motu_command_dsp_message_parser_parse(s, desc, count);
+
 	// For tracepoints.
 	if (trace_data_block_sph_enabled() ||
 	    trace_data_block_message_enabled())
-		probe_tracepoints_events(s, descs, packets);
+		probe_tracepoints_events(s, desc, count);
 
 	return pcm_frames;
 }
@@ -397,11 +397,12 @@ static void write_sph(struct amdtp_motu_cache *cache, __be32 *buffer, unsigned i
 }
 
 static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
-					    const struct pkt_desc *descs,
-					    unsigned int packets,
+					    const struct pkt_desc *desc,
+					    unsigned int count,
 					    struct snd_pcm_substream *pcm)
 {
 	struct amdtp_motu *p = s->protocol;
+	const struct pkt_desc *cursor = desc;
 	unsigned int pcm_frames = 0;
 	int i;
 
@@ -409,8 +410,7 @@ static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
 		p->cache->rx_cycle_count = (s->domain->processing_cycle.rx_start % CYCLES_PER_SECOND);
 
 	// For data block processing.
-	for (i = 0; i < packets; ++i) {
-		const struct pkt_desc *desc = descs + i;
+	for (i = 0; i < count; ++i) {
 		__be32 *buf = desc->ctx_payload;
 		unsigned int data_blocks = desc->data_blocks;
 
@@ -425,12 +425,16 @@ static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
 			write_midi_messages(s, buf, data_blocks);
 
 		write_sph(p->cache, buf, data_blocks, s->data_block_quadlets);
+
+		desc = amdtp_stream_next_packet_desc(s, desc);
 	}
 
+	desc = cursor;
+
 	// For tracepoints.
 	if (trace_data_block_sph_enabled() ||
 	    trace_data_block_message_enabled())
-		probe_tracepoints_events(s, descs, packets);
+		probe_tracepoints_events(s, desc, count);
 
 	return pcm_frames;
 }