diff --git a/sound/firewire/amdtp-am824.c b/sound/firewire/amdtp-am824.c
index 21068b23d528..ff089ffa3374 100644
--- a/sound/firewire/amdtp-am824.c
+++ b/sound/firewire/amdtp-am824.c
@@ -336,44 +336,46 @@ static void read_midi_messages(struct amdtp_stream *s, __be32 *buffer,
 }
 
 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
 	struct amdtp_am824 *p = s->protocol;
-	struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
 	unsigned int pcm_frames;
 
 	if (pcm) {
-		write_pcm_s32(s, pcm, buffer, data_blocks);
-		pcm_frames = data_blocks * p->frame_multiplier;
+		write_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = desc->data_blocks * p->frame_multiplier;
 	} else {
-		write_pcm_silence(s, buffer, data_blocks);
+		write_pcm_silence(s, desc->ctx_payload, desc->data_blocks);
 		pcm_frames = 0;
 	}
 
-	if (p->midi_ports)
-		write_midi_messages(s, buffer, data_blocks, data_block_counter);
+	if (p->midi_ports) {
+		write_midi_messages(s, desc->ctx_payload, desc->data_blocks,
+				    desc->data_block_counter);
+	}
 
 	return pcm_frames;
 }
 
 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
 	struct amdtp_am824 *p = s->protocol;
-	struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
 	unsigned int pcm_frames;
 
 	if (pcm) {
-		read_pcm_s32(s, pcm, buffer, data_blocks);
-		pcm_frames = data_blocks * p->frame_multiplier;
+		read_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = desc->data_blocks * p->frame_multiplier;
 	} else {
 		pcm_frames = 0;
 	}
 
-	if (p->midi_ports)
-		read_midi_messages(s, buffer, data_blocks, data_block_counter);
+	if (p->midi_ports) {
+		read_midi_messages(s, desc->ctx_payload, desc->data_blocks,
+				   desc->data_block_counter);
+	}
 
 	return pcm_frames;
 }
diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index 573265113a6f..db2feb68105c 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -768,13 +768,11 @@ static void process_ctx_payloads(struct amdtp_stream *s,
 
 	for (i = 0; i < packets; ++i) {
 		const struct pkt_desc *desc = descs + i;
-		struct snd_pcm_substream *pcm;
+		struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
 		unsigned int pcm_frames;
 
-		pcm_frames = s->process_data_blocks(s, desc->ctx_payload,
-				desc->data_blocks, desc->data_block_counter);
+		pcm_frames = s->process_data_blocks(s, desc, pcm);
 
-		pcm = READ_ONCE(s->pcm);
 		if (pcm && pcm_frames > 0)
 			update_pcm_pointers(s, pcm, pcm_frames);
 	}
diff --git a/sound/firewire/amdtp-stream.h b/sound/firewire/amdtp-stream.h
index 73c492c9a5d5..0e5b85100a04 100644
--- a/sound/firewire/amdtp-stream.h
+++ b/sound/firewire/amdtp-stream.h
@@ -105,9 +105,8 @@ struct pkt_desc {
 struct amdtp_stream;
 typedef unsigned int (*amdtp_stream_process_data_blocks_t)(
 						struct amdtp_stream *s,
-						__be32 *buffer,
-						unsigned int data_blocks,
-						unsigned int data_block_counter);
+						const struct pkt_desc *desc,
+						struct snd_pcm_substream *pcm);
 struct amdtp_stream {
 	struct fw_unit *unit;
 	enum cip_flags flags;
diff --git a/sound/firewire/digi00x/amdtp-dot.c b/sound/firewire/digi00x/amdtp-dot.c
index c296d1017ed3..83ac4b37f26d 100644
--- a/sound/firewire/digi00x/amdtp-dot.c
+++ b/sound/firewire/digi00x/amdtp-dot.c
@@ -330,42 +330,39 @@ void amdtp_dot_midi_trigger(struct amdtp_stream *s, unsigned int port,
 }
 
 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
-	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;
+		read_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = desc->data_blocks;
 	} else {
 		pcm_frames = 0;
 	}
 
-	read_midi_messages(s, buffer, data_blocks);
+	read_midi_messages(s, desc->ctx_payload, desc->data_blocks);
 
 	return pcm_frames;
 }
 
 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
-	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;
+		write_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = desc->data_blocks;
 	} else {
-		write_pcm_silence(s, buffer, data_blocks);
+		write_pcm_silence(s, desc->ctx_payload, desc->data_blocks);
 		pcm_frames = 0;
 	}
 
-	write_midi_messages(s, buffer, data_blocks, data_block_counter);
+	write_midi_messages(s, desc->ctx_payload, desc->data_blocks,
+			    desc->data_block_counter);
 
 	return pcm_frames;
 }
diff --git a/sound/firewire/fireface/amdtp-ff.c b/sound/firewire/fireface/amdtp-ff.c
index 31a60dff94ac..c36232fc4d3e 100644
--- a/sound/firewire/fireface/amdtp-ff.c
+++ b/sound/firewire/fireface/amdtp-ff.c
@@ -103,17 +103,18 @@ int amdtp_ff_add_pcm_hw_constraints(struct amdtp_stream *s,
 }
 
 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
-	struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
 	unsigned int pcm_frames;
 
 	if (pcm) {
-		write_pcm_s32(s, pcm, (__le32 *)buffer, data_blocks);
-		pcm_frames = data_blocks;
+		write_pcm_s32(s, pcm, (__le32 *)desc->ctx_payload,
+			      desc->data_blocks);
+		pcm_frames = desc->data_blocks;
 	} else {
-		write_pcm_silence(s, (__le32 *)buffer, data_blocks);
+		write_pcm_silence(s, (__le32 *)desc->ctx_payload,
+				  desc->data_blocks);
 		pcm_frames = 0;
 	}
 
@@ -121,15 +122,15 @@ static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
 }
 
 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
-	struct snd_pcm_substream *pcm = READ_ONCE(s->pcm);
 	unsigned int pcm_frames;
 
 	if (pcm) {
-		read_pcm_s32(s, pcm, (__le32 *)buffer, data_blocks);
-		pcm_frames = data_blocks;
+		read_pcm_s32(s, pcm, (__le32 *)desc->ctx_payload,
+			     desc->data_blocks);
+		pcm_frames = desc->data_blocks;
 	} else {
 		pcm_frames = 0;
 	}
diff --git a/sound/firewire/motu/amdtp-motu.c b/sound/firewire/motu/amdtp-motu.c
index 30d5f87119cc..36ee2c1dd667 100644
--- a/sound/firewire/motu/amdtp-motu.c
+++ b/sound/firewire/motu/amdtp-motu.c
@@ -299,23 +299,27 @@ static void __maybe_unused copy_message(u64 *frames, __be32 *buffer,
 }
 
 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
 	struct amdtp_motu *p = s->protocol;
-	struct snd_pcm_substream *pcm;
+	unsigned int pcm_frames;
 
-	trace_data_block_sph(s, data_blocks, buffer);
-	trace_data_block_message(s, data_blocks, buffer);
+	trace_data_block_sph(s, desc->data_blocks, desc->ctx_payload);
+	trace_data_block_message(s, desc->data_blocks, desc->ctx_payload);
 
 	if (p->midi_ports)
-		read_midi_messages(s, buffer, data_blocks);
+		read_midi_messages(s, desc->ctx_payload, desc->data_blocks);
 
-	pcm = READ_ONCE(s->pcm);
-	if (data_blocks > 0 && pcm)
-		read_pcm_s32(s, pcm->runtime, buffer, data_blocks);
+	if (pcm) {
+		read_pcm_s32(s, pcm->runtime, desc->ctx_payload,
+			     desc->data_blocks);
+		pcm_frames = desc->data_blocks;
+	} else {
+		pcm_frames = 0;
+	}
 
-	return data_blocks;
+	return pcm_frames;
 }
 
 static inline void compute_next_elapse_from_start(struct amdtp_motu *p)
@@ -361,29 +365,32 @@ static void write_sph(struct amdtp_stream *s, __be32 *buffer,
 }
 
 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
 	struct amdtp_motu *p = (struct amdtp_motu *)s->protocol;
-	struct snd_pcm_substream *pcm;
+	unsigned int pcm_frames;
 
 	/* TODO: how to interact control messages between userspace? */
 
 	if (p->midi_ports)
-		write_midi_messages(s, buffer, data_blocks);
+		write_midi_messages(s, desc->ctx_payload, desc->data_blocks);
 
-	pcm = READ_ONCE(s->pcm);
-	if (pcm)
-		write_pcm_s32(s, pcm->runtime, buffer, data_blocks);
-	else
-		write_pcm_silence(s, buffer, data_blocks);
+	if (pcm) {
+		write_pcm_s32(s, pcm->runtime, desc->ctx_payload,
+			      desc->data_blocks);
+		pcm_frames = desc->data_blocks;
+	} else {
+		write_pcm_silence(s, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = 0;
+	}
 
-	write_sph(s, buffer, data_blocks);
+	write_sph(s, desc->ctx_payload, desc->data_blocks);
 
-	trace_data_block_sph(s, data_blocks, buffer);
-	trace_data_block_message(s, data_blocks, buffer);
+	trace_data_block_sph(s, desc->data_blocks, desc->ctx_payload);
+	trace_data_block_message(s, desc->data_blocks, desc->ctx_payload);
 
-	return data_blocks;
+	return pcm_frames;
 }
 
 int amdtp_motu_init(struct amdtp_stream *s, struct fw_unit *unit,
diff --git a/sound/firewire/tascam/amdtp-tascam.c b/sound/firewire/tascam/amdtp-tascam.c
index bc1f2d2120b4..970b1c4a8ea6 100644
--- a/sound/firewire/tascam/amdtp-tascam.c
+++ b/sound/firewire/tascam/amdtp-tascam.c
@@ -166,33 +166,38 @@ static void read_status_messages(struct amdtp_stream *s,
 }
 
 static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
-	struct snd_pcm_substream *pcm;
+	unsigned int pcm_frames;
 
-	pcm = READ_ONCE(s->pcm);
-	if (data_blocks > 0 && pcm)
-		read_pcm_s32(s, pcm, buffer, data_blocks);
+	if (pcm) {
+		read_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = desc->data_blocks;
+	} else {
+		pcm_frames = 0;
+	}
 
-	read_status_messages(s, buffer, data_blocks);
+	read_status_messages(s, desc->ctx_payload, desc->data_blocks);
 
-	return data_blocks;
+	return pcm_frames;
 }
 
 static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
-				__be32 *buffer, unsigned int data_blocks,
-				unsigned int data_block_counter)
+					   const struct pkt_desc *desc,
+					   struct snd_pcm_substream *pcm)
 {
-	struct snd_pcm_substream *pcm;
+	unsigned int pcm_frames;
 
-	pcm = READ_ONCE(s->pcm);
-	if (pcm)
-		write_pcm_s32(s, pcm, buffer, data_blocks);
-	else
-		write_pcm_silence(s, buffer, data_blocks);
+	if (pcm) {
+		write_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = desc->data_blocks;
+	} else {
+		write_pcm_silence(s, desc->ctx_payload, desc->data_blocks);
+		pcm_frames = 0;
+	}
 
-	return data_blocks;
+	return pcm_frames;
 }
 
 int amdtp_tscm_init(struct amdtp_stream *s, struct fw_unit *unit,