1 files changed, 25 insertions, 17 deletions

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index 4e2f2bb7879f..e0faa6601966 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -526,7 +526,7 @@ static void build_it_pkt_header(struct amdtp_stream *s, unsigned int cycle,
 	}
 
 	trace_amdtp_packet(s, cycle, cip_header, payload_length, data_blocks,
-			   data_block_counter, index);
+			   data_block_counter, s->packet_index, index);
 }
 
 static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
@@ -630,21 +630,27 @@ static int parse_ir_ctx_header(struct amdtp_stream *s, unsigned int cycle,
 			       unsigned int *payload_length,
 			       unsigned int *data_blocks,
 			       unsigned int *data_block_counter,
-			       unsigned int *syt, unsigned int index)
+			       unsigned int *syt, unsigned int packet_index, unsigned int index)
 {
 	const __be32 *cip_header;
+	unsigned int cip_header_size;
 	int err;
 
 	*payload_length = be32_to_cpu(ctx_header[0]) >> ISO_DATA_LENGTH_SHIFT;
-	if (*payload_length > s->ctx_data.tx.ctx_header_size +
-					s->ctx_data.tx.max_ctx_payload_length) {
+
+	if (!(s->flags & CIP_NO_HEADER))
+		cip_header_size = 8;
+	else
+		cip_header_size = 0;
+
+	if (*payload_length > cip_header_size + s->ctx_data.tx.max_ctx_payload_length) {
 		dev_err(&s->unit->device,
 			"Detect jumbo payload: %04x %04x\n",
-			*payload_length, s->ctx_data.tx.max_ctx_payload_length);
+			*payload_length, cip_header_size + s->ctx_data.tx.max_ctx_payload_length);
 		return -EIO;
 	}
 
-	if (!(s->flags & CIP_NO_HEADER)) {
+	if (cip_header_size > 0) {
 		cip_header = ctx_header + 2;
 		err = check_cip_header(s, cip_header, *payload_length,
 				       data_blocks, data_block_counter, syt);
@@ -662,7 +668,7 @@ static int parse_ir_ctx_header(struct amdtp_stream *s, unsigned int cycle,
 	}
 
 	trace_amdtp_packet(s, cycle, cip_header, *payload_length, *data_blocks,
-			   *data_block_counter, index);
+			   *data_block_counter, packet_index, index);
 
 	return err;
 }
@@ -701,12 +707,13 @@ static int generate_device_pkt_descs(struct amdtp_stream *s,
 				     unsigned int packets)
 {
 	unsigned int dbc = s->data_block_counter;
+	unsigned int packet_index = s->packet_index;
+	unsigned int queue_size = s->queue_size;
 	int i;
 	int err;
 
 	for (i = 0; i < packets; ++i) {
 		struct pkt_desc *desc = descs + i;
-		unsigned int index = (s->packet_index + i) % s->queue_size;
 		unsigned int cycle;
 		unsigned int payload_length;
 		unsigned int data_blocks;
@@ -715,7 +722,7 @@ static int generate_device_pkt_descs(struct amdtp_stream *s,
 		cycle = compute_cycle_count(ctx_header[1]);
 
 		err = parse_ir_ctx_header(s, cycle, ctx_header, &payload_length,
-					  &data_blocks, &dbc, &syt, i);
+					  &data_blocks, &dbc, &syt, packet_index, i);
 		if (err < 0)
 			return err;
 
@@ -723,13 +730,15 @@ static int generate_device_pkt_descs(struct amdtp_stream *s,
 		desc->syt = syt;
 		desc->data_blocks = data_blocks;
 		desc->data_block_counter = dbc;
-		desc->ctx_payload = s->buffer.packets[index].buffer;
+		desc->ctx_payload = s->buffer.packets[packet_index].buffer;
 
 		if (!(s->flags & CIP_DBC_IS_END_EVENT))
 			dbc = (dbc + desc->data_blocks) & 0xff;
 
 		ctx_header +=
 			s->ctx_data.tx.ctx_header_size / sizeof(*ctx_header);
+
+		packet_index = (packet_index + 1) % queue_size;
 	}
 
 	s->data_block_counter = dbc;
@@ -1065,23 +1074,22 @@ static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed,
 		s->data_block_counter = 0;
 	}
 
-	/* initialize packet buffer */
+	// initialize packet buffer.
+	max_ctx_payload_size = amdtp_stream_get_max_payload(s);
 	if (s->direction == AMDTP_IN_STREAM) {
 		dir = DMA_FROM_DEVICE;
 		type = FW_ISO_CONTEXT_RECEIVE;
-		if (!(s->flags & CIP_NO_HEADER))
+		if (!(s->flags & CIP_NO_HEADER)) {
+			max_ctx_payload_size -= 8;
 			ctx_header_size = IR_CTX_HEADER_SIZE_CIP;
-		else
+		} else {
 			ctx_header_size = IR_CTX_HEADER_SIZE_NO_CIP;
-
-		max_ctx_payload_size = amdtp_stream_get_max_payload(s) -
-				       ctx_header_size;
+		}
 	} else {
 		dir = DMA_TO_DEVICE;
 		type = FW_ISO_CONTEXT_TRANSMIT;
 		ctx_header_size = 0;	// No effect for IT context.
 
-		max_ctx_payload_size = amdtp_stream_get_max_payload(s);
 		if (!(s->flags & CIP_NO_HEADER))
 			max_ctx_payload_size -= IT_PKT_HEADER_SIZE_CIP;
 	}