diff options
| -rw-r--r-- | sound/firewire/amdtp-stream.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c index 78b62a452d56..af5c3629f1ac 100644 --- a/sound/firewire/amdtp-stream.c +++ b/sound/firewire/amdtp-stream.c @@ -723,7 +723,8 @@ static inline u32 compute_ohci_it_cycle(const __be32 ctx_header_tstamp, static int generate_device_pkt_descs(struct amdtp_stream *s, struct pkt_desc *descs, const __be32 *ctx_header, - unsigned int packets) + unsigned int packets, + unsigned int *desc_count) { unsigned int next_cycle = s->next_cycle; unsigned int dbc = s->data_block_counter; @@ -732,8 +733,9 @@ static int generate_device_pkt_descs(struct amdtp_stream *s, int i; int err; + *desc_count = 0; for (i = 0; i < packets; ++i) { - struct pkt_desc *desc = descs + i; + struct pkt_desc *desc = descs + *desc_count; unsigned int cycle; bool lost; unsigned int data_blocks; @@ -745,11 +747,25 @@ static int generate_device_pkt_descs(struct amdtp_stream *s, if (s->flags & CIP_NO_HEADER) { // Fireface skips transmission just for an isoc cycle corresponding // to empty packet. + unsigned int prev_cycle = next_cycle; + next_cycle = increment_ohci_cycle_count(next_cycle, 1); lost = (next_cycle != cycle); + if (!lost) { + // Prepare a description for the skipped cycle for + // sequence replay. + desc->cycle = prev_cycle; + desc->syt = 0; + desc->data_blocks = 0; + desc->data_block_counter = dbc; + desc->ctx_payload = NULL; + ++desc; + ++(*desc_count); + } } else if (s->flags & CIP_JUMBO_PAYLOAD) { // OXFW970 skips transmission for several isoc cycles during - // asynchronous transaction. + // asynchronous transaction. The sequence replay is impossible due + // to the reason. unsigned int safe_cycle = increment_ohci_cycle_count(next_cycle, IR_JUMBO_PAYLOAD_MAX_SKIP_CYCLES); lost = (compare_ohci_cycle_count(safe_cycle, cycle) > 0); @@ -776,6 +792,7 @@ static int generate_device_pkt_descs(struct amdtp_stream *s, dbc = (dbc + desc->data_blocks) & 0xff; next_cycle = increment_ohci_cycle_count(next_cycle, 1); + ++(*desc_count); ctx_header += s->ctx_data.tx.ctx_header_size / sizeof(*ctx_header); packet_index = (packet_index + 1) % queue_size; } @@ -927,6 +944,7 @@ static void in_stream_callback(struct fw_iso_context *context, u32 tstamp, struct amdtp_stream *s = private_data; __be32 *ctx_header = header; unsigned int packets; + unsigned int desc_count; int i; int err; @@ -936,14 +954,15 @@ static void in_stream_callback(struct fw_iso_context *context, u32 tstamp, // Calculate the number of packets in buffer and check XRUN. packets = header_length / s->ctx_data.tx.ctx_header_size; - err = generate_device_pkt_descs(s, s->pkt_descs, ctx_header, packets); + desc_count = 0; + err = generate_device_pkt_descs(s, s->pkt_descs, ctx_header, packets, &desc_count); if (err < 0) { if (err != -EAGAIN) { cancel_stream(s); return; } } else { - process_ctx_payloads(s, s->pkt_descs, packets); + process_ctx_payloads(s, s->pkt_descs, desc_count); } for (i = 0; i < packets; ++i) { |