ALSA: firewire-lib: keep history to process isochronous packet

The history to process isochronous packets is useful when computing gap
between current isochronous cycle and the latest isochronous cycle in
which packet is processed (in IR context) and scheduled (in IT context).

This commit stores the most recent packet descriptors to keep the history.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230109021738.75543-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index 006dc939065f8049d4938aa00e989b8e6183f5fd..430b33dc60b337353a5cc9fa827b125750bf834e 100644 (file)
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -1047,7 +1047,7 @@ static void process_rx_packets(struct fw_iso_context *context, u32 tstamp, size_
        const __be32 *ctx_header = header;
        const unsigned int events_per_period = d->events_per_period;
        unsigned int event_count = s->ctx_data.rx.event_count;
-       struct pkt_desc *desc = s->pkt_descs;
+       struct pkt_desc *desc = s->packet_descs_cursor;
        unsigned int pkt_header_length;
        unsigned int packets;
        bool need_hw_irq;
@@ -1106,6 +1106,7 @@ static void process_rx_packets(struct fw_iso_context *context, u32 tstamp, size_
        }
 
        s->ctx_data.rx.event_count = event_count;
+       s->packet_descs_cursor = desc;
 }
 
 static void skip_rx_packets(struct fw_iso_context *context, u32 tstamp, size_t header_length,
@@ -1202,7 +1203,7 @@ static void process_tx_packets(struct fw_iso_context *context, u32 tstamp, size_
 {
        struct amdtp_stream *s = private_data;
        __be32 *ctx_header = header;
-       struct pkt_desc *desc = s->pkt_descs;
+       struct pkt_desc *desc = s->packet_descs_cursor;
        unsigned int packet_count;
        unsigned int desc_count;
        int i;
@@ -1228,6 +1229,10 @@ static void process_tx_packets(struct fw_iso_context *context, u32 tstamp, size_
 
                if (d->replay.enable)
                        cache_seq(s, desc, desc_count);
+
+               for (i = 0; i < desc_count; ++i)
+                       desc = amdtp_stream_next_packet_desc(s, desc);
+               s->packet_descs_cursor = desc;
        }
 
        for (i = 0; i < packet_count; ++i) {
@@ -1664,7 +1669,7 @@ static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed,
                err = -ENOMEM;
                goto err_context;
        }
-       s->pkt_descs = descs;
+       s->packet_descs = descs;
 
        INIT_LIST_HEAD(&s->packet_descs_list);
        for (i = 0; i < s->queue_size; ++i) {
@@ -1672,6 +1677,7 @@ static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed,
                list_add_tail(&descs->link, &s->packet_descs_list);
                ++descs;
        }
+       s->packet_descs_cursor = list_first_entry(&s->packet_descs_list, struct pkt_desc, link);
 
        s->packet_index = 0;
        do {
@@ -1710,8 +1716,8 @@ static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed,
 
        return 0;
 err_pkt_descs:
-       kfree(s->pkt_descs);
-       s->pkt_descs = NULL;
+       kfree(s->packet_descs);
+       s->packet_descs = NULL;
 err_context:
        if (s->direction == AMDTP_OUT_STREAM) {
                kfree(s->ctx_data.rx.seq.descs);
@@ -1805,8 +1811,8 @@ static void amdtp_stream_stop(struct amdtp_stream *s)
        fw_iso_context_destroy(s->context);
        s->context = ERR_PTR(-1);
        iso_packets_buffer_destroy(&s->buffer, s->unit);
-       kfree(s->pkt_descs);
-       s->pkt_descs = NULL;
+       kfree(s->packet_descs);
+       s->packet_descs = NULL;
 
        if (s->direction == AMDTP_OUT_STREAM) {
                kfree(s->ctx_data.rx.seq.descs);

diff --git a/sound/firewire/amdtp-stream.h b/sound/firewire/amdtp-stream.h
index 84156d0d57b83ac1d823abd2666444c25f4126ec..a8dd1c3ec8d91b9b46c2403f66f569506f57cc0f 100644 (file)
--- a/sound/firewire/amdtp-stream.h
+++ b/sound/firewire/amdtp-stream.h
@@ -126,8 +126,9 @@ struct amdtp_stream {
        struct iso_packets_buffer buffer;
        unsigned int queue_size;
        int packet_index;
-       struct pkt_desc *pkt_descs;
+       struct pkt_desc *packet_descs;
        struct list_head packet_descs_list;
+       struct pkt_desc *packet_descs_cursor;
        int tag;
        union {
                struct {