ALSA: firewire-lib: code refactoring for generation of syt sequence

This commit dissolves sequence generator in terms of syt offsets for
packet.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210522013303.49596-5-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 354512a..77ae75e 100644 (file)
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -441,8 +441,30 @@ static unsigned int calculate_syt_offset(unsigned int *last_syt_offset,
        return syt_offset;
 }
 
+static void pool_ideal_syt_offsets(struct amdtp_stream *s, struct seq_desc *descs,
+                                  const unsigned int seq_size, unsigned int seq_tail,
+                                  unsigned int count)
+{
+       const enum cip_sfc sfc = s->sfc;
+       unsigned int last = s->ctx_data.rx.last_syt_offset;
+       unsigned int state = s->ctx_data.rx.syt_offset_state;
+       int i;
+
+       for (i = 0; i < count; ++i) {
+               struct seq_desc *desc = descs + seq_tail;
+
+               desc->syt_offset = calculate_syt_offset(&last, &state, sfc);
+
+               seq_tail = (seq_tail + 1) % seq_size;
+       }
+
+       s->ctx_data.rx.last_syt_offset = last;
+       s->ctx_data.rx.syt_offset_state = state;
+}
+
 static void pool_ideal_seq_descs(struct amdtp_stream *s, unsigned int count)
 {
+       struct seq_desc *descs = s->ctx_data.rx.seq.descs;
        unsigned int seq_tail = s->ctx_data.rx.seq.tail;
        const unsigned int seq_size = s->ctx_data.rx.seq.size;
        const unsigned int syt_interval = s->syt_interval;
@@ -450,11 +472,11 @@ static void pool_ideal_seq_descs(struct amdtp_stream *s, unsigned int count)
        const bool is_blocking = !!(s->flags & CIP_BLOCKING);
        int i;
 
+       pool_ideal_syt_offsets(s, descs, seq_size, seq_tail, count);
+
        for (i = 0; i < count; ++i) {
                struct seq_desc *desc = s->ctx_data.rx.seq.descs + seq_tail;
 
-               desc->syt_offset = calculate_syt_offset(&s->ctx_data.rx.last_syt_offset,
-                                       &s->ctx_data.rx.syt_offset_state, sfc);
                desc->data_blocks = calculate_data_blocks(&s->ctx_data.rx.data_block_state,
                                is_blocking, desc->syt_offset == CIP_SYT_NO_INFO,
                                syt_interval, sfc);