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ALSA: firewire-lib: code refactoring for generation of data block sequence

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This commit dissolves sequence generator in terms of the number of data
blocks per packet.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210522013303.49596-6-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Sakamoto 2021-05-22 10:33:02 +09:00 committed by Takashi Iwai
parent c79b7158b0
commit c9f3ac2aae
1 changed files with 40 additions and 33 deletions
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73
sound/firewire/amdtp-stream.c
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@ -357,26 +357,41 @@ void amdtp_stream_pcm_prepare(struct amdtp_stream *s)
}
EXPORT_SYMBOL(amdtp_stream_pcm_prepare);
static unsigned int calculate_data_blocks(unsigned int *data_block_state,
bool is_blocking, bool is_no_info,
unsigned int syt_interval, enum cip_sfc sfc)
static void pool_blocking_data_blocks(struct amdtp_stream *s, struct seq_desc *descs,
const unsigned int seq_size, unsigned int seq_tail,
unsigned int count)
{
unsigned int data_blocks;
const unsigned int syt_interval = s->syt_interval;
int i;
/* Blocking mode. */
if (is_blocking) {
/* This module generate empty packet for 'no data'. */
if (is_no_info)
data_blocks = 0;
for (i = 0; i < count; ++i) {
struct seq_desc *desc = descs + seq_tail;
if (desc->syt_offset != CIP_SYT_NO_INFO)
desc->data_blocks = syt_interval;
else
data_blocks = syt_interval;
/* Non-blocking mode. */
} else {
desc->data_blocks = 0;
seq_tail = (seq_tail + 1) % seq_size;
}
}
static void pool_ideal_nonblocking_data_blocks(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 state = s->ctx_data.rx.data_block_state;
int i;
for (i = 0; i < count; ++i) {
struct seq_desc *desc = descs + seq_tail;
if (!cip_sfc_is_base_44100(sfc)) {
// Sample_rate / 8000 is an integer, and precomputed.
data_blocks = *data_block_state;
desc->data_blocks = state;
} else {
unsigned int phase = *data_block_state;
unsigned int phase = state;
/*
* This calculates the number of data blocks per packet so that
@ -388,18 +403,19 @@ static unsigned int calculate_data_blocks(unsigned int *data_block_state,
*/
if (sfc == CIP_SFC_44100)
/* 6 6 5 6 5 6 5 ... */
data_blocks = 5 + ((phase & 1) ^
(phase == 0 || phase >= 40));
desc->data_blocks = 5 + ((phase & 1) ^ (phase == 0 || phase >= 40));
else
/* 12 11 11 11 11 ... or 23 22 22 22 22 ... */
data_blocks = 11 * (sfc >> 1) + (phase == 0);
desc->data_blocks = 11 * (sfc >> 1) + (phase == 0);
if (++phase >= (80 >> (sfc >> 1)))
phase = 0;
*data_block_state = phase;
state = phase;
}
seq_tail = (seq_tail + 1) % seq_size;
}
return data_blocks;
s->ctx_data.rx.data_block_state = state;
}
static unsigned int calculate_syt_offset(unsigned int *last_syt_offset,
@ -467,24 +483,15 @@ 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;
const enum cip_sfc sfc = s->sfc;
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;
if (s->flags & CIP_BLOCKING)
pool_blocking_data_blocks(s, descs, seq_size, seq_tail, count);
else
pool_ideal_nonblocking_data_blocks(s, descs, seq_size, seq_tail, count);
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);
seq_tail = (seq_tail + 1) % seq_size;
}
s->ctx_data.rx.seq.tail = seq_tail;
s->ctx_data.rx.seq.tail = (seq_tail + count) % seq_size;
}
static void update_pcm_pointers(struct amdtp_stream *s,