ALSA: firewire-lib: move parameter for pcm frame multiplier from context payload processing layer

The current implementation delegates the task to calculate the number of
processed PCM frames into the context payload processing layer. It looks
good as long as frame calculation is done for a single purpose.
Nevertheless, another purpose, the computation of extra delay for the
runtime of PCM substream, requires frame calculation, too.

This commit refactors the current implementation so that the packet stream
processing layer is responsible for the calculation of PCM frame, too. The
member is moved to stream structure for multiplier between data block
count and PCM frame count.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230110134933.322794-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 16 insertions, 18 deletions

diff --git a/sound/firewire/amdtp-am824.c b/sound/firewire/amdtp-am824.c
index cf55f7784d23..b849f529fcba 100644
--- a/sound/firewire/amdtp-am824.c
+++ b/sound/firewire/amdtp-am824.c
@@ -36,8 +36,6 @@ struct amdtp_am824 {
 
 	u8 pcm_positions[AM824_MAX_CHANNELS_FOR_PCM];
 	u8 midi_position;
-
-	unsigned int frame_multiplier;
 };
 
 /**
@@ -59,8 +57,8 @@ int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate,
 {
 	struct amdtp_am824 *p = s->protocol;
 	unsigned int midi_channels;
-	unsigned int i;
-	int err;
+	unsigned int pcm_frame_multiplier;
+	int i, err;
 
 	if (amdtp_stream_running(s))
 		return -EINVAL;
@@ -77,8 +75,18 @@ int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate,
 	    WARN_ON(midi_channels > AM824_MAX_CHANNELS_FOR_MIDI))
 		return -EINVAL;
 
-	err = amdtp_stream_set_parameters(s, rate,
-					  pcm_channels + midi_channels);
+	/*
+	 * In IEC 61883-6, one data block represents one event. In ALSA, one
+	 * event equals to one PCM frame. But Dice has a quirk at higher
+	 * sampling rate to transfer two PCM frames in one data block.
+	 */
+	if (double_pcm_frames)
+		pcm_frame_multiplier = 2;
+	else
+		pcm_frame_multiplier = 1;
+
+	err = amdtp_stream_set_parameters(s, rate, pcm_channels + midi_channels,
+					  pcm_frame_multiplier);
 	if (err < 0)
 		return err;
 
@@ -88,16 +96,6 @@ int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate,
 	p->pcm_channels = pcm_channels;
 	p->midi_ports = midi_ports;
 
-	/*
-	 * In IEC 61883-6, one data block represents one event. In ALSA, one
-	 * event equals to one PCM frame. But Dice has a quirk at higher
-	 * sampling rate to transfer two PCM frames in one data block.
-	 */
-	if (double_pcm_frames)
-		p->frame_multiplier = 2;
-	else
-		p->frame_multiplier = 1;
-
 	/* init the position map for PCM and MIDI channels */
 	for (i = 0; i < pcm_channels; i++)
 		p->pcm_positions[i] = i;
@@ -361,7 +359,7 @@ static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
 
 		if (pcm) {
 			write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
-			pcm_frames += data_blocks * p->frame_multiplier;
+			pcm_frames += data_blocks * s->pcm_frame_multiplier;
 		} else {
 			write_pcm_silence(s, buf, data_blocks);
 		}
@@ -392,7 +390,7 @@ static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
 
 		if (pcm) {
 			read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
-			pcm_frames += data_blocks * p->frame_multiplier;
+			pcm_frames += data_blocks * s->pcm_frame_multiplier;
 		}
 
 		if (p->midi_ports) {