ALSA: firewire-tascam: code refactoring for TASCAM data block processing layer

[sfrench/cifs-2.6.git] / sound / firewire / tascam / amdtp-tascam.c

diff --git a/sound/firewire/tascam/amdtp-tascam.c b/sound/firewire/tascam/amdtp-tascam.c
index 970b1c4a8ea64c0037e40f43c57849d71d7e393b..3c9abf422f24b915a099353525862687bb67c1f6 100644 (file)
--- a/sound/firewire/tascam/amdtp-tascam.c
+++ b/sound/firewire/tascam/amdtp-tascam.c
@@ -32,19 +32,24 @@ int amdtp_tscm_set_parameters(struct amdtp_stream *s, unsigned int rate)
        return amdtp_stream_set_parameters(s, rate, data_channels);
 }
 
-static void write_pcm_s32(struct amdtp_stream *s,
-                         struct snd_pcm_substream *pcm,
-                         __be32 *buffer, unsigned int frames)
+static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
+                         __be32 *buffer, unsigned int frames,
+                         unsigned int pcm_frames)
 {
        struct amdtp_tscm *p = s->protocol;
+       unsigned int channels = p->pcm_channels;
        struct snd_pcm_runtime *runtime = pcm->runtime;
-       unsigned int channels, remaining_frames, i, c;
+       unsigned int pcm_buffer_pointer;
+       int remaining_frames;
        const u32 *src;
+       int i, c;
+
+       pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
+       pcm_buffer_pointer %= runtime->buffer_size;
 
-       channels = p->pcm_channels;
        src = (void *)runtime->dma_area +
-                       frames_to_bytes(runtime, s->pcm_buffer_pointer);
-       remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
+                               frames_to_bytes(runtime, pcm_buffer_pointer);
+       remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 
        for (i = 0; i < frames; ++i) {
                for (c = 0; c < channels; ++c) {
@@ -57,19 +62,24 @@ static void write_pcm_s32(struct amdtp_stream *s,
        }
 }
 
-static void read_pcm_s32(struct amdtp_stream *s,
-                        struct snd_pcm_substream *pcm,
-                        __be32 *buffer, unsigned int frames)
+static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
+                        __be32 *buffer, unsigned int frames,
+                        unsigned int pcm_frames)
 {
        struct amdtp_tscm *p = s->protocol;
+       unsigned int channels = p->pcm_channels;
        struct snd_pcm_runtime *runtime = pcm->runtime;
-       unsigned int channels, remaining_frames, i, c;
+       unsigned int pcm_buffer_pointer;
+       int remaining_frames;
        u32 *dst;
+       int i, c;
+
+       pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
+       pcm_buffer_pointer %= runtime->buffer_size;
 
-       channels = p->pcm_channels;
        dst  = (void *)runtime->dma_area +
-                       frames_to_bytes(runtime, s->pcm_buffer_pointer);
-       remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer;
+                               frames_to_bytes(runtime, pcm_buffer_pointer);
+       remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
 
        /* The first data channel is for event counter. */
        buffer += 1;
@@ -169,13 +179,12 @@ static unsigned int process_tx_data_blocks(struct amdtp_stream *s,
                                           const struct pkt_desc *desc,
                                           struct snd_pcm_substream *pcm)
 {
-       unsigned int pcm_frames;
+       unsigned int pcm_frames = 0;
 
        if (pcm) {
-               read_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
-               pcm_frames = desc->data_blocks;
-       } else {
-               pcm_frames = 0;
+               read_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks,
+                            pcm_frames);
+               pcm_frames += desc->data_blocks;
        }
 
        read_status_messages(s, desc->ctx_payload, desc->data_blocks);
@@ -187,14 +196,14 @@ static unsigned int process_rx_data_blocks(struct amdtp_stream *s,
                                           const struct pkt_desc *desc,
                                           struct snd_pcm_substream *pcm)
 {
-       unsigned int pcm_frames;
+       unsigned int pcm_frames = 0;
 
        if (pcm) {
-               write_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks);
-               pcm_frames = desc->data_blocks;
+               write_pcm_s32(s, pcm, desc->ctx_payload, desc->data_blocks,
+                             pcm_frames);
+               pcm_frames += desc->data_blocks;
        } else {
                write_pcm_silence(s, desc->ctx_payload, desc->data_blocks);
-               pcm_frames = 0;
        }
 
        return pcm_frames;