ALSA: firewire-lib: operate data block counter in top level of processing for IR...

In ALSA IEC 61883-1/6 packet streaming engine, two types of data block
counter are supported. This commit applies code refactoring to make it
explicitly for IR context.

Signed-off-by: Takashi Sakamoto <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 c89083c..3435bef 100644 (file)
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -512,13 +512,14 @@ static void build_it_pkt_header(struct amdtp_stream *s, unsigned int cycle,
 
 static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
                            unsigned int payload_length,
-                           unsigned int *data_blocks, unsigned int *dbc,
-                           unsigned int *syt)
+                           unsigned int *data_blocks,
+                           unsigned int *data_block_counter, unsigned int *syt)
 {
        u32 cip_header[2];
        unsigned int sph;
        unsigned int fmt;
        unsigned int fdf;
+       unsigned int dbc;
        bool lost;
 
        cip_header[0] = be32_to_cpu(buf[0]);
@@ -570,16 +571,16 @@ static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
        }
 
        /* Check data block counter continuity */
-       *dbc = cip_header[0] & CIP_DBC_MASK;
+       dbc = cip_header[0] & CIP_DBC_MASK;
        if (*data_blocks == 0 && (s->flags & CIP_EMPTY_HAS_WRONG_DBC) &&
-           s->data_block_counter != UINT_MAX)
-               *dbc = s->data_block_counter;
+           *data_block_counter != UINT_MAX)
+               dbc = *data_block_counter;
 
-       if ((*dbc == 0x00 && (s->flags & CIP_SKIP_DBC_ZERO_CHECK)) ||
-           s->data_block_counter == UINT_MAX) {
+       if ((dbc == 0x00 && (s->flags & CIP_SKIP_DBC_ZERO_CHECK)) ||
+           *data_block_counter == UINT_MAX) {
                lost = false;
        } else if (!(s->flags & CIP_DBC_IS_END_EVENT)) {
-               lost = *dbc != s->data_block_counter;
+               lost = dbc != *data_block_counter;
        } else {
                unsigned int dbc_interval;
 
@@ -588,13 +589,13 @@ static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
                else
                        dbc_interval = *data_blocks;
 
-               lost = *dbc != ((s->data_block_counter + dbc_interval) & 0xff);
+               lost = dbc != ((*data_block_counter + dbc_interval) & 0xff);
        }
 
        if (lost) {
                dev_err(&s->unit->device,
                        "Detect discontinuity of CIP: %02X %02X\n",
-                       s->data_block_counter, *dbc);
+                       *data_block_counter, dbc);
                return -EIO;
        }
 
@@ -606,10 +607,10 @@ static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
 static int parse_ir_ctx_header(struct amdtp_stream *s, unsigned int cycle,
                               const __be32 *ctx_header,
                               unsigned int *payload_length,
-                              unsigned int *data_blocks, unsigned int *syt,
-                              unsigned int index)
+                              unsigned int *data_blocks,
+                              unsigned int *data_block_counter,
+                              unsigned int *syt, unsigned int index)
 {
-       unsigned int dbc;
        const __be32 *cip_header;
        int err;
 
@@ -625,7 +626,7 @@ static int parse_ir_ctx_header(struct amdtp_stream *s, unsigned int cycle,
        if (!(s->flags & CIP_NO_HEADER)) {
                cip_header = ctx_header + 2;
                err = check_cip_header(s, cip_header, *payload_length,
-                                      data_blocks, &dbc, syt);
+                                      data_blocks, data_block_counter, syt);
                if (err < 0)
                        return err;
        } else {
@@ -635,16 +636,12 @@ static int parse_ir_ctx_header(struct amdtp_stream *s, unsigned int cycle,
                               s->data_block_quadlets;
                *syt = 0;
 
-               if (s->data_block_counter != UINT_MAX)
-                       dbc = s->data_block_counter;
-               else
-                       dbc = 0;
+               if (*data_block_counter == UINT_MAX)
+                       *data_block_counter = 0;
        }
 
-       s->data_block_counter = dbc;
-
        trace_amdtp_packet(s, cycle, cip_header, *payload_length, *data_blocks,
-                          s->data_block_counter, index);
+                          *data_block_counter, index);
 
        return err;
 }
@@ -761,6 +758,7 @@ static void in_stream_callback(struct fw_iso_context *context, u32 tstamp,
                u32 cycle;
                unsigned int payload_length;
                unsigned int data_blocks;
+               unsigned int dbc;
                unsigned int syt;
                __be32 *buffer;
                unsigned int pcm_frames = 0;
@@ -769,22 +767,23 @@ static void in_stream_callback(struct fw_iso_context *context, u32 tstamp,
                int err;
 
                cycle = compute_cycle_count(ctx_header[1]);
+               dbc = s->data_block_counter;
                err = parse_ir_ctx_header(s, cycle, ctx_header, &payload_length,
-                                         &data_blocks, &syt, i);
+                                         &data_blocks, &dbc, &syt, i);
                if (err < 0 && err != -EAGAIN)
                        break;
 
                if (err >= 0) {
                        buffer = s->buffer.packets[s->packet_index].buffer;
                        pcm_frames = s->process_data_blocks(s, buffer,
-                               data_blocks, s->data_block_counter, &syt);
+                               data_blocks, dbc, &syt);
 
-                       if (!(s->flags & CIP_DBC_IS_END_EVENT)) {
-                               s->data_block_counter += data_blocks;
-                               s->data_block_counter &= 0xff;
-                       }
+                       if (!(s->flags & CIP_DBC_IS_END_EVENT))
+                               dbc = (dbc + data_blocks) & 0xff;
                }
 
+               s->data_block_counter = dbc;
+
                if (queue_in_packet(s, &params) < 0)
                        break;