1 files changed, 23 insertions, 7 deletions

diff --git a/sound/firewire/amdtp.c b/sound/firewire/amdtp.c
index 16fe858925bd..38013f918869 100644
--- a/sound/firewire/amdtp.c
+++ b/sound/firewire/amdtp.c
@@ -20,12 +20,28 @@
 
 #define TRANSFER_DELAY_TICKS    0x2e00 /* 479.17 µs */
 
+/* isochronous header parameters */
+#define ISO_DATA_LENGTH_SHIFT   16
 #define TAG_CIP                 1
 
+/* common isochronous packet header parameters */
 #define CIP_EOH                 (1u << 31)
+#define CIP_EOH_MASK            0x80000000
 #define CIP_FMT_AM              (0x10 << 24)
-#define AMDTP_FDF_AM824         (0 << 19)
-#define AMDTP_FDF_SFC_SHIFT     16
+#define CIP_FMT_MASK            0x3f000000
+#define CIP_SYT_MASK            0x0000ffff
+#define CIP_SYT_NO_INFO         0xffff
+#define CIP_FDF_MASK            0x00ff0000
+#define CIP_FDF_SFC_SHIFT       16
+
+/*
+ * Audio and Music transfer protocol specific parameters
+ * only "Clock-based rate control mode" is supported
+ */
+#define AMDTP_FDF_AM824         (0 << (CIP_FDF_SFC_SHIFT + 3))
+#define AMDTP_DBS_MASK          0x00ff0000
+#define AMDTP_DBS_SHIFT         16
+#define AMDTP_DBC_MASK          0x000000ff
 
 /* TODO: make these configurable */
 #define INTERRUPT_INTERVAL      16
@@ -280,9 +296,9 @@ static unsigned int calculate_syt(struct amdtp_stream *s,
                 syt = (cycle + syt_offset / TICKS_PER_CYCLE) << 12;
                 syt += syt_offset % TICKS_PER_CYCLE;
 
-                return syt & 0xffff;
+                return syt & CIP_SYT_MASK;
         } else {
-                return 0xffff; /* no info */
+                return CIP_SYT_NO_INFO;
         }
 }
 
@@ -438,17 +454,17 @@ static void queue_out_packet(struct amdtp_stream *s, unsigned int cycle)
         syt = calculate_syt(s, cycle);
         if (!(s->flags & CIP_BLOCKING))
                 data_blocks = calculate_data_blocks(s);
-        else if (syt != 0xffff)
+        else if (syt != CIP_SYT_NO_INFO)
                 data_blocks = s->syt_interval;
         else
                 data_blocks = 0;
 
         buffer = s->buffer.packets[index].buffer;
         buffer[0] = cpu_to_be32(ACCESS_ONCE(s->source_node_id_field) |
-                                (s->data_block_quadlets << 16) |
+                                (s->data_block_quadlets << AMDTP_DBS_SHIFT) |
                                 s->data_block_counter);
         buffer[1] = cpu_to_be32(CIP_EOH | CIP_FMT_AM | AMDTP_FDF_AM824 |
-                                (s->sfc << AMDTP_FDF_SFC_SHIFT) | syt);
+                                (s->sfc << CIP_FDF_SFC_SHIFT) | syt);
         buffer += 2;
 
         pcm = ACCESS_ONCE(s->pcm);