ALSA: fireface: add helper function to parse MIDI messages transmitted by Fireface 400

[linux-2.6-microblaze.git] / sound / firewire / fireface / ff-protocol-former.c

diff --git a/sound/firewire/fireface/ff-protocol-former.c b/sound/firewire/fireface/ff-protocol-former.c
index 22d6aee..d2cc996 100644 (file)
--- a/sound/firewire/fireface/ff-protocol-former.c
+++ b/sound/firewire/fireface/ff-protocol-former.c
@@ -534,6 +534,22 @@ static void ff400_finish_session(struct snd_ff *ff)
                           FF400_ISOC_COMM_STOP, &reg, sizeof(reg), 0);
 }
 
+static void parse_midi_msg(struct snd_ff *ff, u32 quad, unsigned int port)
+{
+       struct snd_rawmidi_substream *substream = READ_ONCE(ff->tx_midi_substreams[port]);
+
+       if (substream != NULL) {
+               u8 byte = (quad >> (16 * port)) & 0x000000ff;
+
+               snd_rawmidi_receive(substream, &byte, 1);
+       }
+}
+
+#define FF400_MSG_FLAG_IS_MIDI_PORT_0          0x00000100
+#define  FF400_MSG_MASK_MIDI_PORT_0            0x000000ff
+#define FF400_MSG_FLAG_IS_MIDI_PORT_1          0x01000000
+#define  FF400_MSG_MASK_MIDI_PORT_1            0x00ff0000
+
 // For Fireface 400, lower 4 bytes of destination address is configured by bit
 // flag in quadlet register (little endian) at 0x'0000'801'0051c. Drivers can
 // select one of 4 options:
@@ -560,34 +576,11 @@ static void ff400_handle_msg(struct snd_ff *ff, unsigned int offset, const __le3
 
        for (i = 0; i < length / 4; i++) {
                u32 quad = le32_to_cpu(buf[i]);
-               u8 byte;
-               unsigned int index;
-               struct snd_rawmidi_substream *substream;
 
-               /* Message in first port. */
-               /*
-                * This value may represent the index of this unit when the same
-                * units are on the same IEEE 1394 bus. This driver doesn't use
-                * it.
-                */
-               index = (quad >> 8) & 0xff;
-               if (index > 0) {
-                       substream = READ_ONCE(ff->tx_midi_substreams[0]);
-                       if (substream != NULL) {
-                               byte = quad & 0xff;
-                               snd_rawmidi_receive(substream, &byte, 1);
-                       }
-               }
-
-               /* Message in second port. */
-               index = (quad >> 24) & 0xff;
-               if (index > 0) {
-                       substream = READ_ONCE(ff->tx_midi_substreams[1]);
-                       if (substream != NULL) {
-                               byte = (quad >> 16) & 0xff;
-                               snd_rawmidi_receive(substream, &byte, 1);
-                       }
-               }
+               if (quad & FF400_MSG_FLAG_IS_MIDI_PORT_0)
+                       parse_midi_msg(ff, quad, 0);
+               else if (quad & FF400_MSG_FLAG_IS_MIDI_PORT_1)
+                       parse_midi_msg(ff, quad, 1);
        }
 }