This commit copies some functions of asynchronous transactions for MIDI capture, to merge scs1x module. The features of payload in asynchronous transaction are:
* System exclusive messages for SCS.1 are encoded without ID data. In this encoding scheme, 4 bits in LSB are available. The bits are squashed in payload byte. Thus, one payload byte transfers two MIDI messages. * The first byte of payload byte means: * 0x00: depending on second payload byte * 0xf9: including escaped system exclusive messages for SCS.1, up to 3 byte (= 6 MIDI messages) * the others: including MIDI 1.0 messages * the others: including escaped system exclusive messages for SCS.1, up to 64 bytes
Signed-off-by: Takashi Sakamoto o-takashi@sakamocchi.jp --- sound/firewire/oxfw/oxfw-scs1x.c | 83 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 82 insertions(+), 1 deletion(-)
diff --git a/sound/firewire/oxfw/oxfw-scs1x.c b/sound/firewire/oxfw/oxfw-scs1x.c index 4a2a7ff..4060bf0 100644 --- a/sound/firewire/oxfw/oxfw-scs1x.c +++ b/sound/firewire/oxfw/oxfw-scs1x.c @@ -11,18 +11,99 @@
#define HSS1394_ADDRESS 0xc007dedadadaULL #define HSS1394_MAX_PACKET_SIZE 64 +#define HSS1394_TAG_USER_DATA 0x00 #define HSS1394_TAG_CHANGE_ADDRESS 0xf1
struct fw_scs1x { struct fw_address_handler hss_handler; + u8 input_escape_count; + struct snd_rawmidi_substream *input; };
+static const u8 sysex_escape_prefix[] = { + 0xf0, /* SysEx begin */ + 0x00, 0x01, 0x60, /* Stanton DJ */ + 0x48, 0x53, 0x53, /* "HSS" */ +}; + +static void midi_input_escaped_byte(struct snd_rawmidi_substream *stream, + u8 byte) +{ + u8 nibbles[2]; + + nibbles[0] = byte >> 4; + nibbles[1] = byte & 0x0f; + snd_rawmidi_receive(stream, nibbles, 2); +} + +static void midi_input_byte(struct fw_scs1x *scs, + struct snd_rawmidi_substream *stream, u8 byte) +{ + const u8 eox = 0xf7; + + if (scs->input_escape_count > 0) { + midi_input_escaped_byte(stream, byte); + scs->input_escape_count--; + if (scs->input_escape_count == 0) + snd_rawmidi_receive(stream, &eox, sizeof(eox)); + } else if (byte == 0xf9) { + snd_rawmidi_receive(stream, sysex_escape_prefix, + ARRAY_SIZE(sysex_escape_prefix)); + midi_input_escaped_byte(stream, 0x00); + midi_input_escaped_byte(stream, 0xf9); + scs->input_escape_count = 3; + } else { + snd_rawmidi_receive(stream, &byte, 1); + } +} + +static void midi_input_packet(struct fw_scs1x *scs, + struct snd_rawmidi_substream *stream, + const u8 *data, unsigned int bytes) +{ + unsigned int i; + const u8 eox = 0xf7; + + if (data[0] == HSS1394_TAG_USER_DATA) { + for (i = 1; i < bytes; ++i) + midi_input_byte(scs, stream, data[i]); + } else { + snd_rawmidi_receive(stream, sysex_escape_prefix, + ARRAY_SIZE(sysex_escape_prefix)); + for (i = 0; i < bytes; ++i) + midi_input_escaped_byte(stream, data[i]); + snd_rawmidi_receive(stream, &eox, sizeof(eox)); + } +} + static void handle_hss(struct fw_card *card, struct fw_request *request, int tcode, int destination, int source, int generation, unsigned long long offset, void *data, size_t length, void *callback_data) { - fw_send_response(card, request, RCODE_COMPLETE); + struct fw_scs1x *scs = callback_data; + struct snd_rawmidi_substream *stream; + int rcode; + + if (offset != scs->hss_handler.offset) { + rcode = RCODE_ADDRESS_ERROR; + goto end; + } + if (tcode != TCODE_WRITE_QUADLET_REQUEST && + tcode != TCODE_WRITE_BLOCK_REQUEST) { + rcode = RCODE_TYPE_ERROR; + goto end; + } + + if (length >= 1) { + stream = ACCESS_ONCE(scs->input); + if (stream) + midi_input_packet(scs, stream, data, length); + } + + rcode = RCODE_COMPLETE; +end: + fw_send_response(card, request, rcode); }
static int register_address(struct snd_oxfw *oxfw)