TASCAM FE-8 is the rest of model in TASCAM FireWire series. This device
has no functionality to process audio signal and MIDI messages. Instead,
it transfers control messages to host system corresponding to operations
for some faders, buttons and knobs on its surface.
Unlike the other devices in this series, the control messages are
transmitted by asynchronous transactions. Some registers of device are
used for registration of destination address for the transaction. The
transaction includes quadlet-aligned data up to 32 quadlets.
Userspace applications can receive the transaction and parse it for
control message via Linux FireWire subsystem, without any support by
ALSA firewire-tascam driver. Therefore the driver gives no support
for it.
This commit removes placeholder for FE-8 and add some comment for its
functionalities as notes.
$ python2 linux-firewire-utils/src/crpp < ~/git/am-config-rom/tascam/tascam-fe8.img
ROM header and bus information block
-----------------------------------------------------------------
400 040f4798 bus_info_length 4, crc_length 15, crc 18328 (should be 14256)
404 31333934 bus_name "1394"
408 20ff7002 irmc 0, cmc 0, isc 1, bmc 0, cyc_clk_acc 255, max_rec 7 (256)
40c 00022eff company_id 00022e |
410 a094dcb7 device_id ffa094dcb7 | EUI-64 00022effa094dcb7
root directory
-----------------------------------------------------------------
414 0004bccc directory_length 4, crc 48332
418 0300022e vendor
41c 0c0083c0 node capabilities per IEEE 1394
420 8d000006 --> eui-64 leaf at 438
424 d1000001 --> unit directory at 428
unit directory at 428
-----------------------------------------------------------------
428 0003eda4 directory_length 3, crc 60836
42c 1200022e specifier id
430 13800001 version
434 d4000004 --> dependent info directory at 444
eui-64 leaf at 438
-----------------------------------------------------------------
438 0002461e leaf_length 2, crc 17950
43c 00022eff company_id 00022e |
440 a094dcb7 device_id ffa094dcb7 | EUI-64 00022effa094dcb7
dependent info directory at 444
-----------------------------------------------------------------
444 0002ae47 directory_length 2, crc 44615
448 81000002 --> descriptor leaf at 450
44c 82000006 --> bus dependent info leaf at 464
descriptor leaf at 450
-----------------------------------------------------------------
450 0004a79e leaf_length 4, crc 42910
454 00000000 textual descriptor
458 00000000 minimal ASCII
45c 54415343 "TASC"
460 414d0000 "AM"
bus dependent info leaf at 464
-----------------------------------------------------------------
464 0004a7d8 leaf_length 4, crc 42968
468 00000000
46c 00000000
470 46452d38
474 00000000
Signed-off-by: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx>
---
sound/firewire/tascam/tascam.c | 4 +++-
sound/firewire/tascam/tascam.h | 20 ++++++++++++++++++++
2 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/sound/firewire/tascam/tascam.c b/sound/firewire/tascam/tascam.c
index 231052db5680..addc464503bc 100644
--- a/sound/firewire/tascam/tascam.c
+++ b/sound/firewire/tascam/tascam.c
@@ -39,6 +39,9 @@ static const struct snd_tscm_spec model_specs[] = {
.midi_capture_ports = 2,
.midi_playback_ports = 4,
},
+ // This kernel module doesn't support FE-8 because the most of features
+ // can be implemented in userspace without any specific support of this
+ // module.
};
static int identify_model(struct snd_tscm *tscm)
@@ -214,7 +217,6 @@ static const struct ieee1394_device_id snd_tscm_id_table[] = {
.vendor_id = 0x00022e,
.specifier_id = 0x00022e,
},
- /* FE-08 requires reverse-engineering because it just has faders. */
{}
};
MODULE_DEVICE_TABLE(ieee1394, snd_tscm_id_table);
diff --git a/sound/firewire/tascam/tascam.h b/sound/firewire/tascam/tascam.h
index 64a2e4d2bbfe..15bd335fa07f 100644
--- a/sound/firewire/tascam/tascam.h
+++ b/sound/firewire/tascam/tascam.h
@@ -129,6 +129,26 @@ struct snd_tscm {
#define TSCM_OFFSET_MIDI_RX_QUAD 0x4000
+// Although FE-8 supports the above registers, it has no I/O interfaces for
+// audio samples and music messages. Otherwise it supports another notification
+// for status and control message as well as LED brightening. The message
+// consists of quadlet-aligned data up to 32 quadlets. The first byte of message
+// is fixed to 0x40. The second byte is between 0x00 to 0x1f and represent each
+// control:
+// fader: 0x00-0x07
+// button: 0x0d, 0x0e
+// knob: 0x14-0x1b
+// sensing: 0x0b
+//
+// The rest two bytes represent state of the controls; e.g. current value for
+// fader and knob, bitmasks for button and sensing.
+// Just after turning on, 32 quadlets messages with 0x00-0x1f are immediately
+// sent in one transaction. After, several quadlets are sent in one transaction.
+//
+// TSCM_OFFSET_FE8_CTL_TX_ON 0x0310
+// TSCM_OFFSET_FE8_CTL_TX_ADDR_HI 0x0314
+// TSCM_OFFSET_FE8_CTL_TX_ADDR_LO 0x0318
+
enum snd_tscm_clock {
SND_TSCM_CLOCK_INTERNAL = 0,
SND_TSCM_CLOCK_WORD = 1,
--
2.20.1
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