Commit Graph

5 Commits

Author SHA1 Message Date
Takashi Sakamoto ff2c293efa ALSA: fireface: add support for MIDI functionality
In previous commit, fireface driver supports unique transaction mechanism
for MIDI feature. This commit adds MIDI functionality for userspace
applications.

As I wrote in a followed commit, user space applications get some
requirement from this driver. It should not touch a register to which
units transmit MIDI messages. It should configure a register in which
MIDI transmission is controlled.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-04-05 21:31:34 +02:00
Takashi Sakamoto 1917429578 ALSA: fireface: add transaction support
As long as investigating Fireface 400, MIDI messages are transferred by
asynchronous communication over IEEE 1394 bus.

Fireface 400 receives MIDI messages by write transactions to two addresses;
0x'0000'0801'8000 and 0x'0000'0801'9000. Each of two seems to correspond to
MIDI port 1 and 2.

Fireface 400 transfers MIDI messages by write transactions to certain
addresses which configured by drivers. The drivers can decide upper 4 byte
of the addresses by write transactions to 0x'0000'0801'03f4. For the rest
part of the address, drivers can select from below options:
 * 0x'0000'0000
 * 0x'0000'0080
 * 0x'0000'0100
 * 0x'0000'0180

Selected options are represented in register 0x'0000'0801'051c as bit
flags. Due to this mechanism, drivers are restricted to use addresses on
'Memory space' of IEEE 1222, even if transactions to the address have
some side effects.

This commit adds transaction support for MIDI messaging, based on my
assumption that the similar mechanism is used on the other protocols. To
receive asynchronous transactions, the driver allocates a range of address
in 'Memory space'. I apply a strategy to use 0x'0000'0000 as lower 4 byte
of the address. When getting failure from Linux FireWire subsystem, this
driver retries to allocate addresses.

Unfortunately, read transaction to address 0x'0000'0801'051c returns zero
always, however write transactions have effects to the other features such
as status of sampling clock. For this reason, this commit delegates a task
to configure this register to user space applications. The applications
should set 3rd bit in LSB in little endian order.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-04-05 21:31:31 +02:00
Takashi Sakamoto ed90f91a17 ALSA: fireface: add model specific structure
RME Fireface series has several models and their specifications are
different. Currently, we find no way to retrieve the specifications
from actual devices and need to implement them in this driver.

This commit adds a structure to describe model specific data. This
structure has an identical name for each unit, and maximum number of
data channels in each mode. I'll describe about the mode in following
commits.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-04-05 21:31:28 +02:00
Takashi Sakamoto 324540c4e0 ALSA: fireface: postpone sound card registration
Just after appearing on IEEE 1394 bus, this unit generates several bus
resets. This is due to loading firmware from on-board flash memory and
initialize hardware. It's better to postpone sound card registration.

This commit schedules workqueue to process actual probe processing
2 seconds after the last bus-reset. The card instance is kept at unit
probe callback and released at card free callback. Therefore, when the
actual probe processing fails, the memory block is wasted. This is due to
simplify driver implementation.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-04-05 21:31:26 +02:00
Takashi Sakamoto 17c4e5eadc ALSA: fireface: add skeleton for RME Fireface series
This commit adds a new driver for RME Fireface series. This commit just
creates/removes card instance according to IEEE 1394 bus event. More
functions will be added in following commits.

Three types of firmware have released by RME GmbH; for Fireface 400, for
Fireface 800 and for UCX/802/UFX. It's reasonable that these models use
different protocol for communication. Currently, I've investigated
Fireface 400 and nothing others.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-04-05 21:31:24 +02:00