In IEC 61883-6, several types of data are available in AM824 format. The
data is transferred in each data channel. The position of data channel in
data block differs depending on model.

Current implementation has an array to map the index of data channel in an
data block to the position of actual data channel. The implementation
allows each driver to access the mapping directly.

In later commit, the mapping is in specific structure pushed into an
opaque pointer. Helper functions are required.

This commit adds the helper functions for this purpose. In IEC 61883-6,
AM824 format supports many data types, while this specification easily
causes over-engineering. Current AM824 implementation is allowed to handle
two types of data, Multi Bit Linear Audio data (=PCM samples) and MIDI
conformant data (=MIDI messages).
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The value of FDF field in CIP header is protocol-dependent. Thus, it's
better to allow data block processing layer to decide the value in any
timing.

In AM824 data format, the value of FDF field in CIP header indicates
N-flag and Nominal Sampling Frequency Code (sfc). The N-flag is for
switching 'Clock-based rate control mode' and 'Command-based rate control
mode'. In our implementation, 'Clock-based rate control mode' is just
supported. Therefore, When sampling transfer frequency is decided, then
the FDF can be set.

This commit replaces 'amdtp_stream_set_parameters' with
'amdtp_am824_set_parameters' to set the FDF. This is the same timing
to decide the ration between the number of data blocks and the number of
PCM frames.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This commit adds data block processing layer for AM824 format. The new
layer initializes streaming layer with its value for fmt field.

Currently, most implementation of data block processing still remains
streaming layer. In later commits, these codes will be moved to the layer.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

In IEC 61883-6, one data block represents one event. In ALSA, the event is
one PCM frame. Therefore, when processing one data block, current
implementation counts one PCM frame.

On the other hand, Dice platform has a quirk called as 'dual wire' at
higher sampling rate. In detail, see comment of commit 6eb6c81e
("ALSA: dice: Split stream functionality into a file").

Currently, to handle this quirk, AMDTP stream structure has a
'double_pcm_frames' member. When this is enabled, two PCM frames are
counted. Each driver set this flag by accessing the structure member
directly.

In future commit, some members related to AM824 data block will be moved
to specific structure, to separate packet streaming layer and data block
processing layer. The access will be limited by opaque pointer.

For this reason, this commit adds an argument into
amdtp_stream_set_parameter() to set the flag.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Currently, amdtp_stream_set_parameters() returns no error even if wrong
arguments are given. This is not good for streaming layer because drivers
can continue processing ignoring capability of streaming layer.

This commit changes this function to return error code.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Currently stream destructor in each driver has a problem to be called in
a context in which sound card object is released, because the destructors
call amdtp_stream_pcm_abort() and touch PCM runtime data.

The PCM runtime data is destroyed in application's context with
snd_pcm_close(), on the other hand PCM substream data is destroyed after
sound card object is released, in most case after all of ALSA character
devices are released. When PCM runtime is destroyed and PCM substream is
remained, amdtp_stream_pcm_abort() touches PCM runtime data and causes
Null-pointer-dereference.

This commit changes stream destructors and allows each driver to call
it after releasing runtime.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: <stable@vger.kernel.org> # 3.19+
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This commit adds a support for MIDI capture/playback

When MIDI substrams already start streaming and PCM substreams are going to
join at different sampling rate, streams are stopped once. Then sampling rate
is changed and streams are restarted.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: NClemens Ladisch <clemens@ladisch.de>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This commit allows this driver to handle devices with non SYT-Match
sampling clock source.

When sampling clock source is SYT-Match mode, devices handle
'presentation timestamp' in received packets and generates sampling clock
according to the information. In this case, driver is synchronization master
and must transfer correct value in SYT field of each packets in outgoing
stream, then the outgoing stream is a master stream.

On the other hand, non SYT-Match mode, devices do this. So drivers must pick
up the value in SYT field of incoming packets and use the value for outgoing
stream. Currently firewire-lib module achieve this work.

Furthermore, without SYT-Match and internal clock source, the sampling rate
should be fixed for the other devices connected to the handled device. This
commit add a restriction of sampling rate at this situation.

With these implementations, this driver has no need to set clock source.
This commit remove set function.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: NClemens Ladisch <clemens@ladisch.de>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This commit adds support for AMDTP in-stream. As a result, Dice driver
supports full duplex streams with synchronization.

AMDTP can transfer timestamps in its packets. By handling the timestamp,
devices can synchronize to the other devices or drivers on the same bus.

When Dice chipset is 'enabled', it starts streams with correct settings.
This 'enable' register is global, thus, when a stream is started to run,
an opposite stream can't start unless turning off 'enable'. Therefore
a pair of streams must be running. This causes a loss of CPU usage when
single stream is needed for neither playbacking or capturing.

This commit assumes that playback-only models also have a functionality
to transmit stream for delivering timestamps.

Currently, sampling clock source is restricted to SYT-Match mode. This is
improved in followed commit. I note that at SYT-Match mode, Dice can select
from 4 streams for synchronization but this driver uses the 1st stream only
for simplicity.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: NClemens Ladisch <clemens@ladisch.de>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Streaming functionality can start streams when rate is given but currently
some codes are in PCM functionality.

This commit changes the way to start stream and add some arrangement
to make it easy to understand the way.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: NClemens Ladisch <clemens@ladisch.de>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This commit adds a file and move some codes related to PCM functionality.

Currently PCM playback is supported. PCM capture will be supported in followed
commits.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This commit adds a file with some helper functions for streaming, and move some
codes into the file with some arrangements.

Well-known CMP is not used to start/stop streams for Dice chipset. It's
achieved by writing to specific address. We call this way as 'enable'.
When devices are 'enabled', streaming starts in registered isochronous channel.
Some helper functions are already implemented in previous commit.

Basically, the stream is compliant to IEC 61883-6, so-called as AMDTP. But Dice
has a specific quirk, so called-as 'Dual Wire'. This quirk is applied at
176.4/192.0kHz. In this mode, each packet includes double number of events than
number in the specification, and stream runs at a half of sampling rate.

There is another quirk at bus reset. Dice chipset handles drivers' request but
don't re-enable streaming. So stream should be stopped.
Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>