ALSA: firewire-lib: obsolete return value from context payload processing layer

This commit obsoletes return value from the context payload processing layer
since the multiplier between the data block count and PCM frame count was
moved to the packet streaming processing layer.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230110134933.322794-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: firewire-lib: move parameter for pcm frame multiplier from context payload processing layer

The current implementation delegates the task to calculate the number of
processed PCM frames into the context payload processing layer. It looks
good as long as frame calculation is done for a single purpose.
Nevertheless, another purpose, the computation of extra delay for the
runtime of PCM substream, requires frame calculation, too.

This commit refactors the current implementation so that the packet stream
processing layer is responsible for the calculation of PCM frame, too. The
member is moved to stream structure for multiplier between data block
count and PCM frame count.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230110134933.322794-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: firewire-lib: use circular linked list for context payload processing layer

The list of packet descriptor is passed to context payload processing
layer so that each driver can copy PCM frames, MIDI messages, and device
specific data between packet payload buffer and intermediate buffer for
user space application.

The list of packet descriptor was replaced by circular linked list in a
previous commit. This commit uses circular linked in context payload
processing layer as well.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230109021738.75543-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: fireface: perform sequence replay for media clock recovery

This commit takes ALSA fireface driver to perform sequence replay for
media clock recovery.

The protocol specific to RME Fireface series is not compliant to
IEC 61883-1/6 since it has no CIP header, therefore presentation time
is not used for media clock recovery. The sequence of the number of data
blocks per packet is important.

I note that the device skips an isochronous cycle corresponding to an
empty packet or a NODATA packet in blocking transmission method of
IEC 61883-1/6. For sequence replay, the cycle is handled as receiving an
empty packet. Furthermore, it doesn't start packet transmission till
receiving any packet.

The sequence replay is tested with below models:

* Fireface 400
* Fireface 800
* Fireface 802

I note that it is better to initialize Fireface 400 in advance by
initialization transaction implemented in snd-fireface-ctl-service of
snd-firewire-ctl-services project. You can see whether initialized or
not by HOST LED on the device. Unless, the device often stops packet
transmission even if session starts.

I guess the sequence replay also works well with below models:

* Fireface UFX
* Fireface UCX

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210531025103.17880-7-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: firewire-lib: process payload of isoc context according to packet descriptors

This commit changes each of data block processing layer so that it
receives list of packet descriptor.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: fireface: code refactoring for FF data block processing layer

This is code refactoring for FF data block processing layer so that
it can receive list of packet descriptor.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: firewire-lib: pass packet descriptor to data block processing layer

This commit changes signature of callback function to call data block
processing layer with packet descriptor. At present, the layer is called
per packet.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: firewire-lib: pass no syt information to data block processing layer

In a previous commit, the variable passed from packet streaming layer
for syt variable is useless. This commit obsoletes it.

In my future work, the syt information is passed to data block processing
layer by another way.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: firewire-lib: pass data block counter to data block processing layer

This is a preparation for future commit that 'struct
amdtp_stream.data_block_count' does not represent the value of
data block count for current data block.

However, data block count is required for calculation of sequence index
in sequence-multiplied data channel. Some of data block processing layer
require it; e.g. for AM824 data block.

This commit passes data block count to the processing layer.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 345

Based on 1 normalized pattern(s):

licensed under the terms of the gnu general public license version 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 88 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000437.521539229@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()

Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

ALSA: fireface: add unique data processing layer

As long as investigating Fireface 400, format of payload of each
isochronous packet is not IEC 61883-1/6, thus its format of data block
is not AM824. The remarkable points of the format are:
* The payload just consists of some data channels of quadlet size without
CIP header.
* Each data channels includes data aligned to little endian order.
* One data channel consists of two parts; 8 bit ancillary field and 24 bit
PCM frame.

Due to lack of CIP headers, rx/tx packets include no CIP headers and
different way to check packet discontinuity. For tx packet, the ancillary
field is used for counter. However, the way of counting is different
depending on positions of data channels. At 44.1 kHz, ancillary field in:
* 1st/6th/9th/10th/14th/17th data channels: not used for this purpose.
* 2nd/18th data channels: incremented every data block (0x00-0xff).
* 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data
blocks (0x00-0x07).
* 7th/8th/15th/16th data channels: incremented per the number of data
blocks in a packet. The increment can occur per packet (0x00-0xff).

For tx packet, tag of each isochronous packet is used for this purpose.
The value of tag cyclically changes between 0, 1, 2 and 3 in this order.
The interval is different depending on sampling transmission frequency.
At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks.

The number of data blocks in tx packet is exactly the same as
SYT_INTERVAL. There's no empty packet or no-data packet, thus the
throughput is not 8,000 packets per sec. On the other hand, the one in
rx packet is 8,000 packets per sec, thus the number of data blocks is
different between each packet, depending on sampling transmission
frequency:
* 44.1 kHz: 5 or 6
* 48.0 kHz: 5 or 6 or 7
* 88.2 kHz: 10 or 11 or 12

This commit adds data processing layer to satisfy the above specification
in a policy of 'best effort'. Although PCM frames are handled for
intermediate buffer to user space, the ancillary data is not handled at all
to reduce CPU usage, thus counter is not checked. 0 is always used for tag
of isochronous packet. Furthermore, the packet streaming layer is
responsible for calculation of the number of data blocks for each packet,
thus it's not exactly the same sequence from the above observation.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>