firewire: core: update documentation of kernel APIs for flushing completions

There is a slight difference between fw_iso_context_flush_completions() and
fw_iso_context_schedule_flush_completions().

firewire: core: update documentation of kernel APIs for flushing completions

There is a slight difference between fw_iso_context_flush_completions() and
fw_iso_context_schedule_flush_completions().

This commit updates the documentations for them.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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Revert "firewire: core: use mutex to coordinate concurrent calls to flush completions"

This reverts commit d9605d67562505e27dcc0f71af418118d3db91e5, since this
commit is on the following reverted ch

Revert "firewire: core: use mutex to coordinate concurrent calls to flush completions"

This reverts commit d9605d67562505e27dcc0f71af418118d3db91e5, since this
commit is on the following reverted changes.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: core: use mutex to coordinate concurrent calls to flush completions

In current implementation, test_and_set_bit_lock() is used to mediate
concurrent calls of ohci_flush_iso_completions().

firewire: core: use mutex to coordinate concurrent calls to flush completions

In current implementation, test_and_set_bit_lock() is used to mediate
concurrent calls of ohci_flush_iso_completions(). However, the ad-hoc
usage of atomic operations is not preferable.

This commit uses mutex_trylock() as the similar operations. The core
function is responsible for the mediation, instead of 1394 OHCI driver.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: core: expose kernel API to schedule work item to process isochronous context

In packet-per-buffer mode for isochronous context of 1394 OHCI, software
can schedule hardIRQ to the buffer in

firewire: core: expose kernel API to schedule work item to process isochronous context

In packet-per-buffer mode for isochronous context of 1394 OHCI, software
can schedule hardIRQ to the buffer in which the content of isochronous
packet is processed. The actual behaviour is different between isochronous
receive (IR) and transmit (IT) contexts in respect to isochronous cycle in
which the hardIRQ occurs.

In IR context, the hardIRQ occurs when the buffer is filled actually by
the content of received packet. If there are any isochronous cycles in
which the packet transmission is skipped, it is postponed to generate
the hardIRQ in respect to the isochronous cycle. In IT context, software
can schedule the content of packet every isochronous cycle including
skipping, therefore the hardIRQ occurs in the isochronous cycle to which
the software scheduled.

ALSA firewire stack uses the packet-per-buffer mode for both IR/IT
contexts. To process time stamp per packet (or per sample in some cases)
steadily for media clock recovery against unexpected transmission skips,
it uses an IT context to operate all of isochronous contexts by calls of
fw_iso_context_flush_completions() in the bottom-half of hardIRQ for the
IT context.

Although it looks well to handle all of isochronous contexts in a single
bottom-half context, it relatively takes longer time. In the future code
integration (not yet), it is possible to apply parallelism method to
process these context. In the case, it is useful to allow unit drivers to
schedule work items to process these isochronous contexts.

As a preparation, this commit exposes
fw_iso_context_schedule_flush_completions() as a kernel API available by
unit drivers. It is renamed from fw_iso_context_queue_work() since it is
a counter part of fw_iso_context_flush_completions().

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: core: add local API to queue work item to workqueue specific to isochronous contexts

In the previous commit, the workqueue is added per the instance of fw_card
structure for isochronous co

firewire: core: add local API to queue work item to workqueue specific to isochronous contexts

In the previous commit, the workqueue is added per the instance of fw_card
structure for isochronous contexts. The workqueue is designed to be used by
the implementation of fw_card_driver structure underlying the fw_card.

This commit adds some local APIs to be used by the implementation.

Tested-by: Edmund Raile <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: core: allocate workqueue to handle isochronous contexts in card

This commit adds a workqueue dedicated for isochronous context processing.

The workqueue is allocated per instance of fw_ca

firewire: core: allocate workqueue to handle isochronous contexts in card

This commit adds a workqueue dedicated for isochronous context processing.

The workqueue is allocated per instance of fw_card structure to satisfy the
following characteristics descending from 1394 OHCI specification:

In 1394 OHCI specification, memory pages are reserved to each isochronous
context dedicated to DMA transmission. It allows to operate these
per-context pages concurrently. Software can schedule hardware interrupt
for several isochronous context to the same cycle, thus WQ_UNBOUND is
specified. Additionally, it is sleepable to operate the content of pages,
thus WQ_BH is not used.

The isochronous context delivers the packets with time stamp, thus
WQ_HIGHPRI is specified for semi real-time data such as IEC 61883-1/6
protocol implemented by ALSA firewire stack. The isochronous context is not
used by the implementation of SCSI over IEEE1394 protocol (sbp2), thus
WQ_MEM_RECLAIM is not specified.

It is useful for users to adjust cpu affinity of the workqueue depending
on their work loads, thus WQ_SYS is specified to expose the attributes to
user space.

Tested-by: Edmund Raile <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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Revert "firewire: Annotate struct fw_iso_packet with __counted_by()"

This reverts commit d3155742db89df3b3c96da383c400e6ff4d23c25.

The header_length field is byte unit, thus it can not express the

Revert "firewire: Annotate struct fw_iso_packet with __counted_by()"

This reverts commit d3155742db89df3b3c96da383c400e6ff4d23c25.

The header_length field is byte unit, thus it can not express the number of
elements in header field. It seems that the argument for counted_by
attribute can have no arithmetic expression, therefore this commit just
reverts the issued commit.

Suggested-by: Gustavo A. R. Silva <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: Annotate struct fw_iso_packet with __counted_by()

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by c

firewire: Annotate struct fw_iso_packet with __counted_by()

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

Signed-off-by: Gustavo A. R. Silva <[email protected]>
Link: https://lore.kernel.org/r/ZgIrOuR3JI/jzqoH@neat
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: make fw_bus_type const

Now that the driver core can properly handle constant struct bus_type,
move the fw_bus_type variable to be a constant structure as well,
placing it into read-only me

firewire: make fw_bus_type const

Now that the driver core can properly handle constant struct bus_type,
move the fw_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Takashi Sakamoto <[email protected]>
Cc: [email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Link: https://lore.kernel.org/r/2023121931-skydiver-dodgy-d1bd@gregkh
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: Replace zero-length array with flexible-array member

Zero-length and one-element arrays are deprecated, and we are moving
towards adopting C99 flexible-array members, instead.

Address the

firewire: Replace zero-length array with flexible-array member

Zero-length and one-element arrays are deprecated, and we are moving
towards adopting C99 flexible-array members, instead.

Address the following warnings found with GCC-13 and
-fstrict-flex-arrays=3 enabled:
sound/firewire/amdtp-stream.c: In function ‘build_it_pkt_header’:
sound/firewire/amdtp-stream.c:694:17: warning: ‘generate_cip_header’ accessing 8 bytes in a region of size 0 [-Wstringop-overflow=]
694 | generate_cip_header(s, cip_header, data_block_counter, syt);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sound/firewire/amdtp-stream.c:694:17: note: referencing argument 2 of type ‘__be32[2]’ {aka ‘unsigned int[2]’}
sound/firewire/amdtp-stream.c:667:13: note: in a call to function ‘generate_cip_header’
667 | static void generate_cip_header(struct amdtp_stream *s, __be32 cip_header[2],
| ^~~~~~~~~~~~~~~~~~~

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [1].

Link: https://github.com/KSPP/linux/issues/21
Link: https://github.com/KSPP/linux/issues/303
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
Signed-off-by: Gustavo A. R. Silva <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/r/ZHT0V3SpvHyxCv5W@work
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: core: implement variations to send request and wait for response with time stamp

In the previous commit, the core function of Linux FireWire subsystem
was changed for two cases to operate

firewire: core: implement variations to send request and wait for response with time stamp

In the previous commit, the core function of Linux FireWire subsystem
was changed for two cases to operate asynchronous transaction with or
without time stamp.

This commit changes kernel API for the two cases. Current kernel API,
fw_send_request(), is changed to be static inline function to call
__fw_send_request(), which receives two argument for union and flag of
callback function. The new kernel API, fw_send_request_with_tstamp() is
also added as static inline function, too. When calling, the two
arguments are copied to internal structure, then used in softIRQ
context.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: core: use union for callback of transaction completion

In 1394 OHCI, the OUTPUT_LAST descriptor of Asynchronous Transmit (AT)
request context has timeStamp field, in which 1394 OHCI contro

firewire: core: use union for callback of transaction completion

In 1394 OHCI, the OUTPUT_LAST descriptor of Asynchronous Transmit (AT)
request context has timeStamp field, in which 1394 OHCI controller
record the isochronous cycle when the packet was sent for the request
subaction. Additionally, for the case of split transaction in IEEE 1394,
Asynchronous Receive (AT) request context is used for response subaction
to finish the transaction. The trailer quadlet of descriptor in the
context has timeStamp field, in which 1394 OHCI controller records the
isochronous cycle when the packet arrived.

Current implementation of 1394 OHCI controller driver stores values of
both fields to internal structure as time stamp, while Linux FireWire
subsystem provides no way to access to it. When using asynchronous
transaction service provided by the subsystem, callback function is passed
to kernel API. The prototype of callback function has the lack of argument
for the values.

This commit adds a new callback function for the purpose. It has an
additional argument to point to the constant array with two elements. For
backward compatibility to kernel space, a new union is also adds to wrap
two different prototype of callback function. The fw_transaction structure
has the union as a member and a boolean flag to express which function
callback is available.

The core function is changed to handle the two cases; with or without
time stamp. For the error path to process transaction, the isochronous
cycle is computed by current value of CYCLE_TIMER register in 1394 OHCI
controller. Especially for the case of timeout of split transaction, the
expected isochronous cycle is computed.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Sakamoto <[email protected]>

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firewire: move fw_device() and fw_unit() to use container_of_const()

The driver core is changing to pass some pointers as const, so move
fw_device() and fw_unit() functions to use container_of_const

firewire: move fw_device() and fw_unit() to use container_of_const()

The driver core is changing to pass some pointers as const, so move
fw_device() and fw_unit() functions to use container_of_const() to
handle this change.

fw_device() and fw_unit() now properly keeps the const-ness of the
pointer passed into it, while as before it could be lost.

This also required turning fw_parent_device() into a macro to preserve
the const-ness of the pointer passed into it if necessary.

Cc: Stefan Richter <[email protected]>
Acked-by: Hans de Goede <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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firewire: cdev: obsolete NULL check to detect IEC 61883-1 FCP region

In the character device, the listener to address space should distinguish
whether the request is to IEC 61883-1 FCP region or not

firewire: cdev: obsolete NULL check to detect IEC 61883-1 FCP region

In the character device, the listener to address space should distinguish
whether the request is to IEC 61883-1 FCP region or not. The user space
application needs to access to the object of request in enough later by
read(2), while the core function releases the object of request in the FCP
case after completing the callback to handler.

The handler guarantees the access safe by some way. It's done by
duplication of the object after NULL check to the request, since core
function passes NULL in the FCP case. It's inconvenient since the object
of request includes some helpful information. It's better to add another
way to check whether the request is to FCP region or not.

Conveniently the file of transaction layer includes local implementation
for the purpose. This commit moves it to module local file and use it
instead of the NULL check, then the result of check is stored to
per-client data for the inbound transaction so that the result can be
referred by later to release the data.

Signed-off-by: Takashi Sakamoto <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>

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firewire: add kernel API to access packet structure in request structure for AR context

In 1394 OHCI specification, descriptor of Asynchronous Receive DMA context
has timeStamp field in its trailer

firewire: add kernel API to access packet structure in request structure for AR context

In 1394 OHCI specification, descriptor of Asynchronous Receive DMA context
has timeStamp field in its trailer quadlet. The field is written by
the host controller for the time to receive asynchronous request
subaction in isochronous cycle time.

In Linux FireWire subsystem, the value of field is stored to fw_packet
structure and copied to fw_request structure as the part. The fw_request
structure is hidden from unit driver and passed as opaque pointer when
calling registered handler. It's inconvenient to the unit driver which
needs timestamp of packet.

This commit adds kernel API to pick up timestamp from opaque pointer to
fw_request structure.

Signed-off-by: Takashi Sakamoto <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>

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firewire: add kernel API to access CYCLE_TIME register

1394 OHCI specification defined Isochronous Cycle Timer Register to get
value of CYCLE_TIME register defined by IEEE 1394 for CSR architecture

firewire: add kernel API to access CYCLE_TIME register

1394 OHCI specification defined Isochronous Cycle Timer Register to get
value of CYCLE_TIME register defined by IEEE 1394 for CSR architecture
defined by ISO/IEC 13213. Unit driver can calculate packet time by
compute with the value of CYCLE_TIME and timeStamp field in descriptor
of each isochronous and asynchronous context. The resolution of CYCLE_TIME
is 49.576 MHz, while the one of timeStamp is 8,000 Hz.

Current implementation of Linux FireWire subsystem allows the driver to
get the value of CYCLE_TIMER CSR register by transaction service. The
transaction service has overhead in regard of access to MMIO register.

This commit adds kernel API for unit driver to access the register
directly.

Signed-off-by: Takashi Sakamoto <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>

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firewire: Remove function callback casts

In 1394 OHCI specification, Isochronous Receive DMA context has several
modes. One of mode is 'BufferFill' and Linux FireWire stack uses it to
receive isochr

firewire: Remove function callback casts

In 1394 OHCI specification, Isochronous Receive DMA context has several
modes. One of mode is 'BufferFill' and Linux FireWire stack uses it to
receive isochronous packets for multiple isochronous channel as
FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL.

The mode is not used by in-kernel driver, while it's available for
userspace. The character device driver in firewire-core includes
cast of function callback for the mode since the type of callback
function is different from the other modes. The case is inconvenient
to effort of Control Flow Integrity builds due to
-Wcast-function-type warning.

This commit removes the cast. A static helper function is newly added
to initialize isochronous context for the mode. The helper function
arranges isochronous context to assign specific callback function
after call of existent kernel API. It's noticeable that the number of
isochronous channel, speed, and the size of header are not required for
the mode. The helper function is used for the mode by character device
driver instead of direct call of existent kernel API.

The same goal can be achieved (in the ioctl_create_iso_context function)
without this helper function as follows:
- Call the fw_iso_context_create function passing NULL to the callback
parameter.
- Then setting the context->callback.sc or context->callback.mc
variables based on the a->type value.

However using the helper function created in this patch makes code more
clear and declarative. This way avoid the call to a function with one
purpose to achieved another one.

Co-developed-by: Takashi Sakamoto <[email protected]>
Signed-off-by: Takashi Sakamoto <[email protected]>
Co-developed-by: Stefan Richter <[email protected]>
Signed-off-by: Stefan Richter <[email protected]>
Signed-off-by: Oscar Carter <[email protected]>
Reviewed-by: Takashi Sakamoto <[email protected]>
Testeb-by: Takashi Sakamoto<[email protected]>
Signed-off-by: Gustavo A. R. Silva <[email protected]>

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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ALSA: firewire/bebob: Add a workaround for M-Audio special Firewire series

In post commit, a quirk of this firmware about transactions is reported.
This commit apply a workaround for this quirk.

Th

ALSA: firewire/bebob: Add a workaround for M-Audio special Firewire series

In post commit, a quirk of this firmware about transactions is reported.
This commit apply a workaround for this quirk.

They often fail transactions due to gap_count mismatch. This state is changed
by generating bus reset.

The fw_schedule_bus_reset() is an exported symbol in firewire-core. But there
are no header for public. This commit moves its prototype from
drivers/firewire/core.h to include/linux/firewire.h.

This mismatch still affects bus management before generating this bus reset.
It still takes a time to call driver's probe() because transactions are still
often failed.

Signed-off-by: Takashi Sakamoto <[email protected]>
Signed-off-by: Takashi Iwai <[email protected]>

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firewire: don't use PREPARE_DELAYED_WORK

PREPARE_[DELAYED_]WORK() are being phased out. They have few users
and a nasty surprise in terms of reentrancy guarantee as workqueue
considers work items t

firewire: don't use PREPARE_DELAYED_WORK

PREPARE_[DELAYED_]WORK() are being phased out. They have few users
and a nasty surprise in terms of reentrancy guarantee as workqueue
considers work items to be different if they don't have the same work
function.

firewire core-device and sbp2 have been been multiplexing work items
with multiple work functions. Introduce fw_device_workfn() and
sbp2_lu_workfn() which invoke fw_device->workfn and
sbp2_logical_unit->workfn respectively and always use the two
functions as the work functions and update the users to set the
->workfn fields instead of overriding work functions using
PREPARE_DELAYED_WORK().

This fixes a variety of possible regressions since a2c1c57be8d9
"workqueue: consider work function when searching for busy work items"
due to which fw_workqueue lost its required non-reentrancy property.

Signed-off-by: Tejun Heo <[email protected]>
Acked-by: Stefan Richter <[email protected]>
Cc: [email protected]
Cc: [email protected] # v3.9+
Cc: [email protected] # v3.8.2+
Cc: [email protected] # v3.4.60+
Cc: [email protected] # v3.2.40+

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firewire: fix libdc1394/FlyCap2 iso event regression

Commit 18d627113b83 (firewire: prevent dropping of completed iso packet
header data) was intended to be an obvious bug fix, but libdc1394 and
Fly

firewire: fix libdc1394/FlyCap2 iso event regression

Commit 18d627113b83 (firewire: prevent dropping of completed iso packet
header data) was intended to be an obvious bug fix, but libdc1394 and
FlyCap2 depend on the old behaviour by ignoring all returned information
and thus not noticing that not all packets have been received yet. The
result was that the video frame buffers would be saved before they
contained the correct data.

Reintroduce the old behaviour for old clients.

Tested-by: Stepan Salenikovich <[email protected]>
Tested-by: Josep Bosch <[email protected]>
Cc: <[email protected]> # 3.4+
Signed-off-by: Clemens Ladisch <[email protected]>
Signed-off-by: Stefan Richter <[email protected]>

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firewire: introduce fw_driver.probe and .remove methods

FireWire upper layer drivers are converted from generic
struct driver.probe() and .remove()
to bus-specific
struct fw_driver.probe() a

firewire: introduce fw_driver.probe and .remove methods

FireWire upper layer drivers are converted from generic
struct driver.probe() and .remove()
to bus-specific
struct fw_driver.probe() and .remove().

The new .probe() adds a const struct ieee1394_device_id *id argument,
indicating the entry in the driver's device identifiers table which
matched the fw_unit to be probed. This new argument is used by the
snd-firewire-speakers driver to look up device-specific parameters and
methods. There is at least one other FireWire audio driver currently in
development in which this will be useful too.

The new .remove() drops the unused error return code.

Although all in-tree drivers are being converted to the new methods,
support for the old methods is left in place in this commit. This
allows public developer trees to merge this commit and then move to the
new fw_driver methods.

Signed-off-by: Stefan Richter <[email protected]>
Acked-by: Clemens Ladisch <[email protected]> (for sound/firewire/)
Cc: Peter Hurley <[email protected]> (for drivers/staging/fwserial/)

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firewire: addendum to address handler RCU conversion

Follow up on commit c285f6ff6787 "firewire: remove global lock around
address handlers, convert to RCU":

- address_handler_lock no longer seri

firewire: addendum to address handler RCU conversion

Follow up on commit c285f6ff6787 "firewire: remove global lock around
address handlers, convert to RCU":

- address_handler_lock no longer serializes the address handler, only
its function to serialize updates to the list of handlers remains.
Rename the lock to address_handler_list_lock.

- Callers of fw_core_remove_address_handler() must be able to sleep.
Comment on this in the API documentation.

- The counterpart fw_core_add_address_handler() is by nature something
which is used in process context. Replace spin_lock_bh() by
spin_lock() in fw_core_add_address_handler() and in
fw_core_remove_address_handler(), and document that process context
is now required for fw_core_add_address_handler().

- Extend the documentation of fw_address_callback_t.

Signed-off-by: Stefan Richter <[email protected]>

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firewire: core: add is_local sysfs device attribute

Making this information available in sysfs allows to differentiate
between controllers in the local and remote Linux PCs, and thus is
useful for s

firewire: core: add is_local sysfs device attribute

Making this information available in sysfs allows to differentiate
between controllers in the local and remote Linux PCs, and thus is
useful for servers that are started with udev rules.

Signed-off-by: Clemens Ladisch <[email protected]>
Signed-off-by: Stefan Richter <[email protected]>

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firewire: core: make address handler length 64 bits

The type of the length field of the fw_address_handler structure was
size_t, which restricted it to 32 bits on 32-bit architectures.

While making

firewire: core: make address handler length 64 bits

The type of the length field of the fw_address_handler structure was
size_t, which restricted it to 32 bits on 32-bit architectures.

While making it u32 would match the userspace API, all calculations on
this field use 64 bits anyway, and the ability to use 4 GB or larger
address ranges is useful in the kernel.

Signed-off-by: Clemens Ladisch <[email protected]>
Signed-off-by: Stefan Richter <[email protected]>

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