21 Jun, 2010
2 commits
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The problem:
A target-like userspace driver, e.g. AV/C target or SBP-2/3 target,
needs to be able to act as responder and requester. In the latter role,
it needs to send requests to nods from which it received requests. This
is currently impossible because fw_cdev_event_request lacks information
about sender node ID.
Reported-by: Jay FenlasonLibffado + libraw1394 + firewire-core is currently unable to drive two
or more audio devices on the same bus.
Reported-by: Arnold KrilleThis is because libffado requires destination node ID of FCP requests
and sender node ID of FCP responses to match. It even prohibits
libffado from working with a bus on which libraw1394 opens a /dev/fw* as
default ioctl device that does not correspond with the audio device.
This is because libraw1394 does not receive the sender node ID from the
kernel.Moreover, fw_cdev_event_request makes it impossible to tell unicast and
broadcast write requests apart.The fix:
Add a replacement of struct fw_cdev_event_request request, boringly
called struct fw_cdev_event_request2. The new event will be sent to a
userspace client instead of the old one if the client claims
compatibility with ABI version 4 or later.libraw1394 needs to be extended to make use of the new event, in order
to properly support libffado and other FCP or address range mapping
users who require correct sender node IDs.Further notes:
While we are at it, change back the range of possible values of
fw_cdev_event_request.tcode to 0x0...0xb like in ABI version -
libraw1394 v2.0.0...v2.0.5 takes FW_CDEV_VERSION from an externally
installed header file and uses it to declare its own implementation
level in FW_CDEV_IOC_GET_INFO. This is wrong; it should set the real
version for which it was actually written.If we add features to the kernel ABI that require the kernel to check
a client's implementation level, we can not trust the client version if
it was set from FW_CDEV_VERSION.Hence freeze FW_CDEV_VERSION at the current value (no damage has been
done yet), clearly document FW_CDEV_VERSION as a dummy version and what
clients are expected to do with fw_cdev_get_info.version, and use a new
defined constant (which is not placed into the exported header file) as
kernel implementation level.Note, in order to check in client program source code which features are
present in an externally installed linux/firewire-cdev.h, use
preprocessor directives like
#ifdef FW_CDEV_IOC_ALLOCATE_ISO_RESOURCE
or
#ifdef FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED
instead of a check of FW_CDEV_VERSION.Signed-off-by: Stefan Richter
10 Apr, 2010
2 commits
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Signed-off-by: Stefan Richter
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Add the missing documentation for iso packets.
Signed-off-by: Clemens Ladisch
Signed-off-by: Stefan Richter
25 Feb, 2010
2 commits
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so that clients can detect whether the FW_CDEV_IOC_GET_CYCLE_TIMER ioctl
is reliable (on all tested controllers, especially the widely used VIA
controllers, also NEC controllers, see commits b677532b and 1c1517ef).Also add a comment on the 2.6.32 iso xmit enhancement and on dual-buffer
IR having been disabled in 2.6.33.Signed-off-by: Stefan Richter
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The system time from CLOCK_REALTIME is not monotonic, hence problematic
for the main user of the FW_CDEV_IOC_GET_CYCLE_TIMER ioctl. This issue
exists in its successor ABI, i.e. raw1394, too.
http://subversion.ffado.org/ticket/242We now offer an alternative ioctl which lets the caller choose between
CLOCK_REALTIME, CLOCK_MONOTONIC, and CLOCK_MONOTONIC_RAW as source of
the local time, very similar to the clock_gettime libc function. The
format of the local time return value matches that of clock_gettime
(seconds and nanoseconds, instead of a single microseconds value from
the existing ioctl).Signed-off-by: Stefan Richter
27 Jan, 2010
1 commit
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struct fw_cdev_add_descriptor.length is in quadlets, not in bytes.
Also remove any doubts about the endianess of descriptor data.Signed-off-by: Stefan Richter
30 Dec, 2009
1 commit
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Control of more than one AV/C device at once --- e.g. camcorders, tape
decks, audio devices, TV tuners --- failed or worked only unreliably,
depending on driver implementation. This affected kernelspace and
userspace drivers alike and was caused by firewire-core's inability to
accept multiple registrations of FCP listeners.The fix allows multiple address handlers to be registered for the FCP
command and response registers. When a request for these registers is
received, all handlers are invoked, and the Firewire response is
generated by the core and not by any handler.The cdev API does not change, i.e., userspace is still expected to send
a response for FCP requests; this response is silently ignored.Signed-off-by: Clemens Ladisch
Signed-off-by: Stefan Richter (changelog, rebased, whitespace)
25 Mar, 2009
12 commits
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This changes the as yet unreleased FW_CDEV_IOC_SEND_STREAM_PACKET ioctl
to generate an fw_cdev_event_response event just like the other two
ioctls for asynchronous request transmission do. This way, clients get
feedback on successful or unsuccessful transmission.This also adds input validation for length, tag, channel, sy, speed.
Signed-off-by: Stefan Richter
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The access permissions and ownership or ACL of /dev/fw* character device
files will typically be set based on the device type of the respective
nodes, as obtained by firewire-core from descriptors in the device's
configuration ROM. An example policy is to deny write permission by
default but grant write permission to files of AV/C video and audio
devices and IIDC video devices.The FW_CDEV_IOC_ADD_DESCRIPTOR ioctl could be used to partly subvert
such a policy: Find a device file with relaxed permissions, use the
ioctl to add a descriptor with AV/C marker to the local node's ROM, thus
gain access to the local node's character device file. (This is only
possible if there are udev scripts installed which actively relax
permissions for known device types and if there is a device of such a
type connected.)Accessibility of the local node's device file is relevant to host
security if the host contains two or more IEEE 1394 link layer
controllers which are plugged into a single bus.Therefore change the ABI to deny FW_CDEV_IOC_ADD_DESCRIPTOR if the file
belongs to a remote node. (This change has no impact on known
implementers of the ABI: None of them uses the ioctl yet.)Also clarify the documentation: The ioctl affects all local nodes, not
just one local node.Cc: stable@kernel.org
Signed-off-by: Stefan Richter -
The as yet unreleased FW_CDEV_IOC_GET_SPEED ioctl puts only a single
integer into the parameter buffer. We can use ioctl()'s return value
instead.(Also: Some whitespace change in firewire-cdev.h.)
Signed-off-by: Stefan Richter
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Allow userspace and other firewire drivers (fw-ipv4 I'm looking at
you!) to send Asynchronous Transmit Streams as described in 7.8.3 of
release 1.1 of the 1394 Open Host Controller Interface Specification.Signed-off-by: Jay Fenlason
Signed-off-by: Stefan Richter (tweaks) -
Some fixes:
- Remove stale documentation.
- Fix a != vs. == thinko that got in the way of channel management.
- Try bandwidth deallocation even if channel deallocation failed.A simplification:
- fw_cdev_allocate_iso_resource.channels is now ordered like
libdc1394's dc1394_iso_allocate_channel() channels_allowed
argument.By the way, I looked closer at cards from NEC, TI, and VIA, and noticed
that they all don't implement IEEE 1394a behaviour which is meant to
deviate from IEEE 1212's notion of lock compare-swap. This means that
we have to do two lock transactions instead of one in many cases where
one transaction would already succeed on a fully 1394a compliant IRM.Signed-off-by: Stefan Richter
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Necessary due to
Date: Tue, 22 Jul 2008 23:23:40 -0700
From: David Moore
Subject: firewire: Include iso timestamp in headers when header_size > 4Side note: The lack of upwards compatibility sounds worse than it is.
All existing client implementations, libraw1394 and libdc1394, set
header_size = 4. And since the ABI v1 behaviour does not offer any
advantages over the new behaviour, we deliberately do not provide the
old behaviour anymore.Also add documentation about the format of fw_cdev_get_cycle_timer which
may be used in conjunction with the timestamp of iso packets but has a
different format.Signed-off-by: Stefan Richter
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Write transactions to the broadcast node ID are a convenient way to
trigger functions of multiple nodes at once. IIDC is a protocol which
can make use of this if multiple cameras with same command_regs_base are
connected at the same bus.Based on
Date: Wed, 10 Sep 2008 11:32:16 -0400
From: Jay Fenlason
Subject: [patch] SEND_BROADCAST_REQUEST
Changes: ioctl_send_request() and ioctl_send_broadcast_request() now
share code. Broadcast speed corrected to S100. Check for proper tcode.Signed-off-by: Stefan Richter
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While the speed of asynchronous transactions is automatically chosen by
the kernel, the speed of isochronous streams has to be chosen by the
initiating client.In case of 1394a bus topologies, the maximum possible speed could be
figured out with some effort by evaluation of the remote node's link
speed field in the config ROM, the local node's link speed field, and
the PHY speeds and topologic information in the local node's or IRM's
topology map CSR. However, this does not work in case of 1394b buses.Hence add an ioctl to export the maximum speed which the kernel already
determined.Signed-off-by: Stefan Richter
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This adds ioctls for allocation and deallocation of a channel or/and
bandwidth without auto-reallocation and without auto-deallocation.The benefit of these ioctls is that libraw1394-style isochronous
resource management can be implemented without write access to the IRM's
character device file.Signed-off-by: Stefan Richter
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Based on
Date: Tue, 18 Nov 2008 11:41:27 -0500
From: Jay Fenlason
Subject: [Patch V4] Add ISO resource management support
with several changes to the ABI and implementation. Only the part of
the ABI which enables auto-reallocation and auto-deallocation is
included here.This implements ioctls for kernel-assisted allocation of isochronous
channels and isochronous bandwidth. The benefits are:
- The client does not have to have write access to the /dev/fw* device
corresponding to the IRM.
- The client does not have to perform reallocation after bus resets.
- Channel and bandwidth are deallocated by the kernel if the file is
closed before the client deallocated the resources. Thus resources
are released even if the client crashes.It is anticipated that future in-kernel code (firewire-core IRM code;
the firewire port of firedtv), will use the fw-iso.c portions of this
code too.Signed-off-by: Stefan Richter
Tested-by: David Moore -
The FW_CDEV_IOC_GET_INFO ioctl looks at client->device->config_rom, not
at the local node's config ROM.We could fix the implementation or the documentation. I believe the way
how it is currently implemented is more useful than the way how it is
currently documented. In fact, libdc1394 uses the ABI already as
implemented, not as documented. Hence let's change the documentation.Signed-off-by: Stefan Richter
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Reported-by: Jay Fenlason
Signed-off-by: Stefan Richter
16 Oct, 2008
1 commit
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Signed-off-by: Jay Fenlason
Signed-off-by: Stefan Richter
17 Oct, 2007
1 commit
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This duplicates the read cycle timer feature of raw1394 (added in Linux
2.6.21) in firewire-core's userspace ABI. The argument to the ioctl is
reordered though to ensure 32/64 bit compatibility.Signed-off-by: Stefan Richter
Signed-off-by: Kristian Høgsberg
10 Jul, 2007
1 commit
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The isochronous packet format is still not documented, but this
is a good first step.Signed-off-by: Kristian Høgsberg
Signed-off-by: Stefan Richter (format, wording)
01 Jun, 2007
1 commit
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The struct is part of the userspace interface and can not use
bitfields. This patch replaces the bitfields with a __u32 'control'
word and provides access macros to set the bits.Signed-off-by: Kristian Høgsberg
Signed-off-by: Stefan Richter
11 May, 2007
2 commits
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Signed-off-by: Kristian Hoegsberg
Signed-off-by: Stefan Richter -
Signed-off-by: Kristian Hoegsberg
Signed-off-by: Stefan Richter
01 May, 2007
1 commit
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Signed-off-by: Kristian Høgsberg
Signed-off-by: Stefan Richter