The definition of struct fw_cdev_iso_packet seems to imply that the
header_length must be quadlet-aligned, and in fact, specifying an
unaligned header has never really worked when using multiple packet
structures, because the position of the next control word is computed by
rounding the header_length _down_, so the last one to three bytes of the
header would overlap the next control word.
To avoid this problem, check that the header length is properly aligned.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
In receive contexts, reject packets with header_length==0. This would
be an instruction to queue zero packets which would not make sense.
This prevents a division by zero in the OHCI driver.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The driver match strategy was:
- Match vendor/model/specifier/version of the unit directory.
- If that was a miss, match vendor from the root directory and
model/specifier/version of the unit directory.
This was inconsistent with how the modalias string was constructed
until recently (take vendor/model from root directory and specifier/
version from unit directory). It was also inconsistent with how it is
done since the parent commit:
- Use vendor/model/specifier/version of the unit directory if possible,
- fall back to one or more of vendor/model/specifier/version from the
root directory depending on which ones are not present at the unit
directory.
Fix this inconsistency by sharing the ROM scanner function between
modalias printer function and driver match function.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The modalias string of devices that represent units on a FireWire node
did not show Module_ID entries within unit directories. This was
because firewire-core searched only the root directory of the
configuration ROM for a Model_ID entry.
We now search first the root directory, then the unit directory. IOW
honor a unit directory's Model_ID if present, otherwise fall back to the
root directory's model ID (if present).
Furthermore, apply the same change to Vendor_ID. This had the same
issue but it was less apparent because most devices provide Vendor_ID
only in the root directory.
And finally, also use this strategy for the remaining two IDs in the
modalias, Specifier_ID and Version. It does not actually make sense to
look for them elsewhere than in the unit directory because they are
mandatory there. However, a uniform search order simplifies the
implementation and has no adverse affect in practice.
Side notes:
- The older counterpart of this, nodemgr.c of ieee1394, looked for
Vendor_ID first in the root directory, then in the unit directory,
and for Model_ID only in the unit directory.
- There is a single mainline driver which requires Vendor_ID and
Model_ID --- the firedtv driver. This one worked because FireDTVs
provide Vendor_ID in the root directory and Model_ID identically in
root directory and unit directory.
- Apart from firedtv, there are currently no drivers known to me
(including userspace drivers) that look at the Vendor_ID or Model_ID
of the modalias.
Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Among the many entries in the TSB12LV22 errata list (TI literature
number SLLS312) is the following:
PCI Slave reads of the Cycle Timer register may occasionally get an
incorrect value.
Software may be able to validate value by reading the register
multiple times rapidly and evaluating for a reasonable difference.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de> (untested)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (added #define)
If the bandwidth allocation fails, the error must be returned in
*channel regardless of whether the channel allocation succeeded.
Checking for c >= 0 is not correct if no channel allocation was
requested, in which case this part of the code is reached with
c == -EINVAL.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
by the number of available isochronous DMA contexts and active quirks
which is occasionally useful information.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This bug was present in firewire-ohci since day one: The number of
available isochronous receive DMA contexts was mixed up with that of
available isochronous transmit DMA contexts.
This is harmless on a few chips which offer the same number of contexts
in both directions, but most chips nowadays implement only the standard
minimum of 4 IR contexts, but 8 IT contexts. If a user attempted to run
a lot of IR contexts at once, results with more than four were therefore
unpredictable. I suppose the controller would simply refuse to start
DMA of any unimplemented context.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This way, we can advise users of precompiled kernel packages to test
existing quirk fixes on chips which have not been listed yet, without
them having to build a kernel from source.
Note, to use this feature on a machine with more than one controller,
steps like these are necessary:
# lspci | grep 1394
# ls /sys/bus/pci/drivers/firewire_ohci/
# echo -n "0000:03:02.0" > /sys/bus/pci/drivers/firewire_ohci/unbind
# echo 2 > /sys/module/firewire_ohci/parameters/quirks
# echo -n "0000:03:02.0" > /sys/bus/pci/drivers/firewire_ohci/bind
# echo 0 > /sys/module/firewire_ohci/parameters/quirks
The parameter can also be used to switch off quirk flags that were
hardwired into firewire-ohci's quirks table. Simply specify a non-zero
quirks value but without any known flags, e.g. 0x100.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
We don't have a lot of quirks to take into account (especially since
dual-buffer IR is out of the picture), but still, a table-based approach
is more organized than a series of if () clauses.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The config_rom struct members are only accessed during relatively
infrequent self-ID-complete interrupts and only if the local config ROM
was changed, while the ar_, at_, ir_, it_ members are used very
frequently during I/O. Hence move the config_rom members further down.
More importantly, make the huge self_id_buffer member the last one; this
is only accessed in self-ID-complete interrupts.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This code was no longer used since 2.6.33, "firewire: ohci: always use
packet-per-buffer mode for isochronous reception" commit 090699c0. If
anybody needs this code in the future for special purposes, it can be
brought back in. But it must not be re-enabled by default; drivers
(kernelspace or userspace drivers) should only get this mode if they
explicitly request it.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
from array of char to union of structs. I already used a union to size
the buffer which holds ioctl arguments; more consequent is to define it
as an instance of this union in the first place.
Also rename several local variables from "request" to "a"(rgument) since
the term request can be mistaken to mean a transaction subaction, e.g.
an instance of struct fw_request.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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 <stefanr@s5r6.in-berlin.de>
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/242
We 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 <stefanr@s5r6.in-berlin.de>
If a device exposes a sparsely populated configuration ROM,
firewire-core's sysfs interface and character device file interface
showed random data in the gaps between config ROM blocks. Fix this by
zero-initialization of the config ROM reader's scratch buffer.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The stack size of 16 was artificially chosen and may be too small in
extreme cases. A device won't be accessible then.
Since it doesn't really matter to the slab allocator whether we ask for
1088 bytes or 2048 bytes of scratch memory, just allocate 2048 bytes for
the sum of temporary config ROM image and stack, and we will never ever
overflow the stack (because there simply can't be more stack items than
ROM entries).
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
It never happened yet, but better safe than sorry: If a device's config
ROM contains a block which overlaps the boundary at 0xfffff00007ff, just
ignore that one block instead of refusing to add the device
representation. That way, upper layers (kernelspace or userspace
drivers) might still be able to use the device to some degree.
That's better than total inaccessibility of the device. Worse, the core
would have logged only a generic "giving up on config rom" message which
could only be debugged by feeding a firewire-ohci debug logging session
through a config ROM interpreter, IOW would likely remain undiagnosed.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The Panasonic AG-DV2500 tape deck contains an invalid entry in its
configuration ROM root directory: A leaf pointer with the undefined key
ID 0 and an offset that points way out of the standard config ROM area.
This caused firewire-core to dismiss the device with the generic log
message "giving up on config rom for node id...", after which it was of
course impossible to access the tape deck with dvgrab or any other
program. https://bugzilla.redhat.com/show_bug.cgi?id=449252#c29
The fix is to simply ignore this invalid ROM entry and proceed to read
the valid rest of the ROM. There is a catch though: When the kernel
later iterates over the ROM, it would be nasty having to check again for
such too large ROM offsets. Therefore we manipulate the defective or
unsupported ROM entry to become a harmless immediate entry that won't
have any side effects later (an entry with the value 0x00000000).
Reported-by: George Chriss
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Clemens Ladisch
Stefan Richter
Linus Torvalds