Commit Graph

15 Commits

Author SHA1 Message Date
Stefan Richter fe43d6d9cf firewire: core: align driver match with modalias
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>
2010-03-24 22:01:47 +01:00
Stefan Richter 5ae73518cb firewire: core: fix Model_ID in modalias
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>
2010-03-24 22:01:47 +01:00
Stefan Richter fd6e0c5181 firewire: core: rename an internal function
according to what it really does.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-02-24 20:36:54 +01:00
Stefan Richter 137d9ebfdb firewire: core: fix an information leak
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>
2010-02-24 20:36:54 +01:00
Stefan Richter 58aaa54276 firewire: core: increase stack size of config ROM reader
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>
2010-02-24 20:36:54 +01:00
Stefan Richter 2799d5c5f9 firewire: core: don't fail device creation in case of too large config ROM blocks
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>
2010-02-24 20:36:54 +01:00
Stefan Richter d54423c62c firewire: core: fix "giving up on config rom" with Panasonic AG-DV2500
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>
2010-02-24 20:36:54 +01:00
Stefan Richter 13b302d0a2 firewire: qualify config ROM cache pointers as const pointers
Several config ROM related functions only peek at the ROM cache; mark
their arguments as const pointers.  Ditto fw_device.config_rom and
fw_unit.directory, as the memory behind them is meant to be write-once.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-12-29 19:58:17 +01:00
Stefan Richter 3c2c58cb33 firewire: core: fw_csr_string addendum
Witespace and comment changes, and a different way to say i + 1 < end.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-12-29 19:58:17 +01:00
Clemens Ladisch 1f8fef7b33 firewire: add fw_csr_string() helper function
The core (sysfs attributes), the firedtv driver, and possible future
drivers all read strings from some configuration ROM directory.  Factor
out the generic code from show_text_leaf() into a new helper function,
modified slightly to handle arbitrary buffer sizes.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-12-29 19:58:17 +01:00
David Brownell a4dbd6740d driver model: constify attribute groups
Let attribute group vectors be declared "const".  We'd
like to let most attribute metadata live in read-only
sections... this is a start.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-09-15 09:50:47 -07:00
Stefan Richter 837ec787d8 firewire: core: don't update Broadcast_Channel if RFC 2734 conditions aren't met
This extra check will avoid Broadcast_Channel register related traffic
to many IIDC, SBP-2, and AV/C devices which aren't IRMC or have a
max_rec < 8 (i.e. support < 512 bytes async payload).  This avoids a
little bit of traffic after bus reset and is even more careful with
devices which don't implement this CSR.

The assumption is that no other protocol than IP over 1394 uses the
broadcast channel for streams.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-14 11:57:06 +02:00
Stefan Richter 099d54143e firewire: core: prepare for non-core children of card devices
The IP-over-1394 driver will add child devices beneath card devices
which are not of type fw_device.  Hence firewire-core's callbacks in
device_for_each_child() and device_find_child() need to check for the
device type now.

Initial version written by Jay Fenlason.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-06 21:45:50 +02:00
Stefan Richter e5110d011e firewire: add parent-of-unit accessor
Retrieval of an fw_unit's parent is a common pattern in high-level code.
Wrap it up as device = fw_parent_device(unit).

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-06 21:45:50 +02:00
Stefan Richter e71d31da06 firewire: rename source files
The source files of firewire-core, firewire-ohci, firewire-sbp2, i.e.
 "drivers/firewire/fw-*.c"
are renamed to
 "drivers/firewire/core-*.c",
 "drivers/firewire/ohci.c",
 "drivers/firewire/sbp2.c".

The old fw- prefix was redundant to the directory name.  The new core-
prefix distinguishes the files according to which driver they belong to.

This change comes a little late, but still before further firewire
drivers are added as anticipated RSN.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-06-05 16:26:18 +02:00