763 Commits

Author SHA1 Message Date
Stefan Richter
604f451678 firewire: cdev: freeze FW_CDEV_VERSION due to libraw1394 bug
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 <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Stefan Richter
0244f57302 firewire: cdev: count references of cards during inbound transactions
If a request comes in to an address range managed by a userspace driver
i.e. <linux/firewire-cdev.h> client, the card instance of request and
response may differ from the card instance of the client device.
Therefore we need to take a reference of the card until the response was
sent.

I thought about putting the reference counting into core-transaction.c,
but the various high-level drivers besides cdev clients (firewire-net,
firewire-sbp2, firedtv) use the card pointer in their fw_address_handler
address_callback method only to look up devices of which they already
hold the necessary references.  So this seems to be a specific
firewire-cdev issue which is better addressed locally.

We do not need the reference
  - in case of FCP_REQUEST or FCP_RESPONSE requests because then the
    firewire-core will send the split transaction response for us
    already in the context of the request handler,
  - if it is the same card as the client device's because we hold a
    card reference indirectly via teh client->device reference.
To keep things simple, we take the reference nevertheless.

Jay Fenlason wrote:
> there's no way for the core to tell cdev "this card is gone,
> kill any inbound transactions on it", while cdev holds the transaction
> open until userspace issues a SEND_RESPONSE ioctl, which may be a very,
> very long time.  But when it does, it calls fw_send_response(), which
> will dereference the card...
>
> So how unhappy are we about userspace potentially holding a fw_card
> open forever?

While termination of inbound transcations at card removal could be
implemented, it is IMO not worth the effort.  Currently, the effect of
holding a reference of a card that has been removed is to block the
process that called the pci_remove of the card.  This is
  - either a user process ran by root.  Root can find and kill processes
    that have /dev/fw* open, if desired.
  - a kernel thread (which one?) in case of hot removal of a PCCard or
    ExpressCard.
The latter case could be a problem indeed.  firewire-core's card
shutdown and card release should probably be improved not to block in
shutdown, just to defer freeing of memory until release.

This is not a new problem though; the same already always happens with
the client->device->card without the need of inbound transactions or
other special conditions involved, other than the client not closing the
file.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Jay Fenlason
08bd34c98d firewire: cdev: fix responses to nodes at different card
My box has two firewire cards in it: card0 and card1.
My application opens /dev/fw0 (card 0) and allocates an address space.
The core makes the address space available on both cards.
Along comes the remote device, which sends a READ_QUADLET_REQUEST to
card1.  The request gets passed up to my application, which calls
ioctl_send_response().

ioctl_send_response() then calls fw_send_response() with card0,
because that's the card it's bound to.
Card0's driver drops the response, because it isn't part of
a transaction that it has outstanding.

So in core-cdev: handle_request(), we need to stash the
card of the inbound request in the struct inbound_transaction_resource and
use that card to send the response to.

The hard part will be refcounting the card correctly
so it can't get deallocated while we hold a pointer to it.

Here's a trivial patch, which does not do the card refcounting, but at
least demonstrates what the problem is.

Note that we can't depend on the fact that the core-cdev:client
structure holds a card open, because in this case the card it holds
open is not the card the request came in on.

..and there's no way for the core to tell cdev "this card is gone,
kill any inbound transactions on it", while cdev holds the transaction
open until userspace issues a SEND_RESPONSE ioctl, which may be a very,
very long time.  But when it does, it calls fw_send_response(), which
will dereference the card...

So how unhappy are we about userspace potentially holding a fw_card
open forever?

Signed-off-by: Jay Fenlason <fenlason@redhat.com>

Reference counting to be addressed in a separate change.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (whitespace)
2010-06-20 23:11:56 +02:00
Clemens Ladisch
bdfe273ee5 firewire: cdev: fix race in iso context creation
Protect the client's iso context pointer against a race that can happen
when more than one creation call is executed at the same time.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:56 +02:00
Stefan Richter
33e553fe2b firewire: remove an unused function argument
void (*fw_address_callback_t)(..., int speed, ...) is the speed that a
remote node chose to transmit a request to us.  In case of split
transactions, firewire-core will transmit the response at that speed.

Upper layer drivers on the other hand (firewire-net, -sbp2, firedtv, and
userspace drivers) cannot do anything useful with that speed datum,
except log it for debug purposes.  But data that is merely potentially
(not even actually) used for debug purposes does not belong into the API.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 23:11:55 +02:00
Stefan Richter
56d04cb189 firewire: core: remove an unnecessary zero initialization
All of the fields of the iso_interrupt_event instance are overwritten
right after it was allocated.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-20 17:06:25 +02:00
Stefan Richter
ae86e81e43 firewire: core: remove unused variable
which caused gcc 4.6 to warn about
    variable 'destination' set but not used.

Since the hardware ensures that we receive only response packets with
proper destination node ID (in a given bus generation), we have no use
for destination here in the core as well as in upper layers.

(This is different with request packets.  There we pass destination node
ID to upper layers because they may for example need to check whether
this was an unicast or broadcast request.)

Reported-and-Tested-By: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
0fcff4e393 firewire: rename CSR access driver methods
Rather than "read a Control and Status Registers (CSR) Architecture
register" I prefer to say "read a Control and Status Register".

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
b384cf1887 firewire: core: combine some repeated code
All of these CSRs have the same read/ write/ aynthing-else handling,
except for CSR_PRIORITY_BUDGET which might not be implemented.

The CSR_CYCLE_TIME read handler implementation accepted 4-byte-sized
block write requests before this change but this is just silly; the
register is only required to support quadlet read and write requests
like the other r/w CSR core and Serial-Bus-dependent registers.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
c8a94ded57 firewire: normalize STATE_CLEAR/SET CSR access interface
Push the maintenance of STATE_CLEAR/SET.abdicate down into the card
driver.  This way, the read/write_csr_reg driver method works uniformly
across all CSR offsets.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
db3c9cc105 firewire: replace get_features card driver hook
by feature variables in the fw_card struct.  The hook appeared to be an
unnecessary abstraction in the card driver interface.

Cleaner would be to pass those feature flags as arguments to
fw_card_initialize() or fw_card_add(), but the FairnessControl register
is in the SCLK domain and may therefore not be accessible while Link
Power Status is off, i.e. before the card->driver->enable call from
fw_card_add().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:41 +02:00
Stefan Richter
e847cc832b firewire: drop sizeof expressions from some request size arguments
In case of fw_card_bm_work()'s lock request, the present sizeof
expression is going to be wrong if somebody changes the fw_card's DMA
scratch buffer's size in the future.

In case of quadlet write requests, sizeof(u32) is just silly; it's 4.

In case of SBP-2 ORB pointer write requests, 8 is arguably quicker to
understand as the correct and only possible value than
sizeof(some_datum).

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:40 +02:00
Stefan Richter
65b2742ac0 firewire: 'add CSR_... support' addendum
Add a comment on which of the conflicting NODE_IDS specifications we
implement.  Reduce a comment on rather irrelevant register bits that can
all be looked up in the spec (or from now on in the code history).
Directly include the required indirectly included bug.h.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-19 13:01:40 +02:00
Clemens Ladisch
c374ab4242 firewire: core: always enable cycle master packets
As part of the bus manager responsibilities, make sure that the cycle
master sends cycle start packets.  This is needed when the old bus
manager disabled the cycle master's cmstr bit and there are iso-capable
nodes on the new bus.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:41:51 +02:00
Clemens Ladisch
e91b2787d0 firewire: allocate broadcast channel in hardware
On OHCI 1.1 controllers, let the hardware allocate the broadcast channel
automatically.  This removes a theoretical race condition directly after
a bus reset where it could be possible to read the channel allocation
register with channel 31 still being unallocated.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:40:49 +02:00
Clemens Ladisch
7e0e314f19 firewire: core: add CSR abdicate support
Implement the abdicate bit, which is required for bus manager
capable nodes and tested by the Base 1394 Test Suite.

Finally, something to do at a command reset!  :-)

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:37:15 +02:00
Clemens Ladisch
4ffb7a6a06 firewire: add CSR cmstr support
Implement the cmstr bit, which is required for cycle master capable
nodes and tested for by the Base 1394 Test Suite.

This bit allows the bus master to disable cycle start packets; there are
bus master implementations that actually do this.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:36:37 +02:00
Clemens Ladisch
3d1f46eb60 firewire: core: add CSR MAINT_UTILITY support
Implement the MAIN_UTILITY register, which is utterly optional
but useful as a safe target for diagnostic read/write/broadcast
transactions.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:35:37 +02:00
Clemens Ladisch
a1a1132bd8 firewire: add CSR PRIORITY_BUDGET support
If supported by the OHCI controller, implement the PRIORITY_BUDGET
register, which is required for nodes that can use asynchronous
priority arbitration.

To allow the core to determine what features the lowlevel device
supports, add a new card driver callback.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:35:06 +02:00
Clemens Ladisch
27a2329f82 firewire: add CSR BUSY_TIMEOUT support
Implement the BUSY_TIMEOUT register, which is required for nodes that
support retries.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:34:13 +02:00
Clemens Ladisch
a48777e03a firewire: add CSR BUS_TIME support
Implement the BUS_TIME register, which is required for cycle master
capable nodes and tested for by the Base 1393 Test Suite.  Even when
there is not yet bus master initialization support, this register allows
us to work together with other bus masters.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:33:07 +02:00
Clemens Ladisch
9ab5071cd4 firewire: add CSR CYCLE_TIME write support
The specification requires that CYCLE_TIME is writable so that it can be
initialized, so we better implement it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:26:48 +02:00
Clemens Ladisch
8e4b50f94e firewire: core: add CSR SPLIT_TIMEOUT support
Implement the SPLIT_TIMEOUT registers.  Besides being required by the
spec, this is desirable for some IIDC devices and necessary for many
audio devices to be able to increase the timeout from userspace.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:26:28 +02:00
Clemens Ladisch
446eba0d68 firewire: core: add CSR RESET_START support
This implements the RESET_START register (as a dummy) to make the Base
1394 Test Suite happy.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:25:46 +02:00
Clemens Ladisch
506f1a3193 firewire: add CSR NODE_IDS support
The NODE_IDS register, and especially its bus_id field, is quite
useless because 1394.1 requires that the bus_id field always stays
0x3ff.  However, the 1394 specification requires this register on all
transaction capable nodes, and the Base 1394 Test Suite tests for it,
so we better implement it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:25:19 +02:00
Clemens Ladisch
60d32970c5 firewire: add read_csr_reg driver callback
To prepare for the following additions of more OHCI-implemented CSR
registers, replace the get_cycle_time driver callback with a generic
CSR register callback.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:24:35 +02:00
Clemens Ladisch
3e07ec0eee firewire: core: add CSR STATE_CLEAR/STATE_SET support
The state registers are zero and read-only in this implementation, so
they are not of much use.  However, the specification requires that they
are present for transaction capable nodes, and the Base 1394 Test Suite
tests for them, so we better implement them.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:24:03 +02:00
Clemens Ladisch
bda3b8a1fa firewire: core: retry on local errors in bus manager election
When the candidate bus manager fails to do the lock request with which
it tries to become bus manager, it assumes that the current IRM is not
actually IRM capable and forces itself to become root.  However, if that
lock request failed because the local node itself was not able to send
it, then we cannot blame the current IRM and should not steal its
rootness.

In this case, RCODE_SEND_ERROR is likely to indicate a temporary error
condition such as exhausted tlabels or low memory, so we better try
again later.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:23:28 +02:00
Clemens Ladisch
153e397920 firewire: ohci: speed up PHY register accesses
Most PHY chips, when idle, can complete a register access in the time
needed for two or three PCI read transactions; bigger delays occur only
when data is currently being moved over the link/PHY interface.  So if
we busy-wait a few times when waiting for the register access to finish,
it is likely that we can finish without having to sleep.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
2010-06-10 08:22:07 +02:00
Stefan Richter
f9c70f9129 firewire: core: trivial fix for warning strings
WARN's format string argument should not carry a printk level prefix.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-09 19:42:18 +02:00
Clemens Ladisch
a10c0ce760 firewire: check cdev response length
Add a check that the data length in the SEND_RESPONSE ioctl is correct.
Incidentally, this also fixes the previously wrong response length of
software-handled lock requests.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-09 19:42:18 +02:00
Clemens Ladisch
262444eecc firewire: ohci: add MSI support
This patch adds support for message-signaled interrupts.

Any native PCI-Express OHCI controller should support MSI, but most are
just PCI cores behind a PCI-E/PCI bridge.  The only chips that are known
to claim to support MSI are the Lucent/Agere/LSI FW643 and the VIA
VT6315, none of which I have been able to test.

Due to the high level of trust I have in the competence of these and any
future chip makers, I thought it a good idea to add a disable-MSI quirk.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

Tested Agere FW643 rev 07 [11c1:5901] and JMicron JMB381 [197b:2380].
Added a quirks list entry for JMB38X since it kept its count of MSI
events consistently at zero.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-09 19:42:18 +02:00
Stefan Richter
148c7866c3 firewire: ohci: do not enable interrupts without the handler
On 26 Apr 2010, Clemens Ladisch wrote:
> In theory, none of the interrupts should occur before the link is
> enabled.  In practice, I'd rather make sure to not set the master
> interrupt enable bit until we have installed the interrupt handler.

and proposed to move OHCI1394_masterIntEnable out of the present
reg_write() into a new one before the HCControl.linkEnable reg_write().

Why not defer setting /all/ of the bits until right before linkEnable?

Reviewed-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-09 19:42:18 +02:00
Stefan Richter
1038953674 firewire: core: check for 1394a compliant IRM, fix inaccessibility of Sony camcorder
Per IEEE 1394 clause 8.4.2.3, a contender for the IRM role shall check
whether the current IRM complies to 1394a-2000 or later.  If not force a
compliant node (e.g. itself) to become IRM.  This was implemented in the
older ieee1394 driver but not yet in firewire-core.

An older Sony camcorder (Sony DCR-TRV25) which implements 1394-1995 IRM
but neither 1394a-2000 IRM nor BM was now found to cause an
interoperability bug:
  - Camcorder becomes root node when plugged in, hence gets IRM role.
  - firewire-core successfully contends for BM role, proceeds to perform
    gap count optimization and resets the bus.
  - Sony camcorder ignores presence of a BM (against the spec, this is
    a firmware bug), performs its idea of gap count optimization and
    resets the bus.
  - Preceding two steps are repeated endlessly, bus never settles,
    regular I/O is practically impossible.
http://thread.gmane.org/gmane.linux.kernel.firewire.user/3913

This is an interoperability regression from the old to the new drivers.
Fix it indirectly by adding the 1394a IRM check.  The spec suggests
three and a half methods to determine 1394a compliance of a remote IRM;
we choose the method of testing the Config_ROM.Bus_Info.generation
field.  This is data that firewire-core should have readily available at
this point, i.e. does not require extra I/O.

Reported-by: Clemens Ladisch <clemens@ladisch.de> (missing 1394a check)
Reported-by: H. S. <hs.samix@gmail.com> (issue with Sony DCR-TRV25)
Tested-by: H. S. <hs.samix@gmail.com>

Cc: <stable@kernel.org> # .32.x and newer

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-06-02 19:48:13 +02:00
Linus Torvalds
55ddf14b04 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  ieee1394: schedule for removal
  firewire: core: use separate timeout for each transaction
  firewire: core: Fix tlabel exhaustion problem
  firewire: core: make transaction label allocation more robust
  firewire: core: clean up config ROM related defined constants
  ieee1394: mark char device files as not seekable
  firewire: cdev: mark char device files as not seekable
  firewire: ohci: cleanups and fix for nonstandard build without debug facility
  firewire: ohci: wait for PHY register accesses to complete
  firewire: ohci: fix up configuration of TI chips
  firewire: ohci: enable 1394a enhancements
  firewire: ohci: do not clear PHY interrupt status inadvertently
  firewire: ohci: add a function for reading PHY registers

Trivial conflicts in Documentation/feature-removal-schedule.txt
2010-05-27 10:22:06 -07:00
Linus Torvalds
f39d01be4c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits)
  vlynq: make whole Kconfig-menu dependant on architecture
  add descriptive comment for TIF_MEMDIE task flag declaration.
  EEPROM: max6875: Header file cleanup
  EEPROM: 93cx6: Header file cleanup
  EEPROM: Header file cleanup
  agp: use NULL instead of 0 when pointer is needed
  rtc-v3020: make bitfield unsigned
  PCI: make bitfield unsigned
  jbd2: use NULL instead of 0 when pointer is needed
  cciss: fix shadows sparse warning
  doc: inode uses a mutex instead of a semaphore.
  uml: i386: Avoid redefinition of NR_syscalls
  fix "seperate" typos in comments
  cocbalt_lcdfb: correct sections
  doc: Change urls for sparse
  Powerpc: wii: Fix typo in comment
  i2o: cleanup some exit paths
  Documentation/: it's -> its where appropriate
  UML: Fix compiler warning due to missing task_struct declaration
  UML: add kernel.h include to signal.c
  ...
2010-05-20 09:20:59 -07:00
Clemens Ladisch
5c40cbfefa firewire: core: use separate timeout for each transaction
Using a single timeout for all transaction that need to be flushed does
not work if the submission of new transactions can defer the timeout
indefinitely into the future.  We need to have timeouts that do not
change due to other transactions; the simplest way to do this is with a
separate timer for each transaction.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (+ one lockdep annotation)
2010-05-19 00:26:30 +02:00
Peter Hurley
753a8970f6 firewire: core: Fix tlabel exhaustion problem
fw_core_handle_response() was not properly clearing tlabel_mask. This
was resulting in premature tlabel exhaustion.

Signed-off-by: Peter Hurley <phurley@charter.net>

This fixes an omission in 2.6.31-rc1 commit 1e626fdc "firewire: core:
use more outbound tlabels" which prevented to really use 64 instead of
32 transaction labels, as soon as split transactions occurred that had
their AR-resp tasklet run after the AT-req tasklet.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-05-19 00:06:47 +02:00
Jiri Kosina
6c9468e9eb Merge branch 'master' into for-next 2010-04-23 02:08:44 +02:00
Linus Torvalds
cfc94b2c9a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: ohci: wait for local CSR lock access to finish
  firewire: ohci: prevent aliasing of locally handled register addresses
  firewire: core: fw_iso_resource_manage: return -EBUSY when out of resources
  firewire: core: fix retries calculation in iso manage_channel()
  firewire: cdev: fix cut+paste mistake in disclaimer
2010-04-22 12:54:54 -07:00
Clemens Ladisch
7906054f0d firewire: core: make transaction label allocation more robust
If one request is so long-lived that it does not get a response before
the following 63 requests, its bit in tlabel_mask is still set when the
next request tries to allocate a transaction label for that number.  In
this state, while the first request is not completed or timed out, no
new requests can be submitted.

To fix this, skip over any label still in use, and do not error out
unless we have entirely run out of labels.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-19 20:00:44 +02:00
Stefan Richter
edd5bdaf12 firewire: core: clean up config ROM related defined constants
Clemens Ladisch pointed out that
  - BIB_IMC is not named like the field is called in the standard,
  - readers of the code may get worried about the magic 0x0c0083c0,
  - a CSR_NODE_CAPABILITIES key is there in the header but not put to
    good use.

So let's rename BIB_IMC, add a defined constant for Node_Capabilities
and a comment which reassures people that somebody thought about it and
they don't have to (or if they still do, tell them where they have to
look for confirmation), and prune our incomplete and arbitrary set of
defined constants of CSR key IDs.  And there is a nother magic number,
that of Bus_Information_Block.Bus_Name, to be defined and commented.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-19 20:00:44 +02:00
Clemens Ladisch
e1393667be firewire: ohci: wait for local CSR lock access to finish
Add a loop to wait for the controller to finish a locally-initiated CSR
lock operation.  Google shows some occurrences of the "swap not done
yet" message which might indicate that some OHCI controllers are not
fast enough to do the lock/swap in the time needed for one PCI access.

This also correctly handles the case where the lock operation did not
finish, instead of silently returning an uninitialized value.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-19 19:58:32 +02:00
Clemens Ladisch
2608203daf firewire: ohci: prevent aliasing of locally handled register addresses
We must compute the offset from the CSR register base with the
full 48 address bits to prevent matching with addresses whose
lower 32 bits happen to be equal with one of the specially
handled registers.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-19 19:58:32 +02:00
Clemens Ladisch
d6372b6e7c firewire: core: fw_iso_resource_manage: return -EBUSY when out of resources
Returning -EIO for all errors would not allow clients to determine if
the resource allocation process itself failed, or if the resources are
not available.  (The latter information is needed by CMP to synchronize
restoring of overlayed connections after a bus reset.)

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-19 19:58:32 +02:00
Clemens Ladisch
3a1f0a0e3d firewire: core: fix retries calculation in iso manage_channel()
If there is a permanent error condition when communicating with the IRM,
after the sixth error, the retry variable will be decremented to -1.
If, in this case, the bits in channels_mask are not yet exhausted, the
next channel is retried 2^32 times.

To fix this, check that retry is never decremented beyond zero.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-19 19:58:32 +02:00
Linus Torvalds
2fed94c032 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: cdev: change license of exported header files to MIT license
  firewire: cdev: comment fixlet
  firewire: cdev: iso packet documentation
  firewire: cdev: fix information leak
  firewire: cdev: require quadlet-aligned headers for transmit packets
  firewire: cdev: disallow receive packets without header
2010-04-15 11:56:20 -07:00
Stefan Richter
3ac26b2ee3 firewire: cdev: mark char device files as not seekable
The <linux/firewire-cdev.h> character device file ABI (i.e. /dev/fw*
character device file interface) does not make any use of lseek(),
pread(), pwrite() (or any kind of write() at all).

Use nonseekable_open() and, redundantly, set file_operations.llseek to
no_llseek to remove any doubt whether the BKL-grabbing default_llseek
handler is used.  (Also shuffle file_operations initialization according
to the order of handler definitions.)

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10 16:51:14 +02:00
Stefan Richter
5da3dac8d9 firewire: ohci: cleanups and fix for nonstandard build without debug facility
1) Clean up two function names:  The ohci_ prefix is only used in names
of fw_card_driver hooks.  There were two unnecessary exceptions.

2) Replace empty macros by empty inline functions so that call parameter
type checking is available in #ifndef'd builds.

3) CONFIG_FIREWIRE_OHCI_DEBUG is currently a hidden kconfig variable,
hence is not going to be switched off by anybody.  Still, it can be
switched off but then compilation will fail in ohci_enable() at the
expression param_debug & OHCI_PARAM_DEBUG_BUSRESETS.  Add the necessary
definitions in the nonstandard case.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10 16:51:14 +02:00
Stefan Richter
35d999b120 firewire: ohci: wait for PHY register accesses to complete
Rather than having the arbitrary msleep(2) pause, let read_phy_reg()
loop until the link--phy access was finished.

Factor write_phy_reg() out of ohci_update_phy_reg() and of
read_paged_phy_reg() and let it loop too until the link--phy access was
finished.

Like in the older ohci1394 driver, a timeout of 100 milliseconds is
chosen.  Unlike the old driver, we sleep instead of busy-wait in each
waiting loop iteration.  Instead of a loop, the waiting could probably
also be implemented interrupt driven, but why bother.  It would require
up and running interrupt handling before the link was fully configured
and enabled.

Also modify functions a bit:  Error return and value return can be
combined in read_phy_reg() since the domain of values is only u8.
Likewise in read_paged_phy_reg().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-04-10 16:51:14 +02:00