Add a new helper function snd_pcm_stop_xrun() to the standard sequnce
lock/snd_pcm_stop(XRUN)/unlock by a single call, and replace the
existing open codes with this helper.

The function checks the PCM running state to prevent setting the wrong
state, too, for more safety.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

Also remove superfluous snd_card_set_dev() calls.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Add a flag to snd_fw_transaction() to allow it to abort when a bus reset
happens.  This removes most of the duplicated error handling loops that
were required around calls to the low-level fw_run_transaction().

Also add a flag to suppress error messages; errors are expected when we
attempt to clean up after the device was unplugged.

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

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 <stefanr@s5r6.in-berlin.de>
Acked-by: Clemens Ladisch <clemens@ladisch.de> (for sound/firewire/)
Cc: Peter Hurley <peter@hurleysoftware.com> (for drivers/staging/fwserial/)

Pull IEEE 1394 (FireWire) subsystem updates post v3.3 from Stefan Richter:

 - Some SBP-2 initiator fixes, side product from ongoing work on a target.

 - Reintroduction of an isochronous I/O feature of the older ieee1394 driver
   stack (flush buffer completions); it was evidently rarely used but not
   actually unused.  Matching libraw1394 code is already available.

 - Be sure to prefix all kernel log messages with device name or card name,
   and other logging related cleanups.

 - Misc other small cleanups, among them a small API change that affects
   sound/firewire/ too. Clemens Ladisch is aware of it.

* tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394: (26 commits)
  firewire: allow explicit flushing of iso packet completions
  firewire: prevent dropping of completed iso packet header data
  firewire: ohci: factor out iso completion flushing code
  firewire: ohci: simplify iso header pointer arithmetic
  firewire: ohci: optimize control bit checks
  firewire: ohci: remove unused excess_bytes field
  firewire: ohci: copy_iso_headers(): make comment match the code
  firewire: cdev: fix IR multichannel event documentation
  firewire: ohci: fix too-early completion of IR multichannel buffers
  firewire: ohci: move runtime debug facility out of #ifdef
  firewire: tone down some diagnostic log messages
  firewire: sbp2: replace a GFP_ATOMIC allocation
  firewire: sbp2: Fix SCSI sense data mangling
  firewire: sbp2: Ignore SBP-2 targets on the local node
  firewire: sbp2: Take into account Unit_Unique_ID
  firewire: nosy: Use the macro DMA_BIT_MASK().
  firewire: core: convert AR-req handler lock from _irqsave to _bh
  firewire: core: fix race at address_handler unregistration
  firewire: core: remove obsolete comment
  firewire: core: prefix log messages with card name
  ...

fw_unit device drivers invariably need to talk to the fw_unit's parent
(an fw_device) and grandparent (an fw_card).  firewire-core already
maintains an fw_card reference for the entire lifetime of an fw_device.
Likewise, let firewire-core maintain an fw_device reference for the
entire lifetime of an fw_unit so that fw_unit drivers don't have to.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

Remove a field that is not used at all.  This remained from
earlier tests, but the current driver has decided not to handle
iris notifications.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Since commit 13882a82ee16 (optimize iso queueing by setting
wake only after the last packet), drivers are required to call
fw_iso_context_queue_flush() after queueing a batch of packets.
The missing call would have an effect only if the controller
queue underruns, but then the DMA would stop completely.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Lockdep complains about conflicts between isight->mutex,
ALSA's register_mutex, mm->mmap_sem, and pcm->open_mutex.

This can be fixed by moving the calls to isight_pcm_abort(),
snd_card_disconnect(), and fw_iso_resources_update() out of
isight->mutex.  These functions are designed to be called
asynchronously; the mutex needs to protect only the device
streaming state modified by isight_start/stop_streaming().

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

When aborting a PCM stream, the xrun is signaled only if the stream is
running.  When disconnecting a PCM stream, calling snd_card_disconnect()
too early would change the stream into a non-running state and thus
prevent the xrun from being noticed by user space.

To prevent this, move the snd_card_disconnect() call after the xrun.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>