When a monitor stream is active, the next PCM stream access results in
EBUSY error because of the check in line6_stream_start().  Fix this by
just skipping the submission of pending URBs when the stream is
already running instead.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=101431
Cc: <stable@vger.kernel.org> # v4.0+
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Both playback and capture callbacks are identical, so let's merge
them.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The current code deals with the stream start / stop solely via
line6_pcm_acquire() and line6_pcm_release().  This was (supposedly)
intended to avoid the races, but it doesn't work as expected.  The
concurrent acquire and release calls can be performed without proper
protections, thus this might result in memory corruption.
Furthermore, we can't take a mutex to protect the whole function
because it can be called from the PCM trigger callback that is an
atomic context.  Also spinlock isn't appropriate because the function
allocates with kmalloc with GFP_KERNEL.  That is, these function just
lead to singular problems.

This is an attempt to reduce the existing races.  First off, separate
both the stream buffer management and the stream URB management.  The
former is protected via a newly introduced state_mutex while the
latter is protected via each line6_pcm_stream lock.

Secondly, the stream state are now managed in opened and running bit
flags of each line6_pcm_stream.  Not only this a bit clearer than
previous combined bit flags, this also gives a better abstraction.
These rewrites allows us to make common hw_params and hw_free
callbacks for both playback and capture directions.

For the monitor and impulse operations, still line6_pcm_acquire() and
line6_pcm_release() are used.  They call internally the corresponding
functions for both playback and capture streams with proper lock or
mutex.  Unlike the previous versions, these function don't take the
bit masks but the only single type value.  Also they are supposed to
be applied only as duplex operations.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Clearing prev_fsize in line6_pcm_acquire() is pretty racy.
This can be called at any time while the stream is being played.
Rather better to clear prev_fbuf and prev_fsize at the proper place
like the stream stop for capture, and just after copying the monitor /
impulse data inside the spinlock.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The PCM stream buffer allocation and free are identical for both
playback and capture streams.  Provide single helper functions.
These are used only in pcm.c, thus they can be even static.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This is the last remaining snd_printk() usage in this driver.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The codes to unlink and sync URBs are identical for both playback and
capture streams.  Consolidate to single helper functions.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Introduce a new line6_pcm_stream structure and group individual
fields of snd_line6_pcm struct to playback and capture groups.

This patch itself just does rename and nothing else.  More
meaningful cleanups based on these fields shuffling will follow.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Using a decremental loop without particular reasons worsens the
readability a lot.  Use incremental loops instead.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The trigger callback is already spinlocked, so we need no more lock
here (even for the linked substreams).  Let's drop it.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

line6_pcm_acquire() tries to restore the newly obtained resources at
the error path.  But some flags aren't recorded and released properly
when the corresponding buffer is already present.  These bits have to
be cleared in the error recovery, too.

Also, "flags_final" can be initialized to zero since we pass only the
subset of "channels" bits.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Fixed a few places using bits OR wrongly for condition checks.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The driver version string was removed in an ealier commit for being
useless.  These are equally useless.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The correct spelling includes the space.  Fix this in strings and
comments that refer to the manufacturer.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Call line6_pcm_disconnect() at disconnect to make sure that all URBs
are cleared.  Also reduce the superfluous snd_pcm_stop() calls from
the function (and remove the unused function) since the streams are
guaranteed to be stopped at this point via snd_card_disconnect().
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Such a debug is needed in the core code, not in each lowlevel driver.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This is a fairly big rewrite regarding the card resource management in
line6 drivers:

- The card creation is moved into line6_probe().  This adds the global
  destructor to private_free, so that each driver doesn't have to call
  it any longer.

- The USB disconnect callback handles the card release, thus each
  driver needs to concentrate on only its own resources.  No need to
  snd_card_*() call in the destructor.

- Fix the potential stall in disconnection by removing
  snd_card_free().   It's replaced with snd_card_free_when_closed()
  for asynchronous release.

- The only remaining operation for the card in each driver is the call
  of snd_card_register().  All the rest are dealt in the common module
  by itself.

- These ended up with removal of audio.[ch] as a result of a reduction
  of one layer.  Each driver just needs to call line6_probe().
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The PCM trigger callback is guaranteed to be called already in
spinlock / irq-disabled context.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Otherwise it oopses.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Instead of handling the card-specific resource in snd_device, attach
it into pcm->private_data and release it directly in private_free.
This simplifies the code and structure.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Instead of sysfs and the conditional build with Kconfig, implement the
handling of the impulse response controls via control API, and always
enable the build.  Two new controls, "Impulse Response Volume" and
"Impulse Response Period" are added as a replacement for the former
sysfs files.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Split to each individual driver for POD, PODHD, TonePort and Variax
with a core LINE6 helper module.  The new modules follow the standard
ALSA naming rule with snd prefix: snd-usb-pod, snd-usb-podhd,
snd-usb-toneport and snd-usb-variax, together with the corresponding
CONFIG_SND_USB_* Kconfig items.
Tested-by: NChris Rorvick <chris@rorvick.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Promote line6 driver from staging to sound/usb/line6 directory, and
maintain through sound subsystem tree.

This commit just moves the code and adapts Makefile / Kconfig.
The further renames and misc cleanups will follow.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The device type can now be used to determine the addresses of the
audio endpoints for the interface.  Drop the conditional logic and make
these values properties.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Commit 1027f476 (staging: line6: sync with upstream) removed PCM
from the Pocket POD capabilities but left the endpoint configuration.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The driver uses a different altsetting depending on the interface.  Add
device type entries for each of these.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The PODxt Live device has both a POD and a Variax interface.  Add device
type entries for each of these.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Including "BIT" in the macro name is pointless.  Replace with "CAP" to
provide some context for what its value represents.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The driver currently uses the device's idProduct as input to several
switch statements.  In some cases this is not sufficiently granular and
the interface number must be taken into account.

Store the device type in `usb_line6' and key off of it instead.  New
types can then be added that map to specific interfaces on the device so
that this conditional logic can be flattened out.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Support for these devices appears to have never been completed.  Remove
them from the device table along with a minimal amount of supporting
code.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Pass the actual variable to sizeof instead of a type definition.
Signed-off-by: NL. Alberto Giménez <agimenez@sysvalve.es>
Acked-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Also remove superfluous snd_card_set_dev() calls.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This patch adds support for the Line 6 POD HD400 to the line6usb driver.
Signed-off-by: NChris Bajumpaa <cbajumpa@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Move to use the DEVICE_ATTR_RW/RO macros, making it easier to audit the
sysfs file permissions, and get rid of the "empty" callback for
read-only files, saving lines of code.

Cc: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Laurent Navet <laurent.navet@gmail.com>
Cc: Johannes Thumshirn <morbidrsa@googlemail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

snd_pcm_stop() must be called in the PCM substream lock context.

Cc: <stable@vger.kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

__sync_fetch_and_and and __sync_fetch_and_or are functions that are provided
by gcc and depending on the target architecture may be implemented in libgcc,
which is not always available in the kernel. This leads to a build failure
on ARMv5:

drivers/built-in.o: In function `line6_pcm_release':
:(.text+0x3bfe80): undefined reference to `__sync_fetch_and_and_4'
drivers/built-in.o: In function `line6_pcm_acquire':
:(.text+0x3bff30): undefined reference to `__sync_fetch_and_or_4'

To work around this, we can use the kernel-provided cmpxchg macro.

Build-tested only.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Markus Grabner <grabner@icg.tugraz.at>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

alloc failures already get standardized OOM
messages and a dump_stack.

For the affected mallocs around these OOM messages:

Converted kzallocs with multiplies to kcalloc.
Converted kmallocs with multiplies to kmalloc_array.
Converted a kmalloc/strlen/strncpy to kstrdup.
Moved a spin_lock below a removed OOM message and
removed a now unnecessary spin_unlock.
Neatened alignment and whitespace.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

fix those checkpatch issues
drivers/staging/line6/pcm.c:84:
	WARNING: simple_strtoul is obsolete, use kstrtoul instead
	call to obsolete simple_strtoul() replaced by kstrtoint()

drivers/staging/line6/pcm.c:423:
	ERROR: switch and case should be at the same indent
	realigns comments
Signed-off-by: NLaurent Navet <laurent.navet@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>