For assigning sysfs entries for a card device from the driver,
introduce a new helper function, snd_card_add_dev_attr().  In this
way, we can avoid the possible race between the device registration
and the sysfs addition / removal.

The driver can pass a new attribute group to add freely.  This has to
be called before snd_card_register().

Currently, up to two extra groups can be added.  More than that, it'll
return an error.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Introduce a new helper function snd_device_initialize() to initialize
the device object for sound devices.
Reviewed-by: NJaroslav Kysela <perex@perex.cz>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Some functions missed the proper kerneldoc comments.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The user-control put and get handlers as well as the tlv do not protect against
concurrent access from multiple threads. Since the state of the control is not
updated atomically it is possible that either two write operations or a write
and a read operation race against each other. Both can lead to arbitrary memory
disclosure. This patch introduces a new lock that protects user-controls from
concurrent access. Since applications typically access controls sequentially
than in parallel a single lock per card should be fine.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Acked-by: NJaroslav Kysela <perex@perex.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

A few code cleanups and optimizations.  In addition, drop
snd_device_disconnect() that isn't used at all, and drop the return
values from snd_device_free*().

Another slight difference by this change is that now the device state
will become always SNDRV_DEV_REGISTERED no matter whether dev_register
ops is present or not.  It's for better consistency.  There should be
no impact for the current tree, as the state isn't checked.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Basically, the device type specifies the priority of the device to be
registered / freed, too.  However, the priority value isn't well
utilized but only it's checked as a group.  This results in
inconsistent register and free order (where each of them should be in
reversed direction).

This patch simplifies the device list management code by simply
inserting a list entry at creation time in an incremental order for
the priority value.  Since we can just follow the link for register,
disconnect and free calls, we don't have to specify the group; so the
whole enum definitions are also simplified as well.

The visible change to outside is that the priorities of some object
types are revisited.  For example, now the SNDRV_DEV_LOWLEVEL object
is registered before others (control, PCM, etc) and, in return,
released after others.  Similarly, SNDRV_DEV_CODEC is in a lower
priority than SNDRV_DEV_BUS for ensuring the dependency.

Also, the unused SNDRV_DEV_TOPLEVEL, SNDRV_DEV_LOWLEVEL_PRE and
SNDRV_DEV_LOWLEVEL_NORMAL are removed as a cleanup.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

While moving the card device into struct snd_card, the reference to
the assigned card in sysfs show/store callbacks were forgotten to be
refreshed, still accessing to the no longer used drvdata.  Fix these
places to refer correctly via container_of().

Also, remove the superfluous NULL checks since it's guaranteed to be
non-NULL now.

Fixes: 8bfb181c ('ALSA: Embed card device into struct snd_card')
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Use dev_err() & co as much as possible.  If not available (no device
assigned at the calling point), use pr_xxx() helpers instead.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Drop the own refcount but use the standard device refcounting via
get_device() and put_device().  Introduce a new completion to snd_card
instead of the wait queue for syncing the last release, which is used
in snd_card_free().
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

... instead of calling device_create_file() manually.
No functional change.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

As prepared in the previous patch, we are ready to create a device
struct for the card object in snd_card_create() now.  This patch
changes the scheme from the old style to:

- embed a device struct for the card object into snd_card struct,
- initialize the card device in snd_card_create() (but not register),
- registration is done in snd_card_register() via device_add()

The actual card device is stored in card->card_dev.  The card->dev
pointer is kept unchanged and pointing to the parent device as before
for compatibility reason.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This is a part of preliminary works for modernizing the ALSA device
structure.  So far, we set card->dev at later point after the object
creation.  Because of this, the core layer doesn't always know which
device is being handled before it's actually registered, and it makes
impossible to show the device in error messages, for example.  The
first goal is to achieve a proper struct device initialization at the
very beginning of probing.

As a first step, this patch introduces snd_card_new() function (yes
there was the same named function in the very past), in order to
receive the parent device pointer from the very beginning.
snd_card_create() is marked as deprecated.

At this point, there is no functional change other than that.  The
actual change of the device creation scheme will follow later.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Replace the lengthy #if defined(XXX) || defined(XXX_MODULE) with the
new IS_ENABLED() macro.

The patch still doesn't cover all ifdefs.  For example, the dependency
on CONFIG_GAMEPORT is still open-coded because this also has an extra
dependency on MODULE.  Similarly, an open-coded ifdef in pcm_oss.c and
some sequencer-related stuff are left untouched.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

There are two loops that are almost identical but only with different
checks.  Refactor them with a simple helper, and give a bit more
comments what's doing there.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The test here is intended intended to prevent shift wrapping bugs when
we do "1U << idx2".  We should consider the number of bits in a u32
instead of the number of bytes.

[fix another chunk similarly by tiwai]

Fixes: 7bb2491b ('ALSA: Add kconfig to specify the max card numbers')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

When no proper id string is given, the driver tries to fall back to
copy the proc_root name string via strcpy(), but this might overflow
the fixed string size.  Let's use strlcpy().

Spotted by coverity CID 139008.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

module->name is a fixed array, so we can check the empty contents
straightforwardly in module_slot_match().

Spotted by coverity CID 1056786.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Currently ALSA supports up to 32 card instances when the dynamic minor
is used.  While 32 cards are usually big enough for normal use cases,
there are sometimes weird requirements with more card support.

Actually, this limitation, 32, comes from the index option, where you
can pass the bit mask to assign the card.  Other than that, we can
actually give more cards up to the minor number limits (currently 256,
which can be extended more, too).

This patch adds a new Kconfig to specify the max card numbers, and
changes a few places to accept more than 32 cards.

The only incompatibility with high card numbers would be the handling
of index option.  The index option can be still used to pass the
bitmask for card assignments, but this works only up to 32 slots.
More than 32, no bitmask style option is available but only a single
slot can be specified via index option.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

ALSA core tries to add a suffix as "_1" automatically when the given
id string conflicts.  The current code assumes implicitly that the max
card number is 16 so that the single hex "_X" suffix can be put.
However, with the dynamic device management, the card can be at most
32, so it can put even a non-hex character there.  Also, when the max
card number is increased in future, this would result in worse.

This patch rewrites the code to add the suffix string in a simpler
(thus cleaner) way.  It can support up to three digits, so it should
suffice for most requirements.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

script/kernel-doc reports the following type of warnings (when run in verbose
mode):

Warning(sound/core/init.c:152): No description found for return value of
'snd_card_create'

To fix that:
- add missing descriptions of function return values
- use "Return:" sections to describe those return values

Along the way:
- complete some descriptions
- fix some typos
Signed-off-by: NYacine Belkadi <yacine.belkadi.1@gmail.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

For more strict protection for wild disconnections, a refcount is
introduced to the card instance, and let it up/down when an object is
referred via snd_lookup_*() in the open ops.

The free-after-last-close check is also changed to check this refcount
instead of the empty list, too.
Reported-by: NMatthieu CASTET <matthieu.castet@parrot.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

For files that are actively using linux/device.h, make sure
that they call it out.  This will allow us to clean up some
of the implicit uses of linux/device.h within include/*
without introducing build regressions.

Yes, this was created by "cheating" -- i.e. the headers were
cleaned up, and then the fallout was found and fixed, and then
the two commits were reordered.  This ensures we don't introduce
build regressions into the git history.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

The code to handle the card id string is fairly messy, so here is a
tidy up.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Lots of sound drivers were getting module.h via the implicit presence
of it in <linux/device.h> but we are going to clean that up.  So
fix up those users now.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Drop a few variables that are never read.
Signed-off-by: NLuca Tettamanti <kronos.it@gmail.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The card-id parser assigns the string "default" when no appropriate word
is found in the card name.  But this string may confuse the alsa-lib, so
better to avoid.  Use "Default" now instead.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This patch fixes a race between snd_card_file_remove() and
snd_card_disconnect().  When the card is added to shutdown_files list
in snd_card_disconnect(), but it's freed in snd_card_file_remove() at
the same time, the shutdown_files list gets corrupted.  The list member
must be freed in snd_card_file_remove() as well.
Reported-and-tested-by: NRuss Dill <russ.dill@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

"gadget", "through", "command", "maintain", "maintain", "controller", "address",
"between", "initiali[zs]e", "instead", "function", "select", "already",
"equal", "access", "management", "hierarchy", "registration", "interest",
"relative", "memory", "offset", "already",
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

This patch removes the old CONFIG_SYSFS_DEPRECATED_V2 config option,
but it keeps the logic around to handle block devices in the old manner
as some people like to run new kernel versions on old (pre 2007/2008)
distros.
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: "James E.J. Bottomley" <James.Bottomley@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When user want to change the card id to the same string
on the card via /sys/class/sound/cardX/id, do not
report error. Instead return with success without
doing anything.
Signed-off-by: NPeter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The struct snd_monitor_file is used locally only in sound/core/init.c,
thus it should be moved there from the public sound/core.h.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Move locking outside snd_card_set_id_internal() function and rename it
to snd_card_set_id_no_lock() for better function description.

User defined id is just copied to card structure at allocation time.
The real unique id procedure is called in snd_card_register() to
ensure real atomicity.
Signed-off-by: NJaroslav Kysela <perex@perex.cz>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The introduction of snd_card_set_id() added a lock on the card list
to the old choose_default_id() function when using it to implement
the new API call. This lock is needed to allow us to walk the list
and check to see if our new name is a duplicate. Unfortunately this
causes a lockup when called from snd_card_register() (in cases
where no ID is supplied for the card) since the card list is already
locked there.

Fix this fairly hideously by factoring out the implementation and
using a flag to indicate if the lock should be held. A better fix
would probably be to refactor snd_card_register() to move the
_set_id() outside the locking region but I can't immediately see
anything I can convince myself is safe.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Introduce snd_card_set_id() function to allow lowlevel drivers to set
default identification name for card slot. The function checks also
for identification name collisions and tries to create unique name.

Also, the snd_card_create() function is simplified, because this new
function is used. As bonus, proper name collision checks are evaluated
at the card create time.
Signed-off-by: NJaroslav Kysela <perex@perex.cz>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Use the standard linked list for snd_monitor_file management.
Also, move the list deletion of shutdown_list element into
snd_disconnect_release() (for simplification).
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Introduced snd_card_create() function as a replacement of snd_card_new().
The new function returns a negative error code so that the probe callback
can return the proper error code, while snd_card_new() can give only NULL
check.

The old snd_card_new() is still provided as an inline function but with
__deprecated attribute.  It'll be removed soon later.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Do not ignore the return of 'device_create_file' in
'snd_card_register' and thereby fixing the following warnings:

sound/core/init.c: In function 'snd_card_register':
sound/core/init.c:640: warning: ignoring return value of
'device_create_file', declared with attribute warn_unused_result
sound/core/init.c:641: warning: ignoring return value of
'device_create_file', declared with attribute warn_unused_result
Signed-off-by: NHannes Eder <hannes@hanneseder.net>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Signed-off-by: NJaroslav Kysela <perex@perex.cz>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

For udev, we need a way to rename soundcard names. The soundcard numbers
(indexes) are hardwired but we have a text identification which can be
changed at run-time. The ALSA user space tools already allow using of
this text identification.
Signed-off-by: NJaroslav Kysela <perex@perex.cz>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

As it is, all instances of ->release() for files that have ->fasync()
need to remember to evict file from fasync lists; forgetting that
creates a hole and we actually have a bunch that *does* forget.

So let's keep our lives simple - let __fput() check FASYNC in
file->f_flags and call ->fasync() there if it's been set.  And lose that
crap in ->release() instances - leaving it there is still valid, but we
don't have to bother anymore.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>