Commit Graph

131 Commits

Author SHA1 Message Date
Takashi Iwai
ef34a0ae7a ALSA: core: Add async signal helpers
Currently the call of kill_fasync() from an interrupt handler might
lead to potential spin deadlocks, as spotted by syzkaller.
Unfortunately, it's not so trivial to fix this lock chain as it's
involved with the tasklist_lock that is touched in allover places.

As a temporary workaround, this patch provides the way to defer the
async signal notification in a work.  The new helper functions,
snd_fasync_helper() and snd_kill_faync() are replacements for
fasync_helper() and kill_fasync(), respectively.  In addition,
snd_fasync_free() needs to be called at the destructor of the relevant
file object.

Link: https://lore.kernel.org/r/20220728125945.29533-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-07-29 12:57:10 +02:00
Takashi Iwai
c27e1efb61 ALSA: control: Use xarray for faster lookups
The control elements are managed in a single linked list and we
traverse the whole list for matching each numid or ctl id per every
inquiry of a control element.  This is OK-ish for a small number of
elements but obviously it doesn't scale.  Especially the matching with
the ctl id takes time because it checks each field of the snd_ctl_id
element, e.g. the name string is matched with strcmp().

This patch adds the hash tables with Xarray for improving the lookup
speed of a control element.  There are two xarray tables added to the
card; one for numid and another for ctl id.  For the numid, we use the
numid as the index, while for the ctl id, we calculate a hash key.

The lookup is done via a single xa_load() execution.  As long as the
given control element is found on the Xarray table, that's fine, we
can give back a quick lookup result.  The problem is when no entry
hits on the table, and for this case, we have a slight optimization.
Namely, the driver checks whether we had a collision on Xarray table,
and do a fallback search (linear lookup of the full entries) only if a
hash key collision happened beforehand.
So, in theory, the inquiry for a non-existing element might take still
time even with this patch in a worst case, but this must be pretty
rare.

The feature is enabled via CONFIG_SND_CTL_FAST_LOOKUP, which is turned
on as default.  For simplicity, the option can be turned off only when
CONFIG_EXPERT is set ("You are expert? Then you manage 1000 knobs").

Link: https://lore.kernel.org/r/20211028130027.18764-1-tiwai@suse.de
Link: https://lore.kernel.org/r/20220609180504.775-1-tiwai@suse.de
Link: https://lore.kernel.org/all/cover.1653813866.git.quic_rbankapu@quicinc.com/
Link: https://lore.kernel.org/r/20220610064537.18660-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-06-15 07:44:55 +02:00
Takashi Iwai
fee2b871d8 ALSA: core: Add snd_card_free_on_error() helper
This is a small helper function to handle the error path more easily
when an error happens during the probe for the device with the
device-managed card.  Since devres releases in the reverser order of
the creations, usually snd_card_free() gets called at the last in the
probe error path unless it already reached snd_card_register() calls.
Due to this nature, when a driver expects the resource releases in
card->private_free, this might be called too lately.

As a workaround, one should call the probe like:

 static int __some_probe(...) { // do real probe.... }

 static int some_probe(...)
 {
	return snd_card_free_on_error(dev, __some_probe(dev, ...));
 }

so that the snd_card_free() is called explicitly at the beginning of
the error path from the probe.

This function will be used in the upcoming fixes to address the
regressions by devres usages.

Fixes: e8ad415b7a ("ALSA: core: Add managed card creation")
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220412093141.8008-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2022-04-12 11:47:57 +02:00
Takashi Iwai
c2b94954ad ALSA: core: Add device-managed request_dma()
This patch adds a devres-supported helper for requesting an ISA DMA
channel that will be automatically freed at the device unbinding.
It'll be used by quite a few ISA sound drivers.

Link: https://lore.kernel.org/r/20210715075941.23332-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-07-19 16:16:34 +02:00
Takashi Iwai
e8ad415b7a ALSA: core: Add managed card creation
As a second step for preliminary to widen the devres usages among
sound drivers, this patch adds a new ALSA core API function,
snd_devm_card_new(), to create a snd_card object via devres.
When a card object is created by this new function, snd_card_free() is
called automatically and the card object resource gets released at the
device unbinding time.

However, the story isn't that simple.  A caveat is that we have to
call snd_card_free() at the very first of the whole resource release
procedure, in order to assure that the all exposed devices on
user-space are deleted and sync with processes accessing those devices
before releasing resources.

For achieving it, snd_card_register() adds a new devres action to
trigger snd_card_free() automatically when the given card object is a
"managed" one.  Since usually snd_card_register() is the last step of
the initialization, this should work in most cases.

With all these tricks, some drivers can get rid of the whole driver
remove callback code.

About a bit of implementation details: the patch adds two new flags to
snd_card object: managed and releasing.  The former indicates that the
object was created via snd_devm_card_new(), and the latter is used for
avoiding the double-free of snd_card_free() calls.  Both flags are
fairly internal and likely uninteresting to normal users.

Link: https://lore.kernel.org/r/20210715075941.23332-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-07-19 16:16:33 +02:00
Takashi Iwai
b6cc78da36 ALSA: Drop superfluous argument from snd_power_wait()
The power_state argument of snd_power_wait() is superfluous, receiving
only SNDRV_POWER_STATE_D0.  Let's drop it in all callers for
simplicity.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210523090920.15345-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-05-25 08:49:39 +02:00
Takashi Iwai
e94fdbd7b2 ALSA: control: Track in-flight control read/write/tlv accesses
Although the power state check is performed in various places (e.g. at
the entrance of quite a few ioctls), there can be still some pending
tasks that already went into the ioctl handler or other ops, and those
may access the hardware even after the power state check.  For
example, kcontrol access ioctl paths that call info/get/put callbacks
may update the hardware registers.  If a system wants to assure the
free from such hw access (like the case of PCI rescan feature we're
going to implement in future), this situation must be avoided, and we
have to sync such in-flight tasks finishing beforehand.

For that purpose, this patch introduces a few new things in core code:
- A refcount, power_ref, and a wait queue, power_ref_sleep, to the
  card object
- A few new helpers, snd_power_ref(), snd_power_unref(),
  snd_power_ref_and_wait(), and snd_power_sync_ref()

In the code paths that call kctl info/read/write/tlv ops, we check the
power state with the newly introduced snd_power_ref_and_wait().  This
function also takes the card.power_ref refcount for tracking this
in-flight task.  Once after the access finishes, snd_power_unref() is
called to released the refcount in return.  So the driver can sync via
snd_power_sync_ref() assuring that all in-flight tasks have been
finished.

As of this patch, snd_power_sync_ref() is called only at
snd_card_disconnect(), but it'll be used in other places in future.

Note that atomic_t is used for power_ref intentionally instead of
refcount_t.  It's because of the design of refcount_t type; refcount_t
cannot be zero-based, and it cannot do dec_and_test() call for
multiple times, hence it's not suitable for our purpose.

Also, this patch changes snd_power_wait() to accept only
SNDRV_CTL_POWER_D0, which is the only value that makes sense.
In later patch, the snd_power_wait() calls will be cleaned up.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210523090920.15345-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-05-25 08:48:28 +02:00
Takashi Iwai
533a7ed9d5 ALSA: core: Use READ_ONCE() / WRITE_ONCE() for power state change
We need proper barriers to handle the power state change of the card
from different CPUs.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20210523090920.15345-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-05-25 08:48:03 +02:00
Takashi Sakamoto
66c6d1ef86 ALSA: control: Add memory consumption limit to user controls
ALSA control interface allows users to add arbitrary control elements
(called "user controls" or "user elements"), and its resource usage is
limited just by the max number of control sets (currently 32).  This
limit, however, is quite loose: each allocation of control set may
have 1028 elements, and each element may have up to 512 bytes (ILP32) or
1024 bytes (LP64) of value data. Moreover, each control set may contain
the enum strings and TLV data, which can be up to 64kB and 128kB,
respectively.  Totally, the whole memory consumption may go over 38MB --
it's quite large, and we'd rather like to reduce the size.

OTOH, there have been other requests even to increase the max number
of user elements; e.g. ALSA firewire stack require the more user
controls, hence we want to raise the bar, too.

For satisfying both requirements, this patch changes the management of
user controls: instead of setting the upper limit of the number of
user controls, we check the actual memory allocation size and set the
upper limit of the total allocation in bytes.  As long as the memory
consumption stays below the limit, more user controls are allowed than
the current limit 32. At the same time, we set the lower limit (8MB)
as default than the current theoretical limit, in order to lower the
risk of DoS.

As a compromise for lowering the default limit, now the actual memory
limit is defined as a module option, 'max_user_ctl_alloc_size', so that
user can increase/decrease the limit if really needed, too.

Link: https://lore.kernel.org/r/s5htur3zl5e.wl-tiwai@suse.de
Co-developed-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Tested-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210408103149.40357-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-04-08 13:31:03 +02:00
Hui Wang
2d670ea2bd ALSA: jack: implement software jack injection via debugfs
This change adds audio jack injection feature through debugfs, with
this feature, we could validate alsa userspace changes by injecting
plugin or plugout events to the non-phantom audio jacks.

With this change, the sound core will build the folders
$debugfs_mount_dir/sound/cardN if SND_DEBUG and DEBUG_FS are enabled.
And if users also enable the SND_JACK_INJECTION_DEBUG, the jack
injection nodes will be built in the folder cardN like below:

$tree $debugfs_mount_dir/sound
$debugfs_mount_dir/sound
├── card0
│   ├── HDMI_DP_pcm_10_Jack
│   │   ├── jackin_inject
│   │   ├── kctl_id
│   │   ├── mask_bits
│   │   ├── status
│   │   ├── sw_inject_enable
│   │   └── type
...
│   └── HDMI_DP_pcm_9_Jack
│       ├── jackin_inject
│       ├── kctl_id
│       ├── mask_bits
│       ├── status
│       ├── sw_inject_enable
│       └── type
└── card1
    ├── HDMI_DP_pcm_5_Jack
    │   ├── jackin_inject
    │   ├── kctl_id
    │   ├── mask_bits
    │   ├── status
    │   ├── sw_inject_enable
    │   └── type
    ...
    ├── Headphone_Jack
    │   ├── jackin_inject
    │   ├── kctl_id
    │   ├── mask_bits
    │   ├── status
    │   ├── sw_inject_enable
    │   └── type
    └── Headset_Mic_Jack
        ├── jackin_inject
        ├── kctl_id
        ├── mask_bits
        ├── status
        ├── sw_inject_enable
        └── type

The nodes kctl_id, mask_bits, status and type are read-only, users
could check jack or jack_kctl's information through them.

The nodes sw_inject_enable and jackin_inject are directly used for
injection. The sw_inject_enable is read-write, users could check if
software injection is enabled or not on this jack, and users could
echo 1 or 0 to enable or disable software injection on this jack. Once
the injection is enabled, the jack will not change by hardware events
anymore, once the injection is disabled, the jack will restore the
last reported hardware events to the jack. The jackin_inject is
write-only, if the injection is enabled, users could echo 1 or 0 to
this node to inject plugin or plugout events to this jack.

For the detailed usage information on these nodes, please refer to
Documentation/sound/designs/jack-injection.rst.

Reviewed-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://lore.kernel.org/r/20210127085639.74954-2-hui.wang@canonical.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2021-02-02 10:37:07 +01:00
Mauro Carvalho Chehab
f7b6603c66 ALSA: fix kernel-doc markups
Kernel-doc markups should use this format:
        identifier - description

There is a common comment marked, instead, with kernel-doc
notation.

Some identifiers have different names between their prototypes
and the kernel-doc markup.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/535182d6f55d7a7de293dda9676df68f5f60afc6.1603469755.git.mchehab+huawei@kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-10-26 15:26:31 +01:00
Takashi Iwai
c208a53350 ALSA: core: Add snd_device_get_state() helper
A new small helper to get the current state of the device registration
for the given object.  It'll be used for USB-audio driver to check the
delayed device registrations.

Link: https://lore.kernel.org/r/20200323170643.19181-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-03-23 18:09:19 +01:00
Takashi Iwai
d4cfb30fce ALSA: pcm: Set per-card upper limit of PCM buffer allocations
Currently, the available buffer allocation size for a PCM stream
depends on the preallocated size; when a buffer has been preallocated,
the max buffer size is set to that size, so that application won't
re-allocate too much memory.  OTOH, when no preallocation is done,
each substream may allocate arbitrary size of buffers as long as
snd_pcm_hardware.buffer_bytes_max allows -- which can be quite high,
HD-audio sets 1GB there.

It means that the system may consume a high amount of pages for PCM
buffers, and they are pinned and never swapped out.  This can lead to
OOM easily.

For avoiding such a situation, this patch adds the upper limit per
card.  Each snd_pcm_lib_malloc_pages() and _free_pages() calls are
tracked and it will return an error if the total amount of buffers
goes over the defined upper limit.  The default value is set to 32MB,
which should be really large enough for usual operations.

If larger buffers are needed for any specific usage, it can be
adjusted (also dynamically) via snd_pcm.max_alloc_per_card option.
Setting zero there means no chceck is performed, and again, unlimited
amount of buffers are allowed.

Link: https://lore.kernel.org/r/20200120124423.11862-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-21 07:11:55 +01:00
Takashi Iwai
8b57582430 ALSA: core: Treat snd_device_ops as const
This is a preliminary patch to allow const for snd_device_ops
definitions in each driver's code.  The ops reference is read-only,
hence it can be declared as const for further optimization.

There should be no functional changes by this patch.

Link: https://lore.kernel.org/r/20200103081714.9560-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-03 09:23:50 +01:00
Takashi Iwai
fabb26dcd1 ALSA: pcm: Add card sync_irq field
Many PCI and other drivers performs snd_pcm_period_elapsed() simply in
its interrupt handler, so the sync_stop operation is just to call
synchronize_irq().  Instead of putting this call multiple times,
introduce the common card->sync_irq field.  When this field is set,
PCM core performs synchronize_irq() for sync-stop operation.  Each
driver just needs to copy its local IRQ number to card->sync_irq, and
that's all we need.

Link: https://lore.kernel.org/r/20191117085308.23915-8-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-11-20 19:39:54 +01:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Takashi Iwai
f4fa968950 ALSA: core: Don't refer to snd_cards array directly
The snd_cards[] array holds the card pointers that have been currently
registered, and it's exported for the external modules that may need
to refer a card object.  But accessing to this array can be racy
against the driver probe or removal, as the card registration or free
may happen concurrently.

This patch gets rid of the direct access to snd_cards[] array and
provides a helper function to give the card object from the index
number with a refcount management.  Then the caller can access to the
given card object safely, and releases it via snd_card_unref().

While we're at it, add a proper comment to snd_card_unref() and make
it an inlined function for type-safety, too.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-04-17 07:16:15 +02:00
Takashi Iwai
29b2625ff6 ALSA: info: Move card id proc creation into info.c
The creation of card's id proc file can be moved gracefully into
info.c.  Also, the assignment of card->proc_id is superfluous and can
be dropped.  So let's do it.

Basically this is no functional change but code refactoring, but one
potential behavior change is that now it returns properly the error
code from snd_info_card_register(), which is a good thing (tm).

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-02-06 18:11:58 +01:00
Takashi Iwai
dc82e52492 ALSA: core: Assure control device to be registered at last
The commit 289ca025ee ("ALSA: Use priority list for managing device
list") changed the way to register/disconnect/free devices via a
single priority list.  This helped to make behavior consistent, but it
also changed a slight behavior change: namely, the control device is
registered earlier than others, while it was supposed to be the very
last one.

I've put SNDRV_DEV_CONTROL in the current position as the release of
ctl elements often conflict with the private ctl elements some PCM or
other components may create, which often leads to a double-free.
But, the order of register and disconnect should be indeed fixed as
expected in the early days: the control device gets registered at
last, and disconnected at first.

This patch changes the priority list order to move SNDRV_DEV_CONTROL
as the last guy to assure the register / disconnect order.  Meanwhile,
for keeping the messy resource release order, manually treat the
control and lowlevel devices as last freed one.

Additional note:
The lowlevel device is the device where a card driver creates at
probe.  And, we still keep the release order control -> lowlevel, as
there might  be link from a control element back to a lowlevel object.

Fixes: 289ca025ee ("ALSA: Use priority list for managing device list")
Reported-by: Tzung-Bi Shih <tzungbi@google.com>
Tested-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-17 08:21:23 +02:00
Takashi Iwai
c44027c89e ALSA: add snd_card_disconnect_sync()
In case of user unbind ALSA driver during playing back / capturing,
each driver needs to stop and remove it correctly. One note here is
that we can't cancel from remove function in such case, because
unbind operation doesn't check return value from remove function.
So, we *must* stop and remove in this case.

For this purpose, we need to sync (= wait) until the all top-level
operations are canceled at remove function.
For example, snd_card_free() processes the disconnection procedure at
first, then waits for the completion. That's how the hot-unplug works
safely. It's implemented, at least, in the top-level driver removal.

Now for the lower level driver, we need a similar strategy. Notify to
the toplevel for hot-unplug (disconnect in ALSA), and sync with the
stop operation, then continue the rest of its own remove procedure.

This patch adds snd_card_disconnect_sync(), and driver can use it from
remove function.

Note: the "lower level" driver here refers to a middle layer driver
(e.g. ASoC components) that can be unbound freely during operation.
Most of legacy ALSA helper drivers don't have such a problem because
they can't be unbound.

Note#2: snd_card_disconnect_sync() merely calls snd_card_disconnect()
and syncs with closing all pending files.  It takes only the files
opened by user-space into account, and doesn't care about object
refcounts.  (The latter is handled by snd_card_free() completion call,
BTW.)  Also, the function doesn't free resources by itself.

Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-10-11 15:06:10 +02:00
Takashi Iwai
7d8e829201 ALSA: Get rid of card power_lock
Currently we're taking power_lock at each card component for assuring
the power-up sequence, but it doesn't help anything in the
implementation at the moment: it just serializes unnecessarily the
callers, but it doesn't protect about the power state change itself.
It used to have some usefulness in the early days where we managed the
PM manually.  But now the suspend/resume core procedure is beyond our
hands, and power_lock lost its meaning.

This patch drops the power_lock from allover the places.
There shouldn't be any issues by this change, as it's no helper
regarding the power state change.  Rather we'll get better performance
by removing the serialization; which is the only slight concern of any
behavior change, but it can't be a showstopper, after all.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-08-30 20:44:29 +02:00
Takashi Sakamoto
30d8340b58 ALSA: control: obsolete user_ctl_lock
At a previous commit, concurrent requests for TLV data are maintained
exclusively between read requests and write/command requests. TLV
callback handlers in each driver has no risk from concurrent access for
reference/change.

In current implementation, 'struct snd_card' has a mutex to control
concurrent accesses to user-defined element sets. This commit obsoletes it.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-08-04 16:50:55 +02:00
Takashi Iwai
6d2412b80a ALSA: Use IS_ENABLED() in common headers
Simplify the ifdef conditions with IS_ENABLED() macro in the common
sound headers.  No functional changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-05-17 07:13:04 +02:00
Takashi Iwai
43e575fabb ALSA: core: Fix kernel-doc warnings
Several lines in sound/core.h get the kernel-doc warnings like

  ./include/sound/core.h:323: warning: No description found for parameter '...'

where we use define like foo(x, args...) and "args" isn't mentioned in
the comments.  As an easy workaround, use simple __VA_ARGS__ for VLA
in macros.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-11-15 07:28:18 +01:00
Heiner Kallweit
de65360be0 ALSA: hda_intel: add card number to irq description
Currently the info in /proc/interrupts doesn't allow to figure out which
interrupt belongs to which card (HDMI, PCH, ..).
Therefore add card details to the interrupt description.
With the patch the info in /proc/interrupts looks like this:

PCI-MSI 442368-edge      snd_hda_intel:card1
PCI-MSI 49152-edge      snd_hda_intel:card0

NOTE: this patch adds the new irq_descr field snd_card struct that is
filled automatically at a card object creation.  This can be used
generically for other drivers as well.  The changes for others will
follow later -- tiwai

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-01-12 21:05:16 +01:00
Takashi Iwai
b046d244e2 ALSA: core: Remove superfluous exit calls for proc entries
Since each proc entry is freed automatically by the parent, we don't
have to take care of its life cycle any longer.  This allows us to
reduce a few more lines of codes.

Acked-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-04-24 17:31:04 +02:00
Takashi Iwai
e086e3035e ALSA: core: Re-add snd_device_disconnect()
Revive snd_device_disconnect() again so that it can be called from the
individual driver.  This time, HD-audio will need it.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-03-03 11:26:28 +01:00
Takashi Iwai
6bbc7fed84 ALSA: Add a helper to add a new attribute group to card
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: Takashi Iwai <tiwai@suse.de>
2015-02-06 09:56:33 +01:00
Takashi Iwai
830953c072 ALSA: Drop snd_get_device() helper
Since the device is no longer hidden but embedded into each component,
we no longer need snd_get_device().  Let's drop it and relevant codes.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-02 17:01:38 +01:00
Takashi Iwai
40a4b26385 ALSA: Simplify snd_device_register() variants
Now that all callers have been replaced with
snd_device_register_for_dev(), let's drop the obsolete device
registration code and concentrate only on the code handling struct
device directly.  That said,

- remove the old snd_device_register(),
- rename snd_device_register_for_dev() with snd_device_register(),
- drop superfluous arguments from snd_device_register(),
- change snd_unregister_device() to pass the device pointer directly

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-02 17:01:26 +01:00
Takashi Iwai
0fcd9f4b3c ALSA: control: Embed struct device
This patch embeds a struct device for the control device into the card
object and avoid the device creation at registration time.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-02 14:42:41 +01:00
Takashi Iwai
4b440be667 ALSA: Add a helper to initialize device
Introduce a new helper function snd_device_initialize() to initialize
the device object for sound devices.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-02 14:42:33 +01:00
Takashi Iwai
92b7952da8 ALSA: Allow to pass the device object to snd_register_device*()
This is a preliminary patch for the further work on embedding struct
device into each sound device instance.  It changes
snd_register_device*() helpers to receive the device object directly
for skipping creating a device there.

Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-02 14:21:07 +01:00
Lars-Peter Clausen
07f4d9d74a ALSA: control: Protect user controls against concurrent access
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: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jaroslav Kysela <perex@perex.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-06-18 15:12:33 +02:00
Takashi Iwai
038b8455db ALSA: Remove deprecated snd_card_create()
Now all calls have been fixed, let's get rid of the old definition.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-05-23 09:57:55 +02:00
Dylan Reid
f0a220dedd ALSA: core - Define snd_pci_quirk without CONFIG_PCI
The hda codecs all use this struct and, with an HDA platform driver,
will be able to be built without PCI.

Signed-off-by: Dylan Reid <dgreid@chromium.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-03-01 11:23:41 +01:00
Takashi Iwai
72620d6048 ALSA: Clean up snd_device_*() codes
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: Takashi Iwai <tiwai@suse.de>
2014-02-25 12:12:52 +01:00
Takashi Iwai
289ca025ee ALSA: Use priority list for managing device list
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: Takashi Iwai <tiwai@suse.de>
2014-02-25 12:12:51 +01:00
Takashi Iwai
caa751bad4 ALSA: Create sysfs attribute files via groups
Instead of calling each time device_create_file(), create the groups
of sysfs attribute files at once in a normal way.  Add a new helper
function, snd_get_device(), to return the associated device object,
so that we can handle the sysfs addition locally.

Since the sysfs file addition is done differently now,
snd_add_device_sysfs_file() helper function is removed.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-02-25 12:12:49 +01:00
Takashi Iwai
9ce5054363 ALSA: Drop __bitwise and typedefs for snd_device attributes
Using __bitwise and typedefs for the attributes of snd_device struct
isn't so useful, and rather it worsens the readability.  Let's drop
them and use the straightforward enum.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-02-14 08:20:24 +01:00
Takashi Iwai
f246406481 ALSA: Use standard device refcount for card accounting
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: Takashi Iwai <tiwai@suse.de>
2014-02-14 08:14:13 +01:00
Takashi Iwai
8bfb181c17 ALSA: Embed card device into struct snd_card
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: Takashi Iwai <tiwai@suse.de>
2014-02-14 08:14:12 +01:00
Takashi Iwai
393aa9c1cc ALSA: Mandate to pass a device pointer at card creation time
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: Takashi Iwai <tiwai@suse.de>
2014-02-12 10:58:20 +01:00
Takashi Iwai
80d7d771ae ALSA: Drop unused name argument in snd_register_oss_device()
The last argument, name, of snd_oss_register_device() is nowhere
referred in the function in the current code.  Let's drop it.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-02-12 10:58:19 +01:00
Tim Gardner
bcbb15530e ALSA: pcm: Add snd_printd_ratelimit()
Direct calls to printk_limit() will emit log noise even when CONFIG_SND_DEBUG is not
defined. Add a wrapper macro around printk_limit() that is conditionally defined by
CONFIG_SND_DEBUG.

Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Yacine Belkadi <yacine.belkadi.1@gmail.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-08-19 15:48:33 +02:00
Takashi Iwai
7bb2491b35 ALSA: Add kconfig to specify the max card numbers
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: Takashi Iwai <tiwai@suse.de>
2013-05-24 16:41:46 +02:00
Yacine Belkadi
eb7c06e8e9 ALSA: add/change some comments describing function return values
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: Yacine Belkadi <yacine.belkadi.1@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-03-12 08:32:53 +01:00
Christine Spang
d5702162f8 ALSA: Make snd_BUG_ON() always evaluate and return the conditional expression
Having snd_BUG_ON() only evaluate its conditional when CONFIG_SND_DEBUG
is set leads to frequent bugs, since other similar macros in the kernel
have different behavior. Let's make snd_BUG_ON() act like those macros
so it will stop being accidentally misused.

Signed-off-by: Christine Spang <christine.spang@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-03-11 09:33:34 +01:00
Takashi Iwai
86b2723725 ALSA: Make snd_printd() and snd_printdd() inline
Because currently snd_printd() and snd_printdd() macros are expanded
to empty when CONFIG_SND_DEBUG=n, a compile warning like below
appears sometimes, and we had to covert it by ugly ifdefs:
  sound/pci/hda/patch_sigmatel.c: In function ‘stac92hd71bxx_fixup_hp’:
  sound/pci/hda/patch_sigmatel.c:2434:24: warning: unused variable ‘spec’ [-Wunused-variable]

For "fixing" these issues better, this patch replaces snd_printd() and
snd_printdd() definitions with empty inline functions instead of
macros.  This should have the same effect but shut up warnings like
above.

But since we had already put ifdefs, changing to inline functions
would trigger compile errors.  So, such ifdefs is removed in this
patch.

In addition, snd_pci_quirk name field is defined only when
CONFIG_SND_DEBUG_VERBOSE is set, and the reference to it in
snd_printdd() argument triggers the build errors, too.  For avoiding
these errors, introduce a new macro snd_pci_quirk_name() that is
defined no matter how the debug option is set.

Reported-by: Stratos Karafotis <stratosk@semaphore.gr>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-01-25 18:32:14 +01:00
Takashi Iwai
a0830dbd4e ALSA: Add a reference counter to card instance
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: Matthieu CASTET <matthieu.castet@parrot.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2012-10-30 11:07:10 +01:00