The USB disconnect callback is supposed to be short and not too-long
waiting.  OTOH, the current code uses snd_card_free() at
disconnection, but this waits for the close of all used fds, hence it
can take long.  It eventually blocks the upper layer USB ioctls, which
may trigger a soft lockup.

An easy workaround is to replace snd_card_free() with
snd_card_free_when_closed().  This variant returns immediately while
the release of resources is done asynchronously by the card device
release at the last close.

This patch also splits the code to the disconnect and the free phases;
the former is called immediately at the USB disconnect callback while
the latter is called from the card destructor.

Fixes: 523f1dce3743 ("[ALSA] Add Native Instrument usb audio device support")
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20241113111042.15058-5-tiwai@suse.de

The recent cleanup of caiaq driver forgot to remove the unused loop
variable:
sound/usb/caiaq/audio.c: In function 'snd_usb_caiaq_pcm_prepare':
sound/usb/caiaq/audio.c:179:41: error: unused variable 'i' [-Werror=unused-variable]

Fixes: e95b9f7f2ee0 ("ALSA: snd-usb-caiaq: use snd_pcm_rate_to_rate_bit")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/20240809112252.5af8025f@canb.auug.org.au
Link: https://patch.msgid.link/20240809074254.5290-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Use snd_pcm_rate_to_rate_bit() helper provided by Alsa instead
re-implementing it. This reduce code duplication and helps when
changing some Alsa definition is necessary.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://patch.msgid.link/20240808134857.86749-1-jbrunet@baylibre.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Replace the old __attribute__((packed)) with the new __packed.
Only cleanup, no functional changes.

Link: https://lore.kernel.org/r/20231025132314.5878-7-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

The filling of card->longname can be gracefully truncated, as it's
only informative.  Use scnprintf() and suppress the superfluous
compile warning with -Wformat-truncation.

Link: https://lore.kernel.org/r/20230915082802.28684-5-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Smatch complains that:
snd_usb_caiaq_input_init() warn: missing error code 'ret'

This patch adds a new case to handle the situation where the
device does not support any input methods in the
`snd_usb_caiaq_input_init` function. It returns an `-EINVAL` error code
to indicate that no input methods are supported on the device.

Fixes: 523f1dce3743 ("[ALSA] Add Native Instrument usb audio device support")
Signed-off-by: Ruliang Lin <u202112092@hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Acked-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20230504065054.3309-1-u202112092@hust.edu.cn
Signed-off-by: Takashi Iwai <tiwai@suse.de>

MODULE_SUPPORTED_DEVICE was added in pre-git era and never was
implemented. We can safely remove it, because the kernel has grown
to have many more reliable mechanisms to determine if device is
supported or not.

Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

strlcpy is deprecated.  see: Documentation/process/deprecated.rst

Change the calls that do not use the strlcpy return value to the
preferred strscpy.

Done with cocci script:

@@
expression e1, e2, e3;
@@

-	strlcpy(
+	strscpy(
	e1, e2, e3);

This cocci script leaves the instances where the return value is
used unchanged.

After this patch, sound/ has 3 uses of strlcpy() that need to be
manually inspected for conversion and changed one day.

$ git grep -w strlcpy sound/
sound/usb/card.c:               len = strlcpy(card->longname, s, sizeof(card->longname));
sound/usb/mixer.c:      return strlcpy(buf, p->name, buflen);
sound/usb/mixer.c:                      return strlcpy(buf, p->names[index], buflen);

Miscellenea:

o Remove trailing whitespace in conversion of sound/core/hwdep.c

Link: https://lore.kernel.org/lkml/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/22b393d1790bb268769d0bab7bacf0866dcb0c14.camel@perches.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

A few places (except for ASoC) are left unconverted for the new
fallthrough pseudo keyword.  Now replace them all.

Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200709111750.8337-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Apply const prefix to each possible place: the rate table, the
controller tables, and the key tables.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-13-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>