linux.git/sound/usb/proc.c, branch v5.8

ALSA: usb-audio: Fix a limit check in proc_dump_substream_formats()

2020-04-22T09:29:15+00:00

This should be ARRAY_SIZE() instead of sizeof().  The sizeof() limit is
too high so it doesn't work.

Fixes: 093b8494f299 ("ALSA: usb-audio: Print more information in stream proc files")
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20200422092255.GB195357@mwanda
Signed-off-by: Takashi Iwai

ALSA: usb-audio: Print more information in stream proc files

2020-04-19T22:22:04+00:00

For more debug and usability information, add the entry showing the
DSD raw states and the channel mapping in each stream proc file.

Link: https://lore.kernel.org/r/20200419212134.14200-1-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: usb-audio: Use pcm_for_each_format() macro for PCM format iterations

2020-02-10T07:27:19+00:00

The new macro can fix the sparse warnings gracefully:
  sound/usb/proc.c:73:31: warning: restricted snd_pcm_format_t degrades to integer
  sound/usb/proc.c:73:38: warning: restricted snd_pcm_format_t degrades to integer
  sound/usb/proc.c:73:61: warning: restricted snd_pcm_format_t degrades to integer

No functional changes, just sparse warning fixes.

Link: https://lore.kernel.org/r/20200206163945.6797-4-tiwai@suse.de
Signed-off-by: Takashi Iwai

ALSA: usb-audio: More constifications

2020-01-05T15:14:34+00:00

Apply const prefix to the remaining places: the static table for the
unit information, the mixer maps, the validator tables, etc.

Just for minor optimization and no functional changes.

Link: https://lore.kernel.org/r/20200105144823.29547-12-tiwai@suse.de
Signed-off-by: Takashi Iwai

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

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 
Reviewed-by: Allison Randal 
Reviewed-by: Richard Fontana 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman

ALSA: usb-audio: Expose sample resolution through proc interface

2019-02-18T08:36:09+00:00

At least some USB devices use (MSB-aligned) audio format larger
than the actual resolution of the device. In order to expose the
actual device resolution (bBitResolution), add extra field to the
procfs stream info interface.

Signed-off-by: Jussi Laako 
Signed-off-by: Takashi Iwai

ALSA: usb: Clean up with new procfs helpers

2019-02-06T17:11:57+00:00

Simplify the proc fs creation code with new helper functions,
snd_card_ro_proc_new() and snd_card_rw_proc_new().
Just a code refactoring and no functional changes.

Reviewed-by: Jaroslav Kysela 
Signed-off-by: Takashi Iwai

ALSA: usb-audio: Avoid nested autoresume calls

2015-08-26T13:38:25+00:00

After the recent fix of runtime PM for USB-audio driver, we got a
lockdep warning like:

  =============================================
  [ INFO: possible recursive locking detected ]
  4.2.0-rc8+ #61 Not tainted
  ---------------------------------------------
  pulseaudio/980 is trying to acquire lock:
   (&chip->shutdown_rwsem){.+.+.+}, at: [] snd_usb_autoresume+0x1d/0x52 [snd_usb_audio]
  but task is already holding lock:
   (&chip->shutdown_rwsem){.+.+.+}, at: [] snd_usb_autoresume+0x1d/0x52 [snd_usb_audio]

This comes from snd_usb_autoresume() invoking down_read() and it's
used in a nested way.  Although it's basically safe, per se (as these
are read locks), it's better to reduce such spurious warnings.

The read lock is needed to guarantee the execution of "shutdown"
(cleanup at disconnection) task after all concurrent tasks are
finished.  This can be implemented in another better way.

Also, the current check of chip->in_pm isn't good enough for
protecting the racy execution of multiple auto-resumes.

This patch rewrites the logic of snd_usb_autoresume() & co; namely,
- The recursive call of autopm is avoided by the new refcount,
  chip->active.  The chip->in_pm flag is removed accordingly.
- Instead of rwsem, another refcount, chip->usage_count, is introduced
  for tracking the period to delay the shutdown procedure.  At
  the last clear of this refcount, wake_up() to the shutdown waiter is
  called.
- The shutdown flag is replaced with shutdown atomic count; this is
  for reducing the lock.
- Two new helpers are introduced to simplify the management of these
  refcounts; snd_usb_lock_shutdown() increases the usage_count, checks
  the shutdown state, and does autoresume.  snd_usb_unlock_shutdown()
  does the opposite.  Most of mixer and other codes just need this,
  and simply returns an error if it receives an error from lock.

Fixes: 9003ebb13f61 ('ALSA: usb-audio: Fix runtime PM unbalance')
Reported-and-tested-by: Alexnader Kuleshov 
Signed-off-by: Takashi Iwai

ALSA: usb-audio: proc: use found syncmaxsize to determine feedback format

2013-05-17T06:05:34+00:00

freqshift is only set for the data endpoint and syncmaxsize is only set
for the sync endpoint. This results in a syncmaxsize of zero used in the
proc output feedback format calculation, which gives a feedback format
incorrectly shown as 8.16 for UAC2 devices.

As neither the data nor the sync endpoint gives all the relevant
content, output the two combined.

Also remove the sync_endpoint "packet size" which is always zero
and the sync_endpoint "momentary freq" which is constant.

Tested with UAC2 async and UAC1 adaptive, not tested with UAC1 async.

Reported-by: B. Zhang 
Signed-off-by: Torstein Hegge 
Signed-off-by: Takashi Iwai

ALSA: pcm_format_to_bits strong-typed conversion

2013-04-29T11:36:15+00:00

Add a function to handle conversion from snd_pcm_format_t
to bitwise with proper typing.

Change such conversions to use this function and silence sparse
warnings.

Signed-off-by: Eldad Zack 
Signed-off-by: Takashi Iwai