linux-toradex.git/sound/core/pcm_lib.c, branch v4.10

ALSA: pcm: Bail out when chmap is already present

2016-05-10T15:05:16+00:00

When snd_pcm_add_chmap_ctls() is called to the PCM stream to which a
chmap has been already assigned, it returns as an error due to the
conflicting snd_ctl_add() result.  However, this also clears the
already assigned chmap_kctl field via pcm_chmap_ctl_private_free(),
and becomes inconsistent in the later operation.

This patch adds the check of the conflicting chmap kctl before
actually trying to allocate / assign.  The check failure is treated as
a kernel warning, as the double call of snd_pcm_add_chmap_ctls() is
basically a driver bug and having the stack trace would help
developers to figure out the bad code path.

Signed-off-by: Takashi Iwai

ALSA: pcm : Call kill_fasync() in stream lock

2016-04-14T16:02:37+00:00

Currently kill_fasync() is called outside the stream lock in
snd_pcm_period_elapsed().  This is potentially racy, since the stream
may get released even during the irq handler is running.  Although
snd_pcm_release_substream() calls snd_pcm_drop(), this doesn't
guarantee that the irq handler finishes, thus the kill_fasync() call
outside the stream spin lock may be invoked after the substream is
detached, as recently reported by KASAN.

As a quick workaround, move kill_fasync() call inside the stream
lock.  The fasync is rarely used interface, so this shouldn't have a
big impact from the performance POV.

Ideally, we should implement some sync mechanism for the proper finish
of stream and irq handler.  But this oneliner should suffice for most
cases, so far.

Reported-by: Baozeng Ding 
Signed-off-by: Takashi Iwai

ALSA: pcm: Avoid "BUG:" string for warnings again

2016-03-10T20:00:17+00:00

The commit [d507941beb1e: ALSA: pcm: Correct PCM BUG error message]
made the warning prefix back to "BUG:" due to its previous wrong
prefix.  But a kernel message containing "BUG:" seems taken as an Oops
message wrongly by some brain-dead daemons, and it annoys users in the
end.  Instead of teaching daemons, change the string again to a more
reasonable one.

Fixes: 507941beb1e ('ALSA: pcm: Correct PCM BUG error message')
Cc:  # v3.19+
Signed-off-by: Takashi Iwai

ALSA: Constify ratden/ratnum constraints

2015-10-28T10:42:22+00:00

The ALSA core does not modify the constraints provided by a driver. Most
constraint helper functions already take a const pointer to the constraint
description, the exception at the moment being the ratden and ratnum
constraints. Make those const as well, this allows a driver to declare them
as const.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Takashi Iwai

ALSA: Remove transfer_ack_{begin,end} callbacks from struct snd_pcm_runtime

2015-10-22T15:16:23+00:00

While there is nothing wrong with the transfer_ack_begin and
transfer_ack_end callbacks per-se, the last documented user was part of the
alsa-driver 0.5.12a package, which was released 14 years ago and even
predates the upstream integration of the ALSA core and has subsequently
been superseded by newer alsa-driver releases.

This seems to indicate that there is no need for having these callbacks and
they are just cruft that can be removed.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Takashi Iwai

ALSA: timer: add config item to export PCM timer disabling for expert

2015-10-16T12:31:38+00:00

PCM timer is not always used. For embedded device, we need an interface
to disable it when it is not needed, to shrink the kernel size and
memory footprint, here add CONFIG_SND_PCM_TIMER for it.

When both CONFIG_SND_PCM_TIMER and CONFIG_SND_TIMER is unselected,
about 25KB saving bonus we can get.

Please be noted that when disabled, those stubs who using pcm timer
(e.g. dmix, dsnoop & co) may work incorrectlly.

Suggested-by: Takashi Iwai 
Signed-off-by: Jie Yang 
Signed-off-by: Takashi Iwai

ALSA: pcm: Modify double acknowledged interrupts check condition

2015-05-19T07:32:29+00:00

Currently in snd_pcm_update_hw_ptr0 during interrupt,
we consider there were double acknowledged interrupts when:
1. HW reported pointer is smaller than expected, and
2. Time from last update time (hdelta) is over half a buffer time.

However, when HW reported pointer is only a few bytes smaller than
expected, and when hdelta is just a little larger than half a buffer time
(e.g. ping-pong buffer), it wrongly treats this IRQ as double acknowledged.

The condition #2 uses jiffies, but jiffies is not high resolution
since it is integer. We should consider jiffies inaccuracy.

Signed-off-by: Koro Chen 
Signed-off-by: Takashi Iwai

ALSA: core: add .get_time_info

2015-02-20T16:30:05+00:00

Introduce more generic .get_time_info to retrieve
system timestamp and audio timestamp in single routine.
Backwards compatibility is preserved with same functionality
as with .wall_clock method (to be removed in following commits
to avoid breaking git bisect)

Signed-off-by: Pierre-Louis Bossart 
Signed-off-by: Takashi Iwai

Merge tag 'asoc-v3.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-next

2015-02-05T06:08:35+00:00

ASoC: Updates for v3.20

More updates for v3.20:

 - Lots of refactoring from Lars-Peter Clausen, moving drivers to more
   data driven initialization and rationalizing a lot of DAPM usage.
 - Much improved handling of CDCLK clocks on Samsung I2S controllers.
 - Lots of driver specific cleanups and feature improvements.
 - CODEC support for TI PCM514x and TLV320AIC3104 devices.
 - Board support for Tegra systems with Realtek RT5677.

Conflicts:
	sound/soc/intel/sst-mfld-platform-pcm.c

ALSA: pcm: Add snd_interval_ranges() and snd_pcm_hw_constraint_ranges()

2015-01-28T19:27:15+00:00

Add helper functions to allow drivers to specify several disjoint
ranges for a variable. In particular, there is a codec (PCM512x) that
has a hole in its supported range of rates, due to PLL and divider
restrictions.

This is like snd_pcm_hw_constraint_list(), but for ranges instead of
points.

Signed-off-by: Peter Rosin 
Reviewed-by: Lars-Peter Clausen 
Reviewed-by: Takashi Iwai 
Signed-off-by: Mark Brown