[alsa-devel] snd_pcm_rewind() weirdness

[Lennart Poettering]

On Mon, 21.04.08 08:58, Jaroslav Kysela (perex at perex.cz) wrote:

> 
> On Sun, 20 Apr 2008, Lennart Poettering wrote:
> 
> > Hey!
> > 
> > On ALSA 1.0.16 with the HDA driver I am experiencing some weird things
> > with snd_pcm_rewind() which I think are the result of a kernel bug,
> > but I am not sure.
> 
> What alsa-lib plugins are on path? It looks like a rate plugin issue. Post 
> also snd_pcm_dump() output. Driver does not do any alignment.

It's front:0. I don't think the rate plugin is used. 

Device is being opened with
SND_PCM_NO_AUTO_RESAMPLE|SND_PCM_NO_AUTO_CHANNELS|SND_PCM_NO_AUTO_FORMAT
and snd_pcm_hw_params_set_rate_resample(..., 0).

That should get me only softvol, right?

The output of snd_pcm_dump() is here (please ignore the "D:
alsa-util.c" prefix)

<snip>
D: alsa-util.c: Soft volume PCM
D: alsa-util.c: Control: PCM Playback Volume
D: alsa-util.c: min_dB: -51
D: alsa-util.c: max_dB: 0
D: alsa-util.c: resolution: 256
D: alsa-util.c: Its setup is:
D: alsa-util.c:   stream       : PLAYBACK
D: alsa-util.c:   access       : MMAP_INTERLEAVED
D: alsa-util.c:   format       : S16_LE
D: alsa-util.c:   subformat    : STD
D: alsa-util.c:   channels     : 2
D: alsa-util.c:   rate         : 44100
D: alsa-util.c:   exact rate   : 44100 (44100/1)
D: alsa-util.c:   msbits       : 16
D: alsa-util.c:   buffer_size  : 16384
D: alsa-util.c:   period_size  : 8192
D: alsa-util.c:   period_time  : 185759
D: alsa-util.c:   tstamp_mode  : NONE
D: alsa-util.c:   period_step  : 1
D: alsa-util.c:   avail_min    : 31001
D: alsa-util.c:   start_threshold  : -1
D: alsa-util.c:   stop_threshold   : -1
D: alsa-util.c:   silence_threshold: 0
D: alsa-util.c:   silence_size : 0
D: alsa-util.c:   boundary     : 4611686018427387904
D: alsa-util.c: Slave: Hardware PCM card 4 'HDA Intel' device 0 subdevice 0
D: alsa-util.c: Its setup is:
D: alsa-util.c:   stream       : PLAYBACK
D: alsa-util.c:   access       : MMAP_INTERLEAVED
D: alsa-util.c:   format       : S16_LE
D: alsa-util.c:   subformat    : STD
D: alsa-util.c:   channels     : 2
D: alsa-util.c:   rate         : 44100
D: alsa-util.c:   exact rate   : 44100 (44100/1)
D: alsa-util.c:   msbits       : 16
D: alsa-util.c:   buffer_size  : 16384
D: alsa-util.c:   period_size  : 8192
D: alsa-util.c:   period_time  : 185759
D: alsa-util.c:   tstamp_mode  : NONE
D: alsa-util.c:   period_step  : 1
D: alsa-util.c:   avail_min    : 31001
D: alsa-util.c:   start_threshold  : -1
D: alsa-util.c:   stop_threshold   : -1
D: alsa-util.c:   silence_threshold: 0
D: alsa-util.c:   silence_size : 0
D: alsa-util.c:   boundary     : 4611686018427387904
</snip>

Lennart

-- 
Lennart Poettering                        Red Hat, Inc.
lennart [at] poettering [dot] net         ICQ# 11060553
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