[Debian-eeepc-devel] Bug#574844: SNDRV_PCM_IOCTL_RESUME failed: Function not implemented

[trentbuck at gmail.com]

# New evidence suggests this problem is mplayer-specific.
reassign 575844 mplayer
found 575844 1.0~rc3+svn20090405-1+b1
thanks

Consider the following transcript.  First, we generate a test file:

    $ mplayer -really-quiet -ao pcm:fast -vo null -vc null http://he3.magnatune.com/all/01-Aurore-Gerard%20Satamian-lofi.mp3

Plain aplay works:

    $ sleep 10 && sudo tee <<<mem /sys/power/state & aplay audiodump.wav
    [1] 5764
    Playing WAVE 'audiodump.wav' : Signed 16 bit Little Endian, Rate 22050 Hz, Stereo
    mem
    Suspended. Trying resume. Done.
    underrun!!! (at least -1270530282992.973 ms long)
      C-c C-cAborted by signal Interrupt...
    [1]+  Done                    sleep 10 && sudo tee /sys/power/state <<< mem

Hmm, this works, too, though the delay between resuming the system and
the audio continuing to play is much longer than with aplay.

    $ sleep 10 && sudo tee <<<mem /sys/power/state & mplayer -noconsolecontrols -quiet audiodump.wav
    [1] 2832
    MPlayer SVN-r29142-4.4.3 (C) 2000-2009 MPlayer Team

    Playing audiodump.wav.
    Audio only file format detected.
    ==========================================================================
    Opening audio decoder: [pcm] Uncompressed PCM audio decoder
    AUDIO: 22050 Hz, 2 ch, s16le, 705.6 kbit/100.00% (ratio: 88200->88200)
    Selected audio codec: [pcm] afm: pcm (Uncompressed PCM)
    ==========================================================================
    AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample)
    Video: no video
    Starting playback...
    mem
    [AO_ALSA] Pcm in suspend mode, trying to resume.
    [AO_ALSA] alsa-lib: pcm_hw.c:709:(snd_pcm_hw_resume) SNDRV_PCM_IOCTL_RESUME failed: Function not implemented
      C-c C-c

    MPlayer interrupted by signal 2 in module: play_audio

    Exiting... (Quit)
    [1]+  Done                    sleep 10 && sudo tee /sys/power/state <<< mem

But this doesn't:

    $ sleep 10 && sudo tee <<<mem /sys/power/state & mplayer audiodump.wav
    [1] 5698
    MPlayer SVN-r29142-4.4.3 (C) 2000-2009 MPlayer Team

    Playing audiodump.wav.
    Audio only file format detected.
    ==========================================================================
    Opening audio decoder: [pcm] Uncompressed PCM audio decoder
    AUDIO: 22050 Hz, 2 ch, s16le, 705.6 kbit/100.00% (ratio: 88200->88200)
    Selected audio codec: [pcm] afm: pcm (Uncompressed PCM)
    ==========================================================================
    AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample)
    Video: no video
    Starting playback...
    mem
    [AO_ALSA] Pcm in suspend mode, trying to resume.
    [AO_ALSA] alsa-lib: pcm_hw.c:709:(snd_pcm_hw_resume) SNDRV_PCM_IOCTL_RESUME failed: Function not implemented
      C-c C-c

    MPlayer interrupted by signal 2 in module: play_audio
      C-c C-c

    MPlayer interrupted by signal 2 in module: play_audio
    [1]+  Done                    sleep 10 && sudo tee /sys/power/state <<< mem

This makes me suspect some part of mplayer's terminal interaction
code.

These tests were done within Emacs' M-x shell, where TERM=dumb and
stdio is connected to a tty (i.e. "test -t 0 -a -t 1 -a -t 2" passes).

The behaviour above is consistent for kernels
linux-image-2.6.32-3-amd64 (2.6.32-9) and linux-image-2.6.33-2-amd64
(2.6.33-1~experimental.4).  For each, alsa-info.sh yields
http://www.alsa-project.org/db/?f=3d1754592d25ecf773a04984473c7eefeda581de
http://www.alsa-project.org/db/?f=df81bc3978db0e9a08685581da7614548dd41acc