[alsa-devel] need help with loopback driver

[Olivier Langlois]

Ok mystery solved. the refinement failing wasn't in pcm_rate with params
from pcm_multi but in pcm_hw with pcm_rate params.

The problem was on my side since I forgot to change the sampling rate
from 44100 to 48000 on the aloop capture side. Again depending on the
order I was initializing the aloop subdevices, this was creating a param
mismatch or not.

On Thu, 2013-12-26 at 15:07 -0500, Olivier Langlois wrote:
> Concerning the last problem. Here it is 'loop_44100_16' refine sometimes
> works and sometimes it doesn't. Either something invisible to the param
> dumps is different or maybe some uninitialized variables adds some
> randomness to the result:
> 
> srefine 'loop_44100_16' (client)
> ACCESS:  MMAP_INTERLEAVED MMAP_NONINTERLEAVED
> FORMAT:  S16_LE S32_LE
> SUBFORMAT:  STD
> SAMPLE_BITS: ALL
> FRAME_BITS: ALL
> CHANNELS: 2
> RATE: 192000
> PERIOD_TIME: (20 682667)
> PERIOD_SIZE: [4 131072]
> PERIOD_BYTES: ALL
> PERIODS: [2 32]
> BUFFER_TIME: (41 1365334)
> BUFFER_SIZE: [8 262144]
> BUFFER_BYTES: ALL
> TICK_TIME: ALL
> srefine 'loop_44100_16' (slave)
> ACCESS:  MMAP_INTERLEAVED MMAP_NONINTERLEAVED MMAP_COMPLEX
> FORMAT:  S16_LE
> SUBFORMAT:  STD
> SAMPLE_BITS: ALL
> FRAME_BITS: ALL
> CHANNELS: 2
> RATE: [48000 48001)
> PERIOD_TIME: (20 682667)
> PERIOD_SIZE: ALL
> PERIOD_BYTES: ALL
> PERIODS: ALL
> BUFFER_TIME: ALL
> BUFFER_SIZE: [2 65538)
> BUFFER_BYTES: ALL
> TICK_TIME: ALL
> REFINE called:
> ACCESS:  MMAP_INTERLEAVED MMAP_NONINTERLEAVED MMAP_COMPLEX
> FORMAT:  S16_LE
> SUBFORMAT:  STD
> SAMPLE_BITS: ALL
> FRAME_BITS: ALL
> CHANNELS: 2
> RATE: [48000 48001)
> PERIOD_TIME: (20 682667)
> PERIOD_SIZE: ALL
> PERIOD_BYTES: ALL
> PERIODS: ALL
> BUFFER_TIME: ALL
> BUFFER_SIZE: [2 65538)
> BUFFER_BYTES: ALL
> TICK_TIME: ALL
> refine done - result = 0
> 
> 
> lano1106 at Wailaba2 ~/dev/alsa_debug $ diff refine_success.txt
> refine_fail.txt 
> 49c49,50
> < refine done - result = 0
> ---
> > refine done - result = -22