[ALSA - driver 0000758]: Full duplex is not working in OSS emulation.

bugtrack
2006-05-10T12:56:38Z

Last Modified: 05-10-2006 14:56 CEST
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Summary: Full duplex is not working in OSS emulation.
Description:
If I play something with one player, I am unable to record something on the
same device.
The same thing ispossible with the other cards I have.
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Relationships ID Summary
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related to 0000521 Jack + Alsa not working in full duplex,...
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croiset - 05-09-06 15:49
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We put some logs in rme96.c for debugging the problem.

We obtain this :

The function snd_rme96_capture_hw_params returns -EBUSY when we open the
analog capture device when the analog output device is already opened in
play mode because :

rme96->playback_periodsize = 2048
rme96->capture_frlog = 2
params_period_size(params)=2048

then the tsst in line 1052 (alsa 1.0.11) is valid and then returns -EBUSY

If the analog output device is not opened, when we capture, the values are
:
rme96->playback_periodsize = 0
rme96->capture_frlog = 2
params_period_size(params)=2048

then the test is not valid and the device is working.

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tiwai - 05-10-06 14:56
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That makes sense. RME96 requests exactly the same condition for playback
and capture sides.
When you use OSS, each ioctl tries to change one parameter, and at some
stage, it results in an incompatible state. Usually this should be
restricted via hw_constraint settings, but rme96.c has no proper code for
that.

Issue History
Date Modified Username Field Change
======================================================================
12-29-04 10:15 croiset New Issue
12-29-04 10:15 croiset Distribution => Redhat 7.2
12-29-04 10:15 croiset Kernel Version => 2.4.7
12-29-04 14:17 tiwai Note Added: 0002998
12-29-04 14:54 croiset Note Added: 0003000
12-29-04 17:39 tiwai Note Added: 0003004
12-29-04 17:56 croiset Note Added: 0003005
12-29-04 17:59 croiset Note Added: 0003006
12-29-04 18:05 croiset Note Edited: 0003006
12-29-04 18:18 croiset Note Edited: 0003006
01-03-05 16:30 croiset Note Added: 0003067
09-14-05 16:16 jdthood Relationship added related to 0000521
12-30-05 23:08 rlrevell Note Added: 0007278
01-02-06 09:12 croiset Note Added: 0007368
05-09-06 14:09 croiset Note Added: 0009657
05-09-06 15:49 croiset Note Added: 0009659
05-10-06 14:56 tiwai Note Added: 0009717
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