Messages in this thread | | | Date | Wed, 27 Apr 2016 17:15:04 +0100 | From | Mark Brown <> | Subject | Re: [PATCH] ASoC: pcm: allow changing the playback/capture rates for symmetric links |
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On Wed, Apr 27, 2016 at 10:49:19AM +0200, Peter Rosin wrote:
> The below program fails on a dai link with symmetric rates without this > patch. The patch makes it work.
You've not articulated the problem you're trying to fix here, what in concrete terms is the program trying to accomplish and why should it succeed?
> if ((fd = open("/dev/dsp", O_WRONLY, 0)) == -1) { > perror("open"); > return 1; > }
This is using the OSS interfaces which really haven't ever been especially supported for ASoC.
> + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { > + if (!cpu_dai->capture_active) > + return 0; > + } else if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) { > + if (!cpu_dai->playback_active) > + return 0; > + } > + > rate = params_rate(params); > channels = params_channels(params); > sample_bits = snd_pcm_format_physical_width(params_format(params));
This means we've opened up a race where the stream is configured but not started where the opposite direction can configure a different setup. Since starting both directions very close together is a common operation it seems likely to cause issues. [unhandled content-type:application/pgp-signature] | |