On Fri, Mar 19, 2010 at 08:56:40AM +0200, Peter Ujfalusi wrote: > On Thursday 18 March 2010 21:23:58 ext Daniel Mack wrote: > > This fixes a memory corruption when ASoC devices are used in > > full-duplex mode. Specifically for pxa-ssp code, where this pointer > > is dynamically allocated for each direction and destroyed upon each > > stream start. > > > > All other platforms are fixed blindly, I couldn't even compile-test > > them. Sorry for any breakage I may have caused. > > At least the OMAP code should not be affected by the bug, that you have with the > pxa-ssp. I think the bug could be also fixed within the pxa code, since the > whole thing goes down to inconsistent memory management within the pxa code. Maybe OMAP is not affected, but I've seen other platforms that also use this dma_data pointer at many more other callbacks and the code seems to believe the pointer is still set to what has been given in the hw_param call (think it was S6000). > Having said that, I do think having separate dma_data for each streams is a > really good idea. > One thing that I can think of in OMAP case, where this could fix a nasty race > condition is (have never seen it, but it is in theory possible): > Also in duplex case, when the second hw_param gets called after the first > omap_mcbsp_hw_params, and before the omap_pcm_hw_params for the first stream. > The second omap_mcbsp_hw_params will override the dma_data, thus we would set > bogus parameters for the first stream. Right. > For the omap-mcbsp.c and omap-pcm.c changes: > Acked-by: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxx> Thanks! > > b/sound/soc/atmel/atmel_ssc_dai.c index e588e63..0b59806 100644 > > --- a/sound/soc/atmel/atmel_ssc_dai.c > > +++ b/sound/soc/atmel/atmel_ssc_dai.c > > @@ -363,12 +363,12 @@ static int atmel_ssc_hw_params(struct > > snd_pcm_substream *substream, ssc_p->dma_params[dir] = dma_params; > > > > /* > > - * The cpu_dai->dma_data field is only used to communicate the > > - * appropriate DMA parameters to the pcm driver hw_params() > > + * The snd_soc_pcm_stream->dma_data field is only used to > > communicate + * the appropriate DMA parameters to the pcm driver > > hw_params() * function. It should not be used for other purposes > > * as it is common to all substreams. > > */ > > - rtd->dai->cpu_dai->dma_data = dma_params; > > + snd_soc_dai_set_dma_data(rtd->dai->cpu_dai, substream, dma_params); > > > > channels = params_channels(params); > > > > diff --git a/sound/soc/davinci/davinci-i2s.c > > b/sound/soc/davinci/davinci-i2s.c index 6362ca0..4aad7ec 100644 > > --- a/sound/soc/davinci/davinci-i2s.c > > +++ b/sound/soc/davinci/davinci-i2s.c > > @@ -585,7 +585,8 @@ static int davinci_i2s_probe(struct platform_device > > *pdev) dev->dma_params[SNDRV_PCM_STREAM_CAPTURE].channel = res->start; > > > > davinci_i2s_dai.private_data = dev; > > - davinci_i2s_dai.dma_data = dev->dma_params; > > + davinci_i2s_dai.capture.dma_data = dev->dma_params; > > + davinci_i2s_dai.playback.dma_data = dev->dma_params; > > Would not be more consistent around the places to actually use the > snd_soc_dai_set_dma_data(...); > function instead of direct assignment here, and there randomly? Sure. Now that this is possible, the davinvi code should be cleaned up. But as I say - I couldn't even compile-test these changes, so I didn't want to break the code flow logic as well. Davinci is special though, other drivers should be more consistent. Daniel _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
