Messages in this thread | | | Date | Wed, 02 Jul 2014 16:24:46 +0200 | From | Takashi Iwai <> | Subject | Re: [alsa-devel] [PATCH v2 3/5] ASoC: generic-dmaengine-pcm: Prepare formats mask for valid physical sample sizes |
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At Wed, 02 Jul 2014 16:13:59 +0200, Lars-Peter Clausen wrote: > > On 07/02/2014 04:12 PM, Takashi Iwai wrote: > > At Wed, 02 Jul 2014 16:10:09 +0200, > > Lars-Peter Clausen wrote: > >> > >> On 07/02/2014 03:47 PM, Takashi Iwai wrote: > >> [...] > >>>> + /* > >>>> + * Prepare formats mask for valid/allowed sample types. If the dma does > >>>> + * not have support for the given physical word size, it needs to be > >>>> + * masked out so user space can not use the format which produces > >>>> + * corrupted audio. > >>>> + * In case the dma driver does not implement the slave_caps the default > >>>> + * assumption is that it supports 1, 2 and 4 bytes widths. > >>>> + */ > >>>> + for (i = 0; i <= SNDRV_PCM_FORMAT_LAST; i++) { > >>>> + int bits = snd_pcm_format_physical_width(i); > >>> > >>> Better to add a negative value check. Some formats return -EINVAL. > >>> > >> > >> So what should we do with those formats? Not support them? > > > > Yes, these are special formats that can't be handled generically. > > > > Looking through the list in pcm_misc.c there are also some formats where the > physical width is not a multiple of 8. We should probably also skip those.
Right, ADPCM and G723 are such ones.
Takashi
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