[alsa-devel] [PATCH V5 1/3] ASoC: Alchemy AC97C/I2SC audio support

Manuel Lauss manuel.lauss at googlemail.com
Tue Jul 26 16:43:16 CEST 2011


On Tue, Jul 26, 2011 at 4:31 PM, Mark Brown
<broonie at opensource.wolfsonmicro.com> wrote:
> On Mon, Jul 25, 2011 at 01:44:45PM +0200, Manuel Lauss wrote:
>
> Looks good, I'll apply this but a few minor comments you might want to
> look at incrementally.
>
>> +#define ALCHEMY_PCM_FMTS                                     \
>> +     (SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_U8 |        \
>> +      SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE |    \
>> +      SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_U16_BE |    \
>> +      SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S32_BE |    \
>> +      SNDRV_PCM_FMTBIT_U32_LE | SNDRV_PCM_FMTBIT_U32_BE |    \
>> +      0)
>
> Why the | 0?  Same for the other one.

Old habit in case I need to insert other format bits in the future (then
the second-to-last line need not be changed in a patch).


>> +     case (DMA_D0 | DMA_D1):
>> +             pr_debug("DMA %d missed interrupt.\n", stream->dma);
>> +             au1000_dma_stop(stream);
>> +             au1000_dma_start(stream);
>> +             break;
>> +     case (~DMA_D0 & ~DMA_D1):
>> +             pr_debug("DMA %d empty irq.\n", stream->dma);
>
> This case should return IRQ_NONE really since it didn't handle an
> interrupt...

If that last case ever happens the DMA engine is broken, as it shouldn't
issue interrupts when no transfer is in progress.  The errata sheets don't
mention anything (yet).

Thanks!
        Manuel Lauss
--
To unsubscribe from this list: send the line "unsubscribe alsa-devel" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html



More information about the Alsa-devel mailing list