[alsa-devel] [PATCH 2/3] ASoC: Blackfin: add multi-channel supporting in Blackfin ASoC driver and AD1980 codec driver
Cliff.Cai at analog.com
Tue Oct 21 11:08:31 CEST 2008
>From: Mark Brown [mailto:broonie at sirena.org.uk]
>Sent: Tuesday, October 21, 2008 4:37 PM
>To: Bryan Wu
>Cc: alsa-devel at alsa-project.org; Cliff Cai
>Subject: Re: [PATCH 2/3] ASoC: Blackfin: add multi-channel
>supporting in Blackfin ASoC driver and AD1980 codec driver
>On Tue, Oct 21, 2008 at 11:36:12AM +0800, Bryan Wu wrote:
>> +config SND_MULTICHAN_SUPPORT
>> + bool "Enable Multichannel Support"
>> + depends on SND_BF5XX_AC97
>> + default n
>> + help
>> + Say y if you want AC97 driver to support up to 5.1
>> + this mode will consume much more memory for DMA.
>Should this be a user visible option or selected by the
I think people want to enable this feature
Only If they really want it,since it will consume much more memory
To hold multi-channel data.
>To be honest, I'm surprised that the multi-channel support
>can't only incur the extra memory consumpton when playing back
>a multi-channel stream - I'd have expected the hardware to
>work in the same way for a normal stereo stream even if
>multi-channel support is built in.
Yes,hardware almost works in the same way as playing a stereo
That it need to fill more data to DMA memory manually,since we just
Controller using serial port.
>> -void bf5xx_ac97_to_pcm(const struct ac97_frame *src, __u32 *dst, \
>> +void bf5xx_ac97_to_pcm(const struct ac97_frame *src, __u16 *dst, \
>> size_t count)
>Separately please submit a patch removing the needless
>continuation character here.
>> diff --git a/sound/soc/codecs/ad1980.c b/sound/soc/codecs/ad1980.c
>> index 1397b8e..e22fbdf 100644
>> --- a/sound/soc/codecs/ad1980.c
>> +++ b/sound/soc/codecs/ad1980.c
>The codec driver changes should be submitted as a separate patch.
>They're good to go as-is.
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