-----Original Message----- From: Mark Brown [mailto:broonie@sirena.org.uk] Sent: Tuesday, October 21, 2008 4:37 PM To: Bryan Wu Cc: alsa-devel@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 5.1channel audio.
this mode will consume much more memory for DMA.Should this be a user visible option or selected by the machine drivers?
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 stream,except That it need to fill more data to DMA memory manually,since we just simulate AC97 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.