Hi Liam, Can you please look at this mail Thread. http://mailman.alsa-project.org/pipermail/alsa-devel/2007-June/001436.html On 6/12/07, Liam Girdwood <lg@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > On Tue, 2007-06-12 at 17:44 +0530, Nobin Mathew wrote: > > Liam > > > > I am trying to implement shutdown in ASoC > > > > /* dapm stream operations */ > > #define SND_SOC_DAPM_STREAM_NOP 0x0 > > #define SND_SOC_DAPM_STREAM_START 0x1 > > #define SND_SOC_DAPM_STREAM_STOP 0x2 > > #define SND_SOC_DAPM_STREAM_SUSPEND 0x4 > > #define SND_SOC_DAPM_STREAM_RESUME 0x8 > > #define SND_SOC_DAPM_STREAM_PAUSE_PUSH 0x10 > > #define SND_SOC_DAPM_STREAM_PAUSE_RELEASE 0x20 > > > > > > Is there any need to add stream operation called > > SND_SOC_DAPM_STREAM_SHUTDOWN even though this has no effect no the > > system behaviour. > > > > Instead we can use SND_SOC_DAPM_STREAM_SUSPEND. > > Is this OK. > > > > is there any better way to implement suspend?, i think suspend will be > > a copy of remove() function. > > > > I assume your looking to shutdown the codec to a low power state without > removing the driver ? > > If so, SND_SOC_DAPM_STREAM_* operations all act upon stream and path > based widgets (stream and path domain from soc-dapm.h). That is, they > will always power up/down widgets that are actively used in the playback > or capture of audio. This happens automatically at the end of > playback/capture. The wont power down the codec domain. > > Atm, the codec power domain (VRef, Vmid) is only affected by signalling > a dapm device event. This happens at probe/remove and suspend/resume atm > for most codecs, although some codecs can alter their Vmid/Vref settings > as part of stream/path domain power changes (as above, e.g. WM8753 > changes Vmid from 50k @ SNDRV_CTL_POWER_D0 to 500k SNDRV_CTL_POWER_D3) > > Fwiw, I've already added the shutdown function in the new ppc-dev > branch. All component drivers will contain a struct device_driver and > inherit it's features. More on this later today, for the moment the > latest soc.h is here :- > > http://opensource.wolfsonmicro.com/cgi-bin/gitweb/gitweb.cgi?p=linux-2.6-asoc;a=blob_plain;f=include/sound/soc.h;hb=ppc-dev > > and pxa-i2s driver is here fyi :- > > http://opensource.wolfsonmicro.com/cgi-bin/gitweb/gitweb.cgi?p=linux-2.6-asoc;a=blob_plain;f=sound/soc/pxa/pxa2xx-i2s.c;hb=ppc-dev > > > Liam > > > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
