On Tue, Feb 23, 2010 at 06:10:42PM -0600, Olaya, Margarita wrote:
Currently, handsfree DAC and driver are the only components that can prevent codec to enter to low-power playback mode. Other components like earphone driver, vibrator driver or loopback (which are not yet supported in the driver) can cause the same effect.
Hrm, this vibrator is raising a red flag for me with the MFD patch - it sounds like we'll need to have an equivalent of the twl4030-codec MFD for the TWL6030 to support the vibrator since that doesn't fit within the audio subsystem.
In order to detect conflicting paths, CODEC driver supervises non-low-power widgets powered by DAPM mechanism, just at the point pcm trigger callback gets called.
+static int twl6030_power_mode_event(struct snd_soc_dapm_widget *w,
struct snd_kcontrol *kcontrol, int event)+{
- struct snd_soc_codec *codec = w->codec;
- struct twl6030_data *priv = codec->private_data;
- if (SND_SOC_DAPM_EVENT_ON(event))
priv->non_lp++;- else
priv->non_lp--;- return 0;
+}
So what happens if we're already in low power mode and non_lp gets set (or conversely but less seriously, if we get to the point where we can enter low power mode)?
- switch (cmd) {
- case SNDRV_PCM_TRIGGER_START:
/** low-power playback mode is restricted* for headset path only*/if ((priv->sysclk == 17640000) && priv->non_lp) {dev_err(codec->dev,"some enabled paths aren't supported at %dHz\n",priv->sysclk);return -EPERM;}break;
Should probably do this for all the startup trigger sources - _RESUME for example.