ASoC: sgtl5000: prevent playback to be muted when terminating concurrent capture

When a sound capture/playback is terminated while a playback/capture
is running, power_vag_event() will clear SGTL5000_CHIP_ANA_POWER in
the SND_SOC_DAPM_PRE_PMD event, thus muting the respective other
channel.

Don't clear SGTL5000_CHIP_ANA_POWER when both DAC and ADC are active
to prevent this.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 13 insertions, 3 deletions

diff --git a/sound/soc/codecs/sgtl5000.c b/sound/soc/codecs/sgtl5000.c
index 6c8a9e7bee25..9303c7d011b2 100644
--- a/sound/soc/codecs/sgtl5000.c
+++ b/sound/soc/codecs/sgtl5000.c
@@ -153,6 +153,8 @@ static int mic_bias_event(struct snd_soc_dapm_widget *w,
 static int power_vag_event(struct snd_soc_dapm_widget *w,
         struct snd_kcontrol *kcontrol, int event)
 {
+        const u32 mask = SGTL5000_DAC_POWERUP | SGTL5000_ADC_POWERUP;
+
         switch (event) {
         case SND_SOC_DAPM_POST_PMU:
                 snd_soc_update_bits(w->codec, SGTL5000_CHIP_ANA_POWER,
@@ -160,9 +162,17 @@ static int power_vag_event(struct snd_soc_dapm_widget *w,
                 break;
 
         case SND_SOC_DAPM_PRE_PMD:
-                snd_soc_update_bits(w->codec, SGTL5000_CHIP_ANA_POWER,
-                        SGTL5000_VAG_POWERUP, 0);
-                msleep(400);
+                /*
+                 * Don't clear VAG_POWERUP, when both DAC and ADC are
+                 * operational to prevent inadvertently starving the
+                 * other one of them.
+                 */
+                if ((snd_soc_read(w->codec, SGTL5000_CHIP_ANA_POWER) &
+                                mask) != mask) {
+                        snd_soc_update_bits(w->codec, SGTL5000_CHIP_ANA_POWER,
+                                SGTL5000_VAG_POWERUP, 0);
+                        msleep(400);
+                }
                 break;
         default:
                 break;