[alsa-devel] [PATCH] ASoC: Sync initial widget state with hardware

[Mark Brown]

ASoC generally uses the register defaults for everything, but in some
cases the hardware will default to enabling some of the DAPM widgets
(clocks for example). Ensure that DAPM knows about the actual widget
state at initialisation by reading the enable bits after instantiating
the widgets so they don't get left enabled needlessly.

Signed-off-by: Mark Brown <broonie at opensource.wolfsonmicro.com>
---
 sound/soc/soc-dapm.c |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index d0342aa..b4e8755 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -1664,6 +1664,7 @@ EXPORT_SYMBOL_GPL(snd_soc_dapm_add_routes);
 int snd_soc_dapm_new_widgets(struct snd_soc_dapm_context *dapm)
 {
 	struct snd_soc_dapm_widget *w;
+	unsigned int val;
 
 	list_for_each_entry(w, &dapm->card->widgets, list)
 	{
@@ -1712,6 +1713,18 @@ int snd_soc_dapm_new_widgets(struct snd_soc_dapm_context *dapm)
 		case snd_soc_dapm_post:
 			break;
 		}
+
+		/* Read the initial power state from the device */
+		if (w->reg >= 0) {
+			val = snd_soc_read(w->codec, w->reg);
+			val &= 1 << w->shift;
+			if (w->invert)
+				val = !val;
+
+			if (val)
+				w->active = 1;
+		}
+
 		w->new = 1;
 	}
 
-- 
1.7.2.3