From: Shawn Guo shawn.guo@linaro.org
It's basically the result of discussion around how external amplifier controlled by GPIO should be supported by audio card, that uses generic machine driver like audio-graph-card.
The patch series updates audio-graph-card bindings and driver to support DAPM widget and audio routing, and then based on that, creates an output driver widget with event to control the amplifier via GPIO.
[1] https://www.spinics.net/lists/arm-kernel/msg589717.html
Shawn Guo (2): ASoC: audio-graph-card: update bindings for amplifier support ASoC: audio-graph-card: add widgets and routing for external amplifier support
.../devicetree/bindings/sound/audio-graph-card.txt | 5 +++ sound/soc/generic/audio-graph-card.c | 48 +++++++++++++++++++++- 2 files changed, 52 insertions(+), 1 deletion(-)