[lkml]   [2019]   [Jan]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH v3 2/4] ASoC: add fsl_audmix DT binding documentation
Add the DT binding documentation for NXP Audio Mixer
CPU DAI driver.

Signed-off-by: Viorel Suman <>
.../devicetree/bindings/sound/fsl,audmix.txt | 50 ++++++++++++++++++++++
1 file changed, 50 insertions(+)
create mode 100644 Documentation/devicetree/bindings/sound/fsl,audmix.txt

diff --git a/Documentation/devicetree/bindings/sound/fsl,audmix.txt b/Documentation/devicetree/bindings/sound/fsl,audmix.txt
new file mode 100644
index 0000000..840b7e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/fsl,audmix.txt
@@ -0,0 +1,50 @@
+NXP Audio Mixer (AUDMIX).
+The Audio Mixer is a on-chip functional module that allows mixing of two
+audio streams into a single audio stream. Audio Mixer has two input serial
+audio interfaces. These are driven by two Synchronous Audio interface
+modules (SAI). Each input serial interface carries 8 audio channels in its
+frame in TDM manner. Mixer mixes audio samples of corresponding channels
+from two interfaces into a single sample. Before mixing, audio samples of
+two inputs can be attenuated based on configuration. The output of the
+Audio Mixer is also a serial audio interface. Like input interfaces it has
+the same TDM frame format. This output is used to drive the serial DAC TDM
+interface of audio codec and also sent to the external pins along with the
+receive path of normal audio SAI module for readback by the CPU.
+The output of Audio Mixer can be selected from any of the three streams
+ - serial audio input 1
+ - serial audio input 2
+ - mixed audio
+Mixing operation is independent of audio sample rate but the two audio
+input streams must have same audio sample rate with same number of channels
+in TDM frame to be eligible for mixing.
+Device driver required properties:
+ - compatible : Compatible list, contains "fsl,imx8qm-audmix"
+ - reg : Offset and length of the register set for the device.
+ - clocks : Must contain an entry for each entry in clock-names.
+ - clock-names : Must include the "ipg" for register access.
+ - power-domains : Must contain the phandle to AUDMIX power domain node
+ - dais : Must contain a list of phandles to AUDMIX connected
+ DAIs. The current implementation requires two phandles
+ to SAI interfaces to be provided, the first SAI in the
+ list being used to route the AUDMIX output.
+Device driver configuration example:
+ audmix: audmix@59840000 {
+ compatible = "fsl,imx8qm-audmix";
+ reg = <0x0 0x59840000 0x0 0x10000>;
+ clocks = <&clk IMX8QXP_AUD_AUDMIX_IPG>;
+ clock-names = "ipg";
+ power-domains = <&pd_audmix>;
+ dais = <&sai4>, <&sai5>;
+ };
 \ /
  Last update: 2019-01-17 13:47    [W:0.116 / U:3.740 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site