[v4,2/3] ASoC: add fsl_audmix DT binding documentation

Commit Message

Viorel Suman Jan. 22, 2019, 11:14 a.m. UTC

Add the DT binding documentation for NXP Audio Mixer
CPU DAI driver.

Signed-off-by: Viorel Suman <[e-mail]>
---
 .../devicetree/bindings/sound/fsl,audmix.txt       | 54 ++++++++++++++++++++++
 1 file changed, 54 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/sound/fsl,audmix.txt

Comments

Nicolin Chen Jan. 25, 2019, 7:43 p.m. UTC | #1

On Tue, Jan 22, 2019 at 11:14:27AM +0000, Viorel Suman wrote:
> Add the DT binding documentation for NXP Audio Mixer
> CPU DAI driver.
> 
> Signed-off-by: Viorel Suman <[e-mail]>
> ---
>  .../devicetree/bindings/sound/fsl,audmix.txt       | 54 ++++++++++++++++++++++
>  1 file changed, 54 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..45f807e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/sound/fsl,audmix.txt
> @@ -0,0 +1,54 @@
> +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.
> +
> +  - model		: Must contain machine driver name which will configure
> +			  and instantiate the appropriate audio card.

I don't feel this is necessary for DT node. The driver should be
able to figure out a proper name for the machine driver: it could
use the compatible string to get "imx8qm-audmix" as the name like
fsl_ssi; Or it could have built-in "imx-audmix" of_device_id data
corresponding to "fsl,imx8qm-audmix" compatible string -- for any
non-imx compatible in the future, use something else.

Thanks
Nic

> +
> +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>;
> +    model = "imx-audmix";
> +  };
> -- 
> 2.7.4
>

Rob Herring Jan. 30, 2019, 4:32 p.m. UTC | #2

On Fri, Jan 25, 2019 at 11:43:16AM -0800, Nicolin Chen wrote:
> On Tue, Jan 22, 2019 at 11:14:27AM +0000, Viorel Suman wrote:
> > Add the DT binding documentation for NXP Audio Mixer
> > CPU DAI driver.
> > 
> > Signed-off-by: Viorel Suman <[e-mail]>
> > ---
> >  .../devicetree/bindings/sound/fsl,audmix.txt       | 54 ++++++++++++++++++++++
> >  1 file changed, 54 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..45f807e
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/sound/fsl,audmix.txt
> > @@ -0,0 +1,54 @@
> > +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.
> > +
> > +  - model		: Must contain machine driver name which will configure
> > +			  and instantiate the appropriate audio card.
> 
> I don't feel this is necessary for DT node. The driver should be
> able to figure out a proper name for the machine driver: it could
> use the compatible string to get "imx8qm-audmix" as the name like
> fsl_ssi; Or it could have built-in "imx-audmix" of_device_id data
> corresponding to "fsl,imx8qm-audmix" compatible string -- for any
> non-imx compatible in the future, use something else.

I tend to agree, but either way:

Rob Herring <[e-mail]>

Patch

diff --git a/Documentation/devicetree/bindings/sound/fsl,audmix.txt b/Documentation/devicetree/bindings/sound/fsl,audmix.txt
new file mode 100644
index 0000000..45f807e
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/fsl,audmix.txt
@@ -0,0 +1,54 @@ 
+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.
+
+  - model		: Must contain machine driver name which will configure
+			  and instantiate the appropriate audio card.
+
+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>;
+    model = "imx-audmix";
+  };