Add documentation about new dts bindings following new support
for compatible "fsl,imx-audio-generic".
Some CPU DAI don't require a real audio codec. The new compatible
"fsl,imx-audio-generic" allows using the driver with codec drivers
SPDIF DIT and SPDIF DIR as dummy codecs.
It also allows using not pre-configured audio codecs which
don't require specific control through a codec driver.
The new dts properties give the possibility to set some parameters
about the CPU DAI usually set through the codec configuration.
Signed-off-by: Elinor Montmasson <[email protected]>
Co-authored-by: Philip-Dylan Gleonec <[email protected]>
---
.../bindings/sound/fsl-asoc-card.txt | 28 ++++++++++++++++++-
1 file changed, 27 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt b/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
index 4e8dbc5abfd1..f137ef2154e3 100644
--- a/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
+++ b/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
@@ -17,6 +17,9 @@ Note: The card is initially designed for those sound cards who use AC'97, I2S
and PCM DAI formats. However, it'll be also possible to support those non
AC'97/I2S/PCM type sound cards, such as S/PDIF audio and HDMI audio, as
long as the driver has been properly upgraded.
+ To use CPU DAIs that do not require a codec such as an S/PDIF controller,
+ or to use a DAI to output or capture raw I2S/TDM data, you can
+ use the compatible "fsl,imx-audio-generic".
The compatible list for this generic sound card currently:
@@ -48,6 +51,8 @@ The compatible list for this generic sound card currently:
"fsl,imx-audio-nau8822"
+ "fsl,imx-audio-generic"
+
Required properties:
- compatible : Contains one of entries in the compatible list.
@@ -56,7 +61,11 @@ Required properties:
- audio-cpu : The phandle of an CPU DAI controller
- - audio-codec : The phandle of an audio codec
+ - audio-codec : The phandle of an audio codec.
+ If using the "fsl,imx-audio-generic" compatible,
+ give instead a pair of phandles with the
+ spdif_transmitter first (driver SPDIF DIT) and the
+ spdif_receiver second (driver SPDIF DIR).
Optional properties:
@@ -87,6 +96,23 @@ Optional properties:
- frame-inversion : dai-link uses frame clock inversion, for details see simple-card.yaml.
- bitclock-inversion : dai-link uses bit clock inversion, for details see simple-card.yaml.
- mclk-id : main clock id, specific for each card configuration.
+ For multi-codec configurations, an array of ids can be
+ given, one for each codec.
+
+Optional, relevant only with the "fsl,imx-audio-generic" compatible:
+
+ - cpu-slot-width : Indicates a specific TDM slot width in bits.
+ - cpu-slot-num : Indicates a specific number of TDM slots per frame.
+
+ - cpu-sysclk-freq-rx : Frequency of the CPU DAI sys clock for Rx.
+ - cpu-sysclk-freq-tx : Frequency of the CPU DAI sys clock for Tx.
+
+ - cpu-sysclk-dir-rx-out : Boolean property. Specifies sys clock direction
+ as 'out' on initialization for Rx.
+ If not set, default direction is 'in'.
+ - cpu-sysclk-dir-tx-out : Boolean property. Specifies sys clock direction
+ as 'out' on initialization for Tx.
+ If not set, default direction is 'in'.
Optional unless SSI is selected as a CPU DAI:
--
2.25.1
On Mon, Dec 18, 2023 at 01:40:58PM +0100, Elinor Montmasson wrote:
> Add documentation about new dts bindings following new support
> for compatible "fsl,imx-audio-generic".
>
> Some CPU DAI don't require a real audio codec. The new compatible
> "fsl,imx-audio-generic" allows using the driver with codec drivers
> SPDIF DIT and SPDIF DIR as dummy codecs.
> It also allows using not pre-configured audio codecs which
> don't require specific control through a codec driver.
>
> The new dts properties give the possibility to set some parameters
> about the CPU DAI usually set through the codec configuration.
>
> Signed-off-by: Elinor Montmasson <[email protected]>
> Co-authored-by: Philip-Dylan Gleonec <[email protected]>
> ---
> .../bindings/sound/fsl-asoc-card.txt | 28 ++++++++++++++++++-
> 1 file changed, 27 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt b/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
> index 4e8dbc5abfd1..f137ef2154e3 100644
> --- a/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
> +++ b/Documentation/devicetree/bindings/sound/fsl-asoc-card.txt
> @@ -17,6 +17,9 @@ Note: The card is initially designed for those sound cards who use AC'97, I2S
> and PCM DAI formats. However, it'll be also possible to support those non
> AC'97/I2S/PCM type sound cards, such as S/PDIF audio and HDMI audio, as
> long as the driver has been properly upgraded.
> + To use CPU DAIs that do not require a codec such as an S/PDIF controller,
> + or to use a DAI to output or capture raw I2S/TDM data, you can
> + use the compatible "fsl,imx-audio-generic".
>
>
> The compatible list for this generic sound card currently:
> @@ -48,6 +51,8 @@ The compatible list for this generic sound card currently:
>
> "fsl,imx-audio-nau8822"
>
> + "fsl,imx-audio-generic"
> +
> Required properties:
>
> - compatible : Contains one of entries in the compatible list.
> @@ -56,7 +61,11 @@ Required properties:
>
> - audio-cpu : The phandle of an CPU DAI controller
>
> - - audio-codec : The phandle of an audio codec
> + - audio-codec : The phandle of an audio codec.
> + If using the "fsl,imx-audio-generic" compatible,
> + give instead a pair of phandles with the
> + spdif_transmitter first (driver SPDIF DIT) and the
> + spdif_receiver second (driver SPDIF DIR).
>
> Optional properties:
>
> @@ -87,6 +96,23 @@ Optional properties:
> - frame-inversion : dai-link uses frame clock inversion, for details see simple-card.yaml.
> - bitclock-inversion : dai-link uses bit clock inversion, for details see simple-card.yaml.
> - mclk-id : main clock id, specific for each card configuration.
> + For multi-codec configurations, an array of ids can be
> + given, one for each codec.
> +
> +Optional, relevant only with the "fsl,imx-audio-generic" compatible:
> +
> + - cpu-slot-width : Indicates a specific TDM slot width in bits.
> + - cpu-slot-num : Indicates a specific number of TDM slots per frame.
Pretty sure I've seen other bindings with TDM slot properties. A sign we
need something common if we don't already have something.
> +
> + - cpu-sysclk-freq-rx : Frequency of the CPU DAI sys clock for Rx.
> + - cpu-sysclk-freq-tx : Frequency of the CPU DAI sys clock for Tx.
> +
> + - cpu-sysclk-dir-rx-out : Boolean property. Specifies sys clock direction
> + as 'out' on initialization for Rx.
> + If not set, default direction is 'in'.
> + - cpu-sysclk-dir-tx-out : Boolean property. Specifies sys clock direction
> + as 'out' on initialization for Tx.
> + If not set, default direction is 'in'.
Looks like clock stuff. Use the clock binding.
Rob
Hello,
On Wednesday, 20 December, 2023 23:25:50, Rob Herring wrote:
> On Mon, Dec 18, 2023 at 01:40:58PM +0100, Elinor Montmasson wrote:
> > +Optional, relevant only with the "fsl,imx-audio-generic" compatible:
> > +
> > + - cpu-slot-width : Indicates a specific TDM slot width in bits.
> > + - cpu-slot-num : Indicates a specific number of TDM slots per frame.
>
> Pretty sure I've seen other bindings with TDM slot properties. A sign we
> need something common if we don't already have something.
That's right, "tdm-slot.txt" already defines TDM bindings, I will
use them with the utility function snd_soc_of_parse_tdm_slot().
> > + - cpu-sysclk-freq-rx : Frequency of the CPU DAI sys clock for Rx.
> > + - cpu-sysclk-freq-tx : Frequency of the CPU DAI sys clock for Tx.
> > +
> > + - cpu-sysclk-dir-rx-out : Boolean property. Specifies sys clock direction
> > + as 'out' on initialization for Rx.
> > + If not set, default direction is 'in'.
> > + - cpu-sysclk-dir-tx-out : Boolean property. Specifies sys clock direction
> > + as 'out' on initialization for Tx.
> > + If not set, default direction is 'in'.
>
> Looks like clock stuff. Use the clock binding.
simple-card defines similar properties at the dai level:
"system-clock-frequency" and "system-clock-direction-out".
The first is used if no "clocks" binding is specified for the dai node.
Maybe I could use a similar logic with fsl-asoc-card ?
* adding a "clock-cpu" phandle property which should be the cpu clock.
It will be used to retreive the frequency for both RX and TX.
* keeping "cpu-sysclk-freq-rx"/"cpu-sysclk-freq-tx", which are used if
no clock is provided, like "system-clock-frequency" in simple-card.
* keep using "cpu-sysclk-dir-rx-out"/"cpu-sysclk-dir-tx-out", like
"system-clock-direction-out" in simple card.
Also, maybe I could rename my new properties:
cpu-system-clock-frequency-tx, cpu-system-clock-direction-out-rx, ...
It would better match those in simple-card as they do the same thing.
Best regards,
Elinor Montmasson