On 7/21/21 9:03 AM, Maxime Ripard wrote:

Bluetooth SCO Link are supported by Linux with a matching device tree binding.

Now that we have the DT validation in place, let's convert the device tree bindings for that driver over to a YAML schema.

The value expected for #sound-dai-cells wasn't documented though, and the users were inconsistent. The example didn't list it, and across the 4 users we have in tree:

• 1 had a cells value of 1, but using only 0 as argument
• 1 had a cells value of 0,
• 2 didn't have this property at all, behaving as if it was 0,

It seems like the consensus seems to be that it should be 0, so let's enforce it.

The driver has two DAIs: "bt-sco-pcm" and "bt-sco-pcm-wb". If #sound-dai-cells is 0, only the first DAI can be referenced from a device tree. So to declare support for wideband PCM, or explicitly declare a lack of support for it, #sound-dai-cells must be 1.

Regards, Samuel

Cc: alsa-devel@alsa-project.org Cc: devicetree@vger.kernel.org Cc: Liam Girdwood lgirdwood@gmail.com Cc: Mark Brown broonie@kernel.org Cc: Samuel Holland samuel@sholland.org Signed-off-by: Maxime Ripard maxime@cerno.tech

---

.../devicetree/bindings/sound/bt-sco.txt | 13 ------- .../bindings/sound/linux,bt-sco.yaml | 34 +++++++++++++++++++ 2 files changed, 34 insertions(+), 13 deletions(-) delete mode 100644 Documentation/devicetree/bindings/sound/bt-sco.txt create mode 100644 Documentation/devicetree/bindings/sound/linux,bt-sco.yaml

diff --git a/Documentation/devicetree/bindings/sound/bt-sco.txt b/Documentation/devicetree/bindings/sound/bt-sco.txt deleted file mode 100644 index 641edf75e184..000000000000 --- a/Documentation/devicetree/bindings/sound/bt-sco.txt +++ /dev/null @@ -1,13 +0,0 @@ -Bluetooth-SCO audio CODEC

-This device support generic Bluetooth SCO link.

-Required properties:

• • compatible : "delta,dfbmcs320" or "linux,bt-sco"

-Example:

-codec: bt_sco {

• compatible = "delta,dfbmcs320";

-}; diff --git a/Documentation/devicetree/bindings/sound/linux,bt-sco.yaml b/Documentation/devicetree/bindings/sound/linux,bt-sco.yaml new file mode 100644 index 000000000000..334b508205cd --- /dev/null +++ b/Documentation/devicetree/bindings/sound/linux,bt-sco.yaml @@ -0,0 +1,34 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/sound/linux,bt-sco.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml#

+title: Bluetooth SCO Audio Codec Device Tree Bindings

+maintainers:

• • Mark Brown broonie@kernel.org

+properties:

• '#sound-dai-cells':
• const: 0
• compatible:
• enum:

•  - delta,dfbmcs320
  

•  - linux,bt-sco
  

+required:

• • '#sound-dai-cells'
• • compatible

+additionalProperties: false

+examples:

• • |
• codec {

•    #sound-dai-cells = <0>;
  

•    compatible = "linux,bt-sco";
  

• };

+...