McBSP's data delay can be configured from 0 to 2 bit clock periods. 0 is
used for DSP_B format, 1 for DSP_A format. A data delay of 2 bit clock
periods can be used to interface to 'T1 framing' devices where data
stream is preceded by a 'framing bit'. This 2 bit clock data delay is
not described in the bindings.
Add two flags 'ti,T1-framing-[rx/tx]' to enable a data delay of 2
bit clock periods in reception or transmission.
Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
---
.../devicetree/bindings/sound/davinci-mcbsp.yaml | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/Documentation/devicetree/bindings/sound/davinci-mcbsp.yaml b/Documentation/devicetree/bindings/sound/davinci-mcbsp.yaml
index 0c2b1936c6a1..4fa677023827 100644
--- a/Documentation/devicetree/bindings/sound/davinci-mcbsp.yaml
+++ b/Documentation/devicetree/bindings/sound/davinci-mcbsp.yaml
@@ -67,6 +67,20 @@ properties:
"#sound-dai-cells":
const: 0
+ ti,T1-framing-tx:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description:
+ If the property is present, tx data delay is set to 2 bit clock periods.
+ McBSP will insert a blank period (high-impedance period) before the first
+ data bit. This can be used to interface to T1-framing devices.
+
+ ti,T1-framing-rx:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description:
+ If the property is present, rx data delay is set to 2 bit clock periods.
+ McBSP will discard the bit preceding the data stream (called framing bit).
+ This can be used to interface to T1-framing devices.
+
required:
- "#sound-dai-cells"
- compatible
--
2.44.0