Re: [PATCH v2 2/7] dt-bindings: soundwire: qcom: add 16-bit sample interval

From: Srinivas Kandagatla
Date: Thu Apr 13 2023 - 07:12:28 EST




On 12/04/2023 17:16, Krzysztof Kozlowski wrote:
On 12/04/2023 17:28, Srinivas Kandagatla wrote:


On 03/04/2023 14:24, Krzysztof Kozlowski wrote:
The port sample interval was always 16-bit, split into low and high
bytes. This split was unnecessary, although harmless for older devices
because all of them used only lower byte (so values < 0xff). With
support for Soundwire controller on Qualcomm SM8550 and its devices,
both bytes will be used, thus add a new 'qcom,ports-sinterval' property
to allow 16-bit sample intervals.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
---
.../bindings/soundwire/qcom,soundwire.yaml | 22 +++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/soundwire/qcom,soundwire.yaml b/Documentation/devicetree/bindings/soundwire/qcom,soundwire.yaml
index c283c594fb5c..883b8be9be1b 100644
--- a/Documentation/devicetree/bindings/soundwire/qcom,soundwire.yaml
+++ b/Documentation/devicetree/bindings/soundwire/qcom,soundwire.yaml
@@ -86,7 +86,7 @@ properties:
qcom,ports-sinterval-low:
$ref: /schemas/types.yaml#/definitions/uint8-array
description:
- Sample interval low of each data port.
+ Sample interval (only lowest byte) of each data port.
Out ports followed by In ports. Used for Sample Interval calculation.
Value of 0xff indicates that this option is not implemented
or applicable for the respective data port.
@@ -94,6 +94,19 @@ properties:
minItems: 3
maxItems: 16
+ qcom,ports-sinterval:
+ $ref: /schemas/types.yaml#/definitions/uint32-array

Should this not be ref: /schemas/types.yaml#/definitions/uint16-array ?

Same answer as for Rob:

Because I am afraid it will grow in next version to 24 or 32 bits. I can
change easily maximum, but if I put here uint16-array, all DTS will have
/bytes 16/ annotation.

As per MiPi Specs the sample Interval is an integer in the range 2 to 65535. I don't see a value in making this u32, other than adding some confusion by deviating from specs.

--srini

Best regards,
Krzysztof