[v1,1/2] dt-bindings: msm/dsi: Add 10nm dsi phy tuning properties

Add 10nm dsi phy tuning properties for phy drive strength and
phy drive level adjustemnt.

Signed-off-by: Rajeev Nandan <quic_rajeevny@quicinc.com>
---
 .../devicetree/bindings/display/msm/dsi-phy-10nm.yaml | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

On Thu, 30 Dec 2021 14:54:35 +0530, Rajeev Nandan wrote:
> Add 10nm dsi phy tuning properties for phy drive strength and
> phy drive level adjustemnt.
> 
> Signed-off-by: Rajeev Nandan <quic_rajeevny@quicinc.com>
> ---
>  .../devicetree/bindings/display/msm/dsi-phy-10nm.yaml | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.yaml: properties:phy-drive-strength-cfg:type: 'array' is not one of ['boolean', 'object']
	from schema $id: http://devicetree.org/meta-schemas/core.yaml#
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.yaml: properties:phy-drive-level-cfg:type: 'array' is not one of ['boolean', 'object']
	from schema $id: http://devicetree.org/meta-schemas/core.yaml#
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.yaml: ignoring, error in schema: properties: phy-drive-strength-cfg: type
Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.example.dt.yaml:0:0: /example-0/dsi-phy@ae94400: failed to match any schema with compatible: ['qcom,dsi-phy-10nm']

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/patch/1574124

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit.

Quoting Rajeev Nandan (2021-12-30 01:24:35)
> Add 10nm dsi phy tuning properties for phy drive strength and
> phy drive level adjustemnt.

s/adjustemnt/adjustment/

Please add the details about parasitics and eye shape tuning to this
commit text.

>
> Signed-off-by: Rajeev Nandan <quic_rajeevny@quicinc.com>
> ---
>  .../devicetree/bindings/display/msm/dsi-phy-10nm.yaml | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.yaml b/Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.yaml
> index 4399715..9406982 100644
> --- a/Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.yaml
> +++ b/Documentation/devicetree/bindings/display/msm/dsi-phy-10nm.yaml
> @@ -35,6 +35,18 @@ properties:
>        Connected to DSI0_MIPI_DSI_PLL_VDDA0P9 pin for sc7180 target and
>        connected to VDDA_MIPI_DSI_0_PLL_0P9 pin for sdm845 target
>
> +  phy-drive-strength-cfg:
> +    type: array
> +    description:
> +      Register values of DSIPHY_RESCODE_OFFSET_TOP and DSIPHY_RESCODE_OFFSET_BOT
> +      for all five lanes to adjust the phy drive strength.
> +
> +  phy-drive-level-cfg:
> +    type: array
> +    description:
> +      Register values of DSIPHY_RESCODE_OFFSET_TOP for all five lanes to adjust
> +      phy drive level/amplitude.

It would be better to put human understandable values into DT here. This
looks like a black box to anyone outside of qcom, so they won't know how
to tune or set these register values.

At least for phy-drive-level-cfg it sounds like it could be some sort of
property that is a u32 array of 5 elements for each lane indicating some
sort of amplitude, i.e.

	phy-max-amplitudes = <0 1 2 3 4>;
	phy-min-amplitudes = <0 1 2 3 4>;

where each index corresponds to a particular lane. Then the driver can
parse the amplitude and convert it into some sort of register value.