2022-12-29 10:19:09

by Jung Daehwan

[permalink] [raw]
Subject: [RFC PATCH v2 3/3] dt-bindings: usb: snps,dwc3: add generic-xhci as child

Currently, dwc3 invokes just xhci platform driver(generic-xhci) without
DT schema even though xhci works as child of dwc3. It makes sense to add
xhci as child of dwc3 with DT schema. It also supports to use another
compatible in xhci platform driver.

Signed-off-by: Daehwan Jung <[email protected]>
---
.../devicetree/bindings/usb/snps,dwc3.yaml | 29 +++++++++++++++++++
1 file changed, 29 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
index 6d78048c4613..83ed7c526dba 100644
--- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
@@ -360,8 +360,22 @@ properties:
description:
Enable USB remote wakeup.

+ "#address-cells":
+ enum: [ 1, 2 ]
+
+ "#size-cells":
+ enum: [ 1, 2 ]
+
+ ranges: true
+
unevaluatedProperties: false

+# Required child node:
+patternProperties:
+ "^usb@[0-9a-f]+$":
+ $ref: generic-xhci.yaml#
+ description: Required child node
+
required:
- compatible
- reg
@@ -388,4 +402,19 @@ examples:
snps,dis_u2_susphy_quirk;
snps,dis_enblslpm_quirk;
};
+ - |
+ usb@4a200000 {
+ compatible = "snps,dwc3";
+ reg = <0x4a200000 0xcfff>;
+ interrupts = <0 92 4>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ xhci: usb@4a200000 {
+ compatible = "generic-xhci";
+ reg = <0x4a200000 0x7fff>;
+ interrupts = <0 92 4>;
+ };
+ };
...
--
2.31.1


2022-12-29 10:43:37

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [RFC PATCH v2 3/3] dt-bindings: usb: snps,dwc3: add generic-xhci as child

On 29/12/2022 10:57, Daehwan Jung wrote:
> Currently, dwc3 invokes just xhci platform driver(generic-xhci) without
> DT schema even though xhci works as child of dwc3. It makes sense to add
> xhci as child of dwc3 with DT schema. It also supports to use another
> compatible in xhci platform driver.

You use some driver as an argument for hardware description, which is
not what we need. Describe the hardware.

>
> Signed-off-by: Daehwan Jung <[email protected]>
> ---
> .../devicetree/bindings/usb/snps,dwc3.yaml | 29 +++++++++++++++++++
> 1 file changed, 29 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> index 6d78048c4613..83ed7c526dba 100644
> --- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> +++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> @@ -360,8 +360,22 @@ properties:
> description:
> Enable USB remote wakeup.
>
> + "#address-cells":
> + enum: [ 1, 2 ]
> +
> + "#size-cells":
> + enum: [ 1, 2 ]
> +
> + ranges: true
> +
> unevaluatedProperties: false
>
> +# Required child node:
> +patternProperties:
> + "^usb@[0-9a-f]+$":
> + $ref: generic-xhci.yaml#
> + description: Required child node

DWC does not have another piece of controller as child... DWC is the
controller. Not mentioning that you now affect several other devices
without describing the total hardware picture (just some drivers which
is not that relevant).

> +
> required:
> - compatible
> - reg
> @@ -388,4 +402,19 @@ examples:
> snps,dis_u2_susphy_quirk;
> snps,dis_enblslpm_quirk;
> };
> + - |
> + usb@4a200000 {
> + compatible = "snps,dwc3";
> + reg = <0x4a200000 0xcfff>;
> + interrupts = <0 92 4>;
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges;
> +
> + xhci: usb@4a200000 {
> + compatible = "generic-xhci";

There are no such device...

> + reg = <0x4a200000 0x7fff>;
> + interrupts = <0 92 4>;
> + };
> + };
> ...

Best regards,
Krzysztof

2022-12-30 16:35:33

by Rob Herring (Arm)

[permalink] [raw]
Subject: Re: [RFC PATCH v2 3/3] dt-bindings: usb: snps,dwc3: add generic-xhci as child


On Thu, 29 Dec 2022 18:57:46 +0900, Daehwan Jung wrote:
> Currently, dwc3 invokes just xhci platform driver(generic-xhci) without
> DT schema even though xhci works as child of dwc3. It makes sense to add
> xhci as child of dwc3 with DT schema. It also supports to use another
> compatible in xhci platform driver.
>
> Signed-off-by: Daehwan Jung <[email protected]>
> ---
> .../devicetree/bindings/usb/snps,dwc3.yaml | 29 +++++++++++++++++++
> 1 file changed, 29 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/dt-review-ci/linux/Documentation/devicetree/bindings/usb/snps,dwc3.example.dtb: usb@4a200000: #size-cells:0:0: 0 was expected
From schema: /builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/usb/snps,dwc3.yaml

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/[email protected]

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

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 after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

2023-01-03 19:51:27

by Rob Herring (Arm)

[permalink] [raw]
Subject: Re: [RFC PATCH v2 3/3] dt-bindings: usb: snps,dwc3: add generic-xhci as child

On Mon, Jan 02, 2023 at 02:45:17PM +0900, Jung Daehwan wrote:
> On Thu, Dec 29, 2022 at 11:23:02AM +0100, Krzysztof Kozlowski wrote:
> > On 29/12/2022 10:57, Daehwan Jung wrote:
> > > Currently, dwc3 invokes just xhci platform driver(generic-xhci) without
> > > DT schema even though xhci works as child of dwc3. It makes sense to add
> > > xhci as child of dwc3 with DT schema. It also supports to use another
> > > compatible in xhci platform driver.
> >
> > You use some driver as an argument for hardware description, which is
> > not what we need. Describe the hardware.
> >
>
> OK. I will it on next submission.
>
> > >
> > > Signed-off-by: Daehwan Jung <[email protected]>
> > > ---
> > > .../devicetree/bindings/usb/snps,dwc3.yaml | 29 +++++++++++++++++++
> > > 1 file changed, 29 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> > > index 6d78048c4613..83ed7c526dba 100644
> > > --- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> > > +++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
> > > @@ -360,8 +360,22 @@ properties:
> > > description:
> > > Enable USB remote wakeup.
> > >
> > > + "#address-cells":
> > > + enum: [ 1, 2 ]
> > > +
> > > + "#size-cells":
> > > + enum: [ 1, 2 ]
> > > +
> > > + ranges: true
> > > +
> > > unevaluatedProperties: false
> > >
> > > +# Required child node:
> > > +patternProperties:
> > > + "^usb@[0-9a-f]+$":
> > > + $ref: generic-xhci.yaml#
> > > + description: Required child node
> >
> > DWC does not have another piece of controller as child... DWC is the
> > controller. Not mentioning that you now affect several other devices
> > without describing the total hardware picture (just some drivers which
> > is not that relevant).
> >
>
> DWC controller supports USB Host mode and it uses same resource and
> really works as a child. I guess it's same on many SOCs, especially
> mobile..

Yes, and we already support all those platforms just fine without this
child node. Adding it means we have to then support *both* ways in the
driver.


> I just want to modify it to work with DT schema (dwc3 -> xhci-plat).
> I think it needs to dicuss more..

Why doesn't it work with the schema?

It's convenient when DT nodes == device drivers, but hardware is messy
sometimes. Linux (and other OSs) have to deal with that. We can't write
the DT to reflect the current (and evolving) needs of a particular OS.

Rob