Re: [PATCH v3 1/2] dt-bindings: usb: add TUSB73x0 PCIe

[Rob Herring <robh@kernel.org>]

On Fri, Oct 18, 2024 at 12:55:04PM +0200, Francesco Dolcini wrote:
> From: Parth Pancholi <parth.pancholi@toradex.com>
> 
> Add device tree bindings for TI's TUSB73x0 PCIe-to-USB 3.0 xHCI
> host controller. The controller supports software configuration
> through PCIe registers, such as controlling the PWRONx polarity
> via the USB control register (E0h).
> 
> Similar generic PCIe-based bindings can be found as qcom,ath11k-pci.yaml
> as an example.
> 
> Datasheet: https://www.ti.com/lit/ds/symlink/tusb7320.pdf
> Signed-off-by: Parth Pancholi <parth.pancholi@toradex.com>
> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
> ---
> v3: use lowercase hex in compatible
> v2: rename property to ti,tusb7320-pwron-active-high and change type to flag
> ---
>  .../bindings/usb/ti,tusb73x0-pci.yaml         | 60 +++++++++++++++++++
>  1 file changed, 60 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/usb/ti,tusb73x0-pci.yaml
> 
> diff --git a/Documentation/devicetree/bindings/usb/ti,tusb73x0-pci.yaml b/Documentation/devicetree/bindings/usb/ti,tusb73x0-pci.yaml
> new file mode 100644
> index 000000000000..7083e24d279c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/usb/ti,tusb73x0-pci.yaml
> @@ -0,0 +1,60 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/usb/ti,tusb73x0-pci.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: TUSB73x0 USB 3.0 xHCI Host Controller (PCIe)
> +
> +maintainers:
> +  - Francesco Dolcini <francesco.dolcini@toradex.com>
> +
> +description:
> +  TUSB73x0 USB 3.0 xHCI Host Controller via PCIe x1 Gen2 interface.
> +  The TUSB7320 supports up to two downstream ports, the TUSB7340 supports up
> +  to four downstream ports.

XHCI controller, should be referencing usb-xhci.yaml.

> +
> +properties:
> +  compatible:
> +    const: pci104c,8241

2 parts mentioned above, but only 1 PCI ID?

> +
> +  reg:
> +    maxItems: 1
> +
> +  ti,tusb7320-pwron-active-high:

Drop 'tusb7320-'

> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description:
> +      Configure the polarity of the PWRONx# signals. When this is present, the PWRONx#
> +      pins are active high and their internal pull-down resistors are disabled.
> +      When this is absent, the PWRONx# pins are active low (default) and their internal
> +      pull-down resistors are enabled.
> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    pcie {
> +        #address-cells = <3>;
> +        #size-cells = <2>;
> +
> +        pcie@0 {
> +            device_type = "pci";

You can move this up a level and get rid of this middle node. 

> +            reg = <0x0 0x0 0x0 0x0 0x0>;
> +            bus-range = <0x01 0xff>;

Not needed for examples.

> +
> +            #address-cells = <3>;
> +            #size-cells = <2>;
> +            ranges;
> +
> +            usb@0 {
> +                  compatible = "pci104c,8241";
> +                  reg = <0x10000 0x0 0x0 0x0 0x0>;

In FDT, we generally don't know the bus number because the OS assigns 
them. So it should always be 0 in 'reg'.

Rob