Re: [PATCH RFC 1/7] dt: bindings: add qcom,qps615.yaml

From: Rob Herring
Date: Thu Jun 27 2024 - 11:31:36 EST


On Wed, Jun 26, 2024 at 06:07:49PM +0530, Krishna chaitanya chundru wrote:
> qps615 is a driver for Qualcomm PCIe switch driver which controls
> power & configuration of the hardware.
> Add a bindings document for the driver.
>
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx>
> ---
> .../devicetree/bindings/pci/qcom,qps615.yaml | 73 ++++++++++++++++++++++
> 1 file changed, 73 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pci/qcom,qps615.yaml b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> new file mode 100644
> index 000000000000..f090683f9e2f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pci/qcom,qps615.yaml
> @@ -0,0 +1,73 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pci/qcom,pcie-qps615.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm QPS615 PCIe switch
> +
> +maintainers:
> + - Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx>
> +
> +description: |
> + Qualcomm QPS615 PCIe switch has one upstream and three downstream
> + ports. One of the downstream ports is used as endpoint device of
> + Ethernet MAC. Other two downstream ports are supposed to connect
> + to external device.
> +
> + The power controlled by the GPIO's, if we enable the GPIO's the
> + power to the switch will be on.
> +
> + The QPS615 PCIe switch is configured through I2C interface before
> + PCIe link is established.
> +

As a PCI device and implementing a PCI bus, you need to reference
pci-pci-bridge.yaml. And you'll need to fix your example when you add
that.

> +properties:
> + compatible:
> + enum:
> + - pci1179,0623
> +
> + reg:
> + maxItems: 1
> +
> + vdd-supply:
> + description: |
> + Phandle to the vdd input voltage which are fixed regulators which
> + in are mapped to the GPIO's.
> +
> + switch-i2c-cntrl:
> + description: |
> + phandle to i2c controller which is used to configure the PCIe
> + switch.

There's a somewhat standard property for this purpose: i2c-bus

> +
> +required:
> + - compatible
> + - reg
> + - vdd-supply
> + - switch-i2c-cntrl
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + pcie {
> + #address-cells = <3>;
> + #size-cells = <2>;
> +
> + pcie@0 {
> + device_type = "pci";
> + reg = <0x0 0x0 0x0 0x0 0x0>;
> + #address-cells = <3>;
> + #size-cells = <2>;
> + ranges;
> +
> + bus-range = <0x01 0xff>;

Unless there's a h/w limitation, you don't need this.

> +
> + qps615@0 {
> + compatible = "pci1179,0623";
> + reg = <0x10000 0x0 0x0 0x0 0x0>;
> +
> + vdd-supply = <&vdd>;
> + switch-i2c-cntrl = <&foo>;
> + };
> + };
> + };
>
> --
> 2.42.0
>