Re: [PATCH 3/6] arm64: dts: qcom: ipq5332: Add MDIO device tree

From: Dmitry Baryshkov
Date: Thu Jan 11 2024 - 11:13:32 EST


On Thu, 11 Jan 2024 at 18:00, Jie Luo <quic_luoj@xxxxxxxxxxx> wrote:
>
>
>
> On 1/10/2024 9:35 PM, Andrew Lunn wrote:
> > On Wed, Jan 10, 2024 at 07:20:56PM +0800, Luo Jie wrote:
> >> Add the MDIO device tree of ipq5332.
> >>
> >> Signed-off-by: Luo Jie <quic_luoj@xxxxxxxxxxx>
> >> ---
> >> arch/arm64/boot/dts/qcom/ipq5332.dtsi | 44 +++++++++++++++++++++++++++
> >> 1 file changed, 44 insertions(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/qcom/ipq5332.dtsi b/arch/arm64/boot/dts/qcom/ipq5332.dtsi
> >> index bc89480820cb..e6c780e69d6e 100644
> >> --- a/arch/arm64/boot/dts/qcom/ipq5332.dtsi
> >> +++ b/arch/arm64/boot/dts/qcom/ipq5332.dtsi
> >> @@ -214,6 +214,38 @@ serial_0_pins: serial0-state {
> >> drive-strength = <8>;
> >> bias-pull-up;
> >> };
> >> +
> >> + mdio0_pins: mdio0-state {
> >> + mux_0 {
> >> + pins = "gpio25";
> >> + function = "mdc0";
> >> + drive-strength = <8>;
> >> + bias-disable;
> >> + };
> >> +
> >> + mux_1 {
> >> + pins = "gpio26";
> >> + function = "mdio0";
> >> + drive-strength = <8>;
> >> + bias-pull-up;
> >> + };
> >> + };
> >> +
> >> + mdio1_pins: mdio1-state {
> >> + mux_0 {
> >> + pins = "gpio27";
> >> + function = "mdc1";
> >> + drive-strength = <8>;
> >> + bias-disable;
> >> + };
> >> +
> >> + mux_1 {
> >> + pins = "gpio28";
> >> + function = "mdio1";
> >> + drive-strength = <8>;
> >> + bias-pull-up;
> >> + };
> >
> > I don't know why i'm asking this, because i don't really expect a
> > usable answer. What sort of MUX is this? Should you be using one of
> > the muxes in drivers/net/mdio/mdio-mux-* or something similar?
> >
> > Andrew
>
> Sorry for the confusion, the pin nodes are for the MDIO and MDC, these
> PINs are used by the dedicated hardware MDIO block in the SoC. I will
> update the node name from mux_0 to MDC, mux_1 to MDIO, to make it clear.
> The driver for this node is drivers/net/mdio/mdio-ipq4019.c, it is not
> related to the mdio-mux-* code.

Have you read Documentation/devicetree/bindings/pinctrl/qcom,ipq5332-tlmm.yaml
? Have you validated your DTSI files against DT schema? How many
warnings will you observe if you rename the mux_0 node to MDC?

--
With best wishes
Dmitry