Re: [net-next,PATCH 2/2] enetc: Make eMDIO MDC rate configurable from DT

From: Marek Vasut

Date: Sat Oct 17 2026 - 14:33:04 EST


On 10/17/26 4:24 AM, Wei Fang wrote:

[...]

+int enetc_mdio_update_mdc_div(struct mii_bus *bus)
+{
+ struct enetc_mdio_priv *mdio_priv = bus->priv;
+ struct device *dev = bus->parent;
+ struct clk *enet_clk;
+ u32 div, mdc_freq;
+
+ if (device_property_read_u32(dev, "clock-frequency", &mdc_freq))
+ return 0;
+
+ enet_clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(enet_clk))
+ return dev_err_probe(dev, PTR_ERR(enet_clk),
+ "Input clock unknown, not changing MDC
frequency\n");

binding said clock is optional. If return failure here, it will block
existing dts, which have not clock property.


For EMDIO device, the clocks property is not added to
fsl,enetc-mdio.yaml, I suppose this property should be added to the
dt-binding doc if the clock is really needed here.

Isn't this what 1/2 in this series does ? (maybe I misunderstood this paragraph)

For ENETC device, we already have a 'ref' clock in the enetc node,
so devm_clk_get(dev, NULL) may get the 'ref' clock rather than the
system clock of NETC.
Shouldn't the clock be described in the MDIO DT node ?