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

Marek Vasut marex at nabladev.com
Sat Oct 17 10:30:37 PDT 2026


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 ?



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