Re: [PATCH devicetree v3] dt-bindings: phy: Add `tx-p2p-microvolt` property binding

On Fri, 4 Feb 2022 20:18:40 -0600
Rob Herring [off-list ref] wrote:

On Fri, Jan 21, 2022 at 11:18:09AM -0800, Florian Fainelli wrote:

quoted

On 1/19/22 5:11 AM, Marek Behún wrote:  

quoted

Common PHYs and network PCSes often have the possibility to specify
peak-to-peak voltage on the differential pair - the default voltage
sometimes needs to be changed for a particular board.

Add properties `tx-p2p-microvolt` and `tx-p2p-microvolt-names` for this
purpose. The second property is needed to specify the mode for the
corresponding voltage in the `tx-p2p-microvolt` property, if the voltage
is to be used only for speficic mode. More voltage-mode pairs can be
specified.

Example usage with only one voltage (it will be used for all supported
PHY modes, the `tx-p2p-microvolt-names` property is not needed in this
case):

  tx-p2p-microvolt = <915000>;

Example usage with voltages for multiple modes:

  tx-p2p-microvolt = <915000>, <1100000>, <1200000>;
  tx-p2p-microvolt-names = "2500base-x", "usb", "pcie";

Add these properties into a separate file phy/transmit-amplitude.yaml,
which should be referenced by any binding that uses it.  

p2p commonly means peer to peer which incidentally could be confusing,
can you spell out the property entire:

tx-peaktopeak-microvolt or:

tx-pk2pk-microvolt for a more compact name maybe?  

Peer to peer makes little sense in terms of a voltage. I think this is 
fine as-is.

Cool. Should this get merged via devicetree, or via phy maintainers?
Or should I resend this together with patches that make use of this
property? (In that case can you add your Ack?)

Thanks.

Marek