linux-arkmicro/linux/Documentation/devicetree/bindings/net/sff,sfp.txt

Small Form Factor (SFF) Committee Small Form-factor Pluggable (SFP)
Transceiver

Required properties:

- compatible : must be one of
  "sff,sfp" for SFP modules
  "sff,sff" for soldered down SFF modules

- i2c-bus : phandle of an I2C bus controller for the SFP two wire serial
  interface

Optional Properties:

- mod-def0-gpios : GPIO phandle and a specifier of the MOD-DEF0 (AKA Mod_ABS)
  module presence input gpio signal, active (module absent) high. Must
  not be present for SFF modules

- los-gpios : GPIO phandle and a specifier of the Receiver Loss of Signal
  Indication input gpio signal, active (signal lost) high

- tx-fault-gpios : GPIO phandle and a specifier of the Module Transmitter
  Fault input gpio signal, active (fault condition) high

- tx-disable-gpios : GPIO phandle and a specifier of the Transmitter Disable
  output gpio signal, active (Tx disable) high

- rate-select0-gpios : GPIO phandle and a specifier of the Rx Signaling Rate
  Select (AKA RS0) output gpio signal, low: low Rx rate, high: high Rx rate
  Must not be present for SFF modules

- rate-select1-gpios : GPIO phandle and a specifier of the Tx Signaling Rate
  Select (AKA RS1) output gpio signal (SFP+ only), low: low Tx rate, high:
  high Tx rate. Must not be present for SFF modules

- maximum-power-milliwatt : Maximum module power consumption
  Specifies the maximum power consumption allowable by a module in the
  slot, in milli-Watts.  Presently, modules can be up to 1W, 1.5W or 2W.

Example #1: Direct serdes to SFP connection

sfp_eth3: sfp-eth3 {
	compatible = "sff,sfp";
	i2c-bus = <&sfp_1g_i2c>;
	los-gpios = <&cpm_gpio2 22 GPIO_ACTIVE_HIGH>;
	mod-def0-gpios = <&cpm_gpio2 21 GPIO_ACTIVE_LOW>;
	maximum-power-milliwatt = <1000>;
	pinctrl-names = "default";
	pinctrl-0 = <&cpm_sfp_1g_pins &cps_sfp_1g_pins>;
	tx-disable-gpios = <&cps_gpio1 24 GPIO_ACTIVE_HIGH>;
	tx-fault-gpios = <&cpm_gpio2 19 GPIO_ACTIVE_HIGH>;
};

&cps_emac3 {
	phy-names = "comphy";
	phys = <&cps_comphy5 0>;
	sfp = <&sfp_eth3>;
};

Example #2: Serdes to PHY to SFP connection

sfp_eth0: sfp-eth0 {
	compatible = "sff,sfp";
	i2c-bus = <&sfpp0_i2c>;
	los-gpios = <&cps_gpio1 28 GPIO_ACTIVE_HIGH>;
	mod-def0-gpios = <&cps_gpio1 27 GPIO_ACTIVE_LOW>;
	pinctrl-names = "default";
	pinctrl-0 = <&cps_sfpp0_pins>;
	tx-disable-gpios = <&cps_gpio1 29 GPIO_ACTIVE_HIGH>;
	tx-fault-gpios  = <&cps_gpio1 26 GPIO_ACTIVE_HIGH>;
};

p0_phy: ethernet-phy@0 {
	compatible = "ethernet-phy-ieee802.3-c45";
	pinctrl-names = "default";
	pinctrl-0 = <&cpm_phy0_pins &cps_phy0_pins>;
	reg = <0>;
	interrupt = <&cpm_gpio2 18 IRQ_TYPE_EDGE_FALLING>;
	sfp = <&sfp_eth0>;
};

&cpm_eth0 {
	phy = <&p0_phy>;
	phy-mode = "10gbase-kr";
};