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+* Microsemi - vsc8531 Giga bit ethernet phy
+
+Optional properties:
+- vsc8531,vddmac : The vddmac in mV. Allowed values is listed
+ in the first row of Table 1 (below).
+ This property is only used in combination
+ with the 'edge-slowdown' property.
+ Default value is 3300.
+- vsc8531,edge-slowdown : % the edge should be slowed down relative to
+ the fastest possible edge time.
+ Edge rate sets the drive strength of the MAC
+ interface output signals. Changing the
+ drive strength will affect the edge rate of
+ the output signal. The goal of this setting
+ is to help reduce electrical emission (EMI)
+ by being able to reprogram drive strength
+ and in effect slow down the edge rate if
+ desired.
+ To adjust the edge-slowdown, the 'vddmac'
+ must be specified. Table 1 lists the
+ supported edge-slowdown values for a given
+ 'vddmac'.
+ Default value is 0%.
+ Ref: Table:1 - Edge rate change (below).
+- vsc8531,led-[N]-mode : LED mode. Specify how the LED[N] should behave.
+ N depends on the number of LEDs supported by a
+ PHY.
+ Allowed values are defined in
+ "include/dt-bindings/net/mscc-phy-vsc8531.h".
+ Default values are VSC8531_LINK_1000_ACTIVITY (1),
+ VSC8531_LINK_100_ACTIVITY (2),
+ VSC8531_LINK_ACTIVITY (0) and
+ VSC8531_DUPLEX_COLLISION (8).
+- load-save-gpios : GPIO used for the load/save operation of the PTP
+ hardware clock (PHC).
+
+
+Table: 1 - Edge rate change
+----------------------------------------------------------------|
+| Edge Rate Change (VDDMAC) |
+| |
+| 3300 mV 2500 mV 1800 mV 1500 mV |
+|---------------------------------------------------------------|
+| 0% 0% 0% 0% |
+| (Fastest) (recommended) (recommended) |
+|---------------------------------------------------------------|
+| 2% 3% 5% 6% |
+|---------------------------------------------------------------|
+| 4% 6% 9% 14% |
+|---------------------------------------------------------------|
+| 7% 10% 16% 21% |
+|(recommended) (recommended) |
+|---------------------------------------------------------------|
+| 10% 14% 23% 29% |
+|---------------------------------------------------------------|
+| 17% 23% 35% 42% |
+|---------------------------------------------------------------|
+| 29% 37% 52% 58% |
+|---------------------------------------------------------------|
+| 53% 63% 76% 77% |
+| (slowest) |
+|---------------------------------------------------------------|
+
+Example:
+
+ vsc8531_0: ethernet-phy@0 {
+ compatible = "ethernet-phy-id0007.0570";
+ vsc8531,vddmac = <3300>;
+ vsc8531,edge-slowdown = <7>;
+ vsc8531,led-0-mode = <VSC8531_LINK_1000_ACTIVITY>;
+ vsc8531,led-1-mode = <VSC8531_LINK_100_ACTIVITY>;
+ load-save-gpios = <&gpio 10 GPIO_ACTIVE_HIGH>;
+ };