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+Device tree structures used by register based MDIO muxes is described here.
+This binding is based on reg-mux.txt binding in Linux and is currently used by
+mdio-mux-i2creg driver in U-Boot.
+
+Required properties:
+#mux-control-cells = <1> indicates how many registers are used for mux
+ selection. mux-reg-mask property described below must
+ include this number of pairs.
+mux-reg-masks = <reg mask> describes pairs of register offset and register mask.
+ Register bits enabled in mask are set to the selection
+ value defined in reg property of child MDIOs to control
+ selection.
+Properties described in mdio-mux.txt also apply.
+
+Example structure, used on Freescale LS1028A QDS board:
+
+&i2c0 {
+ status = "okay";
+ u-boot,dm-pre-reloc;
+
+ fpga@66 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "simple-mfd";
+ reg = <0x66>;
+
+ mux-mdio@54 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "mdio-mux-i2creg";
+ reg = <0x54>;
+ #mux-control-cells = <1>;
+ mux-reg-masks = <0x54 0xf0>;
+ mdio-parent-bus = <&mdio0>;
+
+ /* on-board MDIO with a single RGMII PHY */
+ mdio@00 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x00>;
+
+ /* on-board 1G RGMII PHY */
+ qds_phy0: phy@5 {
+ reg = <5>;
+ };
+ };
+ /* card slot 1 */
+ mdio@40 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x40>;
+ /* VSC8234 1G SGMII card */
+ sgmii_port0: phy@1c {
+ reg = <0x1c>;
+ };
+ };
+ /* card slot 2 */
+ mdio@50 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x50>;
+ };
+ /* card slot 3 */
+ mdio@60 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x60>;
+ };
+ /* card slot 4 */
+ mdio@70 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ reg = <0x70>;
+ };
+ };
+ };
+};
+
+/* Parent MDIO, defined in SoC .dtsi file, just enabled here */
+&mdio0 {
+ status = "okay";
+};
This binding documents two properties that describe the registers used to perform MUX selection. Signed-off-by: Alex Marginean <alexm.osslist@gmail.com> --- Changes in v2: - renamed APIs, config options to mdio_mux_i2creg (instead of i2c_reg) - expanded example to include all QDS card slots doc/device-tree-bindings/net/mdio-mux-reg.txt | 82 +++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 doc/device-tree-bindings/net/mdio-mux-reg.txt