usb: phy: add a new driver for usb part of control module

Added a new driver for the usb part of control module. This has an API
to power on the USB2 phy and an API to write to the mailbox depending on
whether MUSB has to act in host mode or in device mode.

Writing to control module registers for doing the above task which was
previously done in omap glue and in omap-usb2 phy will be removed.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

Documentation/devicetree/bindings/usb/omap-usb.txt

@@ -1,4 +1,4 @@
-OMAP GLUE
+OMAP GLUE AND OTHER OMAP SPECIFIC COMPONENTS
 
 OMAP MUSB GLUE
  - compatible : Should be "ti,omap4-musb" or "ti,omap3-musb"
@@ -16,6 +16,10 @@ OMAP MUSB GLUE
  - power : Should be "50". This signifies the controller can supply upto
    100mA when operating in host mode.
 
+Optional properties:
+ - ctrl-module : phandle of the control module this glue uses to write to
+   mailbox
+
 SOC specific device node entry
 usb_otg_hs: usb_otg_hs@4a0ab000 {
 	compatible = "ti,omap4-musb";
@@ -23,6 +27,7 @@ usb_otg_hs: usb_otg_hs@4a0ab000 {
 	multipoint = <1>;
 	num_eps = <16>;
 	ram_bits = <12>;
+	ctrl-module = <&omap_control_usb>;
 };
 
 Board specific device node entry
@@ -31,3 +36,26 @@ Board specific device node entry
 	mode = <3>;
 	power = <50>;
 };
+
+OMAP CONTROL USB
+
+Required properties:
+ - compatible: Should be "ti,omap-control-usb"
+ - reg : Address and length of the register set for the device. It contains
+   the address of "control_dev_conf" and "otghs_control" or "phy_power_usb"
+   depending upon omap4 or omap5.
+ - reg-names: The names of the register addresses corresponding to the registers
+   filled in "reg".
+ - ti,type: This is used to differentiate whether the control module has
+   usb mailbox or usb3 phy power. omap4 has usb mailbox in control module to
+   notify events to the musb core and omap5 has usb3 phy power register to
+   power on usb3 phy. Should be "1" if it has mailbox and "2" if it has usb3
+   phy power.
+
+omap_control_usb: omap-control-usb@4a002300 {
+	compatible = "ti,omap-control-usb";
+	reg = <0x4a002300 0x4>,
+	      <0x4a00233c 0x4>;
+	reg-names = "control_dev_conf", "otghs_control";
+	ti,type = <1>;
+};

Documentation/devicetree/bindings/usb/usb-phy.txt

@@ -8,10 +8,15 @@ Required properties:
 add the address of control module dev conf register until a driver for
 control module is added
 
+Optional properties:
+ - ctrl-module : phandle of the control module used by PHY driver to power on
+   the PHY.
+
 This is usually a subnode of ocp2scp to which it is connected.
 
 usb2phy@4a0ad080 {
 	compatible = "ti,omap-usb2";
 	reg = <0x4a0ad080 0x58>,
 	      <0x4a002300 0x4>;
+	ctrl-module = <&omap_control_usb>;
 };