[PATCH 2/3] phy: phy-stih407-usb: Add dt documentation for USB picophy found on stih407 SoC family

[Peter Griffin <peter.griffin@linaro.org>]

This patch adds the dt documentation for the usb picophy found on stih407 SoC family
available from STMicroelectronics.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
---
 .../devicetree/bindings/phy/phy-stih407-usb.txt    | 37 ++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/phy-stih407-usb.txt

diff --git a/Documentation/devicetree/bindings/phy/phy-stih407-usb.txt b/Documentation/devicetree/bindings/phy/phy-stih407-usb.txt
new file mode 100644
index 0000000..650d346
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/phy-stih407-usb.txt
@@ -0,0 +1,37 @@
+ST STiH407 USB-PHY controller
+
+This file documents the dt bindings for the picoPHY driver which is the PHY for both USB2 and USB3 host controllers
+controllers available on STiH407 SoC families.
+
+On STiH410, we have to use the DWC3 port#2 with a picoPHY to manage USB2
+devices. The USB2 Controller will use the ports #0 and #1.
+
+This is to document the DT parameters to be passed from the blob in that case.
+
+Required properties:
+- compatible		: should be "st,stih407-usb2-phy"
+- reg			: contain the offset and length of the system configuration registers
+			  used as glue logic to control & parameter phy
+- reg-names		: the names of the system configuration registers in "reg", should be "param" and "reg"
+- st,syscfg		: sysconfig register to manage phy parameter at driver level
+- resets		: list of phandle and reset specifier pairs. There should be two entries, one
+			  for the whole phy and one for the port
+- reset-names		: list of reset signal names. Should be "global" and "port"
+See: Documentation/devicetree/bindings/reset/st,sti-powerdown.txt
+See: Documentation/devicetree/bindings/reset/reset.txt
+
+Example:
+
+usb2_picophy0: usbpicophy@0 {
+	compatible	= "st,stih407-usb2-phy";
+	reg		= <0xf8 0x04>,	/* syscfg 5062 */
+			  <0xf4 0x04>;	/* syscfg 5061 */
+	reg-names	= "param",
+			  "ctrl";
+			  #phy-cells = <0>;
+	st,syscfg	= <&syscfg_core>;
+	resets		= <&softreset STIH407_PICOPHY_SOFTRESET>,
+			  <&picophyreset STIH407_PICOPHY0_RESET>;
+	reset-names	= "global",
+			  "port";
+};
-- 
1.9.1