usb: dwc3: Add dwc3 glue driver support for STi

This patch adds the ST glue logic to manage the DWC3 HC
on STiH407 SoC family. It configures the internal glue
logic and syscfg registers.

Part of this code been extracted from kernel.org driver
(drivers/usb/dwc3/dwc3-st.c)

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/doc/device-tree-bindings/usb/dwc3-st.txt b/doc/device-tree-bindings/usb/dwc3-st.txt
new file mode 100644
index 0000000000..a26a1397ed
--- /dev/null
+++ b/doc/device-tree-bindings/usb/dwc3-st.txt
@@ -0,0 +1,60 @@
+ST DWC3 glue logic
+
+This file documents the parameters for the dwc3-st driver.
+This driver controls the glue logic used to configure the dwc3 core on
+STiH407 based platforms.
+
+Required properties:
+ - compatible	: must be "st,stih407-dwc3"
+ - reg		: glue logic base address and USB syscfg ctrl register offset
+ - reg-names	: should be "reg-glue" and "syscfg-reg"
+ - st,syscon	: should be phandle to system configuration node which
+		  encompasses the glue registers
+ - resets	: list of phandle and reset specifier pairs. There should be two entries, one
+		  for the powerdown and softreset lines of the usb3 IP
+ - reset-names	: list of reset signal names. Names should be "powerdown" and "softreset"
+
+ - #address-cells, #size-cells : should be '1' if the device has sub-nodes
+   with 'reg' property
+
+ - pinctl-names	: A pinctrl state named "default" must be defined
+
+ - pinctrl-0	: Pin control group
+
+ - ranges	: allows valid 1:1 translation between child's address space and
+		  parent's address space
+
+Sub-nodes:
+The dwc3 core should be added as subnode to ST DWC3 glue as shown in the
+example below.
+
+NB: The dr_mode property is NOT optional for this driver, as the default value
+is "otg", which isn't supported by this SoC. Valid dr_mode values for dwc3-st are
+either "host" or "device".
+
+Example:
+
+st_dwc3: dwc3@8f94000 {
+	status		= "disabled";
+	compatible	= "st,stih407-dwc3";
+	reg		= <0x08f94000 0x1000>, <0x110 0x4>;
+	reg-names	= "reg-glue", "syscfg-reg";
+	st,syscfg	= <&syscfg_core>;
+	resets		= <&powerdown STIH407_USB3_POWERDOWN>,
+			  <&softreset STIH407_MIPHY2_SOFTRESET>;
+	reset-names	= "powerdown", "softreset";
+	#address-cells	= <1>;
+	#size-cells	= <1>;
+	pinctrl-names	= "default";
+	pinctrl-0	= <&pinctrl_usb3>;
+	ranges;
+
+	dwc3: dwc3@9900000 {
+		compatible	= "snps,dwc3";
+		reg		= <0x09900000 0x100000>;
+		interrupts	= <GIC_SPI 155 IRQ_TYPE_NONE>;
+		dr_mode		= "host";
+		phy-names	= "usb2-phy", "usb3-phy";
+		phys		= <&usb2_picophy2>, <&phy_port2 PHY_TYPE_USB3>;
+	};
+};