[PATCH 1/2] usb: dwc3: dwc3-generic: check the parent nodes

[Angus Ainslie]

The kernel devicetree has definitions for port and hub nodes as subnodes
to the USB devices. These subnodes don't contain all of the data required
to properly configure the dwc3. Check the parent nodes if the data is not
in the port/hub node.

Here's an example from the librem5 kernel dts file

&usb_dwc3_0 {
	#address-cells = <1>;
	#size-cells = <0>;
	dr_mode = "otg";
	snps,dis_u3_susphy_quirk;
	status = "okay";

	port at 0 {
		reg = <0>;

		typec_hs: endpoint {
			remote-endpoint = <&usb_con_hs>;
		};
	};

	port at 1 {
		reg = <1>;

		typec_ss: endpoint {
			remote-endpoint = <&usb_con_ss>;
		};
	};
};

&usb_dwc3_1 {
	dr_mode = "host";
	status = "okay";
	#address-cells = <1>;
	#size-cells = <0>;

	/* Microchip USB2642 */
	hub at 1 {
		compatible = "usb424,2640";
		reg = <1>;
		#address-cells = <1>;
		#size-cells = <0>;

		mass-storage at 1 {
			compatible = "usb424,4041";
			reg = <1>;
		};
	};
};

Signed-off-by: Angus Ainslie <angus at akkea.ca>
---
 drivers/usb/dwc3/dwc3-generic.c | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-generic.c b/drivers/usb/dwc3/dwc3-generic.c
index 8d53ba7790..01bd0ca190 100644
--- a/drivers/usb/dwc3/dwc3-generic.c
+++ b/drivers/usb/dwc3/dwc3-generic.c
@@ -110,7 +110,12 @@ static int dwc3_generic_of_to_plat(struct udevice *dev)
 	struct dwc3_generic_plat *plat = dev_get_plat(dev);
 	ofnode node = dev_ofnode(dev);
 
-	plat->base = dev_read_addr(dev);
+	if (!strncmp(dev->name, "port", 4) || !strncmp(dev->name, "hub", 3)) {
+		/* This is a leaf so check the parent */
+		plat->base = dev_read_addr(dev->parent);
+	} else {
+		plat->base = dev_read_addr(dev);
+	}
 
 	plat->maximum_speed = usb_get_maximum_speed(node);
 	if (plat->maximum_speed == USB_SPEED_UNKNOWN) {
@@ -120,8 +125,13 @@ static int dwc3_generic_of_to_plat(struct udevice *dev)
 
 	plat->dr_mode = usb_get_dr_mode(node);
 	if (plat->dr_mode == USB_DR_MODE_UNKNOWN) {
-		pr_err("Invalid usb mode setup\n");
-		return -ENODEV;
+		/* might be a leaf so check the parent for mode */
+		node = dev_ofnode(dev->parent);
+		plat->dr_mode = usb_get_dr_mode(node);
+		if (plat->dr_mode == USB_DR_MODE_UNKNOWN) {
+			pr_err("Invalid usb mode setup\n");
+			return -ENODEV;
+		}
 	}
 
 	return 0;
@@ -301,16 +311,20 @@ static int dwc3_glue_bind(struct udevice *parent)
 {
 	ofnode node;
 	int ret;
+	enum usb_dr_mode dr_mode;
+
+	dr_mode = usb_get_dr_mode(dev_ofnode(parent));
 
 	ofnode_for_each_subnode(node, dev_ofnode(parent)) {
 		const char *name = ofnode_get_name(node);
-		enum usb_dr_mode dr_mode;
 		struct udevice *dev;
 		const char *driver = NULL;
 
 		debug("%s: subnode name: %s\n", __func__, name);
 
-		dr_mode = usb_get_dr_mode(node);
+		/* if the parent node doesn't have a mode check the leaf */
+		if (!dr_mode)
+			dr_mode = usb_get_dr_mode(node);
 
 		switch (dr_mode) {
 		case USB_DR_MODE_PERIPHERAL:
@@ -450,6 +464,7 @@ static const struct udevice_id dwc3_glue_ids[] = {
 	{ .compatible = "rockchip,rk3328-dwc3" },
 	{ .compatible = "rockchip,rk3399-dwc3" },
 	{ .compatible = "qcom,dwc3" },
+	{ .compatible = "fsl,imx8mq-dwc3" },
 	{ .compatible = "intel,tangier-dwc3" },
 	{ }
 };
-- 
2.25.1