usb: mtu3: check capability of usb3 dual role

It is capable of supporting usb3 dual role if there is at least one
usb3 port for device and xhci controller, we can check it from the
controller's capability, so no need the property "mediatek,usb3-drd"
anymore, but I find the property is not decribed in dt-binding.
Meanwhile, also take into account if the u3 port is disabled when the
u3 phy is shared with pcie.
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20220708071903.25752-4-chunfeng.yun@mediatek.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/mtu3/mtu3_plat.c

@@ -190,6 +190,31 @@ static void ssusb_ip_sw_reset(struct ssusb_mtk *ssusb)
 	mtu3_setbits(ssusb->ippc_base, U3D_SSUSB_IP_PW_CTRL2, SSUSB_IP_DEV_PDN);
 }
 
+static void ssusb_u3_drd_check(struct ssusb_mtk *ssusb)
+{
+	struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
+	u32 dev_u3p_num;
+	u32 host_u3p_num;
+	u32 value;
+
+	/* u3 port0 is disabled */
+	if (ssusb->u3p_dis_msk & BIT(0)) {
+		otg_sx->is_u3_drd = false;
+		goto out;
+	}
+
+	value = mtu3_readl(ssusb->ippc_base, U3D_SSUSB_IP_DEV_CAP);
+	dev_u3p_num = SSUSB_IP_DEV_U3_PORT_NUM(value);
+
+	value = mtu3_readl(ssusb->ippc_base, U3D_SSUSB_IP_XHCI_CAP);
+	host_u3p_num = SSUSB_IP_XHCI_U3_PORT_NUM(value);
+
+	otg_sx->is_u3_drd = !!(dev_u3p_num && host_u3p_num);
+
+out:
+	dev_info(ssusb->dev, "usb3-drd: %d\n", otg_sx->is_u3_drd);
+}
+
 static int get_ssusb_rscs(struct platform_device *pdev, struct ssusb_mtk *ssusb)
 {
 	struct device_node *node = pdev->dev.of_node;
@@ -270,7 +295,6 @@ static int get_ssusb_rscs(struct platform_device *pdev, struct ssusb_mtk *ssusb)
 		goto out;
 
 	/* if dual-role mode is supported */
-	otg_sx->is_u3_drd = of_property_read_bool(node, "mediatek,usb3-drd");
 	otg_sx->manual_drd_enabled =
 		of_property_read_bool(node, "enable-manual-drd");
 	otg_sx->role_sw_used = of_property_read_bool(node, "usb-role-switch");
@@ -290,8 +314,7 @@ static int get_ssusb_rscs(struct platform_device *pdev, struct ssusb_mtk *ssusb)
 	}
 
 out:
-	dev_info(dev, "dr_mode: %d, is_u3_dr: %d, drd: %s\n",
-		 ssusb->dr_mode, otg_sx->is_u3_drd,
+	dev_info(dev, "dr_mode: %d, drd: %s\n", ssusb->dr_mode,
 		 otg_sx->manual_drd_enabled ? "manual" : "auto");
 	dev_info(dev, "u2p_dis_msk: %x, u3p_dis_msk: %x\n",
 		 ssusb->u2p_dis_msk, ssusb->u3p_dis_msk);
@@ -353,6 +376,7 @@ static int mtu3_probe(struct platform_device *pdev)
 	}
 
 	ssusb_ip_sw_reset(ssusb);
+	ssusb_u3_drd_check(ssusb);
 
 	if (IS_ENABLED(CONFIG_USB_MTU3_HOST))
 		ssusb->dr_mode = USB_DR_MODE_HOST;