usb: dwc3: Add generic DWC3 glue logic driver

By enabling BLK by default this is the next driver which needs to get
support for DM_USB. Adding generic DWC3 glue logic which only
parse nodes and read device mode. Based on it probe proper
host/peripheral DWC3 drivers for it.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index ae7fc1c..943b763 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -37,6 +37,12 @@
 
 	  Say 'Y' here if you have one such device
 
+config USB_DWC3_GENERIC
+	bool "Xilinx ZynqMP and similar Platforms"
+	depends on DM_USB && USB_DWC3
+	help
+	  Some platforms can reuse this DWC3 generic implementation.
+
 config USB_DWC3_UNIPHIER
 	bool "DesignWare USB3 Host Support on UniPhier Platforms"
 	depends on ARCH_UNIPHIER && USB_XHCI_DWC3
diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
index cd18b8d9e..60b5515 100644
--- a/drivers/usb/dwc3/Makefile
+++ b/drivers/usb/dwc3/Makefile
@@ -7,6 +7,7 @@
 obj-$(CONFIG_USB_DWC3_GADGET)		+= gadget.o ep0.o
 
 obj-$(CONFIG_USB_DWC3_OMAP)		+= dwc3-omap.o
+obj-$(CONFIG_USB_DWC3_GENERIC)		+= dwc3-generic.o
 obj-$(CONFIG_USB_DWC3_UNIPHIER)		+= dwc3-uniphier.o
 obj-$(CONFIG_USB_DWC3_PHY_OMAP)		+= ti_usb_phy.o
 obj-$(CONFIG_USB_DWC3_PHY_SAMSUNG)	+= samsung_usb_phy.o
diff --git a/drivers/usb/dwc3/dwc3-generic.c b/drivers/usb/dwc3/dwc3-generic.c
new file mode 100644
index 0000000..ca63eac
--- /dev/null
+++ b/drivers/usb/dwc3/dwc3-generic.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier:     GPL-2.0
+/*
+ * Generic DWC3 Glue layer
+ *
+ * Copyright (C) 2016 - 2018 Xilinx, Inc.
+ *
+ * Based on dwc3-omap.c.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/device-internal.h>
+#include <dm/lists.h>
+#include <linux/usb/otg.h>
+#include <linux/compat.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+#include <malloc.h>
+#include <usb.h>
+#include "core.h"
+#include "gadget.h"
+#include "linux-compat.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int usb_gadget_handle_interrupts(int index)
+{
+	struct dwc3 *priv;
+	struct udevice *dev;
+	int ret;
+
+	ret = uclass_first_device(UCLASS_USB_DEV_GENERIC, &dev);
+	if (!dev || ret) {
+		pr_err("No USB device found\n");
+		return -ENODEV;
+	}
+
+	priv = dev_get_priv(dev);
+
+	dwc3_gadget_uboot_handle_interrupt(priv);
+
+	return 0;
+}
+
+static int dwc3_generic_peripheral_probe(struct udevice *dev)
+{
+	struct dwc3 *priv = dev_get_priv(dev);
+
+	return dwc3_init(priv);
+}
+
+static int dwc3_generic_peripheral_remove(struct udevice *dev)
+{
+	struct dwc3 *priv = dev_get_priv(dev);
+
+	dwc3_remove(priv);
+
+	return 0;
+}
+
+static int dwc3_generic_peripheral_ofdata_to_platdata(struct udevice *dev)
+{
+	struct dwc3 *priv = dev_get_priv(dev);
+	int node = dev_of_offset(dev);
+
+	priv->regs = (void *)devfdt_get_addr(dev);
+	priv->regs += DWC3_GLOBALS_REGS_START;
+
+	priv->maximum_speed = usb_get_maximum_speed(node);
+	if (priv->maximum_speed == USB_SPEED_UNKNOWN) {
+		pr_err("Invalid usb maximum speed\n");
+		return -ENODEV;
+	}
+
+	priv->dr_mode = usb_get_dr_mode(node);
+	if (priv->dr_mode == USB_DR_MODE_UNKNOWN) {
+		pr_err("Invalid usb mode setup\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int dwc3_generic_peripheral_bind(struct udevice *dev)
+{
+	return device_probe(dev);
+}
+
+U_BOOT_DRIVER(dwc3_generic_peripheral) = {
+	.name	= "dwc3-generic-peripheral",
+	.id	= UCLASS_USB_DEV_GENERIC,
+	.ofdata_to_platdata = dwc3_generic_peripheral_ofdata_to_platdata,
+	.probe = dwc3_generic_peripheral_probe,
+	.remove = dwc3_generic_peripheral_remove,
+	.bind = dwc3_generic_peripheral_bind,
+	.platdata_auto_alloc_size = sizeof(struct usb_platdata),
+	.priv_auto_alloc_size = sizeof(struct dwc3),
+	.flags	= DM_FLAG_ALLOC_PRIV_DMA,
+};
+
+static int dwc3_generic_bind(struct udevice *parent)
+{
+	const void *fdt = gd->fdt_blob;
+	int node;
+	int ret;
+
+	for (node = fdt_first_subnode(fdt, dev_of_offset(parent)); node > 0;
+	     node = fdt_next_subnode(fdt, node)) {
+		const char *name = fdt_get_name(fdt, node, NULL);
+		enum usb_dr_mode dr_mode;
+		struct udevice *dev;
+		const char *driver;
+
+		debug("%s: subnode name: %s\n", __func__, name);
+		if (strncmp(name, "dwc3@", 4))
+			continue;
+
+		dr_mode = usb_get_dr_mode(node);
+
+		switch (dr_mode) {
+		case USB_DR_MODE_PERIPHERAL:
+		case USB_DR_MODE_OTG:
+			debug("%s: dr_mode: OTG or Peripheral\n", __func__);
+			driver = "dwc3-generic-peripheral";
+			break;
+		case USB_DR_MODE_HOST:
+			debug("%s: dr_mode: HOST\n", __func__);
+			driver = "dwc3-generic-host";
+			break;
+		default:
+			debug("%s: unsupported dr_mode\n", __func__);
+			return -ENODEV;
+		};
+
+		ret = device_bind_driver_to_node(parent, driver, name,
+						 offset_to_ofnode(node), &dev);
+		if (ret) {
+			debug("%s: not able to bind usb device mode\n",
+			      __func__);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct udevice_id dwc3_generic_ids[] = {
+	{ .compatible = "xlnx,zynqmp-dwc3" },
+	{ }
+};
+
+U_BOOT_DRIVER(dwc3_generic_wrapper) = {
+	.name	= "dwc3-generic-wrapper",
+	.id	= UCLASS_MISC,
+	.of_match = dwc3_generic_ids,
+	.bind = dwc3_generic_bind,
+};