usb: cdns2: Add main part of Cadence USBHS driver

This patch introduces the main part of Cadence USBHS driver
to Linux kernel.
To reduce the patch size a little bit, the header file gadget.h was
intentionally added as separate patch.

The Cadence USB 2.0 Controller is a highly configurable IP Core which
supports both full and high speed data transfer.

The current driver has been validated with FPGA platform. We have
support for PCIe bus, which is used on FPGA prototyping.
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Message-ID: <20230602102644.77470-3-pawell@cadence.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/udc/Kconfig

@@ -463,6 +463,8 @@ config USB_ASPEED_UDC
 
 source "drivers/usb/gadget/udc/aspeed-vhub/Kconfig"
 
+source "drivers/usb/gadget/udc/cdns2/Kconfig"
+
 #
 # LAST -- dummy/emulated controller
 #

drivers/usb/gadget/udc/Makefile

@@ -42,3 +42,4 @@ obj-$(CONFIG_USB_ASPEED_VHUB)	+= aspeed-vhub/
 obj-$(CONFIG_USB_ASPEED_UDC)	+= aspeed_udc.o
 obj-$(CONFIG_USB_BDC_UDC)	+= bdc/
 obj-$(CONFIG_USB_MAX3420_UDC)	+= max3420_udc.o
+obj-$(CONFIG_USB_CDNS2_UDC)	+= cdns2/

drivers/usb/gadget/udc/cdns2/Kconfig

+config USB_CDNS2_UDC
+	tristate "Cadence USBHS Device Controller"
+	depends on USB_PCI && ACPI && HAS_DMA
+	help
+	  Cadence USBHS Device controller is a PCI based USB peripheral
+	  controller which supports both full and high speed USB 2.0
+	  data transfers.
+
+	  Say "y" to link the driver statically, or "m" to build a
+	  dynamically linked module called "cdns2-udc-pci.ko" and to
+	  force all gadget drivers to also be dynamically linked.

drivers/usb/gadget/udc/cdns2/Makefile

+# SPDX-License-Identifier: GPL-2.0
+# define_trace.h needs to know how to find our header
+
+obj-$(CONFIG_USB_CDNS2_UDC)		+= cdns2-udc-pci.o
+cdns2-udc-pci-$(CONFIG_USB_CDNS2_UDC)	+= cdns2-pci.o cdns2-gadget.o cdns2-ep0.o

drivers/usb/gadget/udc/cdns2/cdns2-pci.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBHS-DEV controller - PCI Glue driver.
+ *
+ * Copyright (C) 2023 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ *
+ */
+
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+
+#include "cdns2-gadget.h"
+
+#define PCI_DRIVER_NAME		"cdns-pci-usbhs"
+#define CDNS_VENDOR_ID		0x17cd
+#define CDNS_DEVICE_ID		0x0120
+#define PCI_BAR_DEV		0
+#define PCI_DEV_FN_DEVICE	0
+
+static int cdns2_pci_probe(struct pci_dev *pdev,
+			   const struct pci_device_id *id)
+{
+	resource_size_t rsrc_start, rsrc_len;
+	struct device *dev = &pdev->dev;
+	struct cdns2_device *priv_dev;
+	struct resource *res;
+	int ret;
+
+	/* For GADGET PCI (devfn) function number is 0. */
+	if (!id || pdev->devfn != PCI_DEV_FN_DEVICE ||
+	    pdev->class != PCI_CLASS_SERIAL_USB_DEVICE)
+		return -EINVAL;
+
+	ret = pcim_enable_device(pdev);
+	if (ret) {
+		dev_err(&pdev->dev, "Enabling PCI device has failed %d\n", ret);
+		return ret;
+	}
+
+	pci_set_master(pdev);
+
+	priv_dev = devm_kzalloc(&pdev->dev, sizeof(*priv_dev), GFP_KERNEL);
+	if (!priv_dev)
+		return -ENOMEM;
+
+	dev_dbg(dev, "Initialize resources\n");
+	rsrc_start = pci_resource_start(pdev, PCI_BAR_DEV);
+	rsrc_len = pci_resource_len(pdev, PCI_BAR_DEV);
+
+	res = devm_request_mem_region(dev, rsrc_start, rsrc_len, "dev");
+	if (!res) {
+		dev_dbg(dev, "controller already in use\n");
+		return -EBUSY;
+	}
+
+	priv_dev->regs = devm_ioremap(dev, rsrc_start, rsrc_len);
+	if (!priv_dev->regs) {
+		dev_dbg(dev, "error mapping memory\n");
+		return -EFAULT;
+	}
+
+	priv_dev->irq = pdev->irq;
+	dev_dbg(dev, "USBSS-DEV physical base addr: %pa\n",
+		&rsrc_start);
+
+	priv_dev->dev = dev;
+
+	priv_dev->eps_supported = 0x000f000f;
+	priv_dev->onchip_tx_buf = 16;
+	priv_dev->onchip_rx_buf = 16;
+
+	ret = cdns2_gadget_init(priv_dev);
+	if (ret)
+		return ret;
+
+	pci_set_drvdata(pdev, priv_dev);
+
+	device_wakeup_enable(&pdev->dev);
+	if (pci_dev_run_wake(pdev))
+		pm_runtime_put_noidle(&pdev->dev);
+
+	return 0;
+}
+
+static void cdns2_pci_remove(struct pci_dev *pdev)
+{
+	struct cdns2_device *priv_dev = pci_get_drvdata(pdev);
+
+	if (pci_dev_run_wake(pdev))
+		pm_runtime_get_noresume(&pdev->dev);
+
+	cdns2_gadget_remove(priv_dev);
+}
+
+static int cdns2_pci_suspend(struct device *dev)
+{
+	struct cdns2_device *priv_dev = dev_get_drvdata(dev);
+
+	return cdns2_gadget_suspend(priv_dev);
+}
+
+static int cdns2_pci_resume(struct device *dev)
+{
+	struct cdns2_device *priv_dev = dev_get_drvdata(dev);
+
+	return cdns2_gadget_resume(priv_dev, 1);
+}
+
+static const struct dev_pm_ops cdns2_pci_pm_ops = {
+	SYSTEM_SLEEP_PM_OPS(cdns2_pci_suspend, cdns2_pci_resume)
+};
+
+static const struct pci_device_id cdns2_pci_ids[] = {
+	{ PCI_VENDOR_ID_CDNS, CDNS_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,
+	  PCI_CLASS_SERIAL_USB_DEVICE, PCI_ANY_ID },
+	{ 0, }
+};
+
+static struct pci_driver cdns2_pci_driver = {
+	.name = "cdns2-pci",
+	.id_table = &cdns2_pci_ids[0],
+	.probe = cdns2_pci_probe,
+	.remove = cdns2_pci_remove,
+	.driver = {
+		.pm = pm_ptr(&cdns2_pci_pm_ops),
+	}
+};
+
+module_pci_driver(cdns2_pci_driver);
+MODULE_DEVICE_TABLE(pci, cdns2_pci_ids);
+
+MODULE_ALIAS("pci:cdns2");
+MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Cadence CDNS2 PCI driver");