[PATCH RFC 2/5] usb:cdns3: Add pci to platform driver wrapper

[Pawel Laszczak <pawell@cadence.com>]

Patch adds PCI specific glue driver that creates and registers in-system
cdns-usbssp platform device. Thanks to that we will be able to use
the cdns-usbssp platform driver for USBSS-DEV controller
build on PCI board.

Signed-off-by: Pawel Laszczak <pawell@cadence.com>
---
 drivers/usb/Kconfig           |   1 +
 drivers/usb/Makefile          |   1 +
 drivers/usb/cdnsp/Kconfig     |  26 +++++
 drivers/usb/cdnsp/Makefile    |   3 +
 drivers/usb/cdnsp/cdnsp-pci.c | 214 ++++++++++++++++++++++++++++++++++
 5 files changed, 245 insertions(+)
 create mode 100644 drivers/usb/cdnsp/Kconfig
 create mode 100644 drivers/usb/cdnsp/Makefile
 create mode 100644 drivers/usb/cdnsp/cdnsp-pci.c

diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index 26475b409b53..555c4a4cb465 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -112,6 +112,7 @@ source "drivers/usb/usbip/Kconfig"
 endif
 
 source "drivers/usb/cdns3/Kconfig"
+source "drivers/usb/cdnsp/Kconfig"
 
 source "drivers/usb/mtu3/Kconfig"
 
diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
index 1c1c1d659394..84727f7a4b92 100644
--- a/drivers/usb/Makefile
+++ b/drivers/usb/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_USB_DWC2)		+= dwc2/
 obj-$(CONFIG_USB_ISP1760)	+= isp1760/
 
 obj-$(CONFIG_USB_CDNS3)		+= cdns3/
+obj-$(CONFIG_USB_CDNSP)		+= cdnsp/
 
 obj-$(CONFIG_USB_MON)		+= mon/
 obj-$(CONFIG_USB_MTU3)		+= mtu3/
diff --git a/drivers/usb/cdnsp/Kconfig b/drivers/usb/cdnsp/Kconfig
new file mode 100644
index 000000000000..5796a19bb8a0
--- /dev/null
+++ b/drivers/usb/cdnsp/Kconfig
@@ -0,0 +1,26 @@
+config USB_CDNSP
+	tristate "Cadence CDNSP Dual-Role Controller"
+	depends on USB_SUPPORT && (USB || USB_GADGET) && HAS_DMA
+	select USB_XHCI_PLATFORM if USB_XHCI_HCD
+	select USB_ROLE_SWITCH
+	help
+	  Say Y here if your system has a Cadence CDNSP dual-role controller.
+	  It supports: dual-role switch Host-only, and Peripheral-only.
+
+	  If you choose to build this driver is a dynamically linked
+	  module, the module will be called cdnsp.ko.
+
+if USB_CDNSP
+
+config USB_CDNSP_PCI
+	tristate "Cadence CDNSP support on PCIe-based platforms"
+	depends on USB_PCI && ACPI
+	default USB_CDNSP
+	help
+	  If you're using the CDNSP Core IP with a PCIe, please say
+	  'Y' or 'M' here.
+
+	  If you choose to build this driver as module it will
+	  be dynamically linked and module will be called cdnsp-pci.ko
+
+endif
diff --git a/drivers/usb/cdnsp/Makefile b/drivers/usb/cdnsp/Makefile
new file mode 100644
index 000000000000..21adf3eb2f7d
--- /dev/null
+++ b/drivers/usb/cdnsp/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_USB_CDNSP_PCI)		+= cdnsp-pci.o
diff --git a/drivers/usb/cdnsp/cdnsp-pci.c b/drivers/usb/cdnsp/cdnsp-pci.c
new file mode 100644
index 000000000000..7e05d584d57c
--- /dev/null
+++ b/drivers/usb/cdnsp/cdnsp-pci.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence PCI Glue driver.
+ *
+ * Copyright (C) 2019 Cadence.
+ *
+ * Author: Pawel Laszczak <pawell@cadence.com>
+ *
+ */
+
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+
+struct cdnsp_wrap {
+	struct platform_device *plat_dev;
+	struct resource dev_res[6];
+	int devfn;
+};
+
+#define RES_IRQ_HOST_ID		0
+#define RES_IRQ_PERIPHERAL_ID	1
+#define RES_IRQ_OTG_ID		2
+#define RES_HOST_ID		3
+#define RES_DEV_ID		4
+#define RES_DRD_ID		5
+
+#define PCI_BAR_HOST		0
+#define PCI_BAR_OTG		0
+#define PCI_BAR_DEV		2
+
+#define PCI_DEV_FN_HOST_DEVICE	0
+#define PCI_DEV_FN_OTG		1
+
+#define PCI_DRIVER_NAME		"cdns-pci-usbssp"
+#define PLAT_DRIVER_NAME	"cdns-usbssp"
+
+#define CDNS_VENDOR_ID		0x17cd
+#define CDNS_DEVICE_ID		0x0100
+#define CDNS_DRD_IF		(PCI_CLASS_SERIAL_USB << 8 | 0x80)
+
+static struct pci_dev *cdnsp_get_second_fun(struct pci_dev *pdev)
+{
+	struct pci_dev *func;
+
+	/*
+	 * Gets the second function.
+	 * It's little tricky, but this platform has two function.
+	 * The fist keeps resources for Host/Device while the second
+	 * keeps resources for DRD/OTG.
+	 */
+	func = pci_get_device(pdev->vendor, pdev->device, NULL);
+	if (unlikely(!func))
+		return NULL;
+
+	if (func->devfn == pdev->devfn) {
+		func = pci_get_device(pdev->vendor, pdev->device, func);
+		if (unlikely(!func))
+			return NULL;
+	}
+
+	return func;
+}
+
+static int cdnsp_pci_probe(struct pci_dev *pdev,
+			   const struct pci_device_id *id)
+{
+	struct platform_device_info plat_info;
+	struct cdnsp_wrap *wrap;
+	struct resource *res;
+	struct pci_dev *func;
+	int err;
+
+	/*
+	 * For GADGET/HOST PCI (devfn) function number is 0,
+	 * for OTG PCI (devfn) function number is 1.
+	 */
+	if (!id || (pdev->devfn != PCI_DEV_FN_HOST_DEVICE &&
+		    pdev->devfn != PCI_DEV_FN_OTG))
+		return -EINVAL;
+
+	func = cdnsp_get_second_fun(pdev);
+	if (unlikely(!func))
+		return -EINVAL;
+
+	if (func->class == PCI_CLASS_SERIAL_USB_XHCI ||
+	    pdev->class == PCI_CLASS_SERIAL_USB_XHCI)
+		return -EINVAL;
+
+	err = pcim_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "Enabling PCI device has failed %d\n", err);
+		return err;
+	}
+
+	pci_set_master(pdev);
+
+	if (pci_is_enabled(func)) {
+		wrap = pci_get_drvdata(func);
+	} else {
+		wrap = kzalloc(sizeof(*wrap), GFP_KERNEL);
+		if (!wrap) {
+			pci_disable_device(pdev);
+			return -ENOMEM;
+		}
+	}
+
+	res = wrap->dev_res;
+
+	/* For GADGET device function number is 0. */
+	if (pdev->devfn == 0) {
+		/* Function 0: host(BAR_0) + device(BAR_1).*/
+		dev_dbg(&pdev->dev, "Initialize Device resources\n");
+		res[RES_DEV_ID].start = pci_resource_start(pdev, PCI_BAR_DEV);
+		res[RES_DEV_ID].end =   pci_resource_end(pdev, PCI_BAR_DEV);
+		res[RES_DEV_ID].name = "dev";
+		res[RES_DEV_ID].flags = IORESOURCE_MEM;
+		dev_dbg(&pdev->dev, "USBSS-DEV physical base addr: %pa\n",
+			&res[RES_DEV_ID].start);
+
+		res[RES_HOST_ID].start = pci_resource_start(pdev, PCI_BAR_HOST);
+		res[RES_HOST_ID].end = pci_resource_end(pdev, PCI_BAR_HOST);
+		res[RES_HOST_ID].name = "xhci";
+		res[RES_HOST_ID].flags = IORESOURCE_MEM;
+		dev_dbg(&pdev->dev, "USBSS-XHCI physical base addr: %pa\n",
+			&res[RES_HOST_ID].start);
+
+		/* Interrupt for XHCI, */
+		wrap->dev_res[RES_IRQ_HOST_ID].start = pdev->irq;
+		wrap->dev_res[RES_IRQ_HOST_ID].name = "host";
+		wrap->dev_res[RES_IRQ_HOST_ID].flags = IORESOURCE_IRQ;
+
+		/* Interrupt device. It's the same as for HOST. */
+		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].start = pdev->irq;
+		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].name = "peripheral";
+		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].flags = IORESOURCE_IRQ;
+	} else {
+		res[RES_DRD_ID].start = pci_resource_start(pdev, PCI_BAR_OTG);
+		res[RES_DRD_ID].end =   pci_resource_end(pdev, PCI_BAR_OTG);
+		res[RES_DRD_ID].name = "otg";
+		res[RES_DRD_ID].flags = IORESOURCE_MEM;
+		dev_dbg(&pdev->dev, "CDNSP-DRD physical base addr: %pa\n",
+			&res[RES_DRD_ID].start);
+
+		/* Interrupt for OTG/DRD. */
+		wrap->dev_res[RES_IRQ_OTG_ID].start = pdev->irq;
+		wrap->dev_res[RES_IRQ_OTG_ID].name = "otg";
+		wrap->dev_res[RES_IRQ_OTG_ID].flags = IORESOURCE_IRQ;
+	}
+
+	if (pci_is_enabled(func)) {
+		/* Set up platform device info. */
+		memset(&plat_info, 0, sizeof(plat_info));
+		plat_info.parent = &pdev->dev;
+		plat_info.fwnode = pdev->dev.fwnode;
+		plat_info.name = PLAT_DRIVER_NAME;
+		plat_info.id = pdev->devfn;
+		wrap->devfn  = pdev->devfn;
+		plat_info.res = wrap->dev_res;
+		plat_info.num_res = ARRAY_SIZE(wrap->dev_res);
+		plat_info.dma_mask = pdev->dma_mask;
+		/* Register platform device. */
+		wrap->plat_dev = platform_device_register_full(&plat_info);
+		if (IS_ERR(wrap->plat_dev)) {
+			pci_disable_device(pdev);
+			err = PTR_ERR(wrap->plat_dev);
+			kfree(wrap);
+			return err;
+		}
+	}
+
+	pci_set_drvdata(pdev, wrap);
+	return err;
+}
+
+static void cdnsp_pci_remove(struct pci_dev *pdev)
+{
+	struct cdnsp_wrap *wrap;
+	struct pci_dev *func;
+
+	func = cdnsp_get_second_fun(pdev);
+
+	wrap = (struct cdnsp_wrap *)pci_get_drvdata(pdev);
+	if (wrap->devfn == pdev->devfn)
+		platform_device_unregister(wrap->plat_dev);
+
+	if (!pci_is_enabled(func))
+		kfree(wrap);
+}
+
+static const struct pci_device_id cdnsp_pci_ids[] = {
+	{ PCI_VENDOR_ID_CDNS, CDNS_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,
+	  PCI_CLASS_SERIAL_USB_DEVICE, PCI_ANY_ID },
+	{ PCI_VENDOR_ID_CDNS, CDNS_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,
+	  CDNS_DRD_IF, PCI_ANY_ID },
+	{ 0, }
+};
+
+static struct pci_driver cdnsp_pci_driver = {
+	.name = "cdnsp-pci",
+	.id_table = &cdnsp_pci_ids[0],
+	.probe = cdnsp_pci_probe,
+	.remove = cdnsp_pci_remove,
+};
+
+module_pci_driver(cdnsp_pci_driver);
+MODULE_DEVICE_TABLE(pci, cdnsp_pci_ids);
+
+MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Cadence CDNSP PCI Glue Layer");
-- 
2.17.1