1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * XHCI extended capability handling
  4 *
  5 * Copyright (c) 2017 Hans de Goede <hdegoede@redhat.com>
  6 */
  7
  8#include <linux/platform_device.h>
  9#include <linux/property.h>
 10#include <linux/pci.h>
 11#include "xhci.h"
 12
 13#define USB_SW_DRV_NAME		"intel_xhci_usb_sw"
 14#define USB_SW_RESOURCE_SIZE	0x400
 15
 16#define PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI	0x22b5
 17
 18static const struct property_entry role_switch_props[] = {
 19	PROPERTY_ENTRY_BOOL("sw_switch_disable"),
 20	{},
 21};
 22
 23static void xhci_intel_unregister_pdev(void *arg)
 24{
 25	platform_device_unregister(arg);
 26}
 27
 28static int xhci_create_intel_xhci_sw_pdev(struct xhci_hcd *xhci, u32 cap_offset)
 29{
 30	struct usb_hcd *hcd = xhci_to_hcd(xhci);
 31	struct device *dev = hcd->self.controller;
 32	struct platform_device *pdev;
 33	struct pci_dev *pci = to_pci_dev(dev);
 34	struct resource	res = { 0, };
 35	int ret;
 36
 37	pdev = platform_device_alloc(USB_SW_DRV_NAME, PLATFORM_DEVID_NONE);
 38	if (!pdev) {
 39		xhci_err(xhci, "couldn't allocate %s platform device\n",
 40			 USB_SW_DRV_NAME);
 41		return -ENOMEM;
 42	}
 43
 44	res.start = hcd->rsrc_start + cap_offset;
 45	res.end	  = res.start + USB_SW_RESOURCE_SIZE - 1;
 46	res.name  = USB_SW_DRV_NAME;
 47	res.flags = IORESOURCE_MEM;
 48
 49	ret = platform_device_add_resources(pdev, &res, 1);
 50	if (ret) {
 51		dev_err(dev, "couldn't add resources to intel_xhci_usb_sw pdev\n");
 52		platform_device_put(pdev);
 53		return ret;
 54	}
 55
 56	if (pci->device == PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI) {
 57		ret = device_create_managed_software_node(&pdev->dev, role_switch_props,
 58							  NULL);
 59		if (ret) {
 60			dev_err(dev, "failed to register device properties\n");
 61			platform_device_put(pdev);
 62			return ret;
 63		}
 64	}
 65
 66	pdev->dev.parent = dev;
 67
 68	ret = platform_device_add(pdev);
 69	if (ret) {
 70		dev_err(dev, "couldn't register intel_xhci_usb_sw pdev\n");
 71		platform_device_put(pdev);
 72		return ret;
 73	}
 74
 75	ret = devm_add_action_or_reset(dev, xhci_intel_unregister_pdev, pdev);
 76	if (ret) {
 77		dev_err(dev, "couldn't add unregister action for intel_xhci_usb_sw pdev\n");
 78		return ret;
 79	}
 80
 81	return 0;
 82}
 83
 84int xhci_ext_cap_init(struct xhci_hcd *xhci)
 85{
 86	void __iomem *base = &xhci->cap_regs->hc_capbase;
 87	u32 offset, val;
 88	int ret;
 89
 90	offset = xhci_find_next_ext_cap(base, 0, 0);
 91
 92	while (offset) {
 93		val = readl(base + offset);
 94
 95		switch (XHCI_EXT_CAPS_ID(val)) {
 96		case XHCI_EXT_CAPS_VENDOR_INTEL:
 97			if (xhci->quirks & XHCI_INTEL_USB_ROLE_SW) {
 98				ret = xhci_create_intel_xhci_sw_pdev(xhci,
 99								     offset);
100				if (ret)
101					return ret;
102			}
103			break;
104		}
105		offset = xhci_find_next_ext_cap(base, offset, 0);
106	}
107
108	return 0;
109}
110EXPORT_SYMBOL_GPL(xhci_ext_cap_init);