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: &res, num: 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(dev: &pdev->dev, properties: 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, start: 0, id: 0);
91
92 while (offset) {
93 val = readl(addr: 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 cap_offset: offset);
100 if (ret)
101 return ret;
102 }
103 break;
104 }
105 offset = xhci_find_next_ext_cap(base, start: offset, id: 0);
106 }
107
108 return 0;
109}
110EXPORT_SYMBOL_GPL(xhci_ext_cap_init);
111

source code of linux/drivers/usb/host/xhci-ext-caps.c