1 // SPDX-License-Identifier: GPL-2.0
5 * Copyright (C) 2020, Intel Corporation
6 * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
9 #include <linux/acpi.h>
13 static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data,
16 struct fwnode_reference_args args;
17 struct fwnode_handle *fwnode;
18 struct tb_nhi *nhi = data;
19 struct acpi_device *adev;
24 if (acpi_bus_get_device(handle, &adev))
27 fwnode = acpi_fwnode_handle(adev);
28 ret = fwnode_property_get_reference_args(fwnode, "usb4-host-interface",
33 /* It needs to reference this NHI */
34 if (nhi->pdev->dev.fwnode != args.fwnode)
38 * Try to find physical device walking upwards to the hierarcy.
39 * We need to do this because the xHCI driver might not yet be
40 * bound so the USB3 SuperSpeed ports are not yet created.
42 dev = acpi_get_first_physical_node(adev);
47 dev = acpi_get_first_physical_node(adev);
54 * Check that the device is PCIe. This is because USB3
55 * SuperSpeed ports have this property and they are not power
56 * managed with the xHCI and the SuperSpeed hub so we create the
57 * link from xHCI instead.
59 while (dev && !dev_is_pci(dev))
66 * Check that this actually matches the type of device we
67 * expect. It should either be xHCI or PCIe root/downstream
70 pdev = to_pci_dev(dev);
71 if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI ||
73 (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ||
74 pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM))) {
75 const struct device_link *link;
77 link = device_link_add(&pdev->dev, &nhi->pdev->dev,
78 DL_FLAG_AUTOREMOVE_SUPPLIER |
81 dev_dbg(&nhi->pdev->dev, "created link from %s\n",
82 dev_name(&pdev->dev));
84 dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
85 dev_name(&pdev->dev));
90 fwnode_handle_put(args.fwnode);
95 * tb_acpi_add_links() - Add device links based on ACPI description
96 * @nhi: Pointer to NHI
98 * Goes over ACPI namespace finding tunneled ports that reference to
99 * @nhi ACPI node. For each reference a device link is added. The link
100 * is automatically removed by the driver core.
102 void tb_acpi_add_links(struct tb_nhi *nhi)
106 if (!has_acpi_companion(&nhi->pdev->dev))
110 * Find all devices that have usb4-host-controller interface
111 * property that references to this NHI.
113 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, 32,
114 tb_acpi_add_link, NULL, nhi, NULL);
115 if (ACPI_FAILURE(status))
116 dev_warn(&nhi->pdev->dev, "failed to enumerate tunneled ports\n");
120 * tb_acpi_is_native() - Did the platform grant native TBT/USB4 control
122 * Returns %true if the platform granted OS native control over
123 * TBT/USB4. In this case software based connection manager can be used,
124 * otherwise there is firmware based connection manager running.
126 bool tb_acpi_is_native(void)
128 return osc_sb_native_usb4_support_confirmed &&
129 osc_sb_native_usb4_control;
133 * tb_acpi_may_tunnel_usb3() - Is USB3 tunneling allowed by the platform
135 * When software based connection manager is used, this function
136 * returns %true if platform allows native USB3 tunneling.
138 bool tb_acpi_may_tunnel_usb3(void)
140 if (tb_acpi_is_native())
141 return osc_sb_native_usb4_control & OSC_USB_USB3_TUNNELING;
146 * tb_acpi_may_tunnel_dp() - Is DisplayPort tunneling allowed by the platform
148 * When software based connection manager is used, this function
149 * returns %true if platform allows native DP tunneling.
151 bool tb_acpi_may_tunnel_dp(void)
153 if (tb_acpi_is_native())
154 return osc_sb_native_usb4_control & OSC_USB_DP_TUNNELING;
159 * tb_acpi_may_tunnel_pcie() - Is PCIe tunneling allowed by the platform
161 * When software based connection manager is used, this function
162 * returns %true if platform allows native PCIe tunneling.
164 bool tb_acpi_may_tunnel_pcie(void)
166 if (tb_acpi_is_native())
167 return osc_sb_native_usb4_control & OSC_USB_PCIE_TUNNELING;
172 * tb_acpi_is_xdomain_allowed() - Are XDomain connections allowed
174 * When software based connection manager is used, this function
175 * returns %true if platform allows XDomain connections.
177 bool tb_acpi_is_xdomain_allowed(void)
179 if (tb_acpi_is_native())
180 return osc_sb_native_usb4_control & OSC_USB_XDOMAIN;