// SPDX-License-Identifier: GPL-2.0
/*
* ACPI support
*
* Copyright (C) 2020, Intel Corporation
* Author: Mika Westerberg <mika.westerberg@linux.intel.com>
*/
#include <linux/acpi.h>
#include <linux/pm_runtime.h>
#include "tb.h"
static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data,
void **return_value)
{
struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
struct fwnode_handle *fwnode;
struct tb_nhi *nhi = data;
struct pci_dev *pdev;
struct device *dev;
if (!adev)
return AE_OK;
fwnode = fwnode_find_reference(acpi_fwnode_handle(adev), "usb4-host-interface", 0);
if (IS_ERR(fwnode))
return AE_OK;
/* It needs to reference this NHI */
if (dev_fwnode(&nhi->pdev->dev) != fwnode)
goto out_put;
/*
* Try to find physical device walking upwards to the hierarcy.
* We need to do this because the xHCI driver might not yet be
* bound so the USB3 SuperSpeed ports are not yet created.
*/
do {
dev = acpi_get_first_physical_node(adev);
if (dev)
break;
adev = acpi_dev_parent(adev);
} while (adev);
/*
* Check that the device is PCIe. This is because USB3
* SuperSpeed ports have this property and they are not power
* managed with the xHCI and the SuperSpeed hub so we create the
* link from xHCI instead.
*/
while (dev && !dev_is_pci(dev))
dev = dev->parent;
if (!dev)
goto out_put;
/*
* Check that this actually matches the type of device we
* expect. It should either be xHCI or PCIe root/downstream
* port.
*/
pdev = to_pci_dev(dev);
if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI ||
(pci_is_pcie(pdev) &&
(pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ||
pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM))) {
const struct device_link *link;
/*
* Make them both active first to make sure the NHI does
* not runtime suspend before the consumer. The
* pm_runtime_put() below then allows the consumer to
* runtime suspend again (which then allows NHI runtime
* suspend too now that the device link is established).
*/
pm_runtime_get_sync(&pdev->dev);
link = device_link_add(&pdev->dev, &nhi->pdev->dev,
DL_FLAG_AUTOREMOVE_SUPPLIER |
DL_FLAG_RPM_ACTIVE |
DL_FLAG_PM_RUNTIME);
if (link) {
dev_dbg(&nhi->pdev->dev, "created link from %s\n",
dev_name(&pdev->dev));
} else {
dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
dev_name(&pdev->dev));
}
pm_runtime_put(&pdev->dev);
}
out_put:
fwnode_handle_put(fwnode);
return AE_OK;
}
/**
* tb_acpi_add_links() - Add device links based on ACPI description
* @nhi: Pointer to NHI
*
* Goes over ACPI namespace finding tunneled ports that reference to
* @nhi ACPI node. For each reference a device link is added. The link
* is automatically removed by the driver core.
*/
void tb_acpi_add_links(struct tb_nhi *nhi)
{
acpi_status status;
if (!has_acpi_companion(&nhi->pdev->dev))
return;
/*
* Find all devices that have usb4-host-controller interface
* property that references to this NHI.
*/
status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, 32,
tb_acpi_add_link, NULL, nhi, NULL);
if (ACPI_FAILURE(status))
dev_warn(&nhi->pdev->dev, "failed to enumerate tunneled ports\n");
}
/**
* tb_acpi_is_native() - Did the platform grant native TBT/USB4 control
*
* Returns %true if the platform granted OS native control over
* TBT/USB4. In this case software based connection manager can be used,
* otherwise there is firmware based connection manager running.
*/
bool tb_acpi_is_native(void)
{
return osc_sb_native_usb4_support_confirmed &&
osc_sb_native_usb4_control;
}
/**
* tb_acpi_may_tunnel_usb3() - Is USB3 tunneling allowed by the platform
*
* When software based connection manager is used, this function
* returns %true if platform allows native USB3 tunneling.
*/
bool tb_acpi_may_tunnel_usb3(void)
{
if (tb_acpi_is_native())
return osc_sb_native_usb4_control & OSC_USB_USB3_TUNNELING;
return true;
}
/**
* tb_acpi_may_tunnel_dp() - Is DisplayPort tunneling allowed by the platform
*
* When software based connection manager is used, this function
* returns %true if platform allows native DP tunneling.
*/
bool tb_acpi_may_tunnel_dp(void)
{
if (tb_acpi_is_native())
return osc_sb_native_usb4_control & OSC_USB_DP_TUNNELING;
return true;
}
/**
* tb_acpi_may_tunnel_pcie() - Is PCIe tunneling allowed by the platform
*
* When software based connection manager is used, this function
* returns %true if platform allows native PCIe tunneling.
*/
bool tb_acpi_may_tunnel_pcie(void)
{
if (tb_acpi_is_native())
return osc_sb_native_usb4_control & OSC_USB_PCIE_TUNNELING;
return true;
}
/**
* tb_acpi_is_xdomain_allowed() - Are XDomain connections allowed
*
* When software based connection manager is used, this function
* returns %true if platform allows XDomain connections.
*/
bool tb_acpi_is_xdomain_allowed(void)
{
if (tb_acpi_is_native())
return osc_sb_native_usb4_control & OSC_USB_XDOMAIN;
return true;
}
/* UUID for retimer _DSM: e0053122-795b-4122-8a5e-57be1d26acb3 */
static const guid_t retimer_dsm_guid =
GUID_INIT(0xe0053122, 0x795b, 0x4122,
0x8a, 0x5e, 0x57, 0xbe, 0x1d, 0x26, 0xac, 0xb3);
#define RETIMER_DSM_QUERY_ONLINE_STATE 1
#define RETIMER_DSM_SET_ONLINE_STATE 2
static int tb_acpi_retimer_set_power(struct tb_port *port, bool power)
{
struct usb4_port *usb4 = port->usb4;
union acpi_object argv4[2];
struct acpi_device *adev;
union acpi_object *obj;
int ret;
if (!usb4->can_offline)
return 0;
adev = ACPI_COMPANION(&usb4->dev);
if (WARN_ON(!adev))
return 0;
/* Check if we are already powered on (and in correct mode) */
obj = acpi_evaluate_dsm_typed(adev->handle, &retimer_dsm_guid, 1,
RETIMER_DSM_QUERY_ONLINE_STATE, NULL,
ACPI_TYPE_INTEGER);
if (!obj) {
tb_port_warn(port, "ACPI: query online _DSM failed\n");
return -EIO;
}
ret = obj->integer.value;
ACPI_FREE(obj);
if (power == ret)
return 0;
tb_port_dbg(port, "ACPI: calling _DSM to power %s retimers\n",
power ? "on" : "off");
argv4[0].type = ACPI_TYPE_PACKAGE;
argv4[0].package.count = 1;
argv4[0].package.elements = &argv4[1];
argv4[1].integer.type = ACPI_TYPE_INTEGER;
argv4[1].integer.value = power;
obj = acpi_evaluate_dsm_typed(adev->handle, &retimer_dsm_guid, 1,
RETIMER_DSM_SET_ONLINE_STATE, argv4,
ACPI_TYPE_INTEGER);
if (!obj) {
tb_port_warn(port,
"ACPI: set online state _DSM evaluation failed\n");
return -EIO;
}
ret = obj->integer.value;
ACPI_FREE(obj);
if (ret >= 0) {
if (power)
return ret == 1 ? 0 : -EBUSY;
return 0;
}
tb_port_warn(port, "ACPI: set online state _DSM failed with error %d\n", ret);
return -EIO;
}
/**
* tb_acpi_power_on_retimers() - Call platform to power on retimers
* @port: USB4 port
*
* Calls platform to turn on power to all retimers behind this USB4
* port. After this function returns successfully the caller can
* continue with the normal retimer flows (as specified in the USB4
* spec). Note if this returns %-EBUSY it means the type-C port is in
* non-USB4/TBT mode (there is non-USB4/TBT device connected).
*
* This should only be called if the USB4/TBT link is not up.
*
* Returns %0 on success.
*/
int tb_acpi_power_on_retimers(struct tb_port *port)
{
return tb_acpi_retimer_set_power(port, true);
}
/**
* tb_acpi_power_off_retimers() - Call platform to power off retimers
* @port: USB4 port
*
* This is the opposite of tb_acpi_power_on_retimers(). After returning
* successfully the normal operations with the @port can continue.
*
* Returns %0 on success.
*/
int tb_acpi_power_off_retimers(struct tb_port *port)
{
return tb_acpi_retimer_set_power(port, false);
}
static bool tb_acpi_bus_match(struct device *dev)
{
return tb_is_switch(dev) || tb_is_usb4_port_device(dev);
}
static struct acpi_device *tb_acpi_switch_find_companion(struct tb_switch *sw)
{
struct acpi_device *adev = NULL;
struct tb_switch *parent_sw;
/*
* Device routers exists under the downstream facing USB4 port
* of the parent router. Their _ADR is always 0.
*/
parent_sw = tb_switch_parent(sw);
if (parent_sw) {
struct tb_port *port = tb_port_at(tb_route(sw), parent_sw);
struct acpi_device *port_adev;
port_adev = acpi_find_child_by_adr(ACPI_COMPANION(&parent_sw->dev),
port->port);
if (port_adev)
adev = acpi_find_child_device(port_adev, 0, false);
} else {
struct tb_nhi *nhi = sw->tb->nhi;
struct acpi_device *parent_adev;
parent_adev = ACPI_COMPANION(&nhi->pdev->dev);
if (parent_adev)
adev = acpi_find_child_device(parent_adev, 0, false);
}
return adev;
}
static struct acpi_device *tb_acpi_find_companion(struct device *dev)
{
/*
* The Thunderbolt/USB4 hierarchy looks like following:
*
* Device (NHI)
* Device (HR) // Host router _ADR == 0
* Device (DFP0) // Downstream port _ADR == lane 0 adapter
* Device (DR) // Device router _ADR == 0
* Device (UFP) // Upstream port _ADR == lane 0 adapter
* Device (DFP1) // Downstream port _ADR == lane 0 adapter number
*
* At the moment we bind the host router to the corresponding
* Linux device.
*/
if (tb_is_switch(dev))
return tb_acpi_switch_find_companion(tb_to_switch(dev));
if (tb_is_usb4_port_device(dev))
return acpi_find_child_by_adr(ACPI_COMPANION(dev->parent),
tb_to_usb4_port_device(dev)->port->port);
return NULL;
}
static void tb_acpi_setup(struct device *dev)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
struct usb4_port *usb4 = tb_to_usb4_port_device(dev);
if (!adev || !usb4)
return;
if (acpi_check_dsm(adev->handle, &retimer_dsm_guid, 1,
BIT(RETIMER_DSM_QUERY_ONLINE_STATE) |
BIT(RETIMER_DSM_SET_ONLINE_STATE)))
usb4->can_offline = true;
}
static struct acpi_bus_type tb_acpi_bus = {
.name = "thunderbolt",
.match = tb_acpi_bus_match,
.find_companion = tb_acpi_find_companion,
.setup = tb_acpi_setup,
};
int tb_acpi_init(void)
{
return register_acpi_bus_type(&tb_acpi_bus);
}
void tb_acpi_exit(void)
{
unregister_acpi_bus_type(&tb_acpi_bus);
}
