diff --git a/drivers/thunderbolt/acpi.c b/drivers/thunderbolt/acpi.c
index 35fa17f7e59983f90ec022b9415f95d212542148..b67e72d5644b3b9d5c7234d818c745fdb9fd6162 100644
--- a/drivers/thunderbolt/acpi.c
+++ b/drivers/thunderbolt/acpi.c
@@ -180,3 +180,209 @@ bool tb_acpi_is_xdomain_allowed(void)
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_find_port(struct acpi_device *adev,
+ const struct tb_port *port)
+{
+ struct acpi_device *port_adev;
+
+ if (!adev)
+ return NULL;
+
+ /*
+ * Device routers exists under the downstream facing USB4 port
+ * of the parent router. Their _ADR is always 0.
+ */
+ list_for_each_entry(port_adev, &adev->children, node) {
+ if (acpi_device_adr(port_adev) == port->port)
+ return port_adev;
+ }
+
+ return NULL;
+}
+
+static struct acpi_device *tb_acpi_switch_find_companion(struct tb_switch *sw)
+{
+ struct acpi_device *adev = NULL;
+ struct tb_switch *parent_sw;
+
+ 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 = tb_acpi_find_port(ACPI_COMPANION(&parent_sw->dev), 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));
+ else if (tb_is_usb4_port_device(dev))
+ return tb_acpi_find_port(ACPI_COMPANION(dev->parent),
+ tb_to_usb4_port_device(dev)->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);
+}
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c
index 98f4056f89ffe7b6f6d544eb9a25feb806f157e8..a062befcb3b2c324df00b6755e8d130cccf33db2 100644
--- a/drivers/thunderbolt/domain.c
+++ b/drivers/thunderbolt/domain.c
@@ -881,11 +881,12 @@ int tb_domain_init(void)
int ret;
tb_test_init();
-
tb_debugfs_init();
+ tb_acpi_init();
+
ret = tb_xdomain_init();
if (ret)
- goto err_debugfs;
+ goto err_acpi;
ret = bus_register(&tb_bus_type);
if (ret)
goto err_xdomain;
@@ -894,7 +895,8 @@ int tb_domain_init(void)
err_xdomain:
tb_xdomain_exit();
-err_debugfs:
+err_acpi:
+ tb_acpi_exit();
tb_debugfs_exit();
tb_test_exit();
@@ -907,6 +909,7 @@ void tb_domain_exit(void)
ida_destroy(&tb_domain_ida);
tb_nvm_exit();
tb_xdomain_exit();
+ tb_acpi_exit();
tb_debugfs_exit();
tb_test_exit();
}
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 948e7601428f96461b0009081acc0d15be42ed88..c5704f495afa94daab792d958e131d0b85ca5949 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -247,10 +247,13 @@ struct tb_port {
* struct usb4_port - USB4 port device
* @dev: Device for the port
* @port: Pointer to the lane 0 adapter
+ * @can_offline: Does the port have necessary platform support to moved
+ * it into offline mode and back
*/
struct usb4_port {
struct device dev;
struct tb_port *port;
+ bool can_offline;
};
/**
@@ -1113,6 +1116,11 @@ bool tb_acpi_may_tunnel_usb3(void);
bool tb_acpi_may_tunnel_dp(void);
bool tb_acpi_may_tunnel_pcie(void);
bool tb_acpi_is_xdomain_allowed(void);
+
+int tb_acpi_init(void);
+void tb_acpi_exit(void);
+int tb_acpi_power_on_retimers(struct tb_port *port);
+int tb_acpi_power_off_retimers(struct tb_port *port);
#else
static inline void tb_acpi_add_links(struct tb_nhi *nhi) { }
@@ -1121,6 +1129,11 @@ static inline bool tb_acpi_may_tunnel_usb3(void) { return true; }
static inline bool tb_acpi_may_tunnel_dp(void) { return true; }
static inline bool tb_acpi_may_tunnel_pcie(void) { return true; }
static inline bool tb_acpi_is_xdomain_allowed(void) { return true; }
+
+static inline int tb_acpi_init(void) { return 0; }
+static inline void tb_acpi_exit(void) { }
+static inline int tb_acpi_power_on_retimers(struct tb_port *port) { return 0; }
+static inline int tb_acpi_power_off_retimers(struct tb_port *port) { return 0; }
#endif
#ifdef CONFIG_DEBUG_FS