diff options
Diffstat (limited to 'drivers/thunderbolt/acpi.c')
| -rw-r--r-- | drivers/thunderbolt/acpi.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/thunderbolt/acpi.c b/drivers/thunderbolt/acpi.c index 35fa17f7e599..b67e72d5644b 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); +} |