Current implementations of Intel Thunderbolt controllers will go
into a low power mode when not in use.
Many machines containing these controllers also have a GPIO wired up
that can force the controller awake. This is offered via a ACPI-WMI
interface intended to be manipulated by a userspace utility.
This mechanism is provided by Intel to OEMs to include in BIOS.
It uses an industry wide GUID that is populated in a separate _WDG
entry with no binary MOF.
This interface allow software such as fwupd to wake up thunderbolt
controllers to query the firmware version or flash new firmware.
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxxx>
---
MAINTAINERS | 5 ++
drivers/platform/x86/Kconfig | 13 ++++
drivers/platform/x86/Makefile | 1 +
drivers/platform/x86/intel-wmi-thunderbolt.c | 97 ++++++++++++++++++++++++++++
4 files changed, 116 insertions(+)
create mode 100644 drivers/platform/x86/intel-wmi-thunderbolt.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 1c3feff..375bea9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3949,6 +3949,11 @@ M: Pali Rohár <pali.rohar@xxxxxxxxx>
S: Maintained
F: drivers/platform/x86/dell-wmi.c
+INTEL WMI THUNDERBOLT DRIVER
+M: Mario Limonciello <mario.limonciello@xxxxxxxx>
+S: Maintained
+F: drivers/platform/x86/intel-wmi-thunderbolt.c
+
DELTA ST MEDIA DRIVER
M: Hugues Fruchet <hugues.fruchet@xxxxxx>
L: linux-media@xxxxxxxxxxxxxxx
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 80b8795..6670a8d 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -658,6 +658,19 @@ config WMI_BMOF
To compile this driver as a module, choose M here: the module will
be called wmi-bmof.
+config INTEL_WMI_THUNDERBOLT
+ tristate "Intel WMI thunderbolt driver"
+ depends on ACPI_WMI
+ default ACPI_WMI
+ ---help---
+ Say Y here if you want to be able to use the WMI interface on select
+ systems to force the power control of Intel Thunderbolt controllers.
+ This is useful for updating the firmware when devices are not plugged
+ into the controller.
+
+ To compile this driver as a module, choose M here: the module will
+ be called intel-wmi-thunderbolt.
+
config MSI_WMI
tristate "MSI WMI extras"
depends on ACPI_WMI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 91cec17..2b315d0 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_PEAQ_WMI) += peaq-wmi.o
obj-$(CONFIG_SURFACE3_WMI) += surface3-wmi.o
obj-$(CONFIG_TOPSTAR_LAPTOP) += topstar-laptop.o
obj-$(CONFIG_WMI_BMOF) += wmi-bmof.o
+obj-$(CONFIG_INTEL_WMI_THUNDERBOLT) += intel-wmi-thunderbolt.o
# toshiba_acpi must link after wmi to ensure that wmi devices are found
# before toshiba_acpi initializes
diff --git a/drivers/platform/x86/intel-wmi-thunderbolt.c b/drivers/platform/x86/intel-wmi-thunderbolt.c
new file mode 100644
index 0000000..98f60f2
--- /dev/null
+++ b/drivers/platform/x86/intel-wmi-thunderbolt.c
@@ -0,0 +1,97 @@
+/*
+ * WMI Thunderbolt driver
+ *
+ * Copyright (C) 2017 Dell Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/wmi.h>
+
+#define INTEL_WMI_THUNDERBOLT_GUID "86CCFD48-205E-4A77-9C48-2021CBEDE341"
+
+
+static ssize_t force_power_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct acpi_buffer input;
+ acpi_status status;
+ u8 mode;
+
+ input.length = (acpi_size) (sizeof(u8));
+ input.pointer = &mode;
+ mode = hex_to_bin(buf[0]);
+ if (mode == 0 || mode == 1) {
+ status = wmi_evaluate_method(INTEL_WMI_THUNDERBOLT_GUID, 0, 1,
+ &input, NULL);
+ if (ACPI_FAILURE(status)) {
+ pr_err("intel-wmi-thunderbolt: failed setting %s\n",
+ buf);
+ return -ENODEV;
+ }
+ } else {
+ pr_err("intel-wmi-thunderbolt: unsupported mode: %d", mode);
+ }
+ return count;
+}
+
+static DEVICE_ATTR_WO(force_power);
+
+static struct attribute *tbt_attrs[] = {
+ &dev_attr_force_power.attr,
+ NULL
+};
+
+static const struct attribute_group tbt_attribute_group = {
+ .attrs = tbt_attrs,
+};
+
+static int intel_wmi_thunderbolt_probe(struct wmi_device *wdev)
+{
+ return sysfs_create_group(&wdev->dev.kobj, &tbt_attribute_group);
+}
+
+static int intel_wmi_thunderbolt_remove(struct wmi_device *wdev)
+{
+ sysfs_remove_group(&wdev->dev.kobj, &tbt_attribute_group);
+ return 0;
+}
+
+static const struct wmi_device_id intel_wmi_thunderbolt_id_table[] = {
+ { .guid_string = INTEL_WMI_THUNDERBOLT_GUID },
+ { },
+};
+
+static struct wmi_driver intel_wmi_thunderbolt_driver = {
+ .driver = {
+ .name = "intel-wmi-thunderbolt",
+ },
+ .probe = intel_wmi_thunderbolt_probe,
+ .remove = intel_wmi_thunderbolt_remove,
+ .id_table = intel_wmi_thunderbolt_id_table,
+};
+
+module_wmi_driver(intel_wmi_thunderbolt_driver);
+
+MODULE_ALIAS("wmi:" INTEL_WMI_THUNDERBOLT_GUID);
+MODULE_AUTHOR("Mario Limonciello <mario.limonciello@xxxxxxxx>");
+MODULE_DESCRIPTION("Intel WMI Thunderbolt force power driver");
+MODULE_LICENSE("GPL");
--
2.7.4
