mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 10:40:15 +02:00 
			
		
		
		
	Some users have been reporting issues with thunderbolt being turned off before fully initialized. This is suspected to be caused by userspace turning off the Thunderbolt controller using intel-wmi-thunderbolt prematurely. Userspace has already made some mitigations for this situation: https://github.com/hughsie/fwupd/commit/ef6f1d76983c9b66 https://github.com/hughsie/fwupd/commit/c07ce5b4889a5384 To allow easier debugging of this situation add output that can be turned on with dynamic debugging to better root cause this problem. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199631 BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=201227 Suggested-by: Mika Westerberg <mika.westerberg@intel.com> Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
		
			
				
	
	
		
			94 lines
		
	
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			94 lines
		
	
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
 | 
						|
/*
 | 
						|
 * WMI Thunderbolt driver
 | 
						|
 *
 | 
						|
 * Copyright (C) 2017 Dell Inc. All Rights Reserved.
 | 
						|
 */
 | 
						|
 | 
						|
#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 = sizeof(u8);
 | 
						|
	input.pointer = &mode;
 | 
						|
	mode = hex_to_bin(buf[0]);
 | 
						|
	dev_dbg(dev, "force_power: storing %#x\n", mode);
 | 
						|
	if (mode == 0 || mode == 1) {
 | 
						|
		status = wmi_evaluate_method(INTEL_WMI_THUNDERBOLT_GUID, 0, 1,
 | 
						|
					     &input, NULL);
 | 
						|
		if (ACPI_FAILURE(status)) {
 | 
						|
			dev_dbg(dev, "force_power: failed to evaluate ACPI method\n");
 | 
						|
			return -ENODEV;
 | 
						|
		}
 | 
						|
	} else {
 | 
						|
		dev_dbg(dev, "force_power: unsupported mode\n");
 | 
						|
		return -EINVAL;
 | 
						|
	}
 | 
						|
	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)
 | 
						|
{
 | 
						|
	int ret;
 | 
						|
 | 
						|
	ret = sysfs_create_group(&wdev->dev.kobj, &tbt_attribute_group);
 | 
						|
	kobject_uevent(&wdev->dev.kobj, KOBJ_CHANGE);
 | 
						|
	return ret;
 | 
						|
}
 | 
						|
 | 
						|
static int intel_wmi_thunderbolt_remove(struct wmi_device *wdev)
 | 
						|
{
 | 
						|
	sysfs_remove_group(&wdev->dev.kobj, &tbt_attribute_group);
 | 
						|
	kobject_uevent(&wdev->dev.kobj, KOBJ_CHANGE);
 | 
						|
	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@dell.com>");
 | 
						|
MODULE_DESCRIPTION("Intel WMI Thunderbolt force power driver");
 | 
						|
MODULE_LICENSE("GPL v2");
 |