drivers/platform/x86/intel/wmi/thunderbolt.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * WMI Thunderbolt driver
   4  *
   5  * Copyright (C) 2017 Dell Inc. All Rights Reserved.
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/acpi.h>
  11 #include <linux/device.h>
  12 #include <linux/fs.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/string.h>
  16 #include <linux/sysfs.h>
  17 #include <linux/types.h>
  18 #include <linux/wmi.h>
  19
  20 #define INTEL_WMI_THUNDERBOLT_GUID "86CCFD48-205E-4A77-9C48-2021CBEDE341"
  21
  22 static ssize_t force_power_store(struct device *dev,
  23                                  struct device_attribute *attr,
  24                                  const char *buf, size_t count)
  25 {
  26         struct acpi_buffer input;
  27         acpi_status status;
  28         u8 mode;
  29
  30         input.length = sizeof(u8);
  31         input.pointer = &mode;
  32         mode = hex_to_bin(buf[0]);
  33         dev_dbg(dev, "force_power: storing %#x\n", mode);
  34         if (mode == 0 || mode == 1) {
  35                 status = wmidev_evaluate_method(to_wmi_device(dev), 0, 1, &input, NULL);
  36                 if (ACPI_FAILURE(status)) {
  37                         dev_dbg(dev, "force_power: failed to evaluate ACPI method\n");
  38                         return -ENODEV;
  39                 }
  40         } else {
  41                 dev_dbg(dev, "force_power: unsupported mode\n");
  42                 return -EINVAL;
  43         }
  44         return count;
  45 }
  46
  47 static DEVICE_ATTR_WO(force_power);
  48
  49 static struct attribute *tbt_attrs[] = {
  50         &dev_attr_force_power.attr,
  51         NULL
  52 };
  53 ATTRIBUTE_GROUPS(tbt);
  54
  55 static const struct wmi_device_id intel_wmi_thunderbolt_id_table[] = {
  56         { .guid_string = INTEL_WMI_THUNDERBOLT_GUID },
  57         { },
  58 };
  59
  60 static struct wmi_driver intel_wmi_thunderbolt_driver = {
  61         .driver = {
  62                 .name = "intel-wmi-thunderbolt",
  63                 .dev_groups = tbt_groups,
  64         },
  65         .id_table = intel_wmi_thunderbolt_id_table,
  66         .no_singleton = true,
  67 };
  68
  69 module_wmi_driver(intel_wmi_thunderbolt_driver);
  70
  71 MODULE_DEVICE_TABLE(wmi, intel_wmi_thunderbolt_id_table);
  72 MODULE_AUTHOR("Mario Limonciello <mario.limonciello@dell.com>");
  73 MODULE_DESCRIPTION("Intel WMI Thunderbolt force power driver");
  74 MODULE_LICENSE("GPL v2");