166 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * lenovo-ymc.c - Lenovo Yoga Mode Control driver4 *5 * Copyright © 2022 Gergo Koteles <soyer@irl.hu>6 */7 8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt9 10#include <linux/acpi.h>11#include <linux/dmi.h>12#include <linux/input.h>13#include <linux/input/sparse-keymap.h>14#include <linux/wmi.h>15#include "ideapad-laptop.h"16 17#define LENOVO_YMC_EVENT_GUID "06129D99-6083-4164-81AD-F092F9D773A6"18#define LENOVO_YMC_QUERY_GUID "09B0EE6E-C3FD-4243-8DA1-7911FF80BB8C"19 20#define LENOVO_YMC_QUERY_INSTANCE 021#define LENOVO_YMC_QUERY_METHOD 0x0122 23static bool force;24module_param(force, bool, 0444);25MODULE_PARM_DESC(force, "Force loading on boards without a convertible DMI chassis-type");26 27static const struct dmi_system_id allowed_chasis_types_dmi_table[] = {28 {29 .matches = {30 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */),31 },32 },33 {34 .matches = {35 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */),36 },37 },38 { }39};40 41struct lenovo_ymc_private {42 struct input_dev *input_dev;43};44 45static const struct key_entry lenovo_ymc_keymap[] = {46 /* Ignore the uninitialized state */47 { KE_IGNORE, 0x00 },48 /* Laptop */49 { KE_SW, 0x01, { .sw = { SW_TABLET_MODE, 0 } } },50 /* Tablet */51 { KE_SW, 0x02, { .sw = { SW_TABLET_MODE, 1 } } },52 /* Drawing Board */53 { KE_SW, 0x03, { .sw = { SW_TABLET_MODE, 1 } } },54 /* Tent */55 { KE_SW, 0x04, { .sw = { SW_TABLET_MODE, 1 } } },56 { KE_END },57};58 59static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data)60{61 struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev);62 u32 input_val = 0;63 struct acpi_buffer input = { sizeof(input_val), &input_val };64 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };65 union acpi_object *obj;66 acpi_status status;67 int code;68 69 status = wmi_evaluate_method(LENOVO_YMC_QUERY_GUID,70 LENOVO_YMC_QUERY_INSTANCE,71 LENOVO_YMC_QUERY_METHOD,72 &input, &output);73 74 if (ACPI_FAILURE(status)) {75 dev_warn(&wdev->dev,76 "Failed to evaluate query method: %s\n",77 acpi_format_exception(status));78 return;79 }80 81 obj = output.pointer;82 83 if (obj->type != ACPI_TYPE_INTEGER) {84 dev_warn(&wdev->dev,85 "WMI event data is not an integer\n");86 goto free_obj;87 }88 code = obj->integer.value;89 90 if (!sparse_keymap_report_event(priv->input_dev, code, 1, true))91 dev_warn(&wdev->dev, "Unknown key %d pressed\n", code);92 93free_obj:94 kfree(obj);95 ideapad_laptop_call_notifier(IDEAPAD_LAPTOP_YMC_EVENT, &code);96}97 98static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)99{100 struct lenovo_ymc_private *priv;101 struct input_dev *input_dev;102 int err;103 104 if (!dmi_check_system(allowed_chasis_types_dmi_table)) {105 if (force)106 dev_info(&wdev->dev, "Force loading Lenovo YMC support\n");107 else108 return -ENODEV;109 }110 111 priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL);112 if (!priv)113 return -ENOMEM;114 115 input_dev = devm_input_allocate_device(&wdev->dev);116 if (!input_dev)117 return -ENOMEM;118 119 input_dev->name = "Lenovo Yoga Tablet Mode Control switch";120 input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0";121 input_dev->id.bustype = BUS_HOST;122 input_dev->dev.parent = &wdev->dev;123 err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL);124 if (err) {125 dev_err(&wdev->dev,126 "Could not set up input device keymap: %d\n", err);127 return err;128 }129 130 err = input_register_device(input_dev);131 if (err) {132 dev_err(&wdev->dev,133 "Could not register input device: %d\n", err);134 return err;135 }136 137 priv->input_dev = input_dev;138 dev_set_drvdata(&wdev->dev, priv);139 140 /* Report the state for the first time on probe */141 lenovo_ymc_notify(wdev, NULL);142 return 0;143}144 145static const struct wmi_device_id lenovo_ymc_wmi_id_table[] = {146 { .guid_string = LENOVO_YMC_EVENT_GUID },147 { }148};149MODULE_DEVICE_TABLE(wmi, lenovo_ymc_wmi_id_table);150 151static struct wmi_driver lenovo_ymc_driver = {152 .driver = {153 .name = "lenovo-ymc",154 },155 .id_table = lenovo_ymc_wmi_id_table,156 .probe = lenovo_ymc_probe,157 .notify = lenovo_ymc_notify,158};159 160module_wmi_driver(lenovo_ymc_driver);161 162MODULE_AUTHOR("Gergo Koteles <soyer@irl.hu>");163MODULE_DESCRIPTION("Lenovo Yoga Mode Control driver");164MODULE_LICENSE("GPL");165MODULE_IMPORT_NS(IDEAPAD_LAPTOP);166