1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * lenovo-ymc.c - Lenovo Yoga Mode Control driver 4 * 5 * Copyright © 2022 Gergo Koteles <soyer@irl.hu> 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 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 0 21 #define LENOVO_YMC_QUERY_METHOD 0x01 22 23 static bool ec_trigger __read_mostly; 24 module_param(ec_trigger, bool, 0444); 25 MODULE_PARM_DESC(ec_trigger, "Enable EC triggering work-around to force emitting tablet mode events"); 26 27 static const struct dmi_system_id ec_trigger_quirk_dmi_table[] = { 28 { 29 /* Lenovo Yoga 7 14ARB7 */ 30 .matches = { 31 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 32 DMI_MATCH(DMI_PRODUCT_NAME, "82QF"), 33 }, 34 }, 35 { } 36 }; 37 38 struct lenovo_ymc_private { 39 struct input_dev *input_dev; 40 struct acpi_device *ec_acpi_dev; 41 }; 42 43 static void lenovo_ymc_trigger_ec(struct wmi_device *wdev, struct lenovo_ymc_private *priv) 44 { 45 int err; 46 47 if (!priv->ec_acpi_dev) 48 return; 49 50 err = write_ec_cmd(priv->ec_acpi_dev->handle, VPCCMD_W_YMC, 1); 51 if (err) 52 dev_warn(&wdev->dev, "Could not write YMC: %d\n", err); 53 } 54 55 static const struct key_entry lenovo_ymc_keymap[] = { 56 /* Laptop */ 57 { KE_SW, 0x01, { .sw = { SW_TABLET_MODE, 0 } } }, 58 /* Tablet */ 59 { KE_SW, 0x02, { .sw = { SW_TABLET_MODE, 1 } } }, 60 /* Drawing Board */ 61 { KE_SW, 0x03, { .sw = { SW_TABLET_MODE, 1 } } }, 62 /* Tent */ 63 { KE_SW, 0x04, { .sw = { SW_TABLET_MODE, 1 } } }, 64 { KE_END }, 65 }; 66 67 static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data) 68 { 69 struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev); 70 u32 input_val = 0; 71 struct acpi_buffer input = { sizeof(input_val), &input_val }; 72 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; 73 union acpi_object *obj; 74 acpi_status status; 75 int code; 76 77 status = wmi_evaluate_method(LENOVO_YMC_QUERY_GUID, 78 LENOVO_YMC_QUERY_INSTANCE, 79 LENOVO_YMC_QUERY_METHOD, 80 &input, &output); 81 82 if (ACPI_FAILURE(status)) { 83 dev_warn(&wdev->dev, 84 "Failed to evaluate query method: %s\n", 85 acpi_format_exception(status)); 86 return; 87 } 88 89 obj = output.pointer; 90 91 if (obj->type != ACPI_TYPE_INTEGER) { 92 dev_warn(&wdev->dev, 93 "WMI event data is not an integer\n"); 94 goto free_obj; 95 } 96 code = obj->integer.value; 97 98 if (!sparse_keymap_report_event(priv->input_dev, code, 1, true)) 99 dev_warn(&wdev->dev, "Unknown key %d pressed\n", code); 100 101 free_obj: 102 kfree(obj); 103 lenovo_ymc_trigger_ec(wdev, priv); 104 } 105 106 static void acpi_dev_put_helper(void *p) { acpi_dev_put(p); } 107 108 static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx) 109 { 110 struct lenovo_ymc_private *priv; 111 struct input_dev *input_dev; 112 int err; 113 114 ec_trigger |= dmi_check_system(ec_trigger_quirk_dmi_table); 115 116 priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL); 117 if (!priv) 118 return -ENOMEM; 119 120 if (ec_trigger) { 121 pr_debug("Lenovo YMC enable EC triggering.\n"); 122 priv->ec_acpi_dev = acpi_dev_get_first_match_dev("VPC2004", NULL, -1); 123 124 if (!priv->ec_acpi_dev) { 125 dev_err(&wdev->dev, "Could not find EC ACPI device.\n"); 126 return -ENODEV; 127 } 128 err = devm_add_action_or_reset(&wdev->dev, 129 acpi_dev_put_helper, priv->ec_acpi_dev); 130 if (err) { 131 dev_err(&wdev->dev, 132 "Could not clean up EC ACPI device: %d\n", err); 133 return err; 134 } 135 } 136 137 input_dev = devm_input_allocate_device(&wdev->dev); 138 if (!input_dev) 139 return -ENOMEM; 140 141 input_dev->name = "Lenovo Yoga Tablet Mode Control switch"; 142 input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0"; 143 input_dev->id.bustype = BUS_HOST; 144 input_dev->dev.parent = &wdev->dev; 145 err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL); 146 if (err) { 147 dev_err(&wdev->dev, 148 "Could not set up input device keymap: %d\n", err); 149 return err; 150 } 151 152 err = input_register_device(input_dev); 153 if (err) { 154 dev_err(&wdev->dev, 155 "Could not register input device: %d\n", err); 156 return err; 157 } 158 159 priv->input_dev = input_dev; 160 dev_set_drvdata(&wdev->dev, priv); 161 162 /* Report the state for the first time on probe */ 163 lenovo_ymc_trigger_ec(wdev, priv); 164 lenovo_ymc_notify(wdev, NULL); 165 return 0; 166 } 167 168 static const struct wmi_device_id lenovo_ymc_wmi_id_table[] = { 169 { .guid_string = LENOVO_YMC_EVENT_GUID }, 170 { } 171 }; 172 MODULE_DEVICE_TABLE(wmi, lenovo_ymc_wmi_id_table); 173 174 static struct wmi_driver lenovo_ymc_driver = { 175 .driver = { 176 .name = "lenovo-ymc", 177 }, 178 .id_table = lenovo_ymc_wmi_id_table, 179 .probe = lenovo_ymc_probe, 180 .notify = lenovo_ymc_notify, 181 }; 182 183 module_wmi_driver(lenovo_ymc_driver); 184 185 MODULE_AUTHOR("Gergo Koteles <soyer@irl.hu>"); 186 MODULE_DESCRIPTION("Lenovo Yoga Mode Control driver"); 187 MODULE_LICENSE("GPL"); 188