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 bool force; 28 module_param(force, bool, 0444); 29 MODULE_PARM_DESC(force, "Force loading on boards without a convertible DMI chassis-type"); 30 31 static const struct dmi_system_id ec_trigger_quirk_dmi_table[] = { 32 { 33 /* Lenovo Yoga 7 14ARB7 */ 34 .matches = { 35 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 36 DMI_MATCH(DMI_PRODUCT_NAME, "82QF"), 37 }, 38 }, 39 { 40 /* Lenovo Yoga 7 14ACN6 */ 41 .matches = { 42 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 43 DMI_MATCH(DMI_PRODUCT_NAME, "82N7"), 44 }, 45 }, 46 { } 47 }; 48 49 static const struct dmi_system_id allowed_chasis_types_dmi_table[] = { 50 { 51 .matches = { 52 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */), 53 }, 54 }, 55 { 56 .matches = { 57 DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */), 58 }, 59 }, 60 { } 61 }; 62 63 struct lenovo_ymc_private { 64 struct input_dev *input_dev; 65 struct acpi_device *ec_acpi_dev; 66 }; 67 68 static void lenovo_ymc_trigger_ec(struct wmi_device *wdev, struct lenovo_ymc_private *priv) 69 { 70 int err; 71 72 if (!priv->ec_acpi_dev) 73 return; 74 75 err = write_ec_cmd(priv->ec_acpi_dev->handle, VPCCMD_W_YMC, 1); 76 if (err) 77 dev_warn(&wdev->dev, "Could not write YMC: %d\n", err); 78 } 79 80 static const struct key_entry lenovo_ymc_keymap[] = { 81 /* Laptop */ 82 { KE_SW, 0x01, { .sw = { SW_TABLET_MODE, 0 } } }, 83 /* Tablet */ 84 { KE_SW, 0x02, { .sw = { SW_TABLET_MODE, 1 } } }, 85 /* Drawing Board */ 86 { KE_SW, 0x03, { .sw = { SW_TABLET_MODE, 1 } } }, 87 /* Tent */ 88 { KE_SW, 0x04, { .sw = { SW_TABLET_MODE, 1 } } }, 89 { KE_END }, 90 }; 91 92 static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data) 93 { 94 struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev); 95 u32 input_val = 0; 96 struct acpi_buffer input = { sizeof(input_val), &input_val }; 97 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; 98 union acpi_object *obj; 99 acpi_status status; 100 int code; 101 102 status = wmi_evaluate_method(LENOVO_YMC_QUERY_GUID, 103 LENOVO_YMC_QUERY_INSTANCE, 104 LENOVO_YMC_QUERY_METHOD, 105 &input, &output); 106 107 if (ACPI_FAILURE(status)) { 108 dev_warn(&wdev->dev, 109 "Failed to evaluate query method: %s\n", 110 acpi_format_exception(status)); 111 return; 112 } 113 114 obj = output.pointer; 115 116 if (obj->type != ACPI_TYPE_INTEGER) { 117 dev_warn(&wdev->dev, 118 "WMI event data is not an integer\n"); 119 goto free_obj; 120 } 121 code = obj->integer.value; 122 123 if (!sparse_keymap_report_event(priv->input_dev, code, 1, true)) 124 dev_warn(&wdev->dev, "Unknown key %d pressed\n", code); 125 126 free_obj: 127 kfree(obj); 128 lenovo_ymc_trigger_ec(wdev, priv); 129 } 130 131 static void acpi_dev_put_helper(void *p) { acpi_dev_put(p); } 132 133 static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx) 134 { 135 struct lenovo_ymc_private *priv; 136 struct input_dev *input_dev; 137 int err; 138 139 if (!dmi_check_system(allowed_chasis_types_dmi_table)) { 140 if (force) 141 dev_info(&wdev->dev, "Force loading Lenovo YMC support\n"); 142 else 143 return -ENODEV; 144 } 145 146 ec_trigger |= dmi_check_system(ec_trigger_quirk_dmi_table); 147 148 priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL); 149 if (!priv) 150 return -ENOMEM; 151 152 if (ec_trigger) { 153 pr_debug("Lenovo YMC enable EC triggering.\n"); 154 priv->ec_acpi_dev = acpi_dev_get_first_match_dev("VPC2004", NULL, -1); 155 156 if (!priv->ec_acpi_dev) { 157 dev_err(&wdev->dev, "Could not find EC ACPI device.\n"); 158 return -ENODEV; 159 } 160 err = devm_add_action_or_reset(&wdev->dev, 161 acpi_dev_put_helper, priv->ec_acpi_dev); 162 if (err) { 163 dev_err(&wdev->dev, 164 "Could not clean up EC ACPI device: %d\n", err); 165 return err; 166 } 167 } 168 169 input_dev = devm_input_allocate_device(&wdev->dev); 170 if (!input_dev) 171 return -ENOMEM; 172 173 input_dev->name = "Lenovo Yoga Tablet Mode Control switch"; 174 input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0"; 175 input_dev->id.bustype = BUS_HOST; 176 input_dev->dev.parent = &wdev->dev; 177 err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL); 178 if (err) { 179 dev_err(&wdev->dev, 180 "Could not set up input device keymap: %d\n", err); 181 return err; 182 } 183 184 err = input_register_device(input_dev); 185 if (err) { 186 dev_err(&wdev->dev, 187 "Could not register input device: %d\n", err); 188 return err; 189 } 190 191 priv->input_dev = input_dev; 192 dev_set_drvdata(&wdev->dev, priv); 193 194 /* Report the state for the first time on probe */ 195 lenovo_ymc_trigger_ec(wdev, priv); 196 lenovo_ymc_notify(wdev, NULL); 197 return 0; 198 } 199 200 static const struct wmi_device_id lenovo_ymc_wmi_id_table[] = { 201 { .guid_string = LENOVO_YMC_EVENT_GUID }, 202 { } 203 }; 204 MODULE_DEVICE_TABLE(wmi, lenovo_ymc_wmi_id_table); 205 206 static struct wmi_driver lenovo_ymc_driver = { 207 .driver = { 208 .name = "lenovo-ymc", 209 }, 210 .id_table = lenovo_ymc_wmi_id_table, 211 .probe = lenovo_ymc_probe, 212 .notify = lenovo_ymc_notify, 213 }; 214 215 module_wmi_driver(lenovo_ymc_driver); 216 217 MODULE_AUTHOR("Gergo Koteles <soyer@irl.hu>"); 218 MODULE_DESCRIPTION("Lenovo Yoga Mode Control driver"); 219 MODULE_LICENSE("GPL"); 220