diff options
Diffstat (limited to 'drivers/platform/x86/lenovo-ymc.c')
| -rw-r--r-- | drivers/platform/x86/lenovo-ymc.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/drivers/platform/x86/lenovo-ymc.c b/drivers/platform/x86/lenovo-ymc.c new file mode 100644 index 0000000000..e1fbc35504 --- /dev/null +++ b/drivers/platform/x86/lenovo-ymc.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * lenovo-ymc.c - Lenovo Yoga Mode Control driver + * + * Copyright © 2022 Gergo Koteles <soyer@irl.hu> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/acpi.h> +#include <linux/dmi.h> +#include <linux/input.h> +#include <linux/input/sparse-keymap.h> +#include <linux/wmi.h> +#include "ideapad-laptop.h" + +#define LENOVO_YMC_EVENT_GUID "06129D99-6083-4164-81AD-F092F9D773A6" +#define LENOVO_YMC_QUERY_GUID "09B0EE6E-C3FD-4243-8DA1-7911FF80BB8C" + +#define LENOVO_YMC_QUERY_INSTANCE 0 +#define LENOVO_YMC_QUERY_METHOD 0x01 + +static bool ec_trigger __read_mostly; +module_param(ec_trigger, bool, 0444); +MODULE_PARM_DESC(ec_trigger, "Enable EC triggering work-around to force emitting tablet mode events"); + +static bool force; +module_param(force, bool, 0444); +MODULE_PARM_DESC(force, "Force loading on boards without a convertible DMI chassis-type"); + +static const struct dmi_system_id ec_trigger_quirk_dmi_table[] = { + { + /* Lenovo Yoga 7 14ARB7 */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "82QF"), + }, + }, + { + /* Lenovo Yoga 7 14ACN6 */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), + DMI_MATCH(DMI_PRODUCT_NAME, "82N7"), + }, + }, + { } +}; + +static const struct dmi_system_id allowed_chasis_types_dmi_table[] = { + { + .matches = { + DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "31" /* Convertible */), + }, + }, + { + .matches = { + DMI_EXACT_MATCH(DMI_CHASSIS_TYPE, "32" /* Detachable */), + }, + }, + { } +}; + +struct lenovo_ymc_private { + struct input_dev *input_dev; + struct acpi_device *ec_acpi_dev; +}; + +static void lenovo_ymc_trigger_ec(struct wmi_device *wdev, struct lenovo_ymc_private *priv) +{ + int err; + + if (!priv->ec_acpi_dev) + return; + + err = write_ec_cmd(priv->ec_acpi_dev->handle, VPCCMD_W_YMC, 1); + if (err) + dev_warn(&wdev->dev, "Could not write YMC: %d\n", err); +} + +static const struct key_entry lenovo_ymc_keymap[] = { + /* Laptop */ + { KE_SW, 0x01, { .sw = { SW_TABLET_MODE, 0 } } }, + /* Tablet */ + { KE_SW, 0x02, { .sw = { SW_TABLET_MODE, 1 } } }, + /* Drawing Board */ + { KE_SW, 0x03, { .sw = { SW_TABLET_MODE, 1 } } }, + /* Tent */ + { KE_SW, 0x04, { .sw = { SW_TABLET_MODE, 1 } } }, + { KE_END }, +}; + +static void lenovo_ymc_notify(struct wmi_device *wdev, union acpi_object *data) +{ + struct lenovo_ymc_private *priv = dev_get_drvdata(&wdev->dev); + u32 input_val = 0; + struct acpi_buffer input = { sizeof(input_val), &input_val }; + struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *obj; + acpi_status status; + int code; + + status = wmi_evaluate_method(LENOVO_YMC_QUERY_GUID, + LENOVO_YMC_QUERY_INSTANCE, + LENOVO_YMC_QUERY_METHOD, + &input, &output); + + if (ACPI_FAILURE(status)) { + dev_warn(&wdev->dev, + "Failed to evaluate query method: %s\n", + acpi_format_exception(status)); + return; + } + + obj = output.pointer; + + if (obj->type != ACPI_TYPE_INTEGER) { + dev_warn(&wdev->dev, + "WMI event data is not an integer\n"); + goto free_obj; + } + code = obj->integer.value; + + if (!sparse_keymap_report_event(priv->input_dev, code, 1, true)) + dev_warn(&wdev->dev, "Unknown key %d pressed\n", code); + +free_obj: + kfree(obj); + lenovo_ymc_trigger_ec(wdev, priv); +} + +static void acpi_dev_put_helper(void *p) { acpi_dev_put(p); } + +static int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx) +{ + struct lenovo_ymc_private *priv; + struct input_dev *input_dev; + int err; + + if (!dmi_check_system(allowed_chasis_types_dmi_table)) { + if (force) + dev_info(&wdev->dev, "Force loading Lenovo YMC support\n"); + else + return -ENODEV; + } + + ec_trigger |= dmi_check_system(ec_trigger_quirk_dmi_table); + + priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + if (ec_trigger) { + pr_debug("Lenovo YMC enable EC triggering.\n"); + priv->ec_acpi_dev = acpi_dev_get_first_match_dev("VPC2004", NULL, -1); + + if (!priv->ec_acpi_dev) { + dev_err(&wdev->dev, "Could not find EC ACPI device.\n"); + return -ENODEV; + } + err = devm_add_action_or_reset(&wdev->dev, + acpi_dev_put_helper, priv->ec_acpi_dev); + if (err) { + dev_err(&wdev->dev, + "Could not clean up EC ACPI device: %d\n", err); + return err; + } + } + + input_dev = devm_input_allocate_device(&wdev->dev); + if (!input_dev) + return -ENOMEM; + + input_dev->name = "Lenovo Yoga Tablet Mode Control switch"; + input_dev->phys = LENOVO_YMC_EVENT_GUID "/input0"; + input_dev->id.bustype = BUS_HOST; + input_dev->dev.parent = &wdev->dev; + err = sparse_keymap_setup(input_dev, lenovo_ymc_keymap, NULL); + if (err) { + dev_err(&wdev->dev, + "Could not set up input device keymap: %d\n", err); + return err; + } + + err = input_register_device(input_dev); + if (err) { + dev_err(&wdev->dev, + "Could not register input device: %d\n", err); + return err; + } + + priv->input_dev = input_dev; + dev_set_drvdata(&wdev->dev, priv); + + /* Report the state for the first time on probe */ + lenovo_ymc_trigger_ec(wdev, priv); + lenovo_ymc_notify(wdev, NULL); + return 0; +} + +static const struct wmi_device_id lenovo_ymc_wmi_id_table[] = { + { .guid_string = LENOVO_YMC_EVENT_GUID }, + { } +}; +MODULE_DEVICE_TABLE(wmi, lenovo_ymc_wmi_id_table); + +static struct wmi_driver lenovo_ymc_driver = { + .driver = { + .name = "lenovo-ymc", + }, + .id_table = lenovo_ymc_wmi_id_table, + .probe = lenovo_ymc_probe, + .notify = lenovo_ymc_notify, +}; + +module_wmi_driver(lenovo_ymc_driver); + +MODULE_AUTHOR("Gergo Koteles <soyer@irl.hu>"); +MODULE_DESCRIPTION("Lenovo Yoga Mode Control driver"); +MODULE_LICENSE("GPL"); |