This WMI driver for the tablet mode control switch for Lenovo Yoga
notebooks was originally written by Gergo Koteles. The mode is mapped to
a SW_TABLET_MODE switch capable input device.
I (Andrew) followed the suggestions that were posted in reply to Gergo's
RFC patch to follow-up and get it merged. Additionally I merged the
lenovo_ymc_trigger_ec function with the ideapad_trigger_ymc_next_read
function since it was no longer external. I have also added the word
"Tablet" to the driver description to hopefully make it more clear.
As Gergo said: It should work with models like the Yoga C940, Ideapad
flex 14API, Yoga 9 14IAP7, Yoga 7 14ARB7.
The 14ARB7 model must trigger the EC to send mode change events. This
might be a firmware bug.
I have additionally tested this on the Yoga 7 14IAL7.
Link: https://lore.kernel.org/r/20221004214332.35934-1-soyer@xxxxxx/
Co-developed-by: Andrew Kallmeyer <kallmeyeras@xxxxxxxxx>
Signed-off-by: Andrew Kallmeyer <kallmeyeras@xxxxxxxxx>
---
drivers/platform/x86/Kconfig | 10 ++
drivers/platform/x86/Makefile | 1 +
drivers/platform/x86/ideapad-laptop.h | 1 +
drivers/platform/x86/lenovo-ymc.c | 177 ++++++++++++++++++++++++++
4 files changed, 189 insertions(+)
create mode 100644 drivers/platform/x86/lenovo-ymc.c
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 5692385e2..858be0c65 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -470,6 +470,16 @@ config IDEAPAD_LAPTOP
This is a driver for Lenovo IdeaPad netbooks contains drivers for
rfkill switch, hotkey, fan control and backlight control.
+config LENOVO_YMC
+ tristate "Lenovo Yoga Tablet Mode Control"
+ depends on ACPI_WMI
+ depends on INPUT
+ depends on IDEAPAD_LAPTOP
+ select INPUT_SPARSEKMAP
+ help
+ This driver maps the Tablet Mode Control switch to SW_TABLET_MODE input
+ events for Lenovo Yoga notebooks.
+
config SENSORS_HDAPS
tristate "Thinkpad Hard Drive Active Protection System (hdaps)"
depends on INPUT
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 1d3d1b025..10054cdea 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_UV_SYSFS) += uv_sysfs.o
# IBM Thinkpad and Lenovo
obj-$(CONFIG_IBM_RTL) += ibm_rtl.o
obj-$(CONFIG_IDEAPAD_LAPTOP) += ideapad-laptop.o
+obj-$(CONFIG_LENOVO_YMC) += lenovo-ymc.o
obj-$(CONFIG_SENSORS_HDAPS) += hdaps.o
obj-$(CONFIG_THINKPAD_ACPI) += thinkpad_acpi.o
obj-$(CONFIG_THINKPAD_LMI) += think-lmi.o
diff --git a/drivers/platform/x86/ideapad-laptop.h b/drivers/platform/x86/ideapad-laptop.h
index 7dd8ce027..2564cb1cd 100644
--- a/drivers/platform/x86/ideapad-laptop.h
+++ b/drivers/platform/x86/ideapad-laptop.h
@@ -35,6 +35,7 @@ enum {
VPCCMD_W_FAN,
VPCCMD_R_RF,
VPCCMD_W_RF,
+ VPCCMD_W_YMC = 0x2A,
VPCCMD_R_FAN = 0x2B,
VPCCMD_R_SPECIAL_BUTTONS = 0x31,
VPCCMD_W_BL_POWER = 0x33,
diff --git a/drivers/platform/x86/lenovo-ymc.c b/drivers/platform/x86/lenovo-ymc.c
new file mode 100644
index 000000000..e29ada1b4
--- /dev/null
+++ b/drivers/platform/x86/lenovo-ymc.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * lenovo-ymc.c - Lenovo Yoga Mode Control driver
+ *
+ * Copyright © 2022 Gergo Koteles <soyer@xxxxxx>
+ */
+
+#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 0xAB
+
+static bool ec_trigger __read_mostly;
+module_param(ec_trigger, bool, 0644);
+MODULE_PARM_DESC(ec_trigger, "Enable EC triggering to emit YMC events");
+
+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"),
+ },
+ },
+ { },
+};
+
+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 (!ec_trigger || !priv || !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};
+ acpi_status status;
+ union acpi_object *obj;
+ 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 int lenovo_ymc_probe(struct wmi_device *wdev, const void *ctx)
+{
+ struct input_dev *input_dev;
+ struct lenovo_ymc_private *priv;
+ int err;
+
+ 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("VCP2004", NULL, -1);
+ if (!priv->ec_acpi_dev) {
+ dev_err(&wdev->dev, "Could not find EC ACPI device.\n");
+ return -ENODEV;
+ }
+ }
+
+ 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;
+
+ input_set_capability(input_dev, EV_SW, SW_TABLET_MODE);
+
+ 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);
+ lenovo_ymc_trigger_ec(wdev, priv);
+ 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@xxxxxx>");
+MODULE_DESCRIPTION("Lenovo Yoga Mode Control driver");
+MODULE_LICENSE("GPL");
