Re: [PATCH v3 3/4] platform/x86: Add Lenovo Capability Data 01 WMI Driver

Derek J. Clark
2025-02-25T22:33:50Z

On February 25, 2025 1:59:54 PM PST, "Derek J. Clark" <derekjohn.clark@gmail.com> wrote:
>Adds lenovo-wmi-capdata01.c which provides a driver for the
>LENOVO_CAPABILITY_DATA_01 WMI data block that comes on "Other Mode"
>enabled hardware. Provides an interface for querying if a given
>attribute is supported by the hardware, as well as its default_value,
>max_value, min_value, and step increment.
>v3:
>- Add as component to lenovo-wmi-other driver.
>v2:
>- Use devm_kmalloc to ensure driver can be instanced, remove global
> reference.
>- Ensure reverse Christmas tree for all variable declarations.
>- Remove extra whitespace.
>- Use guard(mutex) in all mutex instances, global mutex.
>- Use pr_fmt instead of adding the driver name to each pr_err.
>- Remove noisy pr_info usage.
>- Rename capdata_wmi to lenovo_wmi_cd01_priv and cd01_wmi to priv.
>- Use list to get the lenovo_wmi_cd01_priv instance in
> lenovo_wmi_capdata01_get as none of the data provided by the macros
> that will use it can pass a member of the struct for use in
> container_of.
>
>Signed-off-by: Derek J. Clark <derekjohn.clark@gmail.com>
>---
> MAINTAINERS | 1 +
> drivers/platform/x86/Kconfig | 5 +
> drivers/platform/x86/Makefile | 1 +
> drivers/platform/x86/lenovo-wmi-capdata01.c | 140 ++++++++++++++++++++
> drivers/platform/x86/lenovo-wmi.h | 19 +++
> 5 files changed, 166 insertions(+)
> create mode 100644 drivers/platform/x86/lenovo-wmi-capdata01.c
>
>diff --git a/MAINTAINERS b/MAINTAINERS
>index cf7f4fce1a25..f6d3e79e50ce 100644
>--- a/MAINTAINERS
>+++ b/MAINTAINERS
>@@ -13157,6 +13157,7 @@ L: platform-driver-x86@vger.kernel.org
> S: Maintained
> F: Documentation/wmi/devices/lenovo-wmi-gamezone.rst
> F: Documentation/wmi/devices/lenovo-wmi-other.rst
>+F: drivers/platform/x86/lenovo-wmi-capdata01.c
> F: drivers/platform/x86/lenovo-wmi-gamezone.c
> F: drivers/platform/x86/lenovo-wmi.c
> F: drivers/platform/x86/lenovo-wmi.h
>diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
>index 875822e6bd65..56336dc3c2d0 100644
>--- a/drivers/platform/x86/Kconfig
>+++ b/drivers/platform/x86/Kconfig
>@@ -475,6 +475,11 @@ config LENOVO_WMI_GAMEZONE
> To compile this driver as a module, choose M here: the module will
> be called lenovo-wmi-gamezone.
>
>+config LENOVO_WMI_DATA01
>+ tristate
>+ depends on ACPI_WMI
>+ select LENOVO_WMI
>+
> config IDEAPAD_LAPTOP
> tristate "Lenovo IdeaPad Laptop Extras"
> depends on ACPI
>diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
>index 4a7b2d14eb82..be9031bea090 100644
>--- a/drivers/platform/x86/Makefile
>+++ b/drivers/platform/x86/Makefile
>@@ -70,6 +70,7 @@ obj-$(CONFIG_YT2_1380) += lenovo-yoga-tab2-pro-1380-fastcharger.o
> obj-$(CONFIG_LENOVO_WMI) += lenovo-wmi.o
> obj-$(CONFIG_LENOVO_WMI_CAMERA) += lenovo-wmi-camera.o
> obj-$(CONFIG_LENOVO_WMI_GAMEZONE) += lenovo-wmi-gamezone.o
>+obj-$(CONFIG_LENOVO_WMI_DATA01) += lenovo-wmi-capdata01.o
>
> # Intel
> obj-y += intel/
>diff --git a/drivers/platform/x86/lenovo-wmi-capdata01.c b/drivers/platform/x86/lenovo-wmi-capdata01.c
>new file mode 100644
>index 000000000000..0fe156d5d770
>--- /dev/null
>+++ b/drivers/platform/x86/lenovo-wmi-capdata01.c
>@@ -0,0 +1,140 @@
>+// SPDX-License-Identifier: GPL-2.0-or-later
>+/*
>+ * LENOVO_CAPABILITY_DATA_01 WMI data block driver. This interface provides
>+ * information on tunable attributes used by the "Other Mode" WMI interface,
>+ * including if it is supported by the hardware, the default_value, max_value,
>+ * min_value, and step increment.
>+ *
>+ * Copyright(C) 2024 Derek J. Clark <derekjohn.clark@gmail.com>
>+ */
>+
>+#include <linux/cleanup.h>
>+#include <linux/component.h>
>+#include <linux/container_of.h>
>+#include <linux/device.h>
>+#include <linux/gfp_types.h>
>+#include <linux/types.h>
>+#include <linux/wmi.h>
>+#include "lenovo-wmi.h"
>+
>+/* Interface GUIDs */
>+#define LENOVO_CAPABILITY_DATA_01_GUID "7A8F5407-CB67-4D6E-B547-39B3BE018154"
>+
>+static int lenovo_cd01_component_bind(struct device *cd01_dev,
>+ struct device *om_dev, void *data)
>+{
>+ struct lenovo_wmi_cd01 *cd01 = dev_get_drvdata(cd01_dev);
>+ struct lenovo_wmi_om *om = dev_get_drvdata(om_dev);
>+
>+ om->cd01 = cd01;
>+ return 0;
>+}
>+
>+static void lenovo_cd01_component_unbind(struct device *cd01_dev,
>+ struct device *om_dev, void *data)
>+
>+{
>+ struct wmi_device *om_wdev =
>+ container_of(om_dev, struct wmi_device, dev);
>+ struct lenovo_wmi_om *om =
>+ container_of(&om_wdev, struct lenovo_wmi_om, wdev);
>+
>+ om->cd01 = NULL;
>+}
>+
>+static const struct component_ops lenovo_cd01_component_ops = {
>+ .bind = lenovo_cd01_component_bind,
>+ .unbind = lenovo_cd01_component_unbind,
>+};
>+
>+static int lenovo_wmi_cd01_setup(struct lenovo_wmi_cd01 *cd01)
>+{
>+ size_t cd_size = sizeof(struct capdata01);
>+ int count, idx;
>+
>+ count = wmidev_instance_count(cd01->wdev);
>+
>+ cd01->capdata = devm_kmalloc_array(&cd01->wdev->dev, (size_t)count,
>+ sizeof(*cd01->capdata), GFP_KERNEL);
>+ if (!cd01->capdata)
>+ return -ENOMEM;
>+
>+ cd01->instance_count = count;
>+
>+ for (idx = 0; idx < count; idx++) {
>+ union acpi_object *ret_obj __free(kfree) = NULL;
>+ struct capdata01 *cap_ptr =
>+ devm_kmalloc(&cd01->wdev->dev, cd_size, GFP_KERNEL);
>+ ret_obj = wmidev_block_query(cd01->wdev, idx);
>+ if (!ret_obj)
>+ continue;
>+
>+ if (ret_obj->type != ACPI_TYPE_BUFFER)
>+ continue;
>+
>+ if (ret_obj->buffer.length != cd_size)
>+ continue;
>+
>+ memcpy(cap_ptr, ret_obj->buffer.pointer,
>+ ret_obj->buffer.length);
>+ cd01->capdata[idx] = cap_ptr;
>+ }
>+ return 0;
>+}
>+
>+static int lenovo_wmi_cd01_probe(struct wmi_device *wdev, const void *context)
>+
>+{
>+ struct lenovo_wmi_cd01 *cd01;
>+ int ret;
>+
>+ cd01 = devm_kzalloc(&wdev->dev, sizeof(*cd01), GFP_KERNEL);
>+ if (!cd01)
>+ return -ENOMEM;
>+
>+ cd01->wdev = wdev;
>+
>+ ret = lenovo_wmi_cd01_setup(cd01);
>+ if (ret)
>+ return ret;
>+
>+ dev_set_drvdata(&wdev->dev, cd01);
>+
>+ ret = component_add(&wdev->dev, &lenovo_cd01_component_ops);
>+
>+ return ret;
>+}
>+
>+static void lenovo_wmi_cd01_remove(struct wmi_device *wdev)
>+{
>+ component_del(&wdev->dev, &lenovo_cd01_component_ops);
>+}
>+
>+static const struct wmi_device_id lenovo_wmi_cd01_id_table[] = {
>+ { LENOVO_CAPABILITY_DATA_01_GUID, NULL },
>+ {}
>+};
>+
>+static struct wmi_driver lenovo_wmi_cd01_driver = {
>+ .driver = {
>+ .name = "lenovo_wmi_cd01",
>+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
>+ },
>+ .id_table = lenovo_wmi_cd01_id_table,
>+ .probe = lenovo_wmi_cd01_probe,
>+ .remove = lenovo_wmi_cd01_remove,
>+ .no_singleton = true,
>+};
>+
>+int lenovo_wmi_cd01_match(struct device *dev, void *data)
>+{
>+ return dev->driver == &lenovo_wmi_cd01_driver.driver;
>+}
>+EXPORT_SYMBOL_GPL(lenovo_wmi_cd01_match);
>+

This should have been an EXPORT_SYMBOL_NS_GPL in the CAPDATA_WMI namespace. I thought I changed it but must have dropped it by mistake. I will fix this next time.

- Derek

>+module_wmi_driver(lenovo_wmi_cd01_driver);
>+
>+MODULE_DEVICE_TABLE(wmi, lenovo_wmi_cd01_id_table);
>+MODULE_AUTHOR("Derek J. Clark <derekjohn.clark@gmail.com>");
>+MODULE_DESCRIPTION("Lenovo Capability Data 01 WMI Driver");
>+MODULE_LICENSE("GPL");
>diff --git a/drivers/platform/x86/lenovo-wmi.h b/drivers/platform/x86/lenovo-wmi.h
>index 113928b4fc0f..07fa67ed89d6 100644
>--- a/drivers/platform/x86/lenovo-wmi.h
>+++ b/drivers/platform/x86/lenovo-wmi.h
>@@ -45,6 +45,22 @@ enum lenovo_wmi_action {
> THERMAL_MODE_EVENT = 1,
> };
>
>+/* capdata01 structs */
>+struct lenovo_wmi_cd01 {
>+ struct capdata01 **capdata;
>+ struct wmi_device *wdev;
>+ int instance_count;
>+};
>+
>+struct capdata01 {
>+ u32 id;
>+ u32 supported;
>+ u32 default_value;
>+ u32 step;
>+ u32 min_value;
>+ u32 max_value;
>+};
>+
> /* wmidev_evaluate_method helper functions */
> int lenovo_wmidev_evaluate_method_2(struct wmi_device *wdev, u8 instance,
> u32 method_id, u32 arg0, u32 arg1,
>@@ -52,6 +68,9 @@ int lenovo_wmidev_evaluate_method_2(struct wmi_device *wdev, u8 instance,
> int lenovo_wmidev_evaluate_method_1(struct wmi_device *wdev, u8 instance,
> u32 method_id, u32 arg0, u32 *retval);
>
>+/* lenovo_wmi_cd01_driver match function */
>+int lenovo_wmi_cd01_match(struct device *dev, void *data);
>+
> /* lenovo_wmi_gz_driver notifier functions */
> int lenovo_wmi_gz_notifier_call(struct notifier_block *nb, unsigned long action,
> enum platform_profile_option *profile);

- Derek