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

["Derek J. Clark" <derekjohn.clark@gmail.com>]

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