Add support for LENOVO_FAN_TEST_DATA WMI data block. Provides an
interface for querying the min/max fan speed RPM (reference data) of a
given fan ID.
Signed-off-by: Rong Zhang <i@rong.moe>
---
Changes in v2:
- Reword documentation
---
.../wmi/devices/lenovo-wmi-other.rst | 17 +++
drivers/platform/x86/lenovo/wmi-capdata.c | 102 ++++++++++++++++++
drivers/platform/x86/lenovo/wmi-capdata.h | 8 ++
3 files changed, 127 insertions(+)
diff --git a/Documentation/wmi/devices/lenovo-wmi-other.rst b/Documentation/wmi/devices/lenovo-wmi-other.rst
index fcad595d49af2..821282e07d93c 100644
--- a/Documentation/wmi/devices/lenovo-wmi-other.rst
+++ b/Documentation/wmi/devices/lenovo-wmi-other.rst
@@ -62,6 +62,13 @@ The following firmware-attributes are implemented:
- ppt_pl2_sppt: Platform Profile Tracking Slow Package Power Tracking
- ppt_pl3_fppt: Platform Profile Tracking Fast Package Power Tracking
+LENOVO_FAN_TEST_DATA
+-------------------------
+
+WMI GUID ``B642801B-3D21-45DE-90AE-6E86F164FB21``
+
+The LENOVO_FAN_TEST_DATA interface provides reference data for self-test of
+cooling fans.
WMI interface description
=========================
@@ -115,3 +122,13 @@ data using the `bmfdec <https://github.com/pali/bmfdec>`_ utility:
[WmiDataId(3), read, Description("Data Size.")] uint32 DataSize;
[WmiDataId(4), read, Description("Default Value"), WmiSizeIs("DataSize")] uint8 DefaultValue[];
};
+
+ [WMI, Dynamic, Provider("WmiProv"), Locale("MS\\0x409"), Description("Definition of Fan Test Data"), guid("{B642801B-3D21-45DE-90AE-6E86F164FB21}")]
+ class LENOVO_FAN_TEST_DATA {
+ [key, read] string InstanceName;
+ [read] boolean Active;
+ [WmiDataId(1), read, Description("Mode.")] uint32 NumOfFans;
+ [WmiDataId(2), read, Description("Fan ID."), WmiSizeIs("NumOfFans")] uint32 FanId[];
+ [WmiDataId(3), read, Description("Maximum Fan Speed."), WmiSizeIs("NumOfFans")] uint32 FanMaxSpeed[];
+ [WmiDataId(4), read, Description("Minumum Fan Speed."), WmiSizeIs("NumOfFans")] uint32 FanMinSpeed[];
+ };
diff --git a/drivers/platform/x86/lenovo/wmi-capdata.c b/drivers/platform/x86/lenovo/wmi-capdata.c
index e8ec30701d883..e456aace87f24 100644
--- a/drivers/platform/x86/lenovo/wmi-capdata.c
+++ b/drivers/platform/x86/lenovo/wmi-capdata.c
@@ -13,6 +13,10 @@
* attribute has multiple pages, one for each of the thermal modes managed by
* the Gamezone interface.
*
+ * Fan Test Data includes the max/min fan speed RPM for each fan. This is
+ * reference data for self-test. If the fan is in good condition, it is capable
+ * to spin faster than max RPM or slower than min RPM.
+ *
* Copyright (C) 2025 Derek J. Clark <derekjohn.clark@gmail.com>
* - Initial implementation (formerly named lenovo-wmi-capdata01)
*
@@ -41,6 +45,7 @@
#define LENOVO_CAPABILITY_DATA_00_GUID "362A3AFE-3D96-4665-8530-96DAD5BB300E"
#define LENOVO_CAPABILITY_DATA_01_GUID "7A8F5407-CB67-4D6E-B547-39B3BE018154"
+#define LENOVO_FAN_TEST_DATA_GUID "B642801B-3D21-45DE-90AE-6E86F164FB21"
#define ACPI_AC_CLASS "ac_adapter"
#define ACPI_AC_NOTIFY_STATUS 0x80
@@ -48,6 +53,7 @@
enum lwmi_cd_type {
LENOVO_CAPABILITY_DATA_00,
LENOVO_CAPABILITY_DATA_01,
+ LENOVO_FAN_TEST_DATA,
};
#define LWMI_CD_TABLE_ITEM(_type) \
@@ -64,6 +70,7 @@ static const struct lwmi_cd_info {
} lwmi_cd_table[] = {
LWMI_CD_TABLE_ITEM(LENOVO_CAPABILITY_DATA_00),
LWMI_CD_TABLE_ITEM(LENOVO_CAPABILITY_DATA_01),
+ LWMI_CD_TABLE_ITEM(LENOVO_FAN_TEST_DATA),
};
struct lwmi_cd_priv {
@@ -80,6 +87,7 @@ struct cd_list {
union {
DECLARE_FLEX_ARRAY(struct capdata00, cd00);
DECLARE_FLEX_ARRAY(struct capdata01, cd01);
+ DECLARE_FLEX_ARRAY(struct capdata_fan, cd_fan);
};
};
@@ -108,6 +116,14 @@ static int lwmi_cd_component_bind(struct device *cd_dev,
case LENOVO_CAPABILITY_DATA_01:
binder->cd01_list = priv->list;
break;
+ case LENOVO_FAN_TEST_DATA:
+ /*
+ * Do not expose dummy data.
+ * See also lwmi_cd_fan_list_alloc_cache().
+ */
+ if (priv->list->count)
+ binder->cd_fan_list = priv->list;
+ break;
default:
return -EINVAL;
}
@@ -152,6 +168,9 @@ EXPORT_SYMBOL_NS_GPL(lwmi_cd00_get_data, "LENOVO_WMI_CD");
DEF_LWMI_CDXX_GET_DATA(cd01, LENOVO_CAPABILITY_DATA_01, struct capdata01);
EXPORT_SYMBOL_NS_GPL(lwmi_cd01_get_data, "LENOVO_WMI_CD");
+DEF_LWMI_CDXX_GET_DATA(cd_fan, LENOVO_FAN_TEST_DATA, struct capdata_fan);
+EXPORT_SYMBOL_NS_GPL(lwmi_cd_fan_get_data, "LENOVO_WMI_CD");
+
/**
* lwmi_cd_cache() - Cache all WMI data block information
* @priv: lenovo-wmi-capdata driver data.
@@ -175,6 +194,9 @@ static int lwmi_cd_cache(struct lwmi_cd_priv *priv)
p = &priv->list->cd01[0];
size = sizeof(priv->list->cd01[0]);
break;
+ case LENOVO_FAN_TEST_DATA:
+ /* Done by lwmi_cd_alloc() => lwmi_cd_fan_list_alloc_cache(). */
+ return 0;
default:
return -EINVAL;
}
@@ -197,6 +219,78 @@ static int lwmi_cd_cache(struct lwmi_cd_priv *priv)
return 0;
}
+/**
+ * lwmi_cd_fan_list_alloc_cache() - Alloc and cache Fan Test Data list
+ * @priv: lenovo-wmi-capdata driver data.
+ * @listptr: Pointer to returned cd_list pointer.
+ *
+ * Return: count of fans found, or an error.
+ */
+static int lwmi_cd_fan_list_alloc_cache(struct lwmi_cd_priv *priv, struct cd_list **listptr)
+{
+ u32 count, *fan_ids, *fan_min_rpms, *fan_max_rpms;
+ union acpi_object *ret_obj __free(kfree) = NULL;
+ struct block { u32 nr; u32 data[]; } *block;
+ struct cd_list *list;
+ size_t size;
+ int idx;
+
+ ret_obj = wmidev_block_query(priv->wdev, 0);
+ if (!ret_obj)
+ return -ENODEV;
+
+ /*
+ * This is usually caused by a dummy ACPI method. Do not return an error
+ * as failing to probe this device will result in master driver being
+ * unbound - this behavior aligns with lwmi_cd_cache().
+ */
+ if (ret_obj->type != ACPI_TYPE_BUFFER) {
+ count = 0;
+ goto alloc;
+ }
+
+ size = ret_obj->buffer.length;
+ block = (struct block *)ret_obj->buffer.pointer;
+
+ count = size >= sizeof(*block) ? block->nr : 0;
+ if (size < struct_size(block, data, count * 3)) {
+ dev_warn(&priv->wdev->dev,
+ "incomplete fan test data block: %zu < %zu, ignoring\n",
+ size, struct_size(block, data, count * 3));
+ count = 0;
+ }
+
+ if (count == 0)
+ goto alloc;
+
+ if (count > U8_MAX) {
+ dev_warn(&priv->wdev->dev,
+ "too many fans reported: %u > %u, truncating\n",
+ count, U8_MAX);
+ count = U8_MAX;
+ }
+
+ fan_ids = &block->data[0];
+ fan_max_rpms = &block->data[count];
+ fan_min_rpms = &block->data[count * 2];
+
+alloc:
+ list = devm_kzalloc(&priv->wdev->dev, struct_size(list, cd_fan, count), GFP_KERNEL);
+ if (!list)
+ return -ENOMEM;
+
+ for (idx = 0; idx < count; idx++) {
+ list->cd_fan[idx] = (struct capdata_fan) {
+ .id = fan_ids[idx],
+ .min_rpm = fan_min_rpms[idx],
+ .max_rpm = fan_max_rpms[idx],
+ };
+ }
+
+ *listptr = list;
+ return count;
+}
+
/**
* lwmi_cd_alloc() - Allocate a cd_list struct in drvdata
* @priv: lenovo-wmi-capdata driver data.
@@ -222,6 +316,12 @@ static int lwmi_cd_alloc(struct lwmi_cd_priv *priv, enum lwmi_cd_type type)
case LENOVO_CAPABILITY_DATA_01:
list_size = struct_size(list, cd01, count);
break;
+ case LENOVO_FAN_TEST_DATA:
+ count = lwmi_cd_fan_list_alloc_cache(priv, &list);
+ if (count < 0)
+ return count;
+
+ goto got_list;
default:
return -EINVAL;
}
@@ -230,6 +330,7 @@ static int lwmi_cd_alloc(struct lwmi_cd_priv *priv, enum lwmi_cd_type type)
if (!list)
return -ENOMEM;
+got_list:
ret = devm_mutex_init(&priv->wdev->dev, &list->list_mutex);
if (ret)
return ret;
@@ -368,6 +469,7 @@ static void lwmi_cd_remove(struct wmi_device *wdev)
static const struct wmi_device_id lwmi_cd_id_table[] = {
{ LWMI_CD_WDEV_ID(LENOVO_CAPABILITY_DATA_00) },
{ LWMI_CD_WDEV_ID(LENOVO_CAPABILITY_DATA_01) },
+ { LWMI_CD_WDEV_ID(LENOVO_FAN_TEST_DATA) },
{}
};
diff --git a/drivers/platform/x86/lenovo/wmi-capdata.h b/drivers/platform/x86/lenovo/wmi-capdata.h
index a6f0cb006e745..52bc215ac43d8 100644
--- a/drivers/platform/x86/lenovo/wmi-capdata.h
+++ b/drivers/platform/x86/lenovo/wmi-capdata.h
@@ -26,13 +26,21 @@ struct capdata01 {
u32 max_value;
};
+struct capdata_fan {
+ u32 id;
+ u32 min_rpm;
+ u32 max_rpm;
+};
+
struct lwmi_cd_binder {
struct cd_list *cd00_list;
struct cd_list *cd01_list;
+ struct cd_list *cd_fan_list;
};
int lwmi_cd00_get_data(struct cd_list *list, u32 attribute_id, struct capdata00 *output);
int lwmi_cd01_get_data(struct cd_list *list, u32 attribute_id, struct capdata01 *output);
+int lwmi_cd_fan_get_data(struct cd_list *list, u32 attribute_id, struct capdata_fan *output);
void lwmi_cd_match_add_all(struct device *master, struct component_match **matchptr);
#endif /* !_LENOVO_WMI_CAPDATA_H_ */
--
2.51.0On Thu, Oct 30, 2025 at 12:40 PM Rong Zhang <i@rong.moe> wrote:
>
> Add support for LENOVO_FAN_TEST_DATA WMI data block. Provides an
> interface for querying the min/max fan speed RPM (reference data) of a
> given fan ID.
>
> Signed-off-by: Rong Zhang <i@rong.moe>
> ---
> Changes in v2:
> - Reword documentation
> ---
> .../wmi/devices/lenovo-wmi-other.rst | 17 +++
> drivers/platform/x86/lenovo/wmi-capdata.c | 102 ++++++++++++++++++
> drivers/platform/x86/lenovo/wmi-capdata.h | 8 ++
> 3 files changed, 127 insertions(+)
>
> diff --git a/Documentation/wmi/devices/lenovo-wmi-other.rst b/Documentation/wmi/devices/lenovo-wmi-other.rst
> index fcad595d49af2..821282e07d93c 100644
> --- a/Documentation/wmi/devices/lenovo-wmi-other.rst
> +++ b/Documentation/wmi/devices/lenovo-wmi-other.rst
> @@ -62,6 +62,13 @@ The following firmware-attributes are implemented:
> - ppt_pl2_sppt: Platform Profile Tracking Slow Package Power Tracking
> - ppt_pl3_fppt: Platform Profile Tracking Fast Package Power Tracking
>
> +LENOVO_FAN_TEST_DATA
> +-------------------------
> +
> +WMI GUID ``B642801B-3D21-45DE-90AE-6E86F164FB21``
> +
> +The LENOVO_FAN_TEST_DATA interface provides reference data for self-test of
> +cooling fans.
>
> WMI interface description
> =========================
> @@ -115,3 +122,13 @@ data using the `bmfdec <https://github.com/pali/bmfdec>`_ utility:
> [WmiDataId(3), read, Description("Data Size.")] uint32 DataSize;
> [WmiDataId(4), read, Description("Default Value"), WmiSizeIs("DataSize")] uint8 DefaultValue[];
> };
> +
> + [WMI, Dynamic, Provider("WmiProv"), Locale("MS\\0x409"), Description("Definition of Fan Test Data"), guid("{B642801B-3D21-45DE-90AE-6E86F164FB21}")]
> + class LENOVO_FAN_TEST_DATA {
> + [key, read] string InstanceName;
> + [read] boolean Active;
> + [WmiDataId(1), read, Description("Mode.")] uint32 NumOfFans;
> + [WmiDataId(2), read, Description("Fan ID."), WmiSizeIs("NumOfFans")] uint32 FanId[];
> + [WmiDataId(3), read, Description("Maximum Fan Speed."), WmiSizeIs("NumOfFans")] uint32 FanMaxSpeed[];
> + [WmiDataId(4), read, Description("Minumum Fan Speed."), WmiSizeIs("NumOfFans")] uint32 FanMinSpeed[];
> + };
> diff --git a/drivers/platform/x86/lenovo/wmi-capdata.c b/drivers/platform/x86/lenovo/wmi-capdata.c
> index e8ec30701d883..e456aace87f24 100644
> --- a/drivers/platform/x86/lenovo/wmi-capdata.c
> +++ b/drivers/platform/x86/lenovo/wmi-capdata.c
> @@ -13,6 +13,10 @@
> * attribute has multiple pages, one for each of the thermal modes managed by
> * the Gamezone interface.
> *
> + * Fan Test Data includes the max/min fan speed RPM for each fan. This is
> + * reference data for self-test. If the fan is in good condition, it is capable
> + * to spin faster than max RPM or slower than min RPM.
> + *
> * Copyright (C) 2025 Derek J. Clark <derekjohn.clark@gmail.com>
> * - Initial implementation (formerly named lenovo-wmi-capdata01)
> *
> @@ -41,6 +45,7 @@
>
> #define LENOVO_CAPABILITY_DATA_00_GUID "362A3AFE-3D96-4665-8530-96DAD5BB300E"
> #define LENOVO_CAPABILITY_DATA_01_GUID "7A8F5407-CB67-4D6E-B547-39B3BE018154"
> +#define LENOVO_FAN_TEST_DATA_GUID "B642801B-3D21-45DE-90AE-6E86F164FB21"
>
> #define ACPI_AC_CLASS "ac_adapter"
> #define ACPI_AC_NOTIFY_STATUS 0x80
> @@ -48,6 +53,7 @@
> enum lwmi_cd_type {
> LENOVO_CAPABILITY_DATA_00,
> LENOVO_CAPABILITY_DATA_01,
> + LENOVO_FAN_TEST_DATA,
> };
>
> #define LWMI_CD_TABLE_ITEM(_type) \
> @@ -64,6 +70,7 @@ static const struct lwmi_cd_info {
> } lwmi_cd_table[] = {
> LWMI_CD_TABLE_ITEM(LENOVO_CAPABILITY_DATA_00),
> LWMI_CD_TABLE_ITEM(LENOVO_CAPABILITY_DATA_01),
> + LWMI_CD_TABLE_ITEM(LENOVO_FAN_TEST_DATA),
> };
>
> struct lwmi_cd_priv {
> @@ -80,6 +87,7 @@ struct cd_list {
> union {
> DECLARE_FLEX_ARRAY(struct capdata00, cd00);
> DECLARE_FLEX_ARRAY(struct capdata01, cd01);
> + DECLARE_FLEX_ARRAY(struct capdata_fan, cd_fan);
> };
> };
>
> @@ -108,6 +116,14 @@ static int lwmi_cd_component_bind(struct device *cd_dev,
> case LENOVO_CAPABILITY_DATA_01:
> binder->cd01_list = priv->list;
> break;
> + case LENOVO_FAN_TEST_DATA:
> + /*
> + * Do not expose dummy data.
> + * See also lwmi_cd_fan_list_alloc_cache().
> + */
> + if (priv->list->count)
> + binder->cd_fan_list = priv->list;
> + break;
> default:
> return -EINVAL;
> }
> @@ -152,6 +168,9 @@ EXPORT_SYMBOL_NS_GPL(lwmi_cd00_get_data, "LENOVO_WMI_CD");
> DEF_LWMI_CDXX_GET_DATA(cd01, LENOVO_CAPABILITY_DATA_01, struct capdata01);
> EXPORT_SYMBOL_NS_GPL(lwmi_cd01_get_data, "LENOVO_WMI_CD");
>
> +DEF_LWMI_CDXX_GET_DATA(cd_fan, LENOVO_FAN_TEST_DATA, struct capdata_fan);
> +EXPORT_SYMBOL_NS_GPL(lwmi_cd_fan_get_data, "LENOVO_WMI_CD");
> +
> /**
> * lwmi_cd_cache() - Cache all WMI data block information
> * @priv: lenovo-wmi-capdata driver data.
> @@ -175,6 +194,9 @@ static int lwmi_cd_cache(struct lwmi_cd_priv *priv)
> p = &priv->list->cd01[0];
> size = sizeof(priv->list->cd01[0]);
> break;
> + case LENOVO_FAN_TEST_DATA:
> + /* Done by lwmi_cd_alloc() => lwmi_cd_fan_list_alloc_cache(). */
> + return 0;
> default:
> return -EINVAL;
> }
> @@ -197,6 +219,78 @@ static int lwmi_cd_cache(struct lwmi_cd_priv *priv)
> return 0;
> }
>
> +/**
> + * lwmi_cd_fan_list_alloc_cache() - Alloc and cache Fan Test Data list
> + * @priv: lenovo-wmi-capdata driver data.
> + * @listptr: Pointer to returned cd_list pointer.
> + *
> + * Return: count of fans found, or an error.
> + */
> +static int lwmi_cd_fan_list_alloc_cache(struct lwmi_cd_priv *priv, struct cd_list **listptr)
> +{
> + u32 count, *fan_ids, *fan_min_rpms, *fan_max_rpms;
> + union acpi_object *ret_obj __free(kfree) = NULL;
> + struct block { u32 nr; u32 data[]; } *block;
> + struct cd_list *list;
> + size_t size;
> + int idx;
> +
> + ret_obj = wmidev_block_query(priv->wdev, 0);
> + if (!ret_obj)
> + return -ENODEV;
> +
> + /*
> + * This is usually caused by a dummy ACPI method. Do not return an error
> + * as failing to probe this device will result in master driver being
> + * unbound - this behavior aligns with lwmi_cd_cache().
> + */
> + if (ret_obj->type != ACPI_TYPE_BUFFER) {
> + count = 0;
> + goto alloc;
> + }
> +
> + size = ret_obj->buffer.length;
> + block = (struct block *)ret_obj->buffer.pointer;
> +
> + count = size >= sizeof(*block) ? block->nr : 0;
> + if (size < struct_size(block, data, count * 3)) {
> + dev_warn(&priv->wdev->dev,
> + "incomplete fan test data block: %zu < %zu, ignoring\n",
> + size, struct_size(block, data, count * 3));
> + count = 0;
> + }
> +
> + if (count == 0)
> + goto alloc;
> +
> + if (count > U8_MAX) {
> + dev_warn(&priv->wdev->dev,
> + "too many fans reported: %u > %u, truncating\n",
> + count, U8_MAX);
> + count = U8_MAX;
> + }
> +
> + fan_ids = &block->data[0];
> + fan_max_rpms = &block->data[count];
> + fan_min_rpms = &block->data[count * 2];
> +
> +alloc:
> + list = devm_kzalloc(&priv->wdev->dev, struct_size(list, cd_fan, count), GFP_KERNEL);
> + if (!list)
> + return -ENOMEM;
> +
> + for (idx = 0; idx < count; idx++) {
> + list->cd_fan[idx] = (struct capdata_fan) {
> + .id = fan_ids[idx],
> + .min_rpm = fan_min_rpms[idx],
> + .max_rpm = fan_max_rpms[idx],
> + };
> + }
> +
> + *listptr = list;
> + return count;
> +}
> +
> /**
> * lwmi_cd_alloc() - Allocate a cd_list struct in drvdata
> * @priv: lenovo-wmi-capdata driver data.
> @@ -222,6 +316,12 @@ static int lwmi_cd_alloc(struct lwmi_cd_priv *priv, enum lwmi_cd_type type)
> case LENOVO_CAPABILITY_DATA_01:
> list_size = struct_size(list, cd01, count);
> break;
> + case LENOVO_FAN_TEST_DATA:
> + count = lwmi_cd_fan_list_alloc_cache(priv, &list);
> + if (count < 0)
> + return count;
> +
> + goto got_list;
> default:
> return -EINVAL;
> }
> @@ -230,6 +330,7 @@ static int lwmi_cd_alloc(struct lwmi_cd_priv *priv, enum lwmi_cd_type type)
> if (!list)
> return -ENOMEM;
>
> +got_list:
> ret = devm_mutex_init(&priv->wdev->dev, &list->list_mutex);
> if (ret)
> return ret;
> @@ -368,6 +469,7 @@ static void lwmi_cd_remove(struct wmi_device *wdev)
> static const struct wmi_device_id lwmi_cd_id_table[] = {
> { LWMI_CD_WDEV_ID(LENOVO_CAPABILITY_DATA_00) },
> { LWMI_CD_WDEV_ID(LENOVO_CAPABILITY_DATA_01) },
> + { LWMI_CD_WDEV_ID(LENOVO_FAN_TEST_DATA) },
> {}
> };
>
> diff --git a/drivers/platform/x86/lenovo/wmi-capdata.h b/drivers/platform/x86/lenovo/wmi-capdata.h
> index a6f0cb006e745..52bc215ac43d8 100644
> --- a/drivers/platform/x86/lenovo/wmi-capdata.h
> +++ b/drivers/platform/x86/lenovo/wmi-capdata.h
> @@ -26,13 +26,21 @@ struct capdata01 {
> u32 max_value;
> };
>
> +struct capdata_fan {
> + u32 id;
> + u32 min_rpm;
> + u32 max_rpm;
> +};
> +
> struct lwmi_cd_binder {
> struct cd_list *cd00_list;
> struct cd_list *cd01_list;
> + struct cd_list *cd_fan_list;
> };
>
> int lwmi_cd00_get_data(struct cd_list *list, u32 attribute_id, struct capdata00 *output);
> int lwmi_cd01_get_data(struct cd_list *list, u32 attribute_id, struct capdata01 *output);
> +int lwmi_cd_fan_get_data(struct cd_list *list, u32 attribute_id, struct capdata_fan *output);
> void lwmi_cd_match_add_all(struct device *master, struct component_match **matchptr);
>
> #endif /* !_LENOVO_WMI_CAPDATA_H_ */
> --
> 2.51.0
>
Reviewed-by: Derek J. Clark <derekjohn.clark@gmail.com>
Thanks,
Derek
© 2016 - 2026 Red Hat, Inc.