platform/x86: wmi: Add wmidev_block_set()

Currently, WMI drivers have to use the deprecated GUID-based
interface when setting data blocks. This prevents those
drivers from fully moving away from this interface.

Provide wmidev_block_set() so drivers using wmi_set_block() can
fully migrate to the modern bus-based interface.

Tested with a custom SSDT from the Intel Slim Bootloader project.
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20231103182526.3524-1-W_Armin@gmx.deReviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/x86/wmi.c

@@ -536,41 +536,50 @@ EXPORT_SYMBOL_GPL(wmidev_block_query);
  *
  * Return: acpi_status signaling success or error.
  */
-acpi_status wmi_set_block(const char *guid_string, u8 instance,
-			  const struct acpi_buffer *in)
+acpi_status wmi_set_block(const char *guid_string, u8 instance, const struct acpi_buffer *in)
 {
-	struct wmi_block *wblock;
-	struct guid_block *block;
 	struct wmi_device *wdev;
-	acpi_handle handle;
-	struct acpi_object_list input;
-	union acpi_object params[2];
-	char method[WMI_ACPI_METHOD_NAME_SIZE];
 	acpi_status status;
 
-	if (!in)
-		return AE_BAD_DATA;
-
 	wdev = wmi_find_device_by_guid(guid_string);
 	if (IS_ERR(wdev))
 		return AE_ERROR;
 
-	wblock = container_of(wdev, struct wmi_block, dev);
-	block = &wblock->gblock;
-	handle = wblock->acpi_device->handle;
+	status =  wmidev_block_set(wdev, instance, in);
+	wmi_device_put(wdev);
 
-	if (block->instance_count <= instance) {
-		status = AE_BAD_PARAMETER;
+	return status;
+}
+EXPORT_SYMBOL_GPL(wmi_set_block);
 
-		goto err_wdev_put;
-	}
+/**
+ * wmidev_block_set - Write to a WMI block
+ * @wdev: A wmi bus device from a driver
+ * @instance: Instance index
+ * @in: Buffer containing new values for the data block
+ *
+ * Write contents of the input buffer to an ACPI-WMI data block.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in)
+{
+	struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
+	acpi_handle handle = wblock->acpi_device->handle;
+	struct guid_block *block = &wblock->gblock;
+	char method[WMI_ACPI_METHOD_NAME_SIZE];
+	struct acpi_object_list input;
+	union acpi_object params[2];
 
-	/* Check GUID is a data block */
-	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD)) {
-		status = AE_ERROR;
+	if (!in)
+		return AE_BAD_DATA;
 
-		goto err_wdev_put;
-	}
+	if (block->instance_count <= instance)
+		return AE_BAD_PARAMETER;
+
+	/* Check GUID is a data block */
+	if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
+		return AE_ERROR;
 
 	input.count = 2;
 	input.pointer = params;
@@ -582,14 +591,9 @@ acpi_status wmi_set_block(const char *guid_string, u8 instance,
 
 	get_acpi_method_name(wblock, 'S', method);
 
-	status = acpi_evaluate_object(handle, method, &input, NULL);
-
-err_wdev_put:
-	wmi_device_put(wdev);
-
-	return status;
+	return acpi_evaluate_object(handle, method, &input, NULL);
 }
-EXPORT_SYMBOL_GPL(wmi_set_block);
+EXPORT_SYMBOL_GPL(wmidev_block_set);
 
 static void wmi_dump_wdg(const struct guid_block *g)
 {

include/linux/wmi.h

@@ -35,6 +35,8 @@ extern acpi_status wmidev_evaluate_method(struct wmi_device *wdev,
 extern union acpi_object *wmidev_block_query(struct wmi_device *wdev,
 					     u8 instance);
 
+acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in);
+
 u8 wmidev_instance_count(struct wmi_device *wdev);
 
 extern int set_required_buffer_size(struct wmi_device *wdev, u64 length);