acpi_video_get_levels
EXPORT_SYMBOL(acpi_video_get_levels);
result = acpi_video_get_levels(device->dev, &br, &max_level);
ret = acpi_video_get_levels(ACPI_COMPANION(&pdev->dev), &d->br, NULL);
extern int acpi_video_get_levels(struct acpi_device *device,