* pairs supported by this plane. The blob is a struct
* drm_format_modifier_blob. Without this property the plane doesn't
* support buffers with modifiers. Userspace cannot change this property.
+ *
+ * Note that userspace can check the &DRM_CAP_ADDFB2_MODIFIERS driver
+ * capability for general modifier support. If this flag is set then every
+ * plane will have the IN_FORMATS property, even when it only supports
+ * DRM_FORMAT_MOD_LINEAR. Before linux kernel release v5.1 there have been
+ * various bugs in this area with inconsistencies between the capability
+ * flag and per-plane properties.
*/
static unsigned int drm_num_planes(struct drm_device *dev)
format_modifier_count++;
}
- if (format_modifier_count)
+ /* autoset the cap and check for consistency across all planes */
+ if (format_modifier_count) {
+ drm_WARN_ON(dev, !config->allow_fb_modifiers &&
+ !list_empty(&config->plane_list));
config->allow_fb_modifiers = true;
+ } else {
+ drm_WARN_ON(dev, config->allow_fb_modifiers);
+ }
plane->modifier_count = format_modifier_count;
plane->modifiers = kmalloc_array(format_modifier_count,
* drm_universal_plane_init() to let the DRM managed resource infrastructure
* take care of cleanup and deallocation.
*
+ * Drivers supporting modifiers must set @format_modifiers on all their planes,
+ * even those that only support DRM_FORMAT_MOD_LINEAR.
+ *
* Returns:
* Zero on success, error code on failure.
*/