diff options
Diffstat (limited to 'include/drm/drm_mode_config.h')
| -rw-r--r-- | include/drm/drm_mode_config.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h index a18f73eb3cf6..5ffbb4ed5b35 100644 --- a/include/drm/drm_mode_config.h +++ b/include/drm/drm_mode_config.h @@ -58,6 +58,12 @@ struct drm_mode_config_funcs { * actual modifier used if the request doesn't have it specified, * ie. when (@mode_cmd->flags & DRM_MODE_FB_MODIFIERS) == 0. * + * IMPORTANT: These implied modifiers for legacy userspace must be + * stored in struct &drm_framebuffer, including all relevant metadata + * like &drm_framebuffer.pitches and &drm_framebuffer.offsets if the + * modifier enables additional planes beyond the fourcc pixel format + * code. This is required by the GETFB2 ioctl. + * * If the parameters are deemed valid and the backing storage objects in * the underlying memory manager all exist, then the driver allocates * a new &drm_framebuffer structure, subclassed to contain @@ -915,6 +921,13 @@ struct drm_mode_config { * @allow_fb_modifiers: * * Whether the driver supports fb modifiers in the ADDFB2.1 ioctl call. + * + * IMPORTANT: + * + * If this is set the driver must fill out the full implicit modifier + * information in their &drm_mode_config_funcs.fb_create hook for legacy + * userspace which does not set modifiers. Otherwise the GETFB2 ioctl is + * broken for modifier aware userspace. */ bool allow_fb_modifiers; |