gbm: Export a get modifiers

This patch originally had i965 specific code and was named:
commit 61cd3c52b868cf8cb90b06e53a382a921eb42754
Author: Ben Widawsky <[email protected]>
Date:   Thu Oct 20 18:21:24 2016 -0700

    gbm: Get modifiers from DRI

To accomplish this, two new query tokens are added to the extension:
__DRI_IMAGE_ATTRIB_MODIFIER_UPPER
__DRI_IMAGE_ATTRIB_MODIFIER_LOWER

The query extension only supported 32b queries, and modifiers are 64b,
so we needed two of them.

NOTE: The extension version is still set to 13, so none of this will
actually be called.

v2: Error handling of queryImage (Emil)

Signed-off-by: Ben Widawsky <[email protected]>
Reviewed-by: Jason Ekstrand <[email protected]>
Reviewed-by: Emil Velikov <[email protected]>

1 files changed, 19 insertions, 0 deletions

diff --git a/src/gbm/main/gbm.c b/src/gbm/main/gbm.c
index 7bacd8b86a6..19dc5db901a 100644
--- a/src/gbm/main/gbm.c
+++ b/src/gbm/main/gbm.c
@@ -280,6 +280,25 @@ gbm_bo_get_handle_for_plane(struct gbm_bo *bo, int plane)
    return bo->gbm->bo_get_handle(bo, plane);
 }
 
+/**
+ * Get the chosen modifier for the buffer object
+ *
+ * This function returns the modifier that was chosen for the object. These
+ * properties may be generic, or platform/implementation dependent.
+ *
+ * \param bo The buffer object
+ * \return Returns the selected modifier (chosen by the implementation) for the
+ * BO.
+ * \sa gbm_bo_create_with_modifiers() where possible modifiers are set
+ * \sa gbm_surface_create_with_modifiers() where possible modifiers are set
+ * \sa define DRM_FORMAT_MOD_* in drm_fourcc.h for possible modifiers
+ */
+GBM_EXPORT uint64_t
+gbm_bo_get_modifier(struct gbm_bo *bo)
+{
+   return bo->gbm->bo_get_modifier(bo);
+}
+
 /** Write data into the buffer object
  *
  * If the buffer object was created with the GBM_BO_USE_WRITE flag,