[PATCH 3/5] drm/gem: Clear mapping addresses for unused framebuffer planes

[Thomas Zimmermann]

Set the returned mapping address to NULL if a framebuffer plane does
not have a BO associated with it. Likewise, ignore mappings of NULL
during framebuffer unmap operations. Allows users of the functions to
perform unmap operations of certain BOs by themselfes.

Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
---
 drivers/gpu/drm/drm_gem_framebuffer_helper.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c 
b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index cc4465100cc2..15b0fe3ee7b6 100644
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -333,8 +333,10 @@ int drm_gem_fb_vmap(struct drm_framebuffer *fb, struct 
dma_buf_map map[DRM_FORMA
 
        for (i = 0; i < DRM_FORMAT_MAX_PLANES; ++i) {
                obj = drm_gem_fb_get_obj(fb, i);
-               if (!obj)
+               if (!obj) {
+                       dma_buf_map_clear(&map[i]);
                        continue;
+               }
                ret = drm_gem_vmap(obj, &map[i]);
                if (ret)
                        goto err_drm_gem_vunmap;
@@ -373,6 +375,8 @@ void drm_gem_fb_vunmap(struct drm_framebuffer *fb, struct 
dma_buf_map map[DRM_FO
                obj = drm_gem_fb_get_obj(fb, i);
                if (!obj)
                        continue;
+               if (dma_buf_map_is_null(&map[i]))
+                       continue;
                drm_gem_vunmap(obj, &map[i]);
        }
 }
-- 
2.32.0