drm/tegra: Remove bogus tegra_framebuffer structure

Tegra uses the CMA FB helpers so framebuffers passed to the driver need
to use the corresponding functions to access the underlying GEM objects.

This used to work because struct tegra_framebuffer was sufficiently
similar to struct drm_fb_cma but that isn't guaranteed to stay that way.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

drivers/gpu/drm/tegra/dc.c

@@ -158,7 +158,7 @@ static int tegra_crtc_mode_set(struct drm_crtc *crtc,
 			       struct drm_display_mode *adjusted,
 			       int x, int y, struct drm_framebuffer *old_fb)
 {
-	struct tegra_framebuffer *fb = to_tegra_fb(crtc->fb);
+	struct drm_gem_cma_object *gem = drm_fb_cma_get_gem_obj(crtc->fb, 0);
 	struct tegra_dc *dc = to_tegra_dc(crtc);
 	unsigned int h_dda, v_dda, bpp;
 	struct tegra_dc_window win;

drivers/gpu/drm/tegra/drm.h

@@ -18,16 +18,6 @@
 #include <drm/drm_fb_cma_helper.h>
 #include <drm/drm_fixed.h>
 
-struct tegra_framebuffer {
-	struct drm_framebuffer base;
-	struct drm_gem_cma_object *obj;
-};
-
-static inline struct tegra_framebuffer *to_tegra_fb(struct drm_framebuffer *fb)
-{
-	return container_of(fb, struct tegra_framebuffer, base);
-}
-
 struct host1x {
 	struct drm_device *drm;
 	struct device *dev;
@@ -44,7 +34,6 @@ struct host1x {
 	struct list_head clients;
 
 	struct drm_fbdev_cma *fbdev;
-	struct tegra_framebuffer fb;
 };
 
 struct host1x_client;