drm/tegra: Don't disable unused planes

When a plane isn't in use it isn't attached to a CRTC and therefore the
DC registers aren't available for programming.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

diff --git a/drivers/gpu/host1x/drm/dc.c b/drivers/gpu/host1x/drm/dc.c
index 8c04943f82e3531d75ee5565eab06c16e6f46b16..98f60d827558ee539b56dee3426f8b7a6bf3a6db 100644 (file)
--- a/drivers/gpu/host1x/drm/dc.c
+++ b/drivers/gpu/host1x/drm/dc.c
@@ -79,6 +79,9 @@ static int tegra_plane_disable(struct drm_plane *plane)
        struct tegra_plane *p = to_tegra_plane(plane);
        unsigned long value;
 
+       if (!plane->crtc)
+               return 0;
+
        value = WINDOW_A_SELECT << p->index;
        tegra_dc_writel(dc, value, DC_CMD_DISPLAY_WINDOW_HEADER);