drm/atomic-helper: Make crtc helper funcs optional

Allow drivers to call drm_atomic_helper_check_modeset() without
having the crtc helper funcs specified. i915 doesn't need those
anymore.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190708125325.16576-3-ville.syrjala@linux.intel.com
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 9d7e4da6c2929bcf8b7f63d56c7f4b554d61c03b..e41db0f202ca4f5e913991abb6f11107e787b076 100644 (file)
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -471,7 +471,7 @@ mode_fixup(struct drm_atomic_state *state)
                        continue;
 
                funcs = crtc->helper_private;
-               if (!funcs->mode_fixup)
+               if (!funcs || !funcs->mode_fixup)
                        continue;
 
                ret = funcs->mode_fixup(crtc, &new_crtc_state->mode,