drm/i915: implement crtc helper semantics relied upon by the fb helper

Yikes!

But yeah, we have to do this until someone volunteers to clean up the
fb helper and rid it of its incetious relationship with the crtc
helper code.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index c10fb2e57af26861a0d80fdce1ef1013b560f14f..71cb90d763bd9492499149737e5cd7bf1d9a66a7 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6934,6 +6934,12 @@ static int intel_crtc_set_config(struct drm_mode_set *set)
        if (!set->mode)
                set->fb = NULL;
 
+       /* The fb helper likes to play gross jokes with ->mode_set_config.
+        * Unfortunately the crtc helper doesn't do much at all for this case,
+        * so we have to cope with this madness until the fb helper is fixed up. */
+       if (set->fb && set->num_connectors == 0)
+               return 0;
+
        if (set->fb) {
                DRM_DEBUG_KMS("[CRTC:%d] [FB:%d] #connectors=%d (x y) (%i %i)\n",
                                set->crtc->base.id, set->fb->base.id,