From: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Tue, 20 Mar 2012 14:46:03 +0000 (+0200)
Subject: drm: Reject mode set with current fb if no current fb is bound
X-Git-Tag: 2.1b_release~208
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3d8ffcb5d9c58234024c79f2bdd659f83dc6fef1;p=kernel%2Fkernel-mfld-blackbay.git

drm: Reject mode set with current fb if no current fb is bound

When doing a mode set with the special fb id -1, reject the mode set if
no fb is currently bound to the crtc.

Also remove the pointless list traversal to find the current crtc based
on the current crtc :)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 340f09b..d414775 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1964,7 +1964,7 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data,
 	struct drm_mode_config *config = &dev->mode_config;
 	struct drm_mode_crtc *crtc_req = data;
 	struct drm_mode_object *obj;
-	struct drm_crtc *crtc, *crtcfb;
+	struct drm_crtc *crtc;
 	struct drm_connector **connector_set = NULL, *connector;
 	struct drm_framebuffer *fb = NULL;
 	struct drm_display_mode *mode = NULL;
@@ -1991,14 +1991,12 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data,
 		/* If we have a mode we need a framebuffer. */
 		/* If we pass -1, set the mode with the currently bound fb */
 		if (crtc_req->fb_id == -1) {
-			list_for_each_entry(crtcfb,
-					    &dev->mode_config.crtc_list, head) {
-				if (crtcfb == crtc) {
-					DRM_DEBUG_KMS("Using current fb for "
-							"setmode\n");
-					fb = crtc->fb;
-				}
+			if (!crtc->fb) {
+				DRM_DEBUG_KMS("CRTC doesn't have current FB\n");
+				ret = -EINVAL;
+				goto out;
 			}
+			fb = crtc->fb;
 		} else {
 			obj = drm_mode_object_find(dev, crtc_req->fb_id,
 						   DRM_MODE_OBJECT_FB);