drm: Extract __setplane_check()

Pull all the error checking out from __set_plane_internal() to a helper
function. We'll have another user of this soon.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180628135457.14647-1-ville.syrjala@linux.intel.com
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_plane.c

@@ -583,6 +583,52 @@ int drm_plane_check_pixel_format(struct drm_plane *plane,
 	return 0;
 }
 
+static int __setplane_check(struct drm_plane *plane,
+			    struct drm_crtc *crtc,
+			    struct drm_framebuffer *fb,
+			    int32_t crtc_x, int32_t crtc_y,
+			    uint32_t crtc_w, uint32_t crtc_h,
+			    uint32_t src_x, uint32_t src_y,
+			    uint32_t src_w, uint32_t src_h)
+{
+	int ret;
+
+	/* Check whether this plane is usable on this CRTC */
+	if (!(plane->possible_crtcs & drm_crtc_mask(crtc))) {
+		DRM_DEBUG_KMS("Invalid crtc for plane\n");
+		return -EINVAL;
+	}
+
+	/* Check whether this plane supports the fb pixel format. */
+	ret = drm_plane_check_pixel_format(plane, fb->format->format,
+					   fb->modifier);
+	if (ret) {
+		struct drm_format_name_buf format_name;
+
+		DRM_DEBUG_KMS("Invalid pixel format %s, modifier 0x%llx\n",
+			      drm_get_format_name(fb->format->format,
+						  &format_name),
+			      fb->modifier);
+		return ret;
+	}
+
+	/* Give drivers some help against integer overflows */
+	if (crtc_w > INT_MAX ||
+	    crtc_x > INT_MAX - (int32_t) crtc_w ||
+	    crtc_h > INT_MAX ||
+	    crtc_y > INT_MAX - (int32_t) crtc_h) {
+		DRM_DEBUG_KMS("Invalid CRTC coordinates %ux%u+%d+%d\n",
+			      crtc_w, crtc_h, crtc_x, crtc_y);
+		return -ERANGE;
+	}
+
+	ret = drm_framebuffer_check_src_coords(src_x, src_y, src_w, src_h, fb);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 /*
  * __setplane_internal - setplane handler for internal callers
  *
@@ -616,37 +662,9 @@ static int __setplane_internal(struct drm_plane *plane,
 		goto out;
 	}
 
-	/* Check whether this plane is usable on this CRTC */
-	if (!(plane->possible_crtcs & drm_crtc_mask(crtc))) {
-		DRM_DEBUG_KMS("Invalid crtc for plane\n");
-		ret = -EINVAL;
-		goto out;
-	}
-
-	/* Check whether this plane supports the fb pixel format. */
-	ret = drm_plane_check_pixel_format(plane, fb->format->format,
-					   fb->modifier);
-	if (ret) {
-		struct drm_format_name_buf format_name;
-		DRM_DEBUG_KMS("Invalid pixel format %s, modifier 0x%llx\n",
-			      drm_get_format_name(fb->format->format,
-						  &format_name),
-			      fb->modifier);
-		goto out;
-	}
-
-	/* Give drivers some help against integer overflows */
-	if (crtc_w > INT_MAX ||
-	    crtc_x > INT_MAX - (int32_t) crtc_w ||
-	    crtc_h > INT_MAX ||
-	    crtc_y > INT_MAX - (int32_t) crtc_h) {
-		DRM_DEBUG_KMS("Invalid CRTC coordinates %ux%u+%d+%d\n",
-			      crtc_w, crtc_h, crtc_x, crtc_y);
-		ret = -ERANGE;
-		goto out;
-	}
-
-	ret = drm_framebuffer_check_src_coords(src_x, src_y, src_w, src_h, fb);
+	ret = __setplane_check(plane, crtc, fb,
+			       crtc_x, crtc_y, crtc_w, crtc_h,
+			       src_x, src_y, src_w, src_h);
 	if (ret)
 		goto out;