2 files changed, 44 insertions, 0 deletions

diff --git a/drivers/video/omap2/dss/dispc.c b/drivers/video/omap2/dss/dispc.c
index 80314bd3427d..67548839ff51 100644
--- a/drivers/video/omap2/dss/dispc.c
+++ b/drivers/video/omap2/dss/dispc.c
@@ -2320,6 +2320,46 @@ static int dispc_ovl_calc_scaling(unsigned long pclk, unsigned long lclk,
         return 0;
 }
 
+int dispc_ovl_check(enum omap_plane plane, enum omap_channel channel,
+                const struct omap_overlay_info *oi,
+                const struct omap_video_timings *timings,
+                int *x_predecim, int *y_predecim)
+{
+        enum omap_overlay_caps caps = dss_feat_get_overlay_caps(plane);
+        bool five_taps = true;
+        bool fieldmode = 0;
+        u16 in_height = oi->height;
+        u16 in_width = oi->width;
+        bool ilace = timings->interlace;
+        u16 out_width, out_height;
+        int pos_x = oi->pos_x;
+        unsigned long pclk = dispc_mgr_pclk_rate(channel);
+        unsigned long lclk = dispc_mgr_lclk_rate(channel);
+
+        out_width = oi->out_width == 0 ? oi->width : oi->out_width;
+        out_height = oi->out_height == 0 ? oi->height : oi->out_height;
+
+        if (ilace && oi->height == out_height)
+                fieldmode = 1;
+
+        if (ilace) {
+                if (fieldmode)
+                        in_height /= 2;
+                out_height /= 2;
+
+                DSSDBG("adjusting for ilace: height %d, out_height %d\n",
+                                in_height, out_height);
+        }
+
+        if (!dss_feat_color_mode_supported(plane, oi->color_mode))
+                return -EINVAL;
+
+        return dispc_ovl_calc_scaling(pclk, lclk, caps, timings, in_width,
+                        in_height, out_width, out_height, oi->color_mode,
+                        &five_taps, x_predecim, y_predecim, pos_x,
+                        oi->rotation_type, false);
+}
+
 static int dispc_ovl_setup_common(enum omap_plane plane,
                 enum omap_overlay_caps caps, u32 paddr, u32 p_uv_addr,
                 u16 screen_width, int pos_x, int pos_y, u16 width, u16 height,
diff --git a/drivers/video/omap2/dss/dss.h b/drivers/video/omap2/dss/dss.h
index 2754bcb231d6..180b381fd120 100644
--- a/drivers/video/omap2/dss/dss.h
+++ b/drivers/video/omap2/dss/dss.h
@@ -423,6 +423,10 @@ int dispc_ovl_enable(enum omap_plane plane, bool enable);
 bool dispc_ovl_enabled(enum omap_plane plane);
 void dispc_ovl_set_channel_out(enum omap_plane plane,
                 enum omap_channel channel);
+int dispc_ovl_check(enum omap_plane plane, enum omap_channel channel,
+                const struct omap_overlay_info *oi,
+                const struct omap_video_timings *timings,
+                int *x_predecim, int *y_predecim);
 
 u32 dispc_mgr_get_vsync_irq(enum omap_channel channel);
 u32 dispc_mgr_get_framedone_irq(enum omap_channel channel);