#define  VE_SRC_TB_EDGE_DET_BOT                GENMASK(28, VE_SRC_TB_EDGE_DET_BOT_SHF)
 
 #define VE_MODE_DETECT_STATUS          0x098
-#define  VE_MODE_DETECT_H_PIXELS       GENMASK(11, 0)
+#define  VE_MODE_DETECT_H_PERIOD       GENMASK(11, 0)
 #define  VE_MODE_DETECT_V_LINES_SHF    16
 #define  VE_MODE_DETECT_V_LINES                GENMASK(27, VE_MODE_DETECT_V_LINES_SHF)
 #define  VE_MODE_DETECT_STATUS_VSYNC   BIT(28)
 #define  VE_SYNC_STATUS_VSYNC_SHF      16
 #define  VE_SYNC_STATUS_VSYNC          GENMASK(27, VE_SYNC_STATUS_VSYNC_SHF)
 
+#define VE_H_TOTAL_PIXELS              0x0A0
+
 #define VE_INTERRUPT_CTRL              0x304
 #define VE_INTERRUPT_STATUS            0x308
 #define  VE_INTERRUPT_MODE_DETECT_WD   BIT(0)
        u32 src_lr_edge;
        u32 src_tb_edge;
        u32 sync;
+       u32 htotal;
        struct v4l2_bt_timings *det = &video->detected_timings;
 
        det->width = MIN_WIDTH;
                src_tb_edge = aspeed_video_read(video, VE_SRC_TB_EDGE_DET);
                mds = aspeed_video_read(video, VE_MODE_DETECT_STATUS);
                sync = aspeed_video_read(video, VE_SYNC_STATUS);
+               htotal = aspeed_video_read(video, VE_H_TOTAL_PIXELS);
 
                video->frame_bottom = (src_tb_edge & VE_SRC_TB_EDGE_DET_BOT) >>
                        VE_SRC_TB_EDGE_DET_BOT_SHF;
                        VE_SRC_LR_EDGE_DET_RT_SHF;
                video->frame_left = src_lr_edge & VE_SRC_LR_EDGE_DET_LEFT;
                det->hfrontporch = video->frame_left;
-               det->hbackporch = (mds & VE_MODE_DETECT_H_PIXELS) -
-                       video->frame_right;
+               det->hbackporch = htotal - video->frame_right;
                det->hsync = sync & VE_SYNC_STATUS_HSYNC;
                if (video->frame_left > video->frame_right)
                        continue;