V4L/DVB (5438): Fix ivtv yuv threshold handling

Modifies automatic mode selection for yuv playback. Behaviour is now that
source video with a vertical resolution below that of the currently set
broadcast mode will be treated as progressive. Video with a vertical
resolution greater or equal to the current broadcast mode (up to 576 lines)
will be treated as interlaced.
Signed-off-by: Ian Armstrong <ian@iarmst.demon.co.uk>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/ivtv/ivtv-driver.c

@@ -116,7 +116,7 @@ static int dec_yuv_buffers = IVTV_DEFAULT_DEC_YUV_BUFFERS;
 static int dec_vbi_buffers = IVTV_DEFAULT_DEC_VBI_BUFFERS;
 
 static int ivtv_yuv_mode = 0;
-static int ivtv_yuv_threshold=480;
+static int ivtv_yuv_threshold=-1;
 static int ivtv_pci_latency = 1;
 
 int ivtv_debug = 0;

drivers/media/video/ivtv/ivtv-driver.h

@@ -606,7 +606,6 @@ struct yuv_playback_info
 
 	int lace_mode;
 	int lace_threshold;
-	int lace_threshold_last;
 	int lace_sync_field;
 
 	atomic_t next_dma_frame;

drivers/media/video/ivtv/ivtv-yuv.c

@@ -613,16 +613,19 @@ static void ivtv_yuv_handle_vertical(struct ivtv *itv, struct yuv_frame_info *wi
 	}
 
 	itv->yuv_info.frame_interlaced_last = itv->yuv_info.frame_interlaced;
-	itv->yuv_info.lace_threshold_last = itv->yuv_info.lace_threshold;
 }
 
 /* Modify the supplied coordinate information to fit the visible osd area */
 static u32 ivtv_yuv_window_setup (struct ivtv *itv, struct yuv_frame_info *window)
 {
-	int osd_crop;
+	int osd_crop, lace_threshold;
 	u32 osd_scale;
 	u32 yuv_update = 0;
 
+	lace_threshold = itv->yuv_info.lace_threshold;
+	if (lace_threshold < 0)
+		lace_threshold = itv->yuv_info.decode_height - 1;
+
 	/* Work out the lace settings */
 	switch (itv->yuv_info.lace_mode) {
 		case IVTV_YUV_MODE_PROGRESSIVE: /* Progressive mode */
@@ -639,7 +642,7 @@ static u32 ivtv_yuv_window_setup (struct ivtv *itv, struct yuv_frame_info *windo
 			break;
 
 		case IVTV_YUV_MODE_AUTO:
-			if (window->tru_h <= itv->yuv_info.lace_threshold || window->tru_h > 576 || window->tru_w > 720){
+			if (window->tru_h <= lace_threshold || window->tru_h > 576 || window->tru_w > 720){
 				itv->yuv_info.frame_interlaced = 0;
 				if ((window->tru_h < 512) ||
 				  (window->tru_h > 576 && window->tru_h < 1021) ||