diff --git a/drivers/media/platform/sti/delta/Makefile b/drivers/media/platform/sti/delta/Makefile
index 663be70..f95580e 100644
--- a/drivers/media/platform/sti/delta/Makefile
+++ b/drivers/media/platform/sti/delta/Makefile
@@ -1,5 +1,5 @@
 obj-$(CONFIG_VIDEO_STI_DELTA) := st-delta.o
-st-delta-y := delta-v4l2.o delta-mem.o delta-ipc.o
+st-delta-y := delta-v4l2.o delta-mem.o delta-ipc.o delta-debug.o
 
 # MJPEG support
 st-delta-$(CONFIG_VIDEO_STI_DELTA_MJPEG) += delta-mjpeg-hdr.o
diff --git a/drivers/media/platform/sti/delta/delta-debug.c b/drivers/media/platform/sti/delta/delta-debug.c
new file mode 100644
index 0000000..a7ebf2c
--- /dev/null
+++ b/drivers/media/platform/sti/delta/delta-debug.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) STMicroelectronics SA 2015
+ * Authors: Hugues Fruchet <hugues.fruchet@st.com>
+ *          Fabrice Lecoultre <fabrice.lecoultre@st.com>
+ *          for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include "delta.h"
+#include "delta-debug.h"
+
+char *delta_streaminfo_str(struct delta_streaminfo *s, char *str,
+			   unsigned int len)
+{
+	if (!s)
+		return NULL;
+
+	snprintf(str, len,
+		 "%4.4s %dx%d %s %s dpb=%d %s %s %s%dx%d@(%d,%d) %s%d/%d",
+		 (char *)&s->streamformat, s->width, s->height,
+		 s->profile, s->level, s->dpb,
+		 (s->field == V4L2_FIELD_NONE) ? "progressive" : "interlaced",
+		 s->other,
+		 s->flags & DELTA_STREAMINFO_FLAG_CROP ? "crop=" : "",
+		 s->crop.width, s->crop.height,
+		 s->crop.left, s->crop.top,
+		 s->flags & DELTA_STREAMINFO_FLAG_PIXELASPECT ? "par=" : "",
+		 s->pixelaspect.numerator,
+		 s->pixelaspect.denominator);
+
+	return str;
+}
+
+char *delta_frameinfo_str(struct delta_frameinfo *f, char *str,
+			  unsigned int len)
+{
+	if (!f)
+		return NULL;
+
+	snprintf(str, len,
+		 "%4.4s %dx%d aligned %dx%d %s %s%dx%d@(%d,%d) %s%d/%d",
+		 (char *)&f->pixelformat, f->width, f->height,
+		 f->aligned_width, f->aligned_height,
+		 (f->field == V4L2_FIELD_NONE) ? "progressive" : "interlaced",
+		 f->flags & DELTA_STREAMINFO_FLAG_CROP ? "crop=" : "",
+		 f->crop.width, f->crop.height,
+		 f->crop.left, f->crop.top,
+		 f->flags & DELTA_STREAMINFO_FLAG_PIXELASPECT ? "par=" : "",
+		 f->pixelaspect.numerator,
+		 f->pixelaspect.denominator);
+
+	return str;
+}
+
+void delta_trace_summary(struct delta_ctx *ctx)
+{
+	struct delta_dev *delta = ctx->dev;
+	struct delta_streaminfo *s = &ctx->streaminfo;
+	unsigned char str[100] = "";
+
+	if (!(ctx->flags & DELTA_FLAG_STREAMINFO))
+		return;
+
+	dev_dbg(delta->dev, "%s %s, %d frames decoded, %d frames output, %d frames dropped, %d stream errors, %d decode errors",
+		ctx->name,
+		delta_streaminfo_str(s, str, sizeof(str)),
+		ctx->decoded_frames,
+		ctx->output_frames,
+		ctx->dropped_frames,
+		ctx->stream_errors,
+		ctx->decode_errors);
+}
diff --git a/drivers/media/platform/sti/delta/delta-debug.h b/drivers/media/platform/sti/delta/delta-debug.h
new file mode 100644
index 0000000..955c158
--- /dev/null
+++ b/drivers/media/platform/sti/delta/delta-debug.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) STMicroelectronics SA 2015
+ * Authors: Hugues Fruchet <hugues.fruchet@st.com>
+ *          Fabrice Lecoultre <fabrice.lecoultre@st.com>
+ *          for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#ifndef DELTA_DEBUG_H
+#define DELTA_DEBUG_H
+
+char *delta_streaminfo_str(struct delta_streaminfo *s, char *str,
+			   unsigned int len);
+char *delta_frameinfo_str(struct delta_frameinfo *f, char *str,
+			  unsigned int len);
+void delta_trace_summary(struct delta_ctx *ctx);
+
+#endif /* DELTA_DEBUG_H */
diff --git a/drivers/media/platform/sti/delta/delta-v4l2.c b/drivers/media/platform/sti/delta/delta-v4l2.c
index 82aef8b..9fc0093 100644
--- a/drivers/media/platform/sti/delta/delta-v4l2.c
+++ b/drivers/media/platform/sti/delta/delta-v4l2.c
@@ -17,6 +17,7 @@
 #include <media/videobuf2-dma-contig.h>
 
 #include "delta.h"
+#include "delta-debug.h"
 #include "delta-ipc.h"
 
 #define DELTA_NAME	"st-delta"
@@ -446,11 +447,13 @@ static int delta_g_fmt_stream(struct file *file, void *fh,
 	struct delta_dev *delta = ctx->dev;
 	struct v4l2_pix_format *pix = &f->fmt.pix;
 	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
+	unsigned char str[100] = "";
 
 	if (!(ctx->flags & DELTA_FLAG_STREAMINFO))
 		dev_dbg(delta->dev,
-			"%s V4L2 GET_FMT (OUTPUT): no stream information available, using default\n",
-			ctx->name);
+			"%s V4L2 GET_FMT (OUTPUT): no stream information available, default to %s\n",
+			ctx->name,
+			delta_streaminfo_str(streaminfo, str, sizeof(str)));
 
 	pix->pixelformat = streaminfo->streamformat;
 	pix->width = streaminfo->width;
@@ -473,11 +476,13 @@ static int delta_g_fmt_frame(struct file *file, void *fh, struct v4l2_format *f)
 	struct v4l2_pix_format *pix = &f->fmt.pix;
 	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
 	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
+	unsigned char str[100] = "";
 
 	if (!(ctx->flags & DELTA_FLAG_FRAMEINFO))
 		dev_dbg(delta->dev,
-			"%s V4L2 GET_FMT (CAPTURE): no frame information available, using default\n",
-			ctx->name);
+			"%s V4L2 GET_FMT (CAPTURE): no frame information available, default to %s\n",
+			ctx->name,
+			delta_frameinfo_str(frameinfo, str, sizeof(str)));
 
 	pix->pixelformat = frameinfo->pixelformat;
 	pix->width = frameinfo->aligned_width;
@@ -660,6 +665,7 @@ static int delta_s_fmt_frame(struct file *file, void *fh, struct v4l2_format *f)
 	const struct delta_dec *dec = ctx->dec;
 	struct v4l2_pix_format *pix = &f->fmt.pix;
 	struct delta_frameinfo frameinfo;
+	unsigned char str[100] = "";
 	struct vb2_queue *vq;
 	int ret;
 
@@ -712,6 +718,10 @@ static int delta_s_fmt_frame(struct file *file, void *fh, struct v4l2_format *f)
 
 	ctx->flags |= DELTA_FLAG_FRAMEINFO;
 	ctx->frameinfo = frameinfo;
+	dev_dbg(delta->dev,
+		"%s V4L2 SET_FMT (CAPTURE): frameinfo updated to %s\n",
+		ctx->name,
+		delta_frameinfo_str(&frameinfo, str, sizeof(str)));
 
 	pix->pixelformat = frameinfo.pixelformat;
 	pix->width = frameinfo.aligned_width;
@@ -1323,6 +1333,8 @@ static int delta_vb2_au_start_streaming(struct vb2_queue *q,
 	struct vb2_v4l2_buffer *vbuf = NULL;
 	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
 	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
+	unsigned char str1[100] = "";
+	unsigned char str2[100] = "";
 
 	if ((ctx->state != DELTA_STATE_WF_FORMAT) &&
 	    (ctx->state != DELTA_STATE_WF_STREAMINFO))
@@ -1384,6 +1396,10 @@ static int delta_vb2_au_start_streaming(struct vb2_queue *q,
 
 	ctx->state = DELTA_STATE_READY;
 
+	dev_dbg(delta->dev, "%s %s => %s\n", ctx->name,
+		delta_streaminfo_str(streaminfo, str1, sizeof(str1)),
+		delta_frameinfo_str(frameinfo, str2, sizeof(str2)));
+
 	delta_au_done(ctx, au, ret);
 	return 0;
 
@@ -1711,6 +1727,12 @@ static int delta_release(struct file *file)
 	/* close decoder */
 	call_dec_op(dec, close, ctx);
 
+	/*
+	 * trace a summary of instance
+	 * before closing (debug purpose)
+	 */
+	delta_trace_summary(ctx);
+
 	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
 
 	v4l2_fh_del(&ctx->fh);
