diff mbox

[v2,10/10,media] st-delta: debug: trace stream/frame information & summary

Message ID 1479468336-26199-11-git-send-email-hugues.fruchet@st.com (mailing list archive)
State New, archived
Headers show

Commit Message

Hugues FRUCHET Nov. 18, 2016, 11:25 a.m. UTC 
Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
---
 drivers/media/platform/sti/delta/Makefile      |  2 +-
 drivers/media/platform/sti/delta/delta-debug.c | 72 ++++++++++++++++++++++++++
 drivers/media/platform/sti/delta/delta-debug.h | 18 +++++++
 drivers/media/platform/sti/delta/delta-v4l2.c  | 29 +++++++++--
 4 files changed, 116 insertions(+), 5 deletions(-)
 create mode 100644 drivers/media/platform/sti/delta/delta-debug.c
 create mode 100644 drivers/media/platform/sti/delta/delta-debug.h

Comments

Hans Verkuil Nov. 21, 2016, 2:08 p.m. UTC | #1 
On 18/11/16 12:25, Hugues Fruchet wrote:
> Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
> ---
>  drivers/media/platform/sti/delta/Makefile      |  2 +-
>  drivers/media/platform/sti/delta/delta-debug.c | 72 ++++++++++++++++++++++++++
>  drivers/media/platform/sti/delta/delta-debug.h | 18 +++++++
>  drivers/media/platform/sti/delta/delta-v4l2.c  | 29 +++++++++--
>  4 files changed, 116 insertions(+), 5 deletions(-)
>  create mode 100644 drivers/media/platform/sti/delta/delta-debug.c
>  create mode 100644 drivers/media/platform/sti/delta/delta-debug.h
>
> 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..f1bc64e
> --- /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_info(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 93a0f90..5586a97 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"
> @@ -438,11 +439,13 @@ 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;
> @@ -465,11 +468,13 @@ 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;
> @@ -652,6 +657,7 @@ 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;
>
> @@ -703,6 +709,10 @@ 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;
> @@ -1321,10 +1331,12 @@ static int delta_vb2_au_start_streaming(struct vb2_queue *q,
>  	struct delta_dev *delta = ctx->dev;
>  	const struct delta_dec *dec = ctx->dec;
>  	struct delta_au *au;
> +	unsigned char str2[100] = "";
>  	int ret = 0;
>  	struct vb2_v4l2_buffer *vbuf = NULL;
>  	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
>  	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
> +	unsigned char str[100] = "";

That's a bit weird that 'str2' comes before 'str'. I suggest grouping 
them together
and renaming 'str' to 'str1'.

>
>  	if ((ctx->state != DELTA_STATE_WF_FORMAT) &&
>  	    (ctx->state != DELTA_STATE_WF_STREAMINFO))
> @@ -1385,6 +1397,10 @@ static int delta_vb2_au_start_streaming(struct vb2_queue *q,
>
>  	ctx->state = DELTA_STATE_READY;
>
> +	dev_info(delta->dev, "%s %s => %s\n", ctx->name,
> +		 delta_streaminfo_str(streaminfo, str, sizeof(str)),
> +		 delta_frameinfo_str(frameinfo, str2, sizeof(str2)));
> +
>  	delta_au_done(ctx, au, ret);
>  	return 0;
>
> @@ -1705,6 +1721,11 @@ 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);
>

Looks good otherwise!

	Hans
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Hugues FRUCHET Nov. 21, 2016, 4:44 p.m. UTC | #2 
On 11/21/2016 03:08 PM, Hans Verkuil wrote:
> On 18/11/16 12:25, Hugues Fruchet wrote:
>> Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
>> ---
>>  drivers/media/platform/sti/delta/Makefile      |  2 +-
>>  drivers/media/platform/sti/delta/delta-debug.c | 72 ++++++++++++++++++++++++++
>>  drivers/media/platform/sti/delta/delta-debug.h | 18 +++++++
>>  drivers/media/platform/sti/delta/delta-v4l2.c  | 29 +++++++++--
>>  4 files changed, 116 insertions(+), 5 deletions(-)
>>  create mode 100644 drivers/media/platform/sti/delta/delta-debug.c
>>  create mode 100644 drivers/media/platform/sti/delta/delta-debug.h
>>
>> 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..f1bc64e
>> --- /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_info(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 93a0f90..5586a97 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"
>> @@ -438,11 +439,13 @@ 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;
>> @@ -465,11 +468,13 @@ 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;
>> @@ -652,6 +657,7 @@ 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;
>>
>> @@ -703,6 +709,10 @@ 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;
>> @@ -1321,10 +1331,12 @@ static int delta_vb2_au_start_streaming(struct vb2_queue *q,
>>  	struct delta_dev *delta = ctx->dev;
>>  	const struct delta_dec *dec = ctx->dec;
>>  	struct delta_au *au;
>> +	unsigned char str2[100] = "";
>>  	int ret = 0;
>>  	struct vb2_v4l2_buffer *vbuf = NULL;
>>  	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
>>  	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
>> +	unsigned char str[100] = "";
>
> That's a bit weird that 'str2' comes before 'str'. I suggest grouping
> them together
> and renaming 'str' to 'str1'.

Of course, I will refactor with str1/str2.

>
>>
>>  	if ((ctx->state != DELTA_STATE_WF_FORMAT) &&
>>  	    (ctx->state != DELTA_STATE_WF_STREAMINFO))
>> @@ -1385,6 +1397,10 @@ static int delta_vb2_au_start_streaming(struct vb2_queue *q,
>>
>>  	ctx->state = DELTA_STATE_READY;
>>
>> +	dev_info(delta->dev, "%s %s => %s\n", ctx->name,
>> +		 delta_streaminfo_str(streaminfo, str, sizeof(str)),
>> +		 delta_frameinfo_str(frameinfo, str2, sizeof(str2)));
>> +
>>  	delta_au_done(ctx, au, ret);
>>  	return 0;
>>
>> @@ -1705,6 +1721,11 @@ 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);
>>
>
> Looks good otherwise!
>
> 	Hans
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diff mbox

Patch

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..f1bc64e
--- /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_info(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 93a0f90..5586a97 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"
@@ -438,11 +439,13 @@  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;
@@ -465,11 +468,13 @@  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;
@@ -652,6 +657,7 @@  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;
 
@@ -703,6 +709,10 @@  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;
@@ -1321,10 +1331,12 @@  static int delta_vb2_au_start_streaming(struct vb2_queue *q,
 	struct delta_dev *delta = ctx->dev;
 	const struct delta_dec *dec = ctx->dec;
 	struct delta_au *au;
+	unsigned char str2[100] = "";
 	int ret = 0;
 	struct vb2_v4l2_buffer *vbuf = NULL;
 	struct delta_streaminfo *streaminfo = &ctx->streaminfo;
 	struct delta_frameinfo *frameinfo = &ctx->frameinfo;
+	unsigned char str[100] = "";
 
 	if ((ctx->state != DELTA_STATE_WF_FORMAT) &&
 	    (ctx->state != DELTA_STATE_WF_STREAMINFO))
@@ -1385,6 +1397,10 @@  static int delta_vb2_au_start_streaming(struct vb2_queue *q,
 
 	ctx->state = DELTA_STATE_READY;
 
+	dev_info(delta->dev, "%s %s => %s\n", ctx->name,
+		 delta_streaminfo_str(streaminfo, str, sizeof(str)),
+		 delta_frameinfo_str(frameinfo, str2, sizeof(str2)));
+
 	delta_au_done(ctx, au, ret);
 	return 0;
 
@@ -1705,6 +1721,11 @@  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);