[PATCH v1 0/9] media: tegra-video: Add support for capturing from HDMI-to-CSI bridge

[PATCH v1 0/9] media: tegra-video: Add support for capturing from HDMI-to-CSI bridge

[Sowjanya Komatineni]

This series includes below changes to allow capturing from HDMI-to-CSI bridges.
- Add DV timing, EDID and log status V4L2 IOCTLs
- Subscribe V4L2_EVENT_SOURCE_CHANGE
- Implement V4L2 device notify callback to report queue error on source change
  during active streaming.
- Add support for NV16 V4L2 Pixel format.

This series also include below fixes
- Allow format change for subdevs that don't have crop support.
- Correct V4L2 Pixel format for RGB888_1X24
- Enable VI pixel transform for YUV and RGB formats.


Sowjanya Komatineni (9):
  media: tegra-video: Use zero crop settings if subdev has no
    get_selection
  media: tegra-video: Enable VI pixel transform for YUV and RGB formats
  media: tegra-video: Fix V4L2 pixel format for RGB888_1X24
  media: tegra-video: Add support for V4L2_PIX_FMT_NV16
  media: tegra-video: Add DV timing support
  media: tegra-video: Add support for EDID ioctl ops
  media: tegra-video: Add support for VIDIOC_LOG_STATUS ioctl
  media: tegra-video: Add support for V4L2_EVENT_SOURCE_CHANGE
  media: tegra-video: Implement V4L2 device notify callback

 drivers/staging/media/tegra-video/tegra210.c |  30 ++++-
 drivers/staging/media/tegra-video/vi.c       | 171 ++++++++++++++++++++++++++-
 drivers/staging/media/tegra-video/video.c    |  18 +++
 3 files changed, 211 insertions(+), 8 deletions(-)

-- 
2.7.4

[PATCH v1 1/9] media: tegra-video: Use zero crop settings if subdev has no get_selection

[Sowjanya Komatineni]

Currently try format implementation doesn't check if subdevice has
get_selection ops implemented and returns -EINVAL on error from
direct v4l2_subdev_call of get_selection.

Selection API's are not mandatory for all V4L2 subdevices.

This patch fixes it by adding v4l2_subdev_has_ops check prior to
calling get_selection ops and continues with try or set format with
zero crop settings for subdevices that don't have get_selection and
returns -EINVAL only for subdevices that has get_selection ops.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/vi.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 560d8b3..7edd35c 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -533,11 +533,18 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
 	fse.code = fmtinfo->code;
 	ret = v4l2_subdev_call(subdev, pad, enum_frame_size, pad_cfg, &fse);
 	if (ret) {
-		ret = v4l2_subdev_call(subdev, pad, get_selection, NULL, &sdsel);
-		if (ret)
-			return -EINVAL;
-		pad_cfg->try_crop.width = sdsel.r.width;
-		pad_cfg->try_crop.height = sdsel.r.height;
+		if (!v4l2_subdev_has_op(subdev, pad, get_selection)) {
+			pad_cfg->try_crop.width = 0;
+			pad_cfg->try_crop.height = 0;
+		} else {
+			ret = v4l2_subdev_call(subdev, pad, get_selection,
+					       NULL, &sdsel);
+			if (ret)
+				return -EINVAL;
+
+			pad_cfg->try_crop.width = sdsel.r.width;
+			pad_cfg->try_crop.height = sdsel.r.height;
+		}
 	} else {
 		pad_cfg->try_crop.width = fse.max_width;
 		pad_cfg->try_crop.height = fse.max_height;
-- 
2.7.4

[PATCH v1 2/9] media: tegra-video: Enable VI pixel transform for YUV and RGB formats

[Sowjanya Komatineni]

VI Pixel transforms converts source pixel data to selected
destination pixel formats in memory and aligns properly.

YUV and RGB formats need this pixel transform to be enabled.

RAW formats use T_R16_I destination pixel format in memory and
does not need pixel transform as they support direct write to
memory.

So, this patch enables pixel transform for YUV and RGB and keeps
it bypass for RAW formats.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/tegra210.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
index ac066c0..6b23aa7 100644
--- a/drivers/staging/media/tegra-video/tegra210.c
+++ b/drivers/staging/media/tegra-video/tegra210.c
@@ -178,10 +178,23 @@ static int tegra_channel_capture_setup(struct tegra_vi_channel *chan)
 	u32 format = chan->fmtinfo->img_fmt;
 	u32 data_type = chan->fmtinfo->img_dt;
 	u32 word_count = (width * chan->fmtinfo->bit_width) / 8;
+	u32 bypass_pixel_transform = BIT(BYPASS_PXL_TRANSFORM_OFFSET);
+
+	/*
+	 * VI Pixel transformation unit converts source pixels data format
+	 * into selected destination pixel format and aligns properly while
+	 * interfacing with memory packer.
+	 * This pixel transformation should be enabled for YUV and RGB
+	 * formats and should be bypassed for RAW formats as RAW formats
+	 * only support direct to memory.
+	 */
+	if (chan->pg_mode || data_type == TEGRA_IMAGE_DT_YUV422_8 ||
+	    data_type == TEGRA_IMAGE_DT_RGB888)
+		bypass_pixel_transform = 0;
 
 	vi_csi_write(chan, TEGRA_VI_CSI_ERROR_STATUS, 0xffffffff);
 	vi_csi_write(chan, TEGRA_VI_CSI_IMAGE_DEF,
-		     ((chan->pg_mode ? 0 : 1) << BYPASS_PXL_TRANSFORM_OFFSET) |
+		     bypass_pixel_transform |
 		     (format << IMAGE_DEF_FORMAT_OFFSET) |
 		     IMAGE_DEF_DEST_MEM);
 	vi_csi_write(chan, TEGRA_VI_CSI_IMAGE_DT, data_type);
-- 
2.7.4

[PATCH v1 3/9] media: tegra-video: Fix V4L2 pixel format for RGB888_1X24

[Sowjanya Komatineni]

V4L2 pixel format is incorrect for RGB888_1X24.

This patch fixes it.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/tegra210.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
index 6b23aa7..c883925 100644
--- a/drivers/staging/media/tegra-video/tegra210.c
+++ b/drivers/staging/media/tegra-video/tegra210.c
@@ -619,7 +619,7 @@ static const struct tegra_video_format tegra210_video_formats[] = {
 	TEGRA210_VIDEO_FMT(RAW12, 12, SGBRG12_1X12, 2, T_R16_I, SGBRG12),
 	TEGRA210_VIDEO_FMT(RAW12, 12, SBGGR12_1X12, 2, T_R16_I, SBGGR12),
 	/* RGB888 */
-	TEGRA210_VIDEO_FMT(RGB888, 24, RGB888_1X24, 4, T_A8R8G8B8, RGB24),
+	TEGRA210_VIDEO_FMT(RGB888, 24, RGB888_1X24, 4, T_A8R8G8B8, XRGB32),
 	TEGRA210_VIDEO_FMT(RGB888, 24, RGB888_1X32_PADHI, 4, T_A8B8G8R8,
 			   XBGR32),
 	/* YUV422 */
-- 
2.7.4

[PATCH v1 4/9] media: tegra-video: Add support for V4L2_PIX_FMT_NV16

[Sowjanya Komatineni]

NV16 are two-plane versions of YUV422 format.

VI/CSI surface0 registers corresponds to first Y plane and
surface1 registers corresponds to seconds UV plane.

This patch updates image size for NV16 format to include both planes
and programs VI/CSI surface1 registers for UV plane capture.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/tegra210.c | 13 +++++++++++++
 drivers/staging/media/tegra-video/vi.c       |  2 ++
 2 files changed, 15 insertions(+)

diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
index c883925..929d277 100644
--- a/drivers/staging/media/tegra-video/tegra210.c
+++ b/drivers/staging/media/tegra-video/tegra210.c
@@ -287,6 +287,7 @@ static int tegra_channel_capture_frame(struct tegra_vi_channel *chan,
 {
 	u32 thresh, value, frame_start, mw_ack_done;
 	int bytes_per_line = chan->format.bytesperline;
+	u32 sizeimage = chan->format.sizeimage;
 	int err;
 
 	/* program buffer address by using surface 0 */
@@ -296,6 +297,18 @@ static int tegra_channel_capture_frame(struct tegra_vi_channel *chan,
 	vi_csi_write(chan, TEGRA_VI_CSI_SURFACE0_STRIDE, bytes_per_line);
 
 	/*
+	 * Program surface 1 for UV plane with offset sizeimage from Y plane.
+	 */
+	if (chan->fmtinfo->fourcc == V4L2_PIX_FMT_NV16) {
+		vi_csi_write(chan, TEGRA_VI_CSI_SURFACE1_OFFSET_MSB,
+			     ((u64)buf->addr + sizeimage / 2) >> 32);
+		vi_csi_write(chan, TEGRA_VI_CSI_SURFACE1_OFFSET_LSB,
+			     buf->addr + sizeimage / 2);
+		vi_csi_write(chan, TEGRA_VI_CSI_SURFACE1_STRIDE,
+			     bytes_per_line);
+	}
+
+	/*
 	 * Tegra VI block interacts with host1x syncpt for synchronizing
 	 * programmed condition of capture state and hardware operation.
 	 * Frame start and Memory write acknowledge syncpts has their own
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 7edd35c..525c087 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -484,6 +484,8 @@ static void tegra_channel_fmt_align(struct tegra_vi_channel *chan,
 
 	pix->bytesperline = clamp(bpl, min_bpl, max_bpl);
 	pix->sizeimage = pix->bytesperline * pix->height;
+	if (pix->pixelformat == V4L2_PIX_FMT_NV16)
+		pix->sizeimage *= 2;
 }
 
 static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
-- 
2.7.4

[PATCH v1 5/9] media: tegra-video: Add DV timing support

[Sowjanya Komatineni]

This patch adds below v4l2 DV timing ioctls to support HDMI-to-CSI
bridges.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/vi.c | 97 ++++++++++++++++++++++++++++++++++
 1 file changed, 97 insertions(+)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 525c087..d0d84da 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -18,6 +18,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
 
+#include <media/v4l2-dv-timings.h>
 #include <media/v4l2-event.h>
 #include <media/v4l2-fh.h>
 #include <media/v4l2-fwnode.h>
@@ -720,6 +721,97 @@ static int tegra_channel_s_selection(struct file *file, void *fh,
 	return ret;
 }
 
+static int tegra_channel_g_dv_timings(struct file *file, void *fh,
+				      struct v4l2_dv_timings *timings)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+	struct v4l2_subdev *subdev;
+
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	if (!v4l2_subdev_has_op(subdev, video, g_dv_timings))
+		return -ENOTTY;
+
+	return v4l2_device_call_until_err(chan->video.v4l2_dev, 0,
+					  video, g_dv_timings, timings);
+}
+
+static int tegra_channel_s_dv_timings(struct file *file, void *fh,
+				      struct v4l2_dv_timings *timings)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+	struct v4l2_subdev *subdev;
+	struct v4l2_bt_timings *bt = &timings->bt;
+	struct v4l2_dv_timings curr_timings;
+	int ret;
+
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	if (!v4l2_subdev_has_op(subdev, video, s_dv_timings))
+		return -ENOTTY;
+
+	ret = tegra_channel_g_dv_timings(file, fh, &curr_timings);
+	if (ret)
+		return ret;
+
+	if (v4l2_match_dv_timings(timings, &curr_timings, 0, false))
+		return 0;
+
+	if (vb2_is_busy(&chan->queue))
+		return -EBUSY;
+
+	ret = v4l2_device_call_until_err(chan->video.v4l2_dev, 0,
+					 video, s_dv_timings, timings);
+	if (ret)
+		return ret;
+
+	chan->format.width = bt->width;
+	chan->format.height = bt->height;
+	chan->format.bytesperline = bt->width * chan->fmtinfo->bpp;
+	chan->format.sizeimage = chan->format.bytesperline * bt->height;
+	tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
+
+	return 0;
+}
+
+static int tegra_channel_query_dv_timings(struct file *file, void *fh,
+					  struct v4l2_dv_timings *timings)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+	struct v4l2_subdev *subdev;
+
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	if (!v4l2_subdev_has_op(subdev, video, query_dv_timings))
+		return -ENOTTY;
+
+	return v4l2_device_call_until_err(chan->video.v4l2_dev, 0,
+					  video, query_dv_timings, timings);
+}
+
+static int tegra_channel_enum_dv_timings(struct file *file, void *fh,
+					 struct v4l2_enum_dv_timings *timings)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+	struct v4l2_subdev *subdev;
+
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	if (!v4l2_subdev_has_op(subdev, pad, enum_dv_timings))
+		return -ENOTTY;
+
+	return v4l2_subdev_call(subdev, pad, enum_dv_timings, timings);
+}
+
+static int tegra_channel_dv_timings_cap(struct file *file, void *fh,
+					struct v4l2_dv_timings_cap *cap)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+	struct v4l2_subdev *subdev;
+
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	if (!v4l2_subdev_has_op(subdev, pad, dv_timings_cap))
+		return -ENOTTY;
+
+	return v4l2_subdev_call(subdev, pad, dv_timings_cap, cap);
+}
+
 static int tegra_channel_enum_input(struct file *file, void *fh,
 				    struct v4l2_input *inp)
 {
@@ -779,6 +871,11 @@ static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {
 	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
 	.vidioc_g_selection		= tegra_channel_g_selection,
 	.vidioc_s_selection		= tegra_channel_s_selection,
+	.vidioc_g_dv_timings		= tegra_channel_g_dv_timings,
+	.vidioc_s_dv_timings		= tegra_channel_s_dv_timings,
+	.vidioc_query_dv_timings	= tegra_channel_query_dv_timings,
+	.vidioc_enum_dv_timings		= tegra_channel_enum_dv_timings,
+	.vidioc_dv_timings_cap		= tegra_channel_dv_timings_cap,
 };
 
 /*
-- 
2.7.4

[PATCH v1 6/9] media: tegra-video: Add support for EDID ioctl ops

[Sowjanya Komatineni]

This patch adds support for EDID get and set v4l2 ioctl ops to use
with HDMI to CSI bridges.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/vi.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index d0d84da..92f36b1 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -721,6 +721,32 @@ static int tegra_channel_s_selection(struct file *file, void *fh,
 	return ret;
 }
 
+static int tegra_channel_g_edid(struct file *file, void *fh,
+				struct v4l2_edid *edid)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+	struct v4l2_subdev *subdev;
+
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	if (!v4l2_subdev_has_op(subdev, pad, get_edid))
+		return -ENOTTY;
+
+	return v4l2_subdev_call(subdev, pad, get_edid, edid);
+}
+
+static int tegra_channel_s_edid(struct file *file, void *fh,
+				struct v4l2_edid *edid)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+	struct v4l2_subdev *subdev;
+
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	if (!v4l2_subdev_has_op(subdev, pad, set_edid))
+		return -ENOTTY;
+
+	return v4l2_subdev_call(subdev, pad, set_edid, edid);
+}
+
 static int tegra_channel_g_dv_timings(struct file *file, void *fh,
 				      struct v4l2_dv_timings *timings)
 {
@@ -871,6 +897,8 @@ static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {
 	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
 	.vidioc_g_selection		= tegra_channel_g_selection,
 	.vidioc_s_selection		= tegra_channel_s_selection,
+	.vidioc_g_edid			= tegra_channel_g_edid,
+	.vidioc_s_edid			= tegra_channel_s_edid,
 	.vidioc_g_dv_timings		= tegra_channel_g_dv_timings,
 	.vidioc_s_dv_timings		= tegra_channel_s_dv_timings,
 	.vidioc_query_dv_timings	= tegra_channel_query_dv_timings,
-- 
2.7.4

[PATCH v1 7/9] media: tegra-video: Add support for VIDIOC_LOG_STATUS ioctl

[Sowjanya Komatineni]

This patch adds support for log_status ioctl.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/vi.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 92f36b1..936e5e5 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -838,6 +838,15 @@ static int tegra_channel_dv_timings_cap(struct file *file, void *fh,
 	return v4l2_subdev_call(subdev, pad, dv_timings_cap, cap);
 }
 
+static int tegra_channel_log_status(struct file *file, void *fh)
+{
+	struct tegra_vi_channel *chan = video_drvdata(file);
+
+	v4l2_device_call_all(chan->video.v4l2_dev, 0, core, log_status);
+
+	return 0;
+}
+
 static int tegra_channel_enum_input(struct file *file, void *fh,
 				    struct v4l2_input *inp)
 {
@@ -904,6 +913,7 @@ static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {
 	.vidioc_query_dv_timings	= tegra_channel_query_dv_timings,
 	.vidioc_enum_dv_timings		= tegra_channel_enum_dv_timings,
 	.vidioc_dv_timings_cap		= tegra_channel_dv_timings_cap,
+	.vidioc_log_status		= tegra_channel_log_status,
 };
 
 /*
-- 
2.7.4

[PATCH v1 8/9] media: tegra-video: Add support for V4L2_EVENT_SOURCE_CHANGE

[Sowjanya Komatineni]

Current implementation uses v4l2_ctrl_subscribe_event() and this
does not handle V4L2_EVENT_SOURCE_CHANGE.

So, update driver to handle V4L2_EVENT_SOURCE_CHANGE.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/vi.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 936e5e5..28c06a9 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -642,6 +642,18 @@ static int tegra_channel_set_subdev_active_fmt(struct tegra_vi_channel *chan)
 	return 0;
 }
 
+static int
+tegra_channel_subscribe_event(struct v4l2_fh *fh,
+			      const struct v4l2_event_subscription *sub)
+{
+	switch (sub->type) {
+	case V4L2_EVENT_SOURCE_CHANGE:
+		return v4l2_event_subscribe(fh, sub, 4, NULL);
+	}
+
+	return v4l2_ctrl_subscribe_event(fh, sub);
+}
+
 static int tegra_channel_g_selection(struct file *file, void *priv,
 				     struct v4l2_selection *sel)
 {
@@ -902,7 +914,7 @@ static const struct v4l2_ioctl_ops tegra_channel_ioctl_ops = {
 	.vidioc_expbuf			= vb2_ioctl_expbuf,
 	.vidioc_streamon		= vb2_ioctl_streamon,
 	.vidioc_streamoff		= vb2_ioctl_streamoff,
-	.vidioc_subscribe_event		= v4l2_ctrl_subscribe_event,
+	.vidioc_subscribe_event		= tegra_channel_subscribe_event,
 	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
 	.vidioc_g_selection		= tegra_channel_g_selection,
 	.vidioc_s_selection		= tegra_channel_s_selection,
-- 
2.7.4

[PATCH v1 9/9] media: tegra-video: Implement V4L2 device notify callback

[Sowjanya Komatineni]

Implement V4L2 device notify callback to handle
V4L2_EVENT_SOURCE_CHANGE event from subdevices.

HDMI-to-CSI bridge drivers trigger V4L2_EVENT_SOURCE_CHANGE when
source DV timing changes are detected or when HDMI hotplug happens.

Runtime source parameter changes during active streaming is not
allowed and Tegra video driver calls vb2_queue_error to signal a
fatal error if a notification of this event happens during an active
streaming.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/staging/media/tegra-video/vi.c    |  3 +++
 drivers/staging/media/tegra-video/video.c | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 28c06a9..e866f7d 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -1634,6 +1634,9 @@ static int tegra_vi_graph_notify_complete(struct v4l2_async_notifier *notifier)
 
 	v4l2_set_subdev_hostdata(subdev, chan);
 
+	subdev = tegra_channel_get_remote_source_subdev(chan);
+	v4l2_set_subdev_hostdata(subdev, chan);
+
 	return 0;
 
 unregister_video:
diff --git a/drivers/staging/media/tegra-video/video.c b/drivers/staging/media/tegra-video/video.c
index e50bd70..d966b31 100644
--- a/drivers/staging/media/tegra-video/video.c
+++ b/drivers/staging/media/tegra-video/video.c
@@ -7,6 +7,8 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 
+#include <media/v4l2-event.h>
+
 #include "video.h"
 
 static void tegra_v4l2_dev_release(struct v4l2_device *v4l2_dev)
@@ -24,6 +26,21 @@ static void tegra_v4l2_dev_release(struct v4l2_device *v4l2_dev)
 	kfree(vid);
 }
 
+static void tegra_v4l2_dev_notify(struct v4l2_subdev *sd,
+				  unsigned int notification, void *arg)
+{
+	struct tegra_vi_channel *chan;
+	const struct v4l2_event *ev = arg;
+
+	if (notification != V4L2_DEVICE_NOTIFY_EVENT)
+		return;
+
+	chan = v4l2_get_subdev_hostdata(sd);
+	v4l2_event_queue(&chan->video, arg);
+	if (ev->type == V4L2_EVENT_SOURCE_CHANGE && vb2_is_streaming(&chan->queue))
+		vb2_queue_error(&chan->queue);
+}
+
 static int host1x_video_probe(struct host1x_device *dev)
 {
 	struct tegra_video_device *vid;
@@ -49,6 +66,7 @@ static int host1x_video_probe(struct host1x_device *dev)
 
 	vid->v4l2_dev.mdev = &vid->media_dev;
 	vid->v4l2_dev.release = tegra_v4l2_dev_release;
+	vid->v4l2_dev.notify = tegra_v4l2_dev_notify;
 	ret = v4l2_device_register(&dev->dev, &vid->v4l2_dev);
 	if (ret < 0) {
 		dev_err(&dev->dev,
-- 
2.7.4