| Message ID | 20230407133852.2850145-15-luca.ceresoli@bootlin.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add Tegra20 parallel video input capture | expand |
Hi Luca, I just encountered an error in this patch, so I have rejected the PR I made. See below for the details: On 07/04/2023 15:38, Luca Ceresoli wrote: > The CSI module does not handle all the MIPI lane calibration procedure, > leaving a small part of it to the VI module. In doing this, > tegra_channel_enable_stream() (vi.c) manipulates the private data of the > upstream subdev casting it to struct 'tegra_csi_channel', which will be > wrong after introducing a VIP (parallel video input) channel. > > This prevents adding support for the VIP module. It also breaks the > logical isolation between modules. > > Since the lane calibration requirement does not exist in the parallel input > module, moving the calibration function to a per-module op is not > optimal. Instead move the calibration procedure in the CSI module, together > with the rest of the calibration procedures. After this change, > tegra_channel_enable_stream() just calls v4l2_subdev_call() to ask for a > stream start/stop to the CSI module, which in turn knows all the > CSI-specific details to implement it. > > Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com> > Reviewed-by: Dmitry Osipenko <digetx@gmail.com> > > --- > > No changes in v5 > > Changed in v4: > - Added review tags > > No changes in v3 > No changes in v2 > --- > drivers/staging/media/tegra-video/csi.c | 44 ++++++++++++++++++++ > drivers/staging/media/tegra-video/vi.c | 54 ++----------------------- > 2 files changed, 48 insertions(+), 50 deletions(-) > > diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c > index 9a03d5ccdf3c..b93fc879ef3a 100644 > --- a/drivers/staging/media/tegra-video/csi.c > +++ b/drivers/staging/media/tegra-video/csi.c > @@ -328,12 +328,42 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev) > } > > csi_chan->pg_mode = chan->pg_mode; > + > + /* > + * Tegra CSI receiver can detect the first LP to HS transition. > + * So, start the CSI stream-on prior to sensor stream-on and > + * vice-versa for stream-off. > + */ > ret = csi->ops->csi_start_streaming(csi_chan); > if (ret < 0) > goto finish_calibration; > > + if (csi_chan->mipi) { > + struct v4l2_subdev *src_subdev; > + /* > + * TRM has incorrectly documented to wait for done status from > + * calibration logic after CSI interface power on. > + * As per the design, calibration results are latched and applied > + * to the pads only when the link is in LP11 state which will happen > + * during the sensor stream-on. > + * CSI subdev stream-on triggers start of MIPI pads calibration. > + * Wait for calibration to finish here after sensor subdev stream-on. > + */ > + src_subdev = tegra_channel_get_remote_source_subdev(chan); > + ret = v4l2_subdev_call(src_subdev, video, s_stream, true); > + err = tegra_mipi_finish_calibration(csi_chan->mipi); > + > + if (ret < 0 && ret != -ENOIOCTLCMD) > + goto disable_csi_stream; If there was an error from s_stream, then tegra_mipi_finish_calibration is called and it goes to disable_csi_stream... > + > + if (err < 0) > + dev_warn(csi->dev, "MIPI calibration failed: %d\n", err); > + } > + > return 0; > > +disable_csi_stream: > + csi->ops->csi_stop_streaming(csi_chan); > finish_calibration: > if (csi_chan->mipi) > tegra_mipi_finish_calibration(csi_chan->mipi); ...but here tegra_mipi_finish_calibration() is called again, leading to an unlock imbalance. This is the callstack: [ 109.894502] IMX274 5-001a: s_stream failed [ 109.900203] ===================================== [ 109.904898] WARNING: bad unlock balance detected! [ 109.909594] 6.3.0-rc2-tegra #16 Not tainted [ 109.913774] ------------------------------------- [ 109.918470] v4l2-ctl/2000 is trying to release lock (&mipi->lock) at: [ 109.924911] [<ffff80000866b828>] tegra_mipi_finish_calibration+0x84/0xb0 [ 109.931621] but there are no more locks to release! [ 109.936489] other info that might help us debug this: [ 109.943004] 1 lock held by v4l2-ctl/2000: [ 109.947009] #0: ffff000083bcf6a8 (&chan->video_lock){....}-{3:3}, at: __video_do_ioctl+0xdc/0x3c8 [ 109.955987] stack backtrace: [ 109.960336] CPU: 2 PID: 2000 Comm: v4l2-ctl Not tainted 6.3.0-rc2-tegra #16 [ 109.967290] Hardware name: NVIDIA Jetson TX1 Developer Kit (DT) [ 109.973200] Call trace: [ 109.975642] dump_backtrace+0xa0/0xfc [ 109.979308] show_stack+0x18/0x24 [ 109.982622] dump_stack_lvl+0x48/0x60 [ 109.986285] dump_stack+0x18/0x24 [ 109.989598] print_unlock_imbalance_bug+0x130/0x148 [ 109.994472] lock_release+0x1bc/0x248 [ 109.998131] __mutex_unlock_slowpath+0x48/0x2cc [ 110.002657] mutex_unlock+0x20/0x2c [ 110.006141] tegra_mipi_finish_calibration+0x84/0xb0 [ 110.011102] tegra_csi_s_stream+0x260/0x318 [ 110.015286] call_s_stream+0x80/0xcc [ 110.018857] tegra_channel_set_stream+0x58/0xe4 [ 110.023386] tegra210_vi_start_streaming+0xb0/0x1c8 [ 110.028262] tegra_channel_start_streaming+0x54/0x134 [ 110.033311] vb2_start_streaming+0xbc/0x1b8 [ 110.037491] vb2_core_streamon+0x158/0x260 [ 110.041582] vb2_ioctl_streamon+0x4c/0x90 [ 110.045589] v4l_streamon+0x24/0x30 [ 110.049076] __video_do_ioctl+0x160/0x3c8 [ 110.053082] video_usercopy+0x1f0/0x658 [ 110.056916] video_ioctl2+0x18/0x28 [ 110.060404] v4l2_ioctl+0x40/0x60 [ 110.063715] __arm64_sys_ioctl+0xac/0xf0 [ 110.067638] invoke_syscall+0x48/0x114 [ 110.071385] el0_svc_common.constprop.0+0x44/0xec [ 110.076086] do_el0_svc+0x38/0x98 [ 110.079398] el0_svc+0x2c/0x84 [ 110.082454] el0t_64_sync_handler+0xf4/0x120 [ 110.086722] el0t_64_sync+0x190/0x194 Regards, Hans > @@ -352,10 +382,24 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev) > > static int tegra_csi_disable_stream(struct v4l2_subdev *subdev) > { > + struct tegra_vi_channel *chan = v4l2_get_subdev_hostdata(subdev); > struct tegra_csi_channel *csi_chan = to_csi_chan(subdev); > struct tegra_csi *csi = csi_chan->csi; > int err; > > + /* > + * Stream-off subdevices in reverse order to stream-on. > + * Remote source subdev in TPG mode is same as CSI subdev. > + */ > + if (csi_chan->mipi) { > + struct v4l2_subdev *src_subdev; > + > + src_subdev = tegra_channel_get_remote_source_subdev(chan); > + err = v4l2_subdev_call(src_subdev, video, s_stream, false); > + if (err < 0 && err != -ENOIOCTLCMD) > + dev_err_probe(csi->dev, err, "source subdev stream off failed\n"); > + } > + > csi->ops->csi_stop_streaming(csi_chan); > > if (csi_chan->mipi) { > diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c > index b88532d8d2c9..c76c2a404889 100644 > --- a/drivers/staging/media/tegra-video/vi.c > +++ b/drivers/staging/media/tegra-video/vi.c > @@ -197,49 +197,15 @@ tegra_channel_get_remote_source_subdev(struct tegra_vi_channel *chan) > > static int tegra_channel_enable_stream(struct tegra_vi_channel *chan) > { > - struct v4l2_subdev *csi_subdev, *src_subdev; > - struct tegra_csi_channel *csi_chan; > - int ret, err; > + struct v4l2_subdev *subdev; > + int ret; > > - /* > - * Tegra CSI receiver can detect the first LP to HS transition. > - * So, start the CSI stream-on prior to sensor stream-on and > - * vice-versa for stream-off. > - */ > - csi_subdev = tegra_channel_get_remote_csi_subdev(chan); > - ret = v4l2_subdev_call(csi_subdev, video, s_stream, true); > + subdev = tegra_channel_get_remote_csi_subdev(chan); > + ret = v4l2_subdev_call(subdev, video, s_stream, true); > if (ret < 0 && ret != -ENOIOCTLCMD) > return ret; > > - if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)) > - return 0; > - > - csi_chan = v4l2_get_subdevdata(csi_subdev); > - /* > - * TRM has incorrectly documented to wait for done status from > - * calibration logic after CSI interface power on. > - * As per the design, calibration results are latched and applied > - * to the pads only when the link is in LP11 state which will happen > - * during the sensor stream-on. > - * CSI subdev stream-on triggers start of MIPI pads calibration. > - * Wait for calibration to finish here after sensor subdev stream-on. > - */ > - src_subdev = tegra_channel_get_remote_source_subdev(chan); > - ret = v4l2_subdev_call(src_subdev, video, s_stream, true); > - err = tegra_mipi_finish_calibration(csi_chan->mipi); > - > - if (ret < 0 && ret != -ENOIOCTLCMD) > - goto err_disable_csi_stream; > - > - if (err < 0) > - dev_warn(csi_chan->csi->dev, > - "MIPI calibration failed: %d\n", err); > - > return 0; > - > -err_disable_csi_stream: > - v4l2_subdev_call(csi_subdev, video, s_stream, false); > - return ret; > } > > static int tegra_channel_disable_stream(struct tegra_vi_channel *chan) > @@ -247,18 +213,6 @@ static int tegra_channel_disable_stream(struct tegra_vi_channel *chan) > struct v4l2_subdev *subdev; > int ret; > > - /* > - * Stream-off subdevices in reverse order to stream-on. > - * Remote source subdev in TPG mode is same as CSI subdev. > - */ > - subdev = tegra_channel_get_remote_source_subdev(chan); > - ret = v4l2_subdev_call(subdev, video, s_stream, false); > - if (ret < 0 && ret != -ENOIOCTLCMD) > - return ret; > - > - if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)) > - return 0; > - > subdev = tegra_channel_get_remote_csi_subdev(chan); > ret = v4l2_subdev_call(subdev, video, s_stream, false); > if (ret < 0 && ret != -ENOIOCTLCMD)
Hi Hans, On Fri, 14 Apr 2023 17:51:34 +0200 Hans Verkuil <hverkuil-cisco@xs4all.nl> wrote: > Hi Luca, > > I just encountered an error in this patch, so I have rejected the PR I made. > > See below for the details: > > On 07/04/2023 15:38, Luca Ceresoli wrote: > > The CSI module does not handle all the MIPI lane calibration procedure, > > leaving a small part of it to the VI module. In doing this, > > tegra_channel_enable_stream() (vi.c) manipulates the private data of the > > upstream subdev casting it to struct 'tegra_csi_channel', which will be > > wrong after introducing a VIP (parallel video input) channel. > > > > This prevents adding support for the VIP module. It also breaks the > > logical isolation between modules. > > > > Since the lane calibration requirement does not exist in the parallel input > > module, moving the calibration function to a per-module op is not > > optimal. Instead move the calibration procedure in the CSI module, together > > with the rest of the calibration procedures. After this change, > > tegra_channel_enable_stream() just calls v4l2_subdev_call() to ask for a > > stream start/stop to the CSI module, which in turn knows all the > > CSI-specific details to implement it. > > > > Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com> > > Reviewed-by: Dmitry Osipenko <digetx@gmail.com> > > > > --- > > > > No changes in v5 > > > > Changed in v4: > > - Added review tags > > > > No changes in v3 > > No changes in v2 > > --- > > drivers/staging/media/tegra-video/csi.c | 44 ++++++++++++++++++++ > > drivers/staging/media/tegra-video/vi.c | 54 ++----------------------- > > 2 files changed, 48 insertions(+), 50 deletions(-) > > > > diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c > > index 9a03d5ccdf3c..b93fc879ef3a 100644 > > --- a/drivers/staging/media/tegra-video/csi.c > > +++ b/drivers/staging/media/tegra-video/csi.c > > @@ -328,12 +328,42 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev) > > } > > > > csi_chan->pg_mode = chan->pg_mode; > > + > > + /* > > + * Tegra CSI receiver can detect the first LP to HS transition. > > + * So, start the CSI stream-on prior to sensor stream-on and > > + * vice-versa for stream-off. > > + */ > > ret = csi->ops->csi_start_streaming(csi_chan); > > if (ret < 0) > > goto finish_calibration; > > > > + if (csi_chan->mipi) { > > + struct v4l2_subdev *src_subdev; > > + /* > > + * TRM has incorrectly documented to wait for done status from > > + * calibration logic after CSI interface power on. > > + * As per the design, calibration results are latched and applied > > + * to the pads only when the link is in LP11 state which will happen > > + * during the sensor stream-on. > > + * CSI subdev stream-on triggers start of MIPI pads calibration. > > + * Wait for calibration to finish here after sensor subdev stream-on. > > + */ > > + src_subdev = tegra_channel_get_remote_source_subdev(chan); > > + ret = v4l2_subdev_call(src_subdev, video, s_stream, true); > > + err = tegra_mipi_finish_calibration(csi_chan->mipi); > > + > > + if (ret < 0 && ret != -ENOIOCTLCMD) > > + goto disable_csi_stream; > > If there was an error from s_stream, then tegra_mipi_finish_calibration is called > and it goes to disable_csi_stream... > > > + > > + if (err < 0) > > + dev_warn(csi->dev, "MIPI calibration failed: %d\n", err); > > + } > > + > > return 0; > > > > +disable_csi_stream: > > + csi->ops->csi_stop_streaming(csi_chan); > > finish_calibration: > > if (csi_chan->mipi) > > tegra_mipi_finish_calibration(csi_chan->mipi); > > ...but here tegra_mipi_finish_calibration() is called again, leading to an unlock > imbalance. Many thanks for your testing! Unfortunately I have no Tegra210 hardware so this never happened here, but with your report the problem got obvious and, luckily, the fix appeared to be just a oneliner. v6 just sent! I'm wondering whether there is still hope to get this 6.4... Best regards, Luca
On 18/04/2023 10:07, Luca Ceresoli wrote: > Hi Hans, > > On Fri, 14 Apr 2023 17:51:34 +0200 > Hans Verkuil <hverkuil-cisco@xs4all.nl> wrote: > >> Hi Luca, >> >> I just encountered an error in this patch, so I have rejected the PR I made. >> >> See below for the details: >> >> On 07/04/2023 15:38, Luca Ceresoli wrote: >>> The CSI module does not handle all the MIPI lane calibration procedure, >>> leaving a small part of it to the VI module. In doing this, >>> tegra_channel_enable_stream() (vi.c) manipulates the private data of the >>> upstream subdev casting it to struct 'tegra_csi_channel', which will be >>> wrong after introducing a VIP (parallel video input) channel. >>> >>> This prevents adding support for the VIP module. It also breaks the >>> logical isolation between modules. >>> >>> Since the lane calibration requirement does not exist in the parallel input >>> module, moving the calibration function to a per-module op is not >>> optimal. Instead move the calibration procedure in the CSI module, together >>> with the rest of the calibration procedures. After this change, >>> tegra_channel_enable_stream() just calls v4l2_subdev_call() to ask for a >>> stream start/stop to the CSI module, which in turn knows all the >>> CSI-specific details to implement it. >>> >>> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com> >>> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> >>> >>> --- >>> >>> No changes in v5 >>> >>> Changed in v4: >>> - Added review tags >>> >>> No changes in v3 >>> No changes in v2 >>> --- >>> drivers/staging/media/tegra-video/csi.c | 44 ++++++++++++++++++++ >>> drivers/staging/media/tegra-video/vi.c | 54 ++----------------------- >>> 2 files changed, 48 insertions(+), 50 deletions(-) >>> >>> diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c >>> index 9a03d5ccdf3c..b93fc879ef3a 100644 >>> --- a/drivers/staging/media/tegra-video/csi.c >>> +++ b/drivers/staging/media/tegra-video/csi.c >>> @@ -328,12 +328,42 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev) >>> } >>> >>> csi_chan->pg_mode = chan->pg_mode; >>> + >>> + /* >>> + * Tegra CSI receiver can detect the first LP to HS transition. >>> + * So, start the CSI stream-on prior to sensor stream-on and >>> + * vice-versa for stream-off. >>> + */ >>> ret = csi->ops->csi_start_streaming(csi_chan); >>> if (ret < 0) >>> goto finish_calibration; >>> >>> + if (csi_chan->mipi) { >>> + struct v4l2_subdev *src_subdev; >>> + /* >>> + * TRM has incorrectly documented to wait for done status from >>> + * calibration logic after CSI interface power on. >>> + * As per the design, calibration results are latched and applied >>> + * to the pads only when the link is in LP11 state which will happen >>> + * during the sensor stream-on. >>> + * CSI subdev stream-on triggers start of MIPI pads calibration. >>> + * Wait for calibration to finish here after sensor subdev stream-on. >>> + */ >>> + src_subdev = tegra_channel_get_remote_source_subdev(chan); >>> + ret = v4l2_subdev_call(src_subdev, video, s_stream, true); >>> + err = tegra_mipi_finish_calibration(csi_chan->mipi); >>> + >>> + if (ret < 0 && ret != -ENOIOCTLCMD) >>> + goto disable_csi_stream; >> >> If there was an error from s_stream, then tegra_mipi_finish_calibration is called >> and it goes to disable_csi_stream... >> >>> + >>> + if (err < 0) >>> + dev_warn(csi->dev, "MIPI calibration failed: %d\n", err); >>> + } >>> + >>> return 0; >>> >>> +disable_csi_stream: >>> + csi->ops->csi_stop_streaming(csi_chan); >>> finish_calibration: >>> if (csi_chan->mipi) >>> tegra_mipi_finish_calibration(csi_chan->mipi); >> >> ...but here tegra_mipi_finish_calibration() is called again, leading to an unlock >> imbalance. > > Many thanks for your testing! Unfortunately I have no Tegra210 hardware > so this never happened here, but with your report the problem got > obvious and, luckily, the fix appeared to be just a oneliner. > > v6 just sent! I'm wondering whether there is still hope to get this > 6.4... Sorry, it's too late for 6.4 now. Only fixes can go in for 6.4. Regards, Hans > > Best regards, > Luca >
diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c index 9a03d5ccdf3c..b93fc879ef3a 100644 --- a/drivers/staging/media/tegra-video/csi.c +++ b/drivers/staging/media/tegra-video/csi.c @@ -328,12 +328,42 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev) } csi_chan->pg_mode = chan->pg_mode; + + /* + * Tegra CSI receiver can detect the first LP to HS transition. + * So, start the CSI stream-on prior to sensor stream-on and + * vice-versa for stream-off. + */ ret = csi->ops->csi_start_streaming(csi_chan); if (ret < 0) goto finish_calibration; + if (csi_chan->mipi) { + struct v4l2_subdev *src_subdev; + /* + * TRM has incorrectly documented to wait for done status from + * calibration logic after CSI interface power on. + * As per the design, calibration results are latched and applied + * to the pads only when the link is in LP11 state which will happen + * during the sensor stream-on. + * CSI subdev stream-on triggers start of MIPI pads calibration. + * Wait for calibration to finish here after sensor subdev stream-on. + */ + src_subdev = tegra_channel_get_remote_source_subdev(chan); + ret = v4l2_subdev_call(src_subdev, video, s_stream, true); + err = tegra_mipi_finish_calibration(csi_chan->mipi); + + if (ret < 0 && ret != -ENOIOCTLCMD) + goto disable_csi_stream; + + if (err < 0) + dev_warn(csi->dev, "MIPI calibration failed: %d\n", err); + } + return 0; +disable_csi_stream: + csi->ops->csi_stop_streaming(csi_chan); finish_calibration: if (csi_chan->mipi) tegra_mipi_finish_calibration(csi_chan->mipi); @@ -352,10 +382,24 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev) static int tegra_csi_disable_stream(struct v4l2_subdev *subdev) { + struct tegra_vi_channel *chan = v4l2_get_subdev_hostdata(subdev); struct tegra_csi_channel *csi_chan = to_csi_chan(subdev); struct tegra_csi *csi = csi_chan->csi; int err; + /* + * Stream-off subdevices in reverse order to stream-on. + * Remote source subdev in TPG mode is same as CSI subdev. + */ + if (csi_chan->mipi) { + struct v4l2_subdev *src_subdev; + + src_subdev = tegra_channel_get_remote_source_subdev(chan); + err = v4l2_subdev_call(src_subdev, video, s_stream, false); + if (err < 0 && err != -ENOIOCTLCMD) + dev_err_probe(csi->dev, err, "source subdev stream off failed\n"); + } + csi->ops->csi_stop_streaming(csi_chan); if (csi_chan->mipi) { diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c index b88532d8d2c9..c76c2a404889 100644 --- a/drivers/staging/media/tegra-video/vi.c +++ b/drivers/staging/media/tegra-video/vi.c @@ -197,49 +197,15 @@ tegra_channel_get_remote_source_subdev(struct tegra_vi_channel *chan) static int tegra_channel_enable_stream(struct tegra_vi_channel *chan) { - struct v4l2_subdev *csi_subdev, *src_subdev; - struct tegra_csi_channel *csi_chan; - int ret, err; + struct v4l2_subdev *subdev; + int ret; - /* - * Tegra CSI receiver can detect the first LP to HS transition. - * So, start the CSI stream-on prior to sensor stream-on and - * vice-versa for stream-off. - */ - csi_subdev = tegra_channel_get_remote_csi_subdev(chan); - ret = v4l2_subdev_call(csi_subdev, video, s_stream, true); + subdev = tegra_channel_get_remote_csi_subdev(chan); + ret = v4l2_subdev_call(subdev, video, s_stream, true); if (ret < 0 && ret != -ENOIOCTLCMD) return ret; - if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)) - return 0; - - csi_chan = v4l2_get_subdevdata(csi_subdev); - /* - * TRM has incorrectly documented to wait for done status from - * calibration logic after CSI interface power on. - * As per the design, calibration results are latched and applied - * to the pads only when the link is in LP11 state which will happen - * during the sensor stream-on. - * CSI subdev stream-on triggers start of MIPI pads calibration. - * Wait for calibration to finish here after sensor subdev stream-on. - */ - src_subdev = tegra_channel_get_remote_source_subdev(chan); - ret = v4l2_subdev_call(src_subdev, video, s_stream, true); - err = tegra_mipi_finish_calibration(csi_chan->mipi); - - if (ret < 0 && ret != -ENOIOCTLCMD) - goto err_disable_csi_stream; - - if (err < 0) - dev_warn(csi_chan->csi->dev, - "MIPI calibration failed: %d\n", err); - return 0; - -err_disable_csi_stream: - v4l2_subdev_call(csi_subdev, video, s_stream, false); - return ret; } static int tegra_channel_disable_stream(struct tegra_vi_channel *chan) @@ -247,18 +213,6 @@ static int tegra_channel_disable_stream(struct tegra_vi_channel *chan) struct v4l2_subdev *subdev; int ret; - /* - * Stream-off subdevices in reverse order to stream-on. - * Remote source subdev in TPG mode is same as CSI subdev. - */ - subdev = tegra_channel_get_remote_source_subdev(chan); - ret = v4l2_subdev_call(subdev, video, s_stream, false); - if (ret < 0 && ret != -ENOIOCTLCMD) - return ret; - - if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)) - return 0; - subdev = tegra_channel_get_remote_csi_subdev(chan); ret = v4l2_subdev_call(subdev, video, s_stream, false); if (ret < 0 && ret != -ENOIOCTLCMD)