| Message ID | 20240820195016.16028-4-hdegoede@redhat.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series |
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| Related | show |
Hi Hans, Thanks for the patch. Actually in mtkisp7, we did something very similar [1]. (And I just caught a bug by checking your changes. Thanks :) [1]: https://chromium-review.googlesource.com/c/chromiumos/third_party/libcamera/+/5525900 On Tue, Aug 20, 2024 at 9:50 PM Hans de Goede <hdegoede@redhat.com> wrote: > ATM libcamera always keeps all /dev/video# and /dev/v4l2_subdev# nodes > for a pipeline open after enumerating the camera. > > This is a problem for uvcvideo and atomisp /dev/video# nodes as well as > for VCM /dev/v4l2_subdev# nodes. Keeping these open stops the underlying > hw-devices from being able to enter runtime-suspend causing significant > unnecessary power-usage. > > Add a stub acquireDevice() method to the PipelineHandler class which > pipeline handlers can override to delay opening /dev nodes until > the camera is acquired. > > Note pipeline handlers typically also will need access to /dev nodes > for their CameraConfig::validate() implementation for tryFormat() calls. > Making sure that /dev nodes are opened as necessary from validate() is > left up to the pipeline handler implementation. > > Signed-off-by: Hans de Goede <hdegoede@redhat.com> > --- > include/libcamera/internal/pipeline_handler.h | 3 +- > src/libcamera/camera.cpp | 2 +- > src/libcamera/pipeline_handler.cpp | 43 +++++++++++++++---- > 3 files changed, 37 insertions(+), 11 deletions(-) > > diff --git a/include/libcamera/internal/pipeline_handler.h > b/include/libcamera/internal/pipeline_handler.h > index cad5812f..597f7c3e 100644 > --- a/include/libcamera/internal/pipeline_handler.h > +++ b/include/libcamera/internal/pipeline_handler.h > @@ -45,7 +45,7 @@ public: > MediaDevice *acquireMediaDevice(DeviceEnumerator *enumerator, > const DeviceMatch &dm); > > - bool acquire(); > + bool acquire(Camera *camera); > void release(Camera *camera); > > virtual std::unique_ptr<CameraConfiguration> > generateConfiguration(Camera *camera, > @@ -79,6 +79,7 @@ protected: > virtual int queueRequestDevice(Camera *camera, Request *request) = > 0; > virtual void stopDevice(Camera *camera) = 0; > > + virtual bool acquireDevice(Camera *camera); > virtual void releaseDevice(Camera *camera); > > CameraManager *manager_; > diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp > index 382a68f7..4e393f89 100644 > --- a/src/libcamera/camera.cpp > +++ b/src/libcamera/camera.cpp > @@ -995,7 +995,7 @@ int Camera::acquire() > if (ret < 0) > return ret == -EACCES ? -EBUSY : ret; > > - if (!d->pipe_->acquire()) { > + if (!d->pipe_->acquire(this)) { > LOG(Camera, Info) > << "Pipeline handler in use by another process"; > return -EBUSY; > diff --git a/src/libcamera/pipeline_handler.cpp > b/src/libcamera/pipeline_handler.cpp > index 1fc22d6a..e1342306 100644 > --- a/src/libcamera/pipeline_handler.cpp > +++ b/src/libcamera/pipeline_handler.cpp > @@ -163,20 +163,22 @@ MediaDevice > *PipelineHandler::acquireMediaDevice(DeviceEnumerator *enumerator, > * has already acquired it > * \sa release() > */ > -bool PipelineHandler::acquire() > +bool PipelineHandler::acquire(Camera *camera) > { > MutexLocker locker(lock_); > > - if (useCount_) { > - ++useCount_; > - return true; > + if (useCount_ == 0) { > + for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { > + if (!media->lock()) { > + unlockMediaDevices(); > + return false; > + } > + } > } > > - for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { > - if (!media->lock()) { > - unlockMediaDevices(); > - return false; > - } > + if (!acquireDevice(camera)) { > + unlockMediaDevices(); > I think we should only unlock media devices if it's the first acquire being called, as there might be other ongoing usages on other cameras [2]. Therefore: ``` if (useCount_ == 0) unlockMediaDevices(); ``` [2]: https://chromium-review.googlesource.com/c/chromiumos/third_party/libcamera/+/5525900/7/src/libcamera/pipeline_handler.cpp#181 + return false; > } > > ++useCount_; > @@ -213,12 +215,35 @@ void PipelineHandler::release(Camera *camera) > --useCount_; > } > > +/** > + * \brief Acquire resources associated with this camera > + * \param[in] camera The camera for which to acquire resources > + * > + * Pipeline handlers may override this in order to get resources > + * such as open /dev nodes are allocate buffers when a camera is > + * acquired. > + * > + * Note this is called once for every camera which is acquired, > + * so if there are shared resources the pipeline handler must take > + * care to not release them until releaseDevice() has been called for > + * all previously acquired cameras. > + * > + * \return True on success, false on failure. > + * \sa releaseDevice() > + */ > +bool PipelineHandler::acquireDevice([[maybe_unused]] Camera *camera) > +{ > + return true; > +} > + > /** > * \brief Release resources associated with this camera > * \param[in] camera The camera for which to release resources > * > * Pipeline handlers may override this in order to perform cleanup > operations > * when a camera is released, such as freeing memory. > + * > + * \sa acquireDevice() > */ > void PipelineHandler::releaseDevice([[maybe_unused]] Camera *camera) > { > -- > 2.46.0 > > BR, Harvey
On Wed, Aug 21, 2024 at 06:55:45PM +0200, Cheng-Hao Yang wrote: > Hi Hans, > > Thanks for the patch. Actually in mtkisp7, we did something very similar > [1]. > (And I just caught a bug by checking your changes. Thanks :) > > [1]: > https://chromium-review.googlesource.com/c/chromiumos/third_party/libcamera/+/5525900 > > On Tue, Aug 20, 2024 at 9:50 PM Hans de Goede <hdegoede@redhat.com> wrote: > > > ATM libcamera always keeps all /dev/video# and /dev/v4l2_subdev# nodes > > for a pipeline open after enumerating the camera. > > > > This is a problem for uvcvideo and atomisp /dev/video# nodes as well as > > for VCM /dev/v4l2_subdev# nodes. Keeping these open stops the underlying > > hw-devices from being able to enter runtime-suspend causing significant > > unnecessary power-usage. > > > > Add a stub acquireDevice() method to the PipelineHandler class which > > pipeline handlers can override to delay opening /dev nodes until > > the camera is acquired. > > > > Note pipeline handlers typically also will need access to /dev nodes > > for their CameraConfig::validate() implementation for tryFormat() calls. > > Making sure that /dev nodes are opened as necessary from validate() is > > left up to the pipeline handler implementation. > > > > Signed-off-by: Hans de Goede <hdegoede@redhat.com> > > --- > > include/libcamera/internal/pipeline_handler.h | 3 +- > > src/libcamera/camera.cpp | 2 +- > > src/libcamera/pipeline_handler.cpp | 43 +++++++++++++++---- > > 3 files changed, 37 insertions(+), 11 deletions(-) > > > > diff --git a/include/libcamera/internal/pipeline_handler.h > > b/include/libcamera/internal/pipeline_handler.h > > index cad5812f..597f7c3e 100644 > > --- a/include/libcamera/internal/pipeline_handler.h > > +++ b/include/libcamera/internal/pipeline_handler.h > > @@ -45,7 +45,7 @@ public: > > MediaDevice *acquireMediaDevice(DeviceEnumerator *enumerator, > > const DeviceMatch &dm); > > > > - bool acquire(); > > + bool acquire(Camera *camera); > > void release(Camera *camera); > > > > virtual std::unique_ptr<CameraConfiguration> > > generateConfiguration(Camera *camera, > > @@ -79,6 +79,7 @@ protected: > > virtual int queueRequestDevice(Camera *camera, Request *request) = > > 0; > > virtual void stopDevice(Camera *camera) = 0; > > > > + virtual bool acquireDevice(Camera *camera); > > virtual void releaseDevice(Camera *camera); > > > > CameraManager *manager_; > > diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp > > index 382a68f7..4e393f89 100644 > > --- a/src/libcamera/camera.cpp > > +++ b/src/libcamera/camera.cpp > > @@ -995,7 +995,7 @@ int Camera::acquire() > > if (ret < 0) > > return ret == -EACCES ? -EBUSY : ret; > > > > - if (!d->pipe_->acquire()) { > > + if (!d->pipe_->acquire(this)) { > > LOG(Camera, Info) > > << "Pipeline handler in use by another process"; > > return -EBUSY; > > diff --git a/src/libcamera/pipeline_handler.cpp > > b/src/libcamera/pipeline_handler.cpp > > index 1fc22d6a..e1342306 100644 > > --- a/src/libcamera/pipeline_handler.cpp > > +++ b/src/libcamera/pipeline_handler.cpp > > @@ -163,20 +163,22 @@ MediaDevice > > *PipelineHandler::acquireMediaDevice(DeviceEnumerator *enumerator, > > * has already acquired it > > * \sa release() > > */ > > -bool PipelineHandler::acquire() > > +bool PipelineHandler::acquire(Camera *camera) > > { > > MutexLocker locker(lock_); > > > > - if (useCount_) { > > - ++useCount_; > > - return true; > > + if (useCount_ == 0) { > > + for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { > > + if (!media->lock()) { > > + unlockMediaDevices(); > > + return false; > > + } > > + } > > } > > > > - for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { > > - if (!media->lock()) { > > - unlockMediaDevices(); > > - return false; > > - } > > + if (!acquireDevice(camera)) { > > + unlockMediaDevices(); > > > > I think we should only unlock media devices if it's the first acquire > being called, as there might be other ongoing usages on other > cameras [2]. Therefore: > ``` > if (useCount_ == 0) > unlockMediaDevices(); > ``` > > [2]: > https://chromium-review.googlesource.com/c/chromiumos/third_party/libcamera/+/5525900/7/src/libcamera/pipeline_handler.cpp#181 > > + return false; > > } > > > > ++useCount_; > > @@ -213,12 +215,35 @@ void PipelineHandler::release(Camera *camera) > > --useCount_; > > } > > > > +/** > > + * \brief Acquire resources associated with this camera > > + * \param[in] camera The camera for which to acquire resources > > + * > > + * Pipeline handlers may override this in order to get resources > > + * such as open /dev nodes are allocate buffers when a camera is s@open /dev nodes@opening devices/ s/are allocate/and allocating/ As discussed previously, I think we need to improve the application-facing API to make resource and power management more explicit. Camera::acquire() was never meant for this purpose. I understand we need a short term solution to the power consumption issue for UVC cameras without an enormous amount of yak shaving, and I'm fine with this patch series as an interim measure, but I don't want to see acquireDevice() being used in random ways by pipeline handlers other than UVC before we address the more general problem. This should be documented here. > > + * acquired. Please reflow these paragraphs to 80 columns. > > + * > > + * Note this is called once for every camera which is acquired, s/which/that/ > > + * so if there are shared resources the pipeline handler must take s/shared resources/resources shared by multiple cameras/ > > + * care to not release them until releaseDevice() has been called for > > + * all previously acquired cameras. Doesn't this paragraph belong to releaseDevice() ? > > + * > > + * \return True on success, false on failure. > > + * \sa releaseDevice() > > + */ > > +bool PipelineHandler::acquireDevice([[maybe_unused]] Camera *camera) > > +{ > > + return true; > > +} > > + > > /** > > * \brief Release resources associated with this camera > > * \param[in] camera The camera for which to release resources > > * > > * Pipeline handlers may override this in order to perform cleanup > > operations > > * when a camera is released, such as freeing memory. > > + * > > + * \sa acquireDevice() > > */ > > void PipelineHandler::releaseDevice([[maybe_unused]] Camera *camera) > > {
Hi, On 8/21/24 6:55 PM, Cheng-Hao Yang wrote: > Hi Hans, > > Thanks for the patch. Actually in mtkisp7, we did something very similar [1]. > (And I just caught a bug by checking your changes. Thanks :) > > [1]: https://chromium-review.googlesource.com/c/chromiumos/third_party/libcamera/+/5525900 <https://chromium-review.googlesource.com/c/chromiumos/third_party/libcamera/+/5525900> > > On Tue, Aug 20, 2024 at 9:50 PM Hans de Goede <hdegoede@redhat.com <mailto:hdegoede@redhat.com>> wrote: > > ATM libcamera always keeps all /dev/video# and /dev/v4l2_subdev# nodes > for a pipeline open after enumerating the camera. > > This is a problem for uvcvideo and atomisp /dev/video# nodes as well as > for VCM /dev/v4l2_subdev# nodes. Keeping these open stops the underlying > hw-devices from being able to enter runtime-suspend causing significant > unnecessary power-usage. > > Add a stub acquireDevice() method to the PipelineHandler class which > pipeline handlers can override to delay opening /dev nodes until > the camera is acquired. > > Note pipeline handlers typically also will need access to /dev nodes > for their CameraConfig::validate() implementation for tryFormat() calls. > Making sure that /dev nodes are opened as necessary from validate() is > left up to the pipeline handler implementation. > > Signed-off-by: Hans de Goede <hdegoede@redhat.com <mailto:hdegoede@redhat.com>> > --- > include/libcamera/internal/pipeline_handler.h | 3 +- > src/libcamera/camera.cpp | 2 +- > src/libcamera/pipeline_handler.cpp | 43 +++++++++++++++---- > 3 files changed, 37 insertions(+), 11 deletions(-) > > diff --git a/include/libcamera/internal/pipeline_handler.h b/include/libcamera/internal/pipeline_handler.h > index cad5812f..597f7c3e 100644 > --- a/include/libcamera/internal/pipeline_handler.h > +++ b/include/libcamera/internal/pipeline_handler.h > @@ -45,7 +45,7 @@ public: > MediaDevice *acquireMediaDevice(DeviceEnumerator *enumerator, > const DeviceMatch &dm); > > - bool acquire(); > + bool acquire(Camera *camera); > void release(Camera *camera); > > virtual std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera, > @@ -79,6 +79,7 @@ protected: > virtual int queueRequestDevice(Camera *camera, Request *request) = 0; > virtual void stopDevice(Camera *camera) = 0; > > + virtual bool acquireDevice(Camera *camera); > virtual void releaseDevice(Camera *camera); > > CameraManager *manager_; > diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp > index 382a68f7..4e393f89 100644 > --- a/src/libcamera/camera.cpp > +++ b/src/libcamera/camera.cpp > @@ -995,7 +995,7 @@ int Camera::acquire() > if (ret < 0) > return ret == -EACCES ? -EBUSY : ret; > > - if (!d->pipe_->acquire()) { > + if (!d->pipe_->acquire(this)) { > LOG(Camera, Info) > << "Pipeline handler in use by another process"; > return -EBUSY; > diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp > index 1fc22d6a..e1342306 100644 > --- a/src/libcamera/pipeline_handler.cpp > +++ b/src/libcamera/pipeline_handler.cpp > @@ -163,20 +163,22 @@ MediaDevice *PipelineHandler::acquireMediaDevice(DeviceEnumerator *enumerator, > * has already acquired it > * \sa release() > */ > -bool PipelineHandler::acquire() > +bool PipelineHandler::acquire(Camera *camera) > { > MutexLocker locker(lock_); > > - if (useCount_) { > - ++useCount_; > - return true; > + if (useCount_ == 0) { > + for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { > + if (!media->lock()) { > + unlockMediaDevices(); > + return false; > + } > + } > } > > - for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { > - if (!media->lock()) { > - unlockMediaDevices(); > - return false; > - } > + if (!acquireDevice(camera)) { > + unlockMediaDevices(); > > > I think we should only unlock media devices if it's the first acquire > being called, as there might be other ongoing usages on other > cameras [2]. Therefore: > ``` > if (useCount_ == 0) > unlockMediaDevices(); > ``` Good point, fixed for v2. Regards, Hans
Hi, On 8/25/24 2:49 AM, Laurent Pinchart wrote: <snip> >>> @@ -213,12 +215,35 @@ void PipelineHandler::release(Camera *camera) >>> --useCount_; >>> } >>> >>> +/** >>> + * \brief Acquire resources associated with this camera >>> + * \param[in] camera The camera for which to acquire resources >>> + * >>> + * Pipeline handlers may override this in order to get resources >>> + * such as open /dev nodes are allocate buffers when a camera is > > s@open /dev nodes@opening devices/ > s/are allocate/and allocating/ Ack, fixed for v2. > As discussed previously, I think we need to improve the > application-facing API to make resource and power management more > explicit. Camera::acquire() was never meant for this purpose. I > understand we need a short term solution to the power consumption issue > for UVC cameras without an enormous amount of yak shaving Ack, I have posted a RFC with the application-facing API changes we discussed for this: https://lists.libcamera.org/pipermail/libcamera-devel/2024-August/044384.html > and I'm fine > with this patch series as an interim measure, but I don't want to see > acquireDevice() being used in random ways by pipeline handlers other > than UVC before we address the more general problem. This should be > documented here. Ok I have added the following block to the docbook comment to address this for v2: * This is used by the uvcvideo pipeline handler to delay opening /dev/video# * until the camera is acquired to avoid excess power consumption. The delayed * opening of /dev/video# is a special case because the kernel uvcvideo driver * powers on the USB device as soon as /dev/video# is opened. This behavior * must *not* be copied by other drivers. >>> + * acquired. > > Please reflow these paragraphs to 80 columns. Ack, done for v2. > >>> + * >>> + * Note this is called once for every camera which is acquired, > > s/which/that/ > >>> + * so if there are shared resources the pipeline handler must take > > s/shared resources/resources shared by multiple cameras/ > >>> + * care to not release them until releaseDevice() has been called for >>> + * all previously acquired cameras. > > Doesn't this paragraph belong to releaseDevice() ? that is a better place yes, I have moved it for v2. Regards, Hans
Hi Hans, On Tue, Aug 27, 2024 at 04:25:00PM +0200, Hans de Goede wrote: > On 8/25/24 2:49 AM, Laurent Pinchart wrote: > > <snip> > > >>> @@ -213,12 +215,35 @@ void PipelineHandler::release(Camera *camera) > >>> --useCount_; > >>> } > >>> > >>> +/** > >>> + * \brief Acquire resources associated with this camera > >>> + * \param[in] camera The camera for which to acquire resources > >>> + * > >>> + * Pipeline handlers may override this in order to get resources > >>> + * such as open /dev nodes are allocate buffers when a camera is > > > > s@open /dev nodes@opening devices/ > > s/are allocate/and allocating/ > > Ack, fixed for v2. > > > As discussed previously, I think we need to improve the > > application-facing API to make resource and power management more > > explicit. Camera::acquire() was never meant for this purpose. I > > understand we need a short term solution to the power consumption issue > > for UVC cameras without an enormous amount of yak shaving > > Ack, I have posted a RFC with the application-facing API changes we discussed > for this: > > https://lists.libcamera.org/pipermail/libcamera-devel/2024-August/044384.html Thank you for that. I really appreciate your efforts. I'll reply to the RFC after reviewing v2 of this series. > > and I'm fine > > with this patch series as an interim measure, but I don't want to see > > acquireDevice() being used in random ways by pipeline handlers other > > than UVC before we address the more general problem. This should be > > documented here. > > Ok I have added the following block to the docbook comment to address > this for v2: > > * This is used by the uvcvideo pipeline handler to delay opening /dev/video# > * until the camera is acquired to avoid excess power consumption. The delayed > * opening of /dev/video# is a special case because the kernel uvcvideo driver > * powers on the USB device as soon as /dev/video# is opened. This behavior > * must *not* be copied by other drivers. > > >>> + * acquired. > > > > Please reflow these paragraphs to 80 columns. > > Ack, done for v2. > > >>> + * > >>> + * Note this is called once for every camera which is acquired, > > > > s/which/that/ > > > >>> + * so if there are shared resources the pipeline handler must take > > > > s/shared resources/resources shared by multiple cameras/ > > > >>> + * care to not release them until releaseDevice() has been called for > >>> + * all previously acquired cameras. > > > > Doesn't this paragraph belong to releaseDevice() ? > > that is a better place yes, I have moved it for v2.
diff --git a/include/libcamera/internal/pipeline_handler.h b/include/libcamera/internal/pipeline_handler.h index cad5812f..597f7c3e 100644 --- a/include/libcamera/internal/pipeline_handler.h +++ b/include/libcamera/internal/pipeline_handler.h @@ -45,7 +45,7 @@ public: MediaDevice *acquireMediaDevice(DeviceEnumerator *enumerator, const DeviceMatch &dm); - bool acquire(); + bool acquire(Camera *camera); void release(Camera *camera); virtual std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera, @@ -79,6 +79,7 @@ protected: virtual int queueRequestDevice(Camera *camera, Request *request) = 0; virtual void stopDevice(Camera *camera) = 0; + virtual bool acquireDevice(Camera *camera); virtual void releaseDevice(Camera *camera); CameraManager *manager_; diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp index 382a68f7..4e393f89 100644 --- a/src/libcamera/camera.cpp +++ b/src/libcamera/camera.cpp @@ -995,7 +995,7 @@ int Camera::acquire() if (ret < 0) return ret == -EACCES ? -EBUSY : ret; - if (!d->pipe_->acquire()) { + if (!d->pipe_->acquire(this)) { LOG(Camera, Info) << "Pipeline handler in use by another process"; return -EBUSY; diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp index 1fc22d6a..e1342306 100644 --- a/src/libcamera/pipeline_handler.cpp +++ b/src/libcamera/pipeline_handler.cpp @@ -163,20 +163,22 @@ MediaDevice *PipelineHandler::acquireMediaDevice(DeviceEnumerator *enumerator, * has already acquired it * \sa release() */ -bool PipelineHandler::acquire() +bool PipelineHandler::acquire(Camera *camera) { MutexLocker locker(lock_); - if (useCount_) { - ++useCount_; - return true; + if (useCount_ == 0) { + for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { + if (!media->lock()) { + unlockMediaDevices(); + return false; + } + } } - for (std::shared_ptr<MediaDevice> &media : mediaDevices_) { - if (!media->lock()) { - unlockMediaDevices(); - return false; - } + if (!acquireDevice(camera)) { + unlockMediaDevices(); + return false; } ++useCount_; @@ -213,12 +215,35 @@ void PipelineHandler::release(Camera *camera) --useCount_; } +/** + * \brief Acquire resources associated with this camera + * \param[in] camera The camera for which to acquire resources + * + * Pipeline handlers may override this in order to get resources + * such as open /dev nodes are allocate buffers when a camera is + * acquired. + * + * Note this is called once for every camera which is acquired, + * so if there are shared resources the pipeline handler must take + * care to not release them until releaseDevice() has been called for + * all previously acquired cameras. + * + * \return True on success, false on failure. + * \sa releaseDevice() + */ +bool PipelineHandler::acquireDevice([[maybe_unused]] Camera *camera) +{ + return true; +} + /** * \brief Release resources associated with this camera * \param[in] camera The camera for which to release resources * * Pipeline handlers may override this in order to perform cleanup operations * when a camera is released, such as freeing memory. + * + * \sa acquireDevice() */ void PipelineHandler::releaseDevice([[maybe_unused]] Camera *camera) {
ATM libcamera always keeps all /dev/video# and /dev/v4l2_subdev# nodes for a pipeline open after enumerating the camera. This is a problem for uvcvideo and atomisp /dev/video# nodes as well as for VCM /dev/v4l2_subdev# nodes. Keeping these open stops the underlying hw-devices from being able to enter runtime-suspend causing significant unnecessary power-usage. Add a stub acquireDevice() method to the PipelineHandler class which pipeline handlers can override to delay opening /dev nodes until the camera is acquired. Note pipeline handlers typically also will need access to /dev nodes for their CameraConfig::validate() implementation for tryFormat() calls. Making sure that /dev nodes are opened as necessary from validate() is left up to the pipeline handler implementation. Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- include/libcamera/internal/pipeline_handler.h | 3 +- src/libcamera/camera.cpp | 2 +- src/libcamera/pipeline_handler.cpp | 43 +++++++++++++++---- 3 files changed, 37 insertions(+), 11 deletions(-)