[PATCH] libcamera: camera: Log info message to report camera creation

[Laurent Pinchart]

On Mon, Mar 03, 2025 at 02:18:20PM +0100, Barnabás Pőcze wrote:
> 2025. 03. 03. 14:10 keltezéssel, Barnabás Pőcze írta:
> > 2025. 02. 26. 1:55 keltezéssel, Laurent Pinchart írta:
> >> Camera creation is one of the most important events generated by
> >> libcamera, but we are completely silent about it. The lack of a log
> >> message makes it more difficult to identify problems and provide
> >> support. Fix it by adding an Info message that reports the camera id and
> >> its pipeline handler when the camera is created.
> >>
> >> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> >> ---
> >>   src/libcamera/camera.cpp | 4 ++++
> >>   1 file changed, 4 insertions(+)
> >>
> >> diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
> >> index 56c5851993c9..35097bfdafa2 100644
> >> --- a/src/libcamera/camera.cpp
> >> +++ b/src/libcamera/camera.cpp
> >> @@ -862,6 +862,10 @@ std::shared_ptr<Camera> Camera::create(std::unique_ptr<Private> d,
> >>           }
> >>       };
> >>
> >> +    LOG(Camera, Info)
> >> +        << "Creating camera '" << id << "' for pipeline handler "
> >> +        << d->pipe_->name();
> >> +
> > 
> > I have a similar change locally but it adds log messages to `CameraManager::{add,remove}Camera()`,
> > not sure which is the better place, but I think the removal also deserves at
> > least a "Debug" message. I am also wondering if the "Info" level is not too high?
> 
> Sorry, there is already a message in `removeCamera()`... I don't know
> what I was hallucinating...

The message could go to CameraManager::Private::addCamera() indeed, to
match CameraManager::Private::removeCamera(). I've picked Info on
purpose, I think this is an important event that deserves it.

I'll send a v2 that moves the message to the CameraManager class.

> >>       Camera *camera = new Camera(std::move(d), id, streams);
> >>
> >>       return std::shared_ptr<Camera>(camera, Deleter());
> >>
> >> base-commit: 33ce463a46c44f874fdbc3e484bee730e7b251a3

-- 
Regards,

Laurent Pinchart