[libcamera-devel] [PATCH] libcamera: camera_sensor: Print missing controls names

[Kieran Bingham]

Quoting Jacopo Mondi via libcamera-devel (2022-11-22 08:30:05)
> Since the very beginning the camera sensor class has validated the
> controls available from the camera sensor driver, and complained
> accordingly when any of them was missing.
> 
> The complaint message reported however only the numerical identifier of
> the V4L2 control, making debugging harder.
> 
> Associate to each control a human readable identifier and use it in
> debug messages.
> 

Screams in 'YES PLEASE' [0] [1]

[0] https://patchwork.libcamera.org/patch/13346/ (13/08/2021)
[1] https://patchwork.libcamera.org/patch/11178/ (05/02/2021)

Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>  src/libcamera/camera_sensor.cpp | 38 ++++++++++++++++-----------------
>  1 file changed, 19 insertions(+), 19 deletions(-)
> 
> diff --git a/src/libcamera/camera_sensor.cpp b/src/libcamera/camera_sensor.cpp
> index ea373458a164..0780ce5a7007 100644
> --- a/src/libcamera/camera_sensor.cpp
> +++ b/src/libcamera/camera_sensor.cpp
> @@ -213,31 +213,31 @@ int CameraSensor::validateSensorDriver()
>          * Optional controls are used to register optional sensor properties. If
>          * not present, some values will be defaulted.
>          */
> -       static constexpr uint32_t optionalControls[] = {
> -               V4L2_CID_CAMERA_SENSOR_ROTATION,
> +       static const std::map<uint32_t, std::string> optionalControls = {
> +               { V4L2_CID_CAMERA_SENSOR_ROTATION, "Rotation" },
>         };
>  
>         const ControlIdMap &controls = subdev_->controls().idmap();
> -       for (uint32_t ctrl : optionalControls) {
> +       for (const auto &[ctrl, name] : optionalControls) {
>                 if (!controls.count(ctrl))
>                         LOG(CameraSensor, Debug)
> -                               << "Optional V4L2 control " << utils::hex(ctrl)
> -                               << " not supported";
> +                               << "Optional V4L2 control '" << name
> +                               << "' not supported";
>         }
>  
>         /*
>          * Recommended controls are similar to optional controls, but will
>          * become mandatory in the near future. Be loud if they're missing.
>          */
> -       static constexpr uint32_t recommendedControls[] = {
> -               V4L2_CID_CAMERA_ORIENTATION,
> +       static const std::map<uint32_t, std::string> recommendedControls = {
> +               { V4L2_CID_CAMERA_ORIENTATION, "Orientation" },
>         };
>  
> -       for (uint32_t ctrl : recommendedControls) {
> +       for (const auto &[ctrl, name] : recommendedControls) {
>                 if (!controls.count(ctrl)) {
>                         LOG(CameraSensor, Warning)
> -                               << "Recommended V4L2 control " << utils::hex(ctrl)
> -                               << " not supported";
> +                               << "Recommended V4L2 control '" << name
> +                               << "' not supported";
>                         err = -EINVAL;
>                 }
>         }
> @@ -300,20 +300,20 @@ int CameraSensor::validateSensorDriver()
>          * For raw sensors, make sure the sensor driver supports the controls
>          * required by the CameraSensor class.
>          */
> -       static constexpr uint32_t mandatoryControls[] = {
> -               V4L2_CID_ANALOGUE_GAIN,
> -               V4L2_CID_EXPOSURE,
> -               V4L2_CID_HBLANK,
> -               V4L2_CID_PIXEL_RATE,
> -               V4L2_CID_VBLANK,
> +       static const std::map<uint32_t, std::string> mandatoryControls = {
> +               { V4L2_CID_ANALOGUE_GAIN, "Analogue gain" },
> +               { V4L2_CID_EXPOSURE, "Exposure" },
> +               { V4L2_CID_HBLANK, "Horizontal blanking" },
> +               { V4L2_CID_PIXEL_RATE, "Pixel Rate" },
> +               { V4L2_CID_VBLANK, "Vertical blanking" }
>         };
>  
>         err = 0;
> -       for (uint32_t ctrl : mandatoryControls) {
> +       for (const auto &[ctrl, name] : mandatoryControls) {
>                 if (!controls.count(ctrl)) {
>                         LOG(CameraSensor, Error)
> -                               << "Mandatory V4L2 control " << utils::hex(ctrl)
> -                               << " not available";
> +                               << "Mandatory V4L2 control '" << name
> +                               << "' not available";
>                         err = -EINVAL;
>                 }
>         }
> -- 
> 2.38.1
>