libcamera: pipeline: uvcvideo: Fix `ExposureTimeMode` control setting

The mapping in `UVCCameraData::processControl()` is not entirely correct
because the control value is retrieved as a `bool` instead of `int32_t`.
Additionally, the available modes are not taken into account.

Retrieve the control value with the right type, `int32_t`, check if the
requested mode is available, and if so, set the appropriate V4L2 control
value selected by `addControl()` earlier.

Fixes: bad8d591f8acfa ("libcamera: uvcvideo: Register ExposureTimeMode control")
Signed-off-by: Barnabás Pőcze <barnabas.pocze@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>

1 files changed, 20 insertions, 9 deletions

diff --git a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
index 3a2a64cf..5adc89fd 100644
--- a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
@@ -98,8 +98,8 @@ public:
 	bool match(DeviceEnumerator *enumerator) override;
 
 private:
-	int processControl(ControlList *controls, unsigned int id,
-			   const ControlValue &value);
+	int processControl(const UVCCameraData *data, ControlList *controls,
+			   unsigned int id, const ControlValue &value);
 	int processControls(UVCCameraData *data, Request *request);
 
 	bool acquireDevice(Camera *camera) override;
@@ -312,8 +312,8 @@ void PipelineHandlerUVC::stopDevice(Camera *camera)
 	data->video_->releaseBuffers();
 }
 
-int PipelineHandlerUVC::processControl(ControlList *controls, unsigned int id,
-				       const ControlValue &value)
+int PipelineHandlerUVC::processControl(const UVCCameraData *data, ControlList *controls,
+				       unsigned int id, const ControlValue &value)
 {
 	uint32_t cid;
 
@@ -357,10 +357,21 @@ int PipelineHandlerUVC::processControl(ControlList *controls, unsigned int id,
 	}
 
 	case V4L2_CID_EXPOSURE_AUTO: {
-		int32_t ivalue = value.get<bool>()
-			       ? V4L2_EXPOSURE_APERTURE_PRIORITY
-			       : V4L2_EXPOSURE_MANUAL;
-		controls->set(V4L2_CID_EXPOSURE_AUTO, ivalue);
+		std::optional<v4l2_exposure_auto_type> mode;
+
+		switch (value.get<int32_t>()) {
+		case controls::ExposureTimeModeAuto:
+			mode = data->autoExposureMode_;
+			break;
+		case controls::ExposureTimeModeManual:
+			mode = data->manualExposureMode_;
+			break;
+		}
+
+		if (!mode)
+			return -EINVAL;
+
+		controls->set(V4L2_CID_EXPOSURE_AUTO, static_cast<int32_t>(*mode));
 		break;
 	}
 
@@ -398,7 +409,7 @@ int PipelineHandlerUVC::processControls(UVCCameraData *data, Request *request)
 	ControlList controls(data->video_->controls());
 
 	for (const auto &[id, value] : request->controls())
-		processControl(&controls, id, value);
+		processControl(data, &controls, id, value);
 
 	for (const auto &ctrl : controls)
 		LOG(UVC, Debug)