[libcamera-devel] [PATCH v2 4/7] libcamera: pipelines: add method to configure streams

[Niklas Söderlund]

All the streams which are to be used needs to be configured at the same
time, that is passed from the application to the pipeline handler in a
single call. This would allow the pipeline handler to take any
dependences between the different streams and there configuration into
account when setting up the hardware.

This implementation do not interact with any hardware, instead it
extends all pipeline handlers with the argument validation needed to
make sure the configuration request is sound. It then proceeds to print
the requested frame dimensions to the log. Future work based on more
components are needed to make the pipeline specific implementations
truly useful.

Signed-off-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
---
 src/libcamera/include/pipeline_handler.h |  3 +++
 src/libcamera/pipeline/ipu3/ipu3.cpp     | 21 +++++++++++++++++++++
 src/libcamera/pipeline/uvcvideo.cpp      | 24 ++++++++++++++++++++++++
 src/libcamera/pipeline/vimc.cpp          | 24 ++++++++++++++++++++++++
 src/libcamera/pipeline_handler.cpp       | 18 ++++++++++++++++++
 5 files changed, 90 insertions(+)

diff --git a/src/libcamera/include/pipeline_handler.h b/src/libcamera/include/pipeline_handler.h
index f92cc5b5fa5e777b..5813e00aec068356 100644
--- a/src/libcamera/include/pipeline_handler.h
+++ b/src/libcamera/include/pipeline_handler.h
@@ -18,6 +18,7 @@ class CameraManager;
 class DeviceEnumerator;
 class MediaDevice;
 class Stream;
+class StreamConfiguration;
 
 class Camera;
 class CameraData
@@ -41,6 +42,8 @@ public:
 
 	virtual std::vector<Stream> streams(const Camera *camera) const = 0;
 
+	virtual int configure(const Camera *camera, std::vector<StreamConfiguration *> &config) = 0;
+
 	virtual bool match(DeviceEnumerator *enumerator) = 0;
 
 protected:
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 5c35c7a53b9347a3..2d790f72dc63c31b 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -30,6 +30,8 @@ public:
 
 	std::vector<Stream> streams(const Camera *camera) const;
 
+	int configure(const Camera *camera, std::vector<StreamConfiguration *> &config);
+
 	bool match(DeviceEnumerator *enumerator);
 
 private:
@@ -72,6 +74,25 @@ std::vector<Stream> PipelineHandlerIPU3::streams(const Camera *camera) const
 	return streams;
 }
 
+int PipelineHandlerIPU3::configure(const Camera *camera,
+				   std::vector<StreamConfiguration *> &config)
+{
+	StreamConfiguration *cfg;
+
+	if (config.size() != 1)
+		return -EINVAL;
+
+	cfg = config.front();
+
+	if (!cfg || cfg->id() != 0)
+		return -EINVAL;
+
+	LOG(IPU3, Info) << "TODO: Configure the camera for resolution " <<
+		cfg->width() << "x" << cfg->height();
+
+	return 0;
+}
+
 bool PipelineHandlerIPU3::match(DeviceEnumerator *enumerator)
 {
 	DeviceMatch cio2_dm("ipu3-cio2");
diff --git a/src/libcamera/pipeline/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo.cpp
index e1f023245b8e63dd..477a9fe7f56d9a75 100644
--- a/src/libcamera/pipeline/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo.cpp
@@ -9,12 +9,15 @@
 #include <libcamera/stream.h>
 
 #include "device_enumerator.h"
+#include "log.h"
 #include "media_device.h"
 #include "pipeline_handler.h"
 #include "v4l2_device.h"
 
 namespace libcamera {
 
+LOG_DEFINE_CATEGORY(UVC)
+
 class PipelineHandlerUVC : public PipelineHandler
 {
 public:
@@ -23,6 +26,8 @@ public:
 
 	std::vector<Stream> streams(const Camera *camera) const;
 
+	int configure(const Camera *camera, std::vector<StreamConfiguration *> &config);
+
 	bool match(DeviceEnumerator *enumerator);
 
 private:
@@ -53,6 +58,25 @@ std::vector<Stream> PipelineHandlerUVC::streams(const Camera *camera) const
 	return streams;
 }
 
+int PipelineHandlerUVC::configure(const Camera *camera,
+				  std::vector<StreamConfiguration *> &config)
+{
+	StreamConfiguration *cfg;
+
+	if (config.size() != 1)
+		return -EINVAL;
+
+	cfg = config.front();
+
+	if (!cfg || cfg->id() != 0)
+		return -EINVAL;
+
+	LOG(UVC, Info) << "TODO: Configure the camera for resolution " <<
+		cfg->width() << "x" << cfg->height();
+
+	return 0;
+}
+
 bool PipelineHandlerUVC::match(DeviceEnumerator *enumerator)
 {
 	DeviceMatch dm("uvcvideo");
diff --git a/src/libcamera/pipeline/vimc.cpp b/src/libcamera/pipeline/vimc.cpp
index a96ec9f431361a32..f9d3b3a604805baa 100644
--- a/src/libcamera/pipeline/vimc.cpp
+++ b/src/libcamera/pipeline/vimc.cpp
@@ -9,11 +9,14 @@
 #include <libcamera/stream.h>
 
 #include "device_enumerator.h"
+#include "log.h"
 #include "media_device.h"
 #include "pipeline_handler.h"
 
 namespace libcamera {
 
+LOG_DEFINE_CATEGORY(VIMC)
+
 class PipeHandlerVimc : public PipelineHandler
 {
 public:
@@ -22,6 +25,8 @@ public:
 
 	std::vector<Stream> streams(const Camera *camera) const;
 
+	int configure(const Camera *camera, std::vector<StreamConfiguration *> &config);
+
 	bool match(DeviceEnumerator *enumerator);
 
 private:
@@ -48,6 +53,25 @@ std::vector<Stream> PipeHandlerVimc::streams(const Camera *camera) const
 	return streams;
 }
 
+int PipeHandlerVimc::configure(const Camera *camera,
+			       std::vector<StreamConfiguration *> &config)
+{
+	StreamConfiguration *cfg;
+
+	if (config.size() != 1)
+		return -EINVAL;
+
+	cfg = config.front();
+
+	if (!cfg || cfg->id() != 0)
+		return -EINVAL;
+
+	LOG(VIMC, Info) << "TODO: Configure the camera for resolution " <<
+		cfg->width() << "x" << cfg->height();
+
+	return 0;
+}
+
 bool PipeHandlerVimc::match(DeviceEnumerator *enumerator)
 {
 	DeviceMatch dm("vimc");
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index a825e7bf882d23c2..dc3535f105e3a992 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -96,6 +96,24 @@ PipelineHandler::~PipelineHandler()
  *         is not part of the PipelineHandler.
  */
 
+/**
+ * \fn PipelineHandler::configure(const Camera *camera, std::vector<StreamConfiguration *> &config)
+ * \brief Configure a set of streams for a camera
+ * \param[in] camera The camera to configure streams for
+ * \param[in] config A array of stream configurations to try and setup
+ *
+ * This function is the interface to configure one or more streams of a camera
+ * for capture. The intended user for this interface is the Camera class which
+ * will receive the array of configurations to apply from the application.
+ *
+ * The caller needs to verify the StreamConfiguration objects in the passed
+ * array after the call as it might remove one or more to satisfy hardware
+ * limitations. The call might also alter any or all of the configuration
+ * parameters of any stream to fit within valid operational conditions.
+ *
+ * \return 0 on success or a negative error code on error.
+ */
+
 /**
  * \fn PipelineHandler::match(DeviceEnumerator *enumerator)
  * \brief Match media devices and create camera instances
-- 
2.20.1