libcamera: stream: Add stream configuration to the stream object

Add a cache of the active stream configuration to the stream object.
This cache is to be updated from the Camera object and can be accessed
read only from both the application and pipeline handlers.

Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

2 files changed, 48 insertions, 34 deletions

diff --git a/include/libcamera/stream.h b/include/libcamera/stream.h
index 111f2c93..3e8e83a2 100644
--- a/include/libcamera/stream.h
+++ b/include/libcamera/stream.h
@@ -11,23 +11,31 @@
 
 namespace libcamera {
 
+class Camera;
+
+struct StreamConfiguration {
+	unsigned int width;
+	unsigned int height;
+	unsigned int pixelFormat;
+
+	unsigned int bufferCount;
+};
+
 class Stream final
 {
 public:
 	Stream();
 	BufferPool &bufferPool() { return bufferPool_; }
+	const StreamConfiguration &configuration() const { return configuration_; }
 
 private:
+	friend Camera;
+
 	BufferPool bufferPool_;
+	StreamConfiguration configuration_;
 };
 
-struct StreamConfiguration {
-	unsigned int width;
-	unsigned int height;
-	unsigned int pixelFormat;
 
-	unsigned int bufferCount;
-};
 
 } /* namespace libcamera */
 
diff --git a/src/libcamera/stream.cpp b/src/libcamera/stream.cpp
index b6238946..c4943c91 100644
--- a/src/libcamera/stream.cpp
+++ b/src/libcamera/stream.cpp
@@ -30,6 +30,37 @@
 namespace libcamera {
 
 /**
+ * \struct StreamConfiguration
+ * \brief Configuration parameters for a stream
+ *
+ * The StreamConfiguration structure models all information which can be
+ * configured for a single video stream.
+ */
+
+/**
+ * \var StreamConfiguration::width
+ * \brief Stream width in pixels
+ */
+
+/**
+ * \var StreamConfiguration::height
+ * \brief Stream height in pixels
+ */
+
+/**
+ * \var StreamConfiguration::pixelFormat
+ * \brief Stream pixel format
+ *
+ * This is a little endian four character code representation of the pixel
+ * format described in V4L2 using the V4L2_PIX_FMT_* definitions.
+ */
+
+/**
+ * \var StreamConfiguration::bufferCount
+ * \brief Requested number of buffers to allocate for the stream
+ */
+
+/**
  * \class Stream
  * \brief Video stream for a camera
  *
@@ -66,34 +97,9 @@ Stream::Stream()
  */
 
 /**
- * \struct StreamConfiguration
- * \brief Configuration parameters for a stream
- *
- * The StreamConfiguration structure models all information which can be
- * configured for a single video stream.
- */
-
-/**
- * \var StreamConfiguration::width
- * \brief Stream width in pixels
- */
-
-/**
- * \var StreamConfiguration::height
- * \brief Stream height in pixels
- */
-
-/**
- * \var StreamConfiguration::pixelFormat
- * \brief Stream pixel format
- *
- * This is a little endian four character code representation of the pixel
- * format described in V4L2 using the V4L2_PIX_FMT_* definitions.
- */
-
-/**
- * \var StreamConfiguration::bufferCount
- * \brief Requested number of buffers to allocate for the stream
+ * \fn Stream::configuration()
+ * \brief Retrieve the active configuration of the stream
+ * \return The active configuration of the stream
  */
 
 } /* namespace libcamera */