[libcamera-devel,1/5] libcamera: delayed_controls: Add notion of priority write
diff mbox series

Message ID 20210212113312.239076-2-naush@raspberrypi.com
State Superseded
Headers show
Series
  • DelayedControls updates and fixes
Related show

Commit Message

Naushir Patuck Feb. 12, 2021, 11:33 a.m. UTC
If an exposure time change adjusts the vblanking limits, and we write
both VBLANK and EXPOSURE controls as a set, the latter may fail if the
value is outside of the limits calculated by the old VBLANK value. This
is a limitation in V4L2 and cannot be fixed by writing VBLANK before
EXPOSURE.

The workaround here is to have the DelayedControls object mark the
VBLANK control as "priority write", which then write VBLANK separately
from (and ahead of) any other controls. This way, the sensor driver will
update the EXPOSURE control with new limits before the new values is
presented, and will thus be seen as valid.

To support this, a new struct DelayedControls::ControlParams is used in
the constructor to provide the control delay value as well as the
priority write flag.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
---
 include/libcamera/internal/delayed_controls.h |  9 +++-
 src/libcamera/delayed_controls.cpp            | 54 +++++++++++++------
 src/libcamera/pipeline/ipu3/ipu3.cpp          |  8 +--
 .../pipeline/raspberrypi/raspberrypi.cpp      | 13 +++--
 src/libcamera/pipeline/rkisp1/rkisp1.cpp      |  8 +--
 test/delayed_contols.cpp                      | 20 +++----
 6 files changed, 68 insertions(+), 44 deletions(-)

Patch
diff mbox series

diff --git a/include/libcamera/internal/delayed_controls.h b/include/libcamera/internal/delayed_controls.h
index dc447a882514..564d9f2e2440 100644
--- a/include/libcamera/internal/delayed_controls.h
+++ b/include/libcamera/internal/delayed_controls.h
@@ -19,8 +19,13 @@  class V4L2Device;
 class DelayedControls
 {
 public:
+	struct ControlParams {
+		unsigned int delay;
+		bool priorityWrite;
+	};
+
 	DelayedControls(V4L2Device *device,
-			const std::unordered_map<uint32_t, unsigned int> &delays);
+			const std::unordered_map<uint32_t, ControlParams> &controlParams);
 
 	void reset();
 
@@ -64,7 +69,7 @@  private:
 
 	V4L2Device *device_;
 	/* \todo Evaluate if we should index on ControlId * or unsigned int */
-	std::unordered_map<const ControlId *, unsigned int> delays_;
+	std::unordered_map<const ControlId *, ControlParams> controlParams_;
 	unsigned int maxDelay_;
 
 	bool running_;
diff --git a/src/libcamera/delayed_controls.cpp b/src/libcamera/delayed_controls.cpp
index ab1d40057c5f..5317f820b6bd 100644
--- a/src/libcamera/delayed_controls.cpp
+++ b/src/libcamera/delayed_controls.cpp
@@ -40,15 +40,19 @@  LOG_DEFINE_CATEGORY(DelayedControls)
 /**
  * \brief Construct a DelayedControls instance
  * \param[in] device The V4L2 device the controls have to be applied to
- * \param[in] delays Map of the numerical V4L2 control ids to their associated
- * delays (in frames)
+ * \param[in] controlParams Map of the numerical V4L2 control ids to their
+ * associated control parameters.
  *
- * Only controls specified in \a delays are handled. If it's desired to mix
- * delayed controls and controls that take effect immediately the immediate
- * controls must be listed in the \a delays map with a delay value of 0.
+ * The control parameters comprise of delays (in frames) and a priority write
+ * flag. If this flag is set, the relevant control is written separately from,
+ * ahead of the reset of the batched controls.
+ *
+ * Only controls specified in \a controlParams are handled. If it's desired to
+ * mix delayed controls and controls that take effect immediately the immediate
+ * controls must be listed in the \a controlParams map with a delay value of 0.
  */
 DelayedControls::DelayedControls(V4L2Device *device,
-				 const std::unordered_map<uint32_t, unsigned int> &delays)
+				 const std::unordered_map<uint32_t, ControlParams> &controlParams)
 	: device_(device), maxDelay_(0)
 {
 	const ControlInfoMap &controls = device_->controls();
@@ -57,12 +61,12 @@  DelayedControls::DelayedControls(V4L2Device *device,
 	 * Create a map of control ids to delays for controls exposed by the
 	 * device.
 	 */
-	for (auto const &delay : delays) {
-		auto it = controls.find(delay.first);
+	for (auto const &param : controlParams) {
+		auto it = controls.find(param.first);
 		if (it == controls.end()) {
 			LOG(DelayedControls, Error)
 				<< "Delay request for control id "
-				<< utils::hex(delay.first)
+				<< utils::hex(param.first)
 				<< " but control is not exposed by device "
 				<< device_->deviceNode();
 			continue;
@@ -70,13 +74,14 @@  DelayedControls::DelayedControls(V4L2Device *device,
 
 		const ControlId *id = it->first;
 
-		delays_[id] = delay.second;
+		controlParams_[id] = param.second;
 
 		LOG(DelayedControls, Debug)
-			<< "Set a delay of " << delays_[id]
+			<< "Set a delay of " << controlParams_[id].delay
+			<< " and priority write flag " << controlParams_[id].priorityWrite
 			<< " for " << id->name();
 
-		maxDelay_ = std::max(maxDelay_, delays_[id]);
+		maxDelay_ = std::max(maxDelay_, controlParams_[id].delay);
 	}
 
 	reset();
@@ -97,8 +102,8 @@  void DelayedControls::reset()
 
 	/* Retrieve control as reported by the device. */
 	std::vector<uint32_t> ids;
-	for (auto const &delay : delays_)
-		ids.push_back(delay.first->id());
+	for (auto const &param : controlParams_)
+		ids.push_back(param.first->id());
 
 	ControlList controls = device_->getControls(ids);
 
@@ -140,7 +145,7 @@  bool DelayedControls::push(const ControlList &controls)
 
 		const ControlId *id = it->second;
 
-		if (delays_.find(id) == delays_.end())
+		if (controlParams_.find(id) == controlParams_.end())
 			return false;
 
 		Info &info = values_[id][queueCount_];
@@ -220,12 +225,27 @@  void DelayedControls::applyControls(uint32_t sequence)
 	ControlList out(device_->controls());
 	for (const auto &ctrl : values_) {
 		const ControlId *id = ctrl.first;
-		unsigned int delayDiff = maxDelay_ - delays_[id];
+		unsigned int delayDiff = maxDelay_ - controlParams_[id].delay;
 		unsigned int index = std::max<int>(0, writeCount_ - delayDiff);
 		const Info &info = ctrl.second[index];
 
 		if (info.updated) {
-			out.set(id->id(), info);
+			if (controlParams_[id].priorityWrite) {
+				/*
+				 * This control must be written now, it could
+				 * affect validity of the other controls.
+				 */
+				ControlList priority(device_->controls());
+				priority.set(id->id(), info);
+				device_->setControls(&priority);
+			} else {
+				/*
+				 * Batch up the list of controls and write them
+				 * at the end of the function.
+				 */
+				out.set(id->id(), info);
+			}
+
 			LOG(DelayedControls, Debug)
 				<< "Setting " << id->name()
 				<< " to " << info.toString()
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 61f7bf43ea08..eda07d915f0c 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -988,14 +988,14 @@  int PipelineHandlerIPU3::registerCameras()
 		 * a sensor database. For now use generic values taken from
 		 * the Raspberry Pi and listed as 'generic values'.
 		 */
-		std::unordered_map<uint32_t, unsigned int> delays = {
-			{ V4L2_CID_ANALOGUE_GAIN, 1 },
-			{ V4L2_CID_EXPOSURE, 2 },
+		std::unordered_map<uint32_t, DelayedControls::ControlParams> params = {
+			{ V4L2_CID_ANALOGUE_GAIN, { 1, false } },
+			{ V4L2_CID_EXPOSURE, { 2, false } },
 		};
 
 		data->delayedCtrls_ =
 			std::make_unique<DelayedControls>(cio2->sensor()->device(),
-							  delays);
+							  params);
 		data->cio2_.frameStart().connect(data->delayedCtrls_.get(),
 						 &DelayedControls::applyControls);
 
diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
index b0bb12ab0f37..bdb439021c46 100644
--- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
+++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
@@ -1273,16 +1273,15 @@  int RPiCameraData::configureIPA(const CameraConfiguration *config)
 	if (result.operation & RPi::IPA_RESULT_SENSOR_PARAMS) {
 		/*
 		 * Setup our delayed control writer with the sensor default
-		 * gain and exposure delays.
+		 * gain and exposure delays. Mark VBLANK for priority write.
 		 */
-		std::unordered_map<uint32_t, unsigned int> delays = {
-			{ V4L2_CID_ANALOGUE_GAIN, result.data[resultIdx++] },
-			{ V4L2_CID_EXPOSURE, result.data[resultIdx++] },
-			{ V4L2_CID_VBLANK, result.data[resultIdx++] }
+		std::unordered_map<uint32_t, DelayedControls::ControlParams> params = {
+			{ V4L2_CID_ANALOGUE_GAIN, { result.data[resultIdx++], false } },
+			{ V4L2_CID_EXPOSURE, { result.data[resultIdx++], false } },
+			{ V4L2_CID_VBLANK, { result.data[resultIdx++], true } }
 		};
 
-		delayedCtrls_ = std::make_unique<DelayedControls>(unicam_[Unicam::Image].dev(), delays);
-
+		delayedCtrls_ = std::make_unique<DelayedControls>(unicam_[Unicam::Image].dev(), params);
 		sensorMetadata_ = result.data[resultIdx++];
 	}
 
diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
index e85979a719b7..ea9b1e2b9fcb 100644
--- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
+++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
@@ -942,14 +942,14 @@  int PipelineHandlerRkISP1::createCamera(MediaEntity *sensor)
 	 * a sensor database. For now use generic values taken from
 	 * the Raspberry Pi and listed as generic values.
 	 */
-	std::unordered_map<uint32_t, unsigned int> delays = {
-		{ V4L2_CID_ANALOGUE_GAIN, 1 },
-		{ V4L2_CID_EXPOSURE, 2 },
+	std::unordered_map<uint32_t, DelayedControls::ControlParams> params = {
+		{ V4L2_CID_ANALOGUE_GAIN, { 1, false } },
+		{ V4L2_CID_EXPOSURE, { 2, false } },
 	};
 
 	data->delayedCtrls_ =
 		std::make_unique<DelayedControls>(data->sensor_->device(),
-						  delays);
+						  params);
 	isp_->frameStart.connect(data->delayedCtrls_.get(),
 				 &DelayedControls::applyControls);
 
diff --git a/test/delayed_contols.cpp b/test/delayed_contols.cpp
index 50169b12e566..3855eb18ecd4 100644
--- a/test/delayed_contols.cpp
+++ b/test/delayed_contols.cpp
@@ -72,8 +72,8 @@  protected:
 
 	int singleControlNoDelay()
 	{
-		std::unordered_map<uint32_t, unsigned int> delays = {
-			{ V4L2_CID_BRIGHTNESS, 0 },
+		std::unordered_map<uint32_t, DelayedControls::ControlParams> delays = {
+			{ V4L2_CID_BRIGHTNESS, { 0, false } },
 		};
 		std::unique_ptr<DelayedControls> delayed =
 			std::make_unique<DelayedControls>(dev_.get(), delays);
@@ -109,8 +109,8 @@  protected:
 
 	int singleControlWithDelay()
 	{
-		std::unordered_map<uint32_t, unsigned int> delays = {
-			{ V4L2_CID_BRIGHTNESS, 1 },
+		std::unordered_map<uint32_t, DelayedControls::ControlParams> delays = {
+			{ V4L2_CID_BRIGHTNESS, { 1, false } },
 		};
 		std::unique_ptr<DelayedControls> delayed =
 			std::make_unique<DelayedControls>(dev_.get(), delays);
@@ -150,9 +150,9 @@  protected:
 
 	int dualControlsWithDelay(uint32_t startOffset)
 	{
-		std::unordered_map<uint32_t, unsigned int> delays = {
-			{ V4L2_CID_BRIGHTNESS, 1 },
-			{ V4L2_CID_CONTRAST, 2 },
+		std::unordered_map<uint32_t, DelayedControls::ControlParams> delays = {
+			{ V4L2_CID_BRIGHTNESS, { 1, false } },
+			{ V4L2_CID_CONTRAST, { 2, false } },
 		};
 		std::unique_ptr<DelayedControls> delayed =
 			std::make_unique<DelayedControls>(dev_.get(), delays);
@@ -197,9 +197,9 @@  protected:
 
 	int dualControlsMultiQueue()
 	{
-		std::unordered_map<uint32_t, unsigned int> delays = {
-			{ V4L2_CID_BRIGHTNESS, 1 },
-			{ V4L2_CID_CONTRAST, 2 },
+		std::unordered_map<uint32_t, DelayedControls::ControlParams> delays = {
+			{ V4L2_CID_BRIGHTNESS, { 1, false } },
+			{ V4L2_CID_CONTRAST, { 2, false } }
 		};
 		std::unique_ptr<DelayedControls> delayed =
 			std::make_unique<DelayedControls>(dev_.get(), delays);