@@ -1040,8 +1040,9 @@ void IPARPi::applyAGC(const struct AgcStatus *agcStatus, ControlList &ctrls)
/*
* Due to the behavior of V4L2, the current value of VBLANK could clip the
- * exposure time without us knowing. The next time though this function should
- * clip exposure correctly.
+ * exposure time without us knowing. We get around this by ensuring the
+ * staggered write component submits VBLANK separately from, and before the
+ * EXPOSURE control.
*/
ctrls.set(V4L2_CID_VBLANK, vblanking);
ctrls.set(V4L2_CID_EXPOSURE, exposureLines);
@@ -1229,12 +1229,17 @@ int RPiCameraData::configureIPA(const CameraConfiguration *config)
/*
* Setup our staggered control writer with the sensor default
* gain and exposure delays.
+ *
+ * VBLANK must be flagged as "immediate write" to allow it to
+ * be set immediately instead of being batched with all other
+ * controls. This is needed so that any update to the EXPOSURE
+ * control will be validated based on the new VBLANK control value.
*/
if (!staggeredCtrl_) {
staggeredCtrl_.init(unicam_[Unicam::Image].dev(),
- { { V4L2_CID_ANALOGUE_GAIN, result.data[resultIdx++] },
- { V4L2_CID_EXPOSURE, result.data[resultIdx++] },
- { V4L2_CID_VBLANK, result.data[resultIdx++] } });
+ { { V4L2_CID_ANALOGUE_GAIN, result.data[resultIdx++], false },
+ { V4L2_CID_EXPOSURE, result.data[resultIdx++], false },
+ { V4L2_CID_VBLANK, result.data[resultIdx++], true } });
sensorMetadata_ = result.data[resultIdx++];
}
}
@@ -22,21 +22,29 @@ LOG_DEFINE_CATEGORY(RPI_S_W)
namespace RPi {
void StaggeredCtrl::init(V4L2VideoDevice *dev,
- std::initializer_list<std::pair<const uint32_t, uint8_t>> delayList)
+ std::initializer_list<std::tuple<uint32_t, uint8_t, bool>> delayList)
{
std::lock_guard<std::mutex> lock(lock_);
dev_ = dev;
- delay_ = delayList;
+ delay_.clear();
ctrl_.clear();
- /* Find the largest delay across all controls. */
maxDelay_ = 0;
- for (auto const &p : delay_) {
+ for (auto const &c : delayList) {
+ uint32_t id = std::get<0>(c);
+ uint8_t delay = std::get<1>(c);
+ bool immediateWrite = std::get<2>(c);
+
+ delay_[id] = delay;
+ immediateWrite_[id] = immediateWrite;
+
LOG(RPI_S_W, Info) << "Init ctrl "
- << utils::hex(p.first) << " with delay "
- << static_cast<int>(p.second);
- maxDelay_ = std::max(maxDelay_, p.second);
+ << utils::hex(id) << " with delay "
+ << static_cast<int>(delay);
+
+ /* Find the largest delay across all controls. */
+ maxDelay_ = std::max(maxDelay_, delay);
}
init_ = true;
@@ -121,8 +129,21 @@ int StaggeredCtrl::write()
int index = std::max<int>(0, setCount_ - delayDiff);
if (p.second[index].updated) {
- /* We need to write this value out. */
- controls.set(p.first, p.second[index].value);
+ if (immediateWrite_[p.first]) {
+ /*
+ * This control must be written now, it could
+ * affect validity of the other controls.
+ */
+ ControlList immediate(dev_->controls());
+ immediate.set(p.first, p.second[index].value);
+ dev_->setControls(&immediate);
+ } else {
+ /*
+ * Batch up the list of controls and write them
+ * at the end of the function.
+ */
+ controls.set(p.first, p.second[index].value);
+ }
p.second[index].updated = false;
LOG(RPI_S_W, Debug) << "Writing ctrl "
<< utils::hex(p.first) << " to "
@@ -34,7 +34,7 @@ public:
}
void init(V4L2VideoDevice *dev,
- std::initializer_list<std::pair<const uint32_t, uint8_t>> delayList);
+ std::initializer_list<std::tuple<uint32_t, uint8_t, bool>> delayList);
void reset();
void get(std::unordered_map<uint32_t, int32_t> &ctrl, uint8_t offset = 0);
@@ -85,6 +85,7 @@ private:
uint8_t maxDelay_;
V4L2VideoDevice *dev_;
std::unordered_map<uint32_t, uint8_t> delay_;
+ std::unordered_map<uint32_t, bool> immediateWrite_;
std::unordered_map<uint32_t, CircularArray> ctrl_;
std::mutex lock_;
};
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 StaggeredCtrl mark the VBLANK control as "immediate 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. StaggeredCtrl is due to be deprecated and replaced by DelayedCtrl, so this change serves more a working proof-of-concept on the workaround, and not much care has been taken to provide a nice new API for applying this immediate write flag to the control. A similar workaround must be available to DelayedCtrl eventually. Signed-off-by: Naushir Patuck <naush@raspberrypi.com> --- src/ipa/raspberrypi/raspberrypi.cpp | 5 ++- .../pipeline/raspberrypi/raspberrypi.cpp | 11 ++++-- .../pipeline/raspberrypi/staggered_ctrl.cpp | 39 ++++++++++++++----- .../pipeline/raspberrypi/staggered_ctrl.h | 3 +- 4 files changed, 43 insertions(+), 15 deletions(-)