ipa: raspberrypi: Limit minimum exposure time for the IMX296

Limit the minimum allowable exposure time to a single line in the IMX296
camera helper. This equates to approximately 30us.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: David Plowman <david.plowman@raspberrypi.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
This commit is contained in:
Naushir Patuck 2022-09-26 10:36:39 +01:00 committed by Laurent Pinchart
parent d476f5e4e2
commit e730867873

View file

@ -26,6 +26,7 @@ public:
void getDelays(int &exposureDelay, int &gainDelay, int &vblankDelay) const override;
private:
static constexpr uint32_t minExposureLines = 1;
static constexpr uint32_t maxGainCode = 239;
static constexpr Duration timePerLine = 550.0 / 37.125e6 * 1.0s;
@ -54,12 +55,12 @@ double CamHelperImx296::gain(uint32_t gainCode) const
uint32_t CamHelperImx296::exposureLines(Duration exposure) const
{
return (exposure - 14.26us) / timePerLine;
return std::max<uint32_t>(minExposureLines, (exposure - 14.26us) / timePerLine);
}
Duration CamHelperImx296::exposure(uint32_t exposureLines) const
{
return exposureLines * timePerLine + 14.26us;
return std::max<uint32_t>(minExposureLines, exposureLines) * timePerLine + 14.26us;
}
void CamHelperImx296::getDelays(int &exposureDelay, int &gainDelay,