ipa: raspberrypi: Generalise the SMIA metadata parser

Instead of having each CamHelper subclass the MdParserSmia, change the
implementation of MdParserSmia to be more generic. The MdParserSmia now gets
given a list of registers to search for and helper functions are used to compute
exposure lines and gain codes from these registers.

Update the imx219 and imx477 CamHelpers by using this new mechanism.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 22 insertions, 100 deletions

diff --git a/src/ipa/raspberrypi/cam_helper_imx477.cpp b/src/ipa/raspberrypi/cam_helper_imx477.cpp
index d72a9be0..4098fde6 100644
--- a/src/ipa/raspberrypi/cam_helper_imx477.cpp
+++ b/src/ipa/raspberrypi/cam_helper_imx477.cpp
@@ -15,21 +15,15 @@
 
 using namespace RPiController;
 
-/* Metadata parser implementation specific to Sony IMX477 sensors. */
-
-class MdParserImx477 : public MdParserSmia
-{
-public:
-	MdParserImx477();
-	Status Parse(libcamera::Span<const uint8_t> buffer) override;
-	Status GetExposureLines(unsigned int &lines) override;
-	Status GetGainCode(unsigned int &gain_code) override;
-private:
-	/* Offset of the register's value in the metadata block. */
-	int reg_offsets_[4];
-	/* Value of the register, once read from the metadata block. */
-	int reg_values_[4];
-};
+/*
+ * We care about two gain registers and a pair of exposure registers. Their
+ * I2C addresses from the Sony IMX477 datasheet:
+ */
+constexpr uint32_t expHiReg = 0x0202;
+constexpr uint32_t expLoReg = 0x0203;
+constexpr uint32_t gainHiReg = 0x0204;
+constexpr uint32_t gainLoReg = 0x0205;
+constexpr std::initializer_list<uint32_t> registerList [[maybe_unused]] = { expHiReg, expLoReg, gainHiReg, gainLoReg };
 
 class CamHelperImx477 : public CamHelper
 {
@@ -47,10 +41,13 @@ private:
 	 * in units of lines.
 	 */
 	static constexpr int frameIntegrationDiff = 22;
+
+	void PopulateMetadata(const MdParser::RegisterMap &registers,
+			      Metadata &metadata) const override;
 };
 
 CamHelperImx477::CamHelperImx477()
-	: CamHelper(std::make_unique<MdParserImx477>(), frameIntegrationDiff)
+	: CamHelper(std::make_unique<MdParserSmia>(registerList), frameIntegrationDiff)
 {
 }
 
@@ -77,95 +74,20 @@ bool CamHelperImx477::SensorEmbeddedDataPresent() const
 	return true;
 }
 
-static CamHelper *Create()
+void CamHelperImx477::PopulateMetadata(const MdParser::RegisterMap &registers,
+				       Metadata &metadata) const
 {
-	return new CamHelperImx477();
-}
+	DeviceStatus deviceStatus;
 
-static RegisterCamHelper reg("imx477", &Create);
+	deviceStatus.shutter_speed = Exposure(registers.at(expHiReg) * 256 + registers.at(expLoReg));
+	deviceStatus.analogue_gain = Gain(registers.at(gainHiReg) * 256 + registers.at(gainLoReg));
 
-/*
- * We care about two gain registers and a pair of exposure registers. Their
- * I2C addresses from the Sony IMX477 datasheet:
- */
-#define EXPHI_REG 0x0202
-#define EXPLO_REG 0x0203
-#define GAINHI_REG 0x0204
-#define GAINLO_REG 0x0205
-
-/*
- * Index of each into the reg_offsets and reg_values arrays. Must be in register
- * address order.
- */
-#define EXPHI_INDEX 0
-#define EXPLO_INDEX 1
-#define GAINHI_INDEX 2
-#define GAINLO_INDEX 3
-
-MdParserImx477::MdParserImx477()
-{
-	reg_offsets_[0] = reg_offsets_[1] = reg_offsets_[2] = reg_offsets_[3] = -1;
+	metadata.Set("device.status", deviceStatus);
 }
 
-MdParser::Status MdParserImx477::Parse(libcamera::Span<const uint8_t> buffer)
-{
-	bool try_again = false;
-
-	if (reset_) {
-		/*
-		 * Search again through the metadata for the gain and exposure
-		 * registers.
-		 */
-		assert(bits_per_pixel_);
-		/* Need to be ordered */
-		uint32_t regs[4] = {
-			EXPHI_REG,
-			EXPLO_REG,
-			GAINHI_REG,
-			GAINLO_REG
-		};
-		reg_offsets_[0] = reg_offsets_[1] = reg_offsets_[2] = reg_offsets_[3] = -1;
-		int ret = static_cast<int>(findRegs(buffer,
-						    regs, reg_offsets_, 4));
-		/*
-		 * > 0 means "worked partially but parse again next time",
-		 * < 0 means "hard error".
-		 */
-		if (ret > 0)
-			try_again = true;
-		else if (ret < 0)
-			return ERROR;
-	}
-
-	for (int i = 0; i < 4; i++) {
-		if (reg_offsets_[i] == -1)
-			continue;
-
-		reg_values_[i] = buffer[reg_offsets_[i]];
-	}
-
-	/* Re-parse next time if we were unhappy in some way. */
-	reset_ = try_again;
-
-	return OK;
-}
-
-MdParser::Status MdParserImx477::GetExposureLines(unsigned int &lines)
+static CamHelper *Create()
 {
-	if (reg_offsets_[EXPHI_INDEX] == -1 || reg_offsets_[EXPLO_INDEX] == -1)
-		return NOTFOUND;
-
-	lines = reg_values_[EXPHI_INDEX] * 256 + reg_values_[EXPLO_INDEX];
-
-	return OK;
+	return new CamHelperImx477();
 }
 
-MdParser::Status MdParserImx477::GetGainCode(unsigned int &gain_code)
-{
-	if (reg_offsets_[GAINHI_INDEX] == -1 || reg_offsets_[GAINLO_INDEX] == -1)
-		return NOTFOUND;
-
-	gain_code = reg_values_[GAINHI_INDEX] * 256 + reg_values_[GAINLO_INDEX];
-
-	return OK;
-}
+static RegisterCamHelper reg("imx477", &Create);