libcamera: mali-c55: Correct input/output format representation

At present we configure raw streams by looping through the pixel
formats we support and finding one with an associated media bus
format code that the sensor can produce. In the new representation
of raw data from the kernel driver this will not work - the sensor
could produce 8, 10, 12, 14 or 16 bit data and the ISP will force
it to RAW16, which is the only actually supported output.

To fix the issue move to simply finding a pixel format with a bayer
order that matches that of the media bus format produced by the
sensor. If the sensor can produce multiple formats with the same
bayer order use the one with the largest bitdepth.

Finally, remove the claim to support RAW formats of less than 16 bits.

Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>

1 files changed, 85 insertions, 51 deletions

diff --git a/src/libcamera/pipeline/mali-c55/mali-c55.cpp b/src/libcamera/pipeline/mali-c55/mali-c55.cpp
index f5f98c59..e973abc2 100644
--- a/src/libcamera/pipeline/mali-c55/mali-c55.cpp
+++ b/src/libcamera/pipeline/mali-c55/mali-c55.cpp
@@ -57,22 +57,6 @@ const std::map<libcamera::PixelFormat, unsigned int> maliC55FmtToCode = {
 	{ formats::NV21, MEDIA_BUS_FMT_YUV10_1X30 },
 
 	/* RAW formats, FR pipe only. */
-	{ formats::SGBRG8, MEDIA_BUS_FMT_SGBRG8_1X8 },
-	{ formats::SRGGB8, MEDIA_BUS_FMT_SRGGB8_1X8 },
-	{ formats::SBGGR8, MEDIA_BUS_FMT_SBGGR8_1X8 },
-	{ formats::SGRBG8, MEDIA_BUS_FMT_SGRBG8_1X8 },
-	{ formats::SGBRG10, MEDIA_BUS_FMT_SGBRG10_1X10 },
-	{ formats::SRGGB10, MEDIA_BUS_FMT_SRGGB10_1X10 },
-	{ formats::SBGGR10, MEDIA_BUS_FMT_SBGGR10_1X10 },
-	{ formats::SGRBG10, MEDIA_BUS_FMT_SGRBG10_1X10 },
-	{ formats::SGBRG12, MEDIA_BUS_FMT_SGBRG12_1X12 },
-	{ formats::SRGGB12, MEDIA_BUS_FMT_SRGGB12_1X12 },
-	{ formats::SBGGR12, MEDIA_BUS_FMT_SBGGR12_1X12 },
-	{ formats::SGRBG12, MEDIA_BUS_FMT_SGRBG12_1X12 },
-	{ formats::SGBRG14, MEDIA_BUS_FMT_SGBRG14_1X14 },
-	{ formats::SRGGB14, MEDIA_BUS_FMT_SRGGB14_1X14 },
-	{ formats::SBGGR14, MEDIA_BUS_FMT_SBGGR14_1X14 },
-	{ formats::SGRBG14, MEDIA_BUS_FMT_SGRBG14_1X14 },
 	{ formats::SGBRG16, MEDIA_BUS_FMT_SGBRG16_1X16 },
 	{ formats::SRGGB16, MEDIA_BUS_FMT_SRGGB16_1X16 },
 	{ formats::SBGGR16, MEDIA_BUS_FMT_SBGGR16_1X16 },
@@ -98,7 +82,8 @@ public:
 	const std::vector<Size> sizes(unsigned int mbusCode) const;
 	const Size resolution() const;
 
-	PixelFormat bestRawFormat() const;
+	int pixfmtToMbusCode(const PixelFormat &pixFmt) const;
+	const PixelFormat &bestRawFormat() const;
 
 	PixelFormat adjustRawFormat(const PixelFormat &pixFmt) const;
 	Size adjustRawSizes(const PixelFormat &pixFmt, const Size &rawSize) const;
@@ -207,33 +192,78 @@ const Size MaliC55CameraData::resolution() const
 	return tpgResolution_;
 }
 
-PixelFormat MaliC55CameraData::bestRawFormat() const
+/*
+ * The Mali C55 ISP can only produce 16-bit RAW output in bypass modes, but the
+ * sensors connected to it might produce 8/10/12/16 bits. We simply search the
+ * sensor's supported formats for the one with a matching bayer order and the
+ * greatest bitdepth.
+ */
+int MaliC55CameraData::pixfmtToMbusCode(const PixelFormat &pixFmt) const
 {
+	auto it = maliC55FmtToCode.find(pixFmt);
+	if (it == maliC55FmtToCode.end())
+		return -EINVAL;
+
+	BayerFormat bayerFormat = BayerFormat::fromMbusCode(it->second);
+	if (!bayerFormat.isValid())
+		return -EINVAL;
+
+	V4L2Subdevice::Formats formats = sd_->formats(0);
+	unsigned int sensorMbusCode = 0;
 	unsigned int bitDepth = 0;
-	PixelFormat rawFormat;
 
-	/*
-	 * Iterate over all the supported PixelFormat and find the one
-	 * supported by the camera with the largest bitdepth.
-	 */
-	for (const auto &maliFormat : maliC55FmtToCode) {
-		PixelFormat pixFmt = maliFormat.first;
-		if (!isFormatRaw(pixFmt))
+	for (const auto &[code, sizes] : formats) {
+		BayerFormat sdBayerFormat = BayerFormat::fromMbusCode(code);
+		if (!sdBayerFormat.isValid())
 			continue;
 
-		unsigned int rawCode = maliFormat.second;
-		const auto rawSizes = sizes(rawCode);
-		if (rawSizes.empty())
+		if (sdBayerFormat.order != bayerFormat.order)
+			continue;
+
+		if (sdBayerFormat.bitDepth > bitDepth) {
+			bitDepth = sdBayerFormat.bitDepth;
+			sensorMbusCode = code;
+		}
+	}
+
+	if (!sensorMbusCode)
+		return -EINVAL;
+
+	return sensorMbusCode;
+}
+
+/*
+ * Find a RAW PixelFormat supported by both the ISP and the sensor.
+ *
+ * The situation is mildly complicated by the fact that we expect the sensor to
+ * output something like RAW8/10/12/16, but the ISP can only accept as input
+ * RAW20 and can only produce as output RAW16. The one constant in that is the
+ * bayer order of the data, so we'll simply check that the sensor produces a
+ * format with a bayer order that matches that of one of the formats we support,
+ * and select that.
+ */
+const PixelFormat &MaliC55CameraData::bestRawFormat() const
+{
+	static const PixelFormat invalidPixFmt = {};
+
+	for (const auto &fmt : sd_->formats(0)) {
+		BayerFormat sensorBayer = BayerFormat::fromMbusCode(fmt.first);
+
+		if (!sensorBayer.isValid())
 			continue;
 
-		BayerFormat bayer = BayerFormat::fromMbusCode(rawCode);
-		if (bayer.bitDepth > bitDepth) {
-			bitDepth = bayer.bitDepth;
-			rawFormat = pixFmt;
+		for (const auto &[pixFmt, rawCode] : maliC55FmtToCode) {
+			if (!isFormatRaw(pixFmt))
+				continue;
+
+			BayerFormat bayer = BayerFormat::fromMbusCode(rawCode);
+			if (bayer.order == sensorBayer.order)
+				return pixFmt;
 		}
 	}
 
-	return rawFormat;
+	LOG(MaliC55, Error) << "Sensor doesn't provide a compatible format";
+	return invalidPixFmt;
 }
 
 /*
@@ -242,13 +272,11 @@ PixelFormat MaliC55CameraData::bestRawFormat() const
  */
 PixelFormat MaliC55CameraData::adjustRawFormat(const PixelFormat &rawFmt) const
 {
-	/* Make sure the provided raw format is supported by the pipeline. */
-	auto it = maliC55FmtToCode.find(rawFmt);
-	if (it == maliC55FmtToCode.end())
+	/* Make sure the RAW mbus code is supported by the image source. */
+	int rawCode = pixfmtToMbusCode(rawFmt);
+	if (rawCode < 0)
 		return bestRawFormat();
 
-	/* Now make sure the RAW mbus code is supported by the image source. */
-	unsigned int rawCode = it->second;
 	const auto rawSizes = sizes(rawCode);
 	if (rawSizes.empty())
 		return bestRawFormat();
@@ -258,16 +286,14 @@ PixelFormat MaliC55CameraData::adjustRawFormat(const PixelFormat &rawFmt) const
 
 Size MaliC55CameraData::adjustRawSizes(const PixelFormat &rawFmt, const Size &size) const
 {
-	/* Just make sure the format is supported. */
-	auto it = maliC55FmtToCode.find(rawFmt);
-	if (it == maliC55FmtToCode.end())
-		return {};
-
 	/* Expand the RAW size to the minimum ISP input size. */
 	Size rawSize = size.expandedTo(kMaliC55MinInputSize);
 
 	/* Check if the size is natively supported. */
-	unsigned int rawCode = it->second;
+	int rawCode = pixfmtToMbusCode(rawFmt);
+	if (rawCode < 0)
+		return {};
+
 	const auto rawSizes = sizes(rawCode);
 	auto sizeIt = std::find(rawSizes.begin(), rawSizes.end(), rawSize);
 	if (sizeIt != rawSizes.end())
@@ -348,6 +374,10 @@ CameraConfiguration::Status MaliC55CameraConfiguration::validate()
 		 */
 		PixelFormat rawFormat =
 			data_->adjustRawFormat(rawConfig->pixelFormat);
+
+		if (!rawFormat.isValid())
+			return Invalid;
+
 		if (rawFormat != rawConfig->pixelFormat) {
 			LOG(MaliC55, Debug)
 				<< "RAW format adjusted to " << rawFormat;
@@ -417,8 +447,7 @@ CameraConfiguration::Status MaliC55CameraConfiguration::validate()
 
 	/* If there's a RAW config, sensor configuration follows it. */
 	if (rawConfig) {
-		const auto it = maliC55FmtToCode.find(rawConfig->pixelFormat);
-		sensorFormat_.code = it->second;
+		sensorFormat_.code = data_->pixfmtToMbusCode(rawConfig->pixelFormat);
 		sensorFormat_.size = rawConfig->size.expandedTo(minSensorSize);
 
 		return status;
@@ -426,11 +455,13 @@ CameraConfiguration::Status MaliC55CameraConfiguration::validate()
 
 	/* If there's no RAW config, compute the sensor configuration here. */
 	PixelFormat rawFormat = data_->bestRawFormat();
-	const auto it = maliC55FmtToCode.find(rawFormat);
-	sensorFormat_.code = it->second;
+	if (!rawFormat.isValid())
+		return Invalid;
+
+	sensorFormat_.code = data_->pixfmtToMbusCode(rawFormat);
 
 	uint16_t distance = std::numeric_limits<uint16_t>::max();
-	const auto sizes = data_->sizes(it->second);
+	const auto sizes = data_->sizes(sensorFormat_.code);
 	Size bestSize;
 	for (const auto &size : sizes) {
 		if (minSensorSize.width > size.width ||
@@ -613,7 +644,10 @@ PipelineHandlerMaliC55::generateConfiguration(Camera *camera,
 
 			if (isRaw) {
 				/* Make sure the mbus code is supported. */
-				unsigned int rawCode = maliFormat.second;
+				int rawCode = data->pixfmtToMbusCode(pixFmt);
+				if (rawCode < 0)
+					continue;
+
 				const auto sizes = data->sizes(rawCode);
 				if (sizes.empty())
 					continue;