From 76a14b3bae409c268e76daf721962136b690aa7e Mon Sep 17 00:00:00 2001
From: wheremyfoodat <44909372+wheremyfoodat@users.noreply.github.com>
Date: Tue, 23 Jan 2024 19:20:56 +0200
Subject: [PATCH] Implement CAM::GetMaxBytes/SetTransferBytes

---
 include/services/cam.hpp  |  2 ++
 src/core/services/cam.cpp | 49 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/include/services/cam.hpp b/include/services/cam.hpp
index 5ef3edba..60ede3b9 100644
--- a/include/services/cam.hpp
+++ b/include/services/cam.hpp
@@ -37,6 +37,7 @@ class CAMService {
 	// Service commands
 	void driverInitialize(u32 messagePointer);
 	void driverFinalize(u32 messagePointer);
+	void getMaxBytes(u32 messagePointer);
 	void getMaxLines(u32 messagePointer);
 	void getBufferErrorInterruptEvent(u32 messagePointer);
 	void getSuitableY2RCoefficients(u32 messagePointer);
@@ -45,6 +46,7 @@ class CAMService {
 	void setFrameRate(u32 messagePointer);
 	void setReceiving(u32 messagePointer);
 	void setSize(u32 messagePointer);
+	void setTransferBytes(u32 messagePointer);
 	void setTransferLines(u32 messagePointer);
 	void setTrimming(u32 messagePointer);
 	void setTrimmingParamsCenter(u32 messagePointer);
diff --git a/src/core/services/cam.cpp b/src/core/services/cam.cpp
index e617ef2f..b3dfd1dc 100644
--- a/src/core/services/cam.cpp
+++ b/src/core/services/cam.cpp
@@ -14,7 +14,9 @@ namespace CAMCommands {
 		DriverFinalize = 0x003A0000,
 		SetTransferLines = 0x00090100,
 		GetMaxLines = 0x000A0080,
+		SetTransferBytes = 0x000B0100,
 		GetTransferBytes = 0x000C0040,
+		GetMaxBytes = 0x000D0080,
 		SetTrimming = 0x000E0080,
 		SetTrimmingParamsCenter = 0x00120140,
 		SetSize = 0x001F00C0,  // Set size has different headers between cam:u and New3DS QTM module
@@ -73,6 +75,7 @@ void CAMService::handleSyncRequest(u32 messagePointer) {
 		case CAMCommands::DriverInitialize: driverInitialize(messagePointer); break;
 		case CAMCommands::DriverFinalize: driverFinalize(messagePointer); break;
 		case CAMCommands::GetBufferErrorInterruptEvent: getBufferErrorInterruptEvent(messagePointer); break;
+		case CAMCommands::GetMaxBytes: getMaxBytes(messagePointer); break;
 		case CAMCommands::GetMaxLines: getMaxLines(messagePointer); break;
 		case CAMCommands::GetSuitableY2rStandardCoefficient: getSuitableY2RCoefficients(messagePointer); break;
 		case CAMCommands::GetTransferBytes: getTransferBytes(messagePointer); break;
@@ -87,7 +90,7 @@ void CAMService::handleSyncRequest(u32 messagePointer) {
 
 		default:
 			Helpers::warn("Unimplemented CAM service requested. Command: %08X\n", command);
-			mem.write32(messagePointer + 4, 0);
+			mem.write32(messagePointer + 4, Result::Success);
 			break;
 	}
 }
@@ -114,6 +117,28 @@ void CAMService::setContrast(u32 messagePointer) {
 	mem.write32(messagePointer + 4, Result::Success);
 }
 
+void CAMService::setTransferBytes(u32 messagePointer) {
+	const u32 portIndex = mem.read8(messagePointer + 4);
+	const u32 bytes = mem.read16(messagePointer + 8);
+	// ...why do these parameters even exist?
+	const u16 width = mem.read16(messagePointer + 12);
+	const u16 height = mem.read16(messagePointer + 16);
+	const PortSelect port(portIndex);
+
+	if (port.isValid()) {
+		for (int i : port.getPortIndices()) {
+			ports[i].transferBytes = bytes;
+		}
+	} else {
+		Helpers::warn("CAM::SetTransferBytes: Invalid port\n");
+	}
+
+	log("CAM::SetTransferBytes (port = %d, bytes = %d, width = %d, height = %d)\n", portIndex, bytes, width, height);
+
+	mem.write32(messagePointer, IPC::responseHeader(0x9, 1, 0));
+	mem.write32(messagePointer + 4, Result::Success);
+}
+
 void CAMService::setTransferLines(u32 messagePointer) {
 	const u32 portIndex = mem.read8(messagePointer + 4);
 	const u16 lines = mem.read16(messagePointer + 8);
@@ -214,6 +239,28 @@ void CAMService::getMaxLines(u32 messagePointer) {
 	}
 }
 
+void CAMService::getMaxBytes(u32 messagePointer) {
+	const u16 width = mem.read16(messagePointer + 4);
+	const u16 height = mem.read16(messagePointer + 8);
+	log("CAM::GetMaxBytes (width = %d, height = %d)\n", width, height);
+
+	constexpr u32 MIN_TRANSFER_UNIT = 256;
+	constexpr u32 MAX_BUFFER_SIZE = 2560;
+	if (width * height * 2 % MIN_TRANSFER_UNIT != 0) {
+		Helpers::panic("CAM::GetMaxLines out of range");
+	} else {
+		u32 bytes = MAX_BUFFER_SIZE;
+
+		while (width * height * 2 % bytes != 0) {
+			bytes -= MIN_TRANSFER_UNIT;
+		}
+
+		mem.write32(messagePointer, IPC::responseHeader(0xA, 2, 0));
+		mem.write32(messagePointer + 4, Result::Success);
+		mem.write32(messagePointer + 8, bytes);
+	}
+}
+
 void CAMService::getSuitableY2RCoefficients(u32 messagePointer) {
 	log("CAM::GetSuitableY2RCoefficients\n");
 	mem.write32(messagePointer, IPC::responseHeader(0x36, 2, 0));