diff --git a/rpcs3/Emu/Cell/Modules/cellOskDialog.cpp b/rpcs3/Emu/Cell/Modules/cellOskDialog.cpp
index 6c4e72f48e..f685f50587 100644
--- a/rpcs3/Emu/Cell/Modules/cellOskDialog.cpp
+++ b/rpcs3/Emu/Cell/Modules/cellOskDialog.cpp
@@ -1,4 +1,4 @@
-#include "stdafx.h"
+#include "stdafx.h"
 #include "Emu/System.h"
 #include "Emu/IdManager.h"
 #include "Emu/Cell/PPUModule.h"
@@ -448,6 +448,12 @@ error_code cellOskDialogDisableDimmer()
 error_code cellOskDialogSetKeyLayoutOption(u32 option)
 {
 	cellOskDialog.todo("cellOskDialogSetKeyLayoutOption(option=0x%x)", option);
+
+	if (option == 0 || option > 3) // CELL_OSKDIALOG_10KEY_PANEL OR CELL_OSKDIALOG_FULLKEY_PANEL
+	{
+		return CELL_OSKDIALOG_ERROR_PARAM;
+	}
+
 	return CELL_OK;
 }
 
@@ -475,16 +481,40 @@ error_code cellOskDialogExtInputDeviceUnlock()
 	return CELL_OK;
 }
 
+error_code register_keyboard_event_hook_callback(u16 hookEventMode, vm::ptr<cellOskDialogHardwareKeyboardEventHookCallback> pCallback)
+{
+	cellOskDialog.todo("register_keyboard_event_hook_callback(hookEventMode=%u, pCallback=*0x%x)", hookEventMode, pCallback);
+
+	if (!pCallback)
+	{
+		return CELL_OSKDIALOG_ERROR_PARAM;
+	}
+
+	return CELL_OK;
+}
+
 error_code cellOskDialogExtRegisterKeyboardEventHookCallback(u16 hookEventMode, vm::ptr<cellOskDialogHardwareKeyboardEventHookCallback> pCallback)
 {
 	cellOskDialog.todo("cellOskDialogExtRegisterKeyboardEventHookCallback(hookEventMode=%u, pCallback=*0x%x)", hookEventMode, pCallback);
-	return CELL_OK;
+
+	if (hookEventMode == 0 || hookEventMode > 3) // CELL_OSKDIALOG_EVENT_HOOK_TYPE_FUNCTION_KEY OR CELL_OSKDIALOG_EVENT_HOOK_TYPE_ASCII_KEY
+	{
+		return CELL_OSKDIALOG_ERROR_PARAM;
+	}
+
+	return register_keyboard_event_hook_callback(hookEventMode, pCallback);
 }
 
 error_code cellOskDialogExtRegisterKeyboardEventHookCallbackEx(u16 hookEventMode, vm::ptr<cellOskDialogHardwareKeyboardEventHookCallback> pCallback)
 {
 	cellOskDialog.todo("cellOskDialogExtRegisterKeyboardEventHookCallbackEx(hookEventMode=%u, pCallback=*0x%x)", hookEventMode, pCallback);
-	return CELL_OK;
+
+	if (hookEventMode == 0 || hookEventMode > 7) // CELL_OSKDIALOG_EVENT_HOOK_TYPE_FUNCTION_KEY OR CELL_OSKDIALOG_EVENT_HOOK_TYPE_ASCII_KEY OR CELL_OSKDIALOG_EVENT_HOOK_TYPE_ONLY_MODIFIER
+	{
+		return CELL_OSKDIALOG_ERROR_PARAM;
+	}
+
+	return register_keyboard_event_hook_callback(hookEventMode, pCallback);
 }
 
 error_code cellOskDialogExtAddJapaneseOptionDictionary(vm::cpptr<char> filePath)
@@ -590,6 +620,12 @@ error_code cellOskDialogExtEnableHalfByteKana()
 error_code cellOskDialogExtRegisterForceFinishCallback(vm::ptr<cellOskDialogForceFinishCallback> pCallback)
 {
 	cellOskDialog.todo("cellOskDialogExtRegisterForceFinishCallback(pCallback=*0x%x)", pCallback);
+
+	if (!pCallback)
+	{
+		return CELL_OSKDIALOG_ERROR_PARAM;
+	}
+
 	return CELL_OK;
 }
 
diff --git a/rpcs3/Emu/Cell/Modules/cellOskDialog.h b/rpcs3/Emu/Cell/Modules/cellOskDialog.h
index f8f0ff61d6..530b8d404a 100644
--- a/rpcs3/Emu/Cell/Modules/cellOskDialog.h
+++ b/rpcs3/Emu/Cell/Modules/cellOskDialog.h
@@ -6,21 +6,21 @@
 enum CellOskDialogError : u32
 {
 	CELL_OSKDIALOG_ERROR_IME_ALREADY_IN_USE = 0x8002b501,
-	CELL_OSKDIALOG_ERROR_GET_SIZE_ERROR = 0x8002b502,
-	CELL_OSKDIALOG_ERROR_UNKNOWN = 0x8002b503,
-	CELL_OSKDIALOG_ERROR_PARAM = 0x8002b504,
+	CELL_OSKDIALOG_ERROR_GET_SIZE_ERROR     = 0x8002b502,
+	CELL_OSKDIALOG_ERROR_UNKNOWN            = 0x8002b503,
+	CELL_OSKDIALOG_ERROR_PARAM              = 0x8002b504,
 };
 
 // OSK status for the callback
 enum
 {
-	CELL_SYSUTIL_OSKDIALOG_LOADED = 0x0502,
-	CELL_SYSUTIL_OSKDIALOG_FINISHED = 0x0503,
-	CELL_SYSUTIL_OSKDIALOG_UNLOADED = 0x0504,
-	CELL_SYSUTIL_OSKDIALOG_INPUT_ENTERED = 0x0505,
-	CELL_SYSUTIL_OSKDIALOG_INPUT_CANCELED = 0x0506,
+	CELL_SYSUTIL_OSKDIALOG_LOADED               = 0x0502,
+	CELL_SYSUTIL_OSKDIALOG_FINISHED             = 0x0503,
+	CELL_SYSUTIL_OSKDIALOG_UNLOADED             = 0x0504,
+	CELL_SYSUTIL_OSKDIALOG_INPUT_ENTERED        = 0x0505,
+	CELL_SYSUTIL_OSKDIALOG_INPUT_CANCELED       = 0x0506,
 	CELL_SYSUTIL_OSKDIALOG_INPUT_DEVICE_CHANGED = 0x0507,
-	CELL_SYSUTIL_OSKDIALOG_DISPLAY_CHANGED = 0x0508,
+	CELL_SYSUTIL_OSKDIALOG_DISPLAY_CHANGED      = 0x0508,
 };
 
 enum CellOskDialogInputFieldResult