From 0ebcd2c1c9148e8647a5b2f89654949435403058 Mon Sep 17 00:00:00 2001
From: Javier <dev.git@javispedro.com>
Date: Sun, 13 Mar 2022 00:43:23 +0100
Subject: let VMD know the mouse type

---
 int2fwin.h | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 makefile   |  2 +-
 mousew16.c | 11 ++++++++++-
 ps2.h      |  5 +++++
 4 files changed, 64 insertions(+), 2 deletions(-)

diff --git a/int2fwin.h b/int2fwin.h
index 8d79211..7845293 100644
--- a/int2fwin.h
+++ b/int2fwin.h
@@ -32,6 +32,11 @@ enum int2f_functions
 	INT2F_NOTIFY_FOREGROUND_SWITCH = 0x4002
 };
 
+enum vxd_device_ids
+{
+	VMD_DEVICE_ID = 0xC
+};
+
 static bool windows_386_enhanced_mode(void);
 #pragma aux windows_386_enhanced_mode = \
 	"mov ax, 0x1600" \
@@ -41,6 +46,49 @@ static bool windows_386_enhanced_mode(void);
 	__value [al] \
 	__modify [ax]
 
+static LPFN win_get_vxd_api_entry(uint16_t devid);
+#pragma aux win_get_vxd_api_entry = \
+	"mov ax, 0x1684" /* Get Device Entry Point Address */  \
+	"int 0x2F" \
+	__parm [bx] \
+	__value [es di] \
+	__modify [ax]
+
+/* VMD (Virtual Mouse Device) API */
+
+enum vmd_apis {
+	VMD_GET_VERSION    = 0x0,
+	VMD_SET_MOUSE_TYPE = 0x100,
+};
+
+enum vmd_mouse_type {
+	VMD_TYPE_UNDEFINED = 0,
+	VMD_TYPE_BUS       = 1,
+	VMD_TYPE_SERIAL    = 2,
+	VMD_TYPE_INPORT    = 3,
+	VMD_TYPE_PS2       = 4,
+	VMD_TYPE_HP        = 5
+};
+
+static inline int vmd_get_version(LPFN *vmd_entry);
+#pragma aux vmd_get_version = \
+	"mov ax, 0x000" \
+	"call dword ptr es:[di]" \
+	__parm [es di] \
+	__value [ax]
+
+static inline bool vmd_set_mouse_type(LPFN *vmd_entry, uint8_t mousetype, int8_t interrupt, int8_t com_port);
+#pragma aux vmd_set_mouse_type = \
+	"stc"                    /* If nothing happens, assume failure */ \
+	"mov ax, 0x100" \
+	"call dword ptr es:[di]" \
+	"setnc al" \
+	__parm [es di] [bl] [bh] [cl] \
+	__value [al] \
+	__modify [ax]
+
+/* Miscelaneous helpers. */
+
 static inline void hook_int2f(LPFN *prev, LPFN new)
 {
 	*prev = _dos_getvect(0x2F);
diff --git a/makefile b/makefile
index 9cd59d6..c677d4d 100644
--- a/makefile
+++ b/makefile
@@ -6,7 +6,7 @@
 	set include=$(%watcom)/h/win;$(%watcom)/h
 
 # The main driver file
-vbmouse.drv: mousew16.c mousew16.h vbox.c vbox.h vboxdev.h ps2.h pci.h vds.h
+vbmouse.drv: mousew16.c mousew16.h vbox.c vbox.h vboxdev.h ps2.h pci.h vds.h int2fwin.h
 	# -bd to build DLL
 	# -mc to use compact memory model (far data pointers, since ss != ds)
 	# -zu for DLL calling convention (ss != ds)
diff --git a/mousew16.c b/mousew16.c
index f2e22ab..45c0266 100644
--- a/mousew16.c
+++ b/mousew16.c
@@ -212,6 +212,15 @@ BOOL FAR PASCAL LibMain(HINSTANCE hInstance, WORD wDataSegment,
 	}
 #endif
 
+	// When running under protected mode Windows, let's tell VMD (the mouse virtualizer)
+	// what type of mouse we are going to be using
+	if (mouseflags & MOUSEFLAGS_HAS_WIN386) {
+		LPFN vmd_entry = win_get_vxd_api_entry(VMD_DEVICE_ID);
+		if (vmd_entry) {
+			vmd_set_mouse_type(&vmd_entry, VMD_TYPE_PS2, PS2_MOUSE_INT_VECTOR, 0);
+		}
+	}
+
 	return 1;
 }
 
@@ -317,6 +326,6 @@ VOID FAR PASCAL Disable(VOID)
 /** Called by Window to retrieve the interrupt vector number used by this driver, or -1. */
 int FAR PASCAL MouseGetIntVect(VOID)
 {
-	return 0x74; /* This corresponds to IRQ12, the PS/2 IRQ. At least in VirtualBox. */
+	return PS2_MOUSE_INT_VECTOR;
 }
 
diff --git a/ps2.h b/ps2.h
index 0ff154b..6fcb1ec 100644
--- a/ps2.h
+++ b/ps2.h
@@ -23,6 +23,11 @@
 #include <stdbool.h>
 #include <stdint.h>
 
+/** Standard PS/2 mouse IRQ. At least on VirtualBox. */
+#define PS2_MOUSE_IRQ        12
+/** The corresponding interrupt vector for IRQ 12. */
+#define PS2_MOUSE_INT_VECTOR 0x74
+
 enum {
 	PS2M_STATUS_BUTTON_1 = 1 << 0,
 	PS2M_STATUS_BUTTON_2 = 1 << 1,
-- 
cgit v1.2.3