first steps towards (optional) serial mouse support

1 files changed, 7 insertions, 0 deletions

diff --git a/int15ps2.h b/int15ps2.h
index db1b878..04d5a8d 100644
--- a/int15ps2.h
+++ b/int15ps2.h
@@ -23,6 +23,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include "utils.h"
+#include "bda.h"
 
 /** Standard PS/2 mouse IRQ. At least on VirtualBox. */
 #define PS2_MOUSE_IRQ        12
@@ -95,6 +96,12 @@ enum ps2m_sample_rate {
 /** Invoked by the BIOS when there is a mouse event. */
 typedef void (__far * LPFN_PS2CALLBACK)();
 
+static bool ps2m_installed()
+{
+	uint16_t equipment = bda_get_equipment();
+	return equipment & (1 << 2);
+}
+
 static ps2m_err ps2m_init(uint8_t packet_size);
 #pragma aux ps2m_init = \
 	"stc"               /* If nothing happens, assume failure */ \