lasips2: add QEMU interface comment

This describes the LASI PS2 device interface implemented within QEMU.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20220624134109.881989-49-mark.cave-ayland@ilande.co.uk>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/include/hw/input/lasips2.h b/include/hw/input/lasips2.h
index 7e4437b..03f0c9e 100644 (file)
--- a/include/hw/input/lasips2.h
+++ b/include/hw/input/lasips2.h
@@ -4,6 +4,20 @@
  * Copyright (c) 2019 Sven Schnelle
  *
  */
+
+/*
+ * QEMU interface:
+ * + sysbus MMIO region 0: MemoryRegion defining the LASI PS2 keyboard
+ *   registers
+ * + sysbus MMIO region 1: MemoryRegion defining the LASI PS2 mouse
+ *   registers
+ * + sysbus IRQ 0: LASI PS2 output irq
+ * + Named GPIO input "ps2-kbd-input-irq": set to 1 if the downstream PS2
+ *   keyboard device has asserted its irq
+ * + Named GPIO input "ps2-mouse-input-irq": set to 1 if the downstream PS2
+ *   mouse device has asserted its irq
+ */
+
 #ifndef HW_INPUT_LASIPS2_H
 #define HW_INPUT_LASIPS2_H