hw/input/stellaris_input.c

   1 /*
   2  * Gamepad style buttons connected to IRQ/GPIO lines
   3  *
   4  * Copyright (c) 2007 CodeSourcery.
   5  * Written by Paul Brook
   6  *
   7  * This code is licensed under the GPL.
   8  */
   9 #include "qemu/osdep.h"
  10 #include "hw/hw.h"
  11 #include "hw/devices.h"
  12 #include "ui/console.h"
  13
  14 typedef struct {
  15     qemu_irq irq;
  16     int keycode;
  17     uint8_t pressed;
  18 } gamepad_button;
  19
  20 typedef struct {
  21     gamepad_button *buttons;
  22     int num_buttons;
  23     int extension;
  24 } gamepad_state;
  25
  26 static void stellaris_gamepad_put_key(void * opaque, int keycode)
  27 {
  28     gamepad_state *s = (gamepad_state *)opaque;
  29     int i;
  30     int down;
  31
  32     if (keycode == 0xe0 && !s->extension) {
  33         s->extension = 0x80;
  34         return;
  35     }
  36
  37     down = (keycode & 0x80) == 0;
  38     keycode = (keycode & 0x7f) | s->extension;
  39
  40     for (i = 0; i < s->num_buttons; i++) {
  41         if (s->buttons[i].keycode == keycode
  42                 && s->buttons[i].pressed != down) {
  43             s->buttons[i].pressed = down;
  44             qemu_set_irq(s->buttons[i].irq, down);
  45         }
  46     }
  47
  48     s->extension = 0;
  49 }
  50
  51 static const VMStateDescription vmstate_stellaris_button = {
  52     .name = "stellaris_button",
  53     .version_id = 0,
  54     .minimum_version_id = 0,
  55     .fields = (VMStateField[]) {
  56         VMSTATE_UINT8(pressed, gamepad_button),
  57         VMSTATE_END_OF_LIST()
  58     }
  59 };
  60
  61 static const VMStateDescription vmstate_stellaris_gamepad = {
  62     .name = "stellaris_gamepad",
  63     .version_id = 1,
  64     .minimum_version_id = 1,
  65     .fields = (VMStateField[]) {
  66         VMSTATE_INT32(extension, gamepad_state),
  67         VMSTATE_STRUCT_VARRAY_INT32(buttons, gamepad_state, num_buttons, 0,
  68                               vmstate_stellaris_button, gamepad_button),
  69         VMSTATE_END_OF_LIST()
  70     }
  71 };
  72
  73 /* Returns an array of 5 output slots.  */
  74 void stellaris_gamepad_init(int n, qemu_irq *irq, const int *keycode)
  75 {
  76     gamepad_state *s;
  77     int i;
  78
  79     s = g_new0(gamepad_state, 1);
  80     s->buttons = g_new0(gamepad_button, n);
  81     for (i = 0; i < n; i++) {
  82         s->buttons[i].irq = irq[i];
  83         s->buttons[i].keycode = keycode[i];
  84     }
  85     s->num_buttons = n;
  86     qemu_add_kbd_event_handler(stellaris_gamepad_put_key, s);
  87     vmstate_register(NULL, -1, &vmstate_stellaris_gamepad, s);
  88 }