hw/irq.c

   1 /*
   2  * QEMU IRQ/GPIO common code.
   3  *
   4  * Copyright (c) 2007 CodeSourcery.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include "qemu-common.h"
  25 #include "irq.h"
  26
  27 struct IRQState {
  28     qemu_irq_handler handler;
  29     void *opaque;
  30     int n;
  31 };
  32
  33 void qemu_set_irq(qemu_irq irq, int level)
  34 {
  35     if (!irq)
  36         return;
  37
  38     irq->handler(irq->opaque, irq->n, level);
  39 }
  40
  41 qemu_irq *qemu_allocate_irqs(qemu_irq_handler handler, void *opaque, int n)
  42 {
  43     qemu_irq *s;
  44     struct IRQState *p;
  45     int i;
  46
  47     s = (qemu_irq *)qemu_mallocz(sizeof(qemu_irq) * n);
  48     p = (struct IRQState *)qemu_mallocz(sizeof(struct IRQState) * n);
  49     for (i = 0; i < n; i++) {
  50         p->handler = handler;
  51         p->opaque = opaque;
  52         p->n = i;
  53         s[i] = p;
  54         p++;
  55     }
  56     return s;
  57 }
  58
  59 static void qemu_notirq(void *opaque, int line, int level)
  60 {
  61     struct IRQState *irq = opaque;
  62
  63     irq->handler(irq->opaque, irq->n, !level);
  64 }
  65
  66 qemu_irq qemu_irq_invert(qemu_irq irq)
  67 {
  68     /* The default state for IRQs is low, so raise the output now.  */
  69     qemu_irq_raise(irq);
  70     return qemu_allocate_irqs(qemu_notirq, irq, 1)[0];
  71 }