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diff --git a/hw/parallel.c b/hw/parallel.c
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+/*
+ * QEMU Parallel PORT emulation
+ *
+ * Copyright (c) 2003-2004 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "vl.h"
+
+//#define DEBUG_PARALLEL
+
+/*
+ * These are the definitions for the Printer Status Register
+ */
+#define PARA_STS_BUSY 0x80 /* Busy complement */
+#define PARA_STS_ACK 0x40 /* Acknowledge */
+#define PARA_STS_PAPER 0x20 /* Out of paper */
+#define PARA_STS_ONLINE 0x10 /* Online */
+#define PARA_STS_ERROR 0x08 /* Error complement */
+
+/*
+ * These are the definitions for the Printer Control Register
+ */
+#define PARA_CTR_INTEN 0x10 /* IRQ Enable */
+#define PARA_CTR_SELECT 0x08 /* Select In complement */
+#define PARA_CTR_INIT 0x04 /* Initialize Printer complement */
+#define PARA_CTR_AUTOLF 0x02 /* Auto linefeed complement */
+#define PARA_CTR_STROBE 0x01 /* Strobe complement */
+
+struct ParallelState {
+ uint8_t data;
+ uint8_t status; /* read only register */
+ uint8_t control;
+ int irq;
+ int irq_pending;
+ CharDriverState *chr;
+};
+
+static void parallel_update_irq(ParallelState *s)
+{
+ if (s->irq_pending)
+ pic_set_irq(s->irq, 1);
+ else
+ pic_set_irq(s->irq, 0);
+}
+
+static void parallel_ioport_write(void *opaque, uint32_t addr, uint32_t val)
+{
+ ParallelState *s = opaque;
+
+ addr &= 7;
+#ifdef DEBUG_PARALLEL
+ printf("parallel: write addr=0x%02x val=0x%02x\n", addr, val);
+#endif
+ switch(addr) {
+ case 0:
+ s->data = val;
+ parallel_update_irq(s);
+ break;
+ case 2:
+ if ((val & PARA_CTR_INIT) == 0 ) {
+ s->status = PARA_STS_BUSY;
+ s->status |= PARA_STS_ACK;
+ s->status |= PARA_STS_ONLINE;
+ s->status |= PARA_STS_ERROR;
+ }
+ else if (val & PARA_CTR_SELECT) {
+ if (val & PARA_CTR_STROBE) {
+ s->status &= ~PARA_STS_BUSY;
+ if ((s->control & PARA_CTR_STROBE) == 0)
+ qemu_chr_write(s->chr, &s->data, 1);
+ } else {
+ if (s->control & PARA_CTR_INTEN) {
+ s->irq_pending = 1;
+ }
+ }
+ }
+ parallel_update_irq(s);
+ s->control = val;
+ break;
+ }
+}
+
+static uint32_t parallel_ioport_read(void *opaque, uint32_t addr)
+{
+ ParallelState *s = opaque;
+ uint32_t ret = 0xff;
+
+ addr &= 7;
+ switch(addr) {
+ case 0:
+ ret = s->data;
+ break;
+ case 1:
+ ret = s->status;
+ s->irq_pending = 0;
+ if ((s->status & PARA_STS_BUSY) == 0 && (s->control & PARA_CTR_STROBE) == 0) {
+ /* XXX Fixme: wait 5 microseconds */
+ if (s->status & PARA_STS_ACK)
+ s->status &= ~PARA_STS_ACK;
+ else {
+ /* XXX Fixme: wait 5 microseconds */
+ s->status |= PARA_STS_ACK;
+ s->status |= PARA_STS_BUSY;
+ }
+ }
+ parallel_update_irq(s);
+ break;
+ case 2:
+ ret = s->control;
+ break;
+ }
+#ifdef DEBUG_PARALLEL
+ printf("parallel: read addr=0x%02x val=0x%02x\n", addr, ret);
+#endif
+ return ret;
+}
+
+static int parallel_can_receive(ParallelState *s)
+{
+ return 0;
+}
+
+static void parallel_receive_byte(ParallelState *s, int ch)
+{
+}
+
+static void parallel_receive_break(ParallelState *s)
+{
+}
+
+static int parallel_can_receive1(void *opaque)
+{
+ ParallelState *s = opaque;
+ return parallel_can_receive(s);
+}
+
+static void parallel_receive1(void *opaque, const uint8_t *buf, int size)
+{
+ ParallelState *s = opaque;
+ parallel_receive_byte(s, buf[0]);
+}
+
+static void parallel_event(void *opaque, int event)
+{
+ ParallelState *s = opaque;
+}
+
+/* If fd is zero, it means that the parallel device uses the console */
+ParallelState *parallel_init(int base, int irq, CharDriverState *chr)
+{
+ ParallelState *s;
+
+ s = qemu_mallocz(sizeof(ParallelState));
+ if (!s)
+ return NULL;
+ s->irq = irq;
+ s->data = 0;
+ s->status = PARA_STS_BUSY;
+ s->status |= PARA_STS_ACK;
+ s->status |= PARA_STS_ONLINE;
+ s->status |= PARA_STS_ERROR;
+ s->control = PARA_CTR_SELECT;
+ s->control |= PARA_CTR_INIT;
+
+ register_ioport_write(base, 8, 1, parallel_ioport_write, s);
+ register_ioport_read(base, 8, 1, parallel_ioport_read, s);
+ s->chr = chr;
+ qemu_chr_add_read_handler(chr, parallel_can_receive1, parallel_receive1, s);
+ qemu_chr_add_event_handler(chr, parallel_event);
+ return s;
+}