xref: /openbmc/qemu/hw/char/parallel.c (revision 93e0932b)
1 /*
2  * QEMU Parallel PORT emulation
3  *
4  * Copyright (c) 2003-2005 Fabrice Bellard
5  * Copyright (c) 2007 Marko Kohtala
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "qapi/error.h"
28 #include "qemu/module.h"
29 #include "chardev/char-parallel.h"
30 #include "chardev/char-fe.h"
31 #include "hw/acpi/acpi_aml_interface.h"
32 #include "hw/irq.h"
33 #include "hw/isa/isa.h"
34 #include "hw/qdev-properties.h"
35 #include "hw/qdev-properties-system.h"
36 #include "migration/vmstate.h"
37 #include "hw/char/parallel.h"
38 #include "sysemu/reset.h"
39 #include "sysemu/sysemu.h"
40 #include "trace.h"
41 #include "qom/object.h"
42 
43 //#define DEBUG_PARALLEL
44 
45 #ifdef DEBUG_PARALLEL
46 #define pdebug(fmt, ...) printf("pp: " fmt, ## __VA_ARGS__)
47 #else
48 #define pdebug(fmt, ...) ((void)0)
49 #endif
50 
51 #define PARA_REG_DATA 0
52 #define PARA_REG_STS 1
53 #define PARA_REG_CTR 2
54 #define PARA_REG_EPP_ADDR 3
55 #define PARA_REG_EPP_DATA 4
56 
57 /*
58  * These are the definitions for the Printer Status Register
59  */
60 #define PARA_STS_BUSY	0x80	/* Busy complement */
61 #define PARA_STS_ACK	0x40	/* Acknowledge */
62 #define PARA_STS_PAPER	0x20	/* Out of paper */
63 #define PARA_STS_ONLINE	0x10	/* Online */
64 #define PARA_STS_ERROR	0x08	/* Error complement */
65 #define PARA_STS_TMOUT	0x01	/* EPP timeout */
66 
67 /*
68  * These are the definitions for the Printer Control Register
69  */
70 #define PARA_CTR_DIR	0x20	/* Direction (1=read, 0=write) */
71 #define PARA_CTR_INTEN	0x10	/* IRQ Enable */
72 #define PARA_CTR_SELECT	0x08	/* Select In complement */
73 #define PARA_CTR_INIT	0x04	/* Initialize Printer complement */
74 #define PARA_CTR_AUTOLF	0x02	/* Auto linefeed complement */
75 #define PARA_CTR_STROBE	0x01	/* Strobe complement */
76 
77 #define PARA_CTR_SIGNAL (PARA_CTR_SELECT|PARA_CTR_INIT|PARA_CTR_AUTOLF|PARA_CTR_STROBE)
78 
79 typedef struct ParallelState {
80     MemoryRegion iomem;
81     uint8_t dataw;
82     uint8_t datar;
83     uint8_t status;
84     uint8_t control;
85     qemu_irq irq;
86     int irq_pending;
87     CharBackend chr;
88     int hw_driver;
89     int epp_timeout;
90     uint32_t last_read_offset; /* For debugging */
91     /* Memory-mapped interface */
92     int it_shift;
93     PortioList portio_list;
94 } ParallelState;
95 
96 #define TYPE_ISA_PARALLEL "isa-parallel"
97 OBJECT_DECLARE_SIMPLE_TYPE(ISAParallelState, ISA_PARALLEL)
98 
99 struct ISAParallelState {
100     ISADevice parent_obj;
101 
102     uint32_t index;
103     uint32_t iobase;
104     uint32_t isairq;
105     ParallelState state;
106 };
107 
108 static void parallel_update_irq(ParallelState *s)
109 {
110     if (s->irq_pending)
111         qemu_irq_raise(s->irq);
112     else
113         qemu_irq_lower(s->irq);
114 }
115 
116 static void
117 parallel_ioport_write_sw(void *opaque, uint32_t addr, uint32_t val)
118 {
119     ParallelState *s = opaque;
120 
121     addr &= 7;
122     trace_parallel_ioport_write("SW", addr, val);
123     switch(addr) {
124     case PARA_REG_DATA:
125         s->dataw = val;
126         parallel_update_irq(s);
127         break;
128     case PARA_REG_CTR:
129         val |= 0xc0;
130         if ((val & PARA_CTR_INIT) == 0 ) {
131             s->status = PARA_STS_BUSY;
132             s->status |= PARA_STS_ACK;
133             s->status |= PARA_STS_ONLINE;
134             s->status |= PARA_STS_ERROR;
135         }
136         else if (val & PARA_CTR_SELECT) {
137             if (val & PARA_CTR_STROBE) {
138                 s->status &= ~PARA_STS_BUSY;
139                 if ((s->control & PARA_CTR_STROBE) == 0)
140                     /* XXX this blocks entire thread. Rewrite to use
141                      * qemu_chr_fe_write and background I/O callbacks */
142                     qemu_chr_fe_write_all(&s->chr, &s->dataw, 1);
143             } else {
144                 if (s->control & PARA_CTR_INTEN) {
145                     s->irq_pending = 1;
146                 }
147             }
148         }
149         parallel_update_irq(s);
150         s->control = val;
151         break;
152     }
153 }
154 
155 static void parallel_ioport_write_hw(void *opaque, uint32_t addr, uint32_t val)
156 {
157     ParallelState *s = opaque;
158     uint8_t parm = val;
159     int dir;
160 
161     /* Sometimes programs do several writes for timing purposes on old
162        HW. Take care not to waste time on writes that do nothing. */
163 
164     s->last_read_offset = ~0U;
165 
166     addr &= 7;
167     trace_parallel_ioport_write("HW", addr, val);
168     switch(addr) {
169     case PARA_REG_DATA:
170         if (s->dataw == val)
171             return;
172         pdebug("wd%02x\n", val);
173         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_WRITE_DATA, &parm);
174         s->dataw = val;
175         break;
176     case PARA_REG_STS:
177         pdebug("ws%02x\n", val);
178         if (val & PARA_STS_TMOUT)
179             s->epp_timeout = 0;
180         break;
181     case PARA_REG_CTR:
182         val |= 0xc0;
183         if (s->control == val)
184             return;
185         pdebug("wc%02x\n", val);
186 
187         if ((val & PARA_CTR_DIR) != (s->control & PARA_CTR_DIR)) {
188             if (val & PARA_CTR_DIR) {
189                 dir = 1;
190             } else {
191                 dir = 0;
192             }
193             qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_DATA_DIR, &dir);
194             parm &= ~PARA_CTR_DIR;
195         }
196 
197         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_WRITE_CONTROL, &parm);
198         s->control = val;
199         break;
200     case PARA_REG_EPP_ADDR:
201         if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT)
202             /* Controls not correct for EPP address cycle, so do nothing */
203             pdebug("wa%02x s\n", val);
204         else {
205             struct ParallelIOArg ioarg = { .buffer = &parm, .count = 1 };
206             if (qemu_chr_fe_ioctl(&s->chr,
207                                   CHR_IOCTL_PP_EPP_WRITE_ADDR, &ioarg)) {
208                 s->epp_timeout = 1;
209                 pdebug("wa%02x t\n", val);
210             }
211             else
212                 pdebug("wa%02x\n", val);
213         }
214         break;
215     case PARA_REG_EPP_DATA:
216         if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT)
217             /* Controls not correct for EPP data cycle, so do nothing */
218             pdebug("we%02x s\n", val);
219         else {
220             struct ParallelIOArg ioarg = { .buffer = &parm, .count = 1 };
221             if (qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg)) {
222                 s->epp_timeout = 1;
223                 pdebug("we%02x t\n", val);
224             }
225             else
226                 pdebug("we%02x\n", val);
227         }
228         break;
229     }
230 }
231 
232 static void
233 parallel_ioport_eppdata_write_hw2(void *opaque, uint32_t addr, uint32_t val)
234 {
235     ParallelState *s = opaque;
236     uint16_t eppdata = cpu_to_le16(val);
237     int err;
238     struct ParallelIOArg ioarg = {
239         .buffer = &eppdata, .count = sizeof(eppdata)
240     };
241 
242     trace_parallel_ioport_write("EPP", addr, val);
243     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT) {
244         /* Controls not correct for EPP data cycle, so do nothing */
245         pdebug("we%04x s\n", val);
246         return;
247     }
248     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg);
249     if (err) {
250         s->epp_timeout = 1;
251         pdebug("we%04x t\n", val);
252     }
253     else
254         pdebug("we%04x\n", val);
255 }
256 
257 static void
258 parallel_ioport_eppdata_write_hw4(void *opaque, uint32_t addr, uint32_t val)
259 {
260     ParallelState *s = opaque;
261     uint32_t eppdata = cpu_to_le32(val);
262     int err;
263     struct ParallelIOArg ioarg = {
264         .buffer = &eppdata, .count = sizeof(eppdata)
265     };
266 
267     trace_parallel_ioport_write("EPP", addr, val);
268     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT) {
269         /* Controls not correct for EPP data cycle, so do nothing */
270         pdebug("we%08x s\n", val);
271         return;
272     }
273     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg);
274     if (err) {
275         s->epp_timeout = 1;
276         pdebug("we%08x t\n", val);
277     }
278     else
279         pdebug("we%08x\n", val);
280 }
281 
282 static uint32_t parallel_ioport_read_sw(void *opaque, uint32_t addr)
283 {
284     ParallelState *s = opaque;
285     uint32_t ret = 0xff;
286 
287     addr &= 7;
288     switch(addr) {
289     case PARA_REG_DATA:
290         if (s->control & PARA_CTR_DIR)
291             ret = s->datar;
292         else
293             ret = s->dataw;
294         break;
295     case PARA_REG_STS:
296         ret = s->status;
297         s->irq_pending = 0;
298         if ((s->status & PARA_STS_BUSY) == 0 && (s->control & PARA_CTR_STROBE) == 0) {
299             /* XXX Fixme: wait 5 microseconds */
300             if (s->status & PARA_STS_ACK)
301                 s->status &= ~PARA_STS_ACK;
302             else {
303                 /* XXX Fixme: wait 5 microseconds */
304                 s->status |= PARA_STS_ACK;
305                 s->status |= PARA_STS_BUSY;
306             }
307         }
308         parallel_update_irq(s);
309         break;
310     case PARA_REG_CTR:
311         ret = s->control;
312         break;
313     }
314     trace_parallel_ioport_read("SW", addr, ret);
315     return ret;
316 }
317 
318 static uint32_t parallel_ioport_read_hw(void *opaque, uint32_t addr)
319 {
320     ParallelState *s = opaque;
321     uint8_t ret = 0xff;
322     addr &= 7;
323     switch(addr) {
324     case PARA_REG_DATA:
325         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_DATA, &ret);
326         if (s->last_read_offset != addr || s->datar != ret)
327             pdebug("rd%02x\n", ret);
328         s->datar = ret;
329         break;
330     case PARA_REG_STS:
331         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_STATUS, &ret);
332         ret &= ~PARA_STS_TMOUT;
333         if (s->epp_timeout)
334             ret |= PARA_STS_TMOUT;
335         if (s->last_read_offset != addr || s->status != ret)
336             pdebug("rs%02x\n", ret);
337         s->status = ret;
338         break;
339     case PARA_REG_CTR:
340         /* s->control has some bits fixed to 1. It is zero only when
341            it has not been yet written to.  */
342         if (s->control == 0) {
343             qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_CONTROL, &ret);
344             if (s->last_read_offset != addr)
345                 pdebug("rc%02x\n", ret);
346             s->control = ret;
347         }
348         else {
349             ret = s->control;
350             if (s->last_read_offset != addr)
351                 pdebug("rc%02x\n", ret);
352         }
353         break;
354     case PARA_REG_EPP_ADDR:
355         if ((s->control & (PARA_CTR_DIR | PARA_CTR_SIGNAL)) !=
356             (PARA_CTR_DIR | PARA_CTR_INIT))
357             /* Controls not correct for EPP addr cycle, so do nothing */
358             pdebug("ra%02x s\n", ret);
359         else {
360             struct ParallelIOArg ioarg = { .buffer = &ret, .count = 1 };
361             if (qemu_chr_fe_ioctl(&s->chr,
362                                   CHR_IOCTL_PP_EPP_READ_ADDR, &ioarg)) {
363                 s->epp_timeout = 1;
364                 pdebug("ra%02x t\n", ret);
365             }
366             else
367                 pdebug("ra%02x\n", ret);
368         }
369         break;
370     case PARA_REG_EPP_DATA:
371         if ((s->control & (PARA_CTR_DIR | PARA_CTR_SIGNAL)) !=
372             (PARA_CTR_DIR | PARA_CTR_INIT))
373             /* Controls not correct for EPP data cycle, so do nothing */
374             pdebug("re%02x s\n", ret);
375         else {
376             struct ParallelIOArg ioarg = { .buffer = &ret, .count = 1 };
377             if (qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg)) {
378                 s->epp_timeout = 1;
379                 pdebug("re%02x t\n", ret);
380             }
381             else
382                 pdebug("re%02x\n", ret);
383         }
384         break;
385     }
386     trace_parallel_ioport_read("HW", addr, ret);
387     s->last_read_offset = addr;
388     return ret;
389 }
390 
391 static uint32_t
392 parallel_ioport_eppdata_read_hw2(void *opaque, uint32_t addr)
393 {
394     ParallelState *s = opaque;
395     uint32_t ret;
396     uint16_t eppdata = ~0;
397     int err;
398     struct ParallelIOArg ioarg = {
399         .buffer = &eppdata, .count = sizeof(eppdata)
400     };
401     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT)) {
402         /* Controls not correct for EPP data cycle, so do nothing */
403         pdebug("re%04x s\n", eppdata);
404         return eppdata;
405     }
406     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg);
407     ret = le16_to_cpu(eppdata);
408 
409     if (err) {
410         s->epp_timeout = 1;
411         pdebug("re%04x t\n", ret);
412     }
413     else
414         pdebug("re%04x\n", ret);
415     trace_parallel_ioport_read("EPP", addr, ret);
416     return ret;
417 }
418 
419 static uint32_t
420 parallel_ioport_eppdata_read_hw4(void *opaque, uint32_t addr)
421 {
422     ParallelState *s = opaque;
423     uint32_t ret;
424     uint32_t eppdata = ~0U;
425     int err;
426     struct ParallelIOArg ioarg = {
427         .buffer = &eppdata, .count = sizeof(eppdata)
428     };
429     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT)) {
430         /* Controls not correct for EPP data cycle, so do nothing */
431         pdebug("re%08x s\n", eppdata);
432         return eppdata;
433     }
434     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg);
435     ret = le32_to_cpu(eppdata);
436 
437     if (err) {
438         s->epp_timeout = 1;
439         pdebug("re%08x t\n", ret);
440     }
441     else
442         pdebug("re%08x\n", ret);
443     trace_parallel_ioport_read("EPP", addr, ret);
444     return ret;
445 }
446 
447 static void parallel_ioport_ecp_write(void *opaque, uint32_t addr, uint32_t val)
448 {
449     trace_parallel_ioport_write("ECP", addr & 7, val);
450     pdebug("wecp%d=%02x\n", addr & 7, val);
451 }
452 
453 static uint32_t parallel_ioport_ecp_read(void *opaque, uint32_t addr)
454 {
455     uint8_t ret = 0xff;
456 
457     trace_parallel_ioport_read("ECP", addr & 7, ret);
458     pdebug("recp%d:%02x\n", addr & 7, ret);
459     return ret;
460 }
461 
462 static void parallel_reset(void *opaque)
463 {
464     ParallelState *s = opaque;
465 
466     s->datar = ~0;
467     s->dataw = ~0;
468     s->status = PARA_STS_BUSY;
469     s->status |= PARA_STS_ACK;
470     s->status |= PARA_STS_ONLINE;
471     s->status |= PARA_STS_ERROR;
472     s->status |= PARA_STS_TMOUT;
473     s->control = PARA_CTR_SELECT;
474     s->control |= PARA_CTR_INIT;
475     s->control |= 0xc0;
476     s->irq_pending = 0;
477     s->hw_driver = 0;
478     s->epp_timeout = 0;
479     s->last_read_offset = ~0U;
480 }
481 
482 static const int isa_parallel_io[MAX_PARALLEL_PORTS] = { 0x378, 0x278, 0x3bc };
483 
484 static const MemoryRegionPortio isa_parallel_portio_hw_list[] = {
485     { 0, 8, 1,
486       .read = parallel_ioport_read_hw,
487       .write = parallel_ioport_write_hw },
488     { 4, 1, 2,
489       .read = parallel_ioport_eppdata_read_hw2,
490       .write = parallel_ioport_eppdata_write_hw2 },
491     { 4, 1, 4,
492       .read = parallel_ioport_eppdata_read_hw4,
493       .write = parallel_ioport_eppdata_write_hw4 },
494     { 0x400, 8, 1,
495       .read = parallel_ioport_ecp_read,
496       .write = parallel_ioport_ecp_write },
497     PORTIO_END_OF_LIST(),
498 };
499 
500 static const MemoryRegionPortio isa_parallel_portio_sw_list[] = {
501     { 0, 8, 1,
502       .read = parallel_ioport_read_sw,
503       .write = parallel_ioport_write_sw },
504     PORTIO_END_OF_LIST(),
505 };
506 
507 
508 static const VMStateDescription vmstate_parallel_isa = {
509     .name = "parallel_isa",
510     .version_id = 1,
511     .minimum_version_id = 1,
512     .fields      = (VMStateField[]) {
513         VMSTATE_UINT8(state.dataw, ISAParallelState),
514         VMSTATE_UINT8(state.datar, ISAParallelState),
515         VMSTATE_UINT8(state.status, ISAParallelState),
516         VMSTATE_UINT8(state.control, ISAParallelState),
517         VMSTATE_INT32(state.irq_pending, ISAParallelState),
518         VMSTATE_INT32(state.epp_timeout, ISAParallelState),
519         VMSTATE_END_OF_LIST()
520     }
521 };
522 
523 static int parallel_can_receive(void *opaque)
524 {
525      return 1;
526 }
527 
528 static void parallel_isa_realizefn(DeviceState *dev, Error **errp)
529 {
530     static int index;
531     ISADevice *isadev = ISA_DEVICE(dev);
532     ISAParallelState *isa = ISA_PARALLEL(dev);
533     ParallelState *s = &isa->state;
534     int base;
535     uint8_t dummy;
536 
537     if (!qemu_chr_fe_backend_connected(&s->chr)) {
538         error_setg(errp, "Can't create parallel device, empty char device");
539         return;
540     }
541 
542     if (isa->index == -1) {
543         isa->index = index;
544     }
545     if (isa->index >= MAX_PARALLEL_PORTS) {
546         error_setg(errp, "Max. supported number of parallel ports is %d.",
547                    MAX_PARALLEL_PORTS);
548         return;
549     }
550     if (isa->iobase == -1) {
551         isa->iobase = isa_parallel_io[isa->index];
552     }
553     index++;
554 
555     base = isa->iobase;
556     s->irq = isa_get_irq(isadev, isa->isairq);
557     qemu_register_reset(parallel_reset, s);
558 
559     qemu_chr_fe_set_handlers(&s->chr, parallel_can_receive, NULL,
560                              NULL, NULL, s, NULL, true);
561     if (qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_STATUS, &dummy) == 0) {
562         s->hw_driver = 1;
563         s->status = dummy;
564     }
565 
566     isa_register_portio_list(isadev, &s->portio_list, base,
567                              (s->hw_driver
568                               ? &isa_parallel_portio_hw_list[0]
569                               : &isa_parallel_portio_sw_list[0]),
570                              s, "parallel");
571 }
572 
573 static void parallel_isa_build_aml(AcpiDevAmlIf *adev, Aml *scope)
574 {
575     ISAParallelState *isa = ISA_PARALLEL(adev);
576     Aml *dev;
577     Aml *crs;
578 
579     crs = aml_resource_template();
580     aml_append(crs, aml_io(AML_DECODE16, isa->iobase, isa->iobase, 0x08, 0x08));
581     aml_append(crs, aml_irq_no_flags(isa->isairq));
582 
583     dev = aml_device("LPT%d", isa->index + 1);
584     aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0400")));
585     aml_append(dev, aml_name_decl("_UID", aml_int(isa->index + 1)));
586     aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
587     aml_append(dev, aml_name_decl("_CRS", crs));
588 
589     aml_append(scope, dev);
590 }
591 
592 /* Memory mapped interface */
593 static uint64_t parallel_mm_readfn(void *opaque, hwaddr addr, unsigned size)
594 {
595     ParallelState *s = opaque;
596 
597     return parallel_ioport_read_sw(s, addr >> s->it_shift) &
598         MAKE_64BIT_MASK(0, size * 8);
599 }
600 
601 static void parallel_mm_writefn(void *opaque, hwaddr addr,
602                                 uint64_t value, unsigned size)
603 {
604     ParallelState *s = opaque;
605 
606     parallel_ioport_write_sw(s, addr >> s->it_shift,
607                              value & MAKE_64BIT_MASK(0, size * 8));
608 }
609 
610 static const MemoryRegionOps parallel_mm_ops = {
611     .read = parallel_mm_readfn,
612     .write = parallel_mm_writefn,
613     .valid.min_access_size = 1,
614     .valid.max_access_size = 4,
615     .endianness = DEVICE_NATIVE_ENDIAN,
616 };
617 
618 /* If fd is zero, it means that the parallel device uses the console */
619 bool parallel_mm_init(MemoryRegion *address_space,
620                       hwaddr base, int it_shift, qemu_irq irq,
621                       Chardev *chr)
622 {
623     ParallelState *s;
624 
625     s = g_new0(ParallelState, 1);
626     s->irq = irq;
627     qemu_chr_fe_init(&s->chr, chr, &error_abort);
628     s->it_shift = it_shift;
629     qemu_register_reset(parallel_reset, s);
630 
631     memory_region_init_io(&s->iomem, NULL, &parallel_mm_ops, s,
632                           "parallel", 8 << it_shift);
633     memory_region_add_subregion(address_space, base, &s->iomem);
634     return true;
635 }
636 
637 static Property parallel_isa_properties[] = {
638     DEFINE_PROP_UINT32("index", ISAParallelState, index,   -1),
639     DEFINE_PROP_UINT32("iobase", ISAParallelState, iobase,  -1),
640     DEFINE_PROP_UINT32("irq",   ISAParallelState, isairq,  7),
641     DEFINE_PROP_CHR("chardev",  ISAParallelState, state.chr),
642     DEFINE_PROP_END_OF_LIST(),
643 };
644 
645 static void parallel_isa_class_initfn(ObjectClass *klass, void *data)
646 {
647     DeviceClass *dc = DEVICE_CLASS(klass);
648     AcpiDevAmlIfClass *adevc = ACPI_DEV_AML_IF_CLASS(klass);
649 
650     dc->realize = parallel_isa_realizefn;
651     dc->vmsd = &vmstate_parallel_isa;
652     adevc->build_dev_aml = parallel_isa_build_aml;
653     device_class_set_props(dc, parallel_isa_properties);
654     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
655 }
656 
657 static const TypeInfo parallel_isa_info = {
658     .name          = TYPE_ISA_PARALLEL,
659     .parent        = TYPE_ISA_DEVICE,
660     .instance_size = sizeof(ISAParallelState),
661     .class_init    = parallel_isa_class_initfn,
662     .interfaces = (InterfaceInfo[]) {
663         { TYPE_ACPI_DEV_AML_IF },
664         { },
665     },
666 };
667 
668 static void parallel_register_types(void)
669 {
670     type_register_static(&parallel_isa_info);
671 }
672 
673 type_init(parallel_register_types)
674