xref: /qemu/hw/char/parallel.c (revision 8110fa1d)
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/aml-build.h"
32 #include "hw/irq.h"
33 #include "hw/isa/isa.h"
34 #include "hw/qdev-properties.h"
35 #include "migration/vmstate.h"
36 #include "hw/char/parallel.h"
37 #include "sysemu/reset.h"
38 #include "sysemu/sysemu.h"
39 #include "trace.h"
40 #include "qom/object.h"
41 
42 //#define DEBUG_PARALLEL
43 
44 #ifdef DEBUG_PARALLEL
45 #define pdebug(fmt, ...) printf("pp: " fmt, ## __VA_ARGS__)
46 #else
47 #define pdebug(fmt, ...) ((void)0)
48 #endif
49 
50 #define PARA_REG_DATA 0
51 #define PARA_REG_STS 1
52 #define PARA_REG_CTR 2
53 #define PARA_REG_EPP_ADDR 3
54 #define PARA_REG_EPP_DATA 4
55 
56 /*
57  * These are the definitions for the Printer Status Register
58  */
59 #define PARA_STS_BUSY	0x80	/* Busy complement */
60 #define PARA_STS_ACK	0x40	/* Acknowledge */
61 #define PARA_STS_PAPER	0x20	/* Out of paper */
62 #define PARA_STS_ONLINE	0x10	/* Online */
63 #define PARA_STS_ERROR	0x08	/* Error complement */
64 #define PARA_STS_TMOUT	0x01	/* EPP timeout */
65 
66 /*
67  * These are the definitions for the Printer Control Register
68  */
69 #define PARA_CTR_DIR	0x20	/* Direction (1=read, 0=write) */
70 #define PARA_CTR_INTEN	0x10	/* IRQ Enable */
71 #define PARA_CTR_SELECT	0x08	/* Select In complement */
72 #define PARA_CTR_INIT	0x04	/* Initialize Printer complement */
73 #define PARA_CTR_AUTOLF	0x02	/* Auto linefeed complement */
74 #define PARA_CTR_STROBE	0x01	/* Strobe complement */
75 
76 #define PARA_CTR_SIGNAL (PARA_CTR_SELECT|PARA_CTR_INIT|PARA_CTR_AUTOLF|PARA_CTR_STROBE)
77 
78 typedef struct ParallelState {
79     MemoryRegion iomem;
80     uint8_t dataw;
81     uint8_t datar;
82     uint8_t status;
83     uint8_t control;
84     qemu_irq irq;
85     int irq_pending;
86     CharBackend chr;
87     int hw_driver;
88     int epp_timeout;
89     uint32_t last_read_offset; /* For debugging */
90     /* Memory-mapped interface */
91     int it_shift;
92     PortioList portio_list;
93 } ParallelState;
94 
95 #define TYPE_ISA_PARALLEL "isa-parallel"
96 typedef struct ISAParallelState ISAParallelState;
97 DECLARE_INSTANCE_CHECKER(ISAParallelState, ISA_PARALLEL,
98                          TYPE_ISA_PARALLEL)
99 
100 struct ISAParallelState {
101     ISADevice parent_obj;
102 
103     uint32_t index;
104     uint32_t iobase;
105     uint32_t isairq;
106     ParallelState state;
107 };
108 
109 static void parallel_update_irq(ParallelState *s)
110 {
111     if (s->irq_pending)
112         qemu_irq_raise(s->irq);
113     else
114         qemu_irq_lower(s->irq);
115 }
116 
117 static void
118 parallel_ioport_write_sw(void *opaque, uint32_t addr, uint32_t val)
119 {
120     ParallelState *s = opaque;
121 
122     addr &= 7;
123     trace_parallel_ioport_write("SW", addr, val);
124     switch(addr) {
125     case PARA_REG_DATA:
126         s->dataw = val;
127         parallel_update_irq(s);
128         break;
129     case PARA_REG_CTR:
130         val |= 0xc0;
131         if ((val & PARA_CTR_INIT) == 0 ) {
132             s->status = PARA_STS_BUSY;
133             s->status |= PARA_STS_ACK;
134             s->status |= PARA_STS_ONLINE;
135             s->status |= PARA_STS_ERROR;
136         }
137         else if (val & PARA_CTR_SELECT) {
138             if (val & PARA_CTR_STROBE) {
139                 s->status &= ~PARA_STS_BUSY;
140                 if ((s->control & PARA_CTR_STROBE) == 0)
141                     /* XXX this blocks entire thread. Rewrite to use
142                      * qemu_chr_fe_write and background I/O callbacks */
143                     qemu_chr_fe_write_all(&s->chr, &s->dataw, 1);
144             } else {
145                 if (s->control & PARA_CTR_INTEN) {
146                     s->irq_pending = 1;
147                 }
148             }
149         }
150         parallel_update_irq(s);
151         s->control = val;
152         break;
153     }
154 }
155 
156 static void parallel_ioport_write_hw(void *opaque, uint32_t addr, uint32_t val)
157 {
158     ParallelState *s = opaque;
159     uint8_t parm = val;
160     int dir;
161 
162     /* Sometimes programs do several writes for timing purposes on old
163        HW. Take care not to waste time on writes that do nothing. */
164 
165     s->last_read_offset = ~0U;
166 
167     addr &= 7;
168     trace_parallel_ioport_write("HW", addr, val);
169     switch(addr) {
170     case PARA_REG_DATA:
171         if (s->dataw == val)
172             return;
173         pdebug("wd%02x\n", val);
174         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_WRITE_DATA, &parm);
175         s->dataw = val;
176         break;
177     case PARA_REG_STS:
178         pdebug("ws%02x\n", val);
179         if (val & PARA_STS_TMOUT)
180             s->epp_timeout = 0;
181         break;
182     case PARA_REG_CTR:
183         val |= 0xc0;
184         if (s->control == val)
185             return;
186         pdebug("wc%02x\n", val);
187 
188         if ((val & PARA_CTR_DIR) != (s->control & PARA_CTR_DIR)) {
189             if (val & PARA_CTR_DIR) {
190                 dir = 1;
191             } else {
192                 dir = 0;
193             }
194             qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_DATA_DIR, &dir);
195             parm &= ~PARA_CTR_DIR;
196         }
197 
198         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_WRITE_CONTROL, &parm);
199         s->control = val;
200         break;
201     case PARA_REG_EPP_ADDR:
202         if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT)
203             /* Controls not correct for EPP address cycle, so do nothing */
204             pdebug("wa%02x s\n", val);
205         else {
206             struct ParallelIOArg ioarg = { .buffer = &parm, .count = 1 };
207             if (qemu_chr_fe_ioctl(&s->chr,
208                                   CHR_IOCTL_PP_EPP_WRITE_ADDR, &ioarg)) {
209                 s->epp_timeout = 1;
210                 pdebug("wa%02x t\n", val);
211             }
212             else
213                 pdebug("wa%02x\n", val);
214         }
215         break;
216     case PARA_REG_EPP_DATA:
217         if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT)
218             /* Controls not correct for EPP data cycle, so do nothing */
219             pdebug("we%02x s\n", val);
220         else {
221             struct ParallelIOArg ioarg = { .buffer = &parm, .count = 1 };
222             if (qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg)) {
223                 s->epp_timeout = 1;
224                 pdebug("we%02x t\n", val);
225             }
226             else
227                 pdebug("we%02x\n", val);
228         }
229         break;
230     }
231 }
232 
233 static void
234 parallel_ioport_eppdata_write_hw2(void *opaque, uint32_t addr, uint32_t val)
235 {
236     ParallelState *s = opaque;
237     uint16_t eppdata = cpu_to_le16(val);
238     int err;
239     struct ParallelIOArg ioarg = {
240         .buffer = &eppdata, .count = sizeof(eppdata)
241     };
242 
243     trace_parallel_ioport_write("EPP", addr, val);
244     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT) {
245         /* Controls not correct for EPP data cycle, so do nothing */
246         pdebug("we%04x s\n", val);
247         return;
248     }
249     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg);
250     if (err) {
251         s->epp_timeout = 1;
252         pdebug("we%04x t\n", val);
253     }
254     else
255         pdebug("we%04x\n", val);
256 }
257 
258 static void
259 parallel_ioport_eppdata_write_hw4(void *opaque, uint32_t addr, uint32_t val)
260 {
261     ParallelState *s = opaque;
262     uint32_t eppdata = cpu_to_le32(val);
263     int err;
264     struct ParallelIOArg ioarg = {
265         .buffer = &eppdata, .count = sizeof(eppdata)
266     };
267 
268     trace_parallel_ioport_write("EPP", addr, val);
269     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != PARA_CTR_INIT) {
270         /* Controls not correct for EPP data cycle, so do nothing */
271         pdebug("we%08x s\n", val);
272         return;
273     }
274     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_WRITE, &ioarg);
275     if (err) {
276         s->epp_timeout = 1;
277         pdebug("we%08x t\n", val);
278     }
279     else
280         pdebug("we%08x\n", val);
281 }
282 
283 static uint32_t parallel_ioport_read_sw(void *opaque, uint32_t addr)
284 {
285     ParallelState *s = opaque;
286     uint32_t ret = 0xff;
287 
288     addr &= 7;
289     switch(addr) {
290     case PARA_REG_DATA:
291         if (s->control & PARA_CTR_DIR)
292             ret = s->datar;
293         else
294             ret = s->dataw;
295         break;
296     case PARA_REG_STS:
297         ret = s->status;
298         s->irq_pending = 0;
299         if ((s->status & PARA_STS_BUSY) == 0 && (s->control & PARA_CTR_STROBE) == 0) {
300             /* XXX Fixme: wait 5 microseconds */
301             if (s->status & PARA_STS_ACK)
302                 s->status &= ~PARA_STS_ACK;
303             else {
304                 /* XXX Fixme: wait 5 microseconds */
305                 s->status |= PARA_STS_ACK;
306                 s->status |= PARA_STS_BUSY;
307             }
308         }
309         parallel_update_irq(s);
310         break;
311     case PARA_REG_CTR:
312         ret = s->control;
313         break;
314     }
315     trace_parallel_ioport_read("SW", addr, ret);
316     return ret;
317 }
318 
319 static uint32_t parallel_ioport_read_hw(void *opaque, uint32_t addr)
320 {
321     ParallelState *s = opaque;
322     uint8_t ret = 0xff;
323     addr &= 7;
324     switch(addr) {
325     case PARA_REG_DATA:
326         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_DATA, &ret);
327         if (s->last_read_offset != addr || s->datar != ret)
328             pdebug("rd%02x\n", ret);
329         s->datar = ret;
330         break;
331     case PARA_REG_STS:
332         qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_STATUS, &ret);
333         ret &= ~PARA_STS_TMOUT;
334         if (s->epp_timeout)
335             ret |= PARA_STS_TMOUT;
336         if (s->last_read_offset != addr || s->status != ret)
337             pdebug("rs%02x\n", ret);
338         s->status = ret;
339         break;
340     case PARA_REG_CTR:
341         /* s->control has some bits fixed to 1. It is zero only when
342            it has not been yet written to.  */
343         if (s->control == 0) {
344             qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_CONTROL, &ret);
345             if (s->last_read_offset != addr)
346                 pdebug("rc%02x\n", ret);
347             s->control = ret;
348         }
349         else {
350             ret = s->control;
351             if (s->last_read_offset != addr)
352                 pdebug("rc%02x\n", ret);
353         }
354         break;
355     case PARA_REG_EPP_ADDR:
356         if ((s->control & (PARA_CTR_DIR | PARA_CTR_SIGNAL)) !=
357             (PARA_CTR_DIR | PARA_CTR_INIT))
358             /* Controls not correct for EPP addr cycle, so do nothing */
359             pdebug("ra%02x s\n", ret);
360         else {
361             struct ParallelIOArg ioarg = { .buffer = &ret, .count = 1 };
362             if (qemu_chr_fe_ioctl(&s->chr,
363                                   CHR_IOCTL_PP_EPP_READ_ADDR, &ioarg)) {
364                 s->epp_timeout = 1;
365                 pdebug("ra%02x t\n", ret);
366             }
367             else
368                 pdebug("ra%02x\n", ret);
369         }
370         break;
371     case PARA_REG_EPP_DATA:
372         if ((s->control & (PARA_CTR_DIR | PARA_CTR_SIGNAL)) !=
373             (PARA_CTR_DIR | PARA_CTR_INIT))
374             /* Controls not correct for EPP data cycle, so do nothing */
375             pdebug("re%02x s\n", ret);
376         else {
377             struct ParallelIOArg ioarg = { .buffer = &ret, .count = 1 };
378             if (qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg)) {
379                 s->epp_timeout = 1;
380                 pdebug("re%02x t\n", ret);
381             }
382             else
383                 pdebug("re%02x\n", ret);
384         }
385         break;
386     }
387     trace_parallel_ioport_read("HW", addr, ret);
388     s->last_read_offset = addr;
389     return ret;
390 }
391 
392 static uint32_t
393 parallel_ioport_eppdata_read_hw2(void *opaque, uint32_t addr)
394 {
395     ParallelState *s = opaque;
396     uint32_t ret;
397     uint16_t eppdata = ~0;
398     int err;
399     struct ParallelIOArg ioarg = {
400         .buffer = &eppdata, .count = sizeof(eppdata)
401     };
402     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT)) {
403         /* Controls not correct for EPP data cycle, so do nothing */
404         pdebug("re%04x s\n", eppdata);
405         return eppdata;
406     }
407     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg);
408     ret = le16_to_cpu(eppdata);
409 
410     if (err) {
411         s->epp_timeout = 1;
412         pdebug("re%04x t\n", ret);
413     }
414     else
415         pdebug("re%04x\n", ret);
416     trace_parallel_ioport_read("EPP", addr, ret);
417     return ret;
418 }
419 
420 static uint32_t
421 parallel_ioport_eppdata_read_hw4(void *opaque, uint32_t addr)
422 {
423     ParallelState *s = opaque;
424     uint32_t ret;
425     uint32_t eppdata = ~0U;
426     int err;
427     struct ParallelIOArg ioarg = {
428         .buffer = &eppdata, .count = sizeof(eppdata)
429     };
430     if ((s->control & (PARA_CTR_DIR|PARA_CTR_SIGNAL)) != (PARA_CTR_DIR|PARA_CTR_INIT)) {
431         /* Controls not correct for EPP data cycle, so do nothing */
432         pdebug("re%08x s\n", eppdata);
433         return eppdata;
434     }
435     err = qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_EPP_READ, &ioarg);
436     ret = le32_to_cpu(eppdata);
437 
438     if (err) {
439         s->epp_timeout = 1;
440         pdebug("re%08x t\n", ret);
441     }
442     else
443         pdebug("re%08x\n", ret);
444     trace_parallel_ioport_read("EPP", addr, ret);
445     return ret;
446 }
447 
448 static void parallel_ioport_ecp_write(void *opaque, uint32_t addr, uint32_t val)
449 {
450     trace_parallel_ioport_write("ECP", addr & 7, val);
451     pdebug("wecp%d=%02x\n", addr & 7, val);
452 }
453 
454 static uint32_t parallel_ioport_ecp_read(void *opaque, uint32_t addr)
455 {
456     uint8_t ret = 0xff;
457 
458     trace_parallel_ioport_read("ECP", addr & 7, ret);
459     pdebug("recp%d:%02x\n", addr & 7, ret);
460     return ret;
461 }
462 
463 static void parallel_reset(void *opaque)
464 {
465     ParallelState *s = opaque;
466 
467     s->datar = ~0;
468     s->dataw = ~0;
469     s->status = PARA_STS_BUSY;
470     s->status |= PARA_STS_ACK;
471     s->status |= PARA_STS_ONLINE;
472     s->status |= PARA_STS_ERROR;
473     s->status |= PARA_STS_TMOUT;
474     s->control = PARA_CTR_SELECT;
475     s->control |= PARA_CTR_INIT;
476     s->control |= 0xc0;
477     s->irq_pending = 0;
478     s->hw_driver = 0;
479     s->epp_timeout = 0;
480     s->last_read_offset = ~0U;
481 }
482 
483 static const int isa_parallel_io[MAX_PARALLEL_PORTS] = { 0x378, 0x278, 0x3bc };
484 
485 static const MemoryRegionPortio isa_parallel_portio_hw_list[] = {
486     { 0, 8, 1,
487       .read = parallel_ioport_read_hw,
488       .write = parallel_ioport_write_hw },
489     { 4, 1, 2,
490       .read = parallel_ioport_eppdata_read_hw2,
491       .write = parallel_ioport_eppdata_write_hw2 },
492     { 4, 1, 4,
493       .read = parallel_ioport_eppdata_read_hw4,
494       .write = parallel_ioport_eppdata_write_hw4 },
495     { 0x400, 8, 1,
496       .read = parallel_ioport_ecp_read,
497       .write = parallel_ioport_ecp_write },
498     PORTIO_END_OF_LIST(),
499 };
500 
501 static const MemoryRegionPortio isa_parallel_portio_sw_list[] = {
502     { 0, 8, 1,
503       .read = parallel_ioport_read_sw,
504       .write = parallel_ioport_write_sw },
505     PORTIO_END_OF_LIST(),
506 };
507 
508 
509 static const VMStateDescription vmstate_parallel_isa = {
510     .name = "parallel_isa",
511     .version_id = 1,
512     .minimum_version_id = 1,
513     .fields      = (VMStateField[]) {
514         VMSTATE_UINT8(state.dataw, ISAParallelState),
515         VMSTATE_UINT8(state.datar, ISAParallelState),
516         VMSTATE_UINT8(state.status, ISAParallelState),
517         VMSTATE_UINT8(state.control, ISAParallelState),
518         VMSTATE_INT32(state.irq_pending, ISAParallelState),
519         VMSTATE_INT32(state.epp_timeout, ISAParallelState),
520         VMSTATE_END_OF_LIST()
521     }
522 };
523 
524 static int parallel_can_receive(void *opaque)
525 {
526      return 1;
527 }
528 
529 static void parallel_isa_realizefn(DeviceState *dev, Error **errp)
530 {
531     static int index;
532     ISADevice *isadev = ISA_DEVICE(dev);
533     ISAParallelState *isa = ISA_PARALLEL(dev);
534     ParallelState *s = &isa->state;
535     int base;
536     uint8_t dummy;
537 
538     if (!qemu_chr_fe_backend_connected(&s->chr)) {
539         error_setg(errp, "Can't create parallel device, empty char device");
540         return;
541     }
542 
543     if (isa->index == -1) {
544         isa->index = index;
545     }
546     if (isa->index >= MAX_PARALLEL_PORTS) {
547         error_setg(errp, "Max. supported number of parallel ports is %d.",
548                    MAX_PARALLEL_PORTS);
549         return;
550     }
551     if (isa->iobase == -1) {
552         isa->iobase = isa_parallel_io[isa->index];
553     }
554     index++;
555 
556     base = isa->iobase;
557     isa_init_irq(isadev, &s->irq, isa->isairq);
558     qemu_register_reset(parallel_reset, s);
559 
560     qemu_chr_fe_set_handlers(&s->chr, parallel_can_receive, NULL,
561                              NULL, NULL, s, NULL, true);
562     if (qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_PP_READ_STATUS, &dummy) == 0) {
563         s->hw_driver = 1;
564         s->status = dummy;
565     }
566 
567     isa_register_portio_list(isadev, &s->portio_list, base,
568                              (s->hw_driver
569                               ? &isa_parallel_portio_hw_list[0]
570                               : &isa_parallel_portio_sw_list[0]),
571                              s, "parallel");
572 }
573 
574 static void parallel_isa_build_aml(ISADevice *isadev, Aml *scope)
575 {
576     ISAParallelState *isa = ISA_PARALLEL(isadev);
577     Aml *dev;
578     Aml *crs;
579 
580     crs = aml_resource_template();
581     aml_append(crs, aml_io(AML_DECODE16, isa->iobase, isa->iobase, 0x08, 0x08));
582     aml_append(crs, aml_irq_no_flags(isa->isairq));
583 
584     dev = aml_device("LPT%d", isa->index + 1);
585     aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0400")));
586     aml_append(dev, aml_name_decl("_UID", aml_int(isa->index + 1)));
587     aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
588     aml_append(dev, aml_name_decl("_CRS", crs));
589 
590     aml_append(scope, dev);
591 }
592 
593 /* Memory mapped interface */
594 static uint64_t parallel_mm_readfn(void *opaque, hwaddr addr, unsigned size)
595 {
596     ParallelState *s = opaque;
597 
598     return parallel_ioport_read_sw(s, addr >> s->it_shift) &
599         MAKE_64BIT_MASK(0, size * 8);
600 }
601 
602 static void parallel_mm_writefn(void *opaque, hwaddr addr,
603                                 uint64_t value, unsigned size)
604 {
605     ParallelState *s = opaque;
606 
607     parallel_ioport_write_sw(s, addr >> s->it_shift,
608                              value & MAKE_64BIT_MASK(0, size * 8));
609 }
610 
611 static const MemoryRegionOps parallel_mm_ops = {
612     .read = parallel_mm_readfn,
613     .write = parallel_mm_writefn,
614     .valid.min_access_size = 1,
615     .valid.max_access_size = 4,
616     .endianness = DEVICE_NATIVE_ENDIAN,
617 };
618 
619 /* If fd is zero, it means that the parallel device uses the console */
620 bool parallel_mm_init(MemoryRegion *address_space,
621                       hwaddr base, int it_shift, qemu_irq irq,
622                       Chardev *chr)
623 {
624     ParallelState *s;
625 
626     s = g_malloc0(sizeof(ParallelState));
627     s->irq = irq;
628     qemu_chr_fe_init(&s->chr, chr, &error_abort);
629     s->it_shift = it_shift;
630     qemu_register_reset(parallel_reset, s);
631 
632     memory_region_init_io(&s->iomem, NULL, &parallel_mm_ops, s,
633                           "parallel", 8 << it_shift);
634     memory_region_add_subregion(address_space, base, &s->iomem);
635     return true;
636 }
637 
638 static Property parallel_isa_properties[] = {
639     DEFINE_PROP_UINT32("index", ISAParallelState, index,   -1),
640     DEFINE_PROP_UINT32("iobase", ISAParallelState, iobase,  -1),
641     DEFINE_PROP_UINT32("irq",   ISAParallelState, isairq,  7),
642     DEFINE_PROP_CHR("chardev",  ISAParallelState, state.chr),
643     DEFINE_PROP_END_OF_LIST(),
644 };
645 
646 static void parallel_isa_class_initfn(ObjectClass *klass, void *data)
647 {
648     DeviceClass *dc = DEVICE_CLASS(klass);
649     ISADeviceClass *isa = ISA_DEVICE_CLASS(klass);
650 
651     dc->realize = parallel_isa_realizefn;
652     dc->vmsd = &vmstate_parallel_isa;
653     isa->build_aml = parallel_isa_build_aml;
654     device_class_set_props(dc, parallel_isa_properties);
655     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
656 }
657 
658 static const TypeInfo parallel_isa_info = {
659     .name          = TYPE_ISA_PARALLEL,
660     .parent        = TYPE_ISA_DEVICE,
661     .instance_size = sizeof(ISAParallelState),
662     .class_init    = parallel_isa_class_initfn,
663 };
664 
665 static void parallel_register_types(void)
666 {
667     type_register_static(&parallel_isa_info);
668 }
669 
670 type_init(parallel_register_types)
671