xref: /openbmc/qemu/hw/usb/dev-serial.c (revision 4a09d0bb)
1 /*
2  * FTDI FT232BM Device emulation
3  *
4  * Copyright (c) 2006 CodeSourcery.
5  * Copyright (c) 2008 Samuel Thibault <samuel.thibault@ens-lyon.org>
6  * Written by Paul Brook, reused for FTDI by Samuel Thibault
7  *
8  * This code is licensed under the LGPL.
9  */
10 
11 #include "qemu/osdep.h"
12 #include "qapi/error.h"
13 #include "qemu-common.h"
14 #include "qemu/cutils.h"
15 #include "qemu/error-report.h"
16 #include "hw/usb.h"
17 #include "hw/usb/desc.h"
18 #include "sysemu/char.h"
19 
20 //#define DEBUG_Serial
21 
22 #ifdef DEBUG_Serial
23 #define DPRINTF(fmt, ...) \
24 do { printf("usb-serial: " fmt , ## __VA_ARGS__); } while (0)
25 #else
26 #define DPRINTF(fmt, ...) do {} while(0)
27 #endif
28 
29 #define RECV_BUF 384
30 
31 /* Commands */
32 #define FTDI_RESET		0
33 #define FTDI_SET_MDM_CTRL	1
34 #define FTDI_SET_FLOW_CTRL	2
35 #define FTDI_SET_BAUD		3
36 #define FTDI_SET_DATA		4
37 #define FTDI_GET_MDM_ST		5
38 #define FTDI_SET_EVENT_CHR	6
39 #define FTDI_SET_ERROR_CHR	7
40 #define FTDI_SET_LATENCY	9
41 #define FTDI_GET_LATENCY	10
42 
43 #define DeviceOutVendor	((USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)
44 #define DeviceInVendor	((USB_DIR_IN |USB_TYPE_VENDOR|USB_RECIP_DEVICE)<<8)
45 
46 /* RESET */
47 
48 #define FTDI_RESET_SIO	0
49 #define FTDI_RESET_RX	1
50 #define FTDI_RESET_TX	2
51 
52 /* SET_MDM_CTRL */
53 
54 #define FTDI_DTR	1
55 #define FTDI_SET_DTR	(FTDI_DTR << 8)
56 #define FTDI_RTS	2
57 #define FTDI_SET_RTS	(FTDI_RTS << 8)
58 
59 /* SET_FLOW_CTRL */
60 
61 #define FTDI_RTS_CTS_HS		1
62 #define FTDI_DTR_DSR_HS		2
63 #define FTDI_XON_XOFF_HS	4
64 
65 /* SET_DATA */
66 
67 #define FTDI_PARITY	(0x7 << 8)
68 #define FTDI_ODD	(0x1 << 8)
69 #define FTDI_EVEN	(0x2 << 8)
70 #define FTDI_MARK	(0x3 << 8)
71 #define FTDI_SPACE	(0x4 << 8)
72 
73 #define FTDI_STOP	(0x3 << 11)
74 #define FTDI_STOP1	(0x0 << 11)
75 #define FTDI_STOP15	(0x1 << 11)
76 #define FTDI_STOP2	(0x2 << 11)
77 
78 /* GET_MDM_ST */
79 /* TODO: should be sent every 40ms */
80 #define FTDI_CTS  (1<<4)        // CTS line status
81 #define FTDI_DSR  (1<<5)        // DSR line status
82 #define FTDI_RI   (1<<6)        // RI line status
83 #define FTDI_RLSD (1<<7)        // Receive Line Signal Detect
84 
85 /* Status */
86 
87 #define FTDI_DR   (1<<0)        // Data Ready
88 #define FTDI_OE   (1<<1)        // Overrun Err
89 #define FTDI_PE   (1<<2)        // Parity Err
90 #define FTDI_FE   (1<<3)        // Framing Err
91 #define FTDI_BI   (1<<4)        // Break Interrupt
92 #define FTDI_THRE (1<<5)        // Transmitter Holding Register
93 #define FTDI_TEMT (1<<6)        // Transmitter Empty
94 #define FTDI_FIFO (1<<7)        // Error in FIFO
95 
96 typedef struct {
97     USBDevice dev;
98     uint8_t recv_buf[RECV_BUF];
99     uint16_t recv_ptr;
100     uint16_t recv_used;
101     uint8_t event_chr;
102     uint8_t error_chr;
103     uint8_t event_trigger;
104     QEMUSerialSetParams params;
105     int latency;        /* ms */
106     CharBackend cs;
107 } USBSerialState;
108 
109 #define TYPE_USB_SERIAL "usb-serial-dev"
110 #define USB_SERIAL_DEV(obj) OBJECT_CHECK(USBSerialState, (obj), TYPE_USB_SERIAL)
111 
112 enum {
113     STR_MANUFACTURER = 1,
114     STR_PRODUCT_SERIAL,
115     STR_PRODUCT_BRAILLE,
116     STR_SERIALNUMBER,
117 };
118 
119 static const USBDescStrings desc_strings = {
120     [STR_MANUFACTURER]    = "QEMU",
121     [STR_PRODUCT_SERIAL]  = "QEMU USB SERIAL",
122     [STR_PRODUCT_BRAILLE] = "QEMU USB BAUM BRAILLE",
123     [STR_SERIALNUMBER]    = "1",
124 };
125 
126 static const USBDescIface desc_iface0 = {
127     .bInterfaceNumber              = 0,
128     .bNumEndpoints                 = 2,
129     .bInterfaceClass               = 0xff,
130     .bInterfaceSubClass            = 0xff,
131     .bInterfaceProtocol            = 0xff,
132     .eps = (USBDescEndpoint[]) {
133         {
134             .bEndpointAddress      = USB_DIR_IN | 0x01,
135             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
136             .wMaxPacketSize        = 64,
137         },{
138             .bEndpointAddress      = USB_DIR_OUT | 0x02,
139             .bmAttributes          = USB_ENDPOINT_XFER_BULK,
140             .wMaxPacketSize        = 64,
141         },
142     }
143 };
144 
145 static const USBDescDevice desc_device = {
146     .bcdUSB                        = 0x0200,
147     .bMaxPacketSize0               = 8,
148     .bNumConfigurations            = 1,
149     .confs = (USBDescConfig[]) {
150         {
151             .bNumInterfaces        = 1,
152             .bConfigurationValue   = 1,
153             .bmAttributes          = USB_CFG_ATT_ONE,
154             .bMaxPower             = 50,
155             .nif = 1,
156             .ifs = &desc_iface0,
157         },
158     },
159 };
160 
161 static const USBDesc desc_serial = {
162     .id = {
163         .idVendor          = 0x0403,
164         .idProduct         = 0x6001,
165         .bcdDevice         = 0x0400,
166         .iManufacturer     = STR_MANUFACTURER,
167         .iProduct          = STR_PRODUCT_SERIAL,
168         .iSerialNumber     = STR_SERIALNUMBER,
169     },
170     .full = &desc_device,
171     .str  = desc_strings,
172 };
173 
174 static const USBDesc desc_braille = {
175     .id = {
176         .idVendor          = 0x0403,
177         .idProduct         = 0xfe72,
178         .bcdDevice         = 0x0400,
179         .iManufacturer     = STR_MANUFACTURER,
180         .iProduct          = STR_PRODUCT_BRAILLE,
181         .iSerialNumber     = STR_SERIALNUMBER,
182     },
183     .full = &desc_device,
184     .str  = desc_strings,
185 };
186 
187 static void usb_serial_reset(USBSerialState *s)
188 {
189     /* TODO: Set flow control to none */
190     s->event_chr = 0x0d;
191     s->event_trigger = 0;
192     s->recv_ptr = 0;
193     s->recv_used = 0;
194     /* TODO: purge in char driver */
195 }
196 
197 static void usb_serial_handle_reset(USBDevice *dev)
198 {
199     USBSerialState *s = (USBSerialState *)dev;
200 
201     DPRINTF("Reset\n");
202 
203     usb_serial_reset(s);
204     /* TODO: Reset char device, send BREAK? */
205 }
206 
207 static uint8_t usb_get_modem_lines(USBSerialState *s)
208 {
209     int flags;
210     uint8_t ret;
211 
212     if (qemu_chr_fe_ioctl(&s->cs,
213                           CHR_IOCTL_SERIAL_GET_TIOCM, &flags) == -ENOTSUP) {
214         return FTDI_CTS|FTDI_DSR|FTDI_RLSD;
215     }
216 
217     ret = 0;
218     if (flags & CHR_TIOCM_CTS)
219         ret |= FTDI_CTS;
220     if (flags & CHR_TIOCM_DSR)
221         ret |= FTDI_DSR;
222     if (flags & CHR_TIOCM_RI)
223         ret |= FTDI_RI;
224     if (flags & CHR_TIOCM_CAR)
225         ret |= FTDI_RLSD;
226 
227     return ret;
228 }
229 
230 static void usb_serial_handle_control(USBDevice *dev, USBPacket *p,
231                int request, int value, int index, int length, uint8_t *data)
232 {
233     USBSerialState *s = (USBSerialState *)dev;
234     int ret;
235 
236     DPRINTF("got control %x, value %x\n",request, value);
237     ret = usb_desc_handle_control(dev, p, request, value, index, length, data);
238     if (ret >= 0) {
239         return;
240     }
241 
242     switch (request) {
243     case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
244         break;
245 
246         /* Class specific requests.  */
247     case DeviceOutVendor | FTDI_RESET:
248         switch (value) {
249         case FTDI_RESET_SIO:
250             usb_serial_reset(s);
251             break;
252         case FTDI_RESET_RX:
253             s->recv_ptr = 0;
254             s->recv_used = 0;
255             /* TODO: purge from char device */
256             break;
257         case FTDI_RESET_TX:
258             /* TODO: purge from char device */
259             break;
260         }
261         break;
262     case DeviceOutVendor | FTDI_SET_MDM_CTRL:
263     {
264         static int flags;
265         qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_GET_TIOCM, &flags);
266         if (value & FTDI_SET_RTS) {
267             if (value & FTDI_RTS)
268                 flags |= CHR_TIOCM_RTS;
269             else
270                 flags &= ~CHR_TIOCM_RTS;
271         }
272         if (value & FTDI_SET_DTR) {
273             if (value & FTDI_DTR)
274                 flags |= CHR_TIOCM_DTR;
275             else
276                 flags &= ~CHR_TIOCM_DTR;
277         }
278         qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_SET_TIOCM, &flags);
279         break;
280     }
281     case DeviceOutVendor | FTDI_SET_FLOW_CTRL:
282         /* TODO: ioctl */
283         break;
284     case DeviceOutVendor | FTDI_SET_BAUD: {
285         static const int subdivisors8[8] = { 0, 4, 2, 1, 3, 5, 6, 7 };
286         int subdivisor8 = subdivisors8[((value & 0xc000) >> 14)
287                                      | ((index & 1) << 2)];
288         int divisor = value & 0x3fff;
289 
290         /* chip special cases */
291         if (divisor == 1 && subdivisor8 == 0)
292             subdivisor8 = 4;
293         if (divisor == 0 && subdivisor8 == 0)
294             divisor = 1;
295 
296         s->params.speed = (48000000 / 2) / (8 * divisor + subdivisor8);
297         qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);
298         break;
299     }
300     case DeviceOutVendor | FTDI_SET_DATA:
301         switch (value & FTDI_PARITY) {
302             case 0:
303                 s->params.parity = 'N';
304                 break;
305             case FTDI_ODD:
306                 s->params.parity = 'O';
307                 break;
308             case FTDI_EVEN:
309                 s->params.parity = 'E';
310                 break;
311             default:
312                 DPRINTF("unsupported parity %d\n", value & FTDI_PARITY);
313                 goto fail;
314         }
315         switch (value & FTDI_STOP) {
316             case FTDI_STOP1:
317                 s->params.stop_bits = 1;
318                 break;
319             case FTDI_STOP2:
320                 s->params.stop_bits = 2;
321                 break;
322             default:
323                 DPRINTF("unsupported stop bits %d\n", value & FTDI_STOP);
324                 goto fail;
325         }
326         qemu_chr_fe_ioctl(&s->cs, CHR_IOCTL_SERIAL_SET_PARAMS, &s->params);
327         /* TODO: TX ON/OFF */
328         break;
329     case DeviceInVendor | FTDI_GET_MDM_ST:
330         data[0] = usb_get_modem_lines(s) | 1;
331         data[1] = 0;
332         p->actual_length = 2;
333         break;
334     case DeviceOutVendor | FTDI_SET_EVENT_CHR:
335         /* TODO: handle it */
336         s->event_chr = value;
337         break;
338     case DeviceOutVendor | FTDI_SET_ERROR_CHR:
339         /* TODO: handle it */
340         s->error_chr = value;
341         break;
342     case DeviceOutVendor | FTDI_SET_LATENCY:
343         s->latency = value;
344         break;
345     case DeviceInVendor | FTDI_GET_LATENCY:
346         data[0] = s->latency;
347         p->actual_length = 1;
348         break;
349     default:
350     fail:
351         DPRINTF("got unsupported/bogus control %x, value %x\n", request, value);
352         p->status = USB_RET_STALL;
353         break;
354     }
355 }
356 
357 static void usb_serial_handle_data(USBDevice *dev, USBPacket *p)
358 {
359     USBSerialState *s = (USBSerialState *)dev;
360     uint8_t devep = p->ep->nr;
361     struct iovec *iov;
362     uint8_t header[2];
363     int i, first_len, len;
364 
365     switch (p->pid) {
366     case USB_TOKEN_OUT:
367         if (devep != 2)
368             goto fail;
369         for (i = 0; i < p->iov.niov; i++) {
370             iov = p->iov.iov + i;
371             /* XXX this blocks entire thread. Rewrite to use
372              * qemu_chr_fe_write and background I/O callbacks */
373             qemu_chr_fe_write_all(&s->cs, iov->iov_base, iov->iov_len);
374         }
375         p->actual_length = p->iov.size;
376         break;
377 
378     case USB_TOKEN_IN:
379         if (devep != 1)
380             goto fail;
381         first_len = RECV_BUF - s->recv_ptr;
382         len = p->iov.size;
383         if (len <= 2) {
384             p->status = USB_RET_NAK;
385             break;
386         }
387         header[0] = usb_get_modem_lines(s) | 1;
388         /* We do not have the uart details */
389         /* handle serial break */
390         if (s->event_trigger && s->event_trigger & FTDI_BI) {
391             s->event_trigger &= ~FTDI_BI;
392             header[1] = FTDI_BI;
393             usb_packet_copy(p, header, 2);
394             break;
395         } else {
396             header[1] = 0;
397         }
398         len -= 2;
399         if (len > s->recv_used)
400             len = s->recv_used;
401         if (!len) {
402             p->status = USB_RET_NAK;
403             break;
404         }
405         if (first_len > len)
406             first_len = len;
407         usb_packet_copy(p, header, 2);
408         usb_packet_copy(p, s->recv_buf + s->recv_ptr, first_len);
409         if (len > first_len)
410             usb_packet_copy(p, s->recv_buf, len - first_len);
411         s->recv_used -= len;
412         s->recv_ptr = (s->recv_ptr + len) % RECV_BUF;
413         break;
414 
415     default:
416         DPRINTF("Bad token\n");
417     fail:
418         p->status = USB_RET_STALL;
419         break;
420     }
421 }
422 
423 static int usb_serial_can_read(void *opaque)
424 {
425     USBSerialState *s = opaque;
426 
427     if (!s->dev.attached) {
428         return 0;
429     }
430     return RECV_BUF - s->recv_used;
431 }
432 
433 static void usb_serial_read(void *opaque, const uint8_t *buf, int size)
434 {
435     USBSerialState *s = opaque;
436     int first_size, start;
437 
438     /* room in the buffer? */
439     if (size > (RECV_BUF - s->recv_used))
440         size = RECV_BUF - s->recv_used;
441 
442     start = s->recv_ptr + s->recv_used;
443     if (start < RECV_BUF) {
444         /* copy data to end of buffer */
445         first_size = RECV_BUF - start;
446         if (first_size > size)
447             first_size = size;
448 
449         memcpy(s->recv_buf + start, buf, first_size);
450 
451         /* wrap around to front if needed */
452         if (size > first_size)
453             memcpy(s->recv_buf, buf + first_size, size - first_size);
454     } else {
455         start -= RECV_BUF;
456         memcpy(s->recv_buf + start, buf, size);
457     }
458     s->recv_used += size;
459 }
460 
461 static void usb_serial_event(void *opaque, int event)
462 {
463     USBSerialState *s = opaque;
464 
465     switch (event) {
466         case CHR_EVENT_BREAK:
467             s->event_trigger |= FTDI_BI;
468             break;
469         case CHR_EVENT_OPENED:
470             if (!s->dev.attached) {
471                 usb_device_attach(&s->dev, &error_abort);
472             }
473             break;
474         case CHR_EVENT_CLOSED:
475             if (s->dev.attached) {
476                 usb_device_detach(&s->dev);
477             }
478             break;
479     }
480 }
481 
482 static void usb_serial_realize(USBDevice *dev, Error **errp)
483 {
484     USBSerialState *s = USB_SERIAL_DEV(dev);
485     Error *local_err = NULL;
486     Chardev *chr = qemu_chr_fe_get_driver(&s->cs);
487 
488     usb_desc_create_serial(dev);
489     usb_desc_init(dev);
490     dev->auto_attach = 0;
491 
492     if (!chr) {
493         error_setg(errp, "Property chardev is required");
494         return;
495     }
496 
497     usb_check_attach(dev, &local_err);
498     if (local_err) {
499         error_propagate(errp, local_err);
500         return;
501     }
502 
503     qemu_chr_fe_set_handlers(&s->cs, usb_serial_can_read, usb_serial_read,
504                              usb_serial_event, s, NULL, true);
505     usb_serial_handle_reset(dev);
506 
507     if (chr->be_open && !dev->attached) {
508         usb_device_attach(dev, &error_abort);
509     }
510 }
511 
512 static USBDevice *usb_serial_init(USBBus *bus, const char *filename)
513 {
514     USBDevice *dev;
515     Chardev *cdrv;
516     uint32_t vendorid = 0, productid = 0;
517     char label[32];
518     static int index;
519 
520     while (*filename && *filename != ':') {
521         const char *p;
522         char *e;
523         if (strstart(filename, "vendorid=", &p)) {
524             vendorid = strtol(p, &e, 16);
525             if (e == p || (*e && *e != ',' && *e != ':')) {
526                 error_report("bogus vendor ID %s", p);
527                 return NULL;
528             }
529             filename = e;
530         } else if (strstart(filename, "productid=", &p)) {
531             productid = strtol(p, &e, 16);
532             if (e == p || (*e && *e != ',' && *e != ':')) {
533                 error_report("bogus product ID %s", p);
534                 return NULL;
535             }
536             filename = e;
537         } else {
538             error_report("unrecognized serial USB option %s", filename);
539             return NULL;
540         }
541         while(*filename == ',')
542             filename++;
543     }
544     if (!*filename) {
545         error_report("character device specification needed");
546         return NULL;
547     }
548     filename++;
549 
550     snprintf(label, sizeof(label), "usbserial%d", index++);
551     cdrv = qemu_chr_new(label, filename);
552     if (!cdrv)
553         return NULL;
554 
555     dev = usb_create(bus, "usb-serial");
556     qdev_prop_set_chr(&dev->qdev, "chardev", cdrv);
557     if (vendorid)
558         qdev_prop_set_uint16(&dev->qdev, "vendorid", vendorid);
559     if (productid)
560         qdev_prop_set_uint16(&dev->qdev, "productid", productid);
561     return dev;
562 }
563 
564 static USBDevice *usb_braille_init(USBBus *bus, const char *unused)
565 {
566     USBDevice *dev;
567     Chardev *cdrv;
568 
569     cdrv = qemu_chr_new("braille", "braille");
570     if (!cdrv)
571         return NULL;
572 
573     dev = usb_create(bus, "usb-braille");
574     qdev_prop_set_chr(&dev->qdev, "chardev", cdrv);
575     return dev;
576 }
577 
578 static const VMStateDescription vmstate_usb_serial = {
579     .name = "usb-serial",
580     .unmigratable = 1,
581 };
582 
583 static Property serial_properties[] = {
584     DEFINE_PROP_CHR("chardev", USBSerialState, cs),
585     DEFINE_PROP_END_OF_LIST(),
586 };
587 
588 static void usb_serial_dev_class_init(ObjectClass *klass, void *data)
589 {
590     DeviceClass *dc = DEVICE_CLASS(klass);
591     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
592 
593     uc->realize        = usb_serial_realize;
594     uc->handle_reset   = usb_serial_handle_reset;
595     uc->handle_control = usb_serial_handle_control;
596     uc->handle_data    = usb_serial_handle_data;
597     dc->vmsd = &vmstate_usb_serial;
598     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
599 }
600 
601 static const TypeInfo usb_serial_dev_type_info = {
602     .name = TYPE_USB_SERIAL,
603     .parent = TYPE_USB_DEVICE,
604     .instance_size = sizeof(USBSerialState),
605     .abstract = true,
606     .class_init = usb_serial_dev_class_init,
607 };
608 
609 static void usb_serial_class_initfn(ObjectClass *klass, void *data)
610 {
611     DeviceClass *dc = DEVICE_CLASS(klass);
612     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
613 
614     uc->product_desc   = "QEMU USB Serial";
615     uc->usb_desc       = &desc_serial;
616     dc->props = serial_properties;
617 }
618 
619 static const TypeInfo serial_info = {
620     .name          = "usb-serial",
621     .parent        = TYPE_USB_SERIAL,
622     .class_init    = usb_serial_class_initfn,
623 };
624 
625 static Property braille_properties[] = {
626     DEFINE_PROP_CHR("chardev", USBSerialState, cs),
627     DEFINE_PROP_END_OF_LIST(),
628 };
629 
630 static void usb_braille_class_initfn(ObjectClass *klass, void *data)
631 {
632     DeviceClass *dc = DEVICE_CLASS(klass);
633     USBDeviceClass *uc = USB_DEVICE_CLASS(klass);
634 
635     uc->product_desc   = "QEMU USB Braille";
636     uc->usb_desc       = &desc_braille;
637     dc->props = braille_properties;
638 }
639 
640 static const TypeInfo braille_info = {
641     .name          = "usb-braille",
642     .parent        = TYPE_USB_SERIAL,
643     .class_init    = usb_braille_class_initfn,
644 };
645 
646 static void usb_serial_register_types(void)
647 {
648     type_register_static(&usb_serial_dev_type_info);
649     type_register_static(&serial_info);
650     usb_legacy_register("usb-serial", "serial", usb_serial_init);
651     type_register_static(&braille_info);
652     usb_legacy_register("usb-braille", "braille", usb_braille_init);
653 }
654 
655 type_init(usb_serial_register_types)
656