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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * MCT (Magic Control Technology Corp.) USB RS232 Converter Driver
4 *
5 * Copyright (C) 2000 Wolfgang Grandegger (wolfgang@ces.ch)
6 *
7 * This program is largely derived from the Belkin USB Serial Adapter Driver
8 * (see belkin_sa.[ch]). All of the information about the device was acquired
9 * by using SniffUSB on Windows98. For technical details see mct_u232.h.
10 *
11 * William G. Greathouse and Greg Kroah-Hartman provided great help on how to
12 * do the reverse engineering and how to write a USB serial device driver.
13 *
14 * TO BE DONE, TO BE CHECKED:
15 * DTR/RTS signal handling may be incomplete or incorrect. I have mainly
16 * implemented what I have seen with SniffUSB or found in belkin_sa.c.
17 * For further TODOs check also belkin_sa.c.
18 */
19
20#include <linux/kernel.h>
21#include <linux/errno.h>
22#include <linux/slab.h>
23#include <linux/tty.h>
24#include <linux/tty_driver.h>
25#include <linux/tty_flip.h>
26#include <linux/module.h>
27#include <linux/spinlock.h>
28#include <linux/uaccess.h>
29#include <asm/unaligned.h>
30#include <linux/usb.h>
31#include <linux/usb/serial.h>
32#include <linux/serial.h>
33#include "mct_u232.h"
34
35#define DRIVER_AUTHOR "Wolfgang Grandegger <wolfgang@ces.ch>"
36#define DRIVER_DESC "Magic Control Technology USB-RS232 converter driver"
37
38/*
39 * Function prototypes
40 */
41static int mct_u232_port_probe(struct usb_serial_port *port);
42static void mct_u232_port_remove(struct usb_serial_port *remove);
43static int mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port);
44static void mct_u232_close(struct usb_serial_port *port);
45static void mct_u232_dtr_rts(struct usb_serial_port *port, int on);
46static void mct_u232_read_int_callback(struct urb *urb);
47static void mct_u232_set_termios(struct tty_struct *tty,
48 struct usb_serial_port *port,
49 const struct ktermios *old_termios);
50static int mct_u232_break_ctl(struct tty_struct *tty, int break_state);
51static int mct_u232_tiocmget(struct tty_struct *tty);
52static int mct_u232_tiocmset(struct tty_struct *tty,
53 unsigned int set, unsigned int clear);
54static void mct_u232_throttle(struct tty_struct *tty);
55static void mct_u232_unthrottle(struct tty_struct *tty);
56
57
58/*
59 * All of the device info needed for the MCT USB-RS232 converter.
60 */
61static const struct usb_device_id id_table[] = {
62 { USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
63 { USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
64 { USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
65 { USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
66 { } /* Terminating entry */
67};
68MODULE_DEVICE_TABLE(usb, id_table);
69
70static struct usb_serial_driver mct_u232_device = {
71 .driver = {
72 .owner = THIS_MODULE,
73 .name = "mct_u232",
74 },
75 .description = "MCT U232",
76 .id_table = id_table,
77 .num_ports = 1,
78 .open = mct_u232_open,
79 .close = mct_u232_close,
80 .dtr_rts = mct_u232_dtr_rts,
81 .throttle = mct_u232_throttle,
82 .unthrottle = mct_u232_unthrottle,
83 .read_int_callback = mct_u232_read_int_callback,
84 .set_termios = mct_u232_set_termios,
85 .break_ctl = mct_u232_break_ctl,
86 .tiocmget = mct_u232_tiocmget,
87 .tiocmset = mct_u232_tiocmset,
88 .tiocmiwait = usb_serial_generic_tiocmiwait,
89 .port_probe = mct_u232_port_probe,
90 .port_remove = mct_u232_port_remove,
91 .get_icount = usb_serial_generic_get_icount,
92};
93
94static struct usb_serial_driver * const serial_drivers[] = {
95 &mct_u232_device, NULL
96};
97
98struct mct_u232_private {
99 struct urb *read_urb;
100 spinlock_t lock;
101 unsigned int control_state; /* Modem Line Setting (TIOCM) */
102 unsigned char last_lcr; /* Line Control Register */
103 unsigned char last_lsr; /* Line Status Register */
104 unsigned char last_msr; /* Modem Status Register */
105 unsigned int rx_flags; /* Throttling flags */
106};
107
108#define THROTTLED 0x01
109
110/*
111 * Handle vendor specific USB requests
112 */
113
114#define WDR_TIMEOUT 5000 /* default urb timeout */
115
116/*
117 * Later day 2.6.0-test kernels have new baud rates like B230400 which
118 * we do not know how to support. We ignore them for the moment.
119 */
120static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
121 speed_t value, speed_t *result)
122{
123 *result = value;
124
125 if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
126 || le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
127 switch (value) {
128 case 300:
129 return 0x01;
130 case 600:
131 return 0x02; /* this one not tested */
132 case 1200:
133 return 0x03;
134 case 2400:
135 return 0x04;
136 case 4800:
137 return 0x06;
138 case 9600:
139 return 0x08;
140 case 19200:
141 return 0x09;
142 case 38400:
143 return 0x0a;
144 case 57600:
145 return 0x0b;
146 case 115200:
147 return 0x0c;
148 default:
149 *result = 9600;
150 return 0x08;
151 }
152 } else {
153 /* FIXME: Can we use any divider - should we do
154 divider = 115200/value;
155 real baud = 115200/divider */
156 switch (value) {
157 case 300: break;
158 case 600: break;
159 case 1200: break;
160 case 2400: break;
161 case 4800: break;
162 case 9600: break;
163 case 19200: break;
164 case 38400: break;
165 case 57600: break;
166 case 115200: break;
167 default:
168 value = 9600;
169 *result = 9600;
170 }
171 return 115200/value;
172 }
173}
174
175static int mct_u232_set_baud_rate(struct tty_struct *tty,
176 struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
177{
178 unsigned int divisor;
179 int rc;
180 unsigned char *buf;
181 unsigned char cts_enable_byte = 0;
182 speed_t speed;
183
184 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
185 if (buf == NULL)
186 return -ENOMEM;
187
188 divisor = mct_u232_calculate_baud_rate(serial, value, &speed);
189 put_unaligned_le32(divisor, buf);
190 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
191 MCT_U232_SET_BAUD_RATE_REQUEST,
192 MCT_U232_SET_REQUEST_TYPE,
193 0, 0, buf, MCT_U232_SET_BAUD_RATE_SIZE,
194 WDR_TIMEOUT);
195 if (rc < 0) /*FIXME: What value speed results */
196 dev_err(&port->dev, "Set BAUD RATE %d failed (error = %d)\n",
197 value, rc);
198 else
199 tty_encode_baud_rate(tty, speed, speed);
200 dev_dbg(&port->dev, "set_baud_rate: value: 0x%x, divisor: 0x%x\n", value, divisor);
201
202 /* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
203 always sends two extra USB 'device request' messages after the
204 'baud rate change' message. The actual functionality of the
205 request codes in these messages is not fully understood but these
206 particular codes are never seen in any operation besides a baud
207 rate change. Both of these messages send a single byte of data.
208 In the first message, the value of this byte is always zero.
209
210 The second message has been determined experimentally to control
211 whether data will be transmitted to a device which is not asserting
212 the 'CTS' signal. If the second message's data byte is zero, data
213 will be transmitted even if 'CTS' is not asserted (i.e. no hardware
214 flow control). if the second message's data byte is nonzero (a
215 value of 1 is used by this driver), data will not be transmitted to
216 a device which is not asserting 'CTS'.
217 */
218
219 buf[0] = 0;
220 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
221 MCT_U232_SET_UNKNOWN1_REQUEST,
222 MCT_U232_SET_REQUEST_TYPE,
223 0, 0, buf, MCT_U232_SET_UNKNOWN1_SIZE,
224 WDR_TIMEOUT);
225 if (rc < 0)
226 dev_err(&port->dev, "Sending USB device request code %d "
227 "failed (error = %d)\n", MCT_U232_SET_UNKNOWN1_REQUEST,
228 rc);
229
230 if (port && C_CRTSCTS(tty))
231 cts_enable_byte = 1;
232
233 dev_dbg(&port->dev, "set_baud_rate: send second control message, data = %02X\n",
234 cts_enable_byte);
235 buf[0] = cts_enable_byte;
236 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
237 MCT_U232_SET_CTS_REQUEST,
238 MCT_U232_SET_REQUEST_TYPE,
239 0, 0, buf, MCT_U232_SET_CTS_SIZE,
240 WDR_TIMEOUT);
241 if (rc < 0)
242 dev_err(&port->dev, "Sending USB device request code %d "
243 "failed (error = %d)\n", MCT_U232_SET_CTS_REQUEST, rc);
244
245 kfree(buf);
246 return rc;
247} /* mct_u232_set_baud_rate */
248
249static int mct_u232_set_line_ctrl(struct usb_serial_port *port,
250 unsigned char lcr)
251{
252 int rc;
253 unsigned char *buf;
254
255 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
256 if (buf == NULL)
257 return -ENOMEM;
258
259 buf[0] = lcr;
260 rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
261 MCT_U232_SET_LINE_CTRL_REQUEST,
262 MCT_U232_SET_REQUEST_TYPE,
263 0, 0, buf, MCT_U232_SET_LINE_CTRL_SIZE,
264 WDR_TIMEOUT);
265 if (rc < 0)
266 dev_err(&port->dev, "Set LINE CTRL 0x%x failed (error = %d)\n", lcr, rc);
267 dev_dbg(&port->dev, "set_line_ctrl: 0x%x\n", lcr);
268 kfree(buf);
269 return rc;
270} /* mct_u232_set_line_ctrl */
271
272static int mct_u232_set_modem_ctrl(struct usb_serial_port *port,
273 unsigned int control_state)
274{
275 int rc;
276 unsigned char mcr;
277 unsigned char *buf;
278
279 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
280 if (buf == NULL)
281 return -ENOMEM;
282
283 mcr = MCT_U232_MCR_NONE;
284 if (control_state & TIOCM_DTR)
285 mcr |= MCT_U232_MCR_DTR;
286 if (control_state & TIOCM_RTS)
287 mcr |= MCT_U232_MCR_RTS;
288
289 buf[0] = mcr;
290 rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
291 MCT_U232_SET_MODEM_CTRL_REQUEST,
292 MCT_U232_SET_REQUEST_TYPE,
293 0, 0, buf, MCT_U232_SET_MODEM_CTRL_SIZE,
294 WDR_TIMEOUT);
295 kfree(buf);
296
297 dev_dbg(&port->dev, "set_modem_ctrl: state=0x%x ==> mcr=0x%x\n", control_state, mcr);
298
299 if (rc < 0) {
300 dev_err(&port->dev, "Set MODEM CTRL 0x%x failed (error = %d)\n", mcr, rc);
301 return rc;
302 }
303 return 0;
304} /* mct_u232_set_modem_ctrl */
305
306static int mct_u232_get_modem_stat(struct usb_serial_port *port,
307 unsigned char *msr)
308{
309 int rc;
310 unsigned char *buf;
311
312 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
313 if (buf == NULL) {
314 *msr = 0;
315 return -ENOMEM;
316 }
317 rc = usb_control_msg(port->serial->dev, usb_rcvctrlpipe(port->serial->dev, 0),
318 MCT_U232_GET_MODEM_STAT_REQUEST,
319 MCT_U232_GET_REQUEST_TYPE,
320 0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
321 WDR_TIMEOUT);
322 if (rc < MCT_U232_GET_MODEM_STAT_SIZE) {
323 dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
324
325 if (rc >= 0)
326 rc = -EIO;
327
328 *msr = 0;
329 } else {
330 *msr = buf[0];
331 }
332 dev_dbg(&port->dev, "get_modem_stat: 0x%x\n", *msr);
333 kfree(buf);
334 return rc;
335} /* mct_u232_get_modem_stat */
336
337static void mct_u232_msr_to_icount(struct async_icount *icount,
338 unsigned char msr)
339{
340 /* Translate Control Line states */
341 if (msr & MCT_U232_MSR_DDSR)
342 icount->dsr++;
343 if (msr & MCT_U232_MSR_DCTS)
344 icount->cts++;
345 if (msr & MCT_U232_MSR_DRI)
346 icount->rng++;
347 if (msr & MCT_U232_MSR_DCD)
348 icount->dcd++;
349} /* mct_u232_msr_to_icount */
350
351static void mct_u232_msr_to_state(struct usb_serial_port *port,
352 unsigned int *control_state, unsigned char msr)
353{
354 /* Translate Control Line states */
355 if (msr & MCT_U232_MSR_DSR)
356 *control_state |= TIOCM_DSR;
357 else
358 *control_state &= ~TIOCM_DSR;
359 if (msr & MCT_U232_MSR_CTS)
360 *control_state |= TIOCM_CTS;
361 else
362 *control_state &= ~TIOCM_CTS;
363 if (msr & MCT_U232_MSR_RI)
364 *control_state |= TIOCM_RI;
365 else
366 *control_state &= ~TIOCM_RI;
367 if (msr & MCT_U232_MSR_CD)
368 *control_state |= TIOCM_CD;
369 else
370 *control_state &= ~TIOCM_CD;
371 dev_dbg(&port->dev, "msr_to_state: msr=0x%x ==> state=0x%x\n", msr, *control_state);
372} /* mct_u232_msr_to_state */
373
374/*
375 * Driver's tty interface functions
376 */
377
378static int mct_u232_port_probe(struct usb_serial_port *port)
379{
380 struct usb_serial *serial = port->serial;
381 struct mct_u232_private *priv;
382
383 /* check first to simplify error handling */
384 if (!serial->port[1] || !serial->port[1]->interrupt_in_urb) {
385 dev_err(&port->dev, "expected endpoint missing\n");
386 return -ENODEV;
387 }
388
389 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
390 if (!priv)
391 return -ENOMEM;
392
393 /* Use second interrupt-in endpoint for reading. */
394 priv->read_urb = serial->port[1]->interrupt_in_urb;
395 priv->read_urb->context = port;
396
397 spin_lock_init(&priv->lock);
398
399 usb_set_serial_port_data(port, priv);
400
401 return 0;
402}
403
404static void mct_u232_port_remove(struct usb_serial_port *port)
405{
406 struct mct_u232_private *priv;
407
408 priv = usb_get_serial_port_data(port);
409 kfree(priv);
410}
411
412static int mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
413{
414 struct usb_serial *serial = port->serial;
415 struct mct_u232_private *priv = usb_get_serial_port_data(port);
416 int retval = 0;
417 unsigned int control_state;
418 unsigned long flags;
419 unsigned char last_lcr;
420 unsigned char last_msr;
421
422 /* Compensate for a hardware bug: although the Sitecom U232-P25
423 * device reports a maximum output packet size of 32 bytes,
424 * it seems to be able to accept only 16 bytes (and that's what
425 * SniffUSB says too...)
426 */
427 if (le16_to_cpu(serial->dev->descriptor.idProduct)
428 == MCT_U232_SITECOM_PID)
429 port->bulk_out_size = 16;
430
431 /* Do a defined restart: the normal serial device seems to
432 * always turn on DTR and RTS here, so do the same. I'm not
433 * sure if this is really necessary. But it should not harm
434 * either.
435 */
436 spin_lock_irqsave(&priv->lock, flags);
437 if (tty && C_BAUD(tty))
438 priv->control_state = TIOCM_DTR | TIOCM_RTS;
439 else
440 priv->control_state = 0;
441
442 priv->last_lcr = (MCT_U232_DATA_BITS_8 |
443 MCT_U232_PARITY_NONE |
444 MCT_U232_STOP_BITS_1);
445 control_state = priv->control_state;
446 last_lcr = priv->last_lcr;
447 spin_unlock_irqrestore(&priv->lock, flags);
448 mct_u232_set_modem_ctrl(port, control_state);
449 mct_u232_set_line_ctrl(port, last_lcr);
450
451 /* Read modem status and update control state */
452 mct_u232_get_modem_stat(port, &last_msr);
453 spin_lock_irqsave(&priv->lock, flags);
454 priv->last_msr = last_msr;
455 mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
456 spin_unlock_irqrestore(&priv->lock, flags);
457
458 retval = usb_submit_urb(priv->read_urb, GFP_KERNEL);
459 if (retval) {
460 dev_err(&port->dev,
461 "usb_submit_urb(read) failed pipe 0x%x err %d\n",
462 port->read_urb->pipe, retval);
463 goto error;
464 }
465
466 retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
467 if (retval) {
468 usb_kill_urb(priv->read_urb);
469 dev_err(&port->dev,
470 "usb_submit_urb(read int) failed pipe 0x%x err %d",
471 port->interrupt_in_urb->pipe, retval);
472 goto error;
473 }
474 return 0;
475
476error:
477 return retval;
478} /* mct_u232_open */
479
480static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
481{
482 unsigned int control_state;
483 struct mct_u232_private *priv = usb_get_serial_port_data(port);
484
485 spin_lock_irq(&priv->lock);
486 if (on)
487 priv->control_state |= TIOCM_DTR | TIOCM_RTS;
488 else
489 priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
490 control_state = priv->control_state;
491 spin_unlock_irq(&priv->lock);
492
493 mct_u232_set_modem_ctrl(port, control_state);
494}
495
496static void mct_u232_close(struct usb_serial_port *port)
497{
498 struct mct_u232_private *priv = usb_get_serial_port_data(port);
499
500 usb_kill_urb(priv->read_urb);
501 usb_kill_urb(port->interrupt_in_urb);
502
503 usb_serial_generic_close(port);
504} /* mct_u232_close */
505
506
507static void mct_u232_read_int_callback(struct urb *urb)
508{
509 struct usb_serial_port *port = urb->context;
510 struct mct_u232_private *priv = usb_get_serial_port_data(port);
511 unsigned char *data = urb->transfer_buffer;
512 int retval;
513 int status = urb->status;
514 unsigned long flags;
515
516 switch (status) {
517 case 0:
518 /* success */
519 break;
520 case -ECONNRESET:
521 case -ENOENT:
522 case -ESHUTDOWN:
523 /* this urb is terminated, clean up */
524 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
525 __func__, status);
526 return;
527 default:
528 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
529 __func__, status);
530 goto exit;
531 }
532
533 usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
534
535 /*
536 * Work-a-round: handle the 'usual' bulk-in pipe here
537 */
538 if (urb->transfer_buffer_length > 2) {
539 if (urb->actual_length) {
540 tty_insert_flip_string(&port->port, data,
541 urb->actual_length);
542 tty_flip_buffer_push(&port->port);
543 }
544 goto exit;
545 }
546
547 /*
548 * The interrupt-in pipe signals exceptional conditions (modem line
549 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
550 */
551 spin_lock_irqsave(&priv->lock, flags);
552 priv->last_msr = data[MCT_U232_MSR_INDEX];
553
554 /* Record Control Line states */
555 mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
556
557 mct_u232_msr_to_icount(&port->icount, priv->last_msr);
558
559#if 0
560 /* Not yet handled. See belkin_sa.c for further information */
561 /* Now to report any errors */
562 priv->last_lsr = data[MCT_U232_LSR_INDEX];
563 /*
564 * fill in the flip buffer here, but I do not know the relation
565 * to the current/next receive buffer or characters. I need
566 * to look in to this before committing any code.
567 */
568 if (priv->last_lsr & MCT_U232_LSR_ERR) {
569 tty = tty_port_tty_get(&port->port);
570 /* Overrun Error */
571 if (priv->last_lsr & MCT_U232_LSR_OE) {
572 }
573 /* Parity Error */
574 if (priv->last_lsr & MCT_U232_LSR_PE) {
575 }
576 /* Framing Error */
577 if (priv->last_lsr & MCT_U232_LSR_FE) {
578 }
579 /* Break Indicator */
580 if (priv->last_lsr & MCT_U232_LSR_BI) {
581 }
582 tty_kref_put(tty);
583 }
584#endif
585 wake_up_interruptible(&port->port.delta_msr_wait);
586 spin_unlock_irqrestore(&priv->lock, flags);
587exit:
588 retval = usb_submit_urb(urb, GFP_ATOMIC);
589 if (retval)
590 dev_err(&port->dev,
591 "%s - usb_submit_urb failed with result %d\n",
592 __func__, retval);
593} /* mct_u232_read_int_callback */
594
595static void mct_u232_set_termios(struct tty_struct *tty,
596 struct usb_serial_port *port,
597 const struct ktermios *old_termios)
598{
599 struct usb_serial *serial = port->serial;
600 struct mct_u232_private *priv = usb_get_serial_port_data(port);
601 struct ktermios *termios = &tty->termios;
602 unsigned int cflag = termios->c_cflag;
603 unsigned int old_cflag = old_termios->c_cflag;
604 unsigned long flags;
605 unsigned int control_state;
606 unsigned char last_lcr;
607
608 /* get a local copy of the current port settings */
609 spin_lock_irqsave(&priv->lock, flags);
610 control_state = priv->control_state;
611 spin_unlock_irqrestore(&priv->lock, flags);
612 last_lcr = 0;
613
614 /*
615 * Update baud rate.
616 * Do not attempt to cache old rates and skip settings,
617 * disconnects screw such tricks up completely.
618 * Premature optimization is the root of all evil.
619 */
620
621 /* reassert DTR and RTS on transition from B0 */
622 if ((old_cflag & CBAUD) == B0) {
623 dev_dbg(&port->dev, "%s: baud was B0\n", __func__);
624 control_state |= TIOCM_DTR | TIOCM_RTS;
625 mct_u232_set_modem_ctrl(port, control_state);
626 }
627
628 mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
629
630 if ((cflag & CBAUD) == B0) {
631 dev_dbg(&port->dev, "%s: baud is B0\n", __func__);
632 /* Drop RTS and DTR */
633 control_state &= ~(TIOCM_DTR | TIOCM_RTS);
634 mct_u232_set_modem_ctrl(port, control_state);
635 }
636
637 /*
638 * Update line control register (LCR)
639 */
640
641 /* set the parity */
642 if (cflag & PARENB)
643 last_lcr |= (cflag & PARODD) ?
644 MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
645 else
646 last_lcr |= MCT_U232_PARITY_NONE;
647
648 /* set the number of data bits */
649 switch (cflag & CSIZE) {
650 case CS5:
651 last_lcr |= MCT_U232_DATA_BITS_5; break;
652 case CS6:
653 last_lcr |= MCT_U232_DATA_BITS_6; break;
654 case CS7:
655 last_lcr |= MCT_U232_DATA_BITS_7; break;
656 case CS8:
657 last_lcr |= MCT_U232_DATA_BITS_8; break;
658 default:
659 dev_err(&port->dev,
660 "CSIZE was not CS5-CS8, using default of 8\n");
661 last_lcr |= MCT_U232_DATA_BITS_8;
662 break;
663 }
664
665 termios->c_cflag &= ~CMSPAR;
666
667 /* set the number of stop bits */
668 last_lcr |= (cflag & CSTOPB) ?
669 MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
670
671 mct_u232_set_line_ctrl(port, last_lcr);
672
673 /* save off the modified port settings */
674 spin_lock_irqsave(&priv->lock, flags);
675 priv->control_state = control_state;
676 priv->last_lcr = last_lcr;
677 spin_unlock_irqrestore(&priv->lock, flags);
678} /* mct_u232_set_termios */
679
680static int mct_u232_break_ctl(struct tty_struct *tty, int break_state)
681{
682 struct usb_serial_port *port = tty->driver_data;
683 struct mct_u232_private *priv = usb_get_serial_port_data(port);
684 unsigned char lcr;
685 unsigned long flags;
686
687 spin_lock_irqsave(&priv->lock, flags);
688 lcr = priv->last_lcr;
689
690 if (break_state)
691 lcr |= MCT_U232_SET_BREAK;
692 spin_unlock_irqrestore(&priv->lock, flags);
693
694 return mct_u232_set_line_ctrl(port, lcr);
695} /* mct_u232_break_ctl */
696
697
698static int mct_u232_tiocmget(struct tty_struct *tty)
699{
700 struct usb_serial_port *port = tty->driver_data;
701 struct mct_u232_private *priv = usb_get_serial_port_data(port);
702 unsigned int control_state;
703 unsigned long flags;
704
705 spin_lock_irqsave(&priv->lock, flags);
706 control_state = priv->control_state;
707 spin_unlock_irqrestore(&priv->lock, flags);
708
709 return control_state;
710}
711
712static int mct_u232_tiocmset(struct tty_struct *tty,
713 unsigned int set, unsigned int clear)
714{
715 struct usb_serial_port *port = tty->driver_data;
716 struct mct_u232_private *priv = usb_get_serial_port_data(port);
717 unsigned int control_state;
718 unsigned long flags;
719
720 spin_lock_irqsave(&priv->lock, flags);
721 control_state = priv->control_state;
722
723 if (set & TIOCM_RTS)
724 control_state |= TIOCM_RTS;
725 if (set & TIOCM_DTR)
726 control_state |= TIOCM_DTR;
727 if (clear & TIOCM_RTS)
728 control_state &= ~TIOCM_RTS;
729 if (clear & TIOCM_DTR)
730 control_state &= ~TIOCM_DTR;
731
732 priv->control_state = control_state;
733 spin_unlock_irqrestore(&priv->lock, flags);
734 return mct_u232_set_modem_ctrl(port, control_state);
735}
736
737static void mct_u232_throttle(struct tty_struct *tty)
738{
739 struct usb_serial_port *port = tty->driver_data;
740 struct mct_u232_private *priv = usb_get_serial_port_data(port);
741 unsigned int control_state;
742
743 spin_lock_irq(&priv->lock);
744 priv->rx_flags |= THROTTLED;
745 if (C_CRTSCTS(tty)) {
746 priv->control_state &= ~TIOCM_RTS;
747 control_state = priv->control_state;
748 spin_unlock_irq(&priv->lock);
749 mct_u232_set_modem_ctrl(port, control_state);
750 } else {
751 spin_unlock_irq(&priv->lock);
752 }
753}
754
755static void mct_u232_unthrottle(struct tty_struct *tty)
756{
757 struct usb_serial_port *port = tty->driver_data;
758 struct mct_u232_private *priv = usb_get_serial_port_data(port);
759 unsigned int control_state;
760
761 spin_lock_irq(&priv->lock);
762 if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
763 priv->rx_flags &= ~THROTTLED;
764 priv->control_state |= TIOCM_RTS;
765 control_state = priv->control_state;
766 spin_unlock_irq(&priv->lock);
767 mct_u232_set_modem_ctrl(port, control_state);
768 } else {
769 spin_unlock_irq(&priv->lock);
770 }
771}
772
773module_usb_serial_driver(serial_drivers, id_table);
774
775MODULE_AUTHOR(DRIVER_AUTHOR);
776MODULE_DESCRIPTION(DRIVER_DESC);
777MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * MCT (Magic Control Technology Corp.) USB RS232 Converter Driver
4 *
5 * Copyright (C) 2000 Wolfgang Grandegger (wolfgang@ces.ch)
6 *
7 * This program is largely derived from the Belkin USB Serial Adapter Driver
8 * (see belkin_sa.[ch]). All of the information about the device was acquired
9 * by using SniffUSB on Windows98. For technical details see mct_u232.h.
10 *
11 * William G. Greathouse and Greg Kroah-Hartman provided great help on how to
12 * do the reverse engineering and how to write a USB serial device driver.
13 *
14 * TO BE DONE, TO BE CHECKED:
15 * DTR/RTS signal handling may be incomplete or incorrect. I have mainly
16 * implemented what I have seen with SniffUSB or found in belkin_sa.c.
17 * For further TODOs check also belkin_sa.c.
18 */
19
20#include <linux/kernel.h>
21#include <linux/errno.h>
22#include <linux/slab.h>
23#include <linux/tty.h>
24#include <linux/tty_driver.h>
25#include <linux/tty_flip.h>
26#include <linux/module.h>
27#include <linux/spinlock.h>
28#include <linux/uaccess.h>
29#include <linux/unaligned.h>
30#include <linux/usb.h>
31#include <linux/usb/serial.h>
32#include <linux/serial.h>
33#include "mct_u232.h"
34
35#define DRIVER_AUTHOR "Wolfgang Grandegger <wolfgang@ces.ch>"
36#define DRIVER_DESC "Magic Control Technology USB-RS232 converter driver"
37
38/*
39 * Function prototypes
40 */
41static int mct_u232_port_probe(struct usb_serial_port *port);
42static void mct_u232_port_remove(struct usb_serial_port *remove);
43static int mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port);
44static void mct_u232_close(struct usb_serial_port *port);
45static void mct_u232_dtr_rts(struct usb_serial_port *port, int on);
46static void mct_u232_read_int_callback(struct urb *urb);
47static void mct_u232_set_termios(struct tty_struct *tty,
48 struct usb_serial_port *port,
49 const struct ktermios *old_termios);
50static int mct_u232_break_ctl(struct tty_struct *tty, int break_state);
51static int mct_u232_tiocmget(struct tty_struct *tty);
52static int mct_u232_tiocmset(struct tty_struct *tty,
53 unsigned int set, unsigned int clear);
54static void mct_u232_throttle(struct tty_struct *tty);
55static void mct_u232_unthrottle(struct tty_struct *tty);
56
57
58/*
59 * All of the device info needed for the MCT USB-RS232 converter.
60 */
61static const struct usb_device_id id_table[] = {
62 { USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
63 { USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
64 { USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
65 { USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
66 { } /* Terminating entry */
67};
68MODULE_DEVICE_TABLE(usb, id_table);
69
70static struct usb_serial_driver mct_u232_device = {
71 .driver = {
72 .name = "mct_u232",
73 },
74 .description = "MCT U232",
75 .id_table = id_table,
76 .num_ports = 1,
77 .open = mct_u232_open,
78 .close = mct_u232_close,
79 .dtr_rts = mct_u232_dtr_rts,
80 .throttle = mct_u232_throttle,
81 .unthrottle = mct_u232_unthrottle,
82 .read_int_callback = mct_u232_read_int_callback,
83 .set_termios = mct_u232_set_termios,
84 .break_ctl = mct_u232_break_ctl,
85 .tiocmget = mct_u232_tiocmget,
86 .tiocmset = mct_u232_tiocmset,
87 .tiocmiwait = usb_serial_generic_tiocmiwait,
88 .port_probe = mct_u232_port_probe,
89 .port_remove = mct_u232_port_remove,
90 .get_icount = usb_serial_generic_get_icount,
91};
92
93static struct usb_serial_driver * const serial_drivers[] = {
94 &mct_u232_device, NULL
95};
96
97struct mct_u232_private {
98 struct urb *read_urb;
99 spinlock_t lock;
100 unsigned int control_state; /* Modem Line Setting (TIOCM) */
101 unsigned char last_lcr; /* Line Control Register */
102 unsigned char last_lsr; /* Line Status Register */
103 unsigned char last_msr; /* Modem Status Register */
104 unsigned int rx_flags; /* Throttling flags */
105};
106
107#define THROTTLED 0x01
108
109/*
110 * Handle vendor specific USB requests
111 */
112
113#define WDR_TIMEOUT 5000 /* default urb timeout */
114
115/*
116 * Later day 2.6.0-test kernels have new baud rates like B230400 which
117 * we do not know how to support. We ignore them for the moment.
118 */
119static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
120 speed_t value, speed_t *result)
121{
122 *result = value;
123
124 if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
125 || le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
126 switch (value) {
127 case 300:
128 return 0x01;
129 case 600:
130 return 0x02; /* this one not tested */
131 case 1200:
132 return 0x03;
133 case 2400:
134 return 0x04;
135 case 4800:
136 return 0x06;
137 case 9600:
138 return 0x08;
139 case 19200:
140 return 0x09;
141 case 38400:
142 return 0x0a;
143 case 57600:
144 return 0x0b;
145 case 115200:
146 return 0x0c;
147 default:
148 *result = 9600;
149 return 0x08;
150 }
151 } else {
152 /* FIXME: Can we use any divider - should we do
153 divider = 115200/value;
154 real baud = 115200/divider */
155 switch (value) {
156 case 300: break;
157 case 600: break;
158 case 1200: break;
159 case 2400: break;
160 case 4800: break;
161 case 9600: break;
162 case 19200: break;
163 case 38400: break;
164 case 57600: break;
165 case 115200: break;
166 default:
167 value = 9600;
168 *result = 9600;
169 }
170 return 115200/value;
171 }
172}
173
174static int mct_u232_set_baud_rate(struct tty_struct *tty,
175 struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
176{
177 unsigned int divisor;
178 int rc;
179 unsigned char *buf;
180 unsigned char cts_enable_byte = 0;
181 speed_t speed;
182
183 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
184 if (buf == NULL)
185 return -ENOMEM;
186
187 divisor = mct_u232_calculate_baud_rate(serial, value, &speed);
188 put_unaligned_le32(divisor, buf);
189 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
190 MCT_U232_SET_BAUD_RATE_REQUEST,
191 MCT_U232_SET_REQUEST_TYPE,
192 0, 0, buf, MCT_U232_SET_BAUD_RATE_SIZE,
193 WDR_TIMEOUT);
194 if (rc < 0) /*FIXME: What value speed results */
195 dev_err(&port->dev, "Set BAUD RATE %d failed (error = %d)\n",
196 value, rc);
197 else
198 tty_encode_baud_rate(tty, speed, speed);
199 dev_dbg(&port->dev, "set_baud_rate: value: 0x%x, divisor: 0x%x\n", value, divisor);
200
201 /* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
202 always sends two extra USB 'device request' messages after the
203 'baud rate change' message. The actual functionality of the
204 request codes in these messages is not fully understood but these
205 particular codes are never seen in any operation besides a baud
206 rate change. Both of these messages send a single byte of data.
207 In the first message, the value of this byte is always zero.
208
209 The second message has been determined experimentally to control
210 whether data will be transmitted to a device which is not asserting
211 the 'CTS' signal. If the second message's data byte is zero, data
212 will be transmitted even if 'CTS' is not asserted (i.e. no hardware
213 flow control). if the second message's data byte is nonzero (a
214 value of 1 is used by this driver), data will not be transmitted to
215 a device which is not asserting 'CTS'.
216 */
217
218 buf[0] = 0;
219 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
220 MCT_U232_SET_UNKNOWN1_REQUEST,
221 MCT_U232_SET_REQUEST_TYPE,
222 0, 0, buf, MCT_U232_SET_UNKNOWN1_SIZE,
223 WDR_TIMEOUT);
224 if (rc < 0)
225 dev_err(&port->dev, "Sending USB device request code %d "
226 "failed (error = %d)\n", MCT_U232_SET_UNKNOWN1_REQUEST,
227 rc);
228
229 if (port && C_CRTSCTS(tty))
230 cts_enable_byte = 1;
231
232 dev_dbg(&port->dev, "set_baud_rate: send second control message, data = %02X\n",
233 cts_enable_byte);
234 buf[0] = cts_enable_byte;
235 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
236 MCT_U232_SET_CTS_REQUEST,
237 MCT_U232_SET_REQUEST_TYPE,
238 0, 0, buf, MCT_U232_SET_CTS_SIZE,
239 WDR_TIMEOUT);
240 if (rc < 0)
241 dev_err(&port->dev, "Sending USB device request code %d "
242 "failed (error = %d)\n", MCT_U232_SET_CTS_REQUEST, rc);
243
244 kfree(buf);
245 return rc;
246} /* mct_u232_set_baud_rate */
247
248static int mct_u232_set_line_ctrl(struct usb_serial_port *port,
249 unsigned char lcr)
250{
251 int rc;
252 unsigned char *buf;
253
254 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
255 if (buf == NULL)
256 return -ENOMEM;
257
258 buf[0] = lcr;
259 rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
260 MCT_U232_SET_LINE_CTRL_REQUEST,
261 MCT_U232_SET_REQUEST_TYPE,
262 0, 0, buf, MCT_U232_SET_LINE_CTRL_SIZE,
263 WDR_TIMEOUT);
264 if (rc < 0)
265 dev_err(&port->dev, "Set LINE CTRL 0x%x failed (error = %d)\n", lcr, rc);
266 dev_dbg(&port->dev, "set_line_ctrl: 0x%x\n", lcr);
267 kfree(buf);
268 return rc;
269} /* mct_u232_set_line_ctrl */
270
271static int mct_u232_set_modem_ctrl(struct usb_serial_port *port,
272 unsigned int control_state)
273{
274 int rc;
275 unsigned char mcr;
276 unsigned char *buf;
277
278 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
279 if (buf == NULL)
280 return -ENOMEM;
281
282 mcr = MCT_U232_MCR_NONE;
283 if (control_state & TIOCM_DTR)
284 mcr |= MCT_U232_MCR_DTR;
285 if (control_state & TIOCM_RTS)
286 mcr |= MCT_U232_MCR_RTS;
287
288 buf[0] = mcr;
289 rc = usb_control_msg(port->serial->dev, usb_sndctrlpipe(port->serial->dev, 0),
290 MCT_U232_SET_MODEM_CTRL_REQUEST,
291 MCT_U232_SET_REQUEST_TYPE,
292 0, 0, buf, MCT_U232_SET_MODEM_CTRL_SIZE,
293 WDR_TIMEOUT);
294 kfree(buf);
295
296 dev_dbg(&port->dev, "set_modem_ctrl: state=0x%x ==> mcr=0x%x\n", control_state, mcr);
297
298 if (rc < 0) {
299 dev_err(&port->dev, "Set MODEM CTRL 0x%x failed (error = %d)\n", mcr, rc);
300 return rc;
301 }
302 return 0;
303} /* mct_u232_set_modem_ctrl */
304
305static int mct_u232_get_modem_stat(struct usb_serial_port *port,
306 unsigned char *msr)
307{
308 int rc;
309 unsigned char *buf;
310
311 buf = kmalloc(MCT_U232_MAX_SIZE, GFP_KERNEL);
312 if (buf == NULL) {
313 *msr = 0;
314 return -ENOMEM;
315 }
316 rc = usb_control_msg(port->serial->dev, usb_rcvctrlpipe(port->serial->dev, 0),
317 MCT_U232_GET_MODEM_STAT_REQUEST,
318 MCT_U232_GET_REQUEST_TYPE,
319 0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
320 WDR_TIMEOUT);
321 if (rc < MCT_U232_GET_MODEM_STAT_SIZE) {
322 dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
323
324 if (rc >= 0)
325 rc = -EIO;
326
327 *msr = 0;
328 } else {
329 *msr = buf[0];
330 }
331 dev_dbg(&port->dev, "get_modem_stat: 0x%x\n", *msr);
332 kfree(buf);
333 return rc;
334} /* mct_u232_get_modem_stat */
335
336static void mct_u232_msr_to_icount(struct async_icount *icount,
337 unsigned char msr)
338{
339 /* Translate Control Line states */
340 if (msr & MCT_U232_MSR_DDSR)
341 icount->dsr++;
342 if (msr & MCT_U232_MSR_DCTS)
343 icount->cts++;
344 if (msr & MCT_U232_MSR_DRI)
345 icount->rng++;
346 if (msr & MCT_U232_MSR_DCD)
347 icount->dcd++;
348} /* mct_u232_msr_to_icount */
349
350static void mct_u232_msr_to_state(struct usb_serial_port *port,
351 unsigned int *control_state, unsigned char msr)
352{
353 /* Translate Control Line states */
354 if (msr & MCT_U232_MSR_DSR)
355 *control_state |= TIOCM_DSR;
356 else
357 *control_state &= ~TIOCM_DSR;
358 if (msr & MCT_U232_MSR_CTS)
359 *control_state |= TIOCM_CTS;
360 else
361 *control_state &= ~TIOCM_CTS;
362 if (msr & MCT_U232_MSR_RI)
363 *control_state |= TIOCM_RI;
364 else
365 *control_state &= ~TIOCM_RI;
366 if (msr & MCT_U232_MSR_CD)
367 *control_state |= TIOCM_CD;
368 else
369 *control_state &= ~TIOCM_CD;
370 dev_dbg(&port->dev, "msr_to_state: msr=0x%x ==> state=0x%x\n", msr, *control_state);
371} /* mct_u232_msr_to_state */
372
373/*
374 * Driver's tty interface functions
375 */
376
377static int mct_u232_port_probe(struct usb_serial_port *port)
378{
379 struct usb_serial *serial = port->serial;
380 struct mct_u232_private *priv;
381
382 /* check first to simplify error handling */
383 if (!serial->port[1] || !serial->port[1]->interrupt_in_urb) {
384 dev_err(&port->dev, "expected endpoint missing\n");
385 return -ENODEV;
386 }
387
388 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
389 if (!priv)
390 return -ENOMEM;
391
392 /* Use second interrupt-in endpoint for reading. */
393 priv->read_urb = serial->port[1]->interrupt_in_urb;
394 priv->read_urb->context = port;
395
396 spin_lock_init(&priv->lock);
397
398 usb_set_serial_port_data(port, priv);
399
400 return 0;
401}
402
403static void mct_u232_port_remove(struct usb_serial_port *port)
404{
405 struct mct_u232_private *priv;
406
407 priv = usb_get_serial_port_data(port);
408 kfree(priv);
409}
410
411static int mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
412{
413 struct usb_serial *serial = port->serial;
414 struct mct_u232_private *priv = usb_get_serial_port_data(port);
415 int retval = 0;
416 unsigned int control_state;
417 unsigned long flags;
418 unsigned char last_lcr;
419 unsigned char last_msr;
420
421 /* Compensate for a hardware bug: although the Sitecom U232-P25
422 * device reports a maximum output packet size of 32 bytes,
423 * it seems to be able to accept only 16 bytes (and that's what
424 * SniffUSB says too...)
425 */
426 if (le16_to_cpu(serial->dev->descriptor.idProduct)
427 == MCT_U232_SITECOM_PID)
428 port->bulk_out_size = 16;
429
430 /* Do a defined restart: the normal serial device seems to
431 * always turn on DTR and RTS here, so do the same. I'm not
432 * sure if this is really necessary. But it should not harm
433 * either.
434 */
435 spin_lock_irqsave(&priv->lock, flags);
436 if (tty && C_BAUD(tty))
437 priv->control_state = TIOCM_DTR | TIOCM_RTS;
438 else
439 priv->control_state = 0;
440
441 priv->last_lcr = (MCT_U232_DATA_BITS_8 |
442 MCT_U232_PARITY_NONE |
443 MCT_U232_STOP_BITS_1);
444 control_state = priv->control_state;
445 last_lcr = priv->last_lcr;
446 spin_unlock_irqrestore(&priv->lock, flags);
447 mct_u232_set_modem_ctrl(port, control_state);
448 mct_u232_set_line_ctrl(port, last_lcr);
449
450 /* Read modem status and update control state */
451 mct_u232_get_modem_stat(port, &last_msr);
452 spin_lock_irqsave(&priv->lock, flags);
453 priv->last_msr = last_msr;
454 mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
455 spin_unlock_irqrestore(&priv->lock, flags);
456
457 retval = usb_submit_urb(priv->read_urb, GFP_KERNEL);
458 if (retval) {
459 dev_err(&port->dev,
460 "usb_submit_urb(read) failed pipe 0x%x err %d\n",
461 port->read_urb->pipe, retval);
462 goto error;
463 }
464
465 retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
466 if (retval) {
467 usb_kill_urb(priv->read_urb);
468 dev_err(&port->dev,
469 "usb_submit_urb(read int) failed pipe 0x%x err %d",
470 port->interrupt_in_urb->pipe, retval);
471 goto error;
472 }
473 return 0;
474
475error:
476 return retval;
477} /* mct_u232_open */
478
479static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
480{
481 unsigned int control_state;
482 struct mct_u232_private *priv = usb_get_serial_port_data(port);
483
484 spin_lock_irq(&priv->lock);
485 if (on)
486 priv->control_state |= TIOCM_DTR | TIOCM_RTS;
487 else
488 priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
489 control_state = priv->control_state;
490 spin_unlock_irq(&priv->lock);
491
492 mct_u232_set_modem_ctrl(port, control_state);
493}
494
495static void mct_u232_close(struct usb_serial_port *port)
496{
497 struct mct_u232_private *priv = usb_get_serial_port_data(port);
498
499 usb_kill_urb(priv->read_urb);
500 usb_kill_urb(port->interrupt_in_urb);
501
502 usb_serial_generic_close(port);
503} /* mct_u232_close */
504
505
506static void mct_u232_read_int_callback(struct urb *urb)
507{
508 struct usb_serial_port *port = urb->context;
509 struct mct_u232_private *priv = usb_get_serial_port_data(port);
510 unsigned char *data = urb->transfer_buffer;
511 int retval;
512 int status = urb->status;
513 unsigned long flags;
514
515 switch (status) {
516 case 0:
517 /* success */
518 break;
519 case -ECONNRESET:
520 case -ENOENT:
521 case -ESHUTDOWN:
522 /* this urb is terminated, clean up */
523 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
524 __func__, status);
525 return;
526 default:
527 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
528 __func__, status);
529 goto exit;
530 }
531
532 usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
533
534 /*
535 * Work-a-round: handle the 'usual' bulk-in pipe here
536 */
537 if (urb->transfer_buffer_length > 2) {
538 if (urb->actual_length) {
539 tty_insert_flip_string(&port->port, data,
540 urb->actual_length);
541 tty_flip_buffer_push(&port->port);
542 }
543 goto exit;
544 }
545
546 /*
547 * The interrupt-in pipe signals exceptional conditions (modem line
548 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
549 */
550 spin_lock_irqsave(&priv->lock, flags);
551 priv->last_msr = data[MCT_U232_MSR_INDEX];
552
553 /* Record Control Line states */
554 mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
555
556 mct_u232_msr_to_icount(&port->icount, priv->last_msr);
557
558#if 0
559 /* Not yet handled. See belkin_sa.c for further information */
560 /* Now to report any errors */
561 priv->last_lsr = data[MCT_U232_LSR_INDEX];
562 /*
563 * fill in the flip buffer here, but I do not know the relation
564 * to the current/next receive buffer or characters. I need
565 * to look in to this before committing any code.
566 */
567 if (priv->last_lsr & MCT_U232_LSR_ERR) {
568 tty = tty_port_tty_get(&port->port);
569 /* Overrun Error */
570 if (priv->last_lsr & MCT_U232_LSR_OE) {
571 }
572 /* Parity Error */
573 if (priv->last_lsr & MCT_U232_LSR_PE) {
574 }
575 /* Framing Error */
576 if (priv->last_lsr & MCT_U232_LSR_FE) {
577 }
578 /* Break Indicator */
579 if (priv->last_lsr & MCT_U232_LSR_BI) {
580 }
581 tty_kref_put(tty);
582 }
583#endif
584 wake_up_interruptible(&port->port.delta_msr_wait);
585 spin_unlock_irqrestore(&priv->lock, flags);
586exit:
587 retval = usb_submit_urb(urb, GFP_ATOMIC);
588 if (retval)
589 dev_err(&port->dev,
590 "%s - usb_submit_urb failed with result %d\n",
591 __func__, retval);
592} /* mct_u232_read_int_callback */
593
594static void mct_u232_set_termios(struct tty_struct *tty,
595 struct usb_serial_port *port,
596 const struct ktermios *old_termios)
597{
598 struct usb_serial *serial = port->serial;
599 struct mct_u232_private *priv = usb_get_serial_port_data(port);
600 struct ktermios *termios = &tty->termios;
601 unsigned int cflag = termios->c_cflag;
602 unsigned int old_cflag = old_termios->c_cflag;
603 unsigned long flags;
604 unsigned int control_state;
605 unsigned char last_lcr;
606
607 /* get a local copy of the current port settings */
608 spin_lock_irqsave(&priv->lock, flags);
609 control_state = priv->control_state;
610 spin_unlock_irqrestore(&priv->lock, flags);
611 last_lcr = 0;
612
613 /*
614 * Update baud rate.
615 * Do not attempt to cache old rates and skip settings,
616 * disconnects screw such tricks up completely.
617 * Premature optimization is the root of all evil.
618 */
619
620 /* reassert DTR and RTS on transition from B0 */
621 if ((old_cflag & CBAUD) == B0) {
622 dev_dbg(&port->dev, "%s: baud was B0\n", __func__);
623 control_state |= TIOCM_DTR | TIOCM_RTS;
624 mct_u232_set_modem_ctrl(port, control_state);
625 }
626
627 mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
628
629 if ((cflag & CBAUD) == B0) {
630 dev_dbg(&port->dev, "%s: baud is B0\n", __func__);
631 /* Drop RTS and DTR */
632 control_state &= ~(TIOCM_DTR | TIOCM_RTS);
633 mct_u232_set_modem_ctrl(port, control_state);
634 }
635
636 /*
637 * Update line control register (LCR)
638 */
639
640 /* set the parity */
641 if (cflag & PARENB)
642 last_lcr |= (cflag & PARODD) ?
643 MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
644 else
645 last_lcr |= MCT_U232_PARITY_NONE;
646
647 /* set the number of data bits */
648 switch (cflag & CSIZE) {
649 case CS5:
650 last_lcr |= MCT_U232_DATA_BITS_5; break;
651 case CS6:
652 last_lcr |= MCT_U232_DATA_BITS_6; break;
653 case CS7:
654 last_lcr |= MCT_U232_DATA_BITS_7; break;
655 case CS8:
656 last_lcr |= MCT_U232_DATA_BITS_8; break;
657 default:
658 dev_err(&port->dev,
659 "CSIZE was not CS5-CS8, using default of 8\n");
660 last_lcr |= MCT_U232_DATA_BITS_8;
661 break;
662 }
663
664 termios->c_cflag &= ~CMSPAR;
665
666 /* set the number of stop bits */
667 last_lcr |= (cflag & CSTOPB) ?
668 MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
669
670 mct_u232_set_line_ctrl(port, last_lcr);
671
672 /* save off the modified port settings */
673 spin_lock_irqsave(&priv->lock, flags);
674 priv->control_state = control_state;
675 priv->last_lcr = last_lcr;
676 spin_unlock_irqrestore(&priv->lock, flags);
677} /* mct_u232_set_termios */
678
679static int mct_u232_break_ctl(struct tty_struct *tty, int break_state)
680{
681 struct usb_serial_port *port = tty->driver_data;
682 struct mct_u232_private *priv = usb_get_serial_port_data(port);
683 unsigned char lcr;
684 unsigned long flags;
685
686 spin_lock_irqsave(&priv->lock, flags);
687 lcr = priv->last_lcr;
688
689 if (break_state)
690 lcr |= MCT_U232_SET_BREAK;
691 spin_unlock_irqrestore(&priv->lock, flags);
692
693 return mct_u232_set_line_ctrl(port, lcr);
694} /* mct_u232_break_ctl */
695
696
697static int mct_u232_tiocmget(struct tty_struct *tty)
698{
699 struct usb_serial_port *port = tty->driver_data;
700 struct mct_u232_private *priv = usb_get_serial_port_data(port);
701 unsigned int control_state;
702 unsigned long flags;
703
704 spin_lock_irqsave(&priv->lock, flags);
705 control_state = priv->control_state;
706 spin_unlock_irqrestore(&priv->lock, flags);
707
708 return control_state;
709}
710
711static int mct_u232_tiocmset(struct tty_struct *tty,
712 unsigned int set, unsigned int clear)
713{
714 struct usb_serial_port *port = tty->driver_data;
715 struct mct_u232_private *priv = usb_get_serial_port_data(port);
716 unsigned int control_state;
717 unsigned long flags;
718
719 spin_lock_irqsave(&priv->lock, flags);
720 control_state = priv->control_state;
721
722 if (set & TIOCM_RTS)
723 control_state |= TIOCM_RTS;
724 if (set & TIOCM_DTR)
725 control_state |= TIOCM_DTR;
726 if (clear & TIOCM_RTS)
727 control_state &= ~TIOCM_RTS;
728 if (clear & TIOCM_DTR)
729 control_state &= ~TIOCM_DTR;
730
731 priv->control_state = control_state;
732 spin_unlock_irqrestore(&priv->lock, flags);
733 return mct_u232_set_modem_ctrl(port, control_state);
734}
735
736static void mct_u232_throttle(struct tty_struct *tty)
737{
738 struct usb_serial_port *port = tty->driver_data;
739 struct mct_u232_private *priv = usb_get_serial_port_data(port);
740 unsigned int control_state;
741
742 spin_lock_irq(&priv->lock);
743 priv->rx_flags |= THROTTLED;
744 if (C_CRTSCTS(tty)) {
745 priv->control_state &= ~TIOCM_RTS;
746 control_state = priv->control_state;
747 spin_unlock_irq(&priv->lock);
748 mct_u232_set_modem_ctrl(port, control_state);
749 } else {
750 spin_unlock_irq(&priv->lock);
751 }
752}
753
754static void mct_u232_unthrottle(struct tty_struct *tty)
755{
756 struct usb_serial_port *port = tty->driver_data;
757 struct mct_u232_private *priv = usb_get_serial_port_data(port);
758 unsigned int control_state;
759
760 spin_lock_irq(&priv->lock);
761 if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
762 priv->rx_flags &= ~THROTTLED;
763 priv->control_state |= TIOCM_RTS;
764 control_state = priv->control_state;
765 spin_unlock_irq(&priv->lock);
766 mct_u232_set_modem_ctrl(port, control_state);
767 } else {
768 spin_unlock_irq(&priv->lock);
769 }
770}
771
772module_usb_serial_driver(serial_drivers, id_table);
773
774MODULE_AUTHOR(DRIVER_AUTHOR);
775MODULE_DESCRIPTION(DRIVER_DESC);
776MODULE_LICENSE("GPL");