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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 <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 int 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, struct ktermios *old);
49static void mct_u232_break_ctl(struct tty_struct *tty, int break_state);
50static int mct_u232_tiocmget(struct tty_struct *tty);
51static int mct_u232_tiocmset(struct tty_struct *tty,
52 unsigned int set, unsigned int clear);
53static void mct_u232_throttle(struct tty_struct *tty);
54static void mct_u232_unthrottle(struct tty_struct *tty);
55
56
57/*
58 * All of the device info needed for the MCT USB-RS232 converter.
59 */
60static const struct usb_device_id id_table[] = {
61 { USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
62 { USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
63 { USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
64 { USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
65 { } /* Terminating entry */
66};
67MODULE_DEVICE_TABLE(usb, id_table);
68
69static struct usb_serial_driver mct_u232_device = {
70 .driver = {
71 .owner = THIS_MODULE,
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 int 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 return 0;
411}
412
413static int mct_u232_open(struct tty_struct *tty, struct usb_serial_port *port)
414{
415 struct usb_serial *serial = port->serial;
416 struct mct_u232_private *priv = usb_get_serial_port_data(port);
417 int retval = 0;
418 unsigned int control_state;
419 unsigned long flags;
420 unsigned char last_lcr;
421 unsigned char last_msr;
422
423 /* Compensate for a hardware bug: although the Sitecom U232-P25
424 * device reports a maximum output packet size of 32 bytes,
425 * it seems to be able to accept only 16 bytes (and that's what
426 * SniffUSB says too...)
427 */
428 if (le16_to_cpu(serial->dev->descriptor.idProduct)
429 == MCT_U232_SITECOM_PID)
430 port->bulk_out_size = 16;
431
432 /* Do a defined restart: the normal serial device seems to
433 * always turn on DTR and RTS here, so do the same. I'm not
434 * sure if this is really necessary. But it should not harm
435 * either.
436 */
437 spin_lock_irqsave(&priv->lock, flags);
438 if (tty && C_BAUD(tty))
439 priv->control_state = TIOCM_DTR | TIOCM_RTS;
440 else
441 priv->control_state = 0;
442
443 priv->last_lcr = (MCT_U232_DATA_BITS_8 |
444 MCT_U232_PARITY_NONE |
445 MCT_U232_STOP_BITS_1);
446 control_state = priv->control_state;
447 last_lcr = priv->last_lcr;
448 spin_unlock_irqrestore(&priv->lock, flags);
449 mct_u232_set_modem_ctrl(port, control_state);
450 mct_u232_set_line_ctrl(port, last_lcr);
451
452 /* Read modem status and update control state */
453 mct_u232_get_modem_stat(port, &last_msr);
454 spin_lock_irqsave(&priv->lock, flags);
455 priv->last_msr = last_msr;
456 mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
457 spin_unlock_irqrestore(&priv->lock, flags);
458
459 retval = usb_submit_urb(priv->read_urb, GFP_KERNEL);
460 if (retval) {
461 dev_err(&port->dev,
462 "usb_submit_urb(read) failed pipe 0x%x err %d\n",
463 port->read_urb->pipe, retval);
464 goto error;
465 }
466
467 retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
468 if (retval) {
469 usb_kill_urb(priv->read_urb);
470 dev_err(&port->dev,
471 "usb_submit_urb(read int) failed pipe 0x%x err %d",
472 port->interrupt_in_urb->pipe, retval);
473 goto error;
474 }
475 return 0;
476
477error:
478 return retval;
479} /* mct_u232_open */
480
481static void mct_u232_dtr_rts(struct usb_serial_port *port, int on)
482{
483 unsigned int control_state;
484 struct mct_u232_private *priv = usb_get_serial_port_data(port);
485
486 spin_lock_irq(&priv->lock);
487 if (on)
488 priv->control_state |= TIOCM_DTR | TIOCM_RTS;
489 else
490 priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
491 control_state = priv->control_state;
492 spin_unlock_irq(&priv->lock);
493
494 mct_u232_set_modem_ctrl(port, control_state);
495}
496
497static void mct_u232_close(struct usb_serial_port *port)
498{
499 struct mct_u232_private *priv = usb_get_serial_port_data(port);
500
501 usb_kill_urb(priv->read_urb);
502 usb_kill_urb(port->interrupt_in_urb);
503
504 usb_serial_generic_close(port);
505} /* mct_u232_close */
506
507
508static void mct_u232_read_int_callback(struct urb *urb)
509{
510 struct usb_serial_port *port = urb->context;
511 struct mct_u232_private *priv = usb_get_serial_port_data(port);
512 unsigned char *data = urb->transfer_buffer;
513 int retval;
514 int status = urb->status;
515 unsigned long flags;
516
517 switch (status) {
518 case 0:
519 /* success */
520 break;
521 case -ECONNRESET:
522 case -ENOENT:
523 case -ESHUTDOWN:
524 /* this urb is terminated, clean up */
525 dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
526 __func__, status);
527 return;
528 default:
529 dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
530 __func__, status);
531 goto exit;
532 }
533
534 usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data);
535
536 /*
537 * Work-a-round: handle the 'usual' bulk-in pipe here
538 */
539 if (urb->transfer_buffer_length > 2) {
540 if (urb->actual_length) {
541 tty_insert_flip_string(&port->port, data,
542 urb->actual_length);
543 tty_flip_buffer_push(&port->port);
544 }
545 goto exit;
546 }
547
548 /*
549 * The interrupt-in pipe signals exceptional conditions (modem line
550 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
551 */
552 spin_lock_irqsave(&priv->lock, flags);
553 priv->last_msr = data[MCT_U232_MSR_INDEX];
554
555 /* Record Control Line states */
556 mct_u232_msr_to_state(port, &priv->control_state, priv->last_msr);
557
558 mct_u232_msr_to_icount(&port->icount, priv->last_msr);
559
560#if 0
561 /* Not yet handled. See belkin_sa.c for further information */
562 /* Now to report any errors */
563 priv->last_lsr = data[MCT_U232_LSR_INDEX];
564 /*
565 * fill in the flip buffer here, but I do not know the relation
566 * to the current/next receive buffer or characters. I need
567 * to look in to this before committing any code.
568 */
569 if (priv->last_lsr & MCT_U232_LSR_ERR) {
570 tty = tty_port_tty_get(&port->port);
571 /* Overrun Error */
572 if (priv->last_lsr & MCT_U232_LSR_OE) {
573 }
574 /* Parity Error */
575 if (priv->last_lsr & MCT_U232_LSR_PE) {
576 }
577 /* Framing Error */
578 if (priv->last_lsr & MCT_U232_LSR_FE) {
579 }
580 /* Break Indicator */
581 if (priv->last_lsr & MCT_U232_LSR_BI) {
582 }
583 tty_kref_put(tty);
584 }
585#endif
586 wake_up_interruptible(&port->port.delta_msr_wait);
587 spin_unlock_irqrestore(&priv->lock, flags);
588exit:
589 retval = usb_submit_urb(urb, GFP_ATOMIC);
590 if (retval)
591 dev_err(&port->dev,
592 "%s - usb_submit_urb failed with result %d\n",
593 __func__, retval);
594} /* mct_u232_read_int_callback */
595
596static void mct_u232_set_termios(struct tty_struct *tty,
597 struct usb_serial_port *port,
598 struct ktermios *old_termios)
599{
600 struct usb_serial *serial = port->serial;
601 struct mct_u232_private *priv = usb_get_serial_port_data(port);
602 struct ktermios *termios = &tty->termios;
603 unsigned int cflag = termios->c_cflag;
604 unsigned int old_cflag = old_termios->c_cflag;
605 unsigned long flags;
606 unsigned int control_state;
607 unsigned char last_lcr;
608
609 /* get a local copy of the current port settings */
610 spin_lock_irqsave(&priv->lock, flags);
611 control_state = priv->control_state;
612 spin_unlock_irqrestore(&priv->lock, flags);
613 last_lcr = 0;
614
615 /*
616 * Update baud rate.
617 * Do not attempt to cache old rates and skip settings,
618 * disconnects screw such tricks up completely.
619 * Premature optimization is the root of all evil.
620 */
621
622 /* reassert DTR and RTS on transition from B0 */
623 if ((old_cflag & CBAUD) == B0) {
624 dev_dbg(&port->dev, "%s: baud was B0\n", __func__);
625 control_state |= TIOCM_DTR | TIOCM_RTS;
626 mct_u232_set_modem_ctrl(port, control_state);
627 }
628
629 mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
630
631 if ((cflag & CBAUD) == B0) {
632 dev_dbg(&port->dev, "%s: baud is B0\n", __func__);
633 /* Drop RTS and DTR */
634 control_state &= ~(TIOCM_DTR | TIOCM_RTS);
635 mct_u232_set_modem_ctrl(port, control_state);
636 }
637
638 /*
639 * Update line control register (LCR)
640 */
641
642 /* set the parity */
643 if (cflag & PARENB)
644 last_lcr |= (cflag & PARODD) ?
645 MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
646 else
647 last_lcr |= MCT_U232_PARITY_NONE;
648
649 /* set the number of data bits */
650 switch (cflag & CSIZE) {
651 case CS5:
652 last_lcr |= MCT_U232_DATA_BITS_5; break;
653 case CS6:
654 last_lcr |= MCT_U232_DATA_BITS_6; break;
655 case CS7:
656 last_lcr |= MCT_U232_DATA_BITS_7; break;
657 case CS8:
658 last_lcr |= MCT_U232_DATA_BITS_8; break;
659 default:
660 dev_err(&port->dev,
661 "CSIZE was not CS5-CS8, using default of 8\n");
662 last_lcr |= MCT_U232_DATA_BITS_8;
663 break;
664 }
665
666 termios->c_cflag &= ~CMSPAR;
667
668 /* set the number of stop bits */
669 last_lcr |= (cflag & CSTOPB) ?
670 MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
671
672 mct_u232_set_line_ctrl(port, last_lcr);
673
674 /* save off the modified port settings */
675 spin_lock_irqsave(&priv->lock, flags);
676 priv->control_state = control_state;
677 priv->last_lcr = last_lcr;
678 spin_unlock_irqrestore(&priv->lock, flags);
679} /* mct_u232_set_termios */
680
681static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
682{
683 struct usb_serial_port *port = tty->driver_data;
684 struct mct_u232_private *priv = usb_get_serial_port_data(port);
685 unsigned char lcr;
686 unsigned long flags;
687
688 spin_lock_irqsave(&priv->lock, flags);
689 lcr = priv->last_lcr;
690
691 if (break_state)
692 lcr |= MCT_U232_SET_BREAK;
693 spin_unlock_irqrestore(&priv->lock, flags);
694
695 mct_u232_set_line_ctrl(port, lcr);
696} /* mct_u232_break_ctl */
697
698
699static int mct_u232_tiocmget(struct tty_struct *tty)
700{
701 struct usb_serial_port *port = tty->driver_data;
702 struct mct_u232_private *priv = usb_get_serial_port_data(port);
703 unsigned int control_state;
704 unsigned long flags;
705
706 spin_lock_irqsave(&priv->lock, flags);
707 control_state = priv->control_state;
708 spin_unlock_irqrestore(&priv->lock, flags);
709
710 return control_state;
711}
712
713static int mct_u232_tiocmset(struct tty_struct *tty,
714 unsigned int set, unsigned int clear)
715{
716 struct usb_serial_port *port = tty->driver_data;
717 struct mct_u232_private *priv = usb_get_serial_port_data(port);
718 unsigned int control_state;
719 unsigned long flags;
720
721 spin_lock_irqsave(&priv->lock, flags);
722 control_state = priv->control_state;
723
724 if (set & TIOCM_RTS)
725 control_state |= TIOCM_RTS;
726 if (set & TIOCM_DTR)
727 control_state |= TIOCM_DTR;
728 if (clear & TIOCM_RTS)
729 control_state &= ~TIOCM_RTS;
730 if (clear & TIOCM_DTR)
731 control_state &= ~TIOCM_DTR;
732
733 priv->control_state = control_state;
734 spin_unlock_irqrestore(&priv->lock, flags);
735 return mct_u232_set_modem_ctrl(port, control_state);
736}
737
738static void mct_u232_throttle(struct tty_struct *tty)
739{
740 struct usb_serial_port *port = tty->driver_data;
741 struct mct_u232_private *priv = usb_get_serial_port_data(port);
742 unsigned int control_state;
743
744 spin_lock_irq(&priv->lock);
745 priv->rx_flags |= THROTTLED;
746 if (C_CRTSCTS(tty)) {
747 priv->control_state &= ~TIOCM_RTS;
748 control_state = priv->control_state;
749 spin_unlock_irq(&priv->lock);
750 mct_u232_set_modem_ctrl(port, control_state);
751 } else {
752 spin_unlock_irq(&priv->lock);
753 }
754}
755
756static void mct_u232_unthrottle(struct tty_struct *tty)
757{
758 struct usb_serial_port *port = tty->driver_data;
759 struct mct_u232_private *priv = usb_get_serial_port_data(port);
760 unsigned int control_state;
761
762 spin_lock_irq(&priv->lock);
763 if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
764 priv->rx_flags &= ~THROTTLED;
765 priv->control_state |= TIOCM_RTS;
766 control_state = priv->control_state;
767 spin_unlock_irq(&priv->lock);
768 mct_u232_set_modem_ctrl(port, control_state);
769 } else {
770 spin_unlock_irq(&priv->lock);
771 }
772}
773
774module_usb_serial_driver(serial_drivers, id_table);
775
776MODULE_AUTHOR(DRIVER_AUTHOR);
777MODULE_DESCRIPTION(DRIVER_DESC);
778MODULE_LICENSE("GPL");