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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 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");
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");