2 * MCT (Magic Control Technology Corp.) USB RS232 Converter Driver
4 * Copyright (C) 2000 Wolfgang Grandegger (wolfgang@ces.ch)
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is largely derived from the Belkin USB Serial Adapter Driver
12 * (see belkin_sa.[ch]). All of the information about the device was acquired
13 * by using SniffUSB on Windows98. For technical details see mct_u232.h.
15 * William G. Greathouse and Greg Kroah-Hartman provided great help on how to
16 * do the reverse engineering and how to write a USB serial device driver.
18 * TO BE DONE, TO BE CHECKED:
19 * DTR/RTS signal handling may be incomplete or incorrect. I have mainly
20 * implemented what I have seen with SniffUSB or found in belkin_sa.c.
21 * For further TODOs check also belkin_sa.c.
24 * Basic tests have been performed with minicom/zmodem transfers and
25 * modem dialing under Linux 2.4.0-test10 (for me it works fine).
27 * 04-Nov-2003 Bill Marr <marr at flex dot com>
28 * - Mimic Windows driver by sending 2 USB 'device request' messages
29 * following normal 'baud rate change' message. This allows data to be
30 * transmitted to RS-232 devices which don't assert the 'CTS' signal.
32 * 10-Nov-2001 Wolfgang Grandegger
33 * - Fixed an endianess problem with the baudrate selection for PowerPC.
35 * 06-Dec-2001 Martin Hamilton <martinh@gnu.org>
36 * - Added support for the Belkin F5U109 DB9 adaptor
38 * 30-May-2001 Greg Kroah-Hartman
39 * - switched from using spinlock to a semaphore, which fixes lots of
42 * 04-May-2001 Stelian Pop
43 * - Set the maximum bulk output size for Sitecom U232-P25 model to 16 bytes
44 * instead of the device reported 32 (using 32 bytes causes many data
45 * loss, Windows driver uses 16 too).
47 * 02-May-2001 Stelian Pop
48 * - Fixed the baud calculation for Sitecom U232-P25 model
51 * - Identify version on module load.
53 * 06-Jan-2001 Cornel Ciocirlan
54 * - Added support for Sitecom U232-P25 model (Product Id 0x0230)
55 * - Added support for D-Link DU-H3SP USB BAY (Product Id 0x0200)
57 * 29-Nov-2000 Greg Kroah-Hartman
58 * - Added device id table to fit with 2.4.0-test11 structure.
59 * - took out DEAL_WITH_TWO_INT_IN_ENDPOINTS #define as it's not needed
60 * (lots of things will change if/when the usb-serial core changes to
61 * handle these issues.
63 * 27-Nov-2000 Wolfgang Grandegge
64 * A version for kernel 2.4.0-test10 released to the Linux community
65 * (via linux-usb-devel).
68 #include <linux/kernel.h>
69 #include <linux/errno.h>
70 #include <linux/init.h>
71 #include <linux/slab.h>
72 #include <linux/tty.h>
73 #include <linux/tty_driver.h>
74 #include <linux/tty_flip.h>
75 #include <linux/module.h>
76 #include <linux/spinlock.h>
77 #include <linux/uaccess.h>
78 #include <linux/usb.h>
79 #include <linux/usb/serial.h>
85 #define DRIVER_VERSION "z2.1" /* Linux in-kernel version */
86 #define DRIVER_AUTHOR "Wolfgang Grandegger <wolfgang@ces.ch>"
87 #define DRIVER_DESC "Magic Control Technology USB-RS232 converter driver"
94 static int mct_u232_startup(struct usb_serial *serial);
95 static void mct_u232_shutdown(struct usb_serial *serial);
96 static int mct_u232_open(struct tty_struct *tty,
97 struct usb_serial_port *port, struct file *filp);
98 static void mct_u232_close(struct tty_struct *tty,
99 struct usb_serial_port *port, struct file *filp);
100 static void mct_u232_read_int_callback(struct urb *urb);
101 static void mct_u232_set_termios(struct tty_struct *tty,
102 struct usb_serial_port *port, struct ktermios *old);
103 static void mct_u232_break_ctl(struct tty_struct *tty, int break_state);
104 static int mct_u232_tiocmget(struct tty_struct *tty, struct file *file);
105 static int mct_u232_tiocmset(struct tty_struct *tty, struct file *file,
106 unsigned int set, unsigned int clear);
107 static void mct_u232_throttle(struct tty_struct *tty);
108 static void mct_u232_unthrottle(struct tty_struct *tty);
112 * All of the device info needed for the MCT USB-RS232 converter.
114 static struct usb_device_id id_table_combined [] = {
115 { USB_DEVICE(MCT_U232_VID, MCT_U232_PID) },
116 { USB_DEVICE(MCT_U232_VID, MCT_U232_SITECOM_PID) },
117 { USB_DEVICE(MCT_U232_VID, MCT_U232_DU_H3SP_PID) },
118 { USB_DEVICE(MCT_U232_BELKIN_F5U109_VID, MCT_U232_BELKIN_F5U109_PID) },
119 { } /* Terminating entry */
122 MODULE_DEVICE_TABLE(usb, id_table_combined);
124 static struct usb_driver mct_u232_driver = {
126 .probe = usb_serial_probe,
127 .disconnect = usb_serial_disconnect,
128 .id_table = id_table_combined,
132 static struct usb_serial_driver mct_u232_device = {
134 .owner = THIS_MODULE,
137 .description = "MCT U232",
138 .usb_driver = &mct_u232_driver,
139 .id_table = id_table_combined,
141 .open = mct_u232_open,
142 .close = mct_u232_close,
143 .throttle = mct_u232_throttle,
144 .unthrottle = mct_u232_unthrottle,
145 .read_int_callback = mct_u232_read_int_callback,
146 .set_termios = mct_u232_set_termios,
147 .break_ctl = mct_u232_break_ctl,
148 .tiocmget = mct_u232_tiocmget,
149 .tiocmset = mct_u232_tiocmset,
150 .attach = mct_u232_startup,
151 .shutdown = mct_u232_shutdown,
155 struct mct_u232_private {
157 unsigned int control_state; /* Modem Line Setting (TIOCM) */
158 unsigned char last_lcr; /* Line Control Register */
159 unsigned char last_lsr; /* Line Status Register */
160 unsigned char last_msr; /* Modem Status Register */
161 unsigned int rx_flags; /* Throttling flags */
164 #define THROTTLED 0x01
167 * Handle vendor specific USB requests
170 #define WDR_TIMEOUT 5000 /* default urb timeout */
173 * Later day 2.6.0-test kernels have new baud rates like B230400 which
174 * we do not know how to support. We ignore them for the moment.
176 static int mct_u232_calculate_baud_rate(struct usb_serial *serial,
177 speed_t value, speed_t *result)
181 if (le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_SITECOM_PID
182 || le16_to_cpu(serial->dev->descriptor.idProduct) == MCT_U232_BELKIN_F5U109_PID) {
187 return 0x02; /* this one not tested */
209 /* FIXME: Can we use any divider - should we do
210 divider = 115200/value;
211 real baud = 115200/divider */
231 static int mct_u232_set_baud_rate(struct tty_struct *tty,
232 struct usb_serial *serial, struct usb_serial_port *port, speed_t value)
236 unsigned char zero_byte = 0;
237 unsigned char cts_enable_byte = 0;
240 divisor = cpu_to_le32(mct_u232_calculate_baud_rate(serial, value,
243 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
244 MCT_U232_SET_BAUD_RATE_REQUEST,
245 MCT_U232_SET_REQUEST_TYPE,
246 0, 0, &divisor, MCT_U232_SET_BAUD_RATE_SIZE,
248 if (rc < 0) /*FIXME: What value speed results */
249 err("Set BAUD RATE %d failed (error = %d)", value, rc);
251 tty_encode_baud_rate(tty, speed, speed);
252 dbg("set_baud_rate: value: 0x%x, divisor: 0x%x", value, divisor);
254 /* Mimic the MCT-supplied Windows driver (version 1.21P.0104), which
255 always sends two extra USB 'device request' messages after the
256 'baud rate change' message. The actual functionality of the
257 request codes in these messages is not fully understood but these
258 particular codes are never seen in any operation besides a baud
259 rate change. Both of these messages send a single byte of data.
260 In the first message, the value of this byte is always zero.
262 The second message has been determined experimentally to control
263 whether data will be transmitted to a device which is not asserting
264 the 'CTS' signal. If the second message's data byte is zero, data
265 will be transmitted even if 'CTS' is not asserted (i.e. no hardware
266 flow control). if the second message's data byte is nonzero (a
267 value of 1 is used by this driver), data will not be transmitted to
268 a device which is not asserting 'CTS'.
271 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
272 MCT_U232_SET_UNKNOWN1_REQUEST,
273 MCT_U232_SET_REQUEST_TYPE,
274 0, 0, &zero_byte, MCT_U232_SET_UNKNOWN1_SIZE,
277 err("Sending USB device request code %d failed (error = %d)",
278 MCT_U232_SET_UNKNOWN1_REQUEST, rc);
280 if (port && C_CRTSCTS(tty))
283 dbg("set_baud_rate: send second control message, data = %02X",
285 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
286 MCT_U232_SET_CTS_REQUEST,
287 MCT_U232_SET_REQUEST_TYPE,
288 0, 0, &cts_enable_byte, MCT_U232_SET_CTS_SIZE,
291 err("Sending USB device request code %d failed (error = %d)",
292 MCT_U232_SET_CTS_REQUEST, rc);
295 } /* mct_u232_set_baud_rate */
297 static int mct_u232_set_line_ctrl(struct usb_serial *serial, unsigned char lcr)
300 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
301 MCT_U232_SET_LINE_CTRL_REQUEST,
302 MCT_U232_SET_REQUEST_TYPE,
303 0, 0, &lcr, MCT_U232_SET_LINE_CTRL_SIZE,
306 err("Set LINE CTRL 0x%x failed (error = %d)", lcr, rc);
307 dbg("set_line_ctrl: 0x%x", lcr);
309 } /* mct_u232_set_line_ctrl */
311 static int mct_u232_set_modem_ctrl(struct usb_serial *serial,
312 unsigned int control_state)
315 unsigned char mcr = MCT_U232_MCR_NONE;
317 if (control_state & TIOCM_DTR)
318 mcr |= MCT_U232_MCR_DTR;
319 if (control_state & TIOCM_RTS)
320 mcr |= MCT_U232_MCR_RTS;
322 rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
323 MCT_U232_SET_MODEM_CTRL_REQUEST,
324 MCT_U232_SET_REQUEST_TYPE,
325 0, 0, &mcr, MCT_U232_SET_MODEM_CTRL_SIZE,
328 err("Set MODEM CTRL 0x%x failed (error = %d)", mcr, rc);
329 dbg("set_modem_ctrl: state=0x%x ==> mcr=0x%x", control_state, mcr);
332 } /* mct_u232_set_modem_ctrl */
334 static int mct_u232_get_modem_stat(struct usb_serial *serial,
338 rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
339 MCT_U232_GET_MODEM_STAT_REQUEST,
340 MCT_U232_GET_REQUEST_TYPE,
341 0, 0, msr, MCT_U232_GET_MODEM_STAT_SIZE,
344 err("Get MODEM STATus failed (error = %d)", rc);
347 dbg("get_modem_stat: 0x%x", *msr);
349 } /* mct_u232_get_modem_stat */
351 static void mct_u232_msr_to_state(unsigned int *control_state,
354 /* Translate Control Line states */
355 if (msr & MCT_U232_MSR_DSR)
356 *control_state |= TIOCM_DSR;
358 *control_state &= ~TIOCM_DSR;
359 if (msr & MCT_U232_MSR_CTS)
360 *control_state |= TIOCM_CTS;
362 *control_state &= ~TIOCM_CTS;
363 if (msr & MCT_U232_MSR_RI)
364 *control_state |= TIOCM_RI;
366 *control_state &= ~TIOCM_RI;
367 if (msr & MCT_U232_MSR_CD)
368 *control_state |= TIOCM_CD;
370 *control_state &= ~TIOCM_CD;
371 dbg("msr_to_state: msr=0x%x ==> state=0x%x", msr, *control_state);
372 } /* mct_u232_msr_to_state */
375 * Driver's tty interface functions
378 static int mct_u232_startup(struct usb_serial *serial)
380 struct mct_u232_private *priv;
381 struct usb_serial_port *port, *rport;
383 priv = kzalloc(sizeof(struct mct_u232_private), GFP_KERNEL);
386 spin_lock_init(&priv->lock);
387 usb_set_serial_port_data(serial->port[0], priv);
389 init_waitqueue_head(&serial->port[0]->write_wait);
391 /* Puh, that's dirty */
392 port = serial->port[0];
393 rport = serial->port[1];
394 /* No unlinking, it wasn't submitted yet. */
395 usb_free_urb(port->read_urb);
396 port->read_urb = rport->interrupt_in_urb;
397 rport->interrupt_in_urb = NULL;
398 port->read_urb->context = port;
401 } /* mct_u232_startup */
404 static void mct_u232_shutdown(struct usb_serial *serial)
406 struct mct_u232_private *priv;
411 for (i = 0; i < serial->num_ports; ++i) {
412 /* My special items, the standard routines free my urbs */
413 priv = usb_get_serial_port_data(serial->port[i]);
415 usb_set_serial_port_data(serial->port[i], NULL);
419 } /* mct_u232_shutdown */
421 static int mct_u232_open(struct tty_struct *tty,
422 struct usb_serial_port *port, struct file *filp)
424 struct usb_serial *serial = port->serial;
425 struct mct_u232_private *priv = usb_get_serial_port_data(port);
427 unsigned int control_state;
429 unsigned char last_lcr;
430 unsigned char last_msr;
432 dbg("%s port %d", __func__, port->number);
434 /* Compensate for a hardware bug: although the Sitecom U232-P25
435 * device reports a maximum output packet size of 32 bytes,
436 * it seems to be able to accept only 16 bytes (and that's what
437 * SniffUSB says too...)
439 if (le16_to_cpu(serial->dev->descriptor.idProduct)
440 == MCT_U232_SITECOM_PID)
441 port->bulk_out_size = 16;
443 /* Do a defined restart: the normal serial device seems to
444 * always turn on DTR and RTS here, so do the same. I'm not
445 * sure if this is really necessary. But it should not harm
448 spin_lock_irqsave(&priv->lock, flags);
449 if (tty && (tty->termios->c_cflag & CBAUD))
450 priv->control_state = TIOCM_DTR | TIOCM_RTS;
452 priv->control_state = 0;
454 priv->last_lcr = (MCT_U232_DATA_BITS_8 |
455 MCT_U232_PARITY_NONE |
456 MCT_U232_STOP_BITS_1);
457 control_state = priv->control_state;
458 last_lcr = priv->last_lcr;
459 spin_unlock_irqrestore(&priv->lock, flags);
460 mct_u232_set_modem_ctrl(serial, control_state);
461 mct_u232_set_line_ctrl(serial, last_lcr);
463 /* Read modem status and update control state */
464 mct_u232_get_modem_stat(serial, &last_msr);
465 spin_lock_irqsave(&priv->lock, flags);
466 priv->last_msr = last_msr;
467 mct_u232_msr_to_state(&priv->control_state, priv->last_msr);
468 spin_unlock_irqrestore(&priv->lock, flags);
470 port->read_urb->dev = port->serial->dev;
471 retval = usb_submit_urb(port->read_urb, GFP_KERNEL);
473 err("usb_submit_urb(read bulk) failed pipe 0x%x err %d",
474 port->read_urb->pipe, retval);
478 port->interrupt_in_urb->dev = port->serial->dev;
479 retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
481 usb_kill_urb(port->read_urb);
482 err(" usb_submit_urb(read int) failed pipe 0x%x err %d",
483 port->interrupt_in_urb->pipe, retval);
490 } /* mct_u232_open */
493 static void mct_u232_close(struct tty_struct *tty,
494 struct usb_serial_port *port, struct file *filp)
496 unsigned int c_cflag;
497 unsigned int control_state;
498 struct mct_u232_private *priv = usb_get_serial_port_data(port);
499 dbg("%s port %d", __func__, port->number);
502 c_cflag = tty->termios->c_cflag;
503 mutex_lock(&port->serial->disc_mutex);
504 if (c_cflag & HUPCL && !port->serial->disconnected) {
505 /* drop DTR and RTS */
506 spin_lock_irq(&priv->lock);
507 priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
508 control_state = priv->control_state;
509 spin_unlock_irq(&priv->lock);
510 mct_u232_set_modem_ctrl(port->serial, control_state);
512 mutex_unlock(&port->serial->disc_mutex);
516 if (port->serial->dev) {
517 /* shutdown our urbs */
518 usb_kill_urb(port->write_urb);
519 usb_kill_urb(port->read_urb);
520 usb_kill_urb(port->interrupt_in_urb);
522 } /* mct_u232_close */
525 static void mct_u232_read_int_callback(struct urb *urb)
527 struct usb_serial_port *port = urb->context;
528 struct mct_u232_private *priv = usb_get_serial_port_data(port);
529 struct usb_serial *serial = port->serial;
530 struct tty_struct *tty;
531 unsigned char *data = urb->transfer_buffer;
533 int status = urb->status;
543 /* this urb is terminated, clean up */
544 dbg("%s - urb shutting down with status: %d",
548 dbg("%s - nonzero urb status received: %d",
554 dbg("%s - bad serial pointer, exiting", __func__);
558 dbg("%s - port %d", __func__, port->number);
559 usb_serial_debug_data(debug, &port->dev, __func__,
560 urb->actual_length, data);
563 * Work-a-round: handle the 'usual' bulk-in pipe here
565 if (urb->transfer_buffer_length > 2) {
566 tty = tty_port_tty_get(&port->port);
567 if (urb->actual_length) {
568 tty_insert_flip_string(tty, data, urb->actual_length);
569 tty_flip_buffer_push(tty);
576 * The interrupt-in pipe signals exceptional conditions (modem line
577 * signal changes and errors). data[0] holds MSR, data[1] holds LSR.
579 spin_lock_irqsave(&priv->lock, flags);
580 priv->last_msr = data[MCT_U232_MSR_INDEX];
582 /* Record Control Line states */
583 mct_u232_msr_to_state(&priv->control_state, priv->last_msr);
586 /* Not yet handled. See belkin_sa.c for further information */
587 /* Now to report any errors */
588 priv->last_lsr = data[MCT_U232_LSR_INDEX];
590 * fill in the flip buffer here, but I do not know the relation
591 * to the current/next receive buffer or characters. I need
592 * to look in to this before committing any code.
594 if (priv->last_lsr & MCT_U232_LSR_ERR) {
595 tty = tty_port_tty_get(&port->port);
597 if (priv->last_lsr & MCT_U232_LSR_OE) {
600 if (priv->last_lsr & MCT_U232_LSR_PE) {
603 if (priv->last_lsr & MCT_U232_LSR_FE) {
605 /* Break Indicator */
606 if (priv->last_lsr & MCT_U232_LSR_BI) {
611 spin_unlock_irqrestore(&priv->lock, flags);
613 retval = usb_submit_urb(urb, GFP_ATOMIC);
615 err("%s - usb_submit_urb failed with result %d",
617 } /* mct_u232_read_int_callback */
619 static void mct_u232_set_termios(struct tty_struct *tty,
620 struct usb_serial_port *port,
621 struct ktermios *old_termios)
623 struct usb_serial *serial = port->serial;
624 struct mct_u232_private *priv = usb_get_serial_port_data(port);
625 struct ktermios *termios = tty->termios;
626 unsigned int cflag = termios->c_cflag;
627 unsigned int old_cflag = old_termios->c_cflag;
629 unsigned int control_state;
630 unsigned char last_lcr;
632 /* get a local copy of the current port settings */
633 spin_lock_irqsave(&priv->lock, flags);
634 control_state = priv->control_state;
635 spin_unlock_irqrestore(&priv->lock, flags);
640 * Do not attempt to cache old rates and skip settings,
641 * disconnects screw such tricks up completely.
642 * Premature optimization is the root of all evil.
645 /* reassert DTR and RTS on transition from B0 */
646 if ((old_cflag & CBAUD) == B0) {
647 dbg("%s: baud was B0", __func__);
648 control_state |= TIOCM_DTR | TIOCM_RTS;
649 mct_u232_set_modem_ctrl(serial, control_state);
652 mct_u232_set_baud_rate(tty, serial, port, tty_get_baud_rate(tty));
654 if ((cflag & CBAUD) == B0) {
655 dbg("%s: baud is B0", __func__);
656 /* Drop RTS and DTR */
657 control_state &= ~(TIOCM_DTR | TIOCM_RTS);
658 mct_u232_set_modem_ctrl(serial, control_state);
662 * Update line control register (LCR)
667 last_lcr |= (cflag & PARODD) ?
668 MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
670 last_lcr |= MCT_U232_PARITY_NONE;
672 /* set the number of data bits */
673 switch (cflag & CSIZE) {
675 last_lcr |= MCT_U232_DATA_BITS_5; break;
677 last_lcr |= MCT_U232_DATA_BITS_6; break;
679 last_lcr |= MCT_U232_DATA_BITS_7; break;
681 last_lcr |= MCT_U232_DATA_BITS_8; break;
683 err("CSIZE was not CS5-CS8, using default of 8");
684 last_lcr |= MCT_U232_DATA_BITS_8;
688 termios->c_cflag &= ~CMSPAR;
690 /* set the number of stop bits */
691 last_lcr |= (cflag & CSTOPB) ?
692 MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
694 mct_u232_set_line_ctrl(serial, last_lcr);
696 /* save off the modified port settings */
697 spin_lock_irqsave(&priv->lock, flags);
698 priv->control_state = control_state;
699 priv->last_lcr = last_lcr;
700 spin_unlock_irqrestore(&priv->lock, flags);
701 } /* mct_u232_set_termios */
703 static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
705 struct usb_serial_port *port = tty->driver_data;
706 struct usb_serial *serial = port->serial;
707 struct mct_u232_private *priv = usb_get_serial_port_data(port);
711 dbg("%sstate=%d", __func__, break_state);
713 spin_lock_irqsave(&priv->lock, flags);
714 lcr = priv->last_lcr;
715 spin_unlock_irqrestore(&priv->lock, flags);
718 lcr |= MCT_U232_SET_BREAK;
720 mct_u232_set_line_ctrl(serial, lcr);
721 } /* mct_u232_break_ctl */
724 static int mct_u232_tiocmget(struct tty_struct *tty, struct file *file)
726 struct usb_serial_port *port = tty->driver_data;
727 struct mct_u232_private *priv = usb_get_serial_port_data(port);
728 unsigned int control_state;
733 spin_lock_irqsave(&priv->lock, flags);
734 control_state = priv->control_state;
735 spin_unlock_irqrestore(&priv->lock, flags);
737 return control_state;
740 static int mct_u232_tiocmset(struct tty_struct *tty, struct file *file,
741 unsigned int set, unsigned int clear)
743 struct usb_serial_port *port = tty->driver_data;
744 struct usb_serial *serial = port->serial;
745 struct mct_u232_private *priv = usb_get_serial_port_data(port);
746 unsigned int control_state;
751 spin_lock_irqsave(&priv->lock, flags);
752 control_state = priv->control_state;
755 control_state |= TIOCM_RTS;
757 control_state |= TIOCM_DTR;
758 if (clear & TIOCM_RTS)
759 control_state &= ~TIOCM_RTS;
760 if (clear & TIOCM_DTR)
761 control_state &= ~TIOCM_DTR;
763 priv->control_state = control_state;
764 spin_unlock_irqrestore(&priv->lock, flags);
765 return mct_u232_set_modem_ctrl(serial, control_state);
768 static void mct_u232_throttle(struct tty_struct *tty)
770 struct usb_serial_port *port = tty->driver_data;
771 struct mct_u232_private *priv = usb_get_serial_port_data(port);
773 unsigned int control_state;
775 dbg("%s - port %d", __func__, port->number);
777 spin_lock_irqsave(&priv->lock, flags);
778 priv->rx_flags |= THROTTLED;
779 if (C_CRTSCTS(tty)) {
780 priv->control_state &= ~TIOCM_RTS;
781 control_state = priv->control_state;
782 spin_unlock_irqrestore(&priv->lock, flags);
783 (void) mct_u232_set_modem_ctrl(port->serial, control_state);
785 spin_unlock_irqrestore(&priv->lock, flags);
790 static void mct_u232_unthrottle(struct tty_struct *tty)
792 struct usb_serial_port *port = tty->driver_data;
793 struct mct_u232_private *priv = usb_get_serial_port_data(port);
795 unsigned int control_state;
797 dbg("%s - port %d", __func__, port->number);
799 spin_lock_irqsave(&priv->lock, flags);
800 if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) {
801 priv->rx_flags &= ~THROTTLED;
802 priv->control_state |= TIOCM_RTS;
803 control_state = priv->control_state;
804 spin_unlock_irqrestore(&priv->lock, flags);
805 (void) mct_u232_set_modem_ctrl(port->serial, control_state);
807 spin_unlock_irqrestore(&priv->lock, flags);
811 static int __init mct_u232_init(void)
814 retval = usb_serial_register(&mct_u232_device);
816 goto failed_usb_serial_register;
817 retval = usb_register(&mct_u232_driver);
819 goto failed_usb_register;
820 info(DRIVER_DESC " " DRIVER_VERSION);
823 usb_serial_deregister(&mct_u232_device);
824 failed_usb_serial_register:
829 static void __exit mct_u232_exit(void)
831 usb_deregister(&mct_u232_driver);
832 usb_serial_deregister(&mct_u232_device);
835 module_init(mct_u232_init);
836 module_exit(mct_u232_exit);
838 MODULE_AUTHOR(DRIVER_AUTHOR);
839 MODULE_DESCRIPTION(DRIVER_DESC);
840 MODULE_LICENSE("GPL");
842 module_param(debug, bool, S_IRUGO | S_IWUSR);
843 MODULE_PARM_DESC(debug, "Debug enabled or not");