xref: /openbmc/linux/drivers/usb/serial/kl5kusb105.c (revision 12eb4683)
1 /*
2  * KLSI KL5KUSB105 chip RS232 converter driver
3  *
4  *   Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
5  *   Copyright (C) 2001 Utz-Uwe Haus <haus@uuhaus.de>
6  *
7  *   This program is free software; you can redistribute it and/or modify
8  *   it under the terms of the GNU General Public License as published by
9  *   the Free Software Foundation; either version 2 of the License, or
10  *   (at your option) any later version.
11  *
12  * All information about the device was acquired using SniffUSB ans snoopUSB
13  * on Windows98.
14  * It was written out of frustration with the PalmConnect USB Serial adapter
15  * sold by Palm Inc.
16  * Neither Palm, nor their contractor (MCCI) or their supplier (KLSI) provided
17  * information that was not already available.
18  *
19  * It seems that KLSI bought some silicon-design information from ScanLogic,
20  * whose SL11R processor is at the core of the KL5KUSB chipset from KLSI.
21  * KLSI has firmware available for their devices; it is probable that the
22  * firmware differs from that used by KLSI in their products. If you have an
23  * original KLSI device and can provide some information on it, I would be
24  * most interested in adding support for it here. If you have any information
25  * on the protocol used (or find errors in my reverse-engineered stuff), please
26  * let me know.
27  *
28  * The code was only tested with a PalmConnect USB adapter; if you
29  * are adventurous, try it with any KLSI-based device and let me know how it
30  * breaks so that I can fix it!
31  */
32 
33 /* TODO:
34  *	check modem line signals
35  *	implement handshaking or decide that we do not support it
36  */
37 
38 #include <linux/kernel.h>
39 #include <linux/errno.h>
40 #include <linux/init.h>
41 #include <linux/slab.h>
42 #include <linux/tty.h>
43 #include <linux/tty_driver.h>
44 #include <linux/tty_flip.h>
45 #include <linux/module.h>
46 #include <linux/uaccess.h>
47 #include <asm/unaligned.h>
48 #include <linux/usb.h>
49 #include <linux/usb/serial.h>
50 #include "kl5kusb105.h"
51 
52 #define DRIVER_AUTHOR "Utz-Uwe Haus <haus@uuhaus.de>, Johan Hovold <jhovold@gmail.com>"
53 #define DRIVER_DESC "KLSI KL5KUSB105 chipset USB->Serial Converter driver"
54 
55 
56 /*
57  * Function prototypes
58  */
59 static int klsi_105_port_probe(struct usb_serial_port *port);
60 static int klsi_105_port_remove(struct usb_serial_port *port);
61 static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port);
62 static void klsi_105_close(struct usb_serial_port *port);
63 static void klsi_105_set_termios(struct tty_struct *tty,
64 			struct usb_serial_port *port, struct ktermios *old);
65 static int  klsi_105_tiocmget(struct tty_struct *tty);
66 static int  klsi_105_tiocmset(struct tty_struct *tty,
67 			unsigned int set, unsigned int clear);
68 static void klsi_105_process_read_urb(struct urb *urb);
69 static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
70 						void *dest, size_t size);
71 
72 /*
73  * All of the device info needed for the KLSI converters.
74  */
75 static const struct usb_device_id id_table[] = {
76 	{ USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
77 	{ USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
78 	{ }		/* Terminating entry */
79 };
80 
81 MODULE_DEVICE_TABLE(usb, id_table);
82 
83 static struct usb_serial_driver kl5kusb105d_device = {
84 	.driver = {
85 		.owner =	THIS_MODULE,
86 		.name =		"kl5kusb105d",
87 	},
88 	.description =		"KL5KUSB105D / PalmConnect",
89 	.id_table =		id_table,
90 	.num_ports =		1,
91 	.bulk_out_size =	64,
92 	.open =			klsi_105_open,
93 	.close =		klsi_105_close,
94 	.set_termios =		klsi_105_set_termios,
95 	/*.break_ctl =		klsi_105_break_ctl,*/
96 	.tiocmget =		klsi_105_tiocmget,
97 	.tiocmset =		klsi_105_tiocmset,
98 	.port_probe =		klsi_105_port_probe,
99 	.port_remove =		klsi_105_port_remove,
100 	.throttle =		usb_serial_generic_throttle,
101 	.unthrottle =		usb_serial_generic_unthrottle,
102 	.process_read_urb =	klsi_105_process_read_urb,
103 	.prepare_write_buffer =	klsi_105_prepare_write_buffer,
104 };
105 
106 static struct usb_serial_driver * const serial_drivers[] = {
107 	&kl5kusb105d_device, NULL
108 };
109 
110 struct klsi_105_port_settings {
111 	__u8	pktlen;		/* always 5, it seems */
112 	__u8	baudrate;
113 	__u8	databits;
114 	__u8	unknown1;
115 	__u8	unknown2;
116 } __attribute__ ((packed));
117 
118 struct klsi_105_private {
119 	struct klsi_105_port_settings	cfg;
120 	struct ktermios			termios;
121 	unsigned long			line_state; /* modem line settings */
122 	spinlock_t			lock;
123 };
124 
125 
126 /*
127  * Handle vendor specific USB requests
128  */
129 
130 
131 #define KLSI_TIMEOUT	 5000 /* default urb timeout */
132 
133 static int klsi_105_chg_port_settings(struct usb_serial_port *port,
134 				      struct klsi_105_port_settings *settings)
135 {
136 	int rc;
137 
138 	rc = usb_control_msg(port->serial->dev,
139 			usb_sndctrlpipe(port->serial->dev, 0),
140 			KL5KUSB105A_SIO_SET_DATA,
141 			USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
142 			0, /* value */
143 			0, /* index */
144 			settings,
145 			sizeof(struct klsi_105_port_settings),
146 			KLSI_TIMEOUT);
147 	if (rc < 0)
148 		dev_err(&port->dev,
149 			"Change port settings failed (error = %d)\n", rc);
150 	dev_info(&port->serial->dev->dev,
151 		 "%d byte block, baudrate %x, databits %d, u1 %d, u2 %d\n",
152 		 settings->pktlen, settings->baudrate, settings->databits,
153 		 settings->unknown1, settings->unknown2);
154 	return rc;
155 }
156 
157 /* translate a 16-bit status value from the device to linux's TIO bits */
158 static unsigned long klsi_105_status2linestate(const __u16 status)
159 {
160 	unsigned long res = 0;
161 
162 	res =   ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
163 	      | ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
164 	      ;
165 
166 	return res;
167 }
168 
169 /*
170  * Read line control via vendor command and return result through
171  * *line_state_p
172  */
173 /* It seems that the status buffer has always only 2 bytes length */
174 #define KLSI_STATUSBUF_LEN	2
175 static int klsi_105_get_line_state(struct usb_serial_port *port,
176 				   unsigned long *line_state_p)
177 {
178 	int rc;
179 	u8 *status_buf;
180 	__u16 status;
181 
182 	dev_info(&port->serial->dev->dev, "sending SIO Poll request\n");
183 
184 	status_buf = kmalloc(KLSI_STATUSBUF_LEN, GFP_KERNEL);
185 	if (!status_buf) {
186 		dev_err(&port->dev, "%s - out of memory for status buffer.\n",
187 				__func__);
188 		return -ENOMEM;
189 	}
190 	status_buf[0] = 0xff;
191 	status_buf[1] = 0xff;
192 	rc = usb_control_msg(port->serial->dev,
193 			     usb_rcvctrlpipe(port->serial->dev, 0),
194 			     KL5KUSB105A_SIO_POLL,
195 			     USB_TYPE_VENDOR | USB_DIR_IN,
196 			     0, /* value */
197 			     0, /* index */
198 			     status_buf, KLSI_STATUSBUF_LEN,
199 			     10000
200 			     );
201 	if (rc < 0)
202 		dev_err(&port->dev, "Reading line status failed (error = %d)\n",
203 			rc);
204 	else {
205 		status = get_unaligned_le16(status_buf);
206 
207 		dev_info(&port->serial->dev->dev, "read status %x %x",
208 			 status_buf[0], status_buf[1]);
209 
210 		*line_state_p = klsi_105_status2linestate(status);
211 	}
212 
213 	kfree(status_buf);
214 	return rc;
215 }
216 
217 
218 /*
219  * Driver's tty interface functions
220  */
221 
222 static int klsi_105_port_probe(struct usb_serial_port *port)
223 {
224 	struct klsi_105_private *priv;
225 
226 	priv = kmalloc(sizeof(*priv), GFP_KERNEL);
227 	if (!priv)
228 		return -ENOMEM;
229 
230 	/* set initial values for control structures */
231 	priv->cfg.pktlen    = 5;
232 	priv->cfg.baudrate  = kl5kusb105a_sio_b9600;
233 	priv->cfg.databits  = kl5kusb105a_dtb_8;
234 	priv->cfg.unknown1  = 0;
235 	priv->cfg.unknown2  = 1;
236 
237 	priv->line_state    = 0;
238 
239 	spin_lock_init(&priv->lock);
240 
241 	/* priv->termios is left uninitialized until port opening */
242 
243 	usb_set_serial_port_data(port, priv);
244 
245 	return 0;
246 }
247 
248 static int klsi_105_port_remove(struct usb_serial_port *port)
249 {
250 	struct klsi_105_private *priv;
251 
252 	priv = usb_get_serial_port_data(port);
253 	kfree(priv);
254 
255 	return 0;
256 }
257 
258 static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port)
259 {
260 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
261 	int retval = 0;
262 	int rc;
263 	int i;
264 	unsigned long line_state;
265 	struct klsi_105_port_settings *cfg;
266 	unsigned long flags;
267 
268 	/* Do a defined restart:
269 	 * Set up sane default baud rate and send the 'READ_ON'
270 	 * vendor command.
271 	 * FIXME: set modem line control (how?)
272 	 * Then read the modem line control and store values in
273 	 * priv->line_state.
274 	 */
275 	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
276 	if (!cfg) {
277 		dev_err(&port->dev, "%s - out of memory for config buffer.\n",
278 				__func__);
279 		return -ENOMEM;
280 	}
281 	cfg->pktlen   = 5;
282 	cfg->baudrate = kl5kusb105a_sio_b9600;
283 	cfg->databits = kl5kusb105a_dtb_8;
284 	cfg->unknown1 = 0;
285 	cfg->unknown2 = 1;
286 	klsi_105_chg_port_settings(port, cfg);
287 
288 	/* set up termios structure */
289 	spin_lock_irqsave(&priv->lock, flags);
290 	priv->termios.c_iflag = tty->termios.c_iflag;
291 	priv->termios.c_oflag = tty->termios.c_oflag;
292 	priv->termios.c_cflag = tty->termios.c_cflag;
293 	priv->termios.c_lflag = tty->termios.c_lflag;
294 	for (i = 0; i < NCCS; i++)
295 		priv->termios.c_cc[i] = tty->termios.c_cc[i];
296 	priv->cfg.pktlen   = cfg->pktlen;
297 	priv->cfg.baudrate = cfg->baudrate;
298 	priv->cfg.databits = cfg->databits;
299 	priv->cfg.unknown1 = cfg->unknown1;
300 	priv->cfg.unknown2 = cfg->unknown2;
301 	spin_unlock_irqrestore(&priv->lock, flags);
302 
303 	/* READ_ON and urb submission */
304 	rc = usb_serial_generic_open(tty, port);
305 	if (rc) {
306 		retval = rc;
307 		goto exit;
308 	}
309 
310 	rc = usb_control_msg(port->serial->dev,
311 			     usb_sndctrlpipe(port->serial->dev, 0),
312 			     KL5KUSB105A_SIO_CONFIGURE,
313 			     USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
314 			     KL5KUSB105A_SIO_CONFIGURE_READ_ON,
315 			     0, /* index */
316 			     NULL,
317 			     0,
318 			     KLSI_TIMEOUT);
319 	if (rc < 0) {
320 		dev_err(&port->dev, "Enabling read failed (error = %d)\n", rc);
321 		retval = rc;
322 	} else
323 		dev_dbg(&port->dev, "%s - enabled reading\n", __func__);
324 
325 	rc = klsi_105_get_line_state(port, &line_state);
326 	if (rc >= 0) {
327 		spin_lock_irqsave(&priv->lock, flags);
328 		priv->line_state = line_state;
329 		spin_unlock_irqrestore(&priv->lock, flags);
330 		dev_dbg(&port->dev, "%s - read line state 0x%lx\n", __func__, line_state);
331 		retval = 0;
332 	} else
333 		retval = rc;
334 
335 exit:
336 	kfree(cfg);
337 	return retval;
338 }
339 
340 static void klsi_105_close(struct usb_serial_port *port)
341 {
342 	int rc;
343 
344 	/* send READ_OFF */
345 	rc = usb_control_msg(port->serial->dev,
346 			     usb_sndctrlpipe(port->serial->dev, 0),
347 			     KL5KUSB105A_SIO_CONFIGURE,
348 			     USB_TYPE_VENDOR | USB_DIR_OUT,
349 			     KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
350 			     0, /* index */
351 			     NULL, 0,
352 			     KLSI_TIMEOUT);
353 	if (rc < 0)
354 		dev_err(&port->dev, "failed to disable read: %d\n", rc);
355 
356 	/* shutdown our bulk reads and writes */
357 	usb_serial_generic_close(port);
358 }
359 
360 /* We need to write a complete 64-byte data block and encode the
361  * number actually sent in the first double-byte, LSB-order. That
362  * leaves at most 62 bytes of payload.
363  */
364 #define KLSI_HDR_LEN		2
365 static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
366 						void *dest, size_t size)
367 {
368 	unsigned char *buf = dest;
369 	int count;
370 
371 	count = kfifo_out_locked(&port->write_fifo, buf + KLSI_HDR_LEN, size,
372 								&port->lock);
373 	put_unaligned_le16(count, buf);
374 
375 	return count + KLSI_HDR_LEN;
376 }
377 
378 /* The data received is preceded by a length double-byte in LSB-first order.
379  */
380 static void klsi_105_process_read_urb(struct urb *urb)
381 {
382 	struct usb_serial_port *port = urb->context;
383 	unsigned char *data = urb->transfer_buffer;
384 	unsigned len;
385 
386 	/* empty urbs seem to happen, we ignore them */
387 	if (!urb->actual_length)
388 		return;
389 
390 	if (urb->actual_length <= KLSI_HDR_LEN) {
391 		dev_dbg(&port->dev, "%s - malformed packet\n", __func__);
392 		return;
393 	}
394 
395 	len = get_unaligned_le16(data);
396 	if (len > urb->actual_length - KLSI_HDR_LEN) {
397 		dev_dbg(&port->dev, "%s - packet length mismatch\n", __func__);
398 		len = urb->actual_length - KLSI_HDR_LEN;
399 	}
400 
401 	tty_insert_flip_string(&port->port, data + KLSI_HDR_LEN, len);
402 	tty_flip_buffer_push(&port->port);
403 }
404 
405 static void klsi_105_set_termios(struct tty_struct *tty,
406 				 struct usb_serial_port *port,
407 				 struct ktermios *old_termios)
408 {
409 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
410 	struct device *dev = &port->dev;
411 	unsigned int iflag = tty->termios.c_iflag;
412 	unsigned int old_iflag = old_termios->c_iflag;
413 	unsigned int cflag = tty->termios.c_cflag;
414 	unsigned int old_cflag = old_termios->c_cflag;
415 	struct klsi_105_port_settings *cfg;
416 	unsigned long flags;
417 	speed_t baud;
418 
419 	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
420 	if (!cfg) {
421 		dev_err(dev, "%s - out of memory for config buffer.\n", __func__);
422 		return;
423 	}
424 
425 	/* lock while we are modifying the settings */
426 	spin_lock_irqsave(&priv->lock, flags);
427 
428 	/*
429 	 * Update baud rate
430 	 */
431 	baud = tty_get_baud_rate(tty);
432 
433 	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
434 		/* reassert DTR and (maybe) RTS on transition from B0 */
435 		if ((old_cflag & CBAUD) == B0) {
436 			dev_dbg(dev, "%s: baud was B0\n", __func__);
437 #if 0
438 			priv->control_state |= TIOCM_DTR;
439 			/* don't set RTS if using hardware flow control */
440 			if (!(old_cflag & CRTSCTS))
441 				priv->control_state |= TIOCM_RTS;
442 			mct_u232_set_modem_ctrl(serial, priv->control_state);
443 #endif
444 		}
445 	}
446 	switch (baud) {
447 	case 0: /* handled below */
448 		break;
449 	case 1200:
450 		priv->cfg.baudrate = kl5kusb105a_sio_b1200;
451 		break;
452 	case 2400:
453 		priv->cfg.baudrate = kl5kusb105a_sio_b2400;
454 		break;
455 	case 4800:
456 		priv->cfg.baudrate = kl5kusb105a_sio_b4800;
457 		break;
458 	case 9600:
459 		priv->cfg.baudrate = kl5kusb105a_sio_b9600;
460 		break;
461 	case 19200:
462 		priv->cfg.baudrate = kl5kusb105a_sio_b19200;
463 		break;
464 	case 38400:
465 		priv->cfg.baudrate = kl5kusb105a_sio_b38400;
466 		break;
467 	case 57600:
468 		priv->cfg.baudrate = kl5kusb105a_sio_b57600;
469 		break;
470 	case 115200:
471 		priv->cfg.baudrate = kl5kusb105a_sio_b115200;
472 		break;
473 	default:
474 		dev_dbg(dev, "KLSI USB->Serial converter: unsupported baudrate request, using default of 9600");
475 		priv->cfg.baudrate = kl5kusb105a_sio_b9600;
476 		baud = 9600;
477 		break;
478 	}
479 	if ((cflag & CBAUD) == B0) {
480 		dev_dbg(dev, "%s: baud is B0\n", __func__);
481 		/* Drop RTS and DTR */
482 		/* maybe this should be simulated by sending read
483 		 * disable and read enable messages?
484 		 */
485 		;
486 #if 0
487 		priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
488 		mct_u232_set_modem_ctrl(serial, priv->control_state);
489 #endif
490 	}
491 	tty_encode_baud_rate(tty, baud, baud);
492 
493 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
494 		/* set the number of data bits */
495 		switch (cflag & CSIZE) {
496 		case CS5:
497 			dev_dbg(dev, "%s - 5 bits/byte not supported\n", __func__);
498 			spin_unlock_irqrestore(&priv->lock, flags);
499 			goto err;
500 		case CS6:
501 			dev_dbg(dev, "%s - 6 bits/byte not supported\n", __func__);
502 			spin_unlock_irqrestore(&priv->lock, flags);
503 			goto err;
504 		case CS7:
505 			priv->cfg.databits = kl5kusb105a_dtb_7;
506 			break;
507 		case CS8:
508 			priv->cfg.databits = kl5kusb105a_dtb_8;
509 			break;
510 		default:
511 			dev_err(dev, "CSIZE was not CS5-CS8, using default of 8\n");
512 			priv->cfg.databits = kl5kusb105a_dtb_8;
513 			break;
514 		}
515 	}
516 
517 	/*
518 	 * Update line control register (LCR)
519 	 */
520 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
521 	    || (cflag & CSTOPB) != (old_cflag & CSTOPB)) {
522 		/* Not currently supported */
523 		tty->termios.c_cflag &= ~(PARENB|PARODD|CSTOPB);
524 #if 0
525 		priv->last_lcr = 0;
526 
527 		/* set the parity */
528 		if (cflag & PARENB)
529 			priv->last_lcr |= (cflag & PARODD) ?
530 				MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
531 		else
532 			priv->last_lcr |= MCT_U232_PARITY_NONE;
533 
534 		/* set the number of stop bits */
535 		priv->last_lcr |= (cflag & CSTOPB) ?
536 			MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
537 
538 		mct_u232_set_line_ctrl(serial, priv->last_lcr);
539 #endif
540 		;
541 	}
542 	/*
543 	 * Set flow control: well, I do not really now how to handle DTR/RTS.
544 	 * Just do what we have seen with SniffUSB on Win98.
545 	 */
546 	if ((iflag & IXOFF) != (old_iflag & IXOFF)
547 	    || (iflag & IXON) != (old_iflag & IXON)
548 	    ||  (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
549 		/* Not currently supported */
550 		tty->termios.c_cflag &= ~CRTSCTS;
551 		/* Drop DTR/RTS if no flow control otherwise assert */
552 #if 0
553 		if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
554 			priv->control_state |= TIOCM_DTR | TIOCM_RTS;
555 		else
556 			priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
557 		mct_u232_set_modem_ctrl(serial, priv->control_state);
558 #endif
559 		;
560 	}
561 	memcpy(cfg, &priv->cfg, sizeof(*cfg));
562 	spin_unlock_irqrestore(&priv->lock, flags);
563 
564 	/* now commit changes to device */
565 	klsi_105_chg_port_settings(port, cfg);
566 err:
567 	kfree(cfg);
568 }
569 
570 #if 0
571 static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
572 {
573 	struct usb_serial_port *port = tty->driver_data;
574 	struct usb_serial *serial = port->serial;
575 	struct mct_u232_private *priv =
576 				(struct mct_u232_private *)port->private;
577 	unsigned char lcr = priv->last_lcr;
578 
579 	dev_dbg(&port->dev, "%s - state=%d\n", __func__, break_state);
580 
581 	/* LOCKING */
582 	if (break_state)
583 		lcr |= MCT_U232_SET_BREAK;
584 
585 	mct_u232_set_line_ctrl(serial, lcr);
586 }
587 #endif
588 
589 static int klsi_105_tiocmget(struct tty_struct *tty)
590 {
591 	struct usb_serial_port *port = tty->driver_data;
592 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
593 	unsigned long flags;
594 	int rc;
595 	unsigned long line_state;
596 
597 	rc = klsi_105_get_line_state(port, &line_state);
598 	if (rc < 0) {
599 		dev_err(&port->dev,
600 			"Reading line control failed (error = %d)\n", rc);
601 		/* better return value? EAGAIN? */
602 		return rc;
603 	}
604 
605 	spin_lock_irqsave(&priv->lock, flags);
606 	priv->line_state = line_state;
607 	spin_unlock_irqrestore(&priv->lock, flags);
608 	dev_dbg(&port->dev, "%s - read line state 0x%lx\n", __func__, line_state);
609 	return (int)line_state;
610 }
611 
612 static int klsi_105_tiocmset(struct tty_struct *tty,
613 			     unsigned int set, unsigned int clear)
614 {
615 	int retval = -EINVAL;
616 
617 /* if this ever gets implemented, it should be done something like this:
618 	struct usb_serial *serial = port->serial;
619 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
620 	unsigned long flags;
621 	int control;
622 
623 	spin_lock_irqsave (&priv->lock, flags);
624 	if (set & TIOCM_RTS)
625 		priv->control_state |= TIOCM_RTS;
626 	if (set & TIOCM_DTR)
627 		priv->control_state |= TIOCM_DTR;
628 	if (clear & TIOCM_RTS)
629 		priv->control_state &= ~TIOCM_RTS;
630 	if (clear & TIOCM_DTR)
631 		priv->control_state &= ~TIOCM_DTR;
632 	control = priv->control_state;
633 	spin_unlock_irqrestore (&priv->lock, flags);
634 	retval = mct_u232_set_modem_ctrl(serial, control);
635 */
636 	return retval;
637 }
638 
639 module_usb_serial_driver(serial_drivers, id_table);
640 
641 MODULE_AUTHOR(DRIVER_AUTHOR);
642 MODULE_DESCRIPTION(DRIVER_DESC);
643 MODULE_LICENSE("GPL");
644