xref: /linux/drivers/usb/serial/ssu100.c (revision a234ca0faa65dcd5cc473915bd925130ebb7b74b)
1 /*
2  * usb-serial driver for Quatech SSU-100
3  *
4  * based on ftdi_sio.c and the original serqt_usb.c from Quatech
5  *
6  */
7 
8 #include <linux/errno.h>
9 #include <linux/init.h>
10 #include <linux/slab.h>
11 #include <linux/tty.h>
12 #include <linux/tty_driver.h>
13 #include <linux/tty_flip.h>
14 #include <linux/module.h>
15 #include <linux/serial.h>
16 #include <linux/usb.h>
17 #include <linux/usb/serial.h>
18 #include <linux/uaccess.h>
19 
20 #define QT_OPEN_CLOSE_CHANNEL       0xca
21 #define QT_SET_GET_DEVICE           0xc2
22 #define QT_SET_GET_REGISTER         0xc0
23 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
24 #define QT_SET_ATF                  0xcd
25 #define QT_GET_SET_UART             0xc1
26 #define QT_TRANSFER_IN              0xc0
27 #define QT_HW_FLOW_CONTROL_MASK     0xc5
28 #define QT_SW_FLOW_CONTROL_MASK     0xc6
29 
30 #define MODEM_CTL_REGISTER         0x04
31 #define MODEM_STATUS_REGISTER      0x06
32 
33 
34 #define SERIAL_LSR_OE       0x02
35 #define SERIAL_LSR_PE       0x04
36 #define SERIAL_LSR_FE       0x08
37 #define SERIAL_LSR_BI       0x10
38 
39 #define SERIAL_LSR_TEMT     0x40
40 
41 #define  SERIAL_MCR_DTR             0x01
42 #define  SERIAL_MCR_RTS             0x02
43 #define  SERIAL_MCR_LOOP            0x10
44 
45 #define  SERIAL_MSR_CTS             0x10
46 #define  SERIAL_MSR_CD              0x80
47 #define  SERIAL_MSR_RI              0x40
48 #define  SERIAL_MSR_DSR             0x20
49 #define  SERIAL_MSR_MASK            0xf0
50 
51 #define  SERIAL_CRTSCTS ((SERIAL_MCR_RTS << 8) | SERIAL_MSR_CTS)
52 
53 #define  SERIAL_8_DATA              0x03
54 #define  SERIAL_7_DATA              0x02
55 #define  SERIAL_6_DATA              0x01
56 #define  SERIAL_5_DATA              0x00
57 
58 #define  SERIAL_ODD_PARITY          0X08
59 #define  SERIAL_EVEN_PARITY         0X18
60 
61 #define  MAX_BAUD_RATE              460800
62 
63 #define ATC_DISABLED                0x00
64 #define DUPMODE_BITS        0xc0
65 #define RR_BITS             0x03
66 #define LOOPMODE_BITS       0x41
67 #define RS232_MODE          0x00
68 #define RTSCTS_TO_CONNECTOR 0x40
69 #define CLKS_X4             0x02
70 #define FULLPWRBIT          0x00000080
71 #define NEXT_BOARD_POWER_BIT        0x00000004
72 
73 static int debug = 1;
74 
75 /* Version Information */
76 #define DRIVER_VERSION "v0.1"
77 #define DRIVER_DESC "Quatech SSU-100 USB to Serial Driver"
78 
79 #define	USB_VENDOR_ID_QUATECH	0x061d	/* Quatech VID */
80 #define QUATECH_SSU100	0xC020	/* SSU100 */
81 
82 static const struct usb_device_id id_table[] = {
83 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU100)},
84 	{}			/* Terminating entry */
85 };
86 
87 MODULE_DEVICE_TABLE(usb, id_table);
88 
89 
90 static struct usb_driver ssu100_driver = {
91 	.name			       = "ssu100",
92 	.probe			       = usb_serial_probe,
93 	.disconnect		       = usb_serial_disconnect,
94 	.id_table		       = id_table,
95 	.suspend		       = usb_serial_suspend,
96 	.resume			       = usb_serial_resume,
97 	.no_dynamic_id		       = 1,
98 	.supports_autosuspend	       = 1,
99 };
100 
101 struct ssu100_port_private {
102 	u8 shadowLSR;
103 	u8 shadowMSR;
104 	wait_queue_head_t delta_msr_wait; /* Used for TIOCMIWAIT */
105 	unsigned short max_packet_size;
106 };
107 
108 static void ssu100_release(struct usb_serial *serial)
109 {
110 	struct ssu100_port_private *priv = usb_get_serial_port_data(*serial->port);
111 
112 	dbg("%s", __func__);
113 	kfree(priv);
114 }
115 
116 static inline int ssu100_control_msg(struct usb_device *dev,
117 				     u8 request, u16 data, u16 index)
118 {
119 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
120 			       request, 0x40, data, index,
121 			       NULL, 0, 300);
122 }
123 
124 static inline int ssu100_setdevice(struct usb_device *dev, u8 *data)
125 {
126 	u16 x = ((u16)(data[1] << 8) | (u16)(data[0]));
127 
128 	return ssu100_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
129 }
130 
131 
132 static inline int ssu100_getdevice(struct usb_device *dev, u8 *data)
133 {
134 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
135 			       QT_SET_GET_DEVICE, 0xc0, 0, 0,
136 			       data, 3, 300);
137 }
138 
139 static inline int ssu100_getregister(struct usb_device *dev,
140 				     unsigned short uart,
141 				     unsigned short reg,
142 				     u8 *data)
143 {
144 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
145 			       QT_SET_GET_REGISTER, 0xc0, reg,
146 			       uart, data, sizeof(*data), 300);
147 
148 }
149 
150 
151 static inline int ssu100_setregister(struct usb_device *dev,
152 				     unsigned short uart,
153 				     u16 data)
154 {
155 	u16 value = (data << 8) | MODEM_CTL_REGISTER;
156 
157 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
158 			       QT_SET_GET_REGISTER, 0x40, value, uart,
159 			       NULL, 0, 300);
160 
161 }
162 
163 #define set_mctrl(dev, set)		update_mctrl((dev), (set), 0)
164 #define clear_mctrl(dev, clear)	update_mctrl((dev), 0, (clear))
165 
166 /* these do not deal with device that have more than 1 port */
167 static inline int update_mctrl(struct usb_device *dev, unsigned int set,
168 			       unsigned int clear)
169 {
170 	unsigned urb_value;
171 	int result;
172 
173 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
174 		dbg("%s - DTR|RTS not being set|cleared", __func__);
175 		return 0;	/* no change */
176 	}
177 
178 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
179 	urb_value = 0;
180 	if (set & TIOCM_DTR)
181 		urb_value |= SERIAL_MCR_DTR;
182 	if (set & TIOCM_RTS)
183 		urb_value |= SERIAL_MCR_RTS;
184 
185 	result = ssu100_setregister(dev, 0, urb_value);
186 	if (result < 0)
187 		dbg("%s Error from MODEM_CTRL urb", __func__);
188 
189 	return result;
190 }
191 
192 static int ssu100_initdevice(struct usb_device *dev)
193 {
194 	u8 *data;
195 	int result = 0;
196 
197 	dbg("%s", __func__);
198 
199 	data = kzalloc(3, GFP_KERNEL);
200 	if (!data)
201 		return -ENOMEM;
202 
203 	result = ssu100_getdevice(dev, data);
204 	if (result < 0) {
205 		dbg("%s - get_device failed %i", __func__, result);
206 		goto out;
207 	}
208 
209 	data[1] &= ~FULLPWRBIT;
210 
211 	result = ssu100_setdevice(dev, data);
212 	if (result < 0) {
213 		dbg("%s - setdevice failed %i", __func__, result);
214 		goto out;
215 	}
216 
217 	result = ssu100_control_msg(dev, QT_GET_SET_PREBUF_TRIG_LVL, 128, 0);
218 	if (result < 0) {
219 		dbg("%s - set prebuffer level failed %i", __func__, result);
220 		goto out;
221 	}
222 
223 	result = ssu100_control_msg(dev, QT_SET_ATF, ATC_DISABLED, 0);
224 	if (result < 0) {
225 		dbg("%s - set ATFprebuffer level failed %i", __func__, result);
226 		goto out;
227 	}
228 
229 	result = ssu100_getdevice(dev, data);
230 	if (result < 0) {
231 		dbg("%s - get_device failed %i", __func__, result);
232 		goto out;
233 	}
234 
235 	data[0] &= ~(RR_BITS | DUPMODE_BITS);
236 	data[0] |= CLKS_X4;
237 	data[1] &= ~(LOOPMODE_BITS);
238 	data[1] |= RS232_MODE;
239 
240 	result = ssu100_setdevice(dev, data);
241 	if (result < 0) {
242 		dbg("%s - setdevice failed %i", __func__, result);
243 		goto out;
244 	}
245 
246 out:	kfree(data);
247 	return result;
248 
249 }
250 
251 
252 static void ssu100_set_termios(struct tty_struct *tty,
253 			       struct usb_serial_port *port,
254 			       struct ktermios *old_termios)
255 {
256 	struct usb_device *dev = port->serial->dev;
257 	struct ktermios *termios = tty->termios;
258 	u16 baud, divisor, remainder;
259 	unsigned int cflag = termios->c_cflag;
260 	u16 urb_value = 0; /* will hold the new flags */
261 	int result;
262 
263 	dbg("%s", __func__);
264 
265 	if (cflag & PARENB) {
266 		if (cflag & PARODD)
267 			urb_value |= SERIAL_ODD_PARITY;
268 		else
269 			urb_value |= SERIAL_EVEN_PARITY;
270 	}
271 
272 	switch (cflag & CSIZE) {
273 	case CS5:
274 		urb_value |= SERIAL_5_DATA;
275 		break;
276 	case CS6:
277 		urb_value |= SERIAL_6_DATA;
278 		break;
279 	case CS7:
280 		urb_value |= SERIAL_7_DATA;
281 		break;
282 	default:
283 	case CS8:
284 		urb_value |= SERIAL_8_DATA;
285 		break;
286 	}
287 
288 	baud = tty_get_baud_rate(tty);
289 	if (!baud)
290 		baud = 9600;
291 
292 	dbg("%s - got baud = %d\n", __func__, baud);
293 
294 
295 	divisor = MAX_BAUD_RATE / baud;
296 	remainder = MAX_BAUD_RATE % baud;
297 	if (((remainder * 2) >= baud) && (baud != 110))
298 		divisor++;
299 
300 	urb_value = urb_value << 8;
301 
302 	result = ssu100_control_msg(dev, QT_GET_SET_UART, divisor, urb_value);
303 	if (result < 0)
304 		dbg("%s - set uart failed", __func__);
305 
306 	if (cflag & CRTSCTS)
307 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
308 					    SERIAL_CRTSCTS, 0);
309 	else
310 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
311 					    0, 0);
312 	if (result < 0)
313 		dbg("%s - set HW flow control failed", __func__);
314 
315 	if (I_IXOFF(tty) || I_IXON(tty)) {
316 		u16 x = ((u16)(START_CHAR(tty) << 8) | (u16)(STOP_CHAR(tty)));
317 
318 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
319 					    x, 0);
320 	} else
321 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
322 					    0, 0);
323 
324 	if (result < 0)
325 		dbg("%s - set SW flow control failed", __func__);
326 
327 }
328 
329 
330 static int ssu100_open(struct tty_struct *tty, struct usb_serial_port *port)
331 {
332 	struct usb_device *dev = port->serial->dev;
333 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
334 	u8 *data;
335 	int result;
336 
337 	dbg("%s - port %d", __func__, port->number);
338 
339 	data = kzalloc(2, GFP_KERNEL);
340 	if (!data)
341 		return -ENOMEM;
342 
343 	result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
344 				 QT_OPEN_CLOSE_CHANNEL,
345 				 QT_TRANSFER_IN, 0x01,
346 				 0, data, 2, 300);
347 	if (result < 0) {
348 		dbg("%s - open failed %i", __func__, result);
349 		kfree(data);
350 		return result;
351 	}
352 
353 	priv->shadowLSR = data[0]  & (SERIAL_LSR_OE | SERIAL_LSR_PE |
354 				      SERIAL_LSR_FE | SERIAL_LSR_BI);
355 
356 	priv->shadowMSR = data[1]  & (SERIAL_MSR_CTS | SERIAL_MSR_DSR |
357 				      SERIAL_MSR_RI | SERIAL_MSR_CD);
358 
359 	kfree(data);
360 
361 /* set to 9600 */
362 	result = ssu100_control_msg(dev, QT_GET_SET_UART, 0x30, 0x0300);
363 	if (result < 0)
364 		dbg("%s - set uart failed", __func__);
365 
366 	if (tty)
367 		ssu100_set_termios(tty, port, tty->termios);
368 
369 	return usb_serial_generic_open(tty, port);
370 }
371 
372 static void ssu100_close(struct usb_serial_port *port)
373 {
374 	dbg("%s", __func__);
375 	usb_serial_generic_close(port);
376 }
377 
378 static int get_serial_info(struct usb_serial_port *port,
379 			   struct serial_struct __user *retinfo)
380 {
381 	struct serial_struct tmp;
382 
383 	if (!retinfo)
384 		return -EFAULT;
385 
386 	memset(&tmp, 0, sizeof(tmp));
387 	tmp.line		= port->serial->minor;
388 	tmp.port		= 0;
389 	tmp.irq			= 0;
390 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
391 	tmp.xmit_fifo_size	= port->bulk_out_size;
392 	tmp.baud_base		= 9600;
393 	tmp.close_delay		= 5*HZ;
394 	tmp.closing_wait	= 30*HZ;
395 
396 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
397 		return -EFAULT;
398 	return 0;
399 }
400 
401 static int ssu100_ioctl(struct tty_struct *tty, struct file *file,
402 		    unsigned int cmd, unsigned long arg)
403 {
404 	struct usb_serial_port *port = tty->driver_data;
405 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
406 
407 	dbg("%s cmd 0x%04x", __func__, cmd);
408 
409 	switch (cmd) {
410 	case TIOCGSERIAL:
411 		return get_serial_info(port,
412 				       (struct serial_struct __user *) arg);
413 
414 	case TIOCMIWAIT:
415 		while (priv != NULL) {
416 			u8 prevMSR = priv->shadowMSR & SERIAL_MSR_MASK;
417 			interruptible_sleep_on(&priv->delta_msr_wait);
418 			/* see if a signal did it */
419 			if (signal_pending(current))
420 				return -ERESTARTSYS;
421 			else {
422 				u8 diff = (priv->shadowMSR & SERIAL_MSR_MASK) ^ prevMSR;
423 				if (!diff)
424 					return -EIO; /* no change => error */
425 
426 				/* Return 0 if caller wanted to know about
427 				   these bits */
428 
429 				if (((arg & TIOCM_RNG) && (diff & SERIAL_MSR_RI)) ||
430 				    ((arg & TIOCM_DSR) && (diff & SERIAL_MSR_DSR)) ||
431 				    ((arg & TIOCM_CD) && (diff & SERIAL_MSR_CD)) ||
432 				    ((arg & TIOCM_CTS) && (diff & SERIAL_MSR_CTS)))
433 					return 0;
434 			}
435 		}
436 		return 0;
437 
438 	default:
439 		break;
440 	}
441 
442 	dbg("%s arg not supported", __func__);
443 
444 	return -ENOIOCTLCMD;
445 }
446 
447 static void ssu100_set_max_packet_size(struct usb_serial_port *port)
448 {
449 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
450 	struct usb_serial *serial = port->serial;
451 	struct usb_device *udev = serial->dev;
452 
453 	struct usb_interface *interface = serial->interface;
454 	struct usb_endpoint_descriptor *ep_desc = &interface->cur_altsetting->endpoint[1].desc;
455 
456 	unsigned num_endpoints;
457 	int i;
458 
459 	num_endpoints = interface->cur_altsetting->desc.bNumEndpoints;
460 	dev_info(&udev->dev, "Number of endpoints %d\n", num_endpoints);
461 
462 	for (i = 0; i < num_endpoints; i++) {
463 		dev_info(&udev->dev, "Endpoint %d MaxPacketSize %d\n", i+1,
464 			interface->cur_altsetting->endpoint[i].desc.wMaxPacketSize);
465 		ep_desc = &interface->cur_altsetting->endpoint[i].desc;
466 	}
467 
468 	/* set max packet size based on descriptor */
469 	priv->max_packet_size = ep_desc->wMaxPacketSize;
470 
471 	dev_info(&udev->dev, "Setting MaxPacketSize %d\n", priv->max_packet_size);
472 }
473 
474 static int ssu100_attach(struct usb_serial *serial)
475 {
476 	struct ssu100_port_private *priv;
477 	struct usb_serial_port *port = *serial->port;
478 
479 	dbg("%s", __func__);
480 
481 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
482 	if (!priv) {
483 		dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n", __func__,
484 			sizeof(*priv));
485 		return -ENOMEM;
486 	}
487 
488 	init_waitqueue_head(&priv->delta_msr_wait);
489 	usb_set_serial_port_data(port, priv);
490 
491 	ssu100_set_max_packet_size(port);
492 
493 	return ssu100_initdevice(serial->dev);
494 }
495 
496 static int ssu100_tiocmget(struct tty_struct *tty, struct file *file)
497 {
498 	struct usb_serial_port *port = tty->driver_data;
499 	struct usb_device *dev = port->serial->dev;
500 	u8 *d;
501 	int r;
502 
503 	dbg("%s\n", __func__);
504 
505 	d = kzalloc(2, GFP_KERNEL);
506 	if (!d)
507 		return -ENOMEM;
508 
509 	r = ssu100_getregister(dev, 0, MODEM_CTL_REGISTER, d);
510 	if (r < 0)
511 		goto mget_out;
512 
513 	r = ssu100_getregister(dev, 0, MODEM_STATUS_REGISTER, d+1);
514 	if (r < 0)
515 		goto mget_out;
516 
517 	r = (d[0] & SERIAL_MCR_DTR ? TIOCM_DTR : 0) |
518 		(d[0] & SERIAL_MCR_RTS ? TIOCM_RTS : 0) |
519 		(d[1] & SERIAL_MSR_CTS ? TIOCM_CTS : 0) |
520 		(d[1] & SERIAL_MSR_CD ? TIOCM_CAR : 0) |
521 		(d[1] & SERIAL_MSR_RI ? TIOCM_RI : 0) |
522 		(d[1] & SERIAL_MSR_DSR ? TIOCM_DSR : 0);
523 
524 mget_out:
525 	kfree(d);
526 	return r;
527 }
528 
529 static int ssu100_tiocmset(struct tty_struct *tty, struct file *file,
530 			   unsigned int set, unsigned int clear)
531 {
532 	struct usb_serial_port *port = tty->driver_data;
533 	struct usb_device *dev = port->serial->dev;
534 
535 	dbg("%s\n", __func__);
536 	return update_mctrl(dev, set, clear);
537 }
538 
539 static void ssu100_dtr_rts(struct usb_serial_port *port, int on)
540 {
541 	struct usb_device *dev = port->serial->dev;
542 
543 	dbg("%s\n", __func__);
544 
545 	mutex_lock(&port->serial->disc_mutex);
546 	if (!port->serial->disconnected) {
547 		/* Disable flow control */
548 		if (!on &&
549 		    ssu100_setregister(dev, 0, 0) < 0)
550 			dev_err(&port->dev, "error from flowcontrol urb\n");
551 		/* drop RTS and DTR */
552 		if (on)
553 			set_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
554 		else
555 			clear_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
556 	}
557 	mutex_unlock(&port->serial->disc_mutex);
558 }
559 
560 static int ssu100_process_packet(struct tty_struct *tty,
561 				 struct usb_serial_port *port,
562 				 struct ssu100_port_private *priv,
563 				 char *packet, int len)
564 {
565 	int i;
566 	char flag;
567 	char *ch;
568 
569 	dbg("%s - port %d", __func__, port->number);
570 
571 	if (len < 4) {
572 		dbg("%s - malformed packet", __func__);
573 		return 0;
574 	}
575 
576 	if ((packet[0] == 0x1b) && (packet[1] == 0x1b) &&
577 	    ((packet[2] == 0x00) || (packet[2] == 0x01))) {
578 		if (packet[2] == 0x00)
579 			priv->shadowLSR = packet[3] & (SERIAL_LSR_OE |
580 						       SERIAL_LSR_PE |
581 						       SERIAL_LSR_FE |
582 						       SERIAL_LSR_BI);
583 
584 		if (packet[2] == 0x01) {
585 			priv->shadowMSR = packet[3];
586 			wake_up_interruptible(&priv->delta_msr_wait);
587 		}
588 
589 		len -= 4;
590 		ch = packet + 4;
591 	} else
592 		ch = packet;
593 
594 	if (!len)
595 		return 0;	/* status only */
596 
597 	if (port->port.console && port->sysrq) {
598 		for (i = 0; i < len; i++, ch++) {
599 			if (!usb_serial_handle_sysrq_char(tty, port, *ch))
600 				tty_insert_flip_char(tty, *ch, flag);
601 		}
602 	} else
603 		tty_insert_flip_string_fixed_flag(tty, ch, flag, len);
604 
605 	return len;
606 }
607 
608 static void ssu100_process_read_urb(struct urb *urb)
609 {
610 	struct usb_serial_port *port = urb->context;
611 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
612 	char *data = (char *)urb->transfer_buffer;
613 	struct tty_struct *tty;
614 	int count = 0;
615 	int i;
616 	int len;
617 
618 	dbg("%s", __func__);
619 
620 	tty = tty_port_tty_get(&port->port);
621 	if (!tty)
622 		return;
623 
624 	for (i = 0; i < urb->actual_length; i += priv->max_packet_size) {
625 		len = min_t(int, urb->actual_length - i, priv->max_packet_size);
626 		count += ssu100_process_packet(tty, port, priv, &data[i], len);
627 	}
628 
629 	if (count)
630 		tty_flip_buffer_push(tty);
631 	tty_kref_put(tty);
632 }
633 
634 
635 static struct usb_serial_driver ssu100_device = {
636 	.driver = {
637 		.owner = THIS_MODULE,
638 		.name = "ssu100",
639 	},
640 	.description	     = DRIVER_DESC,
641 	.id_table	     = id_table,
642 	.usb_driver	     = &ssu100_driver,
643 	.num_ports	     = 1,
644 	.bulk_in_size        = 256,
645 	.bulk_out_size       = 256,
646 	.open		     = ssu100_open,
647 	.close		     = ssu100_close,
648 	.attach              = ssu100_attach,
649 	.release             = ssu100_release,
650 	.dtr_rts             = ssu100_dtr_rts,
651 	.process_read_urb    = ssu100_process_read_urb,
652 	.tiocmget            = ssu100_tiocmget,
653 	.tiocmset            = ssu100_tiocmset,
654 	.ioctl               = ssu100_ioctl,
655 	.set_termios         = ssu100_set_termios,
656 };
657 
658 static int __init ssu100_init(void)
659 {
660 	int retval;
661 
662 	dbg("%s", __func__);
663 
664 	/* register with usb-serial */
665 	retval = usb_serial_register(&ssu100_device);
666 
667 	if (retval)
668 		goto failed_usb_sio_register;
669 
670 	retval = usb_register(&ssu100_driver);
671 	if (retval)
672 		goto failed_usb_register;
673 
674 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
675 	       DRIVER_DESC "\n");
676 
677 	return 0;
678 
679 failed_usb_register:
680 	usb_serial_deregister(&ssu100_device);
681 failed_usb_sio_register:
682 	return retval;
683 }
684 
685 static void __exit ssu100_exit(void)
686 {
687 	usb_deregister(&ssu100_driver);
688 	usb_serial_deregister(&ssu100_device);
689 }
690 
691 module_init(ssu100_init);
692 module_exit(ssu100_exit);
693 
694 MODULE_DESCRIPTION(DRIVER_DESC);
695 MODULE_LICENSE("GPL");
696 
697 module_param(debug, bool, S_IRUGO | S_IWUSR);
698 MODULE_PARM_DESC(debug, "Debug enabled or not");
699