xref: /openbmc/linux/drivers/usb/serial/quatech2.c (revision f35e839a)
1 /*
2  * usb-serial driver for Quatech USB 2 devices
3  *
4  * Copyright (C) 2012 Bill Pemberton (wfp5p@virginia.edu)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License version 2
8  * as published by the Free Software Foundation.
9  *
10  *
11  *  These devices all have only 1 bulk in and 1 bulk out that is shared
12  *  for all serial ports.
13  *
14  */
15 
16 #include <asm/unaligned.h>
17 #include <linux/errno.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/tty.h>
21 #include <linux/tty_driver.h>
22 #include <linux/tty_flip.h>
23 #include <linux/module.h>
24 #include <linux/serial.h>
25 #include <linux/usb.h>
26 #include <linux/usb/serial.h>
27 #include <linux/serial_reg.h>
28 #include <linux/uaccess.h>
29 
30 /* default urb timeout for usb operations */
31 #define QT2_USB_TIMEOUT USB_CTRL_SET_TIMEOUT
32 
33 #define QT_OPEN_CLOSE_CHANNEL       0xca
34 #define QT_SET_GET_DEVICE           0xc2
35 #define QT_SET_GET_REGISTER         0xc0
36 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
37 #define QT_SET_ATF                  0xcd
38 #define QT_TRANSFER_IN              0xc0
39 #define QT_HW_FLOW_CONTROL_MASK     0xc5
40 #define QT_SW_FLOW_CONTROL_MASK     0xc6
41 #define QT2_BREAK_CONTROL	    0xc8
42 #define QT2_GET_SET_UART            0xc1
43 #define QT2_FLUSH_DEVICE	    0xc4
44 #define QT2_GET_SET_QMCR            0xe1
45 #define QT2_QMCR_RS232              0x40
46 #define QT2_QMCR_RS422              0x10
47 
48 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
49 
50 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
51 
52 /* status bytes for the device */
53 #define QT2_CONTROL_BYTE    0x1b
54 #define QT2_LINE_STATUS     0x00  /* following 1 byte is line status */
55 #define QT2_MODEM_STATUS    0x01  /* following 1 byte is modem status */
56 #define QT2_XMIT_HOLD       0x02  /* following 2 bytes are ?? */
57 #define QT2_CHANGE_PORT     0x03  /* following 1 byte is port to change to */
58 #define QT2_REC_FLUSH       0x04  /* no following info */
59 #define QT2_XMIT_FLUSH      0x05  /* no following info */
60 #define QT2_CONTROL_ESCAPE  0xff  /* pass through previous 2 control bytes */
61 
62 #define  MAX_BAUD_RATE              921600
63 #define  DEFAULT_BAUD_RATE          9600
64 
65 #define QT2_WRITE_BUFFER_SIZE   512  /* size of write buffer */
66 #define QT2_WRITE_CONTROL_SIZE  5    /* control bytes used for a write */
67 
68 #define DRIVER_DESC "Quatech 2nd gen USB to Serial Driver"
69 
70 #define	USB_VENDOR_ID_QUATECH	0x061d
71 #define QUATECH_SSU2_100	0xC120	/* RS232 single port */
72 #define QUATECH_DSU2_100	0xC140	/* RS232 dual port */
73 #define QUATECH_DSU2_400	0xC150	/* RS232/422/485 dual port */
74 #define QUATECH_QSU2_100	0xC160	/* RS232 four port */
75 #define QUATECH_QSU2_400	0xC170	/* RS232/422/485 four port */
76 #define QUATECH_ESU2_100	0xC1A0	/* RS232 eight port */
77 #define QUATECH_ESU2_400	0xC180	/* RS232/422/485 eight port */
78 
79 struct qt2_device_detail {
80 	int product_id;
81 	int num_ports;
82 };
83 
84 #define QT_DETAILS(prod, ports)	\
85 	.product_id = (prod),   \
86 	.num_ports = (ports)
87 
88 static const struct qt2_device_detail qt2_device_details[] = {
89 	{QT_DETAILS(QUATECH_SSU2_100, 1)},
90 	{QT_DETAILS(QUATECH_DSU2_400, 2)},
91 	{QT_DETAILS(QUATECH_DSU2_100, 2)},
92 	{QT_DETAILS(QUATECH_QSU2_400, 4)},
93 	{QT_DETAILS(QUATECH_QSU2_100, 4)},
94 	{QT_DETAILS(QUATECH_ESU2_400, 8)},
95 	{QT_DETAILS(QUATECH_ESU2_100, 8)},
96 	{QT_DETAILS(0, 0)}	/* Terminating entry */
97 };
98 
99 static const struct usb_device_id id_table[] = {
100 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU2_100)},
101 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_100)},
102 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_400)},
103 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_100)},
104 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_400)},
105 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_100)},
106 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_400)},
107 	{}			/* Terminating entry */
108 };
109 MODULE_DEVICE_TABLE(usb, id_table);
110 
111 struct qt2_serial_private {
112 	unsigned char current_port;  /* current port for incoming data */
113 
114 	struct urb	*read_urb;   /* shared among all ports */
115 	char		read_buffer[512];
116 };
117 
118 struct qt2_port_private {
119 	u8   device_port;
120 
121 	spinlock_t urb_lock;
122 	bool       urb_in_use;
123 	struct urb *write_urb;
124 	char       write_buffer[QT2_WRITE_BUFFER_SIZE];
125 
126 	spinlock_t  lock;
127 	u8          shadowLSR;
128 	u8          shadowMSR;
129 
130 	struct usb_serial_port *port;
131 };
132 
133 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch);
134 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch);
135 static void qt2_write_bulk_callback(struct urb *urb);
136 static void qt2_read_bulk_callback(struct urb *urb);
137 
138 static void qt2_release(struct usb_serial *serial)
139 {
140 	struct qt2_serial_private *serial_priv;
141 
142 	serial_priv = usb_get_serial_data(serial);
143 
144 	usb_free_urb(serial_priv->read_urb);
145 	kfree(serial_priv);
146 }
147 
148 static inline int calc_baud_divisor(int baudrate)
149 {
150 	int divisor, rem;
151 
152 	divisor = MAX_BAUD_RATE / baudrate;
153 	rem = MAX_BAUD_RATE % baudrate;
154 	/* Round to nearest divisor */
155 	if (((rem * 2) >= baudrate) && (baudrate != 110))
156 		divisor++;
157 
158 	return divisor;
159 }
160 
161 static inline int qt2_set_port_config(struct usb_device *dev,
162 				      unsigned char port_number,
163 				      u16 baudrate, u16 lcr)
164 {
165 	int divisor = calc_baud_divisor(baudrate);
166 	u16 index = ((u16) (lcr << 8) | (u16) (port_number));
167 
168 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
169 			       QT2_GET_SET_UART, 0x40,
170 			       divisor, index, NULL, 0, QT2_USB_TIMEOUT);
171 }
172 
173 static inline int qt2_control_msg(struct usb_device *dev,
174 				  u8 request, u16 data, u16 index)
175 {
176 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
177 			       request, 0x40, data, index,
178 			       NULL, 0, QT2_USB_TIMEOUT);
179 }
180 
181 static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
182 {
183 	u16 x = ((u16) (data[1] << 8) | (u16) (data[0]));
184 
185 	return qt2_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
186 }
187 
188 
189 static inline int qt2_getdevice(struct usb_device *dev, u8 *data)
190 {
191 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
192 			       QT_SET_GET_DEVICE, 0xc0, 0, 0,
193 			       data, 3, QT2_USB_TIMEOUT);
194 }
195 
196 static inline int qt2_getregister(struct usb_device *dev,
197 				  u8 uart,
198 				  u8 reg,
199 				  u8 *data)
200 {
201 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
202 			       QT_SET_GET_REGISTER, 0xc0, reg,
203 			       uart, data, sizeof(*data), QT2_USB_TIMEOUT);
204 
205 }
206 
207 static inline int qt2_setregister(struct usb_device *dev,
208 				  u8 uart, u8 reg, u16 data)
209 {
210 	u16 value = (data << 8) | reg;
211 
212 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
213 			       QT_SET_GET_REGISTER, 0x40, value, uart,
214 			       NULL, 0, QT2_USB_TIMEOUT);
215 }
216 
217 static inline int update_mctrl(struct qt2_port_private *port_priv,
218 			       unsigned int set, unsigned int clear)
219 {
220 	struct usb_serial_port *port = port_priv->port;
221 	struct usb_device *dev = port->serial->dev;
222 	unsigned urb_value;
223 	int status;
224 
225 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
226 		dev_dbg(&port->dev,
227 			"update_mctrl - DTR|RTS not being set|cleared\n");
228 		return 0;	/* no change */
229 	}
230 
231 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
232 	urb_value = 0;
233 	if (set & TIOCM_DTR)
234 		urb_value |= UART_MCR_DTR;
235 	if (set & TIOCM_RTS)
236 		urb_value |= UART_MCR_RTS;
237 
238 	status = qt2_setregister(dev, port_priv->device_port, UART_MCR,
239 				 urb_value);
240 	if (status < 0)
241 		dev_err(&port->dev,
242 			"update_mctrl - Error from MODEM_CTRL urb: %i\n",
243 			status);
244 	return status;
245 }
246 
247 static int qt2_calc_num_ports(struct usb_serial *serial)
248 {
249 	struct qt2_device_detail d;
250 	int i;
251 
252 	for (i = 0; d = qt2_device_details[i], d.product_id != 0; i++) {
253 		if (d.product_id == le16_to_cpu(serial->dev->descriptor.idProduct))
254 			return d.num_ports;
255 	}
256 
257 	/* we didn't recognize the device */
258 	dev_err(&serial->dev->dev,
259 		 "don't know the number of ports, assuming 1\n");
260 
261 	return 1;
262 }
263 
264 static void qt2_set_termios(struct tty_struct *tty,
265 			    struct usb_serial_port *port,
266 			    struct ktermios *old_termios)
267 {
268 	struct usb_device *dev = port->serial->dev;
269 	struct qt2_port_private *port_priv;
270 	struct ktermios *termios = &tty->termios;
271 	u16 baud;
272 	unsigned int cflag = termios->c_cflag;
273 	u16 new_lcr = 0;
274 	int status;
275 
276 	port_priv = usb_get_serial_port_data(port);
277 
278 	if (cflag & PARENB) {
279 		if (cflag & PARODD)
280 			new_lcr |= UART_LCR_PARITY;
281 		else
282 			new_lcr |= SERIAL_EVEN_PARITY;
283 	}
284 
285 	switch (cflag & CSIZE) {
286 	case CS5:
287 		new_lcr |= UART_LCR_WLEN5;
288 		break;
289 	case CS6:
290 		new_lcr |= UART_LCR_WLEN6;
291 		break;
292 	case CS7:
293 		new_lcr |= UART_LCR_WLEN7;
294 		break;
295 	default:
296 	case CS8:
297 		new_lcr |= UART_LCR_WLEN8;
298 		break;
299 	}
300 
301 	baud = tty_get_baud_rate(tty);
302 	if (!baud)
303 		baud = 9600;
304 
305 	status = qt2_set_port_config(dev, port_priv->device_port, baud,
306 				     new_lcr);
307 	if (status < 0)
308 		dev_err(&port->dev, "%s - qt2_set_port_config failed: %i\n",
309 			__func__, status);
310 
311 	if (cflag & CRTSCTS)
312 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
313 					 SERIAL_CRTSCTS,
314 					 port_priv->device_port);
315 	else
316 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
317 					 0, port_priv->device_port);
318 	if (status < 0)
319 		dev_err(&port->dev, "%s - set HW flow control failed: %i\n",
320 			__func__, status);
321 
322 	if (I_IXOFF(tty) || I_IXON(tty)) {
323 		u16 x = ((u16) (START_CHAR(tty) << 8) | (u16) (STOP_CHAR(tty)));
324 
325 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
326 					 x, port_priv->device_port);
327 	} else
328 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
329 					 0, port_priv->device_port);
330 
331 	if (status < 0)
332 		dev_err(&port->dev, "%s - set SW flow control failed: %i\n",
333 			__func__, status);
334 
335 }
336 
337 static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port)
338 {
339 	struct usb_serial *serial;
340 	struct qt2_port_private *port_priv;
341 	u8 *data;
342 	u16 device_port;
343 	int status;
344 	unsigned long flags;
345 
346 	device_port = (u16) (port->number - port->serial->minor);
347 
348 	serial = port->serial;
349 
350 	port_priv = usb_get_serial_port_data(port);
351 
352 	/* set the port to RS232 mode */
353 	status = qt2_control_msg(serial->dev, QT2_GET_SET_QMCR,
354 				 QT2_QMCR_RS232, device_port);
355 	if (status < 0) {
356 		dev_err(&port->dev,
357 			"%s failed to set RS232 mode for port %i error %i\n",
358 			__func__, device_port, status);
359 		return status;
360 	}
361 
362 	data = kzalloc(2, GFP_KERNEL);
363 	if (!data)
364 		return -ENOMEM;
365 
366 	/* open the port */
367 	status = usb_control_msg(serial->dev,
368 				 usb_rcvctrlpipe(serial->dev, 0),
369 				 QT_OPEN_CLOSE_CHANNEL,
370 				 0xc0, 0,
371 				 device_port, data, 2, QT2_USB_TIMEOUT);
372 
373 	if (status < 0) {
374 		dev_err(&port->dev, "%s - open port failed %i", __func__,
375 			status);
376 		kfree(data);
377 		return status;
378 	}
379 
380 	spin_lock_irqsave(&port_priv->lock, flags);
381 	port_priv->shadowLSR = data[0];
382 	port_priv->shadowMSR = data[1];
383 	spin_unlock_irqrestore(&port_priv->lock, flags);
384 
385 	kfree(data);
386 
387 	/* set to default speed and 8bit word size */
388 	status = qt2_set_port_config(serial->dev, device_port,
389 				     DEFAULT_BAUD_RATE, UART_LCR_WLEN8);
390 	if (status < 0) {
391 		dev_err(&port->dev,
392 			"%s - initial setup failed for port %i (%i)\n",
393 			__func__, port->number, device_port);
394 		return status;
395 	}
396 
397 	port_priv->device_port = (u8) device_port;
398 
399 	if (tty)
400 		qt2_set_termios(tty, port, &tty->termios);
401 
402 	return 0;
403 
404 }
405 
406 static void qt2_close(struct usb_serial_port *port)
407 {
408 	struct usb_serial *serial;
409 	struct qt2_port_private *port_priv;
410 	unsigned long flags;
411 	int i;
412 
413 	serial = port->serial;
414 	port_priv = usb_get_serial_port_data(port);
415 
416 	spin_lock_irqsave(&port_priv->urb_lock, flags);
417 	usb_kill_urb(port_priv->write_urb);
418 	port_priv->urb_in_use = false;
419 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
420 
421 	/* flush the port transmit buffer */
422 	i = usb_control_msg(serial->dev,
423 			    usb_rcvctrlpipe(serial->dev, 0),
424 			    QT2_FLUSH_DEVICE, 0x40, 1,
425 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
426 
427 	if (i < 0)
428 		dev_err(&port->dev, "%s - transmit buffer flush failed: %i\n",
429 			__func__, i);
430 
431 	/* flush the port receive buffer */
432 	i = usb_control_msg(serial->dev,
433 			    usb_rcvctrlpipe(serial->dev, 0),
434 			    QT2_FLUSH_DEVICE, 0x40, 0,
435 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
436 
437 	if (i < 0)
438 		dev_err(&port->dev, "%s - receive buffer flush failed: %i\n",
439 			__func__, i);
440 
441 	/* close the port */
442 	i = usb_control_msg(serial->dev,
443 			    usb_sndctrlpipe(serial->dev, 0),
444 			    QT_OPEN_CLOSE_CHANNEL,
445 			    0x40, 0,
446 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
447 
448 	if (i < 0)
449 		dev_err(&port->dev, "%s - close port failed %i\n",
450 			__func__, i);
451 }
452 
453 static void qt2_disconnect(struct usb_serial *serial)
454 {
455 	struct qt2_serial_private *serial_priv = usb_get_serial_data(serial);
456 
457 	usb_kill_urb(serial_priv->read_urb);
458 }
459 
460 static int get_serial_info(struct usb_serial_port *port,
461 			   struct serial_struct __user *retinfo)
462 {
463 	struct serial_struct tmp;
464 
465 	if (!retinfo)
466 		return -EFAULT;
467 
468 	memset(&tmp, 0, sizeof(tmp));
469 	tmp.line		= port->serial->minor;
470 	tmp.port		= 0;
471 	tmp.irq			= 0;
472 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
473 	tmp.xmit_fifo_size	= port->bulk_out_size;
474 	tmp.baud_base		= 9600;
475 	tmp.close_delay		= 5*HZ;
476 	tmp.closing_wait	= 30*HZ;
477 
478 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
479 		return -EFAULT;
480 	return 0;
481 }
482 
483 static int qt2_ioctl(struct tty_struct *tty,
484 		     unsigned int cmd, unsigned long arg)
485 {
486 	struct usb_serial_port *port = tty->driver_data;
487 
488 	switch (cmd) {
489 	case TIOCGSERIAL:
490 		return get_serial_info(port,
491 				       (struct serial_struct __user *)arg);
492 	default:
493 		break;
494 	}
495 
496 	return -ENOIOCTLCMD;
497 }
498 
499 static void qt2_process_status(struct usb_serial_port *port, unsigned char *ch)
500 {
501 	switch (*ch) {
502 	case QT2_LINE_STATUS:
503 		qt2_update_lsr(port, ch + 1);
504 		break;
505 	case QT2_MODEM_STATUS:
506 		qt2_update_msr(port, ch + 1);
507 		break;
508 	}
509 }
510 
511 /* not needed, kept to document functionality */
512 static void qt2_process_xmit_empty(struct usb_serial_port *port,
513 				   unsigned char *ch)
514 {
515 	int bytes_written;
516 
517 	bytes_written = (int)(*ch) + (int)(*(ch + 1) << 4);
518 }
519 
520 /* not needed, kept to document functionality */
521 static void qt2_process_flush(struct usb_serial_port *port, unsigned char *ch)
522 {
523 	return;
524 }
525 
526 void qt2_process_read_urb(struct urb *urb)
527 {
528 	struct usb_serial *serial;
529 	struct qt2_serial_private *serial_priv;
530 	struct usb_serial_port *port;
531 	struct qt2_port_private *port_priv;
532 	bool escapeflag;
533 	unsigned char *ch;
534 	int i;
535 	unsigned char newport;
536 	int len = urb->actual_length;
537 
538 	if (!len)
539 		return;
540 
541 	ch = urb->transfer_buffer;
542 	serial = urb->context;
543 	serial_priv = usb_get_serial_data(serial);
544 	port = serial->port[serial_priv->current_port];
545 	port_priv = usb_get_serial_port_data(port);
546 
547 	for (i = 0; i < urb->actual_length; i++) {
548 		ch = (unsigned char *)urb->transfer_buffer + i;
549 		if ((i <= (len - 3)) &&
550 		    (*ch == QT2_CONTROL_BYTE) &&
551 		    (*(ch + 1) == QT2_CONTROL_BYTE)) {
552 			escapeflag = false;
553 			switch (*(ch + 2)) {
554 			case QT2_LINE_STATUS:
555 			case QT2_MODEM_STATUS:
556 				if (i > (len - 4)) {
557 					dev_warn(&port->dev,
558 						 "%s - status message too short\n",
559 						__func__);
560 					break;
561 				}
562 				qt2_process_status(port, ch + 2);
563 				i += 3;
564 				escapeflag = true;
565 				break;
566 			case QT2_XMIT_HOLD:
567 				if (i > (len - 5)) {
568 					dev_warn(&port->dev,
569 						 "%s - xmit_empty message too short\n",
570 						 __func__);
571 					break;
572 				}
573 				qt2_process_xmit_empty(port, ch + 3);
574 				i += 4;
575 				escapeflag = true;
576 				break;
577 			case QT2_CHANGE_PORT:
578 				if (i > (len - 4)) {
579 					dev_warn(&port->dev,
580 						 "%s - change_port message too short\n",
581 						 __func__);
582 					break;
583 				}
584 				tty_flip_buffer_push(&port->port);
585 
586 				newport = *(ch + 3);
587 
588 				if (newport > serial->num_ports) {
589 					dev_err(&port->dev,
590 						"%s - port change to invalid port: %i\n",
591 						__func__, newport);
592 					break;
593 				}
594 
595 				serial_priv->current_port = newport;
596 				port = serial->port[serial_priv->current_port];
597 				port_priv = usb_get_serial_port_data(port);
598 				i += 3;
599 				escapeflag = true;
600 				break;
601 			case QT2_REC_FLUSH:
602 			case QT2_XMIT_FLUSH:
603 				qt2_process_flush(port, ch + 2);
604 				i += 2;
605 				escapeflag = true;
606 				break;
607 			case QT2_CONTROL_ESCAPE:
608 				tty_buffer_request_room(&port->port, 2);
609 				tty_insert_flip_string(&port->port, ch, 2);
610 				i += 2;
611 				escapeflag = true;
612 				break;
613 			default:
614 				dev_warn(&port->dev,
615 					 "%s - unsupported command %i\n",
616 					 __func__, *(ch + 2));
617 				break;
618 			}
619 			if (escapeflag)
620 				continue;
621 		}
622 
623 		tty_buffer_request_room(&port->port, 1);
624 		tty_insert_flip_string(&port->port, ch, 1);
625 	}
626 
627 	tty_flip_buffer_push(&port->port);
628 }
629 
630 static void qt2_write_bulk_callback(struct urb *urb)
631 {
632 	struct usb_serial_port *port;
633 	struct qt2_port_private *port_priv;
634 
635 	port = urb->context;
636 	port_priv = usb_get_serial_port_data(port);
637 
638 	spin_lock(&port_priv->urb_lock);
639 
640 	port_priv->urb_in_use = false;
641 	usb_serial_port_softint(port);
642 
643 	spin_unlock(&port_priv->urb_lock);
644 
645 }
646 
647 static void qt2_read_bulk_callback(struct urb *urb)
648 {
649 	struct usb_serial *serial = urb->context;
650 	int status;
651 
652 	if (urb->status) {
653 		dev_warn(&serial->dev->dev,
654 			 "%s - non-zero urb status: %i\n", __func__,
655 			 urb->status);
656 		return;
657 	}
658 
659 	qt2_process_read_urb(urb);
660 
661 	status = usb_submit_urb(urb, GFP_ATOMIC);
662 	if (status != 0)
663 		dev_err(&serial->dev->dev,
664 			"%s - resubmit read urb failed: %i\n",
665 			__func__, status);
666 }
667 
668 static int qt2_setup_urbs(struct usb_serial *serial)
669 {
670 	struct usb_serial_port *port0;
671 	struct qt2_serial_private *serial_priv;
672 	int status;
673 
674 	port0 = serial->port[0];
675 
676 	serial_priv = usb_get_serial_data(serial);
677 	serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
678 	if (!serial_priv->read_urb) {
679 		dev_err(&serial->dev->dev, "No free urbs available\n");
680 		return -ENOMEM;
681 	}
682 
683 	usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
684 			  usb_rcvbulkpipe(serial->dev,
685 					  port0->bulk_in_endpointAddress),
686 			  serial_priv->read_buffer,
687 			  sizeof(serial_priv->read_buffer),
688 			  qt2_read_bulk_callback, serial);
689 
690 	status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
691 	if (status != 0) {
692 		dev_err(&serial->dev->dev,
693 			"%s - submit read urb failed %i\n", __func__, status);
694 		usb_free_urb(serial_priv->read_urb);
695 		return status;
696 	}
697 
698 	return 0;
699 }
700 
701 static int qt2_attach(struct usb_serial *serial)
702 {
703 	struct qt2_serial_private *serial_priv;
704 	int status;
705 
706 	/* power on unit */
707 	status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
708 				 0xc2, 0x40, 0x8000, 0, NULL, 0,
709 				 QT2_USB_TIMEOUT);
710 	if (status < 0) {
711 		dev_err(&serial->dev->dev,
712 			"%s - failed to power on unit: %i\n", __func__, status);
713 		return status;
714 	}
715 
716 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
717 	if (!serial_priv) {
718 		dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
719 		return -ENOMEM;
720 	}
721 
722 	usb_set_serial_data(serial, serial_priv);
723 
724 	status = qt2_setup_urbs(serial);
725 	if (status != 0)
726 		goto attach_failed;
727 
728 	return 0;
729 
730 attach_failed:
731 	kfree(serial_priv);
732 	return status;
733 }
734 
735 static int qt2_port_probe(struct usb_serial_port *port)
736 {
737 	struct usb_serial *serial = port->serial;
738 	struct qt2_port_private *port_priv;
739 	u8 bEndpointAddress;
740 
741 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
742 	if (!port_priv)
743 		return -ENOMEM;
744 
745 	spin_lock_init(&port_priv->lock);
746 	spin_lock_init(&port_priv->urb_lock);
747 	port_priv->port = port;
748 
749 	port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
750 	if (!port_priv->write_urb) {
751 		kfree(port_priv);
752 		return -ENOMEM;
753 	}
754 	bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
755 	usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
756 				usb_sndbulkpipe(serial->dev, bEndpointAddress),
757 				port_priv->write_buffer,
758 				sizeof(port_priv->write_buffer),
759 				qt2_write_bulk_callback, port);
760 
761 	usb_set_serial_port_data(port, port_priv);
762 
763 	return 0;
764 }
765 
766 static int qt2_port_remove(struct usb_serial_port *port)
767 {
768 	struct qt2_port_private *port_priv;
769 
770 	port_priv = usb_get_serial_port_data(port);
771 	usb_free_urb(port_priv->write_urb);
772 	kfree(port_priv);
773 
774 	return 0;
775 }
776 
777 static int qt2_tiocmget(struct tty_struct *tty)
778 {
779 	struct usb_serial_port *port = tty->driver_data;
780 	struct usb_device *dev = port->serial->dev;
781 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
782 	u8 *d;
783 	int r;
784 
785 	d = kzalloc(2, GFP_KERNEL);
786 	if (!d)
787 		return -ENOMEM;
788 
789 	r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
790 	if (r < 0)
791 		goto mget_out;
792 
793 	r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
794 	if (r < 0)
795 		goto mget_out;
796 
797 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
798 	    (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
799 	    (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
800 	    (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
801 	    (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
802 	    (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
803 
804 mget_out:
805 	kfree(d);
806 	return r;
807 }
808 
809 static int qt2_tiocmset(struct tty_struct *tty,
810 			unsigned int set, unsigned int clear)
811 {
812 	struct qt2_port_private *port_priv;
813 
814 	port_priv = usb_get_serial_port_data(tty->driver_data);
815 	return update_mctrl(port_priv, set, clear);
816 }
817 
818 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
819 {
820 	struct usb_serial_port *port = tty->driver_data;
821 	struct qt2_port_private *port_priv;
822 	int status;
823 	u16 val;
824 
825 	port_priv = usb_get_serial_port_data(port);
826 
827 	val = (break_state == -1) ? 1 : 0;
828 
829 	status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
830 				 val, port_priv->device_port);
831 	if (status < 0)
832 		dev_warn(&port->dev,
833 			 "%s - failed to send control message: %i\n", __func__,
834 			 status);
835 }
836 
837 
838 
839 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
840 {
841 	struct usb_device *dev = port->serial->dev;
842 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
843 
844 	/* Disable flow control */
845 	if (!on) {
846 		if (qt2_setregister(dev, port_priv->device_port,
847 					   UART_MCR, 0) < 0)
848 			dev_warn(&port->dev, "error from flowcontrol urb\n");
849 	}
850 	/* drop RTS and DTR */
851 	if (on)
852 		update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
853 	else
854 		update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
855 }
856 
857 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
858 {
859 	struct qt2_port_private *port_priv;
860 	u8 newMSR = (u8) *ch;
861 	unsigned long flags;
862 
863 	port_priv = usb_get_serial_port_data(port);
864 
865 	spin_lock_irqsave(&port_priv->lock, flags);
866 	port_priv->shadowMSR = newMSR;
867 	spin_unlock_irqrestore(&port_priv->lock, flags);
868 
869 	if (newMSR & UART_MSR_ANY_DELTA) {
870 		/* update input line counters */
871 		if (newMSR & UART_MSR_DCTS)
872 			port->icount.cts++;
873 		if (newMSR & UART_MSR_DDSR)
874 			port->icount.dsr++;
875 		if (newMSR & UART_MSR_DDCD)
876 			port->icount.dcd++;
877 		if (newMSR & UART_MSR_TERI)
878 			port->icount.rng++;
879 
880 		wake_up_interruptible(&port->port.delta_msr_wait);
881 	}
882 }
883 
884 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
885 {
886 	struct qt2_port_private *port_priv;
887 	struct async_icount *icount;
888 	unsigned long flags;
889 	u8 newLSR = (u8) *ch;
890 
891 	port_priv = usb_get_serial_port_data(port);
892 
893 	if (newLSR & UART_LSR_BI)
894 		newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
895 
896 	spin_lock_irqsave(&port_priv->lock, flags);
897 	port_priv->shadowLSR = newLSR;
898 	spin_unlock_irqrestore(&port_priv->lock, flags);
899 
900 	icount = &port->icount;
901 
902 	if (newLSR & UART_LSR_BRK_ERROR_BITS) {
903 
904 		if (newLSR & UART_LSR_BI)
905 			icount->brk++;
906 
907 		if (newLSR & UART_LSR_OE)
908 			icount->overrun++;
909 
910 		if (newLSR & UART_LSR_PE)
911 			icount->parity++;
912 
913 		if (newLSR & UART_LSR_FE)
914 			icount->frame++;
915 	}
916 
917 }
918 
919 static int qt2_write_room(struct tty_struct *tty)
920 {
921 	struct usb_serial_port *port = tty->driver_data;
922 	struct qt2_port_private *port_priv;
923 	unsigned long flags = 0;
924 	int r;
925 
926 	port_priv = usb_get_serial_port_data(port);
927 
928 	spin_lock_irqsave(&port_priv->urb_lock, flags);
929 
930 	if (port_priv->urb_in_use)
931 		r = 0;
932 	else
933 		r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
934 
935 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
936 
937 	return r;
938 }
939 
940 static int qt2_write(struct tty_struct *tty,
941 		     struct usb_serial_port *port,
942 		     const unsigned char *buf, int count)
943 {
944 	struct qt2_port_private *port_priv;
945 	struct urb *write_urb;
946 	unsigned char *data;
947 	unsigned long flags;
948 	int status;
949 	int bytes_out = 0;
950 
951 	port_priv = usb_get_serial_port_data(port);
952 
953 	if (port_priv->write_urb == NULL) {
954 		dev_err(&port->dev, "%s - no output urb\n", __func__);
955 		return 0;
956 	}
957 	write_urb = port_priv->write_urb;
958 
959 	count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
960 
961 	data = write_urb->transfer_buffer;
962 	spin_lock_irqsave(&port_priv->urb_lock, flags);
963 	if (port_priv->urb_in_use == true) {
964 		dev_err(&port->dev, "qt2_write - urb is in use\n");
965 		goto write_out;
966 	}
967 
968 	*data++ = QT2_CONTROL_BYTE;
969 	*data++ = QT2_CONTROL_BYTE;
970 	*data++ = port_priv->device_port;
971 	put_unaligned_le16(count, data);
972 	data += 2;
973 	memcpy(data, buf, count);
974 
975 	write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
976 
977 	status = usb_submit_urb(write_urb, GFP_ATOMIC);
978 	if (status == 0) {
979 		port_priv->urb_in_use = true;
980 		bytes_out += count;
981 	}
982 
983 write_out:
984 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
985 	return bytes_out;
986 }
987 
988 
989 static struct usb_serial_driver qt2_device = {
990 	.driver = {
991 		.owner = THIS_MODULE,
992 		.name = "quatech-serial",
993 	},
994 	.description	     = DRIVER_DESC,
995 	.id_table	     = id_table,
996 	.open		     = qt2_open,
997 	.close		     = qt2_close,
998 	.write               = qt2_write,
999 	.write_room          = qt2_write_room,
1000 	.calc_num_ports      = qt2_calc_num_ports,
1001 	.attach              = qt2_attach,
1002 	.release             = qt2_release,
1003 	.disconnect          = qt2_disconnect,
1004 	.port_probe          = qt2_port_probe,
1005 	.port_remove         = qt2_port_remove,
1006 	.dtr_rts             = qt2_dtr_rts,
1007 	.break_ctl           = qt2_break_ctl,
1008 	.tiocmget            = qt2_tiocmget,
1009 	.tiocmset            = qt2_tiocmset,
1010 	.tiocmiwait          = usb_serial_generic_tiocmiwait,
1011 	.get_icount	     = usb_serial_generic_get_icount,
1012 	.ioctl               = qt2_ioctl,
1013 	.set_termios         = qt2_set_termios,
1014 };
1015 
1016 static struct usb_serial_driver *const serial_drivers[] = {
1017 	&qt2_device, NULL
1018 };
1019 
1020 module_usb_serial_driver(serial_drivers, id_table);
1021 
1022 MODULE_DESCRIPTION(DRIVER_DESC);
1023 MODULE_LICENSE("GPL");
1024