xref: /openbmc/linux/drivers/usb/serial/quatech2.c (revision 045f77ba)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * usb-serial driver for Quatech USB 2 devices
4  *
5  * Copyright (C) 2012 Bill Pemberton (wfp5p@virginia.edu)
6  *
7  *  These devices all have only 1 bulk in and 1 bulk out that is shared
8  *  for all serial ports.
9  *
10  */
11 
12 #include <asm/unaligned.h>
13 #include <linux/errno.h>
14 #include <linux/slab.h>
15 #include <linux/tty.h>
16 #include <linux/tty_driver.h>
17 #include <linux/tty_flip.h>
18 #include <linux/module.h>
19 #include <linux/serial.h>
20 #include <linux/usb.h>
21 #include <linux/usb/serial.h>
22 #include <linux/serial_reg.h>
23 #include <linux/uaccess.h>
24 
25 /* default urb timeout for usb operations */
26 #define QT2_USB_TIMEOUT USB_CTRL_SET_TIMEOUT
27 
28 #define QT_OPEN_CLOSE_CHANNEL       0xca
29 #define QT_SET_GET_DEVICE           0xc2
30 #define QT_SET_GET_REGISTER         0xc0
31 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
32 #define QT_SET_ATF                  0xcd
33 #define QT_TRANSFER_IN              0xc0
34 #define QT_HW_FLOW_CONTROL_MASK     0xc5
35 #define QT_SW_FLOW_CONTROL_MASK     0xc6
36 #define QT2_BREAK_CONTROL	    0xc8
37 #define QT2_GET_SET_UART            0xc1
38 #define QT2_FLUSH_DEVICE	    0xc4
39 #define QT2_GET_SET_QMCR            0xe1
40 #define QT2_QMCR_RS232              0x40
41 #define QT2_QMCR_RS422              0x10
42 
43 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
44 
45 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
46 
47 /* status bytes for the device */
48 #define QT2_CONTROL_BYTE    0x1b
49 #define QT2_LINE_STATUS     0x00  /* following 1 byte is line status */
50 #define QT2_MODEM_STATUS    0x01  /* following 1 byte is modem status */
51 #define QT2_XMIT_HOLD       0x02  /* following 2 bytes are ?? */
52 #define QT2_CHANGE_PORT     0x03  /* following 1 byte is port to change to */
53 #define QT2_REC_FLUSH       0x04  /* no following info */
54 #define QT2_XMIT_FLUSH      0x05  /* no following info */
55 #define QT2_CONTROL_ESCAPE  0xff  /* pass through previous 2 control bytes */
56 
57 #define  MAX_BAUD_RATE              921600
58 #define  DEFAULT_BAUD_RATE          9600
59 
60 #define QT2_READ_BUFFER_SIZE    512  /* size of read buffer */
61 #define QT2_WRITE_BUFFER_SIZE   512  /* size of write buffer */
62 #define QT2_WRITE_CONTROL_SIZE  5    /* control bytes used for a write */
63 
64 #define DRIVER_DESC "Quatech 2nd gen USB to Serial Driver"
65 
66 #define	USB_VENDOR_ID_QUATECH	0x061d
67 #define QUATECH_SSU2_100	0xC120	/* RS232 single port */
68 #define QUATECH_DSU2_100	0xC140	/* RS232 dual port */
69 #define QUATECH_DSU2_400	0xC150	/* RS232/422/485 dual port */
70 #define QUATECH_QSU2_100	0xC160	/* RS232 four port */
71 #define QUATECH_QSU2_400	0xC170	/* RS232/422/485 four port */
72 #define QUATECH_ESU2_100	0xC1A0	/* RS232 eight port */
73 #define QUATECH_ESU2_400	0xC180	/* RS232/422/485 eight port */
74 
75 struct qt2_device_detail {
76 	int product_id;
77 	int num_ports;
78 };
79 
80 #define QT_DETAILS(prod, ports)	\
81 	.product_id = (prod),   \
82 	.num_ports = (ports)
83 
84 static const struct qt2_device_detail qt2_device_details[] = {
85 	{QT_DETAILS(QUATECH_SSU2_100, 1)},
86 	{QT_DETAILS(QUATECH_DSU2_400, 2)},
87 	{QT_DETAILS(QUATECH_DSU2_100, 2)},
88 	{QT_DETAILS(QUATECH_QSU2_400, 4)},
89 	{QT_DETAILS(QUATECH_QSU2_100, 4)},
90 	{QT_DETAILS(QUATECH_ESU2_400, 8)},
91 	{QT_DETAILS(QUATECH_ESU2_100, 8)},
92 	{QT_DETAILS(0, 0)}	/* Terminating entry */
93 };
94 
95 static const struct usb_device_id id_table[] = {
96 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU2_100)},
97 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_100)},
98 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_400)},
99 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_100)},
100 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_400)},
101 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_100)},
102 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_400)},
103 	{}			/* Terminating entry */
104 };
105 MODULE_DEVICE_TABLE(usb, id_table);
106 
107 struct qt2_serial_private {
108 	unsigned char current_port;  /* current port for incoming data */
109 
110 	struct urb	*read_urb;   /* shared among all ports */
111 	char		*read_buffer;
112 };
113 
114 struct qt2_port_private {
115 	u8   device_port;
116 
117 	spinlock_t urb_lock;
118 	bool       urb_in_use;
119 	struct urb *write_urb;
120 	char       *write_buffer;
121 
122 	spinlock_t  lock;
123 	u8          shadowLSR;
124 	u8          shadowMSR;
125 
126 	struct usb_serial_port *port;
127 };
128 
129 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch);
130 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch);
131 static void qt2_write_bulk_callback(struct urb *urb);
132 static void qt2_read_bulk_callback(struct urb *urb);
133 
134 static void qt2_release(struct usb_serial *serial)
135 {
136 	struct qt2_serial_private *serial_priv;
137 
138 	serial_priv = usb_get_serial_data(serial);
139 
140 	usb_kill_urb(serial_priv->read_urb);
141 	usb_free_urb(serial_priv->read_urb);
142 	kfree(serial_priv->read_buffer);
143 	kfree(serial_priv);
144 }
145 
146 static inline int calc_baud_divisor(int baudrate)
147 {
148 	int divisor, rem;
149 
150 	divisor = MAX_BAUD_RATE / baudrate;
151 	rem = MAX_BAUD_RATE % baudrate;
152 	/* Round to nearest divisor */
153 	if (((rem * 2) >= baudrate) && (baudrate != 110))
154 		divisor++;
155 
156 	return divisor;
157 }
158 
159 static inline int qt2_set_port_config(struct usb_device *dev,
160 				      unsigned char port_number,
161 				      u16 baudrate, u16 lcr)
162 {
163 	int divisor = calc_baud_divisor(baudrate);
164 	u16 index = ((u16) (lcr << 8) | (u16) (port_number));
165 
166 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
167 			       QT2_GET_SET_UART, 0x40,
168 			       divisor, index, NULL, 0, QT2_USB_TIMEOUT);
169 }
170 
171 static inline int qt2_control_msg(struct usb_device *dev,
172 				  u8 request, u16 data, u16 index)
173 {
174 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
175 			       request, 0x40, data, index,
176 			       NULL, 0, QT2_USB_TIMEOUT);
177 }
178 
179 static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
180 {
181 	u16 x = ((u16) (data[1] << 8) | (u16) (data[0]));
182 
183 	return qt2_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
184 }
185 
186 
187 static inline int qt2_getregister(struct usb_device *dev,
188 				  u8 uart,
189 				  u8 reg,
190 				  u8 *data)
191 {
192 	int ret;
193 
194 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
195 			      QT_SET_GET_REGISTER, 0xc0, reg,
196 			      uart, data, sizeof(*data), QT2_USB_TIMEOUT);
197 	if (ret < (int)sizeof(*data)) {
198 		if (ret >= 0)
199 			ret = -EIO;
200 	}
201 
202 	return ret;
203 }
204 
205 static inline int qt2_setregister(struct usb_device *dev,
206 				  u8 uart, u8 reg, u16 data)
207 {
208 	u16 value = (data << 8) | reg;
209 
210 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
211 			       QT_SET_GET_REGISTER, 0x40, value, uart,
212 			       NULL, 0, QT2_USB_TIMEOUT);
213 }
214 
215 static inline int update_mctrl(struct qt2_port_private *port_priv,
216 			       unsigned int set, unsigned int clear)
217 {
218 	struct usb_serial_port *port = port_priv->port;
219 	struct usb_device *dev = port->serial->dev;
220 	unsigned urb_value;
221 	int status;
222 
223 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
224 		dev_dbg(&port->dev,
225 			"update_mctrl - DTR|RTS not being set|cleared\n");
226 		return 0;	/* no change */
227 	}
228 
229 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
230 	urb_value = 0;
231 	if (set & TIOCM_DTR)
232 		urb_value |= UART_MCR_DTR;
233 	if (set & TIOCM_RTS)
234 		urb_value |= UART_MCR_RTS;
235 
236 	status = qt2_setregister(dev, port_priv->device_port, UART_MCR,
237 				 urb_value);
238 	if (status < 0)
239 		dev_err(&port->dev,
240 			"update_mctrl - Error from MODEM_CTRL urb: %i\n",
241 			status);
242 	return status;
243 }
244 
245 static int qt2_calc_num_ports(struct usb_serial *serial,
246 					struct usb_serial_endpoints *epds)
247 {
248 	struct qt2_device_detail d;
249 	int i;
250 
251 	for (i = 0; d = qt2_device_details[i], d.product_id != 0; i++) {
252 		if (d.product_id == le16_to_cpu(serial->dev->descriptor.idProduct))
253 			return d.num_ports;
254 	}
255 
256 	/* we didn't recognize the device */
257 	dev_err(&serial->dev->dev,
258 		 "don't know the number of ports, assuming 1\n");
259 
260 	return 1;
261 }
262 
263 static void qt2_set_termios(struct tty_struct *tty,
264 			    struct usb_serial_port *port,
265 			    struct ktermios *old_termios)
266 {
267 	struct usb_device *dev = port->serial->dev;
268 	struct qt2_port_private *port_priv;
269 	struct ktermios *termios = &tty->termios;
270 	u16 baud;
271 	unsigned int cflag = termios->c_cflag;
272 	u16 new_lcr = 0;
273 	int status;
274 
275 	port_priv = usb_get_serial_port_data(port);
276 
277 	if (cflag & PARENB) {
278 		if (cflag & PARODD)
279 			new_lcr |= UART_LCR_PARITY;
280 		else
281 			new_lcr |= SERIAL_EVEN_PARITY;
282 	}
283 
284 	switch (cflag & CSIZE) {
285 	case CS5:
286 		new_lcr |= UART_LCR_WLEN5;
287 		break;
288 	case CS6:
289 		new_lcr |= UART_LCR_WLEN6;
290 		break;
291 	case CS7:
292 		new_lcr |= UART_LCR_WLEN7;
293 		break;
294 	default:
295 	case CS8:
296 		new_lcr |= UART_LCR_WLEN8;
297 		break;
298 	}
299 
300 	baud = tty_get_baud_rate(tty);
301 	if (!baud)
302 		baud = 9600;
303 
304 	status = qt2_set_port_config(dev, port_priv->device_port, baud,
305 				     new_lcr);
306 	if (status < 0)
307 		dev_err(&port->dev, "%s - qt2_set_port_config failed: %i\n",
308 			__func__, status);
309 
310 	if (cflag & CRTSCTS)
311 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
312 					 SERIAL_CRTSCTS,
313 					 port_priv->device_port);
314 	else
315 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
316 					 0, port_priv->device_port);
317 	if (status < 0)
318 		dev_err(&port->dev, "%s - set HW flow control failed: %i\n",
319 			__func__, status);
320 
321 	if (I_IXOFF(tty) || I_IXON(tty)) {
322 		u16 x = ((u16) (START_CHAR(tty) << 8) | (u16) (STOP_CHAR(tty)));
323 
324 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
325 					 x, port_priv->device_port);
326 	} else
327 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
328 					 0, port_priv->device_port);
329 
330 	if (status < 0)
331 		dev_err(&port->dev, "%s - set SW flow control failed: %i\n",
332 			__func__, status);
333 
334 }
335 
336 static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port)
337 {
338 	struct usb_serial *serial;
339 	struct qt2_port_private *port_priv;
340 	u8 *data;
341 	u16 device_port;
342 	int status;
343 	unsigned long flags;
344 
345 	device_port = port->port_number;
346 
347 	serial = port->serial;
348 
349 	port_priv = usb_get_serial_port_data(port);
350 
351 	/* set the port to RS232 mode */
352 	status = qt2_control_msg(serial->dev, QT2_GET_SET_QMCR,
353 				 QT2_QMCR_RS232, device_port);
354 	if (status < 0) {
355 		dev_err(&port->dev,
356 			"%s failed to set RS232 mode for port %i error %i\n",
357 			__func__, device_port, status);
358 		return status;
359 	}
360 
361 	data = kzalloc(2, GFP_KERNEL);
362 	if (!data)
363 		return -ENOMEM;
364 
365 	/* open the port */
366 	status = usb_control_msg(serial->dev,
367 				 usb_rcvctrlpipe(serial->dev, 0),
368 				 QT_OPEN_CLOSE_CHANNEL,
369 				 0xc0, 0,
370 				 device_port, data, 2, QT2_USB_TIMEOUT);
371 
372 	if (status < 2) {
373 		dev_err(&port->dev, "%s - open port failed %i\n", __func__,
374 			status);
375 		if (status >= 0)
376 			status = -EIO;
377 		kfree(data);
378 		return status;
379 	}
380 
381 	spin_lock_irqsave(&port_priv->lock, flags);
382 	port_priv->shadowLSR = data[0];
383 	port_priv->shadowMSR = data[1];
384 	spin_unlock_irqrestore(&port_priv->lock, flags);
385 
386 	kfree(data);
387 
388 	/* set to default speed and 8bit word size */
389 	status = qt2_set_port_config(serial->dev, device_port,
390 				     DEFAULT_BAUD_RATE, UART_LCR_WLEN8);
391 	if (status < 0) {
392 		dev_err(&port->dev, "%s - initial setup failed (%i)\n",
393 			__func__, 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 	int i;
411 
412 	serial = port->serial;
413 	port_priv = usb_get_serial_port_data(port);
414 
415 	usb_kill_urb(port_priv->write_urb);
416 
417 	/* flush the port transmit buffer */
418 	i = usb_control_msg(serial->dev,
419 			    usb_rcvctrlpipe(serial->dev, 0),
420 			    QT2_FLUSH_DEVICE, 0x40, 1,
421 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
422 
423 	if (i < 0)
424 		dev_err(&port->dev, "%s - transmit buffer flush failed: %i\n",
425 			__func__, i);
426 
427 	/* flush the port receive buffer */
428 	i = usb_control_msg(serial->dev,
429 			    usb_rcvctrlpipe(serial->dev, 0),
430 			    QT2_FLUSH_DEVICE, 0x40, 0,
431 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
432 
433 	if (i < 0)
434 		dev_err(&port->dev, "%s - receive buffer flush failed: %i\n",
435 			__func__, i);
436 
437 	/* close the port */
438 	i = usb_control_msg(serial->dev,
439 			    usb_sndctrlpipe(serial->dev, 0),
440 			    QT_OPEN_CLOSE_CHANNEL,
441 			    0x40, 0,
442 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
443 
444 	if (i < 0)
445 		dev_err(&port->dev, "%s - close port failed %i\n",
446 			__func__, i);
447 }
448 
449 static void qt2_disconnect(struct usb_serial *serial)
450 {
451 	struct qt2_serial_private *serial_priv = usb_get_serial_data(serial);
452 
453 	usb_kill_urb(serial_priv->read_urb);
454 }
455 
456 static int get_serial_info(struct usb_serial_port *port,
457 			   struct serial_struct __user *retinfo)
458 {
459 	struct serial_struct tmp;
460 
461 	memset(&tmp, 0, sizeof(tmp));
462 	tmp.line		= port->minor;
463 	tmp.port		= 0;
464 	tmp.irq			= 0;
465 	tmp.xmit_fifo_size	= port->bulk_out_size;
466 	tmp.baud_base		= 9600;
467 	tmp.close_delay		= 5*HZ;
468 	tmp.closing_wait	= 30*HZ;
469 
470 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
471 		return -EFAULT;
472 	return 0;
473 }
474 
475 static int qt2_ioctl(struct tty_struct *tty,
476 		     unsigned int cmd, unsigned long arg)
477 {
478 	struct usb_serial_port *port = tty->driver_data;
479 
480 	switch (cmd) {
481 	case TIOCGSERIAL:
482 		return get_serial_info(port,
483 				       (struct serial_struct __user *)arg);
484 	default:
485 		break;
486 	}
487 
488 	return -ENOIOCTLCMD;
489 }
490 
491 static void qt2_process_status(struct usb_serial_port *port, unsigned char *ch)
492 {
493 	switch (*ch) {
494 	case QT2_LINE_STATUS:
495 		qt2_update_lsr(port, ch + 1);
496 		break;
497 	case QT2_MODEM_STATUS:
498 		qt2_update_msr(port, ch + 1);
499 		break;
500 	}
501 }
502 
503 /* not needed, kept to document functionality */
504 static void qt2_process_xmit_empty(struct usb_serial_port *port,
505 				   unsigned char *ch)
506 {
507 	int bytes_written;
508 
509 	bytes_written = (int)(*ch) + (int)(*(ch + 1) << 4);
510 }
511 
512 /* not needed, kept to document functionality */
513 static void qt2_process_flush(struct usb_serial_port *port, unsigned char *ch)
514 {
515 	return;
516 }
517 
518 static void qt2_process_read_urb(struct urb *urb)
519 {
520 	struct usb_serial *serial;
521 	struct qt2_serial_private *serial_priv;
522 	struct usb_serial_port *port;
523 	struct qt2_port_private *port_priv;
524 	bool escapeflag;
525 	unsigned char *ch;
526 	int i;
527 	unsigned char newport;
528 	int len = urb->actual_length;
529 
530 	if (!len)
531 		return;
532 
533 	ch = urb->transfer_buffer;
534 	serial = urb->context;
535 	serial_priv = usb_get_serial_data(serial);
536 	port = serial->port[serial_priv->current_port];
537 	port_priv = usb_get_serial_port_data(port);
538 
539 	for (i = 0; i < urb->actual_length; i++) {
540 		ch = (unsigned char *)urb->transfer_buffer + i;
541 		if ((i <= (len - 3)) &&
542 		    (*ch == QT2_CONTROL_BYTE) &&
543 		    (*(ch + 1) == QT2_CONTROL_BYTE)) {
544 			escapeflag = false;
545 			switch (*(ch + 2)) {
546 			case QT2_LINE_STATUS:
547 			case QT2_MODEM_STATUS:
548 				if (i > (len - 4)) {
549 					dev_warn(&port->dev,
550 						 "%s - status message too short\n",
551 						__func__);
552 					break;
553 				}
554 				qt2_process_status(port, ch + 2);
555 				i += 3;
556 				escapeflag = true;
557 				break;
558 			case QT2_XMIT_HOLD:
559 				if (i > (len - 5)) {
560 					dev_warn(&port->dev,
561 						 "%s - xmit_empty message too short\n",
562 						 __func__);
563 					break;
564 				}
565 				qt2_process_xmit_empty(port, ch + 3);
566 				i += 4;
567 				escapeflag = true;
568 				break;
569 			case QT2_CHANGE_PORT:
570 				if (i > (len - 4)) {
571 					dev_warn(&port->dev,
572 						 "%s - change_port message too short\n",
573 						 __func__);
574 					break;
575 				}
576 				tty_flip_buffer_push(&port->port);
577 
578 				newport = *(ch + 3);
579 
580 				if (newport > serial->num_ports) {
581 					dev_err(&port->dev,
582 						"%s - port change to invalid port: %i\n",
583 						__func__, newport);
584 					break;
585 				}
586 
587 				serial_priv->current_port = newport;
588 				port = serial->port[serial_priv->current_port];
589 				port_priv = usb_get_serial_port_data(port);
590 				i += 3;
591 				escapeflag = true;
592 				break;
593 			case QT2_REC_FLUSH:
594 			case QT2_XMIT_FLUSH:
595 				qt2_process_flush(port, ch + 2);
596 				i += 2;
597 				escapeflag = true;
598 				break;
599 			case QT2_CONTROL_ESCAPE:
600 				tty_insert_flip_string(&port->port, ch, 2);
601 				i += 2;
602 				escapeflag = true;
603 				break;
604 			default:
605 				dev_warn(&port->dev,
606 					 "%s - unsupported command %i\n",
607 					 __func__, *(ch + 2));
608 				break;
609 			}
610 			if (escapeflag)
611 				continue;
612 		}
613 
614 		tty_insert_flip_char(&port->port, *ch, TTY_NORMAL);
615 	}
616 
617 	tty_flip_buffer_push(&port->port);
618 }
619 
620 static void qt2_write_bulk_callback(struct urb *urb)
621 {
622 	struct usb_serial_port *port;
623 	struct qt2_port_private *port_priv;
624 	unsigned long flags;
625 
626 	port = urb->context;
627 	port_priv = usb_get_serial_port_data(port);
628 
629 	spin_lock_irqsave(&port_priv->urb_lock, flags);
630 
631 	port_priv->urb_in_use = false;
632 	usb_serial_port_softint(port);
633 
634 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
635 
636 }
637 
638 static void qt2_read_bulk_callback(struct urb *urb)
639 {
640 	struct usb_serial *serial = urb->context;
641 	int status;
642 
643 	if (urb->status) {
644 		dev_warn(&serial->dev->dev,
645 			 "%s - non-zero urb status: %i\n", __func__,
646 			 urb->status);
647 		return;
648 	}
649 
650 	qt2_process_read_urb(urb);
651 
652 	status = usb_submit_urb(urb, GFP_ATOMIC);
653 	if (status != 0)
654 		dev_err(&serial->dev->dev,
655 			"%s - resubmit read urb failed: %i\n",
656 			__func__, status);
657 }
658 
659 static int qt2_setup_urbs(struct usb_serial *serial)
660 {
661 	struct usb_serial_port *port0;
662 	struct qt2_serial_private *serial_priv;
663 	int status;
664 
665 	port0 = serial->port[0];
666 
667 	serial_priv = usb_get_serial_data(serial);
668 	serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
669 	if (!serial_priv->read_urb)
670 		return -ENOMEM;
671 
672 	usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
673 			  usb_rcvbulkpipe(serial->dev,
674 					  port0->bulk_in_endpointAddress),
675 			  serial_priv->read_buffer,
676 			  QT2_READ_BUFFER_SIZE,
677 			  qt2_read_bulk_callback, serial);
678 
679 	status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
680 	if (status != 0) {
681 		dev_err(&serial->dev->dev,
682 			"%s - submit read urb failed %i\n", __func__, status);
683 		usb_free_urb(serial_priv->read_urb);
684 		return status;
685 	}
686 
687 	return 0;
688 }
689 
690 static int qt2_attach(struct usb_serial *serial)
691 {
692 	struct qt2_serial_private *serial_priv;
693 	int status;
694 
695 	/* power on unit */
696 	status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
697 				 0xc2, 0x40, 0x8000, 0, NULL, 0,
698 				 QT2_USB_TIMEOUT);
699 	if (status < 0) {
700 		dev_err(&serial->dev->dev,
701 			"%s - failed to power on unit: %i\n", __func__, status);
702 		return status;
703 	}
704 
705 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
706 	if (!serial_priv)
707 		return -ENOMEM;
708 
709 	serial_priv->read_buffer = kmalloc(QT2_READ_BUFFER_SIZE, GFP_KERNEL);
710 	if (!serial_priv->read_buffer) {
711 		status = -ENOMEM;
712 		goto err_buf;
713 	}
714 
715 	usb_set_serial_data(serial, serial_priv);
716 
717 	status = qt2_setup_urbs(serial);
718 	if (status != 0)
719 		goto attach_failed;
720 
721 	return 0;
722 
723 attach_failed:
724 	kfree(serial_priv->read_buffer);
725 err_buf:
726 	kfree(serial_priv);
727 	return status;
728 }
729 
730 static int qt2_port_probe(struct usb_serial_port *port)
731 {
732 	struct usb_serial *serial = port->serial;
733 	struct qt2_port_private *port_priv;
734 	u8 bEndpointAddress;
735 
736 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
737 	if (!port_priv)
738 		return -ENOMEM;
739 
740 	spin_lock_init(&port_priv->lock);
741 	spin_lock_init(&port_priv->urb_lock);
742 	port_priv->port = port;
743 
744 	port_priv->write_buffer = kmalloc(QT2_WRITE_BUFFER_SIZE, GFP_KERNEL);
745 	if (!port_priv->write_buffer)
746 		goto err_buf;
747 
748 	port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
749 	if (!port_priv->write_urb)
750 		goto err_urb;
751 
752 	bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
753 	usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
754 				usb_sndbulkpipe(serial->dev, bEndpointAddress),
755 				port_priv->write_buffer,
756 				QT2_WRITE_BUFFER_SIZE,
757 				qt2_write_bulk_callback, port);
758 
759 	usb_set_serial_port_data(port, port_priv);
760 
761 	return 0;
762 err_urb:
763 	kfree(port_priv->write_buffer);
764 err_buf:
765 	kfree(port_priv);
766 	return -ENOMEM;
767 }
768 
769 static int qt2_port_remove(struct usb_serial_port *port)
770 {
771 	struct qt2_port_private *port_priv;
772 
773 	port_priv = usb_get_serial_port_data(port);
774 	usb_free_urb(port_priv->write_urb);
775 	kfree(port_priv->write_buffer);
776 	kfree(port_priv);
777 
778 	return 0;
779 }
780 
781 static int qt2_tiocmget(struct tty_struct *tty)
782 {
783 	struct usb_serial_port *port = tty->driver_data;
784 	struct usb_device *dev = port->serial->dev;
785 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
786 	u8 *d;
787 	int r;
788 
789 	d = kzalloc(2, GFP_KERNEL);
790 	if (!d)
791 		return -ENOMEM;
792 
793 	r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
794 	if (r < 0)
795 		goto mget_out;
796 
797 	r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
798 	if (r < 0)
799 		goto mget_out;
800 
801 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
802 	    (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
803 	    (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
804 	    (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
805 	    (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
806 	    (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
807 
808 mget_out:
809 	kfree(d);
810 	return r;
811 }
812 
813 static int qt2_tiocmset(struct tty_struct *tty,
814 			unsigned int set, unsigned int clear)
815 {
816 	struct qt2_port_private *port_priv;
817 
818 	port_priv = usb_get_serial_port_data(tty->driver_data);
819 	return update_mctrl(port_priv, set, clear);
820 }
821 
822 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
823 {
824 	struct usb_serial_port *port = tty->driver_data;
825 	struct qt2_port_private *port_priv;
826 	int status;
827 	u16 val;
828 
829 	port_priv = usb_get_serial_port_data(port);
830 
831 	val = (break_state == -1) ? 1 : 0;
832 
833 	status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
834 				 val, port_priv->device_port);
835 	if (status < 0)
836 		dev_warn(&port->dev,
837 			 "%s - failed to send control message: %i\n", __func__,
838 			 status);
839 }
840 
841 
842 
843 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
844 {
845 	struct usb_device *dev = port->serial->dev;
846 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
847 
848 	/* Disable flow control */
849 	if (!on) {
850 		if (qt2_setregister(dev, port_priv->device_port,
851 					   UART_MCR, 0) < 0)
852 			dev_warn(&port->dev, "error from flowcontrol urb\n");
853 	}
854 	/* drop RTS and DTR */
855 	if (on)
856 		update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
857 	else
858 		update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
859 }
860 
861 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
862 {
863 	struct qt2_port_private *port_priv;
864 	u8 newMSR = (u8) *ch;
865 	unsigned long flags;
866 
867 	port_priv = usb_get_serial_port_data(port);
868 
869 	spin_lock_irqsave(&port_priv->lock, flags);
870 	port_priv->shadowMSR = newMSR;
871 	spin_unlock_irqrestore(&port_priv->lock, flags);
872 
873 	if (newMSR & UART_MSR_ANY_DELTA) {
874 		/* update input line counters */
875 		if (newMSR & UART_MSR_DCTS)
876 			port->icount.cts++;
877 		if (newMSR & UART_MSR_DDSR)
878 			port->icount.dsr++;
879 		if (newMSR & UART_MSR_DDCD)
880 			port->icount.dcd++;
881 		if (newMSR & UART_MSR_TERI)
882 			port->icount.rng++;
883 
884 		wake_up_interruptible(&port->port.delta_msr_wait);
885 	}
886 }
887 
888 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
889 {
890 	struct qt2_port_private *port_priv;
891 	struct async_icount *icount;
892 	unsigned long flags;
893 	u8 newLSR = (u8) *ch;
894 
895 	port_priv = usb_get_serial_port_data(port);
896 
897 	if (newLSR & UART_LSR_BI)
898 		newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
899 
900 	spin_lock_irqsave(&port_priv->lock, flags);
901 	port_priv->shadowLSR = newLSR;
902 	spin_unlock_irqrestore(&port_priv->lock, flags);
903 
904 	icount = &port->icount;
905 
906 	if (newLSR & UART_LSR_BRK_ERROR_BITS) {
907 
908 		if (newLSR & UART_LSR_BI)
909 			icount->brk++;
910 
911 		if (newLSR & UART_LSR_OE)
912 			icount->overrun++;
913 
914 		if (newLSR & UART_LSR_PE)
915 			icount->parity++;
916 
917 		if (newLSR & UART_LSR_FE)
918 			icount->frame++;
919 	}
920 
921 }
922 
923 static int qt2_write_room(struct tty_struct *tty)
924 {
925 	struct usb_serial_port *port = tty->driver_data;
926 	struct qt2_port_private *port_priv;
927 	unsigned long flags = 0;
928 	int r;
929 
930 	port_priv = usb_get_serial_port_data(port);
931 
932 	spin_lock_irqsave(&port_priv->urb_lock, flags);
933 
934 	if (port_priv->urb_in_use)
935 		r = 0;
936 	else
937 		r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
938 
939 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
940 
941 	return r;
942 }
943 
944 static int qt2_write(struct tty_struct *tty,
945 		     struct usb_serial_port *port,
946 		     const unsigned char *buf, int count)
947 {
948 	struct qt2_port_private *port_priv;
949 	struct urb *write_urb;
950 	unsigned char *data;
951 	unsigned long flags;
952 	int status;
953 	int bytes_out = 0;
954 
955 	port_priv = usb_get_serial_port_data(port);
956 
957 	if (port_priv->write_urb == NULL) {
958 		dev_err(&port->dev, "%s - no output urb\n", __func__);
959 		return 0;
960 	}
961 	write_urb = port_priv->write_urb;
962 
963 	count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
964 
965 	data = write_urb->transfer_buffer;
966 	spin_lock_irqsave(&port_priv->urb_lock, flags);
967 	if (port_priv->urb_in_use) {
968 		dev_err(&port->dev, "qt2_write - urb is in use\n");
969 		goto write_out;
970 	}
971 
972 	*data++ = QT2_CONTROL_BYTE;
973 	*data++ = QT2_CONTROL_BYTE;
974 	*data++ = port_priv->device_port;
975 	put_unaligned_le16(count, data);
976 	data += 2;
977 	memcpy(data, buf, count);
978 
979 	write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
980 
981 	status = usb_submit_urb(write_urb, GFP_ATOMIC);
982 	if (status == 0) {
983 		port_priv->urb_in_use = true;
984 		bytes_out += count;
985 	}
986 
987 write_out:
988 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
989 	return bytes_out;
990 }
991 
992 
993 static struct usb_serial_driver qt2_device = {
994 	.driver = {
995 		.owner = THIS_MODULE,
996 		.name = "quatech-serial",
997 	},
998 	.description	     = DRIVER_DESC,
999 	.id_table	     = id_table,
1000 	.open		     = qt2_open,
1001 	.close		     = qt2_close,
1002 	.write               = qt2_write,
1003 	.write_room          = qt2_write_room,
1004 	.calc_num_ports      = qt2_calc_num_ports,
1005 	.attach              = qt2_attach,
1006 	.release             = qt2_release,
1007 	.disconnect          = qt2_disconnect,
1008 	.port_probe          = qt2_port_probe,
1009 	.port_remove         = qt2_port_remove,
1010 	.dtr_rts             = qt2_dtr_rts,
1011 	.break_ctl           = qt2_break_ctl,
1012 	.tiocmget            = qt2_tiocmget,
1013 	.tiocmset            = qt2_tiocmset,
1014 	.tiocmiwait          = usb_serial_generic_tiocmiwait,
1015 	.get_icount	     = usb_serial_generic_get_icount,
1016 	.ioctl               = qt2_ioctl,
1017 	.set_termios         = qt2_set_termios,
1018 };
1019 
1020 static struct usb_serial_driver *const serial_drivers[] = {
1021 	&qt2_device, NULL
1022 };
1023 
1024 module_usb_serial_driver(serial_drivers, id_table);
1025 
1026 MODULE_DESCRIPTION(DRIVER_DESC);
1027 MODULE_LICENSE("GPL v2");
1028