xref: /linux/drivers/usb/serial/quatech2.c (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
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 static bool debug;
31 
32 /* default urb timeout for usb operations */
33 #define QT2_USB_TIMEOUT USB_CTRL_SET_TIMEOUT
34 
35 #define QT_OPEN_CLOSE_CHANNEL       0xca
36 #define QT_SET_GET_DEVICE           0xc2
37 #define QT_SET_GET_REGISTER         0xc0
38 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
39 #define QT_SET_ATF                  0xcd
40 #define QT_TRANSFER_IN              0xc0
41 #define QT_HW_FLOW_CONTROL_MASK     0xc5
42 #define QT_SW_FLOW_CONTROL_MASK     0xc6
43 #define QT2_BREAK_CONTROL	    0xc8
44 #define QT2_GET_SET_UART            0xc1
45 #define QT2_FLUSH_DEVICE	    0xc4
46 #define QT2_GET_SET_QMCR            0xe1
47 #define QT2_QMCR_RS232              0x40
48 #define QT2_QMCR_RS422              0x10
49 
50 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
51 
52 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
53 
54 /* status bytes for the device */
55 #define QT2_CONTROL_BYTE    0x1b
56 #define QT2_LINE_STATUS     0x00  /* following 1 byte is line status */
57 #define QT2_MODEM_STATUS    0x01  /* following 1 byte is modem status */
58 #define QT2_XMIT_HOLD       0x02  /* following 2 bytes are ?? */
59 #define QT2_CHANGE_PORT     0x03  /* following 1 byte is port to change to */
60 #define QT2_REC_FLUSH       0x04  /* no following info */
61 #define QT2_XMIT_FLUSH      0x05  /* no following info */
62 #define QT2_CONTROL_ESCAPE  0xff  /* pass through previous 2 control bytes */
63 
64 #define  MAX_BAUD_RATE              921600
65 #define  DEFAULT_BAUD_RATE          9600
66 
67 #define QT2_WRITE_BUFFER_SIZE   512  /* size of write buffer */
68 #define QT2_WRITE_CONTROL_SIZE  5    /* control bytes used for a write */
69 
70 /* Version Information */
71 #define DRIVER_VERSION "v0.1"
72 #define DRIVER_DESC "Quatech 2nd gen USB to Serial Driver"
73 
74 #define	USB_VENDOR_ID_QUATECH	0x061d
75 #define QUATECH_SSU2_100	0xC120	/* RS232 single port */
76 #define QUATECH_DSU2_100	0xC140	/* RS232 dual port */
77 #define QUATECH_DSU2_400	0xC150	/* RS232/422/485 dual port */
78 #define QUATECH_QSU2_100	0xC160	/* RS232 four port */
79 #define QUATECH_QSU2_400	0xC170	/* RS232/422/485 four port */
80 #define QUATECH_ESU2_100	0xC1A0	/* RS232 eight port */
81 #define QUATECH_ESU2_400	0xC180	/* RS232/422/485 eight port */
82 
83 struct qt2_device_detail {
84 	int product_id;
85 	int num_ports;
86 };
87 
88 #define QT_DETAILS(prod, ports)	\
89 	.product_id = (prod),   \
90 	.num_ports = (ports)
91 
92 static const struct qt2_device_detail qt2_device_details[] = {
93 	{QT_DETAILS(QUATECH_SSU2_100, 1)},
94 	{QT_DETAILS(QUATECH_DSU2_400, 2)},
95 	{QT_DETAILS(QUATECH_DSU2_100, 2)},
96 	{QT_DETAILS(QUATECH_QSU2_400, 4)},
97 	{QT_DETAILS(QUATECH_QSU2_100, 4)},
98 	{QT_DETAILS(QUATECH_ESU2_400, 8)},
99 	{QT_DETAILS(QUATECH_ESU2_100, 8)},
100 	{QT_DETAILS(0, 0)}	/* Terminating entry */
101 };
102 
103 static const struct usb_device_id id_table[] = {
104 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU2_100)},
105 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_100)},
106 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_400)},
107 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_100)},
108 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_400)},
109 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_100)},
110 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_400)},
111 	{}			/* Terminating entry */
112 };
113 MODULE_DEVICE_TABLE(usb, id_table);
114 
115 struct qt2_serial_private {
116 	unsigned char current_port;  /* current port for incoming data */
117 
118 	struct urb	*read_urb;   /* shared among all ports */
119 	char		read_buffer[512];
120 };
121 
122 struct qt2_port_private {
123 	bool is_open;
124 	u8   device_port;
125 
126 	spinlock_t urb_lock;
127 	bool       urb_in_use;
128 	struct urb *write_urb;
129 	char       write_buffer[QT2_WRITE_BUFFER_SIZE];
130 
131 	spinlock_t  lock;
132 	u8          shadowLSR;
133 	u8          shadowMSR;
134 
135 	wait_queue_head_t   delta_msr_wait; /* Used for TIOCMIWAIT */
136 	struct async_icount icount;
137 
138 	struct usb_serial_port *port;
139 };
140 
141 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch);
142 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch);
143 static void qt2_write_bulk_callback(struct urb *urb);
144 static void qt2_read_bulk_callback(struct urb *urb);
145 
146 static void qt2_release(struct usb_serial *serial)
147 {
148 	int i;
149 
150 	kfree(usb_get_serial_data(serial));
151 
152 	for (i = 0; i < serial->num_ports; i++)
153 		kfree(usb_get_serial_port_data(serial->port[i]));
154 }
155 
156 static inline int calc_baud_divisor(int baudrate)
157 {
158 	int divisor, rem;
159 
160 	divisor = MAX_BAUD_RATE / baudrate;
161 	rem = MAX_BAUD_RATE % baudrate;
162 	/* Round to nearest divisor */
163 	if (((rem * 2) >= baudrate) && (baudrate != 110))
164 		divisor++;
165 
166 	return divisor;
167 }
168 
169 static inline int qt2_set_port_config(struct usb_device *dev,
170 				      unsigned char port_number,
171 				      u16 baudrate, u16 lcr)
172 {
173 	int divisor = calc_baud_divisor(baudrate);
174 	u16 index = ((u16) (lcr << 8) | (u16) (port_number));
175 
176 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
177 			       QT2_GET_SET_UART, 0x40,
178 			       divisor, index, NULL, 0, QT2_USB_TIMEOUT);
179 }
180 
181 static inline int qt2_control_msg(struct usb_device *dev,
182 				  u8 request, u16 data, u16 index)
183 {
184 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
185 			       request, 0x40, data, index,
186 			       NULL, 0, QT2_USB_TIMEOUT);
187 }
188 
189 static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
190 {
191 	u16 x = ((u16) (data[1] << 8) | (u16) (data[0]));
192 
193 	return qt2_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
194 }
195 
196 
197 static inline int qt2_getdevice(struct usb_device *dev, u8 *data)
198 {
199 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
200 			       QT_SET_GET_DEVICE, 0xc0, 0, 0,
201 			       data, 3, QT2_USB_TIMEOUT);
202 }
203 
204 static inline int qt2_getregister(struct usb_device *dev,
205 				  u8 uart,
206 				  u8 reg,
207 				  u8 *data)
208 {
209 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
210 			       QT_SET_GET_REGISTER, 0xc0, reg,
211 			       uart, data, sizeof(*data), QT2_USB_TIMEOUT);
212 
213 }
214 
215 static inline int qt2_setregister(struct usb_device *dev,
216 				  u8 uart, u8 reg, u16 data)
217 {
218 	u16 value = (data << 8) | reg;
219 
220 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
221 			       QT_SET_GET_REGISTER, 0x40, value, uart,
222 			       NULL, 0, QT2_USB_TIMEOUT);
223 }
224 
225 static inline int update_mctrl(struct qt2_port_private *port_priv,
226 			       unsigned int set, unsigned int clear)
227 {
228 	struct usb_serial_port *port = port_priv->port;
229 	struct usb_device *dev = port->serial->dev;
230 	unsigned urb_value;
231 	int status;
232 
233 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
234 		dev_dbg(&port->dev,
235 			"update_mctrl - DTR|RTS not being set|cleared\n");
236 		return 0;	/* no change */
237 	}
238 
239 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
240 	urb_value = 0;
241 	if (set & TIOCM_DTR)
242 		urb_value |= UART_MCR_DTR;
243 	if (set & TIOCM_RTS)
244 		urb_value |= UART_MCR_RTS;
245 
246 	status = qt2_setregister(dev, port_priv->device_port, UART_MCR,
247 				 urb_value);
248 	if (status < 0)
249 		dev_err(&port->dev,
250 			"update_mctrl - Error from MODEM_CTRL urb: %i\n",
251 			status);
252 	return status;
253 }
254 
255 static int qt2_calc_num_ports(struct usb_serial *serial)
256 {
257 	struct qt2_device_detail d;
258 	int i;
259 
260 	for (i = 0; d = qt2_device_details[i], d.product_id != 0; i++) {
261 		if (d.product_id == le16_to_cpu(serial->dev->descriptor.idProduct))
262 			return d.num_ports;
263 	}
264 
265 	/* we didn't recognize the device */
266 	dev_err(&serial->dev->dev,
267 		 "don't know the number of ports, assuming 1\n");
268 
269 	return 1;
270 }
271 
272 static void qt2_set_termios(struct tty_struct *tty,
273 			    struct usb_serial_port *port,
274 			    struct ktermios *old_termios)
275 {
276 	struct usb_device *dev = port->serial->dev;
277 	struct qt2_port_private *port_priv;
278 	struct ktermios *termios = tty->termios;
279 	u16 baud;
280 	unsigned int cflag = termios->c_cflag;
281 	u16 new_lcr = 0;
282 	int status;
283 
284 	port_priv = usb_get_serial_port_data(port);
285 
286 	if (cflag & PARENB) {
287 		if (cflag & PARODD)
288 			new_lcr |= UART_LCR_PARITY;
289 		else
290 			new_lcr |= SERIAL_EVEN_PARITY;
291 	}
292 
293 	switch (cflag & CSIZE) {
294 	case CS5:
295 		new_lcr |= UART_LCR_WLEN5;
296 		break;
297 	case CS6:
298 		new_lcr |= UART_LCR_WLEN6;
299 		break;
300 	case CS7:
301 		new_lcr |= UART_LCR_WLEN7;
302 		break;
303 	default:
304 	case CS8:
305 		new_lcr |= UART_LCR_WLEN8;
306 		break;
307 	}
308 
309 	baud = tty_get_baud_rate(tty);
310 	if (!baud)
311 		baud = 9600;
312 
313 	status = qt2_set_port_config(dev, port_priv->device_port, baud,
314 				     new_lcr);
315 	if (status < 0)
316 		dev_err(&port->dev, "%s - qt2_set_port_config failed: %i\n",
317 			__func__, status);
318 
319 	if (cflag & CRTSCTS)
320 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
321 					 SERIAL_CRTSCTS,
322 					 port_priv->device_port);
323 	else
324 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
325 					 0, port_priv->device_port);
326 	if (status < 0)
327 		dev_err(&port->dev, "%s - set HW flow control failed: %i\n",
328 			__func__, status);
329 
330 	if (I_IXOFF(tty) || I_IXON(tty)) {
331 		u16 x = ((u16) (START_CHAR(tty) << 8) | (u16) (STOP_CHAR(tty)));
332 
333 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
334 					 x, port_priv->device_port);
335 	} else
336 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
337 					 0, port_priv->device_port);
338 
339 	if (status < 0)
340 		dev_err(&port->dev, "%s - set SW flow control failed: %i\n",
341 			__func__, status);
342 
343 }
344 
345 static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port)
346 {
347 	struct usb_serial *serial;
348 	struct qt2_port_private *port_priv;
349 	u8 *data;
350 	u16 device_port;
351 	int status;
352 	unsigned long flags;
353 
354 	device_port = (u16) (port->number - port->serial->minor);
355 
356 	serial = port->serial;
357 
358 	port_priv = usb_get_serial_port_data(port);
359 
360 	/* set the port to RS232 mode */
361 	status = qt2_control_msg(serial->dev, QT2_GET_SET_QMCR,
362 				 QT2_QMCR_RS232, device_port);
363 	if (status < 0) {
364 		dev_err(&port->dev,
365 			"%s failed to set RS232 mode for port %i error %i\n",
366 			__func__, device_port, status);
367 		return status;
368 	}
369 
370 	data = kzalloc(2, GFP_KERNEL);
371 	if (!data)
372 		return -ENOMEM;
373 
374 	/* open the port */
375 	status = usb_control_msg(serial->dev,
376 				 usb_rcvctrlpipe(serial->dev, 0),
377 				 QT_OPEN_CLOSE_CHANNEL,
378 				 0xc0, 0,
379 				 device_port, data, 2, QT2_USB_TIMEOUT);
380 
381 	if (status < 0) {
382 		dev_err(&port->dev, "%s - open port failed %i", __func__,
383 			status);
384 		kfree(data);
385 		return status;
386 	}
387 
388 	spin_lock_irqsave(&port_priv->lock, flags);
389 	port_priv->shadowLSR = data[0];
390 	port_priv->shadowMSR = data[1];
391 	spin_unlock_irqrestore(&port_priv->lock, flags);
392 
393 	kfree(data);
394 
395 	/* set to default speed and 8bit word size */
396 	status = qt2_set_port_config(serial->dev, device_port,
397 				     DEFAULT_BAUD_RATE, UART_LCR_WLEN8);
398 	if (status < 0) {
399 		dev_err(&port->dev,
400 			"%s - initial setup failed for port %i (%i)\n",
401 			__func__, port->number, device_port);
402 		return status;
403 	}
404 
405 	port_priv->is_open = true;
406 	port_priv->device_port = (u8) device_port;
407 
408 	if (tty)
409 		qt2_set_termios(tty, port, tty->termios);
410 
411 	return 0;
412 
413 }
414 
415 static void qt2_close(struct usb_serial_port *port)
416 {
417 	struct usb_serial *serial;
418 	struct qt2_port_private *port_priv;
419 	unsigned long flags;
420 	int i;
421 
422 	serial = port->serial;
423 	port_priv = usb_get_serial_port_data(port);
424 
425 	port_priv->is_open = false;
426 
427 	spin_lock_irqsave(&port_priv->urb_lock, flags);
428 	if (port_priv->write_urb->status == -EINPROGRESS)
429 		usb_kill_urb(port_priv->write_urb);
430 	port_priv->urb_in_use = false;
431 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
432 
433 	/* flush the port transmit buffer */
434 	i = usb_control_msg(serial->dev,
435 			    usb_rcvctrlpipe(serial->dev, 0),
436 			    QT2_FLUSH_DEVICE, 0x40, 1,
437 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
438 
439 	if (i < 0)
440 		dev_err(&port->dev, "%s - transmit buffer flush failed: %i\n",
441 			__func__, i);
442 
443 	/* flush the port receive buffer */
444 	i = usb_control_msg(serial->dev,
445 			    usb_rcvctrlpipe(serial->dev, 0),
446 			    QT2_FLUSH_DEVICE, 0x40, 0,
447 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
448 
449 	if (i < 0)
450 		dev_err(&port->dev, "%s - receive buffer flush failed: %i\n",
451 			__func__, i);
452 
453 	/* close the port */
454 	i = usb_control_msg(serial->dev,
455 			    usb_sndctrlpipe(serial->dev, 0),
456 			    QT_OPEN_CLOSE_CHANNEL,
457 			    0x40, 0,
458 			    port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
459 
460 	if (i < 0)
461 		dev_err(&port->dev, "%s - close port failed %i\n",
462 			__func__, i);
463 
464 }
465 
466 static void qt2_disconnect(struct usb_serial *serial)
467 {
468 	struct qt2_serial_private *serial_priv = usb_get_serial_data(serial);
469 	struct qt2_port_private *port_priv;
470 	int i;
471 
472 	if (serial_priv->read_urb->status == -EINPROGRESS)
473 		usb_kill_urb(serial_priv->read_urb);
474 
475 	usb_free_urb(serial_priv->read_urb);
476 
477 	for (i = 0; i < serial->num_ports; i++) {
478 		port_priv = usb_get_serial_port_data(serial->port[i]);
479 
480 		if (port_priv->write_urb->status == -EINPROGRESS)
481 			usb_kill_urb(port_priv->write_urb);
482 		usb_free_urb(port_priv->write_urb);
483 	}
484 }
485 
486 static int get_serial_info(struct usb_serial_port *port,
487 			   struct serial_struct __user *retinfo)
488 {
489 	struct serial_struct tmp;
490 
491 	if (!retinfo)
492 		return -EFAULT;
493 
494 	memset(&tmp, 0, sizeof(tmp));
495 	tmp.line		= port->serial->minor;
496 	tmp.port		= 0;
497 	tmp.irq			= 0;
498 	tmp.flags		= ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
499 	tmp.xmit_fifo_size	= port->bulk_out_size;
500 	tmp.baud_base		= 9600;
501 	tmp.close_delay		= 5*HZ;
502 	tmp.closing_wait	= 30*HZ;
503 
504 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
505 		return -EFAULT;
506 	return 0;
507 }
508 
509 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
510 {
511 	struct qt2_port_private *priv = usb_get_serial_port_data(port);
512 	struct async_icount prev, cur;
513 	unsigned long flags;
514 
515 	spin_lock_irqsave(&priv->lock, flags);
516 	prev = priv->icount;
517 	spin_unlock_irqrestore(&priv->lock, flags);
518 
519 	while (1) {
520 		wait_event_interruptible(priv->delta_msr_wait,
521 					 ((priv->icount.rng != prev.rng) ||
522 					  (priv->icount.dsr != prev.dsr) ||
523 					  (priv->icount.dcd != prev.dcd) ||
524 					  (priv->icount.cts != prev.cts)));
525 
526 		if (signal_pending(current))
527 			return -ERESTARTSYS;
528 
529 		spin_lock_irqsave(&priv->lock, flags);
530 		cur = priv->icount;
531 		spin_unlock_irqrestore(&priv->lock, flags);
532 
533 		if ((prev.rng == cur.rng) &&
534 		    (prev.dsr == cur.dsr) &&
535 		    (prev.dcd == cur.dcd) &&
536 		    (prev.cts == cur.cts))
537 			return -EIO;
538 
539 		if ((arg & TIOCM_RNG && (prev.rng != cur.rng)) ||
540 		    (arg & TIOCM_DSR && (prev.dsr != cur.dsr)) ||
541 		    (arg & TIOCM_CD && (prev.dcd != cur.dcd)) ||
542 		    (arg & TIOCM_CTS && (prev.cts != cur.cts)))
543 			return 0;
544 	}
545 	return 0;
546 }
547 
548 static int qt2_get_icount(struct tty_struct *tty,
549 			  struct serial_icounter_struct *icount)
550 {
551 	struct usb_serial_port *port = tty->driver_data;
552 	struct qt2_port_private *priv = usb_get_serial_port_data(port);
553 	struct async_icount cnow = priv->icount;
554 
555 	icount->cts = cnow.cts;
556 	icount->dsr = cnow.dsr;
557 	icount->rng = cnow.rng;
558 	icount->dcd = cnow.dcd;
559 	icount->rx = cnow.rx;
560 	icount->tx = cnow.tx;
561 	icount->frame = cnow.frame;
562 	icount->overrun = cnow.overrun;
563 	icount->parity = cnow.parity;
564 	icount->brk = cnow.brk;
565 	icount->buf_overrun = cnow.buf_overrun;
566 
567 	return 0;
568 }
569 
570 static int qt2_ioctl(struct tty_struct *tty,
571 		     unsigned int cmd, unsigned long arg)
572 {
573 	struct usb_serial_port *port = tty->driver_data;
574 
575 	switch (cmd) {
576 	case TIOCGSERIAL:
577 		return get_serial_info(port,
578 				       (struct serial_struct __user *)arg);
579 
580 	case TIOCMIWAIT:
581 		return wait_modem_info(port, arg);
582 
583 	default:
584 		break;
585 	}
586 
587 	return -ENOIOCTLCMD;
588 }
589 
590 static void qt2_process_status(struct usb_serial_port *port, unsigned char *ch)
591 {
592 	switch (*ch) {
593 	case QT2_LINE_STATUS:
594 		qt2_update_lsr(port, ch + 1);
595 		break;
596 	case QT2_MODEM_STATUS:
597 		qt2_update_msr(port, ch + 1);
598 		break;
599 	}
600 }
601 
602 /* not needed, kept to document functionality */
603 static void qt2_process_xmit_empty(struct usb_serial_port *port,
604 				   unsigned char *ch)
605 {
606 	int bytes_written;
607 
608 	bytes_written = (int)(*ch) + (int)(*(ch + 1) << 4);
609 }
610 
611 /* not needed, kept to document functionality */
612 static void qt2_process_flush(struct usb_serial_port *port, unsigned char *ch)
613 {
614 	return;
615 }
616 
617 void qt2_process_read_urb(struct urb *urb)
618 {
619 	struct usb_serial *serial;
620 	struct qt2_serial_private *serial_priv;
621 	struct usb_serial_port *port;
622 	struct qt2_port_private *port_priv;
623 	struct tty_struct *tty;
624 	bool escapeflag;
625 	unsigned char *ch;
626 	int i;
627 	unsigned char newport;
628 	int len = urb->actual_length;
629 
630 	if (!len)
631 		return;
632 
633 	ch = urb->transfer_buffer;
634 	tty = NULL;
635 	serial = urb->context;
636 	serial_priv = usb_get_serial_data(serial);
637 	port = serial->port[serial_priv->current_port];
638 	port_priv = usb_get_serial_port_data(port);
639 
640 	if (port_priv->is_open)
641 		tty = tty_port_tty_get(&port->port);
642 
643 	for (i = 0; i < urb->actual_length; i++) {
644 		ch = (unsigned char *)urb->transfer_buffer + i;
645 		if ((i <= (len - 3)) &&
646 		    (*ch == QT2_CONTROL_BYTE) &&
647 		    (*(ch + 1) == QT2_CONTROL_BYTE)) {
648 			escapeflag = false;
649 			switch (*(ch + 2)) {
650 			case QT2_LINE_STATUS:
651 			case QT2_MODEM_STATUS:
652 				if (i > (len - 4)) {
653 					dev_warn(&port->dev,
654 						 "%s - status message too short\n",
655 						__func__);
656 					break;
657 				}
658 				qt2_process_status(port, ch + 2);
659 				i += 3;
660 				escapeflag = true;
661 				break;
662 			case QT2_XMIT_HOLD:
663 				if (i > (len - 5)) {
664 					dev_warn(&port->dev,
665 						 "%s - xmit_empty message too short\n",
666 						 __func__);
667 					break;
668 				}
669 				qt2_process_xmit_empty(port, ch + 3);
670 				i += 4;
671 				escapeflag = true;
672 				break;
673 			case QT2_CHANGE_PORT:
674 				if (i > (len - 4)) {
675 					dev_warn(&port->dev,
676 						 "%s - change_port message too short\n",
677 						 __func__);
678 					break;
679 				}
680 				if (tty) {
681 					tty_flip_buffer_push(tty);
682 					tty_kref_put(tty);
683 				}
684 
685 				newport = *(ch + 3);
686 
687 				if (newport > serial->num_ports) {
688 					dev_err(&port->dev,
689 						"%s - port change to invalid port: %i\n",
690 						__func__, newport);
691 					break;
692 				}
693 
694 				serial_priv->current_port = newport;
695 				port = serial->port[serial_priv->current_port];
696 				port_priv = usb_get_serial_port_data(port);
697 				if (port_priv->is_open)
698 					tty = tty_port_tty_get(&port->port);
699 				else
700 					tty = NULL;
701 				i += 3;
702 				escapeflag = true;
703 				break;
704 			case QT2_REC_FLUSH:
705 			case QT2_XMIT_FLUSH:
706 				qt2_process_flush(port, ch + 2);
707 				i += 2;
708 				escapeflag = true;
709 				break;
710 			case QT2_CONTROL_ESCAPE:
711 				tty_buffer_request_room(tty, 2);
712 				tty_insert_flip_string(tty, ch, 2);
713 				i += 2;
714 				escapeflag = true;
715 				break;
716 			default:
717 				dev_warn(&port->dev,
718 					 "%s - unsupported command %i\n",
719 					 __func__, *(ch + 2));
720 				break;
721 			}
722 			if (escapeflag)
723 				continue;
724 		}
725 
726 		if (tty) {
727 			tty_buffer_request_room(tty, 1);
728 			tty_insert_flip_string(tty, ch, 1);
729 		}
730 	}
731 
732 	if (tty) {
733 		tty_flip_buffer_push(tty);
734 		tty_kref_put(tty);
735 	}
736 }
737 
738 static void qt2_write_bulk_callback(struct urb *urb)
739 {
740 	struct usb_serial_port *port;
741 	struct qt2_port_private *port_priv;
742 
743 	port = urb->context;
744 	port_priv = usb_get_serial_port_data(port);
745 
746 	spin_lock(&port_priv->urb_lock);
747 
748 	port_priv->urb_in_use = false;
749 	usb_serial_port_softint(port);
750 
751 	spin_unlock(&port_priv->urb_lock);
752 
753 }
754 
755 static void qt2_read_bulk_callback(struct urb *urb)
756 {
757 	struct usb_serial *serial = urb->context;
758 	int status;
759 
760 	if (urb->status) {
761 		dev_warn(&serial->dev->dev,
762 			 "%s - non-zero urb status: %i\n", __func__,
763 			 urb->status);
764 		return;
765 	}
766 
767 	qt2_process_read_urb(urb);
768 
769 	status = usb_submit_urb(urb, GFP_ATOMIC);
770 	if (status != 0)
771 		dev_err(&serial->dev->dev,
772 			"%s - resubmit read urb failed: %i\n",
773 			__func__, status);
774 }
775 
776 static int qt2_setup_urbs(struct usb_serial *serial)
777 {
778 	struct usb_serial_port *port;
779 	struct usb_serial_port *port0;
780 	struct qt2_serial_private *serial_priv;
781 	struct qt2_port_private *port_priv;
782 	int pcount, status;
783 
784 	port0 = serial->port[0];
785 
786 	serial_priv = usb_get_serial_data(serial);
787 	serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
788 	if (!serial_priv->read_urb) {
789 		dev_err(&serial->dev->dev, "No free urbs available\n");
790 		return -ENOMEM;
791 	}
792 
793 	usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
794 			  usb_rcvbulkpipe(serial->dev,
795 					  port0->bulk_in_endpointAddress),
796 			  serial_priv->read_buffer,
797 			  sizeof(serial_priv->read_buffer),
798 			  qt2_read_bulk_callback, serial);
799 
800 	/* setup write_urb for each port */
801 	for (pcount = 0; pcount < serial->num_ports; pcount++) {
802 
803 		port = serial->port[pcount];
804 		port_priv = usb_get_serial_port_data(port);
805 
806 		port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
807 		if (!port_priv->write_urb) {
808 			dev_err(&serial->dev->dev,
809 				"failed to alloc write_urb for port %i\n",
810 				pcount);
811 			return -ENOMEM;
812 		}
813 
814 		usb_fill_bulk_urb(port_priv->write_urb,
815 				  serial->dev,
816 				  usb_sndbulkpipe(serial->dev,
817 						  port0->
818 						  bulk_out_endpointAddress),
819 				  port_priv->write_buffer,
820 				  sizeof(port_priv->write_buffer),
821 				  qt2_write_bulk_callback, port);
822 	}
823 
824 	status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
825 	if (status != 0) {
826 		dev_err(&serial->dev->dev,
827 			"%s - submit read urb failed %i\n", __func__, status);
828 		return status;
829 	}
830 
831 	return 0;
832 
833 }
834 
835 static int qt2_attach(struct usb_serial *serial)
836 {
837 	struct qt2_serial_private *serial_priv;
838 	struct qt2_port_private *port_priv;
839 	int status, pcount;
840 
841 	/* power on unit */
842 	status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
843 				 0xc2, 0x40, 0x8000, 0, NULL, 0,
844 				 QT2_USB_TIMEOUT);
845 	if (status < 0) {
846 		dev_err(&serial->dev->dev,
847 			"%s - failed to power on unit: %i\n", __func__, status);
848 		return status;
849 	}
850 
851 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
852 	if (!serial_priv) {
853 		dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
854 		return -ENOMEM;
855 	}
856 
857 	usb_set_serial_data(serial, serial_priv);
858 
859 	for (pcount = 0; pcount < serial->num_ports; pcount++) {
860 		port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
861 		if (!port_priv) {
862 			dev_err(&serial->dev->dev,
863 				"%s- kmalloc(%Zd) failed.\n", __func__,
864 				sizeof(*port_priv));
865 			pcount--;
866 			status = -ENOMEM;
867 			goto attach_failed;
868 		}
869 
870 		spin_lock_init(&port_priv->lock);
871 		spin_lock_init(&port_priv->urb_lock);
872 		init_waitqueue_head(&port_priv->delta_msr_wait);
873 
874 		port_priv->port = serial->port[pcount];
875 
876 		usb_set_serial_port_data(serial->port[pcount], port_priv);
877 	}
878 
879 	status = qt2_setup_urbs(serial);
880 	if (status != 0)
881 		goto attach_failed;
882 
883 	return 0;
884 
885 attach_failed:
886 	for (/* empty */; pcount >= 0; pcount--) {
887 		port_priv = usb_get_serial_port_data(serial->port[pcount]);
888 		kfree(port_priv);
889 	}
890 	kfree(serial_priv);
891 	return status;
892 }
893 
894 static int qt2_tiocmget(struct tty_struct *tty)
895 {
896 	struct usb_serial_port *port = tty->driver_data;
897 	struct usb_device *dev = port->serial->dev;
898 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
899 	u8 *d;
900 	int r;
901 
902 	d = kzalloc(2, GFP_KERNEL);
903 	if (!d)
904 		return -ENOMEM;
905 
906 	r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
907 	if (r < 0)
908 		goto mget_out;
909 
910 	r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
911 	if (r < 0)
912 		goto mget_out;
913 
914 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
915 	    (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
916 	    (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
917 	    (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
918 	    (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
919 	    (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
920 
921 mget_out:
922 	kfree(d);
923 	return r;
924 }
925 
926 static int qt2_tiocmset(struct tty_struct *tty,
927 			unsigned int set, unsigned int clear)
928 {
929 	struct qt2_port_private *port_priv;
930 
931 	port_priv = usb_get_serial_port_data(tty->driver_data);
932 	return update_mctrl(port_priv, set, clear);
933 }
934 
935 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
936 {
937 	struct usb_serial_port *port = tty->driver_data;
938 	struct qt2_port_private *port_priv;
939 	int status;
940 	u16 val;
941 
942 	port_priv = usb_get_serial_port_data(port);
943 
944 	if (!port_priv->is_open) {
945 		dev_err(&port->dev,
946 			"%s - port is not open\n", __func__);
947 		return;
948 	}
949 
950 	val = (break_state == -1) ? 1 : 0;
951 
952 	status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
953 				 val, port_priv->device_port);
954 	if (status < 0)
955 		dev_warn(&port->dev,
956 			 "%s - failed to send control message: %i\n", __func__,
957 			 status);
958 }
959 
960 
961 
962 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
963 {
964 	struct usb_device *dev = port->serial->dev;
965 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
966 
967 	mutex_lock(&port->serial->disc_mutex);
968 	if (!port->serial->disconnected) {
969 		/* Disable flow control */
970 		if (!on && qt2_setregister(dev, port_priv->device_port,
971 					   UART_MCR, 0) < 0)
972 			dev_warn(&port->dev, "error from flowcontrol urb\n");
973 		/* drop RTS and DTR */
974 		if (on)
975 			update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
976 		else
977 			update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
978 	}
979 	mutex_unlock(&port->serial->disc_mutex);
980 }
981 
982 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
983 {
984 	struct qt2_port_private *port_priv;
985 	u8 newMSR = (u8) *ch;
986 	unsigned long flags;
987 
988 	port_priv = usb_get_serial_port_data(port);
989 
990 	spin_lock_irqsave(&port_priv->lock, flags);
991 	port_priv->shadowMSR = newMSR;
992 	spin_unlock_irqrestore(&port_priv->lock, flags);
993 
994 	if (newMSR & UART_MSR_ANY_DELTA) {
995 		/* update input line counters */
996 		if (newMSR & UART_MSR_DCTS)
997 			port_priv->icount.cts++;
998 
999 		if (newMSR & UART_MSR_DDSR)
1000 			port_priv->icount.dsr++;
1001 
1002 		if (newMSR & UART_MSR_DDCD)
1003 			port_priv->icount.dcd++;
1004 
1005 		if (newMSR & UART_MSR_TERI)
1006 			port_priv->icount.rng++;
1007 
1008 		wake_up_interruptible(&port_priv->delta_msr_wait);
1009 	}
1010 }
1011 
1012 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
1013 {
1014 	struct qt2_port_private *port_priv;
1015 	struct async_icount *icount;
1016 	unsigned long flags;
1017 	u8 newLSR = (u8) *ch;
1018 
1019 	port_priv = usb_get_serial_port_data(port);
1020 
1021 	if (newLSR & UART_LSR_BI)
1022 		newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
1023 
1024 	spin_lock_irqsave(&port_priv->lock, flags);
1025 	port_priv->shadowLSR = newLSR;
1026 	spin_unlock_irqrestore(&port_priv->lock, flags);
1027 
1028 	icount = &port_priv->icount;
1029 
1030 	if (newLSR & UART_LSR_BRK_ERROR_BITS) {
1031 
1032 		if (newLSR & UART_LSR_BI)
1033 			icount->brk++;
1034 
1035 		if (newLSR & UART_LSR_OE)
1036 			icount->overrun++;
1037 
1038 		if (newLSR & UART_LSR_PE)
1039 			icount->parity++;
1040 
1041 		if (newLSR & UART_LSR_FE)
1042 			icount->frame++;
1043 	}
1044 
1045 }
1046 
1047 static int qt2_write_room(struct tty_struct *tty)
1048 {
1049 	struct usb_serial_port *port = tty->driver_data;
1050 	struct qt2_port_private *port_priv;
1051 	unsigned long flags = 0;
1052 	int r;
1053 
1054 	port_priv = usb_get_serial_port_data(port);
1055 
1056 	spin_lock_irqsave(&port_priv->urb_lock, flags);
1057 
1058 	if (port_priv->urb_in_use)
1059 		r = 0;
1060 	else
1061 		r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
1062 
1063 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1064 
1065 	return r;
1066 }
1067 
1068 static int qt2_write(struct tty_struct *tty,
1069 		     struct usb_serial_port *port,
1070 		     const unsigned char *buf, int count)
1071 {
1072 	struct qt2_port_private *port_priv;
1073 	struct urb *write_urb;
1074 	unsigned char *data;
1075 	unsigned long flags;
1076 	int status;
1077 	int bytes_out = 0;
1078 
1079 	port_priv = usb_get_serial_port_data(port);
1080 
1081 	if (port_priv->write_urb == NULL) {
1082 		dev_err(&port->dev, "%s - no output urb\n", __func__);
1083 		return 0;
1084 	}
1085 	write_urb = port_priv->write_urb;
1086 
1087 	count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
1088 
1089 	data = write_urb->transfer_buffer;
1090 	spin_lock_irqsave(&port_priv->urb_lock, flags);
1091 	if (port_priv->urb_in_use == true) {
1092 		printk(KERN_INFO "qt2_write - urb is in use\n");
1093 		goto write_out;
1094 	}
1095 
1096 	*data++ = QT2_CONTROL_BYTE;
1097 	*data++ = QT2_CONTROL_BYTE;
1098 	*data++ = port_priv->device_port;
1099 	put_unaligned_le16(count, data);
1100 	data += 2;
1101 	memcpy(data, buf, count);
1102 
1103 	write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
1104 
1105 	status = usb_submit_urb(write_urb, GFP_ATOMIC);
1106 	if (status == 0) {
1107 		port_priv->urb_in_use = true;
1108 		bytes_out += count;
1109 	}
1110 
1111 write_out:
1112 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1113 	return bytes_out;
1114 }
1115 
1116 
1117 static struct usb_serial_driver qt2_device = {
1118 	.driver = {
1119 		.owner = THIS_MODULE,
1120 		.name = "quatech-serial",
1121 	},
1122 	.description	     = DRIVER_DESC,
1123 	.id_table	     = id_table,
1124 	.open		     = qt2_open,
1125 	.close		     = qt2_close,
1126 	.write               = qt2_write,
1127 	.write_room          = qt2_write_room,
1128 	.calc_num_ports      = qt2_calc_num_ports,
1129 	.attach              = qt2_attach,
1130 	.release             = qt2_release,
1131 	.disconnect          = qt2_disconnect,
1132 	.dtr_rts             = qt2_dtr_rts,
1133 	.break_ctl           = qt2_break_ctl,
1134 	.tiocmget            = qt2_tiocmget,
1135 	.tiocmset            = qt2_tiocmset,
1136 	.get_icount	     = qt2_get_icount,
1137 	.ioctl               = qt2_ioctl,
1138 	.set_termios         = qt2_set_termios,
1139 };
1140 
1141 static struct usb_serial_driver *const serial_drivers[] = {
1142 	&qt2_device, NULL
1143 };
1144 
1145 module_usb_serial_driver(serial_drivers, id_table);
1146 
1147 MODULE_DESCRIPTION(DRIVER_DESC);
1148 MODULE_LICENSE("GPL");
1149 
1150 module_param(debug, bool, S_IRUGO | S_IWUSR);
1151 MODULE_PARM_DESC(debug, "Debug enabled or not");
1152