xref: /openbmc/linux/drivers/usb/serial/quatech2.c (revision d7a3d85e)
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/slab.h>
19 #include <linux/tty.h>
20 #include <linux/tty_driver.h>
21 #include <linux/tty_flip.h>
22 #include <linux/module.h>
23 #include <linux/serial.h>
24 #include <linux/usb.h>
25 #include <linux/usb/serial.h>
26 #include <linux/serial_reg.h>
27 #include <linux/uaccess.h>
28 
29 /* default urb timeout for usb operations */
30 #define QT2_USB_TIMEOUT USB_CTRL_SET_TIMEOUT
31 
32 #define QT_OPEN_CLOSE_CHANNEL       0xca
33 #define QT_SET_GET_DEVICE           0xc2
34 #define QT_SET_GET_REGISTER         0xc0
35 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
36 #define QT_SET_ATF                  0xcd
37 #define QT_TRANSFER_IN              0xc0
38 #define QT_HW_FLOW_CONTROL_MASK     0xc5
39 #define QT_SW_FLOW_CONTROL_MASK     0xc6
40 #define QT2_BREAK_CONTROL	    0xc8
41 #define QT2_GET_SET_UART            0xc1
42 #define QT2_FLUSH_DEVICE	    0xc4
43 #define QT2_GET_SET_QMCR            0xe1
44 #define QT2_QMCR_RS232              0x40
45 #define QT2_QMCR_RS422              0x10
46 
47 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
48 
49 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
50 
51 /* status bytes for the device */
52 #define QT2_CONTROL_BYTE    0x1b
53 #define QT2_LINE_STATUS     0x00  /* following 1 byte is line status */
54 #define QT2_MODEM_STATUS    0x01  /* following 1 byte is modem status */
55 #define QT2_XMIT_HOLD       0x02  /* following 2 bytes are ?? */
56 #define QT2_CHANGE_PORT     0x03  /* following 1 byte is port to change to */
57 #define QT2_REC_FLUSH       0x04  /* no following info */
58 #define QT2_XMIT_FLUSH      0x05  /* no following info */
59 #define QT2_CONTROL_ESCAPE  0xff  /* pass through previous 2 control bytes */
60 
61 #define  MAX_BAUD_RATE              921600
62 #define  DEFAULT_BAUD_RATE          9600
63 
64 #define QT2_READ_BUFFER_SIZE    512  /* size of read buffer */
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;
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;
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->read_buffer);
146 	kfree(serial_priv);
147 }
148 
149 static inline int calc_baud_divisor(int baudrate)
150 {
151 	int divisor, rem;
152 
153 	divisor = MAX_BAUD_RATE / baudrate;
154 	rem = MAX_BAUD_RATE % baudrate;
155 	/* Round to nearest divisor */
156 	if (((rem * 2) >= baudrate) && (baudrate != 110))
157 		divisor++;
158 
159 	return divisor;
160 }
161 
162 static inline int qt2_set_port_config(struct usb_device *dev,
163 				      unsigned char port_number,
164 				      u16 baudrate, u16 lcr)
165 {
166 	int divisor = calc_baud_divisor(baudrate);
167 	u16 index = ((u16) (lcr << 8) | (u16) (port_number));
168 
169 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
170 			       QT2_GET_SET_UART, 0x40,
171 			       divisor, index, NULL, 0, QT2_USB_TIMEOUT);
172 }
173 
174 static inline int qt2_control_msg(struct usb_device *dev,
175 				  u8 request, u16 data, u16 index)
176 {
177 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
178 			       request, 0x40, data, index,
179 			       NULL, 0, QT2_USB_TIMEOUT);
180 }
181 
182 static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
183 {
184 	u16 x = ((u16) (data[1] << 8) | (u16) (data[0]));
185 
186 	return qt2_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
187 }
188 
189 
190 static inline int qt2_getdevice(struct usb_device *dev, u8 *data)
191 {
192 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
193 			       QT_SET_GET_DEVICE, 0xc0, 0, 0,
194 			       data, 3, QT2_USB_TIMEOUT);
195 }
196 
197 static inline int qt2_getregister(struct usb_device *dev,
198 				  u8 uart,
199 				  u8 reg,
200 				  u8 *data)
201 {
202 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
203 			       QT_SET_GET_REGISTER, 0xc0, reg,
204 			       uart, data, sizeof(*data), QT2_USB_TIMEOUT);
205 
206 }
207 
208 static inline int qt2_setregister(struct usb_device *dev,
209 				  u8 uart, u8 reg, u16 data)
210 {
211 	u16 value = (data << 8) | reg;
212 
213 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
214 			       QT_SET_GET_REGISTER, 0x40, value, uart,
215 			       NULL, 0, QT2_USB_TIMEOUT);
216 }
217 
218 static inline int update_mctrl(struct qt2_port_private *port_priv,
219 			       unsigned int set, unsigned int clear)
220 {
221 	struct usb_serial_port *port = port_priv->port;
222 	struct usb_device *dev = port->serial->dev;
223 	unsigned urb_value;
224 	int status;
225 
226 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
227 		dev_dbg(&port->dev,
228 			"update_mctrl - DTR|RTS not being set|cleared\n");
229 		return 0;	/* no change */
230 	}
231 
232 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
233 	urb_value = 0;
234 	if (set & TIOCM_DTR)
235 		urb_value |= UART_MCR_DTR;
236 	if (set & TIOCM_RTS)
237 		urb_value |= UART_MCR_RTS;
238 
239 	status = qt2_setregister(dev, port_priv->device_port, UART_MCR,
240 				 urb_value);
241 	if (status < 0)
242 		dev_err(&port->dev,
243 			"update_mctrl - Error from MODEM_CTRL urb: %i\n",
244 			status);
245 	return status;
246 }
247 
248 static int qt2_calc_num_ports(struct usb_serial *serial)
249 {
250 	struct qt2_device_detail d;
251 	int i;
252 
253 	for (i = 0; d = qt2_device_details[i], d.product_id != 0; i++) {
254 		if (d.product_id == le16_to_cpu(serial->dev->descriptor.idProduct))
255 			return d.num_ports;
256 	}
257 
258 	/* we didn't recognize the device */
259 	dev_err(&serial->dev->dev,
260 		 "don't know the number of ports, assuming 1\n");
261 
262 	return 1;
263 }
264 
265 static void qt2_set_termios(struct tty_struct *tty,
266 			    struct usb_serial_port *port,
267 			    struct ktermios *old_termios)
268 {
269 	struct usb_device *dev = port->serial->dev;
270 	struct qt2_port_private *port_priv;
271 	struct ktermios *termios = &tty->termios;
272 	u16 baud;
273 	unsigned int cflag = termios->c_cflag;
274 	u16 new_lcr = 0;
275 	int status;
276 
277 	port_priv = usb_get_serial_port_data(port);
278 
279 	if (cflag & PARENB) {
280 		if (cflag & PARODD)
281 			new_lcr |= UART_LCR_PARITY;
282 		else
283 			new_lcr |= SERIAL_EVEN_PARITY;
284 	}
285 
286 	switch (cflag & CSIZE) {
287 	case CS5:
288 		new_lcr |= UART_LCR_WLEN5;
289 		break;
290 	case CS6:
291 		new_lcr |= UART_LCR_WLEN6;
292 		break;
293 	case CS7:
294 		new_lcr |= UART_LCR_WLEN7;
295 		break;
296 	default:
297 	case CS8:
298 		new_lcr |= UART_LCR_WLEN8;
299 		break;
300 	}
301 
302 	baud = tty_get_baud_rate(tty);
303 	if (!baud)
304 		baud = 9600;
305 
306 	status = qt2_set_port_config(dev, port_priv->device_port, baud,
307 				     new_lcr);
308 	if (status < 0)
309 		dev_err(&port->dev, "%s - qt2_set_port_config failed: %i\n",
310 			__func__, status);
311 
312 	if (cflag & CRTSCTS)
313 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
314 					 SERIAL_CRTSCTS,
315 					 port_priv->device_port);
316 	else
317 		status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
318 					 0, port_priv->device_port);
319 	if (status < 0)
320 		dev_err(&port->dev, "%s - set HW flow control failed: %i\n",
321 			__func__, status);
322 
323 	if (I_IXOFF(tty) || I_IXON(tty)) {
324 		u16 x = ((u16) (START_CHAR(tty) << 8) | (u16) (STOP_CHAR(tty)));
325 
326 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
327 					 x, port_priv->device_port);
328 	} else
329 		status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
330 					 0, port_priv->device_port);
331 
332 	if (status < 0)
333 		dev_err(&port->dev, "%s - set SW flow control failed: %i\n",
334 			__func__, status);
335 
336 }
337 
338 static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port)
339 {
340 	struct usb_serial *serial;
341 	struct qt2_port_private *port_priv;
342 	u8 *data;
343 	u16 device_port;
344 	int status;
345 	unsigned long flags;
346 
347 	device_port = port->port_number;
348 
349 	serial = port->serial;
350 
351 	port_priv = usb_get_serial_port_data(port);
352 
353 	/* set the port to RS232 mode */
354 	status = qt2_control_msg(serial->dev, QT2_GET_SET_QMCR,
355 				 QT2_QMCR_RS232, device_port);
356 	if (status < 0) {
357 		dev_err(&port->dev,
358 			"%s failed to set RS232 mode for port %i error %i\n",
359 			__func__, device_port, status);
360 		return status;
361 	}
362 
363 	data = kzalloc(2, GFP_KERNEL);
364 	if (!data)
365 		return -ENOMEM;
366 
367 	/* open the port */
368 	status = usb_control_msg(serial->dev,
369 				 usb_rcvctrlpipe(serial->dev, 0),
370 				 QT_OPEN_CLOSE_CHANNEL,
371 				 0xc0, 0,
372 				 device_port, data, 2, QT2_USB_TIMEOUT);
373 
374 	if (status < 0) {
375 		dev_err(&port->dev, "%s - open port failed %i\n", __func__,
376 			status);
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 	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->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 static 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 		return -ENOMEM;
680 
681 	usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
682 			  usb_rcvbulkpipe(serial->dev,
683 					  port0->bulk_in_endpointAddress),
684 			  serial_priv->read_buffer,
685 			  QT2_READ_BUFFER_SIZE,
686 			  qt2_read_bulk_callback, serial);
687 
688 	status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
689 	if (status != 0) {
690 		dev_err(&serial->dev->dev,
691 			"%s - submit read urb failed %i\n", __func__, status);
692 		usb_free_urb(serial_priv->read_urb);
693 		return status;
694 	}
695 
696 	return 0;
697 }
698 
699 static int qt2_attach(struct usb_serial *serial)
700 {
701 	struct qt2_serial_private *serial_priv;
702 	int status;
703 
704 	/* power on unit */
705 	status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
706 				 0xc2, 0x40, 0x8000, 0, NULL, 0,
707 				 QT2_USB_TIMEOUT);
708 	if (status < 0) {
709 		dev_err(&serial->dev->dev,
710 			"%s - failed to power on unit: %i\n", __func__, status);
711 		return status;
712 	}
713 
714 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
715 	if (!serial_priv)
716 		return -ENOMEM;
717 
718 	serial_priv->read_buffer = kmalloc(QT2_READ_BUFFER_SIZE, GFP_KERNEL);
719 	if (!serial_priv->read_buffer) {
720 		status = -ENOMEM;
721 		goto err_buf;
722 	}
723 
724 	usb_set_serial_data(serial, serial_priv);
725 
726 	status = qt2_setup_urbs(serial);
727 	if (status != 0)
728 		goto attach_failed;
729 
730 	return 0;
731 
732 attach_failed:
733 	kfree(serial_priv->read_buffer);
734 err_buf:
735 	kfree(serial_priv);
736 	return status;
737 }
738 
739 static int qt2_port_probe(struct usb_serial_port *port)
740 {
741 	struct usb_serial *serial = port->serial;
742 	struct qt2_port_private *port_priv;
743 	u8 bEndpointAddress;
744 
745 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
746 	if (!port_priv)
747 		return -ENOMEM;
748 
749 	spin_lock_init(&port_priv->lock);
750 	spin_lock_init(&port_priv->urb_lock);
751 	port_priv->port = port;
752 
753 	port_priv->write_buffer = kmalloc(QT2_WRITE_BUFFER_SIZE, GFP_KERNEL);
754 	if (!port_priv->write_buffer)
755 		goto err_buf;
756 
757 	port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
758 	if (!port_priv->write_urb)
759 		goto err_urb;
760 
761 	bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
762 	usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
763 				usb_sndbulkpipe(serial->dev, bEndpointAddress),
764 				port_priv->write_buffer,
765 				QT2_WRITE_BUFFER_SIZE,
766 				qt2_write_bulk_callback, port);
767 
768 	usb_set_serial_port_data(port, port_priv);
769 
770 	return 0;
771 err_urb:
772 	kfree(port_priv->write_buffer);
773 err_buf:
774 	kfree(port_priv);
775 	return -ENOMEM;
776 }
777 
778 static int qt2_port_remove(struct usb_serial_port *port)
779 {
780 	struct qt2_port_private *port_priv;
781 
782 	port_priv = usb_get_serial_port_data(port);
783 	usb_free_urb(port_priv->write_urb);
784 	kfree(port_priv->write_buffer);
785 	kfree(port_priv);
786 
787 	return 0;
788 }
789 
790 static int qt2_tiocmget(struct tty_struct *tty)
791 {
792 	struct usb_serial_port *port = tty->driver_data;
793 	struct usb_device *dev = port->serial->dev;
794 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
795 	u8 *d;
796 	int r;
797 
798 	d = kzalloc(2, GFP_KERNEL);
799 	if (!d)
800 		return -ENOMEM;
801 
802 	r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
803 	if (r < 0)
804 		goto mget_out;
805 
806 	r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
807 	if (r < 0)
808 		goto mget_out;
809 
810 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
811 	    (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
812 	    (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
813 	    (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
814 	    (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
815 	    (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
816 
817 mget_out:
818 	kfree(d);
819 	return r;
820 }
821 
822 static int qt2_tiocmset(struct tty_struct *tty,
823 			unsigned int set, unsigned int clear)
824 {
825 	struct qt2_port_private *port_priv;
826 
827 	port_priv = usb_get_serial_port_data(tty->driver_data);
828 	return update_mctrl(port_priv, set, clear);
829 }
830 
831 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
832 {
833 	struct usb_serial_port *port = tty->driver_data;
834 	struct qt2_port_private *port_priv;
835 	int status;
836 	u16 val;
837 
838 	port_priv = usb_get_serial_port_data(port);
839 
840 	val = (break_state == -1) ? 1 : 0;
841 
842 	status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
843 				 val, port_priv->device_port);
844 	if (status < 0)
845 		dev_warn(&port->dev,
846 			 "%s - failed to send control message: %i\n", __func__,
847 			 status);
848 }
849 
850 
851 
852 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
853 {
854 	struct usb_device *dev = port->serial->dev;
855 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
856 
857 	/* Disable flow control */
858 	if (!on) {
859 		if (qt2_setregister(dev, port_priv->device_port,
860 					   UART_MCR, 0) < 0)
861 			dev_warn(&port->dev, "error from flowcontrol urb\n");
862 	}
863 	/* drop RTS and DTR */
864 	if (on)
865 		update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
866 	else
867 		update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
868 }
869 
870 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
871 {
872 	struct qt2_port_private *port_priv;
873 	u8 newMSR = (u8) *ch;
874 	unsigned long flags;
875 
876 	port_priv = usb_get_serial_port_data(port);
877 
878 	spin_lock_irqsave(&port_priv->lock, flags);
879 	port_priv->shadowMSR = newMSR;
880 	spin_unlock_irqrestore(&port_priv->lock, flags);
881 
882 	if (newMSR & UART_MSR_ANY_DELTA) {
883 		/* update input line counters */
884 		if (newMSR & UART_MSR_DCTS)
885 			port->icount.cts++;
886 		if (newMSR & UART_MSR_DDSR)
887 			port->icount.dsr++;
888 		if (newMSR & UART_MSR_DDCD)
889 			port->icount.dcd++;
890 		if (newMSR & UART_MSR_TERI)
891 			port->icount.rng++;
892 
893 		wake_up_interruptible(&port->port.delta_msr_wait);
894 	}
895 }
896 
897 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
898 {
899 	struct qt2_port_private *port_priv;
900 	struct async_icount *icount;
901 	unsigned long flags;
902 	u8 newLSR = (u8) *ch;
903 
904 	port_priv = usb_get_serial_port_data(port);
905 
906 	if (newLSR & UART_LSR_BI)
907 		newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
908 
909 	spin_lock_irqsave(&port_priv->lock, flags);
910 	port_priv->shadowLSR = newLSR;
911 	spin_unlock_irqrestore(&port_priv->lock, flags);
912 
913 	icount = &port->icount;
914 
915 	if (newLSR & UART_LSR_BRK_ERROR_BITS) {
916 
917 		if (newLSR & UART_LSR_BI)
918 			icount->brk++;
919 
920 		if (newLSR & UART_LSR_OE)
921 			icount->overrun++;
922 
923 		if (newLSR & UART_LSR_PE)
924 			icount->parity++;
925 
926 		if (newLSR & UART_LSR_FE)
927 			icount->frame++;
928 	}
929 
930 }
931 
932 static int qt2_write_room(struct tty_struct *tty)
933 {
934 	struct usb_serial_port *port = tty->driver_data;
935 	struct qt2_port_private *port_priv;
936 	unsigned long flags = 0;
937 	int r;
938 
939 	port_priv = usb_get_serial_port_data(port);
940 
941 	spin_lock_irqsave(&port_priv->urb_lock, flags);
942 
943 	if (port_priv->urb_in_use)
944 		r = 0;
945 	else
946 		r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
947 
948 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
949 
950 	return r;
951 }
952 
953 static int qt2_write(struct tty_struct *tty,
954 		     struct usb_serial_port *port,
955 		     const unsigned char *buf, int count)
956 {
957 	struct qt2_port_private *port_priv;
958 	struct urb *write_urb;
959 	unsigned char *data;
960 	unsigned long flags;
961 	int status;
962 	int bytes_out = 0;
963 
964 	port_priv = usb_get_serial_port_data(port);
965 
966 	if (port_priv->write_urb == NULL) {
967 		dev_err(&port->dev, "%s - no output urb\n", __func__);
968 		return 0;
969 	}
970 	write_urb = port_priv->write_urb;
971 
972 	count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
973 
974 	data = write_urb->transfer_buffer;
975 	spin_lock_irqsave(&port_priv->urb_lock, flags);
976 	if (port_priv->urb_in_use == true) {
977 		dev_err(&port->dev, "qt2_write - urb is in use\n");
978 		goto write_out;
979 	}
980 
981 	*data++ = QT2_CONTROL_BYTE;
982 	*data++ = QT2_CONTROL_BYTE;
983 	*data++ = port_priv->device_port;
984 	put_unaligned_le16(count, data);
985 	data += 2;
986 	memcpy(data, buf, count);
987 
988 	write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
989 
990 	status = usb_submit_urb(write_urb, GFP_ATOMIC);
991 	if (status == 0) {
992 		port_priv->urb_in_use = true;
993 		bytes_out += count;
994 	}
995 
996 write_out:
997 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
998 	return bytes_out;
999 }
1000 
1001 
1002 static struct usb_serial_driver qt2_device = {
1003 	.driver = {
1004 		.owner = THIS_MODULE,
1005 		.name = "quatech-serial",
1006 	},
1007 	.description	     = DRIVER_DESC,
1008 	.id_table	     = id_table,
1009 	.open		     = qt2_open,
1010 	.close		     = qt2_close,
1011 	.write               = qt2_write,
1012 	.write_room          = qt2_write_room,
1013 	.calc_num_ports      = qt2_calc_num_ports,
1014 	.attach              = qt2_attach,
1015 	.release             = qt2_release,
1016 	.disconnect          = qt2_disconnect,
1017 	.port_probe          = qt2_port_probe,
1018 	.port_remove         = qt2_port_remove,
1019 	.dtr_rts             = qt2_dtr_rts,
1020 	.break_ctl           = qt2_break_ctl,
1021 	.tiocmget            = qt2_tiocmget,
1022 	.tiocmset            = qt2_tiocmset,
1023 	.tiocmiwait          = usb_serial_generic_tiocmiwait,
1024 	.get_icount	     = usb_serial_generic_get_icount,
1025 	.ioctl               = qt2_ioctl,
1026 	.set_termios         = qt2_set_termios,
1027 };
1028 
1029 static struct usb_serial_driver *const serial_drivers[] = {
1030 	&qt2_device, NULL
1031 };
1032 
1033 module_usb_serial_driver(serial_drivers, id_table);
1034 
1035 MODULE_DESCRIPTION(DRIVER_DESC);
1036 MODULE_LICENSE("GPL");
1037