xref: /openbmc/linux/drivers/usb/serial/quatech2.c (revision 842ed298)
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 tty_struct *tty,
457 			   struct serial_struct *ss)
458 {
459 	struct usb_serial_port *port = tty->driver_data;
460 
461 	ss->line		= port->minor;
462 	ss->port		= 0;
463 	ss->irq			= 0;
464 	ss->xmit_fifo_size	= port->bulk_out_size;
465 	ss->baud_base		= 9600;
466 	ss->close_delay		= 5*HZ;
467 	ss->closing_wait	= 30*HZ;
468 	return 0;
469 }
470 
471 static void qt2_process_status(struct usb_serial_port *port, unsigned char *ch)
472 {
473 	switch (*ch) {
474 	case QT2_LINE_STATUS:
475 		qt2_update_lsr(port, ch + 1);
476 		break;
477 	case QT2_MODEM_STATUS:
478 		qt2_update_msr(port, ch + 1);
479 		break;
480 	}
481 }
482 
483 static void qt2_process_read_urb(struct urb *urb)
484 {
485 	struct usb_serial *serial;
486 	struct qt2_serial_private *serial_priv;
487 	struct usb_serial_port *port;
488 	bool escapeflag;
489 	unsigned char *ch;
490 	int i;
491 	unsigned char newport;
492 	int len = urb->actual_length;
493 
494 	if (!len)
495 		return;
496 
497 	ch = urb->transfer_buffer;
498 	serial = urb->context;
499 	serial_priv = usb_get_serial_data(serial);
500 	port = serial->port[serial_priv->current_port];
501 
502 	for (i = 0; i < urb->actual_length; i++) {
503 		ch = (unsigned char *)urb->transfer_buffer + i;
504 		if ((i <= (len - 3)) &&
505 		    (*ch == QT2_CONTROL_BYTE) &&
506 		    (*(ch + 1) == QT2_CONTROL_BYTE)) {
507 			escapeflag = false;
508 			switch (*(ch + 2)) {
509 			case QT2_LINE_STATUS:
510 			case QT2_MODEM_STATUS:
511 				if (i > (len - 4)) {
512 					dev_warn(&port->dev,
513 						 "%s - status message too short\n",
514 						__func__);
515 					break;
516 				}
517 				qt2_process_status(port, ch + 2);
518 				i += 3;
519 				escapeflag = true;
520 				break;
521 			case QT2_XMIT_HOLD:
522 				if (i > (len - 5)) {
523 					dev_warn(&port->dev,
524 						 "%s - xmit_empty message too short\n",
525 						 __func__);
526 					break;
527 				}
528 				/* bytes_written = (ch[1] << 4) + ch[0]; */
529 				i += 4;
530 				escapeflag = true;
531 				break;
532 			case QT2_CHANGE_PORT:
533 				if (i > (len - 4)) {
534 					dev_warn(&port->dev,
535 						 "%s - change_port message too short\n",
536 						 __func__);
537 					break;
538 				}
539 				tty_flip_buffer_push(&port->port);
540 
541 				newport = *(ch + 3);
542 
543 				if (newport > serial->num_ports) {
544 					dev_err(&port->dev,
545 						"%s - port change to invalid port: %i\n",
546 						__func__, newport);
547 					break;
548 				}
549 
550 				serial_priv->current_port = newport;
551 				port = serial->port[serial_priv->current_port];
552 				i += 3;
553 				escapeflag = true;
554 				break;
555 			case QT2_REC_FLUSH:
556 			case QT2_XMIT_FLUSH:
557 				i += 2;
558 				escapeflag = true;
559 				break;
560 			case QT2_CONTROL_ESCAPE:
561 				tty_insert_flip_string(&port->port, ch, 2);
562 				i += 2;
563 				escapeflag = true;
564 				break;
565 			default:
566 				dev_warn(&port->dev,
567 					 "%s - unsupported command %i\n",
568 					 __func__, *(ch + 2));
569 				break;
570 			}
571 			if (escapeflag)
572 				continue;
573 		}
574 
575 		tty_insert_flip_char(&port->port, *ch, TTY_NORMAL);
576 	}
577 
578 	tty_flip_buffer_push(&port->port);
579 }
580 
581 static void qt2_write_bulk_callback(struct urb *urb)
582 {
583 	struct usb_serial_port *port;
584 	struct qt2_port_private *port_priv;
585 	unsigned long flags;
586 
587 	port = urb->context;
588 	port_priv = usb_get_serial_port_data(port);
589 
590 	spin_lock_irqsave(&port_priv->urb_lock, flags);
591 
592 	port_priv->urb_in_use = false;
593 	usb_serial_port_softint(port);
594 
595 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
596 
597 }
598 
599 static void qt2_read_bulk_callback(struct urb *urb)
600 {
601 	struct usb_serial *serial = urb->context;
602 	int status;
603 
604 	if (urb->status) {
605 		dev_warn(&serial->dev->dev,
606 			 "%s - non-zero urb status: %i\n", __func__,
607 			 urb->status);
608 		return;
609 	}
610 
611 	qt2_process_read_urb(urb);
612 
613 	status = usb_submit_urb(urb, GFP_ATOMIC);
614 	if (status != 0)
615 		dev_err(&serial->dev->dev,
616 			"%s - resubmit read urb failed: %i\n",
617 			__func__, status);
618 }
619 
620 static int qt2_setup_urbs(struct usb_serial *serial)
621 {
622 	struct usb_serial_port *port0;
623 	struct qt2_serial_private *serial_priv;
624 	int status;
625 
626 	port0 = serial->port[0];
627 
628 	serial_priv = usb_get_serial_data(serial);
629 	serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
630 	if (!serial_priv->read_urb)
631 		return -ENOMEM;
632 
633 	usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
634 			  usb_rcvbulkpipe(serial->dev,
635 					  port0->bulk_in_endpointAddress),
636 			  serial_priv->read_buffer,
637 			  QT2_READ_BUFFER_SIZE,
638 			  qt2_read_bulk_callback, serial);
639 
640 	status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
641 	if (status != 0) {
642 		dev_err(&serial->dev->dev,
643 			"%s - submit read urb failed %i\n", __func__, status);
644 		usb_free_urb(serial_priv->read_urb);
645 		return status;
646 	}
647 
648 	return 0;
649 }
650 
651 static int qt2_attach(struct usb_serial *serial)
652 {
653 	struct qt2_serial_private *serial_priv;
654 	int status;
655 
656 	/* power on unit */
657 	status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
658 				 0xc2, 0x40, 0x8000, 0, NULL, 0,
659 				 QT2_USB_TIMEOUT);
660 	if (status < 0) {
661 		dev_err(&serial->dev->dev,
662 			"%s - failed to power on unit: %i\n", __func__, status);
663 		return status;
664 	}
665 
666 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
667 	if (!serial_priv)
668 		return -ENOMEM;
669 
670 	serial_priv->read_buffer = kmalloc(QT2_READ_BUFFER_SIZE, GFP_KERNEL);
671 	if (!serial_priv->read_buffer) {
672 		status = -ENOMEM;
673 		goto err_buf;
674 	}
675 
676 	usb_set_serial_data(serial, serial_priv);
677 
678 	status = qt2_setup_urbs(serial);
679 	if (status != 0)
680 		goto attach_failed;
681 
682 	return 0;
683 
684 attach_failed:
685 	kfree(serial_priv->read_buffer);
686 err_buf:
687 	kfree(serial_priv);
688 	return status;
689 }
690 
691 static int qt2_port_probe(struct usb_serial_port *port)
692 {
693 	struct usb_serial *serial = port->serial;
694 	struct qt2_port_private *port_priv;
695 	u8 bEndpointAddress;
696 
697 	port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
698 	if (!port_priv)
699 		return -ENOMEM;
700 
701 	spin_lock_init(&port_priv->lock);
702 	spin_lock_init(&port_priv->urb_lock);
703 	port_priv->port = port;
704 
705 	port_priv->write_buffer = kmalloc(QT2_WRITE_BUFFER_SIZE, GFP_KERNEL);
706 	if (!port_priv->write_buffer)
707 		goto err_buf;
708 
709 	port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
710 	if (!port_priv->write_urb)
711 		goto err_urb;
712 
713 	bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
714 	usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
715 				usb_sndbulkpipe(serial->dev, bEndpointAddress),
716 				port_priv->write_buffer,
717 				QT2_WRITE_BUFFER_SIZE,
718 				qt2_write_bulk_callback, port);
719 
720 	usb_set_serial_port_data(port, port_priv);
721 
722 	return 0;
723 err_urb:
724 	kfree(port_priv->write_buffer);
725 err_buf:
726 	kfree(port_priv);
727 	return -ENOMEM;
728 }
729 
730 static int qt2_port_remove(struct usb_serial_port *port)
731 {
732 	struct qt2_port_private *port_priv;
733 
734 	port_priv = usb_get_serial_port_data(port);
735 	usb_free_urb(port_priv->write_urb);
736 	kfree(port_priv->write_buffer);
737 	kfree(port_priv);
738 
739 	return 0;
740 }
741 
742 static int qt2_tiocmget(struct tty_struct *tty)
743 {
744 	struct usb_serial_port *port = tty->driver_data;
745 	struct usb_device *dev = port->serial->dev;
746 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
747 	u8 *d;
748 	int r;
749 
750 	d = kzalloc(2, GFP_KERNEL);
751 	if (!d)
752 		return -ENOMEM;
753 
754 	r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
755 	if (r < 0)
756 		goto mget_out;
757 
758 	r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
759 	if (r < 0)
760 		goto mget_out;
761 
762 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
763 	    (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
764 	    (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
765 	    (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
766 	    (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
767 	    (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
768 
769 mget_out:
770 	kfree(d);
771 	return r;
772 }
773 
774 static int qt2_tiocmset(struct tty_struct *tty,
775 			unsigned int set, unsigned int clear)
776 {
777 	struct qt2_port_private *port_priv;
778 
779 	port_priv = usb_get_serial_port_data(tty->driver_data);
780 	return update_mctrl(port_priv, set, clear);
781 }
782 
783 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
784 {
785 	struct usb_serial_port *port = tty->driver_data;
786 	struct qt2_port_private *port_priv;
787 	int status;
788 	u16 val;
789 
790 	port_priv = usb_get_serial_port_data(port);
791 
792 	val = (break_state == -1) ? 1 : 0;
793 
794 	status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
795 				 val, port_priv->device_port);
796 	if (status < 0)
797 		dev_warn(&port->dev,
798 			 "%s - failed to send control message: %i\n", __func__,
799 			 status);
800 }
801 
802 
803 
804 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
805 {
806 	struct usb_device *dev = port->serial->dev;
807 	struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
808 
809 	/* Disable flow control */
810 	if (!on) {
811 		if (qt2_setregister(dev, port_priv->device_port,
812 					   UART_MCR, 0) < 0)
813 			dev_warn(&port->dev, "error from flowcontrol urb\n");
814 	}
815 	/* drop RTS and DTR */
816 	if (on)
817 		update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
818 	else
819 		update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
820 }
821 
822 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
823 {
824 	struct qt2_port_private *port_priv;
825 	u8 newMSR = (u8) *ch;
826 	unsigned long flags;
827 
828 	/* May be called from qt2_process_read_urb() for an unbound port. */
829 	port_priv = usb_get_serial_port_data(port);
830 	if (!port_priv)
831 		return;
832 
833 	spin_lock_irqsave(&port_priv->lock, flags);
834 	port_priv->shadowMSR = newMSR;
835 	spin_unlock_irqrestore(&port_priv->lock, flags);
836 
837 	if (newMSR & UART_MSR_ANY_DELTA) {
838 		/* update input line counters */
839 		if (newMSR & UART_MSR_DCTS)
840 			port->icount.cts++;
841 		if (newMSR & UART_MSR_DDSR)
842 			port->icount.dsr++;
843 		if (newMSR & UART_MSR_DDCD)
844 			port->icount.dcd++;
845 		if (newMSR & UART_MSR_TERI)
846 			port->icount.rng++;
847 
848 		wake_up_interruptible(&port->port.delta_msr_wait);
849 	}
850 }
851 
852 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
853 {
854 	struct qt2_port_private *port_priv;
855 	struct async_icount *icount;
856 	unsigned long flags;
857 	u8 newLSR = (u8) *ch;
858 
859 	/* May be called from qt2_process_read_urb() for an unbound port. */
860 	port_priv = usb_get_serial_port_data(port);
861 	if (!port_priv)
862 		return;
863 
864 	if (newLSR & UART_LSR_BI)
865 		newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
866 
867 	spin_lock_irqsave(&port_priv->lock, flags);
868 	port_priv->shadowLSR = newLSR;
869 	spin_unlock_irqrestore(&port_priv->lock, flags);
870 
871 	icount = &port->icount;
872 
873 	if (newLSR & UART_LSR_BRK_ERROR_BITS) {
874 
875 		if (newLSR & UART_LSR_BI)
876 			icount->brk++;
877 
878 		if (newLSR & UART_LSR_OE)
879 			icount->overrun++;
880 
881 		if (newLSR & UART_LSR_PE)
882 			icount->parity++;
883 
884 		if (newLSR & UART_LSR_FE)
885 			icount->frame++;
886 	}
887 
888 }
889 
890 static int qt2_write_room(struct tty_struct *tty)
891 {
892 	struct usb_serial_port *port = tty->driver_data;
893 	struct qt2_port_private *port_priv;
894 	unsigned long flags = 0;
895 	int r;
896 
897 	port_priv = usb_get_serial_port_data(port);
898 
899 	spin_lock_irqsave(&port_priv->urb_lock, flags);
900 
901 	if (port_priv->urb_in_use)
902 		r = 0;
903 	else
904 		r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
905 
906 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
907 
908 	return r;
909 }
910 
911 static int qt2_write(struct tty_struct *tty,
912 		     struct usb_serial_port *port,
913 		     const unsigned char *buf, int count)
914 {
915 	struct qt2_port_private *port_priv;
916 	struct urb *write_urb;
917 	unsigned char *data;
918 	unsigned long flags;
919 	int status;
920 	int bytes_out = 0;
921 
922 	port_priv = usb_get_serial_port_data(port);
923 
924 	if (port_priv->write_urb == NULL) {
925 		dev_err(&port->dev, "%s - no output urb\n", __func__);
926 		return 0;
927 	}
928 	write_urb = port_priv->write_urb;
929 
930 	count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
931 
932 	data = write_urb->transfer_buffer;
933 	spin_lock_irqsave(&port_priv->urb_lock, flags);
934 	if (port_priv->urb_in_use) {
935 		dev_err(&port->dev, "qt2_write - urb is in use\n");
936 		goto write_out;
937 	}
938 
939 	*data++ = QT2_CONTROL_BYTE;
940 	*data++ = QT2_CONTROL_BYTE;
941 	*data++ = port_priv->device_port;
942 	put_unaligned_le16(count, data);
943 	data += 2;
944 	memcpy(data, buf, count);
945 
946 	write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
947 
948 	status = usb_submit_urb(write_urb, GFP_ATOMIC);
949 	if (status == 0) {
950 		port_priv->urb_in_use = true;
951 		bytes_out += count;
952 	}
953 
954 write_out:
955 	spin_unlock_irqrestore(&port_priv->urb_lock, flags);
956 	return bytes_out;
957 }
958 
959 
960 static struct usb_serial_driver qt2_device = {
961 	.driver = {
962 		.owner = THIS_MODULE,
963 		.name = "quatech-serial",
964 	},
965 	.description	     = DRIVER_DESC,
966 	.id_table	     = id_table,
967 	.open		     = qt2_open,
968 	.close		     = qt2_close,
969 	.write               = qt2_write,
970 	.write_room          = qt2_write_room,
971 	.calc_num_ports      = qt2_calc_num_ports,
972 	.attach              = qt2_attach,
973 	.release             = qt2_release,
974 	.disconnect          = qt2_disconnect,
975 	.port_probe          = qt2_port_probe,
976 	.port_remove         = qt2_port_remove,
977 	.dtr_rts             = qt2_dtr_rts,
978 	.break_ctl           = qt2_break_ctl,
979 	.tiocmget            = qt2_tiocmget,
980 	.tiocmset            = qt2_tiocmset,
981 	.tiocmiwait          = usb_serial_generic_tiocmiwait,
982 	.get_icount	     = usb_serial_generic_get_icount,
983 	.get_serial          = get_serial_info,
984 	.set_termios         = qt2_set_termios,
985 };
986 
987 static struct usb_serial_driver *const serial_drivers[] = {
988 	&qt2_device, NULL
989 };
990 
991 module_usb_serial_driver(serial_drivers, id_table);
992 
993 MODULE_DESCRIPTION(DRIVER_DESC);
994 MODULE_LICENSE("GPL v2");
995