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[~andy/linux] / drivers / usb / serial / quatech2.c
1 /*
2  * usb-serial driver for Quatech USB 2 devices
3  *
4  * Copyright (C) 2012 Bill Pemberton (wfp5p@virginia.edu)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License version 2
8  * as published by the Free Software Foundation.
9  *
10  *
11  *  These devices all have only 1 bulk in and 1 bulk out that is shared
12  *  for all serial ports.
13  *
14  */
15
16 #include <asm/unaligned.h>
17 #include <linux/errno.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/tty.h>
21 #include <linux/tty_driver.h>
22 #include <linux/tty_flip.h>
23 #include <linux/module.h>
24 #include <linux/serial.h>
25 #include <linux/usb.h>
26 #include <linux/usb/serial.h>
27 #include <linux/serial_reg.h>
28 #include <linux/uaccess.h>
29
30 /* default urb timeout for usb operations */
31 #define QT2_USB_TIMEOUT USB_CTRL_SET_TIMEOUT
32
33 #define QT_OPEN_CLOSE_CHANNEL       0xca
34 #define QT_SET_GET_DEVICE           0xc2
35 #define QT_SET_GET_REGISTER         0xc0
36 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
37 #define QT_SET_ATF                  0xcd
38 #define QT_TRANSFER_IN              0xc0
39 #define QT_HW_FLOW_CONTROL_MASK     0xc5
40 #define QT_SW_FLOW_CONTROL_MASK     0xc6
41 #define QT2_BREAK_CONTROL           0xc8
42 #define QT2_GET_SET_UART            0xc1
43 #define QT2_FLUSH_DEVICE            0xc4
44 #define QT2_GET_SET_QMCR            0xe1
45 #define QT2_QMCR_RS232              0x40
46 #define QT2_QMCR_RS422              0x10
47
48 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)
49
50 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)
51
52 /* status bytes for the device */
53 #define QT2_CONTROL_BYTE    0x1b
54 #define QT2_LINE_STATUS     0x00  /* following 1 byte is line status */
55 #define QT2_MODEM_STATUS    0x01  /* following 1 byte is modem status */
56 #define QT2_XMIT_HOLD       0x02  /* following 2 bytes are ?? */
57 #define QT2_CHANGE_PORT     0x03  /* following 1 byte is port to change to */
58 #define QT2_REC_FLUSH       0x04  /* no following info */
59 #define QT2_XMIT_FLUSH      0x05  /* no following info */
60 #define QT2_CONTROL_ESCAPE  0xff  /* pass through previous 2 control bytes */
61
62 #define  MAX_BAUD_RATE              921600
63 #define  DEFAULT_BAUD_RATE          9600
64
65 #define QT2_WRITE_BUFFER_SIZE   512  /* size of write buffer */
66 #define QT2_WRITE_CONTROL_SIZE  5    /* control bytes used for a write */
67
68 #define DRIVER_DESC "Quatech 2nd gen USB to Serial Driver"
69
70 #define USB_VENDOR_ID_QUATECH   0x061d
71 #define QUATECH_SSU2_100        0xC120  /* RS232 single port */
72 #define QUATECH_DSU2_100        0xC140  /* RS232 dual port */
73 #define QUATECH_DSU2_400        0xC150  /* RS232/422/485 dual port */
74 #define QUATECH_QSU2_100        0xC160  /* RS232 four port */
75 #define QUATECH_QSU2_400        0xC170  /* RS232/422/485 four port */
76 #define QUATECH_ESU2_100        0xC1A0  /* RS232 eight port */
77 #define QUATECH_ESU2_400        0xC180  /* RS232/422/485 eight port */
78
79 struct qt2_device_detail {
80         int product_id;
81         int num_ports;
82 };
83
84 #define QT_DETAILS(prod, ports) \
85         .product_id = (prod),   \
86         .num_ports = (ports)
87
88 static const struct qt2_device_detail qt2_device_details[] = {
89         {QT_DETAILS(QUATECH_SSU2_100, 1)},
90         {QT_DETAILS(QUATECH_DSU2_400, 2)},
91         {QT_DETAILS(QUATECH_DSU2_100, 2)},
92         {QT_DETAILS(QUATECH_QSU2_400, 4)},
93         {QT_DETAILS(QUATECH_QSU2_100, 4)},
94         {QT_DETAILS(QUATECH_ESU2_400, 8)},
95         {QT_DETAILS(QUATECH_ESU2_100, 8)},
96         {QT_DETAILS(0, 0)}      /* Terminating entry */
97 };
98
99 static const struct usb_device_id id_table[] = {
100         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU2_100)},
101         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_100)},
102         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_DSU2_400)},
103         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_100)},
104         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_QSU2_400)},
105         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_100)},
106         {USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_ESU2_400)},
107         {}                      /* Terminating entry */
108 };
109 MODULE_DEVICE_TABLE(usb, id_table);
110
111 struct qt2_serial_private {
112         unsigned char current_port;  /* current port for incoming data */
113
114         struct urb      *read_urb;   /* shared among all ports */
115         char            read_buffer[512];
116 };
117
118 struct qt2_port_private {
119         bool is_open;
120         u8   device_port;
121
122         spinlock_t urb_lock;
123         bool       urb_in_use;
124         struct urb *write_urb;
125         char       write_buffer[QT2_WRITE_BUFFER_SIZE];
126
127         spinlock_t  lock;
128         u8          shadowLSR;
129         u8          shadowMSR;
130
131         wait_queue_head_t   delta_msr_wait; /* Used for TIOCMIWAIT */
132         struct async_icount icount;
133
134         struct usb_serial_port *port;
135 };
136
137 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch);
138 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch);
139 static void qt2_write_bulk_callback(struct urb *urb);
140 static void qt2_read_bulk_callback(struct urb *urb);
141
142 static void qt2_release(struct usb_serial *serial)
143 {
144         struct qt2_serial_private *serial_priv;
145
146         serial_priv = usb_get_serial_data(serial);
147
148         usb_free_urb(serial_priv->read_urb);
149         kfree(serial_priv);
150 }
151
152 static inline int calc_baud_divisor(int baudrate)
153 {
154         int divisor, rem;
155
156         divisor = MAX_BAUD_RATE / baudrate;
157         rem = MAX_BAUD_RATE % baudrate;
158         /* Round to nearest divisor */
159         if (((rem * 2) >= baudrate) && (baudrate != 110))
160                 divisor++;
161
162         return divisor;
163 }
164
165 static inline int qt2_set_port_config(struct usb_device *dev,
166                                       unsigned char port_number,
167                                       u16 baudrate, u16 lcr)
168 {
169         int divisor = calc_baud_divisor(baudrate);
170         u16 index = ((u16) (lcr << 8) | (u16) (port_number));
171
172         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
173                                QT2_GET_SET_UART, 0x40,
174                                divisor, index, NULL, 0, QT2_USB_TIMEOUT);
175 }
176
177 static inline int qt2_control_msg(struct usb_device *dev,
178                                   u8 request, u16 data, u16 index)
179 {
180         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
181                                request, 0x40, data, index,
182                                NULL, 0, QT2_USB_TIMEOUT);
183 }
184
185 static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
186 {
187         u16 x = ((u16) (data[1] << 8) | (u16) (data[0]));
188
189         return qt2_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
190 }
191
192
193 static inline int qt2_getdevice(struct usb_device *dev, u8 *data)
194 {
195         return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
196                                QT_SET_GET_DEVICE, 0xc0, 0, 0,
197                                data, 3, QT2_USB_TIMEOUT);
198 }
199
200 static inline int qt2_getregister(struct usb_device *dev,
201                                   u8 uart,
202                                   u8 reg,
203                                   u8 *data)
204 {
205         return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
206                                QT_SET_GET_REGISTER, 0xc0, reg,
207                                uart, data, sizeof(*data), QT2_USB_TIMEOUT);
208
209 }
210
211 static inline int qt2_setregister(struct usb_device *dev,
212                                   u8 uart, u8 reg, u16 data)
213 {
214         u16 value = (data << 8) | reg;
215
216         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
217                                QT_SET_GET_REGISTER, 0x40, value, uart,
218                                NULL, 0, QT2_USB_TIMEOUT);
219 }
220
221 static inline int update_mctrl(struct qt2_port_private *port_priv,
222                                unsigned int set, unsigned int clear)
223 {
224         struct usb_serial_port *port = port_priv->port;
225         struct usb_device *dev = port->serial->dev;
226         unsigned urb_value;
227         int status;
228
229         if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
230                 dev_dbg(&port->dev,
231                         "update_mctrl - DTR|RTS not being set|cleared\n");
232                 return 0;       /* no change */
233         }
234
235         clear &= ~set;  /* 'set' takes precedence over 'clear' */
236         urb_value = 0;
237         if (set & TIOCM_DTR)
238                 urb_value |= UART_MCR_DTR;
239         if (set & TIOCM_RTS)
240                 urb_value |= UART_MCR_RTS;
241
242         status = qt2_setregister(dev, port_priv->device_port, UART_MCR,
243                                  urb_value);
244         if (status < 0)
245                 dev_err(&port->dev,
246                         "update_mctrl - Error from MODEM_CTRL urb: %i\n",
247                         status);
248         return status;
249 }
250
251 static int qt2_calc_num_ports(struct usb_serial *serial)
252 {
253         struct qt2_device_detail d;
254         int i;
255
256         for (i = 0; d = qt2_device_details[i], d.product_id != 0; i++) {
257                 if (d.product_id == le16_to_cpu(serial->dev->descriptor.idProduct))
258                         return d.num_ports;
259         }
260
261         /* we didn't recognize the device */
262         dev_err(&serial->dev->dev,
263                  "don't know the number of ports, assuming 1\n");
264
265         return 1;
266 }
267
268 static void qt2_set_termios(struct tty_struct *tty,
269                             struct usb_serial_port *port,
270                             struct ktermios *old_termios)
271 {
272         struct usb_device *dev = port->serial->dev;
273         struct qt2_port_private *port_priv;
274         struct ktermios *termios = &tty->termios;
275         u16 baud;
276         unsigned int cflag = termios->c_cflag;
277         u16 new_lcr = 0;
278         int status;
279
280         port_priv = usb_get_serial_port_data(port);
281
282         if (cflag & PARENB) {
283                 if (cflag & PARODD)
284                         new_lcr |= UART_LCR_PARITY;
285                 else
286                         new_lcr |= SERIAL_EVEN_PARITY;
287         }
288
289         switch (cflag & CSIZE) {
290         case CS5:
291                 new_lcr |= UART_LCR_WLEN5;
292                 break;
293         case CS6:
294                 new_lcr |= UART_LCR_WLEN6;
295                 break;
296         case CS7:
297                 new_lcr |= UART_LCR_WLEN7;
298                 break;
299         default:
300         case CS8:
301                 new_lcr |= UART_LCR_WLEN8;
302                 break;
303         }
304
305         baud = tty_get_baud_rate(tty);
306         if (!baud)
307                 baud = 9600;
308
309         status = qt2_set_port_config(dev, port_priv->device_port, baud,
310                                      new_lcr);
311         if (status < 0)
312                 dev_err(&port->dev, "%s - qt2_set_port_config failed: %i\n",
313                         __func__, status);
314
315         if (cflag & CRTSCTS)
316                 status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
317                                          SERIAL_CRTSCTS,
318                                          port_priv->device_port);
319         else
320                 status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
321                                          0, port_priv->device_port);
322         if (status < 0)
323                 dev_err(&port->dev, "%s - set HW flow control failed: %i\n",
324                         __func__, status);
325
326         if (I_IXOFF(tty) || I_IXON(tty)) {
327                 u16 x = ((u16) (START_CHAR(tty) << 8) | (u16) (STOP_CHAR(tty)));
328
329                 status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
330                                          x, port_priv->device_port);
331         } else
332                 status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
333                                          0, port_priv->device_port);
334
335         if (status < 0)
336                 dev_err(&port->dev, "%s - set SW flow control failed: %i\n",
337                         __func__, status);
338
339 }
340
341 static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port)
342 {
343         struct usb_serial *serial;
344         struct qt2_port_private *port_priv;
345         u8 *data;
346         u16 device_port;
347         int status;
348         unsigned long flags;
349
350         device_port = (u16) (port->number - port->serial->minor);
351
352         serial = port->serial;
353
354         port_priv = usb_get_serial_port_data(port);
355
356         /* set the port to RS232 mode */
357         status = qt2_control_msg(serial->dev, QT2_GET_SET_QMCR,
358                                  QT2_QMCR_RS232, device_port);
359         if (status < 0) {
360                 dev_err(&port->dev,
361                         "%s failed to set RS232 mode for port %i error %i\n",
362                         __func__, device_port, status);
363                 return status;
364         }
365
366         data = kzalloc(2, GFP_KERNEL);
367         if (!data)
368                 return -ENOMEM;
369
370         /* open the port */
371         status = usb_control_msg(serial->dev,
372                                  usb_rcvctrlpipe(serial->dev, 0),
373                                  QT_OPEN_CLOSE_CHANNEL,
374                                  0xc0, 0,
375                                  device_port, data, 2, QT2_USB_TIMEOUT);
376
377         if (status < 0) {
378                 dev_err(&port->dev, "%s - open port failed %i", __func__,
379                         status);
380                 kfree(data);
381                 return status;
382         }
383
384         spin_lock_irqsave(&port_priv->lock, flags);
385         port_priv->shadowLSR = data[0];
386         port_priv->shadowMSR = data[1];
387         spin_unlock_irqrestore(&port_priv->lock, flags);
388
389         kfree(data);
390
391         /* set to default speed and 8bit word size */
392         status = qt2_set_port_config(serial->dev, device_port,
393                                      DEFAULT_BAUD_RATE, UART_LCR_WLEN8);
394         if (status < 0) {
395                 dev_err(&port->dev,
396                         "%s - initial setup failed for port %i (%i)\n",
397                         __func__, port->number, device_port);
398                 return status;
399         }
400
401         port_priv->is_open = true;
402         port_priv->device_port = (u8) device_port;
403
404         if (tty)
405                 qt2_set_termios(tty, port, &tty->termios);
406
407         return 0;
408
409 }
410
411 static void qt2_close(struct usb_serial_port *port)
412 {
413         struct usb_serial *serial;
414         struct qt2_port_private *port_priv;
415         unsigned long flags;
416         int i;
417
418         serial = port->serial;
419         port_priv = usb_get_serial_port_data(port);
420
421         port_priv->is_open = false;
422
423         spin_lock_irqsave(&port_priv->urb_lock, flags);
424         usb_kill_urb(port_priv->write_urb);
425         port_priv->urb_in_use = false;
426         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
427
428         mutex_lock(&port->serial->disc_mutex);
429         if (port->serial->disconnected) {
430                 mutex_unlock(&port->serial->disc_mutex);
431                 return;
432         }
433
434         /* flush the port transmit buffer */
435         i = usb_control_msg(serial->dev,
436                             usb_rcvctrlpipe(serial->dev, 0),
437                             QT2_FLUSH_DEVICE, 0x40, 1,
438                             port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
439
440         if (i < 0)
441                 dev_err(&port->dev, "%s - transmit buffer flush failed: %i\n",
442                         __func__, i);
443
444         /* flush the port receive buffer */
445         i = usb_control_msg(serial->dev,
446                             usb_rcvctrlpipe(serial->dev, 0),
447                             QT2_FLUSH_DEVICE, 0x40, 0,
448                             port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
449
450         if (i < 0)
451                 dev_err(&port->dev, "%s - receive buffer flush failed: %i\n",
452                         __func__, i);
453
454         /* close the port */
455         i = usb_control_msg(serial->dev,
456                             usb_sndctrlpipe(serial->dev, 0),
457                             QT_OPEN_CLOSE_CHANNEL,
458                             0x40, 0,
459                             port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
460
461         if (i < 0)
462                 dev_err(&port->dev, "%s - close port failed %i\n",
463                         __func__, i);
464
465         mutex_unlock(&port->serial->disc_mutex);
466 }
467
468 static void qt2_disconnect(struct usb_serial *serial)
469 {
470         struct qt2_serial_private *serial_priv = usb_get_serial_data(serial);
471
472         usb_kill_urb(serial_priv->read_urb);
473 }
474
475 static int get_serial_info(struct usb_serial_port *port,
476                            struct serial_struct __user *retinfo)
477 {
478         struct serial_struct tmp;
479
480         if (!retinfo)
481                 return -EFAULT;
482
483         memset(&tmp, 0, sizeof(tmp));
484         tmp.line                = port->serial->minor;
485         tmp.port                = 0;
486         tmp.irq                 = 0;
487         tmp.flags               = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
488         tmp.xmit_fifo_size      = port->bulk_out_size;
489         tmp.baud_base           = 9600;
490         tmp.close_delay         = 5*HZ;
491         tmp.closing_wait        = 30*HZ;
492
493         if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
494                 return -EFAULT;
495         return 0;
496 }
497
498 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
499 {
500         struct qt2_port_private *priv = usb_get_serial_port_data(port);
501         struct async_icount prev, cur;
502         unsigned long flags;
503
504         spin_lock_irqsave(&priv->lock, flags);
505         prev = priv->icount;
506         spin_unlock_irqrestore(&priv->lock, flags);
507
508         while (1) {
509                 wait_event_interruptible(priv->delta_msr_wait,
510                                          ((priv->icount.rng != prev.rng) ||
511                                           (priv->icount.dsr != prev.dsr) ||
512                                           (priv->icount.dcd != prev.dcd) ||
513                                           (priv->icount.cts != prev.cts)));
514
515                 if (signal_pending(current))
516                         return -ERESTARTSYS;
517
518                 spin_lock_irqsave(&priv->lock, flags);
519                 cur = priv->icount;
520                 spin_unlock_irqrestore(&priv->lock, flags);
521
522                 if ((prev.rng == cur.rng) &&
523                     (prev.dsr == cur.dsr) &&
524                     (prev.dcd == cur.dcd) &&
525                     (prev.cts == cur.cts))
526                         return -EIO;
527
528                 if ((arg & TIOCM_RNG && (prev.rng != cur.rng)) ||
529                     (arg & TIOCM_DSR && (prev.dsr != cur.dsr)) ||
530                     (arg & TIOCM_CD && (prev.dcd != cur.dcd)) ||
531                     (arg & TIOCM_CTS && (prev.cts != cur.cts)))
532                         return 0;
533         }
534         return 0;
535 }
536
537 static int qt2_get_icount(struct tty_struct *tty,
538                           struct serial_icounter_struct *icount)
539 {
540         struct usb_serial_port *port = tty->driver_data;
541         struct qt2_port_private *priv = usb_get_serial_port_data(port);
542         struct async_icount cnow = priv->icount;
543
544         icount->cts = cnow.cts;
545         icount->dsr = cnow.dsr;
546         icount->rng = cnow.rng;
547         icount->dcd = cnow.dcd;
548         icount->rx = cnow.rx;
549         icount->tx = cnow.tx;
550         icount->frame = cnow.frame;
551         icount->overrun = cnow.overrun;
552         icount->parity = cnow.parity;
553         icount->brk = cnow.brk;
554         icount->buf_overrun = cnow.buf_overrun;
555
556         return 0;
557 }
558
559 static int qt2_ioctl(struct tty_struct *tty,
560                      unsigned int cmd, unsigned long arg)
561 {
562         struct usb_serial_port *port = tty->driver_data;
563
564         switch (cmd) {
565         case TIOCGSERIAL:
566                 return get_serial_info(port,
567                                        (struct serial_struct __user *)arg);
568
569         case TIOCMIWAIT:
570                 return wait_modem_info(port, arg);
571
572         default:
573                 break;
574         }
575
576         return -ENOIOCTLCMD;
577 }
578
579 static void qt2_process_status(struct usb_serial_port *port, unsigned char *ch)
580 {
581         switch (*ch) {
582         case QT2_LINE_STATUS:
583                 qt2_update_lsr(port, ch + 1);
584                 break;
585         case QT2_MODEM_STATUS:
586                 qt2_update_msr(port, ch + 1);
587                 break;
588         }
589 }
590
591 /* not needed, kept to document functionality */
592 static void qt2_process_xmit_empty(struct usb_serial_port *port,
593                                    unsigned char *ch)
594 {
595         int bytes_written;
596
597         bytes_written = (int)(*ch) + (int)(*(ch + 1) << 4);
598 }
599
600 /* not needed, kept to document functionality */
601 static void qt2_process_flush(struct usb_serial_port *port, unsigned char *ch)
602 {
603         return;
604 }
605
606 void qt2_process_read_urb(struct urb *urb)
607 {
608         struct usb_serial *serial;
609         struct qt2_serial_private *serial_priv;
610         struct usb_serial_port *port;
611         struct qt2_port_private *port_priv;
612         bool escapeflag;
613         unsigned char *ch;
614         int i;
615         unsigned char newport;
616         int len = urb->actual_length;
617
618         if (!len)
619                 return;
620
621         ch = urb->transfer_buffer;
622         serial = urb->context;
623         serial_priv = usb_get_serial_data(serial);
624         port = serial->port[serial_priv->current_port];
625         port_priv = usb_get_serial_port_data(port);
626
627         for (i = 0; i < urb->actual_length; i++) {
628                 ch = (unsigned char *)urb->transfer_buffer + i;
629                 if ((i <= (len - 3)) &&
630                     (*ch == QT2_CONTROL_BYTE) &&
631                     (*(ch + 1) == QT2_CONTROL_BYTE)) {
632                         escapeflag = false;
633                         switch (*(ch + 2)) {
634                         case QT2_LINE_STATUS:
635                         case QT2_MODEM_STATUS:
636                                 if (i > (len - 4)) {
637                                         dev_warn(&port->dev,
638                                                  "%s - status message too short\n",
639                                                 __func__);
640                                         break;
641                                 }
642                                 qt2_process_status(port, ch + 2);
643                                 i += 3;
644                                 escapeflag = true;
645                                 break;
646                         case QT2_XMIT_HOLD:
647                                 if (i > (len - 5)) {
648                                         dev_warn(&port->dev,
649                                                  "%s - xmit_empty message too short\n",
650                                                  __func__);
651                                         break;
652                                 }
653                                 qt2_process_xmit_empty(port, ch + 3);
654                                 i += 4;
655                                 escapeflag = true;
656                                 break;
657                         case QT2_CHANGE_PORT:
658                                 if (i > (len - 4)) {
659                                         dev_warn(&port->dev,
660                                                  "%s - change_port message too short\n",
661                                                  __func__);
662                                         break;
663                                 }
664                                 tty_flip_buffer_push(&port->port);
665
666                                 newport = *(ch + 3);
667
668                                 if (newport > serial->num_ports) {
669                                         dev_err(&port->dev,
670                                                 "%s - port change to invalid port: %i\n",
671                                                 __func__, newport);
672                                         break;
673                                 }
674
675                                 serial_priv->current_port = newport;
676                                 port = serial->port[serial_priv->current_port];
677                                 port_priv = usb_get_serial_port_data(port);
678                                 i += 3;
679                                 escapeflag = true;
680                                 break;
681                         case QT2_REC_FLUSH:
682                         case QT2_XMIT_FLUSH:
683                                 qt2_process_flush(port, ch + 2);
684                                 i += 2;
685                                 escapeflag = true;
686                                 break;
687                         case QT2_CONTROL_ESCAPE:
688                                 tty_buffer_request_room(&port->port, 2);
689                                 tty_insert_flip_string(&port->port, ch, 2);
690                                 i += 2;
691                                 escapeflag = true;
692                                 break;
693                         default:
694                                 dev_warn(&port->dev,
695                                          "%s - unsupported command %i\n",
696                                          __func__, *(ch + 2));
697                                 break;
698                         }
699                         if (escapeflag)
700                                 continue;
701                 }
702
703                 tty_buffer_request_room(&port->port, 1);
704                 tty_insert_flip_string(&port->port, ch, 1);
705         }
706
707         tty_flip_buffer_push(&port->port);
708 }
709
710 static void qt2_write_bulk_callback(struct urb *urb)
711 {
712         struct usb_serial_port *port;
713         struct qt2_port_private *port_priv;
714
715         port = urb->context;
716         port_priv = usb_get_serial_port_data(port);
717
718         spin_lock(&port_priv->urb_lock);
719
720         port_priv->urb_in_use = false;
721         usb_serial_port_softint(port);
722
723         spin_unlock(&port_priv->urb_lock);
724
725 }
726
727 static void qt2_read_bulk_callback(struct urb *urb)
728 {
729         struct usb_serial *serial = urb->context;
730         int status;
731
732         if (urb->status) {
733                 dev_warn(&serial->dev->dev,
734                          "%s - non-zero urb status: %i\n", __func__,
735                          urb->status);
736                 return;
737         }
738
739         qt2_process_read_urb(urb);
740
741         status = usb_submit_urb(urb, GFP_ATOMIC);
742         if (status != 0)
743                 dev_err(&serial->dev->dev,
744                         "%s - resubmit read urb failed: %i\n",
745                         __func__, status);
746 }
747
748 static int qt2_setup_urbs(struct usb_serial *serial)
749 {
750         struct usb_serial_port *port0;
751         struct qt2_serial_private *serial_priv;
752         int status;
753
754         port0 = serial->port[0];
755
756         serial_priv = usb_get_serial_data(serial);
757         serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
758         if (!serial_priv->read_urb) {
759                 dev_err(&serial->dev->dev, "No free urbs available\n");
760                 return -ENOMEM;
761         }
762
763         usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
764                           usb_rcvbulkpipe(serial->dev,
765                                           port0->bulk_in_endpointAddress),
766                           serial_priv->read_buffer,
767                           sizeof(serial_priv->read_buffer),
768                           qt2_read_bulk_callback, serial);
769
770         status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
771         if (status != 0) {
772                 dev_err(&serial->dev->dev,
773                         "%s - submit read urb failed %i\n", __func__, status);
774                 usb_free_urb(serial_priv->read_urb);
775                 return status;
776         }
777
778         return 0;
779 }
780
781 static int qt2_attach(struct usb_serial *serial)
782 {
783         struct qt2_serial_private *serial_priv;
784         int status;
785
786         /* power on unit */
787         status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
788                                  0xc2, 0x40, 0x8000, 0, NULL, 0,
789                                  QT2_USB_TIMEOUT);
790         if (status < 0) {
791                 dev_err(&serial->dev->dev,
792                         "%s - failed to power on unit: %i\n", __func__, status);
793                 return status;
794         }
795
796         serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
797         if (!serial_priv) {
798                 dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
799                 return -ENOMEM;
800         }
801
802         usb_set_serial_data(serial, serial_priv);
803
804         status = qt2_setup_urbs(serial);
805         if (status != 0)
806                 goto attach_failed;
807
808         return 0;
809
810 attach_failed:
811         kfree(serial_priv);
812         return status;
813 }
814
815 static int qt2_port_probe(struct usb_serial_port *port)
816 {
817         struct usb_serial *serial = port->serial;
818         struct qt2_port_private *port_priv;
819         u8 bEndpointAddress;
820
821         port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
822         if (!port_priv)
823                 return -ENOMEM;
824
825         spin_lock_init(&port_priv->lock);
826         spin_lock_init(&port_priv->urb_lock);
827         init_waitqueue_head(&port_priv->delta_msr_wait);
828         port_priv->port = port;
829
830         port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
831         if (!port_priv->write_urb) {
832                 kfree(port_priv);
833                 return -ENOMEM;
834         }
835         bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
836         usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
837                                 usb_sndbulkpipe(serial->dev, bEndpointAddress),
838                                 port_priv->write_buffer,
839                                 sizeof(port_priv->write_buffer),
840                                 qt2_write_bulk_callback, port);
841
842         usb_set_serial_port_data(port, port_priv);
843
844         return 0;
845 }
846
847 static int qt2_port_remove(struct usb_serial_port *port)
848 {
849         struct qt2_port_private *port_priv;
850
851         port_priv = usb_get_serial_port_data(port);
852         usb_free_urb(port_priv->write_urb);
853         kfree(port_priv);
854
855         return 0;
856 }
857
858 static int qt2_tiocmget(struct tty_struct *tty)
859 {
860         struct usb_serial_port *port = tty->driver_data;
861         struct usb_device *dev = port->serial->dev;
862         struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
863         u8 *d;
864         int r;
865
866         d = kzalloc(2, GFP_KERNEL);
867         if (!d)
868                 return -ENOMEM;
869
870         r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
871         if (r < 0)
872                 goto mget_out;
873
874         r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
875         if (r < 0)
876                 goto mget_out;
877
878         r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
879             (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
880             (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
881             (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
882             (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
883             (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
884
885 mget_out:
886         kfree(d);
887         return r;
888 }
889
890 static int qt2_tiocmset(struct tty_struct *tty,
891                         unsigned int set, unsigned int clear)
892 {
893         struct qt2_port_private *port_priv;
894
895         port_priv = usb_get_serial_port_data(tty->driver_data);
896         return update_mctrl(port_priv, set, clear);
897 }
898
899 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
900 {
901         struct usb_serial_port *port = tty->driver_data;
902         struct qt2_port_private *port_priv;
903         int status;
904         u16 val;
905
906         port_priv = usb_get_serial_port_data(port);
907
908         if (!port_priv->is_open) {
909                 dev_err(&port->dev,
910                         "%s - port is not open\n", __func__);
911                 return;
912         }
913
914         val = (break_state == -1) ? 1 : 0;
915
916         status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
917                                  val, port_priv->device_port);
918         if (status < 0)
919                 dev_warn(&port->dev,
920                          "%s - failed to send control message: %i\n", __func__,
921                          status);
922 }
923
924
925
926 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
927 {
928         struct usb_device *dev = port->serial->dev;
929         struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
930
931         /* Disable flow control */
932         if (!on) {
933                 if (qt2_setregister(dev, port_priv->device_port,
934                                            UART_MCR, 0) < 0)
935                         dev_warn(&port->dev, "error from flowcontrol urb\n");
936         }
937         /* drop RTS and DTR */
938         if (on)
939                 update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
940         else
941                 update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
942 }
943
944 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
945 {
946         struct qt2_port_private *port_priv;
947         u8 newMSR = (u8) *ch;
948         unsigned long flags;
949
950         port_priv = usb_get_serial_port_data(port);
951
952         spin_lock_irqsave(&port_priv->lock, flags);
953         port_priv->shadowMSR = newMSR;
954         spin_unlock_irqrestore(&port_priv->lock, flags);
955
956         if (newMSR & UART_MSR_ANY_DELTA) {
957                 /* update input line counters */
958                 if (newMSR & UART_MSR_DCTS)
959                         port_priv->icount.cts++;
960
961                 if (newMSR & UART_MSR_DDSR)
962                         port_priv->icount.dsr++;
963
964                 if (newMSR & UART_MSR_DDCD)
965                         port_priv->icount.dcd++;
966
967                 if (newMSR & UART_MSR_TERI)
968                         port_priv->icount.rng++;
969
970                 wake_up_interruptible(&port_priv->delta_msr_wait);
971         }
972 }
973
974 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
975 {
976         struct qt2_port_private *port_priv;
977         struct async_icount *icount;
978         unsigned long flags;
979         u8 newLSR = (u8) *ch;
980
981         port_priv = usb_get_serial_port_data(port);
982
983         if (newLSR & UART_LSR_BI)
984                 newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
985
986         spin_lock_irqsave(&port_priv->lock, flags);
987         port_priv->shadowLSR = newLSR;
988         spin_unlock_irqrestore(&port_priv->lock, flags);
989
990         icount = &port_priv->icount;
991
992         if (newLSR & UART_LSR_BRK_ERROR_BITS) {
993
994                 if (newLSR & UART_LSR_BI)
995                         icount->brk++;
996
997                 if (newLSR & UART_LSR_OE)
998                         icount->overrun++;
999
1000                 if (newLSR & UART_LSR_PE)
1001                         icount->parity++;
1002
1003                 if (newLSR & UART_LSR_FE)
1004                         icount->frame++;
1005         }
1006
1007 }
1008
1009 static int qt2_write_room(struct tty_struct *tty)
1010 {
1011         struct usb_serial_port *port = tty->driver_data;
1012         struct qt2_port_private *port_priv;
1013         unsigned long flags = 0;
1014         int r;
1015
1016         port_priv = usb_get_serial_port_data(port);
1017
1018         spin_lock_irqsave(&port_priv->urb_lock, flags);
1019
1020         if (port_priv->urb_in_use)
1021                 r = 0;
1022         else
1023                 r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
1024
1025         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1026
1027         return r;
1028 }
1029
1030 static int qt2_write(struct tty_struct *tty,
1031                      struct usb_serial_port *port,
1032                      const unsigned char *buf, int count)
1033 {
1034         struct qt2_port_private *port_priv;
1035         struct urb *write_urb;
1036         unsigned char *data;
1037         unsigned long flags;
1038         int status;
1039         int bytes_out = 0;
1040
1041         port_priv = usb_get_serial_port_data(port);
1042
1043         if (port_priv->write_urb == NULL) {
1044                 dev_err(&port->dev, "%s - no output urb\n", __func__);
1045                 return 0;
1046         }
1047         write_urb = port_priv->write_urb;
1048
1049         count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
1050
1051         data = write_urb->transfer_buffer;
1052         spin_lock_irqsave(&port_priv->urb_lock, flags);
1053         if (port_priv->urb_in_use == true) {
1054                 dev_err(&port->dev, "qt2_write - urb is in use\n");
1055                 goto write_out;
1056         }
1057
1058         *data++ = QT2_CONTROL_BYTE;
1059         *data++ = QT2_CONTROL_BYTE;
1060         *data++ = port_priv->device_port;
1061         put_unaligned_le16(count, data);
1062         data += 2;
1063         memcpy(data, buf, count);
1064
1065         write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
1066
1067         status = usb_submit_urb(write_urb, GFP_ATOMIC);
1068         if (status == 0) {
1069                 port_priv->urb_in_use = true;
1070                 bytes_out += count;
1071         }
1072
1073 write_out:
1074         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1075         return bytes_out;
1076 }
1077
1078
1079 static struct usb_serial_driver qt2_device = {
1080         .driver = {
1081                 .owner = THIS_MODULE,
1082                 .name = "quatech-serial",
1083         },
1084         .description         = DRIVER_DESC,
1085         .id_table            = id_table,
1086         .open                = qt2_open,
1087         .close               = qt2_close,
1088         .write               = qt2_write,
1089         .write_room          = qt2_write_room,
1090         .calc_num_ports      = qt2_calc_num_ports,
1091         .attach              = qt2_attach,
1092         .release             = qt2_release,
1093         .disconnect          = qt2_disconnect,
1094         .port_probe          = qt2_port_probe,
1095         .port_remove         = qt2_port_remove,
1096         .dtr_rts             = qt2_dtr_rts,
1097         .break_ctl           = qt2_break_ctl,
1098         .tiocmget            = qt2_tiocmget,
1099         .tiocmset            = qt2_tiocmset,
1100         .get_icount          = qt2_get_icount,
1101         .ioctl               = qt2_ioctl,
1102         .set_termios         = qt2_set_termios,
1103 };
1104
1105 static struct usb_serial_driver *const serial_drivers[] = {
1106         &qt2_device, NULL
1107 };
1108
1109 module_usb_serial_driver(serial_drivers, id_table);
1110
1111 MODULE_DESCRIPTION(DRIVER_DESC);
1112 MODULE_LICENSE("GPL");