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         struct tty_struct *tty;
 613         bool escapeflag;
 614         unsigned char *ch;
 615         int i;
 616         unsigned char newport;
 617         int len = urb->actual_length;
 618
 619         if (!len)
 620                 return;
 621
 622         ch = urb->transfer_buffer;
 623         tty = NULL;
 624         serial = urb->context;
 625         serial_priv = usb_get_serial_data(serial);
 626         port = serial->port[serial_priv->current_port];
 627         port_priv = usb_get_serial_port_data(port);
 628
 629         if (port_priv->is_open)
 630                 tty = tty_port_tty_get(&port->port);
 631
 632         for (i = 0; i < urb->actual_length; i++) {
 633                 ch = (unsigned char *)urb->transfer_buffer + i;
 634                 if ((i <= (len - 3)) &&
 635                     (*ch == QT2_CONTROL_BYTE) &&
 636                     (*(ch + 1) == QT2_CONTROL_BYTE)) {
 637                         escapeflag = false;
 638                         switch (*(ch + 2)) {
 639                         case QT2_LINE_STATUS:
 640                         case QT2_MODEM_STATUS:
 641                                 if (i > (len - 4)) {
 642                                         dev_warn(&port->dev,
 643                                                  "%s - status message too short\n",
 644                                                 __func__);
 645                                         break;
 646                                 }
 647                                 qt2_process_status(port, ch + 2);
 648                                 i += 3;
 649                                 escapeflag = true;
 650                                 break;
 651                         case QT2_XMIT_HOLD:
 652                                 if (i > (len - 5)) {
 653                                         dev_warn(&port->dev,
 654                                                  "%s - xmit_empty message too short\n",
 655                                                  __func__);
 656                                         break;
 657                                 }
 658                                 qt2_process_xmit_empty(port, ch + 3);
 659                                 i += 4;
 660                                 escapeflag = true;
 661                                 break;
 662                         case QT2_CHANGE_PORT:
 663                                 if (i > (len - 4)) {
 664                                         dev_warn(&port->dev,
 665                                                  "%s - change_port message too short\n",
 666                                                  __func__);
 667                                         break;
 668                                 }
 669                                 if (tty) {
 670                                         tty_flip_buffer_push(tty);
 671                                         tty_kref_put(tty);
 672                                 }
 673
 674                                 newport = *(ch + 3);
 675
 676                                 if (newport > serial->num_ports) {
 677                                         dev_err(&port->dev,
 678                                                 "%s - port change to invalid port: %i\n",
 679                                                 __func__, newport);
 680                                         break;
 681                                 }
 682
 683                                 serial_priv->current_port = newport;
 684                                 port = serial->port[serial_priv->current_port];
 685                                 port_priv = usb_get_serial_port_data(port);
 686                                 if (port_priv->is_open)
 687                                         tty = tty_port_tty_get(&port->port);
 688                                 else
 689                                         tty = NULL;
 690                                 i += 3;
 691                                 escapeflag = true;
 692                                 break;
 693                         case QT2_REC_FLUSH:
 694                         case QT2_XMIT_FLUSH:
 695                                 qt2_process_flush(port, ch + 2);
 696                                 i += 2;
 697                                 escapeflag = true;
 698                                 break;
 699                         case QT2_CONTROL_ESCAPE:
 700                                 tty_buffer_request_room(tty, 2);
 701                                 tty_insert_flip_string(tty, ch, 2);
 702                                 i += 2;
 703                                 escapeflag = true;
 704                                 break;
 705                         default:
 706                                 dev_warn(&port->dev,
 707                                          "%s - unsupported command %i\n",
 708                                          __func__, *(ch + 2));
 709                                 break;
 710                         }
 711                         if (escapeflag)
 712                                 continue;
 713                 }
 714
 715                 if (tty) {
 716                         tty_buffer_request_room(tty, 1);
 717                         tty_insert_flip_string(tty, ch, 1);
 718                 }
 719         }
 720
 721         if (tty) {
 722                 tty_flip_buffer_push(tty);
 723                 tty_kref_put(tty);
 724         }
 725 }
 726
 727 static void qt2_write_bulk_callback(struct urb *urb)
 728 {
 729         struct usb_serial_port *port;
 730         struct qt2_port_private *port_priv;
 731
 732         port = urb->context;
 733         port_priv = usb_get_serial_port_data(port);
 734
 735         spin_lock(&port_priv->urb_lock);
 736
 737         port_priv->urb_in_use = false;
 738         usb_serial_port_softint(port);
 739
 740         spin_unlock(&port_priv->urb_lock);
 741
 742 }
 743
 744 static void qt2_read_bulk_callback(struct urb *urb)
 745 {
 746         struct usb_serial *serial = urb->context;
 747         int status;
 748
 749         if (urb->status) {
 750                 dev_warn(&serial->dev->dev,
 751                          "%s - non-zero urb status: %i\n", __func__,
 752                          urb->status);
 753                 return;
 754         }
 755
 756         qt2_process_read_urb(urb);
 757
 758         status = usb_submit_urb(urb, GFP_ATOMIC);
 759         if (status != 0)
 760                 dev_err(&serial->dev->dev,
 761                         "%s - resubmit read urb failed: %i\n",
 762                         __func__, status);
 763 }
 764
 765 static int qt2_setup_urbs(struct usb_serial *serial)
 766 {
 767         struct usb_serial_port *port0;
 768         struct qt2_serial_private *serial_priv;
 769         int status;
 770
 771         port0 = serial->port[0];
 772
 773         serial_priv = usb_get_serial_data(serial);
 774         serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
 775         if (!serial_priv->read_urb) {
 776                 dev_err(&serial->dev->dev, "No free urbs available\n");
 777                 return -ENOMEM;
 778         }
 779
 780         usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
 781                           usb_rcvbulkpipe(serial->dev,
 782                                           port0->bulk_in_endpointAddress),
 783                           serial_priv->read_buffer,
 784                           sizeof(serial_priv->read_buffer),
 785                           qt2_read_bulk_callback, serial);
 786
 787         status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
 788         if (status != 0) {
 789                 dev_err(&serial->dev->dev,
 790                         "%s - submit read urb failed %i\n", __func__, status);
 791                 usb_free_urb(serial_priv->read_urb);
 792                 return status;
 793         }
 794
 795         return 0;
 796 }
 797
 798 static int qt2_attach(struct usb_serial *serial)
 799 {
 800         struct qt2_serial_private *serial_priv;
 801         int status;
 802
 803         /* power on unit */
 804         status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 805                                  0xc2, 0x40, 0x8000, 0, NULL, 0,
 806                                  QT2_USB_TIMEOUT);
 807         if (status < 0) {
 808                 dev_err(&serial->dev->dev,
 809                         "%s - failed to power on unit: %i\n", __func__, status);
 810                 return status;
 811         }
 812
 813         serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
 814         if (!serial_priv) {
 815                 dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
 816                 return -ENOMEM;
 817         }
 818
 819         usb_set_serial_data(serial, serial_priv);
 820
 821         status = qt2_setup_urbs(serial);
 822         if (status != 0)
 823                 goto attach_failed;
 824
 825         return 0;
 826
 827 attach_failed:
 828         kfree(serial_priv);
 829         return status;
 830 }
 831
 832 static int qt2_port_probe(struct usb_serial_port *port)
 833 {
 834         struct usb_serial *serial = port->serial;
 835         struct qt2_port_private *port_priv;
 836         u8 bEndpointAddress;
 837
 838         port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
 839         if (!port_priv)
 840                 return -ENOMEM;
 841
 842         spin_lock_init(&port_priv->lock);
 843         spin_lock_init(&port_priv->urb_lock);
 844         init_waitqueue_head(&port_priv->delta_msr_wait);
 845         port_priv->port = port;
 846
 847         port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
 848         if (!port_priv->write_urb) {
 849                 kfree(port_priv);
 850                 return -ENOMEM;
 851         }
 852         bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
 853         usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
 854                                 usb_sndbulkpipe(serial->dev, bEndpointAddress),
 855                                 port_priv->write_buffer,
 856                                 sizeof(port_priv->write_buffer),
 857                                 qt2_write_bulk_callback, port);
 858
 859         usb_set_serial_port_data(port, port_priv);
 860
 861         return 0;
 862 }
 863
 864 static int qt2_port_remove(struct usb_serial_port *port)
 865 {
 866         struct qt2_port_private *port_priv;
 867
 868         port_priv = usb_get_serial_port_data(port);
 869         usb_free_urb(port_priv->write_urb);
 870         kfree(port_priv);
 871
 872         return 0;
 873 }
 874
 875 static int qt2_tiocmget(struct tty_struct *tty)
 876 {
 877         struct usb_serial_port *port = tty->driver_data;
 878         struct usb_device *dev = port->serial->dev;
 879         struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
 880         u8 *d;
 881         int r;
 882
 883         d = kzalloc(2, GFP_KERNEL);
 884         if (!d)
 885                 return -ENOMEM;
 886
 887         r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
 888         if (r < 0)
 889                 goto mget_out;
 890
 891         r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
 892         if (r < 0)
 893                 goto mget_out;
 894
 895         r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
 896             (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
 897             (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
 898             (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
 899             (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
 900             (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
 901
 902 mget_out:
 903         kfree(d);
 904         return r;
 905 }
 906
 907 static int qt2_tiocmset(struct tty_struct *tty,
 908                         unsigned int set, unsigned int clear)
 909 {
 910         struct qt2_port_private *port_priv;
 911
 912         port_priv = usb_get_serial_port_data(tty->driver_data);
 913         return update_mctrl(port_priv, set, clear);
 914 }
 915
 916 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
 917 {
 918         struct usb_serial_port *port = tty->driver_data;
 919         struct qt2_port_private *port_priv;
 920         int status;
 921         u16 val;
 922
 923         port_priv = usb_get_serial_port_data(port);
 924
 925         if (!port_priv->is_open) {
 926                 dev_err(&port->dev,
 927                         "%s - port is not open\n", __func__);
 928                 return;
 929         }
 930
 931         val = (break_state == -1) ? 1 : 0;
 932
 933         status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
 934                                  val, port_priv->device_port);
 935         if (status < 0)
 936                 dev_warn(&port->dev,
 937                          "%s - failed to send control message: %i\n", __func__,
 938                          status);
 939 }
 940
 941
 942
 943 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
 944 {
 945         struct usb_device *dev = port->serial->dev;
 946         struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
 947
 948         mutex_lock(&port->serial->disc_mutex);
 949         if (!port->serial->disconnected) {
 950                 /* Disable flow control */
 951                 if (!on && qt2_setregister(dev, port_priv->device_port,
 952                                            UART_MCR, 0) < 0)
 953                         dev_warn(&port->dev, "error from flowcontrol urb\n");
 954                 /* drop RTS and DTR */
 955                 if (on)
 956                         update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
 957                 else
 958                         update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
 959         }
 960         mutex_unlock(&port->serial->disc_mutex);
 961 }
 962
 963 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
 964 {
 965         struct qt2_port_private *port_priv;
 966         u8 newMSR = (u8) *ch;
 967         unsigned long flags;
 968
 969         port_priv = usb_get_serial_port_data(port);
 970
 971         spin_lock_irqsave(&port_priv->lock, flags);
 972         port_priv->shadowMSR = newMSR;
 973         spin_unlock_irqrestore(&port_priv->lock, flags);
 974
 975         if (newMSR & UART_MSR_ANY_DELTA) {
 976                 /* update input line counters */
 977                 if (newMSR & UART_MSR_DCTS)
 978                         port_priv->icount.cts++;
 979
 980                 if (newMSR & UART_MSR_DDSR)
 981                         port_priv->icount.dsr++;
 982
 983                 if (newMSR & UART_MSR_DDCD)
 984                         port_priv->icount.dcd++;
 985
 986                 if (newMSR & UART_MSR_TERI)
 987                         port_priv->icount.rng++;
 988
 989                 wake_up_interruptible(&port_priv->delta_msr_wait);
 990         }
 991 }
 992
 993 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
 994 {
 995         struct qt2_port_private *port_priv;
 996         struct async_icount *icount;
 997         unsigned long flags;
 998         u8 newLSR = (u8) *ch;
 999
1000         port_priv = usb_get_serial_port_data(port);
1001
1002         if (newLSR & UART_LSR_BI)
1003                 newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
1004
1005         spin_lock_irqsave(&port_priv->lock, flags);
1006         port_priv->shadowLSR = newLSR;
1007         spin_unlock_irqrestore(&port_priv->lock, flags);
1008
1009         icount = &port_priv->icount;
1010
1011         if (newLSR & UART_LSR_BRK_ERROR_BITS) {
1012
1013                 if (newLSR & UART_LSR_BI)
1014                         icount->brk++;
1015
1016                 if (newLSR & UART_LSR_OE)
1017                         icount->overrun++;
1018
1019                 if (newLSR & UART_LSR_PE)
1020                         icount->parity++;
1021
1022                 if (newLSR & UART_LSR_FE)
1023                         icount->frame++;
1024         }
1025
1026 }
1027
1028 static int qt2_write_room(struct tty_struct *tty)
1029 {
1030         struct usb_serial_port *port = tty->driver_data;
1031         struct qt2_port_private *port_priv;
1032         unsigned long flags = 0;
1033         int r;
1034
1035         port_priv = usb_get_serial_port_data(port);
1036
1037         spin_lock_irqsave(&port_priv->urb_lock, flags);
1038
1039         if (port_priv->urb_in_use)
1040                 r = 0;
1041         else
1042                 r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
1043
1044         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1045
1046         return r;
1047 }
1048
1049 static int qt2_write(struct tty_struct *tty,
1050                      struct usb_serial_port *port,
1051                      const unsigned char *buf, int count)
1052 {
1053         struct qt2_port_private *port_priv;
1054         struct urb *write_urb;
1055         unsigned char *data;
1056         unsigned long flags;
1057         int status;
1058         int bytes_out = 0;
1059
1060         port_priv = usb_get_serial_port_data(port);
1061
1062         if (port_priv->write_urb == NULL) {
1063                 dev_err(&port->dev, "%s - no output urb\n", __func__);
1064                 return 0;
1065         }
1066         write_urb = port_priv->write_urb;
1067
1068         count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
1069
1070         data = write_urb->transfer_buffer;
1071         spin_lock_irqsave(&port_priv->urb_lock, flags);
1072         if (port_priv->urb_in_use == true) {
1073                 dev_err(&port->dev, "qt2_write - urb is in use\n");
1074                 goto write_out;
1075         }
1076
1077         *data++ = QT2_CONTROL_BYTE;
1078         *data++ = QT2_CONTROL_BYTE;
1079         *data++ = port_priv->device_port;
1080         put_unaligned_le16(count, data);
1081         data += 2;
1082         memcpy(data, buf, count);
1083
1084         write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
1085
1086         status = usb_submit_urb(write_urb, GFP_ATOMIC);
1087         if (status == 0) {
1088                 port_priv->urb_in_use = true;
1089                 bytes_out += count;
1090         }
1091
1092 write_out:
1093         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1094         return bytes_out;
1095 }
1096
1097
1098 static struct usb_serial_driver qt2_device = {
1099         .driver = {
1100                 .owner = THIS_MODULE,
1101                 .name = "quatech-serial",
1102         },
1103         .description         = DRIVER_DESC,
1104         .id_table            = id_table,
1105         .open                = qt2_open,
1106         .close               = qt2_close,
1107         .write               = qt2_write,
1108         .write_room          = qt2_write_room,
1109         .calc_num_ports      = qt2_calc_num_ports,
1110         .attach              = qt2_attach,
1111         .release             = qt2_release,
1112         .disconnect          = qt2_disconnect,
1113         .port_probe          = qt2_port_probe,
1114         .port_remove         = qt2_port_remove,
1115         .dtr_rts             = qt2_dtr_rts,
1116         .break_ctl           = qt2_break_ctl,
1117         .tiocmget            = qt2_tiocmget,
1118         .tiocmset            = qt2_tiocmset,
1119         .get_icount          = qt2_get_icount,
1120         .ioctl               = qt2_ioctl,
1121         .set_termios         = qt2_set_termios,
1122 };
1123
1124 static struct usb_serial_driver *const serial_drivers[] = {
1125         &qt2_device, NULL
1126 };
1127
1128 module_usb_serial_driver(serial_drivers, id_table);
1129
1130 MODULE_DESCRIPTION(DRIVER_DESC);
1131 MODULE_LICENSE("GPL");