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         struct async_icount icount;
 132
 133         struct usb_serial_port *port;
 134 };
 135
 136 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch);
 137 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch);
 138 static void qt2_write_bulk_callback(struct urb *urb);
 139 static void qt2_read_bulk_callback(struct urb *urb);
 140
 141 static void qt2_release(struct usb_serial *serial)
 142 {
 143         struct qt2_serial_private *serial_priv;
 144
 145         serial_priv = usb_get_serial_data(serial);
 146
 147         usb_free_urb(serial_priv->read_urb);
 148         kfree(serial_priv);
 149 }
 150
 151 static inline int calc_baud_divisor(int baudrate)
 152 {
 153         int divisor, rem;
 154
 155         divisor = MAX_BAUD_RATE / baudrate;
 156         rem = MAX_BAUD_RATE % baudrate;
 157         /* Round to nearest divisor */
 158         if (((rem * 2) >= baudrate) && (baudrate != 110))
 159                 divisor++;
 160
 161         return divisor;
 162 }
 163
 164 static inline int qt2_set_port_config(struct usb_device *dev,
 165                                       unsigned char port_number,
 166                                       u16 baudrate, u16 lcr)
 167 {
 168         int divisor = calc_baud_divisor(baudrate);
 169         u16 index = ((u16) (lcr << 8) | (u16) (port_number));
 170
 171         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 172                                QT2_GET_SET_UART, 0x40,
 173                                divisor, index, NULL, 0, QT2_USB_TIMEOUT);
 174 }
 175
 176 static inline int qt2_control_msg(struct usb_device *dev,
 177                                   u8 request, u16 data, u16 index)
 178 {
 179         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 180                                request, 0x40, data, index,
 181                                NULL, 0, QT2_USB_TIMEOUT);
 182 }
 183
 184 static inline int qt2_setdevice(struct usb_device *dev, u8 *data)
 185 {
 186         u16 x = ((u16) (data[1] << 8) | (u16) (data[0]));
 187
 188         return qt2_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
 189 }
 190
 191
 192 static inline int qt2_getdevice(struct usb_device *dev, u8 *data)
 193 {
 194         return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 195                                QT_SET_GET_DEVICE, 0xc0, 0, 0,
 196                                data, 3, QT2_USB_TIMEOUT);
 197 }
 198
 199 static inline int qt2_getregister(struct usb_device *dev,
 200                                   u8 uart,
 201                                   u8 reg,
 202                                   u8 *data)
 203 {
 204         return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 205                                QT_SET_GET_REGISTER, 0xc0, reg,
 206                                uart, data, sizeof(*data), QT2_USB_TIMEOUT);
 207
 208 }
 209
 210 static inline int qt2_setregister(struct usb_device *dev,
 211                                   u8 uart, u8 reg, u16 data)
 212 {
 213         u16 value = (data << 8) | reg;
 214
 215         return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 216                                QT_SET_GET_REGISTER, 0x40, value, uart,
 217                                NULL, 0, QT2_USB_TIMEOUT);
 218 }
 219
 220 static inline int update_mctrl(struct qt2_port_private *port_priv,
 221                                unsigned int set, unsigned int clear)
 222 {
 223         struct usb_serial_port *port = port_priv->port;
 224         struct usb_device *dev = port->serial->dev;
 225         unsigned urb_value;
 226         int status;
 227
 228         if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
 229                 dev_dbg(&port->dev,
 230                         "update_mctrl - DTR|RTS not being set|cleared\n");
 231                 return 0;       /* no change */
 232         }
 233
 234         clear &= ~set;  /* 'set' takes precedence over 'clear' */
 235         urb_value = 0;
 236         if (set & TIOCM_DTR)
 237                 urb_value |= UART_MCR_DTR;
 238         if (set & TIOCM_RTS)
 239                 urb_value |= UART_MCR_RTS;
 240
 241         status = qt2_setregister(dev, port_priv->device_port, UART_MCR,
 242                                  urb_value);
 243         if (status < 0)
 244                 dev_err(&port->dev,
 245                         "update_mctrl - Error from MODEM_CTRL urb: %i\n",
 246                         status);
 247         return status;
 248 }
 249
 250 static int qt2_calc_num_ports(struct usb_serial *serial)
 251 {
 252         struct qt2_device_detail d;
 253         int i;
 254
 255         for (i = 0; d = qt2_device_details[i], d.product_id != 0; i++) {
 256                 if (d.product_id == le16_to_cpu(serial->dev->descriptor.idProduct))
 257                         return d.num_ports;
 258         }
 259
 260         /* we didn't recognize the device */
 261         dev_err(&serial->dev->dev,
 262                  "don't know the number of ports, assuming 1\n");
 263
 264         return 1;
 265 }
 266
 267 static void qt2_set_termios(struct tty_struct *tty,
 268                             struct usb_serial_port *port,
 269                             struct ktermios *old_termios)
 270 {
 271         struct usb_device *dev = port->serial->dev;
 272         struct qt2_port_private *port_priv;
 273         struct ktermios *termios = &tty->termios;
 274         u16 baud;
 275         unsigned int cflag = termios->c_cflag;
 276         u16 new_lcr = 0;
 277         int status;
 278
 279         port_priv = usb_get_serial_port_data(port);
 280
 281         if (cflag & PARENB) {
 282                 if (cflag & PARODD)
 283                         new_lcr |= UART_LCR_PARITY;
 284                 else
 285                         new_lcr |= SERIAL_EVEN_PARITY;
 286         }
 287
 288         switch (cflag & CSIZE) {
 289         case CS5:
 290                 new_lcr |= UART_LCR_WLEN5;
 291                 break;
 292         case CS6:
 293                 new_lcr |= UART_LCR_WLEN6;
 294                 break;
 295         case CS7:
 296                 new_lcr |= UART_LCR_WLEN7;
 297                 break;
 298         default:
 299         case CS8:
 300                 new_lcr |= UART_LCR_WLEN8;
 301                 break;
 302         }
 303
 304         baud = tty_get_baud_rate(tty);
 305         if (!baud)
 306                 baud = 9600;
 307
 308         status = qt2_set_port_config(dev, port_priv->device_port, baud,
 309                                      new_lcr);
 310         if (status < 0)
 311                 dev_err(&port->dev, "%s - qt2_set_port_config failed: %i\n",
 312                         __func__, status);
 313
 314         if (cflag & CRTSCTS)
 315                 status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
 316                                          SERIAL_CRTSCTS,
 317                                          port_priv->device_port);
 318         else
 319                 status = qt2_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
 320                                          0, port_priv->device_port);
 321         if (status < 0)
 322                 dev_err(&port->dev, "%s - set HW flow control failed: %i\n",
 323                         __func__, status);
 324
 325         if (I_IXOFF(tty) || I_IXON(tty)) {
 326                 u16 x = ((u16) (START_CHAR(tty) << 8) | (u16) (STOP_CHAR(tty)));
 327
 328                 status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
 329                                          x, port_priv->device_port);
 330         } else
 331                 status = qt2_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
 332                                          0, port_priv->device_port);
 333
 334         if (status < 0)
 335                 dev_err(&port->dev, "%s - set SW flow control failed: %i\n",
 336                         __func__, status);
 337
 338 }
 339
 340 static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port)
 341 {
 342         struct usb_serial *serial;
 343         struct qt2_port_private *port_priv;
 344         u8 *data;
 345         u16 device_port;
 346         int status;
 347         unsigned long flags;
 348
 349         device_port = (u16) (port->number - port->serial->minor);
 350
 351         serial = port->serial;
 352
 353         port_priv = usb_get_serial_port_data(port);
 354
 355         /* set the port to RS232 mode */
 356         status = qt2_control_msg(serial->dev, QT2_GET_SET_QMCR,
 357                                  QT2_QMCR_RS232, device_port);
 358         if (status < 0) {
 359                 dev_err(&port->dev,
 360                         "%s failed to set RS232 mode for port %i error %i\n",
 361                         __func__, device_port, status);
 362                 return status;
 363         }
 364
 365         data = kzalloc(2, GFP_KERNEL);
 366         if (!data)
 367                 return -ENOMEM;
 368
 369         /* open the port */
 370         status = usb_control_msg(serial->dev,
 371                                  usb_rcvctrlpipe(serial->dev, 0),
 372                                  QT_OPEN_CLOSE_CHANNEL,
 373                                  0xc0, 0,
 374                                  device_port, data, 2, QT2_USB_TIMEOUT);
 375
 376         if (status < 0) {
 377                 dev_err(&port->dev, "%s - open port failed %i", __func__,
 378                         status);
 379                 kfree(data);
 380                 return status;
 381         }
 382
 383         spin_lock_irqsave(&port_priv->lock, flags);
 384         port_priv->shadowLSR = data[0];
 385         port_priv->shadowMSR = data[1];
 386         spin_unlock_irqrestore(&port_priv->lock, flags);
 387
 388         kfree(data);
 389
 390         /* set to default speed and 8bit word size */
 391         status = qt2_set_port_config(serial->dev, device_port,
 392                                      DEFAULT_BAUD_RATE, UART_LCR_WLEN8);
 393         if (status < 0) {
 394                 dev_err(&port->dev,
 395                         "%s - initial setup failed for port %i (%i)\n",
 396                         __func__, port->number, device_port);
 397                 return status;
 398         }
 399
 400         port_priv->is_open = true;
 401         port_priv->device_port = (u8) device_port;
 402
 403         if (tty)
 404                 qt2_set_termios(tty, port, &tty->termios);
 405
 406         return 0;
 407
 408 }
 409
 410 static void qt2_close(struct usb_serial_port *port)
 411 {
 412         struct usb_serial *serial;
 413         struct qt2_port_private *port_priv;
 414         unsigned long flags;
 415         int i;
 416
 417         serial = port->serial;
 418         port_priv = usb_get_serial_port_data(port);
 419
 420         port_priv->is_open = false;
 421
 422         spin_lock_irqsave(&port_priv->urb_lock, flags);
 423         usb_kill_urb(port_priv->write_urb);
 424         port_priv->urb_in_use = false;
 425         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
 426
 427         mutex_lock(&port->serial->disc_mutex);
 428         if (port->serial->disconnected) {
 429                 mutex_unlock(&port->serial->disc_mutex);
 430                 return;
 431         }
 432
 433         /* flush the port transmit buffer */
 434         i = usb_control_msg(serial->dev,
 435                             usb_rcvctrlpipe(serial->dev, 0),
 436                             QT2_FLUSH_DEVICE, 0x40, 1,
 437                             port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
 438
 439         if (i < 0)
 440                 dev_err(&port->dev, "%s - transmit buffer flush failed: %i\n",
 441                         __func__, i);
 442
 443         /* flush the port receive buffer */
 444         i = usb_control_msg(serial->dev,
 445                             usb_rcvctrlpipe(serial->dev, 0),
 446                             QT2_FLUSH_DEVICE, 0x40, 0,
 447                             port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
 448
 449         if (i < 0)
 450                 dev_err(&port->dev, "%s - receive buffer flush failed: %i\n",
 451                         __func__, i);
 452
 453         /* close the port */
 454         i = usb_control_msg(serial->dev,
 455                             usb_sndctrlpipe(serial->dev, 0),
 456                             QT_OPEN_CLOSE_CHANNEL,
 457                             0x40, 0,
 458                             port_priv->device_port, NULL, 0, QT2_USB_TIMEOUT);
 459
 460         if (i < 0)
 461                 dev_err(&port->dev, "%s - close port failed %i\n",
 462                         __func__, i);
 463
 464         mutex_unlock(&port->serial->disc_mutex);
 465 }
 466
 467 static void qt2_disconnect(struct usb_serial *serial)
 468 {
 469         struct qt2_serial_private *serial_priv = usb_get_serial_data(serial);
 470
 471         usb_kill_urb(serial_priv->read_urb);
 472 }
 473
 474 static int get_serial_info(struct usb_serial_port *port,
 475                            struct serial_struct __user *retinfo)
 476 {
 477         struct serial_struct tmp;
 478
 479         if (!retinfo)
 480                 return -EFAULT;
 481
 482         memset(&tmp, 0, sizeof(tmp));
 483         tmp.line                = port->serial->minor;
 484         tmp.port                = 0;
 485         tmp.irq                 = 0;
 486         tmp.flags               = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
 487         tmp.xmit_fifo_size      = port->bulk_out_size;
 488         tmp.baud_base           = 9600;
 489         tmp.close_delay         = 5*HZ;
 490         tmp.closing_wait        = 30*HZ;
 491
 492         if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
 493                 return -EFAULT;
 494         return 0;
 495 }
 496
 497 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 498 {
 499         struct qt2_port_private *priv = usb_get_serial_port_data(port);
 500         struct async_icount prev, cur;
 501         unsigned long flags;
 502
 503         spin_lock_irqsave(&priv->lock, flags);
 504         prev = priv->icount;
 505         spin_unlock_irqrestore(&priv->lock, flags);
 506
 507         while (1) {
 508                 wait_event_interruptible(port->delta_msr_wait,
 509                                          (port->serial->disconnected ||
 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                 if (port->serial->disconnected)
 519                         return -EIO;
 520
 521                 spin_lock_irqsave(&priv->lock, flags);
 522                 cur = priv->icount;
 523                 spin_unlock_irqrestore(&priv->lock, flags);
 524
 525                 if ((prev.rng == cur.rng) &&
 526                     (prev.dsr == cur.dsr) &&
 527                     (prev.dcd == cur.dcd) &&
 528                     (prev.cts == cur.cts))
 529                         return -EIO;
 530
 531                 if ((arg & TIOCM_RNG && (prev.rng != cur.rng)) ||
 532                     (arg & TIOCM_DSR && (prev.dsr != cur.dsr)) ||
 533                     (arg & TIOCM_CD && (prev.dcd != cur.dcd)) ||
 534                     (arg & TIOCM_CTS && (prev.cts != cur.cts)))
 535                         return 0;
 536         }
 537         return 0;
 538 }
 539
 540 static int qt2_get_icount(struct tty_struct *tty,
 541                           struct serial_icounter_struct *icount)
 542 {
 543         struct usb_serial_port *port = tty->driver_data;
 544         struct qt2_port_private *priv = usb_get_serial_port_data(port);
 545         struct async_icount cnow = priv->icount;
 546
 547         icount->cts = cnow.cts;
 548         icount->dsr = cnow.dsr;
 549         icount->rng = cnow.rng;
 550         icount->dcd = cnow.dcd;
 551         icount->rx = cnow.rx;
 552         icount->tx = cnow.tx;
 553         icount->frame = cnow.frame;
 554         icount->overrun = cnow.overrun;
 555         icount->parity = cnow.parity;
 556         icount->brk = cnow.brk;
 557         icount->buf_overrun = cnow.buf_overrun;
 558
 559         return 0;
 560 }
 561
 562 static int qt2_ioctl(struct tty_struct *tty,
 563                      unsigned int cmd, unsigned long arg)
 564 {
 565         struct usb_serial_port *port = tty->driver_data;
 566
 567         switch (cmd) {
 568         case TIOCGSERIAL:
 569                 return get_serial_info(port,
 570                                        (struct serial_struct __user *)arg);
 571
 572         case TIOCMIWAIT:
 573                 return wait_modem_info(port, arg);
 574
 575         default:
 576                 break;
 577         }
 578
 579         return -ENOIOCTLCMD;
 580 }
 581
 582 static void qt2_process_status(struct usb_serial_port *port, unsigned char *ch)
 583 {
 584         switch (*ch) {
 585         case QT2_LINE_STATUS:
 586                 qt2_update_lsr(port, ch + 1);
 587                 break;
 588         case QT2_MODEM_STATUS:
 589                 qt2_update_msr(port, ch + 1);
 590                 break;
 591         }
 592 }
 593
 594 /* not needed, kept to document functionality */
 595 static void qt2_process_xmit_empty(struct usb_serial_port *port,
 596                                    unsigned char *ch)
 597 {
 598         int bytes_written;
 599
 600         bytes_written = (int)(*ch) + (int)(*(ch + 1) << 4);
 601 }
 602
 603 /* not needed, kept to document functionality */
 604 static void qt2_process_flush(struct usb_serial_port *port, unsigned char *ch)
 605 {
 606         return;
 607 }
 608
 609 void qt2_process_read_urb(struct urb *urb)
 610 {
 611         struct usb_serial *serial;
 612         struct qt2_serial_private *serial_priv;
 613         struct usb_serial_port *port;
 614         struct qt2_port_private *port_priv;
 615         bool escapeflag;
 616         unsigned char *ch;
 617         int i;
 618         unsigned char newport;
 619         int len = urb->actual_length;
 620
 621         if (!len)
 622                 return;
 623
 624         ch = urb->transfer_buffer;
 625         serial = urb->context;
 626         serial_priv = usb_get_serial_data(serial);
 627         port = serial->port[serial_priv->current_port];
 628         port_priv = usb_get_serial_port_data(port);
 629
 630         for (i = 0; i < urb->actual_length; i++) {
 631                 ch = (unsigned char *)urb->transfer_buffer + i;
 632                 if ((i <= (len - 3)) &&
 633                     (*ch == QT2_CONTROL_BYTE) &&
 634                     (*(ch + 1) == QT2_CONTROL_BYTE)) {
 635                         escapeflag = false;
 636                         switch (*(ch + 2)) {
 637                         case QT2_LINE_STATUS:
 638                         case QT2_MODEM_STATUS:
 639                                 if (i > (len - 4)) {
 640                                         dev_warn(&port->dev,
 641                                                  "%s - status message too short\n",
 642                                                 __func__);
 643                                         break;
 644                                 }
 645                                 qt2_process_status(port, ch + 2);
 646                                 i += 3;
 647                                 escapeflag = true;
 648                                 break;
 649                         case QT2_XMIT_HOLD:
 650                                 if (i > (len - 5)) {
 651                                         dev_warn(&port->dev,
 652                                                  "%s - xmit_empty message too short\n",
 653                                                  __func__);
 654                                         break;
 655                                 }
 656                                 qt2_process_xmit_empty(port, ch + 3);
 657                                 i += 4;
 658                                 escapeflag = true;
 659                                 break;
 660                         case QT2_CHANGE_PORT:
 661                                 if (i > (len - 4)) {
 662                                         dev_warn(&port->dev,
 663                                                  "%s - change_port message too short\n",
 664                                                  __func__);
 665                                         break;
 666                                 }
 667                                 tty_flip_buffer_push(&port->port);
 668
 669                                 newport = *(ch + 3);
 670
 671                                 if (newport > serial->num_ports) {
 672                                         dev_err(&port->dev,
 673                                                 "%s - port change to invalid port: %i\n",
 674                                                 __func__, newport);
 675                                         break;
 676                                 }
 677
 678                                 serial_priv->current_port = newport;
 679                                 port = serial->port[serial_priv->current_port];
 680                                 port_priv = usb_get_serial_port_data(port);
 681                                 i += 3;
 682                                 escapeflag = true;
 683                                 break;
 684                         case QT2_REC_FLUSH:
 685                         case QT2_XMIT_FLUSH:
 686                                 qt2_process_flush(port, ch + 2);
 687                                 i += 2;
 688                                 escapeflag = true;
 689                                 break;
 690                         case QT2_CONTROL_ESCAPE:
 691                                 tty_buffer_request_room(&port->port, 2);
 692                                 tty_insert_flip_string(&port->port, ch, 2);
 693                                 i += 2;
 694                                 escapeflag = true;
 695                                 break;
 696                         default:
 697                                 dev_warn(&port->dev,
 698                                          "%s - unsupported command %i\n",
 699                                          __func__, *(ch + 2));
 700                                 break;
 701                         }
 702                         if (escapeflag)
 703                                 continue;
 704                 }
 705
 706                 tty_buffer_request_room(&port->port, 1);
 707                 tty_insert_flip_string(&port->port, ch, 1);
 708         }
 709
 710         tty_flip_buffer_push(&port->port);
 711 }
 712
 713 static void qt2_write_bulk_callback(struct urb *urb)
 714 {
 715         struct usb_serial_port *port;
 716         struct qt2_port_private *port_priv;
 717
 718         port = urb->context;
 719         port_priv = usb_get_serial_port_data(port);
 720
 721         spin_lock(&port_priv->urb_lock);
 722
 723         port_priv->urb_in_use = false;
 724         usb_serial_port_softint(port);
 725
 726         spin_unlock(&port_priv->urb_lock);
 727
 728 }
 729
 730 static void qt2_read_bulk_callback(struct urb *urb)
 731 {
 732         struct usb_serial *serial = urb->context;
 733         int status;
 734
 735         if (urb->status) {
 736                 dev_warn(&serial->dev->dev,
 737                          "%s - non-zero urb status: %i\n", __func__,
 738                          urb->status);
 739                 return;
 740         }
 741
 742         qt2_process_read_urb(urb);
 743
 744         status = usb_submit_urb(urb, GFP_ATOMIC);
 745         if (status != 0)
 746                 dev_err(&serial->dev->dev,
 747                         "%s - resubmit read urb failed: %i\n",
 748                         __func__, status);
 749 }
 750
 751 static int qt2_setup_urbs(struct usb_serial *serial)
 752 {
 753         struct usb_serial_port *port0;
 754         struct qt2_serial_private *serial_priv;
 755         int status;
 756
 757         port0 = serial->port[0];
 758
 759         serial_priv = usb_get_serial_data(serial);
 760         serial_priv->read_urb = usb_alloc_urb(0, GFP_KERNEL);
 761         if (!serial_priv->read_urb) {
 762                 dev_err(&serial->dev->dev, "No free urbs available\n");
 763                 return -ENOMEM;
 764         }
 765
 766         usb_fill_bulk_urb(serial_priv->read_urb, serial->dev,
 767                           usb_rcvbulkpipe(serial->dev,
 768                                           port0->bulk_in_endpointAddress),
 769                           serial_priv->read_buffer,
 770                           sizeof(serial_priv->read_buffer),
 771                           qt2_read_bulk_callback, serial);
 772
 773         status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL);
 774         if (status != 0) {
 775                 dev_err(&serial->dev->dev,
 776                         "%s - submit read urb failed %i\n", __func__, status);
 777                 usb_free_urb(serial_priv->read_urb);
 778                 return status;
 779         }
 780
 781         return 0;
 782 }
 783
 784 static int qt2_attach(struct usb_serial *serial)
 785 {
 786         struct qt2_serial_private *serial_priv;
 787         int status;
 788
 789         /* power on unit */
 790         status = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 791                                  0xc2, 0x40, 0x8000, 0, NULL, 0,
 792                                  QT2_USB_TIMEOUT);
 793         if (status < 0) {
 794                 dev_err(&serial->dev->dev,
 795                         "%s - failed to power on unit: %i\n", __func__, status);
 796                 return status;
 797         }
 798
 799         serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
 800         if (!serial_priv) {
 801                 dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
 802                 return -ENOMEM;
 803         }
 804
 805         usb_set_serial_data(serial, serial_priv);
 806
 807         status = qt2_setup_urbs(serial);
 808         if (status != 0)
 809                 goto attach_failed;
 810
 811         return 0;
 812
 813 attach_failed:
 814         kfree(serial_priv);
 815         return status;
 816 }
 817
 818 static int qt2_port_probe(struct usb_serial_port *port)
 819 {
 820         struct usb_serial *serial = port->serial;
 821         struct qt2_port_private *port_priv;
 822         u8 bEndpointAddress;
 823
 824         port_priv = kzalloc(sizeof(*port_priv), GFP_KERNEL);
 825         if (!port_priv)
 826                 return -ENOMEM;
 827
 828         spin_lock_init(&port_priv->lock);
 829         spin_lock_init(&port_priv->urb_lock);
 830         port_priv->port = port;
 831
 832         port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL);
 833         if (!port_priv->write_urb) {
 834                 kfree(port_priv);
 835                 return -ENOMEM;
 836         }
 837         bEndpointAddress = serial->port[0]->bulk_out_endpointAddress;
 838         usb_fill_bulk_urb(port_priv->write_urb, serial->dev,
 839                                 usb_sndbulkpipe(serial->dev, bEndpointAddress),
 840                                 port_priv->write_buffer,
 841                                 sizeof(port_priv->write_buffer),
 842                                 qt2_write_bulk_callback, port);
 843
 844         usb_set_serial_port_data(port, port_priv);
 845
 846         return 0;
 847 }
 848
 849 static int qt2_port_remove(struct usb_serial_port *port)
 850 {
 851         struct qt2_port_private *port_priv;
 852
 853         port_priv = usb_get_serial_port_data(port);
 854         usb_free_urb(port_priv->write_urb);
 855         kfree(port_priv);
 856
 857         return 0;
 858 }
 859
 860 static int qt2_tiocmget(struct tty_struct *tty)
 861 {
 862         struct usb_serial_port *port = tty->driver_data;
 863         struct usb_device *dev = port->serial->dev;
 864         struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
 865         u8 *d;
 866         int r;
 867
 868         d = kzalloc(2, GFP_KERNEL);
 869         if (!d)
 870                 return -ENOMEM;
 871
 872         r = qt2_getregister(dev, port_priv->device_port, UART_MCR, d);
 873         if (r < 0)
 874                 goto mget_out;
 875
 876         r = qt2_getregister(dev, port_priv->device_port, UART_MSR, d + 1);
 877         if (r < 0)
 878                 goto mget_out;
 879
 880         r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
 881             (d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
 882             (d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
 883             (d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
 884             (d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
 885             (d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);
 886
 887 mget_out:
 888         kfree(d);
 889         return r;
 890 }
 891
 892 static int qt2_tiocmset(struct tty_struct *tty,
 893                         unsigned int set, unsigned int clear)
 894 {
 895         struct qt2_port_private *port_priv;
 896
 897         port_priv = usb_get_serial_port_data(tty->driver_data);
 898         return update_mctrl(port_priv, set, clear);
 899 }
 900
 901 static void qt2_break_ctl(struct tty_struct *tty, int break_state)
 902 {
 903         struct usb_serial_port *port = tty->driver_data;
 904         struct qt2_port_private *port_priv;
 905         int status;
 906         u16 val;
 907
 908         port_priv = usb_get_serial_port_data(port);
 909
 910         if (!port_priv->is_open) {
 911                 dev_err(&port->dev,
 912                         "%s - port is not open\n", __func__);
 913                 return;
 914         }
 915
 916         val = (break_state == -1) ? 1 : 0;
 917
 918         status = qt2_control_msg(port->serial->dev, QT2_BREAK_CONTROL,
 919                                  val, port_priv->device_port);
 920         if (status < 0)
 921                 dev_warn(&port->dev,
 922                          "%s - failed to send control message: %i\n", __func__,
 923                          status);
 924 }
 925
 926
 927
 928 static void qt2_dtr_rts(struct usb_serial_port *port, int on)
 929 {
 930         struct usb_device *dev = port->serial->dev;
 931         struct qt2_port_private *port_priv = usb_get_serial_port_data(port);
 932
 933         /* Disable flow control */
 934         if (!on) {
 935                 if (qt2_setregister(dev, port_priv->device_port,
 936                                            UART_MCR, 0) < 0)
 937                         dev_warn(&port->dev, "error from flowcontrol urb\n");
 938         }
 939         /* drop RTS and DTR */
 940         if (on)
 941                 update_mctrl(port_priv, TIOCM_DTR | TIOCM_RTS, 0);
 942         else
 943                 update_mctrl(port_priv, 0, TIOCM_DTR | TIOCM_RTS);
 944 }
 945
 946 static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch)
 947 {
 948         struct qt2_port_private *port_priv;
 949         u8 newMSR = (u8) *ch;
 950         unsigned long flags;
 951
 952         port_priv = usb_get_serial_port_data(port);
 953
 954         spin_lock_irqsave(&port_priv->lock, flags);
 955         port_priv->shadowMSR = newMSR;
 956         spin_unlock_irqrestore(&port_priv->lock, flags);
 957
 958         if (newMSR & UART_MSR_ANY_DELTA) {
 959                 /* update input line counters */
 960                 if (newMSR & UART_MSR_DCTS)
 961                         port_priv->icount.cts++;
 962
 963                 if (newMSR & UART_MSR_DDSR)
 964                         port_priv->icount.dsr++;
 965
 966                 if (newMSR & UART_MSR_DDCD)
 967                         port_priv->icount.dcd++;
 968
 969                 if (newMSR & UART_MSR_TERI)
 970                         port_priv->icount.rng++;
 971
 972                 wake_up_interruptible(&port->delta_msr_wait);
 973         }
 974 }
 975
 976 static void qt2_update_lsr(struct usb_serial_port *port, unsigned char *ch)
 977 {
 978         struct qt2_port_private *port_priv;
 979         struct async_icount *icount;
 980         unsigned long flags;
 981         u8 newLSR = (u8) *ch;
 982
 983         port_priv = usb_get_serial_port_data(port);
 984
 985         if (newLSR & UART_LSR_BI)
 986                 newLSR &= (u8) (UART_LSR_OE | UART_LSR_BI);
 987
 988         spin_lock_irqsave(&port_priv->lock, flags);
 989         port_priv->shadowLSR = newLSR;
 990         spin_unlock_irqrestore(&port_priv->lock, flags);
 991
 992         icount = &port_priv->icount;
 993
 994         if (newLSR & UART_LSR_BRK_ERROR_BITS) {
 995
 996                 if (newLSR & UART_LSR_BI)
 997                         icount->brk++;
 998
 999                 if (newLSR & UART_LSR_OE)
1000                         icount->overrun++;
1001
1002                 if (newLSR & UART_LSR_PE)
1003                         icount->parity++;
1004
1005                 if (newLSR & UART_LSR_FE)
1006                         icount->frame++;
1007         }
1008
1009 }
1010
1011 static int qt2_write_room(struct tty_struct *tty)
1012 {
1013         struct usb_serial_port *port = tty->driver_data;
1014         struct qt2_port_private *port_priv;
1015         unsigned long flags = 0;
1016         int r;
1017
1018         port_priv = usb_get_serial_port_data(port);
1019
1020         spin_lock_irqsave(&port_priv->urb_lock, flags);
1021
1022         if (port_priv->urb_in_use)
1023                 r = 0;
1024         else
1025                 r = QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE;
1026
1027         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1028
1029         return r;
1030 }
1031
1032 static int qt2_write(struct tty_struct *tty,
1033                      struct usb_serial_port *port,
1034                      const unsigned char *buf, int count)
1035 {
1036         struct qt2_port_private *port_priv;
1037         struct urb *write_urb;
1038         unsigned char *data;
1039         unsigned long flags;
1040         int status;
1041         int bytes_out = 0;
1042
1043         port_priv = usb_get_serial_port_data(port);
1044
1045         if (port_priv->write_urb == NULL) {
1046                 dev_err(&port->dev, "%s - no output urb\n", __func__);
1047                 return 0;
1048         }
1049         write_urb = port_priv->write_urb;
1050
1051         count = min(count, QT2_WRITE_BUFFER_SIZE - QT2_WRITE_CONTROL_SIZE);
1052
1053         data = write_urb->transfer_buffer;
1054         spin_lock_irqsave(&port_priv->urb_lock, flags);
1055         if (port_priv->urb_in_use == true) {
1056                 dev_err(&port->dev, "qt2_write - urb is in use\n");
1057                 goto write_out;
1058         }
1059
1060         *data++ = QT2_CONTROL_BYTE;
1061         *data++ = QT2_CONTROL_BYTE;
1062         *data++ = port_priv->device_port;
1063         put_unaligned_le16(count, data);
1064         data += 2;
1065         memcpy(data, buf, count);
1066
1067         write_urb->transfer_buffer_length = count + QT2_WRITE_CONTROL_SIZE;
1068
1069         status = usb_submit_urb(write_urb, GFP_ATOMIC);
1070         if (status == 0) {
1071                 port_priv->urb_in_use = true;
1072                 bytes_out += count;
1073         }
1074
1075 write_out:
1076         spin_unlock_irqrestore(&port_priv->urb_lock, flags);
1077         return bytes_out;
1078 }
1079
1080
1081 static struct usb_serial_driver qt2_device = {
1082         .driver = {
1083                 .owner = THIS_MODULE,
1084                 .name = "quatech-serial",
1085         },
1086         .description         = DRIVER_DESC,
1087         .id_table            = id_table,
1088         .open                = qt2_open,
1089         .close               = qt2_close,
1090         .write               = qt2_write,
1091         .write_room          = qt2_write_room,
1092         .calc_num_ports      = qt2_calc_num_ports,
1093         .attach              = qt2_attach,
1094         .release             = qt2_release,
1095         .disconnect          = qt2_disconnect,
1096         .port_probe          = qt2_port_probe,
1097         .port_remove         = qt2_port_remove,
1098         .dtr_rts             = qt2_dtr_rts,
1099         .break_ctl           = qt2_break_ctl,
1100         .tiocmget            = qt2_tiocmget,
1101         .tiocmset            = qt2_tiocmset,
1102         .get_icount          = qt2_get_icount,
1103         .ioctl               = qt2_ioctl,
1104         .set_termios         = qt2_set_termios,
1105 };
1106
1107 static struct usb_serial_driver *const serial_drivers[] = {
1108         &qt2_device, NULL
1109 };
1110
1111 module_usb_serial_driver(serial_drivers, id_table);
1112
1113 MODULE_DESCRIPTION(DRIVER_DESC);
1114 MODULE_LICENSE("GPL");