drivers/usb/serial/ch341.c

   1 /*
   2  * Copyright 2007, Frank A Kingswood <frank@kingswood-consulting.co.uk>
   3  * Copyright 2007, Werner Cornelius <werner@cornelius-consult.de>
   4  * Copyright 2009, Boris Hajduk <boris@hajduk.org>
   5  *
   6  * ch341.c implements a serial port driver for the Winchiphead CH341.
   7  *
   8  * The CH341 device can be used to implement an RS232 asynchronous
   9  * serial port, an IEEE-1284 parallel printer port or a memory-like
  10  * interface. In all cases the CH341 supports an I2C interface as well.
  11  * This driver only supports the asynchronous serial interface.
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License version
  15  * 2 as published by the Free Software Foundation.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/init.h>
  20 #include <linux/tty.h>
  21 #include <linux/module.h>
  22 #include <linux/usb.h>
  23 #include <linux/usb/serial.h>
  24 #include <linux/serial.h>
  25
  26 #define DEFAULT_BAUD_RATE 9600
  27 #define DEFAULT_TIMEOUT   1000
  28
  29 /* flags for IO-Bits */
  30 #define CH341_BIT_RTS (1 << 6)
  31 #define CH341_BIT_DTR (1 << 5)
  32
  33 /******************************/
  34 /* interrupt pipe definitions */
  35 /******************************/
  36 /* always 4 interrupt bytes */
  37 /* first irq byte normally 0x08 */
  38 /* second irq byte base 0x7d + below */
  39 /* third irq byte base 0x94 + below */
  40 /* fourth irq byte normally 0xee */
  41
  42 /* second interrupt byte */
  43 #define CH341_MULT_STAT 0x04 /* multiple status since last interrupt event */
  44
  45 /* status returned in third interrupt answer byte, inverted in data
  46    from irq */
  47 #define CH341_BIT_CTS 0x01
  48 #define CH341_BIT_DSR 0x02
  49 #define CH341_BIT_RI  0x04
  50 #define CH341_BIT_DCD 0x08
  51 #define CH341_BITS_MODEM_STAT 0x0f /* all bits */
  52
  53 /*******************************/
  54 /* baudrate calculation factor */
  55 /*******************************/
  56 #define CH341_BAUDBASE_FACTOR 1532620800
  57 #define CH341_BAUDBASE_DIVMAX 3
  58
  59 /* Break support - the information used to implement this was gleaned from
  60  * the Net/FreeBSD uchcom.c driver by Takanori Watanabe.  Domo arigato.
  61  */
  62
  63 #define CH341_REQ_WRITE_REG    0x9A
  64 #define CH341_REQ_READ_REG     0x95
  65 #define CH341_REG_BREAK1       0x05
  66 #define CH341_REG_BREAK2       0x18
  67 #define CH341_NBREAK_BITS_REG1 0x01
  68 #define CH341_NBREAK_BITS_REG2 0x40
  69
  70
  71 static int debug;
  72
  73 static struct usb_device_id id_table [] = {
  74         { USB_DEVICE(0x4348, 0x5523) },
  75         { USB_DEVICE(0x1a86, 0x7523) },
  76         { USB_DEVICE(0x1a86, 0x5523) },
  77         { },
  78 };
  79 MODULE_DEVICE_TABLE(usb, id_table);
  80
  81 struct ch341_private {
  82         spinlock_t lock; /* access lock */
  83         wait_queue_head_t delta_msr_wait; /* wait queue for modem status */
  84         unsigned baud_rate; /* set baud rate */
  85         u8 line_control; /* set line control value RTS/DTR */
  86         u8 line_status; /* active status of modem control inputs */
  87         u8 multi_status_change; /* status changed multiple since last call */
  88 };
  89
  90 static int ch341_control_out(struct usb_device *dev, u8 request,
  91                              u16 value, u16 index)
  92 {
  93         int r;
  94         dbg("ch341_control_out(%02x,%02x,%04x,%04x)", USB_DIR_OUT|0x40,
  95                 (int)request, (int)value, (int)index);
  96
  97         r = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request,
  98                             USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
  99                             value, index, NULL, 0, DEFAULT_TIMEOUT);
 100
 101         return r;
 102 }
 103
 104 static int ch341_control_in(struct usb_device *dev,
 105                             u8 request, u16 value, u16 index,
 106                             char *buf, unsigned bufsize)
 107 {
 108         int r;
 109         dbg("ch341_control_in(%02x,%02x,%04x,%04x,%p,%u)", USB_DIR_IN|0x40,
 110                 (int)request, (int)value, (int)index, buf, (int)bufsize);
 111
 112         r = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), request,
 113                             USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 114                             value, index, buf, bufsize, DEFAULT_TIMEOUT);
 115         return r;
 116 }
 117
 118 static int ch341_set_baudrate(struct usb_device *dev,
 119                               struct ch341_private *priv)
 120 {
 121         short a, b;
 122         int r;
 123         unsigned long factor;
 124         short divisor;
 125
 126         dbg("ch341_set_baudrate(%d)", priv->baud_rate);
 127
 128         if (!priv->baud_rate)
 129                 return -EINVAL;
 130         factor = (CH341_BAUDBASE_FACTOR / priv->baud_rate);
 131         divisor = CH341_BAUDBASE_DIVMAX;
 132
 133         while ((factor > 0xfff0) && divisor) {
 134                 factor >>= 3;
 135                 divisor--;
 136         }
 137
 138         if (factor > 0xfff0)
 139                 return -EINVAL;
 140
 141         factor = 0x10000 - factor;
 142         a = (factor & 0xff00) | divisor;
 143         b = factor & 0xff;
 144
 145         r = ch341_control_out(dev, 0x9a, 0x1312, a);
 146         if (!r)
 147                 r = ch341_control_out(dev, 0x9a, 0x0f2c, b);
 148
 149         return r;
 150 }
 151
 152 static int ch341_set_handshake(struct usb_device *dev, u8 control)
 153 {
 154         dbg("ch341_set_handshake(0x%02x)", control);
 155         return ch341_control_out(dev, 0xa4, ~control, 0);
 156 }
 157
 158 static int ch341_get_status(struct usb_device *dev, struct ch341_private *priv)
 159 {
 160         char *buffer;
 161         int r;
 162         const unsigned size = 8;
 163         unsigned long flags;
 164
 165         dbg("ch341_get_status()");
 166
 167         buffer = kmalloc(size, GFP_KERNEL);
 168         if (!buffer)
 169                 return -ENOMEM;
 170
 171         r = ch341_control_in(dev, 0x95, 0x0706, 0, buffer, size);
 172         if (r < 0)
 173                 goto out;
 174
 175         /* setup the private status if available */
 176         if (r == 2) {
 177                 r = 0;
 178                 spin_lock_irqsave(&priv->lock, flags);
 179                 priv->line_status = (~(*buffer)) & CH341_BITS_MODEM_STAT;
 180                 priv->multi_status_change = 0;
 181                 spin_unlock_irqrestore(&priv->lock, flags);
 182         } else
 183                 r = -EPROTO;
 184
 185 out:    kfree(buffer);
 186         return r;
 187 }
 188
 189 /* -------------------------------------------------------------------------- */
 190
 191 static int ch341_configure(struct usb_device *dev, struct ch341_private *priv)
 192 {
 193         char *buffer;
 194         int r;
 195         const unsigned size = 8;
 196
 197         dbg("ch341_configure()");
 198
 199         buffer = kmalloc(size, GFP_KERNEL);
 200         if (!buffer)
 201                 return -ENOMEM;
 202
 203         /* expect two bytes 0x27 0x00 */
 204         r = ch341_control_in(dev, 0x5f, 0, 0, buffer, size);
 205         if (r < 0)
 206                 goto out;
 207
 208         r = ch341_control_out(dev, 0xa1, 0, 0);
 209         if (r < 0)
 210                 goto out;
 211
 212         r = ch341_set_baudrate(dev, priv);
 213         if (r < 0)
 214                 goto out;
 215
 216         /* expect two bytes 0x56 0x00 */
 217         r = ch341_control_in(dev, 0x95, 0x2518, 0, buffer, size);
 218         if (r < 0)
 219                 goto out;
 220
 221         r = ch341_control_out(dev, 0x9a, 0x2518, 0x0050);
 222         if (r < 0)
 223                 goto out;
 224
 225         /* expect 0xff 0xee */
 226         r = ch341_get_status(dev, priv);
 227         if (r < 0)
 228                 goto out;
 229
 230         r = ch341_control_out(dev, 0xa1, 0x501f, 0xd90a);
 231         if (r < 0)
 232                 goto out;
 233
 234         r = ch341_set_baudrate(dev, priv);
 235         if (r < 0)
 236                 goto out;
 237
 238         r = ch341_set_handshake(dev, priv->line_control);
 239         if (r < 0)
 240                 goto out;
 241
 242         /* expect 0x9f 0xee */
 243         r = ch341_get_status(dev, priv);
 244
 245 out:    kfree(buffer);
 246         return r;
 247 }
 248
 249 /* allocate private data */
 250 static int ch341_attach(struct usb_serial *serial)
 251 {
 252         struct ch341_private *priv;
 253         int r;
 254
 255         dbg("ch341_attach()");
 256
 257         /* private data */
 258         priv = kzalloc(sizeof(struct ch341_private), GFP_KERNEL);
 259         if (!priv)
 260                 return -ENOMEM;
 261
 262         spin_lock_init(&priv->lock);
 263         init_waitqueue_head(&priv->delta_msr_wait);
 264         priv->baud_rate = DEFAULT_BAUD_RATE;
 265         priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR;
 266
 267         r = ch341_configure(serial->dev, priv);
 268         if (r < 0)
 269                 goto error;
 270
 271         usb_set_serial_port_data(serial->port[0], priv);
 272         return 0;
 273
 274 error:  kfree(priv);
 275         return r;
 276 }
 277
 278 static int ch341_carrier_raised(struct usb_serial_port *port)
 279 {
 280         struct ch341_private *priv = usb_get_serial_port_data(port);
 281         if (priv->line_status & CH341_BIT_DCD)
 282                 return 1;
 283         return 0;
 284 }
 285
 286 static void ch341_dtr_rts(struct usb_serial_port *port, int on)
 287 {
 288         struct ch341_private *priv = usb_get_serial_port_data(port);
 289         unsigned long flags;
 290
 291         dbg("%s - port %d", __func__, port->number);
 292         /* drop DTR and RTS */
 293         spin_lock_irqsave(&priv->lock, flags);
 294         if (on)
 295                 priv->line_control |= CH341_BIT_RTS | CH341_BIT_DTR;
 296         else
 297                 priv->line_control &= ~(CH341_BIT_RTS | CH341_BIT_DTR);
 298         spin_unlock_irqrestore(&priv->lock, flags);
 299         ch341_set_handshake(port->serial->dev, priv->line_control);
 300         wake_up_interruptible(&priv->delta_msr_wait);
 301 }
 302
 303 static void ch341_close(struct usb_serial_port *port)
 304 {
 305         dbg("%s - port %d", __func__, port->number);
 306
 307         /* shutdown our urbs */
 308         dbg("%s - shutting down urbs", __func__);
 309         usb_kill_urb(port->write_urb);
 310         usb_kill_urb(port->read_urb);
 311         usb_kill_urb(port->interrupt_in_urb);
 312 }
 313
 314
 315 /* open this device, set default parameters */
 316 static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port)
 317 {
 318         struct usb_serial *serial = port->serial;
 319         struct ch341_private *priv = usb_get_serial_port_data(serial->port[0]);
 320         int r;
 321
 322         dbg("ch341_open()");
 323
 324         priv->baud_rate = DEFAULT_BAUD_RATE;
 325
 326         r = ch341_configure(serial->dev, priv);
 327         if (r)
 328                 goto out;
 329
 330         r = ch341_set_handshake(serial->dev, priv->line_control);
 331         if (r)
 332                 goto out;
 333
 334         r = ch341_set_baudrate(serial->dev, priv);
 335         if (r)
 336                 goto out;
 337
 338         dbg("%s - submitting interrupt urb", __func__);
 339         port->interrupt_in_urb->dev = serial->dev;
 340         r = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 341         if (r) {
 342                 dev_err(&port->dev, "%s - failed submitting interrupt urb,"
 343                         " error %d\n", __func__, r);
 344                 ch341_close(port);
 345                 return -EPROTO;
 346         }
 347
 348         r = usb_serial_generic_open(tty, port);
 349
 350 out:    return r;
 351 }
 352
 353 /* Old_termios contains the original termios settings and
 354  * tty->termios contains the new setting to be used.
 355  */
 356 static void ch341_set_termios(struct tty_struct *tty,
 357                 struct usb_serial_port *port, struct ktermios *old_termios)
 358 {
 359         struct ch341_private *priv = usb_get_serial_port_data(port);
 360         unsigned baud_rate;
 361         unsigned long flags;
 362
 363         dbg("ch341_set_termios()");
 364
 365         baud_rate = tty_get_baud_rate(tty);
 366
 367         priv->baud_rate = baud_rate;
 368
 369         if (baud_rate) {
 370                 spin_lock_irqsave(&priv->lock, flags);
 371                 priv->line_control |= (CH341_BIT_DTR | CH341_BIT_RTS);
 372                 spin_unlock_irqrestore(&priv->lock, flags);
 373                 ch341_set_baudrate(port->serial->dev, priv);
 374         } else {
 375                 spin_lock_irqsave(&priv->lock, flags);
 376                 priv->line_control &= ~(CH341_BIT_DTR | CH341_BIT_RTS);
 377                 spin_unlock_irqrestore(&priv->lock, flags);
 378         }
 379
 380         ch341_set_handshake(port->serial->dev, priv->line_control);
 381
 382         /* Unimplemented:
 383          * (cflag & CSIZE) : data bits [5, 8]
 384          * (cflag & PARENB) : parity {NONE, EVEN, ODD}
 385          * (cflag & CSTOPB) : stop bits [1, 2]
 386          */
 387 }
 388
 389 static void ch341_break_ctl(struct tty_struct *tty, int break_state)
 390 {
 391         const uint16_t ch341_break_reg =
 392                 CH341_REG_BREAK1 | ((uint16_t) CH341_REG_BREAK2 << 8);
 393         struct usb_serial_port *port = tty->driver_data;
 394         int r;
 395         uint16_t reg_contents;
 396         uint8_t break_reg[2];
 397
 398         dbg("%s()", __func__);
 399
 400         r = ch341_control_in(port->serial->dev, CH341_REQ_READ_REG,
 401                         ch341_break_reg, 0, break_reg, sizeof(break_reg));
 402         if (r < 0) {
 403                 printk(KERN_WARNING "%s: USB control read error whilst getting"
 404                                 " break register contents.\n", __FILE__);
 405                 return;
 406         }
 407         dbg("%s - initial ch341 break register contents - reg1: %x, reg2: %x",
 408                         __func__, break_reg[0], break_reg[1]);
 409         if (break_state != 0) {
 410                 dbg("%s - Enter break state requested", __func__);
 411                 break_reg[0] &= ~CH341_NBREAK_BITS_REG1;
 412                 break_reg[1] &= ~CH341_NBREAK_BITS_REG2;
 413         } else {
 414                 dbg("%s - Leave break state requested", __func__);
 415                 break_reg[0] |= CH341_NBREAK_BITS_REG1;
 416                 break_reg[1] |= CH341_NBREAK_BITS_REG2;
 417         }
 418         dbg("%s - New ch341 break register contents - reg1: %x, reg2: %x",
 419                         __func__, break_reg[0], break_reg[1]);
 420         reg_contents = (uint16_t)break_reg[0] | ((uint16_t)break_reg[1] << 8);
 421         r = ch341_control_out(port->serial->dev, CH341_REQ_WRITE_REG,
 422                         ch341_break_reg, reg_contents);
 423         if (r < 0)
 424                 printk(KERN_WARNING "%s: USB control write error whilst setting"
 425                                 " break register contents.\n", __FILE__);
 426 }
 427
 428 static int ch341_tiocmset(struct tty_struct *tty, struct file *file,
 429                           unsigned int set, unsigned int clear)
 430 {
 431         struct usb_serial_port *port = tty->driver_data;
 432         struct ch341_private *priv = usb_get_serial_port_data(port);
 433         unsigned long flags;
 434         u8 control;
 435
 436         spin_lock_irqsave(&priv->lock, flags);
 437         if (set & TIOCM_RTS)
 438                 priv->line_control |= CH341_BIT_RTS;
 439         if (set & TIOCM_DTR)
 440                 priv->line_control |= CH341_BIT_DTR;
 441         if (clear & TIOCM_RTS)
 442                 priv->line_control &= ~CH341_BIT_RTS;
 443         if (clear & TIOCM_DTR)
 444                 priv->line_control &= ~CH341_BIT_DTR;
 445         control = priv->line_control;
 446         spin_unlock_irqrestore(&priv->lock, flags);
 447
 448         return ch341_set_handshake(port->serial->dev, control);
 449 }
 450
 451 static void ch341_read_int_callback(struct urb *urb)
 452 {
 453         struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
 454         unsigned char *data = urb->transfer_buffer;
 455         unsigned int actual_length = urb->actual_length;
 456         int status;
 457
 458         dbg("%s (%d)", __func__, port->number);
 459
 460         switch (urb->status) {
 461         case 0:
 462                 /* success */
 463                 break;
 464         case -ECONNRESET:
 465         case -ENOENT:
 466         case -ESHUTDOWN:
 467                 /* this urb is terminated, clean up */
 468                 dbg("%s - urb shutting down with status: %d", __func__,
 469                     urb->status);
 470                 return;
 471         default:
 472                 dbg("%s - nonzero urb status received: %d", __func__,
 473                     urb->status);
 474                 goto exit;
 475         }
 476
 477         usb_serial_debug_data(debug, &port->dev, __func__,
 478                               urb->actual_length, urb->transfer_buffer);
 479
 480         if (actual_length >= 4) {
 481                 struct ch341_private *priv = usb_get_serial_port_data(port);
 482                 unsigned long flags;
 483                 u8 prev_line_status = priv->line_status;
 484
 485                 spin_lock_irqsave(&priv->lock, flags);
 486                 priv->line_status = (~(data[2])) & CH341_BITS_MODEM_STAT;
 487                 if ((data[1] & CH341_MULT_STAT))
 488                         priv->multi_status_change = 1;
 489                 spin_unlock_irqrestore(&priv->lock, flags);
 490
 491                 if ((priv->line_status ^ prev_line_status) & CH341_BIT_DCD) {
 492                         struct tty_struct *tty = tty_port_tty_get(&port->port);
 493                         if (tty)
 494                                 usb_serial_handle_dcd_change(port, tty,
 495                                             priv->line_status & CH341_BIT_DCD);
 496                         tty_kref_put(tty);
 497                 }
 498
 499                 wake_up_interruptible(&priv->delta_msr_wait);
 500         }
 501
 502 exit:
 503         status = usb_submit_urb(urb, GFP_ATOMIC);
 504         if (status)
 505                 dev_err(&urb->dev->dev,
 506                         "%s - usb_submit_urb failed with result %d\n",
 507                         __func__, status);
 508 }
 509
 510 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 511 {
 512         struct ch341_private *priv = usb_get_serial_port_data(port);
 513         unsigned long flags;
 514         u8 prevstatus;
 515         u8 status;
 516         u8 changed;
 517         u8 multi_change = 0;
 518
 519         spin_lock_irqsave(&priv->lock, flags);
 520         prevstatus = priv->line_status;
 521         priv->multi_status_change = 0;
 522         spin_unlock_irqrestore(&priv->lock, flags);
 523
 524         while (!multi_change) {
 525                 interruptible_sleep_on(&priv->delta_msr_wait);
 526                 /* see if a signal did it */
 527                 if (signal_pending(current))
 528                         return -ERESTARTSYS;
 529
 530                 spin_lock_irqsave(&priv->lock, flags);
 531                 status = priv->line_status;
 532                 multi_change = priv->multi_status_change;
 533                 spin_unlock_irqrestore(&priv->lock, flags);
 534
 535                 changed = prevstatus ^ status;
 536
 537                 if (((arg & TIOCM_RNG) && (changed & CH341_BIT_RI)) ||
 538                     ((arg & TIOCM_DSR) && (changed & CH341_BIT_DSR)) ||
 539                     ((arg & TIOCM_CD)  && (changed & CH341_BIT_DCD)) ||
 540                     ((arg & TIOCM_CTS) && (changed & CH341_BIT_CTS))) {
 541                         return 0;
 542                 }
 543                 prevstatus = status;
 544         }
 545
 546         return 0;
 547 }
 548
 549 /*static int ch341_ioctl(struct usb_serial_port *port, struct file *file,*/
 550 static int ch341_ioctl(struct tty_struct *tty, struct file *file,
 551                         unsigned int cmd, unsigned long arg)
 552 {
 553         struct usb_serial_port *port = tty->driver_data;
 554         dbg("%s (%d) cmd = 0x%04x", __func__, port->number, cmd);
 555
 556         switch (cmd) {
 557         case TIOCMIWAIT:
 558                 dbg("%s (%d) TIOCMIWAIT", __func__,  port->number);
 559                 return wait_modem_info(port, arg);
 560
 561         default:
 562                 dbg("%s not supported = 0x%04x", __func__, cmd);
 563                 break;
 564         }
 565
 566         return -ENOIOCTLCMD;
 567 }
 568
 569 static int ch341_tiocmget(struct tty_struct *tty, struct file *file)
 570 {
 571         struct usb_serial_port *port = tty->driver_data;
 572         struct ch341_private *priv = usb_get_serial_port_data(port);
 573         unsigned long flags;
 574         u8 mcr;
 575         u8 status;
 576         unsigned int result;
 577
 578         dbg("%s (%d)", __func__, port->number);
 579
 580         spin_lock_irqsave(&priv->lock, flags);
 581         mcr = priv->line_control;
 582         status = priv->line_status;
 583         spin_unlock_irqrestore(&priv->lock, flags);
 584
 585         result = ((mcr & CH341_BIT_DTR)         ? TIOCM_DTR : 0)
 586                   | ((mcr & CH341_BIT_RTS)      ? TIOCM_RTS : 0)
 587                   | ((status & CH341_BIT_CTS)   ? TIOCM_CTS : 0)
 588                   | ((status & CH341_BIT_DSR)   ? TIOCM_DSR : 0)
 589                   | ((status & CH341_BIT_RI)    ? TIOCM_RI  : 0)
 590                   | ((status & CH341_BIT_DCD)   ? TIOCM_CD  : 0);
 591
 592         dbg("%s - result = %x", __func__, result);
 593
 594         return result;
 595 }
 596
 597
 598 static int ch341_reset_resume(struct usb_interface *intf)
 599 {
 600         struct usb_device *dev = interface_to_usbdev(intf);
 601         struct usb_serial *serial = NULL;
 602         struct ch341_private *priv;
 603
 604         serial = usb_get_intfdata(intf);
 605         priv = usb_get_serial_port_data(serial->port[0]);
 606
 607         /*reconfigure ch341 serial port after bus-reset*/
 608         ch341_configure(dev, priv);
 609
 610         usb_serial_resume(intf);
 611
 612         return 0;
 613 }
 614
 615 static struct usb_driver ch341_driver = {
 616         .name           = "ch341",
 617         .probe          = usb_serial_probe,
 618         .disconnect     = usb_serial_disconnect,
 619         .suspend        = usb_serial_suspend,
 620         .resume         = usb_serial_resume,
 621         .reset_resume   = ch341_reset_resume,
 622         .id_table       = id_table,
 623         .no_dynamic_id  = 1,
 624         .supports_autosuspend = 1,
 625 };
 626
 627 static struct usb_serial_driver ch341_device = {
 628         .driver = {
 629                 .owner  = THIS_MODULE,
 630                 .name   = "ch341-uart",
 631         },
 632         .id_table          = id_table,
 633         .usb_driver        = &ch341_driver,
 634         .num_ports         = 1,
 635         .open              = ch341_open,
 636         .dtr_rts           = ch341_dtr_rts,
 637         .carrier_raised    = ch341_carrier_raised,
 638         .close             = ch341_close,
 639         .ioctl             = ch341_ioctl,
 640         .set_termios       = ch341_set_termios,
 641         .break_ctl         = ch341_break_ctl,
 642         .tiocmget          = ch341_tiocmget,
 643         .tiocmset          = ch341_tiocmset,
 644         .read_int_callback = ch341_read_int_callback,
 645         .attach            = ch341_attach,
 646 };
 647
 648 static int __init ch341_init(void)
 649 {
 650         int retval;
 651
 652         retval = usb_serial_register(&ch341_device);
 653         if (retval)
 654                 return retval;
 655         retval = usb_register(&ch341_driver);
 656         if (retval)
 657                 usb_serial_deregister(&ch341_device);
 658         return retval;
 659 }
 660
 661 static void __exit ch341_exit(void)
 662 {
 663         usb_deregister(&ch341_driver);
 664         usb_serial_deregister(&ch341_device);
 665 }
 666
 667 module_init(ch341_init);
 668 module_exit(ch341_exit);
 669 MODULE_LICENSE("GPL");
 670
 671 module_param(debug, bool, S_IRUGO | S_IWUSR);
 672 MODULE_PARM_DESC(debug, "Debug enabled or not");
 673
 674 /* EOF ch341.c */