git.oblomov.eu Git - linux-2.6/blob - drivers/usb/serial/pl2303.c

   1 /*
   2  * Prolific PL2303 USB to serial adaptor driver
   3  *
   4  * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
   5  * Copyright (C) 2003 IBM Corp.
   6  *
   7  * Original driver for 2.2.x by anonymous
   8  *
   9  *      This program is free software; you can redistribute it and/or modify
  10  *      it under the terms of the GNU General Public License as published by
  11  *      the Free Software Foundation; either version 2 of the License.
  12  *
  13  * See Documentation/usb/usb-serial.txt for more information on using this driver
  14  *
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/errno.h>
  19 #include <linux/init.h>
  20 #include <linux/slab.h>
  21 #include <linux/tty.h>
  22 #include <linux/tty_driver.h>
  23 #include <linux/tty_flip.h>
  24 #include <linux/serial.h>
  25 #include <linux/module.h>
  26 #include <linux/moduleparam.h>
  27 #include <linux/spinlock.h>
  28 #include <asm/uaccess.h>
  29 #include <linux/usb.h>
  30 #include <linux/usb/serial.h>
  31 #include "pl2303.h"
  32
  33 /*
  34  * Version Information
  35  */
  36 #define DRIVER_DESC "Prolific PL2303 USB to serial adaptor driver"
  37
  38 static int debug;
  39
  40 #define PL2303_CLOSING_WAIT     (30*HZ)
  41
  42 #define PL2303_BUF_SIZE         1024
  43 #define PL2303_TMP_BUF_SIZE     1024
  44
  45 struct pl2303_buf {
  46         unsigned int    buf_size;
  47         char            *buf_buf;
  48         char            *buf_get;
  49         char            *buf_put;
  50 };
  51
  52 static struct usb_device_id id_table [] = {
  53         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
  54         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
  55         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
  56         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ3) },
  57         { USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_PHAROS) },
  58         { USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
  59         { USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID) },
  60         { USB_DEVICE(ATEN_VENDOR_ID2, ATEN_PRODUCT_ID) },
  61         { USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID) },
  62         { USB_DEVICE(ELCOM_VENDOR_ID, ELCOM_PRODUCT_ID_UCSGT) },
  63         { USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID) },
  64         { USB_DEVICE(ITEGNO_VENDOR_ID, ITEGNO_PRODUCT_ID_2080) },
  65         { USB_DEVICE(MA620_VENDOR_ID, MA620_PRODUCT_ID) },
  66         { USB_DEVICE(RATOC_VENDOR_ID, RATOC_PRODUCT_ID) },
  67         { USB_DEVICE(TRIPP_VENDOR_ID, TRIPP_PRODUCT_ID) },
  68         { USB_DEVICE(RADIOSHACK_VENDOR_ID, RADIOSHACK_PRODUCT_ID) },
  69         { USB_DEVICE(DCU10_VENDOR_ID, DCU10_PRODUCT_ID) },
  70         { USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
  71         { USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
  72         { USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
  73         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1) },
  74         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65) },
  75         { USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75) },
  76         { USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
  77         { USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
  78         { USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
  79         { USB_DEVICE(SAGEM_VENDOR_ID, SAGEM_PRODUCT_ID) },
  80         { USB_DEVICE(LEADTEK_VENDOR_ID, LEADTEK_9531_PRODUCT_ID) },
  81         { USB_DEVICE(SPEEDDRAGON_VENDOR_ID, SPEEDDRAGON_PRODUCT_ID) },
  82         { USB_DEVICE(DATAPILOT_U2_VENDOR_ID, DATAPILOT_U2_PRODUCT_ID) },
  83         { USB_DEVICE(BELKIN_VENDOR_ID, BELKIN_PRODUCT_ID) },
  84         { }                                     /* Terminating entry */
  85 };
  86
  87 MODULE_DEVICE_TABLE (usb, id_table);
  88
  89 static struct usb_driver pl2303_driver = {
  90         .name =         "pl2303",
  91         .probe =        usb_serial_probe,
  92         .disconnect =   usb_serial_disconnect,
  93         .id_table =     id_table,
  94         .no_dynamic_id =        1,
  95 };
  96
  97 #define SET_LINE_REQUEST_TYPE           0x21
  98 #define SET_LINE_REQUEST                0x20
  99
 100 #define SET_CONTROL_REQUEST_TYPE        0x21
 101 #define SET_CONTROL_REQUEST             0x22
 102 #define CONTROL_DTR                     0x01
 103 #define CONTROL_RTS                     0x02
 104
 105 #define BREAK_REQUEST_TYPE              0x21
 106 #define BREAK_REQUEST                   0x23
 107 #define BREAK_ON                        0xffff
 108 #define BREAK_OFF                       0x0000
 109
 110 #define GET_LINE_REQUEST_TYPE           0xa1
 111 #define GET_LINE_REQUEST                0x21
 112
 113 #define VENDOR_WRITE_REQUEST_TYPE       0x40
 114 #define VENDOR_WRITE_REQUEST            0x01
 115
 116 #define VENDOR_READ_REQUEST_TYPE        0xc0
 117 #define VENDOR_READ_REQUEST             0x01
 118
 119 #define UART_STATE                      0x08
 120 #define UART_STATE_TRANSIENT_MASK       0x74
 121 #define UART_DCD                        0x01
 122 #define UART_DSR                        0x02
 123 #define UART_BREAK_ERROR                0x04
 124 #define UART_RING                       0x08
 125 #define UART_FRAME_ERROR                0x10
 126 #define UART_PARITY_ERROR               0x20
 127 #define UART_OVERRUN_ERROR              0x40
 128 #define UART_CTS                        0x80
 129
 130 /* function prototypes for a PL2303 serial converter */
 131 static int pl2303_open (struct usb_serial_port *port, struct file *filp);
 132 static void pl2303_close (struct usb_serial_port *port, struct file *filp);
 133 static void pl2303_set_termios (struct usb_serial_port *port,
 134                                 struct termios *old);
 135 static int pl2303_ioctl (struct usb_serial_port *port, struct file *file,
 136                          unsigned int cmd, unsigned long arg);
 137 static void pl2303_read_int_callback (struct urb *urb, struct pt_regs *regs);
 138 static void pl2303_read_bulk_callback (struct urb *urb, struct pt_regs *regs);
 139 static void pl2303_write_bulk_callback (struct urb *urb, struct pt_regs *regs);
 140 static int pl2303_write (struct usb_serial_port *port,
 141                          const unsigned char *buf, int count);
 142 static void pl2303_send (struct usb_serial_port *port);
 143 static int pl2303_write_room(struct usb_serial_port *port);
 144 static int pl2303_chars_in_buffer(struct usb_serial_port *port);
 145 static void pl2303_break_ctl(struct usb_serial_port *port,int break_state);
 146 static int pl2303_tiocmget (struct usb_serial_port *port, struct file *file);
 147 static int pl2303_tiocmset (struct usb_serial_port *port, struct file *file,
 148                             unsigned int set, unsigned int clear);
 149 static int pl2303_startup (struct usb_serial *serial);
 150 static void pl2303_shutdown (struct usb_serial *serial);
 151 static struct pl2303_buf *pl2303_buf_alloc(unsigned int size);
 152 static void pl2303_buf_free(struct pl2303_buf *pb);
 153 static void pl2303_buf_clear(struct pl2303_buf *pb);
 154 static unsigned int pl2303_buf_data_avail(struct pl2303_buf *pb);
 155 static unsigned int pl2303_buf_space_avail(struct pl2303_buf *pb);
 156 static unsigned int pl2303_buf_put(struct pl2303_buf *pb, const char *buf,
 157         unsigned int count);
 158 static unsigned int pl2303_buf_get(struct pl2303_buf *pb, char *buf,
 159         unsigned int count);
 160
 161
 162 /* All of the device info needed for the PL2303 SIO serial converter */
 163 static struct usb_serial_driver pl2303_device = {
 164         .driver = {
 165                 .owner =        THIS_MODULE,
 166                 .name =         "pl2303",
 167         },
 168         .id_table =             id_table,
 169         .num_interrupt_in =     NUM_DONT_CARE,
 170         .num_bulk_in =          1,
 171         .num_bulk_out =         1,
 172         .num_ports =            1,
 173         .open =                 pl2303_open,
 174         .close =                pl2303_close,
 175         .write =                pl2303_write,
 176         .ioctl =                pl2303_ioctl,
 177         .break_ctl =            pl2303_break_ctl,
 178         .set_termios =          pl2303_set_termios,
 179         .tiocmget =             pl2303_tiocmget,
 180         .tiocmset =             pl2303_tiocmset,
 181         .read_bulk_callback =   pl2303_read_bulk_callback,
 182         .read_int_callback =    pl2303_read_int_callback,
 183         .write_bulk_callback =  pl2303_write_bulk_callback,
 184         .write_room =           pl2303_write_room,
 185         .chars_in_buffer =      pl2303_chars_in_buffer,
 186         .attach =               pl2303_startup,
 187         .shutdown =             pl2303_shutdown,
 188 };
 189
 190 enum pl2303_type {
 191         type_0,         /* don't know the difference between type 0 and */
 192         type_1,         /* type 1, until someone from prolific tells us... */
 193         HX,             /* HX version of the pl2303 chip */
 194 };
 195
 196 struct pl2303_private {
 197         spinlock_t lock;
 198         struct pl2303_buf *buf;
 199         int write_urb_in_use;
 200         wait_queue_head_t delta_msr_wait;
 201         u8 line_control;
 202         u8 line_status;
 203         u8 termios_initialized;
 204         enum pl2303_type type;
 205 };
 206
 207
 208 static int pl2303_startup (struct usb_serial *serial)
 209 {
 210         struct pl2303_private *priv;
 211         enum pl2303_type type = type_0;
 212         int i;
 213
 214         if (serial->dev->descriptor.bDeviceClass == 0x02)
 215                 type = type_0;
 216         else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
 217                 type = HX;
 218         else if (serial->dev->descriptor.bDeviceClass == 0x00)
 219                 type = type_1;
 220         else if (serial->dev->descriptor.bDeviceClass == 0xFF)
 221                 type = type_1;
 222         dbg("device type: %d", type);
 223
 224         for (i = 0; i < serial->num_ports; ++i) {
 225                 priv = kzalloc(sizeof(struct pl2303_private), GFP_KERNEL);
 226                 if (!priv)
 227                         goto cleanup;
 228                 spin_lock_init(&priv->lock);
 229                 priv->buf = pl2303_buf_alloc(PL2303_BUF_SIZE);
 230                 if (priv->buf == NULL) {
 231                         kfree(priv);
 232                         goto cleanup;
 233                 }
 234                 init_waitqueue_head(&priv->delta_msr_wait);
 235                 priv->type = type;
 236                 usb_set_serial_port_data(serial->port[i], priv);
 237         }
 238         return 0;
 239
 240 cleanup:
 241         for (--i; i>=0; --i) {
 242                 priv = usb_get_serial_port_data(serial->port[i]);
 243                 pl2303_buf_free(priv->buf);
 244                 kfree(priv);
 245                 usb_set_serial_port_data(serial->port[i], NULL);
 246         }
 247         return -ENOMEM;
 248 }
 249
 250 static int set_control_lines (struct usb_device *dev, u8 value)
 251 {
 252         int retval;
 253
 254         retval = usb_control_msg (dev, usb_sndctrlpipe (dev, 0),
 255                                   SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
 256                                   value, 0, NULL, 0, 100);
 257         dbg("%s - value = %d, retval = %d", __FUNCTION__, value, retval);
 258         return retval;
 259 }
 260
 261 static int pl2303_write (struct usb_serial_port *port,  const unsigned char *buf, int count)
 262 {
 263         struct pl2303_private *priv = usb_get_serial_port_data(port);
 264         unsigned long flags;
 265
 266         dbg("%s - port %d, %d bytes", __FUNCTION__, port->number, count);
 267
 268         if (!count)
 269                 return count;
 270
 271         spin_lock_irqsave(&priv->lock, flags);
 272         count = pl2303_buf_put(priv->buf, buf, count);
 273         spin_unlock_irqrestore(&priv->lock, flags);
 274
 275         pl2303_send(port);
 276
 277         return count;
 278 }
 279
 280 static void pl2303_send(struct usb_serial_port *port)
 281 {
 282         int count, result;
 283         struct pl2303_private *priv = usb_get_serial_port_data(port);
 284         unsigned long flags;
 285
 286         dbg("%s - port %d", __FUNCTION__, port->number);
 287
 288         spin_lock_irqsave(&priv->lock, flags);
 289
 290         if (priv->write_urb_in_use) {
 291                 spin_unlock_irqrestore(&priv->lock, flags);
 292                 return;
 293         }
 294
 295         count = pl2303_buf_get(priv->buf, port->write_urb->transfer_buffer,
 296                 port->bulk_out_size);
 297
 298         if (count == 0) {
 299                 spin_unlock_irqrestore(&priv->lock, flags);
 300                 return;
 301         }
 302
 303         priv->write_urb_in_use = 1;
 304
 305         spin_unlock_irqrestore(&priv->lock, flags);
 306
 307         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, port->write_urb->transfer_buffer);
 308
 309         port->write_urb->transfer_buffer_length = count;
 310         port->write_urb->dev = port->serial->dev;
 311         result = usb_submit_urb (port->write_urb, GFP_ATOMIC);
 312         if (result) {
 313                 dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __FUNCTION__, result);
 314                 priv->write_urb_in_use = 0;
 315                 // TODO: reschedule pl2303_send
 316         }
 317
 318         usb_serial_port_softint(port);
 319 }
 320
 321 static int pl2303_write_room(struct usb_serial_port *port)
 322 {
 323         struct pl2303_private *priv = usb_get_serial_port_data(port);
 324         int room = 0;
 325         unsigned long flags;
 326
 327         dbg("%s - port %d", __FUNCTION__, port->number);
 328
 329         spin_lock_irqsave(&priv->lock, flags);
 330         room = pl2303_buf_space_avail(priv->buf);
 331         spin_unlock_irqrestore(&priv->lock, flags);
 332
 333         dbg("%s - returns %d", __FUNCTION__, room);
 334         return room;
 335 }
 336
 337 static int pl2303_chars_in_buffer(struct usb_serial_port *port)
 338 {
 339         struct pl2303_private *priv = usb_get_serial_port_data(port);
 340         int chars = 0;
 341         unsigned long flags;
 342
 343         dbg("%s - port %d", __FUNCTION__, port->number);
 344
 345         spin_lock_irqsave(&priv->lock, flags);
 346         chars = pl2303_buf_data_avail(priv->buf);
 347         spin_unlock_irqrestore(&priv->lock, flags);
 348
 349         dbg("%s - returns %d", __FUNCTION__, chars);
 350         return chars;
 351 }
 352
 353 static void pl2303_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 354 {
 355         struct usb_serial *serial = port->serial;
 356         struct pl2303_private *priv = usb_get_serial_port_data(port);
 357         unsigned long flags;
 358         unsigned int cflag;
 359         unsigned char *buf;
 360         int baud;
 361         int i;
 362         u8 control;
 363
 364         dbg("%s -  port %d", __FUNCTION__, port->number);
 365
 366         if ((!port->tty) || (!port->tty->termios)) {
 367                 dbg("%s - no tty structures", __FUNCTION__);
 368                 return;
 369         }
 370
 371         spin_lock_irqsave(&priv->lock, flags);
 372         if (!priv->termios_initialized) {
 373                 *(port->tty->termios) = tty_std_termios;
 374                 port->tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 375                 priv->termios_initialized = 1;
 376         }
 377         spin_unlock_irqrestore(&priv->lock, flags);
 378
 379         cflag = port->tty->termios->c_cflag;
 380         /* check that they really want us to change something */
 381         if (old_termios) {
 382                 if ((cflag == old_termios->c_cflag) &&
 383                     (RELEVANT_IFLAG(port->tty->termios->c_iflag) == RELEVANT_IFLAG(old_termios->c_iflag))) {
 384                     dbg("%s - nothing to change...", __FUNCTION__);
 385                     return;
 386                 }
 387         }
 388
 389         buf = kzalloc (7, GFP_KERNEL);
 390         if (!buf) {
 391                 dev_err(&port->dev, "%s - out of memory.\n", __FUNCTION__);
 392                 return;
 393         }
 394
 395         i = usb_control_msg (serial->dev, usb_rcvctrlpipe (serial->dev, 0),
 396                              GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
 397                              0, 0, buf, 7, 100);
 398         dbg ("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
 399              buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
 400
 401
 402         if (cflag & CSIZE) {
 403                 switch (cflag & CSIZE) {
 404                         case CS5:       buf[6] = 5;     break;
 405                         case CS6:       buf[6] = 6;     break;
 406                         case CS7:       buf[6] = 7;     break;
 407                         default:
 408                         case CS8:       buf[6] = 8;     break;
 409                 }
 410                 dbg("%s - data bits = %d", __FUNCTION__, buf[6]);
 411         }
 412
 413         baud = 0;
 414         switch (cflag & CBAUD) {
 415                 case B0:        baud = 0;       break;
 416                 case B75:       baud = 75;      break;
 417                 case B150:      baud = 150;     break;
 418                 case B300:      baud = 300;     break;
 419                 case B600:      baud = 600;     break;
 420                 case B1200:     baud = 1200;    break;
 421                 case B1800:     baud = 1800;    break;
 422                 case B2400:     baud = 2400;    break;
 423                 case B4800:     baud = 4800;    break;
 424                 case B9600:     baud = 9600;    break;
 425                 case B19200:    baud = 19200;   break;
 426                 case B38400:    baud = 38400;   break;
 427                 case B57600:    baud = 57600;   break;
 428                 case B115200:   baud = 115200;  break;
 429                 case B230400:   baud = 230400;  break;
 430                 case B460800:   baud = 460800;  break;
 431                 default:
 432                         dev_err(&port->dev, "pl2303 driver does not support the baudrate requested (fix it)\n");
 433                         break;
 434         }
 435         dbg("%s - baud = %d", __FUNCTION__, baud);
 436         if (baud) {
 437                 buf[0] = baud & 0xff;
 438                 buf[1] = (baud >> 8) & 0xff;
 439                 buf[2] = (baud >> 16) & 0xff;
 440                 buf[3] = (baud >> 24) & 0xff;
 441         }
 442
 443         /* For reference buf[4]=0 is 1 stop bits */
 444         /* For reference buf[4]=1 is 1.5 stop bits */
 445         /* For reference buf[4]=2 is 2 stop bits */
 446         if (cflag & CSTOPB) {
 447                 buf[4] = 2;
 448                 dbg("%s - stop bits = 2", __FUNCTION__);
 449         } else {
 450                 buf[4] = 0;
 451                 dbg("%s - stop bits = 1", __FUNCTION__);
 452         }
 453
 454         if (cflag & PARENB) {
 455                 /* For reference buf[5]=0 is none parity */
 456                 /* For reference buf[5]=1 is odd parity */
 457                 /* For reference buf[5]=2 is even parity */
 458                 /* For reference buf[5]=3 is mark parity */
 459                 /* For reference buf[5]=4 is space parity */
 460                 if (cflag & PARODD) {
 461                         buf[5] = 1;
 462                         dbg("%s - parity = odd", __FUNCTION__);
 463                 } else {
 464                         buf[5] = 2;
 465                         dbg("%s - parity = even", __FUNCTION__);
 466                 }
 467         } else {
 468                 buf[5] = 0;
 469                 dbg("%s - parity = none", __FUNCTION__);
 470         }
 471
 472         i = usb_control_msg (serial->dev, usb_sndctrlpipe (serial->dev, 0),
 473                              SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
 474                              0, 0, buf, 7, 100);
 475         dbg ("0x21:0x20:0:0  %d", i);
 476
 477         /* change control lines if we are switching to or from B0 */
 478         spin_lock_irqsave(&priv->lock, flags);
 479         control = priv->line_control;
 480         if ((cflag & CBAUD) == B0)
 481                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 482         else
 483                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 484         if (control != priv->line_control) {
 485                 control = priv->line_control;
 486                 spin_unlock_irqrestore(&priv->lock, flags);
 487                 set_control_lines(serial->dev, control);
 488         } else {
 489                 spin_unlock_irqrestore(&priv->lock, flags);
 490         }
 491
 492         buf[0] = buf[1] = buf[2] = buf[3] = buf[4] = buf[5] = buf[6] = 0;
 493
 494         i = usb_control_msg (serial->dev, usb_rcvctrlpipe (serial->dev, 0),
 495                              GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
 496                              0, 0, buf, 7, 100);
 497         dbg ("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
 498              buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
 499
 500         if (cflag & CRTSCTS) {
 501                 __u16 index;
 502                 if (priv->type == HX)
 503                         index = 0x61;
 504                 else
 505                         index = 0x41;
 506                 i = usb_control_msg(serial->dev,
 507                                     usb_sndctrlpipe(serial->dev, 0),
 508                                     VENDOR_WRITE_REQUEST,
 509                                     VENDOR_WRITE_REQUEST_TYPE,
 510                                     0x0, index, NULL, 0, 100);
 511                 dbg ("0x40:0x1:0x0:0x%x  %d", index, i);
 512         }
 513
 514         kfree (buf);
 515 }
 516
 517 static int pl2303_open (struct usb_serial_port *port, struct file *filp)
 518 {
 519         struct termios tmp_termios;
 520         struct usb_serial *serial = port->serial;
 521         struct pl2303_private *priv = usb_get_serial_port_data(port);
 522         unsigned char *buf;
 523         int result;
 524
 525         dbg("%s -  port %d", __FUNCTION__, port->number);
 526
 527         if (priv->type != HX) {
 528                 usb_clear_halt(serial->dev, port->write_urb->pipe);
 529                 usb_clear_halt(serial->dev, port->read_urb->pipe);
 530         }
 531
 532         buf = kmalloc(10, GFP_KERNEL);
 533         if (buf==NULL)
 534                 return -ENOMEM;
 535
 536 #define FISH(a,b,c,d)                                                           \
 537         result=usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev,0),     \
 538                                b, a, c, d, buf, 1, 100);                        \
 539         dbg("0x%x:0x%x:0x%x:0x%x  %d - %x",a,b,c,d,result,buf[0]);
 540
 541 #define SOUP(a,b,c,d)                                                           \
 542         result=usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev,0),     \
 543                                b, a, c, d, NULL, 0, 100);                       \
 544         dbg("0x%x:0x%x:0x%x:0x%x  %d",a,b,c,d,result);
 545
 546         FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
 547         SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 0);
 548         FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
 549         FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
 550         FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
 551         SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 1);
 552         FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
 553         FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
 554         SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0, 1);
 555         SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 1, 0);
 556
 557         if (priv->type == HX) {
 558                 /* HX chip */
 559                 SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x44);
 560                 /* reset upstream data pipes */
 561                 SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 8, 0);
 562                 SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 9, 0);
 563         } else {
 564                 SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x24);
 565         }
 566
 567         kfree(buf);
 568
 569         /* Setup termios */
 570         if (port->tty) {
 571                 pl2303_set_termios (port, &tmp_termios);
 572         }
 573
 574         //FIXME: need to assert RTS and DTR if CRTSCTS off
 575
 576         dbg("%s - submitting read urb", __FUNCTION__);
 577         port->read_urb->dev = serial->dev;
 578         result = usb_submit_urb (port->read_urb, GFP_KERNEL);
 579         if (result) {
 580                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 581                 pl2303_close (port, NULL);
 582                 return -EPROTO;
 583         }
 584
 585         dbg("%s - submitting interrupt urb", __FUNCTION__);
 586         port->interrupt_in_urb->dev = serial->dev;
 587         result = usb_submit_urb (port->interrupt_in_urb, GFP_KERNEL);
 588         if (result) {
 589                 dev_err(&port->dev, "%s - failed submitting interrupt urb, error %d\n", __FUNCTION__, result);
 590                 pl2303_close (port, NULL);
 591                 return -EPROTO;
 592         }
 593         return 0;
 594 }
 595
 596
 597 static void pl2303_close (struct usb_serial_port *port, struct file *filp)
 598 {
 599         struct pl2303_private *priv = usb_get_serial_port_data(port);
 600         unsigned long flags;
 601         unsigned int c_cflag;
 602         int bps;
 603         long timeout;
 604         wait_queue_t wait;
 605
 606         dbg("%s - port %d", __FUNCTION__, port->number);
 607
 608         /* wait for data to drain from the buffer */
 609         spin_lock_irqsave(&priv->lock, flags);
 610         timeout = PL2303_CLOSING_WAIT;
 611         init_waitqueue_entry(&wait, current);
 612         add_wait_queue(&port->tty->write_wait, &wait);
 613         for (;;) {
 614                 set_current_state(TASK_INTERRUPTIBLE);
 615                 if (pl2303_buf_data_avail(priv->buf) == 0
 616                 || timeout == 0 || signal_pending(current)
 617                 || !usb_get_intfdata(port->serial->interface))  /* disconnect */
 618                         break;
 619                 spin_unlock_irqrestore(&priv->lock, flags);
 620                 timeout = schedule_timeout(timeout);
 621                 spin_lock_irqsave(&priv->lock, flags);
 622         }
 623         set_current_state(TASK_RUNNING);
 624         remove_wait_queue(&port->tty->write_wait, &wait);
 625         /* clear out any remaining data in the buffer */
 626         pl2303_buf_clear(priv->buf);
 627         spin_unlock_irqrestore(&priv->lock, flags);
 628
 629         /* wait for characters to drain from the device */
 630         /* (this is long enough for the entire 256 byte */
 631         /* pl2303 hardware buffer to drain with no flow */
 632         /* control for data rates of 1200 bps or more, */
 633         /* for lower rates we should really know how much */
 634         /* data is in the buffer to compute a delay */
 635         /* that is not unnecessarily long) */
 636         bps = tty_get_baud_rate(port->tty);
 637         if (bps > 1200)
 638                 timeout = max((HZ*2560)/bps,HZ/10);
 639         else
 640                 timeout = 2*HZ;
 641         schedule_timeout_interruptible(timeout);
 642
 643         /* shutdown our urbs */
 644         dbg("%s - shutting down urbs", __FUNCTION__);
 645         usb_kill_urb(port->write_urb);
 646         usb_kill_urb(port->read_urb);
 647         usb_kill_urb(port->interrupt_in_urb);
 648
 649         if (port->tty) {
 650                 c_cflag = port->tty->termios->c_cflag;
 651                 if (c_cflag & HUPCL) {
 652                         /* drop DTR and RTS */
 653                         spin_lock_irqsave(&priv->lock, flags);
 654                         priv->line_control = 0;
 655                         spin_unlock_irqrestore (&priv->lock, flags);
 656                         set_control_lines (port->serial->dev, 0);
 657                 }
 658         }
 659 }
 660
 661 static int pl2303_tiocmset (struct usb_serial_port *port, struct file *file,
 662                             unsigned int set, unsigned int clear)
 663 {
 664         struct pl2303_private *priv = usb_get_serial_port_data(port);
 665         unsigned long flags;
 666         u8 control;
 667
 668         if (!usb_get_intfdata(port->serial->interface))
 669                 return -ENODEV;
 670
 671         spin_lock_irqsave (&priv->lock, flags);
 672         if (set & TIOCM_RTS)
 673                 priv->line_control |= CONTROL_RTS;
 674         if (set & TIOCM_DTR)
 675                 priv->line_control |= CONTROL_DTR;
 676         if (clear & TIOCM_RTS)
 677                 priv->line_control &= ~CONTROL_RTS;
 678         if (clear & TIOCM_DTR)
 679                 priv->line_control &= ~CONTROL_DTR;
 680         control = priv->line_control;
 681         spin_unlock_irqrestore (&priv->lock, flags);
 682
 683         return set_control_lines (port->serial->dev, control);
 684 }
 685
 686 static int pl2303_tiocmget (struct usb_serial_port *port, struct file *file)
 687 {
 688         struct pl2303_private *priv = usb_get_serial_port_data(port);
 689         unsigned long flags;
 690         unsigned int mcr;
 691         unsigned int status;
 692         unsigned int result;
 693
 694         dbg("%s (%d)", __FUNCTION__, port->number);
 695
 696         if (!usb_get_intfdata(port->serial->interface))
 697                 return -ENODEV;
 698
 699         spin_lock_irqsave (&priv->lock, flags);
 700         mcr = priv->line_control;
 701         status = priv->line_status;
 702         spin_unlock_irqrestore (&priv->lock, flags);
 703
 704         result = ((mcr & CONTROL_DTR)           ? TIOCM_DTR : 0)
 705                   | ((mcr & CONTROL_RTS)        ? TIOCM_RTS : 0)
 706                   | ((status & UART_CTS)        ? TIOCM_CTS : 0)
 707                   | ((status & UART_DSR)        ? TIOCM_DSR : 0)
 708                   | ((status & UART_RING)       ? TIOCM_RI  : 0)
 709                   | ((status & UART_DCD)        ? TIOCM_CD  : 0);
 710
 711         dbg("%s - result = %x", __FUNCTION__, result);
 712
 713         return result;
 714 }
 715
 716 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 717 {
 718         struct pl2303_private *priv = usb_get_serial_port_data(port);
 719         unsigned long flags;
 720         unsigned int prevstatus;
 721         unsigned int status;
 722         unsigned int changed;
 723
 724         spin_lock_irqsave (&priv->lock, flags);
 725         prevstatus = priv->line_status;
 726         spin_unlock_irqrestore (&priv->lock, flags);
 727
 728         while (1) {
 729                 interruptible_sleep_on(&priv->delta_msr_wait);
 730                 /* see if a signal did it */
 731                 if (signal_pending(current))
 732                         return -ERESTARTSYS;
 733
 734                 spin_lock_irqsave (&priv->lock, flags);
 735                 status = priv->line_status;
 736                 spin_unlock_irqrestore (&priv->lock, flags);
 737
 738                 changed=prevstatus^status;
 739
 740                 if (((arg & TIOCM_RNG) && (changed & UART_RING)) ||
 741                     ((arg & TIOCM_DSR) && (changed & UART_DSR)) ||
 742                     ((arg & TIOCM_CD)  && (changed & UART_DCD)) ||
 743                     ((arg & TIOCM_CTS) && (changed & UART_CTS)) ) {
 744                         return 0;
 745                 }
 746                 prevstatus = status;
 747         }
 748         /* NOTREACHED */
 749         return 0;
 750 }
 751
 752 static int pl2303_ioctl (struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg)
 753 {
 754         dbg("%s (%d) cmd = 0x%04x", __FUNCTION__, port->number, cmd);
 755
 756         switch (cmd) {
 757                 case TIOCMIWAIT:
 758                         dbg("%s (%d) TIOCMIWAIT", __FUNCTION__,  port->number);
 759                         return wait_modem_info(port, arg);
 760
 761                 default:
 762                         dbg("%s not supported = 0x%04x", __FUNCTION__, cmd);
 763                         break;
 764         }
 765
 766         return -ENOIOCTLCMD;
 767 }
 768
 769 static void pl2303_break_ctl (struct usb_serial_port *port, int break_state)
 770 {
 771         struct usb_serial *serial = port->serial;
 772         u16 state;
 773         int result;
 774
 775         dbg("%s - port %d", __FUNCTION__, port->number);
 776
 777         if (break_state == 0)
 778                 state = BREAK_OFF;
 779         else
 780                 state = BREAK_ON;
 781         dbg("%s - turning break %s", __FUNCTION__, state==BREAK_OFF ? "off" : "on");
 782
 783         result = usb_control_msg (serial->dev, usb_sndctrlpipe (serial->dev, 0),
 784                                   BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
 785                                   0, NULL, 0, 100);
 786         if (result)
 787                 dbg("%s - error sending break = %d", __FUNCTION__, result);
 788 }
 789
 790
 791 static void pl2303_shutdown (struct usb_serial *serial)
 792 {
 793         int i;
 794         struct pl2303_private *priv;
 795
 796         dbg("%s", __FUNCTION__);
 797
 798         for (i = 0; i < serial->num_ports; ++i) {
 799                 priv = usb_get_serial_port_data(serial->port[i]);
 800                 if (priv) {
 801                         pl2303_buf_free(priv->buf);
 802                         kfree(priv);
 803                         usb_set_serial_port_data(serial->port[i], NULL);
 804                 }
 805         }
 806 }
 807
 808 static void pl2303_update_line_status(struct usb_serial_port *port,
 809                                       unsigned char *data,
 810                                       unsigned int actual_length)
 811 {
 812
 813         struct pl2303_private *priv = usb_get_serial_port_data(port);
 814         unsigned long flags;
 815         u8 status_idx = UART_STATE;
 816         u8 length = UART_STATE + 1;
 817
 818         if ((le16_to_cpu(port->serial->dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
 819             (le16_to_cpu(port->serial->dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_X65 ||
 820              le16_to_cpu(port->serial->dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_SX1 ||
 821              le16_to_cpu(port->serial->dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_X75)) {
 822                 length = 1;
 823                 status_idx = 0;
 824         }
 825
 826         if (actual_length < length)
 827                 goto exit;
 828
 829         /* Save off the uart status for others to look at */
 830         spin_lock_irqsave(&priv->lock, flags);
 831         priv->line_status = data[status_idx];
 832         spin_unlock_irqrestore(&priv->lock, flags);
 833         wake_up_interruptible (&priv->delta_msr_wait);
 834
 835 exit:
 836         return;
 837 }
 838
 839 static void pl2303_read_int_callback (struct urb *urb, struct pt_regs *regs)
 840 {
 841         struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
 842         unsigned char *data = urb->transfer_buffer;
 843         unsigned int actual_length = urb->actual_length;
 844         int status;
 845
 846         dbg("%s (%d)", __FUNCTION__, port->number);
 847
 848         switch (urb->status) {
 849         case 0:
 850                 /* success */
 851                 break;
 852         case -ECONNRESET:
 853         case -ENOENT:
 854         case -ESHUTDOWN:
 855                 /* this urb is terminated, clean up */
 856                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 857                 return;
 858         default:
 859                 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 860                 goto exit;
 861         }
 862
 863         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, urb->transfer_buffer);
 864         pl2303_update_line_status(port, data, actual_length);
 865
 866 exit:
 867         status = usb_submit_urb (urb, GFP_ATOMIC);
 868         if (status)
 869                 dev_err(&urb->dev->dev, "%s - usb_submit_urb failed with result %d\n",
 870                         __FUNCTION__, status);
 871 }
 872
 873
 874 static void pl2303_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 875 {
 876         struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
 877         struct pl2303_private *priv = usb_get_serial_port_data(port);
 878         struct tty_struct *tty;
 879         unsigned char *data = urb->transfer_buffer;
 880         unsigned long flags;
 881         int i;
 882         int result;
 883         u8 status;
 884         char tty_flag;
 885
 886         dbg("%s - port %d", __FUNCTION__, port->number);
 887
 888         if (urb->status) {
 889                 dbg("%s - urb->status = %d", __FUNCTION__, urb->status);
 890                 if (!port->open_count) {
 891                         dbg("%s - port is closed, exiting.", __FUNCTION__);
 892                         return;
 893                 }
 894                 if (urb->status == -EPROTO) {
 895                         /* PL2303 mysteriously fails with -EPROTO reschedule the read */
 896                         dbg("%s - caught -EPROTO, resubmitting the urb", __FUNCTION__);
 897                         urb->status = 0;
 898                         urb->dev = port->serial->dev;
 899                         result = usb_submit_urb(urb, GFP_ATOMIC);
 900                         if (result)
 901                                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 902                         return;
 903                 }
 904                 dbg("%s - unable to handle the error, exiting.", __FUNCTION__);
 905                 return;
 906         }
 907
 908         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
 909
 910         /* get tty_flag from status */
 911         tty_flag = TTY_NORMAL;
 912
 913         spin_lock_irqsave(&priv->lock, flags);
 914         status = priv->line_status;
 915         priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
 916         spin_unlock_irqrestore(&priv->lock, flags);
 917         wake_up_interruptible (&priv->delta_msr_wait);
 918
 919         /* break takes precedence over parity, */
 920         /* which takes precedence over framing errors */
 921         if (status & UART_BREAK_ERROR )
 922                 tty_flag = TTY_BREAK;
 923         else if (status & UART_PARITY_ERROR)
 924                 tty_flag = TTY_PARITY;
 925         else if (status & UART_FRAME_ERROR)
 926                 tty_flag = TTY_FRAME;
 927         dbg("%s - tty_flag = %d", __FUNCTION__, tty_flag);
 928
 929         tty = port->tty;
 930         if (tty && urb->actual_length) {
 931                 tty_buffer_request_room(tty, urb->actual_length + 1);
 932                 /* overrun is special, not associated with a char */
 933                 if (status & UART_OVERRUN_ERROR)
 934                         tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 935                 for (i = 0; i < urb->actual_length; ++i)
 936                         tty_insert_flip_char (tty, data[i], tty_flag);
 937                 tty_flip_buffer_push (tty);
 938         }
 939
 940         /* Schedule the next read _if_ we are still open */
 941         if (port->open_count) {
 942                 urb->dev = port->serial->dev;
 943                 result = usb_submit_urb(urb, GFP_ATOMIC);
 944                 if (result)
 945                         dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 946         }
 947
 948         return;
 949 }
 950
 951
 952
 953 static void pl2303_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 954 {
 955         struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
 956         struct pl2303_private *priv = usb_get_serial_port_data(port);
 957         int result;
 958
 959         dbg("%s - port %d", __FUNCTION__, port->number);
 960
 961         switch (urb->status) {
 962         case 0:
 963                 /* success */
 964                 break;
 965         case -ECONNRESET:
 966         case -ENOENT:
 967         case -ESHUTDOWN:
 968                 /* this urb is terminated, clean up */
 969                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 970                 priv->write_urb_in_use = 0;
 971                 return;
 972         default:
 973                 /* error in the urb, so we have to resubmit it */
 974                 dbg("%s - Overflow in write", __FUNCTION__);
 975                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 976                 port->write_urb->transfer_buffer_length = 1;
 977                 port->write_urb->dev = port->serial->dev;
 978                 result = usb_submit_urb (port->write_urb, GFP_ATOMIC);
 979                 if (result)
 980                         dev_err(&urb->dev->dev, "%s - failed resubmitting write urb, error %d\n", __FUNCTION__, result);
 981                 else
 982                         return;
 983         }
 984
 985         priv->write_urb_in_use = 0;
 986
 987         /* send any buffered data */
 988         pl2303_send(port);
 989 }
 990
 991
 992 /*
 993  * pl2303_buf_alloc
 994  *
 995  * Allocate a circular buffer and all associated memory.
 996  */
 997
 998 static struct pl2303_buf *pl2303_buf_alloc(unsigned int size)
 999 {
1000
1001         struct pl2303_buf *pb;
1002
1003
1004         if (size == 0)
1005                 return NULL;
1006
1007         pb = (struct pl2303_buf *)kmalloc(sizeof(struct pl2303_buf), GFP_KERNEL);
1008         if (pb == NULL)
1009                 return NULL;
1010
1011         pb->buf_buf = kmalloc(size, GFP_KERNEL);
1012         if (pb->buf_buf == NULL) {
1013                 kfree(pb);
1014                 return NULL;
1015         }
1016
1017         pb->buf_size = size;
1018         pb->buf_get = pb->buf_put = pb->buf_buf;
1019
1020         return pb;
1021
1022 }
1023
1024
1025 /*
1026  * pl2303_buf_free
1027  *
1028  * Free the buffer and all associated memory.
1029  */
1030
1031 static void pl2303_buf_free(struct pl2303_buf *pb)
1032 {
1033         if (pb) {
1034                 kfree(pb->buf_buf);
1035                 kfree(pb);
1036         }
1037 }
1038
1039
1040 /*
1041  * pl2303_buf_clear
1042  *
1043  * Clear out all data in the circular buffer.
1044  */
1045
1046 static void pl2303_buf_clear(struct pl2303_buf *pb)
1047 {
1048         if (pb != NULL)
1049                 pb->buf_get = pb->buf_put;
1050                 /* equivalent to a get of all data available */
1051 }
1052
1053
1054 /*
1055  * pl2303_buf_data_avail
1056  *
1057  * Return the number of bytes of data available in the circular
1058  * buffer.
1059  */
1060
1061 static unsigned int pl2303_buf_data_avail(struct pl2303_buf *pb)
1062 {
1063         if (pb != NULL)
1064                 return ((pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size);
1065         else
1066                 return 0;
1067 }
1068
1069
1070 /*
1071  * pl2303_buf_space_avail
1072  *
1073  * Return the number of bytes of space available in the circular
1074  * buffer.
1075  */
1076
1077 static unsigned int pl2303_buf_space_avail(struct pl2303_buf *pb)
1078 {
1079         if (pb != NULL)
1080                 return ((pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size);
1081         else
1082                 return 0;
1083 }
1084
1085
1086 /*
1087  * pl2303_buf_put
1088  *
1089  * Copy data data from a user buffer and put it into the circular buffer.
1090  * Restrict to the amount of space available.
1091  *
1092  * Return the number of bytes copied.
1093  */
1094
1095 static unsigned int pl2303_buf_put(struct pl2303_buf *pb, const char *buf,
1096         unsigned int count)
1097 {
1098
1099         unsigned int len;
1100
1101
1102         if (pb == NULL)
1103                 return 0;
1104
1105         len  = pl2303_buf_space_avail(pb);
1106         if (count > len)
1107                 count = len;
1108
1109         if (count == 0)
1110                 return 0;
1111
1112         len = pb->buf_buf + pb->buf_size - pb->buf_put;
1113         if (count > len) {
1114                 memcpy(pb->buf_put, buf, len);
1115                 memcpy(pb->buf_buf, buf+len, count - len);
1116                 pb->buf_put = pb->buf_buf + count - len;
1117         } else {
1118                 memcpy(pb->buf_put, buf, count);
1119                 if (count < len)
1120                         pb->buf_put += count;
1121                 else /* count == len */
1122                         pb->buf_put = pb->buf_buf;
1123         }
1124
1125         return count;
1126
1127 }
1128
1129
1130 /*
1131  * pl2303_buf_get
1132  *
1133  * Get data from the circular buffer and copy to the given buffer.
1134  * Restrict to the amount of data available.
1135  *
1136  * Return the number of bytes copied.
1137  */
1138
1139 static unsigned int pl2303_buf_get(struct pl2303_buf *pb, char *buf,
1140         unsigned int count)
1141 {
1142
1143         unsigned int len;
1144
1145
1146         if (pb == NULL)
1147                 return 0;
1148
1149         len = pl2303_buf_data_avail(pb);
1150         if (count > len)
1151                 count = len;
1152
1153         if (count == 0)
1154                 return 0;
1155
1156         len = pb->buf_buf + pb->buf_size - pb->buf_get;
1157         if (count > len) {
1158                 memcpy(buf, pb->buf_get, len);
1159                 memcpy(buf+len, pb->buf_buf, count - len);
1160                 pb->buf_get = pb->buf_buf + count - len;
1161         } else {
1162                 memcpy(buf, pb->buf_get, count);
1163                 if (count < len)
1164                         pb->buf_get += count;
1165                 else /* count == len */
1166                         pb->buf_get = pb->buf_buf;
1167         }
1168
1169         return count;
1170
1171 }
1172
1173 static int __init pl2303_init (void)
1174 {
1175         int retval;
1176         retval = usb_serial_register(&pl2303_device);
1177         if (retval)
1178                 goto failed_usb_serial_register;
1179         retval = usb_register(&pl2303_driver);
1180         if (retval)
1181                 goto failed_usb_register;
1182         info(DRIVER_DESC);
1183         return 0;
1184 failed_usb_register:
1185         usb_serial_deregister(&pl2303_device);
1186 failed_usb_serial_register:
1187         return retval;
1188 }
1189
1190
1191 static void __exit pl2303_exit (void)
1192 {
1193         usb_deregister (&pl2303_driver);
1194         usb_serial_deregister (&pl2303_device);
1195 }
1196
1197
1198 module_init(pl2303_init);
1199 module_exit(pl2303_exit);
1200
1201 MODULE_DESCRIPTION(DRIVER_DESC);
1202 MODULE_LICENSE("GPL");
1203
1204 module_param(debug, bool, S_IRUGO | S_IWUSR);
1205 MODULE_PARM_DESC(debug, "Debug enabled or not");
1206