drivers/usb/serial/cp2101.c

   1 /*
   2  * Silicon Laboratories CP2101/CP2102 USB to RS232 serial adaptor driver
   3  *
   4  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
   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
   8  *      2 as published by the Free Software Foundation.
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/kernel.h>
  14 #include <linux/errno.h>
  15 #include <linux/slab.h>
  16 #include <linux/tty.h>
  17 #include <linux/tty_flip.h>
  18 #include <linux/module.h>
  19 #include <linux/moduleparam.h>
  20 #include <linux/usb.h>
  21 #include <asm/uaccess.h>
  22 #include "usb-serial.h"
  23
  24 /*
  25  * Version Information
  26  */
  27 #define DRIVER_VERSION "v0.03"
  28 #define DRIVER_DESC "Silicon Labs CP2101/CP2102 RS232 serial adaptor driver"
  29
  30 /*
  31  * Function Prototypes
  32  */
  33 static int cp2101_open(struct usb_serial_port*, struct file*);
  34 static void cp2101_cleanup(struct usb_serial_port*);
  35 static void cp2101_close(struct usb_serial_port*, struct file*);
  36 static void cp2101_get_termios(struct usb_serial_port*);
  37 static void cp2101_set_termios(struct usb_serial_port*, struct termios*);
  38 static void cp2101_break_ctl(struct usb_serial_port*, int);
  39 static int cp2101_startup (struct usb_serial *);
  40 static void cp2101_shutdown(struct usb_serial*);
  41
  42
  43 static int debug;
  44
  45 static struct usb_device_id id_table [] = {
  46         {USB_DEVICE(0x10c4, 0xea60) },  /*Silicon labs factory default*/
  47         {USB_DEVICE(0x10ab, 0x10c5) },  /*Siemens MC60 Cable*/
  48         { } /* Terminating Entry*/
  49 };
  50
  51 MODULE_DEVICE_TABLE (usb, id_table);
  52
  53 static struct usb_driver cp2101_driver = {
  54         .owner          = THIS_MODULE,
  55         .name           = "CP2101",
  56         .probe          = usb_serial_probe,
  57         .disconnect     = usb_serial_disconnect,
  58         .id_table       = id_table,
  59 };
  60
  61 static struct usb_serial_device_type cp2101_device = {
  62         .owner                  = THIS_MODULE,
  63         .name                   = "CP2101",
  64         .id_table               = id_table,
  65         .num_interrupt_in       = 0,
  66         .num_bulk_in            = 0,
  67         .num_bulk_out           = 0,
  68         .num_ports              = 1,
  69         .open                   = cp2101_open,
  70         .close                  = cp2101_close,
  71         .break_ctl              = cp2101_break_ctl,
  72         .set_termios            = cp2101_set_termios,
  73         .attach                 = cp2101_startup,
  74         .shutdown               = cp2101_shutdown,
  75 };
  76
  77 /*Config request types*/
  78 #define REQTYPE_HOST_TO_DEVICE  0x41
  79 #define REQTYPE_DEVICE_TO_HOST  0xc1
  80
  81 /*Config SET requests. To GET, add 1 to the request number*/
  82 #define CP2101_UART             0x00    /*Enable / Disable*/
  83 #define CP2101_BAUDRATE         0x01    /*(BAUD_RATE_GEN_FREQ / baudrate)*/
  84 #define CP2101_BITS             0x03    /*0x(0)(data bits)(parity)(stop bits)*/
  85 #define CP2101_BREAK            0x05    /*On / Off*/
  86 #define CP2101_DTRRTS           0x07    /*101 / 202  ???*/
  87 #define CP2101_CONFIG_16        0x13    /*16 bytes of config data ???*/
  88 #define CP2101_CONFIG_6         0x19    /*6 bytes of config data ???*/
  89
  90 /*CP2101_UART*/
  91 #define UART_ENABLE             0x0001
  92 #define UART_DISABLE            0x0000
  93
  94 /*CP2101_BAUDRATE*/
  95 #define BAUD_RATE_GEN_FREQ      0x384000
  96
  97 /*CP2101_BITS*/
  98 #define BITS_DATA_MASK          0X0f00
  99 #define BITS_DATA_6             0X0600
 100 #define BITS_DATA_7             0X0700
 101 #define BITS_DATA_8             0X0800
 102 #define BITS_DATA_9             0X0900
 103
 104 #define BITS_PARITY_MASK        0x00f0
 105 #define BITS_PARITY_NONE        0x0000
 106 #define BITS_PARITY_ODD         0x0010
 107 #define BITS_PARITY_EVEN        0x0020
 108 #define BITS_PARITY_MARK        0x0030
 109 #define BITS_PARITY_SPACE       0x0040
 110
 111 #define BITS_STOP_MASK          0x000f
 112 #define BITS_STOP_1             0x0000
 113 #define BITS_STOP_1_5           0x0001
 114 #define BITS_STOP_2             0x0002
 115 #define BREAK_ON                0x0000
 116 #define BREAK_OFF               0x0001
 117
 118
 119 static int cp2101_get_config(struct usb_serial_port* port, u8 request)
 120 {
 121         struct usb_serial *serial = port->serial;
 122         unsigned char buf[4];
 123         unsigned int value;
 124         int result, i;
 125
 126         /*For get requests, the request number must be incremented*/
 127         request++;
 128
 129         /*Issue the request, attempting to read 4 bytes*/
 130         result = usb_control_msg (serial->dev,usb_rcvctrlpipe (serial->dev, 0),
 131                                 request, REQTYPE_DEVICE_TO_HOST, 0x0000,
 132                                 0, buf, 4, 300);
 133
 134         if (result < 0) {
 135                 dev_err(&port->dev, "%s - Unable to send config request, "
 136                                 "request=0x%x result=%d\n",
 137                                 __FUNCTION__, request, result);
 138                 return result;
 139         }
 140
 141         /*Assemble each byte read into an integer value*/
 142         value = 0;
 143         for (i=0; i<4 && i<result; i++)
 144                 value |= (buf[i] << (i * 8));
 145
 146         dbg( " %s - request=0x%x result=%d value=0x%x",
 147                         __FUNCTION__, request, result, value);
 148
 149         return value;
 150 }
 151
 152 static int cp2101_set_config(struct usb_serial_port* port, u8 request, u16 value)
 153 {
 154         struct usb_serial *serial = port->serial;
 155         int result;
 156         result = usb_control_msg (serial->dev, usb_sndctrlpipe(serial->dev, 0),
 157                         request, REQTYPE_HOST_TO_DEVICE, value,
 158                         0, NULL, 0, 300);
 159
 160         if (result <0) {
 161                 dev_err(&port->dev, "%s - Unable to send config request, "
 162                                 "request=0x%x value=0x%x result=%d\n",
 163                                 __FUNCTION__, request, value, result);
 164                 return result;
 165         }
 166
 167         dbg(" %s - request=0x%x value=0x%x result=%d",
 168                         __FUNCTION__, request, value, result);
 169
 170         return 0;
 171 }
 172
 173 static int cp2101_open (struct usb_serial_port *port, struct file *filp)
 174 {
 175         struct usb_serial *serial = port->serial;
 176         int result;
 177
 178         dbg("%s - port %d", __FUNCTION__, port->number);
 179
 180         if (cp2101_set_config(port, CP2101_UART, UART_ENABLE)) {
 181                 dev_err(&port->dev, "%s - Unable to enable UART\n",
 182                                 __FUNCTION__);
 183                 return -EPROTO;
 184         }
 185
 186         /* Start reading from the device */
 187         usb_fill_bulk_urb (port->read_urb, serial->dev,
 188                         usb_rcvbulkpipe(serial->dev,
 189                         port->bulk_in_endpointAddress),
 190                         port->read_urb->transfer_buffer,
 191                         port->read_urb->transfer_buffer_length,
 192                         serial->type->read_bulk_callback,
 193                         port);
 194         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 195         if (result) {
 196                 dev_err(&port->dev, "%s - failed resubmitting read urb, "
 197                                 "error %d\n", __FUNCTION__, result);
 198                 return result;
 199         }
 200
 201         /*Configure the termios structure*/
 202         cp2101_get_termios(port);
 203
 204         return 0;
 205 }
 206
 207 static void cp2101_cleanup (struct usb_serial_port *port)
 208 {
 209         struct usb_serial *serial = port->serial;
 210
 211         dbg("%s - port %d", __FUNCTION__, port->number);
 212
 213         if (serial->dev) {
 214                 /* shutdown any bulk reads that might be going on */
 215                 if (serial->num_bulk_out)
 216                         usb_kill_urb(port->write_urb);
 217                 if (serial->num_bulk_in)
 218                         usb_kill_urb(port->read_urb);
 219         }
 220 }
 221
 222 static void cp2101_close (struct usb_serial_port *port, struct file * filp)
 223 {
 224         dbg("%s - port %d", __FUNCTION__, port->number);
 225
 226         /* shutdown our urbs */
 227         dbg("%s - shutting down urbs", __FUNCTION__);
 228         usb_kill_urb(port->write_urb);
 229         usb_kill_urb(port->read_urb);
 230
 231         cp2101_set_config(port, CP2101_UART, UART_DISABLE);
 232 }
 233
 234 /* cp2101_get_termios*/
 235 /* Reads the baud rate, data bits, parity and stop bits from the device*/
 236 /* Corrects any unsupported values*/
 237 /* Configures the termios structure to reflect the state of the device*/
 238 static void cp2101_get_termios (struct usb_serial_port *port)
 239 {
 240         unsigned int cflag;
 241         int baud;
 242         int bits;
 243
 244         dbg("%s - port %d", __FUNCTION__, port->number);
 245
 246         if ((!port->tty) || (!port->tty->termios)) {
 247                 dbg("%s - no tty structures", __FUNCTION__);
 248                 return;
 249         }
 250         cflag = port->tty->termios->c_cflag;
 251
 252         baud = cp2101_get_config(port, CP2101_BAUDRATE);
 253         /*Convert to baudrate*/
 254         if (baud)
 255                 baud = BAUD_RATE_GEN_FREQ / baud;
 256
 257         dbg("%s - baud rate = %d", __FUNCTION__, baud);
 258         cflag &= ~CBAUD;
 259         switch (baud) {
 260                 /* The baud rates which are commented out below
 261                  * appear to be supported by the device
 262                  * but are non-standard
 263                  */
 264                 case 600:       cflag |= B600;          break;
 265                 case 1200:      cflag |= B1200;         break;
 266                 case 1800:      cflag |= B1800;         break;
 267                 case 2400:      cflag |= B2400;         break;
 268                 case 4800:      cflag |= B4800;         break;
 269                 /*case 7200:    cflag |= B7200;         break;*/
 270                 case 9600:      cflag |= B9600;         break;
 271                 /*case 14400:   cflag |= B14400;        break;*/
 272                 case 19200:     cflag |= B19200;        break;
 273                 /*case 28800:   cflag |= B28800;        break;*/
 274                 case 38400:     cflag |= B38400;        break;
 275                 /*case 55854:   cflag |= B55054;        break;*/
 276                 case 57600:     cflag |= B57600;        break;
 277                 case 115200:    cflag |= B115200;       break;
 278                 /*case 127117:  cflag |= B127117;       break;*/
 279                 case 230400:    cflag |= B230400;       break;
 280                 case 460800:    cflag |= B460800;       break;
 281                 case 921600:    cflag |= B921600;       break;
 282                 /*case 3686400: cflag |= B3686400;      break;*/
 283                 default:
 284                         dbg("%s - Baud rate is not supported, "
 285                                         "using 9600 baud", __FUNCTION__);
 286                         cflag |= B9600;
 287                         cp2101_set_config(port, CP2101_BAUDRATE,
 288                                         (BAUD_RATE_GEN_FREQ/9600));
 289                         break;
 290         }
 291
 292         bits = cp2101_get_config(port, CP2101_BITS);
 293         cflag &= ~CSIZE;
 294         switch(bits & BITS_DATA_MASK) {
 295                 case BITS_DATA_6:
 296                         dbg("%s - data bits = 6", __FUNCTION__);
 297                         cflag |= CS6;
 298                         break;
 299                 case BITS_DATA_7:
 300                         dbg("%s - data bits = 7", __FUNCTION__);
 301                         cflag |= CS7;
 302                         break;
 303                 case BITS_DATA_8:
 304                         dbg("%s - data bits = 8", __FUNCTION__);
 305                         cflag |= CS8;
 306                         break;
 307                 case BITS_DATA_9:
 308                         dbg("%s - data bits = 9 (not supported, "
 309                                         "using 8 data bits)", __FUNCTION__);
 310                         cflag |= CS8;
 311                         bits &= ~BITS_DATA_MASK;
 312                         bits |= BITS_DATA_8;
 313                         cp2101_set_config(port, CP2101_BITS, bits);
 314                         break;
 315                 default:
 316                         dbg("%s - Unknown number of data bits, "
 317                                         "using 8", __FUNCTION__);
 318                         cflag |= CS8;
 319                         bits &= ~BITS_DATA_MASK;
 320                         bits |= BITS_DATA_8;
 321                         cp2101_set_config(port, CP2101_BITS, bits);
 322                         break;
 323         }
 324
 325         switch(bits & BITS_PARITY_MASK) {
 326                 case BITS_PARITY_NONE:
 327                         dbg("%s - parity = NONE", __FUNCTION__);
 328                         cflag &= ~PARENB;
 329                         break;
 330                 case BITS_PARITY_ODD:
 331                         dbg("%s - parity = ODD", __FUNCTION__);
 332                         cflag |= (PARENB|PARODD);
 333                         break;
 334                 case BITS_PARITY_EVEN:
 335                         dbg("%s - parity = EVEN", __FUNCTION__);
 336                         cflag &= ~PARODD;
 337                         cflag |= PARENB;
 338                         break;
 339                 case BITS_PARITY_MARK:
 340                         dbg("%s - parity = MARK (not supported, "
 341                                         "disabling parity)", __FUNCTION__);
 342                         cflag &= ~PARENB;
 343                         bits &= ~BITS_PARITY_MASK;
 344                         cp2101_set_config(port, CP2101_BITS, bits);
 345                         break;
 346                 case BITS_PARITY_SPACE:
 347                         dbg("%s - parity = SPACE (not supported, "
 348                                         "disabling parity)", __FUNCTION__);
 349                         cflag &= ~PARENB;
 350                         bits &= ~BITS_PARITY_MASK;
 351                         cp2101_set_config(port, CP2101_BITS, bits);
 352                         break;
 353                 default:
 354                         dbg("%s - Unknown parity mode, "
 355                                         "disabling parity", __FUNCTION__);
 356                         cflag &= ~PARENB;
 357                         bits &= ~BITS_PARITY_MASK;
 358                         cp2101_set_config(port, CP2101_BITS, bits);
 359                         break;
 360         }
 361
 362         cflag &= ~CSTOPB;
 363         switch(bits & BITS_STOP_MASK) {
 364                 case BITS_STOP_1:
 365                         dbg("%s - stop bits = 1", __FUNCTION__);
 366                         break;
 367                 case BITS_STOP_1_5:
 368                         dbg("%s - stop bits = 1.5 (not supported, "
 369                                         "using 1 stop bit", __FUNCTION__);
 370                         bits &= ~BITS_STOP_MASK;
 371                         cp2101_set_config(port, CP2101_BITS, bits);
 372                         break;
 373                 case BITS_STOP_2:
 374                         dbg("%s - stop bits = 2", __FUNCTION__);
 375                         cflag |= CSTOPB;
 376                         break;
 377                 default:
 378                         dbg("%s - Unknown number of stop bits, "
 379                                         "using 1 stop bit", __FUNCTION__);
 380                         bits &= ~BITS_STOP_MASK;
 381                         cp2101_set_config(port, CP2101_BITS, bits);
 382                         break;
 383         }
 384
 385         port->tty->termios->c_cflag = cflag;
 386 }
 387
 388 static void cp2101_set_termios (struct usb_serial_port *port,
 389                 struct termios *old_termios)
 390 {
 391         unsigned int cflag, old_cflag=0;
 392         int baud=0;
 393         int bits;
 394
 395         dbg("%s - port %d", __FUNCTION__, port->number);
 396
 397         if ((!port->tty) || (!port->tty->termios)) {
 398                 dbg("%s - no tty structures", __FUNCTION__);
 399                 return;
 400         }
 401         cflag = port->tty->termios->c_cflag;
 402
 403         /* check that they really want us to change something */
 404         if (old_termios) {
 405                 if ((cflag == old_termios->c_cflag) &&
 406                                 (RELEVANT_IFLAG(port->tty->termios->c_iflag)
 407                                 == RELEVANT_IFLAG(old_termios->c_iflag))) {
 408                         dbg("%s - nothing to change...", __FUNCTION__);
 409                         return;
 410                 }
 411
 412                 old_cflag = old_termios->c_cflag;
 413         }
 414
 415         /* If the baud rate is to be updated*/
 416         if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
 417                 switch (cflag & CBAUD) {
 418                         /* The baud rates which are commented out below
 419                          * appear to be supported by the device
 420                          * but are non-standard
 421                          */
 422                         case B0:        baud = 0;       break;
 423                         case B600:      baud = 600;     break;
 424                         case B1200:     baud = 1200;    break;
 425                         case B1800:     baud = 1800;    break;
 426                         case B2400:     baud = 2400;    break;
 427                         case B4800:     baud = 4800;    break;
 428                         /*case B7200:   baud = 7200;    break;*/
 429                         case B9600:     baud = 9600;    break;
 430                         /*ase B14400:   baud = 14400;   break;*/
 431                         case B19200:    baud = 19200;   break;
 432                         /*case B28800:  baud = 28800;   break;*/
 433                         case B38400:    baud = 38400;   break;
 434                         /*case B55854:  baud = 55054;   break;*/
 435                         case B57600:    baud = 57600;   break;
 436                         case B115200:   baud = 115200;  break;
 437                         /*case B127117: baud = 127117;  break;*/
 438                         case B230400:   baud = 230400;  break;
 439                         case B460800:   baud = 460800;  break;
 440                         case B921600:   baud = 921600;  break;
 441                         /*case B3686400:        baud = 3686400; break;*/
 442                         default:
 443                                 dev_err(&port->dev, "cp2101 driver does not "
 444                                         "support the baudrate requested\n");
 445                                 break;
 446                 }
 447
 448                 if (baud) {
 449                         dbg("%s - Setting baud rate to %d baud", __FUNCTION__,
 450                                         baud);
 451                         if (cp2101_set_config(port, CP2101_BAUDRATE,
 452                                                 (BAUD_RATE_GEN_FREQ / baud)))
 453                                 dev_err(&port->dev, "Baud rate requested not "
 454                                                 "supported by device\n");
 455                 }
 456         }
 457
 458         /*If the number of data bits is to be updated*/
 459         if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
 460                 bits = cp2101_get_config(port, CP2101_BITS);
 461                 bits &= ~BITS_DATA_MASK;
 462                 switch (cflag & CSIZE) {
 463                         case CS6:
 464                                 bits |= BITS_DATA_6;
 465                                 dbg("%s - data bits = 6", __FUNCTION__);
 466                                 break;
 467                         case CS7:
 468                                 bits |= BITS_DATA_7;
 469                                 dbg("%s - data bits = 7", __FUNCTION__);
 470                                 break;
 471                         case CS8:
 472                                 bits |= BITS_DATA_8;
 473                                 dbg("%s - data bits = 8", __FUNCTION__);
 474                                 break;
 475                         /*case CS9:
 476                                 bits |= BITS_DATA_9;
 477                                 dbg("%s - data bits = 9", __FUNCTION__);
 478                                 break;*/
 479                         default:
 480                                 dev_err(&port->dev, "cp2101 driver does not "
 481                                         "support the number of bits requested,"
 482                                         " using 8 bit mode\n");
 483                                 bits |= BITS_DATA_8;
 484                                 break;
 485                 }
 486                 if (cp2101_set_config(port, CP2101_BITS, bits))
 487                         dev_err(&port->dev, "Number of data bits requested "
 488                                         "not supported by device\n");
 489         }
 490
 491         if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
 492                 bits = cp2101_get_config(port, CP2101_BITS);
 493                 bits &= ~BITS_PARITY_MASK;
 494                 if (cflag & PARENB) {
 495                         if (cflag & PARODD) {
 496                                 bits |= BITS_PARITY_ODD;
 497                                 dbg("%s - parity = ODD", __FUNCTION__);
 498                         } else {
 499                                 bits |= BITS_PARITY_EVEN;
 500                                 dbg("%s - parity = EVEN", __FUNCTION__);
 501                         }
 502                 }
 503                 if (cp2101_set_config(port, CP2101_BITS, bits))
 504                         dev_err(&port->dev, "Parity mode not supported "
 505                                         "by device\n");
 506         }
 507
 508         if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
 509                 bits = cp2101_get_config(port, CP2101_BITS);
 510                 bits &= ~BITS_STOP_MASK;
 511                 if (cflag & CSTOPB) {
 512                         bits |= BITS_STOP_2;
 513                         dbg("%s - stop bits = 2", __FUNCTION__);
 514                 } else {
 515                         bits |= BITS_STOP_1;
 516                         dbg("%s - stop bits = 1", __FUNCTION__);
 517                 }
 518                 if (cp2101_set_config(port, CP2101_BITS, bits))
 519                         dev_err(&port->dev, "Number of stop bits requested "
 520                                         "not supported by device\n");
 521         }
 522 }
 523
 524 static void cp2101_break_ctl (struct usb_serial_port *port, int break_state)
 525 {
 526         u16 state;
 527
 528         dbg("%s - port %d", __FUNCTION__, port->number);
 529         if (break_state == 0)
 530                 state = BREAK_OFF;
 531         else
 532                 state = BREAK_ON;
 533         dbg("%s - turning break %s", __FUNCTION__,
 534                         state==BREAK_OFF ? "off" : "on");
 535         cp2101_set_config(port, CP2101_BREAK, state);
 536 }
 537
 538 static int cp2101_startup (struct usb_serial *serial)
 539 {
 540         /*CP2101 buffers behave strangely unless device is reset*/
 541         usb_reset_device(serial->dev);
 542         return 0;
 543 }
 544
 545 static void cp2101_shutdown (struct usb_serial *serial)
 546 {
 547         int i;
 548
 549         dbg("%s", __FUNCTION__);
 550
 551         /* stop reads and writes on all ports */
 552         for (i=0; i < serial->num_ports; ++i) {
 553                 cp2101_cleanup(serial->port[i]);
 554         }
 555 }
 556
 557 static int __init cp2101_init (void)
 558 {
 559         int retval;
 560
 561         retval = usb_serial_register(&cp2101_device);
 562         if (retval)
 563                 return retval; /*Failed to register*/
 564
 565         retval = usb_register(&cp2101_driver);
 566         if (retval) {
 567                 /*Failed to register*/
 568                 usb_serial_deregister(&cp2101_device);
 569                 return retval;
 570         }
 571
 572         /*Success*/
 573         info(DRIVER_DESC " " DRIVER_VERSION);
 574         return 0;
 575 }
 576
 577 static void __exit cp2101_exit (void)
 578 {
 579         usb_deregister (&cp2101_driver);
 580         usb_serial_deregister (&cp2101_device);
 581 }
 582
 583 module_init(cp2101_init);
 584 module_exit(cp2101_exit);
 585
 586 MODULE_DESCRIPTION(DRIVER_DESC);
 587 MODULE_VERSION(DRIVER_VERSION);
 588 MODULE_LICENSE("GPL");
 589
 590 module_param(debug, bool, S_IRUGO | S_IWUSR);
 591 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");