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

   1 /*
   2  * USB Empeg empeg-car player driver
   3  *
   4  *      Copyright (C) 2000, 2001
   5  *          Gary Brubaker (xavyer@ix.netcom.com)
   6  *
   7  *      Copyright (C) 1999 - 2001
   8  *          Greg Kroah-Hartman (greg@kroah.com)
   9  *
  10  *      This program is free software; you can redistribute it and/or modify
  11  *      it under the terms of the GNU General Public License, as published by
  12  *      the Free Software Foundation, version 2.
  13  *
  14  * See Documentation/usb/usb-serial.txt for more information on using this driver
  15  *
  16  * (07/16/2001) gb
  17  *      remove unused code in empeg_close() (thanks to Oliver Neukum for pointing this
  18  *      out) and rewrote empeg_set_termios().
  19  *
  20  * (05/30/2001) gkh
  21  *      switched from using spinlock to a semaphore, which fixes lots of problems.
  22  *
  23  * (04/08/2001) gb
  24  *      Identify version on module load.
  25  *
  26  * (01/22/2001) gb
  27  *      Added write_room() and chars_in_buffer() support.
  28  *
  29  * (12/21/2000) gb
  30  *      Moved termio stuff inside the port->active check.
  31  *      Moved MOD_DEC_USE_COUNT to end of empeg_close().
  32  *
  33  * (12/03/2000) gb
  34  *      Added port->tty->ldisc.set_termios(port->tty, NULL) to empeg_open()
  35  *      This notifies the tty driver that the termios have changed.
  36  *
  37  * (11/13/2000) gb
  38  *      Moved tty->low_latency = 1 from empeg_read_bulk_callback() to empeg_open()
  39  *      (It only needs to be set once - Doh!)
  40  *
  41  * (11/11/2000) gb
  42  *      Updated to work with id_table structure.
  43  *
  44  * (11/04/2000) gb
  45  *      Forked this from visor.c, and hacked it up to work with an
  46  *      Empeg ltd. empeg-car player.  Constructive criticism welcomed.
  47  *      I would like to say, 'Thank You' to Greg Kroah-Hartman for the
  48  *      use of his code, and for his guidance, advice and patience. :)
  49  *      A 'Thank You' is in order for John Ripley of Empeg ltd for his
  50  *      advice, and patience too.
  51  *
  52  */
  53
  54 #include <linux/config.h>
  55 #include <linux/kernel.h>
  56 #include <linux/errno.h>
  57 #include <linux/init.h>
  58 #include <linux/slab.h>
  59 #include <linux/tty.h>
  60 #include <linux/tty_driver.h>
  61 #include <linux/tty_flip.h>
  62 #include <linux/module.h>
  63 #include <linux/spinlock.h>
  64 #include <asm/uaccess.h>
  65 #include <linux/usb.h>
  66 #include "usb-serial.h"
  67
  68 static int debug;
  69
  70 /*
  71  * Version Information
  72  */
  73 #define DRIVER_VERSION "v1.2"
  74 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Gary Brubaker <xavyer@ix.netcom.com>"
  75 #define DRIVER_DESC "USB Empeg Mark I/II Driver"
  76
  77 #define EMPEG_VENDOR_ID                 0x084f
  78 #define EMPEG_PRODUCT_ID                0x0001
  79
  80 /* function prototypes for an empeg-car player */
  81 static int  empeg_open                  (struct usb_serial_port *port, struct file *filp);
  82 static void empeg_close                 (struct usb_serial_port *port, struct file *filp);
  83 static int  empeg_write                 (struct usb_serial_port *port,
  84                                         const unsigned char *buf,
  85                                         int count);
  86 static int  empeg_write_room            (struct usb_serial_port *port);
  87 static int  empeg_chars_in_buffer       (struct usb_serial_port *port);
  88 static void empeg_throttle              (struct usb_serial_port *port);
  89 static void empeg_unthrottle            (struct usb_serial_port *port);
  90 static int  empeg_startup               (struct usb_serial *serial);
  91 static void empeg_shutdown              (struct usb_serial *serial);
  92 static int  empeg_ioctl                 (struct usb_serial_port *port,
  93                                         struct file * file,
  94                                         unsigned int cmd,
  95                                         unsigned long arg);
  96 static void empeg_set_termios           (struct usb_serial_port *port, struct termios *old_termios);
  97 static void empeg_write_bulk_callback   (struct urb *urb, struct pt_regs *regs);
  98 static void empeg_read_bulk_callback    (struct urb *urb, struct pt_regs *regs);
  99
 100 static struct usb_device_id id_table [] = {
 101         { USB_DEVICE(EMPEG_VENDOR_ID, EMPEG_PRODUCT_ID) },
 102         { }                                     /* Terminating entry */
 103 };
 104
 105 MODULE_DEVICE_TABLE (usb, id_table);
 106
 107 static struct usb_driver empeg_driver = {
 108         .owner =        THIS_MODULE,
 109         .name =         "empeg",
 110         .probe =        usb_serial_probe,
 111         .disconnect =   usb_serial_disconnect,
 112         .id_table =     id_table,
 113         .no_dynamic_id =        1,
 114 };
 115
 116 static struct usb_serial_driver empeg_device = {
 117         .driver = {
 118                 .owner =        THIS_MODULE,
 119                 .name =         "empeg",
 120         },
 121         .id_table =             id_table,
 122         .num_interrupt_in =     0,
 123         .num_bulk_in =          1,
 124         .num_bulk_out =         1,
 125         .num_ports =            1,
 126         .open =                 empeg_open,
 127         .close =                empeg_close,
 128         .throttle =             empeg_throttle,
 129         .unthrottle =           empeg_unthrottle,
 130         .attach =               empeg_startup,
 131         .shutdown =             empeg_shutdown,
 132         .ioctl =                empeg_ioctl,
 133         .set_termios =          empeg_set_termios,
 134         .write =                empeg_write,
 135         .write_room =           empeg_write_room,
 136         .chars_in_buffer =      empeg_chars_in_buffer,
 137         .write_bulk_callback =  empeg_write_bulk_callback,
 138         .read_bulk_callback =   empeg_read_bulk_callback,
 139 };
 140
 141 #define NUM_URBS                        16
 142 #define URB_TRANSFER_BUFFER_SIZE        4096
 143
 144 static struct urb       *write_urb_pool[NUM_URBS];
 145 static spinlock_t       write_urb_pool_lock;
 146 static int              bytes_in;
 147 static int              bytes_out;
 148
 149 /******************************************************************************
 150  * Empeg specific driver functions
 151  ******************************************************************************/
 152 static int empeg_open (struct usb_serial_port *port, struct file *filp)
 153 {
 154         struct usb_serial *serial = port->serial;
 155         int result = 0;
 156
 157         dbg("%s - port %d", __FUNCTION__, port->number);
 158
 159         /* Force default termio settings */
 160         empeg_set_termios (port, NULL) ;
 161
 162         bytes_in = 0;
 163         bytes_out = 0;
 164
 165         /* Start reading from the device */
 166         usb_fill_bulk_urb(
 167                 port->read_urb,
 168                 serial->dev,
 169                 usb_rcvbulkpipe(serial->dev,
 170                         port->bulk_in_endpointAddress),
 171                 port->read_urb->transfer_buffer,
 172                 port->read_urb->transfer_buffer_length,
 173                 empeg_read_bulk_callback,
 174                 port);
 175
 176         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 177
 178         if (result)
 179                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 180
 181         return result;
 182 }
 183
 184
 185 static void empeg_close (struct usb_serial_port *port, struct file * filp)
 186 {
 187         dbg("%s - port %d", __FUNCTION__, port->number);
 188
 189         /* shutdown our bulk read */
 190         usb_kill_urb(port->read_urb);
 191         /* Uncomment the following line if you want to see some statistics in your syslog */
 192         /* dev_info (&port->dev, "Bytes In = %d  Bytes Out = %d\n", bytes_in, bytes_out); */
 193 }
 194
 195
 196 static int empeg_write (struct usb_serial_port *port, const unsigned char *buf, int count)
 197 {
 198         struct usb_serial *serial = port->serial;
 199         struct urb *urb;
 200         const unsigned char *current_position = buf;
 201         unsigned long flags;
 202         int status;
 203         int i;
 204         int bytes_sent = 0;
 205         int transfer_size;
 206
 207         dbg("%s - port %d", __FUNCTION__, port->number);
 208
 209         while (count > 0) {
 210
 211                 /* try to find a free urb in our list of them */
 212                 urb = NULL;
 213
 214                 spin_lock_irqsave (&write_urb_pool_lock, flags);
 215
 216                 for (i = 0; i < NUM_URBS; ++i) {
 217                         if (write_urb_pool[i]->status != -EINPROGRESS) {
 218                                 urb = write_urb_pool[i];
 219                                 break;
 220                         }
 221                 }
 222
 223                 spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 224
 225                 if (urb == NULL) {
 226                         dbg("%s - no more free urbs", __FUNCTION__);
 227                         goto exit;
 228                 }
 229
 230                 if (urb->transfer_buffer == NULL) {
 231                         urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
 232                         if (urb->transfer_buffer == NULL) {
 233                                 dev_err(&port->dev, "%s no more kernel memory...\n", __FUNCTION__);
 234                                 goto exit;
 235                         }
 236                 }
 237
 238                 transfer_size = min (count, URB_TRANSFER_BUFFER_SIZE);
 239
 240                 memcpy (urb->transfer_buffer, current_position, transfer_size);
 241
 242                 usb_serial_debug_data(debug, &port->dev, __FUNCTION__, transfer_size, urb->transfer_buffer);
 243
 244                 /* build up our urb */
 245                 usb_fill_bulk_urb (
 246                         urb,
 247                         serial->dev,
 248                         usb_sndbulkpipe(serial->dev,
 249                                 port->bulk_out_endpointAddress),
 250                         urb->transfer_buffer,
 251                         transfer_size,
 252                         empeg_write_bulk_callback,
 253                         port);
 254
 255                 /* send it down the pipe */
 256                 status = usb_submit_urb(urb, GFP_ATOMIC);
 257                 if (status) {
 258                         dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __FUNCTION__, status);
 259                         bytes_sent = status;
 260                         break;
 261                 }
 262
 263                 current_position += transfer_size;
 264                 bytes_sent += transfer_size;
 265                 count -= transfer_size;
 266                 bytes_out += transfer_size;
 267
 268         }
 269
 270 exit:
 271         return bytes_sent;
 272
 273 }
 274
 275
 276 static int empeg_write_room (struct usb_serial_port *port)
 277 {
 278         unsigned long flags;
 279         int i;
 280         int room = 0;
 281
 282         dbg("%s - port %d", __FUNCTION__, port->number);
 283
 284         spin_lock_irqsave (&write_urb_pool_lock, flags);
 285
 286         /* tally up the number of bytes available */
 287         for (i = 0; i < NUM_URBS; ++i) {
 288                 if (write_urb_pool[i]->status != -EINPROGRESS) {
 289                         room += URB_TRANSFER_BUFFER_SIZE;
 290                 }
 291         }
 292
 293         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 294
 295         dbg("%s - returns %d", __FUNCTION__, room);
 296
 297         return (room);
 298
 299 }
 300
 301
 302 static int empeg_chars_in_buffer (struct usb_serial_port *port)
 303 {
 304         unsigned long flags;
 305         int i;
 306         int chars = 0;
 307
 308         dbg("%s - port %d", __FUNCTION__, port->number);
 309
 310         spin_lock_irqsave (&write_urb_pool_lock, flags);
 311
 312         /* tally up the number of bytes waiting */
 313         for (i = 0; i < NUM_URBS; ++i) {
 314                 if (write_urb_pool[i]->status == -EINPROGRESS) {
 315                         chars += URB_TRANSFER_BUFFER_SIZE;
 316                 }
 317         }
 318
 319         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 320
 321         dbg("%s - returns %d", __FUNCTION__, chars);
 322
 323         return (chars);
 324
 325 }
 326
 327
 328 static void empeg_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 329 {
 330         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 331
 332         dbg("%s - port %d", __FUNCTION__, port->number);
 333
 334         if (urb->status) {
 335                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 336                 return;
 337         }
 338
 339         schedule_work(&port->work);
 340 }
 341
 342
 343 static void empeg_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 344 {
 345         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 346         struct tty_struct *tty;
 347         unsigned char *data = urb->transfer_buffer;
 348         int i;
 349         int result;
 350
 351         dbg("%s - port %d", __FUNCTION__, port->number);
 352
 353         if (urb->status) {
 354                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
 355                 return;
 356         }
 357
 358         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
 359
 360         tty = port->tty;
 361
 362         if (urb->actual_length) {
 363                 for (i = 0; i < urb->actual_length ; ++i) {
 364                         /* gb - 2000/11/13
 365                          * If we insert too many characters we'll overflow the buffer.
 366                          * This means we'll lose bytes - Decidedly bad.
 367                          */
 368                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
 369                                 tty_flip_buffer_push(tty);
 370                                 }
 371                         tty_insert_flip_char(tty, data[i], 0);
 372                 }
 373                 /* gb - 2000/11/13
 374                  * Goes straight through instead of scheduling - if tty->low_latency is set.
 375                  */
 376                 tty_flip_buffer_push(tty);
 377                 bytes_in += urb->actual_length;
 378         }
 379
 380         /* Continue trying to always read  */
 381         usb_fill_bulk_urb(
 382                 port->read_urb,
 383                 port->serial->dev,
 384                 usb_rcvbulkpipe(port->serial->dev,
 385                         port->bulk_in_endpointAddress),
 386                 port->read_urb->transfer_buffer,
 387                 port->read_urb->transfer_buffer_length,
 388                 empeg_read_bulk_callback,
 389                 port);
 390
 391         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 392
 393         if (result)
 394                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 395
 396         return;
 397
 398 }
 399
 400
 401 static void empeg_throttle (struct usb_serial_port *port)
 402 {
 403         dbg("%s - port %d", __FUNCTION__, port->number);
 404         usb_kill_urb(port->read_urb);
 405 }
 406
 407
 408 static void empeg_unthrottle (struct usb_serial_port *port)
 409 {
 410         int result;
 411
 412         dbg("%s - port %d", __FUNCTION__, port->number);
 413
 414         port->read_urb->dev = port->serial->dev;
 415
 416         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 417
 418         if (result)
 419                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 420
 421         return;
 422 }
 423
 424
 425 static int  empeg_startup (struct usb_serial *serial)
 426 {
 427         int r;
 428
 429         dbg("%s", __FUNCTION__);
 430
 431         if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
 432                 err("active config #%d != 1 ??",
 433                         serial->dev->actconfig->desc.bConfigurationValue);
 434                 return -ENODEV;
 435         }
 436         dbg("%s - reset config", __FUNCTION__);
 437         r = usb_reset_configuration (serial->dev);
 438
 439         /* continue on with initialization */
 440         return r;
 441
 442 }
 443
 444
 445 static void empeg_shutdown (struct usb_serial *serial)
 446 {
 447         dbg ("%s", __FUNCTION__);
 448 }
 449
 450
 451 static int empeg_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 452 {
 453         dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
 454
 455         return -ENOIOCTLCMD;
 456 }
 457
 458
 459 static void empeg_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 460 {
 461
 462         dbg("%s - port %d", __FUNCTION__, port->number);
 463
 464         if ((!port->tty) || (!port->tty->termios)) {
 465                 dbg("%s - no tty structures", __FUNCTION__);
 466                 return;
 467         }
 468
 469         /*
 470          * The empeg-car player wants these particular tty settings.
 471          * You could, for example, change the baud rate, however the
 472          * player only supports 115200 (currently), so there is really
 473          * no point in support for changes to the tty settings.
 474          * (at least for now)
 475          *
 476          * The default requirements for this device are:
 477          */
 478         port->tty->termios->c_iflag
 479                 &= ~(IGNBRK     /* disable ignore break */
 480                 | BRKINT        /* disable break causes interrupt */
 481                 | PARMRK        /* disable mark parity errors */
 482                 | ISTRIP        /* disable clear high bit of input characters */
 483                 | INLCR         /* disable translate NL to CR */
 484                 | IGNCR         /* disable ignore CR */
 485                 | ICRNL         /* disable translate CR to NL */
 486                 | IXON);        /* disable enable XON/XOFF flow control */
 487
 488         port->tty->termios->c_oflag
 489                 &= ~OPOST;      /* disable postprocess output characters */
 490
 491         port->tty->termios->c_lflag
 492                 &= ~(ECHO       /* disable echo input characters */
 493                 | ECHONL        /* disable echo new line */
 494                 | ICANON        /* disable erase, kill, werase, and rprnt special characters */
 495                 | ISIG          /* disable interrupt, quit, and suspend special characters */
 496                 | IEXTEN);      /* disable non-POSIX special characters */
 497
 498         port->tty->termios->c_cflag
 499                 &= ~(CSIZE      /* no size */
 500                 | PARENB        /* disable parity bit */
 501                 | CBAUD);       /* clear current baud rate */
 502
 503         port->tty->termios->c_cflag
 504                 |= (CS8         /* character size 8 bits */
 505                 | B115200);     /* baud rate 115200 */
 506
 507         /*
 508          * Force low_latency on; otherwise the pushes are scheduled;
 509          * this is bad as it opens up the possibility of dropping bytes
 510          * on the floor.  We don't want to drop bytes on the floor. :)
 511          */
 512         port->tty->low_latency = 1;
 513
 514         return;
 515 }
 516
 517
 518 static int __init empeg_init (void)
 519 {
 520         struct urb *urb;
 521         int i, retval;
 522
 523         /* create our write urb pool and transfer buffers */
 524         spin_lock_init (&write_urb_pool_lock);
 525         for (i = 0; i < NUM_URBS; ++i) {
 526                 urb = usb_alloc_urb(0, GFP_KERNEL);
 527                 write_urb_pool[i] = urb;
 528                 if (urb == NULL) {
 529                         err("No more urbs???");
 530                         continue;
 531                 }
 532
 533                 urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
 534                 if (!urb->transfer_buffer) {
 535                         err("%s - out of memory for urb buffers.",
 536                             __FUNCTION__);
 537                         continue;
 538                 }
 539         }
 540
 541         retval = usb_serial_register(&empeg_device);
 542         if (retval)
 543                 goto failed_usb_serial_register;
 544         retval = usb_register(&empeg_driver);
 545         if (retval)
 546                 goto failed_usb_register;
 547
 548         info(DRIVER_VERSION ":" DRIVER_DESC);
 549
 550         return 0;
 551 failed_usb_register:
 552         usb_serial_deregister(&empeg_device);
 553 failed_usb_serial_register:
 554         for (i = 0; i < NUM_URBS; ++i) {
 555                 if (write_urb_pool[i]) {
 556                         kfree(write_urb_pool[i]->transfer_buffer);
 557                         usb_free_urb(write_urb_pool[i]);
 558                 }
 559         }
 560         return retval;
 561 }
 562
 563
 564 static void __exit empeg_exit (void)
 565 {
 566         int i;
 567         unsigned long flags;
 568
 569         usb_deregister(&empeg_driver);
 570         usb_serial_deregister (&empeg_device);
 571
 572         spin_lock_irqsave (&write_urb_pool_lock, flags);
 573
 574         for (i = 0; i < NUM_URBS; ++i) {
 575                 if (write_urb_pool[i]) {
 576                         /* FIXME - uncomment the following usb_kill_urb call when
 577                          * the host controllers get fixed to set urb->dev = NULL after
 578                          * the urb is finished.  Otherwise this call oopses. */
 579                         /* usb_kill_urb(write_urb_pool[i]); */
 580                         kfree(write_urb_pool[i]->transfer_buffer);
 581                         usb_free_urb (write_urb_pool[i]);
 582                 }
 583         }
 584
 585         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 586 }
 587
 588
 589 module_init(empeg_init);
 590 module_exit(empeg_exit);
 591
 592 MODULE_AUTHOR( DRIVER_AUTHOR );
 593 MODULE_DESCRIPTION( DRIVER_DESC );
 594 MODULE_LICENSE("GPL");
 595
 596 module_param(debug, bool, S_IRUGO | S_IWUSR);
 597 MODULE_PARM_DESC(debug, "Debug enabled or not");