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