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 };
 114
 115 static struct usb_serial_device_type empeg_device = {
 116         .owner =                THIS_MODULE,
 117         .name =                 "Empeg",
 118         .id_table =             id_table,
 119         .num_interrupt_in =     0,
 120         .num_bulk_in =          1,
 121         .num_bulk_out =         1,
 122         .num_ports =            1,
 123         .open =                 empeg_open,
 124         .close =                empeg_close,
 125         .throttle =             empeg_throttle,
 126         .unthrottle =           empeg_unthrottle,
 127         .attach =               empeg_startup,
 128         .shutdown =             empeg_shutdown,
 129         .ioctl =                empeg_ioctl,
 130         .set_termios =          empeg_set_termios,
 131         .write =                empeg_write,
 132         .write_room =           empeg_write_room,
 133         .chars_in_buffer =      empeg_chars_in_buffer,
 134         .write_bulk_callback =  empeg_write_bulk_callback,
 135         .read_bulk_callback =   empeg_read_bulk_callback,
 136 };
 137
 138 #define NUM_URBS                        16
 139 #define URB_TRANSFER_BUFFER_SIZE        4096
 140
 141 static struct urb       *write_urb_pool[NUM_URBS];
 142 static spinlock_t       write_urb_pool_lock;
 143 static int              bytes_in;
 144 static int              bytes_out;
 145
 146 /******************************************************************************
 147  * Empeg specific driver functions
 148  ******************************************************************************/
 149 static int empeg_open (struct usb_serial_port *port, struct file *filp)
 150 {
 151         struct usb_serial *serial = port->serial;
 152         int result = 0;
 153
 154         dbg("%s - port %d", __FUNCTION__, port->number);
 155
 156         /* Force default termio settings */
 157         empeg_set_termios (port, NULL) ;
 158
 159         bytes_in = 0;
 160         bytes_out = 0;
 161
 162         /* Start reading from the device */
 163         usb_fill_bulk_urb(
 164                 port->read_urb,
 165                 serial->dev,
 166                 usb_rcvbulkpipe(serial->dev,
 167                         port->bulk_in_endpointAddress),
 168                 port->read_urb->transfer_buffer,
 169                 port->read_urb->transfer_buffer_length,
 170                 empeg_read_bulk_callback,
 171                 port);
 172
 173         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 174
 175         if (result)
 176                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 177
 178         return result;
 179 }
 180
 181
 182 static void empeg_close (struct usb_serial_port *port, struct file * filp)
 183 {
 184         dbg("%s - port %d", __FUNCTION__, port->number);
 185
 186         /* shutdown our bulk read */
 187         usb_kill_urb(port->read_urb);
 188         /* Uncomment the following line if you want to see some statistics in your syslog */
 189         /* dev_info (&port->dev, "Bytes In = %d  Bytes Out = %d\n", bytes_in, bytes_out); */
 190 }
 191
 192
 193 static int empeg_write (struct usb_serial_port *port, const unsigned char *buf, int count)
 194 {
 195         struct usb_serial *serial = port->serial;
 196         struct urb *urb;
 197         const unsigned char *current_position = buf;
 198         unsigned long flags;
 199         int status;
 200         int i;
 201         int bytes_sent = 0;
 202         int transfer_size;
 203
 204         dbg("%s - port %d", __FUNCTION__, port->number);
 205
 206         while (count > 0) {
 207
 208                 /* try to find a free urb in our list of them */
 209                 urb = NULL;
 210
 211                 spin_lock_irqsave (&write_urb_pool_lock, flags);
 212
 213                 for (i = 0; i < NUM_URBS; ++i) {
 214                         if (write_urb_pool[i]->status != -EINPROGRESS) {
 215                                 urb = write_urb_pool[i];
 216                                 break;
 217                         }
 218                 }
 219
 220                 spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 221
 222                 if (urb == NULL) {
 223                         dbg("%s - no more free urbs", __FUNCTION__);
 224                         goto exit;
 225                 }
 226
 227                 if (urb->transfer_buffer == NULL) {
 228                         urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
 229                         if (urb->transfer_buffer == NULL) {
 230                                 dev_err(&port->dev, "%s no more kernel memory...\n", __FUNCTION__);
 231                                 goto exit;
 232                         }
 233                 }
 234
 235                 transfer_size = min (count, URB_TRANSFER_BUFFER_SIZE);
 236
 237                 memcpy (urb->transfer_buffer, current_position, transfer_size);
 238
 239                 usb_serial_debug_data(debug, &port->dev, __FUNCTION__, transfer_size, urb->transfer_buffer);
 240
 241                 /* build up our urb */
 242                 usb_fill_bulk_urb (
 243                         urb,
 244                         serial->dev,
 245                         usb_sndbulkpipe(serial->dev,
 246                                 port->bulk_out_endpointAddress),
 247                         urb->transfer_buffer,
 248                         transfer_size,
 249                         empeg_write_bulk_callback,
 250                         port);
 251
 252                 /* send it down the pipe */
 253                 status = usb_submit_urb(urb, GFP_ATOMIC);
 254                 if (status) {
 255                         dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __FUNCTION__, status);
 256                         bytes_sent = status;
 257                         break;
 258                 }
 259
 260                 current_position += transfer_size;
 261                 bytes_sent += transfer_size;
 262                 count -= transfer_size;
 263                 bytes_out += transfer_size;
 264
 265         }
 266
 267 exit:
 268         return bytes_sent;
 269
 270 }
 271
 272
 273 static int empeg_write_room (struct usb_serial_port *port)
 274 {
 275         unsigned long flags;
 276         int i;
 277         int room = 0;
 278
 279         dbg("%s - port %d", __FUNCTION__, port->number);
 280
 281         spin_lock_irqsave (&write_urb_pool_lock, flags);
 282
 283         /* tally up the number of bytes available */
 284         for (i = 0; i < NUM_URBS; ++i) {
 285                 if (write_urb_pool[i]->status != -EINPROGRESS) {
 286                         room += URB_TRANSFER_BUFFER_SIZE;
 287                 }
 288         }
 289
 290         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 291
 292         dbg("%s - returns %d", __FUNCTION__, room);
 293
 294         return (room);
 295
 296 }
 297
 298
 299 static int empeg_chars_in_buffer (struct usb_serial_port *port)
 300 {
 301         unsigned long flags;
 302         int i;
 303         int chars = 0;
 304
 305         dbg("%s - port %d", __FUNCTION__, port->number);
 306
 307         spin_lock_irqsave (&write_urb_pool_lock, flags);
 308
 309         /* tally up the number of bytes waiting */
 310         for (i = 0; i < NUM_URBS; ++i) {
 311                 if (write_urb_pool[i]->status == -EINPROGRESS) {
 312                         chars += URB_TRANSFER_BUFFER_SIZE;
 313                 }
 314         }
 315
 316         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 317
 318         dbg("%s - returns %d", __FUNCTION__, chars);
 319
 320         return (chars);
 321
 322 }
 323
 324
 325 static void empeg_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 326 {
 327         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 328
 329         dbg("%s - port %d", __FUNCTION__, port->number);
 330
 331         if (urb->status) {
 332                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 333                 return;
 334         }
 335
 336         schedule_work(&port->work);
 337 }
 338
 339
 340 static void empeg_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 341 {
 342         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 343         struct tty_struct *tty;
 344         unsigned char *data = urb->transfer_buffer;
 345         int i;
 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                 for (i = 0; i < urb->actual_length ; ++i) {
 361                         /* gb - 2000/11/13
 362                          * If we insert too many characters we'll overflow the buffer.
 363                          * This means we'll lose bytes - Decidedly bad.
 364                          */
 365                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
 366                                 tty_flip_buffer_push(tty);
 367                                 }
 368                         tty_insert_flip_char(tty, data[i], 0);
 369                 }
 370                 /* gb - 2000/11/13
 371                  * Goes straight through instead of scheduling - if tty->low_latency is set.
 372                  */
 373                 tty_flip_buffer_push(tty);
 374                 bytes_in += urb->actual_length;
 375         }
 376
 377         /* Continue trying to always read  */
 378         usb_fill_bulk_urb(
 379                 port->read_urb,
 380                 port->serial->dev,
 381                 usb_rcvbulkpipe(port->serial->dev,
 382                         port->bulk_in_endpointAddress),
 383                 port->read_urb->transfer_buffer,
 384                 port->read_urb->transfer_buffer_length,
 385                 empeg_read_bulk_callback,
 386                 port);
 387
 388         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 389
 390         if (result)
 391                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 392
 393         return;
 394
 395 }
 396
 397
 398 static void empeg_throttle (struct usb_serial_port *port)
 399 {
 400         dbg("%s - port %d", __FUNCTION__, port->number);
 401         usb_kill_urb(port->read_urb);
 402 }
 403
 404
 405 static void empeg_unthrottle (struct usb_serial_port *port)
 406 {
 407         int result;
 408
 409         dbg("%s - port %d", __FUNCTION__, port->number);
 410
 411         port->read_urb->dev = port->serial->dev;
 412
 413         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 414
 415         if (result)
 416                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 417
 418         return;
 419 }
 420
 421
 422 static int  empeg_startup (struct usb_serial *serial)
 423 {
 424         int r;
 425
 426         dbg("%s", __FUNCTION__);
 427
 428         if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
 429                 err("active config #%d != 1 ??",
 430                         serial->dev->actconfig->desc.bConfigurationValue);
 431                 return -ENODEV;
 432         }
 433         dbg("%s - reset config", __FUNCTION__);
 434         r = usb_reset_configuration (serial->dev);
 435
 436         /* continue on with initialization */
 437         return r;
 438
 439 }
 440
 441
 442 static void empeg_shutdown (struct usb_serial *serial)
 443 {
 444         dbg ("%s", __FUNCTION__);
 445 }
 446
 447
 448 static int empeg_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 449 {
 450         dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
 451
 452         return -ENOIOCTLCMD;
 453 }
 454
 455
 456 static void empeg_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 457 {
 458
 459         dbg("%s - port %d", __FUNCTION__, port->number);
 460
 461         if ((!port->tty) || (!port->tty->termios)) {
 462                 dbg("%s - no tty structures", __FUNCTION__);
 463                 return;
 464         }
 465
 466         /*
 467          * The empeg-car player wants these particular tty settings.
 468          * You could, for example, change the baud rate, however the
 469          * player only supports 115200 (currently), so there is really
 470          * no point in support for changes to the tty settings.
 471          * (at least for now)
 472          *
 473          * The default requirements for this device are:
 474          */
 475         port->tty->termios->c_iflag
 476                 &= ~(IGNBRK     /* disable ignore break */
 477                 | BRKINT        /* disable break causes interrupt */
 478                 | PARMRK        /* disable mark parity errors */
 479                 | ISTRIP        /* disable clear high bit of input characters */
 480                 | INLCR         /* disable translate NL to CR */
 481                 | IGNCR         /* disable ignore CR */
 482                 | ICRNL         /* disable translate CR to NL */
 483                 | IXON);        /* disable enable XON/XOFF flow control */
 484
 485         port->tty->termios->c_oflag
 486                 &= ~OPOST;      /* disable postprocess output characters */
 487
 488         port->tty->termios->c_lflag
 489                 &= ~(ECHO       /* disable echo input characters */
 490                 | ECHONL        /* disable echo new line */
 491                 | ICANON        /* disable erase, kill, werase, and rprnt special characters */
 492                 | ISIG          /* disable interrupt, quit, and suspend special characters */
 493                 | IEXTEN);      /* disable non-POSIX special characters */
 494
 495         port->tty->termios->c_cflag
 496                 &= ~(CSIZE      /* no size */
 497                 | PARENB        /* disable parity bit */
 498                 | CBAUD);       /* clear current baud rate */
 499
 500         port->tty->termios->c_cflag
 501                 |= (CS8         /* character size 8 bits */
 502                 | B115200);     /* baud rate 115200 */
 503
 504         /*
 505          * Force low_latency on; otherwise the pushes are scheduled;
 506          * this is bad as it opens up the possibility of dropping bytes
 507          * on the floor.  We don't want to drop bytes on the floor. :)
 508          */
 509         port->tty->low_latency = 1;
 510
 511         return;
 512 }
 513
 514
 515 static int __init empeg_init (void)
 516 {
 517         struct urb *urb;
 518         int i, retval;
 519
 520         /* create our write urb pool and transfer buffers */
 521         spin_lock_init (&write_urb_pool_lock);
 522         for (i = 0; i < NUM_URBS; ++i) {
 523                 urb = usb_alloc_urb(0, GFP_KERNEL);
 524                 write_urb_pool[i] = urb;
 525                 if (urb == NULL) {
 526                         err("No more urbs???");
 527                         continue;
 528                 }
 529
 530                 urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
 531                 if (!urb->transfer_buffer) {
 532                         err("%s - out of memory for urb buffers.",
 533                             __FUNCTION__);
 534                         continue;
 535                 }
 536         }
 537
 538         retval = usb_serial_register(&empeg_device);
 539         if (retval)
 540                 goto failed_usb_serial_register;
 541         retval = usb_register(&empeg_driver);
 542         if (retval)
 543                 goto failed_usb_register;
 544
 545         info(DRIVER_VERSION ":" DRIVER_DESC);
 546
 547         return 0;
 548 failed_usb_register:
 549         usb_serial_deregister(&empeg_device);
 550 failed_usb_serial_register:
 551         for (i = 0; i < NUM_URBS; ++i) {
 552                 if (write_urb_pool[i]) {
 553                         kfree(write_urb_pool[i]->transfer_buffer);
 554                         usb_free_urb(write_urb_pool[i]);
 555                 }
 556         }
 557         return retval;
 558 }
 559
 560
 561 static void __exit empeg_exit (void)
 562 {
 563         int i;
 564         unsigned long flags;
 565
 566         usb_deregister(&empeg_driver);
 567         usb_serial_deregister (&empeg_device);
 568
 569         spin_lock_irqsave (&write_urb_pool_lock, flags);
 570
 571         for (i = 0; i < NUM_URBS; ++i) {
 572                 if (write_urb_pool[i]) {
 573                         /* FIXME - uncomment the following usb_kill_urb call when
 574                          * the host controllers get fixed to set urb->dev = NULL after
 575                          * the urb is finished.  Otherwise this call oopses. */
 576                         /* usb_kill_urb(write_urb_pool[i]); */
 577                         kfree(write_urb_pool[i]->transfer_buffer);
 578                         usb_free_urb (write_urb_pool[i]);
 579                 }
 580         }
 581
 582         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 583 }
 584
 585
 586 module_init(empeg_init);
 587 module_exit(empeg_exit);
 588
 589 MODULE_AUTHOR( DRIVER_AUTHOR );
 590 MODULE_DESCRIPTION( DRIVER_DESC );
 591 MODULE_LICENSE("GPL");
 592
 593 module_param(debug, bool, S_IRUGO | S_IWUSR);
 594 MODULE_PARM_DESC(debug, "Debug enabled or not");