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
  67 #ifdef CONFIG_USB_SERIAL_DEBUG
  68         static int debug = 1;
  69 #else
  70         static int debug;
  71 #endif
  72
  73 #include "usb-serial.h"
  74
  75 /*
  76  * Version Information
  77  */
  78 #define DRIVER_VERSION "v1.2"
  79 #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Gary Brubaker <xavyer@ix.netcom.com>"
  80 #define DRIVER_DESC "USB Empeg Mark I/II Driver"
  81
  82 #define EMPEG_VENDOR_ID                 0x084f
  83 #define EMPEG_PRODUCT_ID                0x0001
  84
  85 /* function prototypes for an empeg-car player */
  86 static int  empeg_open                  (struct usb_serial_port *port, struct file *filp);
  87 static void empeg_close                 (struct usb_serial_port *port, struct file *filp);
  88 static int  empeg_write                 (struct usb_serial_port *port,
  89                                         int from_user,
  90                                         const unsigned char *buf,
  91                                         int count);
  92 static int  empeg_write_room            (struct usb_serial_port *port);
  93 static int  empeg_chars_in_buffer       (struct usb_serial_port *port);
  94 static void empeg_throttle              (struct usb_serial_port *port);
  95 static void empeg_unthrottle            (struct usb_serial_port *port);
  96 static int  empeg_startup               (struct usb_serial *serial);
  97 static void empeg_shutdown              (struct usb_serial *serial);
  98 static int  empeg_ioctl                 (struct usb_serial_port *port,
  99                                         struct file * file,
 100                                         unsigned int cmd,
 101                                         unsigned long arg);
 102 static void empeg_set_termios           (struct usb_serial_port *port, struct termios *old_termios);
 103 static void empeg_write_bulk_callback   (struct urb *urb, struct pt_regs *regs);
 104 static void empeg_read_bulk_callback    (struct urb *urb, struct pt_regs *regs);
 105
 106 static struct usb_device_id id_table [] = {
 107         { USB_DEVICE(EMPEG_VENDOR_ID, EMPEG_PRODUCT_ID) },
 108         { }                                     /* Terminating entry */
 109 };
 110
 111 MODULE_DEVICE_TABLE (usb, id_table);
 112
 113 static struct usb_driver empeg_driver = {
 114         .owner =        THIS_MODULE,
 115         .name =         "empeg",
 116         .probe =        usb_serial_probe,
 117         .disconnect =   usb_serial_disconnect,
 118         .id_table =     id_table,
 119 };
 120
 121 static struct usb_serial_device_type empeg_device = {
 122         .owner =                THIS_MODULE,
 123         .name =                 "Empeg",
 124         .id_table =             id_table,
 125         .num_interrupt_in =     0,
 126         .num_bulk_in =          1,
 127         .num_bulk_out =         1,
 128         .num_ports =            1,
 129         .open =                 empeg_open,
 130         .close =                empeg_close,
 131         .throttle =             empeg_throttle,
 132         .unthrottle =           empeg_unthrottle,
 133         .attach =               empeg_startup,
 134         .shutdown =             empeg_shutdown,
 135         .ioctl =                empeg_ioctl,
 136         .set_termios =          empeg_set_termios,
 137         .write =                empeg_write,
 138         .write_room =           empeg_write_room,
 139         .chars_in_buffer =      empeg_chars_in_buffer,
 140         .write_bulk_callback =  empeg_write_bulk_callback,
 141         .read_bulk_callback =   empeg_read_bulk_callback,
 142 };
 143
 144 #define NUM_URBS                        16
 145 #define URB_TRANSFER_BUFFER_SIZE        4096
 146
 147 static struct urb       *write_urb_pool[NUM_URBS];
 148 static spinlock_t       write_urb_pool_lock;
 149 static int              bytes_in;
 150 static int              bytes_out;
 151
 152 /******************************************************************************
 153  * Empeg specific driver functions
 154  ******************************************************************************/
 155 static int empeg_open (struct usb_serial_port *port, struct file *filp)
 156 {
 157         struct usb_serial *serial = port->serial;
 158         int result = 0;
 159
 160         if (port_paranoia_check (port, __FUNCTION__))
 161                 return -ENODEV;
 162
 163         dbg("%s - port %d", __FUNCTION__, port->number);
 164
 165         /* Force default termio settings */
 166         empeg_set_termios (port, NULL) ;
 167
 168         bytes_in = 0;
 169         bytes_out = 0;
 170
 171         /* Start reading from the device */
 172         usb_fill_bulk_urb(
 173                 port->read_urb,
 174                 serial->dev,
 175                 usb_rcvbulkpipe(serial->dev,
 176                         port->bulk_in_endpointAddress),
 177                 port->read_urb->transfer_buffer,
 178                 port->read_urb->transfer_buffer_length,
 179                 empeg_read_bulk_callback,
 180                 port);
 181
 182         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 183
 184         if (result)
 185                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 186
 187         return result;
 188 }
 189
 190
 191 static void empeg_close (struct usb_serial_port *port, struct file * filp)
 192 {
 193         struct usb_serial *serial;
 194
 195         if (port_paranoia_check (port, __FUNCTION__))
 196                 return;
 197
 198         dbg("%s - port %d", __FUNCTION__, port->number);
 199
 200         serial = get_usb_serial (port, __FUNCTION__);
 201         if (!serial)
 202                 return;
 203
 204         if (serial->dev) {
 205                 /* shutdown our bulk read */
 206                 usb_unlink_urb (port->read_urb);
 207         }
 208         /* Uncomment the following line if you want to see some statistics in your syslog */
 209         /* dev_info (&port->dev, "Bytes In = %d  Bytes Out = %d\n", bytes_in, bytes_out); */
 210 }
 211
 212
 213 static int empeg_write (struct usb_serial_port *port, int from_user, const unsigned char *buf, int count)
 214 {
 215         struct usb_serial *serial = port->serial;
 216         struct urb *urb;
 217         const unsigned char *current_position = buf;
 218         unsigned long flags;
 219         int status;
 220         int i;
 221         int bytes_sent = 0;
 222         int transfer_size;
 223
 224         dbg("%s - port %d", __FUNCTION__, port->number);
 225
 226         while (count > 0) {
 227
 228                 /* try to find a free urb in our list of them */
 229                 urb = NULL;
 230
 231                 spin_lock_irqsave (&write_urb_pool_lock, flags);
 232
 233                 for (i = 0; i < NUM_URBS; ++i) {
 234                         if (write_urb_pool[i]->status != -EINPROGRESS) {
 235                                 urb = write_urb_pool[i];
 236                                 break;
 237                         }
 238                 }
 239
 240                 spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 241
 242                 if (urb == NULL) {
 243                         dbg("%s - no more free urbs", __FUNCTION__);
 244                         goto exit;
 245                 }
 246
 247                 if (urb->transfer_buffer == NULL) {
 248                         urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
 249                         if (urb->transfer_buffer == NULL) {
 250                                 dev_err(&port->dev, "%s no more kernel memory...\n", __FUNCTION__);
 251                                 goto exit;
 252                         }
 253                 }
 254
 255                 transfer_size = min (count, URB_TRANSFER_BUFFER_SIZE);
 256
 257                 if (from_user) {
 258                         if (copy_from_user (urb->transfer_buffer, current_position, transfer_size)) {
 259                                 bytes_sent = -EFAULT;
 260                                 break;
 261                         }
 262                 } else {
 263                         memcpy (urb->transfer_buffer, current_position, transfer_size);
 264                 }
 265
 266                 usb_serial_debug_data (__FILE__, __FUNCTION__, transfer_size, urb->transfer_buffer);
 267
 268                 /* build up our urb */
 269                 usb_fill_bulk_urb (
 270                         urb,
 271                         serial->dev,
 272                         usb_sndbulkpipe(serial->dev,
 273                                 port->bulk_out_endpointAddress),
 274                         urb->transfer_buffer,
 275                         transfer_size,
 276                         empeg_write_bulk_callback,
 277                         port);
 278
 279                 /* send it down the pipe */
 280                 status = usb_submit_urb(urb, GFP_ATOMIC);
 281                 if (status) {
 282                         dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __FUNCTION__, status);
 283                         bytes_sent = status;
 284                         break;
 285                 }
 286
 287                 current_position += transfer_size;
 288                 bytes_sent += transfer_size;
 289                 count -= transfer_size;
 290                 bytes_out += transfer_size;
 291
 292         }
 293
 294 exit:
 295         return bytes_sent;
 296
 297 }
 298
 299
 300 static int empeg_write_room (struct usb_serial_port *port)
 301 {
 302         unsigned long flags;
 303         int i;
 304         int room = 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 available */
 311         for (i = 0; i < NUM_URBS; ++i) {
 312                 if (write_urb_pool[i]->status != -EINPROGRESS) {
 313                         room += URB_TRANSFER_BUFFER_SIZE;
 314                 }
 315         }
 316
 317         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 318
 319         dbg("%s - returns %d", __FUNCTION__, room);
 320
 321         return (room);
 322
 323 }
 324
 325
 326 static int empeg_chars_in_buffer (struct usb_serial_port *port)
 327 {
 328         unsigned long flags;
 329         int i;
 330         int chars = 0;
 331
 332         dbg("%s - port %d", __FUNCTION__, port->number);
 333
 334         spin_lock_irqsave (&write_urb_pool_lock, flags);
 335
 336         /* tally up the number of bytes waiting */
 337         for (i = 0; i < NUM_URBS; ++i) {
 338                 if (write_urb_pool[i]->status == -EINPROGRESS) {
 339                         chars += URB_TRANSFER_BUFFER_SIZE;
 340                 }
 341         }
 342
 343         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 344
 345         dbg("%s - returns %d", __FUNCTION__, chars);
 346
 347         return (chars);
 348
 349 }
 350
 351
 352 static void empeg_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 353 {
 354         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 355
 356         if (port_paranoia_check (port, __FUNCTION__))
 357                 return;
 358
 359         dbg("%s - port %d", __FUNCTION__, port->number);
 360
 361         if (urb->status) {
 362                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 363                 return;
 364         }
 365
 366         schedule_work(&port->work);
 367 }
 368
 369
 370 static void empeg_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 371 {
 372         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 373         struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
 374         struct tty_struct *tty;
 375         unsigned char *data = urb->transfer_buffer;
 376         int i;
 377         int result;
 378
 379         if (port_paranoia_check (port, __FUNCTION__))
 380                 return;
 381
 382         dbg("%s - port %d", __FUNCTION__, port->number);
 383
 384         if (!serial) {
 385                 dbg("%s - bad serial pointer, exiting", __FUNCTION__);
 386                 return;
 387         }
 388
 389         if (urb->status) {
 390                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
 391                 return;
 392         }
 393
 394         usb_serial_debug_data (__FILE__, __FUNCTION__, urb->actual_length, data);
 395
 396         tty = port->tty;
 397
 398         if (urb->actual_length) {
 399                 for (i = 0; i < urb->actual_length ; ++i) {
 400                         /* gb - 2000/11/13
 401                          * If we insert too many characters we'll overflow the buffer.
 402                          * This means we'll lose bytes - Decidedly bad.
 403                          */
 404                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
 405                                 tty_flip_buffer_push(tty);
 406                                 }
 407                         tty_insert_flip_char(tty, data[i], 0);
 408                 }
 409                 /* gb - 2000/11/13
 410                  * Goes straight through instead of scheduling - if tty->low_latency is set.
 411                  */
 412                 tty_flip_buffer_push(tty);
 413                 bytes_in += urb->actual_length;
 414         }
 415
 416         /* Continue trying to always read  */
 417         usb_fill_bulk_urb(
 418                 port->read_urb,
 419                 serial->dev,
 420                 usb_rcvbulkpipe(serial->dev,
 421                         port->bulk_in_endpointAddress),
 422                 port->read_urb->transfer_buffer,
 423                 port->read_urb->transfer_buffer_length,
 424                 empeg_read_bulk_callback,
 425                 port);
 426
 427         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 428
 429         if (result)
 430                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 431
 432         return;
 433
 434 }
 435
 436
 437 static void empeg_throttle (struct usb_serial_port *port)
 438 {
 439         dbg("%s - port %d", __FUNCTION__, port->number);
 440         usb_unlink_urb (port->read_urb);
 441 }
 442
 443
 444 static void empeg_unthrottle (struct usb_serial_port *port)
 445 {
 446         int result;
 447
 448         dbg("%s - port %d", __FUNCTION__, port->number);
 449
 450         port->read_urb->dev = port->serial->dev;
 451
 452         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 453
 454         if (result)
 455                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 456
 457         return;
 458 }
 459
 460
 461 static int  empeg_startup (struct usb_serial *serial)
 462 {
 463         int r;
 464
 465         dbg("%s", __FUNCTION__);
 466
 467         if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
 468                 err("active config #%d != 1 ??",
 469                         serial->dev->actconfig->desc.bConfigurationValue);
 470                 return -ENODEV;
 471         }
 472         dbg("%s - reset config", __FUNCTION__);
 473         r = usb_reset_configuration (serial->dev);
 474
 475         /* continue on with initialization */
 476         return r;
 477
 478 }
 479
 480
 481 static void empeg_shutdown (struct usb_serial *serial)
 482 {
 483         dbg ("%s", __FUNCTION__);
 484 }
 485
 486
 487 static int empeg_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 488 {
 489         dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
 490
 491         return -ENOIOCTLCMD;
 492 }
 493
 494
 495 static void empeg_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 496 {
 497
 498         dbg("%s - port %d", __FUNCTION__, port->number);
 499
 500         if ((!port->tty) || (!port->tty->termios)) {
 501                 dbg("%s - no tty structures", __FUNCTION__);
 502                 return;
 503         }
 504
 505         /*
 506          * The empeg-car player wants these particular tty settings.
 507          * You could, for example, change the baud rate, however the
 508          * player only supports 115200 (currently), so there is really
 509          * no point in support for changes to the tty settings.
 510          * (at least for now)
 511          *
 512          * The default requirements for this device are:
 513          */
 514         port->tty->termios->c_iflag
 515                 &= ~(IGNBRK     /* disable ignore break */
 516                 | BRKINT        /* disable break causes interrupt */
 517                 | PARMRK        /* disable mark parity errors */
 518                 | ISTRIP        /* disable clear high bit of input characters */
 519                 | INLCR         /* disable translate NL to CR */
 520                 | IGNCR         /* disable ignore CR */
 521                 | ICRNL         /* disable translate CR to NL */
 522                 | IXON);        /* disable enable XON/XOFF flow control */
 523
 524         port->tty->termios->c_oflag
 525                 &= ~OPOST;      /* disable postprocess output characters */
 526
 527         port->tty->termios->c_lflag
 528                 &= ~(ECHO       /* disable echo input characters */
 529                 | ECHONL        /* disable echo new line */
 530                 | ICANON        /* disable erase, kill, werase, and rprnt special characters */
 531                 | ISIG          /* disable interrupt, quit, and suspend special characters */
 532                 | IEXTEN);      /* disable non-POSIX special characters */
 533
 534         port->tty->termios->c_cflag
 535                 &= ~(CSIZE      /* no size */
 536                 | PARENB        /* disable parity bit */
 537                 | CBAUD);       /* clear current baud rate */
 538
 539         port->tty->termios->c_cflag
 540                 |= (CS8         /* character size 8 bits */
 541                 | B115200);     /* baud rate 115200 */
 542
 543         /*
 544          * Force low_latency on; otherwise the pushes are scheduled;
 545          * this is bad as it opens up the possibility of dropping bytes
 546          * on the floor.  We don't want to drop bytes on the floor. :)
 547          */
 548         port->tty->low_latency = 1;
 549
 550         /* Notify the tty driver that the termios have changed. */
 551         port->tty->ldisc.set_termios(port->tty, NULL);
 552
 553         return;
 554
 555 }
 556
 557
 558 static int __init empeg_init (void)
 559 {
 560         struct urb *urb;
 561         int i, retval;
 562
 563         /* create our write urb pool and transfer buffers */
 564         spin_lock_init (&write_urb_pool_lock);
 565         for (i = 0; i < NUM_URBS; ++i) {
 566                 urb = usb_alloc_urb(0, GFP_KERNEL);
 567                 write_urb_pool[i] = urb;
 568                 if (urb == NULL) {
 569                         err("No more urbs???");
 570                         continue;
 571                 }
 572
 573                 urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
 574                 if (!urb->transfer_buffer) {
 575                         err("%s - out of memory for urb buffers.",
 576                             __FUNCTION__);
 577                         continue;
 578                 }
 579         }
 580
 581         retval = usb_serial_register(&empeg_device);
 582         if (retval)
 583                 goto failed_usb_serial_register;
 584         retval = usb_register(&empeg_driver);
 585         if (retval)
 586                 goto failed_usb_register;
 587
 588         info(DRIVER_VERSION ":" DRIVER_DESC);
 589
 590         return 0;
 591 failed_usb_register:
 592         usb_serial_deregister(&empeg_device);
 593 failed_usb_serial_register:
 594         for (i = 0; i < NUM_URBS; ++i) {
 595                 if (write_urb_pool[i]) {
 596                         if (write_urb_pool[i]->transfer_buffer)
 597                                 kfree(write_urb_pool[i]->transfer_buffer);
 598                         usb_free_urb(write_urb_pool[i]);
 599                 }
 600         }
 601         return retval;
 602 }
 603
 604
 605 static void __exit empeg_exit (void)
 606 {
 607         int i;
 608         unsigned long flags;
 609
 610         usb_deregister(&empeg_driver);
 611         usb_serial_deregister (&empeg_device);
 612
 613         spin_lock_irqsave (&write_urb_pool_lock, flags);
 614
 615         for (i = 0; i < NUM_URBS; ++i) {
 616                 if (write_urb_pool[i]) {
 617                         /* FIXME - uncomment the following usb_unlink_urb call when
 618                          * the host controllers get fixed to set urb->dev = NULL after
 619                          * the urb is finished.  Otherwise this call oopses. */
 620                         /* usb_unlink_urb(write_urb_pool[i]); */
 621                         if (write_urb_pool[i]->transfer_buffer)
 622                                 kfree(write_urb_pool[i]->transfer_buffer);
 623                         usb_free_urb (write_urb_pool[i]);
 624                 }
 625         }
 626
 627         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 628 }
 629
 630
 631 module_init(empeg_init);
 632 module_exit(empeg_exit);
 633
 634 MODULE_AUTHOR( DRIVER_AUTHOR );
 635 MODULE_DESCRIPTION( DRIVER_DESC );
 636 MODULE_LICENSE("GPL");
 637
 638 MODULE_PARM(debug, "i");
 639 MODULE_PARM_DESC(debug, "Debug enabled or not");
 640