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         dbg("%s - port %d", __FUNCTION__, port->number);
 161
 162         /* Force default termio settings */
 163         empeg_set_termios (port, NULL) ;
 164
 165         bytes_in = 0;
 166         bytes_out = 0;
 167
 168         /* Start reading from the device */
 169         usb_fill_bulk_urb(
 170                 port->read_urb,
 171                 serial->dev,
 172                 usb_rcvbulkpipe(serial->dev,
 173                         port->bulk_in_endpointAddress),
 174                 port->read_urb->transfer_buffer,
 175                 port->read_urb->transfer_buffer_length,
 176                 empeg_read_bulk_callback,
 177                 port);
 178
 179         result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 180
 181         if (result)
 182                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 183
 184         return result;
 185 }
 186
 187
 188 static void empeg_close (struct usb_serial_port *port, struct file * filp)
 189 {
 190         dbg("%s - port %d", __FUNCTION__, port->number);
 191
 192         /* shutdown our bulk read */
 193         usb_unlink_urb (port->read_urb);
 194         /* Uncomment the following line if you want to see some statistics in your syslog */
 195         /* dev_info (&port->dev, "Bytes In = %d  Bytes Out = %d\n", bytes_in, bytes_out); */
 196 }
 197
 198
 199 static int empeg_write (struct usb_serial_port *port, int from_user, const unsigned char *buf, int count)
 200 {
 201         struct usb_serial *serial = port->serial;
 202         struct urb *urb;
 203         const unsigned char *current_position = buf;
 204         unsigned long flags;
 205         int status;
 206         int i;
 207         int bytes_sent = 0;
 208         int transfer_size;
 209
 210         dbg("%s - port %d", __FUNCTION__, port->number);
 211
 212         while (count > 0) {
 213
 214                 /* try to find a free urb in our list of them */
 215                 urb = NULL;
 216
 217                 spin_lock_irqsave (&write_urb_pool_lock, flags);
 218
 219                 for (i = 0; i < NUM_URBS; ++i) {
 220                         if (write_urb_pool[i]->status != -EINPROGRESS) {
 221                                 urb = write_urb_pool[i];
 222                                 break;
 223                         }
 224                 }
 225
 226                 spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 227
 228                 if (urb == NULL) {
 229                         dbg("%s - no more free urbs", __FUNCTION__);
 230                         goto exit;
 231                 }
 232
 233                 if (urb->transfer_buffer == NULL) {
 234                         urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
 235                         if (urb->transfer_buffer == NULL) {
 236                                 dev_err(&port->dev, "%s no more kernel memory...\n", __FUNCTION__);
 237                                 goto exit;
 238                         }
 239                 }
 240
 241                 transfer_size = min (count, URB_TRANSFER_BUFFER_SIZE);
 242
 243                 if (from_user) {
 244                         if (copy_from_user (urb->transfer_buffer, current_position, transfer_size)) {
 245                                 bytes_sent = -EFAULT;
 246                                 break;
 247                         }
 248                 } else {
 249                         memcpy (urb->transfer_buffer, current_position, transfer_size);
 250                 }
 251
 252                 usb_serial_debug_data (__FILE__, __FUNCTION__, transfer_size, urb->transfer_buffer);
 253
 254                 /* build up our urb */
 255                 usb_fill_bulk_urb (
 256                         urb,
 257                         serial->dev,
 258                         usb_sndbulkpipe(serial->dev,
 259                                 port->bulk_out_endpointAddress),
 260                         urb->transfer_buffer,
 261                         transfer_size,
 262                         empeg_write_bulk_callback,
 263                         port);
 264
 265                 /* send it down the pipe */
 266                 status = usb_submit_urb(urb, GFP_ATOMIC);
 267                 if (status) {
 268                         dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __FUNCTION__, status);
 269                         bytes_sent = status;
 270                         break;
 271                 }
 272
 273                 current_position += transfer_size;
 274                 bytes_sent += transfer_size;
 275                 count -= transfer_size;
 276                 bytes_out += transfer_size;
 277
 278         }
 279
 280 exit:
 281         return bytes_sent;
 282
 283 }
 284
 285
 286 static int empeg_write_room (struct usb_serial_port *port)
 287 {
 288         unsigned long flags;
 289         int i;
 290         int room = 0;
 291
 292         dbg("%s - port %d", __FUNCTION__, port->number);
 293
 294         spin_lock_irqsave (&write_urb_pool_lock, flags);
 295
 296         /* tally up the number of bytes available */
 297         for (i = 0; i < NUM_URBS; ++i) {
 298                 if (write_urb_pool[i]->status != -EINPROGRESS) {
 299                         room += URB_TRANSFER_BUFFER_SIZE;
 300                 }
 301         }
 302
 303         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 304
 305         dbg("%s - returns %d", __FUNCTION__, room);
 306
 307         return (room);
 308
 309 }
 310
 311
 312 static int empeg_chars_in_buffer (struct usb_serial_port *port)
 313 {
 314         unsigned long flags;
 315         int i;
 316         int chars = 0;
 317
 318         dbg("%s - port %d", __FUNCTION__, port->number);
 319
 320         spin_lock_irqsave (&write_urb_pool_lock, flags);
 321
 322         /* tally up the number of bytes waiting */
 323         for (i = 0; i < NUM_URBS; ++i) {
 324                 if (write_urb_pool[i]->status == -EINPROGRESS) {
 325                         chars += URB_TRANSFER_BUFFER_SIZE;
 326                 }
 327         }
 328
 329         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 330
 331         dbg("%s - returns %d", __FUNCTION__, chars);
 332
 333         return (chars);
 334
 335 }
 336
 337
 338 static void empeg_write_bulk_callback (struct urb *urb, struct pt_regs *regs)
 339 {
 340         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 341
 342         dbg("%s - port %d", __FUNCTION__, port->number);
 343
 344         if (urb->status) {
 345                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 346                 return;
 347         }
 348
 349         schedule_work(&port->work);
 350 }
 351
 352
 353 static void empeg_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
 354 {
 355         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 356         struct tty_struct *tty;
 357         unsigned char *data = urb->transfer_buffer;
 358         int i;
 359         int result;
 360
 361         dbg("%s - port %d", __FUNCTION__, port->number);
 362
 363         if (urb->status) {
 364                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
 365                 return;
 366         }
 367
 368         usb_serial_debug_data (__FILE__, __FUNCTION__, urb->actual_length, data);
 369
 370         tty = port->tty;
 371
 372         if (urb->actual_length) {
 373                 for (i = 0; i < urb->actual_length ; ++i) {
 374                         /* gb - 2000/11/13
 375                          * If we insert too many characters we'll overflow the buffer.
 376                          * This means we'll lose bytes - Decidedly bad.
 377                          */
 378                         if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
 379                                 tty_flip_buffer_push(tty);
 380                                 }
 381                         tty_insert_flip_char(tty, data[i], 0);
 382                 }
 383                 /* gb - 2000/11/13
 384                  * Goes straight through instead of scheduling - if tty->low_latency is set.
 385                  */
 386                 tty_flip_buffer_push(tty);
 387                 bytes_in += urb->actual_length;
 388         }
 389
 390         /* Continue trying to always read  */
 391         usb_fill_bulk_urb(
 392                 port->read_urb,
 393                 port->serial->dev,
 394                 usb_rcvbulkpipe(port->serial->dev,
 395                         port->bulk_in_endpointAddress),
 396                 port->read_urb->transfer_buffer,
 397                 port->read_urb->transfer_buffer_length,
 398                 empeg_read_bulk_callback,
 399                 port);
 400
 401         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 402
 403         if (result)
 404                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __FUNCTION__, result);
 405
 406         return;
 407
 408 }
 409
 410
 411 static void empeg_throttle (struct usb_serial_port *port)
 412 {
 413         dbg("%s - port %d", __FUNCTION__, port->number);
 414         usb_unlink_urb (port->read_urb);
 415 }
 416
 417
 418 static void empeg_unthrottle (struct usb_serial_port *port)
 419 {
 420         int result;
 421
 422         dbg("%s - port %d", __FUNCTION__, port->number);
 423
 424         port->read_urb->dev = port->serial->dev;
 425
 426         result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 427
 428         if (result)
 429                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __FUNCTION__, result);
 430
 431         return;
 432 }
 433
 434
 435 static int  empeg_startup (struct usb_serial *serial)
 436 {
 437         int r;
 438
 439         dbg("%s", __FUNCTION__);
 440
 441         if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
 442                 err("active config #%d != 1 ??",
 443                         serial->dev->actconfig->desc.bConfigurationValue);
 444                 return -ENODEV;
 445         }
 446         dbg("%s - reset config", __FUNCTION__);
 447         r = usb_reset_configuration (serial->dev);
 448
 449         /* continue on with initialization */
 450         return r;
 451
 452 }
 453
 454
 455 static void empeg_shutdown (struct usb_serial *serial)
 456 {
 457         dbg ("%s", __FUNCTION__);
 458 }
 459
 460
 461 static int empeg_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 462 {
 463         dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
 464
 465         return -ENOIOCTLCMD;
 466 }
 467
 468
 469 static void empeg_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 470 {
 471
 472         dbg("%s - port %d", __FUNCTION__, port->number);
 473
 474         if ((!port->tty) || (!port->tty->termios)) {
 475                 dbg("%s - no tty structures", __FUNCTION__);
 476                 return;
 477         }
 478
 479         /*
 480          * The empeg-car player wants these particular tty settings.
 481          * You could, for example, change the baud rate, however the
 482          * player only supports 115200 (currently), so there is really
 483          * no point in support for changes to the tty settings.
 484          * (at least for now)
 485          *
 486          * The default requirements for this device are:
 487          */
 488         port->tty->termios->c_iflag
 489                 &= ~(IGNBRK     /* disable ignore break */
 490                 | BRKINT        /* disable break causes interrupt */
 491                 | PARMRK        /* disable mark parity errors */
 492                 | ISTRIP        /* disable clear high bit of input characters */
 493                 | INLCR         /* disable translate NL to CR */
 494                 | IGNCR         /* disable ignore CR */
 495                 | ICRNL         /* disable translate CR to NL */
 496                 | IXON);        /* disable enable XON/XOFF flow control */
 497
 498         port->tty->termios->c_oflag
 499                 &= ~OPOST;      /* disable postprocess output characters */
 500
 501         port->tty->termios->c_lflag
 502                 &= ~(ECHO       /* disable echo input characters */
 503                 | ECHONL        /* disable echo new line */
 504                 | ICANON        /* disable erase, kill, werase, and rprnt special characters */
 505                 | ISIG          /* disable interrupt, quit, and suspend special characters */
 506                 | IEXTEN);      /* disable non-POSIX special characters */
 507
 508         port->tty->termios->c_cflag
 509                 &= ~(CSIZE      /* no size */
 510                 | PARENB        /* disable parity bit */
 511                 | CBAUD);       /* clear current baud rate */
 512
 513         port->tty->termios->c_cflag
 514                 |= (CS8         /* character size 8 bits */
 515                 | B115200);     /* baud rate 115200 */
 516
 517         /*
 518          * Force low_latency on; otherwise the pushes are scheduled;
 519          * this is bad as it opens up the possibility of dropping bytes
 520          * on the floor.  We don't want to drop bytes on the floor. :)
 521          */
 522         port->tty->low_latency = 1;
 523
 524         /* Notify the tty driver that the termios have changed. */
 525         port->tty->ldisc.set_termios(port->tty, NULL);
 526
 527         return;
 528
 529 }
 530
 531
 532 static int __init empeg_init (void)
 533 {
 534         struct urb *urb;
 535         int i, retval;
 536
 537         /* create our write urb pool and transfer buffers */
 538         spin_lock_init (&write_urb_pool_lock);
 539         for (i = 0; i < NUM_URBS; ++i) {
 540                 urb = usb_alloc_urb(0, GFP_KERNEL);
 541                 write_urb_pool[i] = urb;
 542                 if (urb == NULL) {
 543                         err("No more urbs???");
 544                         continue;
 545                 }
 546
 547                 urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
 548                 if (!urb->transfer_buffer) {
 549                         err("%s - out of memory for urb buffers.",
 550                             __FUNCTION__);
 551                         continue;
 552                 }
 553         }
 554
 555         retval = usb_serial_register(&empeg_device);
 556         if (retval)
 557                 goto failed_usb_serial_register;
 558         retval = usb_register(&empeg_driver);
 559         if (retval)
 560                 goto failed_usb_register;
 561
 562         info(DRIVER_VERSION ":" DRIVER_DESC);
 563
 564         return 0;
 565 failed_usb_register:
 566         usb_serial_deregister(&empeg_device);
 567 failed_usb_serial_register:
 568         for (i = 0; i < NUM_URBS; ++i) {
 569                 if (write_urb_pool[i]) {
 570                         if (write_urb_pool[i]->transfer_buffer)
 571                                 kfree(write_urb_pool[i]->transfer_buffer);
 572                         usb_free_urb(write_urb_pool[i]);
 573                 }
 574         }
 575         return retval;
 576 }
 577
 578
 579 static void __exit empeg_exit (void)
 580 {
 581         int i;
 582         unsigned long flags;
 583
 584         usb_deregister(&empeg_driver);
 585         usb_serial_deregister (&empeg_device);
 586
 587         spin_lock_irqsave (&write_urb_pool_lock, flags);
 588
 589         for (i = 0; i < NUM_URBS; ++i) {
 590                 if (write_urb_pool[i]) {
 591                         /* FIXME - uncomment the following usb_unlink_urb call when
 592                          * the host controllers get fixed to set urb->dev = NULL after
 593                          * the urb is finished.  Otherwise this call oopses. */
 594                         /* usb_unlink_urb(write_urb_pool[i]); */
 595                         if (write_urb_pool[i]->transfer_buffer)
 596                                 kfree(write_urb_pool[i]->transfer_buffer);
 597                         usb_free_urb (write_urb_pool[i]);
 598                 }
 599         }
 600
 601         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 602 }
 603
 604
 605 module_init(empeg_init);
 606 module_exit(empeg_exit);
 607
 608 MODULE_AUTHOR( DRIVER_AUTHOR );
 609 MODULE_DESCRIPTION( DRIVER_DESC );
 610 MODULE_LICENSE("GPL");
 611
 612 MODULE_PARM(debug, "i");
 613 MODULE_PARM_DESC(debug, "Debug enabled or not");
 614