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);
 104 static void empeg_read_bulk_callback    (struct urb *urb);
 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_serial_device_type empeg_device = {
 114         .owner =                THIS_MODULE,
 115         .name =                 "Empeg",
 116         .id_table =             id_table,
 117         .num_interrupt_in =     0,
 118         .num_bulk_in =          1,
 119         .num_bulk_out =         1,
 120         .num_ports =            1,
 121         .open =                 empeg_open,
 122         .close =                empeg_close,
 123         .throttle =             empeg_throttle,
 124         .unthrottle =           empeg_unthrottle,
 125         .startup =              empeg_startup,
 126         .shutdown =             empeg_shutdown,
 127         .ioctl =                empeg_ioctl,
 128         .set_termios =          empeg_set_termios,
 129         .write =                empeg_write,
 130         .write_room =           empeg_write_room,
 131         .chars_in_buffer =      empeg_chars_in_buffer,
 132         .write_bulk_callback =  empeg_write_bulk_callback,
 133         .read_bulk_callback =   empeg_read_bulk_callback,
 134 };
 135
 136 #define NUM_URBS                        16
 137 #define URB_TRANSFER_BUFFER_SIZE        4096
 138
 139 static struct urb       *write_urb_pool[NUM_URBS];
 140 static spinlock_t       write_urb_pool_lock;
 141 static int              bytes_in;
 142 static int              bytes_out;
 143
 144 /******************************************************************************
 145  * Empeg specific driver functions
 146  ******************************************************************************/
 147 static int empeg_open (struct usb_serial_port *port, struct file *filp)
 148 {
 149         struct usb_serial *serial = port->serial;
 150         int result = 0;;
 151
 152         if (port_paranoia_check (port, __FUNCTION__))
 153                 return -ENODEV;
 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         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         port->read_urb->transfer_flags |= USB_QUEUE_BULK;
 175
 176         result = usb_submit_urb(port->read_urb);
 177
 178         if (result)
 179                 err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
 180
 181         return result;
 182 }
 183
 184
 185 static void empeg_close (struct usb_serial_port *port, struct file * filp)
 186 {
 187         struct usb_serial *serial;
 188
 189         if (port_paranoia_check (port, __FUNCTION__))
 190                 return;
 191
 192         dbg("%s - port %d", __FUNCTION__, port->number);
 193
 194         serial = get_usb_serial (port, __FUNCTION__);
 195         if (!serial)
 196                 return;
 197
 198         if (serial->dev) {
 199                 /* shutdown our bulk read */
 200                 usb_unlink_urb (port->read_urb);
 201         }
 202         /* Uncomment the following line if you want to see some statistics in your syslog */
 203         /* info ("Bytes In = %d  Bytes Out = %d", bytes_in, bytes_out); */
 204 }
 205
 206
 207 static int empeg_write (struct usb_serial_port *port, int from_user, const unsigned char *buf, int count)
 208 {
 209         struct usb_serial *serial = port->serial;
 210         struct urb *urb;
 211         const unsigned char *current_position = buf;
 212         unsigned long flags;
 213         int status;
 214         int i;
 215         int bytes_sent = 0;
 216         int transfer_size;
 217
 218         dbg("%s - port %d", __FUNCTION__, port->number);
 219
 220         usb_serial_debug_data (__FILE__, __FUNCTION__, count, buf);
 221
 222         while (count > 0) {
 223
 224                 /* try to find a free urb in our list of them */
 225                 urb = NULL;
 226
 227                 spin_lock_irqsave (&write_urb_pool_lock, flags);
 228
 229                 for (i = 0; i < NUM_URBS; ++i) {
 230                         if (write_urb_pool[i]->status != -EINPROGRESS) {
 231                                 urb = write_urb_pool[i];
 232                                 break;
 233                         }
 234                 }
 235
 236                 spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 237
 238                 if (urb == NULL) {
 239                         dbg("%s - no more free urbs", __FUNCTION__);
 240                         goto exit;
 241                 }
 242
 243                 if (urb->transfer_buffer == NULL) {
 244                         urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
 245                         if (urb->transfer_buffer == NULL) {
 246                                 err("%s no more kernel memory...", __FUNCTION__);
 247                                 goto exit;
 248                         }
 249                 }
 250
 251                 transfer_size = min (count, URB_TRANSFER_BUFFER_SIZE);
 252
 253                 if (from_user) {
 254                         if (copy_from_user (urb->transfer_buffer, current_position, transfer_size)) {
 255                                 bytes_sent = -EFAULT;
 256                                 break;
 257                         }
 258                 } else {
 259                         memcpy (urb->transfer_buffer, current_position, transfer_size);
 260                 }
 261
 262                 /* build up our urb */
 263                 FILL_BULK_URB (
 264                         urb,
 265                         serial->dev,
 266                         usb_sndbulkpipe(serial->dev,
 267                                 port->bulk_out_endpointAddress),
 268                         urb->transfer_buffer,
 269                         transfer_size,
 270                         empeg_write_bulk_callback,
 271                         port);
 272
 273                 urb->transfer_flags |= USB_QUEUE_BULK;
 274
 275                 /* send it down the pipe */
 276                 status = usb_submit_urb(urb);
 277                 if (status) {
 278                         err("%s - usb_submit_urb(write bulk) failed with status = %d", __FUNCTION__, status);
 279                         bytes_sent = status;
 280                         break;
 281                 }
 282
 283                 current_position += transfer_size;
 284                 bytes_sent += transfer_size;
 285                 count -= transfer_size;
 286                 bytes_out += transfer_size;
 287
 288         }
 289
 290 exit:
 291         return bytes_sent;
 292
 293 }
 294
 295
 296 static int empeg_write_room (struct usb_serial_port *port)
 297 {
 298         unsigned long flags;
 299         int i;
 300         int room = 0;
 301
 302         dbg("%s - port %d", __FUNCTION__, port->number);
 303
 304         spin_lock_irqsave (&write_urb_pool_lock, flags);
 305
 306         /* tally up the number of bytes available */
 307         for (i = 0; i < NUM_URBS; ++i) {
 308                 if (write_urb_pool[i]->status != -EINPROGRESS) {
 309                         room += URB_TRANSFER_BUFFER_SIZE;
 310                 }
 311         }
 312
 313         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 314
 315         dbg("%s - returns %d", __FUNCTION__, room);
 316
 317         return (room);
 318
 319 }
 320
 321
 322 static int empeg_chars_in_buffer (struct usb_serial_port *port)
 323 {
 324         unsigned long flags;
 325         int i;
 326         int chars = 0;
 327
 328         dbg("%s - port %d", __FUNCTION__, port->number);
 329
 330         spin_lock_irqsave (&write_urb_pool_lock, flags);
 331
 332         /* tally up the number of bytes waiting */
 333         for (i = 0; i < NUM_URBS; ++i) {
 334                 if (write_urb_pool[i]->status == -EINPROGRESS) {
 335                         chars += URB_TRANSFER_BUFFER_SIZE;
 336                 }
 337         }
 338
 339         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 340
 341         dbg("%s - returns %d", __FUNCTION__, chars);
 342
 343         return (chars);
 344
 345 }
 346
 347
 348 static void empeg_write_bulk_callback (struct urb *urb)
 349 {
 350         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 351
 352         if (port_paranoia_check (port, __FUNCTION__))
 353                 return;
 354
 355         dbg("%s - port %d", __FUNCTION__, port->number);
 356
 357         if (urb->status) {
 358                 dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
 359                 return;
 360         }
 361
 362         queue_task(&port->tqueue, &tq_immediate);
 363         mark_bh(IMMEDIATE_BH);
 364
 365         return;
 366
 367 }
 368
 369
 370 static void empeg_read_bulk_callback (struct urb *urb)
 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         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         port->read_urb->transfer_flags |= USB_QUEUE_BULK;
 428
 429         result = usb_submit_urb(port->read_urb);
 430
 431         if (result)
 432                 err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
 433
 434         return;
 435
 436 }
 437
 438
 439 static void empeg_throttle (struct usb_serial_port *port)
 440 {
 441         dbg("%s - port %d", __FUNCTION__, port->number);
 442         usb_unlink_urb (port->read_urb);
 443 }
 444
 445
 446 static void empeg_unthrottle (struct usb_serial_port *port)
 447 {
 448         int result;
 449
 450         dbg("%s - port %d", __FUNCTION__, port->number);
 451
 452         port->read_urb->dev = port->serial->dev;
 453
 454         result = usb_submit_urb(port->read_urb);
 455
 456         if (result)
 457                 err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
 458
 459         return;
 460 }
 461
 462
 463 static int  empeg_startup (struct usb_serial *serial)
 464 {
 465
 466         dbg("%s", __FUNCTION__);
 467
 468         dbg("%s - Set config to 1", __FUNCTION__);
 469         usb_set_configuration (serial->dev, 1);
 470
 471         /* continue on with initialization */
 472         return 0;
 473
 474 }
 475
 476
 477 static void empeg_shutdown (struct usb_serial *serial)
 478 {
 479         dbg ("%s", __FUNCTION__);
 480 }
 481
 482
 483 static int empeg_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 484 {
 485         dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);
 486
 487         return -ENOIOCTLCMD;
 488 }
 489
 490
 491 static void empeg_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 492 {
 493
 494         dbg("%s - port %d", __FUNCTION__, port->number);
 495
 496         if ((!port->tty) || (!port->tty->termios)) {
 497                 dbg("%s - no tty structures", __FUNCTION__);
 498                 return;
 499         }
 500
 501         /*
 502          * The empeg-car player wants these particular tty settings.
 503          * You could, for example, change the baud rate, however the
 504          * player only supports 115200 (currently), so there is really
 505          * no point in support for changes to the tty settings.
 506          * (at least for now)
 507          *
 508          * The default requirements for this device are:
 509          */
 510         port->tty->termios->c_iflag
 511                 &= ~(IGNBRK     /* disable ignore break */
 512                 | BRKINT        /* disable break causes interrupt */
 513                 | PARMRK        /* disable mark parity errors */
 514                 | ISTRIP        /* disable clear high bit of input characters */
 515                 | INLCR         /* disable translate NL to CR */
 516                 | IGNCR         /* disable ignore CR */
 517                 | ICRNL         /* disable translate CR to NL */
 518                 | IXON);        /* disable enable XON/XOFF flow control */
 519
 520         port->tty->termios->c_oflag
 521                 &= ~OPOST;      /* disable postprocess output characters */
 522
 523         port->tty->termios->c_lflag
 524                 &= ~(ECHO       /* disable echo input characters */
 525                 | ECHONL        /* disable echo new line */
 526                 | ICANON        /* disable erase, kill, werase, and rprnt special characters */
 527                 | ISIG          /* disable interrupt, quit, and suspend special characters */
 528                 | IEXTEN);      /* disable non-POSIX special characters */
 529
 530         port->tty->termios->c_cflag
 531                 &= ~(CSIZE      /* no size */
 532                 | PARENB        /* disable parity bit */
 533                 | CBAUD);       /* clear current baud rate */
 534
 535         port->tty->termios->c_cflag
 536                 |= (CS8         /* character size 8 bits */
 537                 | B115200);     /* baud rate 115200 */
 538
 539         /*
 540          * Force low_latency on; otherwise the pushes are scheduled;
 541          * this is bad as it opens up the possibility of dropping bytes
 542          * on the floor.  We don't want to drop bytes on the floor. :)
 543          */
 544         port->tty->low_latency = 1;
 545
 546         /* Notify the tty driver that the termios have changed. */
 547         port->tty->ldisc.set_termios(port->tty, NULL);
 548
 549         return;
 550
 551 }
 552
 553
 554 static int __init empeg_init (void)
 555 {
 556         struct urb *urb;
 557         int i;
 558
 559         usb_serial_register (&empeg_device);
 560
 561         /* create our write urb pool and transfer buffers */
 562         spin_lock_init (&write_urb_pool_lock);
 563         for (i = 0; i < NUM_URBS; ++i) {
 564                 urb = usb_alloc_urb(0);
 565                 write_urb_pool[i] = urb;
 566                 if (urb == NULL) {
 567                         err("No more urbs???");
 568                         continue;
 569                 }
 570
 571                 urb->transfer_buffer = NULL;
 572                 urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
 573                 if (!urb->transfer_buffer) {
 574                         err("%s - out of memory for urb buffers.",
 575                             __FUNCTION__);
 576                         continue;
 577                 }
 578         }
 579
 580         info(DRIVER_VERSION ":" DRIVER_DESC);
 581
 582         return 0;
 583
 584 }
 585
 586
 587 static void __exit empeg_exit (void)
 588 {
 589         int i;
 590         unsigned long flags;
 591
 592         usb_serial_deregister (&empeg_device);
 593
 594         spin_lock_irqsave (&write_urb_pool_lock, flags);
 595
 596         for (i = 0; i < NUM_URBS; ++i) {
 597                 if (write_urb_pool[i]) {
 598                         /* FIXME - uncomment the following usb_unlink_urb call when
 599                          * the host controllers get fixed to set urb->dev = NULL after
 600                          * the urb is finished.  Otherwise this call oopses. */
 601                         /* usb_unlink_urb(write_urb_pool[i]); */
 602                         if (write_urb_pool[i]->transfer_buffer)
 603                                 kfree(write_urb_pool[i]->transfer_buffer);
 604                         usb_free_urb (write_urb_pool[i]);
 605                 }
 606         }
 607
 608         spin_unlock_irqrestore (&write_urb_pool_lock, flags);
 609
 610 }
 611
 612
 613 module_init(empeg_init);
 614 module_exit(empeg_exit);
 615
 616 MODULE_AUTHOR( DRIVER_AUTHOR );
 617 MODULE_DESCRIPTION( DRIVER_DESC );
 618 MODULE_LICENSE("GPL");
 619
 620 MODULE_PARM(debug, "i");
 621 MODULE_PARM_DESC(debug, "Debug enabled or not");
 622