include/linux/parport.h

   1 /*
   2  * Any part of this program may be used in documents licensed under
   3  * the GNU Free Documentation License, Version 1.1 or any later version
   4  * published by the Free Software Foundation.
   5  */
   6
   7 #ifndef _PARPORT_H_
   8 #define _PARPORT_H_
   9
  10 /* Start off with user-visible constants */
  11
  12 /* Maximum of 16 ports per machine */
  13 #define PARPORT_MAX  16
  14
  15 /* Magic numbers */
  16 #define PARPORT_IRQ_NONE  -1
  17 #define PARPORT_DMA_NONE  -1
  18 #define PARPORT_IRQ_AUTO  -2
  19 #define PARPORT_DMA_AUTO  -2
  20 #define PARPORT_DMA_NOFIFO -3
  21 #define PARPORT_DISABLE   -2
  22 #define PARPORT_IRQ_PROBEONLY -3
  23 #define PARPORT_IOHI_AUTO -1
  24
  25 #define PARPORT_CONTROL_STROBE    0x1
  26 #define PARPORT_CONTROL_AUTOFD    0x2
  27 #define PARPORT_CONTROL_INIT      0x4
  28 #define PARPORT_CONTROL_SELECT    0x8
  29
  30 #define PARPORT_STATUS_ERROR      0x8
  31 #define PARPORT_STATUS_SELECT     0x10
  32 #define PARPORT_STATUS_PAPEROUT   0x20
  33 #define PARPORT_STATUS_ACK        0x40
  34 #define PARPORT_STATUS_BUSY       0x80
  35
  36 /* Type classes for Plug-and-Play probe.  */
  37 typedef enum {
  38         PARPORT_CLASS_LEGACY = 0,       /* Non-IEEE1284 device */
  39         PARPORT_CLASS_PRINTER,
  40         PARPORT_CLASS_MODEM,
  41         PARPORT_CLASS_NET,
  42         PARPORT_CLASS_HDC,              /* Hard disk controller */
  43         PARPORT_CLASS_PCMCIA,
  44         PARPORT_CLASS_MEDIA,            /* Multimedia device */
  45         PARPORT_CLASS_FDC,              /* Floppy disk controller */
  46         PARPORT_CLASS_PORTS,
  47         PARPORT_CLASS_SCANNER,
  48         PARPORT_CLASS_DIGCAM,
  49         PARPORT_CLASS_OTHER,            /* Anything else */
  50         PARPORT_CLASS_UNSPEC,           /* No CLS field in ID */
  51         PARPORT_CLASS_SCSIADAPTER
  52 } parport_device_class;
  53
  54 /* The "modes" entry in parport is a bit field representing the
  55    capabilities of the hardware. */
  56 #define PARPORT_MODE_PCSPP      (1<<0) /* IBM PC registers available. */
  57 #define PARPORT_MODE_TRISTATE   (1<<1) /* Can tristate. */
  58 #define PARPORT_MODE_EPP        (1<<2) /* Hardware EPP. */
  59 #define PARPORT_MODE_ECP        (1<<3) /* Hardware ECP. */
  60 #define PARPORT_MODE_COMPAT     (1<<4) /* Hardware 'printer protocol'. */
  61 #define PARPORT_MODE_DMA        (1<<5) /* Hardware can DMA. */
  62 #define PARPORT_MODE_SAFEININT  (1<<6) /* SPP registers accessible in IRQ. */
  63
  64 /* IEEE1284 modes:
  65    Nibble mode, byte mode, ECP, ECPRLE and EPP are their own
  66    'extensibility request' values.  Others are special.
  67    'Real' ECP modes must have the IEEE1284_MODE_ECP bit set.  */
  68 #define IEEE1284_MODE_NIBBLE             0
  69 #define IEEE1284_MODE_BYTE              (1<<0)
  70 #define IEEE1284_MODE_COMPAT            (1<<8)
  71 #define IEEE1284_MODE_BECP              (1<<9) /* Bounded ECP mode */
  72 #define IEEE1284_MODE_ECP               (1<<4)
  73 #define IEEE1284_MODE_ECPRLE            (IEEE1284_MODE_ECP | (1<<5))
  74 #define IEEE1284_MODE_ECPSWE            (1<<10) /* Software-emulated */
  75 #define IEEE1284_MODE_EPP               (1<<6)
  76 #define IEEE1284_MODE_EPPSL             (1<<11) /* EPP 1.7 */
  77 #define IEEE1284_MODE_EPPSWE            (1<<12) /* Software-emulated */
  78 #define IEEE1284_DEVICEID               (1<<2)  /* This is a flag */
  79 #define IEEE1284_EXT_LINK               (1<<14) /* This flag causes the
  80                                                  * extensibility link to
  81                                                  * be requested, using
  82                                                  * bits 0-6. */
  83
  84 /* For the benefit of parport_read/write, you can use these with
  85  * parport_negotiate to use address operations.  They have no effect
  86  * other than to make parport_read/write use address transfers. */
  87 #define IEEE1284_ADDR                   (1<<13) /* This is a flag */
  88 #define IEEE1284_DATA                    0      /* So is this */
  89
  90 /* Flags for block transfer operations. */
  91 #define PARPORT_EPP_FAST                (1<<0) /* Unreliable counts. */
  92 #define PARPORT_W91284PIC               (1<<1) /* have a Warp9 w91284pic in the device */
  93
  94 /* The rest is for the kernel only */
  95 #ifdef __KERNEL__
  96
  97 #include <linux/jiffies.h>
  98 #include <linux/proc_fs.h>
  99 #include <linux/spinlock.h>
 100 #include <linux/wait.h>
 101 #include <linux/irqreturn.h>
 102 #include <linux/semaphore.h>
 103 #include <asm/ptrace.h>
 104
 105 /* Define this later. */
 106 struct parport;
 107 struct pardevice;
 108
 109 struct pc_parport_state {
 110         unsigned int ctr;
 111         unsigned int ecr;
 112 };
 113
 114 struct ax_parport_state {
 115         unsigned int ctr;
 116         unsigned int ecr;
 117         unsigned int dcsr;
 118 };
 119
 120 /* used by both parport_amiga and parport_mfc3 */
 121 struct amiga_parport_state {
 122        unsigned char data;     /* ciaa.prb */
 123        unsigned char datadir;  /* ciaa.ddrb */
 124        unsigned char status;   /* ciab.pra & 7 */
 125        unsigned char statusdir;/* ciab.ddrb & 7 */
 126 };
 127
 128 struct ax88796_parport_state {
 129         unsigned char cpr;
 130 };
 131
 132 struct ip32_parport_state {
 133         unsigned int dcr;
 134         unsigned int ecr;
 135 };
 136
 137 struct parport_state {
 138         union {
 139                 struct pc_parport_state pc;
 140                 /* ARC has no state. */
 141                 struct ax_parport_state ax;
 142                 struct amiga_parport_state amiga;
 143                 struct ax88796_parport_state ax88796;
 144                 /* Atari has not state. */
 145                 struct ip32_parport_state ip32;
 146                 void *misc;
 147         } u;
 148 };
 149
 150 struct parport_operations {
 151         /* IBM PC-style virtual registers. */
 152         void (*write_data)(struct parport *, unsigned char);
 153         unsigned char (*read_data)(struct parport *);
 154
 155         void (*write_control)(struct parport *, unsigned char);
 156         unsigned char (*read_control)(struct parport *);
 157         unsigned char (*frob_control)(struct parport *, unsigned char mask,
 158                                       unsigned char val);
 159
 160         unsigned char (*read_status)(struct parport *);
 161
 162         /* IRQs. */
 163         void (*enable_irq)(struct parport *);
 164         void (*disable_irq)(struct parport *);
 165
 166         /* Data direction. */
 167         void (*data_forward) (struct parport *);
 168         void (*data_reverse) (struct parport *);
 169
 170         /* For core parport code. */
 171         void (*init_state)(struct pardevice *, struct parport_state *);
 172         void (*save_state)(struct parport *, struct parport_state *);
 173         void (*restore_state)(struct parport *, struct parport_state *);
 174
 175         /* Block read/write */
 176         size_t (*epp_write_data) (struct parport *port, const void *buf,
 177                                   size_t len, int flags);
 178         size_t (*epp_read_data) (struct parport *port, void *buf, size_t len,
 179                                  int flags);
 180         size_t (*epp_write_addr) (struct parport *port, const void *buf,
 181                                   size_t len, int flags);
 182         size_t (*epp_read_addr) (struct parport *port, void *buf, size_t len,
 183                                  int flags);
 184
 185         size_t (*ecp_write_data) (struct parport *port, const void *buf,
 186                                   size_t len, int flags);
 187         size_t (*ecp_read_data) (struct parport *port, void *buf, size_t len,
 188                                  int flags);
 189         size_t (*ecp_write_addr) (struct parport *port, const void *buf,
 190                                   size_t len, int flags);
 191
 192         size_t (*compat_write_data) (struct parport *port, const void *buf,
 193                                      size_t len, int flags);
 194         size_t (*nibble_read_data) (struct parport *port, void *buf,
 195                                     size_t len, int flags);
 196         size_t (*byte_read_data) (struct parport *port, void *buf,
 197                                   size_t len, int flags);
 198         struct module *owner;
 199 };
 200
 201 struct parport_device_info {
 202         parport_device_class class;
 203         const char *class_name;
 204         const char *mfr;
 205         const char *model;
 206         const char *cmdset;
 207         const char *description;
 208 };
 209
 210 /* Each device can have two callback functions:
 211  *  1) a preemption function, called by the resource manager to request
 212  *     that the driver relinquish control of the port.  The driver should
 213  *     return zero if it agrees to release the port, and nonzero if it
 214  *     refuses.  Do not call parport_release() - the kernel will do this
 215  *     implicitly.
 216  *
 217  *  2) a wake-up function, called by the resource manager to tell drivers
 218  *     that the port is available to be claimed.  If a driver wants to use
 219  *     the port, it should call parport_claim() here.
 220  */
 221
 222 /* A parallel port device */
 223 struct pardevice {
 224         const char *name;
 225         struct parport *port;
 226         int daisy;
 227         int (*preempt)(void *);
 228         void (*wakeup)(void *);
 229         void *private;
 230         void (*irq_func)(void *);
 231         unsigned int flags;
 232         struct pardevice *next;
 233         struct pardevice *prev;
 234         struct parport_state *state;     /* saved status over preemption */
 235         wait_queue_head_t wait_q;
 236         unsigned long int time;
 237         unsigned long int timeslice;
 238         volatile long int timeout;
 239         unsigned long waiting;           /* long req'd for set_bit --RR */
 240         struct pardevice *waitprev;
 241         struct pardevice *waitnext;
 242         void * sysctl_table;
 243 };
 244
 245 /* IEEE1284 information */
 246
 247 /* IEEE1284 phases. These are exposed to userland through ppdev IOCTL
 248  * PP[GS]ETPHASE, so do not change existing values. */
 249 enum ieee1284_phase {
 250         IEEE1284_PH_FWD_DATA,
 251         IEEE1284_PH_FWD_IDLE,
 252         IEEE1284_PH_TERMINATE,
 253         IEEE1284_PH_NEGOTIATION,
 254         IEEE1284_PH_HBUSY_DNA,
 255         IEEE1284_PH_REV_IDLE,
 256         IEEE1284_PH_HBUSY_DAVAIL,
 257         IEEE1284_PH_REV_DATA,
 258         IEEE1284_PH_ECP_SETUP,
 259         IEEE1284_PH_ECP_FWD_TO_REV,
 260         IEEE1284_PH_ECP_REV_TO_FWD,
 261         IEEE1284_PH_ECP_DIR_UNKNOWN,
 262 };
 263 struct ieee1284_info {
 264         int mode;
 265         volatile enum ieee1284_phase phase;
 266         struct semaphore irq;
 267 };
 268
 269 /* A parallel port */
 270 struct parport {
 271         unsigned long base;     /* base address */
 272         unsigned long base_hi;  /* base address (hi - ECR) */
 273         unsigned int size;      /* IO extent */
 274         const char *name;
 275         unsigned int modes;
 276         int irq;                /* interrupt (or -1 for none) */
 277         int dma;
 278         int muxport;            /* which muxport (if any) this is */
 279         int portnum;            /* which physical parallel port (not mux) */
 280         struct device *dev;     /* Physical device associated with IO/DMA.
 281                                  * This may unfortulately be null if the
 282                                  * port has a legacy driver.
 283                                  */
 284
 285         struct parport *physport;
 286                                 /* If this is a non-default mux
 287                                    parport, i.e. we're a clone of a real
 288                                    physical port, this is a pointer to that
 289                                    port. The locking is only done in the
 290                                    real port.  For a clone port, the
 291                                    following structure members are
 292                                    meaningless: devices, cad, muxsel,
 293                                    waithead, waittail, flags, pdir,
 294                                    dev, ieee1284, *_lock.
 295
 296                                    It this is a default mux parport, or
 297                                    there is no mux involved, this points to
 298                                    ourself. */
 299
 300         struct pardevice *devices;
 301         struct pardevice *cad;  /* port owner */
 302         int daisy;              /* currently selected daisy addr */
 303         int muxsel;             /* currently selected mux port */
 304
 305         struct pardevice *waithead;
 306         struct pardevice *waittail;
 307
 308         struct list_head list;
 309         unsigned int flags;
 310
 311         void *sysctl_table;
 312         struct parport_device_info probe_info[5]; /* 0-3 + non-IEEE1284.3 */
 313         struct ieee1284_info ieee1284;
 314
 315         struct parport_operations *ops;
 316         void *private_data;     /* for lowlevel driver */
 317
 318         int number;             /* port index - the `n' in `parportn' */
 319         spinlock_t pardevice_lock;
 320         spinlock_t waitlist_lock;
 321         rwlock_t cad_lock;
 322
 323         int spintime;
 324         atomic_t ref_count;
 325
 326         unsigned long devflags;
 327 #define PARPORT_DEVPROC_REGISTERED      0
 328         struct pardevice *proc_device;  /* Currently register proc device */
 329
 330         struct list_head full_list;
 331         struct parport *slaves[3];
 332 };
 333
 334 #define DEFAULT_SPIN_TIME 500 /* us */
 335
 336 struct parport_driver {
 337         const char *name;
 338         void (*attach) (struct parport *);
 339         void (*detach) (struct parport *);
 340         struct list_head list;
 341 };
 342
 343 /* parport_register_port registers a new parallel port at the given
 344    address (if one does not already exist) and returns a pointer to it.
 345    This entails claiming the I/O region, IRQ and DMA.  NULL is returned
 346    if initialisation fails. */
 347 struct parport *parport_register_port(unsigned long base, int irq, int dma,
 348                                       struct parport_operations *ops);
 349
 350 /* Once a registered port is ready for high-level drivers to use, the
 351    low-level driver that registered it should announce it.  This will
 352    call the high-level drivers' attach() functions (after things like
 353    determining the IEEE 1284.3 topology of the port and collecting
 354    DeviceIDs). */
 355 void parport_announce_port (struct parport *port);
 356
 357 /* Unregister a port. */
 358 extern void parport_remove_port(struct parport *port);
 359
 360 /* Register a new high-level driver. */
 361 extern int parport_register_driver (struct parport_driver *);
 362
 363 /* Unregister a high-level driver. */
 364 extern void parport_unregister_driver (struct parport_driver *);
 365
 366 /* If parport_register_driver doesn't fit your needs, perhaps
 367  * parport_find_xxx does. */
 368 extern struct parport *parport_find_number (int);
 369 extern struct parport *parport_find_base (unsigned long);
 370
 371 /* generic irq handler, if it suits your needs */
 372 extern irqreturn_t parport_irq_handler(int irq, void *dev_id);
 373
 374 /* Reference counting for ports. */
 375 extern struct parport *parport_get_port (struct parport *);
 376 extern void parport_put_port (struct parport *);
 377
 378 /* parport_register_device declares that a device is connected to a
 379    port, and tells the kernel all it needs to know.
 380    - pf is the preemption function (may be NULL for no callback)
 381    - kf is the wake-up function (may be NULL for no callback)
 382    - irq_func is the interrupt handler (may be NULL for no interrupts)
 383    - handle is a user pointer that gets handed to callback functions.  */
 384 struct pardevice *parport_register_device(struct parport *port,
 385                           const char *name,
 386                           int (*pf)(void *), void (*kf)(void *),
 387                           void (*irq_func)(void *),
 388                           int flags, void *handle);
 389
 390 /* parport_unregister unlinks a device from the chain. */
 391 extern void parport_unregister_device(struct pardevice *dev);
 392
 393 /* parport_claim tries to gain ownership of the port for a particular
 394    driver.  This may fail (return non-zero) if another driver is busy.
 395    If this driver has registered an interrupt handler, it will be
 396    enabled.  */
 397 extern int parport_claim(struct pardevice *dev);
 398
 399 /* parport_claim_or_block is the same, but sleeps if the port cannot
 400    be claimed.  Return value is 1 if it slept, 0 normally and -errno
 401    on error.  */
 402 extern int parport_claim_or_block(struct pardevice *dev);
 403
 404 /* parport_release reverses a previous parport_claim.  This can never
 405    fail, though the effects are undefined (except that they are bad)
 406    if you didn't previously own the port.  Once you have released the
 407    port you should make sure that neither your code nor the hardware
 408    on the port tries to initiate any communication without first
 409    re-claiming the port.  If you mess with the port state (enabling
 410    ECP for example) you should clean up before releasing the port. */
 411
 412 extern void parport_release(struct pardevice *dev);
 413
 414 /**
 415  * parport_yield - relinquish a parallel port temporarily
 416  * @dev: a device on the parallel port
 417  *
 418  * This function relinquishes the port if it would be helpful to other
 419  * drivers to do so.  Afterwards it tries to reclaim the port using
 420  * parport_claim(), and the return value is the same as for
 421  * parport_claim().  If it fails, the port is left unclaimed and it is
 422  * the driver's responsibility to reclaim the port.
 423  *
 424  * The parport_yield() and parport_yield_blocking() functions are for
 425  * marking points in the driver at which other drivers may claim the
 426  * port and use their devices.  Yielding the port is similar to
 427  * releasing it and reclaiming it, but is more efficient because no
 428  * action is taken if there are no other devices needing the port.  In
 429  * fact, nothing is done even if there are other devices waiting but
 430  * the current device is still within its "timeslice".  The default
 431  * timeslice is half a second, but it can be adjusted via the /proc
 432  * interface.
 433  **/
 434 static __inline__ int parport_yield(struct pardevice *dev)
 435 {
 436         unsigned long int timeslip = (jiffies - dev->time);
 437         if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
 438                 return 0;
 439         parport_release(dev);
 440         return parport_claim(dev);
 441 }
 442
 443 /**
 444  * parport_yield_blocking - relinquish a parallel port temporarily
 445  * @dev: a device on the parallel port
 446  *
 447  * This function relinquishes the port if it would be helpful to other
 448  * drivers to do so.  Afterwards it tries to reclaim the port using
 449  * parport_claim_or_block(), and the return value is the same as for
 450  * parport_claim_or_block().
 451  **/
 452 static __inline__ int parport_yield_blocking(struct pardevice *dev)
 453 {
 454         unsigned long int timeslip = (jiffies - dev->time);
 455         if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
 456                 return 0;
 457         parport_release(dev);
 458         return parport_claim_or_block(dev);
 459 }
 460
 461 /* Flags used to identify what a device does. */
 462 #define PARPORT_DEV_TRAN                0       /* WARNING !! DEPRECATED !! */
 463 #define PARPORT_DEV_LURK                (1<<0)  /* WARNING !! DEPRECATED !! */
 464 #define PARPORT_DEV_EXCL                (1<<1)  /* Need exclusive access. */
 465
 466 #define PARPORT_FLAG_EXCL               (1<<1)  /* EXCL driver registered. */
 467
 468 /* IEEE1284 functions */
 469 extern void parport_ieee1284_interrupt (void *);
 470 extern int parport_negotiate (struct parport *, int mode);
 471 extern ssize_t parport_write (struct parport *, const void *buf, size_t len);
 472 extern ssize_t parport_read (struct parport *, void *buf, size_t len);
 473
 474 #define PARPORT_INACTIVITY_O_NONBLOCK 1
 475 extern long parport_set_timeout (struct pardevice *, long inactivity);
 476
 477 extern int parport_wait_event (struct parport *, long timeout);
 478 extern int parport_wait_peripheral (struct parport *port,
 479                                     unsigned char mask,
 480                                     unsigned char val);
 481 extern int parport_poll_peripheral (struct parport *port,
 482                                     unsigned char mask,
 483                                     unsigned char val,
 484                                     int usec);
 485
 486 /* For architectural drivers */
 487 extern size_t parport_ieee1284_write_compat (struct parport *,
 488                                              const void *, size_t, int);
 489 extern size_t parport_ieee1284_read_nibble (struct parport *,
 490                                             void *, size_t, int);
 491 extern size_t parport_ieee1284_read_byte (struct parport *,
 492                                           void *, size_t, int);
 493 extern size_t parport_ieee1284_ecp_read_data (struct parport *,
 494                                               void *, size_t, int);
 495 extern size_t parport_ieee1284_ecp_write_data (struct parport *,
 496                                                const void *, size_t, int);
 497 extern size_t parport_ieee1284_ecp_write_addr (struct parport *,
 498                                                const void *, size_t, int);
 499 extern size_t parport_ieee1284_epp_write_data (struct parport *,
 500                                                const void *, size_t, int);
 501 extern size_t parport_ieee1284_epp_read_data (struct parport *,
 502                                               void *, size_t, int);
 503 extern size_t parport_ieee1284_epp_write_addr (struct parport *,
 504                                                const void *, size_t, int);
 505 extern size_t parport_ieee1284_epp_read_addr (struct parport *,
 506                                               void *, size_t, int);
 507
 508 /* IEEE1284.3 functions */
 509 extern int parport_daisy_init (struct parport *port);
 510 extern void parport_daisy_fini (struct parport *port);
 511 extern struct pardevice *parport_open (int devnum, const char *name);
 512 extern void parport_close (struct pardevice *dev);
 513 extern ssize_t parport_device_id (int devnum, char *buffer, size_t len);
 514 extern void parport_daisy_deselect_all (struct parport *port);
 515 extern int parport_daisy_select (struct parport *port, int daisy, int mode);
 516
 517 /* Lowlevel drivers _can_ call this support function to handle irqs.  */
 518 static inline void parport_generic_irq(struct parport *port)
 519 {
 520         parport_ieee1284_interrupt (port);
 521         read_lock(&port->cad_lock);
 522         if (port->cad && port->cad->irq_func)
 523                 port->cad->irq_func(port->cad->private);
 524         read_unlock(&port->cad_lock);
 525 }
 526
 527 /* Prototypes from parport_procfs */
 528 extern int parport_proc_register(struct parport *pp);
 529 extern int parport_proc_unregister(struct parport *pp);
 530 extern int parport_device_proc_register(struct pardevice *device);
 531 extern int parport_device_proc_unregister(struct pardevice *device);
 532
 533 /* If PC hardware is the only type supported, we can optimise a bit.  */
 534 #if !defined(CONFIG_PARPORT_NOT_PC)
 535
 536 #include <linux/parport_pc.h>
 537 #define parport_write_data(p,x)            parport_pc_write_data(p,x)
 538 #define parport_read_data(p)               parport_pc_read_data(p)
 539 #define parport_write_control(p,x)         parport_pc_write_control(p,x)
 540 #define parport_read_control(p)            parport_pc_read_control(p)
 541 #define parport_frob_control(p,m,v)        parport_pc_frob_control(p,m,v)
 542 #define parport_read_status(p)             parport_pc_read_status(p)
 543 #define parport_enable_irq(p)              parport_pc_enable_irq(p)
 544 #define parport_disable_irq(p)             parport_pc_disable_irq(p)
 545 #define parport_data_forward(p)            parport_pc_data_forward(p)
 546 #define parport_data_reverse(p)            parport_pc_data_reverse(p)
 547
 548 #else  /*  !CONFIG_PARPORT_NOT_PC  */
 549
 550 /* Generic operations vector through the dispatch table. */
 551 #define parport_write_data(p,x)            (p)->ops->write_data(p,x)
 552 #define parport_read_data(p)               (p)->ops->read_data(p)
 553 #define parport_write_control(p,x)         (p)->ops->write_control(p,x)
 554 #define parport_read_control(p)            (p)->ops->read_control(p)
 555 #define parport_frob_control(p,m,v)        (p)->ops->frob_control(p,m,v)
 556 #define parport_read_status(p)             (p)->ops->read_status(p)
 557 #define parport_enable_irq(p)              (p)->ops->enable_irq(p)
 558 #define parport_disable_irq(p)             (p)->ops->disable_irq(p)
 559 #define parport_data_forward(p)            (p)->ops->data_forward(p)
 560 #define parport_data_reverse(p)            (p)->ops->data_reverse(p)
 561
 562 #endif /*  !CONFIG_PARPORT_NOT_PC  */
 563
 564 extern unsigned long parport_default_timeslice;
 565 extern int parport_default_spintime;
 566
 567 #endif /* __KERNEL__ */
 568 #endif /* _PARPORT_H_ */