root/include/linux/parport.h

INCLUDED FROM

DEFINITIONS

1. parport_yield
2. parport_yield_blocking
3. parport_generic_irq

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