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  
301  /**
302   *	parport_register_driver - register a parallel port device driver
303   *	@driver: structure describing the driver
304   *
305   *	This can be called by a parallel port device driver in order
306   *	to receive notifications about ports being found in the
307   *	system, as well as ports no longer available.
308   *
309   *	If devmodel is true then the new device model is used
310   *	for registration.
311   *
312   *	The @driver structure is allocated by the caller and must not be
313   *	deallocated until after calling parport_unregister_driver().
314   *
315   *	If using the non device model:
316   *	The driver's attach() function may block.  The port that
317   *	attach() is given will be valid for the duration of the
318   *	callback, but if the driver wants to take a copy of the
319   *	pointer it must call parport_get_port() to do so.  Calling
320   *	parport_register_device() on that port will do this for you.
321   *
322   *	The driver's detach() function may block.  The port that
323   *	detach() is given will be valid for the duration of the
324   *	callback, but if the driver wants to take a copy of the
325   *	pointer it must call parport_get_port() to do so.
326   *
327   *
328   *	Returns 0 on success. The non device model will always succeeds.
329   *	but the new device model can fail and will return the error code.
330   **/
331  #define parport_register_driver(driver)             \
332  	__parport_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)
333  
334  /* Unregister a high-level driver. */
335  void parport_unregister_driver(struct parport_driver *);
336  
337  /**
338   * module_parport_driver() - Helper macro for registering a modular parport driver
339   * @__parport_driver: struct parport_driver to be used
340   *
341   * Helper macro for parport drivers which do not do anything special in module
342   * init and exit. This eliminates a lot of boilerplate. Each module may only
343   * use this macro once, and calling it replaces module_init() and module_exit().
344   */
345  #define module_parport_driver(__parport_driver) \
346  	module_driver(__parport_driver, parport_register_driver, parport_unregister_driver)
347  
348  /* If parport_register_driver doesn't fit your needs, perhaps
349   * parport_find_xxx does. */
350  extern struct parport *parport_find_number (int);
351  extern struct parport *parport_find_base (unsigned long);
352  
353  /* generic irq handler, if it suits your needs */
354  extern irqreturn_t parport_irq_handler(int irq, void *dev_id);
355  
356  /* Reference counting for ports. */
357  extern struct parport *parport_get_port (struct parport *);
358  extern void parport_put_port (struct parport *);
359  void parport_del_port(struct parport *);
360  
361  struct pardev_cb {
362  	int (*preempt)(void *);
363  	void (*wakeup)(void *);
364  	void *private;
365  	void (*irq_func)(void *);
366  	unsigned int flags;
367  };
368  
369  /*
370   * parport_register_dev_model declares that a device is connected to a
371   * port, and tells the kernel all it needs to know.
372   */
373  struct pardevice *
374  parport_register_dev_model(struct parport *port, const char *name,
375  			   const struct pardev_cb *par_dev_cb, int cnt);
376  
377  /* parport_unregister unlinks a device from the chain. */
378  extern void parport_unregister_device(struct pardevice *dev);
379  
380  /* parport_claim tries to gain ownership of the port for a particular
381     driver.  This may fail (return non-zero) if another driver is busy.
382     If this driver has registered an interrupt handler, it will be
383     enabled.  */
384  extern int parport_claim(struct pardevice *dev);
385  
386  /* parport_claim_or_block is the same, but sleeps if the port cannot
387     be claimed.  Return value is 1 if it slept, 0 normally and -errno
388     on error.  */
389  extern int parport_claim_or_block(struct pardevice *dev);
390  
391  /* parport_release reverses a previous parport_claim.  This can never
392     fail, though the effects are undefined (except that they are bad)
393     if you didn't previously own the port.  Once you have released the
394     port you should make sure that neither your code nor the hardware
395     on the port tries to initiate any communication without first
396     re-claiming the port.  If you mess with the port state (enabling
397     ECP for example) you should clean up before releasing the port. */
398  
399  extern void parport_release(struct pardevice *dev);
400  
401  /**
402   * parport_yield - relinquish a parallel port temporarily
403   * @dev: a device on the parallel port
404   *
405   * This function relinquishes the port if it would be helpful to other
406   * drivers to do so.  Afterwards it tries to reclaim the port using
407   * parport_claim(), and the return value is the same as for
408   * parport_claim().  If it fails, the port is left unclaimed and it is
409   * the driver's responsibility to reclaim the port.
410   *
411   * The parport_yield() and parport_yield_blocking() functions are for
412   * marking points in the driver at which other drivers may claim the
413   * port and use their devices.  Yielding the port is similar to
414   * releasing it and reclaiming it, but is more efficient because no
415   * action is taken if there are no other devices needing the port.  In
416   * fact, nothing is done even if there are other devices waiting but
417   * the current device is still within its "timeslice".  The default
418   * timeslice is half a second, but it can be adjusted via the /proc
419   * interface.
420   **/
parport_yield(struct pardevice * dev)421  static __inline__ int parport_yield(struct pardevice *dev)
422  {
423  	unsigned long int timeslip = (jiffies - dev->time);
424  	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
425  		return 0;
426  	parport_release(dev);
427  	return parport_claim(dev);
428  }
429  
430  /**
431   * parport_yield_blocking - relinquish a parallel port temporarily
432   * @dev: a device on the parallel port
433   *
434   * This function relinquishes the port if it would be helpful to other
435   * drivers to do so.  Afterwards it tries to reclaim the port using
436   * parport_claim_or_block(), and the return value is the same as for
437   * parport_claim_or_block().
438   **/
parport_yield_blocking(struct pardevice * dev)439  static __inline__ int parport_yield_blocking(struct pardevice *dev)
440  {
441  	unsigned long int timeslip = (jiffies - dev->time);
442  	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
443  		return 0;
444  	parport_release(dev);
445  	return parport_claim_or_block(dev);
446  }
447  
448  /* Flags used to identify what a device does. */
449  #define PARPORT_DEV_TRAN		0	/* WARNING !! DEPRECATED !! */
450  #define PARPORT_DEV_LURK		(1<<0)	/* WARNING !! DEPRECATED !! */
451  #define PARPORT_DEV_EXCL		(1<<1)	/* Need exclusive access. */
452  
453  #define PARPORT_FLAG_EXCL		(1<<1)	/* EXCL driver registered. */
454  
455  /* IEEE1284 functions */
456  extern void parport_ieee1284_interrupt (void *);
457  extern int parport_negotiate (struct parport *, int mode);
458  extern ssize_t parport_write (struct parport *, const void *buf, size_t len);
459  extern ssize_t parport_read (struct parport *, void *buf, size_t len);
460  
461  #define PARPORT_INACTIVITY_O_NONBLOCK 1
462  extern long parport_set_timeout (struct pardevice *, long inactivity);
463  
464  extern int parport_wait_event (struct parport *, long timeout);
465  extern int parport_wait_peripheral (struct parport *port,
466  				    unsigned char mask,
467  				    unsigned char val);
468  extern int parport_poll_peripheral (struct parport *port,
469  				    unsigned char mask,
470  				    unsigned char val,
471  				    int usec);
472  
473  /* For architectural drivers */
474  extern size_t parport_ieee1284_write_compat (struct parport *,
475  					     const void *, size_t, int);
476  extern size_t parport_ieee1284_read_nibble (struct parport *,
477  					    void *, size_t, int);
478  extern size_t parport_ieee1284_read_byte (struct parport *,
479  					  void *, size_t, int);
480  extern size_t parport_ieee1284_ecp_read_data (struct parport *,
481  					      void *, size_t, int);
482  extern size_t parport_ieee1284_ecp_write_data (struct parport *,
483  					       const void *, size_t, int);
484  extern size_t parport_ieee1284_ecp_write_addr (struct parport *,
485  					       const void *, size_t, int);
486  extern size_t parport_ieee1284_epp_write_data (struct parport *,
487  					       const void *, size_t, int);
488  extern size_t parport_ieee1284_epp_read_data (struct parport *,
489  					      void *, size_t, int);
490  extern size_t parport_ieee1284_epp_write_addr (struct parport *,
491  					       const void *, size_t, int);
492  extern size_t parport_ieee1284_epp_read_addr (struct parport *,
493  					      void *, size_t, int);
494  
495  /* IEEE1284.3 functions */
496  #define daisy_dev_name "Device ID probe"
497  extern int parport_daisy_init (struct parport *port);
498  extern void parport_daisy_fini (struct parport *port);
499  extern struct pardevice *parport_open (int devnum, const char *name);
500  extern void parport_close (struct pardevice *dev);
501  extern ssize_t parport_device_id (int devnum, char *buffer, size_t len);
502  extern void parport_daisy_deselect_all (struct parport *port);
503  extern int parport_daisy_select (struct parport *port, int daisy, int mode);
504  
505  /* Lowlevel drivers _can_ call this support function to handle irqs.  */
parport_generic_irq(struct parport * port)506  static inline void parport_generic_irq(struct parport *port)
507  {
508  	parport_ieee1284_interrupt (port);
509  	read_lock(&port->cad_lock);
510  	if (port->cad && port->cad->irq_func)
511  		port->cad->irq_func(port->cad->private);
512  	read_unlock(&port->cad_lock);
513  }
514  
515  /* Prototypes from parport_procfs */
516  extern int parport_proc_register(struct parport *pp);
517  extern int parport_proc_unregister(struct parport *pp);
518  extern int parport_device_proc_register(struct pardevice *device);
519  extern int parport_device_proc_unregister(struct pardevice *device);
520  
521  /* If PC hardware is the only type supported, we can optimise a bit.  */
522  #if !defined(CONFIG_PARPORT_NOT_PC)
523  
524  #include <linux/parport_pc.h>
525  #define parport_write_data(p,x)            parport_pc_write_data(p,x)
526  #define parport_read_data(p)               parport_pc_read_data(p)
527  #define parport_write_control(p,x)         parport_pc_write_control(p,x)
528  #define parport_read_control(p)            parport_pc_read_control(p)
529  #define parport_frob_control(p,m,v)        parport_pc_frob_control(p,m,v)
530  #define parport_read_status(p)             parport_pc_read_status(p)
531  #define parport_enable_irq(p)              parport_pc_enable_irq(p)
532  #define parport_disable_irq(p)             parport_pc_disable_irq(p)
533  #define parport_data_forward(p)            parport_pc_data_forward(p)
534  #define parport_data_reverse(p)            parport_pc_data_reverse(p)
535  
536  #else  /*  !CONFIG_PARPORT_NOT_PC  */
537  
538  /* Generic operations vector through the dispatch table. */
539  #define parport_write_data(p,x)            (p)->ops->write_data(p,x)
540  #define parport_read_data(p)               (p)->ops->read_data(p)
541  #define parport_write_control(p,x)         (p)->ops->write_control(p,x)
542  #define parport_read_control(p)            (p)->ops->read_control(p)
543  #define parport_frob_control(p,m,v)        (p)->ops->frob_control(p,m,v)
544  #define parport_read_status(p)             (p)->ops->read_status(p)
545  #define parport_enable_irq(p)              (p)->ops->enable_irq(p)
546  #define parport_disable_irq(p)             (p)->ops->disable_irq(p)
547  #define parport_data_forward(p)            (p)->ops->data_forward(p)
548  #define parport_data_reverse(p)            (p)->ops->data_reverse(p)
549  
550  #endif /*  !CONFIG_PARPORT_NOT_PC  */
551  
552  extern unsigned long parport_default_timeslice;
553  extern int parport_default_spintime;
554  
555  #endif /* _PARPORT_H_ */
556