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 ip32_parport_state {
44  	unsigned int dcr;
45  	unsigned int ecr;
46  };
47  
48  struct parport_state {
49  	union {
50  		struct pc_parport_state pc;
51  		/* ARC has no state. */
52  		struct ax_parport_state ax;
53  		struct amiga_parport_state amiga;
54  		/* Atari has not state. */
55  		struct ip32_parport_state ip32;
56  		void *misc;
57  	} u;
58  };
59  
60  struct parport_operations {
61  	/* IBM PC-style virtual registers. */
62  	void (*write_data)(struct parport *, unsigned char);
63  	unsigned char (*read_data)(struct parport *);
64  
65  	void (*write_control)(struct parport *, unsigned char);
66  	unsigned char (*read_control)(struct parport *);
67  	unsigned char (*frob_control)(struct parport *, unsigned char mask,
68  				      unsigned char val);
69  
70  	unsigned char (*read_status)(struct parport *);
71  
72  	/* IRQs. */
73  	void (*enable_irq)(struct parport *);
74  	void (*disable_irq)(struct parport *);
75  
76  	/* Data direction. */
77  	void (*data_forward) (struct parport *);
78  	void (*data_reverse) (struct parport *);
79  
80  	/* For core parport code. */
81  	void (*init_state)(struct pardevice *, struct parport_state *);
82  	void (*save_state)(struct parport *, struct parport_state *);
83  	void (*restore_state)(struct parport *, struct parport_state *);
84  
85  	/* Block read/write */
86  	size_t (*epp_write_data) (struct parport *port, const void *buf,
87  				  size_t len, int flags);
88  	size_t (*epp_read_data) (struct parport *port, void *buf, size_t len,
89  				 int flags);
90  	size_t (*epp_write_addr) (struct parport *port, const void *buf,
91  				  size_t len, int flags);
92  	size_t (*epp_read_addr) (struct parport *port, void *buf, size_t len,
93  				 int flags);
94  
95  	size_t (*ecp_write_data) (struct parport *port, const void *buf,
96  				  size_t len, int flags);
97  	size_t (*ecp_read_data) (struct parport *port, void *buf, size_t len,
98  				 int flags);
99  	size_t (*ecp_write_addr) (struct parport *port, const void *buf,
100  				  size_t len, int flags);
101  
102  	size_t (*compat_write_data) (struct parport *port, const void *buf,
103  				     size_t len, int flags);
104  	size_t (*nibble_read_data) (struct parport *port, void *buf,
105  				    size_t len, int flags);
106  	size_t (*byte_read_data) (struct parport *port, void *buf,
107  				  size_t len, int flags);
108  	struct module *owner;
109  };
110  
111  struct parport_device_info {
112  	parport_device_class class;
113  	const char *class_name;
114  	const char *mfr;
115  	const char *model;
116  	const char *cmdset;
117  	const char *description;
118  };
119  
120  /* Each device can have two callback functions:
121   *  1) a preemption function, called by the resource manager to request
122   *     that the driver relinquish control of the port.  The driver should
123   *     return zero if it agrees to release the port, and nonzero if it
124   *     refuses.  Do not call parport_release() - the kernel will do this
125   *     implicitly.
126   *
127   *  2) a wake-up function, called by the resource manager to tell drivers
128   *     that the port is available to be claimed.  If a driver wants to use
129   *     the port, it should call parport_claim() here.
130   */
131  
132  /* A parallel port device */
133  struct pardevice {
134  	const char *name;
135  	struct parport *port;
136  	int daisy;
137  	int (*preempt)(void *);
138  	void (*wakeup)(void *);
139  	void *private;
140  	void (*irq_func)(void *);
141  	unsigned int flags;
142  	struct pardevice *next;
143  	struct pardevice *prev;
144  	struct device dev;
145  	bool devmodel;
146  	struct parport_state *state;     /* saved status over preemption */
147  	wait_queue_head_t wait_q;
148  	unsigned long int time;
149  	unsigned long int timeslice;
150  	volatile long int timeout;
151  	unsigned long waiting;		 /* long req'd for set_bit --RR */
152  	struct pardevice *waitprev;
153  	struct pardevice *waitnext;
154  	void * sysctl_table;
155  };
156  
157  #define to_pardevice(n) container_of(n, struct pardevice, dev)
158  
159  /* IEEE1284 information */
160  
161  /* IEEE1284 phases. These are exposed to userland through ppdev IOCTL
162   * PP[GS]ETPHASE, so do not change existing values. */
163  enum ieee1284_phase {
164  	IEEE1284_PH_FWD_DATA,
165  	IEEE1284_PH_FWD_IDLE,
166  	IEEE1284_PH_TERMINATE,
167  	IEEE1284_PH_NEGOTIATION,
168  	IEEE1284_PH_HBUSY_DNA,
169  	IEEE1284_PH_REV_IDLE,
170  	IEEE1284_PH_HBUSY_DAVAIL,
171  	IEEE1284_PH_REV_DATA,
172  	IEEE1284_PH_ECP_SETUP,
173  	IEEE1284_PH_ECP_FWD_TO_REV,
174  	IEEE1284_PH_ECP_REV_TO_FWD,
175  	IEEE1284_PH_ECP_DIR_UNKNOWN,
176  };
177  struct ieee1284_info {
178  	int mode;
179  	volatile enum ieee1284_phase phase;
180  	struct semaphore irq;
181  };
182  
183  /* A parallel port */
184  struct parport {
185  	unsigned long base;	/* base address */
186  	unsigned long base_hi;  /* base address (hi - ECR) */
187  	unsigned int size;	/* IO extent */
188  	const char *name;
189  	unsigned int modes;
190  	int irq;		/* interrupt (or -1 for none) */
191  	int dma;
192  	int muxport;		/* which muxport (if any) this is */
193  	int portnum;		/* which physical parallel port (not mux) */
194  	struct device *dev;	/* Physical device associated with IO/DMA.
195  				 * This may unfortulately be null if the
196  				 * port has a legacy driver.
197  				 */
198  	struct device bus_dev;	/* to link with the bus */
199  	struct parport *physport;
200  				/* If this is a non-default mux
201  				   parport, i.e. we're a clone of a real
202  				   physical port, this is a pointer to that
203  				   port. The locking is only done in the
204  				   real port.  For a clone port, the
205  				   following structure members are
206  				   meaningless: devices, cad, muxsel,
207  				   waithead, waittail, flags, pdir,
208  				   dev, ieee1284, *_lock.
209  
210  				   It this is a default mux parport, or
211  				   there is no mux involved, this points to
212  				   ourself. */
213  
214  	struct pardevice *devices;
215  	struct pardevice *cad;	/* port owner */
216  	int daisy;		/* currently selected daisy addr */
217  	int muxsel;		/* currently selected mux port */
218  
219  	struct pardevice *waithead;
220  	struct pardevice *waittail;
221  
222  	struct list_head list;
223  	struct timer_list timer;
224  	unsigned int flags;
225  
226  	void *sysctl_table;
227  	struct parport_device_info probe_info[5]; /* 0-3 + non-IEEE1284.3 */
228  	struct ieee1284_info ieee1284;
229  
230  	struct parport_operations *ops;
231  	void *private_data;     /* for lowlevel driver */
232  
233  	int number;		/* port index - the `n' in `parportn' */
234  	spinlock_t pardevice_lock;
235  	spinlock_t waitlist_lock;
236  	rwlock_t cad_lock;
237  
238  	int spintime;
239  	atomic_t ref_count;
240  
241  	unsigned long devflags;
242  #define PARPORT_DEVPROC_REGISTERED	0
243  	struct pardevice *proc_device;	/* Currently register proc device */
244  
245  	struct list_head full_list;
246  	struct parport *slaves[3];
247  };
248  
249  #define to_parport_dev(n) container_of(n, struct parport, bus_dev)
250  
251  #define DEFAULT_SPIN_TIME 500 /* us */
252  
253  struct parport_driver {
254  	const char *name;
255  	void (*detach) (struct parport *);
256  	void (*match_port)(struct parport *);
257  	int (*probe)(struct pardevice *);
258  	struct device_driver driver;
259  };
260  
261  #define to_parport_driver(n) container_of(n, struct parport_driver, driver)
262  
263  int parport_bus_init(void);
264  void parport_bus_exit(void);
265  
266  /* parport_register_port registers a new parallel port at the given
267     address (if one does not already exist) and returns a pointer to it.
268     This entails claiming the I/O region, IRQ and DMA.  NULL is returned
269     if initialisation fails. */
270  struct parport *parport_register_port(unsigned long base, int irq, int dma,
271  				      struct parport_operations *ops);
272  
273  /* Once a registered port is ready for high-level drivers to use, the
274     low-level driver that registered it should announce it.  This will
275     call the high-level drivers' attach() functions (after things like
276     determining the IEEE 1284.3 topology of the port and collecting
277     DeviceIDs). */
278  void parport_announce_port (struct parport *port);
279  
280  /* Unregister a port. */
281  extern void parport_remove_port(struct parport *port);
282  
283  /* Register a new high-level driver. */
284  
285  int __must_check __parport_register_driver(struct parport_driver *,
286  					   struct module *,
287  					   const char *mod_name);
288  /*
289   * parport_register_driver must be a macro so that KBUILD_MODNAME can
290   * be expanded
291   */
292  
293  /**
294   *	parport_register_driver - register a parallel port device driver
295   *	@driver: structure describing the driver
296   *
297   *	This can be called by a parallel port device driver in order
298   *	to receive notifications about ports being found in the
299   *	system, as well as ports no longer available.
300   *
301   *	The @driver structure is allocated by the caller and must not be
302   *	deallocated until after calling parport_unregister_driver().
303   *
304   *	If using the non device model:
305   *	The driver's attach() function may block.  The port that
306   *	attach() is given will be valid for the duration of the
307   *	callback, but if the driver wants to take a copy of the
308   *	pointer it must call parport_get_port() to do so.  Calling
309   *	parport_register_device() on that port will do this for you.
310   *
311   *	The driver's detach() function may block.  The port that
312   *	detach() is given will be valid for the duration of the
313   *	callback, but if the driver wants to take a copy of the
314   *	pointer it must call parport_get_port() to do so.
315   *
316   *
317   *	Returns 0 on success. The non device model will always succeeds.
318   *	but the new device model can fail and will return the error code.
319   **/
320  #define parport_register_driver(driver)             \
321  	__parport_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)
322  
323  /* Unregister a high-level driver. */
324  void parport_unregister_driver(struct parport_driver *);
325  
326  /**
327   * module_parport_driver() - Helper macro for registering a modular parport driver
328   * @__parport_driver: struct parport_driver to be used
329   *
330   * Helper macro for parport drivers which do not do anything special in module
331   * init and exit. This eliminates a lot of boilerplate. Each module may only
332   * use this macro once, and calling it replaces module_init() and module_exit().
333   */
334  #define module_parport_driver(__parport_driver) \
335  	module_driver(__parport_driver, parport_register_driver, parport_unregister_driver)
336  
337  /* If parport_register_driver doesn't fit your needs, perhaps
338   * parport_find_xxx does. */
339  extern struct parport *parport_find_number (int);
340  extern struct parport *parport_find_base (unsigned long);
341  
342  /* generic irq handler, if it suits your needs */
343  extern irqreturn_t parport_irq_handler(int irq, void *dev_id);
344  
345  /* Reference counting for ports. */
346  extern struct parport *parport_get_port (struct parport *);
347  extern void parport_put_port (struct parport *);
348  void parport_del_port(struct parport *);
349  
350  struct pardev_cb {
351  	int (*preempt)(void *);
352  	void (*wakeup)(void *);
353  	void *private;
354  	void (*irq_func)(void *);
355  	unsigned int flags;
356  };
357  
358  /*
359   * parport_register_dev_model declares that a device is connected to a
360   * port, and tells the kernel all it needs to know.
361   */
362  struct pardevice *
363  parport_register_dev_model(struct parport *port, const char *name,
364  			   const struct pardev_cb *par_dev_cb, int cnt);
365  
366  /* parport_unregister unlinks a device from the chain. */
367  extern void parport_unregister_device(struct pardevice *dev);
368  
369  /* parport_claim tries to gain ownership of the port for a particular
370     driver.  This may fail (return non-zero) if another driver is busy.
371     If this driver has registered an interrupt handler, it will be
372     enabled.  */
373  extern int parport_claim(struct pardevice *dev);
374  
375  /* parport_claim_or_block is the same, but sleeps if the port cannot
376     be claimed.  Return value is 1 if it slept, 0 normally and -errno
377     on error.  */
378  extern int parport_claim_or_block(struct pardevice *dev);
379  
380  /* parport_release reverses a previous parport_claim.  This can never
381     fail, though the effects are undefined (except that they are bad)
382     if you didn't previously own the port.  Once you have released the
383     port you should make sure that neither your code nor the hardware
384     on the port tries to initiate any communication without first
385     re-claiming the port.  If you mess with the port state (enabling
386     ECP for example) you should clean up before releasing the port. */
387  
388  extern void parport_release(struct pardevice *dev);
389  
390  /**
391   * parport_yield - relinquish a parallel port temporarily
392   * @dev: a device on the parallel port
393   *
394   * This function relinquishes the port if it would be helpful to other
395   * drivers to do so.  Afterwards it tries to reclaim the port using
396   * parport_claim(), and the return value is the same as for
397   * parport_claim().  If it fails, the port is left unclaimed and it is
398   * the driver's responsibility to reclaim the port.
399   *
400   * The parport_yield() and parport_yield_blocking() functions are for
401   * marking points in the driver at which other drivers may claim the
402   * port and use their devices.  Yielding the port is similar to
403   * releasing it and reclaiming it, but is more efficient because no
404   * action is taken if there are no other devices needing the port.  In
405   * fact, nothing is done even if there are other devices waiting but
406   * the current device is still within its "timeslice".  The default
407   * timeslice is half a second, but it can be adjusted via the /proc
408   * interface.
409   **/
parport_yield(struct pardevice * dev)410  static __inline__ int parport_yield(struct pardevice *dev)
411  {
412  	unsigned long int timeslip = (jiffies - dev->time);
413  	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
414  		return 0;
415  	parport_release(dev);
416  	return parport_claim(dev);
417  }
418  
419  /**
420   * parport_yield_blocking - relinquish a parallel port temporarily
421   * @dev: a device on the parallel port
422   *
423   * This function relinquishes the port if it would be helpful to other
424   * drivers to do so.  Afterwards it tries to reclaim the port using
425   * parport_claim_or_block(), and the return value is the same as for
426   * parport_claim_or_block().
427   **/
parport_yield_blocking(struct pardevice * dev)428  static __inline__ int parport_yield_blocking(struct pardevice *dev)
429  {
430  	unsigned long int timeslip = (jiffies - dev->time);
431  	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
432  		return 0;
433  	parport_release(dev);
434  	return parport_claim_or_block(dev);
435  }
436  
437  /* Flags used to identify what a device does. */
438  #define PARPORT_DEV_TRAN		0	/* WARNING !! DEPRECATED !! */
439  #define PARPORT_DEV_LURK		(1<<0)	/* WARNING !! DEPRECATED !! */
440  #define PARPORT_DEV_EXCL		(1<<1)	/* Need exclusive access. */
441  
442  #define PARPORT_FLAG_EXCL		(1<<1)	/* EXCL driver registered. */
443  
444  /* IEEE1284 functions */
445  extern void parport_ieee1284_interrupt (void *);
446  extern int parport_negotiate (struct parport *, int mode);
447  extern ssize_t parport_write (struct parport *, const void *buf, size_t len);
448  extern ssize_t parport_read (struct parport *, void *buf, size_t len);
449  
450  #define PARPORT_INACTIVITY_O_NONBLOCK 1
451  extern long parport_set_timeout (struct pardevice *, long inactivity);
452  
453  extern int parport_wait_event (struct parport *, long timeout);
454  extern int parport_wait_peripheral (struct parport *port,
455  				    unsigned char mask,
456  				    unsigned char val);
457  extern int parport_poll_peripheral (struct parport *port,
458  				    unsigned char mask,
459  				    unsigned char val,
460  				    int usec);
461  
462  /* For architectural drivers */
463  extern size_t parport_ieee1284_write_compat (struct parport *,
464  					     const void *, size_t, int);
465  extern size_t parport_ieee1284_read_nibble (struct parport *,
466  					    void *, size_t, int);
467  extern size_t parport_ieee1284_read_byte (struct parport *,
468  					  void *, size_t, int);
469  extern size_t parport_ieee1284_ecp_read_data (struct parport *,
470  					      void *, size_t, int);
471  extern size_t parport_ieee1284_ecp_write_data (struct parport *,
472  					       const void *, size_t, int);
473  extern size_t parport_ieee1284_ecp_write_addr (struct parport *,
474  					       const void *, size_t, int);
475  extern size_t parport_ieee1284_epp_write_data (struct parport *,
476  					       const void *, size_t, int);
477  extern size_t parport_ieee1284_epp_read_data (struct parport *,
478  					      void *, size_t, int);
479  extern size_t parport_ieee1284_epp_write_addr (struct parport *,
480  					       const void *, size_t, int);
481  extern size_t parport_ieee1284_epp_read_addr (struct parport *,
482  					      void *, size_t, int);
483  
484  /* IEEE1284.3 functions */
485  #define daisy_dev_name "Device ID probe"
486  extern int parport_daisy_init (struct parport *port);
487  extern void parport_daisy_fini (struct parport *port);
488  extern struct pardevice *parport_open (int devnum, const char *name);
489  extern void parport_close (struct pardevice *dev);
490  extern ssize_t parport_device_id (int devnum, char *buffer, size_t len);
491  extern void parport_daisy_deselect_all (struct parport *port);
492  extern int parport_daisy_select (struct parport *port, int daisy, int mode);
493  
494  /* Lowlevel drivers _can_ call this support function to handle irqs.  */
parport_generic_irq(struct parport * port)495  static inline void parport_generic_irq(struct parport *port)
496  {
497  	parport_ieee1284_interrupt (port);
498  	read_lock(&port->cad_lock);
499  	if (port->cad && port->cad->irq_func)
500  		port->cad->irq_func(port->cad->private);
501  	read_unlock(&port->cad_lock);
502  }
503  
504  /* Prototypes from parport_procfs */
505  extern int parport_proc_register(struct parport *pp);
506  extern int parport_proc_unregister(struct parport *pp);
507  extern int parport_device_proc_register(struct pardevice *device);
508  extern int parport_device_proc_unregister(struct pardevice *device);
509  
510  /* If PC hardware is the only type supported, we can optimise a bit.  */
511  #if !defined(CONFIG_PARPORT_NOT_PC) && defined(CONFIG_PARPORT_PC)
512  
513  #include <linux/parport_pc.h>
514  #define parport_write_data(p,x)            parport_pc_write_data(p,x)
515  #define parport_read_data(p)               parport_pc_read_data(p)
516  #define parport_write_control(p,x)         parport_pc_write_control(p,x)
517  #define parport_read_control(p)            parport_pc_read_control(p)
518  #define parport_frob_control(p,m,v)        parport_pc_frob_control(p,m,v)
519  #define parport_read_status(p)             parport_pc_read_status(p)
520  #define parport_enable_irq(p)              parport_pc_enable_irq(p)
521  #define parport_disable_irq(p)             parport_pc_disable_irq(p)
522  #define parport_data_forward(p)            parport_pc_data_forward(p)
523  #define parport_data_reverse(p)            parport_pc_data_reverse(p)
524  
525  #else  /*  !CONFIG_PARPORT_NOT_PC  */
526  
527  /* Generic operations vector through the dispatch table. */
528  #define parport_write_data(p,x)            (p)->ops->write_data(p,x)
529  #define parport_read_data(p)               (p)->ops->read_data(p)
530  #define parport_write_control(p,x)         (p)->ops->write_control(p,x)
531  #define parport_read_control(p)            (p)->ops->read_control(p)
532  #define parport_frob_control(p,m,v)        (p)->ops->frob_control(p,m,v)
533  #define parport_read_status(p)             (p)->ops->read_status(p)
534  #define parport_enable_irq(p)              (p)->ops->enable_irq(p)
535  #define parport_disable_irq(p)             (p)->ops->disable_irq(p)
536  #define parport_data_forward(p)            (p)->ops->data_forward(p)
537  #define parport_data_reverse(p)            (p)->ops->data_reverse(p)
538  
539  #endif /*  !CONFIG_PARPORT_NOT_PC  */
540  
541  extern unsigned long parport_default_timeslice;
542  extern int parport_default_spintime;
543  
544  #endif /* _PARPORT_H_ */
545