xref: /linux/include/linux/parport.h (revision ef15ccbb3e8640a723c42ad90eaf81d66ae02017)
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 #define PARPORT_ANNOUNCED		1
244 	struct pardevice *proc_device;	/* Currently register proc device */
245 
246 	struct list_head full_list;
247 	struct parport *slaves[3];
248 };
249 
250 #define to_parport_dev(n) container_of(n, struct parport, bus_dev)
251 
252 #define DEFAULT_SPIN_TIME 500 /* us */
253 
254 struct parport_driver {
255 	const char *name;
256 	void (*detach) (struct parport *);
257 	void (*match_port)(struct parport *);
258 	int (*probe)(struct pardevice *);
259 	struct device_driver driver;
260 };
261 
262 #define to_parport_driver(n) container_of(n, struct parport_driver, driver)
263 
264 int parport_bus_init(void);
265 void parport_bus_exit(void);
266 
267 /* parport_register_port registers a new parallel port at the given
268    address (if one does not already exist) and returns a pointer to it.
269    This entails claiming the I/O region, IRQ and DMA.  NULL is returned
270    if initialisation fails. */
271 struct parport *parport_register_port(unsigned long base, int irq, int dma,
272 				      struct parport_operations *ops);
273 
274 /* Once a registered port is ready for high-level drivers to use, the
275    low-level driver that registered it should announce it.  This will
276    call the high-level drivers' attach() functions (after things like
277    determining the IEEE 1284.3 topology of the port and collecting
278    DeviceIDs). */
279 void parport_announce_port (struct parport *port);
280 
281 /* Unregister a port. */
282 extern void parport_remove_port(struct parport *port);
283 
284 /* Register a new high-level driver. */
285 
286 int __must_check __parport_register_driver(struct parport_driver *,
287 					   struct module *,
288 					   const char *mod_name);
289 /*
290  * parport_register_driver must be a macro so that KBUILD_MODNAME can
291  * be expanded
292  */
293 
294 /**
295  *	parport_register_driver - register a parallel port device driver
296  *	@driver: structure describing the driver
297  *
298  *	This can be called by a parallel port device driver in order
299  *	to receive notifications about ports being found in the
300  *	system, as well as ports no longer available.
301  *
302  *	The @driver structure is allocated by the caller and must not be
303  *	deallocated until after calling parport_unregister_driver().
304  *
305  *	If using the non device model:
306  *	The driver's attach() function may block.  The port that
307  *	attach() is given will be valid for the duration of the
308  *	callback, but if the driver wants to take a copy of the
309  *	pointer it must call parport_get_port() to do so.  Calling
310  *	parport_register_device() on that port will do this for you.
311  *
312  *	The driver's detach() function may block.  The port that
313  *	detach() is given will be valid for the duration of the
314  *	callback, but if the driver wants to take a copy of the
315  *	pointer it must call parport_get_port() to do so.
316  *
317  *
318  *	Returns 0 on success. The non device model will always succeeds.
319  *	but the new device model can fail and will return the error code.
320  **/
321 #define parport_register_driver(driver)             \
322 	__parport_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)
323 
324 /* Unregister a high-level driver. */
325 void parport_unregister_driver(struct parport_driver *);
326 
327 /**
328  * module_parport_driver() - Helper macro for registering a modular parport driver
329  * @__parport_driver: struct parport_driver to be used
330  *
331  * Helper macro for parport drivers which do not do anything special in module
332  * init and exit. This eliminates a lot of boilerplate. Each module may only
333  * use this macro once, and calling it replaces module_init() and module_exit().
334  */
335 #define module_parport_driver(__parport_driver) \
336 	module_driver(__parport_driver, parport_register_driver, parport_unregister_driver)
337 
338 /* If parport_register_driver doesn't fit your needs, perhaps
339  * parport_find_xxx does. */
340 extern struct parport *parport_find_number (int);
341 extern struct parport *parport_find_base (unsigned long);
342 
343 /* generic irq handler, if it suits your needs */
344 extern irqreturn_t parport_irq_handler(int irq, void *dev_id);
345 
346 /* Reference counting for ports. */
347 extern struct parport *parport_get_port (struct parport *);
348 extern void parport_put_port (struct parport *);
349 void parport_del_port(struct parport *);
350 
351 struct pardev_cb {
352 	int (*preempt)(void *);
353 	void (*wakeup)(void *);
354 	void *private;
355 	void (*irq_func)(void *);
356 	unsigned int flags;
357 };
358 
359 /*
360  * parport_register_dev_model declares that a device is connected to a
361  * port, and tells the kernel all it needs to know.
362  */
363 struct pardevice *
364 parport_register_dev_model(struct parport *port, const char *name,
365 			   const struct pardev_cb *par_dev_cb, int cnt);
366 
367 /* parport_unregister unlinks a device from the chain. */
368 extern void parport_unregister_device(struct pardevice *dev);
369 
370 /* parport_claim tries to gain ownership of the port for a particular
371    driver.  This may fail (return non-zero) if another driver is busy.
372    If this driver has registered an interrupt handler, it will be
373    enabled.  */
374 extern int parport_claim(struct pardevice *dev);
375 
376 /* parport_claim_or_block is the same, but sleeps if the port cannot
377    be claimed.  Return value is 1 if it slept, 0 normally and -errno
378    on error.  */
379 extern int parport_claim_or_block(struct pardevice *dev);
380 
381 /* parport_release reverses a previous parport_claim.  This can never
382    fail, though the effects are undefined (except that they are bad)
383    if you didn't previously own the port.  Once you have released the
384    port you should make sure that neither your code nor the hardware
385    on the port tries to initiate any communication without first
386    re-claiming the port.  If you mess with the port state (enabling
387    ECP for example) you should clean up before releasing the port. */
388 
389 extern void parport_release(struct pardevice *dev);
390 
391 /**
392  * parport_yield - relinquish a parallel port temporarily
393  * @dev: a device on the parallel port
394  *
395  * This function relinquishes the port if it would be helpful to other
396  * drivers to do so.  Afterwards it tries to reclaim the port using
397  * parport_claim(), and the return value is the same as for
398  * parport_claim().  If it fails, the port is left unclaimed and it is
399  * the driver's responsibility to reclaim the port.
400  *
401  * The parport_yield() and parport_yield_blocking() functions are for
402  * marking points in the driver at which other drivers may claim the
403  * port and use their devices.  Yielding the port is similar to
404  * releasing it and reclaiming it, but is more efficient because no
405  * action is taken if there are no other devices needing the port.  In
406  * fact, nothing is done even if there are other devices waiting but
407  * the current device is still within its "timeslice".  The default
408  * timeslice is half a second, but it can be adjusted via the /proc
409  * interface.
410  **/
411 static __inline__ int parport_yield(struct pardevice *dev)
412 {
413 	unsigned long int timeslip = (jiffies - dev->time);
414 	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
415 		return 0;
416 	parport_release(dev);
417 	return parport_claim(dev);
418 }
419 
420 /**
421  * parport_yield_blocking - relinquish a parallel port temporarily
422  * @dev: a device on the parallel port
423  *
424  * This function relinquishes the port if it would be helpful to other
425  * drivers to do so.  Afterwards it tries to reclaim the port using
426  * parport_claim_or_block(), and the return value is the same as for
427  * parport_claim_or_block().
428  **/
429 static __inline__ int parport_yield_blocking(struct pardevice *dev)
430 {
431 	unsigned long int timeslip = (jiffies - dev->time);
432 	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
433 		return 0;
434 	parport_release(dev);
435 	return parport_claim_or_block(dev);
436 }
437 
438 /* Flags used to identify what a device does. */
439 #define PARPORT_DEV_TRAN		0	/* WARNING !! DEPRECATED !! */
440 #define PARPORT_DEV_LURK		(1<<0)	/* WARNING !! DEPRECATED !! */
441 #define PARPORT_DEV_EXCL		(1<<1)	/* Need exclusive access. */
442 
443 #define PARPORT_FLAG_EXCL		(1<<1)	/* EXCL driver registered. */
444 
445 /* IEEE1284 functions */
446 extern void parport_ieee1284_interrupt (void *);
447 extern int parport_negotiate (struct parport *, int mode);
448 extern ssize_t parport_write (struct parport *, const void *buf, size_t len);
449 extern ssize_t parport_read (struct parport *, void *buf, size_t len);
450 
451 #define PARPORT_INACTIVITY_O_NONBLOCK 1
452 extern long parport_set_timeout (struct pardevice *, long inactivity);
453 
454 extern int parport_wait_event (struct parport *, long timeout);
455 extern int parport_wait_peripheral (struct parport *port,
456 				    unsigned char mask,
457 				    unsigned char val);
458 extern int parport_poll_peripheral (struct parport *port,
459 				    unsigned char mask,
460 				    unsigned char val,
461 				    int usec);
462 
463 /* For architectural drivers */
464 extern size_t parport_ieee1284_write_compat (struct parport *,
465 					     const void *, size_t, int);
466 extern size_t parport_ieee1284_read_nibble (struct parport *,
467 					    void *, size_t, int);
468 extern size_t parport_ieee1284_read_byte (struct parport *,
469 					  void *, size_t, int);
470 extern size_t parport_ieee1284_ecp_read_data (struct parport *,
471 					      void *, size_t, int);
472 extern size_t parport_ieee1284_ecp_write_data (struct parport *,
473 					       const void *, size_t, int);
474 extern size_t parport_ieee1284_ecp_write_addr (struct parport *,
475 					       const void *, size_t, int);
476 extern size_t parport_ieee1284_epp_write_data (struct parport *,
477 					       const void *, size_t, int);
478 extern size_t parport_ieee1284_epp_read_data (struct parport *,
479 					      void *, size_t, int);
480 extern size_t parport_ieee1284_epp_write_addr (struct parport *,
481 					       const void *, size_t, int);
482 extern size_t parport_ieee1284_epp_read_addr (struct parport *,
483 					      void *, size_t, int);
484 
485 /* IEEE1284.3 functions */
486 #define daisy_dev_name "Device ID probe"
487 extern int parport_daisy_init (struct parport *port);
488 extern void parport_daisy_fini (struct parport *port);
489 extern struct pardevice *parport_open (int devnum, const char *name);
490 extern void parport_close (struct pardevice *dev);
491 extern ssize_t parport_device_id (int devnum, char *buffer, size_t len);
492 extern void parport_daisy_deselect_all (struct parport *port);
493 extern int parport_daisy_select (struct parport *port, int daisy, int mode);
494 
495 /* Lowlevel drivers _can_ call this support function to handle irqs.  */
496 static inline void parport_generic_irq(struct parport *port)
497 {
498 	parport_ieee1284_interrupt (port);
499 	read_lock(&port->cad_lock);
500 	if (port->cad && port->cad->irq_func)
501 		port->cad->irq_func(port->cad->private);
502 	read_unlock(&port->cad_lock);
503 }
504 
505 /* Prototypes from parport_procfs */
506 extern int parport_proc_register(struct parport *pp);
507 extern int parport_proc_unregister(struct parport *pp);
508 extern int parport_device_proc_register(struct pardevice *device);
509 extern int parport_device_proc_unregister(struct pardevice *device);
510 
511 /* If PC hardware is the only type supported, we can optimise a bit.  */
512 #if !defined(CONFIG_PARPORT_NOT_PC) && defined(CONFIG_PARPORT_PC)
513 
514 #include <linux/parport_pc.h>
515 #define parport_write_data(p,x)            parport_pc_write_data(p,x)
516 #define parport_read_data(p)               parport_pc_read_data(p)
517 #define parport_write_control(p,x)         parport_pc_write_control(p,x)
518 #define parport_read_control(p)            parport_pc_read_control(p)
519 #define parport_frob_control(p,m,v)        parport_pc_frob_control(p,m,v)
520 #define parport_read_status(p)             parport_pc_read_status(p)
521 #define parport_enable_irq(p)              parport_pc_enable_irq(p)
522 #define parport_disable_irq(p)             parport_pc_disable_irq(p)
523 #define parport_data_forward(p)            parport_pc_data_forward(p)
524 #define parport_data_reverse(p)            parport_pc_data_reverse(p)
525 
526 #else  /*  !CONFIG_PARPORT_NOT_PC  */
527 
528 /* Generic operations vector through the dispatch table. */
529 #define parport_write_data(p,x)            (p)->ops->write_data(p,x)
530 #define parport_read_data(p)               (p)->ops->read_data(p)
531 #define parport_write_control(p,x)         (p)->ops->write_control(p,x)
532 #define parport_read_control(p)            (p)->ops->read_control(p)
533 #define parport_frob_control(p,m,v)        (p)->ops->frob_control(p,m,v)
534 #define parport_read_status(p)             (p)->ops->read_status(p)
535 #define parport_enable_irq(p)              (p)->ops->enable_irq(p)
536 #define parport_disable_irq(p)             (p)->ops->disable_irq(p)
537 #define parport_data_forward(p)            (p)->ops->data_forward(p)
538 #define parport_data_reverse(p)            (p)->ops->data_reverse(p)
539 
540 #endif /*  !CONFIG_PARPORT_NOT_PC  */
541 
542 extern unsigned long parport_default_timeslice;
543 extern int parport_default_spintime;
544 
545 #endif /* _PARPORT_H_ */
546