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 #define PARPORT_NAME_MAX_LEN 15
184 
185 /* A parallel port */
186 struct parport {
187 	unsigned long base;	/* base address */
188 	unsigned long base_hi;  /* base address (hi - ECR) */
189 	unsigned int size;	/* IO extent */
190 	const char *name;
191 	unsigned int modes;
192 	int irq;		/* interrupt (or -1 for none) */
193 	int dma;
194 	int muxport;		/* which muxport (if any) this is */
195 	int portnum;		/* which physical parallel port (not mux) */
196 	struct device *dev;	/* Physical device associated with IO/DMA.
197 				 * This may unfortulately be null if the
198 				 * port has a legacy driver.
199 				 */
200 	struct device bus_dev;	/* to link with the bus */
201 	struct parport *physport;
202 				/* If this is a non-default mux
203 				   parport, i.e. we're a clone of a real
204 				   physical port, this is a pointer to that
205 				   port. The locking is only done in the
206 				   real port.  For a clone port, the
207 				   following structure members are
208 				   meaningless: devices, cad, muxsel,
209 				   waithead, waittail, flags, pdir,
210 				   dev, ieee1284, *_lock.
211 
212 				   It this is a default mux parport, or
213 				   there is no mux involved, this points to
214 				   ourself. */
215 
216 	struct pardevice *devices;
217 	struct pardevice *cad;	/* port owner */
218 	int daisy;		/* currently selected daisy addr */
219 	int muxsel;		/* currently selected mux port */
220 
221 	struct pardevice *waithead;
222 	struct pardevice *waittail;
223 
224 	struct list_head list;
225 	struct timer_list timer;
226 	unsigned int flags;
227 
228 	void *sysctl_table;
229 	struct parport_device_info probe_info[5]; /* 0-3 + non-IEEE1284.3 */
230 	struct ieee1284_info ieee1284;
231 
232 	struct parport_operations *ops;
233 	void *private_data;     /* for lowlevel driver */
234 
235 	int number;		/* port index - the `n' in `parportn' */
236 	spinlock_t pardevice_lock;
237 	spinlock_t waitlist_lock;
238 	rwlock_t cad_lock;
239 
240 	int spintime;
241 	atomic_t ref_count;
242 
243 	unsigned long devflags;
244 #define PARPORT_DEVPROC_REGISTERED	0
245 	struct pardevice *proc_device;	/* Currently register proc device */
246 
247 	struct list_head full_list;
248 	struct parport *slaves[3];
249 };
250 
251 #define to_parport_dev(n) container_of(n, struct parport, bus_dev)
252 
253 #define DEFAULT_SPIN_TIME 500 /* us */
254 
255 struct parport_driver {
256 	const char *name;
257 	void (*attach) (struct parport *);
258 	void (*detach) (struct parport *);
259 	void (*match_port)(struct parport *);
260 	int (*probe)(struct pardevice *);
261 	struct device_driver driver;
262 	bool devmodel;
263 	struct list_head list;
264 };
265 
266 #define to_parport_driver(n) container_of(n, struct parport_driver, driver)
267 
268 int parport_bus_init(void);
269 void parport_bus_exit(void);
270 
271 /* parport_register_port registers a new parallel port at the given
272    address (if one does not already exist) and returns a pointer to it.
273    This entails claiming the I/O region, IRQ and DMA.  NULL is returned
274    if initialisation fails. */
275 struct parport *parport_register_port(unsigned long base, int irq, int dma,
276 				      struct parport_operations *ops);
277 
278 /* Once a registered port is ready for high-level drivers to use, the
279    low-level driver that registered it should announce it.  This will
280    call the high-level drivers' attach() functions (after things like
281    determining the IEEE 1284.3 topology of the port and collecting
282    DeviceIDs). */
283 void parport_announce_port (struct parport *port);
284 
285 /* Unregister a port. */
286 extern void parport_remove_port(struct parport *port);
287 
288 /* Register a new high-level driver. */
289 
290 int __must_check __parport_register_driver(struct parport_driver *,
291 					   struct module *,
292 					   const char *mod_name);
293 /*
294  * parport_register_driver must be a macro so that KBUILD_MODNAME can
295  * be expanded
296  */
297 
298 /**
299  *	parport_register_driver - register a parallel port device driver
300  *	@driver: structure describing the driver
301  *
302  *	This can be called by a parallel port device driver in order
303  *	to receive notifications about ports being found in the
304  *	system, as well as ports no longer available.
305  *
306  *	If devmodel is true then the new device model is used
307  *	for registration.
308  *
309  *	The @driver structure is allocated by the caller and must not be
310  *	deallocated until after calling parport_unregister_driver().
311  *
312  *	If using the non device model:
313  *	The driver's attach() function may block.  The port that
314  *	attach() is given will be valid for the duration of the
315  *	callback, but if the driver wants to take a copy of the
316  *	pointer it must call parport_get_port() to do so.  Calling
317  *	parport_register_device() on that port will do this for you.
318  *
319  *	The driver's detach() function may block.  The port that
320  *	detach() is given will be valid for the duration of the
321  *	callback, but if the driver wants to take a copy of the
322  *	pointer it must call parport_get_port() to do so.
323  *
324  *
325  *	Returns 0 on success. The non device model will always succeeds.
326  *	but the new device model can fail and will return the error code.
327  **/
328 #define parport_register_driver(driver)             \
329 	__parport_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)
330 
331 /* Unregister a high-level driver. */
332 void parport_unregister_driver(struct parport_driver *);
333 
334 /**
335  * module_parport_driver() - Helper macro for registering a modular parport driver
336  * @__parport_driver: struct parport_driver to be used
337  *
338  * Helper macro for parport drivers which do not do anything special in module
339  * init and exit. This eliminates a lot of boilerplate. Each module may only
340  * use this macro once, and calling it replaces module_init() and module_exit().
341  */
342 #define module_parport_driver(__parport_driver) \
343 	module_driver(__parport_driver, parport_register_driver, parport_unregister_driver)
344 
345 /* If parport_register_driver doesn't fit your needs, perhaps
346  * parport_find_xxx does. */
347 extern struct parport *parport_find_number (int);
348 extern struct parport *parport_find_base (unsigned long);
349 
350 /* generic irq handler, if it suits your needs */
351 extern irqreturn_t parport_irq_handler(int irq, void *dev_id);
352 
353 /* Reference counting for ports. */
354 extern struct parport *parport_get_port (struct parport *);
355 extern void parport_put_port (struct parport *);
356 void parport_del_port(struct parport *);
357 
358 struct pardev_cb {
359 	int (*preempt)(void *);
360 	void (*wakeup)(void *);
361 	void *private;
362 	void (*irq_func)(void *);
363 	unsigned int flags;
364 };
365 
366 /*
367  * parport_register_dev_model declares that a device is connected to a
368  * port, and tells the kernel all it needs to know.
369  */
370 struct pardevice *
371 parport_register_dev_model(struct parport *port, const char *name,
372 			   const struct pardev_cb *par_dev_cb, int cnt);
373 
374 /* parport_unregister unlinks a device from the chain. */
375 extern void parport_unregister_device(struct pardevice *dev);
376 
377 /* parport_claim tries to gain ownership of the port for a particular
378    driver.  This may fail (return non-zero) if another driver is busy.
379    If this driver has registered an interrupt handler, it will be
380    enabled.  */
381 extern int parport_claim(struct pardevice *dev);
382 
383 /* parport_claim_or_block is the same, but sleeps if the port cannot
384    be claimed.  Return value is 1 if it slept, 0 normally and -errno
385    on error.  */
386 extern int parport_claim_or_block(struct pardevice *dev);
387 
388 /* parport_release reverses a previous parport_claim.  This can never
389    fail, though the effects are undefined (except that they are bad)
390    if you didn't previously own the port.  Once you have released the
391    port you should make sure that neither your code nor the hardware
392    on the port tries to initiate any communication without first
393    re-claiming the port.  If you mess with the port state (enabling
394    ECP for example) you should clean up before releasing the port. */
395 
396 extern void parport_release(struct pardevice *dev);
397 
398 /**
399  * parport_yield - relinquish a parallel port temporarily
400  * @dev: a device on the parallel port
401  *
402  * This function relinquishes the port if it would be helpful to other
403  * drivers to do so.  Afterwards it tries to reclaim the port using
404  * parport_claim(), and the return value is the same as for
405  * parport_claim().  If it fails, the port is left unclaimed and it is
406  * the driver's responsibility to reclaim the port.
407  *
408  * The parport_yield() and parport_yield_blocking() functions are for
409  * marking points in the driver at which other drivers may claim the
410  * port and use their devices.  Yielding the port is similar to
411  * releasing it and reclaiming it, but is more efficient because no
412  * action is taken if there are no other devices needing the port.  In
413  * fact, nothing is done even if there are other devices waiting but
414  * the current device is still within its "timeslice".  The default
415  * timeslice is half a second, but it can be adjusted via the /proc
416  * interface.
417  **/
parport_yield(struct pardevice * dev)418 static __inline__ int parport_yield(struct pardevice *dev)
419 {
420 	unsigned long int timeslip = (jiffies - dev->time);
421 	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
422 		return 0;
423 	parport_release(dev);
424 	return parport_claim(dev);
425 }
426 
427 /**
428  * parport_yield_blocking - relinquish a parallel port temporarily
429  * @dev: a device on the parallel port
430  *
431  * This function relinquishes the port if it would be helpful to other
432  * drivers to do so.  Afterwards it tries to reclaim the port using
433  * parport_claim_or_block(), and the return value is the same as for
434  * parport_claim_or_block().
435  **/
parport_yield_blocking(struct pardevice * dev)436 static __inline__ int parport_yield_blocking(struct pardevice *dev)
437 {
438 	unsigned long int timeslip = (jiffies - dev->time);
439 	if ((dev->port->waithead == NULL) || (timeslip < dev->timeslice))
440 		return 0;
441 	parport_release(dev);
442 	return parport_claim_or_block(dev);
443 }
444 
445 /* Flags used to identify what a device does. */
446 #define PARPORT_DEV_TRAN		0	/* WARNING !! DEPRECATED !! */
447 #define PARPORT_DEV_LURK		(1<<0)	/* WARNING !! DEPRECATED !! */
448 #define PARPORT_DEV_EXCL		(1<<1)	/* Need exclusive access. */
449 
450 #define PARPORT_FLAG_EXCL		(1<<1)	/* EXCL driver registered. */
451 
452 /* IEEE1284 functions */
453 extern void parport_ieee1284_interrupt (void *);
454 extern int parport_negotiate (struct parport *, int mode);
455 extern ssize_t parport_write (struct parport *, const void *buf, size_t len);
456 extern ssize_t parport_read (struct parport *, void *buf, size_t len);
457 
458 #define PARPORT_INACTIVITY_O_NONBLOCK 1
459 extern long parport_set_timeout (struct pardevice *, long inactivity);
460 
461 extern int parport_wait_event (struct parport *, long timeout);
462 extern int parport_wait_peripheral (struct parport *port,
463 				    unsigned char mask,
464 				    unsigned char val);
465 extern int parport_poll_peripheral (struct parport *port,
466 				    unsigned char mask,
467 				    unsigned char val,
468 				    int usec);
469 
470 /* For architectural drivers */
471 extern size_t parport_ieee1284_write_compat (struct parport *,
472 					     const void *, size_t, int);
473 extern size_t parport_ieee1284_read_nibble (struct parport *,
474 					    void *, size_t, int);
475 extern size_t parport_ieee1284_read_byte (struct parport *,
476 					  void *, size_t, int);
477 extern size_t parport_ieee1284_ecp_read_data (struct parport *,
478 					      void *, size_t, int);
479 extern size_t parport_ieee1284_ecp_write_data (struct parport *,
480 					       const void *, size_t, int);
481 extern size_t parport_ieee1284_ecp_write_addr (struct parport *,
482 					       const void *, size_t, int);
483 extern size_t parport_ieee1284_epp_write_data (struct parport *,
484 					       const void *, size_t, int);
485 extern size_t parport_ieee1284_epp_read_data (struct parport *,
486 					      void *, size_t, int);
487 extern size_t parport_ieee1284_epp_write_addr (struct parport *,
488 					       const void *, size_t, int);
489 extern size_t parport_ieee1284_epp_read_addr (struct parport *,
490 					      void *, size_t, int);
491 
492 /* IEEE1284.3 functions */
493 #define daisy_dev_name "Device ID probe"
494 extern int parport_daisy_init (struct parport *port);
495 extern void parport_daisy_fini (struct parport *port);
496 extern struct pardevice *parport_open (int devnum, const char *name);
497 extern void parport_close (struct pardevice *dev);
498 extern ssize_t parport_device_id (int devnum, char *buffer, size_t len);
499 extern void parport_daisy_deselect_all (struct parport *port);
500 extern int parport_daisy_select (struct parport *port, int daisy, int mode);
501 
502 /* Lowlevel drivers _can_ call this support function to handle irqs.  */
parport_generic_irq(struct parport * port)503 static inline void parport_generic_irq(struct parport *port)
504 {
505 	parport_ieee1284_interrupt (port);
506 	read_lock(&port->cad_lock);
507 	if (port->cad && port->cad->irq_func)
508 		port->cad->irq_func(port->cad->private);
509 	read_unlock(&port->cad_lock);
510 }
511 
512 /* Prototypes from parport_procfs */
513 extern int parport_proc_register(struct parport *pp);
514 extern int parport_proc_unregister(struct parport *pp);
515 extern int parport_device_proc_register(struct pardevice *device);
516 extern int parport_device_proc_unregister(struct pardevice *device);
517 
518 /* If PC hardware is the only type supported, we can optimise a bit.  */
519 #if !defined(CONFIG_PARPORT_NOT_PC) && defined(CONFIG_PARPORT_PC)
520 
521 #include <linux/parport_pc.h>
522 #define parport_write_data(p,x)            parport_pc_write_data(p,x)
523 #define parport_read_data(p)               parport_pc_read_data(p)
524 #define parport_write_control(p,x)         parport_pc_write_control(p,x)
525 #define parport_read_control(p)            parport_pc_read_control(p)
526 #define parport_frob_control(p,m,v)        parport_pc_frob_control(p,m,v)
527 #define parport_read_status(p)             parport_pc_read_status(p)
528 #define parport_enable_irq(p)              parport_pc_enable_irq(p)
529 #define parport_disable_irq(p)             parport_pc_disable_irq(p)
530 #define parport_data_forward(p)            parport_pc_data_forward(p)
531 #define parport_data_reverse(p)            parport_pc_data_reverse(p)
532 
533 #else  /*  !CONFIG_PARPORT_NOT_PC  */
534 
535 /* Generic operations vector through the dispatch table. */
536 #define parport_write_data(p,x)            (p)->ops->write_data(p,x)
537 #define parport_read_data(p)               (p)->ops->read_data(p)
538 #define parport_write_control(p,x)         (p)->ops->write_control(p,x)
539 #define parport_read_control(p)            (p)->ops->read_control(p)
540 #define parport_frob_control(p,m,v)        (p)->ops->frob_control(p,m,v)
541 #define parport_read_status(p)             (p)->ops->read_status(p)
542 #define parport_enable_irq(p)              (p)->ops->enable_irq(p)
543 #define parport_disable_irq(p)             (p)->ops->disable_irq(p)
544 #define parport_data_forward(p)            (p)->ops->data_forward(p)
545 #define parport_data_reverse(p)            (p)->ops->data_reverse(p)
546 
547 #endif /*  !CONFIG_PARPORT_NOT_PC  */
548 
549 extern unsigned long parport_default_timeslice;
550 extern int parport_default_spintime;
551 
552 #endif /* _PARPORT_H_ */
553