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